Citation
Examination of Environmental Risks Posed by Construction and Demolition Debris Fines and Asphalt Construction Products

Material Information

Title:
Examination of Environmental Risks Posed by Construction and Demolition Debris Fines and Asphalt Construction Products
Creator:
Su, Jing
Publisher:
University of Florida
Publication Date:
Language:
English

Thesis/Dissertation Information

Degree:
Master's ( M.S.)
Degree Grantor:
University of Florida
Degree Disciplines:
Environmental Engineering Sciences
Committee Chair:
TOWNSEND,TIMOTHY G
Committee Co-Chair:
WU,CHANG-YU
Committee Members:
MA,LENA Q

Subjects

Subjects / Keywords:
cdd
fines

Notes

General Note:
Construction and demolition debris (CDD) fines are a common residue that is generated during the processing of CDD in a recycling facility. To mitigate the health risks associated with beneficially reusing CDD fines as either unrestricted fill or landfill cover, the concentrations of chemicals of major concern must be evaluated for risk. Four chemicals of most concern include arsenic, lead, sulfate and polycyclic aromatic hydrocarbons (PAH), which were characterized. To help better understand the potential risk of PAH, research on the sources and bioaccessibility of PAH from asphalt products were further conducted. One experiment focused on measuring the four specific chemicals along with several other heavy metals in four different size fractions of CDD fines (< 0.30 mm; 0.30 mm to 0.84 mm; 0.84 mm to 4.8 mm; and 4.8 mm to 19 mm). Aluminum, arsenic and chromium concentrations were distributed evenly throughout all four size fractions. As for the remaining chemicals, most samples had lower concentrations in the 4.8 mm to 19 mm sample size range, with each chemical in this size range comprising less than 30% of the total mass. Another experiment focused on measuring PAH in different asphalt products mixed in clean sand in three different percentages (100%, 10%, and 1%). PAH concentrations were very low in most asphalt products, with the exception of one reclaimed asphalt pavement (RAP) sample which had high PAH concentrations. Its pure sample even exceeded 20 times of industrial/ commercial FSCTL of 0.7 mg/kg. Though PAH sources for asphalt products are petrogenic, diagnostic ratios determined in these samples did not show a clear petrogenic source for these materials. Thus, caution should be taken when using diagnostic ratios for source apportionment. In addition, the PAH bioaccessibility of these asphalt products were relatively low as well, with less than 40 % for new shingles and less than 10% for the other asphalt products. It was therefore concluded that concentrations of harmful chemicals can be reduced by removing finer CDD particles and the PAH would likely not pose a carcinogenic threat to human health.

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Source Institution:
UFRGP
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All applicable rights reserved by the source institution and holding location.
Embargo Date:
5/31/2019

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EXAMINATION OF ENVIRONMENTAL RISKS POSED BY CONSTRUCTION AND DEMOLITION DEBRIS FINES AND ASPHALT CONSTRUCTION PRODUCTS By JING SU A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLME NT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2017

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2017 Jing Su

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To my Mom and Dad

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4 ACKNOWLEDGMENTS I would like to thank my committee members for their unwavering support throughout my thesis work I would especially like to thank Dr. Timothy G. Townsend for his guidance, dedication and support for which I would not have received my MS degree without I humbly appreciat e the opportunity he provided me to work on var ious meaningful projects, allowing me to gain experience that will undoubtedly be valuable to my future endeavors I would also like to thank a lot to Steven Laux, who devoted a lot to help me with my w ork and in writing this thesis. Besides, I would like to thank the assistance provided by Dr. Lena Q. Ma and Dr. Chang Yu Wu as well as their graduate students especially Peng Gao The research presented was supported by the Construction and Demolition Debris Association and the Hinkley Center for Solid and Hazardous Waste Management and I would like to thank the se organization s for giving me the chance to complete the se project s I would lastly like to thank my parents for their love and encouragement in helping me finish my thesis and my fellow graduate st udents for their assistance with my work.

