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Covering Chlorine Contact Basins at the Kanapaha Water Reclamation Facility: Effects on Chlorine Residual, Disinfection ...


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COVERING CHLORINE CONTACT BA SINS AT THE KANAPAHA WATER RECLAMATION FACILITY: EFFECT S ON CHLORINE RESIDUAL, DISINFECTION EFFECTIVENESS, AND DISINFECTION BY-PRODUCT FORMATION By HEATHER L. FITZPATRICK A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULLFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ENGINEERING UNIVERSITY OF FLORIDA 2005

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Copyright 2005 by Heather L Fitzpatrick

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iii ACKNOWLEDGMENTS I would like to thank my supervisory co mmittee members (Dr. Paul Chadik, Dr. David Mazyck, and Dr. Benjamin Koopman) fo r their input and assistance during this investigation. Special thanks go to my supervisory committee chair (Dr. Chadik) for his technical support and guidance during this study; they were of immeasurable significance to this research and to me. Also, I would like to thank the Gainesville Regional Utilities staff for their support throughout the course of th is research. The help of Christina Akly in the field and at the University of Fl orida was of great importance and greatly appreciated. I would also lik e to thank my family, friends, and especially my husband for their continuous support duri ng my graduate career.

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iv TABLE OF CONTENTS page ACKNOWLEDGMENTS.................................................................................................iii LIST OF TABLES............................................................................................................vii LIST OF FIGURES.............................................................................................................x ABSTRACT.....................................................................................................................xv i CHAPTER 1 INTRODUCTION........................................................................................................1 Pilot Study.................................................................................................................... 5 Full-Scale Study............................................................................................................7 Clarifier Chlorine Addition...........................................................................................7 2 REVIEW OF LITERATURE.......................................................................................9 Nitrification/Denitrification..........................................................................................9 Chlorine Disinfection..................................................................................................10 Free Chlorine.......................................................................................................11 Combined Chlorine.............................................................................................12 Break-Point Chlorination.....................................................................................13 Contact Time.......................................................................................................14 Disinfection By-Product Formation...........................................................................15 Sunlight/UV Irradiation..............................................................................................23 3 MATERIALS AND METHODS...............................................................................27 Measured Parameters..................................................................................................27 Global Solar Radiation........................................................................................27 Ultraviolet Radiation...........................................................................................27 Total and Free Chlorine Residual........................................................................28 Total Suspended Solids.......................................................................................29 Total Coliform.....................................................................................................29 Trihalomethane (THM).......................................................................................30 Haloacetic Acid (HAA).......................................................................................30 pH........................................................................................................................31

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v Conductivity........................................................................................................31 Dissolved Oxygen...............................................................................................32 Sampling.....................................................................................................................32 Pilot Scale System......................................................................................................32 Wastewater Feed System Materials.....................................................................34 Chlorine Dosing...................................................................................................37 Pump Test............................................................................................................37 Full Scale....................................................................................................................3 8 Calculations................................................................................................................40 Disinfection By-Product Data Normalization.....................................................40 Trihalomethane no rmalization.....................................................................40 Haloacetic acid normalization......................................................................42 Average Radiation...............................................................................................43 Standard Deviation..............................................................................................44 Paired T-Test.......................................................................................................44 Linear Correlation...............................................................................................45 4 DISCUSSION: PILOT-SCALE BASIN....................................................................47 Solar Radiation/Temperature......................................................................................47 Chlorine Residual.......................................................................................................50 Free Chlorine.......................................................................................................51 Total Chlorine......................................................................................................57 Disinfection By-Products............................................................................................60 Trihalomethane....................................................................................................61 Haloacetic Acid...................................................................................................74 5 DISCUSSION: FULL-SCALE STUDY....................................................................86 Chlorine Residual.......................................................................................................86 Free Chlorine.......................................................................................................86 Total Chlorine......................................................................................................89 Disinfection By-Products............................................................................................91 Trihalomethane....................................................................................................91 Haloacetic Acid.................................................................................................101 6 DISCUSSION: MEASURED PARAMETERS.......................................................112 Temperature..............................................................................................................112 Total Coliform..........................................................................................................112 Total Suspended Solids.............................................................................................113 pH............................................................................................................................. 114 Conductivity.............................................................................................................115 Dissolved Oxygen.....................................................................................................115 7 CONCLUSIONS......................................................................................................117

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vi APPENDIX A PILOT-SCALE BASIN DESIGN............................................................................121 B FLUOROSCEIN TRACER ANALYSIS.................................................................122 C CHLORINE DOSING CALCULATIONS..............................................................126 D COMPILED DATA..................................................................................................127 E PILOT-SCALE DATA.............................................................................................139 F FULL-SCALE DATA..............................................................................................157 G GAS CHROMATOGRAPHY INFORMATION.....................................................165 H T-TEST AND PEARSO N COEFFICIENT TABLES.............................................172 LIST OF REFERENCES.................................................................................................175 BIOGRAPHICAL SKETCH...........................................................................................178

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vii LIST OF TABLES Table page 3-1 Chlorine contact basi n dimension ratios..................................................................33 3-2 Pilot chlorine contact basin dimension.....................................................................33 4-1 Normalization factors used to normali ze OPAQ TTHM effluent concentrations to TRANS TTHM effluent concentrations...................................................................68 4-2 Normalization factors used to normalize OPAQ HAA(5) effluent concentrations to TRANS HAA(5) effluent concentrations.................................................................80 5-1 Normalization factors used to normali ze COV TTHM effluent concentrations to UNCOV TTHM effluent concentrations..................................................................97 5-2 Normalization factors used to normalize COV HAA(5) effluent concentrations to UNCOV HAA(5) effluent concentrations..............................................................108 A-1 South chlorine contact basin..................................................................................121 A-2 North chlorine contact basin..................................................................................121 A-3 Pilot basin...............................................................................................................1 21 B-1 Fluoroscein tracer at KWRF pilot basin, clear top.................................................122 B-2 Conditions during tracer analysis...........................................................................123 B-3 Flouroscein F curve calculation.............................................................................124 B-4 The F curve values.................................................................................................125 C-1 Chlorine dosing duri ng pilot-scale study...............................................................126 C-2 Acid and base addition during pilot-scale study....................................................126 D-1 Pilot-scale study compiled and calculated parameter data.....................................127 D-2 Pilot-scale study compiled chlo rine data and differences......................................128 D-3 Pilot-scale study compiled TTHM data and differences........................................129

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viii D-4 Pilot-scale study compiled TTHM and normalization factors...............................130 D-5 Pilot-scale study compiled normalized TTHM data and differences....................131 D-6 Pilot-scale study compiled HAA(5) data...............................................................132 D-7 Pilot-scale study compiled normalized HAA(5) data............................................133 D-8 Pilot-scale study compiled differenc es in HAA(5) and HAA(5) data..................134 D-9 Full-scale study compiled and calculated parameter data......................................135 D-10 Full-scale study compiled chlori ne data and differences.......................................135 D-11 Full-scale study compiled TTHM data and differences.........................................136 D-12 Full-scale study compiled TTHM and normalization factors................................136 D-13 Full-scale study compiled normalized TTHM data and differences.....................137 D-14 Full-scale study compiled HAA(5) data.................................................................137 D-15 Pilot-scale study compiled normalized HAA(5) data............................................138 D-16 Full-scale study compiled differenc es in HAA(5) and HAA(5) data...................138 E-1 Trihalomethane mass concentrations in the pilot-scale study................................139 E-2 Trihalomethane molar concentrations in the pilot-scale study...............................142 E-3 Haloacetic acid mass concentrations in the pilot-scale study.................................144 E-4 Haloacetic acid molar concentrations in the pilot-scale study...............................146 E-5 Pilot-scale study chlorine effluent concentrations..................................................148 E-6 Pilot-scale probe parameter data............................................................................151 E-7 Pilot-scale data provided by GRU laboratory........................................................154 F-1 Trihalomethane mass concentrations in the full-scale study..................................157 F-2 Trihalomethane molar concentrations in the full-scale study................................159 F-3 Haloacetic acid mass concentrations in the full-scale study..................................160 F-4 Haloacetic acid molar concentrations in the full-scale study.................................161 F-5 Full-scale study chlorine e ffluent concentrations...................................................162

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ix F-6 Full-scale probe parameter data.............................................................................163 F-7 Full-scale data provided by GRU...........................................................................164 H-1 Pilot-scale t-test values...........................................................................................172 H-2 Full-scale t-test values............................................................................................172 H-3 Pilot-scale Pearson coeffici ent and linear correlation value...................................173 H-4 Full-scale Pearson coefficien t and linear correlation values..................................174

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x LIST OF FIGURES Figure page 1-1 Kanapaha Water Reclamati on Facility flow diagram................................................1 1-2 Overhead layout of the KWRF...................................................................................2 1-3 Wastewater process from f iltration through chlorination..........................................2 1-4 Chlorine addition at the clarifiers...............................................................................8 2-1 Percent of free chlorine compound (HOCl and OCl-) versus pH.............................11 2-2 Breakpoint chlorination: Species of chlo rine residuals presen t during chlorination when ammonia is present.........................................................................................14 2-3 The THM species.....................................................................................................16 2-4 The HAA(5) species.................................................................................................17 2-5 Predicted versus the obse rved concentration of CHCl3 for the entire model development database from the 1993 AWWA report..............................................22 2-6 Predicted versus the observed concen tration of DCAA for the entire model development database from the 1993 AWWA report..............................................23 3-1 Radiometer, pyranometer and datalogger setup......................................................28 3-2 Pilot basin system setup...........................................................................................35 3-3 Pilot scale setup; chlorine and acid/ base solution containers, solution pumps, influent water spigot, static mixers, t-split, TRANS and OPAQ basins..................36 3-4 Full-scale setup. (a) Unc overed side of the basin. (b ) Covered side of the basin during the full-scale study........................................................................................38 3-5 Sampling points in the post-aeration basi n and North chlorine contact basin for the full-scale study.........................................................................................................39 4-1 Average global horizontal radiation vers us the average UV radiation.....................48 4-2 The effluent temperature of the TR ANS and OPAQ basins plotted versus the average UV radiation exposure of the TRANS basin over the HRT.......................49

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xi 4-3 Difference in effluent temperature of th e basins (TRANS-OPAQ) plotted versus the average UV radiation over the HRT........................................................................50 4-4 Free chlorine residual sampling sets in particular residual ranges for the TRANS and OPAQ basins.....................................................................................................52 4-5 Free chlorine residual differe nce of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus averag e UV Radiation over the HRT of the wastewater in the basin for all pilot studies.............................................................53 4-6 Free chlorine residual difference of the OPAQ and TRANS basins (TRANS-OPAQ) plotted versus averag e UV radiation over the HRT of the wastewater in the basin fo r baseline parameters......................................................54 4-7 Free chlorine difference of the TRAN S and OPAQ basins (TRANS-OPAQ) plotted versus the difference in temperatur e for all of the pilot studies...............................55 4-8 Free chlorine difference of the TRAN S and OPAQ basins (TRANS-OPAQ) plotted versus the difference in temperat ure for baseline parameters..................................56 4-9 Total chlorine residual sampling sets in particular residual ranges for the TRANS and OPAQ basins.....................................................................................................58 4-10 Total chlorine residual difference of the OPAQ and TRANS basins (TRANSOPAQ) plotted versus average UV Radiation over the HDT of the wastewater in the basin for all pilot studies....................................................................................59 4-11 Total chlorine residual difference of the TRANS and OPAQ basins (TRANSOPAQ) plotted versus the difference in temperature between the basins................60 4-12 The TTHM effluent mass concentrati ons for the TRANS and OPAQ basins are shown in range increments.......................................................................................62 4-13 The TTHM effluent molar concentrati ons for the TRANS and OPAQ basins are shown in range increments.......................................................................................62 4-14 Difference in TTHM concentration between the TRANS and OPAQ sides (TRANS-OPAQ) separated into mass concentration ranges...................................64 4-15 Difference in TTHM concentration between the TRANS and OPAQ sides (TRANS-OPAQ) separated into molar concentration ranges..................................64 4-16 Difference in TTHM effluent mass con centration of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus the differe nce in free chlorine residual of the TRANS and OPAQ basins.......................................................................................65

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xii 4-17 Difference in TTHM effluent molar con centration of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus the differe nce in free chlorine residual of the TRANS and OPAQ basins.......................................................................................65 4-18 Difference in TTHM mass effluent con centration between the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus th e difference in free chlorine residual between the TRANS and OPAQ basins for baseline runs.......................................66 4-19 Speciation of the THM formation in th e TRANS effluent on a mass basis sampled at 9 am on August 23, 2004......................................................................................67 4-20 Normalized TTHM effluent mass concen trations for the TRANS and OPAQ basins are shown in range increments.................................................................................69 4-21 Normalized TTHM effluent molar concentrations for the TRANS and OPAQ basins are shown in range increments......................................................................69 4-22 Difference in TTHM concentrati on between the TRANS and OPAQ sides (TRANS-OPAQ) separated into mass concentration ranges...................................70 4-23 Difference in TTHM concentrati on between the TRANS and OPAQ sides (TRANS-OPAQ) separated into molar concentration ranges..................................71 4-24 Difference in normalized TTHM mass concentration of the TRANS and the OPAQ basins (TRANS-OPAQ) plotted versus th e average UV radiation. exposure over the HRT..........................................................................................................................72 4-25 Difference in normalized TTHM molar concentration of the TRANS and the OPAQ basins (TRANS-OPAQ) plotted ve rsus the average UV radiation exposure over the HRT............................................................................................................73 4-26 The HAA(5) effluent mass concentrati ons for the TRANS and OPAQ basins are shown in range increments.......................................................................................75 4-27 The HAA(5) effluent molar concentrat ions for the TRANS and OPAQ basins are shown in range increments.......................................................................................75 4-28 Difference in HAA(5) concentratio n between the TRANS and OPAQ sides (TRANS-OPAQ) separated into mass concentration ranges...................................76 4-29 Difference in HAA(5) concentratio n between the TRANS and OPAQ sides (TRANS-OPAQ) separated into molar concentration ranges..................................76 4-30 Difference in HAA(5) mass concentra tion of the TRANS and the OPAQ basins (TRANS-OPAQ) plotted versus the differe nce in free chlorine residual of the TRANS and OPAQ basins (TRANS-OPAQ)..........................................................77

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xiii 4-31 Difference in HAA(5) molar concentrat ion of the TRANS and the OPAQ basins (TRANS-OPAQ) plotted versus the differe nce in free chlorine residual of the TRANS and OPAQ basins (TRANS-OPAQ)..........................................................78 4-32 Speciation of the HAA(5) formation in the OPAQ effluent on a mass basis sampled at 12 pm on August 30, 2004...................................................................................79 4-33 The HAA(5) effluent mass concentrati ons for the TRANS and OPAQ basins are shown in range increments.......................................................................................81 4-34 The HAA(5) effluent molar concentrat ions for the TRANS and OPAQ basins are shown in range increments.......................................................................................81 4-35 Difference in HAA(5) concentration between the TRANS and OPAQ sides (TRANS-OPAQ) separated into mass concentration ranges...................................82 4-36 Difference in HAA(5) concentration between the TRANS and OPAQ sides (TRANS-OPAQ) separated into molar concentration ranges..................................83 4-37 Difference in HAA(5) effluent mass concentration of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus th e average UV radiation exposure over the HRT..........................................................................................................................84 4-38 Difference in HAA(5) effluent mola r concentration of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus th e average UV radiation exposure over the HRT..........................................................................................................................84 5-1 Free chlorine residual of the UNCOV and COV side effluents separated into concentration ranges.................................................................................................87 5-2 Difference in free chlorine resi dual between the UNCOV and COV sides (UNCOV-COV) separated into concentration ranges..............................................88 5-3 Free chlorine difference of the UNCOV and COV basin sides plotted versus the difference in temperature.........................................................................................89 5-4 Total chlorine residual of the UNCOV and COV side effluents separated into concentration ranges.................................................................................................90 5-5 Total chlorine difference of the UNC OV and COV basin sides plotted versus the difference in temperature.........................................................................................91 5-6 The TTHM effluent mass concentra tions for the UNCOV and COV sides are shown in range increments.......................................................................................92 5-7 The TTHM effluent molar concentra tions for the UNCOV and COV sides are shown in range increments.......................................................................................93

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xiv 5-8 Difference in TTHM concentrati on between the UNCOV and COV sides (UNCOV-COV) separated into mass concentration ranges.....................................94 5-9 Difference in TTHM concentrati on between the UNCOV and COV sides (UNCOV-COV) separated into molar concentration ranges...................................94 5-10 Difference in the TTHM effluent mass concentration between the UNCOV and COV sides (UCOV-COV) plotte d versus the difference in free chlorine residual of the UNCOV and COV sides (UCOV-COV)............................................................95 5-11 Difference in the TTHM effluent mola r concentration between the UNCOV and COV sides (UCOV-COV) plotte d versus the difference in free chlorine residual of the UNCOV and COV sides (UCOV-COV)............................................................96 5-12 Speciation of the TTHM formed in the UNCOV side sampled at 9 am on August 25, 2004....................................................................................................................96 5-13 The TTHM mass concentration instances separated into concentration ranges for the UNCOV and COV side......................................................................................98 5-14 The TTHM molar concentration instances separated into concentration ranges for the UNCOV and COV side......................................................................................99 5-15 Difference in TTHM concentra tion between the UNCOV and COV sides (UNCOV-COV) separated into mass concentration ranges...................................100 5-16 Difference in TTHM concentra tion between the UNCOV and COV sides (UNCOV-COV) separated into molar concentration ranges.................................101 5-17 The HAA(5) effluent mass concentra tions for the UNCOV and COV sides are shown in range increments.....................................................................................102 5-18 The HAA(5) effluent molar concentrat ions for the UNCOV and COV sides are shown in range increments.....................................................................................103 5-19 Difference in HAA(5) concentra tion between the UNCOV and COV sides (UNCOV-COV) separated into mass concentration ranges...................................104 5-20 Difference in HAA(5) concentra tion between the UNCOV and COV sides (UNCOV-COV) separated into molar concentration ranges.................................104 5-21 Difference in HAA(5) effluent mass c oncentration of the UNCOV and COV sides versus the difference in free chlorine residual of the UNCOV and COV sides.....105 5-22 Difference in HAA(5) effluent molar c oncentration of the UNCOV and COV sides versus the difference in free chlorine residual of the UNCOV and COV sides.....106

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xv 5-23 Speciation of the HAA(5) formation in the COV effluent on a mass basis sampled at 12 pm on August 25, 2004.................................................................................107 5-24 The HAA(5) effluent mass concentrati ons for the UNCOV and COV basin sides are shown in range increments...............................................................................109 5-25 The HAA(5) effluent molar concentrat ions for the UNCOV and COV basin sides are shown in range increments...............................................................................109 5-26 Difference in HAA(5) concentration between the UNCOV and COV sides (UNCOV-COV) separated into mass concentration ranges...................................110 5-27 Difference in HAA(5) concentration between the UNCOV and COV sides (UNCOV-COV) separated into molar concentration ranges.................................111 6-1 Total coliform and temperature plotte d against sampling time on July 14, 2004..113 6-2 Total suspended solids and temperature plotted against sampling time on July 14, 2004........................................................................................................................114 6-3 pH and temperature plotted against sampling time on July 14, 2004....................114 6-4 Conductivity and temperature plotted against sampling time on July 14, 2004....115 6-5 The D.O. and temperature plotte d against sampling time on July 14, 2004..........116 B-1 Fluoroscein versus sampling time..........................................................................124 B-2 The F curve.............................................................................................................125 G-1 Trihalomethane GC for spiked sample...................................................................165 G-2 Trihalomethane GC for blank sample....................................................................166 G-3 Trihalomethane GC for field sample......................................................................167 G-4 Haloacetic acid GC for spiked sample...................................................................169 G-5 Haloacetic acid GC for blank sample.....................................................................170 G-6 Haloacetic acid GC for field sample......................................................................170

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xvi Abstract of Dissertation Presen ted to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Engineering COVERING CHLORINE CONTACT BA SINS AT THE KANAPAHA WATER RECLAMATION FACILITY: EFFECT S ON CHLORINE RESIDUAL, DISNIFECTION EFFECTIVENESS, AND DISINFECTION BY-PRODUCT FORMATION By Heather L. Fitzpatrick May 2005 Chair: Paul A. Chadik Major Department: Environmental Engineering Sciences It is commonly understood that sunlight, sp ecifically u ltraviolet (UV) radiation, degrades chlorine and thus reduces chlorine residual in uncovered chlorine contact basins. Its effect on disinfection by-produc t (DBP) formation, however, has not been significantly studied. A pilot and full-scale st udy were performed at the Kanapaha Water Reclamation Facility (KWRF) to investigat e the effect of UV ra diation on chlorine residual, disinfection-by-product formati on, and inactivation of bacteria. For both the pilot and full-scale studies, two chlorine disinfection processes were setup in parallel, for effluent parameter comparisons. One process allowed for the exposure of the wastewater to UV radiation. In the other process an opaque cover was used to prevent solar radiation exposure of th e wastewater during chlo rine disinfection. Preventing UV radiation exposure of wastewat er provided higher chlo rine residuals (on average 0.4 and 0.7 mg/L free chlorine hi gher) for pilot and full-scale averages

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xvii respectively. Extent of chlorine loss fr om UV radiation exposure was directly proportional to the UV exposure intensity during chlorine disinfection. Both processes, with and without UV radiation exposure, provide d adequate total coliform inactivation. To compensate for the difference in efflue nt conditions (such as chlorine residual and temperature), the effluent DBP concentra tions were normalized. In the normalization process, non-exposed effluent DBP concentrations were normalized to UV-exposed effluent DBP concentrations using normaliza tion factors. Normalization factors were calculated from parameter data collected dur ing each sampling run. By preventing UV radiation exposure during chlori ne disinfection, free chlori ne residual was found to be significantly higher, and also th e total trihalomethane effluent concentration was found to be significantly less (on average 17.1 and 7.5 g/L less for normalized concentrations) than for pilot and full-scale averages, respectively. In the full-scale study haloacetic acid (HAA(5)) concentration was significantly less in the process that prevented UV radiation exposure (on average, 39.0 g/L less). Howe ver, the pilot-scale di d not show the same degree of HAA(5) concentration difference; thus, no significant difference was found between the UV radiation exposed and non-exposed processes. Preventing UV radiation, if it does not lessen HAA(5) formation, does not increase formation. Our studies provide evidence contrary to common theory that an increase in free chlorine during chlorination will result in highe r DBP formation. The significance lies in using chlorine disinfection processes where wastewater is covered to prevent UVradiation exposure. When used it could lower the amount of chlorine loss, and help to lower DBP formation.

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1 CHAPTER 1 INTRODUCTION The Kanapaha Water Reclamation Faci lity (KWRF), owned and operated by Gainesville Regional Utilities (GRU), treats wastewater from the west side of Gainesville, Florida, and its outlying areas. The plant uses a modified Ludzak-Ettinger process to treat the wastewater.1 The plant operation promotes biological removal of nitrogen and carbonaceous biological oxyge n demand (CBOD). After the aeration basins, the wastewater moves to the clarifie rs (where solids are removed). Then the wastewater flows through filters (which remove the fine particles that did not settle out in the clarifiers). The wastewater is then collected in a clearw ell, sent to the post-aeration basin, and then disinfec ted in the chlorine contact basins (Figure 1-1). Figure 1-1. Kanapaha Water Recl amation Facility flow diagram.

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2 The plant (Figure 1-2) was recently expanded from a 10 million gallon per day (MGD) to a 14 MGD capacity. A schematic of the wastewater process from filtration through the chlorine contact basi ns is shown in (Figure 1-3). Figure 1-2. Overhead layout of the KWRF. Figure 1-3. Wastewater process fr om filtration through chlorination. 6 Filters Post-Aeration Basins North Chlorination Basin South Chlorination Basin

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3 From the clarifiers, the wastewater is sent to six filters setup in parallel. The filter effluents combine into a single 100,000-gallon cl earwell. Chlorine gas is injected into the pipe as the wastewater flows from the pos t-aeration basin to the first of two chlorine contact basins, to begin the di sinfection stage of the treatment process. The two chlorine contact basins are setup in series (the Nort h and the South chlorine contact basins). The first chlorine contact basin (the North basin) with a volume of 0.16 MG, is part of the original plant. The wastewat er then flows to a second chlo rine contact basin (the South basin) with a volume of 0.57 MG. The Sout h basin was added after the original plant was built, to increase treatment capacity. A previous study at the KWRF determined that the North and South basins t ogether model as 60 tanks-in-se ries while the North basin models as 100 tanks-in-series separately.2 As stated, the KWRF relies on chlorine to disinfect the wastewater. Enough chlorine gas is injected to create sufficient free chlorine to meet the chlorine demand of the wastewater and leave enough effluent re sidual to meet the standards set by the Environmental Protection Agency (EPA) a nd upheld by the Florida Department of Environmental Protection (FDEP). According to the KWRF permit, the effluent must have at least a 1 mg/L Cl2 free chlorine residual. In the chlorination process at the KWRF, the contact basins are open to the environment; allowing the wastewater to be exposed to UV radiation from sunlight. The UV radiation acts as a ca talyst to reduce the free chlorine (Equation 1-1). This reduction l eads to an appreciable amount of chlorine loss due to UV radiation exposure. 22 2 2 O Cl H HOClUV (1-1)

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4 Since the KWRF injects treated wastewater into deep wells in the Floridan aquifer (a drinking water source), and is used in reus e applications, the finished wastewater must meet EPA and DEP permit requirements. Disinfection by-product formation is of increasing concern, since these by-products are linked to harmful health effects. Pregeant1 using wastewater from the KWRF show ed a positive correlation between free chlorine residual and THM formation. As the chlorine residual was increased the THM concentration formed also increased, given that there were THM precursors left in the wastewater to react. 1 In a previous study performed by the Integrated Product and Process Design (IPPD) team sponsored by Gainesvill e Regional Utilities (GRU) in 2001-2002 the chlorine loss at the KWRF was investigated.2 Most chlorine loss was assumed to result from chlorine decay by ultraviolet (UV) irradiation (Equation 1-1). Thus it was suggested that covering the basin would decrease chlorine loss caused by this mechanism. The IPPD study provided good insight into the hydrodynamic behavior of the treated wastewater as to flows through the ch lorine contact basins and the disinfection process at the KWRF. The study comprises tw o days worth of data compilation, March 19th and January 24th, for chlorine concentration, total trihalomethane (TTHM) concentration, and the volume of water irradi ated by sunlight. In the study one side of the chlorine contact basin was covered with a polypropylene ta rp while the other side was left open. The covered side of the basi n had a higher chlorine residual than the uncovered basin verifying a definite correlati on between sunlight exposure and chlorine degradation.2 The study also showed that as the s unlight intensity increased from winter

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5 to summer months, the chlorine loss within the uncovered basin increases also. The study provided some unexpected results: the tota l trihalomethane (TTH M) concentrations were actually lower in the covered basin than the control, or uncovered basin.2 This phenomenon is opposite of that found in the Pregeant1 study and is contrary to common theory, where a higher residual produced a highe r trihalomethane (THM) concentration. One aspect of this study was to further investigate the phenome non found by the IPPD team. In order to further ascertain the impact of solar radiation, ultraviolet (UV) and visible radiation, on the chlori nation process in the wastewater treatment plant, a research plan was proposed to and accepted by the Gain esville Regional Utilit ies. One focus of this study is the UV radiation catalysis of th e oxidation reaction of water by chlorine to form oxygen and the chloride ion, Equation 1-1. Also, this study reviews the impact of UV radiation and global horizon tal radiation on bacterial in activation and disinfection byproduct (DBP) formation. This study involves both a pilot and full-sc ale investigation of the chlorination process at the KWRF to determine to what exte nt solar radiation affects chlorine residual, disinfection effectiveness, and disi nfection by-product formation. Pilot Study The pilot basin study involved two pilot ba sins scaled after the KWRF chlorine contact basins. One basin was equipped w ith an opaque acrylic cover to block solar radiation from entering and coming in contac t with the water during chlorination. The second basin was equipped with an UV transmitting clear acrylic, or UV-TRANS, cover that allowed solar radiation, both UV and visi ble radiation, to come in contact with the water during chlorination.

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6 The feed water for the pilot basins had gone through the plant filters but was not chlorinated by the plant chlorination system. Th e feed water to the pilot basins was first dosed with a known concentration of chlorine (NaOCl), and then split into two equal streams before entering the pilot basins. The pilot basin study makes it possible to keep flow rate and chlorine dosage constant which was not possible in the full-scal e study. It also en abled the control and variation of flow rates, pH levels, and chlorine dose to determine the extent of their involvement in the effects of solar radiation on the chlorination process and water quality parameters. KWRF average, minimum, and maximum chlo rine dosage, pH, and flow rates were used in this phase of the st udy. The KWRFs effluent wast ewater had a total chlorine residual minimum of 1.4 mg/L as Cl2, an average of 2.8 mg/L as Cl2, and a maximum of 4.8 mg/L as Cl2 according to data provided by GRU for 2003. In the pilot study the average plant value was used as the pilot baseline value while chlorine dosing that produces water with minimum and maximum residual values was also tested. The influent pH, or raw pH, experienced at the KWRF does not vary much from a neutral pH, around 7. Thus, for this experiment a pH of 7 was used as the baseline value while pH values of 6 and 8 were also tested to determ ine the influence of pH on the pilot system. In the pilot study a baseline hydraulic reten tion time (HRT) of 2.75 h was used. A longer HRT of 3.81 hrs was also tested to amplif y the effect of radiation on water quality parameters in this study. The KWRF averag e and maximum HRT in the chlorine contact basins is approximately 1.8 and 4.4 h, respectively.

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7 Full-Scale Study A full-scale study was also implemented to further investigate th e effect of solar radiation on the disinfection ch lorination stage of the wastew ater treatment under normal operating conditions. The full-scale study wa s performed on the North basin and did not include the south basin. In the North basin the flow is split imme diately into two parallel streams after it enters the basin. Chlorine gas is injected in to the pipe that transfers the wastewater from the post-aeration basin to the North chlorine contact basin. In the full-scale study one half of the basin was covered with polypr opylene tarps and the other half was left uncovered. As in the pilot-scale study the e ffect of UV radiation on the chlorine residual, disinfection effectiveness, and disinfection by-product formation was investigated. The full-scale study was performed to determin e the effect of covering the basin under standard plant chlorination procedures so no sp ecial adjustments were made. Just as in the pilot study, the UV radiation impact on ch lorine residual, disinfection effectiveness, and DBP formation was examined. Clarifier Chlorine Addition The KWRF has recently installed chlori ne injection pipes in the clarifiers (Figure 1-4). The chlorine addition was impl emented to reduce algae growth in the weirs of the clarifiers. The chlorine addition at th e clarifiers, however, would also result in the formation of DBP and could have a lingering effect on chlorine residual and demand. This would lead to inaccuracies in data coll ected during the pilot a nd full-scale studies. In order to prevent the interference caused by the chlorine dosing of the clarifiers the chlorine dosing of the clarifiers was ceased at 4 pm the day prior to sampling and remained turned off until 4 pm the day of the testing. Sampling and analysis of the pilot

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8 basin feed wastewater indicated that ceasing the addition of ch lorine in the clarifiers at 4:00 pm ensured that the chlorine residual and TTHM concentrations were below detection at 9:00 am the next morning. Figure 1-4. Chlorine ad dition at the clarifiers.

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9 CHAPTER 2 REVIEW OF LITERATURE Nitrification/Denitrification Nitrogen is incorporated into all living thi ngs, and is also present in the atmosphere. Nitrogen is taken from the atmosphere by ni trogen-fixing bacteria and through the action of electrical discharge during storms.3,4 Although nitrogen is necessary for life, if too much nitrogen is fed into a receiving body of water an over production of algae and other aquatic life can occur, or eutrophication.4,5 Also, organic nitrogen compounds and ammonia exert a chlorine demand. A higher ch lorine dose would be required to achieve adequate disinfection if or ganic nitrogen and ammonia we re not removed prior to disinfection.6 Domestic raw wastewater contains mostly organic and ammonia nitrogen, or Kjeldahl nitrogen.5 One of the major treatment processes at the KWRF is the use of biological nitrification and denitrificati on to remove nitrogen from the wastewater. The autotrophic nitrifying bacteria group, Nitrosomonas under aerobic conditions oxidizes ammonia and ammonium to form nitrite (Equation 2-1).3,4,5,7 Nitrite can then be oxidized further by the bacteria group Nitrobacter to form nitrate (Equation 2-2).3,4,5,7 The aerobic oxidation of organic nitrogen to inorganic nitrogen, nitrific ation, is carried out in the aeration basins and also in the newly instal led carousel at the KWRF. H O H NO O NHas Nitrosomon4 2 2 3 22 2 2 3 (2-1) 3 2 22 2 NO O NOr Nitrobacte (2-2)

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10 After the ammonia and ammonium are conve rted to nitrite and nitrate it can be reduced to nitrogen ga s by facultative anaerobic bacteria, such as Pseudmonas .3,5,7 It is presumed that any nitrate present is reduced to nitrite and then to nitrogen gas. The overall denitrification is shown in (Equation 2-3). At the KWRF the reduction of nitrite and nitrate to nitrogen gas, denitrification, takes place in the anoxic basins and in the newly installed carousel. ) ( 6 7 5 3 5 62 2 2 3 3OH O H CO N OH CH NObacteria (2-3) Chlorine Disinfection Disinfection of wastewater can be dated back to the late 1800s with the use of chlorinated lime for odor control and the tr eatment of fecal material from hospitals.8 Because of the known health problems inflic ted on humans by microbial organisms, disinfection of wastewater ha s become a mainstream proce dure. The disinfection of wastewater helps prevent bacterial contamina tion of drinking water sources, thus, aiding in the control of waterborne diseases. Ch lorine is one of the most widely used disinfectants for both potable and wastewater treatment because of its relatively low cost and effectiveness as a disinfectant wh en compared to other alternatives.6,8 At atmospheric pressure and room temperature chlorine exists as a poisonous yellow gas.8 For the purpose of water and wastewater treatm ent chlorine gas is pressurized as a dry, liquefied gas and is stored in steel cylinders to make it easier to store and apply. During chlorine disinfection three types of reactions can occur: oxidation, addition, and substitution.9

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11 Free Chlorine In wastewater the chlorine gas is adde d to water and hydrolyzes to hypochlorus acid (HOCl) and the hypochlorite ion (OCl-) (Equations 2-4 and 2-5).4,6,7 Together, HOCl and OClare called free chlorine. Cl H HOCl O H Cl2 2 (2-4) H OCl HOCl (2-5) Studies show HOCl to be a more efficien t disinfectant and a stronger oxidant than OClhence HOCl is the desired species when disinfecting.8,10 The pKa for HOCl is 7.5at 25 C, thus, at a pH of 7.5 HOCl and OClexist in equal concentrations. If the pH is below 7.5 the predominant species is HOCl while at a pH above 7.5 OClpredominates.4 The percentage of free chlorine as HOCl and OClis dependent on the pH and temperature conditions (Figure 2-1).4 Most wastewater treatment facilities operate in a range where the HOCl species is prevalent t hus increasing their disinfection efficiency and lowering the chlorine dose re quired to achieve disinfection.6 Figure 2-1. Percent of free chlorine compound (HOCl and OCl-) versus pH.

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12 Chlorine can react with many chemicals, inorganic and organic, present in the wastewater stream. The amount of chlorine dissipated during these reactions is referred to as the chlorine demand the wastewater po ssesses and dictate the amount of chlorine that must be added to achieve a specif ic chlorine residual and good disinfection. Combined Chlorine In the presence of ammonia (NH3) the free chlorine species HOCl will react to form chloramines that consist of monochlroamine (NH2Cl), dichloriamine (NHCl2), and nitrogen trichloride (NCl3).4,6,10 (Equations 2-6, 2-7, and 2-8). O H Cl NH HOCl NH2 2 3 (2-6) O H NHCl HOCl Cl NH2 2 2 (2-7) O H NCl HOCl NHCl2 3 2 (2-8) Chloramines have the capacity to disinfect wastewater but are not as effective as free chlorine. All domestic wastewaters cont ain organic nitrogen compounds, including amino acids and proteins.6,8 Chlorine reacts with these organic nitrogen compounds to form organic chloramines. Though these organic chloramines contribute to the combined chlorine concentration they have no known disinf ecting capability.6,8 Organic chloramines show up as combined chlorine in the iodometric and DPD chlorine residual methods.8 The speciation of inorganic chloramine s is more related to the pH of the wastewater and the chlorine to ammonia mola r ratio and not as much on the contact time of ammonia and HOCl.6,8 Under normal operating conditions monochloramine predominates. As the pH decreases below neutral (pH=7) and as the Cl2:N mass ratio

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13 value increases from 3:1 up to 7:1 the formati on of dichloramine is favored. As the pH continues to decrease nitr ogen trichloride will form.6 The chloramine hydrolysis reactions will re sult in the release of ammonia, which could play a role in nitrif ication (i.e. formation of NO3 -). The decomposition of dichloramine increases as the pH and alkalinity increase.6,8 This makes dichloramine less stable than monochloramine under normal wast ewater conditions. The decomposition of monochloramine occurs in essentially two r eactions the first bei ng hydrolysis and the following being the acid catalyzed reaction with the generated free chlorine and results in the formation of dichloramine and ammonia in the wastewater.6,8 Break-Point Chlorination In order to form HOCl in the presence of ammonia or other organic nitrogen enough Cl2 gas must be added to reach and pass what is called the breakpoint (Figure 2-2).4 The process is therefore termed breakpoint chlorination. Beyond the breakpoint free chlorine is dominant and ma kes up a large percentage of the total chlorine. However, also present beyond the breakpoint are what are termed irreducible or nuisance chlorine residua ls that show up in total chlorine residual measurements but do not have the disinfecting capabil ities that free chlorine possesses.6 The organic chloramines and, if present, nitrogen trichlor ide contribute to the irreducible chlorine residual.

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14 Figure 2-2. Breakpoint chlorination: Speci es of chlorine residuals present during chlorination when ammonia is present. Compounds other than ammonia and orga nic nitrogen compounds can exert a chlorine demand; the demand exerted is related to their concentration in the wastewater. For example, inorganic substances such as the sulfide, sulfite, nitrite, iron (II), and manganese (II) ions all can exert a chlorine demand.8 If ammonia is present in the wastewater stream the demand these species exert is reduced and sometimes even eliminated.8 Contact Time One of the most important parameters in chlorine disinfection is contact time. Inactivation of pathogens increases with an increase in contact ti me. The disinfection effectiveness is expressed as Ct; where C is the disinfectant concentr ation, and t is the contact time necessary to in activate the desirable amount of the pathogenic organism.3,7 In essence, the longer the pr ovided contact time, the subs equently less chlorine is

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15 necessary to achieve sufficient disinfection. Based on a comprehensive pilot plant study Collins et al. developed an equation to determine bacterial inactivation at wastewater treatment plants (Equation 2-9).6 The equation fits best where good initial mixing followed by plug flow conditions occur. The wastewater at the KWRF is first filtered prior to chlorine disinfection. Accordingl y, the initial bacterial concentration would probably range from 3,000 to 10,000 coliforms per 100 mL.6 3] 23 0 1 [ ct y yo (2-9) yo = initial bacterial concentration prior to chlorination y = bacterial concentration at end of c ontact chamber or at time T in minutes c = initial chlorine concentration t = contact time in minutes The model can be used to predict bacter ial inactivation in wastewater given the HRT provided in the disinfection chamber. As the model demonstrates, the disinfection of wastewater with chlorine depends greatly on chlorine conc entration addition as well as contact time. The KWRF uses chlorine cont act basins, described ear lier, to provide the contact time necessary to inactiv ate the indicator organisms, total and fecal coliforms. As wastewater chlorine demand changes the chlorine addition is altered to provide adequate disinfection. Disinfection By-Product Formation Though the chlorination of wastewater is be neficial in inactivating disease-causing organisms it can also cause the forma tion of potentially harmful and carcinogenic compounds. According to epidemiological st udies there is a correlation between water chlorination and rectal an d bladder cancer cases.11 When organic compounds or precursors such as natural organic matter (NOM), humic and fulvic acids, are present

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16 during chlorination they may react with the fr ee chlorine to form what are collectively called disinfection-by-products (DBPs).4 The main concern for public health su rrounds the formation of DBPs known as trihalomethanes (THMs) and ha loacetic acids (HAAs). B ecause of the public health concern surrounding these compounds, the federal Environmental Protection Agency (EPA) has imposed a maximum concentration al lowed in drinking water. As of 2004 the regulatory drinking water MCL standards for TTHM and HAA(5) are 80 g/L and 60 g/L, respectively.12 THM species include chloroform (CHCl3), a known human carcinogen, bromoform (CHBr3), bromodichlormethane (CHBrCl2), and dibromochlormethane (CHBr2Cl) (Figure 2-3). The five HAA species that are currently under regulation include monochloroacetic acid (MCAA), monobromoacetic acid (MBAA), dichloroacetic acid (DCAA), dibrom oacetic acid (DBAA), and trichloroacetic acid (TCAA) (Figure 2-4).8,13 There are several factors that can affect the formation of these DBPs, such as, temperature, pH, precurs or concentration, chlorine dose, contact time, and bromide concentration. Figure 2-3. The THM species. Chloroform H Cl C Cl Cl Bromoform H Br C Br Br Bromodichloromethane H Cl C Cl Br Dibromochloromethane H Cl C Br Br

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17 Figure 2-4. The HAA(5) species. The natural organic matter (NOM) present in wastewater is a precursor for DBPs during chlorination.11 The NOM is measured as dissolved organic carbon (DOC) or total organic carbon (TOC). NOM consists largel y of aromatic compounds, thus, studies have found that aromaticity was a good surrogate for the prediction of DBP formation.14,15 In general, as the NOM concentration increases the DBP formation during chlorination also increases. This increase in DBP formation is the result of an increase in these DBP precursors but also is due to the increas e in chlorine demand exerted by the NOM.11 With the increase in chlorine demand a higher chlorine dose is necessary to maintain the required chlorine residual. The increase in chlo rine dose will result in an increase in DBP formation. In one study, lower molecular weight NOM compounds resulted in a higher H Cl O H C C OH Monochloroacetic acid (MCAA) Br H O H C C OH Monobromoacetic acid (MBAA) Cl Cl O H C C OH Dichloroacetic acid (DCAA) Dibromoacetic acid (DBAA) Br O H C C OH Br Trichloroacetic acid (TCAA) Cl Cl O C C OH Cl

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18 total trihalomethane (TTHM) yield.16 In general, as the molecular weight of the NOM present in the water or wastewater decreased the TTHM yield increased.16 In one study, findings showed that when chlorine is a pplied to water containing NOM the hydrophobic NOM fraction resulted in a higher DBP fo rmation than the equivalent hydrophilic fraction.17 Through the oxidation of NOM with chlorine intermed iate compounds may form.11 These intermediates are further oxidized by chlorine, or bromine, to form DBPs. Generally, as precursor concentration, NOM increases so does the DBP production, but it will tend to plateau and even decline after the residual chlorine is exhausted.1 The apparent decrease in THM production shown in the study done by Pregeant et al. which was carried out at high precursor concentr ations was hypothesized to result from the predominance of THM intermediates when excess precursors existed.1 The reactions that result in the direct formation of DBP tend to occur more quickly and form earlier during the chlorination process than those that have an intermediate step.11 Environmental factors such as bromide concentration and the amount of natural organic matter affect the amount of DBPs fo rmed during chlorination. Chlorine oxidizes the bromide ion forming hypobromous acid (HOBr) and hyprobromite (OBr-) ion, depending on the pH.18 The hypobromous acid and, to a lesser extent, the hypobromite ion react with DBP precursors by oxidation a nd substitution reactions to form brominated DBPs.11,18 As the bromide concentration incr eases the chlorinated HAA concentration decreases.18 Given the same chlorine dosing, the a ddition of the bromide ion results in an increase in the HAA concentration. Studies have also shown that the hypobromous acid oxidizes NOM more readily than hypochlorous acid.11,18,19 In one study it was determined that bromine reacted ten times faster with NOM isolates than chlorine.19 The

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19 presence of the bromide ion (Br-) in the wastewater stream can greatly alter the speciation and formation of THM and HAA during chlorination.18 The free chlorine oxidizes the Brto hypobromous acid (HOBr) (Equation 2-10); HOBr will ionize as the pH increases to OBr-. Cl HOBr Br HOCl (2-10) The bromide ion can have a substantial e ffect on the mass concentration of DBP as bromine has a greater molecular weight, 80, than chlorine, 35.5. The DBPs formed when HOBr reacts with organic precursors have a higher molecular weight than those with chlorine. This is a concern as the EPA MCLs for DBP are on a mass basis, g/L, and not a molar basis. As the temperature of the wastewater increases so does the HAA and THM concentrations. The pH has a variable eff ect on the DBP concentration. Studies have found that as the pH is increased from 6 to 8, the THM formation also increased but resulted in a lower HAA formation.11,17,20 When the pH is lowered from a neutral pH to 6 the HAA formation increased.11,17 A longer chlorine contact time will result in a higher DBP formation because more time is allowed for chlorine to react with NOM. An increase in contact time will allow those reactions that require intermediate step s more time to react to completion. The formation of THM increases as time allowed fo r reaction with free chlorine increases, or the contact time, though the rate of formation is not constant. The chlorine dose has a similar effect on DBP formation as the dose increases so does the DBP concentration

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20 sometimes reaching a plateau.1 The chlorine dose can also affect the speciation of DBP as the dose increases the ratio of THM to tota l halogenated DBP ratio also increases. Modeling of DBP formation. Disinfection by-product formation modeling helps to predict the amount of DBP formed during the chlori nation of a feed water if the necessary parameters are known. The EPA has developed disinfection/disinfection byproduct rule models to pred ict THM and HAA formation to determine operational and economic impacts of setting new MCLs.13 The models used to predict THMs were developed by Malcome Pirnie and models us ed to predict HAAs were developed by Dr. Charles Haas, contracted by the AWWA D/DBP Technical Advisory Workgroup (TAW).13 Since the KWRF provides tertiary wastewater treatment where additional solids are removed by the six media filters the EPA models developed for drinking water are applicable.. AWWA contracted Montgomery Watson to develop new model equations for individual THM and HAA species and publis hed the findings in a March 1993 report.13 Environmental parameters used in the forma tion of the model equations include bromide concentration, TOC, ultraviolet light absorb ance at 254 nm, temperature, chlorine dose, pH, and reaction time. Using the basic equation (Equation 2-11)13, as a guideline the coefficients for each environmental variable were determined through a step-wise regression model procedure for individual THM and HAA species. g f e d c b aTIME UV BR DOSE CL TEMP pH TOC k DBP ) ( ) 254 ( ) ( ) 2 ( ) ( ) ( ) ( (2-11) k, a, b, c, d, e, f, and g are empirical constants

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21 The program STATVIEW was used in the step-wise regr ession procedure to determine the coefficients. Another study showed that if the data is available nitrate, calcium, and alkalinity could be used in the prediction of THM formation.21 Chloroform made up the majority of the TTHM concentrations in this study and thus the AWWA model equation for chloroform (Equation 2-12) 13 was used to normalize the sampling sets; an explanation of the nor malization method used is in the Materials and Methods section. 269 0 874 0 254 404 0 1 561 0 2 018 1 161 1 329 0 3] 01 0 [ ] [ ] [ 064 0 t UV Br Dose Cl T pH TOC CHCl (2-12) 1 254 1 2 2 3/ / / ) ( ) ( / cm UV L mg Br Cl L mg Dose Cl L mg TOC hrs Time t C e Temperatur T L g CHCl The model predicted chloroform concentr ation is plotted versus the observed chloroform concentration for the whole model development database from the March 1993 AWWA report (Figure 2-5).13 A perfect prediction would re sult in a slope of 1, the farther from the perfect prediction line the less accurate the prediction.13 The prediction versus the actual chloroform coincides bett er from 0 to 200 g/L than concentrations greater than 200 g/L. Typical wastewater TTHM concentrations do not exceed 200 g/L.13

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22 Figure 2-5. Predicted versus the observed co ncentration of CHCl3 for the entire model development database from the 1993 AWWA report. The AWWA model equation for dichlo roacetic acid (DCAA) was used to normalize HAA(5) concentrations of the sampling sets, an explanation of the normalization method is in the Materials and Methods section. The relationship of the variable environmental parameters in the formation of the HAA(5) species DCAA is shown in (Equation 2-13).13 726 0 239 0 568 0 1 480 0 2 665 0 291 0] 254 [ ] 01 0 [ ] [ ] [ ] [ 605 0 UV t Br Dose Cl Temp TOC DCAA (2-13) C Temp L mg Br Cl L mg Dose Cl L mg TOC hrs Time t L g DCAA / / / ) ( /1 2 2

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23 The model predicted DCAA concentration was plotted versus the observed DCAA concentration for the whole model development database from the March 1993 AWWA report (Figure 2-6).13 The predicted concentrations do not correlate perfectly with the observed values, however, the points lie close to the perfect prediction line, slope =1, and is sufficiently accurate.13 Figure 2-6. Predicted versus the observed concentration of DCAA for the entire model development database from the 1993 AWWA report. Sunlight/UV Irradiation At the KWRF, chlorine disinfection of wa stewater occurs in an open flow-through basin. This allows sunlight to come in contact with the chlorinated water. Aqueous chlorine is unstable when exposed to sunli ght, which results in th e degradation of free chlorine within the wastewater stream (Equation 2-14).7 22 2 2 O Cl H HOClUV (2-14)

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24 The cost of this loss can add up since more chlorine is needed to achieve the desired disinfection. In the 2002 IPPD st udy the chlorine residua l was substantially greater in a covered basin ve rsus an exposed basin given the same initial chlorine dose and contact time.10 The amount of chlorine loss to solar irradiation depends on the length of exposure and the volume of wastewater irra diated, which in turn depends on the angle of incidence between the sun and chlorine cont act basin and the turbidity. In most cases the photodecay of HOCl is assumed to follow a first-order reaction.22 The ultraviolet (UV) radiation degrades chlorine and is that portion of the electromagnetic spectrum between wavelengths of 100 and 400 nm. UV radiation is then divided into vacuum UV (100-200 nm), UV-C (200-280 nm), UV-B (280-320 nm), and UV-A (320-400 nm).22 The transmittance of solar radiation th rough a medium is dependent on several factors including the type (e.g. glass) a nd thickness of the medium, the angle of incidence, and the specific wa velength or bands of radiati on. Pyrex glass (borosilicate type), is opaque to UV-B radiation and has maximum transmission at 340 nm and higher, this is the UV-A portion of the spectrum.22 Plastics, such as, polys tyrene (i.e. Lucite) and methylmethacylate (i.e. Plexiglass) can have a higher radiation transmittance than glass at wavelengths greater than 290 nm. Thus, these plastic materials have greater transmission of germicidal solar radiation at wavelengths from 300 to 400 nm.22 In this study an acrylic UV-transparent plastic was used as it allowed solar radiation, UV and global, to come in contact with the wastewater dur ing chlorination and was cost effective. The sunlight inactivation of microorganisms in water and wastewater is proportional to the sunlight intensity, contact surface area, and atmospheric temperature

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25 and is inversely proportional to water depth.23,24,25 Sunlight inactivati on, or disinfection, is also dependant on the bacterial contamination load of the water, the more bacteria to inactivate the longer the necessary exposure time.24 Turbidity and color also play a big role in the inactivation of micr oorganisms through sunlight exposure.24,25 In one study, it was reported that turbidity inversely affect ed the kill rate for all bacteria tested.23 In general, a higher turbidity will require a l onger sunlight exposure to obtain adequate disinfection.23 Besides the inactivation of microorganisms, absorption of sunli ght also tends to increase the temperature of the exposed wate r. At higher water temperatures, greater than 70C, the bacterial inactivation is greate r than at lower water temperatures, less than 65 C.25,26 Studies have determined through the implementation of dark experiments runs, chlorine dosing experiments that are perf ormed with no sunlight exposure, that solar radiation was the primary di sinfecting factor when the water temperature was 9 to 26C.27,28 According to sensitivity studies, f ecal coliform were the most sensitive microorganisms to sunlight inactivation among those microorganism tested, such as, somatic coliphages and bacteriaphages.26,28,29 One concern of covering the chlorination basin is the removal of the natural disinfecting property of sunlight. Though the chlorine dose will be higher in the covered basin this may or may not coincide with hi gher coliform inactivation as the contribution of sunlight to the wastewater disinfection pr ocess has yet to be qua ntified. The extent sunlight will affect the chlorination proce ss depends on how much sunlight reaches the water in the basin. The differe nt wavelengths within the sunl ight spectrum have different coliform inactivation potentials. As explained in Acra et al. the inactivation of coliform

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26 bacteria decreases exponentially as the wave length of light increas es from 260 nm to 850 nm.22 Thus, the destruction of coliforms, and expectantly other bacteria too, is most efficient at the lower wavelengths (260 nm to 350 nm), and is least efficient at the higher wavelengths (550 nm to 850 nm). Thus, th e UV-B and UV-A portions of the spectrum possess the greatest inactivation potential.22 Wavelengths below 290 nm should not be included when considering solar radiation, as they do not reach the surface.22 This phenomenon is due to diffusion, or scattering, and absorption of li ght before it reaches the surface.22 The solar UV-A intensity changes as the Earths angle of tilt changes. The highest intensity of UV-A occurs during the summer months while the peak maximum and minimum occur at the summer and winter solstice, respectively.22 Thus, the inactivation of coliforms by sunlight is greater during the summer months Also, chlorine loss is expected to be highest during the summer as the degradation of chlorine is catalyzed by UV light.

