<%BANNER%>

The Impact of Polycyclic Aromatic Hydrocarbons (PAHs) on Beneficial Use of Waste Materials

Permanent Link: http://ufdc.ufl.edu/UFE0042378/00001

Material Information

Title: The Impact of Polycyclic Aromatic Hydrocarbons (PAHs) on Beneficial Use of Waste Materials
Physical Description: 1 online resource (174 p.)
Language: english
Creator: AZAH,EDMUND M
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2011

Subjects

Subjects / Keywords: ACENAPHTHENE -- ACENAPHTHYLENE -- ANTHRACENE -- AROMATIC -- ASPHALT -- ASSESSMENT -- BENEFICIAL -- BIOACCESSIBILITY -- BIOAVAILABILITY -- CHRYSENE -- CLEANING -- COLUMN -- CONTAMINANTS -- DISTRIBUTION -- DITCH -- FLUORANTHENE -- FLUORENE -- FRACTIONATION -- GASTROINTESTINAL -- GWCTL -- HYDROCARBONS -- INVITRO -- LEACHING -- LYSIMETERS -- MOBILIZATION -- NAPHTHALENE -- PAH -- PAVEMENT -- PHENANTHRENE -- POLLUTANTS -- POLYCYCLIC -- PYRENE -- RAP -- RECLAIMED -- RESIDUALS -- RISK -- ROADWAY -- SCTL -- SEDIMENTS -- SHINGLES -- STORMWATER -- STREET -- SWEEPINGS -- TOXICITY -- WASTE
Environmental Engineering Sciences -- Dissertations, Academic -- UF
Genre: Environmental Engineering Sciences thesis, Ph.D.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: Wastes generated from municipal cleaning activities such as street sweeping, ditch cleaning, stormwater pond maintenance and catch basin sediment removal need to be managed appropriately. Also requiring management are reclaimed asphalt pavement (RAP) and milled asphalt shingles. The common management practices for these waste streams are direct landfilling and stockpiling for future use or disposal. Beneficial use of these types of waste is a good alterative to landfilling. However, there are genuine concerns about possible soil and groundwater contamination by pollutants such as polycyclic aromatic hydrocarbons (PAHs), which are known to occur in low concentrations in several of these waste streams. The absence of sufficient scientific data on these PAHs has limited scientists, engineers, and policy-makers when making decisions concerning reuse of these wastes. In addition, inflow of new scientific information on PAHs has lead to downward revision of regulatory thresholds for some of these organic pollutants over the years, rendering previous research work inconclusive. Regulatory threshold values for solid waste are based on risk assessments. These assessments using animals usually assume a one hundred percent bioavailability. This could lead to over-conservative limitation of beneficial use of solid waste. The purpose of this research was to investigate the impact of PAHs on beneficial use of roadway and storm system residuals and asphalt waste materials. Total and leachable concentrations of PAHs in roadway and storm system residuals were investigated using United States Environmental Protection Agency (US EPA) methods 3550 and 1312. Column leaching studies and batch leaching tests using the synthetic precipitation leaching procedure (USEPA method 1312) were conducted on reclaimed asphalt pavement (RAP) and milled shingles to determine potential leaching of PAHs from these wastes. Size fractionation was performed on the roadway and storm system residuals and the PAHs associated with each fraction determined. An in vitro study was conducted using a gastrointestinal leaching test to ascertain bioaccessibility of PAHs in these waste streams. Analyses of the samples were achieved by employing high-performance liquid chromatography (HPLC) equipped with ultraviolet (UV) and fluorescence detectors. Results in this study showed the presence of all the 16 US EPA priority PAHs in measurable quantities. The measured total and leachable PAH concentrations were lower than the regulatory Soil Cleanup Target levels (SCTLs) and Ground Water Cleanup Target Levels (GWCLs) except for benzo(a)pyrene. The mean benzo(a)pyrene concentration in the sampled street sweepings was above the residential SCTL, but lower than the industrial SCTL. PAHs were found mobilized in the lower fine and medium coarse fractions of the waste. Abraded asphalt particles from roadways were believed to be the source of PAHs in the coarse fractions. Microscopic studies of the fractionated samples revealed the presence of asphalt particles in these fractions. In vitro study results found PAH bioaccessibility to range from 1.7% to 49% in six samples studied.
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 EDMUND M AZAH.
Thesis: Thesis (Ph.D.)--University of Florida, 2011.
Local: Adviser: Townsend, Timothy G.
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 2011
System ID: UFE0042378:00001

Permanent Link: http://ufdc.ufl.edu/UFE0042378/00001

Material Information

Title: The Impact of Polycyclic Aromatic Hydrocarbons (PAHs) on Beneficial Use of Waste Materials
Physical Description: 1 online resource (174 p.)
Language: english
Creator: AZAH,EDMUND M
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2011

Subjects

Subjects / Keywords: ACENAPHTHENE -- ACENAPHTHYLENE -- ANTHRACENE -- AROMATIC -- ASPHALT -- ASSESSMENT -- BENEFICIAL -- BIOACCESSIBILITY -- BIOAVAILABILITY -- CHRYSENE -- CLEANING -- COLUMN -- CONTAMINANTS -- DISTRIBUTION -- DITCH -- FLUORANTHENE -- FLUORENE -- FRACTIONATION -- GASTROINTESTINAL -- GWCTL -- HYDROCARBONS -- INVITRO -- LEACHING -- LYSIMETERS -- MOBILIZATION -- NAPHTHALENE -- PAH -- PAVEMENT -- PHENANTHRENE -- POLLUTANTS -- POLYCYCLIC -- PYRENE -- RAP -- RECLAIMED -- RESIDUALS -- RISK -- ROADWAY -- SCTL -- SEDIMENTS -- SHINGLES -- STORMWATER -- STREET -- SWEEPINGS -- TOXICITY -- WASTE
Environmental Engineering Sciences -- Dissertations, Academic -- UF
Genre: Environmental Engineering Sciences thesis, Ph.D.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: Wastes generated from municipal cleaning activities such as street sweeping, ditch cleaning, stormwater pond maintenance and catch basin sediment removal need to be managed appropriately. Also requiring management are reclaimed asphalt pavement (RAP) and milled asphalt shingles. The common management practices for these waste streams are direct landfilling and stockpiling for future use or disposal. Beneficial use of these types of waste is a good alterative to landfilling. However, there are genuine concerns about possible soil and groundwater contamination by pollutants such as polycyclic aromatic hydrocarbons (PAHs), which are known to occur in low concentrations in several of these waste streams. The absence of sufficient scientific data on these PAHs has limited scientists, engineers, and policy-makers when making decisions concerning reuse of these wastes. In addition, inflow of new scientific information on PAHs has lead to downward revision of regulatory thresholds for some of these organic pollutants over the years, rendering previous research work inconclusive. Regulatory threshold values for solid waste are based on risk assessments. These assessments using animals usually assume a one hundred percent bioavailability. This could lead to over-conservative limitation of beneficial use of solid waste. The purpose of this research was to investigate the impact of PAHs on beneficial use of roadway and storm system residuals and asphalt waste materials. Total and leachable concentrations of PAHs in roadway and storm system residuals were investigated using United States Environmental Protection Agency (US EPA) methods 3550 and 1312. Column leaching studies and batch leaching tests using the synthetic precipitation leaching procedure (USEPA method 1312) were conducted on reclaimed asphalt pavement (RAP) and milled shingles to determine potential leaching of PAHs from these wastes. Size fractionation was performed on the roadway and storm system residuals and the PAHs associated with each fraction determined. An in vitro study was conducted using a gastrointestinal leaching test to ascertain bioaccessibility of PAHs in these waste streams. Analyses of the samples were achieved by employing high-performance liquid chromatography (HPLC) equipped with ultraviolet (UV) and fluorescence detectors. Results in this study showed the presence of all the 16 US EPA priority PAHs in measurable quantities. The measured total and leachable PAH concentrations were lower than the regulatory Soil Cleanup Target levels (SCTLs) and Ground Water Cleanup Target Levels (GWCLs) except for benzo(a)pyrene. The mean benzo(a)pyrene concentration in the sampled street sweepings was above the residential SCTL, but lower than the industrial SCTL. PAHs were found mobilized in the lower fine and medium coarse fractions of the waste. Abraded asphalt particles from roadways were believed to be the source of PAHs in the coarse fractions. Microscopic studies of the fractionated samples revealed the presence of asphalt particles in these fractions. In vitro study results found PAH bioaccessibility to range from 1.7% to 49% in six samples studied.
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 EDMUND M AZAH.
Thesis: Thesis (Ph.D.)--University of Florida, 2011.
Local: Adviser: Townsend, Timothy G.
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 2011
System ID: UFE0042378:00001


This item has the following downloads:


Full Text

PAGE 1

1 THE IMPACT OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) ON BENEFICIAL USE OF WASTE MATERIALS By EDMUND MAWULI AZAH A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2011

PAGE 2

2 2011 Edmund Mawuli Azah

PAGE 3

3 To my mother and late sister Sylvia

PAGE 4

4 ACKNOWLEDGMENTS I would like to offer humble and sincere thanks to Almighty God, to whom all g lory and praises are due. Also in pursing this degree, I received assistance and guidance from many sources, and I would like to recognize these persons for their invaluable contributions. Special thanks go to my advisor Dr Timothy Townsend for his suppo rt, advice and supervision throughout the conduct of this work. I thank my advisory committee member s for their guidance. I thank my family in Ghana whose prayers and love continue to be behind my ability to complete this work. Sincere and special thanks go to my dear wife Beatrice Azah for her prayer s and moral support. Finally, special thanks go to the graduate students and post doctorial fellows of the solid and hazardous waste research group who helped in many ways in bringing this work to fruition.

PAGE 5

5 TABLE OF CONTENTS page ACKNOWLEDGMENTS ................................ ................................ ................................ .. 4 LIST OF TABLES ................................ ................................ ................................ ............ 8 LIST OF FIGURES ................................ ................................ ................................ ........ 11 LIST OF ABBREVIATIONS ................................ ................................ ........................... 15 ABSTRACT ................................ ................................ ................................ ................... 16 CHAPTER 1 INTRODUCTION ................................ ................................ ................................ .... 19 Polycyclic Aromatic Hydrocarbons ................................ ................................ .......... 19 Sources of PAHs in Environment ................................ ................................ ..... 19 Toxici ty of PAHs ................................ ................................ ............................... 21 Regulatory Thresholds for PAH Compounds ................................ .................... 23 Analytical Measurement Techniques for PAH Compounds .............................. 23 Extraction and cleanup methods ................................ ................................ 24 Sample Analysis ................................ ................................ ........................ 25 Challenges to Beneficial us e of Roadway and Storm System Waste ............... 26 Research Objectives ................................ ................................ ............................... 28 Research Approach ................................ ................................ ................................ 30 Outline of Dissertation ................................ ................................ ............................. 32 2 ASSESSMENT OF DIRECT EXPOSURE RISK AND POTENTIAL LEACHABILITY OF POLYCYCLIC AROMATIC HYDROCARBONS FROM ROADWAY AND STORM SYSTEM RESIDUALS ................................ .................. 33 Introduction ................................ ................................ ................................ ............. 33 Sampling Location ................................ ................................ ................................ .. 36 Material and Method ................................ ................................ ............................... 37 Sample Collection ................................ ................................ ............................ 37 Total PAH Extraction and Cleanup ................................ ................................ ... 38 Leachable PAHs Determination ................................ ................................ ....... 39 Analysis of Extracts by HPLC ................................ ................................ ........... 39 Quality Control/ Quality Assurance ................................ ................................ ... 40 Statistical Analysis ................................ ................................ ............................ 41 Results and Discussions ................................ ................................ ......................... 41 Quality Control/Quality Assurance Results ................................ ....................... 42 Total Polycyclic Aromatic Hydrocarbons ................................ .......................... 42 Leaching of Polycyclic Aromatic Hydrocarbons ................................ ................ 44 Comparison of Results with Published Literature ................................ ............. 45

PAGE 6

6 Summary and Conclusion ................................ ................................ ....................... 48 3 LEACHING OF POLYCYCLIC AROMATIC HYROCARBONS FROM RECLAIMED ASPHALT PAVEMENT ( RAP ) AND MILLED SHINGLES ................. 61 Introduction ................................ ................................ ................................ ............. 61 Previous Research on RAP Leaching ................................ ................................ ..... 61 Materials and Methods ................................ ................................ ............................ 62 Column Leaching Studies ................................ ................................ ................. 62 Column design and setup ................................ ................................ .......... 63 Column leaching tests ................................ ................................ ................ 65 Leachate extraction ................................ ................................ .................... 65 Ba tch Leaching Studies ................................ ................................ .................... 66 Results and Discussions ................................ ................................ ......................... 66 Physical Characterization Results ................................ ................................ .... 66 Quality Control/Quality Assurance (QA/QC) ................................ ..................... 67 Batch Leaching Results ................................ ................................ .................... 68 Column Leaching Results ................................ ................................ ................. 68 Leaching under unsaturated condition ................................ ....................... 69 Leaching under saturated condition ................................ ........................... 71 Comparison of Results with Published Literature ................................ ............. 72 Summary and Conclusion ................................ ................................ ....................... 74 4 POLYCYCLIC AROMATIC HYDROCARBON DISTRIBUT ION IN VARIOUS SIZE FRACTIONS OF ROADWAYS AND STORM SYSTEM RESIDUALS ........... 88 Introduction ................................ ................................ ................................ ............. 88 Materials and Methods ................................ ................................ ............................ 89 Sample Collection ................................ ................................ ............................ 89 Size Separation ................................ ................................ ................................ 90 PAH Concentration Determination ................................ ................................ ... 90 Total Organic Carbon Analysis and Microscopic Studies ................................ 91 Results and Discussions ................................ ................................ ......................... 91 Quality Control/Quality Assurance (QA/QC) ................................ ..................... 91 Total Organic Content Distribution in Size Fractions ................................ ........ 91 Distributio n of PAH in size fractions ................................ ................................ 92 Comparison of Results with Published Literature ................................ ............. 93 Summary and Conclusion ................................ ................................ ....................... 96 5 BIOACCESSIBILITY OF POLYCYCLIC AROMATIC HYDROCARBONS IN ROADWAY AND STORM SYSTEM RESIDUE USING IN VITRO GASTROINTESTINAL LEACHING TEST ................................ ............................. 120 Introduc tion ................................ ................................ ................................ ........... 120 Materials and Methods ................................ ................................ .......................... 122 Sample Collection ................................ ................................ .......................... 122 In Vitr o Gastrointestinal Leaching Test ................................ ........................... 123

PAGE 7

7 Sample preparation ................................ ................................ .................. 123 Leaching solution preparation and leaching test ................................ ...... 123 PAH extraction from gastrointestinal solution ................................ ........... 124 Sample Analysis ................................ ................................ ............................. 125 Results an d Discussions ................................ ................................ ....................... 126 Quality Control/Quality Assurance (QA/QC) ................................ ................... 126 Comparison of Results with Published In Vitro and In Vivo Studie s ............... 127 Summary and Conclusion ................................ ................................ ..................... 129 6 SUMMARY, CONCLUSIONS AND RECOMMENDATION FOR FUTURE WORK ................................ ................................ ................................ ................... 133 Summary of Major Observations ................................ ................................ .......... 133 Interpretation and Implication ................................ ................................ ................ 134 Recommendations for Future W ork ................................ ................................ ...... 136 APPENDIX A SUPPLEMENTARY TABLES ................................ ................................ ............... 137 B SUPPLEMENTARY FIGURES ................................ ................................ ............. 153 LIST OF REFERENCES ................................ ................................ ............................. 169 BIOGRAPHICAL SKETCH ................................ ................................ .......................... 174

PAGE 8

8 LIST OF TABLES Table page 1 1 pollutant PAHs and selected physical chemical properties ................................ ................................ ................................ ........... 20 1 2 ................ 24 1 3 Regulatory threshold for PAH compounds in Florida (FDEP, 2005). .................. 24 2 1 Sampling locations of sites investigated ................................ ............................. 37 2 2 Results of spike recovery, relative percentage difference (RPD), and method detection limit (MDL) using UV detector. ................................ ............................ 50 2 3 Results of spike recovery and method detection l imit using Fluorescence detector. ................................ ................................ ................................ ............. 50 2 4 Mean total concentrations of ditch cleaning samples using UV detector (mg/Kg) ................................ ................................ ................................ ............... 51 2 5 Me an total concentrations of stormwater pond samples using UV detector (mg/Kg) ................................ ................................ ................................ ............... 52 2 6 Mean total concentrations of street sweeping samples using UV detector (mg/Kg) ................................ ................................ ................................ ............... 53 2 7 Mean total concentrations of catch basin samples using UV detector (mg/Kg) .. 54 2 8 Mean leached concentrations of ditch cleaning samples using fluoresc ence detector (ng/L) ................................ ................................ ................................ .... 55 2 9 Mean leached concentrations of stormwater pond samples using fluorescence detector (ng/L) ................................ ................................ ............... 56 2 10 Me an leached concentrations of street sweeping samples using fluorescence detector (ng/L) ................................ ................................ ................................ .... 57 2 11 Mean leached concentrations of catch basin samples using fluorescence (ng/L) ................................ ................................ ................................ .................. 58 2 12 Reported polycyclic aromatic hydrocarbons in literature ................................ .... 59 2 13 PAH concentrations in street sweepings, stormwater pond sediment, and catch basin sediments reported by Townsend (2002) ................................ ........ 60 3 1 Physical characteristics results ................................ ................................ ........... 67

PAGE 9

9 3 2 Accuracy and precision of leached PA Hs analysis in column studies using spiked samples ................................ ................................ ................................ .. 76 3 3 Results of SPLP batch leaching test conducted of roadway and storm system samples (ng/L) ................................ ................................ ................................ .... 77 3 4 Comparison of this study to column study results in literature ............................ 79 3 5 Comparison of this study to batch study results in literature ............................... 80 4 1 PAHs distribution in sediments reported in literature ................................ .......... 97 5 2 Results of in vitro studies conducted of roadways and storm system samples 131 5 3 PAH mobilization from polluted soil, sewage sludge, shredded metal scrap, blast sand and street asphalt by means of gastro intestinal model .................. 132 5 4 Percent of phenanthrene mobilized from soils using in vitro extraction ............ 132 5 5 Bioavailability of soil sorbed phenanthrene in rats treated with 400 g/Kg bw .. 132 5 6 Properties of soils with benzo(a)pyrene relative bioavailability data from mice 132 A 1 Accuracy of total PAHs analysis using spiked samples ................................ .... 137 A 2 Accuracy and precision of batch leached PAHs analysis using spiked street sweping samples ................................ ................................ .............................. 137 A 3 Accuracy of total PAHs anal ysis in fractionation studies using spiked fractionated samples ................................ ................................ ........................ 138 A 4 Precision in fractionation study analysis using fractionated dich cleaning sample (212 425 m) ................................ ................................ ........................ 138 A 5 Precision in fractionation study analysis using fractionated stormwater pond samples (212 425 m) ................................ ................................ ....................... 139 A 6 Accuracy of PAHs analysis in in vitro stu dies using spiked samples ................ 139 A 7 Precision in in vitro study analysis using duplicate stormwater pond samples 140 A 8 Precision in in vitro study analysis using duplicate dich cleaning samples ....... 140 A 9 Concentrations of PAHs in leachate from column containing BRN (ng/L) ........ 141 A 10 Concentrations of PAHs in leachate from column containing BRN duplicate (ng/L) ................................ ................................ ................................ ................ 142 A 11 Concentrations of PAHs in leachate from column containing LC (ng/L) ........... 143

PAGE 10

10 A 12 Concentrations of PAHs in leachate from column containing JAX (ng/L) ......... 144 A 13 Concentrations of PAHs in leachate from column contai ning GNV (ng/L) ........ 145 A 14 Concentrations of PAHs in leachate from column containing PEM (ng/L) ........ 146 A 15 Concentrations of PAHs in leachate from column containing MAR (ng/L) ........ 147 A 16 Concentrations of PAHs in leachate from column without a sample (ng/L) ...... 148 A 17 Concentrations of PAHs in leachate from column containing BRN under saturated condition (ng/L) ................................ ................................ ................. 149 A 18 Concentrations of PAHs in leachate from column containing JAX under saturated condi tion (ng/L) ................................ ................................ ................. 149 A 19 Concentrations of PAHs in leachate from column containing PEM under saturated condition (ng/L) ................................ ................................ ................. 150 A 20 Con centrations of PAHs in leachate from column containing MAR under saturated condition (ng/L) ................................ ................................ ................. 150 A 21 Concentrations of PAHs in leachate from column containing LC under saturated condition (ng/ L) ................................ ................................ ................. 151 A 22 Concentrations of PAHs in leachate from column containing GNV and GNV duplicate under saturated condition (ng/L) ................................ ....................... 151 A 23 Fractionation results of ditch cleaning sediment in mg/Kg ................................ 152 A 24 Fractionation results of catch basin sediment in mg/Kg ................................ .... 152

PAGE 11

11 LIST OF FIGURES Figure p age 1 1 Molecular structure and molecular weight of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) (Henner Pascale, et al., 1997). ......................... 21 1 2 Reaction steps of Benzo(a)pyrene in the mammalian cell resulting in cancer (Morrison and Boyd, 1987). ................................ ................................ ................ 22 2 1 Study sites located in Florida ................................ ................................ .............. 36 3 1 Study sites where RAP and shingles were sampled ................................ ........... 63 3 2 Column leaching apparatus. ................................ ................................ ............... 64 3 3 Grain size distribution of milled shingles and RAP samples ............................... 78 3 4 Leached PAH concentration versus L/S ratio under unsaturated condition. A) fluoranthene B) pyrene ................................ ................................ ....................... 81 3 5 Leached PAH concentration versus L/S ratio under unsaturated condition. A) benzo(k)fluoranthene B) benzo(a)pyrene ................................ ........................... 82 3 6 Leached PAH conce ntration from RAP and shingles versus L/S ratio under unsaturated condition. A) benzo(ghi)perylene from shingles B) fluoranthene from RAP samples ................................ ................................ .............................. 83 3 7 Leached PAH concentration from RAP samp les versus L/S ratio under unsaturated condition. A) pyrene B) benzo(k)fluoranthene ................................ 84 3 8 Leached PAH concentration versus L/S ratio under unsaturated condition. A) benzo(b)fluoranthene B) be nzo(a)pyrene ................................ ........................... 85 3 9 Leached PAHs from milled shingles (BRN) under saturated condition. A) fluoranthene, pyrene, benzo(b)fluoranthene, and benzo(a)anthracene B) benzo(k)fluoranthene, benzo(ghi) perylene, benzo(a)pyrene, and dibenzo(ah)anrhracene ................................ ................................ ...................... 86 3 10 Leached PAHs from RAP samples under saturated condition. A) RAP sample PEM B) RAP sample JAX ................................ ................................ ...... 87 4 1 Distribution of summed PAH in size fractions. A) distribution in sample SWP 5 B) distribution in sample SWP 1 ................................ ................................ ...... 97 4 2 Distribution of summed PAH in size fraction s. A) distribution in sample SS 1 B) distribution in sample SS 7 ................................ ................................ ............ 98

PAGE 12

12 4 3 Distribution of summed PAH in size fractions. A) distribution in sample CB 6 B) distribution in sample CB 11 ................................ ................................ .......... 99 4 4 Distribution of summed PAH in size fractions. A) distribution in sample DCL 7 B) distribution in sample DCL 8 ................................ ................................ ........ 100 4 5 Total organic carbon content of A) ditch cleaning samples and B) stormwater pond samples ................................ ................................ ................................ ... 101 4 6 Total organic carbon content of A) street sweeping samples and B) catch basin samples ................................ ................................ ................................ ... 102 4 7 Comparison of carbon normalized PAH distribution with non normalized distribution. A) SWP 5 normalized B) SWP 5 unnormalized C) SWP 1 normalized D) SWP 1 unnormalized E) DCL 7 normalized F) DCL 7 unnormaliz ed ................................ ................................ ................................ .... 103 4 8 PAH concentrations in ditch cleaning fractions. A) Anthracene in DCL 8 B) Pyrene in DCL 8 ................................ ................................ ............................... 104 4 9 PAH concentrations in stornwater pond fractions. A) Naphthalene in SWP 5 B) Benzo(a)pyrene in SWP 5 ................................ ................................ ........... 105 4 10 PAH concentrations in stormwater pond fractions. A) Phenanthrene in SWP 5 B) chrysene in SWP 1 ................................ ................................ ................... 106 4 11 PAH concentrations in street sweeping fractions. A) Benzo(k)fluoranthene in SS 1 B) Naphthalene in SS 7 ................................ ................................ ........... 107 4 12 PAH concentra tions in street sweeping. A) Phenanthrene in SS 7 B) Benzo(a)pyrene in SS 7 ................................ ................................ ................... 108 4 13 PAH concentrations in catch basin fractions. A) Phenanthrene in CB 6 B) Pyrene in CB 6 ................................ ................................ ................................ 109 4 14 PAH concentrations in catch basin fractions. A) Benzo(k)fluoranthene in CB 6 B) Anthracene in CB 11 ................................ ................................ ................ 110 4 15 PAH concentrations in catch b asin fractions. A) Fluoranthene in CB 11 B) Benzo(a)pyrene in CB 11 ................................ ................................ ................. 111 4 16 Relative enrichment of individual PAHs stormwater pond sediment fractions. A) sample SWP 1 B) sample SWP 5 ................................ ................................ 112 4 17 Relative enrichment of individual PAHs ditch cleaning sediment fractions. A) sample DCL 7 B) sample DCL 8 ................................ ................................ ...... 113

