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Characterization of Natural Organic Matter (NOM) and Tracking the Changes in its Composition while Removing Phosphorus f...

Permanent Link: http://ufdc.ufl.edu/UFE0041791/00001

Material Information

Title: Characterization of Natural Organic Matter (NOM) and Tracking the Changes in its Composition while Removing Phosphorus from Surface Water
Physical Description: 1 online resource (63 p.)
Language: english
Creator: Banerjee, Poulomi
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2010

Subjects

Subjects / Keywords: Environmental Engineering Sciences -- Dissertations, Academic -- UF
Genre: Environmental Engineering Sciences thesis, M.E.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: A substantial amount of work has been focused on the existing conditions of natural organic matter (NOM) in surface waters, and various treatment methods for control of eutrophication in surface waters. A lack of research on the changes in NOM while removing phosphorus, especially at the pilot- or field-scale, was the motivation for this work. The overall goal of this work was to characterize NOM and track the changes in its concentration and composition while removing phosphorus from surface water. Various low cost materials (LCMs)like waste by products (i.e. clarifier sludge) from water treatment plants and industries (e.g. Tampa Bay Surface water treatment plant, Cape Canaveral Iron industry) were utilized along with ion exchange resins, engineered resins from industry to analyze their effects on NOM while removing phosphorus from surface water in jar test experiments. It was found that some LCMs threatened the water quality index of the water, by increasing the total organic content (TOC) in water. Although LCMs like alum sludge (AS) was predicted to uptake larger NOM molecules since it is assumed to have greater adsorption sites, it performed otherwise. It may be concluded that continuous flow of water in laboratory column test experiments led to a decrease in its NOM removal capacity and hence could be better utilized in further phosphorus removal studies. The phosphorus removal methods carried out in a floating island treatment system (FITS) study maintained the NOM levels close to the initial levels. Thus, we may assume that these phosphorus removal methods do not tend to change the NOM balance of surface water. The findings in this study show that although NOM is removed by the phosphorus removal methods, specific ultraviolet (UV) absorbance (SUVA or SUVA254) defined as the ratio of water sample's UV absorbance at 254nm by the dissolved organic carbon (DOC) concentration of the water was not affected. The possibility of PhosX resin and alum sludge removing equal amounts of UV- and non-UV-absorbing NOM fractions from the water is discussed. Moreover, it was established that the intermittent runs in the FITS successfully conserved NOM levels closer to initial levels as compared to the continuous runs. NOM-sustainability paves the way for continued application and further research of FITS with respect to Alum sludge and PhosX resin for phosphorus removal method.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Poulomi Banerjee.
Thesis: Thesis (M.E.)--University of Florida, 2010.
Local: Adviser: Boyer, Treavor H.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2012-04-30

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2010
System ID: UFE0041791:00001

Permanent Link: http://ufdc.ufl.edu/UFE0041791/00001

Material Information

Title: Characterization of Natural Organic Matter (NOM) and Tracking the Changes in its Composition while Removing Phosphorus from Surface Water
Physical Description: 1 online resource (63 p.)
Language: english
Creator: Banerjee, Poulomi
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2010

Subjects

Subjects / Keywords: Environmental Engineering Sciences -- Dissertations, Academic -- UF
Genre: Environmental Engineering Sciences thesis, M.E.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: A substantial amount of work has been focused on the existing conditions of natural organic matter (NOM) in surface waters, and various treatment methods for control of eutrophication in surface waters. A lack of research on the changes in NOM while removing phosphorus, especially at the pilot- or field-scale, was the motivation for this work. The overall goal of this work was to characterize NOM and track the changes in its concentration and composition while removing phosphorus from surface water. Various low cost materials (LCMs)like waste by products (i.e. clarifier sludge) from water treatment plants and industries (e.g. Tampa Bay Surface water treatment plant, Cape Canaveral Iron industry) were utilized along with ion exchange resins, engineered resins from industry to analyze their effects on NOM while removing phosphorus from surface water in jar test experiments. It was found that some LCMs threatened the water quality index of the water, by increasing the total organic content (TOC) in water. Although LCMs like alum sludge (AS) was predicted to uptake larger NOM molecules since it is assumed to have greater adsorption sites, it performed otherwise. It may be concluded that continuous flow of water in laboratory column test experiments led to a decrease in its NOM removal capacity and hence could be better utilized in further phosphorus removal studies. The phosphorus removal methods carried out in a floating island treatment system (FITS) study maintained the NOM levels close to the initial levels. Thus, we may assume that these phosphorus removal methods do not tend to change the NOM balance of surface water. The findings in this study show that although NOM is removed by the phosphorus removal methods, specific ultraviolet (UV) absorbance (SUVA or SUVA254) defined as the ratio of water sample's UV absorbance at 254nm by the dissolved organic carbon (DOC) concentration of the water was not affected. The possibility of PhosX resin and alum sludge removing equal amounts of UV- and non-UV-absorbing NOM fractions from the water is discussed. Moreover, it was established that the intermittent runs in the FITS successfully conserved NOM levels closer to initial levels as compared to the continuous runs. NOM-sustainability paves the way for continued application and further research of FITS with respect to Alum sludge and PhosX resin for phosphorus removal method.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Poulomi Banerjee.
Thesis: Thesis (M.E.)--University of Florida, 2010.
Local: Adviser: Boyer, Treavor H.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2012-04-30

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2010
System ID: UFE0041791:00001


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1 CHARACTERIZATION OF NATURAL ORGANIC MATTER (NOM) AND TRACKING THE CHANGES IN ITS COMPOSITION WHILE REMOVING PHOSPHORUS FROM SURFACE WATER By POULOMI BANERJEE 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 2010

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2 2010 Poulomi Banerjee

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3 To my husband, Saurav; my mom, Ma; my dad, Bapi ; and my baby sister, Mohor

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4 ACKNOWLEDGMENTS I would like to express my gratitude for Dr. Treavor Boyer for guiding me through my graduate research. I would like to thank Dr. David Mazyck and Dr. Joseph Delfino for their support and suggestions during my research. I would like to acknowledge Dr. Mark Brown and his lab members for their cooperation on this project. I also thank the St. Johns River Water Management District and project manager Dr. Sherry Brandt Treatment Technol Lastly, I would like to thank Amar Persaud for providing the samples and helping with the experiments for my study. I would also like to thank all my family and friends without whose support this would not have been po ssible.

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5 TABLE OF CONTENTS Page ACKNOWLEDGMENTS ................................ ................................ ................................ .. 4 LIST OF TABLES ................................ ................................ ................................ ............ 7 LIST OF FIGURES ................................ ................................ ................................ .......... 8 LIST OF ABBREVIATI ONS ................................ ................................ ........................... 10 ABSTRACT ................................ ................................ ................................ ................... 12 CHAPTER 1 OVERVIEW ................................ ................................ ................................ ............ 14 Introduction ................................ ................................ ................................ ............. 14 Background and Significance ................................ ................................ ................. 15 2 MATERIALS AND METHODS ................................ ................................ ................ 20 Surface Waters ................................ ................................ ................................ ....... 20 Materials ................................ ................................ ................................ ................. 21 Jar Test Procedure ................................ ................................ ................................ 21 Column Test Procedure ................................ ................................ .......................... 22 Floating Island Treatment System ................................ ................................ .......... 23 Analytical Methods ................................ ................................ ................................ .. 24 3 RESULTS AND DISCUSSION ................................ ................................ ............... 26 Jar T ests ................................ ................................ ................................ ................. 28 Laboratory Column Tests ................................ ................................ ........................ 33 Continuo us F low T reatment ................................ ................................ ............. 33 Intermittent F low T reatment ................................ ................................ .............. 36 Comparison of C ontinuous and I ntermittent F low ................................ ............. 37 Floating Island Treatment System ................................ ................................ .......... 37 4 SU MMARY AND CONCLUSIONS ................................ ................................ .......... 40 APPENDIX A CHARACTERIZATION OF NOM ................................ ................................ ........... 42 B JAR TESTING FIGURES ................................ ................................ ........................ 44 C COLUMN T ESTING FIGURES ................................ ................................ ............... 50

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6 D PILOT TESTING FIGURES ................................ ................................ .................... 56 LIST OF REFERENCES ................................ ................................ ............................... 59 BIOGRAPHICAL S KETCH ................................ ................................ ............................ 63

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7 LIST OF TABLES Table page A 1 Water quality characteristics for Lake Jesup and Sanford Avenue Canal .......... 42 A 2 Water quality characteristics for Sanford Avenue Canal and Lake Alice ............ 42 A 3 Quantification of EEMs fluorescence ................................ ................................ .. 43 A 4 Major fluorescent components in EEM ................................ ............................... 43