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5 TABLE OF CONTENTS page ACKNOWLEDGMENTS ................................ ................................ ................................ ............... 4 LIST OF TABLES ................................ ................................ ................................ ........................... 7 LIST OF FIGURES ................................ ................................ ................................ ......................... 9 LIST OF ABBREVIATIONS ................................ ................................ ................................ ........ 11 ABSTRACT ................................ ................................ ................................ ................................ ... 13 CHAPTER 1 INTRODUCTION ................................ ................................ ................................ .................. 15 1.1 Background and Problem Statement ................................ ................................ ............ 15 1.2 Research Objectives ................................ ................................ ................................ ..... 17 1.3 Research Approach ................................ ................................ ................................ ...... 17 1.4 Organization of Thesis ................................ ................................ ................................ 18 2 TRACE CHEMICAL PARTITIONING IN CONSTRUCTION AND DEMOLITION DEBRIS FINES: PROCESS AND MARKET IMPLICATIONS ................................ .......... 19 2.1. Introduction and Background ................................ ................................ .......................... 19 2.2 Methods and Materials ................................ ................................ ................................ ..... 23 2.2.1 Experimental Approach ................................ ................................ .......................... 23 2.2.2 Fines Processing and Cha racterization ................................ ................................ ... 24 2.2.3 Mass Balance Calculations ................................ ................................ ..................... 27 2.3 Results and Discussion ................................ ................................ ................................ ..... 27 2.3.1 Mass Distribution and Composition Study ................................ ............................. 27 2.3.2 VS Content ................................ ................................ ................................ ............. 28 2.3.3 Total Heavy Metal ................................ ................................ ................................ .. 29 2.3.4 Total PAH ................................ ................................ ................................ ............... 30 2.3.5 Sulfate ................................ ................................ ................................ ..................... 31 2.3.6 Risk Assessment and Mitigation Appro ach ................................ ........................... 31 2.4 Con clusion ................................ ................................ ................................ ........................ 32 3 CONTRIBUTION OF ASPHALT PRODUCTS TO EXTRACTABLE AND BIOACCESSIBLE POLYCYLIC AROMATIC HYDROCARBONS IN SOIL .................. 42 3.1 Introduction and Background ................................ ................................ ........................... 42 3.2 Method and Materials ................................ ................................ ................................ ....... 45 3.2.1 Experimental Approach ................................ ................................ .......................... 45 3.2.2 Sample Pre treatment ................................ ................................ ............................. 46 3.2.3 Extraction Procedures ................................ ................................ ............................. 46

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6 3.2.4 Analytical Procedures ................................ ................................ ............................. 47 3.2.5 PAH Diagnostic Ratios ................................ ................................ ........................... 48 3.2.6 BaP equivalent total PAH calculation ................................ ................................ .... 48 3.3 Results and Discussion ................................ ................................ ................................ ..... 48 3.3.1 Total Extractable PAHs ................................ ................................ .......................... 48 3.3.2 Diagnostic Ratios ................................ ................................ ................................ .... 51 3.3.3 PAH Bioaccessibility ................................ ................................ .............................. 52 3.3.4 Quality Control/ Quality Assurance (QA/QC) ................................ ....................... 53 3.4 Conclusion ................................ ................................ ................................ ........................ 53 4 SUMMARY AND CONCLUSION ................................ ................................ ....................... 59 4.1 Summary of Research ................................ ................................ ................................ ....... 59 4.2 Specific Observations ................................ ................................ ................................ ....... 60 4.3 Future Implications ................................ ................................ ................................ ........... 61 APPENDIX A FIGURES ................................ ................................ ................................ ................................ 62 B TABLES ................................ ................................ ................................ ................................ 66 LIST OF REFERENCES ................................ ................................ ................................ ............... 72 BIOGRAPHICAL SKETCH ................................ ................................ ................................ ......... 77