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27 CHAPTER 3 MATERIALS AND METHODS Measured Parameters Global Solar Radiation Global solar radiation, or light, between 285 and 2800 nm wavelength was measured using a Black and White Pyra nometer (8-48) manufactured by Eppley Laboratory, Newport, Rhode Island. Ultraviolet Radiation Ultraviolet radiation with a wavelength of 295 to 385 nm was measured using a Total Ultraviolet Radiometer (TUVR) manuf actured by Eppley Laboratory, Newport, Rhode Island. The radiometer and pyranometer were located on location at the KWRF approximately 0.5 m from the pilot basin system. Radiation measurements for both instruments were recorded every 5 minutes throughout the pilot and full-scale runs. The millivolt outputs from the pyranometer and radiometer were stored in a Campbell Scientific CR510 datalogger. The datalogger was powered using th e Campbell Scientific PS100 Power Supply and Charging Regulator. Using the Campbell Scientific SC32B Optically Isolated RS-232 inte rface the data were transferre d from the datalogger to the laptop computer for analysis. The radiomet er, pyranometer, and datalogger setup is shown in (Figure 3-1).

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28 Figure 3-1. Radiometer, pyra nometer, and datalogger setup. Total and Free Chlorine Residual Both total and free chlorine residual were measured in the inlet and effluent samples for the pilot and full-scale experime nts. The DPD method was used with the HACH DR 2000 Spectrophotometer to determine total and free chlori ne residual in the field. The method was equivalent to the US EPA 330.5 method for wastewater, standard method 8167 for total chlorine and standard method 8021 for free chlorine residual. A sample of wastewater was co llected from the respective sampling area and diluted using deionized water when necessary. According to a chlorine residual test performed on June 10, 2004 the deionized water resulted in no ch lorine residual addition nor a chlorine demand. The HACH DR 2000 spectrophotometer wave length calibration was performed on June 10, 2004 and again on August 6, 2004. In both calibration ev ents the wavelength did not need to be adjusted demonstrating th at the spectrophotometer was still in line and CR510 Datalogger Radiometer Pyranometer

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29 was giving accurate readings. A chlorine residual calib ration was also preformed on those days, using chlorine free glassware, by comparing the residual concentration reading from the DR2000 field spectrophot ometer to that of the lab HACH DR2010 spectrophotometer, no difference was observed between the two readings. Total Suspended Solids The KWRF lab uses EPA method 160.2 to measure the total suspended solid concentrations in the effluent wastewater samples. Samples were taken from the inlet and the two effluents for the pilot and full-sc ale studies. Plastic one-gallon containers were used in the collection of samples for the total suspended solids analysis. Directly after collection the samples were taken to the KWRF lab and refrigerated until analyzed, the time between collection and placement in the refrigerator did not exceed 15 minutes. Total Coliform The KWRF lab uses Standard Method 9222B to analyze th e wastewater samples to determine the total coliform population of the samples. Total coliform counts were measured in lieu of fecal colif orm since fecal coliform are more easily inactivated than other species that make up total coliforms. Fecal coliform are also more easily damaged by UV radiation than other total coliform species. Samples were taken from the inlet and the two effluents for the pilot and full-scale studies. Glass 1 L Wh atman containers and 100 mL plastic containers, for pilot basin inlet samples (pre-c hlorination), were autoclaved and supplied by the KWRF lab a nd used in the collection of wastewater samples for the total coliform analysis. Directly after collection the samples were taken to the KWRF lab and refrigerated until analyzed, the time between collection and placement in the refrigerator did not exceed 15 minutes.

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30 Trihalomethane (THM) The THM speciation and concentration wa s determined following the EPA Method 624, method for organic chemical analys is of municipal and industrial waste.30 Dr. M. Booth performed the THM sample analyses at the University of Flor ida, Department of Environmental Engineering and Sciences Anal ytical Sciences Lab (ASL). The following materials were used in the sampling stage of the THM analysis: 40 mL amber glass VOA sampling vials Teflon septa Sodium Thiosulfate, to quench chlorine residual Tekmar 3100 Purge-and-Trap Concentrator Finnigan Trace 2000 GC/MS Gas-Chromatograph: Restek Rtx-VMS cap illary column, 30m x 0.32 mm I.D., 1.8 m film thickness Mass Spectrometer: Electron Ionization, 34 amu to 280 amu in 0.4 seconds Sample GC/MS curves as well as THM analysis conditions can be found in Appendix G. For the pilot basin system the THM samples were collected at the effluent. Both the inlet and effluent samples were collected for the full-scale system. The samples were stored on ice directly af ter collection and transferred to the ASL for analysis at the end of each sampling day. The samples were then stored in the lab refrigerator until they were analyzed. In all instan ces, the samples were analyzed within the suggested holding period. Haloacetic Acid (HAA) The HAA speciation and concentration was determined following the EPA Method 552.2, determination of haloacetic acid a nd dalapon in drinking water by liquid-liquid extraction, derivation and gas chromat ography with electron capture detection.31 The derivation and methylation of the HAA sample s were performed at the University of

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31 Florida ASL. The following materials were used in the sampling stage of the HAA analysis: 40 mL amber glass VOA sampling vials Teflon septa Ammonium Chloride, to que nch chlorine residual Hewlett-Packard 5890 Series II GC/ECD Gas-Chromatograph: Restek DB5MS Cap illary Column, 30m x 0.25 mm I.D., 0.25 um film thickness Sample GC/ECD curves as well as HAA analysis conditions can be found in Appendix G. For the pilot basin system the HA A samples were collecte d at the effluent. Both the inlet and effluent samples were collected for the full-scale system. The samples were stored on ice directly af ter collection and transferred to the ASL for analysis at the end of each sampling day. The samples were then stored in the lab refrigerator until they were analyzed. The methylation procedure was performed within 3 days of sample collection, well within the suggested holding time. Dr. M. Booth then analyzed the methylated samples within the suggested holding period. pH The pH of the feed and effluent stream s for the pilot and full-scale studies was measured using the Orion model 290A pH me ter with the 9157BN-thermo temperature compensating probe. Every morning, prior to sampling, the pH meter was calibrated using 3-point calibration with pH buffer solutions 4, 7, and 10. Conductivity The conductivity of the feed and effluent streams for the pilot and full-scale studies was measured using the Fisher Scientific 09-328 Automatic Temperature Compensation Conductivity probe. The conductivity probe me ter was calibrated every morning using a 0.01 N KCl solution.

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32 Dissolved Oxygen The dissolved oxygen (DO) of the feed and effluent streams for the pilot and fullscale studies was measured using the YSI Dissolved Oxygen/Temperature Meter (YSI Model 57/ YSI 5739). Every morning the probe was checked for air bubbles from membrane weakening. If air bubbles were pr esent then the probe solution and membrane were replaced. Sampling Wastewater sampling from the respective locat ion (i.e. inlet or effluent in the pilot or full-scale system) and parameter was collect ed in a manor to limit aeration while also obtaining a good representative sample. The parameters that were analyzed by the KWRF lab, TSS and total coliform, were stored in the lab refrigerator directly after a sampling. The KWRF samples were put in the refrigerator within 15 minutes of collection. Those samples that were analyzed at the University of Florida Department of Environmental Engineering and Sciences ASL, THM and HAA, were stored on ice after collection and then transported to the lab after the last sample of the day was collected. The samples were then transferred to a refrig erator located in the ASL where they were then analyzed using their respective method. Pilot Scale System The plant chlorine contact basins, North and South, (Table 3-1) are setup in series where the wastewater first flows through the smaller and older North basin and then through the larger South basin before it is fi nally deep well injected, used as reclaimed water, or sent to the emergency holding pond. Each pilot basin (Table 3-2) was designed to simulate the hydraulic retention time (H RT), flow pattern, and dimension ratios through both the North and South chlorine contact basins. For example, the length to

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33 width ratios seen in the two full-scale basins were averaged and used in the pilot basin design. Full calculations can be found in Appendix A. Table 3-1. Chlorine contact basin dimension ratios. South CCB North CCB Pilot basin L:W 1.2 L:W 1.0 L:W 1.1 L:H 6.3 L:H 5.3 L:H 5.8 W:H 5.2 W:H 5.3 W:H 5.3 C:W 0.1 C:W 0.1 C:W 0.1 No. of channels 8 No. of channels 10 No. of channels 9 L: Length, H: Height, W: Width, C: Channel Width Table 3-2: Pilot chlorine contact basin dimension. Pilot basin dimensions Length (ft) 4.0 Width (ft) 3.7 Height (ft) 0.7 No. channels 9 One basin was equipped with an opaque acry lic cover to block solar radiation from entering and coming in contact with the wast ewater during the disinfection step of the treatment process. The second basin was e quipped with an UV transmitting clear acrylic, or UV-TRANS, cover that will allow solar radiati on, both UV and visible radiation, to come in contact with the wastewater during disinfection. Thus, the basin with the UV radiation transparent cover was termed the TRANS basin and the basin that prevented UV and solar radiation exposure of the wast ewater during the disinfection stage of treatment was termed the OPAQ basin. Each basin had one inlet and one outlet that have inch brass barbs, which allows for the connection of the inch plastic tubing. The Analytical Research Systems Inc. located in Micanopy, Florida constructed the basi ns to specifications presented to them. A fluoroscein tracer analysis was performed on one of the basins to determine the flow

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34 pattern of the pilot basins. It was determin ed that each pilot basin modeled as 41 tanksin-series with a t10 value of 61 minutes. The tracer an alysis was performed with a flow rate of 42 GPH, a HRT of 107 minutes, the full calculations are shown in Appendix B. The feed water for the basins had gone th rough the plant filters but not the chlorine contact basin. The feed wa ter to the pilot basins was first dosed with a known concentration of chlorine (NaOCl), and then split into two equal streams before entering the pilot basins. The chlorine solution prep aration is explained in the Chlorine Dosing section. The chlorine solution was stored in a Nalgene container and added to the pilot process using a Cole-Palmer Variable Speed Economy Driver pump with an Easy Load LC-07518-60 head. A second pump and pump head was available for acid or base addition for some experimental runs, again stor ed in a Nalgene container and added to the pilot process using a Cole-Palmer Variable Speed Economy Driver pump with an Easy Load LC-07518-60 head. Two static mixers we re in place to give adequate mixing. Flowmeters were in place on both basins to en sure steady and equal flow rates. The pilot scale setup schematic and photographs of the system setup are shown in (Figure 3-2 and Figure 3-3), respectively. Wastewater Feed System Materials Tygon tubing o inch ID o inch ID Static mixer, OD 58 inch, ID inch Barbed male pipe NPT connectors: o Thread 18 inch, tube ID 116, clear polypropylene o Thread 14 inch, tube ID 14, natural polypropylene o Thread 14 inch, tube ID 12, natural polypropylene Female tee, pipe size inch, PFA Female reducer, NPT(F) x NPT(F): x 18 inch, PVC Barbed connector, 116 x 116 inch, Clear Polypropylene

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35 Pump Pump Cl2 Acid Static Mixe r Static Mixe r FlowMeter FlowMeter TRANS Basin OPAQ Basin Figure 3-2. Pilot basin system setup.

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36 Figure 3-3. Pilot scale setup; chlorine and acid/base soluti on containers, solution pumps, influent water spigot, static mixers, t-split, TRANS and OPAQ basins. Ten pilot-scale runs were performed at the KWRF. The experimental matrix was as follows: 3 baseline runs o HRT = 2.75 h o Chlorine dose = 7.5-8.0 mg/L Cl2 o pH = no acid/base adjustment 3 low flow runs o 2 low flow runs/average chlorine dose HRT = 3.81 hours Chlorine dose = 9-12 mg/L Cl2 pH=No acid or base adjustment o 1 low flow run/high chlorine dose HRT = 3.81 h Chlorine dose = 16 mg/L Cl2 pH = no acid or base adjustment 1 high chlorine residual o HRT = 2.75 h o Chlorine dose = 8.2 mg/L Cl2 o pH= no acid or base adjustment

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37 1 low chlorine residual o HRT = 2.75 h o Chlorine dose = 6.5 mg/L Cl2 o pH= no acid or base adjustment 1 low pH o HRT = 2.75 h o Chlorine dose = 7 mg/L Cl2 o pH = increased pH (H2SO4 addition) effluent average = 6 1 high pH o HRT = 2.75 h o Chlorine dose = 7 mg/L Cl2 o pH= lowered pH (NaOH addition) effluent average = 9 Chlorine Dosing Clorox bleach (NaOCl) was diluted in order to make the chlorine solutions for the pilot scale study. The standard method Iodometric method I, standard method 4500 Cl B, was used to determine the total chlorine concentration in the concentrated Clorox solution. The concentrated Clorox solution was then diluted with deionized water to provide the desired concentrati on for dosing in the pilot basin experimental runs. Prior to use the chlorine dosing solution concentrati on was measured to determine the actual concentration. The full calculation for all of th e chlorine solutions used to chlorinate the pilot basins can be seen in Appendix C. Pump Test In order to determine the pump rate provi ded by the different settings on the ColePalmer Variable Speed Economy Driver pump with an Easy Load LC-07518-60 head a pump test was performed. The tube used in the system to provide solution dosing was placed in a graduated cylinder filled with ta p water. The beginning volume was recorded, the pump was then set at a numbered position on the pump, the pump was started, and then the volume was recorded after a certain time laps had occurred.

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38 Full Scale In the full-scale study the North basin was used since it was the first basin in the series of the two chlorine c ontact basins and the wastewater had yet to be exposed to UV radiation while containing chlorine. The infl uent wastewater was split at the inlet into two parallel streams. The North basin is 58 ft long and 59 ft wide. A previous study at the KWRF determined that the North and South basins together model as 60 tanks-inseries while the North basin models as 100 tanks-in-series separately.2 One of the parallel streams of the basin, 58 ft by 30 ft area, was covered with three polypropylene tarps to prevent the wastewater from being exposed to UV radiation, the (COV) side. The other side of the basin was left exposed to sunlight radiati on, the (UNCOV) side (Figure 3-4 (a)). The tarps were held down by concrete blocks (Figure 3-4 (b)), while ropes were tide to rings located along the sides of the tarps. The ropes were then tied to concrete blocks located on the ground along the sides of the basin. The concrete blocks holding down the tarps were then removed. There were th ree full-scale experimental runs performed for this study at the KWRF. Figure 3-4. Full-scale setup. (a) Uncovered side of the basin. (b) Covered side of the basin during the full-scale study. The flow rates and chlorine dose for the full-scale study were the consequence of the KWRF operation on the days of the study and were recorded by the operators in the

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39 daily operations log. The daily operations l ogs were used to formulate the discharge monitoring report (DMR) for the Department of Environmental Protection (DEP). Sampling points in the post-aeration basin and North chlorine contact basin for the full-scale study are shown in (Figure 3-5) The sampling points are as follows: 1. Post-aeration basin effluent; wastewater sample directly prior to chlorine injection 2. North chlorine contact basin inlet; where th e wastewater first enters the basin and directly prior to splitting into parallel flows 3. Covered side effluent; directly prior to recombination of parallel flows and the South basin 4. Uncovered side effluent; directly prior to recombination of parallel flows and the South basin Figure 3-5. Sampling points in the post-aera tion basin and North chlorine contact basin for the full-scale study. PostAeration Basin (1) North Chlorine Contact Basin (2) (3) (4)

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40 Calculations Disinfection By-Product Data Normalization To determine if other factors (i.e. UV a nd global radiation) ar e affecting the DBP formation in the pilot and full-scale systems the TTHM and HAA(5) concentrations were normalized to variable parameters (e.g. temp erature) that are known to affect their formation. Among the parameter differences, there was a definite temperature differentiation between the TRANS and OPAQ ba sin in the pilot scale system and also between the COV and UNCOV sides of the North chlorine contact basin in the full-scale system resulting from absorption of radiat ion by the exposed wastewater. Temperature data can be found in the discussion sec tions and also in Appendix E and F. Trihalomethane normalization To compensate for the difference in efflue nt conditions, such as, chlorine residual, temperature, and pH the effluent TTHM con centrations were normalized. Normalization factors for temperature, pH, and free chlo rine residual were used to adjust the concentrations. Since chloroform makes up the majority of the TTHM in every sampling set, the modeling equation for coliform was used in the normalization of the THM concentrations. (Equation 3-1) shows the relationship of chloroform formation to temperature, pH, chlorine residual, and cont act time. The model was taken from a March 1993 American Water Works Association re port on modeling DBP formation during chlorination at potable water treatment plants.13 269 0 874 0 254 404 0 1 561 0 2 018 1 161 1 329 0 3] 01 0 [ ] [ ] [ 064 0 t UV Br Dose Cl T pH TOC CHCl (3-1) ) ( ) ( /3hrs Time t C e Temperatur T L g CHCl L mg Br Cl L mg Dose Cl L mg TOC / / /1 2 2 1 254 cm UV

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41 In the normalization process the OP AQ basin and COV side effluent TTHM concentrations were normalized to T RANS basin and UNCOV side effluent TTHM concentrations, respectively. Normalization factors were calculated from parameter data collected during each sampling run. Th e equation for each parameter normalization factor was developed from Equation 3-1. Equations 3-2, 3-3, and 3-4 are the pH, chlorine residual, and temperature normaliza tion factor equations, respectively, for the normalization of TTHM concentr ation of the OPAQ basin to the TTHM concentration of the TRANS basin. The free ch lorine residual was used in th e normalization process. The equations for the full-scale study were the same except the parameters of the COV and UNCOV sides were used. pH Normalization Factor 161 1 OPAQ TRANSpH pH (3-2) Chlorine Residual Normalization Factor 561 0 OPAQ TRANSCl Cl (3-3) Temperature Normalization Factor 018 1 OPAQ TRANST T (3-4) In order to normalize the OPAQ basin, or COV side of the North basin, the effluent TTHM concentration was multiplied by these normalization factors. The normalized TRANS and OPAQ basin, or UNCOV and COV si des, TTHM concentrations were then compared to determine if other parameters (i.e. solar radiation) had any influence on the TTHM formation.

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42 Haloacetic acid normalization In order to compensate for the differen ce in effluent conditions (i.e., chlorine residual) the effluent HAA concentrations were normalized. Normalization factors for temperature and free chlorine residual were used to adjust the concentrations. Since DCAA makes up the majority of the HAA(5) in the greatest number of sampling sets compared with the other species the m odel equation for DCAA was used in the normalization of the HAA(5) concentrations. Equation 3-5 shows the relationship of DCAA formation to temperature and chlorine residual. The model was taken from a March 1993 American Water Works Associ ation report on DBP formation during chlorination at potable water treatment plants.13 239 0 665 0 568 0 1 480 0 2 726 0 291 0] [ ] 01 0 [ ] [ ] 254 [ ] [ 605 0 t Temp Br Dose Cl UV TOC DCAA (3-5) L mg Br Cl L mg Dose Cl L mg TOC hrs Time t C e Temperatur Temp L g DCAA / / / ) ( ) ( /1 2 2 In the normalization process the OPAQ basin and COV side effluent HAA(5) concentrations were normalized to TRANS basin and UNCOV side effluent HAA(5) concentrations, respectively. Normalization factors were calculated from parameter data collected during each sampling run. Th e equation for each parameter normalization factor was developed from Equation 3-5. Equations 3-6 and 3-7 are the temperature and chlorine residual normaliza tion factor equations, respec tively, for the normalization of HAA(5) concentration of the OPAQ basi n to the HAA(5) concentration of the TRANS

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43 basin. The free chlorine residual was used in the normalization pro cess. The equations for the full-scale study were the same except the parameters of the COV and UNCOV sides were used. Temperature Residual Normalization Factor 665 0 OPAQ TRANSe Temperatur e Temperatur (3-6) Chlorine Residual Normalization Factor 480 0 OPAQ TRANSCl Cl (3-7) In order to normalize the OPAQ basin, or COV side of the North basin, the effluent HAA(5) concentration was multiplied by these normalization factors. The normalized TRANS and OPAQ basin, or UNCOV and COV si des, HAA(5) concentrations were then compared to determine if other parameters (i.e. solar radiation) had any influence on the HAA(5) formation. Average Radiation The average UV and global solar radiation exposure of the wastewater over the HRT of the wastewater in the pilot basin was calculated for each sampling set. Equations 3-8 and 3-9 were used to cal culate the UV and global solar radiation, respectively. Average UV radiation HRT UVHRT t t 0 (3-8) UV= UV radiation readings taken every 5 minutes (mW/cm2) t =minutes of retention time in the pilot basin HRT=hydraulic retention time (min)

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44 Average global solar radiation HRT GSRHRT t t 0 (3-9) GSR=Global solar radiation readi ng taken every 5 minutes (mW/cm2) t =minutes of retention time in the pilot basin HRT=hydraulic retention time (min) Standard Deviation The standard deviation is a measure of how different values are from the average or mean value (Equation 3-10). ) 1 (2 2 n n x x n STD (3-10) STD = Standard Deviation n = number of arguments x = value of argument (n) Paired T-Test The paired t-test was the statistical me thod used to determine if there were statistical differences between sets of collected data from the pilot and full-scale studies. The paired t-test is a variation of the standard t-test and is used to compare two treatment methods where experiments are performed in pa irs and the differences are of interest. Since sample collection was performed in pair s in the pilot and full-scale studies and the differences in the collected data sets are of interest, the paired t-test was appropriate to use. The t*-value used in the paired t-test was calculated using Equation 3-11. n S D tD (3-11) samples of number n deviation Standard S 0 difference Mean D value t tD

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45 The t* values are then compared with the t-value for a given degree of freedom and level of significance. If a t* value is great er than the t-value in the standard Student t table, the difference is said to be signif icant to the degree found in the table. Linear Correlation In order to evaluate the linear correla tion between two difference parameters the one tailed t-test with the Pearson product mo ment correlation coefficient. The Pearson Product momentum, r, varies between and 1 and is unitless. An r-value of and 1 represents a perfect negative and perfect positiv e correlation, respectively. The larger the absolute value of the Pearson product mome ntum the stronger is the degree of linear relationship between the two parameters The Pearson Product momentum was calculated using Equation 3-12. 2 1 2 2 1 2 1) ( ) ( ) )( ( y y x x y y x x ri i n i i i xy (3-12) To determine if the linear correlation was significantly different from zero a significance t-test was performed. First, two test hypothesis were established the first being the null hypothesis, H0, where the correlation is assu med to be zero. The second hypothesis, H1, assumes the other case where the co rrelation is greater than zero. The one tailed t-test was used to determine whic h hypothesis was valid. The t* value used in the correlation determination wa s calculated using Equation 3-13. 21 2 r n r t (3-13)

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46 If the calculated t* value was great er than the t critical value, tc, for a given level of significance for the set degrees of fr eedom than the second hypothesis, H1, was accepted to be true. The degrees of freedom for the linear correlation t-test was n-2. If the t* values was found to be less than the tc the null hypothesis was accepted and the H1 hypothesis was rejected.

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47 CHAPTER 4 DISCUSSION: PILOT-SCALE BASIN As stated previously, the pilot basin w ith the opaque cover that prevented solar radiation exposure of the wastewater was term ed the OPAQ basin. The basin with the transparent cover that allows solar radiati on (UV and global radiat ion) exposure of the wastewater was termed the TRANS basin. Fo r consistency, the comparisons between the TRANS and OPAQ basin in all cases have the OPAQ basin effluent concentration subtracted from the TRANS basin effluent con centration. The paired t-test statistical analysis, along with the Pear son product momentum correlation coefficient, values used in the following pilot-scale study disc ussion can be found in Appendix H. Solar Radiation/Temperature In this study, wastewater that had been treated by the KWRF through filtration was put through one of two parallel pilot chlorine contact basins. The basins were identical except that one pilot basin was covered with a plastic cover that allows UV and global radiation to pass and come in contact with the wastewater (TRANS), while the second basin was covered with a black plastic cove r that was opaque to both the UV and global radiation thus preventing the wastewater from becoming exposed to radiation (OPAQ). The linear correlation between UV and global radiation is shown in Figure 4-1. The Pearson product momentum correlation co efficient for this relationship was 0.996 and the resulting t-test showed a 99% conf idence in a liner correlation between UV and global radiation. Since, the radiation patterns match each other so well, only UV radiation was used in the analysis of chlori ne residual, DBP, and other parameter data.

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48 0 20 40 60 80 100 120 0.001.002.003.004.005.00 Average UV Radiation (mW/cm2)Average Global Horizontals Radiation (mW/cm2) Figure 4-1. Average global horizontal radiat ion versus the average UV radiation over the HRT. Solar radiation increases the temperature of exposed water. The TRANS basin had a translucent cover allowing for the exposur e to UV radiation during the chlorine disinfection resulting in the increase in e ffluent temperature. As the average UV radiation intensity increased during the day, the pilot basin effluent temperature also increased. The effluent temperatures of both the pilot basins are plotted versus the average UV radiation (Figure 4-2). An increase in solar radiation also results in an increase in air temperature as well as the heating of the basins themselves. The wastewater used in OPAQ basin was not expos ed to solar radiati on during the chlorine disinfection process. However, before th e pilot basins, the wastewater went through previous KWRF treatment processes in which it was exposed to solar radiation. So it was expected that the OPAQ basin effluent temp erature would rise due to these conditions.

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49 25.0 27.0 29.0 31.0 33.0 35.0 0.0020.0040.0060.0080.00100.00120.00 Average UV Radiation (mW/cm2)Temperature (C ) TRANS (TEMP) OPAQ (TEMP) Figure 4-2. The effluent temperature of th e TRANS and OPAQ basins plotted versus the average UV radiation exposure of the TRANS basin over the HRT. To determine if the difference in UV radiation exposure of the basins caused the effluent temperatures to differ, statistical pa ired t-tests were performed and the difference in the effluent temperatures of the TRANS and OPAQ basins was plotted versus the average UV radiation the wastewater was exposed to while in the pilot basin (Figure 4-3). The results of the paired t-test showed a 99% confidence level that the basin effluent temperatures were different. Therefore, the opaque cover of the OPAQ basin resulted in a significantly lower effluent temperature. The Pearson product momentum correlation coefficient for the relationship between the effluent temperature differences and the average UV radiation exposure was 0.884 resulting in a 99% confidence in a linear correlation. Thus, the higher effluent temperature of the TRANS basin over the OPAQ basin can be attributed to an increase in the average solar radiation exposure while in the basin. An increase in water temperature enhances the rate of reactions according to the Arrhenius law. Therefore, the increase in water temperature results in an increase of chlorine consumption in a variety of reactions and consequently results in lower chlorine

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50 residual. Also, an increase in temperat ure will increase the formation of DBP, both HAA(5) and TTHM, other variables being held constant. 0.0 1.0 2.0 3.0 4.0 0.001.002.003.004.005.00 Average UV Radiation (mW/cm2) Temperature (C ) Figure 4-3. Difference in effluent temper ature of the basins (TRANS-OPAQ) plotted versus the average UV radiation over the HRT. Chlorine Residual The chlorine residual was monitored during each experimental run of the pilot basins; a constant chlorine dose was set for each pilot run. During the baseline runs the HRT was 2.75 h and the chlorine dosing was kept between 7.5 and 8.0 mg/L Cl2, in order to replicate full scale residual conditions, from between 4 pm the day prior to sampling to 2 pm the day of the sampling. Because it was a pilot study, environmental conditions like solar radiation and influe nt wastewater composition could not be controlled. However, solar radiation, UV and global radiation, as well as pH, temperature, dissolved oxygen, and conductivity were measured during the pilot studies to determine the effect, if any, these fact ors have on chlorine residual and disinfectionby-product (DBP) formation. Because the pilot study used filtered wastewater from the KWRF the composition of the wastewater was not controlled. Depending on the composition of the incoming

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51 wastewater the chlorine demand and the DBP formation potential could change during the course of the experimental run. The filtered wastewater was dosed with chlorine and then split into the two parallel pilot basins. Though the influent wastewater could have fluctuated in chlorine demand and DBP form ation potential, each basin received the same influent wastewater with the same pH and chlorine dose. Since it was a comparison study of the two basin setups on the effect of solar radiation on chlorine residual, disinfection effectiveness, and DBP formation, the fact that the influent wastewater composition was not constant did not affect the outcome of the study. Accordingly, statistical analyses were made with the paired t-test.32 Free Chlorine As previously stated, KWRF uses Cl2 gas addition to disinfect the wastewater prior to discharge, or reuse. The regulatory agencies, EPA and Florida DEP, require the KWRF effluent to have a free chlorine residual of at least 1 mg/L Cl2. Other than the chlorine demand of the wastewater, UV radiation also exerts some chlorine demand in the wastewater, as shown earlier in Equation 1-1. Thus, enough chlorine must be added to meet the chlorine demand of the wastewater, compensate for the UV radiation exposure reduction, as well as maintain a sufficient effluent residual. The effluent free chlorine residual data for the (TRANS-OPAQ) pilot basins was partitioned into range increments for comparison (Figure 4-4). Most samples were in the >2.0 mg/L Cl2 residual range increment for both the TRANS and OPAQ basins. However, the OPAQ basin had a greater number of samples, 11, than the TRANS basin, 8, at the >2 mg/Cl2 residual increment. The higher chlorine residual ensures a greater chemical disinfection potential.

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52 0 2 4 6 8 10 12 <0.50.5-1.0 1.0-1.5 1.5-2.0>2.0 Free Chlorine (mg/L Cl2)# of Instances TRANS Free Cl2 OPAQ Free Cl2 Figure 4-4. Free chlorine residual sampling sets in particular residual ranges for the TRANS and OPAQ basins. The only difference between the two basins was the exposure to UV radiation, in order to determine if this was the cause of the chlorine residual differences and to ascertain if the differences between the tw o basins was statistically different, the difference in the free chlorine residual of the (TRANS-OPAQ) basins for each experimental run was plotted versus the average UV radiation the wastewater was exposed to over the respective HRT (Figure 4-5) The majority of the points of the plot were negative and were in the fourth quadran t, showing that the OPAQ basin effluent had a higher chlorine residual than the TRANS basi n in almost all of the sampling runs. Only in three sampling times was the TRANS basin effluent free chlorine residual higher than the OPAQ effluent. The largest fr ee chlorine difference between th e two basins was -2.40 mg/L Cl2 (TRANS-OPAQ) at an average UV radiation exposure of 3.77 mW/cm2. The average difference of free chlorine resi dual between the TRANS and OPAQ basins

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53 for the 30 pilot study sampling sets was .44 mg/L Cl2. According to the paired t-test analysis, there was 99% confidence that the fr ee chlorine concentrations of the TRANS and OPAQ basins were statistically di fferent. The Pearson product momentum correlation coefficient for the difference in effluent free chlorine residuals and the average UV radiation was -0.405 signifying a 95% confidence that there was a negative linear correlation. Thus, as the average UV radiation increased the difference in the effluent free chlorine residuals of the basins increased. -3.00 -2.50 -2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 0.001.002.003.004.005.00 Average UV Radiation (mW/cm2)Free Chlorine Residual (mg/L Cl2) Figure 4-5. Free chlorine residual d ifference of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus averag e UV Radiation over the HRT of the wastewater in the basin for all pilot studies. A plot of only the baseline runs is shown in Figure 4-6. As in the plot of all experimental runs, Figure 4-6 shows the OPAQ basin, the basin that was not exposed to UV Radiation, had a greater free chlorine resi dual in all of the runs, except in one sampling instance. According to the paire d t-test method there was a 99% confidence level that the TRANS and OPAQ basin efflue nt free chlorine resi duals were different

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54 during the baseline experiments. Using the paired t-test method the Pearson product momentum correlation coefficient was -0.574 resulting in a 99% confidence that there was a linear correlation between the difference in effluent free chlorine concentration and UV radiation exposure of the wastewat er for the baseline experiments. -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 0.001.002.003.004.005.00 Average UV Radiation (mW/cm2)Free Chlorine Residual (mg/L Cl2) Figure 4-6. Free chlorine residual d ifference of the OPAQ and TRANS basins (TRANS-OPAQ) plotted versus averag e UV radiation over the HRT of the wastewater in the basin for baseline parameters. Since UV radiation catalyzes the reduction of HOCl, it was to be expected that the TRANS (UV and global radiation translucent pl astic covered) basin would have a lower effluent free chlorine residual than the OPAQ basin. The plots in Figures 4-5 and 4-6 support this expectation during the pilot study. It is also commonly accepted, given that the chlorine dosing is constant, that as the water or wastewater temperature increases, th e amount of chlorine residual will decrease. The difference in the free chlorine residua l of the TRANS and OPAQ basins is shown versus the difference in temperature between the basins (Figure 4-7). All except two

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55 points were in the fourth qua drant, showing that TRANS had higher temperatures but lower effluent free chlorine residuals than the OPAQ basin. Using the paired t-test method the Pearson product momentum correla tion coefficient was 0.334 resulting in a 95% confidence that there was a linear correla tion between the difference in effluent free chlorine concentration and the difference in temperature. -3.00 -2.00 -1.00 0.00 1.00 2.00 0.01.02.03.04.0 Temperature (C)Free Chlorine Residual (mg/L Cl2) Figure 4-7. Free chlorine difference of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus the difference in temp erature for all of the pilot studies. A plot of only the baseline runs is shown in Figure 4-8. As in the plot of all experimental runs, the TRANS basin had higher effluent temperatures and lower effluent free chlorine residual. The higher temperature causes a faster rate of chlorine reduction, so the cause for greater chlorine loss in the T RANS basin was, in part, the result of this phenomenon. According to the paired t-test the Pearson product momentum correlation coefficient was 0.319 but did not result in a significant linear co rrelation between the

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56 difference in effluent free chlorine concentra tion and the difference in temperature for the baseline experiments. -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 0.001.002.003.004.00 Temperature (C)Free Chlorine Residual (mg/L Cl2) Figure 4-8. Free chlorine difference of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus the difference in te mperature for baseline parameters. As expected, the TRANS, or UV and globa l radiation translucent plastic covered basin had higher effluent temperatures than the OPAQ, or opaque covered, basin this would contribute to the difference in chlori ne residual. The one instance where the TRANS basin free chlorine residual was higher than the OPAQ basin occurred on 7/14/2004 at 9 am. Prior to this time, duri ng the HRTs for the samples taken at 9 am on that day, a significant flow meter fluctuation was noticed and was adjusted for subsequent sampling times on that day. The pilot basin system was setup to simu late the hydraulic retention time (HRT), flow pattern, and dimension ratios of the No rth and South chlorine contact basins that were setup in series at the KWRF. However, the pilot system scale was much smaller than that of the full-scale and thus the volume of water contained in the basins were less than that of the full-scale. Thus, solar radi ation had a greater effect on the pilot basin

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57 temperature differences than the full-scale basin temperature differences. The average temperature difference between the TRANS a nd OPAQ basins during the pilot study was 1.5 C while the average difference in te mperature between the UNCOV and COV in the full-scale sides was 0.3C. Total Chlorine As stated previously, the total chlorine re sidual is a measure of the free and any combined chlorine present. Since the KWRF us es biological processe s, nitrification and denitrification, to remove ammonia nitrogen pr esent in the wastewater, it is unlikely that chloramines would form. The KWRF operators add enough chlorine to pass the breakpoint where free chlorine residual is form ed. Thus, the difference in total and free chlorine is what is termed irreducible chlorine residual1; though there are no inorganic chloramines present, there is a difference in the total and free chlorine residuals. The irreducible residual could be due, in part, to the presence of dichloramine and trichloramine. Since total chlorine residual consists mo stly of free chlorine, the results and relationships between the to tal chlorine residu al and other parameters should be comparable to those of the free chlorine residual. The environmental conditions that result in a lowering of the free chlorine resi dual would also result in a decrease in the total chlorine residual. The effluent total chlorine re sidual data for the TRANS and OPAQ pilot basins was partitioned into range increments for comparison (Figure 4-9). The most samples were in the > 2.0 mg/L Cl2 residual range increment for both the TRANS and OPAQ basins. However, the OPAQ basin had a greater number of samples, 22, than the TRANS basin, 15, at the >2 mg/Cl2 residual increment. As stated before, since the total chlorine residual

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58 was composed mostly of free chlorine the re sults were similar to those shown for free chlorine residual. 0 5 10 15 20 25 <0.50.5-1.0 1.0-1.5 1.5-2.0>2.0 Total Chlorine (mg/L Cl2)# of Instances TRANS Total Cl2 OPAQ Total Cl2 Figure 4-9. Total chlorine residual sampling sets in particular residual ranges for the TRANS and OPAQ basins. The difference in the total chlorine re sidual of the (TRANS-OPAQ) basins is shown versus the average UV radiation the wastewater was exposed to over the HRT (Figure 4-10). The majority of the points we re negative and were in the fourth quadrant, showing that the OPAQ basin had higher effluent total chlorine residual than the TRANS basin in nearly all of the sampling runs. Only in four sampling sets was the TRANS basin effluent total chlorine residual higher than the OPAQ effluent. The largest total chlorine difference between the two basins was -2.50 mg/L Cl2 (TRANS-OPAQ) at an average UV Radiation exposure of 2.55 mW/cm2. The average difference of total chlorine residual between the TRANS and OP AQ basins for the 30 pilot-scale sampling sets was -0.50 mg/L Cl2 with a standard devi ation of 0.67 mg/L Cl2. According to the paired t-test method there was a 99% confid ence level that the TRANS and OPAQ basin

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59 effluent total chlorine residuals were different. Also, using the paired t-test method the Pearson product momentum correlation coeffi cient was -0.281 and did not result in a significant linear correlation between the difference in effluent total chlorine concentration and UV radiation exposure of the wastewater. Thus, the total chlorine difference was not significantly affected by th e increases in the average UV radiation, although the irradiated basin had significantly le ss total chlorine residual than the covered basin. -3.00 -2.50 -2.00 -1.50 -1.00 -0.50 0.00 0.5011.00 0.001.002.003.004.005.00 Avg UV Radiation (mW/cm2)Total Chlorine Residual (mg/L Cl2) Figure 4-10. Total chlorine residual di fference of the OPAQ and TRANS basins (TRANS-OPAQ) plotted versus aver age UV Radiation over the HDT of the wastewater in the basin for all pilot studies. The difference in the total chlorine re sidual of the (TRANS-OPAQ) basins is shown versus the difference in temperature be tween the basins (Figure 4-11). All except two points were negative and were in the f ourth quadrant, showing that TRANS had a higher temperature but lower total chlorine re sidual than the OPAQ basin. Using the paired t-test method the Pearson product mo mentum correlation coefficient was -0.227 and did not result in a significant linear corr elation between the difference in effluent total chlorine concentration and difference in temperature.

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60 -3.00 -2.00 -1.00 0.00 1.00 0.01.02.03.04.0 Temperature (C)Total Chlorine Residual (mg/L Cl2) Figure 4-11. Total chlorine residual di fference of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus the diffe rence in temperature between the basins. The basin with the higher effluent temper ature also had significantly lower free and total chlorine residual. Though, there was a 99% confidence level that the total chorine residual was different between the two basi ns there was no significant correlation between that difference and the exposure to UV radiation or difference in temperature. Though it is important to note that solar radi ation exposure of the wastewater does result in an increase in water temperature, it is di fficult to separate the effect of temperature increase and UV radiation on the difference in chlorine residual in the TRANS and OPAQ pilot basins. Disinfection By-Products The chlorination of KWRF wastewater ensu res the safety of reuse water users and prevents coliform and other bacterial contamin ation from entering the Floridan aquifer, a drinking water source. Besides the consum ption of chlorine through the disinfection process, the reaction of chlo rine with humic substances, ex tracellular alga l products, and other DBP precursors not only reduces the chlorine residual but also induces the

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61 formation of DBP. Because of the known carc inogenic health effect s attributed to the presence of DBP in drinking water, the EPA had placed an 80 g/L limit on TTHM concentration and a 60 g/L limit on HAA(5) concentration. Although there are other known disinfection by-products only trihalomethanes and haloacetic acids are regulated by the EPA in the drinking water regulations and thus were the only DBP measured in this study. Several factors affect the extent of DBP formation, such as, chlorine dose, temperature, pH, and contact time. It is commonly known that as the chlorine dosing is increased during chlorinati on the amount of DBP that forms also increases.6 An increase in temperature will also result in an increase in DBP formation.6 Trihalomethane The TTHM concentration of effluent samp les was analytically determined using GC/MS instrumentation. The TTHM concentrati on in this study refers to a composite of four molecules (chloroform, bromodichloromethane, dibromochloromethane, and bromoform). In order to compare TTHM formation on a collective basis the mass concentrations should be converted to a co mmon unit and then summed. Molarity was used as the common unit for this study as it is widely used. The THM speciation for each of the sampling runs can be seen in Appendix E. The TTHM effluent mass concentrations we re separated into range increments and plotted in a histogram (Figure 4-12). The conc entrations are raw values in that they were not normalized to pH, temperature, nor chlorine dose. The OPAQ basin had the same number of samples, nine, in each range up to 150 g/L and then only three samples in the >200 g/L range. Most of the effluent TTH M concentrations fell within the 50-100 g/L

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62 range for the TRANS basin, one sample in the 150-200 g/L range, and three samples >200 g/L range. The TTHM effluent molar c oncentrations were separated into range increments and plotted in a histogram (Fi gure 4-13). Most of the effluent TTHM concentrations fell within the 0.5-1.0 mole/ L range for the TRANS basin and in the less than 0.5 mole/L for the OPAQ basin. 0 2 4 6 8 10 12 14 <5050-100 100-150 150-200>200 TTHM ( g/L)# of Instances TRANS TTHM OPAQ TTHM Figure 4-12. The TTHM effluent mass con centrations for the TRANS and OPAQ basins are shown in range increments. 0 3 6 9 12 15 18 <0.50.5-1.01.0-1.51.5-2.0>2.0 TTHM ( moles/L)# of Instances TRANS TTHM OPAQ TTHM Figure 4-13. The TTHM effluent molar conc entrations for the TRANS and OPAQ basins are shown in range increments.

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63 Previously, it was shown that the OPAQ basin, the basin with the cover that prevented the wastewater from being exposed to UV radiation, had higher effluent free chlorine residual than the TRANS basin fo r the majority of the pilot runs. Common theory would then lead to the conclusion that the OPAQ basin, with a higher chlorine residual, would result in a hi gher THM formation as well. The difference in the TRANS and OPAQ TTHM mass and molar effluent c oncentrations for all of the pilot basin experimental runs is shown as a histogram (Figures 4-14 and 4-15), respectively. The differences in TTHM concentrations were the actual concentrations in the effluent sample; the concentrations were not normalized for the differences in chlorine residual, temperature or pH. There were 10 sampling sets of a total of 30 experimental sampling sets where the OPAQ basin had a higher TTHM concentration than the TRANS basin. Of the 10 sampling sets where the OP AQ basin had a higher TTHM effluent concentration than the TRANS basin, 9 coin cided with the OPAQ basin effluent having a higher free chlorine residual that the TRANS ba sin. Also, of the sampling sets where the OPAQ basin effluent had a higher TTHM con centration than the TRANS basin, 3 were on the July 28, 2004 and 3 were on August 2, 2004. Both of those days were nonbaseline experimental pilot runs. On July 28th sodium hydroxide (NaOH) was added to increase the influent pH to the basins. On August 2nd the flow rate was reduced from the baseline flow rate of 28 GPH (HRT of 2 h and 45 min) to 20 GPH (HRT of 3 h and 50 min). In the rest of the 30 sampling sets the TRANS basin mass effluent concentration was higher than that of the OPAQ basin. The average difference of effluent TTHM mass concentration between the TRANS and OPAQ basins for the 30 pilot-scale sampling sets was 6.9 g/L with a standard deviation of 29.1 g/L. The average difference of effluent

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64 TTHM molar concentration betw een the TRANS and OPAQ basins for the 30 pilot-scale sampling sets was 0.05 mole/L with a standard deviation of 0.22 moles/L. According to the paired t-test there was no significa nt difference between the TTHM effluent concentration of the TRANS and OPAQ basi ns, mass or molar despite the typically higher chlorine residual in the OPAQ basin. 0 2 4 6 8 10 12 <=00-88-1616-24>24 TTHM ( g/L)# of Instances Figure 4-14. Difference in TTHM concentr ation between the TRANS and OPAQ sides (TRANS-OPAQ) separated into mass concentration ranges. 0 5 10 15 20 <=00-0.250.25-0.500.50-0.75>0.75 TTHM ( moles/L)# of Instances Figure 4-15. Difference in TTHM concentr ation between the TRANS and OPAQ sides (TRANS-OPAQ) separated into molar concentration ranges.

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65 The difference in TTHM effluent concentrat ion is plotted versus the difference in free chlorine residual for mass and molar concentrations (Figures 4-16 and 4-17), respectively. Using the paired t-test method, with the Pearson product momentum correlation coefficient, neither the mass nor the molar TTHM concentration difference correlates to a significant degree with the difference in free chlorine residual. -100 -50 0 50 100 150 -3.00-2.00-1.000.001.002.00 Free Chlorine (mg/L Cl2) TTHM ( g/L) Figure 4-16. Difference in TTHM effluent mass concentration of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus the difference in free chlorine residual of the TRANS and OPAQ basins. -1.00 -0.50 0.00 0.50 1.00 -3.00-2.00-1.000.001.002.00 Free Chlorine (mg/L) TTHM ( moles/L ) Figure 4-17. Difference in TTHM effluent molar concentration of the TRANS and OPAQ basins (TRANS-OPAQ) plotte d versus the difference in free chlorine residual of the TRANS and OPAQ basins.