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8 LIST OF FIGURES Figure page B 1 Fluorescence EEMs for (A) Lake Jesup and (B) Sanford Avenue Canal water samples from March 2009. ................................ ................................ ................. 44 B 2 Change in pH following 60 min of treatment of Canal water by (A) ion exchange resins and (B) low cost materials. ................................ ...................... 45 B 3 Rate of removal of UV 254 absorbing substances by (A) ion exchange resins dosed at 1 and 4 mL/L and (B) low cost materials dosed at 4 g/L in Sanford Avenue Canal water. Initial UV 254 = 0.81 1.04 cm 1 ................................ .......... 45 B 4 Change in TOC and SUVA following 60 min of treatment by (A) ion exchange resins and (B) low cost materials. TOC FS = 34.6 mg/L. ................................ .... 46 B 5 Fluorescence EEMs for Sanford Avenue Canal water treated with (A) AS dosed at 4mg/L, (B) PX dosed at 2mL/L. ................................ ............................ 47 B 6 Change in chloride and sulfate following 60 min of treatment of Sanford Avenue Canal water by (A) io n exchange resins and (B) low cost materials ion exchange resins. Initial chloride = 112 191 mg/L; initial sulfate = 22.5 40.6 mg/L. ................................ ................................ ................................ .......... 48 B 7 Total Nitrogen remaining after 60 min of treatment of Sanford Avenue Canal water by (A) ion exchange resins and (B) low cost materials ion exchange resins. Initial TN = 0.81 1.43 mg N/L. ................................ ................................ 49 C 1 Change in pH following column test of Sanford Avenue Canal April water by AS and PX. ................................ ................................ ................................ ......... 50 C 2 Change in TOC following column test of Sanford Avenue Canal April water for AS and PX. ................................ ................................ ................................ .... 50 C 3 Rate of removal of UV 254 absorbing substances following column test of Sanford Avenue Canal April water for AS and PX. Initial UV 254 = 0.576 0.612 cm 1 ................................ ................................ ................................ .................... 51 C 4 Change in chloride following column test of Sanford Avenue Canal April water for AS and PX. Initial chloride = 169 198 mg/L. ................................ ....... 51 C 5 Change in sulfate following column test of Sanford Avenue Canal April water for AS and PX. Initial sulfate = 30 34.4 mg/L. ................................ .................... 52 C 6 Change in TOC following 12 hr On 12 hr Off (12/12) column tests by PX and AS on Lake Alice August. Initial TOC = 8.1 mg/L as C. ............................... 52

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9 C 7 Change in SUVA following 12 hr On 12 hr Off (12/12) column tests by PX and AS on Lake Alice August. ................................ ................................ ............ 53 C 8 Comparison in change in TOC following Continous, 12/12 column tests for PX. Initial TOC (Continuous) = 7.1 mg/L as C; Initial TOC (12/12) = 8.1 mg/L as C. ................................ ................................ ................................ ................... 53 C 9 Comparison in change in SUVA following Continous, 12/12 column tests for PX. ................................ ................................ ................................ ...................... 54 C 10 Comparison in change in TOC following Continous, 12/12 column tests for AS. Initial TOC (Continuous) = 7.1 mg/L as C; Initial TOC (12/12) = 8.1 mg/L as C. ................................ ................................ ................................ ................... 54 C 11 Comparison in change in SUVA following Continous, 12/12 column tests for AS. ................................ ................................ ................................ ...................... 55 D 1 Change in pH following FITS with LA water. Date from 10/10 to 10/19/2009. .... 56 D 2 Comparison of change in absolute values of TOC following FITS procedure for PX,and AS. Date from 10/10 to 10/19/2009. ................................ ................. 56 D 3 Comparison of change in SUVA following FITS procedure for PX and AS. Date from 10/10 to 10/10/2009. ................................ ................................ .......... 57 D 4 Comparison of change in TOC following FITS procedure for PX during entire study. ................................ ................................ ................................ .................. 57 D 5 Comparison of change in SUVA following FITS procedure for PX during entire study. ................................ ................................ ................................ ........ 58

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10 LIST OF ABBREVIATION S 12/12 12 hours on then twelve hours off AS Alum S ludge Bio water Biologically treated water BV Bed Volume Cm Centimeter DI Deionized DOC Dissolved organic carbon; experimentally defined as the carbon DOM Dissolved organic matter DX Dowex22 DX (1) Dowex22 dosed at 1mL/L DX (4) Dowex22 dosed at 4 mL/L FA Fly Ash FITS Floating Island Treatment System FS Ferric Sludge Gpm Gallon per minute IEX ion exchange IS Granulated Blast Furnace Iron Slag L Liter LA Lake Alice LCMs Low Cost Materials LJ Lake Jesup LS Limestone min Minute mL Milliliter

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11 MX MIEX resin MX (1) MIEX Dos ed at 1mL/L MX (4) MIEX dosed at 4mL/L NOM Natural organic matter N Nitrogen P Phosphorus PAC Powder Activated Carbon PX PhosX resin PX (1) PhosX dosed at 1 mL/L PX (4) PhosX dosed at 4 mL/L RC Re cycled Concrete SUVA / SUVA 254 Specific ultraviolet absorbance at 254 nm; defined as UV 254 divided by the dissolved organic carbon SJRWMD St. Johns River Water Management District SS Basic Oxygen Furnace Steel Slag TN Total Nitrogen TP Total Phosphorus UV 254 Ultraviolet absorbance at 254 nm

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12 Abstract of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Engineering CHARACTERIZATION OF NATURAL ORGANIC MATTER (NOM) AND TRACKING THE CHANGES IN ITS QUANTITY AND COMPOSITION WHILE REMOVING PHOSPHORUS FROM SURFACE WATER By Poulomi Banerjee May 2010 Chair: Treavor H. Boyer Major: Environmental En gineering Sciences A substantial amount of work has been focused on the existing conditions of natural organic matter (NOM) in surface waters, and various treatment methods for control of eutrophication in surface waters. A lack of research on the changes in NOM while removi ng phosphorus, especially at the pilot or field scale, was the motivation for this work. The overall goal of this work was to characterize NOM and track the changes in its concentration and composition while removing phosphorus from surface water. Various low cost materials (LCMs) like waste byproducts (i.e., clarifier sludge) from water treatment plants and industries (e.g., i ron industry ) were utilized along with ion exchange resins, engineered resins from industry to analyze their effects on NOM while r emoving phosphorus from surface water in jar test experiments. It was found that some LCMs threatened the water quality index of the water, by increasing the total organic content in water. Although LCMs like alum sludge was predicted to uptake larger NOM molecules since it is assumed to have greater adsorption sites, it performed otherwise. It may be concluded that continuous flow of water in laboratory column test experiments

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13 led to a decrease in its NOM removal capacity and hence could be better utilized in further phosphorus removal studies. The phosphorus removal methods carried out in a floating island treatment system (FITS) study maintained the NOM levels close to the initial levels. Thus, we may assume that these phosphorus removal methods do not te nd to change the NOM balance of the surface water. The findings in this study show that although NOM is removed by the phosphorus removal methods, specific ultraviolet (UV) absorbance (SUVA or SUVA 254 absorbance a t 254nm by the dissolved organic carbon (DOC) concentration of the water was not affected. The possibility of PhosX resin and alum sludge removing equal amounts of UV and non UV absorbing NOM fractions from the water is discussed. Moreover, it was established that the intermittent runs in the FITS successfully conserved NOM l evels closer to initial levels as compared to the continuous runs. NOM sustainability paves the way for continued application and further research of FITS with respect to a lum sludge and PhosX resin for phosphorus removal method

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14 CHAPTER 1 OVERVIEW Introdu ction Natural organic matter (NOM) is ubiquitous in surface waters and has a major impact on water chemistry. The properties of NOM in water are topics of significant environmental interest not only for aesthetic concerns such as color, taste and odor, b ut also for binding and transport of organic and inorganic pollutants; mediation of photochemical processes; carbon energy source for biota in biogeochemical processes ; and interactions with nitrogen, phosphorus and acidity. The composition of NOM is high ly variable depending on the sources of the organic material temperature and other factors such as pollutants added to water. In the present day scenario, increased industrial growth has caused continual overloading of pollutants such as phosphorus and nitrogen from agricultural drainage, municipal and industrial effluents and urban storm water run off into surface water bodies. Nutrient overloading from these point and non point sources can lead to eutrophication and decreased water quality. Under eut rophic conditions, algal blooms and hence depleted oxygen levels diminish the productivity of water bodies. Native aquatic flora and fauna suffers and water bodies can be rendered lifeless In order to address these issues, a phosphorus removal study was undertaken focusing on the beneficial reuse of waste byproduct materials These byproducts included iron slag and steel slag, fly ash, water treatment residuals and recycled concrete. Three commercial ion exchange resins were also tested for phosphorus removal and compared with the performance of the waste byproduct materials.