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7 LIST OF TABLES Table page 2 1 Sample letters with corresponding regions. ................................ ................................ ....... 34 2 2 VS content measured on different sieve sizes for the 14 samples in duplicate(%). .......... 34 2 3 Average As and Pb concentrations reside in the four size fractions for all 14 samples (mg/kg). ................................ ................................ ................................ .............................. 34 2 4 BaP equivalent total PAHs obtained on different size fractions and total weighted average BaP equivalent total PAH concentrations for all 14 samples in duplicate (mg/kg). ................................ ................................ ................................ .............................. 35 2 5 Number of samples chemical concentrations reduced by 25%, 50%, 75% when removing particle size of less than 4.8 mm and 0.84 mm ................................ .................. 35 3 1 De scription of eleven asphalt containing materials. ................................ .......................... 55 3 2 New asphalt shingle total extractable PAH concentrations in duplicate. (mg PAH/kg asphalt) ................................ ................................ ................................ ............................... 55 3 3 Aged asphalt shingle total extractable PAH concentrations in duplicate. (mg PAH/kg asphalt) ................................ ................................ ................................ ............................... 56 3 4 Reclaimed asphalt shingle total extractable PAH concentrations in duplicate. (mg PAH/kg asphalt) ................................ ................................ ................................ ................. 56 3 5 New asphalt pavement & fresh bitumen total extractable PAH concentrations in duplicate. (mg PAH/kg asphalt) ................................ ................................ ......................... 56 3 6 BaP equivalent total PAH of the 11 asphalt containing materials in duplicate. ................ 57 3 7 Detected diagnostic Ratios of pure samples. ................................ ................................ ..... 57 B 1 Table of 16 EPA Priority PAHs. ................................ ................................ ........................ 66 B 2 Mass distribution on different sieve sizes in duplicate (g). ................................ ............... 67 B 3 VS content measured on different sieve sizes in duplicate (g). ................................ ......... 67 B 4 As concentrations on different sieve sizes and the total weighted average As concentrations for all 14 samples in triplicate(mg/kg) ................................ ...................... 67 B 5 Pb concentrations on different sieve sizes and the total weighted average Pb concentrations for all 14 samples in triplicate (mg/kg) ................................ ..................... 68 B 6 Gypsum content for 14 samples obtained on different size fractions in duplicate. ........... 68

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8 B 7 Al concentrations on different sieve sizes and the total weighte d average Al concentrations for all 14 samples in triplicate (mg/kg) ................................ ..................... 69 B 8 Cd concentrations on different sieve sizes and the total weighted average Cd concentrations for all 14 samples in tr iplicate (mg/kg) ................................ ..................... 69 B 9 Cr concentrations on different sieve sizes and the total weighted average Cr concentrations for all 14 samples in triplicate (mg/kg) ................................ ..................... 69 B 10 Cu concentrations on different sieve sizes and the total weighted average Cu concentrations for all 14 samples in triplicate (mg/kg) ................................ ..................... 70 B 11 Ni concentrati ons on different sieve sizes and the total weighted average Ni concentrations for all 14 samples in triplicate (mg/kg) ................................ ..................... 70 B 12 Zn concentrations on different sieve sizes and the total weighted average Zn concentrations for all 14 samples in triplicate (mg/kg) ................................ ..................... 70 B 13 Florida SCTL and National RSL for detected chemicals (mg/kg) ................................ .... 71

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9 LIST OF FIGURES Figure page 2 1 Average percentage mass of each size fraction and cumulative percentage of CDD fine components ................................ ................................ ................................ ................ 36 2 2 Comparison of mass distribution as a function of particle size for 14 samples in duplicate ................................ ................................ ................................ ............................. 37 2 3 Comparison of VS mass distribution as a function of particle size for 14 samples in duplica te ................................ ................................ ................................ ............................. 37 2 4 Comparison of As concentration mass distribution as a function of particle size for 14 samples in triplicate ................................ ................................ ................................ ...... 38 2 5 Co mparison of Pb concentration mass distribution as a function of particle size for 14 samples in triplicate ................................ ................................ ................................ ...... 38 2 6 BaP equivalent total PAH mass distribution as a function of particle size for 11 detected samples in duplicate ................................ ................................ ............................. 39 2 7 Sulfate concentration mass distribution as a function of particle size for 14 samples in duplicate ................................ ................................ ................................ ......................... 39 2 8 Risk assessment for As Pb, PAH and sulfate when continuously removing each of the finer size fraction ................................ ................................ ................................ ......... 40 3 1 Average PAH Bioaccessibility of 100%, 10% & 1% asphalt products in duplicate ......... 58 3 2 PAH diagnostic ratios based on PAH molecular weight ................................ ................... 58 A 1 Mixed CDD processing diagram ................................ ................................ ....................... 62 A 2 Comparison of Al concentration mass distribution as a function of particle size for 14 samples in triplicate ................................ ................................ ................................ ........... 62 A 3 Comparison of Cd concentr ation mass distribution as a function of particle size for 14 samples in triplicate ................................ ................................ ................................ ...... 63 A 4 Comparison of Cr concentration mass distribution as a function of particle size for 14 samples in tri plicate ................................ ................................ ................................ ........... 63 A 5 Comparison of Cu concentration mass distribution as a function of particle size for 14 samples in triplicate ................................ ................................ ................................ ...... 64 A 6 Comparison of Ni concentration mass distribution as a function of particle size for 14 samples in triplicate ................................ ................................ ................................ ........... 64