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66 The difference in the TRANS and OPAQ TT HM mass effluent concentrations for baseline pilot basin experiment al runs is plotted versus th e difference in free chlorine residual (Figure 4-18). In only one sample during the baseline runs was the OPAQ basin TTHM effluent concentration higher than that of the TRANS basin. This one sample out of nine sampling sets coincided with a highe r free chlorine residual in the OPAQ basin than the TRANS basin. Using the paired t-test the difference in TTHM effluent concentration does not correlate to a signi ficant degree with the difference in free chlorine residual in the baseline experiments. -50 -25 0 25 50 75 100 125 -1.50-1.00-0.500.000.501.001.50 Free Chlorine Residual (mg/LCl2)TTHM ( g/L) Figure 4-18. Difference in TTHM mass efflue nt concentration between the TRANS and OPAQ basins (TRANS-OPAQ) plotte d versus the difference in free chlorine residual between the TRANS and OPAQ basins for baseline runs. As stated previously, trihalomethane formation is affected by environmental conditions, such as, temperature, pH, and free chlorine residual. The pH, temperature, and free chlorine residual differences of the basins need to be addressed to allow an accurate comparison of the trihalomethane form ation in the two basins. In order to compensate for the differences between these parameters in the basins effluents the

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67 TTHM concentrations were normalized. The manner in which the TTHM concentrations were normalized is explained in the methods section. Each of the basin effluents, TRANS and OPAQ, were sampled and trihalomethane concentrations were measured during every sampling event and time. The TTHM formation for all of the samp ling runs for both the TRANS and OPAQ basins was, for the most part, as chloroform Chloroform made up at least 70%, by mass, of the TTHM formed for both basins during each of the sampling runs of the chlorination pilot study (Figure 4-19). 74% 22% 4% 0% Chloroform Bromodichloromethane Dibromochloromethane Bromoform Figure 4-19. Speciation of the THM formati on in the TRANS effluent on a mass basis sampled at 9 am on August 23, 2004. Because chloroform makes up 70% or higher, by mass, of the TTHM formed in the pilot basins the THM model for chloroform fo rmation was used in the normalization of the OPAQ basin effluent TTHM concentrat ion to that of the TRANS basin. The average, minimum, and maximum values of the normalization factors used to normalize the OPAQ effluent TTHM concentrations to the TRANS effluent TTHM concentrations are shown in (Table 4-1). All TTHM normalized data can be found in

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68 Appendix D. The average values of these normalization factors give an idea of how much the difference in the parameter affects the TTHM concentration of the two basins. The farther the normalization factor is from 1 the greater the parameter contributes to the TTHM concentration difference between the basins. The free chlorine residual normalization factor deviates the most from 1, with a value of 0.85, and thus is the determining factor in the difference of the TTHM concentration between the two basins. The chlorine residual having the greatest eff ect on the TTHM concentration difference of the two basins is important in that in almost all of the cases the OPAQ basin had a higher free chlorine residual effluent than the TRANS basin, however, the OPAQ basin in almost all cases had a lower TTHM effluent concentration. Table 4-1. Normalization factors us ed to normalize OPAQ TTHM effluent concentrations to TRANS TTHM effluent concentrations. pH normalization factor Temperature normalization factor Chlorine residual normalization factor OPAQ OPAQ OPAQ Average 1.00 1.05 0.85 Maximum 1.06 1.13 1.44 Minimum 0.92 1.00 0.46 The TTHM mass concentration comparison was a good way to examine how the two basin systems compare with EPA DBP dr inking water standards. The effluent normalized total trihalomethane (TTHM) mass and molar concentrations were separated into range increments and plotted in a hist ogram (Figure 4-20 and 4-21), respectively. The TRANS basin effluent TTHM concentrations fell mostly in the 50-100 g/L range while the OPAQ basin TTHM effluent concentrat ions fell mostly in the less than 50 g/L range. Similarly, the TRANS basin TTHM molar concentrations fell mostly in a concentration range increment higher than the those of the OPAQ basin, 0.5-1.0 and <0.5

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69 mole/L respectively. The results show th e TRANS basin tending to produce effluent TTHM concentrations in a higher range th an the OPAQ basin over several operating conditions, described in Chap ter 3 Materials and Methods. 0 2 4 6 8 10 12 14 <5050-100 100-150 150-200>200 TTHM' ( g/L)# of Instances TRANS TTHM' OPAQ TTHM' Figure 4-20. Normalized TTHM effluent mass concentrations for the TRANS and OPAQ basins are shown in range increments. 0 2 4 6 8 10 12 14 16 <0.50.5-1.0 1.0-1.5 1.5-2.0>2.0 TTHM' ( moles/L)# of Instances TRANS TTHM' OPAQ TTHM' Figure 4-21. Normalized TTHM effluent molar concentrations for the TRANS and OPAQ basins are shown in range increments.

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70 The difference in the normalized TTHM concentration (TTHM) was separated into mass concentration ranges (Figure 4-22) In only seven sampling sets was the OPAQ basin TTHM concentration higher than the TRANS basin effluent concentration. Most sampling sets of the TTHM mass concentration difference were in the >24 g/L range, with 10 sampling sets. There were th en five sampling sets where the difference between the TRANS and OPAQ basin were in the 0 to 8 g/L and five sampling sets in the 8 to 16 g/L ranges. Using the paired t-test method there was a 99% confidence level that there was a difference between the TRANS basin TTHM concentration and the OPAQ basin TTHM concentration. 0 2 4 6 8 10 <00-8 8-16 16-24>24 TTHM' ( g/L)# of Instances Figure 4-22. Difference in TTHM concentr ation between the TRANS and OPAQ sides (TRANS-OPAQ) separated into mass concentration ranges. The difference in the normalized TTHM concentration was separated into molar concentration ranges (Figure 4-23). Again, the histogram shows that in only seven sampling sets did the OPAQ basin have a higher TTHM concentration than the TRANS basin. Most sampling sets of the TTHM molar concentration difference were in the 0 to

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71 0.25 moles/L range. There were then two sampling sets where the difference between the TRANS and OPAQ basin were in the 0.25 to 0.50 moles/L and two sampling sets in the 0.50 to 0.75 moles/L ranges. Using the paired t-test method there was a 99% confidence level that there was a difference between the TRANS basin TTHM concentration and the OPAQ basin TTHM c oncentration. Thus, the TRANS basin TTHM concentrations were significantly higher than the OPAQ basin TTHM concentrations. 0 2 4 6 8 10 12 14 16 18 20 <00-0.25 0.25-0.50 0.50-0.75>0.75 TTHM' ( moles/L)# of Instances Figure 4-23. Difference in TTHM concentration between the TRANS and OPAQ sides (TRANS-OPAQ) separated into molar concentration ranges. The difference in the normalized TTHM mass concentrations were plotted versus the average UV radiation exposure of the TR ANS basin over the HRT (Figure 4-24). The majority of the points, all but 7, were in the first quadrant meaning that the OPAQ basin had a lower normalized TTHM effluent concentration than the TRANS basin in almost all of the sampling periods. The average difference of the normalized effluent TTHM concentration between the TRANS a nd OPAQ basins for the 30 pilot-scale

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72 sampling sets was 17.1 g/L with a standard deviation of 31.6 g/L. Using the paired ttest the normalized difference in TTHM efflue nt concentration does not correlate to a significant degree with the av erage UV radiation exposure. -80.0 -60.0 -40.0 -20.0 0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 0.001.002.003.004.005.00 Average UV Radiation (mW/cm2) TTHM' ( g/L) Figure 4-24. Difference in normalized TTHM mass concentration of the TRANS and the OPAQ basins (TRANS-OPAQ) plotted versus the average UV radiation. exposure over the HRT. The difference in the normalized TTHM mola r concentrations was plotted versus the average UV radiation the TRANS basin was exposed to over the HRT (Figure 4-25). The majority of the points, all but 7, were in the first quadrant meaning that the OPAQ basin had a lower TTHM effluent concentrati on than the TRANS basin in almost all of the sampling periods. The average difference of the normalized effluent TTHM molar concentration between the TRANS and OPAQ basins for the 30 pilot-scale sampling sets was 0.13 moles/L with a standard deviation of 0.24 moles/L. Using the paired t-test the normalized difference in TTHM effluent concentration does not correlate to a significant degree with the av erage UV radiation exposure.

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73 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60 0.80 1.00 0.001.002.003.004.005.00 Average UV Radiation (mW/cm2) TTHM' ( moles/L) Figure 4-25. Difference in normalized TTH M molar concentration of the TRANS and the OPAQ basins (TRANS-OPAQ) plotted versus the average UV radiation exposure over the HRT. The fact that in all but seven sampli ng sets the OPAQ basin had a lower TTHM concentration than the TRANS basins was contrary to the common theory that a higher residual will result in a higher TTHM concentration. The TTHM and chlorine data analysis suggest that the chlorine disinfec tion process tends to produce less TTHMs if UV radiation and solar radiation exposure of the wastewater was prevented. The data also validate the common concept that UV radiation catalyzes the reduction of free chlorine (HOCl). The data analyses suggest that the OPAQ basin, with the opaque cover that prevents wastewater exposure to UV radiation during the chlorination disinfection process, for the majority of sampling sets, had a lower formation of THM than the TRANS basin. This phenomenon contrasts with the more common theory that a higher chlorine residual will result in a greater formation of THM. The difference between the basins was the exposure of the wastewater to UV radiation du ring the chlorination disinfection process. The data and statis tical analysis suggest that preventing UV

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74 radiation and solar radiation exposure of wastewater during the chlorine disinfection stage at the KWRF had two benefits: 1. The prevention of chlorine loss to the free chlorine reduction reaction by removing the UV radiation as the catalyst 2. A lower THM concentration than with the conventional method of allowing UV radiation to come in contact with wastew ater during the chlorine disinfection stage in the KWRF treatment process. Haloacetic Acid The HAA(5) concentration of an effluent sample is the summed values of the monochloroacetic acid (MCAA), monobromo acetic acid (MBAA), dichloroacetic acid (DCAA), dibromoacetic acid (DBAA), and trichloroacetic acid (TCAA) concentrations calculated for the said sample using the GC/E CD. The HAA(5) speciation for each of the sampling runs can be seen in Appendix E. In order to compare HAA(5) formation on a collective basis the mass concen trations should be converted to a common unit and then summed. The HAA(5) wastewater effluent samples taken from the OPAQ basin on June 23, at 9am, and the TRANS basin on July 14, at 2 pm, and July 26, at 9 am, were damaged prior to analysis and were not used in the pilot-study discussion. The HAA(5) effluent mass concentrations were separated into range increments and plotted in a histogram (Figure 4-26). The concentrations are raw values in that they were not normalized to temperature or chlori ne residual. Most of the effluent HAA(5) concentrations fell within the less than 50 g/L range for the TRANS basin and the OPAQ basin, with 11 and 17 samples resp ectively. The HAA(5) effluent molar concentrations were separated into range increments and plotted in a histogram (Figure 4-27). Most of the effluent HAA(5) concentrations fell within the less than 0.5 mole/L range for the TRANS basin and the OPAQ basin, with 24 and 25 samples,

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75 respectively. It is good to note that the majority of the TRANS and OPAQ basin HAA(5) effluent concentrations fall in the range that is below the proposed EPA standard. 0 2 4 6 8 10 12 14 16 18 <5050-100 100-150 150-200>200 HAA ( g/L)# of Instance s TRANS HAA OPAQ HAA Figure 4-26. The HAA(5) effluent mass concentrations for the TRANS and OPAQ basins are shown in range increments. 0 4 8 12 16 20 24 28 <0.50.5-1.01.0-1.51.5-2.0>2.0 HAA ( moles/L)# of Instances TRANS HAA OPAQ HAA Figure 4-27. The HAA(5) effluent mola r concentrations for the TRANS and OPAQ basins are shown in range increments. The difference in the HAA(5) concentrations (HAA(5)) were separated into mass and molar concentration ranges in (Figure 428 and 4-29), respectively. In eighteen of the twenty-seven sampling sets the TRANS basin HAA(5) mass concentration was higher than the OPAQ basin effluent concentration and in sixteen of the twenty-seven sampling sets the TRANS basin molar concentration was greater than the OPAQ basin

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76 concentration. In the HAA(5) mass concentration difference histogram the most sampling sets were in the <=0 g/L range due to the concentrations being distributed amongst the higher ranges. The average difference in HAA(5) effluent mass concentration was 7.22 g/L with a standard deviation of 32 g/L. Most sampling sets in the HAA(5) molar concentration difference histogram were in the 0-0.25 mole/L range, with thirteen sampling sets. The aver age difference in HAA(5) effluent molar concentration was 0.02 mole/L with a standard deviation of 0.26 moles/L. Using the paired t-test method it was determined that there was no significant difference between the TRANS and OPAQ effluent HAA(5) concentrations. 0 2 4 6 8 10 <=00-88-1616-24>24HAA (g/L)# of Instances Figure 4-28. Difference in HAA(5) concentr ation between the TRANS and OPAQ sides (TRANS-OPAQ) separated into mass concentration ranges. 0 5 10 15 <=00-0.250.25-0.500.50-0.75>0.75 HAA ( moles/L)# of Instances Figure 4-29. Difference in HAA(5) concentr ation between the TRANS and OPAQ sides (TRANS-OPAQ) separated into molar concentration ranges.

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77 The difference in HAA(5) effluent ma ss concentrations of the TRANS and OPAQ basins was plotted versus the difference in free chlorine residual of the TRANS and OPAQ basins (Figure 4-30). As stated prev iously, in eighteen of the twenty-seven sampling sets the TRANS basin HAA(5) effl uent mass concentrations were higher than those of the OPAQ basin. Using the paire d t-test method, with the Pearson product momentum correlation coefficient, it was de termined that there was no significant correlation between the difference in HAA(5) mass concentration and the difference in free chlorine residual. -100 -75 -50 -25 0 25 50 75 100 -3.00-2.00-1.000.001.002.00 Free Chlorine Residual (mg/L Cl2)HAA ( g/L) Figure 4-30. Difference in HAA(5) mass concentration of the TRANS and the OPAQ basins (TRANS-OPAQ) plotted versus the difference in free chlorine residual of the TRANS and OP AQ basins (TRANS-OPAQ). The difference in HAA(5) effluent molar concentrations of the TRANS and OPAQ basins was plotted versus the differen ce in free chlorine residual of the TRANS and OPAQ basins in (Figure 4-31). In sixt een of the twenty-seven sampling sets the TRANS basin HAA(5) effluent concentrations were higher than those of the OPAQ

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78 basin. Using the paired t-test method, w ith the Pearson product momentum correlation coefficient, it was determined that there was no significant correlation between the difference in HAA(5) molar concentration and the difference in free chlorine residual. -0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60 0.80 -3.00-2.00-1.000.001.002.00 Free Chlorine Resdual (mg/L Cl2)HAA ( moles/L) Figure 4-31. Difference in HAA(5) molar concentration of the TRANS and the OPAQ basins (TRANS-OPAQ) plotted versus the difference in free chlorine residual of the TRANS and OPAQ basins (TRANS-OPAQ). Neither the HAA(5) concentration or the TTHM concentration effluent differences correlate with the difference in effluent free chlorine residual. In the HAA(5) analysis in all but three of the thirty sampling sets the DCAA made up the highest percentage of the HAA(5)s. Thus, the HAA(5) OPAQ basin effluent HAA(5) concentrations were normalized to the HAA(5) TRANS basin effluent using the temperature and free chlorine concentration DCAA normalization factors. The speciation of HAA(5) in the OPAQ basin effluent duri ng a baseline run on August 30, 2004 taken at 12 pm is shown with species percentage (F igure 4-32). In this case, DCAA made up 58% of the HAA(5) mass concentration.

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79 0% 0% 58% 0% 42% MCAA MBAA DCAA DBAA TCAA Figure 4-32. Speciation of the HAA(5) form ation in the OPAQ effluent on a mass basis sampled at 12 pm on August 30, 2004. Like THM formation, HAA(5) formation is affected by environmental conditions, such as, temperature and free chlorine residual. In order to compensate for the differences between these parameters in the basins effluents the HAA(5) concentrations were normalized. All HAA(5) normalized data can be found in Appendix D. Normalized HAA(5) concentrations, mass and molar, are denoted as HAA(5). Though DCAA did not make up the highest percentage in all sampling sets it did make up the highest percentage of the HAA(5) concentratio ns in the most numerous sampling sets. The average, minimum, and maximum values of the normalization factors used to normalize the OPAQ effluent HAA(5) concen trations to the TRANS effluent HAA(5) concentrations is shown (Table 4-2). The av erage values give an idea of how much the difference in the parameter affects the HAA(5) concentration of the two basins. The farther the normalization factor is from 1 the greater the parameter contributes to the HAA(5) concentration difference between the basins. The fr ee chlorine residual normalization factor deviates the most from 1, with an average value of 0.86, and thus is

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80 the determining factor in the difference of the HAA(5) concentration between the two basins according to the model. The chlori ne residual having the gr eatest effect on the HAA(5) concentration difference of the two basins is important in that in almost all of the cases the OPAQ basin had a higher free chlorine residual effluent than the TRANS basin, however, the OPAQ basin in eighteen of the twenty-seven sampling sets had a lower normalized HAA(5) mass effluent concentration. Table 4-2. Normalization factors us ed to normalize OPAQ HAA(5) effluent concentrations to TRANS HAA(5) effluent concentrations. Temp (C) Normalization Factor Chlorine Residual Normalization Factor OPAQ OPAQ Average1.03 0.86 Maximum1.08 1.36 Minimum1.00 0.51 The HAA(5) effluent mass concentrations were separated into range increments and plotted in a histogram (Figure 4-33). Si milar to the raw HAA(5) histogram, most of the effluent HAA(5) concentrations fell w ithin the less than 50 g/L range for the TRANS basin and the OPAQ basin, with eleven and sixteen samples respectively. The HAA(5) effluent molar concentrations were se parated into range increments and plotted in a histogram (Figure 4-34). Similar to th e raw HAA(5) histogram, most of the effluent HAA(5) molar concentrations fe ll within the less than 0.5 mole/L range for the TRANS basin and the OPAQ basin, with twenty-five and twenty-six samples, respectively. Similar to the raw HAA(5) concentrations, th e majority of the TRANS and OPAQ basin HAA(5) effluent concentrations fall in th e range that is below the proposed EPA standard.

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81 0 4 8 12 16 20 <5050-100 100-150 150-200>200 HAA' ( g/L)# of Instances TRANS HAA' OPAQ HAA' Figure 4-33. The HAA(5) effluent mass concentrations for the TRANS and OPAQ basins are shown in range increments. 0 5 10 15 20 25 30 <0.50.5-1.01.0-1.51.5-2.0>2.0 HAA' ( moles/L)# of Instances TRANS HAA' OPAQ HAA' Figure 4-34. The HAA(5) effluent molar concentrations for the TRANS and OPAQ basins are shown in range increments. The difference in the HAA(5) concentrations (HAA(5)) were separated into mass and molar concentration ranges in (Figure 4-35 and 4-36), respectively. In eighteen

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82 of the twenty-seven sampling sets the TRANS basin HAA(5) mass concentration was higher than the OPAQ basin effluent concentrat ion and in nineteen of the thirty sampling sets the TRANS basin molar concentra tion was greater than the OPAQ basin concentration. In the HAA(5) mass concen tration difference histogram the same number of sampling sets were in the <=0 g/L range The average differen ce in HAA(5) effluent mass concentration was 9.05 g/L with a standard deviation of 31.9 g/L. Most sampling sets in HAA(5) molar concentration difference histogram were in the 0-0.25 mole/L range, with fourteen sampling sets. The average difference in HAA(5) effluent molar concentration was 0.04 mole/L with a standard deviation of 0.25 moles/L. Using the paired t-test method it was determ ined that there was no significant difference between the TRANS and OPAQ effl uent HAA(5) concentrations. 0 1 2 3 4 5 6 7 8 9 10 <=00-88-1616-24>24 HAA' ( g/L)# of Instances Figure 4-35. Difference in HAA(5) concentr ation between the TRANS and OPAQ sides (TRANS-OPAQ) separated into mass concentration ranges.

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83 0 2 4 6 8 10 12 14 <=00-0.250.25-0.500.50-0.75>0.75 HAA' ( moles/L)# of Instances Figure 4-36. Difference in HAA(5) concentr ation between the TRANS and OPAQ sides (TRANS-OPAQ) separated into molar concentration ranges. The HAA(5) concentration differences histogr ams are visually similar to those of for the HAA(5) concentration differences histogr ams but are slightly shifted in favor of a greater difference in the OPAQ and TRANS basi n effluent concentrations. This results from the normalization process, for every sampling set where the OPAQ basin effluent free chlorine residual was higher that that of the TRANS basin the HAA(5), DCAA, formation equation favored a higher OPAQ effluent HAA(5) concentration over the TRANS basin effluent. However, since th e opposite was the case, the OPAQ basin had in all but the three sampling sets a higher fr ee chlorine effluent residual than the TRANS basin, the normalization factor for free chlorine residual was, in all but those three sampling sets, less than one. In the twenty -seven sampling sets where the OPAQ basin effluent free chlorine residual was greater th an that of the TRANS basin, the OPAQ basin effluent HAA(5) concentrati ons were greater than the raw, non-normalized, effluent HAA(5) concentrations which in turn incr eased the difference in the TRANS and OPAQ basin effluent concentrations for those sampling sets.

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84 The difference in HAA(5) effluent mass and molar concentrations was plotted versus the average UV radiation exposure of th e wastewater while in the pilot basin, over the HRT (Figure 4-37 and Figure 4-38), respec tively. According to the paired t-test method, using the Pearson product momentum correlation coefficient, there was no linear correlation between the difference in effluent HAA(5) mass or molar concentrations and the average UV radiation exposure wh ile in the pilot basins, the HRT. -100.0 -75.0 -50.0 -25.0 0.0 25.0 50.0 75.0 100.0 0.001.002.003.004.005.00 Avg UV Radiation (mW/cm2)HAA' ( g/L) Figure 4-37. Difference in HAA(5) effluent mass concentration of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus the average UV radiation exposure over the HRT. -0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60 0.80 0.001.002.003.004.005.00 Avg UV Radiation (mW/cm2)HAA' ( moles/L) Figure 4-38. Difference in HAA(5) efflue nt molar concentration of the TRANS and OPAQ basins (TRANS-OPAQ) plotted versus the average UV radiation exposure over the HRT.

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85 Though the average difference between the TRANS and OPAQ basin were negative for the HAA(5) effluent concentr ations showing on average that the OPAQ basin had a higher HAA(5) effl uent concentration than the TRANS basin the average difference was positive for the HAA(5) efflue nt concentrations. Showing that when differences in free chlorine residual were taken into account the TRANS basin effluent HAA(5) concentration exceeded that of the OP AQ basin. Though the paired t-test did not show a statistical difference betw een the OPAQ and TRANS basin HAA(5) and HAA(5) effluent concentration th e number of sampling sets where the TRANS basin had a higher effluent concentration than the OPAQ basin were greater.

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86 CHAPTER 5 DISCUSSION: FULL-SCALE STUDY As stated previously, the North chlorine contact basin was studied in the full-scale experiments. The North basin flow splits into two parallel streams directly after entering the basin, after a mixing zone. The North ba sin plan view as well as the full-scale study sampling points are shown in Figure 3-4. A gate is also present that enables the possibility of having one side operational while the other is serviced or given routine maintenance. One side of the basin was covered with polypropylene tarps that prevent solar radiation exposure of the wastewater. In this discussi on the side covered with the tarps was termed the COV side. The other side of the basin that was left uncovered allowed for the solar radiation exposure of the wastewater and was termed the UNCOV basin. For consistency, the comparisons between the UNCOV and COV sides of the basin in all cases have the COV side effluent concentra tion subtracted from the UNCOV side effluent concentration. The paired t-te st statistical analysis, along with the Pearson product momentum correlation coefficient, va lues used in the following full-scale study discussion can be found in Appendix H. Chlorine Residual Free Chlorine The effluent free chlorine residual data for the UNCOV and COV side streams are partitioned into range increments in a histog ram for comparison (Figure 5-1). The most samples were in the 2.5-3.0 mg/L Cl2 residual range increment for the COV side. The

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87 UNCOV side of the basin had the same number of samples, three, in the 1.5-2.0, 2.0-2.5, and the 2.5-3.0 mg/L Cl2 ranges. The COV side had more samples than the UNCOV in the 2.5-3.0 mg/L Cl2. In the >3.0 mg/L Cl2 range the COV effluent had two samples while the UNCOV effluent did not have a free ch lorine residual that high. This point is significant because of the chlorine resi dual requirement desc ribed earlier; a higher chlorine residual ensures a great disinfection potential. 0 1 2 3 4 5 6 7 1.0-1.5 1.5-2.02.0-2.52.5-3.0>3.0 Free Chlorine (mg/L Cl2)# of Instances UNCOV Free Cl2 COV Free Cl2 Figure 5-1. Free chlorine resi dual of the UNCOV and COV side effluents separated into concentration ranges. The difference in free chlorine of the UNCOV and the COV side was split into concentration ranges and plotted in a histogram (Figure 5-2). In all sampling sets, the COV side had a higher free chlo rine residual than the UNCOV side. The range with the most numerous sampling sets was at the .0 to .75 and the .50 to .25 mg/L Cl2 ranges, with 3 samples each. The average difference of free chlorine residual between the UNCOV and COV sides for the 9 full-sca le sampling sets was .71 mg/L Cl2 with a

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88 standard deviation of 0.25 mg/L Cl2. Results from the statistical analysis, using the paired t-test method, indicate that there wa s a 99% confidence that the COV and UNCOV side effluent free chlorine residuals were statistically different. Thus the cover over the COV side stream helped to lower free chlorine loss from the UV radiation reduction reaction, shown in (Equation 1-1). 0 1 2 3 4 5 6 <-1.0-1.0-0.75-0.75-0.50-0.50-0.25>-0.25-0 Free Chlorine (mg/L Cl2)# of Instances Figure 5-2. Difference in free chlorine residual between the UNCOV and COV sides (UNCOV-COV) separated into concentration ranges. The difference in the free chlorine residual of the UNCOV and COV basin sides was plotted versus the difference in temperat ure between the sides (F igure 5-3). Six of the nine points were in the fourth quadrant, showing that in most cases the UNCOV side of the basin had a higher efflue nt temperature and a lower effluent free chlorine residual than the COV side. Using the paired t-test method, with the Pearson product momentum correlation coefficient, there was no significan t linear correlation between the difference in effluent free chlorine concentration and the difference in temperature.

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89 -1.20 -1.00 -0.80 -0.60 -0.40 -0.20 0.00 -0.50.00.51.0 Temperature (C)Free Chlorine (mg/L Cl2) Figure 5-3. Free chlorine difference of th e UNCOV and COV basin sides plotted versus the difference in temperature. A greater difference in effluent temperature was observed in the pilot study than in the full-scale study. There are two explanations for this phe nomenon. First, the larger quantity of water used in the full-scale st udy over the pilot-study helped to reduce the temperature increase caused by solar radiation exposure. Se cond, only the first chlorine contact basin, in the series of two basins, was observed in the full-scale study thus the contact time of the solar radiation and the wa stewater, the HRT, was less in the full-scale study than the pilot study. Total Chlorine The effluent total chlorine residual data for the UNCOV and COV sides are partitioned into range increments for comparison (Figure 5-4). The samples were in the 3.25 to 3.50 mg/L Cl2 residual range increment for th e UNCOV side. The COV side did not have a large number of samples in one in cremental range but rather had two samples

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90 in the 0.25 to 3.50 mg/L Cl2 residual range, four samples in the 3.75 to 4.00 mg/L Cl2 residual range, and three samples in the >4.00 mg/L Cl2 residual range. It was also apparent that the COV side produced more sa mples in the higher concentration ranges than the UNCOV side. As stated before, since the total chlorine residual is composed mostly of free chlorine the results were sim ilar to those shown for free chlorine residual. 0 1 2 3 4 5 6 7 8 3.0-3.253.25-3.53.5-3.753.75-4.0>4.0 Total Chlorine (mg/L Cl2)# of Instances UNCOV Total Cl2 COV Total Cl2 Figure 5-4. Total chlorine residual of the UNCOV and COV side effluents separated into concentration ranges. The difference in the total chlorine re sidual of the UNCOV and COV basin sides was plotted versus the difference in temperatur e between the sides (Figure 5-5). Seven of the nine points were in the fourth quadrant, showing that in most cases the UNCOV side of the basin had a higher effluent temperature and a lower effluent total chlorine residual than the COV side. Using the paired t-test method, with the Pearson product momentum correlation coefficient, there was no significan t linear correlation between the difference in effluent total chlorine concentration and the difference in temperature.

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91 -1.00 -0.80 -0.60 -0.40 -0.20 0.00 -0.50.00.51.0 Temperature (C)Total Chlorine Residual (mg/L Cl2) Figure 5-5. Total chlorine difference of the UNCOV and COV basin sides plotted versus the difference in temperature. Disinfection By-Products Trihalomethane As stated previously, the TTHM concentration of an effluent sample is the summed values of the chloroform, bromodichloromethane, dibromochloromethane, and bromoform concentrations calculated for the said sample using the GC/MS equipment. The THM speciation for each of the sampling full-scale runs can be seen in Appendix F. The TTHM effluent mass concentrations we re separated into range increments and plotted in a histogram (Figure 5-6). The con centrations are raw values in that they were not normalized to pH, temperature, and chlori ne effluent concentration. The COV side had the most numerous samples in the 25-50 g/L TTHM concentration range with four samples. Also, the COV side TTHM effluent concentrations had three samples in the 75100 g/L range. The UNCOV side of the basin had equal number of samples, three, in the 25-50 g/L and 50-75 g/L TTHM effluent concentration ranges. In the highest

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92 range increment, >100 g/L, the UNCOV side had two samples and the COV side only had one sample. It appears that the efflue nt TTHM concentrations for the full-scale study were only slightly higher than what was seen in the pilot study. However, in the full-scale plant the wastewater would flow through a second chlorine contact basin, prior to discharge or reuse, adding a dditional time for DBP formation. 0 1 2 3 4 5 6 <2525-50 50-75 75-100>100 TTHM ( g/L)# of Instances UNCOV TTHM COV TTHM Figure 5-6. The TTHM effluent mass con centrations for the UNCOV and COV sides are shown in range increments. The TTHM effluent molar concentrations were separated into range increments and plotted in a histogram (Figure 5-7). The UNCOV and COV sides both had the most numerous samples in the 0.25-0.50 moles/L TTHM concentration range with five samples each. In the second highest range increment, 0.75-1.00 moles/L, the UNCOV side had two samples and the COV side had three samples.

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93 0 1 2 3 4 5 6 <0.250.25-0.50 0.50-0.75 0.75-1.0>1.0 TTHM ( moles/L)# of Instances UNCOV TTHM COV TTHM Figure 5-7. The TTHM effluent molar concentrations for the UNCOV and COV sides are shown in range increments. The difference in the UNCOV and COV TTHM mass and molar effluent concentrations for all of the full-scale basin experimental runs is shown as a histogram (Figure 4-14 and 4-15), respectively. The di fferences in TTHM concentrations were the actual concentrations in the effluent sample; the concentrations were not normalized for the differences in chlorine residual, temperature or pH. There were five sampling sets of a total of nine experimental sampling sets where the COV basin side had a higher TTHM concentration than the UNCOV side. In the rest of the nine sampling sets the UNCOV side effluent concentration was higher than that of the COV side. The average difference of effluent TTHM mass concentration between the UNCOV and COV sides for the full-scale sampling sets was -2.24 g/L with a standard deviation of 9.5 g/L. The average difference of effluent TTHM mo lar concentration between the UNCOV and COV sides for the full-scale sampling sets was .02 moles/L with a standard deviation

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94 of 0.08 moles/L. According to the paired t-test using the Pearson product momentum correlation coefficient, there was no signifi cant difference between the TTHM effluent concentration of the UNCOV and COV sides, mass or molar. 0 1 2 3 4 5 6 <00-8 8-16 >16 TTHM ( g/L)# of Instances Figure 5-8. Difference in TTHM concentration between the UNCOV and COV sides (UNCOV-COV) separated into mass concentration ranges. 0 1 2 3 4 5 6 <00-0.07 0.07-0.14 >0.14 TTHM ( moles/L)# of Instances Figure 5-9. Difference in TTHM concentration between the UNCOV and COV sides (UNCOV-COV) separated into molar concentration ranges.

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95 The difference in the UNCOV and COV TTHM mass and molar effluent concentrations for all of the full-scale experi mental runs was plotted versus the difference in free chlorine residual (Figure 5-10 a nd Figure 5-11), respectively. The COV side effluent TTHM concentration was higher than the UNCOV side effluent concentration in five sampling sets out of the nine. Of these five sampling sets, four occurred when the effluent free chlorine residual difference between the sides was larger than the average residual difference of .71 mg/L. Th e average difference in the TTHM effluent concentrations between the UNCOV and COV sides was .24 g/L with a standard deviation of 9.5 g/L. The average difference in the TTHM effluent concentrations between the UNCOV and COV sides was .02 moles/L with a standard deviation of 0.08 moles/L. According to the paired t-test, with the Pearson product momentum correlation coefficient, there was no significant correlation between the difference in TTHM, mass or molar, effluent concentra tions and the difference in free chlorine residual. -20 -15 -10 -5 0 5 10 15 20 -1.50-1.00-0.500.00 Free Chlorine (mg/L)TTHM ( g/L) Figure 5-10. Difference in the TTHM effluent mass concentration between the UNCOV and COV sides (UCOV-COV) plotted versus the difference in free chlorine residual of the UNCOV and COV sides (UCOV-COV).

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96 -0.15 -0.10 -0.05 0.00 0.05 0.10 0.15 -1.50-1.00-0.500.00Free Chlorine (mg/L)TTHM (moles/L) Figure 5-11. Difference in the TTHM effl uent molar concentration between the UNCOV and COV sides (UCOV-COV) plotted versus the difference in free chlorine residual of the UNCOV and COV sides (UCOV-COV). The THM formation for all of the sampling runs for both the UNCOV and COV sides were, for the most part, as the chlorofo rm molecule. Chloroform made up at least 70%, by mass, of the TTHM formed for both sides of the basin during each of the sampling runs of the full-scale study (Figure 5-12). 84% 16% 0% 0% Chloroform Bromodichloromethane Dibromochloromethane Bromoform Figure 5-12. Speciation of the TTHM formed in the UNCOV side sampled at 9 am on August 25, 2004.

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97 The average, minimum, and maximum values of the normalization factors used to normalize the COV effluent TTHM concentrations to the UNCOV effluent TTHM concentrations are shown in (Table 5-1). The normalized TTHM concentrations will be denoted as TTHM. All TTHM normalized data can be found in Appendix D. The difference in temperature of the two sides di d not exceed 1.0 C and thus temperature did not have as great an effect on TTHM concentra tion differences as it did in the pilot basin study. As in the pilot study, the COV side of the basin maintained higher effluent free chlorine residuals, as much as 1.05 mg/L Cl2 higher than the UNC OV side, and thus had a greater effect on TTHM concentration differen ces. The relative effect of parameters on the TTHM concentration differences is reflec ted in the normalization factors, the more the factors deviate from 1.0 the greater the effect that parameter had on the TTHM concentration difference. The free chlorine residual normalization fact or deviates the most from 1.0, with a value of 0.85, and thus was the determin ing factor in the difference of the TTHM concentration between the two sides. The chlo rine residual having the greatest effect on the TTHM concentration difference of the two sides was important in that in all of the sampling sets the COV side had a higher efflue nt free chlorine residual than the UNCOV side. Table 5-1. Normalization factors used to normalize COV TTHM effluent concentrations to UNCOV TTHM effluent concentrations. pH Normalization Factor Temperature Normalization Factor Chlorine Residual Normalization Factor COV COV COV Average 1.00 1.01 0.85 Maximum 1.04 1.03 0.94 Minimum 0.99 0.99 0.74

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98 The effluent TTHM mass concentration data for the UNCOV and COV sides are partitioned into range increments for comparison (Figure 5-13). The most TTHM concentration samples for the COV side effluent were in the 25-50 g/L TTHM range increment, with four samples. The UNCOV side effluent had the most numerous samples in the both the 25-50 g/L and the 50-75 g/L TTHM range increments, both with three samples. It is also worth noti ng that at the UNCOV side of the basin had two samples where the TTHM concentration was greater than 100 g/L. 0 1 2 3 4 5 6 <2525-50 50-75 75-100>100 TTHM' ( g/L)# of Instances UNCOV TTHM' COV TTHM' Figure 5-13. The TTHM mass concentration instances separated into concentration ranges for the UNCOV and COV side. The effluent TTHM molar concentrati ons for the UNCOV and COV sides are partitioned into range increments for comparison (Figure 5-14). Most TTHM concentration samples for the UNCOV and COV side effluents were in the 0.25 to 0.50 moles/L TTHM range increment, with 5 and 6 samples, respectively. It is also worth

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99 noting that at the highest concentration increment the UNCOV side had two samples while the COV side had only one. 0 1 2 3 4 5 6 7 <0.250.25-0.50 0.50-0.75 0.75-1.0>1.0 TTHM' ( moles/L)# of Instances UNCOV TTHM' COV TTHM' Figure 5-14. The TTHM molar concentrati on instances separated into concentration ranges for the UNCOV and COV side. The difference in the effluent TTHM concentrations between the UNCOV and COV sides was separated into mass concentr ation ranges (Figure 515). The histogram shows that in only two sampling sets, out of a total of nine sampling sets, did the COV side have a higher TTHM concentration than the UNCOV side. Most differences in the effluent TTHM mass concentrations were in the 8 to 16 g/L range. The average difference of normalized TTHM mass con centration between the UNCOV and COV sides for the full-scale study was 7.48 g/L with a standard deviation of 9.17 g/L. Using the paired t-test method there was a 95% confidence level that there was a difference between the UNCOV side effluent TTHM concentrations and the COV side effluent TTHM concentrations. Thus, when the effluent TTHM concentrations are

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100 normalized to account for the difference in TTHM forming parameters between the two basin side streams the difference can be shown to be significant. 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 <00-8 8-16 >16 TTHM' ( g/L)# of Instances Figure 5-15. Difference in TTHM con centration between the UNCOV and COV sides (UNCOV-COV) separated into mass concentration ranges. The difference in the effluent TTHM concentrations were separated into molar concentration ranges (Figure 5-16). The hist ogram shows that in only two sampling sets, out of a total of nine sampling sets did the COV side have a higher TTHM concentration than the UNCOV side. Most sampling sets of the TTHM molar concentration difference were in the 0.07 to 0.14 moles/L range. The average difference of normalized TTHM concentration between the UNCOV and COV sides for the full-scale study was 0.06 moles/L with a standard deviation of 0.07 moles/L. Using the paired t-test method there was a 95% confidence level that there was a difference between the UNCOV side effluent TTHM molar concentrations and the COV side effluent TTHM concentrations.

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101 0 1 2 3 4 5 <00-0.07 0.07-0.14 >0.14 TTHM' ( moles/L)# of Instances Figure 5-16. Difference in TTHM con centration between the UNCOV and COV sides (UNCOV-COV) separated into molar concentration ranges. Through the normalization of the effluent TTHM concentration the number of sampling sets where the COV side had a higher TTHM concentration than the UNCOV side was reduced from five to only two, mo stly resulting from the difference in free chlorine residual. Thus, in the majority of the sampling sets the UNCOV, UV radiation irradiated, side had a higher TTHM effluent concentration. The TTHM effluent concentrations demonstrate and supp ort the findings of the 2002 IPPD team2, that UV radiation, and more simply covering the ch lorination process, not only provides the benefit of a higher free chlorine residual but also the tendency toward a lower TTHM effluent concentration. Haloacetic Acid As stated previously, the HAA(5) concentr ation of an effluent sample is the summed values of the monochloroacetic acid (MCAA), monobromoacetic acid (MBAA), dichloroacetic acid (DCAA), dibromoacetic acid (DBAA), and trichloroacetic acid (TCAA) concentrations calculated for the said sample using the GC/ECD. The THM speciation for each of the sampling full-scale runs can be seen in Appendix F.

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102 The HAA(5) effluent mass concentrati ons for the UNCOV and COV sides were separated into range increments and plot ted in a histogram (Figure 5-17). The concentrations are raw values in that they were not normalized to temperature or chlorine residual. Most of the effluent HAA(5) c oncentrations fell within the greater than 100 g/L range for the UNCOV and COV sides, w ith seven and six samples respectively. The HAA(5) effluent molar concentrations we re separated into ra nge increments and plotted in a histogram (Figure 5-18). Most of the effluent HAA(5) concentrations fell within the 0.75 to1.0 moles /L range for the UNCOV side while the most instances for the COV side occurred in the 0.50 to 0.75 a nd the 0.75 to1.0 moles/L range, both with four samples. The UNCOV side effluent sample for HAA(5) concentration for August 25, 2004 at 9 am was lost so it was not include d in the histograms. It is good to note that the majority of the UNCOV and COV side HAA(5 ) effluent concentrations fall in the range that is greater the proposed EPA standard. The HAA(5) effluent concentrations were greater than those found in the pilot st udy and since the chlorine disinfection basins are in series the wastewater will pass through a second basin prior to discharge, or reuse, adding more time for DBP formation. 0 1 2 3 4 5 6 7 <2525-50 50-75 75-100>100 HAA ( g/L)# of Instances UNCOV HAA COV HAA Figure 5-17. The HAA(5) effluent mass concentrations for the UNCOV and COV sides are shown in range increments.

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103 0 1 2 3 4 5 6 <0.250.25-0.50 0.50-0.75 0.75-1.0>1.0 HAA ( moles/L)# of Instances UNCOV HAA COV HAA Figure 5-18. The HAA(5) effluent molar concentrations for the UNCOV and COV sides are shown in range increments. The difference in the HAA(5) concentrations (HAA(5)) were separated into mass and molar concentration ranges in (Figur e 5-19 and 5-20), respectively. The UNCOV side effluent sample for HAA(5) concentrati on for August 25, 2004 at 9 am was lost so it was not included in the histograms. In eigh t of the nine sampling sets the UNCOV side effluent HAA(5) mass concentration wa s higher than the COV side effluent concentration, one sampling set was not us ed in the analysis since the UNCOV side sample was lost. In the HAA(5) mass concentr ation difference histogram the most values were in the greater than 16 g/L range, with four sampling sets. The average difference in HAA(5) effluent mass concentration was 39.5 g/L with a standard deviation of 35.2 g/L. In six of the nine sampling se ts the UNCOV side effluent HAA(5) molar concentration was higher than the COV side effl uent concentration. In the histogram of the differences in HAA(5) effluent molar con centration the values were spread evenly across the concentration ranges. The aver age difference in HAA(5) effluent molar

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104 concentration was 0.16 mole/L with a standard deviation of 0.25 moles/L. Using the paired t-test method it was determined th at there was a 99% confidence that the difference between the UNCOV and COV side effluent HAA(5) mass concentrations were significant. There was a 95% confidence that there was a significant difference in the HAA(5) effluent molar concentrations. 0 1 2 3 4 5 6 7 <00-8 8-16 >16 HAA ( g/L)# of Instances Figure 5-19. Difference in HAA(5) concen tration between the UNCOV and COV sides (UNCOV-COV) separated into mass concentration ranges. 0 1 2 3 4 <00-0.07 0.07-0.14 >0.14 HAA ( moles/L)# of Instances Figure 5-20. Difference in HAA(5) con centration between the UNCOV and COV sides (UNCOV-COV) separated into molar concentration ranges.

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105 The difference in HAA(5) effluent mass concentrations of the UNCOV and COV sides was plotted versus the difference in free chlorine residual of the UNCOV and COV sides (Figure 5-21). As stated previously, in eight of the nine sampling sets the UNCOV side HAA(5) effluent mass concentrations were higher than those of the COV side. Using the paired t-test method, with th e Pearson product momentum correlation coefficient, it was determined that there was no significant correlation between the difference in effluent HAA(5) mass concentr ation and the difference in free chlorine residual. Even though there doe s not appear to be a linea r correlation between the difference in effluent HAA(5) concentration a nd the difference in e ffluent free chlorine residual the largest differen ce in effluent HAA(5) concentration does corresponds with the largest difference in effluent free chlorine residual. 0 20 40 60 80 100 120 0.001.002.003.004.00 Free Chlorine (mg/L Cl2)HAA ( g/L) Figure 5-21. Difference in HAA(5) efflue nt mass concentration of the UNCOV and COV sides versus the difference in free chlorine residual of the UNCOV and COV sides. The difference in HAA(5) effluent molar concentrations of the UNCOV and COV sides was plotted versus the difference in free chlorine residual of the UNCOV and COV sides (Figure 5-22). Similar to the mass c oncentration, using the paired t-test method,

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106 with the Pearson product momentum correlation coefficient, it was determined that there was no significant linear correlation between the difference in effluent HAA(5) molar concentration and the difference in free chlo rine residual. Again, it was observed that though there was no significant linear relations hip between the difference in HAA(5) and the difference in free chlorine residual, th e largest difference in effluent HAA(5) concentration corresponds with the largest difference in effluent free chlorine residual. -0.10 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.001.002.003.004.00 Free Chlorine (mg/L Cl2) HAA ( mole/L) Figure 5-22. Difference in HAA(5) efflue nt molar concentration of the UNCOV and COV sides versus the difference in free chlorine residual of the UNCOV and COV sides. The HAA(5) speciation for the sampling runs for both the UNCOV and COV sides is shown in Appendix F No single species made up the majority of the HAA(5) concentration in all of the sampling sets though it did appear that DCAA made up the highest percentage for the greatest number of sets compared with the other HAA(5) species. The speciation of the HAA(5) efflue nt concentration in the COV side on August 25, 2004 taken at 12 pm is shown with species percentage (Figure 5-23). In this case, DCAA made up 59% of the HAA(5) mass concen tration. In this sample there was no measurable MCAA or DBAA present.

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107 0% 8% 59% 0% 33% MCAA MBAA DCAA DBAA TCAA Figure 5-23. Speciation of the HAA(5) form ation in the COV effluent on a mass basis sampled at 12 pm on August 25, 2004. Like THM formation, HAA(5) formation is affected by environmental conditions, such as, temperature and free chlorine residual. In order to compensate for the differences between these parameters in the North basin effluents the HAA(5) concentrations were normalized like in the pilot study. All HAA(5) normalized data can be found in Appendix D. Though DCAA did not make up the highest percentage in all sampling sets it did make up the highest pe rcentage of the HAA(5) concentrations in most cases and thus the formation equati on coefficients for DCAA was used in the normalization of the COV side effluent HAA(5) concentration to the UNCOV side effluent HAA(5) concentration. The average, minimum, and maximum values of the normalization factors used to normalize the COV effluent HAA(5) concen trations to the UNCOV effluent HAA(5) concentrations are shown in (Table 5-2). Th e average values give an idea of how much the difference in the parameter affects the HAA(5)concentration of the two sides. As stated previously, the farther the normali zation factor is from 1.0 the greater the parameter contributes to the HAA(5) concentr ation difference between the two sides.

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108 The free chlorine residual normalization factor deviates the most from 1.0, with a value of 0.87, and thus was the determining factor in the difference of the HAA(5) concentration between the two sides accordi ng to the model. The chlorine residual having the greatest effect on the HAA(5) con centration difference of the two sides was important since in all cases the COV side had a higher free chlorine resi dual effluent than the UNCOV side, and in all but two sampli ng sets the UNCOV side had a higher HAA(5) effluent concentration than the COV side. Table 5-2. Normalization factors used to normalize COV HAA(5) effluent concentrations to UNCOV HAA(5) efflue nt concentrations. Temperature (C) Normalization Factor Chlorine Residual Normalization Factor COV COV Average1.01 0.87 Maximum1.02 0.95 Minimum0.99 0.78 The HAA(5) effluent mass concentrations were separated into range increments and plotted in a histogram (Figure 5-24). The UNCOV side effluent sample for HAA(5) concentration for August 25, 2004 at 9 am wa s lost so it was not included in the histograms. Similar to the raw HAA(5) histogram, most of the effluent HAA(5) concentrations fell within the greater th an 100 g/L range for the UNCOV side, with seven samples. However, for the COV side most values fell within the 75 to 100 g/L HAA(5) effluent concentration ra nge, with four samples. The HAA(5) effluent molar concentrations were separated into range incr ements and plotted in a histogram (Figure 5-25). Most of the effluent HAA(5) molar concentrations fe ll within the 0.75 to 100 moles/L range for the UNCOV side, with five samples. The COV side HAA(5)

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109 effluent concentrations fell mostly in th e 0.50 to 0.75 moles/L range, with seven samples. It is significant to note that the UNCOV side had more concentration values fall within the greater than 100 g/L than the COV side. Also, the UNCOV side had one sample in the greater than 1.0 moles/L range where the COV side had none and the UNCOV side had more values in the second to highest range, 0.75 to 1.0 moles/L range, than the COV side, with five and one samples respectively. 0 2 4 6 8 <2525-50 50-75 75-100>100 HAA' (g/L)# of Instances UNCOV HAA' COV HAA' Figure 5-24. The HAA(5) effluent mass concentrations for the UNCOV and COV basin sides are shown in range increments. 0 2 4 6 8 <0.250.25-0.50 0.50-0.75 0.75-1.0>1.0 HAA' ( moles/L)# of Instances UNCOV HAA' COV HAA' Figure 5-25. The HAA(5) effluent mo lar concentrations for the UNCOV and COV basin sides are shown in range increments.