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15 After preliminary laboratory experiments, a floating island treatment system (FITS) was conceptualized and built to treat the eutrophic condition of s urface waters. This pilot scale testing in a natural surface water body (Lake Alice UF, Gainesville FL ) was used as a unique opportunity to study the accompanying changes in water chemistry. The focus of all laboratory and pilot scale experiments was to remove phosphorus; however, NOM and other water quality parameters were also measured. Thus, this research was undertaken to study the consequences of phosphorus removing processes on NOM concentration and chemistry As changes in NOM quality and quantity can have a direct impact on NOM fraction of water matrix it needed careful investigation and detailed analysis. The overall goal of this work is to profile changes in NOM as a result of different phosphorus removal processes. This has been achieved usin g jar tests, laboratory column tests, and a floating island treatment system. Both low cost materials and commercial ion exchange resins were tested for phosphorus removal from surface waters. This thesis will focus on the changes in the concentration and chemistry of NOM pertaining phosphorus removal methods. P hosphorus is bound to organic matter it is controlled by the changes in its quality. The hypothesis is that as NOM and phosphorus are closely associated due to their co existence in nature, and chan ges due to phosphorus removal can have an effect on the composition of NOM. Background and Significance Previous studies concerning the quantity of NOM in water show that observed increase in color and levels of NOM in fresh water sources is not solely due to the change in quantity of NOM. It has usually been greater than total organic carbon ( TOC ) content, indicating that not only the quantity but also the qualit y of NOM is changing

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16 (Lfgren et al., 2003) Fluxes of macronutrients, such as nitrogen and phosphorus, fr om soil to surface water is to a large extent controlled by this ever changing quantity and quality of NOM as these elements are bound to organic matter (Diaz et al., 2006) When water is treated to remove phosphorus, some research studies (Guan et al., 2006) show that as the concentration of phosphate increases, so does the adsorption rate on aluminum hydroxide surface as compared to NOM. However, humic acid is an exception to this phenomenon (Guan et al., 2006) This led to more research in NOM and phosphorus interactions in the surface water matrix to find that NOM species that contribute to total carbon storage like humic acid and fulvic acid (Pidou et al., 2008) compete with phosphorus for adsorption sites on goethite (Weng et al., 2008) The diverse origins of NOM in water can be largely due to urban storm water drainage (McCormick et al., 2009) It has been cited as the cause of increased levels of total phosphorus in the soil resulting in not only the loss of the abundant native periphyton community but also a shift in the dominant macrophyte species (McCormick et al., 2009) For example, this affects the dissolved oxygen levels and higher tropic levels in the Everglades. A substantial amount of work has been focused on the existing conditions of NOM in surface waters. The problem of eutrophication and various treatments methods have also been studied to treat the eutrophic condition of natural surface waters. However, ther e is a lack of research on the effects of phosphorus removal methods on NOM, especially at the pilot or field scale. This new work overcame limitations of previous studies where water quality indices of phosphorus spiked water were measured to confirm sust ainability of phosphorus removal methods. A floating island

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17 treatment system was set up to evaluate the NOM changes while removing phosphorus from surface water. Therefore, an insight into the effects of phosphorus removal methods on NOM characteristics is the focus of this project. Raw water sources susceptible to the present increase in color and NOM, represents a serious concern for water reservoirs around the world. Furthermore, changes in the characteristics of NOM may require an adjustment in NOM removal methods used by water treatment plants. In addition to the apparent aesthetic problem, a surge in the formation of potentially hazardous by products from disinfection methods, enhance the levels of both inorganic and organic pollutants by enhancin g mobilization from soi l (Boyer and Singer, 2005; 2008) and provide a substrate for undesirable microbiological growth in water distribution system s Moreover, changes in NOM properties (e.g. molecular size, hydrophobicity and biodegradability ) have a gr eat influence on the treatment efficiency (Mergen et al., 2008) In general, macromolecules are easier to remove than intermediate or small NOM molecules (Karanfil et al., 1996) but the latter may pose greater health risks. It has also been studied that in the presence of surfactants that NOM can increase the solubility of various h ydrophobic organic contaminants (Cho et al., 2002) The presence of various functional groups consisting of hydrophobic macromolecules in NOM can be identified and quantified to study their effects on the ecolog ical system. These hydrophobic macromolecules have significant ultraviolet (UV) absorbing characteristics such that they may be characterized using UV spectroscopy. Aromatic terrestrial compounds and chromophores can be studied and analyzed using UV absorb ance characteristics of NOM fractions (Esteves et al., 2009; Her et al., 2008; Ritchie and Perdue, 2003)

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18 Studies show that fluorescence spectroscopy and excitation emission matrices (EEMs) provide data to analyze origin and nature of NOM (Chen et al., 2003) Aquatic NOM and it s allochthonous or autochthonous origin can be categorized in respect with increased algal and biological activity in surface waters (Her et al., 2008) All this paved the way for the study of NOM quality with the help of UV and fluorescence spectroscopy along with monitoring its quantity. The effect of NOM on phosphorus treatment methods and vice versa is very crucial as NOM plays a very important role in maintaining water chemistry and ecological balance. In regards to ecological effects, the NOM changes are considered one of the most important ways that climate change will influence the aquatic biota (Steinberg, 2003) NOM is an important biogeochemical factor in the aquatic ecosystem as it is derived from nutrient cycling and consists of residual heterogeneous, hydrophilic, macromolecular compounds (i.e., h umic and fulvic compounds ) (Levine et al., 1997; Stumm and Morgan, 1996) In addition, increased run off intensities of NOM during wet season causes high soil NOM discharges (Temnerud et al., 2009) High temperature s in summer accelerate NOM degradation to enhance its mobility and possible precipitation. Abundant and strong solar energy obvious in such climate and thriving microbial activity also contribute to varying the composition of NOM (Scully et al., 2003) To develop future techniques to purify water and maintain sustainable ecosystem s, it is important to study NOM characterization and changes in its quality. It is apparent that the change in NOM is a consequence of changes in several factors: climate, anthropogenic atmospheric deposition, land use, and various in lake processes. Manag ement of water resources is largely dependant of tracking effects of

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19 water treatment technologies and changing NOM. It is important to understand the links between environmental changes and their impacts. This study was undertaken as a n increase in NOM an d a change in its quality will have significant impacts on numerous environmental conditions NOM is a vital energy source for microorganisms but on the other hand, much larger concentrations of NOM may also decrease the photic zone of surface waters. Transport and bioavailability of NOM bound organic pollutants can only be monitored with more research in this area. The environment is capable of coping with incessant evolution and fluctuations in the environmental condition; but when the changes occur too rapid, the biodiversity may be The challenge therefore lies in unraveling these multivariable effects and providing an insight into the surface water chemistry pertaining to NOM changes as a result of phosphorus removal techniques.

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20 CHAPTER 2 MATERIALS AND METHOD S Surface Waters Experiments were conducted with surface water from Lake Jesup and one of its tributaries, the Sanford Avenue Canal. Lake Jesup is located near the city of Sanford in central Florida and is part of the St. Johns River. Lake Jesup is impaired by high concentrations of total phosphorus (TP), total nitrogen (TN), unionized ammonia, and low concentrations of dissolved oxygen (FDEP, 2003) Lake Jesup and its tributaries are also rich in organic material. Figure 1 shows a map of Lake Jesup and a detail of the sampling locations. All samples were collec ted by the St. Johns River Water Management District (SJRWMD) and delivered to the Department of Environmental Engineering Sciences at the University of Florida. S amples were stored at 4C under dark conditions upon receipt. Samples were collected three di fferent times in 2009. Seasonal differences in water quality and differences in water quality for the two sample locations will be discussed in a subsequent section. A third site for collecting sample was Lake Alice, located in the University of Florida c ampus. It was chosen as the pilot site for conducting the phosphorus removal study. Extensive work to analyze and measure NOM levels of Lake Alice showed comparable results as that of Lake Jesup and its tributaries. This site was chosen due to its close pr oximity to the research group, which facilitated enhanced monitoring and rigorous daily sampling schedules. Seasonal d ifferences in water quality for the sampling location will be discussed in a subsequent section.

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21 Materials Two classes of materials were studied: low cost materials (LCMs) and engineered materials LCMs like alum sludge (AS), ferric sludge (FS), iron slag (IS), steel slag (SS), fly ash (FA), recycled concrete (RC) are waste by products and natural materials like limestone (LS). The LCM s were crushed in a mortar and pestle and sieved through U.S. Standard sieves 30 40 to give a particle size range of 420 FS LS and RC were dried under ambient laboratory conditions before crushing. FA which is a powder, was used as received. Thi s media was chosen on the basis of studies which show that Fe and Al oxides show faster adsorption kinetics than those of Ca and Mg (Guan et al., 2006) The low cost materials were weighed as dry material ranging from 1 16 g. The engineered materials studied in this work were commercial ion exchange resins and polymeric adsorbents, which are designed for municipal and industrial water treatment. Ion exchange resins like PhosX MIEX, and Dowex22 are engineered materials, and w ere used to compare with LCMs. The engineered materials were used as received and stored in deionized (DI) water. They were measured using a graduated cylinder with doses ranging from 1 8 mL of wet settled resin All materials were analyzed following stand ard jar tests procedures, as described in the next section. Jar Test Procedure Standard jar tests were conducted using a Phipps and Bird PB 700 jar tester at ambient laboratory temperature (20 22C) to investigate phosphorus removal efficiencies by the mat erials. Water samples were collected from Sanford Avenue Canal and Lake Jesup from January to April 2009. Two liters of Lake J esup or Sanford Avenue Canal water were added to each jar. Various doses of LCMs or engineered materials were measured and added t o each jar. C onstant mixing speeds of 100 rpm for