PAGE 13

13 4 18 Relative enr ichment of individual PAHs catch basin sediment fractions. A) sample CB 6 B) sample CB 11 ................................ ................................ ......... 114 4 19 Relative enrichment of individual PAHs in street sweeping fractions. A) sample SS 1 B) sample SS 7 ................................ ................................ ........... 115 4 20 Correlation between total PAH (mg/Kg) and total organic carbon (%) in various samples. A) sample CB 6 B) sample SS 7 ................................ .......... 116 4 21 Correlation between total PAH (mg/Kg) and total organic carbon (%) in various samples. A) sample DCL 8 B) sample CB 11 ................................ ...... 117 4 22 Correlation between total PAH (mg/Kg) and total org anic carbon (%) in various samples. A) sample DCL 7 B) sample SWP 5 ................................ ..... 118 4 23 Correlation between total PAH (mg/Kg) and total organic carbon (%) in various samples. A) sample SWP 1 B) sample SS 1 ................................ ....... 119 5 1 Mobilization of PAHs in the in vitro extraction fluid of various samples ............ 131 B 1 Picture of ditch cleaning ................................ ................................ ................... 153 B 2 Picture of ditch cleaning ................................ ................................ ................... 153 B 3 Distribution of PAHs in catch basin samples. A) distribution of naphthalene B) distribution of a cenaphthene ................................ ................................ ............ 154 B 4 Distribution of PAHs in catch basin samples. A) distribution of phenanthrene B) distribution of anthracene ................................ ................................ ............. 155 B 5 Distribution of PAHs in catch basin samples. A) distribution of fluoranthene B) distribution of pyrene ................................ ................................ .................... 156 B 6 Distribution of PAHs in catch basin samples. A) distribution of benzo(k)fl uoranthene B) distribution of chrysene ................................ ............. 157 B 7 Distribution of PAHs in catch basin samples. A) distribution of benzo(g,h,i)perylene B) distribution of benzo(a)pyrene ................................ .... 158 B 8 Distribution of PAHs in leached catch basin samples A) distribution of acenaphthene B) distribution of phenanthrene ................................ ................. 159 B 9 Distribution of PAHs i n leached catch basin samples A) distribution of anthracene B) distribution of fluoranthene ................................ ........................ 160 B 10 Distribution of PAHs in leached catch basin samples A) distribution of benzo (k) Fluoranthe ne B) distribution of pyrene ................................ ........................ 161

PAGE 14

14 B 11 Distribution of PAHs in leached catch basin samples A) distribution of benzo (g,h,i)perylene B) distribution of benzo(a)pyrene ................................ .............. 162 B 12 Distribution of PAHs in leached catch basin samples A) distribution of naphthalene B) distribution of acenaphthene ................................ ................... 163 B 13 Distribution of PAHs i n leached catch basin samples A) distribution of phenanthrene B) distribution of anthracene ................................ ...................... 164 B 14 Distribution of PAHs in leached catch basin samples A) distribution of fluoranthene B) dist ribution of pyrene ................................ ............................... 165 B 15 Distribution of PAHs in leached catch basin samples A) distribution of benzo (k) Fluoranthene B) distribution of chrysene ................................ ..................... 166 B 16 Distribution of PAHs in leached catch basin samples A) distribution of benzo(g,h,i)perylene B) distribution of benzo(a)pyrene ................................ .... 167 B 17 Distribution of PAHs in le ached catch basin samples A) distribution of benzo(a)anthracene B) distribution of benzo(b)fluoranthene ............................ 168

PAGE 15

15 LIST OF ABBREVIATION S PAH Polycyclic aromatic hydrocarbons RAP Reclaimed asphalt pavement SPLP Synthetic precipita tion leaching procedure SCTL Soil cleanup target level GPC Gel permeation chromatography MDL Method detection limit GWCTL Groundwater cleanup target level TOC Total organic carbon Sum of 16 priority polycyclic aromatic hydrocarbons RPD Relative percentage diffrence C & D Construction and demolition

PAGE 16

16 Abstract of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy THE IMPACT OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) ON BENEFICIAL USE OF WASTE MATERIALS By Edmund Mawuli Azah May 2011 Chair: Timothy G. Townsend Major: Environmental Engineering Sciences Wast e s generated from municipal cleaning activities such as street sweeping, ditch cleaning, stormwater pond maintenance and catch basin sediment removal need to be managed appropriately Also requiring management are reclaimed asphalt pavement (RAP) and mille d asphalt shingles The common management practices for these waste streams are direct landfilling and stockpiling for future use or disposal. Beneficial use of these types of waste is a good alterative to landfilling. However, there are genuine concerns a bout possible soil and groundwater contamination by pollutants such as polycyclic aromatic hydrocarbons (PAHs) which are known to occur in low concentrations in several of these waste streams. The absence of sufficient scientific data on these PAHs ha s li mited scientist s engineers, and policy makers when making decision s concerning reuse of these wastes. In addition, inflow of new scientific information on PAHs has lead to downward revision of regulatory threshold s for some of these organic pollutants ove r the years, rendering previous research work inconclusive. Regulatory threshold values for solid waste are based on risk assessments. These assessment s using animals usually assume a one hundred percent bioavailability. This could lead to over conservativ e limitation of beneficial use of solid waste

PAGE 17

17 The purpose of this research was to investigate the impact of PAHs on beneficial use of r oadway and storm system residuals and asphalt waste materials Total and leachable concentrations of PAHs in roadway a nd storm system residuals were investigated using United States Environmental P rotection A gency ( US EPA ) methods 3550 and 1312. Column leaching studies and batch leaching test s using the synthetic precipitation leaching procedure (USEPA method 1312) were c onducted on reclaimed asphalt pavement (RAP) and milled shingles to determine potential leaching of PAHs from these wastes. Size fractionation was performed on the roadway and storm system residuals and the PAHs associated with each fraction determined. An i n vitro study was conducted using a gastrointestinal leaching test to ascertain bioaccessibility of PAHs in the se waste streams. Analyses of the samples were achieved by employing h igh performance liquid chromatography ( HPLC ) equipped with ultraviolet ( U V ) and f luorescence detectors. Results in this study showed the presence of all the 16 US EPA priority PAHs in measurable quantities. The measured total and leachable PAH concentrations were lower than the regulatory Soil Cleanup Target levels (SCTLs) and Ground Water Cleanup Target Levels (GWCLs) except for benzo(a)pyrene The m ean b enzo(a)pyrene concentration in the sampled street sweeping s was above the residential SCTL but lower than the industrial SCTL PAHs were found mobilized in the lower fine and medi um coarse fractions of the waste. Abraded asphalt particles from roadways were believed to be the source of PAHs in the coarse fractions. Microscopic studies of the fractionated samples revealed the presence of asphalt particles in these fractions. In

PAGE 18

18 vitro study results found PAH bioaccessibility to rang e from 1.7% to 49 % in six samples studied.

PAGE 19

19 CHAPTER 1 INTRODUCTION Polycyclic Aromatic Hydrocarbons Polycyclic aromatic hydrocarbons (PAHs) are organic chemicals composed of fused benzene rings. They a re ubiquitous environmental contaminants that consist of more than 100 chemicals (Ramesh et al., 2004) The United States Environmental Protection Agency has listed 16 of these compounds on its list of of priority pollutants which are regulated. PAHs are hydrophobic compounds and their persistence within the ecosystem is due chiefly to their low water solubility (Cerniglia, 1992) Solubility and volatility of PAHs decrease with increasing molecular weight (Table 1 1 ). Polycyclic aromatic hydrocarbons from environmental sources rapidly become associated with sediments where they may become buried and persist until degraded, resuspended, bioaccumulated, or removed e .g. by dredging or desilting roadside ditch cleaning The environmental persistence and lipop hilicity increases as molecular size of PAH increases. As the number of fused benzene rings increases, the toxicological concern shifts towards carcinogenesis The possible fate of PAHs in the environment include volatilization, photooxidation, chemical ox idation, bioaccumulation, adsorption to soil particle, leaching and microbial degradation (Cerniglia, 1992) Figure 1 shows the 16 PAH compounds which have been listed as priority pollutants by US EPA (Henner et al., 1997) Sources of PAHs in Environment Polycyclic aromatic hydrocarbon (PAHs) sources are both natural and anthropogenic. Natural sources include volcanic activity and forest fires, while a nthropogenic sources include combustion of fossil fuel in heat and power generation

PAGE 20

20 Table 1 1 16 priority pollutant PAHs and selected physical chemical properties (Bojes and Pope, 2007) Chemicals Structure (# of rings ) Molecular Weight (g/mole) Solubility in H 2 O (mg/L Vapor pressure (mm Hg) Naphthalene Acenaphthene Acenaphthylene Anthracene Phenanthrene Fluorene Fluoranthene Benz(a)anthracene Chrysene Pyrene Benzo(a)pyrene Benzo(b)fluoranthene Benzo(k)fluoranthene Dibenz(a,h)anthracene Benzo(g,h,i)perylene Indeno(1,2,3, c,d)pyrene 2 3 3 3 3 3 4 4 4 4 5 5 5 6 6 6 128.2 154.2 152.2 178.2 178.2 166.2 202.3 228.3 228.3 202.3 252.3 252.3 252.3 278.4 276.3 276.3 3 1 E+1 3.8 E+0 1 6 E+1 4.5E 2 1.1 E+0 1.9 E+0 2.6E 1 1.1E 2 1.5E 3 1.3E 1 3.8E 3 1.5E 3 8.0E 4 5.0E 4 2.6E 4 6.2E 2 8.89E 2 3.75E 3 2.90E 2 2.55E 5 6.80E 4 3.24E 3 8.13E 6 1.54E 7 7.80E 9 4.25E 6 4.89E 9 8.06E 8 9.59E 11 2.10E 11 1.00E 10 1.40E 10 (Juhasz and Naidu, 2000) Rapid industrialization in the past century was powered by fossil fuel. Fossil fuel still remains the primary source of energy on the globe. Some of the leading uses of fossi l fuel are electric ity generation and transportation However, PAHs are products of incomplete combustion of fossil fuel. Internal combustion engines generate large amount of PAHs which adds to the environmental pool. In the United States, vehicle emission is a major contributor to urban environmental contamination, particularly in areas adjacent to highways and airports (Harvey, 1997) Coal tars, asphalt and petroleum residue all contain PAHs representing a wide range of molecular sizes and structural typ es. Similarly, n atural sources such as forest fires and volcanic activities contribute substantially to the amount of PAHs in the environment. PAH s ha ve been detected in a wide range of environmental samples, including soil (Jones et al., 1989) sediments

PAGE 21

21 Figure 1 1 Molecular structure and molecular weight of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) (Henner Pascale, et al., 1997) (Youngblood and Blumer, 1975; Laflamme and Hites, 1978; Shiaris and Jambard Sweet, 1986), sludge (Olesz czuk and Baran, 2004), water (Cerniglia and Heitkamp, 1989), air (Freeman and Cattell, 1990), oils, tars (Nishioka, et al., 2002), and food stuff (Dipple, et al., 1991; Lijinsky, 1991). Toxicity of PAHs A number of PAHs have been shown to be acutely toxic. However, the major concern about PAHs is their metabolic transformation into mutagenic, carcinogenic, and teratogenic agents such as dihydrodiol epoxide. These metabolites bind to and disrupt

PAGE 22

22 DNA and RNA, which is the basis for tumor formation (Wild and J ones, 1995) Organisms ensure that foreign substances that enter them are eliminated. Low water soluble intruders are eliminated by first converting them into more water soluble forms which are readily excreted. In order to eliminate a PAH which has low wa ter solubility from an organism, compounds are first converted into epoxides, followed by hydrolysis and then further epoxidation to produce dihydroxly epoxide. This process is catalyzed by the enzyme dioxygenase. These dihydroxyl epoxides are believed to be the actual carcinogens form ed by metabolism of PAHs. The dihydroxyl epoxides form adducts with DNA and RNA in human cells. The attachment of this large hydrocarbon group to DNA distorts the double helix strands. This damage leads to mutations and with mutations, an increased likelihood of carcinogenesis (Morrison and Boyd, 1987) The toxic effect of most concern from exposure to PAHs is cancer. However, PAHs exposure in animals have been observed to be associated with other effects including reproductiv e toxicity Figure 1 2 Reaction steps of Benzo(a)pyrene in the mammalian cell resulting in cancer (Morrison and Boyd, 1987)

PAGE 23

23 (Mackenzie and Angevine, 1981), cardiovascular toxicity (Penn, et al., 1981; Paigen, et al., 1985), bone marrow toxicit y (Legraverend, et al., 1983), and immune system suppression (Hardin, et al., 1992). Regulatory T hresholds for PAH C ompounds Toxicity classification for PAHs has changed over the years as more scientific data ion grouped PAH s into two categories. The two groups being those capable of causing cancer (Group 2B) and those classified as non carcinogenic (Group D) (Table 1 2). This approach is the basis for risk assessment to separate PAHs into two subclasses The a pproach involved applying a cancer slope factor derived from assays on benzo(a)pyrene to the subclass of carcinogenic PAHs (Nisbet and LaGoy, 1992) For example, phenanthrene which was determined not to be carcinogenic in the past, ha s been shown to have s ome degree of limited carcinogenic activity (USEPA, 1991) The inflow of new scientific information has lead to review of regulatory threshold for PAHs over the years. In Florida for example, Groundwater Cleanup Target Levels (GWCTLs) values have been revi sed downwards for some PAHs compounds. Benzo(a)pyrene for example was lowered from 4g/L to present value of 0.05g/L while the standard for dibenz o (a,h)anthracene has been lowered from 7.5g/L to 0.005g/L (Table 1 3 ). Analytical Measurement Techniques for PAH Compounds Analytical techniques for the determination o f PAHs consist of several steps including extraction, cleanup, separation, and identification. Separation and identification is accomplished using an analytical instrument such as g as chromat ography (GC) with a mass spectrometer (MS) or flame ionization detector (FID). High performance liquid chromatography (HPLC) equipped with either ultraviolet (UV)

PAGE 24

24 adsorption or fluorescence detector is another useful instrument used widely for separation, identification and quantification of PAHs. Extraction and cleanup m ethods Nearly all extraction methods for PAHs are based on the release of compounds due to interaction with a selected solvent. Methods commonly used to accomplish this include s oxhlet ext raction, u ltrasonic extraction, m icrowave assisted extraction (MAE), Table 1 2 U nited S tates E nvironmental P rotection A rouping of PAHS (Collins et al., 1998) Group B2 Group D Benz(a)anthracene Benzo(a)pyrene Benzo(b)fluoranthene Benzo(k)flu oranthene Chrysene Dibenz(a,h)anthracene Indeno(1,2,3 cd)pyrene Acenaphthylene Anthracene Benzo(g,h,i)perylene Fluorene Fluoranthene Phenenthrene Pyrene Table 1 3 Regulatory threshold for PAH compounds in Florida (FDEP, 2005) Chemicals SCTL Residenti al mg/kg SCTL Industrial mg/kg GWCTLs g/L Dibenz(a,h)anthracene Benzo(a)pyrene Benz(a)anthracene Benzo(b)fluoranthene Benzo(k)fluoranthene Indeno(1,2,3, c,d)pyrene Anthracene Benzo(g,h,i)perylene Chrysene Acenaphthene Acenaphthylene Fluoranthene Fluoren e Phenanthrene Pyrene Naphthalene 0.1 21 000 2 500 2 400 1 800 3 200 2 600 2 200 2 400 55 0.7 300 000 52 000 20 000 20 000 59 000 33 000 36 000 45 000 300 0.005 0.2 0.05 0.05 0.5 0.05 2100 210 4.8 20 210 280 280 210 210 14

PAGE 25

25 a cceler ated solvent extraction (ASE), and s olid phase extraction (SPE). The crude extract unavoidably contains a large amount of substances other than PAHs which could interfere with analytical determination Cleanup procedures include column chromatography using various column materials. Column packing materials include alumina and silica gel. This procedure can be tedious, time consuming, and requires large volume of solvent. Moreover, t he method does not always give reproducible results. Numerous researchers ha ve successfully used SPE cartridge instead of the packed silica columns in the purification step (Marble and Delfino, 1988; Barranco, et al., 2003; Oleszczuk and Baran, 2004) Sample A nalysis Liquid and g as chromatographic techniques have been employed in analytical determination of PAHs in environmental samples after extraction and cleaning up stages ( Jang and Townsend, 2001; Barranco, et al., 2003; Poster et al., 2006) Gas liquid chromatography is based upon the partition of the analyte between a gaseo us mobile and liquid phase immobilized on the surface of an inert solid. Gas chromatography ( GC ) is normally used in conju n ction with flame ionization detect ors (FID) t hermal conductivity detectors (TCD), e lectron capture det e ctors (ECD) and m ass spectro meters (MS). Liquid chromat ographic technique exploits the partition of solute as a result of interaction between mobile liquid phase with solid phase which in cludes organic species bonded to a solid surface The use of a single solvent of constant compos ition for sepa ration in liquid chromatography is termed isocratic elution. Separation efficiency can be enhanced by gradient elution. For gradient elution two or more solvent systems that differ significantly in polarity are employed by varying solvent ra tio

PAGE 26

26 Chromatography can be classified as normal phase or reverse phase based on whether the stationary phase is polar or nonpolar. In normal phase, the stationary phase is polar while the solvent is nonpolar. The least polar component is eluted first using this system. This is because it is the most soluble in the mobile phase hence lowest retention time. In a reverse phase however, the stationary phase is nonpolar, often a hydrocarbon, while the solvent is relatively polar. The most polar component elutes first and increasing the mobile phase polarity increases the elution time (Skoog, et al., 1998) For the separation of PAHs, chemically bonded octadecysilane (C18) stationary phase column is one of the most popular columns (Poster, et al., 2006) Reverse phase HPLC on C18 column is popular because of the selectivity of this technique for separation of PAH isomers. Detection of separated PAHs is accomplished by the use of ultraviolet (UV) adsorption and fluorescence detectors. Fluorescence detectors are p articularly noted for their very low detection level (Poster, et al., 2006) Challenges to Beneficial use of Roadway and S torm S ystem W aste Large volume of waste generated from municipal cleaning activities such as street sweeping, ditch cleaning, and sedi ment removal from catch basin and storm water ponds needs to be managed. Other waste streams which require management include asphalt waste material and reclaimed screened material generated from construction and demolition (C & D) waste management. The tw o most common management practices for these wastes are direct landfilling and stockpiling for future use or disposal (Brantley and Townsend, 1999) Beneficial use of various types of waste is a good alterative to landfilling However, there are genuine co ncerns about possible soil and groundwater contamination by pollutants as a result of beneficial use of these wastes Polycyclic aromatic hydrocarbons (PAHs) are known to occur in several waste streams

PAGE 27

27 at low concentrations. Regulatory risk thresholds for some of the 16 PAH priority pollutants are very low due to their toxicity. The absence of sufficient scientific data on these PAHs has prevented scientist, engineers, and policy makers from making sound decision concerning reuse of waste. Inflow of new sci entific information on PAHs has lead to downward re vision of regulatory threshold for some of these organic pollutants over the years. Some of these new thresholds are lower than method detection limits used in previous studies (Townsend, 2002; FDEP, 2004) Another challenge is the low regulatory value for these waste streams. Regulatory threshold values for solid waste are based on risk assessments. These assessments rely on the estimated oral toxicity of the waste. These assessment s usually assume one h undred percent bioavailability. The impact of a pollutant in wastes may be over estimated because of this one hundred percent bioavailability assumption. This could lead to an over conservative limitation of beneficial use of waste. In vitro studies provid e a rapid and inexpensive method of assessing the actual fraction of pollutants in waste which is bioavailable when ingested. The fraction of PAHs available in the intestine needs to be ascertained to account for over estimation of toxicity. Polycyclic ar omatic hydrocarbons in sediments are partitioned between different phases. Investigations to determine the fraction where PAH is associated has turned out varying results. While Wang reported that PAHs are associated with large fractions (Wang et al., 200 1) ; Maruya observed the association of PAHs with fine fractions (Maruya et al., 1996) Simpson on the other hand did not observe any difference between PAH concentrations and size fractions (Simpson et al., 1998) The varying result may be due to the var ying sources of PAHs in the environment. It will be useful to

PAGE 28

28 know what compartment of the waste is associated with PAH accumulation The question of whether PAHs are present in waste as part of asphalt particles or present as leached PAHs adsorbed to orga nic coated particles needs to be addressed. This is because different size particle s in sediments show different bioavailability. Finally, experimental results showed the absence of PAH s in batch and column studies of some waste streams such as asphalt ro ad waste, street sweepings, stormwater sediments and catch basin sediment, few concerns have been raised about the past data because regulatory thresholds have been lowered since then (Townsend, 2002; FDEP, 2004) To account for changes made to regulatory standards, further studies on these waste needs to be conducted using lower detection limits. Research Objectives The purpose of this research was to investigate the impact of PAHs on beneficial use of waste materials. The t otal and leachable concentrati ons of PAHs in roadway and storm system residuals were investigated The potential leaching of PAHs from asphalt waste materials were studied using batch experiments and column leaching studies Research was conducted to identify the compactment of roadway and storm system associated with PAH accumulation. Finally, the b ioavailabilit y of PAHs found in roadway and storm system residuals w as investigated To understand the true impact of PAH contamination on waste reuse, four primary objectives were establish ed in this research. The first objective was to investigate whether both total and leachable concentrations of 16 US EPA priority PAHs found in selected waste materials, were above regulatory thresholds for soil and groundwater contamination The wastes considered for this investigation were: street sweepings, catch basin sediment s

PAGE 29

29 s tormwater pond sediments, and ditch cleanings Since PAHs maybe present at low concentrations in these waste s t reams, it was expected that leachable PAH concentrations from t hese waste s would not exceed regulatory groundwater cleanup target levels. I f total PAHs concentrations are confirmed to be lower tha n regulatory soil cleanup target levels, the case for beneficial use of these wastes would be strengthened. The second obj ective was to study leaching characteristics of PAH s from reclaimed asphalt pavement and milled asphalt shingles. The method s employed involve d both batch and column leaching studies. For the colum n study, leaching under saturated and unsaturated condition s was explored. Results are compared to Florida groundwater cleanup target levels (GWCTLs) Though asphalt waste is known to contain high concentrations of PAHs, the amount leaching out of the waste is e xpected to be lower than GWCTLs due to the hydropho bic nature of asphaltic materials. The third objective was to ascertain which compartment of roadway and storm system associated with PAH accumulation. Size fractionation followed by total PAH and total organic carbon measurement s were performed. Also, microscopic inspections of the various size fractions were conducted to identify asphalt particles. Organic carbon tends to accumulate in lower size fractions of sediments (Wang, et al., 2001) If PAHs are discovered bound to organic matter in fine fracti ons, the potential for PAH leaching into groundwater may be possible. On the other hand, if PAHs are found concentrated in coarse fractions which contain abraded asphalt particle s potential risk for leaching might be low. Accumulation of PAHs in coarse fr actions might stre ng then case for beneficial use of these wastes.

PAGE 30

30 The fourth and final objective was to determine the bioa ccesssibility of PAHs in street sweepings, catch basin sediment, stormwater sediments, and ditch cleanings using in vitro gastrointes tinal leaching tests. If PAHs are components of aspalt particles which are present coarse fractions of these wastes, bioaccessiblilty should be low. This is because ingested asphalt particle s are unlikely to dissolve completely ; hence bioaccessibility sho uld be lower tha n the one hundred percent assumed in the development of soil cleanup target levels. Research Approach Objective 1. Measure total and leachable PAH s concentration s in street sweepings, stormwater sediments, catch b asin sediments, and dit ch cleanings and compare results to risk based concentrations in beneficial use. Approach. Representative s amples consisting of 10 samples each of street sweeping s stormwater pond sediment s catch basin sediment s and ditch cleanings were collected across Florida. Total and leachable concentrations of the sampled waste were determined To determine total concentration s samples were extracted with methylene chloride using an ultrasonic extractor, cleaned with C18 octadecyl cartridge and analyzed using HPL C equipped with UV and fluorescence detectors. Batch studies were performed using the synthetic precipitation leaching procedure ( SPLP ) (US EPA method 1312) with the leachate extracted using methylene chloride The crude extract s were cleaned with C18 octa decyl cartridge and analyzed for PAHs using HPLC equipped with fluorescence detector Results were compared to Florida soil cleanup target levels (SCTLs) and groundwater cleanup target levels (GWCTLs). Objective 2 Investigate leaching of PAH compounds fro m asphalt waste by conducting batch and column studies.