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10 A 7 Comparison of Zn concentration mass distribution as a function of particl e size for 14 samples in triplicate ................................ ................................ ................................ ...... 65 A 8 Composition study of 14 samples on different size fractions ................................ ............ 65

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11 LIST OF ABBREVIATIONS ACY Acena phthylene ACE AN ANC/ Ant BaA BaP BbF BcF BkF BP/ BPE CDD CH/ Chr DeP DhA DiP DlP FL FLU/ Flt GC MS IC ICP AES i.d. I P/ IPY NA Acenaphthene Anthanthrene Anthracene Benzo[a]anthracene Benzo[a]pyrene Benzo[b]fluoranthene Be nzo[c]fluorine Benzo[k]fluoranthene Benzo[g,h,i]perylene Construction and Demolition Debris Chrysene Dibenzo[a,e]pyrene Dibenz[a,h]anthracene Dibenzo[a,i]pyrene Dibenzo[a,l]pyrene Fluorene Fluoranthene Gas Chromatography mass spectrometry Ion Chromatograhy Inductively coupled plasma atomic emission spectroscopy Internal Diameter Indeno[1,2,3 cd]pyrene Naphthalene

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12 PAH PH/ Phe PY/ Pyr SCTL SD VS Polycyclic Aromatic Hydrocarbon Pyrene Phenanthrene Soil Cleanup Target Level Standard Deviation Volatile Solids

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13 Abstract of Thesis Presente d to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science EXAMINATION OF ENVIRONMENTAL RISKS POSED BY CONSTRUCTION AND DEMOLITION DEBRIS FINES AND ASPHALT CONSTRUCT ION PRODUCTS By Jing Su May 2017 Chair: Timothy G. Townsend Major: Environmental Engineering Sciences Construction and demolition debris (CDD) fines are a common residue that is generated during the processing of CDD in a recycling facility. To mitigat e the health risks associated with beneficially reusing CDD fines as either unrestricted fill or landfill cover, the concentrations of chemicals of major concern must be evaluated for risk Fou r chemicals of most concern include arsenic, lead, sulfate and polycyclic aromatic hydrocarbons (PAH) which were characterized To help better understand the potential risk of PAH, research on the sources and bioaccessibility of PAH from asphalt products were further conducted. One experiment focused on measuring the four specific chemicals along with several other heavy metals in four different size fractions of CDD fines (< 0.30 mm; 0.30 0.84 mm; 0.84 4.8 mm; and 4.8 19 mm). Aluminum, arsenic and chromium concentrations were distributed evenly t hroughout all f our size fractions. As for th e remaining chemicals, most samples ha d lower concentrations in the 4 .8 19 mm sample size range, with each chemical in this size range comprising less than 30% of the total mass Another experiment focused on measuring PAH in different asphalt products mixed in clean sand in three different percentages (100%, 10%, and 1%). PAH concentrations were very low in most asphalt products, with the

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14 exception of one reclaimed asphalt pavement (RAP) sample which had high PAH concentratio ns. Its pure sample even exceeded 20 times of industrial/ commercial FSCTL of 0.7 mg/kg Though PAH sources for asphalt products are petrogenic, diagnostic ratios d etermined in these samples did no t show a clear petrogenic source for these materials. Thus, caution should be taken when using diagnostic ratios for source apportionment In addition, PAH bioaccessibility of these asphalt products were relatively low as well with less than 40 % for new shingles and less than 10% for the other asphalt products. It was t herefore concluded that concentrations of harmful chemicals can be reduced by removing finer CDD particles and the PAH would likely not pose a carcinogenic threat to human health.

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15 CHAPTER 1 INTRODUCTION 1.1 Background and Problem Statement Constru ction and demolition debris (CDD) is a component of the waste steam that is generated during the construction and demolition of structures and other infrastructure (Townsend et al., 2004). Construction and demolition debris components mainly include wood, gypsum, asphalt (roofing and pavement), concrete, and small amounts of metal, plastic and paper. According to the United States (US) Environmental Protection Agency (EPA), total CDD generation in the US was 534 million tons in 2014 (US EPA, 2016). Much o f this material is collected and sent to CDD recycling facilities, where it is separated into various components that are repurposed for other uses, such as recycled concrete aggregate, recycled asphalt p avemen t, mulch, boiler fuel, and fill material CDD fi nes are produced when mixed CDD is processed using screens that have various opening sizes ( depending on the screening objective) These fines contain small pieces of concrete, asphalt, wood, plastic, gypsum drywall, soil and other CDD components. Although these components are generally inert, CDD fines may contain c hemicals that limit their use as a recycled material Four main chemicals of concern are arsenic, lead, sulfate and polycycl ic aromatic hydrocarbons (PAHs) (Jang and Townsend, 2001; Townsend et al., 2004 ) State environmental protection agencies usually have risk based regulatory threshold s for arsenic, lead and PAH although many states do not have clear regulatory thresholds for sulfate. These regulatory thresholds vary by state Thresholds for PAH (refer enced to b enzo[a]pyrene equivalent ) and lead are often of similar magnitude, w hile r egulatory thresholds for arsenic vary from state often by order s of magnitude. For example, Florida reside ntial soil cleanup target level (SCTLs) for arsenic i