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22 AS FA, and engineered materials, and 200 rpm for r ecycled concrete, LS IS SS and FS was used as these materials were denser. All jar tests were conducted for 60 minutes, with samples collected after 5 m in mixing (no settling), 30 min mixing (no settling), and 60 min mixing (with 30 min undisturbed settling). All material doses were tested in duplicate. All results are average values of duplicate samples, unless noted otherwise. Raw water and treated wate r samples were measured for pH t otal organic carbon (TOC) and total n itrogen (TN). Samples were also analyzed for inorganic anions, ultraviolet absorbance at 254 nm ( UV 254 ) and fluorescence excitation emission matrices (EEMs) after filtering through a (Boyer and Singer, 2008) All glass sample containers were soaked overnight in a 6% nitric acid bath, rinsed three times with DI water, and air dried. Jar test paddles and jars were washed with laboratory detergent and DI water, ri nsed six times with DI water, and air dried. Plastic sample containers used for sampling were not reused. Column Test Procedure The concept of laboratory column test experiments, (Mortu la and Gagnon, 2007) was studied to set up a fixed bed column. The column was filled with 1 mL of wet material. A tubing arrangement was made to facilitate upward flow. A flow rate of 2 mL/min was used, preset by using DI water as source water and the outflow was measured in a graduated cylinder. 1 mL was equal to 1 bed volume (BV) as 1 mL of material was used. The system was set up for a flow rate of 2 BV/min Water samples were collected from Sanford Avenue Canal and Lake Alice from April to August 20 09 and September to December 2009. The system was pre washed with 120 BV of DI water and then pre filtered raw water was run on a continuous flow basis and a 12 hour

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23 on/12 hour off basis. 1 hour samples were taken in 125 mL flasks every 3 hours and left to flow for 12 hours during the night or to rest for 12 hours respectively. A breakthrough concentration of 50% removal was considered and confirmed after collecting and analyzing the samples. The water quality of raw water before and after filtration and al l other samples were for orthophosphate (OP) TP, UV 254 TOC, TN, anions, and pH. Each time a new batch of water was received, and a continuous flow experiment was performed using the most promising materials in order to create a reference for comparison. Floating Island Treatment System A floating island treatment system (FITS) was built and deployed on Lake Alice to compare with the jar tests and laboratory column tests. The FITS was powered by solar energy, and was developed as a combined research effort of physical chemical treatment units and biological treatment units. The biological treatment unit was placed first in order as it was found to be highly efficient in removing phosphorus from high phosphorus containing waters. This arrangement caused change in nature of NOM which will discussed in the later chapters. Two physical chemical treatment units; namely fluidized beds were used to compare the phosphorus removing capacity of two materials simultaneously. This arrangement also helped in reducing the headloss and energy requirements to pump water into treatment units. The dimensions of each fluidized bed was 6 inches in diameter and 24 inches in height. Both ends were covered with sediment shields in order to prevent the tr eatment materials from escaping. The beds were filled with 946 mL (0.25 gallons) of either AS or PhosX resin. The water from the biological unit was pumped upward at a rate of 0.5 gpm (2 BV/min) through each fluidized bed with a bilge pump for 10 12 hours per day

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24 and rested through the night. Pre and post treatment samples were collected as grab samples (sample collected instantaneously) on a daily basis at a particular time. A breakthrough concentration of 50% removal was considered and confirmed after c ollecting and analyzing a subsequent sample (Mortula and Gagnon, 2007 ) to replace exhausted fluidized beds with new ones. All graphs presented referring to the pilot study use real time data rather than C/C 0 values because significant changes in water quality were observed and it is easier to quantify the amount removed. Anal ytical Methods ACS grade or better chemicals were used to prepare all standard chemicals. Aqueous samples were analyzed as follows. An Accumet AP71 pH meter with a pH/ATC probe was used to measure pH. The pH meter was calibrated before each use with pH 4, 7, and 10 buffer solutions. Chloride, nitrate, and sulfate were measured on a Dionex ICS 3000 ion chromatograph equipped with Ion Pac AG22 guard column and AS22 analytical column. All inorganic anions were measured in duplicate with average values reported The relative difference between duplicate samples was considered to average the effects and confirm the results. It was observed that duplicate samples were in agreement to each other. UV 254 was measured on a Hitachi U 2900 spectrophotometer using a 1 cm quartz cell. Specific UV absorbance (SUVA or SUVA 254 DOC concentration of the water. SUVA was measured for all the water samples. Fluorescence EEMs were collected on a Hitachi F 25 00 fluorescence spectrophotometer using a 1 cm quartz cell. Samples were scanned at 5 nm increments over an excitation (EX) wavelength = 200 500 nm and at 5 nm increments over an emission (EM) wavelength = 200 600 nm. The raw EEMs were processed in MATLAB

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25 following published procedures (Cory and McKnight, 2 005) A DI water EEM, which was analyzed daily, was subtracted from the sample EEM; the area under the Raman scatter peak (EX = 350 nm) was calculated for DI water; intensity values of sample EEM were normalized by the area under the Raman scatter; and EEMs were plotted in MATLAB using the contour function with 20 contour lines. TOC and TN were measured on a Shimadzu TOC V CPH total organic carbon analyzer equipped with a TNM 1 total nitrogen measuring unit and an ASI V auto sampler. All TOC and TN sample s were measured in duplicate with average values reported. The relative difference between TOC and TN duplicates was between <10% and <20%, respectively

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26 CHAPTER 3 RESULTS AND DISCUSSI ON Sources of NOM The characterization of NOM present in Lake J esup its tributary (Sanford Avenue Canal), and L ake A lice was motivated from the observations made during phosphorus removal studies. It was studied that a low OP/TP ratio (Table A 1 and A 2 ) indicates that P is largely incorporated into biomass or other carbon compounds of the NOM (Persaud, 2010) These studies provided an impetus for an extensive study of NOM. The water quality characteristics for Lake Jesup Sanford Av enue Canal and Lake Alice are summarized in Table A 1 and A 2 The three raw waters investigated showed different physico chemical properties. NOM concentration and chemistry are measured by TOC and SUVA, respectively A ll waters were of different TOC con tent. The overall order of higher TOC content was Sanford Avenue Canal > Lake Jesup > Lake Alice (Table A 1 and A 2 ). T he greater UV 254 absorbance for Sanford Avenue Canal water reflected the more highly colored nature of this water in comparison to Lake Jesup and Lake Alice water. NOM hydrophobicity was estimated based on SUVA, which provides a quick indication of the composition of NOM present in raw water. The high SUVA of Sanford Avenue Canal water was indicative of hydrophobic organic material. Lake J esup was characterized by moderate SUVA. The lower SUVA values of Lake Alice showed a tendency of containing more hydrophilic organic material. Waters containing SUVA values of <4 L /mg C m DOC have previously been defined as being dominated by hydrophilic compounds (Edzwald, 1993) More research has conf irmed that w aters with high SUVA values had higher concentrations of hydrophobic organic carbon than waters with lower SUVA values that were dominated by hydrophilic organic carbon

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27 (Liang and Singer, 2003; Singer and Liang, 2004) Moreover earlier studies show that the humic and fulvic acid fractions form a major part of the hydrophobic organic material present in the water (Leenheer and Croue, 2003) Seasonal trends showed increased biological activity from winter through spring. A decrease in SUVA was observed as organic matter of microbial origin increased in Lake Jesup with increased biological activity. O rlando Sanford area weather data showed an increase in temperature progressing through the sampling times a nd low rainfall (WUnderground, 2009) Sanford Avenue Canal was characterized by high concentration of TOC, and high SUVA. Lake Alice samples showed increases in TOC during a wet period Lake Alice collects storm water run of f from University of Florida resulting in accumulation of in contaminants in the wetland The fluorescence emission excitation spectra of all NOM were attributable to a continuum of organic molecules (Figure B 1). NOM fractions had EEM peaks located at different excitation and emission wavelength pairs. For example, both contour graphs in Figure B 1 had two EEM peaks associated with longer emission wavelength and shorter excitation wavelengths. EEM analysis provides more data than single emission spectra EEM spectra for Lake Jesup and Sanford Avenue Canal are presented in the Figure B 1. The Lake Jesup water exhibited EEM features similar to those of Sanford Avenue Canal Water. The peaks of the contour graphs are at about emission wavelength 450 nm and e xcitation wavelength of 260 nm, which is characteristic of containing humic like fractions of NOM. A smaller peak at emission wavelength greater than 450 nm and excitation wavelength less than 250 nm represents the fulvic acid like fraction of NOM

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28 (Chen e t al., 2003) Both sets of data have a similar shape, but in Sanford Avenue Canal the wavelength intensity is much higher showing the presence in greater amounts of humic acid like and fulvic acid like fractions of NOM (Cory and McKnight, 2005) The presence of higher proportions of hydrophobic, humic and fulvic acid like fractions of NOM, in Sanford Avenue Canal water is attributable to its access to terrestrial source of plant material. Being a tributary of Lake Jesup Sanford Avenue Canal collects various types of organic matter along its path into Lake Jesup Lake Jesup has low proportions of organic matter fractions derived from terrestrial source as compared to Sanford Avenue Canal. J ar T est s Jar tests were conducted to evaluate phosphorus removal from Lake Jesup and Sanford Avenue Canal (Persaud, 2010) This section will show the results of secondary changes in water quality as a result of using LCMs and ion exchange resins. As t he Sanfo rd Avenue Canal wa ter was found to have higher OP/TP ratio than Lake Jesup all LCMs and ion exchange resins were tested in jar tests using Sanford Avenue Canal water to evaluate phosphorus removal. This section tracks changes in pH; TOC, UV, SUVA, and EEMs; chloride and su lfate; total nitrogen. As shown in Figure B 2, while removing phosphorus from the water the pH was continuously monitored and compared with the treated water for all LCMs that were used. It was observed that unlike some LCMs like SS, FA, and RC, all other materials maintained the pH close to the initial pH of the raw water. AS and FS decreased the pH by < 0.5 units as aluminum and iron hydrolysis reactions are expected to decrease pH. Amongst the ion exchange resins, PhosX resin and MIEX kept the pH of the water close to the initial value of pH of the raw water.