PAGE 31

31 Approach. Reclaimed asphalt pavement (RAP) and milled asphalt shingles were loaded into stainless steel lysimeters. Saturated and unsaturated rain conditions were simulated in the lysimeter using SP LP leaching solution. Leachate generated as a result of passing SPLP solution th r ough the lysimeters w as collected and analysed for PAH compounds The changes in PAH concentration s with liquid to solid ratio w as monitored. For batch studies, the SPLP (US E PA method 1312) was conducted on the samples. Results from both batch and column studies were compared to Florida groundwater cleanup target levels (GWCTLs) Objective 3 Investigate sources of PAH chemicals in roadway and storm system residuals. Approa ch. Size fractionation was performed on samples of street sweepings, catch basin sediment s stormwater pond sediments, and ditch cleanings. Five size fractions (<75, 75 1 50 1 50 212 212 425 > 425 ) were generated by wet sieving the samples through a series of sieves (US Standard Sieve Series, American Scientific Products) PAH concentrations in the various fractions were measured. Also, total organic content of the various fractions were measured and results compared to PAH concentration. Objective 4 Determine the bioa ccessibility of PAH compounds in roadway and stormwater system residuals using in vitro gastrointestinal leaching test. Approach. In this experiment, street sweepings, stormwater po nd sediments, catch basin sediment s and ditch cleaning s were leached with gastric leaching solution for 1 hour at a pH of 1.5 and then 4 hours with intestinal leaching solution at a pH of 7.2 The leachate was extracted with hexane/acetone (3:1) cleaned using gel permeation

PAGE 32

32 column ( GPC ) and C18 octadecyl cartridge and analyzed for PAHs using HPLC equipped with a fluorescence detector (Hack and Selenka, 1996) Outline of Dissertation This dissertation is organized into six chapters Chapter 1 includes the introduction, research objectives, and approaches of the research. Chapters 2 through 5 provide the research methodologies, results and discussion of each individual research topic. Chapter 2 presents the assessment of direct exposure risks and potential leachability of PAHs from roadway and storm system residuals. Chapter 3 reports a study on leaching of PAHs from reclaimed asphalt pavement (RAP) and milled asphalt shingles. Chapter 4 presents a study on distribution of PAHs in various size fractions of r oadway and storm system residuals. Chapter 5 examines bioaccessibility of PAHs in roadway and storm system residuals using in vitro gastrointestinal leaching test. Chapter 6 provides the comprehensive conclusion of entire research for this dissertation an d suggestions for future research Appendi ces A and B contain additional information for chapters 2 through 6. The references cited and a bibliographic sketch are included at the end of the dissertation.

PAGE 33

33 CHAPTER 2 ASSESSMENT OF DIRECT EXPOSURE RISK AND POTENTIAL LEACHABILI TY OF POLYCYCLIC AROMATIC HYDROCARBONS FROM RO ADWAY AND STORM SYSTEM RESIDUALS Introduction Polycyclic aromatic hydrocarbons ( PAHs ) are known to occur in several different waste streams at low concentrations. Regulatory risk thresholds for some of the 16 PAH priority pollutants are very low due to their toxicity. The absence of sufficient scientific data on these PAHs has prevented scientist, engineers, and policy makers from making sound decision concerning reuse. Inflow of new scientif ic information has led to downward review of regulatory threshold for some of the PAHs over the years. Some of these new standards are lower than method detection limits used in previous scientific works (Townsend, 2002; FDEP, 2004) This scenario has rend ered the previous works inconclusive. A number of researchers across United States have conducted research into the extent of PAH contamination in various environmental matrix including street sweepings, catch basin sediments, stormwater pond sediments, f reshwater and estuarine sediments, recovered screen material (Johnson et al., 1985; Shiaris and Jambard Sweet, 1986; Miles and Delfino, 1999; Townsend, 2002) A r esearch on priority pollutant polycyclic aromatic hydrocarbons in Florida sed iments revealed the presence of PAH (Miles and Delfino, 1999) Sediment samples from freshwater and estuarine sites close to potential pollutant sources across Florida were sampled. Results showed that PAH compounds from molecular weight 178 (phenanthrene and anthracene) through molecular weight 252 (benz(a)anthracene and benzo(bk)fluoranthene ) were found most frequently. Mean measured concentrations

PAGE 34

34 ranged from 0.54 mg/kg ( acenophthylene ) to 33 mg/kg ( naphthalene ) The mean concentrations of benzo(a)pyrene and dibenzo(a,h )anthracene, which are of much concern, were 1.4 mg/kg and 0. 59 mg/kg respectively Johnson conducted a study on the distribution of PAHs in sedimen t s of Penobcot bay, Maine, USA (Johnson, et al., 1985) Fifty five sites were sampled and analyzed for PAH using HPLC and GC MS. Thirteen out of the 16 US EPA priority PAHs were detected in sediment samples from all the 55 sites. Fluorene was the only chemical detected in only 2 sites with concentration values of 0.00 6 m g/kg and 0.00 4 m g /kg. With the exception of fluoranthene and benzo(b)fluoranthene which had measured values exceeding 1.0 mg/Kg, the other PAH compounds investigated had concentrations ranging between 0.1 and 1.0 mg/Kg Also, i nvestigation of PAH loading in sediments of Boston Harbor, Massachuset ts, USA by Shiaris and Jambard Sweet (1986) reve a led the presence of PAH compounds. Twenty sites were sampled and analyzed for PAHs. High PAH concentration (>10.0 mg/Kg) were detected in samples from some of the sampled sites The mean benzo(a)pyrene conce ntration detected in one of the study sites was as high as 95 mg/Kg The high PAH concentration in the vicinity of Boston suggest the major input of PAH are from urban runoff. Some of the sampling sites were reported to be located next to Logan internation al Airport hence severely impacted by PAHs. As part of the effort to evaluate possible disposal and management option for street sweeping, stormwater sediment, and catch basin sediment in Florida, chemical characterization was performed (Townsend, 2002) A total of 300 samples were collected from 20 different sampling locations throughout Florida. Both total and

PAGE 35

35 leachable concentrations of metals and organics including PAHs were measured. Results of the total analysis showed the presence of 16 PAH chemical s in a number of the 300 samples Three compounds, benzo(a)anthracene, benzo(a)pyrene, and benzo(b)fluoranthene, were detected in two samples above both residential and industrial Florida soil cleanup target levels ( SCTLs ) The concentration of benzo(k)flu oranthene detected in 1 out of the 300 samples investigated exceeded the SCTLs for residential area. Indeno(1,2,3,c,d)pyrene was detected in 1 out of 300 samples, and this concentration exceeded both residential and industrial direct exposure criteria. The issue raised with the study was that, detection limits of 5 mg/L employed in the analysis was higher than direct exposure criteria for five PAHs including benzo(a)pyrene In the case of the leaching test, none of the PAHs chemicals investigated were detec ted above the detection limit of 10 g/L However, the detection limit (10 g/L) used was higher than the groundwater criteria for five PAH compounds including benzo(a)pyrene and indeno(1,2,3 c,d)pyrene. Evaluation of results by Florida Department of Envir onmental Protection (FDEP) concluded that additional studies may be required for some reuse applications (FDEP, 2004) The objective of this experiment was to investigate the concentration of PAHs in waste generated as part of routine maintenance and clean ing activities by utilities/private agencies. The potential risk associated with beneficial use of these waste streams is to be assessed. The waste streams considered for this study were : street sweepings, stormwater pond sediments, catch basin sediments, and ditch cleaning To accomplish this, representative samples were collected across the state of Florida and both total and leachable PAH concentrations measured. The arithmetic

PAGE 36

36 mean, geometric mean and the 95% upper confidence level ( UCL ) of the mean con centrations were determined and compared to corresponding regulatory threshold values. Sampling Location Ten samples each of ditch cleaning, stormwater sediments, catch basin sediments, and street sweepings were collected from fourteen cities across the state of Florida. Sampling sites were selected to cover the entire State of Florida. Sampling process was supported by the Public Works Departments of the various Cities. The sites are listed in Table 2 1 with corresponding site location shown in Figure 2 1. Figure 2 1 Study sites located in Florida

PAGE 37

37 Table 2 1 Sampling locations of sites investigated Site County City 1 Palm Beach Boynton 2 Lee Cape Coral 3 Volusia Daytona 4 St. Lucie Fort Pierce 5 Alachua Gainesville 6 Duval Jacksonville 7 Miam i Dade Miami Beach 8 Orange Orlando 9 Bay Panama City 10 Escambia Pensacola 11 St. Lucie Port St. Lucie 12 Highlands Sebring 13 Leon Tallahassee 14 Palm Beach West Palm Beach Material and Method Sample Collection Ten samples of roadway and storm s ystem residual (street sweeping, storm water pond sediment, catch basin sediment and ditch cleaning ) were collected For piled up waste s sampling piles were sectioned into quarters. Subsamples were generated by collecting approximately 20 g samples from 1 0 spots in each quarters using stainless scoop. Thirty centimeters (30 cm) surface depth was removed before sampling. Subsample from each quarter was thoroughly mixed in a steel bowl to constitute a composite sample. Approximately 500 g of composite sample w as transferred into glass jar with teflon coated cap. Labeled containers w ere stored below 4 o C in ice chests and transferred to the laboratory for storage below 4 o C prior to analysis. Cross contamination w as avoided by cleaning the sampling tools with d eionized water, liqui nox ( Alconox Inc., New York ), and isopropanol (Fisher Scientific Pittsburgh ) after each sampling event. Ditch and stormwater pond sed iments s amples w ere collected in the field using a steel auger. Random grid sampling technique w as u sed to obtain a representative sample. The site s w ere sectioned into grids and sediments taken

PAGE 38

38 approximately 30 cm below the surface in the grids and composted in a steel bowl. Labeled samples were similarly stored below 4 o C. Total PAH Extraction and Cle anup EPA Method 3550 and cleanup method reported by Marble and Delfino (Marble and Delfino, 1988) w ere employed in extraction and cleanup of samples Sample (30 g) w as weighed into 300 ml beaker and mixed with 60 g of anhydrous sodium sulfate thoroughly u sing stainless steel spatula. 1m L benzo(b)chrysene surrogate (4 .7 mg/L) standard w as added, and then followed by addition of 100 mL methylene chloride. Sample w as extracted ultrasonically using Sonicator model W 375 (Heat System Ultrasonics Inc Plainview NY. USA ) for 3 mins at 100% power output, 50% duty cycle, and pulsing energy. The extract w as decanted through a filter paper (Whatman 1) into a 400 mL beaker. The procedure w as repeated two more times and extracts combined. The combined extract w as conc entrated to 5 mL using nitrogen Turbo Vap II Concentration Workstation (Zymark Corporation) and solvent exchanged to acetonitrile using Kuderna Danish (KD) apparatus. The crude extract w as purified by solid phase extraction using 3 mL C18 octadecyl columns ( Varian Inc. ). An amount of 0. 2 5 g c opper powder (Fisher Scientific Pittsburgh ) w as added to the top of the column to remove any sulfur present in the extract. The column w as first conditioned by passing 3 mL methanol (Fisher Scientific) followed by 3 mL deionized water through it. Crude sample ( 1 mL) w as mixed with 2 mL deionized water in the column reservoir and the mixture pulled through C18 SPE column by vacuum. The C18 column w as dried under vacuum for 2 0 mins (Marble and Delfino, 1988) The PAHs analy tes w ere subsequently eluted using 3 mL of solvent mixture consisting of dichloromethane hexane acetonitrile (50:47:3 v:v:v).

PAGE 39

39 The solvent of the eluent w as exchanged to acetonitrile by employing the use of KD apparatus and final volume made up to 1mL pr ior to analysis Leachable PAHs Determination EPA Method 1312, the synthetic precipitation leaching procedure (SPLP), which is a method designed to simulate natural precipitation was used Th e SPLP method is used to evaluate potential for leaching of cont aminant into ground water and surface water. The extraction fluid consist ed of a mixture of H 2 SO 4 / HNO 3 (v:v) with pH adjusted to 4.2 0.05. Sample (200 g) w as weighed into a 2 Liter glass jar with Teflon lined lid. SPLP extraction solution 2 Liters w as added and t he sealed jar rotated for 18 hours. The leachate w as filtered using a stainless pressure filter containing glass fiber filter. This step w as followed by liquid liquid extraction of filtered sample (EPA method 3510C). Sample (1 L) w as measured w ith a graduating cylinder into a separator y funne l 1 m L benzo(b)chrysene surrogate ( 9.4 standard was added and extracted with 60mL methylene chloride by shaking the funnel Extraction step with methylene chloride w as repeated two more times. The separated organic layer w as dried over 60g sodium sulfate (Fisher Sceintific) concentrated to 5mL using nitrogen Turbo Vap II Concentration Workstation (Zymark Corporation) The concentrated extract was solvent exchanged with KD apparatus and cleaned using C18 SPE cartridge The final cleaned extract volume was made up to 1 mL. Analysis of Extracts by HPLC The analysis of the extracted sample for PAHs chemicals w as conducted by employing the use of a reverse phase high performance chromatography sys tem (Hitachi) consisting of L 7100 pump coupled with L 7200 autosampler, L 7400 UV

PAGE 40

40 detector and L 7485 Fluorescence detector. The HPLC was equipped with Brownlee Analytical PAH 5um column (Perkin Elmer). Acetonitrile and water (60:40), v/v) w as used as elu ent at 0.7 ml/min (in gradient condition). Detection of eluted 16 US EPA priority PAHs w as accomplished by using a fluorescence detector in the case of batch leaching studies and UV detector for total PAHs studies Quantitative determination of PAHs w as ac hieved using external standard calibration curve method. Quality Control/ Quality Assurance A set of activities were followed to ensure data integrity and address errors. Quality control procedure outlined in the EPA SW 846 test method manual was followed (EPA, 2007). A reagent blank was prepared and analyzed with every batch of samples. Replicate sample were spiked with identical concentration of standard PAHs A duplicate spiked sample was analyzed every 20 samples. A surrogate compound was added to all samples prior to extraction to help monitor extraction efficiency. Precision which is a measure of the agreement among a set of replicate measurements was also determined using the equation given below: where X 1 and X 2 are dupli cate samples The accuracy of the method was also monitored. Accuracy is a measure of the closeness between an observed value and an accepted reference value. Samples were spiked with known PAH standards and the recovery of the spike calculated using the e quation below where X s = m easured value of spiked sample, X u = m easured value of unspiked sample and K = Known value of spike in sample

PAGE 41

41 The method detection limit (MDL) was determined from seven replicate spikes using th e equation below. Where S = Standard deviation and t(n sided t statistics Statistical Analysis The results for both total and batch studies were checked for normality by using Sigma Plot. Non normal data set were normalized by employing log trans formation. The mean of the log transformed data was calculated and then converted back to obtain the geometric mean. The geometric mean (GM) was calculated using the expression: where GM = geometric mean, n = number of data points x = data values. The 95 % upper confidence levels (UCL) for the mean were calculated using the expression : where SD = standard deviation of the data, n = number of data points, t 0.05, n 1 = t value statistic at 0.05 for n 1 deg rees of freedom Results and Discussions Results from the quality assurance/ quality control procedure and total PAH analysis are summarized in T able s 2 2 to 2 7 Also, results of batch studies on these samples are summarized in T able 2 8 to table 2 11 A ll analytical data including moisture content, are presented in appendix A Normality check results for both total and batch studies Histograms of the distribution of the various PAH compounds were plotted after checking for normality The plot showing t he distribution PAHs in catch basin samples are presented in Appendix B 3 to B 17. The 95 % upper confidence

PAGE 42

42 levels (UCL) for the mean were calculated and presented as part of the summary results (Table 2 2 to 2 7) Quality Control/Quality Assurance Result s Quality Assurance/ Quality Control (QA/QC) plan involv ed analysis of spikes, duplicates, and blanks samples Table s 2 2, 2 3 and Table A 1, A 2 show the precision and accuracy of the analyses of samples. The measured values of PAH concentrations showed g ood precision which was within +20 % in almost all cases with very few exceptions. With the exception of few compounds, t he spiked recovery ranged between 71.0 to 117.2 % (UV detector) and 73.5 to 127.7 % (Fluorescence detector) indicating good accuracy. T otal Polycyclic Aromatic Hydrocarbons All the 16 polycyclic aromatic hydrocarbons investigated were detected in measurable quantities in ditch cleaning, stormwater pond sediment, catch basin sediments, and street sweeping sediments For the ditch cleaning sediments, the PAH with the highest detected concentration was Acenaphthene, with mean concentration values of 0.45 mg/Kg (arithmetic ) and 0.01 6 mg/Kg (geometric ) (T able 2 4 ) These values are below both the residential and industrial Soil Cleanup Target L evel (SCTL) of 2 400 mg/Kg and 20,000 mg/Kg respectively. Benzo(a)pyrene was detected in 6 out of the 10 ditch cleaning samples analyzed. The maximum conce ntration of b enzo(a)pyrene detect ed was 0.39 mg/Kg. The measured benzo(a)pyrene concentration in o ne of the samples (0.39 mg/Kg) was higher than residential SCTL (0.1 mg/Kg) This measured value was however lower than the industrial SCTL(Table 2 4). With the exception of benzo(a)pyrene, none of the PAHs investigated was detected above both the residential and industrial SCTLs.

PAGE 43

43 Analysis of the stormwater sediment did not yield any detect ed value for acenaphthylene. All other PAHs investi gated were detected in measura ble quantities. Benzo(a)pyrene was detected in 4 out of the 10 stormwater sediments samples analyzed Three out of the 4 benzo(a)pyrene concentrations measured were above the residential SCTLs (0.1 mg/Kg). One detect ed value exceeded the industrial SCTL (0.7 mg/Kg) (Table 2 5) None of the other detect ed s exceeded the corresponding residential and industrial SCTLs. In the case of street sweeping sediment samples, half of the 16 PAHs investigated were detected in 7 or more samples. Out of 10 street sweeping samples analyzed, 8 detected concentrations were recorded for phananthrene, anthracene, fluor anthene benzo(g,h,i)perylene and benzo(a)pyrene. In the case of benzo(a)pyrene, 7 out of the 8 measured values were above the residential SCTL ; with 1 of the values (1.4 mg/Kg) being above the Florida industrial SCTL as well (Table 2 6) The geometric mea n (0.12 mg/Kg) and the calculated 9 5 % UCL (1.4 mg /Kg) for benzo(a)pyrene were all above the residential SCTL, with the 9 5 % UCL value being above the industrial SCTL as well. Analysis of the catch basin sediments yielded detection of 14 out of 16 PAH compou nds investigated ( Table 2 7 ) With the exception of benzo(a)pyrene, all detect ed PAH compounds from the catch basin sediment analysis were lower than their corresponding Florida SCTLs. Seven samples had measured benzo(a)pyrene concentrations which were hig her than Florida residential SCTL Two measured benzo(a)pyren e concentrations ( 2. 1 mg/Kg and 3.4 mg /Kg) out of the 7 detections recorded were higher the industrial SCTL (0.7 mg/Kg) In spite of this, the geometric mean ( 0.04 mg/Kg ) was lower the Florida SC TL.

PAGE 44

44 Leaching of Polycyclic Aromatic Hydrocarbons Batch study conducted using synthetic precipitation leaching procedure ditch cleaning, stormwater pond sediments, catch basin sediments and street sweeping samples revealed low but measurable PAH concentrat ions using HPLC equipped with fluorescence detector. For the ditch cleaning samples, 7 PAHs chemicals (naphthalene, ace na phthylene, fluorene, chrysene, benzo(a)anthracene, dibenzo(a,h)anthracene, and indeno(1,2,3 cd)pyrene) were below the instrument detect ion limit ( Table 2 8) All other 9 PAH contaminants detected were all below their corresponding GWCTLs. For example, the geometric mean o f benzo(a)pyrene (0. 80 n g/L) was 3 order of magnitude lower than the corresponding GWCTLs For the stormwater pond sedim ent, 4 PAH contaminants (naphthalene, acenaphthylene, chrysene, and dibenzo(a,h)anthracene) were below method detection limits. The 10 PAH detected in measurable quantities were all below their corresponding GWCT L s. The GWCTL for benzo(a)pyrene for exampl e is 12 times higher than the geometric mean of concentrations recorded (Table 2 9) The greatest number of detects were recorded in the street sweeping sample study. Two PAHs contaminants (fluoranthene, pyrene, benzo(g,h,i)perylene and benzo(a)pyrene) w ere detected in all 10 street sweeping samples studied. One benzo(a)pyrene concentration ( 2 82 5 n g/L) was higher the GWCTL (Table 2 10) The geometric mean (1 6 6 n g/L) was however lower than the corresponding GWCTL (0.2 The trend for the catch basin sediment was not much different from those of ditch cleaning and stormwater samples Eleven PAH contaminants of interest were detected in measurable quantities. Benzo(k) fluoranthene was detected in all 10 catch basin

PAGE 45

45 s ediments studied. A ll detect ed values were below their corresponding GWCTLs, with benzo(a)pyrene being two order of magnitude lower than the GWCTL (Table 2 11) Comparison of Results with Published Literature The results in this study compares favorably wi th values reported by Johnson et al. ( 1985) The focus of the Johnson et al. (1985) study was on distribution of PAHs in sediments of Penobcot Bay located in Maine, USA. The stormwater and ditch cleaning samples were especially close to results in the John son et al. (1985) stud y, with results in this s tudy being slightly higher or lower valus reported (Tables 2 4 and 2 12) The mean concentration values reported by Johnson et al. (1985) were between 12 times higher to 3 times lower than the ditch cleaning a nd stormwater pond values (Table s 2 4 and 2 12) The street sweeping concentration values were in this study were 1.2 to 55 times higher than values reported by Johnson et al. (1985) (Table s 2 6 and 2 12) Also, catch basin sediment samples were 1.4 to 32 times higher higher than values published by Johnson et al. (1985) (Tables 2 7 and 2 12) Comparing this study results to values reported by Shiaris and Jambard Sweet (1986), values in this study were mostly lower than concentration ranges reported by Shi aris and Jambard Sweet ( 1986) Also, valu e s reported by Mil e s and Delfino (1999) were relatively higher than values obtained in this study (Table s 2 4 to 2 7 and 2 12) The ditch cleaning and stormwater values in this study were mostly between 2 to 3 orde rs of magnitude lower than values obtained by Mile s and Delfino (1999) The street sweeping and catch basin values on the other hand, were mostly 1 to 2 orders of magnitude lower than values reported by Mil e s and Delfino ( 1999) A similar study conducte d by Townsend (2002) on the same types of environmental matrices revealed fewer detects of PAH compounds The higher number

PAGE 46

46 of detect ed compounds in this study may be due to lower detection achieved using HPLC equipped with both UV and fluorescence detecto rs. For example, the benzo(a)pyrene detection limit in the in this study. The use of benzo(a)pyrene detection limit of 5000 study would not have yielded any excedance of the SCTL in terms of benzo(a)pyrene. In the Townsend study, the number of individual PAH compounds detect ed in the 300 samples analyzed ranged from 1 to 17 samples (0.3 to 5.7 %) (Tables 2 13 ) In this study, as high as 9 out of 10 samples (90 %) recorded PAH detection. Inspi te of the high number of PAH detect ions the measured concentrations were all lower than regulatory SCTLs thresholds except for benzo(a)pyrene. The measured maximum PAH concentrations in stormwater sediment s street seepings, catch basin sediments, and dit ch cleaning s in this study were 1 to 2 orders of magnituide lower than maximum concentrations reported by Townsend (2002) (Tables 2 4 to 2 7 and 2 1 3 ) For the leaching studies, PAHs were detected in measurable quantities using lower detection limits compa red to the Townsend (2002) study in which higher detection limits were used. PAHs investigated in the Townsend study were not detected. The geometric means of the measured PAHs were below Florida GWCTLs. These results supports observations in the Townsend (2002) study that PAHs in roadway and storm system residuals do not exceed regulatory SCTLs. Also, this study results confirms the earlier conclusion that PAHs do not leach out of roadway and storm system residuals above Florida GWCTLs. This study which w as conducted on 10 samples collected across Florida showed that concentrations of PAHs in ditch cleaning s, catch basin sediment s and stormwater

PAGE 47

47 sediments were below both residential and industrial SCTLs. Benzo(a)pyrene, which is of much concern due to its carsinogenic characteristic, was detected below both residential and industrial SCTLs. This observation based the 10 samples analysed suggests that PAHs may pose minimal direct exposure risk when used beneficially in residential or industrial areas based on risk assessment using Florida SCTLs Street sweeping s on the other hand, may likely pose direct exposure risk due to the geometric mean of benzo(a)pyrene being higher than SCTL Detected geometric mean of benzo(a)pyrene concentration was 1.2 times hig her than residential SCTL but 6 times lower than industrial SCTL. Beneficial use of street sweepings in industrial areas may pose minimal direct exposure risk based on data generated from the 10 s treet sweeping analys ed Beneficial use in residential area may be limited due to benzo(a)pyrene being higher than SCTL The roadway and storm system residual considered in this study did not leach PAH above the Florida GWCTLs. This implies that they are unlikely to leach PAHs to contaminate groundwater based on d ata generated from the 10 samples studied. Prior to this study, risk assessment on this waste had covered metals and some selected organic pollutants. Risk assessment of PAHs was inconclusive due to the detection level employed in the previous study. Thou gh some of the PAH compounds investigated were reported as being below detection limits, these detection limits were above regulatory threshold necessitating futher studies. For example, the detection limit for benzo(a)pyrene (5 mg/Kg) in the study was hig her than Florida residential SCTL (0.1 mg/Kg). Also, the waste streams have been characterized individually unlike the previous study were they were risk assessment involved all waste put together.