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16 use is 20 mg/ kg (FDEP, 2005; Washington State Department of Ecology, 2014 ). Some states have higher arsenic risk thresholds as they consider arsenic b ackground soil concentrations in setti ng their regulatory threshold. Sources of trace chemicals in CDD fines contaminants are from a combination of soils that have been exposed to CDD components and small pieces of the components themselves that are mixed into the fines. These components incl ude treated wood lumber (e.g. chromated copper arsenate treated wood), lead based paint, gypsum drywall, asphalt pavement and roofing materials, and other materials. Soil in the CDD fines may be contaminated by chemical spills on the cons truction or decon struction site exposure to chemicals leached from the CDD components, and vehicle emissions from roadside construction or deconstruction sites Some chemicals, such as arsenic and lead, are naturally present in the soil Past research h as shown that arsen ic and b enzo[a] pyrene in CDD fines sometimes exceeded Florida SCTL, while for other chemicals, concentrations were below regulatory thresholds Townsend et al., (2004) detected the average arsenic concentration out of 46 CDD samples to be 3.2 mg/kg, which exceeded the old residential FL SCTL (0.8 mg/kg); other research in 2001 also detected an average benzo[a]p yrene concentration of 55.1 mg/kg across 12 samples which exceeded the old industrial FL SCTL (0.5 mg/kg) (Townsend et al., 2004; Jang and Townsend, 2001). This research investigates two distinct but related research issues with regard to CDD fines. First, concentrations of arsenic, lead, sulfate, and PAH in four different size fractions of CDD fines to determine if these contaminants are concentrat ed in part icular fractions of the matrix. If this is the case, it may be possible to reduce concentrations of these contaminants from the CDD fines using a m echanical screening process, thereby expanding potential beneficial

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17 reuse opportunities for this ma terial. Second, a closer examination of PAH of asphalt materials in CDD fines is included PAH compounds are occas ionally found in CDD fines at concentrations above risk thres holds. A common belief in the CDD industry is the majority of PAH in CDD fines ar e small pieces of asphalt materials. Sources of asphalt would include asphalt shingles and asphalt pavement. If asphalt was present i n CDD fines and subjected to the solvent extraction conditions in the PAH testing procedures, PAH would be detected This i n turn suggests that PAH from asphalt may not pose the risk suggested by the concentration alone because it may be bound in the asphalt matrix. These issues require investigation. 1.2 Research Objectives The objectives of this research are as follows : To d eter mine trace chemical distribution in CDD fines as a function of particle size and to evaluate if concentrations in the bulk material can be reduced by removing certain particle size range s through screening To a nalyze total extractable PAH concentration s a nd associated bioaccessibility of different as phalt products to assess whether these products can account for the range of PAH concentrations in CDD fines, whether the PAH concentrations resulting from t hese products are bioaccessible, and what is the pote ntial PAH source. 1.3 Research Approach In Chapter 2, 14 CDD fine s samples provided by 12 recycling facilities around the US were examined These samples were dried and sieved into four different size fractions (< 0.30 mm; 0.30 0.84 mm; 0.84 4.8 mm and 4.8 19 mm). For each size fraction, volatile solids (VS) content was measured. Heavy metal concentrations were measured by digestion, and then analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy ( ICP AES ) Polycyclic aromatic h ydrocarbon con centrations were analyzed following the process of ultrasonic extraction, cleanup and gas chromatography mass s pectrometry (GC MS) analysis. Sulfate