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110 The difference in the HAA(5) concentrations (HAA(5)) were separated into mass and molar concentration ranges (Figure 526 and 5-27), respectively. In all of the nine sampling sets the UNCOV side efflue nt HAA(5) mass and molar concentration were higher than the COV side effluent concentration. In the HAA(5) mass concentration difference histogram the six samp ling sets were in the greater than 24 g/L range. The average difference in HAA(5 ) effluent mass concentration was 38.96 g/L with a standard deviation of 35.15 g/L. Most instances in HAA(5) molar concentration difference histogram were in the greater than 0.14 mole/L range, with five sampling sets. The average difference in HAA(5 ) effluent molar concentration was 0.24 mole/L with a standard deviation of 0.23 moles/L. Using the paired t-test method it was determined that there was a 99% confiden ce that there was a difference between the UNCOV and COV side effluent HAA(5) concentrations, mass and molar. 0 1 2 3 4 5 6 7 <00-8 8-16 >16 HAA' ( g/L)# of Instances Figure 5-26. Difference in HAA(5) con centration between the UNCOV and COV sides (UNCOV-COV) separated into mass concentration ranges.

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111 0 1 2 3 4 5 6 7 <00-0.07 0.07-0.14 >0.14 HAA' ( moles/L)# of Instances Figure 5-27. Difference in HAA(5) con centration between the UNCOV and COV sides (UNCOV-COV) separated into molar concentration ranges. In all of the nine sampling sets for the non-normalized and normalized, to temperature and free chlorine residual, HAA( 5) concentrations the UNCOV side had a higher HAA(5) mass concentration than the COV side. Also, all of the average HAA(5) concentrations, normalized and non-normalized, there was at least a 95% confidence that the difference was significant, for mass con centrations the confidence was 99%. Thus, preventing the UV radiation exposure of wast ewater during chlorine disinfection could result in lower HAA(5) formation than in the exposed chlorination process.

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112 CHAPTER 6 DISCUSSION: MEASURED PARAMETERS Other water quality parameters, such as, total coliform, total suspended solids (TSS), pH, conductivity, temperature, and di ssolved oxygen were measured during the pilot and full-scale studies. Measurement of these water quality parameters made it possible to determine the extent of the di fference between the conventional process of allowing the chlorine disinfection stage of the wastewater treatment process to be exposed to solar radiation, ultraviolet and globa l radiation, versus covering the basin thus preventing the exposure of the wastewater during the disinfection process. Temperature The temperature did not appear to have a great influence on the chlorine residual or on the difference in the TTHM or HAA(5) fo rmation between the UV radiation exposed and UV limited wastewater effluents. The te mperature parameter does not appear in the model equation for MCAA and the TTHM average normalization factor for temperature was 1.01 for the pilot system and 1.05 for th e full-scale system. The temperature values for the pilot and full-scale studies can be viewed in the Appendix E and F, for the pilot and full-scale studies respectively. Total Coliform In almost all cases in both the pilot a nd full-scale studies th e total coliform counts were less than the detectable limit, 1/100 mL, for both th e UV radiation exposed and UV limited wastewater effluents. The total colif orm values for the pilot and full-scale studies for the following water quality parameters can be viewed in the Appendix E and F,

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113 respectively. An example of typical total co liform values is shown in (Figure 6-1), the values are samples taken from July 14, 2004. The facts that in all sampling cases effluent total coliform counts were less than the de tectable limit demonstrates that both systems, the solar radiation exposed and protecte d, produce adequate disinfection. 0.00 0.02 0.04 0.06 0.08 0.10 0.12 9:0012:0014:00 Time of Day (hr:min)Total Coliform (#/100 mL)25 27 29 31 33Temperature (C) TRANS TC OPAQ TC TRANS Temp OPAQ Temp Figure 6-1. Total coliform and temperatur e plotted against sampling time on July 14, 2004. Total Suspended Solids In almost all cases in both the pilot and full-scale studies the total suspended solids concentrations were less than the detectable limit, 1 mg/L TSS, for both the UV radiation exposed and limited wastewater effluents. The TSS values for the pilot and full-scale studies can be viewed in the Appendix E and F, respectively. An example of typical TSS values is shown in (Figure 6-2), the values are samples taken from July 14, 2004. Both the solar radiation exposed and protected wa stewater chlorine disinfection systems had less than detectable effluent TSS concentra tions demonstrating that both systems would perform adequately with respect to TSS effluent concentration.

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114 0.00 0.20 0.40 0.60 0.80 1.00 1.20 9:0012:0014:00 Time of Day (hr:min)TSS (mg/L)25 27 29 31 33Temperature (C) INT TSS TRANS TSS OPAQ TSS TRANS Temp OPAQ Temp Figure 6-2. Total suspended solids and temperature plotted against sampling time on July 14, 2004. pH The pH did not appear to have a great influence on the difference in the TTHM or HAA(5) formation between the solar radia tion exposed and protected wastewater effluents, since for both DBPs the average norm alization factor was 1.00. The pH values for the pilot and full-scale studies can be viewed in the Appendix E and F, for the pilot and full-scale studies respectively. An example of typical pH values is shown in (Figure 6-3), the values are samples taken from July 14, 2004. 6.5 6.8 7.0 7.3 7.5 9:0012:0015:00 Time of Day (hr:min)pH25 27 29 31 33Temperature (C ) INT pH TRANS pH OPAQ pH TRANS Temp OPAQ Temp Figure 6-3. pH and temperature plotte d against sampling time on July 14, 2004.

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115 Conductivity The conductivity did not appear to have a great influence on the chlorine residual or on the difference in the TTHM or HAA(5) fo rmation between the UV radiation exposed and UV limited wastewater effluents. The c onductivity values for th e pilot and full-scale studies can be viewed in the Appendix E a nd F, for the pilot and full-scale studies respectively. An example of typcal conductiv ity values is shown in (Figure 6-4), the values are samples taken from July 14, 2004. 550 600 650 700 750 800 9:0012:0015:00 Time of Day (hr:min)Conductivitys ( mhos/cm)25 27 29 31 33Temperature (C) INT Cond TRANS Cond OPAQ Cond TRANS Temp O PA Q T e m p Figure 6-4. Conductivity and temperature plotted against sampling time on July 14, 2004. Dissolved Oxygen The dissolved oxygen did not appear to have a great influence on the chlorine residual or on the difference in the TTHM or HAA(5) formation between the UV radiation exposed and UV limited wastewater ef fluents. The dissolved oxygen values for the pilot and full-scale studies can be viewed in the Appendix E and F, for the pilot and full-scale studies respectively. An example of typical dissolved oxygen values is shown in (Figure 6-5), the values are sample s taken from July 14, 2004. The DO effluent

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116 concentrations did not vary greatly between the solar radiation exposed and protected systems. 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 9:0012:0015:00 Time of Day (hr:min)Dissolved Oxyge n (mg/L O2)25 26 27 28 29 30 31 32 33 34Temperature (C) INT DO TRANS DO OPAQ DO TRANS Temp OPAQ Temp Figure 6-5. Dissolved oxygen and temperatur e plotted against sampling time on July 14, 2004.

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117 CHAPTER 7 CONCLUSIONS The KWRF is mandated to maintain no less than 1 mg/L chlorine residual as the wastewater exits the chlorine disinfection basins. While in the chlorine contact basins the wastewater is left exposed to ultraviolet radi ation, which catalyzes the reduction of free chlorine to the chloride ion. In order, to compensate for the loss in chlorine through this mechanism additional chlorine must be adde d to ensure sufficient disinfection and effluent chlorine residual. In pilot and full-scale studies, the significance of shielding the wastewater during chlorine disinfection was tested. In one process stream, the wastewater was left exposed; whereas in th e second process stream an opaque cover was used to shield the wastewater during chlorine disinfection from ultraviolet radiation. It was found that the wastewater effluent from the opaquely covered chlorination process had higher total and free chlorine residuals. Us ing the paired t-test method for statistical data analysis, there was a 99% confidence that the effluent chlorine residuals of the two process streams were different, for both th e pilot and full-scale study. Preventing ultraviolet radiation exposure of wastewat er during chlorine di sinfection provides for higher chlorine residual and reduces the need for chlorine compensation caused by exposure. In order to ascertain the cause of the diffe rence in effluent chlorine residuals linear correlations were tested for temperature and ul traviolet radiation, for the pilot study. The Pearson product momentum correlation coefficient with the paired t-test analysis was used to determine the confidence of the correl ation. There was a 95% confidence that the

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118 difference in free chlorine residual correlated linearly with the difference in effluent temperature. There was no confidence that there was a linear correlation between the difference in total chlorine residual and the difference in effluent temperature. There was a 95% confidence that there was a linear corr elation between both the difference in free and total chlorine residual with the difference in average ultraviolet radiation exposure. Also found, was a 99% confidence in a lin ear correlation between the effluent temperature of the exposed and non-exposed pi lot basins with the average ultraviolet radiation exposure. As ultr aviolet radiation intensity increased during the day the difference in effluent temperat ure would increase and the diffe rence in chlorine, total and free, would also increase. The extent of residual difference depends on the hydraulic retention time of wastewater in the basin, the in itial chlorine dosage, and the amount of ultraviolet radiation that the water will be exposed to while in the basin. Since ultraviolet radiation exposure of microorganism result in a degree of inactivation, preventing the ultraviolet radiation exposure of wastewater during chlorination becomes a concern over adequate disinfection. During the pilot and fullscale studies effluent samples were tested for total coliforms. In all sampling sets, both the ultraviolet radiation exposed and non-e xposed process streams provided adequate disinfection. Thus, preventi ng ultraviolet radiat ion exposure of wastewater does not compromise disinfection. Disinfection by-product formation is beco ming an ever-increasing concern and future regulations for stricter discharge concen trations have only yet to be implemented. Since chlorine disinfection l eads to DBP formation, the DBP formation of the exposed and non-exposed chlorination streams in the pilot and full-scale studies were also

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119 analyzed. Total trihalomethanes (TTHMs) and the regulated five haloacetic acids HAA(5)s were measured to evaluate DBP form ation for the pilot a nd full-scale studies. Both in the pilot and full-scale studies th ere was found no significant difference in the raw effluent TTHM concentrations between the UV exposed and non-exposed chlorine disinfection processes. However, the normalized TTHM effluent concentrations were statistically higher in the exposed chlorine disinfection process than the non-exposed process. Though there was no significant di fference in the raw TTHM concentrations there was a 99% and a 95% confidence th at the mass and molar TTHM effluent concentrations were different for the pilot a nd full-scale studies, respectively. Showing that there is significant evidence that shieldi ng the chlorine disinfection process not only results in a higher chlorine residual but also a lower TTHM concentration. In the pilot study for the raw and normalized HAA(5) concentrations their appeared to be no significant difference between the exposed and non-exposed processes. Although the non-exposed process provided for a hi gher chlorine residual it did not result in a higher HAA(5) concentration which is desi red if the process were to be implemented at the KWRF. However, for the full-scale study the HAA(5) effluent concentration was statistically higher in the exposed process over the non-exposed pro cess. Statistical analysis showed a 99% and a 95% confiden ce that the raw effluent HAA(5) mass and molar concentrations, respectively, were di fferent; providing s upport that the nonexposed wastewater not only provided higher chlorine resi dual but also less HAA(5) formation. Statistical analysis showed a 99% confidence that the normalized HAA(5) mass and molar concentrations were also differe nt. It is important to note that the fullscale study was performed on only the first por tion of the KWRF ch lorine disinfection

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120 process, the first of two chlorine contact basins in series. Thus, the difference in pilot and full-scale data is not unexpected since the hydr aulic retention used in the pilot study was not available during the full-sca le study. If the complete KWRF chlorine disinfection process were to be analyzed in future studies it would be expected th at the data would be more comparable to the data co llected during the pilot study. The data provided during the pilot and full-scale study have positively determined the following: 1. P reventing ultraviolet radiation exposure of wastewater during chlorine disinfection results in a higher effluent free and total chlorine residual 2. Preventing ultraviolet radiation exposure of wastewater significantly reduces the TTHM formation during chlorine disinfection 3. Preventing ultraviolet radiation exposure of wastewater doe s not result in an increase in HAA(5) formation 4. Preventing ultraviolet radiation exposure of wastewater during chlorine disinfection does not adversely affect microorganism inactivation. Because the findings of these studies pr ovide evidence against the more common theory behind DBP formation with respect to chlorine residual it is recommended that future studies concerning UV radiation e xposure and DBP formation be performed.

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121 APPENDIX A PILOT-SCALE BASIN DESIGN Table A-1. South chlorine contact basin Elevation Feet Side View: Outer Wall/Baffle 79.82 Inlet Weir 71.50 Effluent Weir 73.80 Bottom 64.57 Outer Wall/Baffle 15.25 Inlet Weir 6.93 Effluent Weir 9.23 Top View: Length w/o Thickness 93.00 Length w/ Thickness 95.67 Width w/o Thickness 77.33 Width w/ Thickness 80.00 Width of Channel 9.00 No. of channels 8.00 Area 7653 ft2 Volume 116712 ft3 Table A-2. North chlorine contact basin Actual Height (Feet) Side View: Outer Wall/Baffle 11.00 Inlet Weir 7.00 Effluent Weir 7.92 Top View: Length w/o Thickness 56.00 Length w/ Thickness 58.00 Width w/o Thickness 56.33 Width w/ Thickness 58.33 Width of Channels 5.00 No.of Channels 10.00 Area 3383 ft2 Volume 37216 ft3 Table A-3. Pilot basin. Basin (Scaled) Feet Length 4.000 Width 3.653 Height 0.693 No. Channels 9.000 Channel Width 0.362 Channel Width 4.344 in Area 14.610 ft2 Volume 10.123 ft3

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122 APPENDIX B FLUOROSCEIN TRACER ANALYSIS Table B-1. Fluoroscein tracer at KWRF pilot basin, clear top. Time sample collection Time Reading Fluoroscein Time/HRT h min min mg/L 4000.50.00960 35460.50.00960.056 348120.50.00960.112 342180.50.00960.168 336240.50.00960.224 330300.40.007680.28 324360.50.00960.336 318420.50.00960.392 312480.50.00960.448 36540.50.00960.504 30600.50.00960.56 256640.80.015360.597333 252681.40.026880.634667 248721.70.032640.672 244762.10.040320.709333 240802.60.049920.746667 236843.40.065280.784 232883.80.072960.821333 228924.10.078720.858667 224964.80.092160.896 2201004.80.092160.933333 2161045.20.099840.970667 2121085.10.097921.008 281125.30.101761.045333 241165.60.107521.082667 201205.60.107521.12 1561245.50.10561.157333 1521285.90.113281.194667 1481325.80.111361.232 1441365.80.111361.269333 1401405.60.107521.306667 1361445.70.109441.344 13214860.11521.381333 1281525.90.113281.418667

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123 Table B-1. Continued. Time sample collection Time Reading Fluoroscein Time/HRT h min min mg/L 1241565.70.109441.456 1201605.90.113281.493333 1161645.70.109441.530667 1121685.60.107521.568 181725.80.111361.605333 141765.50.10561.642667 101805.70.109441.68 05418660.11521.736 0481926.10.117121.792 0421985.80.111361.848 0362045.90.113281.904 0302105.80.111361.96 0242165.70.109442.016 0182225.50.10562.072 0122285.50.10562.128 062345.40.103682.184 002405.20.099842.24 Table B-2. Conditions during tracer analysis. Basin one Reactor 75Gal Flow Rate 42GPH HRT 1.79h Wastewater Flow Rate 84.0GPH Flow Rate 5.30L/min Flow Rate 0.451mg/L Fluoroscein Flow Rate 21.7mL/min Flow Rate 0.0217L/min Conc. 110.1455mg/L Conc. 0.110146g/L Pump 7

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124 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 00.511.522.5 Time of Sample (min) / HRT(min)Fluoroscein (mg/L) Figure B-1. Fluoroscein versus sampling time. Table B-3. Flouroscein F curve calculation. Time (min) [ ] mg/L F Time (min)[ ] mg/L F 00.0096 0.0871571160.107520.976163 60.0096 0.0871571200.107520.976163 120.0096 0.0871571240.10560.958732 180.0096 0.0871571280.113281.028458 240.0096 0.0871571320.111361.011026 300.00768 0.0697261360.111361.011026 360.0096 0.0871571400.107520.976163 420.0096 0.0871571440.109440.993595 480.0096 0.0871571480.11521.045889 540.0096 0.0871571520.113281.028458 600.0096 0.0871571560.109440.993595 640.01536 0.1394521600.113281.028458 680.02688 0.2440411640.109440.993595 720.03264 0.2963351680.107520.976163 760.04032 0.3660611720.111361.011026 800.04992 0.4532191760.10560.958732 840.06528 0.5926711800.109440.993595 880.07296 0.6623971980.111361.011026 920.07872 0.7146912040.113281.028458 960.09216 0.8367112100.111361.011026 1000.09216 0.8367112160.109440.993595 1040.09984 0.9064372220.10560.958732 1080.09792 0.8890062340.103680.9413 1120.10176 0.923869

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125 Table B-4. The F curve values. tm = 113 Min tm 2= 12822 2 =313 18 n = 41 CMFRs in Series t10= 61 Min -0.2 0 0.2 0.4 0.6 0.8 1 1.2 0204060 Time (min)F Figure B-2. The F curve.

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126 APPENDIX C CHLORINE DOSING CALCULATIONS Table C-1. Chlorine dosi ng during pilot-scale study. Date Qr Qw Cw Cr M/DD/YR GPH mL/min mg/L Cl2mg/L Cl2 6/23/2004 56 21 1350 8.03 6/30/2004 56 21 1350 8.03 7/7/2004 52 21 1253 8.02 7/13/2004 56 19.5 1350 7.45 7/26/2004 56 18.25 1350 6.97 7/28/2004 56 18.25 1350 6.97 8/2/2004 40 17 1350 9.09 8/4/2004 40 21 1401 11.66 8/9/2004 56 21 1153 6.85 8/16/2004 40 24 1716 16.32 Qr=Flow Rate of Wastewater to Reactors, Qw=Flow Rate of Chlorine Solution, Cw=Concnetration of Chlorine Solution, Cr=Concen tration of Chlorine going to Reactors Table C-2. Acid and base a ddition during pilot-scale study. Chemical Date Qr Qw Cw Cr Added M/DD/YR GPH mL/min Normal Normal H2SO4 7/26/2004 56 19.6 0.2 4.75E-04 NaOH 7/28/2004 56 19.6 0.2 4.75E-04

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127 APPENDIX D COMPILED DATA Table D-1. Pilot-scale study comp iled and calculated parameter data. Time Time pH TRANS pH OPAQ Temperature TRANS Temperature OPAQ M/DD/Yr hr:min (C) (C) 6/23/2004 9:00 6.85 6.86 27.2 27.0 6/23/2004 12:00 6.83 6.85 29.0 27.6 6/23/2004 14:00 6.87 6.78 30.3 29.2 6/30/2004 9:00 7.34 7.2 28.4 27.5 6/30/2004 12:00 7.3 7.37 30.4 29.6 6/30/2004 14:00 7.36 7.39 33.5 29.8 7/7/2004 9:00 7.29 7.23 28.3 28.1 7/7/2004 12:00 7.27 7.33 31.7 29.9 7/7/2004 14:00 7.33 7.35 33 29.8 7/14/2004 9:00 7.25 7.24 27.9 27.4 7/14/2004 12:00 7.22 7.27 31.2 28.5 7/14/2004 14:00 7.23 7.27 33.3 29.6 7/26/2004 9:00 6.63 6.64 28.1 27.9 7/26/2004 12:00 6.3 6.22 31.3 29.2 7/26/2004 14:00 6.07 6.5 33.5 29.9 7/28/2004 9:00 9.61 9.48 28.1 27.8 7/28/2004 12:00 9.3 8.92 31.0 30.0 7/28/2004 14:00 8.4 8.73 29.9 29.1 8/2/2004 9:00 7.2 7.2 28.1 28.0 8/2/2004 12:00 7.35 7.45 31.3 29.3 8/2/2004 14:00 7.53 7.53 33.0 29.8 8/4/2004 9:00 7.3 7.31 28.3 27.8 8/4/2004 12:00 7.08 7.1 31.2 29.4 8/4/2004 14:00 7.26 7.16 33.5 32.1 8/11/2004 9:00 7.05 7.04 27.4 27.4 8/11/2004 12:00 7.34 7.2 29.2 28.2 8/11/2004 14:00 7.59 7.24 30.6 28.9 8/16/2004 9:00 7.12 7.14 27.1 27.0 8/16/2004 12:00 7.26 7.48 30.4 28.3 8/16/2004 14:00 7.36 7.45 32.6 29.2

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128 Table D-2. Pilot-scale study compile d chlorine data and differences. Time Time Free Chlorine Residual TRANS Free Chlorine Residual OPAQ Total Cl2 Residual TRANS Total Cl2 Residual OPAQ Free Chlorine Residual (TRANSOPAQ) Total Chlorine Residual (TRANSOPAQ) M/DD/Yr hr:min mg/L Cl2mg/L Cl2mg/L mg/L mg/L mg/L 6/23/2004 9:00 1.05 1.30 3.05 3.25 -0.25 -0.20 6/23/2004 12:00 0.75 2.1 1.85 2.65 -1.35 -0.80 6/23/2004 14:00 0.25 1 1.4 2.1 -0.75 -0.70 6/30/2004 9:00 1.15 1.25 2.5 2.9 -0.10 -0.40 6/30/2004 12:00 1.00 1.55 2.45 2.8 -0.55 -0.35 6/30/2004 14:00 1.50 1.90 2.15 2.65 -0.40 -0.50 7/7/2004 9:00 4.10 4.90 5.2 5.75 -0.80 -0.55 7/7/2004 12:00 3.00 3.75 3.45 5.45 -0.75 -2.00 7/7/2004 14:00 2.85 4.3 3.85 5.1 -1.45 -1.25 7/14/2004 9:00 3.85 2.7 4.5 3.7 1.15 0.80 7/14/2004 12:00 1.9 2.25 2.8 2.35 -0.35 0.45 7/14/2004 14:00 1.1 1.85 1.55 2.5 -0.75 -0.95 7/26/2004 9:00 0.25 0.30 2.9 3 -0.05 -0.10 7/26/2004 12:00 0.35 0.55 1.05 1.3 -0.20 -0.25 7/26/2004 14:00 0.95 1.1 1.65 1.75 -0.15 -0.10 7/28/2004 9:00 1.6 1.9 1.95 2.2 -0.30 -0.25 7/28/2004 12:00 1.1 1.6 1.9 2.25 -0.50 -0.35 7/28/2004 14:00 0.85 1.1 1.95 2.15 -0.25 -0.20 8/2/2004 9:00 1.65 2.20 2.25 2.95 -0.55 -0.70 8/2/2004 12:00 0.56 0.71 1.1 1.26 -0.15 -0.16 8/2/2004 14:00 0.12 0.21 0.37 0.59 -0.09 -0.22 8/4/2004 9:00 4.1 2.95 3.75 3.45 1.15 0.30 8/4/2004 12:00 1.3 0.68 1.48 1.05 0.62 0.43 8/4/2004 14:00 0.1 0.29 0.37 0.64 -0.19 -0.27 8/11/2004 9:00 1.4 1.82 1.85 2.4 -0.42 -0.55 8/11/2004 12:00 0.59 1.44 0.97 1.91 -0.85 -0.94 8/11/2004 14:00 0.22 0.72 0.73 1.27 -0.50 -0.54 8/16/2004 9:00 9.90 10.00 11 11.67 -0.10 -0.67 8/16/2004 12:00 5.50 7.55 7.33 9.83 -2.05 -2.50 8/16/2004 14:00 4.70 7.10 6.75 8.17 -2.40 -1.42

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129 Table D-3. Pilot-scale study compiled TTHM data and differences. Time Time TTHM TRANS TTHM OPAQ TTHM TRANS TTHM OPAQ Difference in TTHM (TRANSOPAQ) Difference in TTHM (TRANSOPAQ) M/DD/Yr hr:min mole/Lmole/Lg/L g/L mole/L g/L 6/23/2004 9:00 1.077 0.999 139.6 131.4 0.08 8.2 6/23/2004 12:00 1.26 1.007 164.1 131.7 0.25 32.4 6/23/2004 14:00 1.033 1.008 134.3 132.1 0.02 2.2 6/30/2004 9:00 1.874 1.615 233.8 201.3 0.26 32.5 6/30/2004 12:00 2.068 2.295 258.4 286 -0.23 -27.6 6/30/2004 14:00 2.026 1.895 253.7 236.6 0.13 17.1 7/7/2004 9:00 0.865 0.742 113.3 96.9 0.12 16.4 7/7/2004 12:00 0.960 1.058 126.0 138.2 -0.10 -12.2 7/7/2004 14:00 0.946 0.877 124.6 114.9 0.07 9.7 7/14/2004 9:00 0.812 0.817 111.0 111.2 0.00 -0.2 7/14/2004 12:00 0.931 0.828 127.9 113.2 0.10 14.7 7/14/2004 14:00 0.819 0 112.8 0.0 0.82 112.8 7/26/2004 9:00 0.134 0.126 17.1 16.3 0.01 0.8 7/26/2004 12:00 0.207 0.145 26.6 19.3 0.06 7.3 7/26/2004 14:00 0.348 0.312 44.1 40.2 0.04 3.9 7/28/2004 9:00 0.740 0.945 93.7 119.4 -0.20 -25.7 7/28/2004 12:00 0.550 0.759 72.8 97.5 -0.21 -24.7 7/28/2004 14:00 0.740 0.845 95.4 108.0 -0.10 -12.6 8/2/2004 9:00 0.404 0.443 52.2 57.0 -0.04 -4.8 8/2/2004 12:00 0.006 0.453 0.9 57.8 -0.45 -56.9 8/2/2004 14:00 0.313 0.454 41.3 59.0 -0.14 -17.7 8/4/2004 9:00 0.438 0.389 55.6 49.5 0.05 6.1 8/4/2004 12:00 0.724 0.427 91.9 54.6 0.30 37.3 8/4/2004 14:00 0.267 0.416 34.1 53.3 -0.15 -19.2 8/11/2004 9:00 0.41 0.369 53.1 47.5 0.04 5.6 8/11/2004 12:00 0.476 0.321 61.7 41.6 0.16 20.1 8/11/2004 14:00 0.411 0.322 53.5 41.9 0.09 11.6 8/16/2004 9:00 0.519 0.396 65.1 49.8 0.12 15.3 8/16/2004 12:00 0.742 0.47 92.3 59.1 0.27 33.2 8/16/2004 14:00 0.587 0.409 73.4 52.0 0.18 21.4

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130 Table D-4. Pilot-scale study comp iled TTHM and normalization factors. Time Time pH Normalization Factor Temperature Normalization Factor Chlorine Residual Normalization Factor Multiplication of Normalization Factors M/DD/Yr hr:min 6/23/2004 9:00 1.00 1.01 0.89 0.89 6/23/2004 12:00 1.00 1.05 0.56 0.59 6/23/2004 14:00 1.02 1.04 0.46 0.48 6/30/2004 9:00 1.02 1.03 0.95 1.01 6/30/2004 12:00 0.99 1.03 0.78 0.79 6/30/2004 14:00 1.00 1.13 0.88 0.98 7/7/2004 9:00 1.01 1.01 0.90 0.92 7/7/2004 12:00 0.99 1.06 0.88 0.93 7/7/2004 14:00 1.00 1.11 0.79 0.88 7/14/2004 9:00 1.00 1.02 1.22 1.24 7/14/2004 12:00 0.99 1.10 0.91 0.99 7/14/2004 14:00 0.99 1.13 0.75 0.84 7/26/2004 9:00 1.00 1.01 0.90 0.91 7/26/2004 12:00 1.01 1.07 0.78 0.85 7/26/2004 14:00 0.92 1.12 0.92 0.96 7/28/2004 9:00 1.02 1.01 0.91 0.93 7/28/2004 12:00 1.05 1.03 0.81 0.88 7/28/2004 14:00 0.96 1.03 0.87 0.85 8/2/2004 9:00 1.00 1.00 0.85 0.85 8/2/2004 12:00 0.98 1.07 0.88 0.92 8/2/2004 14:00 1.00 1.11 0.73 0.81 8/4/2004 9:00 1.00 1.02 1.20 1.22 8/4/2004 12:00 1.00 1.06 1.44 1.52 8/4/2004 14:00 1.02 1.04 0.55 0.58 8/11/2004 9:00 1.00 1.00 0.86 0.86 8/11/2004 12:00 1.02 1.04 0.61 0.64 8/11/2004 14:00 1.06 1.06 0.51 0.58 8/16/2004 9:00 1.00 1.00 0.99 0.99 8/16/2004 12:00 0.97 1.08 0.84 0.87 8/16/2004 14:00 0.99 1.12 0.79 0.88

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131 Table D-5. Pilot-scale study compiled normalized TTHM data and differences. Time Time TTHM' TRANS TTHM' OPAQ Difference TTHM' (TRANSOPAQ) TTHM' TRANS TTHM' OPAQ Difference TTHM' (TRANSOPAQ) M/DD/Yr hr:min mole/L mole/Lmole/L g/L g/L g/L 6/23/2004 9:00 1.077 0.891 0.186 139.6 117.2 22.4 6/23/2004 12:00 1.26 0.592 0.668 164.1 77.5 86.6 6/23/2004 14:00 1.033 0.488 0.545 134.3 64.0 70.3 6/30/2004 9:00 1.874 1.629 0.245 233.8 203.0 30.8 6/30/2004 12:00 2.068 1.824 0.244 258.4 227.3 31.1 6/30/2004 14:00 2.026 1.861 0.165 253.7 232.3 21.4 7/7/2004 9:00 0.865 0.683 0.182 113.3 89.2 24.1 7/7/2004 12:00 0.960 0.981 -0.021 126.0 128.2 -2.2 7/7/2004 14:00 0.946 0.770 0.176 124.6 100.9 23.7 7/14/2004 9:00 0.812 1.017 -0.205 111.0 138.4 -27.4 7/14/2004 12:00 0.931 0.819 0.112 127.9 112.0 15.9 7/14/2004 14:00 0.819 0.000 0.819 112.8 0.0 112.8 7/26/2004 9:00 0.134 0.114 0.019 17.1 14.8 2.3 7/26/2004 12:00 0.207 0.122 0.085 26.6 16.3 10.3 7/26/2004 14:00 0.348 0.298 0.050 44.1 38.4 5.7 7/28/2004 9:00 0.740 0.881 -0.141 93.7 111.4 -17.7 7/28/2004 12:00 0.550 0.667 -0.117 72.8 85.8 -13.0 7/28/2004 14:00 0.740 0.719 0.021 95.4 91.9 3.5 8/2/2004 9:00 0.404 0.378 0.026 52.2 48.7 3.5 8/2/2004 12:00 0.006 0.417 -0.411 0.9 53.3 -52.4 8/2/2004 14:00 0.313 0.368 -0.055 41.3 47.8 -6.5 8/4/2004 9:00 0.438 0.476 -0.038 55.6 60.5 -4.9 8/4/2004 12:00 0.724 0.650 0.074 91.9 83.2 8.7 8/4/2004 14:00 0.267 0.243 0.024 34.1 31.1 3.0 8/11/2004 9:00 0.41 0.319 0.091 53.1 41.1 12.0 8/11/2004 12:00 0.476 0.206 0.270 61.7 26.7 35.0 8/11/2004 14:00 0.411 0.185 0.226 53.5 24.1 29.4 8/16/2004 9:00 0.519 0.394 0.125 65.1 49.5 15.6 8/16/2004 12:00 0.742 0.409 0.333 92.3 51.4 40.9 8/16/2004 14:00 0.587 0.358 0.229 73.4 45.5 27.9

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132 Table D-6. Pilot-scale study compiled HAA(5) data. Time Time HAA(5) TRANS HAA(5) OPAQ HAA(5) TRANS HAA(5) OPAQ M/DD/Yr hr:min g/L g/L moles/Lmoles/L 6/23/2004 9:00 36.19 NA 0.25 NA 6/23/2004 12:00 21.98 12.43 0.15 0.08 6/23/2004 14:00 23.46 6.78 0.17 0.04 6/30/2004 9:00 13.91 20.74 0.10 0.15 6/30/2004 12:00 24.55 8.64 0.17 0.06 6/30/2004 14:00 13.60 26.58 0.10 0.19 7/7/2004 9:00 64.88 51.71 0.46 0.36 7/7/2004 12:00 4.65 56.93 0.03 0.40 7/7/2004 14:00 60.58 33.08 0.43 1.06 7/14/2004 9:00 29.32 29.09 0.26 0.26 7/14/2004 12:00 29.53 24.79 0.26 0.22 7/14/2004 14:00 NA 95.29 NA 0.87 7/26/2004 9:00 NA 0.00 NA 0.00 7/26/2004 12:00 19.96 24.18 0.14 0.17 7/26/2004 14:00 27.69 14.55 0.20 0.10 7/28/2004 9:00 29.72 18.89 0.22 0.14 7/28/2004 12:00 38.91 31.36 0.29 0.23 7/28/2004 14:00 0.00 33.59 0.00 0.25 8/2/2004 9:00 41.11 12.13 0.29 0.07 8/2/2004 12:00 86.41 9.87 0.61 0.06 8/2/2004 14:00 40.07 15.02 0.29 0.11 8/4/2004 9:00 63.95 38.42 0.44 0.26 8/4/2004 12:00 45.64 24.29 0.31 0.16 8/4/2004 14:00 6.17 20.16 0.04 0.14 8/11/2004 9:00 61.32 7.76 0.44 0.05 8/11/2004 12:00 7.81 22.41 0.05 0.16 8/11/2004 14:00 5.78 6.12 0.04 0.04 8/16/2004 9:00 31.74 115.330.22 0.81 8/16/2004 12:00 94.59 33.81 0.66 0.23 8/16/2004 14:00 85.86 79.52 0.60 0.55

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133 Table D-7. Pilot-scale study compiled normalized HAA(5) data. Time Time HAA Chlorine Residual Normalization Factor HAA Temp Normalization Factor HAA' TRANS HAA' OPAQ HAA' TRANS HAA' OPAQ M/DD/Yr hr:min OPAQ OPAQ g/L g/L moles/L moles/L 6/23/2004 9:00 0.90 1.005 36.19 NA 0.25 NA 6/23/2004 12:00 0.61 1.033 21.98 7.84 0.15 0.05 6/23/2004 14:00 0.51 1.025 23.46 3.57 0.17 0.02 6/30/2004 9:00 0.96 1.022 13.91 20.36 0.10 0.14 6/30/2004 12:00 0.81 1.018 24.55 7.13 0.17 0.05 6/30/2004 14:00 0.89 1.081 13.6 25.65 0.10 0.18 7/7/2004 9:00 0.92 1.005 64.88 47.69 0.46 0.33 7/7/2004 12:00 0.90 1.040 4.65 53.17 0.03 0.37 7/7/2004 14:00 0.82 1.070 60.58 29.06 0.43 0.93 7/14/2004 9:00 1.19 1.012 29.32 34.91 0.26 0.31 7/14/2004 12:00 0.92 1.062 29.53 24.28 0.26 0.21 7/14/2004 14:00 0.78 1.081 NA 80.30 NA 0.74 7/26/2004 9:00 0.92 1.005 NA 0.00 NA 0.00 7/26/2004 12:00 0.80 1.047 19.96 20.38 0.14 0.15 7/26/2004 14:00 0.93 1.079 27.68914.63 0.20 0.10 7/28/2004 9:00 0.92 1.007 29.72 17.52 0.22 0.13 7/28/2004 12:00 0.84 1.022 38.91 26.78 0.29 0.20 7/28/2004 14:00 0.88 1.018 0 30.22 0.00 0.22 8/2/2004 9:00 0.87 1.002 41.11410.59 0.29 0.06 8/2/2004 12:00 0.89 1.045 86.41 9.20 0.61 0.06 8/2/2004 14:00 0.76 1.070 40.07 12.29 0.29 0.09 8/4/2004 9:00 1.17 1.012 63.95 45.53 0.44 0.31 8/4/2004 12:00 1.36 1.040 45.64 34.49 0.31 0.23 8/4/2004 14:00 0.60 1.029 6.17 12.44 0.04 0.08 8/11/2004 9:00 0.88 1.000 61.32 6.84 0.44 0.04 8/11/2004 12:00 0.65 1.023 7.81 14.95 0.05 0.10 8/11/2004 14:00 0.57 1.039 5.78 3.60 0.04 0.02 8/16/2004 9:00 1.00 1.002 31.74 115.06 0.22 0.80 8/16/2004 12:00 0.86 1.049 94.59 30.46 0.66 0.21 8/16/2004 14:00 0.82 1.076 85.86 70.19 0.60 0.49

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134 Table D-8. Pilot-scale study compiled differences in HAA(5) and HAA(5) data. Time Time Difference HAA' TRANSOPAQ Difference in HAA (TRANSOPAQ) Difference in HAA (TRANSOPAQ) Difference in HAA' (TRANSOPAQ) M/DD/Yr hr:min g/L g/L moles/Lmoles/L 6/23/2004 9:00 NA NA NA NA 6/23/2004 12:00 14.1 9.55 0.07 0.10 6/23/2004 14:00 19.9 16.68 0.13 0.14 6/30/2004 9:00 -6.4 -6.83 -0.05 -0.05 6/30/2004 12:00 17.4 15.91 0.12 0.13 6/30/2004 14:00 -12.0 -12.98 -0.09 -0.09 7/7/2004 9:00 17.2 13.17 0.10 0.13 7/7/2004 12:00 -48.5 -52.28 -0.37 -0.35 7/7/2004 14:00 31.5 27.5 -0.63 -0.50 7/14/2004 9:00 -5.6 0.23 0.00 -0.05 7/14/2004 12:00 5.3 4.74 0.04 0.05 7/14/2004 14:00 NA NA NA NA 7/26/2004 9:00 NA NA NA NA 7/26/2004 12:00 -0.4 -4.22 -0.03 0.00 7/26/2004 14:00 13.1 13.139 0.10 0.10 7/28/2004 9:00 12.2 10.83 0.08 0.09 7/28/2004 12:00 12.1 7.55 0.06 0.09 7/28/2004 14:00 -30.2 -33.59 -0.25 -0.22 8/2/2004 9:00 30.5 28.98 0.21 0.22 8/2/2004 12:00 77.2 76.54 0.55 0.55 8/2/2004 14:00 27.8 25.046 0.18 0.20 8/4/2004 9:00 18.4 25.53 0.18 0.13 8/4/2004 12:00 11.2 21.35 0.15 0.08 8/4/2004 14:00 -6.3 -13.99 -0.10 -0.05 8/11/2004 9:00 54.5 53.56 0.39 0.39 8/11/2004 12:00 -7.1 -14.6 -0.11 -0.06 8/11/2004 14:00 2.2 -0.34 0.00 0.01 8/16/2004 9:00 -83.3 -83.59 -0.59 -0.59 8/16/2004 12:00 64.1 60.78 0.43 0.45 8/16/2004 14:00 15.7 6.34 0.05 0.11

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135 Table D-9. Full-scale study compile d and calculated parameter data. Time Time pH UNCOV pH COV UNCOV Temperature COV Temperature Difference in Temperature (UNCOVCOV) M/DD/Yr hr:min (C) (C) (C) 8/19/2004 9:00 6.8 6.7 28.2 28.3 -0.1 8/19/2004 12:00 6.6 6.6 29.3 29.6 -0.3 8/19/2004 14:00 6.6 6.6 30.1 29.6 0.5 8/24/2004 9:00 6.90 6.90 28.0 27.8 0.2 8/24/2004 12:00 6.92 6.87 28.9 29.0 -0.1 8/24/2004 14:00 6.87 6.87 29.7 29.6 0.1 8/25/2004 9:00 6.72 6.51 28.5 28.1 0.4 8/25/2004 12:00 6.80 6.85 29.9 29.2 0.7 8/25/2004 14:00 6.89 6.95 29.7 28.8 0.9 Table D-10. Full-scale study compiled chlorine data and differences. Time Time Free Cl2 Residual UNCOV Free Cl2Residual COV Free Cl2 Residual (UNCOVCOV) Total Cl2 Residual UNCOV Total Cl2 Residual COV Total Cl2 Residual (UNCOVCOV) M/DD/Yr hr:min mg/L mg/L mg/L mg/L mg/L mg/L 8/19/2004 9:00 2.45 2.75 -0.30 3.3 3.8 -0.50 8/19/2004 12:00 1.90 2.75 -0.85 3.15 3.8 -0.65 8/19/2004 14:00 2.90 3.55 -0.65 3.9 4.5 -0.60 8/24/2004 9:00 1.5 2.55 -1.05 3.35 3.45 -0.10 8/24/2004 12:00 2.4 2.85 -0.45 3.35 3.85 -0.50 8/24/2004 14:00 2.75 3.55 -0.80 3.4 4.25 -0.85 8/25/2004 9:00 1.50 2.55 -1.05 3.35 3.45 -0.10 8/25/2004 12:00 2.40 2.85 -0.45 3.35 3.85 -0.50 8/25/2004 14:00 2.75 3.55 -0.80 3.4 4.25 -0.85

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136 Table D-11. Full-scale study comp iled TTHM data and differences. Time Time TTHM UNCOV TTHM COV TTHM UNCOV TTHM COV Difference in TTHM (TRANSOPAQ) Difference TTHM (UNCOVCOV) M/DD/Yr hr:min mole/L mole/L g/L g/L mole/L g/L 8/19/2004 9:00 0.291 0.370 37 47 -0.08 -10 8/19/2004 12:00 0.542 0.597 68.6 75.4 -0.06 -6.8 8/19/2004 14:00 0.485 0.465 60.8 58.8 0.02 2 8/24/2004 9:00 0.655 0.768 80.5 94.2 -0.11 -13.7 8/24/2004 12:00 0.910 0.779 111.7 95.3 0.13 16.4 8/24/2004 14:00 0.867 0.916 106.1 112 -0.05 -5.9 8/25/2004 9:00 0.350 0.345 43.8 43.1 0.01 0.7 8/25/2004 12:00 0.410 0.361 51.3 45.1 0.05 6.2 8/25/2004 14:00 0.297 0.374 37.6 46.7 -0.08 -9.1 Table D-12. Full-scale study compile d TTHM and normalization factors. Time Time pH Normalization Factor Temperature Normalization Factor Chlorine Residual Normalization Factor Multiplication of Normalization Factors M/DD/Yr hr:min COV COV COV COV 8/19/2004 9:00 1.02 1.00 0.94 0.95 8/19/2004 12:00 1.00 0.99 0.81 0.80 8/19/2004 14:00 1.00 1.02 0.89 0.91 8/24/2004 9:00 1.00 1.01 0.74 0.75 8/24/2004 12:00 1.01 1.00 0.91 0.91 8/24/2004 14:00 1.00 1.00 0.87 0.87 8/25/2004 9:00 1.04 1.01 0.74 0.78 8/25/2004 12:00 0.99 1.02 0.91 0.92 8/25/2004 14:00 0.99 1.03 0.87 0.89

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137 Table D-13. Full-scale study compiled nor malized TTHM data and differences. Time Time TTHM' UNCOV TTHM' COV TTHM' UNCOV TTHM' COV Difference TTHM' (UNCOVCOV) Difference TTHM' (UNCOVCOV) M/DD/Yr hr:min mole/Lmole/Lg/L g/L mole/L g/L 8/19/2004 9:00 0.291 0.352 37 44.65 -0.061 -7.65 8/19/2004 12:00 0.542 0.480 68.6 60.64 0.062 7.96 8/19/2004 14:00 0.485 0.422 60.8 53.40 0.063 7.40 8/24/2004 9:00 0.655 0.575 80.5 70.46 0.081 10.04 8/24/2004 12:00 0.910 0.711 111.7 86.97 0.200 24.73 8/24/2004 14:00 0.867 0.796 106.1 97.39 0.071 8.71 8/25/2004 9:00 0.350 0.269 43.8 33.69 0.081 10.11 8/25/2004 12:00 0.410 0.333 51.3 41.60 0.077 9.70 8/25/2004 14:00 0.297 0.331 37.6 41.34 -0.034 -3.74 Table D-14. Full-scale study compiled HAA(5) data. Time Time HAA(5) UNCOV HAA(5) COV HAA(5) UNCOV HAA(5) COV HAA Temp Normalization Factor HAA Chlorine Residual Normalization Factor M/DD/Yr hr:min g/L g/L moles/Lmoles/L COV COV 8/19/2004 9:00 96.00 98.67 0.61 0.64 0.998 0.946 8/19/2004 12:00 118.67 105.330.77 0.68 0.993 0.837 8/19/2004 14:00 122.67 18.67 0.81 0.11 1.011 0.907 8/24/2004 9:00 109.33 89.33 0.71 0.64 1.005 0.775 8/24/2004 12:00 122.67 122.670.81 0.81 0.998 0.921 8/24/2004 14:00 136.00 125.330.90 0.83 1.002 0.885 8/25/2004 9:00 NA 101.33NA 0.73 1.009 0.775 8/25/2004 12:00 142.67 130.670.94 0.94 1.016 0.921 8/25/2004 14:00 176.00 109.331.16 0.79 1.021 0.885

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138 Table D-15. Pilot-scale study compiled normalized HAA(5) data. Time Time HAA' UNCOV HAA' COV HAA' UNCOV HAA' COV M/DD/Yr Hr:min g/L g/L moles/L moles/L 8/19/2004 9:00 96.00 93.13 0.61 0.60 8/19/2004 12:00 118.67 87.61 0.77 0.57 8/19/2004 14:00 122.67 17.13 0.81 0.10 8/24/2004 9:00 109.33 69.58 0.71 0.50 8/24/2004 12:00 122.67 112.70 0.81 0.74 8/24/2004 14:00 136.00 111.12 0.90 0.73 8/25/2004 9:00 NA 79.29 NA 0.57 8/25/2004 12:00 142.67 122.23 0.94 0.88 8/25/2004 14:00 176.00 98.72 1.16 0.71 Table D-16. Full-scale study compiled di fferences in HAA(5) and HAA(5) data. Time Time Difference HAA' UNCOVCOV Difference HAA UNCOVCOV Difference HAA UNCOVCOV Difference HAA' UNCOVCOV M/DD/Yr hr:min g/L g/L mole/L mole/L 8/19/2004 9:00 3 3 -0.03 0.01 8/19/2004 12:00 31 32 0.09 0.21 8/19/2004 14:00 106 106 0.70 0.71 8/24/2004 9:00 40 40 0.07 0.21 8/24/2004 12:00 10 10 0.00 0.07 8/24/2004 14:00 25 26 0.08 0.17 8/25/2004 9:00 na na NA NA 8/25/2004 12:00 20 21 0.00 0.06 8/25/2004 14:00 77 78 0.38 0.45

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139 APPENDIX E PILOT-SCALE DATA 5INT: Pilot Basin Feed Water, prior to chlorination 5TRU: TRANS Basin Effluent, exposed to UV radiation 5TRC: OPAQ Basin Effluent, not exposed to UV radiation Table E-1. Trihalomethane mass con centrations in the pilot-scale study. Trihalomethane (g/L) Date Time Location Chloroform BromodichloroMethane Dibromochloromethane Bromoform Total THM 6/23/20049:00 5TRU 102.931.250.5139.60 6/23/20049:00 5TRC 91.133.46.30.6131.40 6/23/200412:00 5TRU 118.239.16.30.5164.10 6/23/200412:00 5TRC 93.4325.80.5131.70 6/23/200414:00 5TRU 97.7315.10.5134.30 6/23/200414:00 5TRC 92.932.760.5132.10 6/23/2004Blank1 Blank 1 1.31.31.42.56.50 6/30/20049:00 5TRU 201.2266.20.4233.80 6/30/20049:00 5TRC 174.321.35.30.4201.30 6/30/200412:00 5TRU 221.130.16.80.4258.40 6/30/200412:00 5TRC 246.832.26.60.4286.00 6/30/200414:00 5TRU 215.530.96.90.4253.70 6/30/200414:00 5TRC 203.226.96.10.4236.60 6/30/2004Blank1 Blank 1 1.30.50.60.42.80 7/7/20049:00 5TRU 80.7266.20.4113.30 7/7/20049:00 5TRC 69.921.35.30.496.90 7/7/200412:00 5TRU 88.730.16.80.4126.00 7/7/200412:00 5TRC 9932.26.60.4138.20 7/7/200414:00 5TRU 86.430.96.90.4124.60 7/7/200414:00 5TRC 81.526.96.10.4114.90 7/7/2004Blank1 Blank 1 0.50.50.60.92.50 7/14/20049:00 5TRU 64.438.18.5 N D (5.0) 111.00 7/14/20049:00 5TRC 65.837.28.2 N D (5.0) 111.20 7/14/200412:00 5TRU 72.844.310.8 N D (5.0) 127.90 7/14/200412:00 5TRC 65.738.59 N D (5.0) 113.20