PAGE 48

48 Summary and Conclusion To address the question of direct exposure risk of PAHs and their potential leaching into groundwater from roadway and storm system residuals, 10 samples each of roadway and storm system residuals (ditch cleaning, stormwater pond sediment, catch basin sediment and street sweeping) w ere collected across Florida and analyzed for PAHs Sixteen US EPA priority PAHs were detected in varying concentrations and detects in the waste materials. Benzo(a)pyrene was detected in 4 stormwater pond sediments, 6 ditch cleaning sediments, 7 catch bas in sediments, and 8 street sweeping samples. B enzo(a)pyrene measured in ditch cleaning, stormwater pond sediment an d catch basin sediments were 3 to 50 times lower than residential SCTL. Also the m easured concentrations were 18 to 350 times lower than indu strial SCTL. Benzo(a)pyrene measured in s treet sweepings was 1.2 times higher than residential SCTL but 6 times lower than industrial SCTL. Batch leaching studies yielded measurable PAH concentrations from the roadway and storm system residuals. With the exception of street sweeping samples, none of the detects exceeded the GWCTLs. Two street sweeping samples leached benzo(b ) fluoranthene above GWCTL. One out of the two samples leached benzo(a)pyrene above the GWCTL as well. However, geometric means were o n e order of magnitude lower than the GWCTLs. All roadway and storm system residual samples investigated had measured PAH concentrations below the GWCTLs, the residential SCTLs and industrial SCTL except the street sweeping sample which recorded benzo(a)pyr ene higher than residential SCTL This observation suggests that beneficial use of ditch cleaning, stormwater pond sediment, and catch basin sediment in both residential and industrial area may pose minimal PAH direct exposure risk based on risk assessment using Florida SCTLs. Since

PAGE 49

49 the results obtained for benzo(a)pyrene in street sweepings was relatively close to the SCTL, it behooves that other factors considered in the development of SCTL be investigated to better assess potential risk. One good example is fraction of pollutant bioaaccessible which is assumed to be one hundred percent in the SCTL. This is the subject discussed in chapter 5. Beneficial use of street sweepings in industrial areas may pose minimal direct exposure risk based on data generat ed from the 10 street sweeping analysed. Beneficial use in residential area may be limited due to benzo(a)pyrene being higher than residential SCTL. The roadway and storm system residual considered in this study are unlikely to leach PAHs to contaminate gr oundwater which is the major source of drinking water in Florida. This study was conducted on 10 samples of each waste stream. Future work involving a larger sample size across the state of Florida would give results which would be more representative of t he extent of PAH contamination across the State.

PAGE 50

50 Table 2 2 Results of spike recovery, relative percentage difference (RPD) and method detection limit (MDL) using UV detector. Mean MDL Residential Industrial PAH Chemicals Recovery (%) R P D (%) ( g/Kg) SCTL mg/Kg SCTL m g/Kg Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoran thene Indeno (1,2,3 cd) pyrene 72.4 65.4 68.2 76.6 72.8 75.1 117.2 87.9 73.6 104.5 77.4 81.0 62.6 72.4 71.0 98.7 9.3 7.8 1.4 13.4 15.2 0.6 8.2 1.2 1.3 25.5 11.1 11.2 1.5 7.4 23.1 22.9 2.5 2.5 4.9 0.5 0 0.2 0 0.1 0 0.2 0 0.5 0 0.1 0 0.2 0 0.4 0 0.2 0 0.2 0 1.0 0.1 0 0 .2 0 55 1 800 2 400 2 600 2 200 2 100 3 200 2 400 2500 0.1 300 20 000 20 000 33 000 36 000 300 000 59 000 45 000 52 000 0.7 Table 2 3 Results of spike recovery and method detection limit using Fluorescence detector. Recovery MDL G WCTLs PAH Chemicals (%) (n g/L) ( n g/L) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 62.6 63.6 127.7 73.5 82.5 108.7 84.0 81.6 82.6 76.8 64.5 86.4 78.4 86.5 80 3 500 14 1 6 10 0 7 0 0 8 0 0 2 0 0 4 0 1 1 0 3 0 0 3 0 0 1 0 0 1 0 14 ,000 210 ,000 20 ,000 280 ,000 210 ,000 2 100 ,000 280 ,000 210 ,000 5 00 4, 8 00 210 ,000 2 00 5 0 5 5 0 5 0 Compounds not investigated in this study.

PAGE 51

51 Table 2 4 Mean total concentrations of ditch cleaning samples using UV detector (mg/Kg) No of No. of Max 9 5 % Mean Mean Residential Industrial No of PAH Chemicals Sample s Detect ions Conc. (mg/Kg ) UCL (mg/Kg ) Arithmeti c (mg/Kg) Geometri c (mg/Kg) SCTL (R SCTL) (mg/Kg) SCTL (I SCTL) (mg/Kg) Exceedance R SCTL (I SCTL) Naphthalene 10 5 1. 7 0.22 0. 2 2 0. 016 55 300 Acenaphthylene 10 2 0.3 1 0.0 3 0.04 0.003 1 800 20 000 Acenaphthen e 10 3 2. 9 0.27 0.4 5 0.016 2 400 20 000 Fluorene 10 2 0.02 0.003 0.004 0.001 2 600 33 000 Phenanthrene 10 6 0.44 0.08 0.06 0.004 2 200 36 000 Anthracene 10 7 0.07 0.0 3 0.01 0.002 2 100 300 000 Fluoranthene 10 6 1.0 0.47 0.2 1 0.010 3 200 59 000 Pyrene 10 6 0.7 9 0.29 0.1 4 0.012 2 400 45 000 Benzo (k) Fluoranthene 10 5 0.08 0.0 2 0.01 0.001 Chrysene 10 6 0.66 0.22 0.11 0.007 Benzo (g,h,i)perylene 10 6 2.75 0.80 0.43 0.019 2 500 52 000 Benzo (a)pyrene 10 6 0.3 7 0.17 0.0 8 0.006 0.1 0.7 1 (0) Benzo (a) anthracene 10 6 0.5 3 0.16 0.0 9 0.006 Dibenzo (a,h) anthracene 10 2 0.26 0.0 1 0.0 4 0.0002 Benzo (b) fluoranthene 10 5 0.13 0.04 0.0 3 0.001 Indeno (1,2,3 cd) pyrene 10 3 0.08 0.0 2 0.02 0.001

PAGE 52

52 Table 2 5 M ean total concentrations of stormwater pond samples using UV detector (mg/Kg) No of No. of Max 9 5 % Mean Mean Residential Industrial No of PAH Chemicals Samples Detect ions Conc. (mg/Kg) UCL (mg/Kg) Arithmetic (mg/Kg) Geometric (mg/Kg) SCTL (mg/Kg) SCTL (mg/Kg) Exceedance Naphthalene 10 2 6.3 0.07 0.78 0.005 55 300 Acenaphthylene 10 0 <0.003 <0.003 <0.003 <0.003 1 800 20 000 Acenaphthene 10 1 0.73 0.02 0.0 8 0.004 2 400 20 000 Fluorene 10 2 0.0 4 0.004 0.01 0.001 2 600 33 000 Phenanthrene 10 6 2.0 0.10 0.21 0.004 2 200 36 000 Anthracene 10 6 0.24 0.02 0.0 3 0.001 2 100 300 000 Fluoranthene 10 7 3.4 1.5 0.57 0.031 3 200 59 000 Pyrene 10 7 3.1 0.35 0.35 0.017 2 400 45 000 Benzo (k) Fluoranthene 10 6 0.22 0.0 4 0.03 0.002 Chrysene 10 5 1.8 0.12 0.20 0.003 Benzo (g,h,i)perylene 10 6 4.6 0.88 0.60 0.019 2 500 52 000 Benzo (a)pyrene 10 4 1.7 0.0 9 0.20 0.002 0.1 0.7 3 (1) Benzo (a) anthracene 10 4 1.1 0.06 0.13 0.002 Dibenzo (a,h) anthracene 10 2 0.79 0.0 1 0.09 0.0003 Benzo (b) fluoranthene 10 4 0.39 0.0 2 0.04 0.001 Indeno (1,2,3 cd) pyrene 10 7 1.1 0.25 0.15 0.010

PAGE 53

53 Table 2 6 Mean total concentrations of street sweeping samples using UV detector (mg/Kg) PAH Chemicals No of Samples No. of Dete ctions Max Conc. (mg/Kg) 95% UCL (mg/Kg) Mean Arithmetic (mg/Kg) Mean Geometric (mg/Kg) Residential SCTL (mg/Kg) Industrial SCTL (mg/Kg) No of Exceedance Naphthalene 10 6 6.7 4.4 1.4 0.17 55 300 Acenaphthylene 10 0 <0.003 <0.003 <0.003 <0.003 1 800 20 000 Acenaphthene 10 1 6.3 0.58 1.2 0.02 2 400 20 000 Fluorene 10 0 <0.001 <0.001 <0.001 <0.001 2 600 33 000 Phenanthrene 10 8 0.81 1.0 0.27 0.088 2 200 36 000 Anthracene 10 8 0.20 0.21 0.06 0.0 2 2 100 300 000 Fluoranthene 10 8 6.0 6.2 1.3 0.35 3 200 59 000 Pyrene 10 7 2.4 2.5 0.61 0.11 2 400 45 000 Benzo (k) Fluoranthene 10 7 0.23 0.22 0.0 6 0.01 Chrysene 10 6 1.8 2.1 0.46 0.07 Benzo (g,h,i)perylene 10 8 7.7 5.5 1.5 0.37 2 500 52 000 Benzo (a)pyrene 10 8 1.4 1.4 0.38 0.12 0.1 0.7 7 (1) Benzo (a) anthracene 10 7 1.8 1.4 0.36 0.05 Dibenzo (a,h) anthracene 10 2 0.72 0.21 0.27 0.002 Benzo (b) fluoranthene 10 5 0.36 0.31 0.09 0.01 Indeno (1,2,3 cd) pyrene 10 2 0.36 0.0 5 0.12 0.001

PAGE 54

54 Table 2 7 Mean total concentrations of catch basin samples using UV detector (mg/Kg) No of No. of Max 9 5 % Mean Mean Residentia l Industria l No of PAH Chemicals Sample s Detect ions Conc. (mg/Kg ) UCL (mg/Kg ) Arithmeti c (mg/Kg) Geometri c (mg/Kg) SCTL (mg/Kg) SCTL (mg/Kg) Exceedanc e Naphthalene 10 6 2.0 1.3 0.57 0.0 6 55 300 Acenaphthylene 10 0 <0.003 <0.003 <0.003 <0.003 1 800 20 000 Acenaphthene 10 4 6.6 0.87 1.1 0.03 2 400 20 000 Fluorene 10 0 <0.001 <0.001 <0.001 <0.001 2 600 33 000 Phenanthrene 10 8 1.1 0.6 8 0.23 0.03 2 200 36 000 Anthracene 10 8 0.56 0.25 0.20 0.01 2 100 300 000 Fluoranthene 10 9 2.7 8. 6 1.5 0.47 3 200 59 000 Pyrene 10 5 0.97 0.70 0.60 0.01 2 400 45 000 Benzo (k) Fluoranthene 10 9 0.35 0.42 0.12 0.0 4 Chrysene 10 5 2.3 0.59 0.42 0.0 1 Benzo (g,h,i)perylene 10 7 12 10 2.7 0.14 2 500 52 000 Benzo (a)pyrene 10 7 3.4 2.1 0.69 0.0 4 0.1 0.7 7 (2) Benzo (a) anthracene 10 7 2.8 1.2 0.46 0.0 3 Dibenzo (a,h) anthracene 10 3 0.88 0.050 0.16 0.001 Benzo (b) fluoranthene 10 7 0.50 0. 40 0.11 0.01 Indeno (1,2,3 cd) pyrene 10 5 0.19 0.11 0.060 0.003

PAGE 55

55 Table 2 8 Mean leached concentrations of ditch cleaning samples using fluorescence detector (ng/L) No of No. of Max 9 5 % Mean Mean GWCTLs No of PAH Chemicals Samples Detect ions Conc. (ng/L) UCL (ng/L) Arithmetic (ng/L) Geometric (ng/L) (ng/L) Exceedance Naphthalene 10 0 <80 <80 <80 <80 14 ,000 0 Acenaphthylene 10 0 <3,500 <3,500 <3,500 <3,500 210 ,000 0 Acenaphthene 10 8 2 7 0 3 2 0 1 1 0 377 20 ,000 0 Fluorene 280 ,000 Phenanthrene 10 8 2 7 16 8 7 5 2 210 ,000 0 Anthracene 10 6 2 1 12 7 5 5 8 2 100 ,000 0 Fluoranthene 10 7 4 5 46 20 5 9 280 ,000 0 Pyrene 10 9 22 2 6 12 0 8 7 210 ,000 0 Benzo(k)f luoranthene 10 8 1 1 1 4 0 76 0 52 5 00 0 Chrysene 10 0 <0.40 <0.40 <0.40 <0.40 4, 8 00 0 Benzo (g,h,i)perylene 10 4 3 5 14 9 5 2 4 210 ,000 0 Benzo(a)pyrene 10 5 13 5 2 3 2 0 80 2 00 0 Benzo(a) anthracene 10 0 <0.30 <0.30 <0.30 <0.30 5 0 0 Dibenzo(a,h)anthracene 10 0 <0.10 <0.10 <0.10 <0.10 5 0 B enzo (b) fluoranthene 10 6 8 2 5 8 2 7 0 7 0 5 0 0 Indeno (1,2,3 cd) pyrene 5 0 Compounds not investigated in this study.

PAGE 56

56 Table 2 9 Mean leached concentrations of stormwater pond samples using fluorescence detector (ng/L) No of No. o f Max 9 5 % Mean Mean GWCTLs No of PAH Chemicals Samples Detect ions Conc. (ng/L) UCL (ng/L) Arithmetic (ng/L) Geometric (ng/L) (ng/L) Exceedance Naphthalene 10 0 <80 <80 <80 <80 14 ,000 0 Acenaphthylene 10 0 <3,50 0 <3,500 <3,500 <3,500 210 ,000 0 Acena phthene 10 8 3058 3 1 291 5 706 8 171 8 20 ,000 0 Fluorene 280 ,000 Phenanthrene 10 5 20 3 13 0 7 3 3 2 210 ,000 0 Anthracene 10 1 14 5 7 7 6 0 5 7 2 100 ,000 0 Fluoranthene 10 5 71 9 44 8 24 2 3 9 280 ,000 0 Pyrene 10 9 44 8 43 6 19 5 11 1 2 10 ,000 0 Benzo (k) Fluoranthene 10 9 4 5 2 4 1 3 0 6 5 00 0 Chrysene 10 0 <0.40 <0.40 <0.40 <0.40 4, 8 00 0 Benzo (g,h,i)perylene 10 3 42 6 10 5 9 6 1 7 210 ,000 0 Benzo (a)pyrene 10 5 17 5 9 6 5 5 1 1 2 00 0 Benzo (a) anthracene 10 1 1 5 0 4 0 3 0 2 5 0 0 Dibenzo (a,h) anthracene 10 0 <0.10 <0.10 <0.10 <0.10 5 0 Benzo (b) fluoranthene 10 5 15 1 4 7 3 4 0 5 5 0 0 Indeno (1,2,3 cd) pyrene 5 0 Compounds not investigated in this study.

PAGE 57

57 Table 2 10 Mean leached concentrations of street sw eeping samples using fluorescence detector (ng/L) SS No of No. of Max 9 5 % Mean Mean GWCTLs No of PAH Chemicals Samples Detect ions Conc. (ng/L) UCL (ng/L) Arithmetic (ng/L) Geometric (ng/L) (ng/L) Exceedance Naphthalene 10 4 5 782 0 2 339 9 1 695 3 249 8 14 ,000 0 Acenaphthylene 10 0 <3,500 <3,500 <3,500 <3,500 210 ,000 0 Acenaphthene 10 5 1 206 1 501 0 297 0 57 6 20 ,000 0 Fluorene 280 ,000 Phenanthrene 10 7 151 5 93 0 53 9 10 7 210 ,000 0 Anthracene 10 2 957 3 64 9 110 7 11 7 2 100 ,000 0 F luoranthene 10 10 971 2 345 3 211 5 107 0 280 ,000 0 Pyrene 10 10 422 0 152 2 94 0 51 1 210 ,000 0 Benzo (k) Fluoranthene 10 9 11 4 6 2 3 2 1 6 5 00 0 Chrysene 10 5 187 8 39 1 31 3 2 7 4, 8 00 0 Benzo (g,h,i)perylene 10 10 668 5 212 6 144 9 62 6 210 ,000 0 Benzo (a)pyrene 10 10 282 5 82 1 53 8 16 6 2 00 1 Benzo (a) anthracene 10 1 2 6 0 4 0 4 0 2 5 0 0 Dibenzo (a,h) anthracene 10 0 <0.10 <0.10 <0.10 <0.10 5 0 Benzo (b) fluoranthene 10 8 117 4 55 0 25 3 4 5 5 0 2 Indeno (1,2,3 cd) pyrene 5 0 Compounds not investigated in this study.

PAGE 58

58 Table 2 11 Mean leached concentrations of catch basin samples using fluorescence (ng/L) CB No of No. of Max 9 5 % Mean Mean GWCTLs No of PAH Chemicals Samples Detect ions Conc. (ng/L) UCL (ng/L) Arithmetic ( ng/L) Geometric (ng/L) (ng/L) Exceedance Naphthalene 10 2 3 760 6 597 9 777 5 99 0 14 ,000 0 Acenaphthylene 10 0 <3,500 <3,500 <3,500 <3,500 210 ,000 0 Acenaphthene 10 9 2 632 8 1 802 8 871 7 327 1 20 ,000 0 Fluorene 280 ,000 Phenanthrene 10 7 56 7 23 7 13 0 5 7 210 ,000 0 Anthracene 10 2 33 7 13 6 7 5 4 6 2 100 ,000 0 Fluoranthene 10 8 119 1 135 5 45 9 17 5 280 ,000 0 Pyrene 10 9 65 4 62 0 26 9 13 9 210 ,000 0 Benzo (k) Fluoranthene 10 10 5 6 3 4 2 1 1 6 5 00 0 Chrysene 10 1 0 7 0 3 0 3 0 2 4, 8 00 0 Benzo (g,h,i)perylene 10 8 117 1 106 4 42 2 16 7 210 ,000 0 Benzo (a)pyrene 10 7 23 7 19 0 8 0 2 6 2 00 0 Benzo (a) anthracene 10 0 <0.30 <0.30 <0.30 <0.30 5 0 0 Dibenzo (a,h) anthracene 10 0 <0.10 <0.10 <0.10 <0.10 5 0 Benzo (b) fluoranthene 10 7 13 1 10 5 4 4 1 2 5 0 0 Indeno (1,2,3 cd) pyrene 5 0 Compounds not investigated in this study.

PAGE 59

59 Table 2 12. Reported polycyclic aromatic hydrocarbons in literature Mills and Delfino (1999) Johnson and Larsen (1985) Shiaris and Ja mbart (1986) Townsend (2000) (mg/Kg) (mg/Kg) ( g/Kg) ( g/Kg) (mg/Kg) (mg/Kg) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) ant hracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 33 0.54 23 11 6.2 1.5 4.2 3.6 1.7 7.6 1.4 1.5 0.59 5.1 0.26 226 0.08 3.0 0.08 262 0.07 128 0.05 228 0.04 11 0.06 85 0.05 78 0.04 13 4.5 10.6 0.18 9.5 0.04 11 0.36 1.0 0.72 9.5 3 2 0 4 45 1 6 4 6 4 3 9 9 7 6 3 6 .0 1 .0 7 9 3 5 17 25 0 nd 49 156 37 00 16 539 14 696 9 .0 578 23 641 1 0 54 0 14 54 0 2 .0 12 0 17 1 0 00 9 .0 228 <0.01 45.6 0.45 63.7 <0.01 0.51 <0.005 84.5 0.16 66.8 <0.007 95 <0.07 4.10 6.5 7.5 29.1 12.9 5.4 59.3 11.6 111.2 22.2 7.6 48.5 9.2 34.3 14.5 39.9 13.2 104.1 47.2

PAGE 60

60 Table 2 13. PAH concentrations in street sweepings, stormwater pond sediment, and catch basin sediments reported by Townsend (2002) Analyte No. of Samples No. of Detections Concentration Range (mg/Kg) No. of Exceedance Residential Industrial SCTLs Residential Industrial (mg/Kg) (mg/Kg) Fluorene Phenanthrene Anthracene Fluor anthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 300 300 300 300 300 300 300 300 300 300 300 300 1 5 1 12 17 1 1 2 2 2 2 1 6.5 7.5 29.1 12.9 5.4 59.3 1 1.6 111.2 22.2 56.3 7.6 48.5 9.2 34.3 14.5 39.9 13.2 104.1 47.2 0 0 0 0 0 1 0 0 2 2 2 1 0 0 0 0 0 0 0 0 2 2 2 1 2 200 2 000 18 000 2 900 2 200 15 140 2 300 0.1 1.4 1.4 1.5 28 000 30 000 2 60 ,000 48 000 37 000 52 450 41 000 0.5 5 4.8 5.3

PAGE 61

61 CHAPTER 3 LEACH ING OF POLYCYCLIC AR OMATIC HYROCARBONS F ROM RECLAIMED ASPHALT PAVEMENT (RA P) AND MILLED SHINGL ES Introduction There is environmental concern relating to possible leaching of PAHs from asphalt products. PAHs are known components of asphalt and bitumen (Bran dt and de Groot, 2001; Legret et al., 2005; Birgistottir et al., 2007) There is concern that PAHs could leach out of recycled asphalt product when used beneficially or stockpiled for future use. Construction and expansion of asphalt roadways results in large amount of milled asphalt pavement known as reclaimed asphalt pavement (RAP). RAP is recycled back into new hot mix asphalt for road and packing lot construct. However, unused material remains on site for lon g periods until reuse options develop. An a lternate landfilling option is expensive due to stricter requirement for landfill operators (Brantley and Townsend, 1999) Suggested use of RAP as fill material in construction or reclaim borrow pits has been questioned due to potential leaching of PAHs. V arious researchers have attempted to answer the question of whether PAHs leach from asphalt waste and to what extent they do so (Brantley and Townsend, 1999; Brandt and de Groot, 2001; Legret, et al., 2005) Though experimental results showed the absence of PAH s in both batch and column studies in the Brandly and Townsend study (Brantley and Townsend, 1999) concerns have been raised about the data because regulatory thresholds have been lowered since then. Previous Research on RAP Leaching Studies on a que ous leaching of PAHs from bitumen and asphalt studies (Brandt and de Groot, 2001) revealed measurable leaching of PAHs. Static and dynamic tests were conducted on nine bitumen samples and one asphalt sample made utilizing one of

PAGE 62

62 the bitumen samples. The st atic test involved leaching an asphalt block and a glass dish covered with sample bitumen layers with acidified water. The dynamic test involved size reduction to <4mm, and leaching with acidified water (pH 4), with a liquid/solid ratio of 10:1, and agitat ing for 30 ho u rs at 30rpm. The equilibrium PAH concentrations in the leached water stayed well below the surface water and potable water limits in European Economic Countries (EEC). The benzo(a)pyrene concentrations in the leached water ranged from <0.015 to 0.3 ng/L compared to the limit of 10 ng/L in EEC countries. Studies conducted on leaching pollutants from reclaimed asphalt pavement did not reveal leaching of PAHs (Bran tley and Townsend 1999 ) The experiment was conducted on six reclaimed asphalt pa vement samples collected from sites across the state of Florida. Results of all samples analyzed in the experiment showed PAH levels below detection limits. Few concerns, however, have been raised about the outcome of the results. The detection limit for B enzo(a)pyrene (0.25g/L) was slightly higher than guidance concentration (0.20g/L). Secondly, although results were below detect ion limits and hence below regulatory guideline s in use at the time of research, lower new standards have been published. Exam ple, the GWCTL for b enz(a)anthracene has been lowered from 4g/L to 0.05g/L while the standard for d ibenz(a,h)anthracene has been lowered from 7.5g/L to 0.005g/L. To account for changes made to regulatory standards, further studies on this waste stream needs to be conducted using lower detection limits. Materials and Methods Column Leaching Studies Five samples of reclaimed asphalt pavement and one milled shingles were collected across Florida for the experiment (Figure 3 1 ). The samples were collected

PAGE 63

63 f rom asphalt pavement processing facilities and shingles recycling facility in various cities. Column and batch leaching studies were conducted on the collected samples. The experimental setup for the column leaching studies was designed to simulate more re alistic environmental conditions in the field. Leaching condition s of asphalt waste s w ere investigated using SPLP leaching solution. Two scenarios depicting saturated and unsaturated conditions were investigated The leaching solution f low rate in this exp eriment was chosen to mimic aggressive rainstorm in Florida (4 6 inch/hr). Figure 3 1 Study sites w here RAP and shingles were sampled Column design and setup The experimental setup consist ed of 16 stainless steel leaching columns (lysimeters). The co mponents of the lysimeter consist ed of stainless steel 6 inch diameter pipe, Teflon O rings, and stainless steel filter screen. Figure 3 2 shows the

PAGE 64

64 column setup for the experiment. SPLP leaching solution was pumped from a 10 gallon HDPE plastic reservoir using a multi channel pump into the individual columns. Prior to packing columns with sample, various cleaning steps were followed. The stainless steel columns were pre cleaned with deionized water, followed by 20% nitric acid rinsing. Next step was rinsin g with deionized water, followed by SPLP leaching solution rinsing. The filter screens were likewise rinsed with 20% nitric acid, followed by Figure 3 2 Column leaching apparatus deionized water rinsing. The cleaned filters were heated over night in an oven at 110 o C. Gravel and sand to be placed below and above the samples were washed with 20 % nitric acid, deionized water and heated in an oven at 110 o C over night. The stainless steel filters w ere placed at the bottom of the unit and approximately 6 inches of gravel