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18 concentration was extracted according to the m ethod of Musson et al. ( 2008) and the leachate was analyzed b y ion c hromatography ( IC ) The percentage of total chemical mass in each size fraction was calculated to assess the particle size contributed to the largest percentage of each chemical. In addition to these chemical ana lysis, samples of larger than 19 mm w ere also obtained and the composition of this larger fraction was measured. In Chapter 3, 11 types asphalt products were characterized for PAH concentration and bioac c essibility After size reduction, each asphalt product was mixed with different amounts o f pure sand to form a 100 g composite sample of 100%, 10% and 1% asphalt mixture. Total extractable PAH concentrations were analyzed using the same method for PAH analysis as stated above while PAH bioaccessibility was analyzed according to the method used by Gomez Eyles (2012). Five diagnostic ratios were then used to evaluate potential sources of PAH contamination. 1.4 Organization of Thesis This thesis is organized into four chapters. The present c hapter consists of the introduction and background, objective s, approaches and organization sections. Chapter 2 discusses the research pertaining to the chemical analysis conducted for different size fractions of CDD fines. Chapter 3 presents the study on PAH of asphalt products. These PAH studies include total extr actable PAHs, PAH bioaccessibility and PAH diagnostic ratios. Chapter 4 provides a comprehensive conclusions of Chapter 2 and 3. Appendices A and B include additional information for Chapters 2 and 3, and a reference list is provided at the end of this the sis.

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19 CHAPTER 2 TRACE CHEMICAL PARTITIONING IN CONSTRUCTION AND DEMOLITION DEBRIS FIN ES: P ROCESS AND MARKET I MPLICATIONS 2.1 Introduction and Background Operators of construction and demolition debris (CDD) recycling facilities rely on screening as one processing step to separate and recover reusable commodities. A flow diagram showing the processing of mixed CDD is presented in Figure A 1. The screening operation normally occurs at the beginning of the recycling process in an effort to remove small size materials such as soil and fine pieces of concrete, wood, asphalt and drywall. The CDD fines screened from the larger sized CDD components represent a substantial portion of the material, often 20% of the mass or more. Screen sizes vary from facility to f acility; a Massachusetts CDD recyclers study (2008) reported that screen sizes in that state ranged from 9.5 mm to 76 mm. The Florida Department of Environmental Protection (2011), which established regulations and best management practices for the benefic ial reuse of CDD fines (which they call Recovered Screen Material), defines the material as being derived from the processing of CDD which passes through a final screen of size not greater than 19 mm. Typical beneficial use options are construction fill or landfill cover (Townsend et al., 2004). However, its use in these applications may be accompanied by potential environmental problems, such as groundwater and surface water contamination when used as an unrestricted fill, or odor problems when used as cov er in a landfill. Several potentially hazardous substances may be encountered in typical CDD, especially resulting from the demolition of older structures. Construction and demolition debr is components normally include P ortland cement concrete from founda tions, floor slabs, walls and pavement; metals from building structural framework, fasteners and miscellaneous hardware; wood from structural framework, flooring, doors, and window frames; gypsum from wallboard; glass from

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20 windows; and soil. Although the c omponents described above are relatively inert and account for the majority of the waste stream mass, the CDD waste stream may also include building components coated with paints containing heavy metals and PCB; insulation, floor tiles and mastics containi ng asbestos; asphalt roofing and bitumastic weather proofing products containing polycyc l ic aromatic hydrocarbon ( PAH ) ; wood debris containing arsenic, chromium and copper; electronic devices containing mercury and cadmium; and emergency lighting systems with batteries containing heavy met als. Even with conscientious efforts to remove these materials from the waste stream at the construction site and recycling facility, these materials can become part of the CDD waste stream to some degree and become a contamination source for the CDD fines As this material is broken up and crushed in the CDD recycling facility, gypsum particles from drywall and small pieces of coated debris, paint chips, broken insulation, and electronic components are mixed with soil and small aggregates in the waste stre am to form CDD fines. Additionally, the soil itself can become a source of heavy metal contamination; specific heavy metal concentrations in CDD fines have been found to be elevated in areas where the same naturally occurring heavy metals are elevated i n so il s (Tow nsend et al., 2004). PAHs are a gr oup of fused benzene rings that consists of more than 100 chemicals. Among these PAHs, the US EPA has identified 16 priority PAHs with in two groups: carcinogenic and non carcinogenic, where ni ne are non carcinogeni c and seven of them are carcinogenic (Azah, 2011; Banger et al., 2010). Among carcinogenic PAHs, BaP is the most toxic comp ound. High molecular weight PAHs (containing > 4 benzene rings) tend to have greater hydrophobicity (logKow > 5) resulting in longer residence times in soils (Banger et al., 2010) and most carcinogenic PAHs have high molecular weight. Potential PAH sources in CDD fines include pieces of asphalt products (pavement and roof shingles). For example, Legret et al.