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140 Table E-1. Continued. Trihalomethane (g/L) Date Time Location Chloroform BromodichloroMethane Dibromochloromethane Bromoform Total THM 7/14/200414:00 5TRU 63.339.510 N D (5.0) 112.80 7/14/200414:00 5TRC N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.00 7/14/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.00 7/26/20049:00 5TRU 13.33.20.5 0.117.10 7/26/20049:00 5TRC 123.70.5 0.116.30 7/26/200412:00 5TRU 20.45.20.9 0.126.60 7/26/200412:00 5TRC 12.55.71 0.119.30 7/26/200414:00 5TRU 35.77.11.2 0.144.10 7/26/200414:00 5TRC 30.48.21.5 0.140.20 7/26/2004Blank1 Blank 1 0.40.20.2 0.10.90 7/28/20049:00 5TRU 76152.6 0.193.70 7/28/20049:00 5TRC 97.618.23.4 0.2119.40 7/28/200412:00 5TRU 49.518.84.3 0.272.80 7/28/200412:00 5TRC 74.918.34.1 0.297.50 7/28/200414:00 5TRU 72.318.94 0.295.40 7/28/200414:00 5TRC 8518.24.5 0.3108.00 7/28/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.00 8/2/20049:00 5TRU 39.1111.9 0.252.2 8/2/20049:00 5TRC 43.311.42.1 0.257.0 8/2/200412:00 5TRU 0.40.20.2 0.10.90 8/2/200412:00 5TRC 4411.32.3 0.257.80 8/2/200414:00 5TRU 28.211.11.8 0.241.30 8/2/200414:00 5TRC 43.312.92.6 0.259.00 8/2/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.00 8/4/20049:00 5TRU 44.49.71.4 0.155.60 8/4/20049:00 5TRC 39.191.3 0.149.50 8/4/200412:00 5TRU 73.416.22.2 0.191.90 8/4/200412:00 5TRC 42.410.51.6 0.154.60 8/4/200414:00 5TRU 26.86.30.9 0.134.10 8/4/200414:00 5TRC 41.210.41.6 0.153.30 8/4/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.00 8/11/20049:00 5TRU 39.311.72 0.153.10 8/11/20049:00 5TRC 35.99.81.7 0.147.50 8/11/200412:00 5TRU 45.413.92.3 0.161.70 8/11/200412:00 5TRC 30.89.11.6 0.141.60 8/11/200414:00 5TRU 38.612.62.2 0.153.50 8/11/200414:00 5TRC 30.49.71.7 0.141.90 8/11/2004Blank1 Blank 1 0.2 N D (5.0) N D (5.0) N D (5.0) 0.20 8/16/20049:00 5TRU 54.59.41.1 0.165.10

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141 Table E-1. Continued. Trihalomethane (g/L) Date Time Location Chloroform BromodichloroMethane Dibromochloromethane Bromoform Total THM 8/16/20049:00 5TRC 41.27.70.9049.80 8/16/200412:00 5TRU 79.511.61.2092.30 8/16/200412:00 5TRC 48.79.41.0059.10 8/16/200414:00 5TRU 61.910.31.2073.40 8/16/200414:00 5TRC 41.39.51.10.152.00 8/16/2004Blank1 Blank 1 0.2 N D (5.0) N D (5.0) N D (5.0) 0.2

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142 Table E-2. Trihalomethane molar con centrations in the pilot-scale study. Trihalomethane (moles/L) Date Time Location Chloroform BromodichloroMethane Dibromochloromethane Bromoform Total THM 6/23/20049:00 5TRU 0.8610.1900.0240.0021.077 6/23/20049:00 5TRC 0.7620.2040.0300.0020.999 6/23/200412:00 5TRU 0.9890.2380.0300.0021.260 6/23/200412:00 5TRC 0.7820.1950.0280.0021.007 6/23/200414:00 5TRU 0.8180.1890.0240.0021.033 6/23/200414:00 5TRC 0.7770.1990.0290.0021.008 6/23/2004Blank1 Blank 1 0.0110.0080.0070.0100.035 6/30/20049:00 5TRU 1.6840.1590.0300.0021.874 6/30/20049:00 5TRC 1.4590.1300.0250.0021.615 6/30/200412:00 5TRU 1.8500.1840.0330.0022.068 6/30/200412:00 5TRC 2.0650.1960.0320.0022.295 6/30/200414:00 5TRU 1.8030.1880.0330.0022.026 6/30/200414:00 5TRC 1.7000.1640.0290.0021.895 6/30/2004Blank1 Blank 1 0.0110.0030.0030.0020.018 7/7/20049:00 5TRU 0.6750.1590.0300.0020.865 7/7/20049:00 5TRC 0.5850.1300.0250.0020.742 7/7/200412:00 5TRU 0.7420.1840.0330.0020.960 7/7/200412:00 5TRC 0.8280.1960.0320.0021.058 7/7/200414:00 5TRU 0.7230.1880.0330.0020.946 7/7/200414:00 5TRC 0.6820.1640.0290.0020.877 7/7/2004Blank1 Blank 1 0.0040.0030.0030.0040.014 7/14/20049:00 5TRU 0.5390.2320.041 N D (5.0) 0.812 7/14/20049:00 5TRC 0.5510.2270.039 N D (5.0) 0.817 7/14/200412:00 5TRU 0.6090.2700.052 N D (5.0) 0.931 7/14/200412:00 5TRC 0.5500.2350.043 N D (5.0) 0.828 7/14/200414:00 5TRU 0.5300.2410.048 N D (5.0) 0.819 7/14/200414:00 5TRC N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000 7/14/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000 7/26/20049:00 5TRU 0.1110.0200.0020.00040.134 7/26/20049:00 5TRC 0.1000.0230.0020.00040.126 7/26/200412:00 5TRU 0.1710.0320.0040.00040.207 7/26/200412:00 5TRC 0.1050.0350.0050.00040.145 7/26/200414:00 5TRU 0.2990.0430.0060.00040.348 7/26/200414:00 5TRC 0.2540.0500.0070.00040.312 7/26/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000 7/28/20049:00 5TRU 0.6360.0910.0120.0000.740 7/28/20049:00 5TRC 0.8170.1110.0160.0010.945 7/28/200412:00 5TRU 0.4140.1150.0210.0010.550 7/28/200412:00 5TRC 0.6270.1120.0200.0010.759

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143 Table E-2. Continued. Trihalomethane (moles/L) Date Time Location Chloroform BromodichloroMethane Dibromochloromethane Bromoform Total THM 7/28/200414:00 5TRU 0.6050.1150.019 0.0010.740 7/28/200414:00 5TRC 0.7110.1110.022 0.0010.845 7/28/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000 8/2/20049:00 5TRU 0.3270.0670.009 0.0010.404 8/2/20049:00 5TRC 0.3620.0700.010 0.0010.443 8/2/200412:00 5TRU 0.0030.0010.001 0.0000.006 8/2/200412:00 5TRC 0.3620.0790.011 0.0010.453 8/2/200414:00 5TRU 0.2360.0680.009 0.0010.313 8/2/200414:00 5TRC 0.3620.0790.012 0.0010.454 8/2/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000 8/4/20049:00 5TRU 0.3720.0590.007 0.00040.438 8/4/20049:00 5TRC 0.3270.0550.006 0.00040.389 8/4/200412:00 5TRU 0.6140.0990.011 0.00040.724 8/4/200412:00 5TRC 0.3550.0640.008 0.00040.427 8/4/200414:00 5TRU 0.2240.0380.004 0.00040.267 8/4/200414:00 5TRC 0.3450.0630.008 0.00040.416 8/4/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000 8/11/20049:00 5TRU 0.3290.0710.010 0.00040.410 8/11/20049:00 5TRC 0.3000.0600.008 0.00040.369 8/11/200412:00 5TRU 0.3800.0850.011 0.00040.476 8/11/200412:00 5TRC 0.2580.0550.008 0.00040.321 8/11/200414:00 5TRU 0.3230.0770.011 0.00040.411 8/11/200414:00 5TRC 0.2540.0590.008 0.00040.322 8/11/2004Blank1 Blank 1 0.002 N D (5.0) N D (5.0) N D (5.0) 0.002 8/16/20049:00 5TRU 0.4560.0570.005 0.00040.519 8/16/20049:00 5TRC 0.3450.0470.004 00.396 8/16/200412:00 5TRU 0.6650.0710.006 00.742 8/16/200412:00 5TRC 0.4080.0570.005 00.470 8/16/200414:00 5TRU 0.5180.0630.006 00.587 8/16/200414:00 5TRC 0.3460.0580.005 0.00040.409 8/16/2004Blank1 Blank 1 0.002 N D (5.0) N D (5.0) N D (5.0) 0.002

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144 Table E-3. Haloacetic acid mass concentrations in the pilot-scale study. Haloacetic Acid (g/L) Date Time Location MCAA MBAADCAA DBAA TCAA Total HAA 6/23/20049:00 5TRU N D(13.30) N D(4.0)18.86 N D(2.7) 17.3336.19 6/23/20049:00 5TRC N A N A N A N A N A 0 6/23/200412:00 5TRU N D(13.30) N D(4.0)11.14 N D(2.7) 10.8421.98 6/23/200412:00 5TRC N D(13.30) N D(4.0)4 N D(2.7) 8.4312.43 6/23/200414:00 5TRU N D(13.30) N D(4.0)13.91 N D(2.7) 9.5523.46 6/23/200414:00 5TRC N D(13.30) N D(4.0) N D(6.7) N D(2.7) 6.786.78 6/23/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0 6/30/20049:00 5TRU N D(13.30) N D(4.0)6.77 N D(2.7) 7.1413.91 6/30/20049:00 5TRC N D(13.30) N D(4.0)11.24 N D(2.7) 9.520.74 6/30/200412:00 5TRU N D(13.30) N D(4.0)14.22 N D(2.7) 10.3324.55 6/30/200412:00 5TRC N D(13.30) N D(4.0)2.61 N D(2.7) 6.038.64 6/30/200414:00 5TRU N D(13.30) N D(4.0)7.09 N D(2.7) 6.5113.6 6/30/200414:00 5TRC N D(13.30) N D(4.0)14.9 N D(2.7) 11.6826.58 6/30/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0 7/7/20049:00 5TRU N D(13.30) N D(4.0)37.76 N D(2.7) 27.1264.88 7/7/20049:00 5TRC N D(13.30) N D(4.0)27.21 N D(2.7) 24.551.71 7/7/200412:00 5TRU N D(13.30) N D(4.0) N D(6.7) N D(2.7) 4.654.65 7/7/200412:00 5TRC N D(13.30) N D(4.0)32.37 N D(2.7) 24.5656.93 7/7/200414:00 5TRU N D(13.30) N D(4.0)35.24 N D(2.7) 25.3460.58 7/7/200414:00 5TRC N D(13.30) N D(4.0)21.96 N D(2.7) 11.1233.08 7/7/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0 7/14/20049:00 5TRU N D(13.30) N D(4.0)17.42 N D(2.7) 11.929.32 7/14/20049:00 5TRC N D(13.30) N D(4.0)17.92 N D(2.7) 11.1729.09 7/14/200412:00 5TRU N D(13.30) N D(4.0)17.87 N D(2.7) 11.6629.53 7/14/200412:00 5TRC N D(13.30) N D(4.0)14.76 N D(2.7) 10.0324.79 7/14/200414:00 5TRU N A N A N A N A N A N A 7/14/200414:00 5TRC N D(13.30) N D(4.0)65.19 N D(2.7) 30.195.29 7/14/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0 7/26/20049:00 5TRU N A N A N A N A N A N A 7/26/20049:00 5TRC N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0 7/26/200412:00 5TRU N D(13.30) N D(4.0)13.76 N D(2.7) 6.219.96 7/26/200412:00 5TRC N D(13.30) N D(4.0)15.88 N D(2.7) 8.324.18 7/26/200414:00 5TRU N D(13.30) N D(4.0)18.62 N D(2.7) 9.06927.689 7/26/200414:00 5TRC N D(13.30) N D(4.0)8.12 N D(2.7) 6.4314.55 7/26/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0 7/28/20049:00 5TRU N D(13.30) N D(4.0)23.7 N D(2.7) 6.0229.72 7/28/20049:00 5TRC N D(13.30) N D(4.0)13.49 N D(2.7) 5.418.89 7/28/200412:00 5TRU N D(13.30) N D(4.0)29.44 N D(2.7) 9.4738.91 7/28/200412:00 5TRC N D(13.30) N D(4.0)23.13 N D(2.7) 8.2331.36

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145 Table E-3. Continued. 7/28/200414:005TRU N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0.00 7/28/200414:005TRC N D(13.30) N D(4.0)25.14 N D(2.7) 8.4533.59 7/28/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0.00 8/2/20049:005TRU N D(13.30) N D(4.0)21.17 N D(2.7) 19.9441.11 8/2/20049:005TRC N D(13.30) N D(4.0) N D(6.7) N D(2.7) 12.1312.13 8/2/200412:005TRU N D(13.30) N D(4.0)47.99 N D(2.7) 38.4286.41 8/2/200412:005TRC N D(13.30) N D(4.0) N D(6.7) N D(2.7) 9.879.87 8/2/200414:005TRU N D(13.30) N D(4.0)26.13 N D(2.7) 13.9440.07 8/2/200414:005TRC N D(13.30) N D(4.0)10.59 N D(2.7) 4.4315.02 8/2/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0.00 8/4/20049:005TRU N D(13.30) N D(4.0)30.58 N D(2.7) 33.3763.95 8/4/20049:005TRC N D(13.30) N D(4.0)17.52 N D(2.7) 20.938.42 8/4/200412:005TRU N D(13.30) N D(4.0)21.56 N D(2.7) 24.0845.64 8/4/200412:005TRC N D(13.30) N D(4.0)9.97 N D(2.7) 14.3224.29 8/4/200414:005TRU N D(13.30) N D(4.0) N D(6.7) N D(2.7) 6.176.17 8/4/200414:005TRC N D(13.30) N D(4.0)7.95 N D(2.7) 12.2120.16 8/4/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0.00 8/11/20049:005TRU N D(13.30) N D(4.0)37 N D(2.7) 24.3261.32 8/11/20049:005TRC N D(13.30) N D(4.0) N D(6.7) N D(2.7) 7.767.76 8/11/200412:005TRU N D(13.30) N D(4.0) N D(6.7) N D(2.7) 7.817.81 8/11/200412:005TRC N D(13.30) N D(4.0)11.35 N D(2.7) 11.0622.41 8/11/200414:005TRU N D(13.30) N D(4.0) N D(6.7) N D(2.7) 5.785.78 8/11/200414:005TRC N D(13.30) N D(4.0) N D(6.7) N D(2.7) 6.126.12 8/11/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0.00 8/16/20049:005TRU N D(13.30) N D(4.0)12.99 N D(2.7) 18.7531.74 8/16/20049:005TRC N D(13.30) N D(4.0)60.95 N D(2.7) 54.38115.33 8/16/200412:005TRU N D(13.30) N D(4.0)49.58 N D(2.7) 45.0194.59 8/16/200412:005TRC N D(13.30) N D(4.0)14.22 N D(2.7) 19.5933.81 8/16/200414:005TRU N D(13.30) N D(4.0)44.55 N D(2.7) 41.3185.86 8/16/200414:005TRC N D(13.30) N D(4.0)39.18 N D(2.7) 40.3479.52 8/16/2004Blank Blank N D(13.30) N D(4.0) N D(6.7) N D(2.7) N D(2.7) 0.00 Haloacetic Acid (g/L) Date Time Location MCAA MBAA DCAA DBAA TCAA Total HAA

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146 Table E-4. Haloacetic acid molar concentrations in the pilot-scale study. Haloacetic Acid (mole/L) Date Time Location MCAA MBAA DCAA DBAA TCAA Total HAA 6/23/2004 9:005TRU N D(5.0) N D(0.33)0.146202 N D(0.08) 0.1060.252 6/23/2004 9:005TRC N A N A N A N A N A 0.000 6/23/2004 12:005TRU N D(5.0) N D(0.33)0.086357 N D(0.08) 0.06630.153 6/23/2004 12:005TRC N D(5.0) N D(0.33)0.031008 N D(0.08) 0.05160.083 6/23/2004 14:005TRU N D(5.0) N D(0.33)0.107829 N D(0.08) 0.05840.166 6/23/2004 14:005TRC N D(5.0) N D(0.33) N D(0.25) N D(0.08) 0.04150.041 6/23/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83)0.000 6/30/2004 9:005TRU N D(5.0) N D(0.33)0.052 N D(0.08) 0.0440.096 6/30/2004 9:005TRC N D(5.0) N D(0.33)0.087 N D(0.08) 0.0580.145 6/30/2004 12:005TRU N D(5.0) N D(0.33)0.110 N D(0.08) 0.0630.173 6/30/2004 12:005TRC N D(5.0) N D(0.33)0.020 N D(0.08) 0.0370.057 6/30/2004 14:005TRU N D(5.0) N D(0.33)0.055 N D(0.08) 0.0400.095 6/30/2004 14:005TRC N D(5.0) N D(0.33)0.116 N D(0.08) 0.0710.187 6/30/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83)0.000 7/7/2004 9:005TRU N D(5.0) N D(0.33)0.052 N D(0.08) 0.0440.096 7/7/2004 9:005TRC N D(5.0) N D(0.33)0.087 N D(0.08) 0.0580.145 7/7/2004 12:005TRU N D(5.0) N D(0.33)0.110 N D(0.08) 0.0630.173 7/7/2004 12:005TRC N D(5.0) N D(0.33)0.020 N D(0.08) 0.0370.057 7/7/2004 14:005TRU N D(5.0) N D(0.33)0.055 N D(0.08) 0.0400.095 7/7/2004 14:005TRC N D(5.0) N D(0.33)0.116 N D(0.08) 0.0710.187 7/7/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83)0.000 7/14/2004 9:005TRU N D(5.0) N D(0.33)0.135 N D(0.08) 0.07280.208 7/14/2004 9:005TRC N D(5.0) N D(0.33)0.139 N D(0.08) 0.06830.207 7/14/2004 12:005TRU N D(5.0) N D(0.33)0.139 N D(0.08) 0.07130.210 7/14/2004 12:005TRC N D(5.0) N D(0.33)0.114 N D(0.08) 0.06130.176 7/14/2004 14:005TRU N D(5.0) N A N A N A N A N A 7/14/2004 14:005TRC N D(5.0) N D(0.33)0.505 N D(0.08) 0.18410.689 7/14/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83)0.000 7/26/2004 9:005TRU N A N A N A N A N A N A 7/26/2004 9:005TRC N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83)0.000 7/26/2004 12:005TRU N D(5.0) N D(0.33)0.107 N D(0.08) 0.03790.145 7/26/2004 12:005TRC N D(5.0) N D(0.33)0.123 N D(0.08) 0.05080.174 7/26/2004 14:005TRU N D(5.0) N D(0.33)0.144 N D(0.08) 0.05550.200 7/26/2004 14:005TRC N D(5.0) N D(0.33)0.063 N D(0.08) 0.03930.102 7/26/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83)0.000 7/28/2004 9:005TRU N D(5.0) N D(0.33)0.184 N D(0.08) 0.03680.221 7/28/2004 9:005TRC N D(5.0) N D(0.33)0.105 N D(0.08) 0.0330.138 7/28/2004 12:005TRU N D(5.0) N D(0.33)0.228 N D(0.08) 0.05790.286 7/28/2004 12:005TRC N D(5.0) N D(0.33)0.179 N D(0.08) 0.05030.230 7/28/2004 14:005TRU N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83)0.000

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147 Table E-4. Continued. Haloacetic Acid (mole/L) Date Time Location MCAA MBAA DCAA DBAA TCAA Total HAA 7/28/2004 14:005TRC N D(5.0) N D(0.33)0.195 N D(0.08) 0.05170.247 7/28/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83) 0.000 8/2/2004 9:005TRU N D(5.0) N D(0.33)0.164 N D(0.08) 0.1220.286 8/2/2004 9:005TRC N D(5.0) N D(0.33) N D(0.25) N D(0.08) 0.07420.074 8/2/2004 12:005TRU N D(5.0) N D(0.33)0.372 N D(0.08) 0.2350.607 8/2/2004 12:005TRC N D(5.0) N D(0.33) N D(0.25) N D(0.08) 0.06040.060 8/2/2004 14:005TRU N D(5.0) N D(0.33)0.203 N D(0.08) 0.08530.288 8/2/2004 14:005TRC N D(5.0) N D(0.33)0.082093 N D(0.08) 0.02710.109 8/2/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83) 0.000 8/4/2004 9:005TRU N D(5.0) N D(0.33)0.237 N D(0.08) 0.20410.441 8/4/2004 9:005TRC N D(5.0) N D(0.33)0.136 N D(0.08) 0.12780.264 8/4/2004 12:005TRU N D(5.0) N D(0.33)0.167 N D(0.08) 0.14730.314 8/4/2004 12:005TRC N D(5.0) N D(0.33)0.077 N D(0.08) 0.08760.165 8/4/2004 14:005TRU N D(5.0) N D(0.33) N D(0.25) N D(0.08) 0.03770.038 8/4/2004 14:005TRC N D(5.0) N D(0.33)0.062 N D(0.08) 0.07470.136 8/4/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83) 0.000 8/11/2004 9:005TRU N D(5.0) N D(0.33)0.287 N D(0.08) 0.14870.436 8/11/2004 9:005TRC N D(5.0) N D(0.33) N D(0.25) N D(0.08) 0.04750.047 8/11/2004 12:005TRU N D(5.0) N D(0.33) N D(0.25) N D(0.08) 0.04780.048 8/11/2004 12:005TRC N D(5.0) N D(0.33)0.088 N D(0.08) 0.06760.156 8/11/2004 14:005TRU N D(5.0) N D(0.33) N D(0.25) N D(0.08) 0.03540.035 8/11/2004 14:005TRC N D(5.0) N D(0.33) N D(0.25) N D(0.08) 0.03740.037 8/11/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83) 0.000 8/16/2004 9:005TRU N D(5.0) N D(0.33)0.101 N D(0.08) 0.11470.215 8/16/2004 9:005TRC N D(5.0) N D(0.33)0.472 N D(0.08) 0.33260.805 8/16/2004 12:005TRU N D(5.0) N D(0.33)0.384 N D(0.08) 0.27530.660 8/16/2004 12:005TRC N D(5.0) N D(0.33)0.110 N D(0.08) 0.11980.230 8/16/2004 14:005TRU N D(5.0) N D(0.33)0.345 N D(0.08) 0.25270.598 8/16/2004 14:005TRC N D(5.0) N D(0.33)0.304 N D(0.08) 0.24670.550 8/16/2004 Blank Blank N D(5.0) N D(0.33) N D(0.25) N D(0.08) N D(0.83) 0.000

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148 Table E-5. Pilot-scale study ch lorine effluent concentrations. Date Time Location Free Cl2 (mg/L Cl2) Total Cl2 (mg/L Cl2) 6/23/20049:005TRU 1.05 3.05 6/23/20049:005TRC 1.30 3.25 6/23/200412:005INT 0.05 0.11 6/23/200412:005TRU 0.75 1.85 6/23/200412:005TRC 2.10 2.65 6/23/200414:005INT 0.09 0.20 6/23/200414:005TRU 0.25 1.40 6/23/200414:005TRC 1.00 2.10 6/30/20049:005INT 0.11 0.18 6/30/20049:005TRU 1.15 2.50 6/30/20049:005TRC 1.25 2.90 6/30/200412:005INT 0.12 0.25 6/30/200412:005TRU 1.00 2.45 6/30/2004 12:005TRC 1.55 2.80 6/30/2004 14:005INT 0.12 0.26 6/30/2004 14:005TRU 1.50 2.15 6/30/2004 14:005TRC 1.90 2.65 7/7/20049:005INT 0.09 0.13 7/7/20049:005TRU 4.10 5.20 7/7/20049:005TRC 4.90 5.75 7/7/200412:005INT 0.07 0.13 7/7/200412:005TRU 3.00 3.45 7/7/200412:005TRC 3.75 5.45 7/7/200414:005INT 0.09 0.14 7/7/200414:005TRU 2.85 3.85 7/7/200414:005TRC 4.30 5.10 7/14/20049:005INT 0.07 0.10 7/14/20049:005TRU 3.85 4.50 7/14/20049:005TRC 2.70 3.70 7/14/200412:005INT 0.12 0.23 7/14/200412:005TRU 1.90 2.80 7/14/200412:005TRC 2.25 2.35 7/14/200414:005INT 0.10 0.24 7/14/200414:005TRU 1.10 1.55 7/14/200414:005TRC 1.85 2.50 7/26/20049:005INT 0.04 0.09 7/26/20049:005TRU 0.25 2.90 7/26/20049:005TRC 0.30 3.00 7/26/200412:005INT 0.11 0.20

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149 Table E-5. Continued. Date Time Location Free Cl2 (mg/L Cl2) Total Cl2 (mg/L Cl2) 7/26/200412:005TRU 0.35 1.05 7/26/200412:005TRC 0.55 1.30 7/26/200414:005INT 0.14 0.13 7/26/200414:005TRU 0.95 1.65 7/26/200414:005TRC 1.10 1.75 7/28/20049:005INT 0.05 0.07 7/28/20049:005TRU 1.60 1.95 7/28/20049:005TRC 1.90 2.20 7/28/200412:005INT 0.10 0.17 7/28/200412:005TRU 1.10 1.90 7/28/200412:005TRC 1.60 2.25 7/28/200414:005INT 0.05 0.11 7/28/200414:005TRU 0.85 1.95 7/28/200414:005TRC 1.10 2.15 8/2/20049:005INT 0.04 0.09 8/2/20049:005TRU 1.65 2.25 8/2/20049:005TRC 2.20 2.95 8/2/200412:005INT 0.11 0.27 8/2/200412:005TRU 0.56 1.1 8/2/200412:005TRC 0.71 1.26 8/2/200414:005INT 0.12 0.19 8/2/200414:005TRU 0.12 0.37 8/2/200414:005TRC 0.21 0.59 8/4/20049:005INT 0.11 0.17 8/4/20049:005TRU 4.10 3.75 8/4/20049:005TRC 2.95 3.45 8/4/200412:005INT 0.10 0.23 8/4/200412:005TRU 1.30 1.48 8/4/200412:005TRC 0.68 1.05 8/4/200414:005INT 0.21 0.26 8/4/200414:005TRU 0.10 0.37 8/4/200414:005TRC 0.29 0.64 8/11/20049:005INT 0.04 0.09 8/11/20049:005TRU 1.40 1.85 8/11/20049:005TRC 1.82 2.4 8/11/200412:005INT 0.07 0.14 8/11/200412:005TRU 0.59 0.97 8/11/200412:005TRC 1.44 1.91 8/11/200414:005INT 0.14 0.25 8/11/200414:005TRU 0.22 0.73 8/11/200414:005TRC 0.72 1.27

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150 Table E-5. Continued. Date Time Location Free Cl2 (mg/L Cl2) Total Cl2 (mg/L Cl2) 8/16/20049:005INT 0.07 0.10 8/16/20049:005TRU 9.90 11.00 8/16/20049:005TRC 10.00 11.67 8/16/200412:005INT 0.13 0.20 8/16/200412:005TRU 5.50 7.33 8/16/200412:005TRC 7.55 9.83 8/16/200414:005INT 0.06 0.16 8/16/200414:005TRU 4.70 6.75 8/16/200414:005TRC 7.10 8.17

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151 Table E-6. Pilot-scale probe parameter data. Date Time Location pH Temperature (C) Conductivity (mhos/cm) Dissolved Oxygen (mg/L O2) 6/23/20049:005INT 6.88 27.4 702 NA 6/23/20049:005TRU 6.85 27.2 745 NA 6/23/20049:005TRC 6.86 27.0 740 NA 6/23/200412:005INT 6.89 27.6 733 NA 6/23/200412:005TRU 6.83 29.0 768 NA 6/23/200412:005TRC 6.85 27.6 758 NA 6/23/200414:005INT 6.97 28.9 714 NA 6/23/200414:005TRU 6.87 30.3 742 NA 6/23/200414:005TRC 6.78 29.2 744 NA 6/30/20049:005INT 7.44 28.4 594 4.25 6/30/20049:005TRU 7.34 28.4 632 2.40 6/30/20049:005TRC 7.2 27.5 628 2.75 6/30/200412:005INT 7.38 28.8 622 2.75 6/30/200412:005TRU 7.3 30.4 646 3.25 6/30/200412:005TRC 7.37 29.6 637 3.25 6/30/200414:005INT 7.39 29.2 648 3.75 6/30/200414:005TRU 7.36 33.5 648 3.15 6/30/200414:005TRC 7.39 29.8 642 3.25 7/7/20049:005INT 7.27 29.2 624 4.30 7/7/20049:005TRU 7.29 28.3 637 2.50 7/7/20049:005TRC 7.23 28.1 640 2.50 7/7/200412:005INT 7.31 29.9 658 4.30 7/7/200412:005TRU 7.27 31.7 672 3.25 7/7/200412:005TRC 7.33 29.9 658 4.00 7/7/200414:005INT 7.4 30.1 657 3.55 7/7/200414:005TRU 7.33 33.0 765 3.10 7/7/200414:005TRC 7.35 29.8 704 2.95 7/14/20049:005INT 7.13 28.5 658 3.50 7/14/20049:005TRU 7.25 27.9 703 2.50 7/14/20049:005TRC 7.24 27.4 698 3.00 7/14/200412:005INT 7.23 30.0 749 3.95 7/14/200412:005TRU 7.22 31.2 734 3.30 7/14/200412:005TRC 7.27 28.5 719 3.05 7/14/200414:005INT 7.36 30.6 684 4.25 7/14/200414:005TRU 7.23 33.3 698 3.30 7/14/200414:005TRC 7.27 29.6 704 3.60 7/26/20049:005INT 7.04 28.3 668 1.75 7/26/20049:005TRU 6.63 28.1 704 1.30 7/26/20049:005TRC 6.64 27.9 708 1.15

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152 Table E-6. Continued. Date Time Location pH Temperature (C) Conductivity (mhos/cm) Dissolved Oxygen (mg/L O2) 7/26/200412:005INT 7.21 30.5 640 3.40 7/26/200412:005TRU 6.3 31.3 666 1.45 7/26/200412:005TRC 6.22 29.2 640 1.50 7/26/200414:005INT 7.29 31.1 673 3.40 7/26/200414:005TRU 6.07 33.5 730 2.70 7/26/200414:005TRC 6.5 29.9 751 2.40 7/28/20049:005INT 7.26 28.6 760 3.15 7/28/20049:005TRU 9.61 28.1 819 3.00 7/28/20049:005TRC 9.48 27.8 950 3.10 7/28/200412:005INT 7.31 30.0 731 4.20 7/28/200412:005TRU 9.3 31.0 813 3.25 7/28/200412:005TRC 8.92 30.0 796 3.00 7/28/200414:005INT 7.32 28.5 768 3.40 7/28/200414:005TRU 8.4 29.9 792 3.40 7/28/200414:005TRC 8.73 29.1 772 3.65 8/2/20049:005INT 7.11 28.5 513 1.45 8/2/20049:005TRU 7.2 28.1 530 2.60 8/2/20049:005TRC 7.2 28.0 534 2.90 8/2/200412:005INT 7.37 30.5 508 3.75 8/2/200412:005TRU 7.35 31.3 510 3.30 8/2/200412:005TRC 7.45 29.3 521 3.50 8/2/200414:005INT 7.58 30.4 515 4.20 8/2/200414:005TRU 7.53 33.0 529 3.10 8/2/200414:005TRC 7.53 29.8 523 3.30 8/4/20049:005INT 7.38 29.1 505 3.25 8/4/20049:005TRU 7.3 28.3 513 3.30 8/4/20049:005TRC 7.31 27.8 514 2.95 8/4/200412:005INT 7.28 30.7 499 3.65 8/4/200412:005TRU 7.08 31.2 518 3.40 8/4/200412:005TRC 7.1 29.4 511 3.20 8/4/200414:005INT 7.37 31.1 503 4.35 8/4/200414:005TRU 7.26 33.5 510 3.90 8/4/200414:005TRC 7.16 32.1 510 3.25 8/11/20049:005INT 7.18 27.7 491 3.75 8/11/20049:005TRU 7.05 27.4 502 3.05 8/11/20049:005TRC 7.04 27.4 506 2.85 8/11/200412:005INT 7.38 29.1 493 3.80 8/11/200412:005TRU 7.34 29.2 505 4.85 8/11/200412:005TRC 7.2 28.2 508 3.45 8/11/200414:005INT 7.42 30.5 486 4.25 8/11/200414:005TRU 7.59 30.6 509 6.10

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153 Table E-6. Continued. Date Time Location pH Temperature (C) Conductivity (mhos/cm) Dissolved Oxygen (mg/L O2) 8/11/200414:005TRC 7.24 28.9 489 3.80 8/16/20049:005INT 6.82 28.0 507 3.20 8/16/20049:005TRU 7.12 27.1 559 2.50 8/16/20049:005TRC 7.14 27.0 555 2.15 8/16/200412:005INT 7.26 29.7 525 3.75 8/16/200412:005TRU 7.26 30.4 564 2.00 8/16/200412:005TRC 7.48 28.3 550 2.40 8/16/200414:005INT 7.24 30.2 511 3.30 8/16/200414:005TRU 7.36 32.6 563 3.15 8/16/200414:005TRC 7.45 29.2 544 2.65

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154 Table E-7. Pilot-scale data provided by GRU laboratory. Date Time Location TSS (mg/L) Total Coliform (# /100 mL) 6/23/20049:005INT 0.9 4100 6/23/20049:005TRU 0.6 0.5 6/23/20049:005TRC 0.4 0.5 6/23/200412:005INT 1.3 6400 6/23/200412:005TRU 0.5 0.5 6/23/200412:005TRC 0.3 0.5 6/23/200414:005INT 0.4 5200 6/23/200414:005TRU 0.4 1.0 6/23/200414:005TRC 0.2 0.5 6/30/20049:005INT 0.2 5500 6/30/20049:005TRU 0.2 0.2 6/30/20049:005TRC 0.1 0.2 6/30/200412:005INT 0.3 3650 6/30/200412:005TRU 0.2 0.2 6/30/200412:005TRC 0.2 0.2 6/30/200414:005INT 0.2 4750 6/30/200414:005TRU 0.1 0.2 6/30/200414:005TRC 0.2 0.2 7/7/20049:005INT 0.4 16000 7/7/20049:005TRU 0.2 0.4 7/7/20049:005TRC 0.2 0.1 7/7/200412:005INT 0.4 16000 7/7/200412:005TRU 0.3 0.1 7/7/200412:005TRC 0.2 0.1 7/7/200414:005INT 0.4 16000 7/7/200414:005TRU 0.2 2.5 7/7/200414:005TRC 0.2 0.1 7/14/20049:005INT 3.0 7200 7/14/20049:005TRU 0.3 0.1 7/14/20049:005TRC 0.2 0.1 7/14/200412:005INT 0.6 8600 7/14/200412:005TRU 0.1 0.1 7/14/200412:005TRC 0.1 0.1 7/14/200414:005INT 0.2 5600 7/14/200414:005TRU 0.2 0.1 7/14/200414:005TRC 0.1 0.1 7/26/20049:005INT 0.6 3800 7/26/20049:005TRU 0.4 0.1 7/26/20049:005TRC 0.3 0.1 7/26/200412:005INT 1.0 5400

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155 Table E-7. Continued. Date Time Location TSS (mg/L) Total Coliform (# /100 mL) 7/26/200412:005TRU 0.4 0.1 7/26/200412:005TRC 0.2 0.1 7/26/200414:005INT 0.6 1800 7/26/200414:005TRU 0.3 0.1 7/26/200414:005TRC 0.2 0.1 7/28/20049:005INT 1.5 1600 7/28/20049:005TRU 5.7 0.1 7/28/20049:005TRC 5.4 0.2 7/28/200412:005INT 2.7 2300 7/28/200412:005TRU 0.7 0.1 7/28/200412:005TRC 1.6 0.1 7/28/200414:005INT 0.4 3200 7/28/200414:005TRU 0.5 0.1 7/28/200414:005TRC 0.5 0.1 8/2/20049:005INT 0.7 3900 8/2/20049:005TRU 0.1 0.2 8/2/20049:005TRC 0.1 0.2 8/2/200412:005INT 2.1 1900 8/2/200412:005TRU 0.1 0.2 8/2/200412:005TRC 0.1 0.2 8/2/200414:005INT 3.8 1600 8/2/200414:005TRU 0.1 0.1 8/2/200414:005TRC 0.1 0.1 8/4/20049:005INT 1.3 2800 8/4/20049:005TRU 0.1 0.1 8/4/20049:005TRC 0.1 0.4 8/4/200412:005INT 1.8 4100 8/4/200412:005TRU 0.1 0.1 8/4/200412:005TRC 0.1 0.3 8/4/200414:005INT 0.2 2700 8/4/200414:005TRU 0.2 0.1 8/4/200414:005TRC 0.1 0.3 8/11/20049:005INT 2.7 4000 8/11/20049:005TRU 0.1 0.1 8/11/20049:005TRC 0.0 0.1 8/11/200412:005INT 0.6 2700 8/11/200412:005TRU 0.6 0.1 8/11/200412:005TRC 0.2 0.1 8/11/200414:005INT 0.7 2600 8/11/200414:005TRU 0.7 0.1 8/11/200414:005TRU 0.3 0.1

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156 Table E-7. Continued. Date Time Location TSS (mg/L) Total Coliform (# /100 mL) 8/16/20049:005INT 0.3 1900 8/16/20049:005TRU 0.2 0.1 8/16/20049:005TRC 0.4 0.1 8/16/200412:005INT 3.0 2400 8/16/200412:005TRU 1.4 0.1 8/16/200412:005TRC 0.3 0.1 8/16/200414:005INT 0.5 3000 8/16/200414:005TRU 0.4 0.1 8/16/200414:005TRU 0.3 0.1

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157 APPENDIX F FULL-SCALE DATA 5PA: Post-Aeration Basin Effluent 58S: Inlet of the North Chlorine Contact Basin 53S: Uncovered Side Effluent (UNCOV) of the North Chlorine Contact Basin 53N: Covered Side Effluent (COV) of the North Chlorine Contact Basin Table F-1. Trihalomethane mass con centrations in the full-scale study. Trihalomethane (g/L) Date Time Location Chloroform BromodichloroMethane Dibromochloromethane Bromoform Total THM 8/19/2004 9:00 58S Inf 43.110.3 N D (5.0) N D (5.0) 53.4 8/19/2004 9:00 53S 28.78.3 N D (5.0) N D (5.0) 37 8/19/2004 9:00 53N 36.810.2 N D (5.0) N D (5.0) 47 8/19/200412:00 58S Inf 32.88.7 N D (5.0) N D (5.0) 41.5 8/19/200412:00 53S 54.414.2 N D (5.0) N D (5.0) 68.6 8/19/200412:00 53N 60.415 N D (5.0) N D (5.0) 75.4 8/19/200414:00 58S Inf 43.810.7 N D (5.0) N D (5.0) 54.5 8/19/200414:00 53S 50.410.4 N D (5.0) N D (5.0) 60.8 8/19/200414:00 53N 46.911.9 N D (5.0) N D (5.0) 58.8 8/19/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0 8/24/20049:00 58S1 Inf 52.6 N D (5.0) N D (5.0) N D (5.0) 52.6 8/24/20049:00 58S2 Inf 71.19.3 N D (5.0) N D (5.0) 80.4 8/24/20049:00 53S 72.48.1 N D (5.0) N D (5.0) 80.5 8/24/20049:00 53N 85.48.8 N D (5.0) N D (5.0) 94.2 8/24/200412:00 58S1 Inf 73.110 N D (5.0) N D (5.0) 83.1 8/24/200412:00 58S2 Inf 61.17.3 N D (5.0) N D (5.0) 68.4 8/24/200412:00 53S 10110.7 N D (5.0) N D (5.0) 111.7 8/24/200412:00 53N 878.3 N D (5.0) N D (5.0) 95.3 8/24/200414:00 58S1 Inf 64.28.1 N D (5.0) N D (5.0) 72.3 8/24/200414:00 58S2 Inf 75.77.8 N D (5.0) N D (5.0) 83.5 8/24/200414:00 53S 96.89.3 N D (5.0) N D (5.0) 106.1 8/24/200414:00 53N 102.59.5 N D (5.0) N D (5.0) 112 8/24/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0 8/25/20049:00 58S1 Inf 25 N D (5.0) N D (5.0) N D (5.0) 25

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158 Table F-1. Continued. Trihalomethane (g/L) Date Time Location Chloroform BromodichloroMethane Dibromochloromethane Bromoform Total THM 8/25/20049:00 58S2 Inf 24.1 N D (5.0) N D (5.0) N D (5.0) 24.1 8/25/20049:00 53S 36.67.2 N D (5.0) N D (5.0) 43.8 8/25/20049:00 53N 36.17 N D (5.0) N D (5.0) 43.1 8/25/200412:00 58S1 Inf 32.25.1 N D (5.0) N D (5.0) 37.3 8/25/200412:00 58S2 Inf 315.7 N D (5.0) N D (5.0) 36.7 8/25/200412:00 53S 438.3 N D (5.0) N D (5.0) 51.3 8/25/200412:00 53N 37.97.2 N D (5.0) N D (5.0) 45.1 8/25/200414:00 58S1 Inf 35.27 N D (5.0) N D (5.0) 42.2 8/25/200414:00 58S2 Inf 34.56.5 N D (5.0) N D (5.0) 41 8/25/200414:00 53S 307.6 N D (5.0) N D (5.0) 37.6 8/25/200414:00 53N 39.37.4 N D (5.0) N D (5.0) 46.7 8/25/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0

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159 Table F-2. Trihalomethane molar concentrations in the full-scale study. Trihalomethane (moles/L) Date Time LocationChloroform BromodichloroMethane Dibromochloromethane Bromoform Total THM 8/19/2004 9:00 58S Inf 0.3610.063 N D (5.0) N D (5.0) 0.423 8/19/2004 9:00 53S 0.2400.051 N D (5.0) N D (5.0) 0.291 8/19/2004 9:00 53N 0.3080.062 N D (5.0) N D (5.0) 0.370 8/19/200412:00 58S Inf 0.2740.053 N D (5.0) N D (5.0) 0.328 8/19/200412:00 53S 0.4550.087 N D (5.0) N D (5.0) 0.542 8/19/200412:00 53N 0.5050.091 N D (5.0) N D (5.0) 0.597 8/19/200414:00 58S Inf 0.3670.065 N D (5.0) N D (5.0) 0.432 8/19/200414:00 53S 0.4220.063 N D (5.0) N D (5.0) 0.485 8/19/200414:00 53N 0.3920.073 N D (5.0) N D (5.0) 0.465 8/19/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000 8/24/20049:00 58S1 Inf 0.440 N D (5.0) N D (5.0) N D (5.0) 0.440 8/24/20049:00 58S2 Inf 0.5950.057 N D (5.0) N D (5.0) 0.652 8/24/20049:00 53S 0.6060.049 N D (5.0) N D (5.0) 0.655 8/24/20049:00 53N 0.7150.054 N D (5.0) N D (5.0) 0.768 8/24/200412:00 58S1 Inf 0.6120.061 N D (5.0) N D (5.0) 0.673 8/24/200412:00 58S2 Inf 0.5110.045 N D (5.0) N D (5.0) 0.556 8/24/200412:00 53S 0.8450.065 N D (5.0) N D (5.0) 0.910 8/24/200412:00 53N 0.7280.051 N D (5.0) N D (5.0) 0.779 8/24/200414:00 58S1 Inf 0.5370.049 N D (5.0) N D (5.0) 0.587 8/24/200414:00 58S2 Inf 0.6330.048 N D (5.0) N D (5.0) 0.681 8/24/200414:00 53S 0.8100.057 N D (5.0) N D (5.0) 0.867 8/24/200414:00 53N 0.8580.058 N D (5.0) N D (5.0) 0.916 8/24/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000 8/25/20049:00 58S1 Inf 0.209 N D (5.0) N D (5.0) N D (5.0) 0.209 8/25/20049:00 58S2 Inf 0.202 N D (5.0) N D (5.0) N D (5.0) 0.202 8/25/20049:00 53S 0.3060.044 N D (5.0) N D (5.0) 0.350 8/25/20049:00 53N 0.3020.043 N D (5.0) N D (5.0) 0.345 8/25/200412:00 58S1 Inf 0.2690.031 N D (5.0) N D (5.0) 0.301 8/25/200412:00 58S2 Inf 0.2590.035 N D (5.0) N D (5.0) 0.294 8/25/200412:00 53S 0.3600.051 N D (5.0) N D (5.0) 0.410 8/25/200412:00 53N 0.3170.044 N D (5.0) N D (5.0) 0.361 8/25/200414:00 58S1 Inf 0.2950.043 N D (5.0) N D (5.0) 0.337 8/25/200414:00 58S2 Inf 0.2890.040 N D (5.0) N D (5.0) 0.328 8/25/200414:00 53S 0.2510.046 N D (5.0) N D (5.0) 0.297 8/25/200414:00 53N 0.3290.045 N D (5.0) N D (5.0) 0.374 8/25/2004Blank1 Blank 1 N D (5.0) N D (5.0) N D (5.0) N D (5.0) 0.000

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160 Table F-3. Haloacetic acid mass con centrations in the full-scale study. Haloacetic Acid (g/L) Date Time Location MCAA MBAA DCAA DBAA TCAA Total HAA 8/19/2004 9:0058S Inf 968.47 N D(0.33)52.14 N D(0.08) 18.91039.51 8/19/2004 9:0053S 118.04 N D(0.33)58.61 N D(0.08) 25.23201.88 8/19/2004 9:0053N 970.44 N D(0.33)60.12 N D(0.08) 27.751058.31 8/19/2004 12:0058S Inf 968.71 N D(0.33)53.92 N D(0.08) 18.461041.09 8/19/2004 12:0053S 932.87 N D(0.33)74.91 N D(0.08) 31.581039.36 8/19/2004 12:0053N 187.35 N D(0.33)66.87 N D(0.08) 26.22280.44 8/19/2004 14:0058S Inf 466.44 N D(0.33)65.99 N D(0.08) 24.71557.14 8/19/2004 14:0053S 188.45 N D(0.33)77.16 N D(0.08) 34.49300.1 8/19/2004 14:0053N 163.13 N D(0.33) N D(0.25) N D(0.08) 19.26182.39 8/19/2004 Blank1 Blank 1 N D(0.17) N D(0.33) N D(0.25) N D(0.08) N D(0.83) 0 8/24/2004 9:0058S Inf 276.13 N D(0.33)59.54 N D(0.08) 29.57365.24 8/24/2004 9:0053S 305.07 N D(0.33)64.49 N D(0.08) 34.78404.34 8/24/2004 9:0053N 365.60 N D(0.33)58.21 N D(0.08) 30.82454.63 8/24/2004 12:0058S Inf 290.32 N D(0.33)70.93 N D(0.08) 31.77393.02 8/24/2004 12:0053S 585.61 N D(0.33)76.89 N D(0.08) 34.91697.41 8/24/2004 12:0053N 464.72 N D(0.33)74.37 N D(0.08) 17.74556.83 8/24/2004 14:0058S Inf 340.13 N D(0.33)64.38 N D(0.08) 30.10434.61 8/24/2004 14:0053S 411.33 N D(0.33)84.59 N D(0.08) 41.94537.86 8/24/2004 14:0053N 470.44 N D(0.33)75.93 N D(0.08) 38.84585.21 8/24/2004 Blank1 Blank 1 N D (0.17) N D(0.33) N D(0.25) N D(0.08) N D(0.83) 0 8/25/2004 9:0058S Inf 339.40 N D(0.33)59.32 N D(0.08) 30.025428.74 8/25/2004 9:0053S N A N D(0.33) N A N D(0.08) N A 0 8/25/2004 9:0053N 526.11 N D(0.33)66.60 N D(0.08) 34.11626.82 8/25/2004 12:0058S Inf 393.74 N D(0.33)70.88 N D(0.08) 33.78498.4 8/25/2004 12:0053S 396.91 N D(0.33)83.61 N D(0.08) 47.3527.82 8/25/2004 12:0053N 289.31 N D(0.33)84.00 N D(0.08) 46.41419.72 8/25/2004 14:0058S Inf 320.71 N D(0.33)71.92 N D(0.08) 32.43425.06 8/25/2004 14:0053S 1000.00 N D(0.33)102.81 N D(0.08) 59.571162.38 8/25/2004 14:0053N 26.79 N D(0.33)72.25 N D(0.08) 36.88135.92 8/25/2004 Blank1 Blank 1 N D (0.17) N D(0.33) N D(0.25) N D(0.08) N D(0.83) 0