PAGE 65

65 was placed on top of it. S tainless steel screen w ere placed on top of the gravel and the columns were loaded with approximately 3 feet of sample with 3 inches of sand placed on top of it and then sealed. The purpose of the sand was to ens ure even distribution of SPLP solution. Column leaching tests Two leaching scenarios involving saturated and unsaturated conditions w ere investigated. For the unsaturated condition, SPLP leaching solution (1L) w as pumped into the columns at a flow rate of 50 mL/min (6.47 inch/hr) for 20 minutes per day. The flow rate was chosen to mimic aggressive rainstorm in Florida (4 6 inch/hr). Resulting l eachate w as drained immediately from the bottom of the columns. For the saturated condition, SPLP solution w as pu mp ed into the column until the solution was approximately 2 inches above the sample. A l eaching solution volume of 9.52L w as used to fill each column in the saturated condition setup. The leachate was completely drained and refilled with freshly prepared S PLP after 7 days. The experiment was run over 35 days The collected leachate w as stored in 1L amber glass bottles and stored at 4 o C prior to extraction. Leachate extraction Collected leachate was extracted using EPA Method 3510C 1L of leachate was measu red and 1m L benzo(b) chrysene ( g/L) surrogate was added. The sample w as transferred into a separatory funnel and extracted with 3 portions of 100mL methylene chloride. The separated organic layer w as dried over 60g sodium sulfate and concentrated to 5 mL by nitrogen blow method then purified using 3mL C18 SPE cartridge (Fisher Scientific). The column w as first con ditioned by passing 3 mL portion of methanol followed by 3mL deionized water Crude sample ( 1 mL) w as mixed with 3 mL

PAGE 66

66 deionized water in the colum n reservoir and pulled through the cartridge by vacuum. Vacuum dried cartridge was eluted with 3 mL solvent mixture consisting of dichloromethane hexane acetonitrile (50:47:3, v:v:v). The solvent w as exchanged to acetonitrile and the volume reduced to 1 mL prior to analysis with HPLC Batch Leaching Studies Synthetic precipitation leaching procedure (SPLP) leaching test s w ere conducted on samples ( US EPA Method 1312). The extraction fluid consists of a mixture of H 2 SO 4 / HNO 3 (v:v) with pH adjusted to 4.2 Sample (100g) w as weighed into a 2 Liter glass jar with a Teflon lined lid, and 2L SPLP solution was added and the jar was rotated for 18 hours. The leachate w as filtered using a stainless pressure filter containing glass fiber filter One liter of leac hate was measured into a separatory funnel, and 1m L benzo(b)chrysene ( g/L) surrogate was a d d ed and extracted with 3 portions of 100mL methylene chloride. The separated organic layer w as dried over 60g sodium sulfate. The extract w as concentrated to 5 mL by nitrogen blow method and purified using C18 SPE cartridge (Fisher Scientific Pittsburgh, PA, USA ) as described in chapter 2. Results and Discussions Physical Characterization Results The five R AP and one milled shingles samples were physically chara cterized. The characterization studies were conducted by the State material office of Florida department of transportation (FDOT) located in Gainesville, Florida. Physical tests conducted were; asphalt content, viscosity, penetration and gradation studies Test results are presented in table 3 1 and figure 3 3 All samples were of similar gradation except for the Gainesville ( GNV ) and Marianna ( MAR ) samples which were not well

PAGE 67

67 graded. GNV consisted of larger particles and had 60% of grains being 5 inches o r larger. The milled shingles had the highest asphalt content (27%). The asphalt content of the RAP samples ranged from 4.1 to 6.6%. Viscosity and penetration gives an indication of the age of the sample. Viscosity of virgin asphalt cement is approximately 3000 poise (Brantley and Townsend, 1999) Asphalt cement tends to harden with age hence viscosity increases with age. Also, penetration of asphalt cement decreases as it Table 3 1 Physical characteristics results Sample source Material Code Asphalt content (%) Viscosity at 60 o C (poise) Penetration at 25 o C (0.1 mm) Lake City Jacksonville Gainesville Pembroke Pine Marianna Bradenton RAP RAP RAP RAP RAP Shingles LC JAX GNV PEM MAR BRN 6.6 5.2 4.1 5.6 4.3 27.0 796,662 379,489 371,827 129,588 278,979 N/A 6.5 9.5 10.5 13 12.5 N/A hardens. Viscosity of all RAP samples indicate source being from an older roadway, with the Pembroke (PEM) sample being from a younger source. Lake City (LC) sample with the lowest penetration and highest viscosity was the ol dest sample. Quality Control/Quality Assurance (QA/QC) Quality Assurance/ Quality Control (QA/QC) plan involving spikes, duplicates, and blanks were followed. Table 3 2 show the precision and accuracy of the analyses of samples. The measured values of PAH concentrations showed good precision which was within 20% in almost all cases with very few exceptions. With the exception of a few compounds, the spiked recovery ranged between 7 2 to 1 01 % indicating good accuracy.

PAGE 68

68 Batch Leaching Results Batch study result of the milled shingle sample and 5 RAP samples are summarized in T able 3 3 Eight PAH contaminants were detected in leachate from the milled shingles. Detecte d concentrations ranged from 6 8 .0 n g /L (chrysene) to 735 .0 n g/L (fluoranthene). The benzo( a)pyrene concentration ( 166 .0 n g/L) was lower than GWCTL (2 00 .0 n g/L). Two detected PAH cont aminants, benzo(a)anthracene ( 325 .0 n g/L) and benzo(b)fluoranthene ( 104 .0 n g/L), were above their correspondin g GWCTL ( 5 0 .0 n g/L). While the measured benzo(a)anthra cene concentration value is 6.5 times higher than the GWCTL, that of benzo(b)fluoranthene was 2.1 times higher ( T able 3 3 ) Out of the 5 RAP samples studied, only one leached PAH in measurable quantities. The sample PEM ( T able 3 3 ) leached 8 PAH compounds with concentrations ranging from 3.0 ng/L (benzo(k)fluoranthene to 321 .0 n g/L (fluoranthene). None of the 8 detected PAHs were above their corresponding GWCTLs. The measured benzo(a)pyrene concentrati on ( 23 .0 n g/L) was one order of magnitude lo wer than cor responding GWCTL ( 2 00 n g/L). Also, measured v alues of benzo(a)anthracene ( 35 n g/ L) and benzo(b)fluoranthene ( 17 n g/L) were lower than t heir corresponding GWCTLs of 5 0 n g/L (table 3 2 ) Column Leaching Results Column study results are presented in T ables 3 3 Table s A 9 to A 22 in Appendix A and plotted in Figures 3 4 to 3 10. The study was conducted on one milled shingles sample and five RAP samples under saturated and unsaturated conditions. Varying results were obtained for the milled shingles and RAP s amples.

PAGE 69

69 Leaching under unsaturated condition The c olumn study conducted on the milled asphalt shingles and five RAP samples yielded measurable concentrations of some PAHs. Five PAH organic contaminants (fluoranthene, pyrene, benzo(k)fluoranthene, benzo(g,h ,i)perylene and benzo(a)pyrene) leached out of the column ( F igure s 3 4 to 3 8 ) The leaching characteristics followed a typical leaching curve. Fluoranthene leached out with an initial concentration of 0.23 nd leachin g event which was equivalent to a liquid solid ratio of (L/S) of 2 ( F igure 3 4 ) The measured concentration values of fluoranthene was well below the GWCTL of 280 Pyrene started leaching out of the column with a concentration of 0.086 but dropped to 0.03 liquid to solid ( L/S ) ratio of 2. The leached concentrations were also well below the GWCTL of 210 Benzo(a)pyrene, which started leaching out dropped below the detectable limit of 0.0003 y L/S of 2. The measured concentrations of benzo(a)pyrene were all below the GWCTL. The concentration of benzo(k)fluorathene dropped to 0.006 2) after initially leaching out with a concentration of 0.004 benzo(ghi)perylene leached out of the duplicate shingles column with an initial concentration of 0.023 the end of the leaching event. For the RAP sample column study, fluoranthene, pyrene, benzo(k)fluoranthe ne, benzo(g,h,i)perylene, benzo ( a)pyrene and benzo(b)fluoranthene leached out of two or more columns containing various RAP sample s Fluoranthene leached out of the columns containing RAP samples LC GNV, PEM and MAR with initial concentrations of 0.079 g/L, 0.12 respectively (Figure 3 6) The initial concentration of fluoranthene from Jacksonville (JAX) sample was below detection limit

PAGE 70

70 but increased to 0.059 by end of the leaching event. While the concentration of fluoranth ene leaching out of columns contain in g LC, GN V and MAR reduced to below detection limit (0.0007 1. 2, those of JAX and PEM were still leaching out at 0.059 The leaching of pyrene abated in the LC column after the first leaching event, while columns containing JAX (0.023 (0.010 out measurable amount of pyrene at L/S ratio of 1. 2 (Figure 3 7) Benzo(K)fluoranthene started leaching out of the columns at concentrations ranging from 0.002 0.011 the end of leaching event s ( L/S ratio of 1. 2 ) in columns containing LC and GNV (Figure 3 8) Columns containing JAX, PEM and MAR samples were still leachi ng benzo(k)fluoranthene at very low concentrations ranging from 0.002 at the end of the leaching event Benzo(a)pyrene, which is a chemical of great concern as a result of its potential carcinogenic effect leached out of all the columns (Figure 3 8) The column containing GNV recorded the highest concentration of b enzo(a)pyrene at 0.047 Leaching abated in all the columns except the column containing MAR which leached out benzo(a)pyrene with a concentration of 0.008 at the end of the leaching event. Leaching of benzo(b)fluoranthene was detected in only two out of the five columns containing RAP samples (Figure 3 8) Initial concentrations leached out of the two columns were 0.012 for samples JAX an d PEM respectively By the end of the leaching event (L/S of 1. 2), the concentration of benzo(b)fluoranthene in the PEM sample was below detection limits (0.0001 while that of JAX was 0.005

PAGE 71

71 The measured concentrations of all detected PAH compo unds were below the ir GWCTL s Leaching under saturated condition Polycyclic aromatic hydrocarbons (PAH s ) leached out of all columns containing milled shingles and RAP samples in low concentrations except for RAP sample GNV Analysis of l eachate from GNV di d not reveal any PAH concentrations above detection limits The detected concentrations of leached PAHs were all below GWCTL (Table s A 17 to A 22 ). The PAH concentrations from the saturated condition did not follow a typical leaching curve except for the m illed shingles sample (BRN). Varying concentrations leached out of the RAP samples during initial leaching events (L/S ratio of 0.4) but abated by the second leaching event (L/S ratio of 0.8 ) (Table s A 18 to A 21 ) PAH compound s that did not abate by end o f leaching event did not show any substantial difference s during the entire study (Figure 3 10) The leached concentrations from the RAP samples were all below GWCTLs. In the case of the milled shingles sample BRN, the PAH concentrations followed a typical leaching curve All PAH compounds investigated leached out of BRN except for three compounds (naphthalene, acenaphthylene and chrysene ) The initial concentrations ranged from 0.0036 acenapththene). All the initia l concentrations were below corresponding GWCTLs except for dibenzo(ah)anthracene. Dibenzo(a,h)anthracene from t he first t w o leaching events ( L/S ratio of 0.6 and 1.2) were 1.1 and 1.7 times higher than GWCTL. The concentration however dropped below detect ion limit by the third leaching event (L/S ratio of 1.9) (Figure 3 9). All PAH compound leaching abated by the last leaching event (L/S ratio of 2.5) except for acenaphthene, anthracene, pyrene, and benzo(A)anthracene. While concentrations of

PAGE 72

72 anthracene an d pyrene were 3 order s of magnitude lower than their corresponding GWCTLs, those of acenaphthene and benzo(a)anthracene were 9.5 and 3.7 times lower than corresponding GWCTLs by the last leaching event. Comparison of Results with Published Literature Resu lts in this study were relatively higher than values reported Brandt (Brandt and de Groot, 2001) Brandt conducted dynamic leaching studies on butimen and asphalt samples. One of the five RAP samples investigated in this study leached PAHs in measurable qu antities. This RAP sample (PEM) leached PAHs with measured concentrations which were between 1 to 4 orders of magnitude higher than values reported by Brandt (Table 3 5) Also, m illed aspalt shingles in this study leached PAHs b et ween 2 to 4 orders of mag nitude higher than values reported by Brandt. Legret similarly conducted batch and column leaching studies on RAP samples (Legret et al., 2005) Batch leaching results in this study were comparable to values obtained by Legret For example, Legret report ed ben zo(a)pyrene concentration of 2 0.0 n g/L w hich compares favorably with 23 3 n g/L reported in this study. While phenanthrene in this study was 4.9 times higher than value reported by Legret, fluorene value was 5.4 times lower than the Legret study value Results from the column study conducted under saturated conditions c o mpares favorably with values published by Legret (Legret, et al., 2005) For example, Legret reported a benzo(ghi)perylene concentration of 8 0 n g/L (L/S ratio of 0.5) which compares f avorably with values reported in this study with ranged from 5 0.0 to 9 0.0 n g/L (L/S ratio of 0.4) (Table 3 4) Also, while Legret reported a benzo(a)pyrene concentration of 2 0.0 n g/L (L/S ratio of 0.5) the milled shingles (BRN) in this study leached benzo (a)pyrene with concentration of 26 3 n g/L (L/S ratio of 0.6) (Table 3 4 )

PAGE 73

73 Some PAHs compounds reported in this study were not detect ed in the Legret study. This may be due to lower detection employed in this study compared to the Legret study. This study showed that RAP sampled across Florida did not leach PAHs above Flori d a GWCTLs. Only one out of the five RAP samples leached measurable amounts of PAHs during SPLP leaching test but these values were below GWCTLs. Also, the samples did not leach out PAHs a bove GWCTL under simulated rain conditions. Studies conducted to determine leaching characteristics under saturated conditions did not also show PAH leaching above GWCTL. Based on the leaching characteristics observation for five RAP samples investigated, PAHs are unlikely to leach out of the material when exposed to rain. The use of this waste as base material for road c onstruction and fill material to reclaim pits and borrows may probably not pose environmental health risk. On the other hand, b atch studie s conducted on a single asphalt milled shingles sample using SPLP leaching test showed some PAH compounds leaching above Florida GWCTLs. Column studies conducted to simulate rain conditions on the milled shingles however, did not leach out PAHs above GWCT Ls. Th e SPLP leaching test results suggests that milled shingles could pose environmental risk when used beneficially. Results from the column study, however, shows that e xposure of shingles to rain would not result in leaching of PAHs a bove GWCTL s Only o ne milled shingles sample was investigated in this study hence a generalized leaching characteristics could not be deduced. The storage of milled shingles for use as component in manufacture of new asphalt pavement may probably not pose environmental healt h risk.

PAGE 74

74 A previous study on RAP was inconclusive due to the detection limit employed in the study and also due to downward review of some GWCTLs The detection limit s employed in the previous study were higher than Florida GWCTLs for some of the PAH compo unds investigated. This published result would help regulators take informed decisions on beneficial use of RAP in Florida since groundwater is a major source of drinking water in the State. Since milled shingles was not investigated in the previous study, this data would help regulators take informed decision on this waste stream as well Summary and Conclusion The aim of this study was to address the concerns of PAHs leaching out of a sphalt waste in the event of rainfall. Batch st ud ies using SPLP leaching test revealed low PAH concentration in RAP leachate With the exception of one RAP sample none of the RAP samples investigated leached PAHs above method detection limit s. Also, none of the eight PAHs which leached out of the RAP saple were measured above their corresponding GWCTL s The observation for the milled shingles sample was contrary. The highest PAH concentrations from the batch study were observed in the single milled shingles sample studied Out of the eight PAH compound s detected, two (benzo(a)anthracene and benzo(b)fluoranthene) were 6.5 and 2.1 times higher than their corresponding GWCTL. The b enzo(a)pyrene concentration was 1.2 times lower than its corresponding GWCTL. The c olumn study was designed to mimic piled up a sphalt waste leaching under ag g res s ive rain fall condition s showed measurable amount s of PAHs leaching from the samples. The leaching characteristics for the unsaturated condition followed a typical leaching curve. None of the PAH compounds detected in leac hate from shingles and

PAGE 75

75 RAP column samples under saturated condition were above the ir Florida GWCTL s Six PAH compounds (fluoranthene, pyrene, benzo(k)fluoranthene, benzo(ghi)perylene, benzo(a)pyrene and benzo(b)fluoranthene) leached out of two or more RAP samples. While the detected concentrations of three compounds (benzo(k)fluoranthene, benzo(a)pyrene and benzo(b)fluoranthene) were 2 to 200 times lower than GWCTLs, three other detected compounds (fluoranthene, pyrene and anthracene) were 3 to 4 order of m agnitude lower than the ir GWCTL s In t he case of the milled shingles sample, three PAH compounds which were detected (fluoranthene, pyrene and benzo(ghi)perylene) were 3 order of magnitude lower than their GWCTLs. Also, detected benzo(k)fluoranthene was 90 times lower than corresponding GWCTL. The leaching of PAHs from the RAP samples under saturated condition did not follow typical leaching characteristic s curve s Varying PAH concentrations leached out of the RAP samples during initial leaching events but abated by the second leaching event (L/S ratio of 0.4) PAH compound that did not abate by end of leaching event (L/S ratio of 2.) did not show any substantial differences during the entire study. Leaching of the milled shingles sample under saturated con dition followed a typical leaching curve with the detected PAH s being below GWCTL except for dibenzo(a h)anthracene. The leaching of d ibenzo(a h)anthracene however aba ted by the third leaching event (L/S ratio of 1.9 ) The five RAP samples passed the SPLP test while the milled shingles sample failed. However, PAH concentrations that leached out of the milled shingles under simulated rain condition s were lower than Florida GWCTL s In conclusion, RAP and milled shingles stored under saturated condition or ex posed to rainy weather may

PAGE 76

76 probably not leach PAHs above GWCTLs Unlike the reclaimed asphalt pavement, only one milled shingles sample was studied. Leaching studies on r eprentative milled shingles from across the State of Florida would give a broader pict ure of PAHs leachability from this waste Table 3 2 Accuracy and precision of leached PAHs analysis in column studies using spiked samples Percentage recovery Mean PAH Chemicals BLK JAX RPD (%) Recovery (%) Naphthalene Acenaphthylene Acenapht hene Fluorene Phenanthrene Anthracene Fluorranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 73.2 72.1 71.5 91.7 70.2 99.9 91.4 82.4 100.2 85.9 83.3 79.1 79.9 69.6 56.5 55.2 75.7 82.2 102.0 93.1 83.0 90.4 90.6 71.0 85.2 85.9 79.0 25.8 26.56 19.1 15.7 2.1 1.9 0.7 10.3 5.4 15.9 7.4 7.2 12.7 64.9 63.7 71.5 83.7 76.2 101.0 92.2 82.7 95.3 88.2 77.1 82.1 82.9 74.3 Compounds not investigated in this study.

PAGE 77

77 Table 3 3 Results of SPLP batch leaching test conducted of roadway and storm system samples ( n g/L ) PAH Chemicals BRN PEM LC MAR GNV JAX Detection limit GWCTLs Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo(k)fluoranthene Chrysene Benzo(g,h,i)perylene Benzo(a)pyrene Benzo(a)anthracene Dibenzo(a,h)anthracene Benzo(b)fluoranthene Indeno(1,2,3 cd)pyrene < 80 <3,500 < 14 < 1.6 < 10 735 1 548 1 51 2 67 7 336 5 166 3 324 9 <0. 10 103 5 <80 <3,500 < 14 50 8 < 10 321 0 135 8 6 4 < 0.40 44 2 23 3 34 9 <0. 10 17 0 <80 <3,500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3,500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0. 4 0 <1.1 <0. 3 0 <0 3 0 <0.1 0 <0. 1 0 <80 <3,500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3,500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 80 3500 14 1.6 10 0.70 0.80 0.20 0.40 1.1 0.30 0.30 0.10 0.10 14,000 210,000 20,000 2 80,000 210,000 2,100,000 280,000 210,000 500 4,800 210,000 200 50 5 50 50 Compounds not investigated in this study.

PAGE 78

78 Figure 3 3 Grain size distribution of milled shingles and RAP samples

PAGE 79

79 Table 3 4. Comparison of this study to column study result s in literature Legret (2005) RAP ( n g/L) This study ( n g/L) PAH Chemicals BRN JAX PEM MAR LC GNV L/S Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluorranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benz o (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 5 00 bdl bdl bdl bdl bdl bdl bdl bdl bdl 45 8 0 2 0 bdl 55 25 5 0 0.6 < 80 <3 ,500 662 7 16 6 32 3 48 3 47 4 3 6 <0. 40 70 2 26 3 38 3 5 5 14 7 0.4 < 80 <3 500 < 14 < 1.6 < 10 <0. 70 25 5 1 3 <0. 40 51 6 <0. 30 7 5 <0. 10 5 4 0.4 < 80 <3 ,500 < 14 < 1.6 < 10 6 7 23 7 1 1 <0. 40 83 7 <0. 30 <0. 30 <0. 10 4 2 0.4 < 80 <3 ,500 < 14 <1.6 <10 <0.70 38 2 1 3 <0. 40 30 1 <0. 30 <0. 30 <0. 10 <0. 10 0.4 < 80 <3 ,500 < 14 <1.6 <10 <0.70 24 5 <0.20 <0.40 91 0 <0.3 8 6 < 0 1 0 9 1 0.4 <80 <3,500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 bdl b e low detection limit

PAGE 80

80 Table 3 5 Comparison of this study to batch study results in literature PAH Chemicals Bran dt (2001) Asphalt ( n g/L) Legret (2005) RAP ( n g/L) This study BRN Shingle ( n g/L) PEM RAP ( n g/L) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluorranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)pery lene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene L/S pH Agitation (hrs) 52 1 .0 1 9 2 5 0 3 bdl 0 03 bdl 0 2 0 2 0 2 0 2 0 1 0 2 bdl 10 4 30 bdl bdl bdl 3 0 25 0 3 0 6 0 bdl bdl bdl bdl 2 0 bdl b dl bdl bdl 20 24 735 1 548 1 51 2 67 7 336 5 166 3 324 9 103 5 20 4.2 18 50 8 321 0 135 8 6 4 44 2 23 3 34 9 17 0 20 4.2 18

PAGE 81

81 A B Figure 3 4 Leached PAH concentration v ersus L/S ra t io under unsaturated condition A) fluor anthene B) pyrene

PAGE 82

82 A B Figure 3 5 Leached PAH concentration v ersus L/S ra t io under unsaturated condition A) benzo(k)fluoranthene B) benzo(a)pyrene

PAGE 83

83 A B Figure 3 6 Leached PAH concentration from RAP and shingles v ersus L/S ra t io under unsaturate d condition A) benzo(ghi)perylene from shingles B) fluoranthene from RAP samples

PAGE 84

84 A B Figure 3 7 Leach ed PAH concentration from RAP samples v ersus L/S rat io under unsaturated condition A) pyrene B) benzo(k)fluoranthene

PAGE 85

85 A B Figure 3 8 Leach ed P AH concentration v ersus L/S rat io under unsaturated condition A) benzo(b)fluoranthene B) benzo(a)pyrene

PAGE 86

86 A B Figure 3 9. Leached PAH s from milled shingles (BRN) under saturated condition. A) fluoranthene, pyrene, benzo(b)fluoranthene, and benzo(a)ant hracene B) benzo(k)fluoranthene, benzo(ghi)perylene, benzo(a)pyrene, and dibenzo( ah)anrhracene

PAGE 87

87 A B Figure 3 10 Leached PAHs from RAP samples under saturated condition. A) RAP sample PEM B) RAP sample JAX

PAGE 88

88 CHAPTER 4 POLYCYCLIC AROMATIC HYDROCAR BON DISTRIBUTION IN VARIOUS SIZE FRACTIONS OF ROADWAY S AND STORM SYSTEM R ESIDUALS Introduction Polycyclic aromatic hydrocarbons ( PAH s) in sediments are partitioned between different phases. Investigations to determine the sediment fraction where PAH s are mobilized has turned out varying results. While Wang et al. (2001) reported that PAHs are associated with large size fractions ; Maruya et al. (1996) observed the association of PAHs with fine fractions Simpson et al. (1998) did not observe any correlatio n between PAH concentrations and size fractions Studies conducted on Boston Harbor sediments to ascertain distribution of PAHs in different size fractions revealed PAH s association with large size fractions. The concentration of 16 US EPA priority pollut ant PAHs were analyzed in four size fractions. (<62, 62 125, 125 250, and >250 The highest PAH concentrations were associated with the large size fraction (250 while silt and clay fractions (<62 (Wang, et al., 2001) The observed PAH c oncentration also showed a strong positive correlation with sedimentary organic matter content. A similar study on sediments from Auckland Harbor, New Zealand (Ahrens and Depree, 2004) showed highest PAHs concentration in intermediate grain size fractions (125 250, 250 500, and 500 study was conducted on six size fractions (<63, 63 125, 125 250, 250 500, 5 00 1000, and >1000 Simpson reported a PAH distribution pattern that did not show correlation with grain size (Simpson, et al., 1998) Th e study was conducted on five size fractions (<38, 38 180, 180 300, 300 1180, and >1180 sampled showed PAHs enriched in large particle size fractions, concentrations were similar or exhibited

PAGE 89

89 only slight variation between size fraction s of three other sites. Maruya reported the total PAHs on organic carbon basis (TPAHoc) increased with percentage silt and percentage clay in a study on sediments from San Francisco Bay area (Maruya, et al., 1996) The varying result s of these studies may be due to the varying sources of PAHs in the environment. The question of whether PAHs is present in waste as part of asphalt particles or present as leached PAHs adsorbed to organic coated particles needs to be addressed. This is because different size pa rticle in sediments show different bioavailability (Talley et al., 2002) It would be useful to know what compartment of the waste is associated with PAHs. To address this issue, size fractionation of selected waste (Street sweepings, catch basin sediment stormwater sedi ments, and ditch cleanings) was performed and the PAH associated with each fraction measured. The total organic carbon for the various fractions w as also measured and their correlation with PAH concentration determ ined. Microscopic investi gation was carried out to inspect the samples for asphalt particle. Materials and Methods Sample Collection Two samples each of s treet sweepings, catch basin sediment, stormwater sediments, and ditch cleanings samples w ere collected from various cities ac ross Florida. The assigned codes for the two street sweeping samples were SS 1 and SS 7. The codes for the two catch basin sediment samples were CB 6 and CB 11. The codes assigned to the stormwater sediment samples were SWP 1 and SWP 5. The collected ditch cleaning samples were assigned codes DCL 7 and DCL 8. The sample s w ere collected from each identified sampling site into glass jar s using a stainless steel scoop