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21 (2005) found PAH concentrations of 4.3 mg/kg and 1.8 mg/kg in new and aged asphalt PAH concentratio n s of 0.042 mg/kg and 0.96 mg/kg have also been detected in other construction materials such as concrete ( Wahlstrom et al. 2000) and bricks Another source of PAH may be soil, which is a major component of CDD fines. Organic matter in soils has a high affinity to PAH (Aichner et al., 2015), and may accumulate PAH from engine exh aust and spilled fuel and lubricants generated before and during the demolition process. PAH concentrations have been reported to be approximately 2000 mg/kg in diesel fuel (Dobbins et al., 2006; Schauer et al., 1999; Williams et al., 1986 ) A study of roadside soils indicated an a ve ra ge PAH concentrations of 1 87 mg/kg from these sources ( B anger et al., 2010 ). Wallboard contributes significant quantities of gypsum (CaSO 4 2 O) to CDD fines, which can lead to a large amount of sulfate leaching (Jang and Townsend, 2001). When used as landf ill cover, CDD fines have be en found to cause odor problems. H 2 S can be formed in a landfill w here organic serves as an electron donor and SO 4 2 serves as an electron a cceptor (Sun and Barlaz, 2015; Montero et al., 2010). When CDD fines are used as genera l fill, the high gypsum concentration s can cause sulfate contamination problems. A rsenic in CDD fines can originate from Chromated Cop per Arsenate (CCA) treated wood, where arsenic exists as As 2 O 5 (Solo Gabriele et al., 2002). Naturally occurring arsenic is also be present in soil ( Ma et al. 1997) which is a major component of CDD fines. Chen et al. (2001) found an average arsenic upper baseline concentration of 7.02 mg/kg in soil In many cases, naturally occu rring soil a rsenic concentration s have been found to be above regulatory risk thresholds ; usually because many states have very low thresholds for arsenic A common source of lead in CD D is lead based paint, which is defined by the US EPA as 2 or more

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22 Turner et al. (2016) determined the average concentration of lead to be 29300 mg/kg in exterior lead based paints. Lead concentration s may be elevated in soils close to structures with lead based paint or other lead containing materials Another source of lead may be petroleum contaminated soils which has been found to contain lead in conc entrations that range from 1.0 10900 mg/kg ( Mielke et al. 1983) L ow lead co ncentration s have also been detected in recycled asphalt product (7 mg/kg; Legret et al., 2005) new asphalt (3 mg/kg; Legret et al., 2005) and natural aggregates (5 mg/kg; Legret et al., 2005) as wells as concrete and bricks (10 mg/kg, Wahlstrom et al., 2000) Several research into the chemical composition of CDD fines has been performed in the past. Townsend, et al. (2004) evaluated samples from 13 Florida CDD processing f acilities for total and leachable concentrations of 11 different metals. Only arsenic exceeded both residential and industrial soil target cleanup levels (SCTL) in some samples, while other metals (nickel, chromium and copper) occasionally exceeded residen tial SCTLs. Jang and Townsend (2001) studied total PAH concentrations in 47 CDD fines samples from 12 recycling facilities and found that acenaphthene, pyrene, fluoranthene and phenanthrene were commonly detected. Benzo[a]pyrene was only detected once in that study, but the concentration was reported as 550 times higher than Florida Residential SCTL. They also performed sulfate leaching tests on CDD fines samples collected from 13 CDD recycling facilities throughout Florida and reported the gypsum content in their samples ranged from 1.5% 9.1% by mass. Musson et al. (2008) reported CDD fines to have sulfate content of 0.6% 21.2%. Montero et al. ( 2010) reported that gypsum in CDD fines is mainly distributed in finer fractions with a relatively higher de nsity range of 1.59 2.28 g/cm 3 S un and Barlaz (2015 ) tested on three samples of CDD fines and found the sulfate content to be 16.3% 24.0%.