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161 Table F-4. Haloacetic acid molar c oncentrations in the full-scale study. Haloacetic Acid (mole/L) Date Time Location MCAA MBAA DCAA DBAA TCAA Total HAA 8/19/2004 9:0058S Inf 10.25 N D(0.33)0.40 N D(0.08) 0.1210.77 8/19/2004 9:0053S 1.25 N D(0.33)0.45 N D(0.08) 0.151.86 8/19/2004 9:0053N 10.27 N D(0.33)0.47 N D(0.08) 0.1710.91 8/19/2004 12:0058S Inf 10.25 N D(0.33)0.42 N D(0.08) 0.1110.78 8/19/2004 12:0053S 9.87 N D(0.33)0.58 N D(0.08) 0.1910.65 8/19/2004 12:0053N 1.98 N D(0.33)0.52 N D(0.08) 0.162.66 8/19/2004 14:0058S Inf 4.94 N D(0.33)0.51 N D(0.08) 0.155.60 8/19/2004 14:0053S 1.99 N D(0.33)0.60 N D(0.08) 0.212.80 8/19/2004 14:0053N 1.73 N D(0.33) N D(0.25) N D(0.08) 0.121.84 8/19/2004 Blank1 Blank 1 N A N A N A N D(0.08) N A 0.00 8/24/2004 9:0058S Inf 2.92 N D(0.33)0.46 N D(0.08) 0.183.56 8/24/2004 9:0053S 3.23 N D(0.33)0.50 N D(0.08) 0.213.94 8/24/2004 9:0053N 3.87 N D(0.33)0.45 N D(0.08) 0.194.51 8/24/2004 12:0058S Inf 3.07 N D(0.33)0.55 N D(0.08) 0.193.82 8/24/2004 12:0053S 6.20 N D(0.33)0.60 N D(0.08) 0.217.01 8/24/2004 12:0053N 4.92 N D(0.33)0.58 N D(0.08) 0.115.60 8/24/2004 14:0058S Inf 3.60 N D(0.33)0.50 N D(0.08) 0.184.28 8/24/2004 14:0053S 4.35 N D(0.33)0.66 N D(0.08) 0.265.27 8/24/2004 14:0053N 4.98 N D(0.33)0.59 N D(0.08) 0.245.80 8/24/2004 Blank1 Blank 1 N A N A N A N D(0.08) N A 0.00 8/25/2004 9:0058S Inf 3.59 N D(0.33)0.46 N D(0.08) 0.184.24 8/25/2004 9:0053S N A N D(0.33) N A N D(0.08) N A 0.00 8/25/2004 9:0053N 5.57 N D(0.33)0.52 N D(0.08) 0.216.29 8/25/2004 12:0058S Inf 4.17 N D(0.33)0.55 N D(0.08) 0.214.92 8/25/2004 12:0053S 4.20 N D(0.33)0.65 N D(0.08) 0.295.14 8/25/2004 12:0053N 3.06 N D(0.33)0.65 N D(0.08) 0.284.00 8/25/2004 14:0058S Inf 3.39 N D(0.33)0.56 N D(0.08) 0.204.15 8/25/2004 14:0053S 10.58 N D(0.33)0.80 N D(0.08) 0.3611.74 8/25/2004 14:0053N 0.28 N D(0.33)0.56 N D(0.08) 0.231.07 8/25/2004 Blank1 Blank 1 N A N A N A N D(0.08) N A 0.00

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162 Table F-5. Full-scale study chlo rine effluent concentrations. Date Time Location Free Cl2 (mg/L Cl2) Total Cl2 (mg/L Cl2) 8/19/20049:005PA 0.09 0.12 8/19/20049:0058S 3.75 4.60 8/19/20049:0053S 2.45 3.30 8/19/20049:0053N 2.75 3.80 8/19/200412:005PA 0.06 0.13 8/19/200412:0058S 3.30 4.25 8/19/200412:0053S 1.90 3.15 8/19/200412:0053N 2.75 3.80 8/19/200414:005PA 0.07 0.11 8/19/200414:0058S 4.65 5.20 8/19/200414:0053S 2.90 3.90 8/19/200414:0053N 3.55 4.50 8/24/20049:005PA 0.04 0.09 8/24/2004 9:0058S 3.05 4.45 8/24/2004 9:0053S 1.50 3.35 8/24/2004 9:0053N 2.55 3.45 8/24/2004 12:005PA 0.05 0.23 8/24/2004 12:0058S 4.05 4.70 8/24/2004 12:0053S 2.40 3.35 8/24/2004 12:0053N 2.85 3.85 8/24/2004 14:005PA 0.07 0.23 8/24/2004 14:0058S 4.05 4.85 8/24/2004 14:0053S 2.75 3.40 8/24/2004 14:0053N 3.55 4.25 8/25/2004 9:005PA 0.04 0.09 8/25/2004 9:0058S 3.05 4.45 8/25/2004 9:0053S 1.50 3.35 8/25/2004 9:0053N 2.55 3.45 8/25/2004 12:005PA 0.05 0.23 8/25/2004 12:0058S 4.05 4.70 8/25/2004 12:0053S 2.40 3.35 8/25/2004 12:0053N 2.85 3.85 8/25/2004 14:005PA 0.07 0.23 8/25/2004 14:0058S 4.05 4.85 8/25/2004 14:0053S 2.75 3.40 8/25/2004 14:0053N 3.55 4.25

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163 Table F-6. Full-scale probe parameter data. Date Time Location pH Temperature (C) Conductivity (mhos/cm) Dissolved Oxygen (mg/L O2) 8/19/20049:005PA 7.0 27.9 497 3.15 8/19/20049:0058S 6.6 27.5 490 2.90 8/19/20049:0053S 6.8 28.2 489 2.95 8/19/20049:0053N 6.7 28.3 481 2.85 8/19/200412:005PA 7.0 29.8 493 3.60 8/19/200412:0058S 6.6 29.1 488 3.50 8/19/200412:0053S 6.6 29.3 492 3.60 8/19/200412:0053N 6.6 29.6 494 3.70 8/19/200414:005PA 7.0 30.2 480 3.80 8/19/200414:0058S 6.6 29.9 594 3.75 8/19/200414:0053S 6.6 30.1 533 3.60 8/19/200414:0053N 6.6 29.6 800 3.65 8/24/20049:005PA 7.10 27.9 495 3.25 8/24/20049:0058S 6.91 27.9 493 3.75 8/24/20049:0053S 6.90 28.0 494 3.50 8/24/20049:0053N 6.90 27.8 497 3.50 8/24/200412:005PA 7.20 28.8 492 3.00 8/24/200412:0058S 6.92 28.9 492 3.20 8/24/200412:0053S 6.92 28.9 489 3.60 8/24/200412:0053N 6.87 29.0 484 3.20 8/24/200414:005PA 7.11 29.6 483 3.55 8/24/200414:0058S 6.91 29.3 477 3.50 8/24/200414:0053S 6.87 29.7 480 3.45 8/24/200414:0053N 6.87 29.6 483 3.75 8/25/20049:005PA 7.14 28.3 513 3.25 8/25/20049:0058S 6.83 28.5 508 3.00 8/25/20049:0053S 6.72 28.5 507 4.15 8/25/20049:0053N 6.51 28.1 658 3.20 8/25/200412:005PA 7.23 29.1 477 3.50 8/25/200412:0058S 6.93 29.2 472 3.65 8/25/200412:0053S 6.80 29.9 467 3.50 8/25/200412:0053N 6.85 29.2 474 3.65 8/25/200414:005PA 7.18 29.2 494 3.45 8/25/200414:0058S 6.90 29.7 476 3.50 8/25/200414:0053S 6.89 29.7 470 3.40 8/25/200414:0053N 6.95 28.8 490 3.40

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164 Table F-7. Full-scale data provided by GRU. Date Time Location TSS (mg/L) Total Coliform (# /100 mL) 8/19/20049:005PA 0.3 3800 8/19/20049:0058S 0.4 0.2 8/19/20049:0053S 0.2 0.1 8/19/20049:0053N 0.4 0.3 8/19/200412:005PA 0.5 1100 8/19/200412:0058S 0.3 0.6 8/19/200412:0053S 0.5 0.3 8/19/200412:0053N 0.6 0.1 8/19/200414:005PA 0.6 1900 8/19/200414:0058S 0.8 1 8/19/200414:0053S 0.5 0.1 8/19/200414:0053N 0.4 0.1 8/24/20049:005PA 0.4 2400 8/24/20049:0058S 0.5 1.4 8/24/20049:0053S 0.3 0.2 8/24/20049:0053N 0.4 0.2 8/24/200412:005PA 0.6 1600 8/24/200412:0058S 0.2 0.7 8/24/200412:0053S 0.3 0.4 8/24/200412:0053N 0.3 0.3 8/24/200414:005PA 0.5 1100 8/24/200414:0058S 0.5 0.4 8/24/200414:0053S 0.5 0.1 8/24/200414:0053N 0.3 0.2 8/25/20049:005PA 0.3 3900 8/25/20049:0058S 0.2 3.9 8/25/20049:0053S 0.4 0.2 8/25/20049:0053N 0.3 0.2 8/25/200412:005PA 0.5 1800 8/25/200412:0058S 0.3 0.3 8/25/200412:0053S 0.4 0.3 8/25/200412:0053N 0.3 0.3 8/25/200414:005PA 0.4 2700 8/25/200414:0058S 0.3 0.2 8/25/200414:0053S 0.2 0.1 8/25/200414:0053N 0.2 0.1

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165 APPENDIX G GAS CHROMATOGRAPHY INFORMATION RT: 1.00 18.09 2 4 6 8 10 12 14 16 18 Time (min) 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 Relative Abundance 13.66 6.86 11.20 11.39 12.02 14.17 11.10 14.31 9.22 13.23 9.76 6.75 14.76 8.94 7.45 9.95 17.11 14.92 8.07 6.30 5.73 3.43 4.33 5.20 2.65 2.33 16.10 NL: 7.38E6 TIC MS 08060402 Figure G-1. Trihalomethane GC for spiked sample.

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166 RT: 0.98 18.10 2 4 6 8 10 12 14 16 18 Time (min) 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 Relative Abundance 9.17 11.12 7.26 12.76 6.92 6.32 14.34 2.00 11.39 13.70 9.77 2.83 7.45 12.04 5.21 17.59 3.43 17.10 14.95 NL: 2.38E6 TIC MS 08060403 Figure G-2. Trihalomethane GC for blank sample.

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167 RT: 0.98 18.10 2 4 6 8 10 12 14 16 18 Time (min) 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 Relative Abundance 6.10 9.18 7.28 11.12 8.18 12.78 6.31 14.34 10.16 1.97 2.13 4.17 13.71 17.59 12.42 4.32 16.87 14.91 NL: 4.57E6 TIC MS 08060404 Figure G-3. Trihalomethane GC for field sample.

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168 THM Analysis Conditions: Tekmar 3100 Purge-and-Trap Concentrator attached to a Finnigan Trace 2000 GC/MS Tekmar Conditions: Type K Trap Sample purged for 10 minutes at 40 ml/min with helium 2 minute dry purge desorb preheat 245C desorb 250C for 4 minutes bake 260C for 10 minutes GC/MS Conditions: GC:Restek Rtx-VMS capillary column, 30m x 0.32 mm i.d., 1.8 um film thickness 35C to 180C at 10C/min, initial hold at 35C for 4 minutes 180C to 200C at 25C/min MS: Electron Ionization, 34 amu to 280 amu in 0.4 seconds Source temp 200C, transfer line te mp 200C, 150uA emission current

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169 Figure G-4. Haloacetic acid GC for spiked sample.

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170 Figure G-5. Haloacetic acid GC for blank sample. Figure G-6. Haloacetic acid GC for field sample.

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171 53N 8/19 9am HAA Conditions: Hewlett-Packard 5890 Series II GC/ECD Restek DB5MS Capillary Column, 30m x 0.25 mm i.d., 0.25 um film thickness 12 psi head pressure 35C to 70C at 2.5C/min, 10 minute initial hold at 35C 70C to 210C at 5C/min Injector = 150C

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172 APPENDIX H T-TEST AND PEARSON COEFFICIENT TABLES Table H-1. Pilot-scale t-test values. Pilot Scale (n=30) t* t*(0.05) Statistical Differencet*(0.01) Statistical Difference Free Cl2 mg/L 3.281.699y 2.462y Total Cl2 mg/L 4.031.699y 2.462y TTHM g/L 1.301.699n 2.462n TTHM moles/L 1.271.699n 2.462n TTHM' g/L 2.921.699y 2.462y TTHM' moles/L 2.931.699y 2.462y HAA g/L 1.231.699n 2.462n HAA moles/L 0.461.699n 2.462n HAA' g/L 1.551.699n 2.462n HAA' moles/L 0.831.699n 2.462n Free Cl2 bl mg/L 3.011.860y 2.896y Temperature C 6.841.699y 2.462y y = yes, n = no Table H-2. Full-scale t-test values. Full Scale (n=9) t* t*(0.05) Statistical Differencet*(0.01) Statistical Difference Free Cl2 mg/L 7.971.860y 2.896y Total Cl2 mg/L 5.681.860y 2.896y TTHM g/L 0.711.860n 2.896n TTHM moles/L 0.721.860n 2.896n TTHM' g/L 2.451.860y 2.896n TTHM' moles/L 2.421.860y 2.896n HAA g/L 3.371.860y 2.896y HAA moles/L 1.931.860y 2.896n HAA' g/L 3.331.860y 2.896y HAA' moles/L 3.021.860y 2.896y y = yes, n = no

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173 Table H-3. Pilot-scale Pearson coef ficient and linear correlation values. Pilot-Scale Study r t* t*(0.05) Statistical Differencet*(0.01) Statistical Difference TTHM (g/L) vs Free Cl2 (mg/L) -0.2191.1871.701n 2.467n TTHM (mole/L) vs Free Cl2 (mg/L) -0.2251.2221.701n 2.467n TTHM' (g/L) vs Avg UV Rad (mW/cm2) 0.2991.6561.701n 2.467n TTHM' (mole/L) vs Avg UV Rad (mW/cm2) 0.2891.6001.701n 2.467n HAA (g/L) vs Free Cl2 (mg/L) -0.1190.6361.701n 2.467n HAA (mole/L) vs Free Cl2 (mg/L) 0.0490.2581.701n 2.467n HAA' (g/L) vs Avg UV Rad (mW/cm2) -0.0460.2461.701n 2.467n HAA' (mole/L) vs Avg UV Rad (mW/cm2) -0.0970.5161.701n 2.467n Free Cl2 (mg/L) vs Temp (C) -0.3441.9411.701y 2.467n Total Cl2 (mg/L) vs Temp (C) -0.2271.2331.701n 2.467n Total Cl2 (mg/L) vs Avg UV Rad (mW/cm2) -0.2811.5481.701n 2.467n Free Cl2 (mg/L) vs Avg UV Rad (mW/cm2) -0.4052.3421.701y 2.467n Avg Global Rad vs Avg UV Rad (mW/cm2) 0.99661.6431.701y 2.467y Temp (C) vs Avg UV Rad (mW/cm2) 0.8849.9931.701y 2.467y Free Cl2 (mg/L) vs Avg UV Rad (mW/cm2) bl -0.5743.7081.895y 2.998y TTHM (g/L) vs Free Cl2 (mg/L) bl -0.2891.5951.895y 2.998n Free Cl2 (mg/L) vs Temp (C) bl -0.3191.7811.895n 2.998n Temp (C) (OPAQ) vs Avg UV Rad (mW/cm2) 0.7866.7321.701y 2.467y Temp (C) (TRANS) vs Avg UV Rad (mW/cm2) 0.93413.8201.701y 2.467Y y = yes, n = no

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174 Table H-4. Full-scale pearsons coefficient and linear correlation values. Full-Scale Study (n=9) r t* t*(0.05) Statistical Differencet*(0.01) Statistical Difference TTHM (g/L) vs Free Cl2 (mg/L) 0.4231.2371.895n 2.998n TTHM (mole/L) vs Free Cl2 (mg/L) 0.4311.2641.895n 2.998n TTHM' (g/L) vs Temp (C) -0.2460.6721.895n 2.998n TTHM' (mole/L) vs Temp (C) -0.2500.6821.895n 2.998n HAA (g/L) vs Free Cl2 (mg/L) -0.3941.1341.895n 2.998n HAA (mole/L) vs Free Cl2 (mg/L) -0.2210.5991.895n 2.998n Free Cl2 (mg/L) vs Temp (C) -0.1220.3251.895n 2.998n Total Cl2 (mg/L) vs Temp (C) -0.0880.2331.895n 2.998n y = yes, n = no

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175 LIST OF REFERENCES 1. Pregeant, Charles W. Trihalomethane Formation Potential in a Denitrification Wastewater Treatment Plant. Department of Environmental Engineering and Sciences, University of Florida. 1992. 2. Barrios, Carlos, Terese Gregg, Robert Harris, Kenneth Mayorga, Mario Ortiz, and Nick Teague. Minimizing Chlorine Loss in the Chlorine Contact Basins at the Kanapaha Water Reclamation Facility. Integrated Product and Process Design (IPPD). Gainesville Regional Utilities. 28 April 2002. 3. Bitton, Gabriel. Wastewater Microbiology, 2nd Edition John Wiley and Sons, Inc. New York. 1999. 4. Sawyer, Chair N., Perry L. McCarty, and Gene F. Parkin. Chemistry for Environmental Engineering 4th Edition McGraw-Hill,Inc.New York. 1994. 5. Weiner, Ruth F. and Robin Matthews. Environmental Engineering, 4th Edition Butterworth Heinemann. Amsterdam. 2003. 6. White, Geo Clifford. Handbook of Chlorination 2nd Edition Van Nonstrand Reinhold Company. 1986. pg 165. 7. Snoeyink, Vernon L. and David Jenkins. Water Chemistry John Wiley and Sons, Inc. New York. 1980. 8. Singer, Philip Formation and Control of Disinfection By-Products in Drinking Water American Water Works Association. Phillip C. Singer, Editor. Denver, Colorado. 1999. 9. Zhang, Xiangru and Roger A. Minear. Characterization of High Molecular Weight Disinfection Byproducts Resulting from Ch lorination of Aquatic Humic Substances. Environmental Science and Technology. Vol. 36, 2002. pg 4033-4038. 10. Singer, Phillip C., Richard A. Brown, Joseph F. Wiseman, Jr. Formation of Halogenated Organics During Wastewater Disinfection Water Resources Research Institute, University of North Ca rolina. Report No. 239. November 1988. 11. Xie, Yuefeng F. Disinfection By-products in Drinking Water: Formation, Analysis, and Control Lewis Publishers. Boca Raton, Florida. 2004.

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176 12. US EPA. National Primary Drinking Wa ter Regulation. Federal Register. 1998 63(241), 69390. 13. Final Report: Mathematical Modeling of the Formation of THMs and HAAs in Chlorinated Natural Waters Prepared by: Montgomery Watson. American Water Works Association. March 1993. 14. Crou, Jean-Philippe, David Violleau, and Lawrence Labouyrie. Disinfection ByProduct Formation Potentials of Hydrophobic and Hydrophilic Natural Organic Matter Fractions: A Comparison Between a Lowand a High-Humic Water. Natural Organic Matter and Disinfection By-Products: Characterization and Control in Drinking Water ACS Symposium Series 761. Editor: Sylvia E. Barrett, Stuart W. Krasner, and Gary L. Amy. Am erican Chemical Society. Washington, D.C. 2000. 15. Wu, Wells W., Paul A. Chadik, William M. Davis, Joseph J. Delfino, and David J. Powell. The Effect of Structural Charac teristics of Humic Substances on Disinfection By-Product Formation in Chlorination. Natural Organic Matter and Disinfection By-Products: Characteriza tion and Control in Drinking Water ACS Symposium Series 761. Edited by: Sylvia E. Barrett, Stuart W. Krasner, and Gary L. Amy. American Chemical Society. Washington, D.C. 2000. 16. Gang, Dianchen, Thomas E. Clevenger, and Shankha K. Banerji. Relationship of Chlorine Decay and THMs Formation to NOM Size. Journal of Hazardous Materials. A96, 2003. pg 1-12. 17. Liang, Lin and Philip Singer. Factors Influencing the Formation and Relative Distribution of Haloacetic Acids and Trihalomethanes in Drinking Water. Environmental Science and Technology. Vol. 37, No.13, 2003. pg 2920-2928. 18. Wu, Wells W. and Paul A. Chadik. Effects of Bromide on Haloacetic Acid Formation During Chlorination of Biscayne Aquifer Water. Journal of Environmental Engineering. October 1998. pg 932-938. 19. Westerhoff, P., P. Chao, and H. Mash. Reactivity of Natural Organic Mater with Aqueous Chlorine and Bromine. Water Research. Vol. 38, 2004. pg 1502-1513. 20. Kim, Junsung, Yong Chung, Dongchun Shin, Myungsoo Kim, Yonghun Lee, Youngwook Lim, and Duckhee Lee. Chlorination by-products in Surface Water Treatment Process. Desalination. Vol. 151, 2002. pg 1-9. 21. Espigares, Miguel, Pablo Lardelli, Pedro Ortega, Evaluating Trihalomethane Content in Drinking Water on the Basi s of Common Monitoring Parameters: Regression Models. Journal of Environmental Health. October 2003. pg 9-13.

PAGE 194

177 22. Acra, A., M. Jurdi, H. Mu'allem, Y. Karahagopian, and Z. Raffoul. Water Disinfection by Solar Radiation: Assessment and Application. International Development Research Centre. Ottawa, Onatrio. 1990. 23. Caslake, Laurie F., Daniel J. Connolly, Vilas Menon, Catriona M. Duncanson, Ricardo Rojas, and Javad Tavakoli. Disinfection of Contaminated Water by Using Solar Irradiation. Applied and Environmental Microbiology. February 2004. pg 1145-1150. 24. Salih, Fadhil M. Formualtion of a Mathmatical Model to Predict Solar Water Disinfection. Water Research. Vol. 37, 2003. pg 3921-3927. 25. Saitoh, Takeo S. and Hamdy H. El-Ghetany. A Pilot Solar Water Disinfecting System: Performance Analyses and Testing. Solar Energy. Vol. 72, No.3, 2002. pg 261-269. 26. Rijal, G.K. and R.S. Fujioka. Use of Reflectors to Enhan ce the Synergistic Effects of Solar Heating and Solar Wavelengths to Disinfect Drinking Water Sources. Water Science and Technology. Vol. 48, No. 11-12, 2003. pg 481-488. 27. Yukselen, Mehmet Ali, Baris Calli, Orhan Gokyay, and Ahmet Saatci. Inactivation of Coliform Bacteria in Black Se a Waters due to Solar Radiation. Environmental International. Vol. 29, 2003. pg 45-50. 28. Sinton, Lester W., Rochelle K. Finlay, and Philippa A. Lynch. Sunlight Inactivation of Fecal Bacteriophages and Ba cteria in Sewage-Polluted Seawater. Applied and Environmental Microbiology. August 1999. pg 3605-3613. 29. Hassen, Abdennaceur, Meryem Mahrouk, Hadda Ouzari, Mohamed Cherif, Abdellatif Boudabous, and Jean Jacques Damelincourt. UV Disinfection of Treated Wastewater in a Large-Scale Pilot Plant and Inactivation of Selected Bacteria in a Laboratory UV Device. Bioresource Technology. Vol. 74, 2000. pg 141-150. 30. United States Environmental Protection Agency. Methods for Organic Chemical Analysis of Municipal and Industrial Wastewater. Method 624-Purgeables. Appendix A to Part 136. 31. United States Environmental Protection Agency. Determination of Haloacetic Acid and Dalapon in Drinking Water by LiquidLiquid Extraction, Derivation and Gas Chromatography with Electron Capture Detection. Method 552.2.1995. 32. McBean Edward A and Frank A Rovers. Statistical Procedures for Analysis of Environmental Monitoring Data and Risk Assessment, Volume 3 Prentice Hall PTR. 1988.

PAGE 195

178 BIOGRAPHICAL SKETCH Heather Fitzpatrick was born March 26, 1980. She and her father and two sisters moved to Florida when she was 7 years old. She attended the Center for Advanced Technologies, a magnet high school in St. Pete rsburg, Florida. Af ter graduating high school, she went on to receive a bachelors degree in Environmental Engineering at the University of Florida (UF; Gainesville) in 2002. She stayed at UF to pursue a Master of Engineering degree, also in environmental e ngineering, giving her the opportunity to work on this study with Dr. Paul A. Chadik and Gainesville Regi onal Utilities (GRU). While pursuing her masters degree, she married Anthony J. Manganiello, III, in May 2004.


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Title: Covering Chlorine Contact Basins at the Kanapaha Water Reclamation Facility: Effects on Chlorine Residual, Disinfection Effectiveness, and Disinfection By-Product Formation
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Material Information

Title: Covering Chlorine Contact Basins at the Kanapaha Water Reclamation Facility: Effects on Chlorine Residual, Disinfection Effectiveness, and Disinfection By-Product Formation
Physical Description: Mixed Material
Copyright Date: 2008

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COVERING CHLORINE CONTACT BASINS AT THE KANAPAHA WATER
RECLAMATION FACILITY: EFFECTS ON CHLORINE RESIDUAL,
DISINFECTION EFFECTIVENESS, AND DISINFECTION BY-PRODUCT
FORMATION















By

HEATHER L. FITZPATRICK


A THESIS PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE
REQUIREMENTS FOR THE DEGREE OF MASTER OF ENGINEERING

UNIVERSITY OF FLORIDA


2005

































Copyright 2005

by

Heather L Fitzpatrick
















ACKNOWLEDGMENTS

I would like to thank my supervisory committee members (Dr. Paul Chadik, Dr.

David Mazyck, and Dr. Benjamin Koopman) for their input and assistance during this

investigation. Special thanks go to my supervisory committee chair (Dr. Chadik) for his

technical support and guidance during this study; they were of immeasurable significance

to this research and to me. Also, I would like to thank the Gainesville Regional Utilities

staff for their support throughout the course of this research. The help of Christina Akly

in the field and at the University of Florida was of great importance and greatly

appreciated. I would also like to thank my family, friends, and especially my husband for

their continuous support during my graduate career.
















TABLE OF CONTENTS

page

A C K N O W L E D G M E N T S ................................................................................................. iii

LIST OF TABLES ............. ......... .. ........................... .......... vii

LIST OF FIGURES ....................... ........................ .... .. ................. .x

ABSTRACT .......................................... .......... xvi

CHAPTER

1 IN TR OD U CTION .................. ............................. .. ...... ................... .

P ilo t S tu d y ........................................................... ................ 5
F u ll-S cale Stu dy ...................................... .............................. ................ .. 7
C larifier C hlorine A addition .......................................... .................................7

2 REVIEW OF LITERATURE ............................................................... .............9

N itrification/D enitrification............................................................... ...... .......9
Chlorine Disinfection .................. ..................................... .... ....... 10
Free C chlorine ....................................................... .............. ...... 11
C om bined C hlorine .............................. ........................ .. ........ .... ............12
B reak-P oint C hlorination ............................................................... ............... 13
C o n tact T im e .................................................... ................ 14
D isinfection B y-Product Form ation ........................................ .............................15
Sunlight/U V Irradiation ........... ........................................................ ............... 23

3 M ATERIALS AND M ETH OD S ........................................ ........... ..............27

M measured Param eters ............. ........................ .... .... ............. ..... 27
G lobal Solar R radiation ............................................................ ............... 27
U ltrav iolet R radiation ............................................... .. ........ .. .....................2 7
Total and Free Chlorine Residual.........................................................28
T otal Su spended Solids ............................................... .......................... ........ 29
Total Coliform ................................................ .........................................29
Trihalom ethane (TH M ) ................................................ ............ ............... 30
H aloacetic A cid (H A A ) .............................................. ..... ...... ............... 30
p H ............................................................................................. 3 1









C o n du ctiv ity ................................................................ 3 1
D dissolved O xygen ................. .... .......................... .. ........ ................ 32
S a m p lin g ......................................................................................................3 2
Pilot Scale System ............................ ................ 32
W astew after Feed System M aterials................................... ................34
C hlorin e D o sing ............. ........................ .................................. ........... ...... 37
P u m p T e st ...................................................................................................... 3 7
F u ll S c a le .................................................................. 3 8
C calculation s ................................................................40
Disinfection By-Product Data Normalization ................................. ........40
Trihalom ethane norm alization .......................................................40
Haloacetic acid normalization .................................... .......... 42
Average Radiation ..... .......... ......... ......... .........43
Standard D aviation ...........................................................44
P aired T -T est ........... ......... ........................................ ............................ 44
L near C correlation .............................................................. 4 5

4 DISCUSSION: PILOT-SCALE BASIN .......................................................47

Solar Radiation/Temperature .............. .......................47
C hlorin e R esidu al ........................................ .......................................... 50
Free Chlorine ......... ... ................................. ...... .. ........ ........ .... 51
Total C hlorine.................................................. 57
D isinfection By-Products.................................................................. ...... 60
Trihalomethane ................. ....... ................61
H alo a c etic A cid ............................................................................................. 7 4

5 DISCUSSION: FULL-SCALE STUDY .......................................................86

C h lo rin e R e sid u al ................................................................................................. 8 6
F ree C h lo rin e .......... .... ..... ....................................................................... 8 6
Total Chlorine................. ..............................89
D isinfection B y-Products......................................... .................................. 91
Trihalom ethane ........... .... ........ ... ................... .... .. .. .. ............... 91
Haloacetic Acid ................................... .. .. .... .. .............101

6 DISCUSSION: MEASURED PARAMETERS ....................................................... 112

T em p eratu re ...... .. .. ...... ..... ... .. ........ .................. ....................................... 12
T o ta l C o lifo rm ............................................................................................1 12
Total Suspended Solids............................................ .................... ...........113
pH ......................................................... .............. .... ...... ...... ..... 114
C onductivity .............. ................................. ......... .... ...... .. ............ 115
D issolv ed O x y g en ...............................................................................1 15

7 CON CLU SION S ................................................ ....... .......... ..... 117



v









APPENDIX

A PILOT-SCALE BASIN DESIGN ........................................ ......................... 121

B FLUOROSCEIN TRACER ANALYSIS ....................................... ............... 122

C CHLORINE DOSING CALCULATIONS ..................................... ............... 126

D C O M P IL E D D A T A ......................................................................... .................... 127

E PILO T-SCALE D A TA ............................................................. .. ............... 139

F FU LL-SCALE D A TA .......................................................................... ............... 157

G GAS CHROMATOGRAPHY INFORMATION.....................................................165

H T-TEST AND PEARSON COEFFICIENT TABLES............................................ 172

L IST O F R E F E R E N C E S ........................................................................ .................... 175

BIOGRAPHICAL SKETCH .............................................................. ...............178
















LIST OF TABLES


Table pge

3-1 Chlorine contact basin dimension ratios. ..................................... ............... 33

3-2 Pilot chlorine contact basin dim ension.................................. ....................... 33

4-1 Normalization factors used to normalize OPAQ TTHM effluent concentrations to
TRANS TTHM effluent concentrations....................... ... ....................... 68

4-2 Normalization factors used to normalize OPAQ HAA(5) effluent concentrations to
TRANS HAA(5) effluent concentrations................................. .... .............80

5-1 Normalization factors used to normalize COV TTHM effluent concentrations to
UNCOV TTHM effluent concentrations....................... ... ....................... 97

5-2 Normalization factors used to normalize COV HAA(5) effluent concentrations to
UNCOV HAA(5) effluent concentrations..................... ..................... 108

A -i South chlorine contact basin ............................................................................ 121

A -2 N orth chlorine contact basin ............................................................................ 121

A -3 Pilot basin. .....................................................................................................121

B-l Fluoroscein tracer at KWRF pilot basin, clear top ...............................................122

B -2 Conditions during tracer analysis ................................... ..................................... 123

B-3 Flouroscein F curve calculation. ........................................ ....................... 124

B-4 The F curve values. ........................ ....... .. .. ........ ............... 125

C-l Chlorine dosing during pilot-scale study. ................................... ............... 126

C-2 Acid and base addition during pilot-scale study. ................................................126

D-l Pilot-scale study compiled and calculated parameter data................................... 127

D-2 Pilot-scale study compiled chlorine data and differences .....................................128

D-3 Pilot-scale study compiled TTHM data and differences ............... .................129









D-4 Pilot-scale study compiled TTHM and normalization factors ............................130

D-5 Pilot-scale study compiled normalized TTHM' data and differences..................131

D-6 Pilot-scale study compiled HAA(5) data. ................................... ............... 132

D-7 Pilot-scale study compiled normalized HAA(5) data. .........................................133

D-8 Pilot-scale study compiled differences in HAA(5) and HAA(5)' data ................134

D-9 Full-scale study compiled and calculated parameter data............... .................135

D-10 Full-scale study compiled chlorine data and differences. ......................................135

D-11 Full-scale study compiled TTHM data and differences. ......................................136

D-12 Full-scale study compiled TTHM and normalization factors. ...........................136

D-13 Full-scale study compiled normalized TTHM' data and differences.....................137

D-14 Full-scale study compiled HAA(5) data ...............................................137

D-15 Pilot-scale study compiled normalized HAA(5) data. .........................................138

D-16 Full-scale study compiled differences in HAA(5) and HAA(5)' data .................138

E-1 Trihalomethane mass concentrations in the pilot-scale study.............................139

E-2 Trihalomethane molar concentrations in the pilot-scale study..............................142

E-3 Haloacetic acid mass concentrations in the pilot-scale study..............................144

E-4 Haloacetic acid molar concentrations in the pilot-scale study ............................146

E-5 Pilot-scale study chlorine effluent concentrations..................... ...............148

E-6 Pilot-scale probe param eter data. ........................................ ....................... 151

E-7 Pilot-scale data provided by GRU laboratory. ............................... ......... ...... 154

F-l Trihalomethane mass concentrations in the full-scale study...............................157

F-2 Trihalomethane molar concentrations in the full-scale study. ............................159

F-3 Haloacetic acid mass concentrations in the full-scale study. ...............................160

F-4 Haloacetic acid molar concentrations in the full-scale study...............................161

F-5 Full-scale study chlorine effluent concentrations......... .................. ................ 162









F-6 Full-scale probe parameter data. ........................................ ....................... 163

F-7 Full-scale data provided by GRU ................................... .....................................164

H P ilot-scale t-test values ......... ................. .................................... ....................... 172

H -2 Full-scale t-test values .................................................. .............................. 172

H-3 Pilot-scale Pearson coefficient and linear correlation value...............................173

H-4 Full-scale Pearson coefficient and linear correlation values ...............................174















LIST OF FIGURES


Figure p

1-1 Kanapaha Water Reclamation Facility flow diagram. .............................................1

1-2 O overhead layout of the K W R F .............................................................................

1-3 Wastewater process from filtration through chlorination. .......................................2

1-4 C hlorine addition at the clarifiers .................................................................... ....8

2-1 Percent of free chlorine compound (HOC1 and OCE) versus pH ........................... 11

2-2 Breakpoint chlorination: Species of chlorine residuals present during chlorination
w hen am m onia is present. ........................................ ........................................ 14

2-3 T he T H M species. .......................... ...... ............................... ..... ........16

2-4 T he H A A (5) species ..... .................................................................. .... .17

2-5 Predicted versus the observed concentration of CHC13 for the entire model
development database from the 1993 AWWA report....................... ................22

2-6 Predicted versus the observed concentration of DCAA for the entire model
development database from the 1993 AWWA report....................... ................23

3-1 Radiometer, pyranometer, and datalogger setup............................................... 28

3-2 P ilot basin system setup. ........................................ ............................................35

3-3 Pilot scale setup; chlorine and acid/base solution containers, solution pumps,
influent water spigot, static mixers, t-split, TRANS and OPAQ basins. ................36

3-4 Full-scale setup. (a) Uncovered side of the basin. (b) Covered side of the basin
during the full-scale study. ...... ........................... .......................................38

3-5 Sampling points in the post-aeration basin and North chlorine contact basin for the
full-scale study .......................................................................39

4-1 Average global horizontal radiation versus the average UV radiation...................48

4-2 The effluent temperature of the TRANS and OPAQ basins plotted versus the
average UV radiation exposure of the TRANS basin over the HRT ..................49









4-3 Difference in effluent temperature of the basins (TRANS-OPAQ) plotted versus the
average U V radiation over the HRT. ............................................ .....................50

4-4 Free chlorine residual sampling sets in particular residual ranges for the TRANS
and OPA Q basins. ................................... ... .. ....... .............. .. 52

4-5 Free chlorine residual difference of the TRANS and OPAQ basins
(TRANS-OPAQ) plotted versus average UV Radiation over the HRT of the
wastewater in the basin for all pilot studies. ................................. .................53

4-6 Free chlorine residual difference of the OPAQ and TRANS basins
(TRANS-OPAQ) plotted versus average UV radiation over the HRT of the
wastewater in the basin for baseline parameters. ............................................. 54

4-7 Free chlorine difference of the TRANS and OPAQ basins (TRANS-OPAQ) plotted
versus the difference in temperature for all of the pilot studies.............................55

4-8 Free chlorine difference of the TRANS and OPAQ basins (TRANS-OPAQ) plotted
versus the difference in temperature for baseline parameters................................56

4-9 Total chlorine residual sampling sets in particular residual ranges for the TRANS
and OPA Q basins. ................................... ... .. ....... .............. .. 58

4-10 Total chlorine residual difference of the OPAQ and TRANS basins (TRANS-
OPAQ) plotted versus average UV Radiation over the HDT of the wastewater in
the basin for all pilot studies. ............................................................................ 59

4-11 Total chlorine residual difference of the TRANS and OPAQ basins (TRANS-
OPAQ) plotted versus the difference in temperature between the basins ...............60

4-12 The TTHM effluent mass concentrations for the TRANS and OPAQ basins are
show n in range increm ents. ........................................ .........................................62

4-13 The TTHM effluent molar concentrations for the TRANS and OPAQ basins are
show n in range increm ents. ........................................ .........................................62

4-14 Difference in TTHM concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into mass concentration ranges. .................................64

4-15 Difference in TTHM concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into molar concentration ranges................................64

4-16 Difference in TTHM effluent mass concentration of the TRANS and OPAQ basins
(TRANS-OPAQ) plotted versus the difference in free chlorine residual of the
TR A N S and O PA Q basins. ........................................................... .....................65









4-17 Difference in TTHM effluent molar concentration of the TRANS and OPAQ basins
(TRANS-OPAQ) plotted versus the difference in free chlorine residual of the
TR A N S and O PA Q basins. ........................................................... .....................65

4-18 Difference in TTHM mass effluent concentration between the TRANS and OPAQ
basins (TRANS-OPAQ) plotted versus the difference in free chlorine residual
between the TRANS and OPAQ basins for baseline runs. ......................................66

4-19 Speciation of the THM formation in the TRANS effluent on a mass basis sampled
at 9 am on A ugust 23, 2004........................................................... ............... 67

4-20 Normalized TTHM effluent mass concentrations for the TRANS and OPAQ basins
are show n in range increm ents. ........................................ .......................... 69

4-21 Normalized TTHM effluent molar concentrations for the TRANS and OPAQ
basins are shown in range increments. ......................................... ...............69

4-22 Difference in TTHM' concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into mass concentration ranges. .................................70

4-23 Difference in TTHM' concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into molar concentration ranges................................71

4-24 Difference in normalized TTHM mass concentration of the TRANS and the OPAQ
basins (TRANS-OPAQ) plotted versus the average UV radiation. exposure over the
H R T .................................................................................72

4-25 Difference in normalized TTHM molar concentration of the TRANS and the
OPAQ basins (TRANS-OPAQ) plotted versus the average UV radiation exposure
ov er th e H R T ...................................................... ................ 7 3

4-26 The HAA(5) effluent mass concentrations for the TRANS and OPAQ basins are
show n in range increm ents. ........................................ ........................................75

4-27 The HAA(5) effluent molar concentrations for the TRANS and OPAQ basins are
show n in range increm ents. ........................................ ........................................75

4-28 Difference in HAA(5) concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into mass concentration ranges. .................................76

4-29 Difference in HAA(5) concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into molar concentration ranges................................76

4-30 Difference in HAA(5) mass concentration of the TRANS and the OPAQ basins
(TRANS-OPAQ) plotted versus the difference in free chlorine residual of the
TRANS and OPAQ basins (TRANS-OPAQ). ................................. ...............77









4-31 Difference in HAA(5) molar concentration of the TRANS and the OPAQ basins
(TRANS-OPAQ) plotted versus the difference in free chlorine residual of the
TRANS and OPAQ basins (TRANS-OPAQ). ................................. ...............78

4-32 Speciation of the HAA(5) formation in the OPAQ effluent on a mass basis sampled
at 12 pm on August 30, 2004. ............................................................................79

4-33 The HAA(5)' effluent mass concentrations for the TRANS and OPAQ basins are
show n in range increm ents. ........................................ ........................................81

4-34 The HAA(5)' effluent molar concentrations for the TRANS and OPAQ basins are
show n in range increm ents. ........................................ .......................................81

4-35 Difference in HAA(5)' concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into mass concentration ranges. ..................................82

4-36 Difference in HAA(5)' concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into molar concentration ranges................................83

4-37 Difference in HAA(5)' effluent mass concentration of the TRANS and OPAQ
basins (TRANS-OPAQ) plotted versus the average UV radiation exposure over the
H R T .................................................................................84

4-38 Difference in HAA(5)' effluent molar concentration of the TRANS and OPAQ
basins (TRANS-OPAQ) plotted versus the average UV radiation exposure over the
H R T .................................................................................84

5-1 Free chlorine residual of the UNCOV and COV side effluents separated into
concentration ranges .................................................... ..... .. ........ .... 87

5-2 Difference in free chlorine residual between the UNCOV and COV sides
(UNCOV-COV) separated into concentration ranges ............................................88

5-3 Free chlorine difference of the UNCOV and COV basin sides plotted versus the
difference in tem perature. ............................................................. .....................89

5-4 Total chlorine residual of the UNCOV and COV side effluents separated into
concentration ranges........... .......................................... .............. .. .... ..... .90

5-5 Total chlorine difference of the UNCOV and COV basin sides plotted versus the
difference in tem perature. ............................................................. .....................9 1

5-6 The TTHM effluent mass concentrations for the UNCOV and COV sides are
show n in range increm ents. ........................................ .......................................92

5-7 The TTHM effluent molar concentrations for the UNCOV and COV sides are
show n in range increm ents. ............................................................ .....................93









5-8 Difference in TTHM concentration between the UNCOV and COV sides
(UNCOV-COV) separated into mass concentration ranges.................................94

5-9 Difference in TTHM concentration between the UNCOV and COV sides
(UNCOV-COV) separated into molar concentration ranges. ................................94

5-10 Difference in the TTHM effluent mass concentration between the UNCOV and
COV sides (UCOV-COV) plotted versus the difference in free chlorine residual of
the UNCOV and COV sides (UCOV-COV). .................... .......................... 95

5-11 Difference in the TTHM effluent molar concentration between the UNCOV and
COV sides (UCOV-COV) plotted versus the difference in free chlorine residual of
the UNCOV and COV sides (UCOV-COV). .................... .......................... 96

5-12 Speciation of the TTHM formed in the UNCOV side sampled at 9 am on August
2 5 2 0 0 4 .......................................................................... 9 6

5-13 The TTHM' mass concentration instances separated into concentration ranges for
the UNCOV and COV side. ...... ........................... ......................................98

5-14 The TTHM' molar concentration instances separated into concentration ranges for
the UNCOV and COV side. ...... ........................... ......................................99

5-15 Difference in TTHM' concentration between the UNCOV and COV sides
(UNCOV-COV) separated into mass concentration ranges................................100

5-16 Difference in TTHM' concentration between the UNCOV and COV sides
(UNCOV-COV) separated into molar concentration ranges. .............................101

5-17 The HAA(5) effluent mass concentrations for the UNCOV and COV sides are
show n in range increm ents. ............................................. ............................ 102

5-18 The HAA(5) effluent molar concentrations for the UNCOV and COV sides are
show n in range increm ents. ............................................. ............................ 103

5-19 Difference in HAA(5) concentration between the UNCOV and COV sides
(UNCOV-COV) separated into mass concentration ranges................................104

5-20 Difference in HAA(5) concentration between the UNCOV and COV sides
(UNCOV-COV) separated into molar concentration ranges. .............................104

5-21 Difference in HAA(5) effluent mass concentration of the UNCOV and COV sides
versus the difference in free chlorine residual of the UNCOV and COV sides.....105

5-22 Difference in HAA(5) effluent molar concentration of the UNCOV and COV sides
versus the difference in free chlorine residual of the UNCOV and COV sides.....106









5-23 Speciation of the HAA(5) formation in the COV effluent on a mass basis sampled
at 12 pm on A ugust 25, 2004. ........................................................................... 107

5-24 The HAA(5)' effluent mass concentrations for the UNCOV and COV basin sides
are shown in range increm ents. ........................................ ......................... 109

5-25 The HAA(5)' effluent molar concentrations for the UNCOV and COV basin sides
are shown in range increm ents. ........................................ ......................... 109

5-26 Difference in HAA(5)' concentration between the UNCOV and COV sides
(UNCOV-COV) separated into mass concentration ranges................................110

5-27 Difference in HAA(5)' concentration between the UNCOV and COV sides
(UNCOV-COV) separated into molar concentration ranges ..............................111

6-1 Total coliform and temperature plotted against sampling time on July 14, 2004..113

6-2 Total suspended solids and temperature plotted against sampling time on July 14,
2 0 0 4 ................................ ................... ..................... ................ 1 1 4

6-3 pH and temperature plotted against sampling time on July 14, 2004 ..................114

6-4 Conductivity and temperature plotted against sampling time on July 14, 2004....115

6-5 The D.O. and temperature plotted against sampling time on July 14, 2004..........116

B-l Fluoroscein versus sampling time. .............................................. ............... 124

B -2 The F curve..................................................... ...................... ...... ....... 125

G-1 Trihalomethane GC for spiked sample........................................ ............... 165

G-2 Trihalomethane GC for blank sample. ....................................... ............... 166

G-3 Trihalom ethane GC for field sample ............................................... ............... 167

G-4 Haloacetic acid GC for spiked sample. ...................................... ............... 169

G-5 Haloacetic acid GC for blank sample................. ....... ...... ................... .............. 170

G-6 Haloacetic acid GC for field sample. ........................................ ............... 170















Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the Requirements for the Degree of
Master of Engineering

COVERING CHLORINE CONTACT BASINS AT THE KANAPAHA WATER
RECLAMATION FACILITY: EFFECTS ON CHLORINE RESIDUAL,
DISNIFECTION EFFECTIVENESS, AND DISINFECTION BY-PRODUCT
FORMATION

By

Heather L. Fitzpatrick

May 2005

Chair: Paul A. Chadik
Major Department: Environmental Engineering Sciences

It is commonly understood that sunlight, specifically ultraviolet (UV) radiation,

degrades chlorine and thus reduces chlorine residual in uncovered chlorine contact

basins. Its effect on disinfection by-product (DBP) formation, however, has not been

significantly studied. A pilot and full-scale study were performed at the Kanapaha Water

Reclamation Facility (KWRF) to investigate the effect of UV radiation on chlorine

residual, disinfection-by-product formation, and inactivation of bacteria.

For both the pilot and full-scale studies, two chlorine disinfection processes were

setup in parallel, for effluent parameter comparisons. One process allowed for the

exposure of the wastewater to UV radiation. In the other process an opaque cover was

used to prevent solar radiation exposure of the wastewater during chlorine disinfection.

Preventing UV radiation exposure of wastewater provided higher chlorine residuals (on

average 0.4 and 0.7 mg/L free chlorine higher) for pilot and full-scale averages









respectively. Extent of chlorine loss from UV radiation exposure was directly

proportional to the UV exposure intensity during chlorine disinfection. Both processes,

with and without UV radiation exposure, provided adequate total coliform inactivation.

To compensate for the difference in effluent conditions (such as chlorine residual

and temperature), the effluent DBP concentrations were normalized. In the normalization

process, non-exposed effluent DBP concentrations were normalized to UV-exposed

effluent DBP concentrations using normalization factors. Normalization factors were

calculated from parameter data collected during each sampling run. By preventing UV

radiation exposure during chlorine disinfection, free chlorine residual was found to be

significantly higher, and also the total trihalomethane effluent concentration was found to

be significantly less (on average 17.1 and 7.5 [tg/L less for normalized concentrations)

than for pilot and full-scale averages, respectively. In the full-scale study haloacetic acid

(HAA(5)) concentration was significantly less in the process that prevented UV radiation

exposure (on average, 39.0 [tg/L less). However, the pilot-scale did not show the same

degree of HAA(5) concentration difference; thus, no significant difference was found

between the UV radiation exposed and non-exposed processes. Preventing UV radiation,

if it does not lessen HAA(5) formation, does not increase formation.

Our studies provide evidence contrary to common theory that an increase in free

chlorine during chlorination will result in higher DBP formation. The significance lies in

using chlorine disinfection processes where wastewater is covered to prevent UV-

radiation exposure. When used it could lower the amount of chlorine loss, and help to

lower DBP formation.

















CHAPTER 1
INTRODUCTION

The Kanapaha Water Reclamation Facility (KWRF), owned and operated by


Gainesville Regional Utilities (GRU), treats wastewater from the west side of


Gainesville, Florida, and its outlying areas. The plant uses a modified Ludzak-Ettinger


process to treat the wastewater.' The plant operation promotes biological removal of


nitrogen and carbonaceous biological oxygen demand (CBOD). After the aeration


basins, the wastewater moves to the clarifiers (where solids are removed). Then the


wastewater flows through filters (which remove the fine particles that did not settle out in


the clarifiers). The wastewater is then collected in a clearwell, sent to the post-aeration


basin, and then disinfected in the chlorine contact basins (Figure 1-1).







Im fluen



S ClrHie Chlorine -
Contact
Basin -
Sludge Dewoleringw -
-- Sludge Digeslers

Wase Sludge

Sludge Thickener 0--
H hRecharge Wells
Holding Pond






Figure 1-1. Kanapaha Water Reclamation Facility flow diagram.









The plant (Figure 1-2) was recently expanded from a 10 million gallon per day

(MGD) to a 14 MGD capacity. A schematic of the wastewater process from filtration

through the chlorine contact basins is shown in (Figure 1-3).


Figure 1-2. Overhead layout of the KWRF.


I I I


Figure 1-3. Wastewater process from filtration through chlorination.