PAGE 90

90 and stored below 4 o C in ice chests The l abeled samples were transferred to the laboratory fo r storage below 4 o C prior to analysis. Size S eparation Collected samples w ere homogenized in a steel bowl, air dried to constant weight, and sieved into various size fractions Five size fractions (<75, 75 105, 105 150, 150 212, 212 425, 425 710 m) were generated by wet sieving The <75 particle size fractions were obtained by centrifugation (3000 g, 20 min ). The fractions were dried to a constant weight in an oven at 60 o C. PAH Concentration Determination Sample s ( 2 g) were extracted with 30 mL methylene chloride using an ultrasonic extractor. Prior to the extraction, the sample s were spiked with 10 L benzo(b)chrysene (4 .7 mg/L). The extraction process w as repeated two more times and the co mbined extract concentrated to 5mL using nitrogen blow method. The extract was solvent exchanged to acetonitrile and concentrated to 1 mL using a Kuderna Danish (KD) apparatus. The crude extract was cleaned by employing the use of a C18 cartridge. The cartridge was first loaded with 0.25 g copper powder, cleaned and activated by passing 3mL methanol, followed by 3 mL distilled water. The 1mL crude sample was loaded into cartridge, mixed with 2 mL distilled water and pulled through the column by vacuum. The cartridge was dried 20 minutes under vacuum and PA H eluted with 3 mL of solvent mixture dichloromethane hexane acetonitrile (50:47:3, v : v : v ) The final extract was solvent exchange d to acetonitrile and the sample concentrated to 1mL The analysis of the extracted sample for PAHs chemicals w as conducted by employing the use of a reverse phase high performance chromatography system (Hitachi) equipped with Brownlee Analytical PAH 5um column (Perkin Elmer) and UV

PAGE 91

91 detector. Acetonitrile and water (60:40, v:v) w as used as eluent at 0.7 ml/min in gradient co ndition to 100 % acetonitrile in 60 minutes. This was followed by 60 minutes isocratic condition run. Quantitative determination of PAHs w as achieved by using external standard calibration curve method. Method detection limits, percentage recoveries, and p recision of the method w ere determined. Quality assurance samples included duplicates, spiked samples, and extraction blank. Total Organic Carbon Analysis and Microscopic Studies The total organic carbon of the homogenized fractions w as m easured using a Shimadzu Solid Sample Module (SSM 5000A) for Total Organic Carbon Analyzer (Shumadzu Corporation, Japan) Each size fraction was inspected with a n electron microscope (Carl Zeiss Inc., New York) The focus of the investigation w as to ascertain whether asph alt particles were present in the size fractions of the samples. Results and Discussions Quality Control/Quality Assurance (QA/QC) A q uality a ssurance/ q uality c ontrol (QA/QC) plan involv ed analysis of spikes, duplicates, and blanks Table s A 3 and A 4 sh ow s the precision and accuracy of the analyses of samples. The measured values of PAH concentrations showed g ood precision which was within 20 % in almost all cases with very few exceptions. With the exception of a few compounds the spiked recovery range d between 72 to 10 3 % indicating good accuracy. Total Organic Content Distribution in S ize F ractions Total organic content (TOC) of the fractionated samples are plotted in F igure 4 5 to F igure 4 6 TOC of the two ditch cleaning samples ranged from 0.4 to 1 5.5 % and 2.3 to 18.4 % in the five fractions. The two stormwater sediment TOC values ranged from

PAGE 92

92 1.4 to 6.5 % and 0.7 to 9.7 %, while those of the catch basin sediments ranged from 0.9 to 14 % and 1.4 to 14 %. The street sweeping TOC values in the five fr actions ranged from 1.0 to 15 % and 1.5 to 7. 4 %. With the exception of one ditch cleaning sample (DCL 7), the TOC was highest in the fines size fractions (<75 types. The coarse fraction (75 150 7 recorded the highest TOC. The TOC values measured in the fine fractions of the ditch cleanings were generally higher than corresponding TOC values in street sweeping, stor mwater pond sediments and catch basin sediments. Distribution of PAH in size fractions Concentrations of detected individual PAH compounds and summed PAH s in various size fractions of the sample studied are presented in Tables A 23 and A 24 in A p pendix A and plotted in F igure s 4 1 to 4 4 and F igure s 4 7 to 4 15 The fractionation study was conducted on ditch cleaning samples DCL 7 and DCL 8, stormwater pond sediment s SWP 1 and SWP 5 street sweeping samples SS 1 and SS 7 and catch basin sediment C B 6 and CB 11. The detected individual PAH values varied across fraction size and sample type with values rang ing from 0.005 mg/Kg (anthracene) to 6.1 mg/Kg (benzo(ghi)perylene) The summed PAH compounds also and <212 425 of ditch cleaning sample DCL 7 ( F igure 4 4) This distribution shows a bimodal distribution pattern which suggests two different s ources of PAH (Krein and Schorer, 2000) The possible cause of the bimodal distribution could be due to the fact that coarse fractions originate from abrasion of asphalt of the street while the fine particles originate from combustion and are transported by wind (Krein and Schorer, 2000) Mobilizati in two samples (SWP 1 and CB 6) in this study was

PAGE 93

93 observed in the coarse fractions 75 150 212 ( F igure 4 1 and F igure 4 3 ) Also, t he size fractions <75 150 difference, H in two samples SWP 5 and SS 1 ( F igure 4 1 and F igure 4 2) The fine <75 CB 11, DCL 8 and SS 7 ( F igure 4 2 to F igure 4 4) The individual PAH compounds showed distribution patterns simil ar to the one shown by Normalization of with TOC amplified the difference between the various fractions. Also, mobilization shifted from the fine fraction to the coarse fractions in some cases (Figure 4 7) The PAH compound with highest concentra tions in the size fraction s were benz o(ghi)perylene and indeno(1,2,3 cd)pyrene ( F igure 4 16 to F igure 4 19 ) with highest recorded concentrations being 1.8 mg/Kg and 6.1 mg/Kg respectively. Naphthalene, fluoranthene, chrysene, pyrene and benzo(a)pyrene comp ounds were the next most abundant PAH compounds observed. With the exception of two ring structure naphthalene, which was considerabl y high in four samples (SS 7, CB 11, SWP 1 and SWP 5), all the abundant compounds consisted of 4 and more ring structure s ( py rene, chrysene, fluoranthene ( 4 rings ), benzo(a)pyrene( 5 rings ) and benzo(ghi)perylene, indeno(1,2,3 cd)pyren e (6 rings). Comparison of Results with Published Literature In a study conducted on distribution of PAHs in sediment fractions from Boston Habo r, Wang reported PAH mobilization in the large size fractions (Wang, et al., 2001) The study which was conducted on samples from three sites within the harbor area showed PAHs enrichment in the largest size fraction (>250 of all samples from the sites (Table 4 1) Also, positive correlation between PAHs and TOC was reported Wang suggested pyrogenic sources as possible inputs source of PAHs into the

PAGE 94

94 sediments In another s t u d y, Ahrens reported PAH mobilization in median size fractions (125 250, 250 500, 500 1000 of sediment from Auckland Harbor, New Zealand (Ahrens and Depree, 2004) (Table 4 1) This creek receives storm water from nearby motorway No correlation was observed between PAHs and TOC. Ahrens suggested pyrogenic and petroleum type inputs as being the source of the PAHs. A s tudy conducted by Krein and Marcel on road runoff collected with silk traps and river sediments showed bimodal distribution of PAH (Krein and Schorer, 2000) The three ring detected compounds (fluorine, phenanthrene and anthr acene) were found enriched in t he very fine fractions ( 2 6.3 6.3 12.5 and 12.5 20 ) and the coarse fractions ( 63 200 to 200 630 ). The six ring PAH compound detected (benzo(ghi)perylene, dibenzo(ah)anthracene and indeno(1,2,3 cd)pyrene) were mobilized in the fine <12.5 fraction. In this study, PAHs were found mobilized in varied size fractions. PAHs were found mobilized in fine fractions (<75 ), median size fractions ( 75 150 and 150 212 and bimodally distributed in the fine (75 425 ons. Only 3 out of 8 samples in this study showed strong correlation between PAHs and TOC. This indicates that the source of PAHs in this study was not organic matter which serves as sink for pollutants. PAHs tend to accumulate in organic matter due to int eraction between heterogeneous polymer of organic matter and ar omatic regions of PAHs (Wang, et al., 2001) With the exception of the two streep sweeing samples (SS 1 and SS 7) which showed similar distribution patter n the distribution pattern within the same waste type varied. A similar distribution pattern suggests similar input sources of PAHs.

PAGE 95

95 This study showed that PAHs are mostly mobilized in either the fine fraction or median coarse size fraction of roadway or storm system residuals. A bimodal dist ribution pattern involving the fine and median coarse fractions was also observed This observation suggests variable input sources of PAHs into these wastes waste streams The distribution patterns between individual waste samples were not similar except for stormwater sediments. Correlation between PAH and TOC was observed in only 38 % of the samples studied. Microscopic inspection confirmed presence of asphalt particles in the wastes. Mobilization in fine fractions is likely from pyrogenic sources such a s combustion of fossil fuel which produces soots and gaseous pollutants. These pollutants including PAHs could easily be mobilized by organic matter which serves as sinks for PAHs. Therefore, there is a possibility that waste sample with PAHs mobilized in fine fractions could leach PAHs during rainfall events or pose health risk when ingested. Mobilization of PAHs in the coarse fractions is likely due to abraded road asphalt and this was confirmed by microscopic studies. Exposure to a waste which has PAH m obilized in the coarse fraction is unlikely to pose health ris k s This is because ingestion of such waste is not likely to result in dissolution of the asphaltic particle by gastrointestinal enzymes. Previous PAHs distribution studies have been on soil and sediments from water bodies. This current study therefore contributes new knowledge to PAHs distribution in environmental matrices such as street sweeping and catch basin sediments which have not been reported in literature Seiving of waste to remove f ine fractions before beneficial use is a possible wa y to reduce direct exposure risks to PAHs.

PAGE 96

96 Summary and Conclusion The PAHs were found mobilized in the fine size fractions ( <75 ) and medi um coarse fractions ( 75 150 ) of the street sweeping samples. The PAH m obilization pattern observed for neither the two catch basin samples nor the two stormwater pond sediments were similar While PAH mobilization was observed in 75 150 and 150 212 one stormwater pond sediment and one catch basin sediment, mobilization was observed in <75 150 a second stormwater pond sediment and a second catch basin sediment The observed PAH pattern for one dit ch cleaning sample was bimodal, with highest mobilizations being in the fine size fra ction ( <75 ) and the coarse fraction ( 212 425 ) PAH m obilization in the second ditch cleaning sample on the other hand, was observed in the fine size fraction ( <75 m ) Strong correlations were observed between three of roadway and storm system residuals studied ( F igure 4 20 and F igure 4 21) which suggests that PAH s in these samples are associated with organic matter present in the samples. This observ ed association also suggests that PAH in these samples are from combustion products coming from motor vehicles (Krein and Schorer, 2000) ( 46 ) The other 5 ( F igure s 4 21 to 4 23) probably have their source of PAH being from a bra ded asphalt particles from roadways. Microscopic studies of the fractionated samples confirmed the presence of asphalt particles in the waste streams The mass contribution of the various size fractions to the total dry weight was not investigated in this study. Fut u re work on mass contribution would give a clear picture of the compartment of waste associated with PAH accumulation.

PAGE 97

97 Table 4 1. PAHs distribution in sediments reported in literatu re Wang 2001 Ahrens and Depree 2004 Fractions Fort Poit (mg/Kg) Mystic River (mg/Kg) Island End River (mg/Kg) Fractions (mg/Kg) Motion Creek (mg/Kg) <62 62 125 125 250 >250 8002 7266 12670 54910 9918 9573 16858 38889 59445 127546 113234 358092 <63 63 125 125 250 250 500 500 1000 >1000 4 14.8 24 103.1 67.4 5.2 A B Figure 4 1 Distribution of s ummed PAH in s ize f ractions. A) distribution in sample SWP 5 B) distribution in sample SWP 1

PAGE 98

98 A B Figure 4 2 Distribution of s ummed PAH in s ize f raction s. A) distribution in sample S S 1 B) distribution in sample S S 7

PAGE 99

99 A B Figure 4 3 Distribution of s ummed PAH in s ize f ractions. A) distribution in sample CB 6 B) distribution in sample CB 11

PAGE 100

100 A B Figure 4 4 Distribution of s ummed PAH in s ize f ractions A) distribution in sample DCL 7 B) distribution in sample DCL 8

PAGE 101

101 A B Figure 4 5 Total organic carbon content of A) ditch cleaning samples and B) stormwater pond samples

PAGE 102

102 A B Figure 4 6 Total organic carbon content of A) street sweeping samples and B) catch basin samples

PAGE 103

103 A B C D E F Figure 4 7 Comparison of carbon normalized PAH distribution with non normalized distribution. A) SWP 5 normalized B) SWP 5 unnormalized C) SWP 1 normalized D) SWP 1 unnormalized E) DCL 7 normalized F) DCL 7 unnormalized

PAGE 104

104 A B Figure 4 8 PAH concentrations in ditch cleaning fractions. A) A nthracene in DCL 8 B) P yrene in DCL 8

PAGE 105

105 A B Figure 4 9 PAH concentrations in stornwater pond fractions A) N aphthalene in SWP 5 B) Benzo(a)pyrene in SWP 5

PAGE 106

106 A B Figure 4 10 PAH concentrations in stormwater pond fractions A) Phenanthrene in SWP 5 B) chrysene in SWP 1

PAGE 107

107 A B Figure 4 11 PAH concentrations in street sweeping fractions. A) B enzo(k)fluoranthene in SS 1 B) N aphthalene in SS 7

PAGE 108

108 A B Figure 4 12 PAH concentrations in street sweeping. A) Phenanthrene in SS 7 B) Benzo(a)pyrene in SS 7

PAGE 109

109 A B Figure 4 13 PAH concentrations in catch basin fractions. A) P henanthrene in CB 6 B) P yrene in CB 6

PAGE 110

110 A B Figure 4 1 4 PAH concentrations in catch bas in fractions. A) B enzo(k)fluoranthene in CB 6 B) A nthracene in CB 11

PAGE 111

111 A B Figure 4 1 5 PAH concentrations in catch basin fractions A) F luoranthene in CB 11 B) B enzo(a)pyrene in CB 11

PAGE 112

112 A B Figure 4 1 6 Relative enrichment of individual PAHs storm water pond sediment fractions A) sample SWP 1 B) sample SWP 5

PAGE 113

113 A B Figure 4 1 7 Relative enrichment of individual PAHs ditch cleaning sediment fractions. A) sample DCL 7 B) sample DCL 8

PAGE 114

114 A B Figure 4 1 8 Relative enrichment of individual PAHs catch ba sin sediment fractions. A) sample CB 6 B) sample CB 11

PAGE 115

115 A B Figure 4 1 9 Relative enrichment of individual PAHs in street sweeping fractions. A) sample S S 1 B) sample S S 7

PAGE 116

116 A B Figure 4 20 Correlation between total PAH (mg/Kg) and total organic carbo n (%) in various samples A) sample CB 6 B) sample S S 7

PAGE 117

117 A B Figure 4 21 Correlation between total PAH (mg/Kg) and total organic carbon (%) in various samples. A) sample DCL 8 B) sample CB 11

PAGE 118

118 A B Figure 4 22 Correlation between total PAH (mg/ Kg) and total organic carbon (%) in various samples. A) sample DCL 7 B) sample SWP 5

PAGE 119

119 A B Figure 4 23 Correlation between total PAH (mg/Kg) and total organic carbon (%) in various samples. A) sample SWP 1 B) sample SS 1

PAGE 120

120 CHAPTER 5 BIOACCESSIBILITY OF P OLYCYCLIC AROMATIC H YDROCARBONS IN ROADW AY AND STORM SYSTEM RES IDUE USING IN VITRO GASTROINTESTINAL LEA CHING TEST Introduction Regulatory cleanup target levels for solid waste are set based on risk assessments. These assessments rely on the estimated ora l toxicity of the substance. Toxicity values are usually generated from animal or human studies (Rubyet al., 1999) Oral toxicity is determined on the basis of studies in which a pollutant is dissolved in food or water. If these toxicity values are used in risk assessment of a pollutant in solid waste, the impact of the pollutant in the waste may be over estimated since a hundred percent of pollutant is assumed to be accessible. For example, ingestion of a piece of reclaimed asphalt product (RAP) is likely not to result in hundred percent bioaccessibility of PAHs in waste ; therefore, there is the need to determine the exact fraction accessible. Bioavailability studies have been conducted in the past via in vi vo studies on laboratory animals. In vitro tests p rovide a rapid and inexpensive alternative for researchers. Oral bioavailability is the fraction of an administered dose that reaches the central (blood) compartment from the gastrointestinal tract (Ruby, et al., 1999) Oral b ioaccessibility of a substance is the fraction that is soluble in the gastrointestinal environment and is available for absorption (Ruby, et al., 1999) Various researchers have developed in vitro leaching tests for hydrophobic organic compounds which includes PAH (Table 5 1 ) (Hack an d Selenka, 1996; Oomen et al., 1999; Holman, 2000; Wittsiepe et al., 2001; Ruby et al., 2002a) All these tests have the following important components: pH condition, leaching time, gastric leaching, and intestinal

PAGE 121

121 leaching. The pH of an empty stomach i s between 1.5 and 2.5 (Mercier et al., 2002) The pH increases gradually in the intestine to neutral or basic due to the production of bicarbonates and other agents by the pancreas (Ruby et al., 2002b) Another critical factor is the residence time in th e gastric tract and the intestine. The gastric contents are emptied completely into the small intestine within approximately 2 hours in humans. is empties in 54 68 min utes (Ruby et al., 1996) This informed the selection of 1hour for ga stric leaching since children are more likely to ingest contaminants because of their hand to mouth activities. Approximately 3 5 hours is required for passage of chyme (semifluid digested food material) from the top of the small intestine to the entrance of the large intestine in adults (Ruby, et al., 1996) The solid to fluid ratio is arbitrary selected since there is insufficient data to support this. Also, t he digestive enzyme selection and concentration varies from one researcher to another. This is du e to the fact that concentrations are highly variable in the human system. Investigation of oral bioaccessibility dioxins/furans in soils from Midland, Michigan, by Ruby et al. (2002b) revealed that, 2,3,7,8 tetrachlorodibenzo p dioxin (TCDD) bioaccessi bility ranged from 15 to 48% with an average of 27% In vivo estimate of TCDD bioavailability from soil yielded an average of 35%. This similarity suggests that the in vitro test developed by Ruby et al (2002b) produces values in the same range as histori c animal studies The impact of a pollutant in wastes may be over estimated due to hundred percent bioavailability assumptions in risk assessment s To address this issue, i n vitro studies were conducted on street sweepings, stormwater pond sediments, catch basin sediments, and ditch cleaning using method developed by Ruby et al.

PAGE 122

122 (2002b) Results would provide an insight into the exact amount of PAHs bioaccessible when these waste are ingested Table 5 1 Comparison of In Vitro Extraction Tests for hydroph obic organic compounds in Soil (Ruby, et al., 2002b) Test parameters Hack and Selenka ( 1996 ) Holman ( 2000 ) Oomen et al ( 2000 ) Wittsiepe et al ( 2001 ) Ruby et al ., ( 2002 ) Compound Soil size fraction Soil/solution ratio Gastric pH Gastric enzymes/ o ther substances Gastric time (hrs) Intestinal pH Intestinal enzymes/other substances Intestinal time(hrs) PCBs, PAHs 1:120 2.0 Pepsin/ Nacl, mucin, milk 2 7.0 Trypsin Pancreatin/ bile 6 PAH < 1mm 1 :50 N/A N/A N/A 6.5 Bile salt, lipid 4 PCBs, 1:65 1.0 Pepsin, BSA mucin, urea 2 5.5 pancreatin/ bile 2 PCDDs /Fs <100, 100 1:60 Pepsin/ Nacl, BSA, glucose, urea, milk, 3 7.5 pancreatin/ bile 3 PCDDs/Fs < 250 m 1:100 Pepsin / glycine, Nacl, BSA Mucin, oleic acid oil 1 7.2 pancreatin/ bile 4 Materials and Methods Sample Collection Two samples each of s treet sweepings, catch basin sediment, stormwater sediments, and ditch cleanings samples w ere collected across Florida a nd stored below 4 o C prior to transfer to the laboratory for the experiment.

PAGE 123

123 In Vitro Gastrointestinal Leaching Test This experiment combines extraction fluid composition and experimental condition reported by Ruby et al. (2002b) and a modified experimental setup reported by Hack and Selenka (Hack and Selenka, 1996) The in vitro gastrointestinal leaching test consists of several steps The process include d a sample preparation step where the sample s w ere dried and sieved into desired fraction (<250 Next is the solution preparation step where leaching solution is designed to mimic condition in the gastric and intestine tracts. The extraction step involves a leaching process designed to mimic the mixing mechanism in the stomach The resulting leac hate w as solvent extracted and analyzed for PAH and bioavailable fraction determined. Sample preparation The sample s w ere homogenized in stainless steel bowl s and air dried. This w as followed by sieving portion of samples into fine (<250 m) fractions. This is the fraction which is most likely to adhere to human hands and become ingested during hand to mouth activity (Ruby, et al., 2002b) Gastrointestinal leaching test w as performed on the sieved fine fraction Leaching solution preparation and leaching te st Gastrointestinal leaching fluid w as prepared by adding 15.02 g of gycine (Sigma Aldrich Bellefonte PA ) to 1 L deionized water. The pH w as adjusted to 1.5 with concentrated HCl. To this solution was added 8.8g sodium chloride, 1.0 g of pepsin, 5 g of b ovine serum albumin (BSA) and 2.5 g of mucine (Sigma Aldrich Bellefonte PA ) The gastrointestinal solution ( 600 mL) w as placed in a 1L amber glass bottle and 3 .6 mL oleic acid (Sigma Aldrich Bellefonte PA ) added. Six gram s of the sample w as added to the resulting solution and the glass bottle containing the gastrointestinal

PAGE 124

124 solution purged with nitrogen in an anaerobic chamber The sealed bottle was shaken for 1 hour at 37 o C using an I 2400 incubator shaker (New Brunswick scientific Edison NJ ) to simulat e the gastric tract phase digestion. The next stage w as the intestinal phase extraction which involve d adjusting the pH to 7.2 0.2 using sodium hydroxide (50% w/w). P orcine pancreatine (3 6 0mg) and bovine (2 .4 g) (Sigma Aldrich, Bellefonte, PA) w ere added to the solution purge d with nitrogen and shaken for 4 hours using incubator shaker at 37 o C The extract w as decanted and centrifuged at 7 000g for 10 minutes (Hack and Selenka, 1996; Ruby, et al., 2002b) The supernatant w as extracted using hexane/acetone (3:1) mixture ( Hack and Selenka, 1996) PAH extraction from gastrointestinal solution The next step after the gastrointestinal leaching test was to determine how much PAHs leached into the solution. This was accomplished by extracting leachate with an or ganic solvent and cleaning the extract to remove other chemicals that would cause interference. The gastrointestinal extract (500mL) was measured into a separatory funnel followed by addition of 1mL benzo(b)chrysene surrogate ( g/L) standard. Ten grams NaCl and 80mL hexane/acetone (3:1) solvent mixture was added and shaken for 2 minutes. The organic layer was separated after 3 hours, with formed emulsion phased separated by centrifugation at 7000g for 10min. The e xtraction s tep w as repeated two more times using 60mL hexane The separated organic layer was combined and dried over 60g sodium sulfate (Fisher Sceintific Pittsburgh, PA ) The extract was concentrated to 0. 5mL using nitrogen Turbo Vap II Concentration Workstation ( Zymark Corporation) and re dissolved in 4.5mL of methylene chloride

PAGE 125

125 The next process involved the use of two different cleaning procedures to isolate the desired analyte from the crude extract. The crude extract was cleaned using two cleaning steps. The first step was the use of gel permeation cleanup (GPC) technique (USEPA Method 3640b) to separate the PAHs from undesired compounds. The procedure involved filling a glass chromatography column (600 mm X 25 mm ID) with slurry prepared by mixing bio beads (200 400 mesh, Bio Rad Laboratory Hercules, CA ) with methylene chloride. The prepared gel permeation column (GPC) was connected to the HPLC unit and the retention time composite 16 PAH peak identified using the PAH standards (Ultra Scientific, Kingston, R I ). The cleaned samples fraction corresponding to the retention time of the composite 16 PAHs was collected and concentrated to 5mL. This extract was solvent exchanged to acetonitrile, concentrated to 1mL and further cleaned using C18 cartridge. The C18 cl eaning step involved conditioning of the cartridge with 3mL methanol by drawing it through the column under vacuum. This was followed by passing 3 mL deionized water through it. Crude sample ( 1 mL) was mixed with 2 mL deionized water in the column reservoir a nd mixture pulled through C18 SPE column by vacuum. The air dried column was eluted with 6mL of solvent mixture (dichloromethane h exane acetonitrile, 50:47:3 v: v). The collected sample was solvent exchange to acetonitrile and made up to 1mL prior to an alysis with HPLC. Sample Analysis The extract from the in vitro study was analyzed using a high performance chromatography system (Hitachi) equipped with Brownlee Analytical PAH 5um column (Perkin Elmer), Fluorescence and UV detectors. Acetonitrile and w ater (60:40, v:v) was used as eluent at 0.7 ml/min (in gradient condition). Quantitative determination of PAHs w as achieved using external standard calibration curve method. Method detection limits,

PAGE 126

126 percentage recoveries, and precision of the method were de termined. Quality a ssurance procedure involved including one extraction blank, a duplicate sample, and a spiked sample in every analytical batch consisting of 20 samples. Results and Discussions Quality Control/Quality Assurance (QA/QC) The q uality a ssura nce/ q uality c ontrol (QA/QC) plan involv ed analysis of spikes, duplicates, and blanks samples. Table s A 6 and A 8 show the precision and accuracy of the analyses of samples. The measured values of PAH concentrations showed good precision which was within + 20% in almost all cases with very few exceptions. With the exception of few compounds, the spiked recovery ranged between 7 0 to 78 % indicating good accuracy. Results of gastrointestinal leaching test conducted on two catch basin samples (CB 6 and CB 11) t wo ditch cleaning samples (DCL 7 and DCL 8) one each of storm water pond (SWP 5) and street sweeping samples (SS 7) is presented in table 5 2 and plotted in figure 5 1 Bioaccessibility values varied across the studied samples For example, varying result s were obtained for the catch basin samples. While bioaccessibility for the detected PAHs in sample CB 11 ranged from 1.0 to 3.2%, that of CB 6 ranged from 15.8 to 78.7%. The mean for the samples CB 11 and CB 6 were 1.7% and 43.0% respectively. Bioaccessib ility values of five PAH compounds (Benzo(a)Pyrene, Benzo(a)ant h rac ene, d ibenzo (a,h) anthrace n e, Benzo(a) f louranthene, and indeno(1,2,3 cd)pyrene) found in DCL 11 were less than 2% ( Table 5 2 ) For the second catch basin sediment sample studied (CB 6), the bioaccessibility values obtained were between 7 to 12 times higher than catch basin sample CB 11.