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29 In natural water samples, inorganic ions such as sulfate, can cause interferenc es at 210 nm (Her et al 2008). Moreover smaller molecular weight organic components are difficult to interpret as their peaks overlap with inorganic constituents. The nonaromatic functional groups in NOM show absorption maxima at shorter wavelengths (for example, non conjugated carboxyl ic acid and esters at 206 nm and amides at 210 nm). To determine the presence of aromatic functional groups, samples were analyzed at 254 nm. A wide range of wavelengths is observed between 250 nm to 295 nm to identify the aromatics in the B band or the be nezoid band (Esteves et al., 2009; Her et al., 2008) .These absorption wavelengths vary with the substituents in the benezene ring. Figure B 3 shows the rate of remov al of UV 254 absorbing substances from Sanford Avenue Canal water for LCMs and ion exchange resins. AS showed the greatest rate of UV 254 removal among the LCMs. From the observations in Figure B 3 it can seen that AS steadily removes UV 254 absorbing materia ls, and MIEX resin consistently showed the greatest rate of UV 254 removal among the ion exchange resins. Both materials AS and MIEX resin showed the greatest removal of UV 254 at 60 minutes. Overall LCMs show poor removal of UV 254 absorbing materials with A S showing a maximum removal of 50%. Better performance of AS may be attributed to increased adsorption sites due to incorporation of powdered activated carbon (PAC) from the water treatment plant. Consequently larger quantity of NOM fractions are removed b ecause of enhanced capability of AS. All other resins show a maximum removal at 30 minutes and thereafter a steady uptake of UV 254 absorbing materials. Being ion exchange resins, PhosX and Dowex22 may be initially removing UV 254 absorbing fractions of NOM. However later the targeted constituent namely; phosphorus may have been preferentially removed over

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30 NOM as these resins are industrially designed to remove phosphorus from water. M IE X resin being a good removing agent for DBP precursors (UV 254 absorbing materials) {Bolto et al. 2002; Boyer and Singer 2005 2006 2008 ) shows a substantia l removal of UV 254 absorbing materials at 30 minutes TOC is the most comprehensive measurement used for quantification of the presence of NOM in aquatic systems. As organic contaminants represent insignificant fraction of the TOC, it is synonymous to NOM. TOC may be subdidvided into dissolved organic carbon (DOC) and particulate organic carbon (POC). A small percentage of about less than 10% of the TOC is represented by the POC (Thurman, 1985) Concentration of partic ulate fraction of organic carbon rises in the water with increase in its flow rate. Seasonal changes affect the concentration of POC as run off from urban areas and farmlands increase. Algal blooms in water bodies show a rise in the TOC content in the wate r. DOC is influenced by all spatial and temporal variations. LCMs and ion exchange resins show removal of NOM from the water samples. This removal may vary depending on spatial and temporal variations of water. LCMs remove dissolved constituents from water based on the principle of adsorption whereas ion exchange resins follow the principle of ion exchange mechanisms. Figure B 4, shows change in TOC and SUVA following phosphorus treatment. SUVA remained relatively constant following treatment. MIEX resin removed a substantial fraction of TOC. This can be confirmed with the help of previous studies which show MIEX resin removes hydrophobic fractions of NOM from raw water (Mergen et al., 2008) Removal of hydrophobic fractions of NOM (i.e., UV 254 absorbing fractions) should therefore lower the SUVA. For example, it may be observed that 1 mL/L MIEX

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31 resin decreases the TOC to about 10 mg C/L but does not show decrease in SUVA as predicted. However a higher dose of MIEX resin at 4 mL/L reduced the TOC from 18 to 3 mg C/L and also displays lowering of SUVA as predicted. From the NOM removal trends obser ved it may be assumed that at low doses MIEX resin removes non UV 254 absorbing fractions of water wheras with a higher dose it removes more of the hydrophobic fraction of NOM in water. High SUVA waters are enriched with hydrophobic NOM like humic substance s. SUVA being an indicator of the presence of aromatic compounds can help characterize the NOM at a given location (Leenheer and Croue, 2003) LCMs like SS and RC show minor NOM removal and follow similar decrease in SUVA. IS and LS displayed slight increase in TOC and a respective rise in SUVA. This may be due to possible contamination of LCMs ob tained from the industry and quarry respectively. Both AS and FS were received from water treatment plant residuals. These materials had powdered activated carbon (PAC) incorporated in it to enhance the coagulation treatment methods in water treatment plan ts (Persaud, 2010) AS with more active surface area due to presence of PAC in it (Tomaszewska et al., 2004; Uyak et al., 2007) showed removal of NOM and subsequent decrease in SUVA. However, FS along with PAC in it failed to behave as predicted and did not remove NOM due to increased adsorption sites in its PAC. It showed an undesirable increase in TOC levels that ma y be attributed to large proportion of carbon contaminants in it from water treatment plant methods. Based on previous studies on fluorescence EEMs as summarized in Table s A 3 and A 4 the presence of various NOM fractions in water can be identified. It ha s been studied that hydrophobic fractions of NOM quantifiably increase the overall fluorescence

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32 than its basic and hydrophilic fractions. Various electron donating groups such as amines and hydroxyl groups may increase fluorescence properties of NOM presen t in surface water. Based on the EEMs in Figure B 5 PhosX resin removes less humic and fulvic acid fractions of NOM from Sanford Avenue Canal water. AS acts as an adsorbent and has more available sites for adsorption on account of incorporation of PAC in i t This enhanced surface area allows the uptake of larger molecules of humic and fulvic acids like NOM fractions from the water. At an emission wavelength of about 520 nm small peaks of soil humic like substances can be identified in AS treated water. It i s interesting to note that PhosX resin removes a small fraction of soil humic component from NOM in water but retains the aquatic humic and fulvic acid like fractions of NOM in treated water of Sanford Avenue Canal. Figure B 6 shows the change in chloride and sulfate following the 60 minute treatment of Sanford Avenue Canal water. There was no change in chloride by any of the LCMs. AS and FS increased the sulfate by a factor of 2 3. This is because AS and FS are aluminum sulfate and ferric sulfate, and were used to coagulate water at water treatment plants. It was interesting to note that AS, which at this stage of study was being considered as a potential candidate for good phosphorus removing agent was adding sulfate to treated water. This finding is cruci al as presence of excess of sulfate ions can cause interference at low UV 254 absorption wavelengths of about 210 nm. This wavelength essentially helps indicate the presence of aromatic compounds in NOM (Esteves et al., 2009; Her et al., 2008) MIEX and Dowex22 resins added chloride to the water and removed the sulfate, as would be expected for a true ion exchange resin (Blaney et al., 2007; Bolto et al., 2002) PhosX resin was observ ed to be removing both

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33 chloride and sulfate. This observed behavior of PhosX resin may be categorized partly as adsorption. To investigate the potential of nitrogen removal from nutrient polluted water, the LCMs and ion exchange resins were evaluated. Exc ess nitrogen similar to phosphorus, can contribute to eutrophication and deterioration of water quality. Thus, the effect of LCMs and ion exchange resins was analyzed for nitrogen removal in comparison to phosphorus removal. Figure B 7 shows that AS, SS, R C, and LS removed 31 34% TN. FS and IS resulted in an increase in TN. All ion exchange resins removed greater than or equal amounts of TP relative to TN (Persaud, 2010) It can be concluded that recycled concrete and ion exchange resins can remove both TP and TN. The average nitrogen removal rate was not as high as phosphorus removal rates. Moreover nitrogen assimilation rate by wetland plants may be moderate enough t o control nitrogen as a pollutant in surface water (Zhou and Hosomi, 2009) It has also been studied that nitrogen contained in the wetland plants is often higher than the total amount of nitrogen removed from influent by other engineered methods. This suggests that plant uptake may be a major pathway for nitrogen removal of polluted river water. Laboratory Column T est s The jar tests showed that AS and PhosX resin were two of the best performing materials for phosphorus removal. As a result, laboratory column tests were conducted to furthe r evaluate the phosphorus removing capabilities of the materials. Continuous flow treatment As shown in Figure C 1, while removing phosphorus from the water the pH was continuously monitored and compared with the treated water for AS and PhosX resin. It w as observed that the pH of the water was lowered and raised by AS and PhosX resin,