I [6 Filters









From the clarifiers, the wastewater is sent to six filters setup in parallel. The filter

effluents combine into a single 100,000-gallon clearwell. Chlorine gas is injected into

the pipe as the wastewater flows from the post-aeration basin to the first of two chlorine

contact basins, to begin the disinfection stage of the treatment process. The two chlorine

contact basins are setup in series (the North and the South chlorine contact basins). The

first chlorine contact basin (the North basin), with a volume of 0.16 MG, is part of the

original plant. The wastewater then flows to a second chlorine contact basin (the South

basin) with a volume of 0.57 MG. The South basin was added after the original plant

was built, to increase treatment capacity. A previous study at the KWRF determined that

the North and South basins together model as 60 tanks-in-series while the North basin

models as 100 tanks-in-series separately.2

As stated, the KWRF relies on chlorine to disinfect the wastewater. Enough

chlorine gas is injected to create sufficient free chlorine to meet the chlorine demand of

the wastewater and leave enough effluent residual to meet the standards set by the

Environmental Protection Agency (EPA) and upheld by the Florida Department of

Environmental Protection (FDEP). According to the KWRF permit, the effluent must

have at least a 1 mg/L Cl2 free chlorine residual. In the chlorination process at the

KWRF, the contact basins are open to the environment; allowing the wastewater to be

exposed to UV radiation from sunlight. The UV radiation acts as a catalyst to reduce the

free chlorine (Equation 1-1). This reduction leads to an appreciable amount of chlorine

loss due to UV radiation exposure.

2HOCl u 2H + 2C + 02 (1-1)









Since the KWRF injects treated wastewater into deep wells in the Floridan aquifer

(a drinking water source), and is used in reuse applications, the finished wastewater must

meet EPA and DEP permit requirements. Disinfection by-product formation is of

increasing concern, since these by-products are linked to harmful health effects.

Pregeant1 using wastewater from the KWRF showed a positive correlation between free

chlorine residual and THM formation. As the chlorine residual was increased the THM

concentration formed also increased, given that there were THM precursors left in the

wastewater to react.

In a previous study performed by the Integrated Product and Process Design

(IPPD) team sponsored by Gainesville Regional Utilities (GRU) in 2001-2002 the

chlorine loss at the KWRF was investigated.2 Most chlorine loss was assumed to result

from chlorine decay by ultraviolet (UV) irradiation (Equation 1-1). Thus it was

suggested that covering the basin would decrease chlorine loss caused by this

mechanism.

The IPPD study provided good insight into the hydrodynamic behavior of the

treated wastewater as to flows through the chlorine contact basins and the disinfection

process at the KWRF. The study comprises two days worth of data compilation, March

19th and January 24th, for chlorine concentration, total trihalomethane (TTHM)

concentration, and the volume of water irradiated by sunlight. In the study one side of

the chlorine contact basin was covered with a polypropylene tarp while the other side was

left open. The covered side of the basin had a higher chlorine residual than the

uncovered basin verifying a definite correlation between sunlight exposure and chlorine

degradation.2 The study also showed that as the sunlight intensity increased from winter









to summer months, the chlorine loss within the uncovered basin increases also. The

study provided some unexpected results: the total trihalomethane (TTHM) concentrations

were actually lower in the covered basin than the control, or uncovered basin.2 This

phenomenon is opposite of that found in the Pregeant1 study and is contrary to common

theory, where a higher residual produced a higher trihalomethane (THM) concentration.

One aspect of this study was to further investigate the phenomenon found by the IPPD

team.

In order to further ascertain the impact of solar radiation, ultraviolet (UV) and

visible radiation, on the chlorination process in the wastewater treatment plant, a research

plan was proposed to and accepted by the Gainesville Regional Utilities. One focus of

this study is the UV radiation catalysis of the oxidation reaction of water by chlorine to

form oxygen and the chloride ion, Equation 1-1. Also, this study reviews the impact of

UV radiation and global horizontal radiation on bacterial inactivation and disinfection by-

product (DBP) formation.

This study involves both a pilot and full-scale investigation of the chlorination

process at the KWRF to determine to what extent solar radiation affects chlorine residual,

disinfection effectiveness, and disinfection by-product formation.

Pilot Study

The pilot basin study involved two pilot basins scaled after the KWRF chlorine

contact basins. One basin was equipped with an opaque acrylic cover to block solar

radiation from entering and coming in contact with the water during chlorination. The

second basin was equipped with an UV transmitting clear acrylic, or UV-TRANS, cover

that allowed solar radiation, both UV and visible radiation, to come in contact with the

water during chlorination.









The feed water for the pilot basins had gone through the plant filters but was not

chlorinated by the plant chlorination system. The feed water to the pilot basins was first

dosed with a known concentration of chlorine (NaOC1), and then split into two equal

streams before entering the pilot basins.

The pilot basin study makes it possible to keep flow rate and chlorine dosage

constant which was not possible in the full-scale study. It also enabled the control and

variation of flow rates, pH levels, and chlorine dose to determine the extent of their

involvement in the effects of solar radiation on the chlorination process and water quality

parameters.

KWRF average, minimum, and maximum chlorine dosage, pH, and flow rates were

used in this phase of the study. The KWRF's effluent wastewater had a total chlorine

residual minimum of 1.4 mg/L as Cl2, an average of 2.8 mg/L as Cl2, and a maximum of

4.8 mg/L as Cl2 according to data provided by GRU for 2003. In the pilot study the

average plant value was used as the pilot baseline value while chlorine dosing that

produces water with minimum and maximum residual values was also tested. The

influent pH, or raw pH, experienced at the KWRF does not vary much from a neutral pH,

around 7. Thus, for this experiment a pH of 7 was used as the baseline value while pH

values of 6 and 8 were also tested to determine the influence of pH on the pilot system.

In the pilot study a baseline hydraulic retention time (HRT) of 2.75 h was used. A longer

HRT of 3.81 hrs was also tested to amplify the effect of radiation on water quality

parameters in this study. The KWRF average and maximum HRT in the chlorine contact

basins is approximately 1.8 and 4.4 h, respectively.









Full-Scale Study

A full-scale study was also implemented to further investigate the effect of solar

radiation on the disinfection chlorination stage of the wastewater treatment under normal

operating conditions. The full-scale study was performed on the North basin and did not

include the south basin.

In the North basin the flow is split immediately into two parallel streams after it

enters the basin. Chlorine gas is injected into the pipe that transfers the wastewater from

the post-aeration basin to the North chlorine contact basin. In the full-scale study one

half of the basin was covered with polypropylene tarps and the other half was left

uncovered. As in the pilot-scale study the effect of UV radiation on the chlorine residual,

disinfection effectiveness, and disinfection by-product formation was investigated. The

full-scale study was performed to determine the effect of covering the basin under

standard plant chlorination procedures so no special adjustments were made. Just as in

the pilot study, the UV radiation impact on chlorine residual, disinfection effectiveness,

and DBP formation was examined.

Clarifier Chlorine Addition

The KWRF has recently installed chlorine injection pipes in the clarifiers

(Figure 1-4). The chlorine addition was implemented to reduce algae growth in the weirs

of the clarifiers. The chlorine addition at the clarifiers, however, would also result in the

formation of DBP and could have a lingering effect on chlorine residual and demand.

This would lead to inaccuracies in data collected during the pilot and full-scale studies.

In order to prevent the interference caused by the chlorine dosing of the clarifiers the

chlorine dosing of the clarifiers was ceased at 4 pm the day prior to sampling and

remained turned off until 4 pm the day of the testing. Sampling and analysis of the pilot









basin feed wastewater indicated that ceasing the addition of chlorine in the clarifiers at

4:00 pm ensured that the chlorine residual and TTHM concentrations were below

detection at 9:00 am the next morning.




















Figure 1-4. Chlorine addition at the clarifiers.














CHAPTER 2
REVIEW OF LITERATURE

Nitrification/Denitrification

Nitrogen is incorporated into all living things, and is also present in the atmosphere.

Nitrogen is taken from the atmosphere by nitrogen-fixing bacteria and through the action

of electrical discharge during storms.3'4 Although nitrogen is necessary for life, if too

much nitrogen is fed into a receiving body of water an over production of algae and other

aquatic life can occur, or eutrophication.4'5 Also, organic nitrogen compounds and

ammonia exert a chlorine demand. A higher chlorine dose would be required to achieve

adequate disinfection if organic nitrogen and ammonia were not removed prior to

disinfection.6 Domestic raw wastewater contains mostly organic and ammonia nitrogen,

or Kjeldahl nitrogen.5

One of the major treatment processes at the KWRF is the use of biological

nitrification and denitrification to remove nitrogen from the wastewater. The autotrophic

nitrifying bacteria group, Nitrosomonas, under aerobic conditions oxidizes ammonia and

ammonium to form nitrite (Equation 2-1).3,4,5,7 Nitrite can then be oxidized further by the

bacteria group Nitrobacter to form nitrate (Equation 2-2).3,4,5,7 The aerobic oxidation of

organic nitrogen to inorganic nitrogen, nitrification, is carried out in the aeration basins

and also in the newly installed carousel at the KWRF.

2NH3 + 302 Ntrosmonas >2NO2 +2H20 + 4H (2-1)

2NO2 +02 Ntrobacter > 2NO3 (2-2)









After the ammonia and ammonium are converted to nitrite and nitrate it can be

reduced to nitrogen gas by facultative anaerobic bacteria, such as Pseudmonas.3'5'7 It is

presumed that any nitrate present is reduced to nitrite and then to nitrogen gas. The

overall denitrification is shown in (Equation 2-3). At the KWRF the reduction of nitrite

and nitrate to nitrogen gas, denitrification, takes place in the anoxic basins and in the

newly installed carousel.



6NO3 + 5CHOH bactena >3N2 + 5CO + 7H2 + 6(OH) (2-3)



Chlorine Disinfection

Disinfection of wastewater can be dated back to the late 1800s with the use of

chlorinated lime for odor control and the treatment of fecal material from hospitals.8

Because of the known health problems inflicted on humans by microbial organisms,

disinfection of wastewater has become a mainstream procedure. The disinfection of

wastewater helps prevent bacterial contamination of drinking water sources, thus, aiding

in the control of waterborne diseases. Chlorine is one of the most widely used

disinfectants for both potable and wastewater treatment because of its relatively low cost

and effectiveness as a disinfectant when compared to other alternatives.6'8 At

atmospheric pressure and room temperature chlorine exists as a poisonous yellow gas.8

For the purpose of water and wastewater treatment chlorine gas is pressurized as a dry,

liquefied gas and is stored in steel cylinders to make it easier to store and apply. During

chlorine disinfection three types of reactions can occur: oxidation, addition, and

substitution.9











Free Chlorine

In wastewater the chlorine gas is added to water and hydrolyzes to hypochlorus

acid (HOC1) and the hypochlorite ion (OC-) (Equations 2-4 and 2-5).4,6,7 Together,

HOC1 and OC1- are called free chlorine.


Cl2 + H20 HOCI + H + Cl (2-4)


HOCI OCl + H (2-5)

Studies show HOC1 to be a more efficient disinfectant and a stronger oxidant than

OC1- hence HOC1 is the desired species when disinfecting.8'10 The pKa for HOC1 is 7.5at

25C, thus, at a pH of 7.5 HOC1 and OC1- exist in equal concentrations. If the pH is

below 7.5 the predominant species is HOC1 while at a pH above 7.5 OC1 predominates.4

The percentage of free chlorine as HOC1 and OC1- is dependent on the pH and


temperature conditions (Figure 2-1).4 Most wastewater treatment facilities operate in a

range where the HOC1 species is prevalent thus increasing their disinfection efficiency

and lowering the chlorine dose required to achieve disinfection.6

100 1 -- ^-------- -,,,



3" ----- + -------- 1 20
00 r 0
60

40
60 -------------- 40

S 50 500

40 60
20'C
r 2hi----- iO170





73 A DO3
pH

Figure 2-1. Percent of free chlorine compound (HOC1 and OC1-) versus pH.









Chlorine can react with many chemicals, inorganic and organic, present in the

wastewater stream. The amount of chlorine dissipated during these reactions is referred

to as the chlorine demand the wastewater possesses and dictate the amount of chlorine

that must be added to achieve a specific chlorine residual and good disinfection.

Combined Chlorine

In the presence of ammonia (NH3) the free chlorine species HOC1 will react to form

chloramines that consist of monochlroamine (NH2C1), dichloriamine (NHC12), and

nitrogen trichloride (NC13).4,6,10 (Equations 2-6, 2-7, and 2-8).


NH3 + HOC -> NHCl + H20 (2-6)


NH2Cl + HOCI NHCl, + H20 (2-7)


NHCl, + HOCl NCl3 + H20 (2-8)



Chloramines have the capacity to disinfect wastewater but are not as effective as

free chlorine. All domestic wastewaters contain organic nitrogen compounds, including

amino acids and proteins.6'8 Chlorine reacts with these organic nitrogen compounds to

form organic chloramines. Though these organic chloramines contribute to the combined

chlorine concentration they have no known disinfecting capability.6'8 Organic

chloramines show up as combined chlorine in the iodometric and DPD chlorine residual

methods.8 The speciation of inorganic chloramines is more related to the pH of the

wastewater and the chlorine to ammonia molar ratio and not as much on the contact time

of ammonia and HOC1.6'8 Under normal operating conditions monochloramine

predominates. As the pH decreases below neutral (pH=7) and as the C12:N mass ratio









value increases from 3:1 up to 7:1 the formation of dichloramine is favored. As the pH

-- 6
continues to decrease nitrogen trichloride will form.6

The chloramine hydrolysis reactions will result in the release of ammonia, which

could play a role in nitrification (i.e. formation ofNOs3). The decomposition of

dichloramine increases as the pH and alkalinity increase.6'8 This makes dichloramine less

stable than monochloramine under normal wastewater conditions. The decomposition of

monochloramine occurs in essentially two reactions the first being hydrolysis and the

following being the acid catalyzed reaction with the generated free chlorine and results in

the formation of dichloramine and ammonia in the wastewater.6'8


Break-Point Chlorination

In order to form HOC1 in the presence of ammonia or other organic nitrogen

enough Cl2 gas must be added to reach and pass what is called the breakpoint

(Figure 2-2).4 The process is therefore termed breakpoint chlorination. Beyond the

breakpoint free chlorine is dominant and makes up a large percentage of the total

chlorine. However, also present beyond the breakpoint are what are termed "irreducible"

or "nuisance" chlorine residuals that show up in total chlorine residual measurements but

do not have the disinfecting capabilities that free chlorine possesses.6 The organic

chloramines and, if present, nitrogen trichloride contribute to the irreducible chlorine

residual.







14


Mole roti, C2:NH3- N
0.5 ,0 1.5



to


8 c

7


4 5



BreOH point
2
Free chlorine
SCombined chlorine residual
residuoas in predom;nonce predominoni

1 2 3 4 5 6 7 8 9 10 11
Chlorine dosage, rg/liter

Figure 2-2. Breakpoint chlorination: Species of chlorine residuals present during
chlorination when ammonia is present.

Compounds other than ammonia and organic nitrogen compounds can exert a

chlorine demand; the demand exerted is related to their concentration in the wastewater.

For example, inorganic substances such as the sulfide, sulfite, nitrite, iron (II), and

manganese (II) ions all can exert a chlorine demand.8 If ammonia is present in the

wastewater stream the demand these species exert is reduced and sometimes even

eliminated.8

Contact Time

One of the most important parameters in chlorine disinfection is contact time.

Inactivation of pathogens increases with an increase in contact time. The disinfection

effectiveness is expressed as Ct; where C is the disinfectant concentration, and t is the

contact time necessary to inactivate the desirable amount of the pathogenic organism.3'7

In essence, the longer the provided contact time, the subsequently less chlorine is









necessary to achieve sufficient disinfection. Based on a comprehensive pilot plant study

Collins et al. developed an equation to determine bacterial inactivation at wastewater

treatment plants (Equation 2-9).6 The equation fits best where good initial mixing

followed by plug flow conditions occur. The wastewater at the KWRF is first filtered

prior to chlorine disinfection. Accordingly, the initial bacterial concentration would

probably range from 3,000 to 10,000 coliforms per 100 mL.6


y = yo[+ 0.23. ct]3 (2-9)
yo = initial bacterial concentration prior to chlorination
y = bacterial concentration at end of contact chamber or at time T in minutes
c = initial chlorine concentration
t = contact time in minutes


The model can be used to predict bacterial inactivation in wastewater given the

HRT provided in the disinfection chamber. As the model demonstrates, the disinfection

of wastewater with chlorine depends greatly on chlorine concentration addition as well as

contact time. The KWRF uses chlorine contact basins, described earlier, to provide the

contact time necessary to inactivate the indicator organisms, total and fecal coliforms.

As wastewater chlorine demand changes the chlorine addition is altered to provide

adequate disinfection.

Disinfection By-Product Formation

Though the chlorination of wastewater is beneficial in inactivating disease-causing

organisms it can also cause the formation of potentially harmful and carcinogenic

compounds. According to epidemiological studies there is a correlation between water

chlorination and rectal and bladder cancer cases.1l When organic compounds or

precursors such as natural organic matter (NOM), humic and fulvic acids, are present










during chlorination they may react with the free chlorine to form what are collectively

called disinfection-by-products (DBPs).4

The main concern for public health surrounds the formation of DBPs known as

trihalomethanes (THMs) and haloacetic acids (HAAs). Because of the public health

concern surrounding these compounds, the federal Environmental Protection Agency

(EPA) has imposed a maximum concentration allowed in drinking water. As of 2004 the

regulatory drinking water MCL standards for TTHM and HAA(5) are 80 [tg/L and 60

[tg/L, respectively.12 THM species include chloroform (CHC13), a known human

carcinogen, bromoform (CHBr3), bromodichlormethane (CHBrC12), and

dibromochlormethane (CHBr2C1) (Figure 2-3). The five HAA species that are currently

under regulation include monochloroacetic acid (MCAA), monobromoacetic acid

(MBAA), dichloroacetic acid (DCAA), dibromoacetic acid (DBAA), and trichloroacetic

acid (TCAA) (Figure 2-4).8 13 There are several factors that can affect the formation of

these DBPs, such as, temperature, pH, precursor concentration, chlorine dose, contact

time, and bromide concentration.

Cl Br
I I
H C Cl H C- Br
I I
Cl Br
Chloroform Bromoform

Cl Cr
I I
H --C- Cl H -C- Br
I I
Br Br

Bromodichloromethane Dibromochloromethane

Figure 2-3. The THM species.











Cl 0 Br 0

I II I II
H C C OH H C C OH

H H

Monochloroacetic acid Monobromoacetic acid
(MCAA) (MBAA)

Cl O Br O

I II I II
Cl _C C OH Br C C OH

H H

Dichloroacetic acid Dibromoacetic acid
(DCAA) (DBAA)


Cl O

I II
Cl _C C OH

Cl

Trichloroacetic acid
(TCAA)

Figure 2-4. The HAA(5) species.

The natural organic matter (NOM) present in wastewater is a precursor for DBPs

during chlorination.1 The NOM is measured as dissolved organic carbon (DOC) or total

organic carbon (TOC). NOM consists largely of aromatic compounds, thus, studies have

found that aromaticity was a good surrogate for the prediction of DBP formation.14'15 In

general, as the NOM concentration increases the DBP formation during chlorination also

increases. This increase in DBP formation is the result of an increase in these DBP

precursors but also is due to the increase in chlorine demand exerted by the NOM.11

With the increase in chlorine demand a higher chlorine dose is necessary to maintain the

required chlorine residual. The increase in chlorine dose will result in an increase in DBP

formation. In one study, lower molecular weight NOM compounds resulted in a higher









total trihalomethane (TTHM) yield.16 In general, as the molecular weight of the NOM

present in the water or wastewater decreased the TTHM yield increased.16 In one study,

findings showed that when chlorine is applied to water containing NOM the hydrophobic

NOM fraction resulted in a higher DBP formation than the equivalent hydrophilic

fraction.17 Through the oxidation of NOM with chlorine intermediate compounds may

form."1 These intermediates are further oxidized by chlorine, or bromine, to form DBPs.

Generally, as precursor concentration, NOM, increases so does the DBP production, but

it will tend to plateau and even decline after the residual chlorine is exhausted.1 The

apparent decrease in THM production shown in the study done by Pregeant et al. which

was carried out at high precursor concentrations was hypothesized to result from the

predominance of THM intermediates when excess precursors existed.1 The reactions that

result in the direct formation of DBP tend to occur more quickly and form earlier during

the chlorination process than those that have an intermediate step."

Environmental factors such as bromide concentration and the amount of natural

organic matter affect the amount of DBPs formed during chlorination. Chlorine oxidizes

the bromide ion forming hypobromous acid (HOBr) and hyprobromite (OBr-) ion,

depending on the pH.18 The hypobromous acid and, to a lesser extent, the hypobromite

ion react with DBP precursors by oxidation and substitution reactions to form brominated

DBPs.11,18 As the bromide concentration increases the chlorinated HAA concentration

decreases.18 Given the same chlorine dosing, the addition of the bromide ion results in an

increase in the HAA concentration. Studies have also shown that the hypobromous acid

oxidizes NOM more readily than hypochlorous acid.11,18,19 In one study it was

determined that bromine reacted ten times faster with NOM isolates than chlorine.19 The









presence of the bromide ion (Br-) in the wastewater stream can greatly alter the speciation

and formation of THM and HAA during chlorination.18 The free chlorine oxidizes the

Br- to hypobromous acid (HOBr) (Equation 2-10); HOBr will ionize as the pH increases

to OBr-.


HOCI + Br HOBr + Cl (2-10)


The bromide ion can have a substantial effect on the mass concentration of DBP as

bromine has a greater molecular weight, 80, than chlorine, 35.5. The DBPs formed when

HOBr reacts with organic precursors have a higher molecular weight than those with

chlorine. This is a concern as the EPA MCLs for DBP are on a mass basis, ug/L, and

not a molar basis.

As the temperature of the wastewater increases so does the HAA and THM

concentrations. The pH has a variable effect on the DBP concentration. Studies have

found that as the pH is increased from 6 to 8, the THM formation also increased but

resulted in a lower HAA formation.11,17,20 When the pH is lowered from a neutral pH to 6

the HAA formation increased.11'17

A longer chlorine contact time will result in a higher DBP formation because more

time is allowed for chlorine to react with NOM. An increase in contact time will allow

those reactions that require intermediate steps more time to react to completion. The

formation of THM increases as time allowed for reaction with free chlorine increases, or

the contact time, though the rate of formation is not constant. The chlorine dose has a

similar effect on DBP formation as the dose increases so does the DBP concentration









sometimes reaching a plateau.1 The chlorine dose can also affect the speciation of DBP as

the dose increases the ratio of THM to total halogenated DBP ratio also increases.

Modeling of DBP formation. Disinfection by-product formation modeling helps

to predict the amount of DBP formed during the chlorination of a feed water if the

necessary parameters are known. The EPA has developed disinfection/disinfection by-

product rule models to predict THM and HAA formation to determine operational and

economic impacts of setting new MCLs.13 The models used to predict THMs were

developed by Malcome Pirnie and models used to predict HAAs were developed by Dr.

Charles Haas, contracted by the AWWA D/DBP Technical Advisory Workgroup

(TAW).13 Since the KWRF provides tertiary wastewater treatment where additional

solids are removed by the six media filters the EPA models developed for drinking water

are applicable..

AWWA contracted Montgomery Watson to develop new model equations for

individual THM and HAA species and published the findings in a March 1993 report.13

Environmental parameters used in the formation of the model equations include bromide

concentration, TOC, ultraviolet light absorbance at 254 nm, temperature, chlorine dose,

pH, and reaction time. Using the basic equation (Equation 2-11)13, as a guideline the

coefficients for each environmental variable were determined through a step-wise

regression model procedure for individual THM and HAA species.


DBP = k (TOC)a (pH)b (TEMP) (CL2DOSE)d (BR)e (UV 254) (TIME)g (2-11)


k, a, b, c, d, e, f, and g are empirical constants









The program STATVIE\\' was used in the step-wise regression procedure to determine

the coefficients. Another study showed that if the data is available nitrate, calcium, and

alkalinity could be used in the prediction of THM formation.21

Chloroform made up the majority of the TTHM concentrations in this study and

thus the AWWA model equation for chloroform (Equation 2-12) 13 was used to normalize

the sampling sets; an explanation of the normalization method used is in the Materials

and Methods section.


CHCl3 = 0.064[TOC] 329 pH1 161T1 018[C2Dose]0 561 [Br + 0.01]0 404 8740 269 (2-12)

CHCl3 =g / L
T = Temperature(C)
t = Time(hrs)
TOC =mg/L
Cl2Dose =mgL -Cl2
Br 1 = mg/L
UV254 = cm


The model predicted chloroform concentration is plotted versus the observed

chloroform concentration for the whole model development database from the March

1993 AWWA report (Figure 2-5).13 A perfect prediction would result in a slope of 1, the

farther from the perfect prediction line the less accurate the prediction.13 The prediction

versus the actual chloroform coincides better from 0 to 200 tg/L than concentrations

greater than 200 [tg/L. Typical wastewater TTHM concentrations do not exceed

200 ag/L.13










1000


800 -


S * Sope 1
o/


0 600 *

"s Slope I


S200 '."





0 200 400 600 800 1000

Observed Concentration (pg/L)

Figure 2-5. Predicted versus the observed concentration of CHC13 for the entire model
development database from the 1993 AWWA report.

The AWWA model equation for dichloroacetic acid (DCAA) was used to

normalize HAA(5) concentrations of the sampling sets, an explanation of the

normalization method is in the Materials and Methods section. The relationship of the

variable environmental parameters in the formation of the HAA(5) species DCAA is

shown in (Equation 2-13).13


DCAA = 0.605[TOC]0 291 [Temp ]0 665 [Cl2Dose]o04so [Br + 0.01] -0 568 0 239 [UV 254]0 726 (2-13)

DCAA = g / L
t = Time(hrs)
TOC =mg/L
Cl Dose = mg /L C2
Br 1 = mg/L
Temp="C









The model predicted DCAA concentration was plotted versus the observed DCAA

concentration for the whole model development database from the March 1993 AWWA

report (Figure 2-6).13 The predicted concentrations do not correlate perfectly with the

observed values, however, the points lie close to the perfect prediction line, slope =1, and

is sufficiently accurate.13

300

















0 100 200 300
t 200datb Sope











0 100 200 300

Observed Concentration (Jg/L)


Figure 2-6. Predicted versus the observed concentration of DCAA for the entire model
development database from the 1993 AWWA report.

Sunlight/UV Irradiation

At the KWRF, chlorine disinfection of wastewater occurs in an open flow-through

basin. This allows sunlight to come in contact with the chlorinated water. Aqueous

chlorine is unstable when exposed to sunlight, which results in the degradation of free

chlorine within the wastewater stream (Equation 2-14).

2HOCI 2H + 2Cl + 02 (2-14)









The cost of this loss can add up since more chlorine is needed to achieve the

desired disinfection. In the 2002 IPPD study the chlorine residual was substantially

greater in a covered basin versus an exposed basin given the same initial chlorine dose

and contact time.10 The amount of chlorine loss to solar irradiation depends on the length

of exposure and the volume of wastewater irradiated, which in turn depends on the angle

of incidence between the sun and chlorine contact basin and the turbidity. In most cases

the photodecay of HOCl is assumed to follow a first-order reaction.22

The ultraviolet (UV) radiation degrades chlorine and is that portion of the

electromagnetic spectrum between wavelengths of 100 and 400 nm. UV radiation is then

divided into vacuum UV (100-200 nm), UV-C (200-280 nm), UV-B (280-320 nm), and

UV-A (320-400 nm).22

The transmittance of solar radiation through a medium is dependent on several

factors including the type (e.g. glass) and thickness of the medium, the angle of

incidence, and the specific wavelength or bands of radiation. Pyrex glass (borosilicate

type), is opaque to UV-B radiation and has maximum transmission at 340 nm and higher,

this is the UV-A portion of the spectrum.22 Plastics, such as, polystyrene (i.e. Lucite) and

methylmethacylate (i.e. Plexiglass) can have a higher radiation transmittance than glass at

wavelengths greater than 290 nm. Thus, these plastic materials have greater transmission

of germicidal solar radiation at wavelengths from 300 to 400 nm.22 In this study an

acrylic UV-transparent plastic was used as it allowed solar radiation, UV and global, to

come in contact with the wastewater during chlorination and was cost effective.

The sunlight inactivation of microorganisms in water and wastewater is

proportional to the sunlight intensity, contact surface area, and atmospheric temperature









and is inversely proportional to water depth.23'24'25 Sunlight inactivation, or disinfection,

is also dependant on the bacterial contamination load of the water, the more bacteria to

inactivate the longer the necessary exposure time.24 Turbidity and color also play a big

role in the inactivation of microorganisms through sunlight exposure.24'25 In one study, it

was reported that turbidity inversely affected the kill rate for all bacteria tested.23 In

general, a higher turbidity will require a longer sunlight exposure to obtain adequate

disinfection.23

Besides the inactivation of microorganisms, absorption of sunlight also tends to

increase the temperature of the exposed water. At higher water temperatures, greater

than 700C, the bacterial inactivation is greater than at lower water temperatures, less than

65 0C.25,26 Studies have determined through the implementation of dark experiments

runs, chlorine dosing experiments that are performed with no sunlight exposure, that solar

radiation was the primary disinfecting factor when the water temperature was 9 to

26C.27,28 According to sensitivity studies, fecal coliform were the most sensitive

microorganisms to sunlight inactivation among those microorganism tested, such as,

somatic coliphages and bacteriaphages.26'28'29

One concern of covering the chlorination basin is the removal of the natural

disinfecting property of sunlight. Though the chlorine dose will be higher in the covered

basin this may or may not coincide with higher coliform inactivation as the contribution

of sunlight to the wastewater disinfection process has yet to be quantified. The extent

sunlight will affect the chlorination process depends on how much sunlight reaches the

water in the basin. The different wavelengths within the sunlight spectrum have different

coliform inactivation potentials. As explained in Acra et al. the inactivation of coliform









bacteria decreases exponentially as the wavelength of light increases from 260 nm to 850

nm.22 Thus, the destruction of coliforms, and expectantly other bacteria too, is most

efficient at the lower wavelengths (260 nm to 350 nm), and is least efficient at the higher

wavelengths (550 nm to 850 nm). Thus, the UV-B and UV-A portions of the spectrum

possess the greatest inactivation potential.22

Wavelengths below 290 nm should not be included when considering solar

radiation, as they do not reach the surface.22 This phenomenon is due to diffusion, or

scattering, and absorption of light before it reaches the surface.22 The solar UV-A

intensity changes as the Earth's angle of tilt changes. The highest intensity of UV-A

occurs during the summer months while the peak maximum and minimum occur at the

summer and winter solstice, respectively.22 Thus, the inactivation of coliforms by

sunlight is greater during the summer months. Also, chlorine loss is expected to be

highest during the summer as the degradation of chlorine is catalyzed by UV light.














CHAPTER 3
MATERIALS AND METHODS

Measured Parameters

Global Solar Radiation

Global solar radiation, or light, between 285 and 2800 nm wavelength was

measured using a Black and White Pyranometer (8-48) manufactured by Eppley

Laboratory, Newport, Rhode Island.


Ultraviolet Radiation

Ultraviolet radiation with a wavelength of 295 to 385 nm was measured using a

Total Ultraviolet Radiometer (TUVR) manufactured by Eppley Laboratory, Newport,

Rhode Island.

The radiometer and pyranometer were located on location at the KWRF

approximately 0.5 m from the pilot basin system. Radiation measurements for both

instruments were recorded every 5 minutes throughout the pilot and full-scale runs. The

millivolt outputs from the pyranometer and radiometer were stored in a Campbell

Scientific CR510 datalogger. The datalogger was powered using the Campbell Scientific

PS100 Power Supply and Charging Regulator. Using the Campbell Scientific SC32B

Optically Isolated RS-232 interface the data were transferred from the datalogger to the

laptop computer for analysis. The radiometer, pyranometer, and datalogger setup is

shown in (Figure 3-1).


















CR510 Datalogger










Figure 3-1. Radiometer, pyranometer, and datalogger setup.

Total and Free Chlorine Residual

Both total and free chlorine residual were measured in the inlet and effluent

samples for the pilot and full-scale experiments. The DPD method was used with the

HACH DR 2000 Spectrophotometer to determine total and free chlorine residual in the

field. The method was equivalent to the US EPA 330.5 method for wastewater, standard

method 8167 for total chlorine and standard method 8021 for free chlorine residual. A

sample of wastewater was collected from the respective sampling area and diluted using

deionized water when necessary. According to a chlorine residual test performed on June

10, 2004 the deionized water resulted in no chlorine residual addition nor a chlorine

demand.

The HACH DR 2000 spectrophotometer wavelength calibration was performed on

June 10, 2004 and again on August 6, 2004. In both calibration events the wavelength

did not need to be adjusted demonstrating that the spectrophotometer was still in line and









was giving accurate readings. A chlorine residual calibration was also preformed on

those days, using chlorine free glassware, by comparing the residual concentration

reading from the DR2000 field spectrophotometer to that of the lab HACH DR2010

spectrophotometer, no difference was observed between the two readings.

Total Suspended Solids


The KWRF lab uses EPA method 160.2 to measure the total suspended solid

concentrations in the effluent wastewater samples. Samples were taken from the inlet

and the two effluents for the pilot and full-scale studies. Plastic one-gallon containers

were used in the collection of samples for the total suspended solids analysis. Directly

after collection the samples were taken to the KWRF lab and refrigerated until analyzed,

the time between collection and placement in the refrigerator did not exceed 15 minutes.

Total Coliform

The KWRF lab uses Standard Method 9222B to analyze the wastewater samples to

determine the total coliform population of the samples. Total coliform counts were

measured in lieu of fecal coliform since fecal coliform are more easily inactivated than

other species that make up total coliforms. Fecal coliform are also more easily damaged

by UV radiation than other total coliform species. Samples were taken from the inlet and

the two effluents for the pilot and full-scale studies. Glass 1 L Whatman containers and

100 mL plastic containers, for pilot basin inlet samples (pre-chlorination), were

autoclaved and supplied by the KWRF lab and used in the collection of wastewater

samples for the total coliform analysis. Directly after collection the samples were taken

to the KWRF lab and refrigerated until analyzed, the time between collection and

placement in the refrigerator did not exceed 15 minutes.









Trihalomethane (THM)

The THM speciation and concentration was determined following the EPA Method

624, method for organic chemical analysis of municipal and industrial waste.30 Dr. M.

Booth performed the THM sample analyses at the University of Florida, Department of

Environmental Engineering and Sciences Analytical Sciences Lab (ASL). The following

materials were used in the sampling stage of the THM analysis:

* 40 mL amber glass VOA sampling vials
* Teflon septa
* Sodium Thiosulfate, to quench chlorine residual
* Tekmar 3100 Purge-and-Trap Concentrator
* Finnigan Trace 2000 GC/MS
* Gas-Chromatograph: Restek Rtx-VMS capillary column, 30m x 0.32 mm I.D.,
1.8 jtm film thickness
* Mass Spectrometer: Electron Ionization, 34 amu to 280 amu in 0.4 seconds


Sample GC/MS curves as well as THM analysis conditions can be found in

Appendix G. For the pilot basin system the THM samples were collected at the effluent.

Both the inlet and effluent samples were collected for the full-scale system. The samples

were stored on ice directly after collection and transferred to the ASL for analysis at the

end of each sampling day. The samples were then stored in the lab refrigerator until they

were analyzed. In all instances, the samples were analyzed within the suggested holding

period.

Haloacetic Acid (HAA)

The HAA speciation and concentration was determined following the EPA Method

552.2, determination of haloacetic acid and dalapon in drinking water by liquid-liquid

extraction, derivation and gas chromatography with electron capture detection.31 The

derivation and methylation of the HAA samples were performed at the University of









Florida ASL. The following materials were used in the sampling stage of the HAA

analysis:

* 40 mL amber glass VOA sampling vials
* Teflon septa
* Ammonium Chloride, to quench chlorine residual
* Hewlett-Packard 5890 Series II GC/ECD
* Gas-Chromatograph: Restek DB5MS Capillary Column, 30m x 0.25 mm I.D., 0.25
um film thickness

Sample GC/ECD curves as well as HAA analysis conditions can be found in

Appendix G. For the pilot basin system the HAA samples were collected at the effluent.

Both the inlet and effluent samples were collected for the full-scale system. The samples

were stored on ice directly after collection and transferred to the ASL for analysis at the

end of each sampling day. The samples were then stored in the lab refrigerator until they

were analyzed. The methylation procedure was performed within 3 days of sample

collection, well within the suggested holding time. Dr. M. Booth then analyzed the

methylated samples within the suggested holding period.

pH

The pH of the feed and effluent streams for the pilot and full-scale studies was

measured using the Orion model 290A pH meter with the 9157BN-thermo temperature

compensating probe. Every morning, prior to sampling, the pH meter was calibrated

using 3-point calibration with pH buffer solutions 4, 7, and 10.

Conductivity

The conductivity of the feed and effluent streams for the pilot and full-scale studies

was measured using the Fisher Scientific 09-328 Automatic Temperature Compensation

Conductivity probe. The conductivity probe meter was calibrated every morning using a

0.01 N KC1 solution.









Dissolved Oxygen

The dissolved oxygen (DO) of the feed and effluent streams for the pilot and full-

scale studies was measured using the YSI Dissolved Oxygen/Temperature Meter (YSI

Model 57/ YSI 5739). Every morning the probe was checked for air bubbles from

membrane weakening. If air bubbles were present then the probe solution and membrane

were replaced.

Sampling

Wastewater sampling from the respective location (i.e. inlet or effluent in the pilot

or full-scale system) and parameter was collected in a manor to limit aeration while also

obtaining a good representative sample. The parameters that were analyzed by the

KWRF lab, TSS and total coliform, were stored in the lab refrigerator directly after a

sampling. The KWRF samples were put in the refrigerator within 15 minutes of

collection. Those samples that were analyzed at the University of Florida Department of

Environmental Engineering and Sciences ASL, THM and HAA, were stored on ice after

collection and then transported to the lab after the last sample of the day was collected.

The samples were then transferred to a refrigerator located in the ASL where they were

then analyzed using their respective method.

Pilot Scale System

The plant chlorine contact basins, North and South, (Table 3-1) are setup in series

where the wastewater first flows through the smaller and older North basin and then

through the larger South basin before it is finally deep well injected, used as reclaimed

water, or sent to the emergency holding pond. Each pilot basin (Table 3-2) was designed

to simulate the hydraulic retention time (HRT), flow pattern, and dimension ratios

through both the North and South chlorine contact basins. For example, the length to









width ratios seen in the two full-scale basins were averaged and used in the pilot basin

design. Full calculations can be found in Appendix A.

Table 3-1. Chlorine contact basin dimension ratios.
South CCB North CCB Pilot basin
L:W 1.2 L:W 1.0 L:W 1.1
L:H 6.3 L:H 5.3 L:H 5.8
W:H 5.2 W:H 5.3 W:H 5.3
C:W 0.1 C:W 0.1 C:W 0.1
No. of channels 8 No. of channels 10 No. of channels 9
L: Length, H: Height, W: Width, C: Channel Width

Table 3-2: Pilot chlorine contact basin dimension.
Pilot basin dimensions
Length (ft) 4.0
Width (ft) 3.7
Height (ft) 0.7
No. channels 9


One basin was equipped with an opaque acrylic cover to block solar radiation from

entering and coming in contact with the wastewater during the disinfection step of the

treatment process. The second basin was equipped with an UV transmitting clear acrylic,

or UV-TRANS, cover that will allow solar radiation, both UV and visible radiation, to

come in contact with the wastewater during disinfection. Thus, the basin with the UV

radiation transparent cover was termed the TRANS basin and the basin that prevented

UV and solar radiation exposure of the wastewater during the disinfection stage of

treatment was termed the OPAQ basin.

Each basin had one inlet and one outlet that have /4 inch brass barbs, which allows

for the connection of the 14 inch plastic tubing. The Analytical Research Systems Inc.

located in Micanopy, Florida constructed the basins to specifications presented to them.

A fluoroscein tracer analysis was performed on one of the basins to determine the flow









pattern of the pilot basins. It was determined that each pilot basin modeled as 41 tanks-

in-series with a tio value of 61 minutes. The tracer analysis was performed with a flow

rate of 42 GPH, a HRT of 107 minutes, the full calculations are shown in Appendix B.

The feed water for the basins had gone through the plant filters but not the chlorine

contact basin. The feed water to the pilot basins was first dosed with a known

concentration of chlorine (NaOC1), and then split into two equal streams before entering

the pilot basins. The chlorine solution preparation is explained in the Chlorine Dosing

section. The chlorine solution was stored in a Nalgene container and added to the pilot

process using a Cole-Palmer Variable Speed Economy Driver pump with an Easy Load

LC-07518-60 head. A second pump and pump head was available for acid or base

addition for some experimental runs, again stored in a Nalgene container and added to the

pilot process using a Cole-Palmer Variable Speed Economy Driver pump with an Easy

Load LC-07518-60 head. Two static mixers were in place to give adequate mixing.

Flowmeters were in place on both basins to ensure steady and equal flow rates. The pilot

scale setup schematic and photographs of the system setup are shown in (Figure 3-2 and

Figure 3-3), respectively.

Wastewater Feed System Materials

* Tygon tubing
S1/2 inch ID
o 1/4 inch ID
* Static mixer, OD 5/ inch, ID 12 inch
* Barbed male pipe NPT connectors:
o Thread 1/s inch, tube ID 1/16, clear polypropylene
o Thread /4 inch, tube ID 1/4, natural polypropylene
o Thread /4 inch, tube ID 1/2, natural polypropylene
* Female tee, pipe size 14 inch, PFA
* Female reducer, NPT(F) x NPT(F): /4 x /s inch, PVC
* Barbed connector, 1/16 1/16 inch, Clear Polypropylene


































Acid
Pump


TRANS Basin OPAQ Basin

Figure 3-2. Pilot basin system setup.































Figure 3-3. Pilot scale setup; chlorine and acid/base solution containers, solution pumps,
influent water spigot, static mixers, t-split, TRANS and OPAQ basins.

Ten pilot-scale runs were performed at the KWRF. The experimental matrix was

as follows:

* 3 baseline runs
o HRT = 2.75 h
o Chlorine dose = 7.5-8.0 mg/L Cl2
o pH = no acid/base adjustment
* 3 low flow runs
o 2 low flow runs/average chlorine dose
HRT = 3.81 hours
Chlorine dose = 9-12 mg/L Cl2
pH=No acid or base adjustment
o 1 low flow run/high chlorine dose
HRT = 3.81 h
Chlorine dose = 16 mg/L Cl2
pH = no acid or base adjustment
* 1 high chlorine residual
o HRT = 2.75 h
o Chlorine dose = 8.2 mg/L Cl2
o pH= no acid or base adjustment









* 1 low chlorine residual
o HRT = 2.75 h
o Chlorine dose = 6.5 mg/L Cl2
o pH= no acid or base adjustment
* 1 low pH
o HRT = 2.75 h
o Chlorine dose = 7 mg/L Cl2
o pH = increased pH (H2S04 addition) effluent average = 6
* 1 high pH
o HRT = 2.75 h
o Chlorine dose = 7 mg/L Cl2
o pH= lowered pH (NaOH addition) effluent average = 9


Chlorine Dosing

Clorox bleach (NaOC1) was diluted in order to make the chlorine solutions for the

pilot scale study. The standard method lodometric method I, standard method 4500 Cl B,

was used to determine the total chlorine concentration in the concentrated Clorox

solution. The concentrated Clorox solution was then diluted with deionized water to

provide the desired concentration for dosing in the pilot basin experimental runs. Prior to

use the chlorine dosing solution concentration was measured to determine the actual

concentration. The full calculation for all of the chlorine solutions used to chlorinate the

pilot basins can be seen in Appendix C.

Pump Test

In order to determine the pump rate provided by the different settings on the Cole-

Palmer Variable Speed Economy Driver pump with an Easy Load LC-07518-60 head a

pump test was performed. The tube used in the system to provide solution dosing was

placed in a graduated cylinder filled with tap water. The beginning volume was recorded,

the pump was then set at a numbered position on the pump, the pump was started, and

then the volume was recorded after a certain time laps had occurred.









Full Scale

In the full-scale study the North basin was used since it was the first basin in the

series of the two chlorine contact basins and the wastewater had yet to be exposed to UV

radiation while containing chlorine. The influent wastewater was split at the inlet into

two parallel streams. The North basin is 58 ft long and 59 ft wide. A previous study at

the KWRF determined that the North and South basins together model as 60 tanks-in-

series while the North basin models as 100 tanks-in-series separately.2 One of the

parallel streams of the basin, 58 ft by 30 ft area, was covered with three polypropylene

tarps to prevent the wastewater from being exposed to UV radiation, the (COV) side.

The other side of the basin was left exposed to sunlight radiation, the (UNCOV) side

(Figure 3-4 (a)). The tarps were held down by concrete blocks (Figure 3-4 (b)), while

ropes were tide to rings located along the sides of the tarps. The ropes were then tied to

concrete blocks located on the ground along the sides of the basin. The concrete blocks

holding down the tarps were then removed. There were three full-scale experimental

runs performed for this study at the KWRF.












Figure 3-4. Full-scale setup. (a) Uncovered side of the basin. (b) Covered side of the
basin during the full-scale study.

The flow rates and chlorine dose for the full-scale study were the consequence of

the KWRF operation on the days of the study and were recorded by the operators in the









daily operations log. The daily operations logs were used to formulate the discharge

monitoring report (DMR) for the Department of Environmental Protection (DEP).

Sampling points in the post-aeration basin and North chlorine contact basin for the

full-scale study are shown in (Figure 3-5). The sampling points are as follows:

1. Post-aeration basin effluent; wastewater sample directly prior to chlorine injection

2. North chlorine contact basin inlet; where the wastewater first enters the basin and
directly prior to splitting into parallel flows

3. Covered side effluent; directly prior to recombination of parallel flows and the
South basin

4. Uncovered side effluent; directly prior to recombination of parallel flows and the
South basin


Figure 3-5. Sampling points in the post-aeration basin and North chlorine contact basin
for the full-scale study.









Calculations

Disinfection By-Product Data Normalization

To determine if other factors (i.e. UV and global radiation) are affecting the DBP

formation in the pilot and full-scale systems the TTHM and HAA(5) concentrations were

normalized to variable parameters (e.g. temperature) that are known to affect their

formation. Among the parameter differences, there was a definite temperature

differentiation between the TRANS and OPAQ basin in the pilot scale system and also

between the COV and UNCOV sides of the North chlorine contact basin in the full-scale

system resulting from absorption of radiation by the exposed wastewater. Temperature

data can be found in the discussion sections and also in Appendix E and F.

Trihalomethane normalization

To compensate for the difference in effluent conditions, such as, chlorine residual,

temperature, and pH the effluent TTHM concentrations were normalized. Normalization

factors for temperature, pH, and free chlorine residual were used to adjust the

concentrations. Since chloroform makes up the majority of the TTHM in every sampling

set, the modeling equation for coliform was used in the normalization of the THM

concentrations. (Equation 3-1) shows the relationship of chloroform formation to

temperature, pH, chlorine residual, and contact time. The model was taken from a March

1993 American Water Works Association report on modeling DBP formation during

chlorination at potable water treatment plants.13

CHCI, = 0.064[TOC]0 329 pH 1 161T1 18[Cl Dose] 561 [Br 1 + 0.01] 404 V 4874 269 (3-1)

CHC1, = gl/L TOC = mg/L UV254 = cm1
T = Temperature(C) Cl Dose = mg/ L- C12
t = Time(hrs) Br 1 = mg/L









In the normalization process the OPAQ basin and COV side effluent TTHM

concentrations were normalized to TRANS basin and UNCOV side effluent TTHM

concentrations, respectively. Normalization factors were calculated from parameter data

collected during each sampling run. The equation for each parameter normalization

factor was developed from Equation 3-1. Equations 3-2, 3-3, and 3-4 are the pH,

chlorine residual, and temperature normalization factor equations, respectively, for the

normalization of TTHM concentration of the OPAQ basin to the TTHM concentration of

the TRANS basin. The free chlorine residual was used in the normalization process. The

equations for the full-scale study were the same except the parameters of the COV and

UNCOV sides were used.

/1.161

pH Normalization Factor H= (3-2)
pHOPAQ

/ \0.561

Chlorine Residual Normalization Factor C (3-3)
C/OPAQ)

1 '.018

Temperature Normalization Factor = TTP 0 (3-4)
TOPAQ




In order to normalize the OPAQ basin, or COV side of the North basin, the effluent

TTHM concentration was multiplied by these normalization factors. The normalized

TRANS and OPAQ basin, or UNCOV and COV sides, TTHM concentrations were then

compared to determine if other parameters (i.e. solar radiation) had any influence on the

TTHM formation.