PAGE 127

127 Bioaccessibility results for ditch cleaning samples ranged from 10.6 to 47.6% for DCL 7 w hile those of DCL 8 ranged from 9.8 to 37.5%. The mean values wer e 23.5% and 20.0% for DCL 7 and DCL 8 respectively. Benzo(a) p yrene which is a PAH of much concern, recorded a bioaccessibility of 10.9% in DCL 8. The mobilization in gastrointestinal solution of DCL 7 was 2 times higher. On the other hand, t he bioaccessib ility of b enzo(a)anthracene (13.2%) in DCL 8 was 1.3 times lower than value recorded for DCL 7 (17.3%). Test results obtained for the storm water pond sediment samples were lower than all the ditch cleaning and catch basin samples except for CB 6. Bioacces sibility results ranged between 6.7 to 17.2% with a mean value of 11.0%. The benzo(a) p yrene bioaccessibility value obtained for SWP 5 in this study was 6.8%. Street sweeping (SS 7) study results ranged from 28.1 to 80.5% and had a mean of 49.8%. The mean b ioaccessibility value of the street sweeping (SS 7) was the highest observed, and was followed by catch basin sample CB 6. The second catch basin sample (CB 11) had the lowest bioaccessibility value (1.7%). The two ditch cleaning samples had very close bio accessibility values (23.5 and 20%). Comparison of R esults w ith P ublished I n V itro and I n V ivo S tudies Hack and Selenka (1996) studied mobilization of PAH from contaminated soil using digestive tract model. Bioaccessibility of PAH in contaminated soil, se wage sludge, and street asphalt were 23, 66 and 35% respectively (Table 5 3 ) Another in vitro study conducted by Pu on four soils contaminated with phenanthrene yielded bioavailability values ranging from 17 to 69.8% (soil contaminated with 200mg/Kg phena nthrene) and 55 to 88% (soil contaminated with 400mg/Kg phenanthrene) (Puet al., 2004) (Table 5 4 ) Ditch cleaning bioaccessibility results in this study are comparable to results obtained from a contaminated soil study conducted by Hack and

PAGE 128

128 Selenka ( 1996) ( T able 5 3) The s tormwater bioaccessibility value was two times lower than results obtained by the Hack and Selenka (1996) study Comparing the street sweeping and catch basin results from this study to street asphalt study results obtained by Hack and S elenka (1996) value s obtained in this study were 1.2 and 1.4 times higher (Table 5 3) In vivo studies to determine bioavailability of ingested PAHs using animals such as mice and rats have been reported (Gron, et al., 2007) Phenanthrene bioavailabilit y studies conducted by Gron et al. (2007) yielded results ranging from 14.9% to 48.6% (T able 5 5) Bioaccessibility v alues obtained for phenanthrene in this study ranged from 3.2% to 64.4% ( T able 5 2). With the exception of SS 7 which recorded a bioaccessi bility of 64.4%, results obtained were all less than 38%. Relative bioavailability of Benzo(a)Pyrene obtained by in vi vo studies using mice and contaminated soil yielded results ranging from 7.3 to 31% (T able 5 6) Benzo(a)pyrene r esults from this study r anged from 1.0 to 50.6%. With the exception of two samples (SS 7 and CB 11), the values obtained in this study fall within ranged published by Gron (Gron, et al., 2007) (T able s 5 2 and 5 6 ). Results from this study showed that bioaccessibility of total PAH s from roadway and storm system residuals ranged from 1.7 to 49.2%. Though PAHs are present in these wastes, amount available if ingested is lower that estimated value of 100% used in the development of SCTLs. For example, the fraction of benzo(a)pyrene ac cessible from catch basin sample CB 11 is 1.02% compared to the 100% assumed. To futher explain this point, a simplified version of the equation employed in developing SCTLs for carcinogens shown below was used cla r ify this point.

PAGE 129

129 W here SCTL = Soil cleanup target level, TR = target cancer risk (unitless), BW = body weight (Kg), AT = average time (days), ED = exposure duration, IR o = oral ingestion rate CSF o Cancer slope factor (mg/Kg day) 1 FC fraction from contaminated sou rce. The residential SCTL for benzo(a)pyrene is 0.1mg/Kg. The fraction from source (FC) was assumed to be 1. Holding all parameters constant and r eplacing fraction from source (FC) in the above equation by 0.0102 (1.02%) changes the SCTL dramatically from 0.1 to 9.8mg/Kg. This change is almost 2 orders of magnitude increment in the SCTL. Hence, wastes such as street sweeping, catch basin sediment, ditch cleaning, and stormwater pond sediments are over conservatively limited in their potential beneficia l use s. Summary and Conclusion Bioaccessibility results from this study showed that bioaccessibility of total PAHs from roadway and storm system residuals ranged from 1.7 to 49.2 %. The highest summed PAH bioaccessibility values (49.2 and 40.6 %) were observe d in one catch basin sediment and one street sweeping sample. A second catch basin sample recorded the lowest bioaccessibility value (1.2%). Fractionation studies conducted on three of the samples investigated con centration Bioaccessibility values of two of these samples were relatively higher ( F igure 5 1 ). This may be due to the fact that PAH was bound to organic matter and was easily partitioned into the gastrointestinal leaching fluid. However, result observed in one of the samples which showed correlation was relatively lower. Th ree other samples investigated did not show correlation between

PAGE 130

130 Figures 4 21 and 4 22 ). Also, the PAHs were found mobilized in the fraction and medium coarse (75 of these waste One d and coarse 212 These observations support low bioaccessibility values for two of these waste which did not show correlation and TOC This could observation could be due to the fact that PAHs mobilized in the coarse fractions of these samples may be present as components of asphalt particle. Dissolution of an asphalt particle could possibly be more difficult compared to the fin e size fractions with high organic content and larger surface area. The fractionation result does not, however, explain low bioac cessibility value of one of these samples This may be due to other factors not investigated in this study, eg. mass contributi on of the various fractions to the total dry weight. Results from this study compares favorable to values obtained by the Hack investigation (Hack and Selenka, 1996) In the development of SCTL, h undrend percent was assumed as fraction of pollutant from s ource. The use of these bioaccessiblity values in place of the one hundred percent assumed would yield higher SCTL values thereby supporting the assertion that beneficial use of these waste s may be less risky than indicated by risk assessment using curren t protocol. Future studies on bioaccessibility of PAHs found in reclained asphalt pavement would enhance understanding these pollutants in roadway and storm system samples.

PAGE 131

131 Table 5 2. Results of in vitro studies conducted of roadways and storm syst em samples Bioaccessibility of PAHs in six solid waste samples PAH Chemicals CB 11 (%) CB 6 (%) DCL 7 (%) DCL 8 (%) SWP 5 (%) SS 7 (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene C hrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 1.4 3.2 1.4 2.3 2.1 1.7 1.9 1.6 1.0 1.6 1.5 1.4 1.1 1.7 26.8 50.9 50.2 51.8 40.7 42.6 15.8 37.0 35.3 78 .7 40.6 25.8 38.4 28.6 10.6 47.6 20.9 11.7 21. 6 17.3 12.2 22. 8 37.5 23.0 30.0 16.5 37.1 9.8 13.3 10.9 13.2 12.1 16.3 16.0 6.9 8.6 9.7 12.9 15.1 10.3 9.7 6.8 13.3 10.3 17.1 10.4 64.4 28.1 51.1 55.8 43.8 52.9 45.5 50.6 30.1 44.7 80.5 49 2 CB 6 and CB 11 catch basin samples, DCL 7 and DCL 8 ditch cleaning samples, SWP 5 stormwater pond sample, and SS 7 street sweeping sample Figure 5 1 Mobilization of PAHs in the in vitro extraction fluid of various samples

PAGE 132

132 Table 5 3 PAH mobilization from polluted soil, sewage sludge, shredded metal scrap, blast sand and street asphalt by means of gastro intestinal model (Hack and Selenka, 1996) Contaminated material PAH mobilized (%) Soil Sewage sludge Shredded scrap metal Blast sand S treet asphalt 23 66 51 56 35 Table 5 4 Percent of phenanthrene mobilized from soils using in vitro extraction (Pu, et al., 2004) Soils Phenanthrene mobilization (%) Bloomfield Milford Toronto Heiden 69.8 22.4 58.6 17.7 Table 5 5 Bioavailability o f soil sorbed phenanthrene in rats treated with 400 g/Kg bw (Pu, et al., 2004) Spiked soils samples Absolute bioavailability (%) Bloomfield Milford Toronto Heiden 48.6 16.3 20.8 14.9 Table 5 6 Properties of soils with benzo(a)pyrene relative bioavaila bility data from mice (Gron, et al., 2007) Soil number Concentration (mg/Kg bw) Relative bioavailability (%) 1 2 3 48 50 5.6 7.3 9.9 31

PAGE 133

133 CHAPTER 6 SUMMARY CONCLUSIONS AND RECOMMENDATION FOR FUTURE WORK Summary of Major Observations The purpose of this research was to investigate the impact of PAHs on beneficial use of waste materials. A summary of major observations from this research are as follow: Benzo(a)pyrene in three waste types (ditch cleaning, stormwater pond sediment s and catch basin sediments ) were 2.6 to 50 times lower than the residential SCTL and 17.9 to 350 times lower than the industrial SCTL. Benzo(a)pyrene in street sweepings was 1.2 times higher than residential SCTL but 6 times lower than industrial SCTL. With t he exception of street sweepings none of the detected PAH compounds exceeded the GWCTLs. Two street sweeping samples leached benzo(b)fluoranthene above GWCTL. One out of the two samples leached benzo(a)pyrene above the GWCTL as well. G eometric means were one order of magnitude lower than the GWCTLs. With the exception of one sample PEM, none of the five RAP samples studied leached PAHs above method detection limit under batch leaching tests None of the 8 PAHs which leached out of the one sample were measured above their corresp onding GWCTL. In the case of milled shingles sample, two out of eight detected PAH compounds (benzo(a)anthracene and benzo(b)fluoranthene) were 6.5 and 2.1 times higher than their corresponding GWCTL. Benzo(a)pyrene concentration was 1.2 times lower than i ts corresponding GWCTL. Results from column tests found that n one of the PAH compounds detected in leachate from RAP and shingles samples under unsaturated condition s were above the Florida GWCTL. Under saturated condition s dibenzo(ah)anthracene leached out of shingles above the Florida GWCTL but abated by a solid to liquid ratio of 1.9 Fractionation study results on two each of ditch cleanings, street sweepings, catch basin sediments, and stormwater pond sediments showed varied mobilization patterns. A b imodal distribution pattern was observed for one ditch cleaning catch basin sediment s and ditch cleanin gs. While PAHs were observed mobilized size fractions of the two street sweepings and one stormwater pond sediment sample mobilization in a second stormwater pond sediment sample and a catch basin sediments samples were observ ed in the 75

PAGE 134

134 Strong correlations were observed three of the samples investigated Results from this study showed that bioaccessibility of total PAHs from roadway and storm system residuals ranged from 1.7 to 49.2 %. The highest summed PAH bioaccessibility values (49.2 and 40.6 %) were observed in one catch basin sediment and one street sweeping sample. A second catch basin sample recorded the lowest bioaccessibility value ( 1.2% ) Interpretation a nd Implication In order for roadway and storm system residual s to be used beneficially in Florida, risk assessment is required. This risk assessment involves comparing concentrations of regulated pollutants including PAHs with Florida SCTLs. Exceeding poll utant concentration suggests a direct exposure risk. Also, to assess whether waste could leach pollutants into groundwater, leached pollutant concentrations are compared with Florida GWCTLs. Results of studies conducted on 10 samples each of ditch cleaning s, stormwater pond sediments, and catch basin sediments showed that geometric mean concentration of PAHs in these wastes were lower than Florida residential and industrial SCTLs. This observation suggests that these waste pose minimal PAH direct exposure r isk based on risk assessment using the 10 samples collected across Florida The use of these wastes under residential settings may likely not pose direct exposure risk as the geometric mean concentrations of PAHs are below the SCTLs. Contrary to this, the geometric mean of benzo(a)pyrene detected in 10 street sweepings samples was slightly higher than the residential SCTL. This outcome suggests a possible direct exposure risk if used beneficially in residential areas. Leached PAHs from all wastes studied we re lower than corresponding GWCTLs. This outcome suggests that these wastes investigated pose minimal risk of leaching PAHs i nto groundwater since leached PAH concentrations were lower than Florida GWCTLs Since the results obtained for

PAGE 135

135 benzo(a)pyrene in street sweepings was relatively close to the SCTL, it behooves that other factors considered in the development of SCTL be investigated to better assess potential risk. One good example is the fraction of pollutant bioaaccessible This is assumed to be one hundred percent in the SCTL. B ioaccessibility PAH in roadway and storm system samples investigated were observed to be between 1.7 % to 49 %. The low end values may probably be due to PAHs being present as components of coarse fraction of waste and being inaccessible. Dissolution of coarse size particle could possibly be more difficult compared to the fine size fractions which have high organic matter content and larger surface area. The use of these bioaccessiblity values in place of the one hundred perc ent assumed would yield higher SCTL values, thereby supporting the assertion that beneficial use of these wastes may be less risky than indicated by risk assessment using current protocol To better undersand the source of the observed PAH concentrations, fractionation studies were conducted on the waste. PAH mobilization in the roadway and storm system fraction as well as the coarse 75 212, and 212 possible source of PAHs in the coa rse fractions is abraded asphalt particles from roadways. The source of PAHs in the fine fraction is probably from particles emitted from combustion engines in motor vehicles. The observation strenghthens the assertion that PAHs observed in some of these w aste may be from abraded asphalt road material. Results from leaching characteristic studies on five RAP samples showed that these waste pose minimal potential risk of leaching PAHs into ground water based on

PAGE 136

136 risk assessment using Florida GWCTLs Contrary to this observation, the single milled asphalt shingles sample studied was found to pose risk of leaching PAHs into groundwater. Unlike the reclaimed asphalt pavement, only one milled shingles sample was studied. Leaching studies on reprentative milled sh ingles from across the State of Florida would give a broader picture of PAHs leachability from this waste Column studies designed to mimic exposure of asphalt waste to rain does no support th e observation of milled shingles leaching into groundwater. Rec ommendations for Future Work Unlike the reclaimed asphalt pavement, only one milled shingles sample was studied. Leaching s tudies on r eprentative milled shingles from across the State of Florida would give a broader picture of PAHs leachability from this w aste This was focused on 10 samples of each street sweepings, catch basin sediments, stormwater sediments, and ditch cleanings. Future work involving a larger sample size of these waste streams across the state of Florida would give results which would be more representative of the extent of PAH contamination across the State. To confirm that PAHs are present as components of asphalt particles in large size fractions i n vitro studies needs to be conducted on size fractionated portions of these waste strea m. Also, studies on bioaccessibility of PAHs found in reclained asphalt pavement would enhance understanding these pollutants in roadway and storm system samples. The mass contribution of the various size fractions to the total dry weight was not investiga ted in this study. Future work on mass contribution would give a clear picture of the compartment of waste associated with PAH accumulation.

PAGE 137

137 APPENDIX A SUPPLEMENTARY TABLES Table A 1 Accuracy of total PAHs analysis using spiked samples Spike r ecover y (%) Mean PAH Chemicals CB 10 CB 10 Dup r e c overy (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluorranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h ) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 69.1 68.0 67.7 81.8 78.4 75.3 112.4 88.4 73.1 91.2 73.1 76.5 63.1 69.7 62.8 87.4 75.8 62.9 68.7 71.5 67.3 74.9 122.0 87.3 74.0 117.8 81.7 85.6 62.1 75.1 79.2 110.0 72.4 65.4 68.2 76.6 72.8 75.1 1 17.2 87.9 73.6 104.5 77.4 81.0 62.6 72.4 71.0 98.7 Table A 2 Accuracy and precision of batch leached PAHs analysis using spiked street sweping samples Leached concentration ( g/L) RPD PAH Chemicals SS 9 SS 9 Dup (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluorranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene B enzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 5.8 1.2 0.20 0.96 0.97 0.42 0.19 0.67 0.28 0.12 5.7 1.3 0.27 0.84 0.63 0.38 0.19 0.75 0.14 1.9 8.9 29.9 13.5 43.0 10.9 1.1 12.1 14.4 Compounds not investigated in this study.

PAGE 138

138 Tab le A 3 Accuracy of total PAHs analysis in fractionation studies using spiked fractionated samples Spike recovery Mean PAH Chemicals CB 6 (%) SWP 1 (%) r ecovery (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluorranth ene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 68.2 84.9 71.1 81.4 78.4 93.2 98.1 88.2 73.1 76.9 99.5 76.2 76.0 69.4 95.0 87.1 6 4.5 61.3 53.5 71.2 67.3 91.3 107.7 87.1 74.0 90.7 81.3 85.2 57.8 74.8 79.2 109.6 66.3 73.1 62.3 76.3 72.8 92.3 102.9 87.7 73.6 83.8 90.4 80.7 66.9 72.1 87.1 98.3 Table A 4 Precision in fractionation study analysis using fractionated dich cleaning sampl e (212 425 m) PAH c oncentration s (mg/Kg) PAH Chemicals DCL 8 DCL 8 Dup RPD (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluorranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 1.23 0.036 0.003 0.068 0.095 0.076 0.27 0.062 0.016 0.077 0.023 0.082 0.85 0.040 0.005 0.060 0.084 0.060 0.23 0.052 0.018 0.052 0.019 0.045 36.2 11.9 35.1 12 .1 12.4 22.5 14.6 18.0 8.0 39.4 20.3 57.7

PAGE 139

139 Table A 5 Precision in fractionation study analysis using fractionated stormwater pond s amples (212 425 m) PAH c oncentration s (mg/Kg) PAH Chemicals SWP 4 SWP 4 Dup RP D (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluorranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthrace ne Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 0.21 0.11 0.01 0.15 0.28 0.02 0.20 0.52 0.17 0.10 0.16 0.2763 0.10 0.02 0.29 0.35 0.03 0.26 0.64 0.21 0.14 0.1 7 26.2 7.7 70.6 65.9 23.5 60.7 22.8 20.4 23.4 32.9 9.3 Table A 6 Accuracy of PAHs analysis in in vitro studies using spiked samples Recovery MDL PAH Chemicals (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluorranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 60.1 64.8 66.5 70.2 78.3 72.1 67.2 72.8 70.9 79.2 61.8 73.1 85.6 69.3 71.6 70.5 2.5 2.5 4.9 0.5 0.2 0.1 0.2 0.5 0.1 0.2 0.4 0.2 0.2 1.0 0.1 0.2

PAGE 140

140 Table A 7 Precision in in vitro study analysis using duplicate stormwater pond samples Bioac essibility PAH Chemicals SWP 5 B (%) SWP 5 C (%) RPD (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluor anthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a, h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 6.8 9.0 10.4 15.9 15.1 11.8 4.2 12.5 8.9 22.2 7.0 8.2 8.9 9.9 8.9 9.7 9.3 14.2 11.6 12.0 1.7 4.9 7.7 23.1 14.1 37.8 6.1 13.5 29.8 Table A 8 Precision in in vitro study analys is using duplicate dich cleaning samples Bioacessibility PAH Chemicals DCL 8B (%) DCL C (%) RPD (%) Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluor anthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Ben zo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene 39.7 17.8 33.0 20.5 10.8 11.6 12.3 5.1 8.9 12.9 15.8 35.3 28.2 27.0 12.5 63.4 8.1 14.3 16.8 17.5 11.4 16. 8 6 22.5 9.9 24.1 70.8 17.8 7.4 53.2 32.4 6.4 2.8

PAGE 141

141 Table A 9 Concentrations of PAHs in leachate from column containing BRN (ng/L) Leaching events Day 1 Day 2 Day 5 Day 8 Day 13 Day 18 Day 32 L/S (L/Kg) 0.06 0.12 0.31 0.50 0.81 1.12 1.99 PAH Chemicals Naphthalene Acenapht hylene Acenaphthene Fluorene Phenanthrene Anthracene Fluor anthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1 .6 <10 230.8 85.8 5.5 <0.40 <1.1 17.3 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 218.7 38.8 2.1 <0.40 <1.1 5.9 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 286.7 67.6 5.2 <0.40 <1.1 12.5 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 253.5 43.6 3.8 <0.40 < 1.1 11.7 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 130.9 17.6 3.9 <0.40 <1.1 11.9 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 158.6 30.1 3.2 <0.40 <1.1 <0.30 <0.30 <0.10 <0 .10 Compounds not investigated in this study.

PAGE 142

142 Table A 10 Concentrations of PAHs in leachate from column containing BRN duplicate (ng/L) Leaching events Day 1 Day 2 Day 5 Day 8 Day 13 Day 18 Day 32 L/S (L/Kg) 0.06 0.12 0.31 0.50 0.81 1. 12 1.99 PAH Chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluor anthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluor anthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 154.8 63.7 3.9 <0.40 22.9 11.7 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 277.5 52.9 1.9 <0.40 14.5 3.7 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 120.9 31.8 3.1 <0.40 22.5 11.1 <0.30 <0.10 <0. 10 <80 <3500 <14 <1.6 <10 142.8 42.8 3.0 <0.40 6.8 9.3 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 6.0 20.5 1.1 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 13.7 24.6 1.3 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 1 15.1 24.6 1.0 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 Compounds not investigated in this study.

PAGE 143

143 Table A 11 Concentrations of PAHs in leachate from column containing LC (ng/L) Leaching events Day 1 Day 2 Day 5 Day 8 Day 13 Day 18 Day 32 L/S ( L/Kg) 0. 04 0. 08 0. 2 0. 3 0. 5 0.7 1. 2 PAH Chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluo ranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h ) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 79.1 74.3 6.3 <0.40 47.5 19.8 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 1.4 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 1.3 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 3.0 <0.40 <1.1 10.9 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 429.7 <0.70 <0.80 1.7 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 283.0 <0.70 <0.80 1.1 <0.40 <1.1 <0.30 <0 .30 <0.10 <0.10 <80 <3500 <14 <1.6 413.1 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 Compounds not investigated in this study.

PAGE 144

144 Table A 12 Concentrations of PAHs in leachate from column containing JAX (ng/L) Leaching events D ay 1 Day 2 Day 5 Day 8 Day 13 Day 18 Day 32 L/S (L/Kg) 0.0 4 0. 08 0. 2 0. 3 0. 5 0.7 1. 2 PAH Chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluo ranthene Pyrene Benzo(k) Fluoranthene Chrysene Benzo (g,h,i)perylene Be n zo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo(b) fluoranthene Indeno 1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 <0.70 <0.80 2.4 <0.40 <1.1 <0.30 <0.30 <0.10 11.9 <80 <3500 <14 <1.6 <10 <0.70 15.7 1.6 <0.40 <1.1 3.6 <0.30 <0.10 4.2 <80 <3500 <14 <1.6 <10 28.0 32.0 2.4 <0.40 <1.1 11.5 <0.30 <0.10 0.0 <80 <3500 <14 <1.6 <10 60.4 50.0 2.9 <0.40 <1.1 13.6 <0.30 <0.10 18.2 <80 <3500 <14 <1.6 <10 <0.70 20.0 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 7.2 <80 <3500 <14 <1.6 <10 19.8 32.0 2.0 <0.40 <1.1 4.5 <0.30 <0.10 8.4 <80 <3500 <14 <1.6 206.3 58.7 23.2 1.5 <0.40 <1.1 <0.30 <0.30 <0.10 6.3 Compounds not investigated in this study.