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34 respectively, and then maintained close to the natural pH of the water. AS decreased the pH as aluminum hydrolysis reactions are expected to decrease the pH. PhosX resin kep t the pH 0.5 units greater than initial pH of the raw water where as AS kept it balanced close to pH 7.5. Quantification of the presence of the organic matter in aquatic systems was done with help of measuring the TOC in the water. DOC contributes to a do minant part in TOC and can be assumed to be same for broad analysis of NOM (Leenheer and Croue, 2003) Figure C 2 shows the change in TOC following the continuous treatment of Sanford Avenue Canal water. It showed an unpredicted decrease in TOC levels initially that may be attributed to change in raw water characteristics through the duration of t he experiment. The TOC in the Sanford Avenue Canal April water was in the range of 14.4 to 14.6 mg/L. When the phosphorus removing capacity of AS and P hos X was being tested, the TOC of the water for the first sample point was reduced by 40% and 30%, respec tively. Thereafter the TOC was maintained close to initial levels. From Figure C 2, it is observed that after the first sample point the treatment method holds the natural levels of the water. This deviation may also be attributed change in the influent wa ter quality as the raw water standards were checked only at the beginning and end of the experiment. It is interesting to note that with continuous column test experiments AS and PhosX resin exhibit similar trends for NOM removal where PhosX resin removes more TOC than AS. Removal of TOC by AS can be partly attributed to its greater available adsorption sites owing to the presence of PAC in it. It appears that upon continuous treatment the adsorption sites are unable to hold the large NOM

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35 molecules as studi ed in jar test results. PhosX was consistent showing only slight removal of NOM and delivered excellent performance in removing phosphorus Following the trend projected in TOC removals by AS and PhosX resin the trends of UV 254 absorbing materials may be s tudied. Similar to the Figure C 2, it has been observed in Figure C 3 that the after the first sample point the trend line is seen to be steady. It appears that there is almost no removal of UV 254 absorbing compounds by AS predicted on account of continuous exposure to dissolved constituents of water. It may be assumed that larger molecules of NOM lost in the competition of adsorption to smaller molecules of phosphorus. These phosphorus removing ma terials retain the proportion of UV 254 absorbing compounds in the NOM of water. Presence of anions such as chloride is high as 161 to 198 mg/L. Both the materials being used to remove phosphorus pose no threat the chloride levels in the treated water as sh own in Figure C 4 Although PhosX resin is an ion exchange resin, it is not observed to be exhibiting true ion exchange properties. Thus it does not add to the chloride content of the water. AS, which is actually alum inum sulfate used a s a coagulant i n a surface water treatment plant adds sulfate to the water in the first sample point where as P hos X resin shows 60% removal as studied in jar test result in figure B 5. T hereafter both the materials steadily maintain the s ulfate le vels close to the natural l evel (Figure C 5). A sustained level of sulfate ions in the water and deviation in the initial part of samples could be due to washing away of sulfate under continuous flow column studies. This indicates that when the effect of AS on UV absorbing fractions of NOM is further studied, the presence of sulfate ions in AS will probably not interfere with those UV absorbing fractions of NOM. This will allow a sustainable use of AS in

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36 future phosphorus removal studies. This effect was not observed in the prelimin ary jar test studies as same water was contained in the jars whereas column test setup adopted a continuous flow pattern. Intermittent flow treatment Studies showed that a 12 hr resting time improved phosphorus removing capacity of the materials (Persaud, 2010) This perfectly agreed with a real world scenario where the system would be running for a 12 hr span in the daytime and shut off for the 12 hr span i n the nightime. This arrangement of 12 hr on and 12 hr off (12/12) was adopted and samples from L ake A lice in August were run to study their effects on the NOM. Frequent sampling and ease of handling and tranport of intesive daily samples allowed us to c hoose this sampling site. The water characteristics are listed in Table A 1 and A 2 It was recognized with c areful scrutiny that a 12 hr rest for the materials improved its phosphorus removing capacity and thereby enhanced its capability to conserve the N OM content in the water. A high removal in phosphorus can lead to low or almost no removal of NOM. A reduction in NOM removal rate was observed for both AS and PhosX resin (Figure C 6). From careful observation it may be analyzed that the average removal o f NOM for AS and PhosX resin may be similar. However 12/12 run presents a unique oppurtunity to study the exhibition of alternating elevations and depressions corresponding to two consecutive 12 hr on run times with a 12 hr off rest period in between. This 12/12 arrangement proved perfect as it only improved phosphorus removals while maintaining the NOM in the water. As seen in the continuous run, PhosX resin still removed NOM more than AS by a small factor. The SUVA of the water did not show major deflecti ons and lay in the range of 2.5 to 3 L/mg C m (Figure C 7). Although PhosX resin projected decrease of TOC the corresponding

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37 data points of SUVA levels did not show a deacrease. This phenomena may be summarized as PhosX resin removes equal proportion of U V and non UV absorbing materials from the suraface water of L ake A lice. Comparison of continuous and intermittent flow A comparative study was considered for further research to examine the variation in effect on quantity and quality of NOM between continuous and 12/12 runs. Both the phosphorus removing materials, AS and PhosX resin removed more NOM in continuous runs than in the 12/12 runs. We may summarize that the 12/12 runs are better at conserving NOM in natural waters (Figure C 8 and C 10). Although TOC levels were higher in the 12/12 run, the SUVA was lower than the continuous run (Figure C 9 and C 11). Comparative s tudy of 12/12 and continuous run provides us with a finding that both AS and PhosX resin remove more UV 254 absorbing NOM fractions from water. Floating Island Treatment System Laboratory scale 12/12 column test experiments were transformed into a real wor ld floating island treatment system for pilot scale testing. With the help of Dr. at the University of Florida, a biological unit was mounted along with a physical chemical unit on a floating island to treat and remove phosphorus from L ake A l ice water. The introduction of the biological unit as a predecessor to the physical chemical treatment unit provided a unique opportunity to study the NOM changes in water after biological treatment. Table s A 1 and A 2 show that water quality parameters of L ake A lice and Sanford Avenue Canal are comparable. Interestingly in the FITS, the biological (Bio) treated water which was an influent to the successive AS and PhosX resin columns lowered the pH range of the water (Figure D 1). As observed in the prelimi nary studies of jar tests and further analysis of

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38 data in column test experiments reaffirms that AS and PhosX resin lowers the pH of the water by 1 to 2 units than the influent raw water. Both AS and PhosX resin lower the pH of the treated water to a range of 7 to 8 from a range of 7 to 9 of the influent Bio water. With the varying TOC levels of the raw water the influent Bio water also varies the TOC content in the water (Figure D 2). Seasonal changes also affected the surface water quality of water, which in turn was reflected in the treatment studies. Moreover, as L ake A lice collects storm water run off from the University of Florida the water quality of the lake gets affected by the varying organic material. As studied during our course of experiments fr om jar tests to column tests, AS removes less TOC than PhosX resin, similar trends have been identified in the floating island treatment system. The TOC content of the Lake Alice raw water keeps varying with seasonal changes (Figure D 3). The Bio water var ies with respect to changes in raw water as well as due to its own removal mechanism. PhosX resin treated water owes its influent TOC to the Bio water. PhosX resin removes NOM, measured as TOC content to range of 4 to 6 mg/L with occasional spikes observe d in case of algal bloom in the lake waters. As seen in Figure D 4, the SUVA for Lake Alice water, Bio water, and AS treated water is close to 2.5 L/mg C m whereas SUVA for PhosX resin treated water is lower by 0.5 L/mg.cm. It may be summarized that PhosX resin removes more of non UV 254 absorbing fractions of NOM while removing NOM from water. Algae bloom is one of the most significant causes of water quality problems. This can occur in lakes, rivers, ponds and coastal waters. High levels of organic matte r, nitrogen and phosphorus in water can cause an algae bloom. These nutrients can come from urban sources like wastewater treatment facilities and runoff from fertilized

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39 lawns. Agricultural practices can add to the nutrient load of a watershed via runoff from fertilized croplands and animal feedlots. When the plants and algae die and undergo bacterial decomposition, dissolved oxygen is removed from the water by the rapidly multiplying bacteria. Lowered oxygen levels and reduced vegetation make it difficul t for other aquatic organisms, including fish, to survive. The excessive growth of algae can also cause taste and odor problems that make water undesirable. In addition, the unsightly and odorous mats of green scum can have a negative impact on water recre ational options The pH of the water goes typically high, which was observed as pH 10 at the peak of the algae bloom (Foott et al. 2009) Increase in pH and increase algal activity led to increase in TOC levels as seen in Figure D 4. As shown in Figure D 5, SUVA for Bio water tracks the SUVA of the Lake Alice water. Undesirable spikes and dips of SUVA are observed during algae bl oom period.

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40 CHAPTER 4 SUMMARY AND CONCLUSIONS The overall goal of this work to characterize NOM and track the changes in its quantity and composition was successfully completed while removing phosphorus from surface water. Jar tests were used at the preliminary level to screen and select the promising candidates, namely AS and PhosX resin for phosphorus removal among v ario us LCMs and ion exchange resins. Further laboratory scale column experiments conducted to test the sustainability of these materials exhibited maximum phosphorus removal and no significant effect of NOM. A FITS built to test the hypothesis of lab scale column test achieved a lake variant TOC of treated water and a constant SUVA. The secondary changes on water quality on NOM were studied for each of the three types of tests mentioned above. The major conclusions in each stage of this study are listed as follows: Phos X resin and AS were chosen as best materials for phosphorus removal and had similar TOC removals. These materials had no effect on chloride while AS increased the sulfate levels. MIEX removed higher quantities of NOM and thus should not be considered a candidate for maintaining NOM levels while removing phosphorus from surface waters. Thus j ar test screeni ng process was successful in evaluating these economical phosphorus removing materials for sustainable use in treating surface waters. PhosX resin and AS was utilized for prolonged time intervals for phosphorus removal from surface waters. The continuous flow of water led to a decrease in NOM removal capacity of AS and hence may be utilized in further NOM conserving phosphorus removal studies. PhosX resin removes more of non UV 254 absorbing fractions of NOM while removing NOM from water.