Haloacetic acid normalization

In order to compensate for the difference in effluent conditions (i.e., chlorine

residual) the effluent HAA concentrations were normalized. Normalization factors for

temperature and free chlorine residual were used to adjust the concentrations. Since

DCAA makes up the majority of the HAA(5) in the greatest number of sampling sets

compared with the other species the model equation for DCAA was used in the

normalization of the HAA(5) concentrations. Equation 3-5 shows the relationship of

DCAA formation to temperature and chlorine residual. The model was taken from a

March 1993 American Water Works Association report on DBP formation during

chlorination at potable water treatment plants.13


DCAA = 0.605[TOC ]0 291 [U -254]0726 [C 2Dose ]0 480 [Br 1 +0.01]0 568
(3-5)
[Temp ]0 665 to 239

DCAA =ug / L
Temp = Temperature(C)
t = Time(hrs)
TOC =mg/L
Cl2Dose =mg/L Cl
Br 1 = mg/L

In the normalization process the OPAQ basin and COV side effluent HAA(5)

concentrations were normalized to TRANS basin and UNCOV side effluent HAA(5)

concentrations, respectively. Normalization factors were calculated from parameter data

collected during each sampling run. The equation for each parameter normalization

factor was developed from Equation 3-5. Equations 3-6 and 3-7 are the temperature

and chlorine residual normalization factor equations, respectively, for the normalization

of HAA(5) concentration of the OPAQ basin to the HAA(5) concentration of the TRANS









basin. The free chlorine residual was used in the normalization process. The equations

for the full-scale study were the same except the parameters of the COV and UNCOV

sides were used.

/ A 0.665
Temperaturerwws
Temperature Residual Normalization Factor = Temperature I (3-6)



/ j 0.480
ClTRANS
Chlorine Residual Normalization Factor =-I (3-7)
y COPAQ


In order to normalize the OPAQ basin, or COV side of the North basin, the effluent

HAA(5) concentration was multiplied by these normalization factors. The normalized

TRANS and OPAQ basin, or UNCOV and COV sides, HAA(5) concentrations were then

compared to determine if other parameters (i.e. solar radiation) had any influence on the

HAA(5) formation.

Average Radiation

The average UV and global solar radiation exposure of the wastewater over the

HRT of the wastewater in the pilot basin was calculated for each sampling set. Equations

3-8 and 3-9 were used to calculate the UV and global solar radiation, respectively.

t=HRT

t=O
Average UV radiation (3-8)
HRT

UV= UV radiation readings taken every 5 minutes (mW/cm2)
t =minutes of retention time in the pilot basin
HRT=hydraulic retention time (min)









t=HRT
ZGSR
t=0
Average global solar radiation (3-9)
HRT

GSR=Global solar radiation reading taken every 5 minutes (mW/cm2)
t =minutes of retention time in the pilot basin
HRT=hydraulic retention time (min)

Standard Deviation

The standard deviation is a measure of how different values are from the average or

mean value (Equation 3-10).


STD = (3-10)
n(n 1)

STD = Standard Deviation n = number of arguments
x = value of argument (n)

Paired T-Test

The paired t-test was the statistical method used to determine if there were

statistical differences between sets of collected data from the pilot and full-scale studies.

The paired t-test is a variation of the standard t-test and is used to compare two treatment

methods where experiments are performed in pairs and the differences are of interest.

Since sample collection was performed in pairs in the pilot and full-scale studies and the

differences in the collected data sets are of interest, the paired t-test was appropriate to

use. The t*-value used in the paired t-test was calculated using Equation 3-11.

D-3
t*- (3-11)
SD
,n

t *= t value D = Mean difference
S= 0 SD = Standard deviation
n = number of samples









The t* values are then compared with the t-value for a given degree of freedom and

level of significance. If a t* value is greater than the t-value in the standard Student t

table, the difference is said to be significant to the degree found in the table.

Linear Correlation

In order to evaluate the linear correlation between two difference parameters the

one tailed t-test with the Pearson product moment correlation coefficient. The Pearson

Product momentum, r, varies between -1 and 1 and is unitless. An r-value of-1 and 1

represents a perfect negative and perfect positive correlation, respectively. The larger the

absolute value of the Pearson product momentum the stronger is the degree of linear

relationship between the two parameters. The Pearson Product momentum was

calculated using Equation 3-12.



r = (3-12)
S(X -Z y)2 x(Ly y )2



To determine if the linear correlation was significantly different from zero a

significance t-test was performed. First, two test hypothesis were established the first

being the null hypothesis, Ho, where the correlation is assumed to be zero. The second

hypothesis, Hi, assumes the other case where the correlation is greater than zero. The

one tailed t-test was used to determine which hypothesis was valid. The t* value used in

the correlation determination was calculated using Equation 3-13.


,t n (-2
t* = =r-2 (3-13)
1 HZ






46


If the calculated t* value was greater than the t critical value, tk, for a given level of

significance for the set degrees of freedom than the second hypothesis, H1, was accepted

to be true. The degrees of freedom for the linear correlation t-test was n-2. If the t*

values was found to be less than the to the null hypothesis was accepted and the H1

hypothesis was rejected.














CHAPTER 4
DISCUSSION: PILOT-SCALE BASIN

As stated previously, the pilot basin with the opaque cover that prevented solar

radiation exposure of the wastewater was termed the OPAQ basin. The basin with the

transparent cover that allows solar radiation (UV and global radiation) exposure of the

wastewater was termed the TRANS basin. For consistency, the comparisons between the

TRANS and OPAQ basin in all cases have the OPAQ basin effluent concentration

subtracted from the TRANS basin effluent concentration. The paired t-test statistical

analysis, along with the Pearson product momentum correlation coefficient, values used

in the following pilot-scale study discussion can be found in Appendix H.

Solar Radiation/Temperature

In this study, wastewater that had been treated by the KWRF through filtration was

put through one of two parallel pilot chlorine contact basins. The basins were identical

except that one pilot basin was covered with a plastic cover that allows UV and global

radiation to pass and come in contact with the wastewater (TRANS), while the second

basin was covered with a black plastic cover that was opaque to both the UV and global

radiation thus preventing the wastewater from becoming exposed to radiation (OPAQ).

The linear correlation between UV and global radiation is shown in Figure 4-1.

The Pearson product momentum correlation coefficient for this relationship was 0.996

and the resulting t-test showed a 99% confidence in a liner correlation between UV and

global radiation. Since, the radiation patterns match each other so well, only UV

radiation was used in the analysis of chlorine residual, DBP, and other parameter data.










120

100 -,



60 -
3 ~ 80 ------------- --



11X ~40

g 20


S 0.00 1.00 2.00 3.00 4.00 5.00
Average UV Radiation (mW/cm2)


Figure 4-1. Average global horizontal radiation versus the average UV radiation over the
HRT.

Solar radiation increases the temperature of exposed water. The TRANS basin had

a translucent cover allowing for the exposure to UV radiation during the chlorine

disinfection resulting in the increase in effluent temperature. As the average UV

radiation intensity increased during the day, the pilot basin effluent temperature also

increased. The effluent temperatures of both the pilot basins are plotted versus the

average UV radiation (Figure 4-2). An increase in solar radiation also results in an

increase in air temperature as well as the heating of the basins themselves. The

wastewater used in OPAQ basin was not exposed to solar radiation during the chlorine

disinfection process. However, before the pilot basins, the wastewater went through

previous KWRF treatment processes in which it was exposed to solar radiation. So it was

expected that the OPAQ basin effluent temperature would rise due to these conditions.










35.0
S33.0 *
31.0
S29.0 -
27.0 -
25.0 -
0.00 20.00 40.00 60.00 80.00 100.00 120.00

Average UV Radiation (mW/cm2)

TRANS (TEMP) OPAQ (TEMP)


Figure 4-2. The effluent temperature of the TRANS and OPAQ basins plotted versus the
average UV radiation exposure of the TRANS basin over the HRT.

To determine if the difference in UV radiation exposure of the basins caused the

effluent temperatures to differ, statistical paired t-tests were performed and the difference

in the effluent temperatures of the TRANS and OPAQ basins was plotted versus the

average UV radiation the wastewater was exposed to while in the pilot basin (Figure 4-3).

The results of the paired t-test showed a 99% confidence level that the basin effluent

temperatures were different. Therefore, the opaque cover of the OPAQ basin resulted in

a significantly lower effluent temperature. The Pearson product momentum correlation

coefficient for the relationship between the effluent temperature differences and the

average UV radiation exposure was 0.884 resulting in a 99% confidence in a linear

correlation. Thus, the higher effluent temperature of the TRANS basin over the OPAQ

basin can be attributed to an increase in the average solar radiation exposure while in the

basin. An increase in water temperature enhances the rate of reactions according to the

Arrhenius law. Therefore, the increase in water temperature results in an increase of

chlorine consumption in a variety of reactions and consequently results in lower chlorine









residual. Also, an increase in temperature will increase the formation of DBP, both

HAA(5) and TTHM, other variables being held constant.


4.0
0
3.0

I 2.0 *

S10

0.0
0.00 1.00 2.00 3.00 4.00 5.00

Average UV Radiation (mW/cm2)


Figure 4-3. Difference in effluent temperature of the basins (TRANS-OPAQ) plotted
versus the average UV radiation over the HRT.

Chlorine Residual

The chlorine residual was monitored during each experimental run of the pilot

basins; a constant chlorine dose was set for each pilot run. During the baseline runs the

HRT was 2.75 h and the chlorine dosing was kept between 7.5 and 8.0 mg/L Cl2, in

order to replicate full scale residual conditions, from between 4 pm the day prior to

sampling to 2 pm the day of the sampling. Because it was a pilot study, environmental

conditions like solar radiation and influent wastewater composition could not be

controlled. However, solar radiation, UV and global radiation, as well as pH,

temperature, dissolved oxygen, and conductivity were measured during the pilot studies

to determine the effect, if any, these factors have on chlorine residual and disinfection-

by-product (DBP) formation.

Because the pilot study used filtered wastewater from the KWRF the composition

of the wastewater was not controlled. Depending on the composition of the incoming









wastewater the chlorine demand and the DBP formation potential could change during

the course of the experimental run. The filtered wastewater was dosed with chlorine and

then split into the two parallel pilot basins. Though the influent wastewater could have

fluctuated in chlorine demand and DBP formation potential, each basin received the same

influent wastewater with the same pH and chlorine dose. Since it was a comparison

study of the two basin setups on the effect of solar radiation on chlorine residual,

disinfection effectiveness, and DBP formation, the fact that the influent wastewater

composition was not constant did not affect the outcome of the study. Accordingly,

statistical analyses were made with the paired t-test.32

Free Chlorine

As previously stated, KWRF uses Cl2 gas addition to disinfect the wastewater prior

to discharge, or reuse. The regulatory agencies, EPA and Florida DEP, require the

KWRF effluent to have a free chlorine residual of at least 1 mg/L Cl2. Other than the

chlorine demand of the wastewater, UV radiation also exerts some chlorine demand in

the wastewater, as shown earlier in Equation 1-1. Thus, enough chlorine must be

added to meet the chlorine demand of the wastewater, compensate for the UV radiation

exposure reduction, as well as maintain a sufficient effluent residual.

The effluent free chlorine residual data for the (TRANS-OPAQ) pilot basins was

partitioned into range increments for comparison (Figure 4-4). Most samples were in the

>2.0 mg/L Cl2 residual range increment for both the TRANS and OPAQ basins.

However, the OPAQ basin had a greater number of samples, 11, than the TRANS basin,

8, at the >2 mg/Cl2 residual increment. The higher chlorine residual ensures a greater

chemical disinfection potential.










12 -

10 -





: 4

2

0
<0.5 0.5-1.0 1.0-1.5 1.5-2.0 >2.0
Free Chlorine (mg/L C12)

TRANS Free C12 U OPAQ Free C12


Figure 4-4. Free chlorine residual sampling sets in particular residual ranges for the
TRANS and OPAQ basins.

The only difference between the two basins was the exposure to UV radiation, in

order to determine if this was the cause of the chlorine residual differences and to

ascertain if the differences between the two basins was statistically different, the

difference in the free chlorine residual of the (TRANS-OPAQ) basins for each

experimental run was plotted versus the average UV radiation the wastewater was

exposed to over the respective HRT (Figure 4-5). The majority of the points of the plot

were negative and were in the fourth quadrant, showing that the OPAQ basin effluent had

a higher chlorine residual than the TRANS basin in almost all of the sampling runs. Only

in three sampling times was the TRANS basin effluent free chlorine residual higher than

the OPAQ effluent. The largest free chlorine difference between the two basins was

-2.40 mg/L Cl2 (TRANS-OPAQ) at an average UV radiation exposure of 3.77 mW/cm2.

The average difference of free chlorine residual between the TRANS and OPAQ basins









for the 30 pilot study sampling sets was -0.44 mg/L Cl2. According to the paired t-test

analysis, there was 99% confidence that the free chlorine concentrations of the TRANS

and OPAQ basins were statistically different. The Pearson product momentum

correlation coefficient for the difference in effluent free chlorine residuals and the

average UV radiation was -0.405 signifying a 95% confidence that there was a negative

linear correlation. Thus, as the average UV radiation increased the difference in the

effluent free chlorine residuals of the basins increased.


1.50
1.00
0.50
1 0.00
" ,-0.50
u-1.00
|o o1.50
- 2.00
S-2.50
< -3.00


0.00 1.00 2.00 3.00 4.00 5.00
Average UV Radiation (mW/cm2)


Figure 4-5. Free chlorine residual difference of the TRANS and OPAQ basins
(TRANS-OPAQ) plotted versus average UV Radiation over the HRT of the
wastewater in the basin for all pilot studies.

A plot of only the baseline runs is shown in Figure 4-6. As in the plot of all

experimental runs, Figure 4-6 shows the OPAQ basin, the basin that was not exposed to

UV Radiation, had a greater free chlorine residual in all of the runs, except in one

sampling instance. According to the paired t-test method there was a 99% confidence

level that the TRANS and OPAQ basin effluent free chlorine residuals were different


4










during the baseline experiments. Using the paired t-test method the Pearson product

momentum correlation coefficient was -0.574 resulting in a 99% confidence that there

was a linear correlation between the difference in effluent free chlorine concentration and

UV radiation exposure of the wastewater for the baseline experiments.


1.50

CG 1.00
-e
S050

S0.00
o O
-0.50



1 .0
o s


* I I I I


-I.J J
0.00 1.00 2.00 3.00 4.00 5.00

Average UV Radiation (mW/cm2)



Figure 4-6. Free chlorine residual difference of the OPAQ and TRANS basins
(TRANS-OPAQ) plotted versus average UV radiation over the HRT of the
wastewater in the basin for baseline parameters.

Since UV radiation catalyzes the reduction of HOC1, it was to be expected that the

TRANS (UV and global radiation translucent plastic covered) basin would have a lower

effluent free chlorine residual than the OPAQ basin. The plots in Figures 4-5 and 4-6

support this expectation during the pilot study.

It is also commonly accepted, given that the chlorine dosing is constant, that as the

water or wastewater temperature increases, the amount of chlorine residual will decrease.

The difference in the free chlorine residual of the TRANS and OPAQ basins is shown

versus the difference in temperature between the basins (Figure 4-7). All except two









points were in the fourth quadrant, showing that TRANS had higher temperatures but

lower effluent free chlorine residuals than the OPAQ basin. Using the paired t-test

method the Pearson product momentum correlation coefficient was 0.334 resulting in a

95% confidence that there was a linear correlation between the difference in effluent free

chlorine concentration and the difference in temperature.


2.00


1.00

0 .00


I -1.00


-2.00


-3.00


**


0.0 1.0 2.0 3.0 4.0

ATemperature (C)


Figure 4-7. Free chlorine difference of the TRANS and OPAQ basins (TRANS-OPAQ)
plotted versus the difference in temperature for all of the pilot studies.

A plot of only the baseline runs is shown in Figure 4-8. As in the plot of all

experimental runs, the TRANS basin had higher effluent temperatures and lower effluent

free chlorine residual. The higher temperature causes a faster rate of chlorine reduction,

so the cause for greater chlorine loss in the TRANS basin was, in part, the result of this

phenomenon. According to the paired t-test the Pearson product momentum correlation

coefficient was 0.319 but did not result in a significant linear correlation between the









difference in effluent free chlorine concentration and the difference in temperature for the

baseline experiments.


1.50

1.00

o .oo
o 0.50

2 e0.00

2 -e -0.50
S-1.oo
S-1.00
-1.50


.1* I


0.00 1.00 2.00 3.00 4.00

A Temperature (C)


Figure 4-8. Free chlorine difference of the TRANS and OPAQ basins (TRANS-OPAQ)
plotted versus the difference in temperature for baseline parameters.

As expected, the TRANS, or UV and global radiation translucent plastic covered

basin had higher effluent temperatures than the OPAQ, or opaque covered, basin this

would contribute to the difference in chlorine residual. The one instance where the

TRANS basin free chlorine residual was higher than the OPAQ basin occurred on

7/14/2004 at 9 am. Prior to this time, during the HRTs for the samples taken at 9 am on

that day, a significant flow meter fluctuation was noticed and was adjusted for subsequent

sampling times on that day.

The pilot basin system was setup to simulate the hydraulic retention time (HRT),

flow pattern, and dimension ratios of the North and South chlorine contact basins that

were setup in series at the KWRF. However, the pilot system scale was much smaller

than that of the full-scale and thus the volume of water contained in the basins were less

than that of the full-scale. Thus, solar radiation had a greater effect on the pilot basin









temperature differences than the full-scale basin temperature differences. The average

temperature difference between the TRANS and OPAQ basins during the pilot study was

1.5 C while the average difference in temperature between the UNCOV and COV in the

full-scale sides was 0.3oC.

Total Chlorine

As stated previously, the total chlorine residual is a measure of the free and any

combined chlorine present. Since the KWRF uses biological processes, nitrification and

denitrification, to remove ammonia nitrogen present in the wastewater, it is unlikely that

chloramines would form. The KWRF operators add enough chlorine to pass the

breakpoint where free chlorine residual is formed. Thus, the difference in total and free

chlorine is what is termed "irreducible chlorine residual"1; though there are no inorganic

chloramines present, there is a difference in the total and free chlorine residuals. The

irreducible residual could be due, in part, to the presence of dichloramine and

trichloramine.

Since total chlorine residual consists mostly of free chlorine, the results and

relationships between the total chlorine residual and other parameters should be

comparable to those of the free chlorine residual. The environmental conditions that

result in a lowering of the free chlorine residual would also result in a decrease in the

total chlorine residual.

The effluent total chlorine residual data for the TRANS and OPAQ pilot basins was

partitioned into range increments for comparison (Figure 4-9). The most samples were in

the > 2.0 mg/L Cl2 residual range increment for both the TRANS and OPAQ basins.

However, the OPAQ basin had a greater number of samples, 22, than the TRANS basin,

15, at the >2 mg/Cl2 residual increment. As stated before, since the total chlorine residual









was composed mostly of free chlorine the results were similar to those shown for free

chlorine residual.


25



6 15 -

S 5 -----
0


0 -
<0.5 0.5-1.0 1.0-1.5 1.5-2.0 >2.0
Total Chlorine (mg/L C12)

TRANS Total C12 U OPAQ Total C12


Figure 4-9. Total chlorine residual sampling sets in particular residual ranges for the
TRANS and OPAQ basins.

The difference in the total chlorine residual of the (TRANS-OPAQ) basins is

shown versus the average UV radiation the wastewater was exposed to over the HRT

(Figure 4-10). The majority of the points were negative and were in the fourth quadrant,

showing that the OPAQ basin had higher effluent total chlorine residual than the TRANS

basin in nearly all of the sampling runs. Only in four sampling sets was the TRANS

basin effluent total chlorine residual higher than the OPAQ effluent. The largest total

chlorine difference between the two basins was -2.50 mg/L Cl2 (TRANS-OPAQ) at an

average UV Radiation exposure of 2.55 mW/cm2. The average difference of total

chlorine residual between the TRANS and OPAQ basins for the 30 pilot-scale sampling

sets was -0.50 mg/L Cl2 with a standard deviation of 0.67 mg/L Cl2. According to the

paired t-test method there was a 99% confidence level that the TRANS and OPAQ basin









effluent total chlorine residuals were different. Also, using the paired t-test method the

Pearson product momentum correlation coefficient was -0.281 and did not result in a

significant linear correlation between the difference in effluent total chlorine

concentration and UV radiation exposure of the wastewater. Thus, the total chlorine

difference was not significantly affected by the increases in the average UV radiation,

although the irradiated basin had significantly less total chlorine residual than the covered

basin.


1.00
0.50-

-0.50
S_ -1.00 *
F -1.50
H 5 -2.00
-2.50
-3.00
0.00 1.00 2.00 3.00 4.00 5.00
Avg UV Radiation (mW/cm2)


Figure 4-10. Total chlorine residual difference of the OPAQ and TRANS basins
(TRANS-OPAQ) plotted versus average UV Radiation over the HDT of
the wastewater in the basin for all pilot studies.

The difference in the total chlorine residual of the (TRANS-OPAQ) basins is

shown versus the difference in temperature between the basins (Figure 4-11). All except

two points were negative and were in the fourth quadrant, showing that TRANS had a

higher temperature but lower total chlorine residual than the OPAQ basin. Using the

paired t-test method the Pearson product momentum correlation coefficient was -0.227

and did not result in a significant linear correlation between the difference in effluent

total chlorine concentration and difference in temperature.









1.00

o 0.00

0 g-1.00

-H -2.00

-3.00


)


^ 2.0 3.0 4.0


ATemperature (C)


Figure 4-11. Total chlorine residual difference of the TRANS and OPAQ basins
(TRANS-OPAQ) plotted versus the difference in temperature between the
basins.

The basin with the higher effluent temperature also had significantly lower free and

total chlorine residual. Though, there was a 99% confidence level that the total chorine

residual was different between the two basins there was no significant correlation

between that difference and the exposure to UV radiation or difference in temperature.

Though it is important to note that solar radiation exposure of the wastewater does result

in an increase in water temperature, it is difficult to separate the effect of temperature

increase and UV radiation on the difference in chlorine residual in the TRANS and

OPAQ pilot basins.

Disinfection By-Products
The chlorination of KWRF wastewater ensures the safety of reuse water users and

prevents coliform and other bacterial contamination from entering the Floridan aquifer, a

drinking water source. Besides the consumption of chlorine through the disinfection

process, the reaction of chlorine with humic substances, extracellular algal products, and

other DBP precursors not only reduces the chlorine residual but also induces the


.~









formation of DBP. Because of the known carcinogenic health effects attributed to the

presence of DBP in drinking water, the EPA had placed an 80 [tg/L limit on TTHM

concentration and a 60 [tg/L limit on HAA(5) concentration. Although there are other

known disinfection by-products only trihalomethanes and haloacetic acids are regulated

by the EPA in the drinking water regulations and thus were the only DBP measured in

this study.

Several factors affect the extent of DBP formation, such as, chlorine dose,

temperature, pH, and contact time. It is commonly known that as the chlorine dosing is

increased during chlorination the amount of DBP that forms also increases.6 An increase

in temperature will also result in an increase in DBP formation.6

Trihalomethane

The TTHM concentration of effluent samples was analytically determined using

GC/MS instrumentation. The TTHM concentration in this study refers to a composite of

four molecules (chloroform, bromodichloromethane, dibromochloromethane, and

bromoform). In order to compare TTHM formation on a collective basis the mass

concentrations should be converted to a common unit and then summed. Molarity was

used as the common unit for this study as it is widely used. The THM speciation for each

of the sampling runs can be seen in Appendix E.

The TTHM effluent mass concentrations were separated into range increments and

plotted in a histogram (Figure 4-12). The concentrations are raw values in that they were

not normalized to pH, temperature, nor chlorine dose. The OPAQ basin had the same

number of samples, nine, in each range up to 150 tg/L and then only three samples in the

>200 gg/L range. Most of the effluent TTHM concentrations fell within the 50-100 gg/L







62


range for the TRANS basin, one sample in the 150-200 tg/L range, and three samples

>200 tg/L range. The TTHM effluent molar concentrations were separated into range

increments and plotted in a histogram (Figure 4-13). Most of the effluent TTHM

concentrations fell within the 0.5-1.0 tmole/L range for the TRANS basin and in the less

than 0.5 tmole/L for the OPAQ basin.


14
n 12
C 10 -

= 6
o 4
2
0
<50 50-100 100-150 150-200 >200

TTHM ([tg/L)

TRANS TTHM E OPAQ TTHM


Figure 4-12.






C.)



0
=ti


The TTHM effluent mass concentrations for the TRANS and OPAQ basins
are shown in range increments.


<0.5 0.5-1.0 1.0-1.5 1.5-2.0 >2.0
TTHM (pmoles/L)
TRANS TTHM U OPAQ TTHM

Figure 4-13. The TTHM effluent molar concentrations for the TRANS and OPAQ basins
are shown in range increments.









Previously, it was shown that the OPAQ basin, the basin with the cover that

prevented the wastewater from being exposed to UV radiation, had higher effluent free

chlorine residual than the TRANS basin for the majority of the pilot runs. Common

theory would then lead to the conclusion that the OPAQ basin, with a higher chlorine

residual, would result in a higher THM formation as well. The difference in the TRANS

and OPAQ TTHM mass and molar effluent concentrations for all of the pilot basin

experimental runs is shown as a histogram (Figures 4-14 and 4-15), respectively. The

differences in TTHM concentrations were the actual concentrations in the effluent

sample; the concentrations were not normalized for the differences in chlorine residual,

temperature or pH. There were 10 sampling sets of a total of 30 experimental sampling

sets where the OPAQ basin had a higher TTHM concentration than the TRANS basin.

Of the 10 sampling sets where the OPAQ basin had a higher TTHM effluent

concentration than the TRANS basin, 9 coincided with the OPAQ basin effluent having a

higher free chlorine residual that the TRANS basin. Also, of the sampling sets where the

OPAQ basin effluent had a higher TTHM concentration than the TRANS basin, 3 were

on the July 28, 2004 and 3 were on August 2, 2004. Both of those days were non-

baseline experimental pilot runs. On July 28th sodium hydroxide (NaOH) was added to

increase the influent pH to the basins. On August 2nd the flow rate was reduced from the

baseline flow rate of 28 GPH (HRT of 2 h and 45 min) to 20 GPH (HRT of 3 h and 50

min). In the rest of the 30 sampling sets the TRANS basin mass effluent concentration

was higher than that of the OPAQ basin. The average difference of effluent TTHM mass

concentration between the TRANS and OPAQ basins for the 30 pilot-scale sampling sets

was 6.9 [tg/L with a standard deviation of 29.1 [tg/L. The average difference of effluent






64


TTHM molar concentration between the TRANS and OPAQ basins for the 30 pilot-scale

sampling sets was 0.05 [tmole/L with a standard deviation of 0.22 [tmoles/L. According

to the paired t-test there was no significant difference between the TTHM effluent

concentration of the TRANS and OPAQ basins, mass or molar despite the typically

higher chlorine residual in the OPAQ basin.


12
10
8
6
O 4
S2
0
<=0 0-8 8-16 16-24 >24

ATTHM (jg/L)


Figure 4-14. Difference in TTHM concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into mass concentration ranges.




20

S15

S10o

a 5

0
<=0 0-0.25 0.25-0.50 0.50-0.75 >0.75

ATTHM ([tmoles/L)


Figure 4-15. Difference in TTHM concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into molar concentration ranges.









The difference in TTHM effluent concentration is plotted versus the difference in

free chlorine residual for mass and molar concentrations (Figures 4-16 and 4-17),

respectively. Using the paired t-test method, with the Pearson product momentum

correlation coefficient, neither the mass nor the molar TTHM concentration difference

correlates to a significant degree with the difference in free chlorine residual.


150
0100
50



-100

-3.00 -2.00 -1.00 0.00 1.00 2.00

AFree Chlorine (mg/L C12)


Figure 4-16. Difference in TTHM effluent mass concentration of the TRANS and OPAQ
basins (TRANS-OPAQ) plotted versus the difference in free chlorine
residual of the TRANS and OPAQ basins.


C)


1.00

0.50

0.00 -

-0.50

-1.00
-3.00 -2.00 -1.00 0.00 1.00 2.00

AFree Chlorine (mg/L)


Figure 4-17. Difference in TTHM effluent molar concentration of the TRANS and
OPAQ basins (TRANS-OPAQ) plotted versus the difference in free
chlorine residual of the TRANS and OPAQ basins.






66


The difference in the TRANS and OPAQ TTHM mass effluent concentrations for

baseline pilot basin experimental runs is plotted versus the difference in free chlorine

residual (Figure 4-18). In only one sample during the baseline runs was the OPAQ basin

TTHM effluent concentration higher than that of the TRANS basin. This one sample out

of nine sampling sets coincided with a higher free chlorine residual in the OPAQ basin

than the TRANS basin. Using the paired t-test the difference in TTHM effluent

concentration does not correlate to a significant degree with the difference in free

chlorine residual in the baseline experiments.


125

100
75
50



-25



-1.50 -1.00 -0.50 0.00 0.50 1.00 1.50
AFree Chlorine Residual (mg/LC12)


Figure 4-18. Difference in TTHM mass effluent concentration between the TRANS and
OPAQ basins (TRANS-OPAQ) plotted versus the difference in free
chlorine residual between the TRANS and OPAQ basins for baseline runs.

As stated previously, trihalomethane formation is affected by environmental

conditions, such as, temperature, pH, and free chlorine residual. The pH, temperature,

and free chlorine residual differences of the basins need to be addressed to allow an

accurate comparison of the trihalomethane formation in the two basins. In order to

compensate for the differences between these parameters in the basins' effluents the









TTHM concentrations were normalized. The manner in which the TTHM concentrations

were normalized is explained in the methods section. Each of the basin effluents,

TRANS and OPAQ, were sampled and trihalomethane concentrations were measured

during every sampling event and time.

The TTHM formation for all of the sampling runs for both the TRANS and OPAQ

basins was, for the most part, as chloroform. Chloroform made up at least 70%, by mass,

of the TTHM formed for both basins during each of the sampling runs of the chlorination

pilot study (Figure 4-19).




22%

4%

0%





Chloroform U Bromodichloromethane
E Dibromochloromethane E Bromoform


Figure 4-19. Speciation of the THM formation in the TRANS effluent on a mass basis
sampled at 9 am on August 23, 2004.

Because chloroform makes up 70% or higher, by mass, of the TTHM formed in the

pilot basins the THM model for chloroform formation was used in the normalization of

the OPAQ basin effluent TTHM concentration to that of the TRANS basin.

The average, minimum, and maximum values of the normalization factors used to

normalize the OPAQ effluent TTHM concentrations to the TRANS effluent TTHM

concentrations are shown in (Table 4-1). All TTHM normalized data can be found in









Appendix D. The average values of these normalization factors give an idea of how

much the difference in the parameter affects the TTHM concentration of the two basins.

The farther the normalization factor is from 1 the greater the parameter contributes to the

TTHM concentration difference between the basins. The free chlorine residual

normalization factor deviates the most from 1, with a value of 0.85, and thus is the

determining factor in the difference of the TTHM concentration between the two basins.

The chlorine residual having the greatest effect on the TTHM concentration difference of

the two basins is important in that in almost all of the cases the OPAQ basin had a higher

free chlorine residual effluent than the TRANS basin, however, the OPAQ basin in

almost all cases had a lower TTHM effluent concentration.

Table 4-1. Normalization factors used to normalize OPAQ TTHM effluent
concentrations to TRANS TTHM effluent concentrations.
Chlorine
pH Temperature residual
normalization normalization normalization
factor factor factor
OPAQ OPAQ OPAQ
Average 1.00 1.05 0.85
Maximum 1.06 1.13 1.44
Minimum 0.92 1.00 0.46

The TTHM mass concentration comparison was a good way to examine how the

two basin systems compare with EPA DBP drinking water standards. The effluent

normalized total trihalomethane (TTHM') mass and molar concentrations were separated

into range increments and plotted in a histogram (Figure 4-20 and 4-21), respectively.

The TRANS basin effluent TTHM' concentrations fell mostly in the 50-100 [tg/L range

while the OPAQ basin TTHM' effluent concentrations fell mostly in the less than 50

[tg/L range. Similarly, the TRANS basin TTHM' molar concentrations fell mostly in a

concentration range increment higher than the those of the OPAQ basin, 0.5-1.0 and <0.5






69


[tmole/L respectively. The results show the TRANS basin tending to produce effluent

TTHM' concentrations in a higher range than the OPAQ basin over several operating

conditions, described in Chapter 3 Materials and Methods.


<50 50-100 100-150 150-200 >200
TTHM' (pg/L)
U TRANS TTHM' U OPAQ TTHM'


Figure 4-20. Normalized TTHM effluent mass concentrations for the TRANS and
OPAQ basins are shown in range increments.


<0.5 0.5-1.0 1.0-1.5 1.5-2.0
TTHM' (Gmoles/L)
U TRANS TTHM' U OPAQ TTHM'


>2.0


Figure 4-21. Normalized TTHM effluent molar concentrations for the TRANS and
OPAQ basins are shown in range increments.


'I 'I I









The difference in the normalized TTHM concentration (ATTHM') was separated

into mass concentration ranges (Figure 4-22). In only seven sampling sets was the

OPAQ basin TTHM' concentration higher than the TRANS basin effluent concentration.

Most sampling sets of the TTHM mass concentration difference were in the >24 [tg/L

range, with 10 sampling sets. There were then five sampling sets where the difference

between the TRANS and OPAQ basin were in the 0 to 8 [tg/L and five sampling sets in

the 8 to 16 [tg/L ranges. Using the paired t-test method there was a 99% confidence level

that there was a difference between the TRANS basin TTHM' concentration and the

OPAQ basin TTHM' concentration.


10

8

6

4

2

0
<0 0-8 8-16 16-24 >24
ATTHM' ([g/L)


Figure 4-22. Difference in TTHM' concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into mass concentration ranges.

The difference in the normalized TTHM concentration was separated into molar

concentration ranges (Figure 4-23). Again, the histogram shows that in only seven

sampling sets did the OPAQ basin have a higher TTHM concentration than the TRANS

basin. Most sampling sets of the TTHM molar concentration difference were in the 0 to






71


0.25 [tmoles/L range. There were then two sampling sets where the difference between

the TRANS and OPAQ basin were in the 0.25 to 0.50 [tmoles/L and two sampling sets in

the 0.50 to 0.75 [tmoles/L ranges. Using the paired t-test method there was a 99%

confidence level that there was a difference between the TRANS basin TTHM'

concentration and the OPAQ basin TTHM' concentration. Thus, the TRANS basin

TTHM' concentrations were significantly higher than the OPAQ basin TTHM'

concentrations.


20
18
16
S14
= 12
10 -
S8
6 s


-
4
2
0


<0 0-0.25 0.25-0.50 0.50-0.75 >0.75
ATTHM' (tmoles/L)


Figure 4-23. Difference in TTHM' concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into molar concentration ranges.

The difference in the normalized TTHM mass concentrations were plotted versus

the average UV radiation exposure of the TRANS basin over the HRT (Figure 4-24).

The majority of the points, all but 7, were in the first quadrant meaning that the OPAQ

basin had a lower normalized TTHM effluent concentration than the TRANS basin in

almost all of the sampling periods. The average difference of the normalized effluent

TTHM concentration between the TRANS and OPAQ basins for the 30 pilot-scale









sampling sets was 17.1 [tg/L with a standard deviation of 31.6 [tg/L. Using the paired t-

test the normalized difference in TTHM effluent concentration does not correlate to a

significant degree with the average UV radiation exposure.


140.0
120.0 A
100.0
80.0 -
o 60.0
40.0 A
S20.0 -
2 0.0- L-A A -- AA A A
H 0.0 4- -A K ,
< -20.0 -
-40.0
-60.0 A
-80.0
0.00 1.00 2.00 3.00 4.00 5.00
Average UV Radiation (mW/cm2)


Figure 4-24. Difference in normalized TTHM mass concentration of the TRANS and the
OPAQ basins (TRANS-OPAQ) plotted versus the average UV radiation.
exposure over the HRT.

The difference in the normalized TTHM molar concentrations was plotted versus

the average UV radiation the TRANS basin was exposed to over the HRT (Figure 4-25).

The majority of the points, all but 7, were in the first quadrant meaning that the OPAQ

basin had a lower TTHM effluent concentration than the TRANS basin in almost all of

the sampling periods. The average difference of the normalized effluent TTHM molar

concentration between the TRANS and OPAQ basins for the 30 pilot-scale sampling sets

was 0.13 [tmoles/L with a standard deviation of 0.24 [tmoles/L. Using the paired t-test

the normalized difference in TTHM effluent concentration does not correlate to a

significant degree with the average UV radiation exposure.










1.00
0.80
0.60
0.40
0.20
0.00
-0.20
-0.40
-0.60


1 .


0.00 1.00 2.00 3.00 4.00 5.00
Average UV Radiation (mW/cm2)


Figure 4-25. Difference in normalized TTHM molar concentration of the TRANS and
the OPAQ basins (TRANS-OPAQ) plotted versus the average UV radiation
exposure over the HRT.

The fact that in all but seven sampling sets the OPAQ basin had a lower TTHM

concentration than the TRANS basins was contrary to the common theory that a higher

residual will result in a higher TTHM concentration. The TTHM and chlorine data

analysis suggest that the chlorine disinfection process tends to produce less TTHMs if

UV radiation and solar radiation exposure of the wastewater was prevented. The data

also validate the common concept that UV radiation catalyzes the reduction of free

chlorine (HOC1).

The data analyses suggest that the OPAQ basin, with the opaque cover that

prevents wastewater exposure to UV radiation during the chlorination disinfection

process, for the majority of sampling sets, had a lower formation of THM than the

TRANS basin. This phenomenon contrasts with the more common theory that a higher

chlorine residual will result in a greater formation of THM. The difference between the

basins was the exposure of the wastewater to UV radiation during the chlorination

disinfection process. The data and statistical analysis suggest that preventing UV









radiation and solar radiation exposure of wastewater during the chlorine disinfection

stage at the KWRF had two benefits:

1. The prevention of chlorine loss to the free chlorine reduction reaction by removing
the UV radiation as the catalyst

2. A lower THM concentration than with the conventional method of allowing UV
radiation to come in contact with wastewater during the chlorine disinfection stage
in the KWRF treatment process.

Haloacetic Acid

The HAA(5) concentration of an effluent sample is the summed values of the

monochloroacetic acid (MCAA), monobromoacetic acid (MBAA), dichloroacetic acid

(DCAA), dibromoacetic acid (DBAA), and trichloroacetic acid (TCAA) concentrations

calculated for the said sample using the GC/ECD. The HAA(5) speciation for each of the

sampling runs can be seen in Appendix E. In order to compare HAA(5) formation on a

collective basis the mass concentrations should be converted to a common unit and then

summed. The HAA(5) wastewater effluent samples taken from the OPAQ basin on June

23, at 9am, and the TRANS basin on July 14, at 2 pm, and July 26, at 9 am, were

damaged prior to analysis and were not used in the pilot-study discussion.

The HAA(5) effluent mass concentrations were separated into range increments

and plotted in a histogram (Figure 4-26). The concentrations are raw values in that they

were not normalized to temperature or chlorine residual. Most of the effluent HAA(5)

concentrations fell within the less than 50 [tg/L range for the TRANS basin and the

OPAQ basin, with 11 and 17 samples respectively. The HAA(5) effluent molar

concentrations were separated into range increments and plotted in a histogram

(Figure 4-27). Most of the effluent HAA(5) concentrations fell within the less than

0.5 [tmole/L range for the TRANS basin and the OPAQ basin, with 24 and 25 samples,









respectively. It is good to note that the majority of the TRANS and OPAQ basin HAA(5)

effluent concentrations fall in the range that is below the proposed EPA standard.


18
16
6 14
= 12
10
8
o 6
4


2
1-


<50 50-100 100-150 150-200 >200
HAA (kgL)
TRANS HAA E OPAQ HAA


Figure 4-26. The HAA(5) effluent mass concentrations for the TRANS and OPAQ
basins are shown in range increments.

28
n 24 -
o 20
16
S12 -
o 8
4
0
<0.5 0.5-1.0 1.0-1.5 1.5-2.0 >2.0
HAA ([tmoles/L)
TRANS HAA U OPAQ HAA


Figure 4-27. The HAA(5) effluent molar concentrations for the TRANS and OPAQ
basins are shown in range increments.

The difference in the HAA(5) concentrations (AHAA(5)) were separated into mass

and molar concentration ranges in (Figure 4-28 and 4-29), respectively. In eighteen of

the twenty-seven sampling sets the TRANS basin HAA(5) mass concentration was higher

than the OPAQ basin effluent concentration and in sixteen of the twenty-seven sampling

sets the TRANS basin molar concentration was greater than the OPAQ basin








concentration. In the HAA(5) mass concentration difference histogram the most

sampling sets were in the <=0 tg/L range due to the concentrations being distributed

amongst the higher ranges. The average difference in HAA(5) effluent mass

concentration was 7.22 [tg/L with a standard deviation of 32 [tg/L. Most sampling sets in

the HAA(5) molar concentration difference histogram were in the 0-0.25 [tmole/L range,

with thirteen sampling sets. The average difference in HAA(5) effluent molar

concentration was 0.02 [tmole/L with a standard deviation of 0.26 [tmoles/L. Using the

paired t-test method it was determined that there was no significant difference between

the TRANS and OPAQ effluent HAA(5) concentrations.


8-16
AHAA ([tg/L)


16-24 >24


Figure 4-28.


Difference in HAA(5) concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into mass concentration ranges.


<=0 0-0.25 0.25-0.50 0.50-0.75 >0.75
AHAA (omoles/L)
Figure 4-29. Difference in HAA(5) concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into molar concentration ranges.


<=0


I I









The difference in HAA(5) effluent mass concentrations of the TRANS and OPAQ

basins was plotted versus the difference in free chlorine residual of the TRANS and

OPAQ basins (Figure 4-30). As stated previously, in eighteen of the twenty-seven

sampling sets the TRANS basin HAA(5) effluent mass concentrations were higher than

those of the OPAQ basin. Using the paired t-test method, with the Pearson product

momentum correlation coefficient, it was determined that there was no significant

correlation between the difference in HAA(5) mass concentration and the difference in

free chlorine residual.


100

75

50

25

0

-25

-50

-75

-100


I.


-3.00 -2.00 -1.00 0.00 1.00 2.00
AFree Chlorine Residual (mg/L C12)


Figure 4-30. Difference in HAA(5) mass concentration of the TRANS and the OPAQ
basins (TRANS-OPAQ) plotted versus the difference in free chlorine
residual of the TRANS and OPAQ basins (TRANS-OPAQ).

The difference in HAA(5) effluent molar concentrations of the TRANS and

OPAQ basins was plotted versus the difference in free chlorine residual of the TRANS

and OPAQ basins in (Figure 4-31). In sixteen of the twenty-seven sampling sets the

TRANS basin HAA(5) effluent concentrations were higher than those of the OPAQ









basin. Using the paired t-test method, with the Pearson product momentum correlation

coefficient, it was determined that there was no significant correlation between the

difference in HAA(5) molar concentration and the difference in free chlorine residual.


0.80
0.60
0.40
0.20
0.00
-0.20
-0.40
-0.60
-0.80


S*




.

4 *^


-3.00 -2.00 -1.00 0.00 1.00 2.00
AFree Chlorine Resdual (mg/L C12)


Figure 4-31. Difference in HAA(5) molar concentration of the TRANS and the OPAQ
basins (TRANS-OPAQ) plotted versus the difference in free chlorine
residual of the TRANS and OPAQ basins (TRANS-OPAQ).

Neither the HAA(5) concentration or the TTHM concentration effluent differences

correlate with the difference in effluent free chlorine residual.

In the HAA(5) analysis in all but three of the thirty sampling sets the DCAA made

up the highest percentage of the HAA(5)s. Thus, the HAA(5) OPAQ basin effluent

HAA(5) concentrations were normalized to the HAA(5) TRANS basin effluent using the

temperature and free chlorine concentration DCAA normalization factors. The speciation

of HAA(5) in the OPAQ basin effluent during a baseline run on August 30, 2004 taken at

12 pm is shown with species percentage (Figure 4-32). In this case, DCAA made up 58%

of the HAA(5) mass concentration.














42%
0%




S58%

0%



SMCAA MBAA DCAA DBAA TCAA


Figure 4-32. Speciation of the HAA(5) formation in the OPAQ effluent on a mass basis
sampled at 12 pm on August 30, 2004.

Like THM formation, HAA(5) formation is affected by environmental conditions,

such as, temperature and free chlorine residual. In order to compensate for the

differences between these parameters in the basins' effluents the HAA(5) concentrations

were normalized. All HAA(5) normalized data can be found in Appendix D.

Normalized HAA(5) concentrations, mass and molar, are denoted as HAA(5)'. Though

DCAA did not make up the highest percentage in all sampling sets it did make up the

highest percentage of the HAA(5) concentrations in the most numerous sampling sets.

The average, minimum, and maximum values of the normalization factors used to

normalize the OPAQ effluent HAA(5) concentrations to the TRANS effluent HAA(5)

concentrations is shown (Table 4-2). The average values give an idea of how much the

difference in the parameter affects the HAA(5) concentration of the two basins. The

farther the normalization factor is from 1 the greater the parameter contributes to the

HAA(5) concentration difference between the basins. The free chlorine residual

normalization factor deviates the most from 1, with an average value of 0.86, and thus is









the determining factor in the difference of the HAA(5) concentration between the two

basins according to the model. The chlorine residual having the greatest effect on the

HAA(5) concentration difference of the two basins is important in that in almost all of the

cases the OPAQ basin had a higher free chlorine residual effluent than the TRANS basin,

however, the OPAQ basin in eighteen of the twenty-seven sampling sets had a lower

normalized HAA(5) mass effluent concentration.

Table 4-2. Normalization factors used to normalize OPAQ HAA(5) effluent
concentrations to TRANS HAA(5) effluent concentrations.

Chlorine
Temp (C) Residual
Normalization Normalization
Factor Factor
OPAQ OPAQ
Average 1.03 0.86
Maximum 1.08 1.36
Minimum 1.00 0.51

The HAA(5)' effluent mass concentrations were separated into range increments

and plotted in a histogram (Figure 4-33). Similar to the raw HAA(5) histogram, most of

the effluent HAA(5)' concentrations fell within the less than 50 [g/L range for the

TRANS basin and the OPAQ basin, with eleven and sixteen samples respectively. The

HAA(5)' effluent molar concentrations were separated into range increments and plotted

in a histogram (Figure 4-34). Similar to the raw HAA(5) histogram, most of the effluent

HAA(5)' molar concentrations fell within the less than 0.5 kmole/L range for the TRANS

basin and the OPAQ basin, with twenty-five and twenty-six samples, respectively.

Similar to the raw HAA(5) concentrations, the majority of the TRANS and OPAQ basin

HAA(5)' effluent concentrations fall in the range that is below the proposed EPA

standard.









20

16

12

8-


<50 50-100 100-150 150-200
HAA' (tg/L)

m TRANS HAA' N OPAQ HAA'


>200


Figure 4-33. The HAA(5)' effluent mass concentrations for the TRANS and OPAQ
basins are shown in range increments.


30
25
20
15
10
5
0


<0.5 0.5-1.0 1.0-1.5 1.5-2.0
HAA' (tmoles/L)
TRANS HAA' OPAQ HAA'


>2.0


Figure 4-34. The HAA(5)' effluent molar concentrations for the TRANS and OPAQ
basins are shown in range increments.

The difference in the HAA(5)' concentrations (AHAA(5)') were separated into

mass and molar concentration ranges in (Figure 4-35 and 4-36), respectively. In eighteen


-L L-.






82


of the twenty-seven sampling sets the TRANS basin HAA(5)' mass concentration was

higher than the OPAQ basin effluent concentration and in nineteen of the thirty sampling

sets the TRANS basin molar concentration was greater than the OPAQ basin

concentration. In the HAA(5)' mass concentration difference histogram the same number

of sampling sets were in the <=0 [g/L range. The average difference in HAA(5)' effluent

mass concentration was 9.05 [tg/L with a standard deviation of 31.9 |tg/L. Most

sampling sets in HAA(5)' molar concentration difference histogram were in the 0-0.25

jtmole/L range, with fourteen sampling sets. The average difference in HAA(5)' effluent

molar concentration was 0.04 [tmole/L with a standard deviation of 0.25 [tmoles/L.

Using the paired t-test method it was determined that there was no significant difference

between the TRANS and OPAQ effluent HAA(5) concentrations.


10
9
8
CA 7
6
5
S4
3
2
1
0
<=0 0-8 8-16 16-24 >24

AHAA' (g/L)

Figure 4-35. Difference in HAA(5)' concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into mass concentration ranges.










14
12
10


6
4
2


<=0 0-0.25 0.25-0.50 0.50-0.75 >0.75
AHAA' (tmoles/L)


Figure 4-36. Difference in HAA(5)' concentration between the TRANS and OPAQ sides
(TRANS-OPAQ) separated into molar concentration ranges.

The HAA(5)' concentration differences histograms are visually similar to those of

for the HAA(5) concentration differences histograms but are slightly shifted in favor of a

greater difference in the OPAQ and TRANS basin effluent concentrations. This results

from the normalization process, for every sampling set where the OPAQ basin effluent

free chlorine residual was higher that that of the TRANS basin the HAA(5), DCAA,

formation equation favored a higher OPAQ effluent HAA(5) concentration over the

TRANS basin effluent. However, since the opposite was the case, the OPAQ basin had

in all but the three sampling sets a higher free chlorine effluent residual than the TRANS

basin, the normalization factor for free chlorine residual was, in all but those three

sampling sets, less than one. In the twenty-seven sampling sets where the OPAQ basin

effluent free chlorine residual was greater than that of the TRANS basin, the OPAQ basin

effluent HAA(5)' concentrations were greater than the raw, non-normalized, effluent

HAA(5) concentrations which in turn increased the difference in the TRANS and OPAQ

basin effluent concentrations for those sampling sets.