PAGE 145

145 Table A 13 Concentrations of PAHs in leachate from column containing GNV (ng/L) Leac hing events Day 1 Day 2 Day 5 Day 8 Day 13 Day 18 Day 32 L/S (L/Kg) 0.0 4 0. 08 0. 2 0. 3 0. 5 0.7 1. 2 PAH Chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluo ranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g ,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 120.3 87.3 10.8 <0.40 94.9 47.4 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 20.6 1.3 <0.40 <1.1 <0. 30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 12.1 0.8 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 16.6 1.4 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 1.1 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 < 80 <3500 <14 <1.6 <10 <0.70 19.3 2.2 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 9.7 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 Compounds not investigated in this study.

PAGE 146

146 Table A 14 Concentrations of PAHs in leachat e from column containing PEM (ng/L) Leaching events Day 1 Day 2 Day 5 Day 8 Day 13 Day 18 Day 32 L/S (L/Kg) 0.0 4 0. 08 0. 2 0. 3 0. 5 0.7 1. 2 PAH Chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluor anthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 188.9 104.8 10.2 <0.40 <1.1 25.8 <0.30 <0.10 23.8 <80 <3500 <14 <1.6 <10 100.8 47.7 3.3 <0.40 <1.1 7.9 <0.30 <0.10 12.8 <80 <3500 <14 <1.6 <10 121.8 53.0 6.0 <0.40 <1.1 17.5 <0.30 <0.10 22.0 <80 <3500 <14 <1.6 <10 220.3 94.6 9.6 <0.40 <1.1 28.1 <0.30 <0.10 26.7 <80 <3500 <14 <1.6 <10 55.5 20.2 1.1 <0.40 < 1.1 <0.30 <0.30 <0.10 6.0 <80 <3500 <14 <1.6 <10 104.2 26.6 2.6 <0.40 <1.1 5.2 <0.30 <0.10 8.5 <80 <3500 <14 <1.6 <10 134.2 32.5 1.7 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 Compounds not investigated in this study.

PAGE 147

147 Table A 15 Concentr ations of PAHs in leachate from column containing MAR (ng/L) Leaching events Day 1 Day 2 Day 5 Day 8 Day 13 Day 18 Day 32 L/S (L/Kg) 0.0 4 0. 08 0. 2 0. 3 0. 5 0.7 1. 2 PAH Chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthra cene Fluor anthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 26.4 44.5 2.8 <0.40 <1.1 7.3 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 25.3 27.4 1.9 <0.40 <1.1 11.2 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 149.3 68.7 6.1 <0.40 <1.1 25.3 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 1.4 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1. 6 <10 142.4 53.7 6.6 <0.40 <1.1 29.9 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 21.0 1.1 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 32.2 3.4 <0.40 <1.1 7.6 <0.30 <0.10 <0.10 Compounds not investigated in this study.

PAGE 148

148 Table A 16 Concentrations of PAHs in leachate from column without a sample (ng/L) Leaching events Day 1 Day 2 Day 5 Day 8 Day 13 Day 18 Day 32 L ( L ) 1 2 5 8 13 18 32 PAH Chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phen anthrene Anthracene Fluor anthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1 .1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 < 0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 Compounds not investigated in this study.

PAGE 149

149 Table A 17 Concentrations of PAHs in leachate from column containing BRN under saturated condition (ng/L) Leaching events Week 1 Week 2 Week 3 Week 4 Week 5 L/S (L/Kg) 0.62 1.23 1.85 2.47 3.08 PAH ch emicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1 ,2,3 cd) pyrene < 80 < 3,500 662 7 16 6 32 3 48 3 47 4 3 6 <0.4 70 2 26 3 38 3 5 5 14 7 < 80 < 3500 < 14 < 1. 6 249 4 161 9 85 3 3 6 <0.4 < 1. 1 5 7 42 1 8 4 22 9 < 80 < 3500 < 14 < 1. 6 1 481 112 6 86 2 2 6 <0.4 < 1. 1 6 4 26 9 <0.1 0 8 8 < 80 < 3500 4.2556 < 1 6 1086 7 22 3 54 0 3 2 <0. 4 < 1.1 <0.3 0 0.0150 <0.1 0 <0.1 0 < 80 < 3500 2 095 2 < 1. 6 555 4 <0.0007 47 2 <0.2 <0.4 < 1.1 <0.3 0 13 5 <0.1 0 <0.1 0 Compounds not investigated in this study. Table A 18 Concentrations of PAHs in leachate from column contai ning JAX under saturated condition (ng/L) Leaching events Week 1 Week 2 Week 3 Week 4 Week 5 L/S (L/Kg) 0.38 0.75 1.13 1.51 1.88 PAH chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) F luoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 <0.70 25.5 1.3 <0.40 51.6 <0.30 7.5 <0.10 5.4 <80 <3500 <14 <1.6 <10 <0.70 2 6.5 1.0 <0.40 119.2 <0.30 13.0 <0.10 12.3 <80 <3500 <14 <1.6 <10 <0.70 32.7 0.8 <0.40 138.0 <0.30 16.2 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 37.7 1.2 <0.40 118.0 <0.30 11.5 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 24.5 <0.20 <0.40 91.0 <0.30 <0.30 <0.10 9.1 Compounds not investigated in this study.

PAGE 150

150 Table A 1 9 Concentrations of PAHs in leachate from column containing PEM under saturated condition (ng/L) Leaching events Week 1 Week 2 Week 3 Week 4 Week 5 L/S (L/Kg) 0.38 0.76 1.14 1.52 1.90 P AH chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Inde no (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 6.7 23.7 1.1 <0.40 83.7 <0.30 <0.30 <0.10 4.2 <80 <3500 <14 <1.6 <10 <0.70 20.3 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 21.1 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 23.5 0.8 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 20.4 1.7 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 Compounds not investigated in this study. Table A 20 Concentrations of PAHs in leachate from column containin g MAR under saturated condition (ng/L) Leaching events Week 1 Week 2 Week 3 Week 4 Week 5 L/S (L/Kg) 0.35 0.70 1.05 1.40 1.75 PAH chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluo ranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 <0.70 38.2 1.3 <0.40 30.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 1.0 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 28.9 8.0 32.1 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 31.8 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 38.0 <0.20 <0.40 <1.1 <0.30 < 0.30 <0.10 <0.10 Compounds not investigated in this study.

PAGE 151

151 Table A 21 Concentrations of PAHs in leachate from column containing LC under saturated condition (ng/L) Leaching events Week 1 Week 2 Week 3 Week 4 Week 5 L/S (L/Kg) 0.40 0.80 1.20 1.60 2. 00 PAH chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 <0.70 24.5 <0.20 <0.40 91.0 <0.30 8.6 <0.10 9.1 <80 <3500 <14 <1.6 <10 <0.70 45.2 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 < 80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 Compounds not investigated in this study. Table A 22 Concentrations of PAHs in leachate from co lumn containing GNV and GNV duplicate under saturated condition (ng/L) Leaching events Week 1 Week 2 Week 3 Week 4 Week 5 L/S (L/Kg) 0.38 0.76 1.14 1.51 1.90 PAH chemicals Naphthalene Acenaphthylene Acenaphthene Fluorene Phenanthrene Anthracene Fl uoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene Indeno (1,2,3 cd) pyrene <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0 .10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1.6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 <80 <3500 <14 <1 .6 <10 <0.70 <0.80 <0.20 <0.40 <1.1 <0.30 <0.30 <0.10 <0.10 Compounds not investigated in this study.

PAGE 152

152 Table A 23 Fractionation results of ditch cleaning sediment in mg/Kg Size Fraction 75 150 212 212 PAH Chemicals Dup Naphthalene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo ( b) fluoranthene Indeno (1,2,3 cd) pyrene 3.09 0.76 0.14 2.21 2.40 0.10 2.61 8.68 2.51 1.44 2.06 0.93 3.44 0.62 0.43 0.05 1.28 1.16 0.09 1.05 2.98 0.96 0.35 0.70 0.36 1.06 0.36 0.20 0.02 0.42 0.47 0.03 0.32 0.79 0.26 0.15 0.22 0.08 0.27 0.21 0.11 0.01 0.15 0.28 0.02 0.20 0.52 0.17 0.10 0.16 0.05 0.17 0.33 0.17 0.04 0.38 0.49 0.05 0.30 0.68 0.23 0.20 0.20 0.06 0.23 0.28 0.10 0.02 0.29 0.35 0.03 0.26 0.64 0.21 0.14 0.17 Table A 24 Fractionation results of catch basin sediment in mg/Kg Size Fraction <75 75 150 212 PAH Chemicals Naphthalene Phenanthrene Anthracene Fluoranthene Pyrene Benzo (k) Fluoranthene Chrysene Benzo (g,h,i)perylene Benzo (a)pyrene Benzo (a) anthracene Dibenzo (a,h) anthracene Benzo (b) fluoranthene I ndeno (1,2,3 cd) pyrene 1.43 0.38 0.07 1.12 1.03 0.04 1.05 2.88 1.14 0.58 0.21 0. 90 2.77 0.61 0.10 1.56 1.40 0.10 1.15 3.0 0.99 0.66 0.26 0.19 0.04 2.59 0.58 0.09 1.33 1.16 0.09 0.98 2.69 0.85 0.53 0.32 0.19 0.7 2 1.22 0.36 0.05 0.93 0.84 0.06 0.64 1.78 0 .54 0.37 0.22 0.13 0.5 5 4 .46 1.14 0.18 2.91 2.54 0.26 1.69 4.25 1.32 1.33 0.45 0.29 1.2 6

PAGE 153

153 APPENDIX B SUPPLEMENTARY FIGURE S Figure B 1 Picture of ditch cleaning Figure B 2 Picture of ditch clea ning

PAGE 154

154 A B Figure B 3. Distribution of PAHs in catch basin samples. A) distribution of n aphthalene B) distribution of a cenaphthene

PAGE 155

155 A B Figure B 4. Distribution of PAHs in catch basin samples. A) distribution of p henanthrene B) distribution of a nthracene

PAGE 156

156 A B Figure B 5. Distrib ution of PAHs in catch basin samples. A) distribution of f luoranthene B) distribution of p yrene

PAGE 157

157 A B Figure B 6. Distribution of PAHs in catch basin samples. A) distribution of b enzo(k) f luoranthene B) distribution of c hrysene

PAGE 158

158 A B Figure B 7. Distribution of PAHs in catch basin samples. A) distribution of b enzo(g,h,i)perylene B) distribution of b enzo(a)py rene

PAGE 159

159 A B Figure B 8. Distribution o f PAHs in leached catch basin samples A) distribution of a cenaphthene B) distribution of p henanthrene

PAGE 160

160 A B Figure B 9. Distribution of PAHs in leached catch basin samples A) d istribution of a nthracene B) distribution of f luoranthene

PAGE 161

161 A B Figure B 10. Distribution of PAHs in leached catch basin samples A) distribution of b enzo (k) Fluoranthene B) dist ribution of p yrene

PAGE 162

162 A B Figure B 11. Distribution of PAHs in leached catch basin samples A) distribution of b enzo (g,h,i)perylene B) distribution of b enzo(a)pyrene

PAGE 163

163 A B Figure B 12. Distribution of PAHs in leached catch basin samples A) distribution of n aphthalene B) distribution of a cenaphthene

PAGE 164

164 A B Figure B 13. Distribution of PAHs in leached catch basin samples A) distribution of p henanthrene B) distribution of a nthracene

PAGE 165

165 A B Figure B 14. Distribution of PAHs in leached catch basin samples A) distribution of f luoranthene B) distribution of p yrene

PAGE 166

166 A B Figure B 15. Distribution of PAHs in leached catch basin samples A) distribution of b enzo (k) Fluoranthene B) distribution of c hrysene

PAGE 167

167 A B Figure B 16. Distribution of PAHs in leached catch basin samples A) distribution of b enzo(g, h,i)perylene B) distribution of b enzo(a)pyrene

PAGE 168

168 A B Figure B 17. Distribution of PAHs in leached catch basin samples A) distribution of b enzo(a)anthracene B) distribution of b e nzo(b)fluoranthene

PAGE 169

169 LIST OF REFERENCES Ahrens, M.J., Depree, C.V., 2004. Inhomogeneous distribution of polycyclic aromatic hydrocarbons in different size and density fractions of contaminated sediment from Auckland Harbour, New Zealand: an opportunity fo r mitigation. Marine Pollution Bulletin 48, 341 350. Barranco, A., Alonso Salces, R.M., Bakkali, A., Berrueta, L.A., Gallo, B., Vicente, F., Sarobe, M., 2003. Solid phase clean up in the liquid chromatographic determination of polycyclic aromatic hydrocar bons in edible oils. Journal of Chromatography A 988, 33 40. Birgistottir, H., Gamst, J., Christensen, T.H., 2007. Leaching of PAHs from Hot Mix Asphalt Pavements. Environmental Engineering Science 24, 1409 1422. Bojes, H.K., Pope, P.G., 2007. Characteri zation of EPA's 16 priority pollutant polycyclic aromatic hydrocarbons (PAHs) in tank bottom solids and associated contaminated soils at oil exploration and production sites in Texas. Regulatory Toxicology and Pharmacology 47, 288 295. Brandt, H.C.A., de Groot, P.C., 2001. Aqueous leaching of polycyclic aromatic hydrocarbons from bitumen and asphalt. Water Research 35, 4200 4207. Brantley, A.S., Townsend, T.G., 1999. Leaching of Pollutants from Reclaimed Asphalt Pavement. Environmental Engineering Science 16, 105 116. Cerniglia, C.E., 1993. Biodegradation of polycyclic aromatic hydrocarbons. Biodegradation, Current Opinion in Biotechnology 4, 351 368. Cerniglia, C.E., Heitkamp, M.A., 1989. Microbial degradarion of polycyclic aromatic hydrocarbons in the aquatic environment. In Varanasi, u. (Ed.), Metabolism of polycyclic aromatic hydrocarbons in the aquatic environment. CRC Press, Boca Raton, pp 42 64. Collins, J.F., Brown, J.P., Alexeeff, G.V., Salmon, A.G., 1998. Potency Equivalency Factors for Some Po lycyclic Aromatic Hydrocarbons and Polycyclic Aromatic Hydrocarbon Derivatives. Regulatory Toxicology and Pharmacology 28, 45 54. Dipple, A., Anita, C., Bigger, H., 1991. Mechanism of action of food associated polycyclic aromatic hydrocarbon carcinogens. Mutation Research/Genetic Toxicology 259, 263 276. EPA, 2007. SW 846 Test methods for evaluating solid waste, physical/ chemical test methods. Office of Solid Waste

PAGE 170

170 FDEP, 2004. Evaluation of analytical data characterizing street sweepings, stormwater sed iments and catch basin sediments. Solid waste section. Florida department of environmental protection. Tallahassee, Florida. FDEP, 2005. Development of cleanup target levels (CTLs) for chapter 62 777, F.A.C., Final technical report: Division of waste mana gement, Florida department of environmental protection (FDEP). Freeman, D.J., Cattell, F.C.R., 1990. Woodburning as a source of atmospheric polycyclic aromatic hydrocarbons. Environmental Science & Technology 24, 1581 1585. Gron, C., Oomen, A., Weyand, E ., Wittsiepe, J., 2007. Bioaccessibility of PAH from Danish soils. Journal of Environmental Science & Health, Part A: Toxic/Hazardous Substances & Environmental Engineering 42, 1233 1239. Hack, A., Selenka, F., 1996. Mobilization of PAH and PCB from conta minated soil using a digestive tract model. Toxicology Letters 88, 199 210. Hardin J A, Hinoshite F, H, S.D., 1992. Mechanisms by which benzo[a]pyrene, an environmental carcinogen, suppresses B cell lymphopoesis. Toxicology and Applied Pharmacology. Harv ey, R.G., 1997. Polycyclic aromatic hydrocarbons: Chemistry and carcinogenicity. Cambridge university press, U.K. Henner,P., Schiavon, M., Morel, J., E., Lichtfouse E., 1997. Polycyclic aromatic hydrocarbons (PAH) occurrence and remediation methods.Analus is Magazine 25, M56 M59, Holman, H.N., 2000. U.S. Patent 6,040,188: In Oral Bioaccessibility of Dioxins/Furans at Fehling, D. J. Paustenbach, B. D. Landenberger, and M. P. Holsapple, 2002. Jang Y., Town send, T.G., 2001. Occurrence of organic pollutants in recovered soil fines from construction and demolition waste. Waste Management 21, 703 715. Johnson, A.C., Larsen, P.F., Gadbois, D.F., Humason, A.W., 1985. The distribution of polycyclic aromatic hydro carbons in the surficial sediments of Penobscot Bay (Maine, USA) in relation to possible sources and to other sites worldwide. Marine Environmental Research 15, 1 16. Jones, K.C., Stratford, J.A., Tidridge, P., Waterhouse, K.S., Johnston, A.E., 1989. Poly nuclear aromatic hydrocarbons in an agricultural soil:long term changes in profile distribution

PAGE 171

171 Juhasz, A.L., Naidu, R., 2000. Bioremediation of high molecular weight polycyclic aromatic hydrocarbons: a review of the microbial degradation of benzo[a]pyr ene. International Biodeterioration & Biodegradation 45, 57 88. Krein, A., Schorer, M., 2000. Road runoff pollution by polycyclic aromatic hydrocarbons and its contribution to river sediments. Water Research 34, 4110 4115. Laflamme, R.E., Hites, R.A., 19 78. The global distribution of polycyclic aromatic hydrocarbons in recent sediments. Geochimica et Cosmochimica Acta 42, 289 303. Legraverend, C., Harrison, D.E., Ruscetti, F.W., Nebert, D.W., 1983. Bone marrow toxicity induced by oral benzo[a]pyrene: Pro tection resides at the level of the intestine and liver. Toxicology and Applied Pharmacology 70, 390 401. Legret, M., Odie, L., Demare, D., Jullien, A., 2005. Leaching of heavy metals and polycyclic aromatic hydrocarbons from reclaimed asphalt pavement. W ater Research 39, 3675 3685. Lijinsky, W., 1991. The formation and occurrence of polynuclear aromatic hydrocarbons associated with food. Mutation Research/Genetic Toxicology 259, 251 261. Mackenzie, K.M., Angevine, D.M., 1981. Infertility in Mice Exposed in utero to Benzo(a)pyrene. Biology of Reproduction 24, 183 191. Marble, L.K., Delfino, J.J., 1988. Extraction and solid phase cleanup methods for pesticides in sediment and fish. American Laboratory (Shelton, CT, United States) 20(11), 23 4, 26, 28, 30 32 CODEN: ALBYBL 20, Maruya, K.A., Risebrough, R.W., Horne, A.J., 1996. Partitioning of Polynuclear Aromatic Hydrocarbons between Sediments from San Francisco Bay and Their Porewaters. Environmental Science & Technology 30, 2942 2947. Mercier, G., Duc hesne, J., Carles Gibergues, A., 2002. A simple and fast screening test to detect soils polluted by lead. Environmental Pollution 118, 285 296. Miles, C.J., Delfino, J.J., 1999. Priority Pollutant Polycyclic Aromatic Hydrocarbons in Florida Sediments. Bul letin of Environmental Contamination and Toxicology 63, 226 234. Morrison, R.T., Boyd, R.N., 1987. Organic Chemistry. Allyn and Bacon, Inc. Newton Massachusetts. Nisbet, I.C.T., LaGoy, P.K., 1992. Toxic equivalency factors (TEFs) for polycyclic aromatic hydrocarbons (PAHs). Regulatory Toxicology and Pharmacology 16, 290 300.

PAGE 172

172 Nishioka, M., Chang, H.C., Lee, M.L., 2002. Structural characteristics of polycyclic aromatic hydrocarbon isomers in coal tars and combustion products. Environmental Science & Techno logy 20, 1023 1027. Oleszczuk, P., Baran, S., 2004. Application of solid phase extraction to determination of polycyclic aromatic hydrocarbons in sewage sludge extracts. Journal of Hazardous Materials 113, 237 245. Oomen, A.G., Sips, A.J.A.M., Groten, J. P., Sijm, D.T.H.M., Tolls, J., 1999. Mobilization of PCBs and Lindane from Soil during in Vitro Digestion and Their Distribution among Bile Salt Micelles and Proteins of Human Digestive Fluid and the Soil. Environmental Science & Technology 34, 297 303. P aigen, B., Havens, M.B., Morrow, A., 1985. Effect of 3 Methylcholanthrene on the Development of Aortic Lesions in Mice. Cancer Res 45, 3850 3855. Penn, A., Batastini, G., Soloman, J., Burns, F., Albert, R., 1981. Dose dependent Size Increases of Aortic Le sions following Chronic Exposure to 7,12 Dimethylbenz(a)anthracene. Cancer Res 41, 588 592. Poster, D., Schantz, M., Sander, L., Wise, S., 2006. Analysis of polycyclic aromatic hydrocarbons (PAHs) in environmental samples: a critical review of gas chromat ographic (GC) methods. Analytical & Bioanalytical Chemistry 386, 859 881. Pu, X., Lee, L.S., Galinsky, R.E., Carlson, G.P., 2004. Evaluation of a Rat Model versus a Physiologically Based Extraction Test for Assessing Phenanthrene Bioavailability from Soil s. Toxicological Sciences 79, 10 17. Ramesh, A., Walker, S.A., Hood, D.B., Guilln, M.D., Schneider, K., Weyand, E.H., 2004. Bioavailability and Risk Assessment of Orally Ingested Polycyclic Aromatic Hydrocarbons. International Journal of Toxicology 23, 301 333. Ruby, M.V., Davis, A., Kempton, J.H., Drexler, J.W., Bergstrom, P.D., 2002a. Lead Bioavailability Dissolution Kinetics under Simulated Gastric Conditions. Environmental Science & Technology 26, 1242 1248. Ruby, M.V., Davis, A., Schoof, R., Ebe rle, S., Sellstone, C.M., 1996. Estimation of Lead and Arsenic Bioavailability Using a Physiologically Based Extraction Test. Environmental Science & Technology 30, 422 430. Ruby, M.V., Fehling, K.A., Paustenbach, D.J., Landenberger, B.D., Holsapple, M.P. 2002b. Oral Bioaccessibility of Dioxins/Furans at Low Concentrations (50 350 ppt Toxicity Equivalent) in Soil. Environmental Science & Technology 36, 4905 4911.

PAGE 173

173 Ruby, M.V., Schoof, R., Brattin, W., Goldade, M., Post, G., Harnois, M., Mosby, D.E., Caste el, S.W., Berti, W., Carpenter, M., Edwards, D., Cragin, D., Chappell, W., 1999. Advances in Evaluating the Oral Bioavailability of Inorganics in Soil for Use in Human Health Risk Assessment. Environmental Science & Technology 33, 3697 3705. Shiaris, M.P. Jambard Sweet, D., 1986. Polycyclic aromatic hydrocarbons in surficial sediments of Boston Harbour, Massachusetts, USA. Marine Pollution Bulletin 17, 469 472. Simpson, C.D., Harrington, C.F., Cullen, W.R., Bright, D.A., Reimer, K.J., 1998. Polycyclic Ar omatic Hydrocarbon Contamination in Marine Sediments near Kitimat, British Columbia. Environmental Science & Technology 32, 3266 3272. Skoog, D.A., Holler, F.J., Nieman, T.A., 1998. Principles of instrumental analysis, Fifth ed. Thomson learning, Inc, Uni ted States of America. Talley, J.W., Ghosh, U., Tucker, S.G., Furey, J.S., Luthy, R.G., 2002. Particle Scale Understanding of the Bioavailability of PAHs in Sediment. Environmental Science & Technology 36, 477 483. Townsend, T.G., 2002. Characterization of street sweepings, stormwater sediments, and catch basin sediments, in Florida for disposal and reuse: Final report. Florida Department of Environmental Protection. USEPA, 1991. Intergrated risk information system (IRIS). Chemical specific reference dos es and cancer potency factors and EPA toxicology background documents. Office of health and environmental criteria and assessment office, Cincinnati, Ohio. Wang, X. C., Zhang, Y. X., Chen, R.F., 2001. Distribution and Partitioning of Polycyclic Aromatic H ydrocarbons (PAHs) in Different Size Fractions in Sediments from Boston Harbor, United States. Marine Pollution Bulletin 42, 1139 1149. Wild, S.R., Jones, K.C., 1995. Polynuclear aromatic hydrocarbons in the United Kingdom environment: A preliminary sourc e inventory and budget. Environmental Pollution 88, 91 108. Wittsiepe, J., Schrey, P., Hack, A., Selenka, F., Wilhelm, M., 2001. Comparison of different digestive tract models for estimating bioaccessibility of polychlorinated dibenzo p dioxins and dibenz ofurans (PCDD/F) from red slag. International Journal of Hygiene and Environmental Health 203, 263 273. Youngblood, W.W., Blumer, M., 1975. Polycyclic aromatic hydrocarbons in the environment: homologous series in soils a nd recent marine sediments. Geochimica et Cosmochimica Acta 39, 1303 1314.

PAGE 174

174 BIOGRAPHICAL SKETCH Edmund Azah was born in Ghana. After completing the basic and senior high schools, he gained admission into Kwame Nkrumah University of Science and T echnology Kumasi, Ghana He graduated in 1997 with a c hemistry and proceeded to work in production management and quality control in Ghana until he gained admission into Tuskegee University, Alabama He grad uated from Tuskegee University in 2007 with in c hemistry and joined the University of Florida that same year. He received his PhD in e nvironmental e ngineering s cience in 2011 under the tutorage of Dr Timothy Townsend.