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41 Larger hydroph obic UV 254 absorbing fractions, which are significant in transport and bioaccumulation of various contaminants, are being removed by phosphorus removal methods. NOM removals accompanied by constant SUVA levels shows that PhosX resin and AS removed equal amounts of UV and non UV absorbing NOM fractions from the water. AS and PhosX resin removed maximum phosphorus and conserved NOM and retained its balance of UV and non UV absorbing fractions of NOM in water. Thus, this proves that these phosphorus removal methods do not tend to change the NOM balance of the surface water. NOM sustainability in this work paves the way for continued application and further research of FITS with respect to AS and PhosX resin for phosphorus removal methods. Future Work : A few approaches to further this line of work are listed below. UV ratio index (URI) =UV 210 /UV 254 should be evaluated to identify the increase of eutrophicity, increased oxidation and microbial activity ( double bon ds in carbon ) in surface waters. Quantification of fluorescence EEM and Fourier transform infrared must provide help in characterization of nature and distribution of functional groups in NOM. Extensive research will lead to trac ing terrestrial or aquati c microbial origin with the help of the above techniques. UV absorbance of PhosX resin and AS treated waters has been observed to be following orthophosphate removal trends. Further research in phosphorus fractions present in biomass should provide an ins ight to this characteristic trend. XAD resin fractionation must be used to quantify proportions of non UV absorbing, hydrophobic compounds, which SUVA cannot show. A molecular distribution study would further present a complete picture to compare molecul ar weights of UV absorbing compounds.

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42 APPENDIX A CHARACTERIZATION OF NOM Table A 1. Water quality characteristics for Lake Jesup and Sanford Avenue Canal Month pH Turbidity TOC SUVA Cl SO42 NO3 TN OP TP OP/TP 2009 NTU mg C/L L/mg Cm mg/L mg/L mg N/L mg N/L g P/L g P/L Lake Jesup January 7.02 2.86 16.1 3.8 109 23.9 < 0.5 1.0 17.2 111 0.15 March 7.33 15.8 17.3 2.9 175 35.6 < 0.5 1.3 7.3 206 0.04 April 7.40 22.3 17.8 3.2 269 57.1 < 0.5 0.7 5.6 274 0.02 Sanford Avenue Canal January 7.14 2.47 23.2 4.8 122 22.6 0.6 1.2 86.2 137 0.63 March 7.67 3.70 18.3 4.4 188 40.6 0.6 0.9 159 194 0.82 April 7.63 4.18 14.8 4.3 197 35.3 0.7 0.1 232 289 0.80 Table A 2 Water quality characteristics for Sanford Avenue Canal and Lake Alice Month Form pH Turbidity TOC SUVA Cl SO42 NO3 TN OP TP OP/TP 2009 NTU mg C/L L/mg Cm mg/L mg/L mg N/L mg N/L g P/L g P/L Sanford Avenue Canal April Raw 7.59 4.18 14.44 4.44 185.15 33.02 1.28 221.78 329.07 0.67 Filt. 1 7.74 14.58 4.07 185.15 33.02 1.28 1.22 215.23 250.30 0.86 June Raw 6.93 33.56 4.86 54.51 6.30 9.38 0.84 107.10 195.11 0.55 Filt. 1 7.57 31.48 5.22 54.51 6.30 9.38 0.84 107.10 142.95 0.75 Lake Alice (LA) July Raw 7.70 7.16 3.19 13.67 18.70 0.49 421.26 481.69 0.87 Filt. 1 7.70 7.08 3.09 13.6 18.3 <0.5 0.44 387.12 423.43 0.91 August Raw 7.55 8.26 2.72 15.86 20.76 1.95 506.90 528.85 0.96 Filt. 1 7.50 8.06 2.83 0.59 372.37 327.27 0.83 1 Sample filtered through a Whattman GF/A Filter

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43 Table A 3. Quantification of EEMs f luorescence (Chen et al., 2003) Type Region Wavelength Aromatic protein i (tyrosine) Region 1 Short excitation wavelength(<250nm) Short emission wavelength(< 330nm) Aromatic protein ii (waste water components in estuaries) Region 2 Short excitation wavelength(<250nm) Short emission wavelength(<380nm) Fulvic acids (hydrophobic acids) Region 3 Excitation wavelength(<250nm) Emission wavelength(>380nm) Soluble microbial byproduct materials (tryptophan or protein like) Region 4 Intermediate excitation wavelength(250 280nm) Short emission wavelength(<380nm) Humic acids (marine humic acids etc.) Region 5 Short excitation wavelength(>280nm) Short emission wavelengt h(>380nm) Table A 4 Major fluorescent components in EEM (Esteves et al., 2009) Emission wavelength (nm) Excitation wavelength (nm) NOM fraction 320 350 270 280 Typtophan like, protein like or phenol like 380 420 310 320 Marinehumic like 380 480 250 260 Humic like 420 480 330 350 Humic like

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44 APPENDIX B JAR TESTING FIGURES A B Fig ure B 1. Fluorescence EEMs for ( A ) Lake Jesup and ( B ) Sanford Avenue Canal water samples from March 2009

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45 A B Figure B 2 Change in pH following 60 min of treatment of Canal water by (A ) ion exchange resins and ( B ) low cost materials A B Figure B 3. Rate of removal of UV 254 absorbing substances by ( A ) ion exchange resins dosed at 1 and 4 mL/L and ( B ) low cost materials dosed at 4 g/L in Sanford Avenue Canal water. Initial UV 254 = 0.81 1.04 cm 1

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46 A B Figure B 4. Change in TOC and SUVA following 60 min of treatment by (A ) ion exchange resins and ( B ) low cost materials. TOC FS = 34.6 mg/L.

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47 A B Figure B 5. Fluorescence EEM s for Sanford Avenue Canal water treated with (A) AS dosed at 4mg/L, (B) PX dosed at 2mL/L.

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48 Fig ure B 6. Change in chloride and sulfate following 60 min of treatment of Sanford Avenue Canal water by ( A ) ion exchange resins and ( B ) low cost materials ion exchange resins. Initial chloride = 112 191 mg/L; initial sulfate = 22.5 40.6 mg/L.

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49 Fig ure B 7. Total Nitrogen remaining after 60 min of treatment of Sanford Avenue Canal water by ( A ) ion exchange resins and ( B ) low cost materials ion exchange resins. Initial TN = 0.81 1.43 mg N /L. 0.0 0.2 0.4 0.6 0.8 1.0 1.2 PX (1) MX (1) DX (1) *PX (4) MX (4) DX (4) C/C 0 Ion exchange resins (mL/L)

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50 APPENDIX C COLUMN T ESTING FIGURES Figure C 1. Change in pH following column test of Sanford Avenue Canal April water by AS and PX. Figure C 2. Change in TOC following column test of Sanford Avenue Canal April water for AS and PX. 6.0 6.5 7.0 7.5 8.0 8.5 9.0 0 1000 2000 3000 4000 5000 6000 7000 pH Bed Volumes AS (April) PX (April) 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 0 1000 2000 3000 4000 5000 6000 7000 TOC C/C 0 Bed Volumes AS (April) PX (April)

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51 Figure C 3. Rate of removal of UV 254 absorbing substances following column test of Sanford Avenue Canal April water for AS and PX Initial UV 254 = 0.576 0.612 cm 1 Fig ure C 4. Change in chloride following column test of Sanford Avenue Canal April water for AS a nd PX. Initial chloride = 169 198 mg/L 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 0 1000 2000 3000 4000 5000 6000 7000 UV 254 C/C 0 Bed Volumes AS (April) PX (April) 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 0 1000 2000 3000 4000 5000 6000 7000 Cl C/C 0 Bed Volumes AS (April) PX (April)

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52 Figure C 5. Change in sulfate following column test of Sanford Avenue Canal April water for AS and PX I nitial sulfate = 30 34.4 mg/L. Figure C 6. Change in TOC following 12 hr On 12 hr Off (12/12) column tests by PX and AS on Lake Alice August. Initial TOC = 8.1 mg/L as C. 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 0 1000 2000 3000 4000 5000 6000 7000 SO 4 2 C/C 0 Bed Volumes AS (April) PX (April)

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53 Figure C 7. Change in SUVA following 12 hr On 12 hr Off (12/12) column tests by PX and AS on Lake Alice August. Figure C 8. Comparison in change in TOC following Continous, 12/12 column tests for PX. Initial TOC (Continuous) = 7.1 mg/L as C; Initial TOC (12/12) = 8.1 mg/L as C.

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54 Figure C 9. Comparison in change in SUVA following Continous, 12/12 column tests for PX. Fig ure C 10. Comparison in change in TOC following Continous, 12/12 column tests for AS. Initial TOC (Continuous) = 7.1 mg/L as C; Initial TOC (12/12) = 8.1 mg/L as C.

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55 Figure C 11. Comparison in change in SUVA following Continous, 12/12 column tests for AS.

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56 APPENDIX D PILOT TESTING FIGURE S Figure D 1. Change in pH following FITS with LA water. Date from 10/10 to 10/19/2009. Figure D 2. Comparison of c hange in absolute values of TOC following FITS procedure for PX,and AS. Date from 10/10 to 10/19/2009.

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57 Figure D 3. Comparison of c hange in SUVA following FITS procedure for PX and AS. Date from 10/10 to 10/10/2009. Figure D 4. Comparison of c hange in TOC following FITS procedure for PX during entire study. 0 2 4 6 8 10 14 Sep 09 19 Sep 09 24 Sep 09 29 Sep 09 4 Oct 09 9 Oct 09 14 Oct 09 19 Oct 09 24 Oct 09 29 Oct 09 3 Nov 09 8 Nov 09 13 Nov 09 18 Nov 09 23 Nov 09 28 Nov 09 3 Dec 09 8 Dec 09 13 Dec 09 18 Dec 09 23 Dec 09 28 Dec 09 2 Jan 10 TOC mg/L C Dates LA Raw Bio PX

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58 Figure D 5. Comparison of c hange in SUVA following FITS procedure for PX during entire study.

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59 LIST OF REFERENCES Blaney, L.M., Cinar, S., and SenGupta, A.K., 2007, Hybrid anion exchanger for trace phosphate removal from water and wastewater: Water Research, v. 41, p. 1603 1613. Bolto, B., Dixon, D., Eldridge, R., King, S., and Linge, K., 2002, Removal of natural organic matter by ion exchange: Water Research, v. 36, p. 5057 5065. Boyer, T.H., and Singer, P.C., 2005, Bench scale testing of a magnetic ion ex change resin for removal of disinfection by product precursors: Water Research, v. 39, p. 1265 1276. Boyer T.H., and Singer, P.C., 2006, A pilot scale evaluation of magnetic ion exchange treatment for removal of natural organic material and inorganic ani ons: Water Research, v. 40, p. 2865 2876. Boyer, T.H., and Singer, P.C. 200 8 Stoichiometry of Removal of Natural Organic Matter by Ion Exchange: Environmental Science & Technology, v. 42, p. 608 613. Chen, W., Westerhoff, P., Leenheer, J.A., and Booksh, K., 2003, Fluorescence Excitation Emission Matrix Regional Integration to Quantify Spectra for Dissolved Organic Matter: Environmental Science & Technology, v. 37, p. 5701 5710. Cho, H. H., Choi, J., Goltz, M.N., and Park, J. W., 2002, Combined Ef fect of Natural Organic Matter and Surfactants on the Apparent Solubility of Polycyclic Aromatic Hydrocarbons: J Environ Qual, v. 31, p. 275 280. Cory, R.M., and McKnight, D.M., 2005, Fluorescence Spectroscopy Reveals Ubiquitous Presence of Oxidized and R educed Quinones in Dissolved Organic Matter: Environmental Science & Technology, v. 39, p. 8142 8149. Diaz, O.A., Daroub, S.H., Stuck, J.D., Clark, M.W., Lang, T.A., and Reddy, K.R., 2006, Sediment Inventory and Phosphorus Fractions for Water Conservation Area Canals in the Everglades: Soil Sci Soc Am J, v. 70, p. 863 871. Edzwald, J.K., 1993, Coagulation in drinking water treatment: particles, organics and coagulants: Water Science Technology., v. 27, p. 21 35. Esteves, V.I., Otero, M., and Duarte, A.C. 2009, Comparative characterization of humic substances from the open ocean, estuarine water and fresh water: Organic Geochemistry, v. 40, p. 942 950. FDEP, 2003, Middle St Johns Basin Group 2 Basin Status Report.

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60 Foott, J.S., Stone, R., and Fogerty, R., 2009, FY2006 Technical Report: Effects of simulated algal bloom pH on juvenile lost river sucker energetics and growth, U.S. Fish and Wildlife Service California Nevada Fish Health Center: Anderson, CA. Guan, X. H., Shang, C., and Chen, G. H., 2006, Co mpetitive adsorption of organic matter with phosphate on aluminum hydroxide: Journal of Colloid and Interface Science, v. 296, p. 51 58. Her, N., Amy, G., Sohn, J., and Gunten, U., 2008, UV absorbance ratio index with size exclusion chromatography (URI SE C) as an NOM property indicator: Journal of water supply : research and technology, v. 57, p. 35 44. Karanfil, T., Schlautman, M.A., Kilduff, J.E., and Weber, W.J., 1996, Adsorption of Organic Macromolecules by Granular Activated Carbon. 2. Influence of D issolved Oxygen: Environmental Science & Technology, v. 30, p. 2195 2201. Leenheer, J.A., and Croue, J. P., 2003, Aquatic Organic Matter: Environmental Science & Technology. Levine, A., Libelo, E., Bugna, G., Shelley, T., Mayfield, H., and Stauffer, T., 1997, Biogeochemical assessment of natural attenuation of JP 4 contaminated ground water in the presence of fluorinated surfactants: Sci Total Environ, v. 208, p. 179 95. Liang, L., and Singer, P.C., 2003, Factors influencing the formation and relative di stribution of haloacetic acids and trihalomethanes in drinking water.: Environment Science and Technology, v. 37, p. 2920 2929. Lfgren, S., Andersen, T., and Forsius, M., 2003, Climate induced water color increase in Nordic lakes and streams due to humus: Nordic Council of Ministry Brochure (12p). McCormick, P., Newman, S., and Vilchek, L., 2009, Landscape responses to wetland eutrophication: loss of slough habitat in the Florida Everglades, USA: Hydrobiologia, v. 621, p. 105 114. Mergen, M., Jeffe rson, B., Parsons, S.A., and Jarvis, P., 2008, Magnetic ion exchange resin treatment: Impact of water type and resin use: Water Research, v. 42, p. 1977 1988. Mortula, M.M., and Gagnon, G.A., 2007, Phosphorus adsorption by naturally occurring materials an d industrial by products: Journal of Environmental Engineering and Science, v. 6, p. 157 164.

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61 Persaud, A., 2010, Sustainable phosphorus removal from surface water, University of Florida. Pidou, M., Avery, L., Stephenson, T., Jeffrey, P., Parsons, S.A., L iu, S., Memon, F.A., and Jefferson, B., 2008, Chemical solutions for greywater recycling: Chemosphere, v. 71, p. 147 155. Ritchie, J.D., and Perdue, E.M., 2003, Proton binding study of standard and reference fulvic acids, humic acids, and natural organic matter: Geochimica et Cosmochimica Acta, v. 67, p. 85 96. Scully, N.M., Cooper, W.J., and Tranvik, L.J., 2003, Photochemical effects on microbial activity in natural waters: the interaction of reactive oxygen species and dissolved organic matter: FEMS Mic robiology Ecology, v. 46, p. 353 357. Singer, P.C., and Liang, L., 2004, Coagulation of natural organic material: effects on speciation of halogenated disinfection by products.: Water Science Technology. Steinberg, C., 2003, Ecology of humic substances i n freshwaters: determinants from geochemistry to ecological niches: Berlin, Springer, 440 p. Stumm, W., and Morgan, J.J., 1996, Aquatic chemistry : chemical equilibria and rates in natural waters: New York :, Wiley. Temnerud, J., Dker, A., Karlsson, S., Allard, B., Kohler, S., and Bishop, K., 2009, Landscape scale patterns in the character of natural organic matter: Hydrology and Earth System Sciences, v. 6, p. 3261 3299. Tennant, M.F., and Mazyck, D.W., 2007, The role of surface acidity and pore size d istribution in the adsorption of 2 methylisoborneol via powdered activated carbon: Carbon, v. 45, p. 858 864. Thurman, E.M., 1985, Organic Geochemistry of Natural Waters, Kluwer Academic Publishers Group, 610 p. Tomaszewska, M., Mozia, S., and Morawski, A.W., 2004, Removal of organic matter by coagulation enhanced with adsorption on PAC: Desalination, v. 161, p. 79 87. Uyak, V., Yavuz, S., Toroz, I., Ozaydin, S., and Genceli, E.A., 2007, Disinfection by products precursors removal by enhanced coagulation and PAC adsorption: Desalination, v. 216, p. 334 344. Weng, L., Van Riemsdijk, W.H., and Hiemstra, T., 2008, Humic Nanoparticles at the Environmental Science & Technology, v. 42, p. 874 7 8752.

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62 WUnderground, 2009, Weather Underground. Zhou, S., and Hosomi, M., 2009, Nitrogen removal from polluted river water by surface flow wetland with forage rice (Oryza sativa L. cv. Kusahonami): International Journal of Environmental Engineering, v. 1, p. 123 135.

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63 BIOGRAPHICAL SKETCH Poulomi Banerjee was born in Mumbai, India in 1982. She received her B.E. degree in computer science engineering in 2006. Being brought up in a metropolitan city like Mumbai, she had increasingly become aware of environmental issues and how much of an impact environmental sciences would have in th e future. This led to her enrollment for a M.E. degree in environmental engineering sciences at the University of Florida in January 2009. Her graduate research focused on water resources with an emphasis on natural organic matter for phosphorus removal me thods in surface waters. She plans to pursue her career in this field.