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23 Although previous research on chemicals in CDD fines has been performed, little research has been conducted on tr ace chemicals in different size fractions In this research, the distribution of problematic chemical s in CDD fines of different size fractions which distinguished CDD fines particles roughly into gravel size material, sandy size m aterial and silty size m aterial, was examined with a goal of assessing the potential for targ et size fractionation to produce recycled products (e.g., fill material) posing less risk. Samples of CDD fines from across the US were collected, separated into distinct size fractions, and analyzed for several different constituents. Chemicals focused upon after screening include arsenic, lead, PAH and sulfate because these chemicals were most commonly found to exceed risk thresholds or generated bad odor in the past 2. 2 Methods and Ma terials 2. 2. 1 Experimental Approach CDD debris fines were collected and shipped from 12 recycling facilities distributed throughout the United States; fourteen samples were provided in total. Table 2 1 shows the original region for each sample. Each facili ty was provided directions for collecting and transporting the samples. Composite samples at each facility were obtained by taking two full shovel scoops from 20 subsample locations on the CDD fines stockpiles. The top 150 mm of fines was removed at each s ubsample location before obtaining individual subsamples. The 40 subsamples were then thoroughly mixed on a tarp, and placed into two 19 L HDPE buckets. The se buckets were shipped to the laboratory for analysis. Before analysis, each composite sample was e mptied onto a tarp and mixed again to promote sample homogeneity. Four kilograms of each composite sample were air dried

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24 overnight and screened using 25 mm, 19 mm, 4.8 mm, 0.84 mm and 0.30 mm screens to create the following sample fractions: Greater than 2 5mm fraction 25mm to 19mm fraction 19mm to 4.8mm fraction 4.8mm to 0.84mm fraction 0.84mm to 0.30mm fraction Less than 0.30mm fraction These fractions were first weighed to determine the distribution of sample mass. The greater than 25mm and the 25mm to 19 mm fractions were visually characterized to determine material composition, but were not analyzed for chemical composition. The remaining sample fractions fall within the size range most commonly referred to as CDD fines and were analyzed for total heavy m etal concentration (mg/kg), total PAH concentration (mg/kg), gypsum content (%), and volatile solids content (%). 2.2 .2 Fines Processing and Characterization The material composition of the greater than 25mm and the 25mm to 19mm fractions was determined by manually sorting these fractions into recognizable components and then weighing each component. Component categories included asphalt, gypsum, concrete, paper, wood, glass, cotton, plastics and metal. The 19mm to 4.8mm, 4.8mm to 0.84mm, 0.84mm to 0.30mm, and less than 0.30mm fractions, which can be classified as gravel size (19mm to 4.8mm), sandy size (4.8mm to 0.84mm), and silty sand size (0.84mm to 0.30mm, less than 0.30mm), were analyzed as described below:

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25 Heavy metal concentrations were determined us ing EPA Method 3050B (US EPA, 1996). This method involved digesting 1 g of dry sample with repeated additions of HNO 3 H 2 O 2 and HCl. The digestate was then filtered and residues were rinsed with nanopure water. After digestion, the samples were analyzed wi th with iCAP 6200 of Inductively coupled plasma atomic emission spectroscopy (ICP AES). Targeted heavy metals included aluminum, arsenic, chromium, copper, lead, nickel and zinc. Heavy metal analysis for each sample fraction was conducted in triplicate. Fo r quality control purposes, a blank, blank spike and matrix spike were used. PAH concentrations were analyzed using a process involving ultrasonic extraction, cleanup and Gas chromatography mass spectrometry (GC/MS) analysis following EPA Method 3550C (US EPA, 2015). Acetone and n hexane were used as the extraction solutions, with 5 g of dry sample were mixed with a 1:1 (v/v) 10 ml of acetone/ n hexane. Ultrasonic extraction was applied to the mixture for 15 min, and the sample was then centrifuged at 2000 rpm under 20 C for 10 min. The resulting extract was siphoned out with a glass pipette into a glass round bottom flask. This extraction step was repeated twice. The combined extracts were evaporated to near dryness using a rotary evaporator. Following ext raction, the solvent extracts were cleaned using a column filled with anhydrous sodium sulfate/ silica gel/ florisil to remove water and any color that was possibly present in the extract. The concentrated extract was washed using 100 mL n hexane through t he column. The cleaned samples were then evaporated to near dryness and concentrated to 1 mL with n hexane. Surrogate chemicals were added to every other sample before extraction. Concentrated samples were then stored at 4 C before analysis. One microlit er of the concentrated sample was analyzed by GC MS equipped with a Finnigan Trace Ultra of Gas Chromatography and a Finnigan Trace DSQ of Mass Spectrometry.

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26 The GC column was 30 m 0.25 mm i.d. with a was set at 320 C, the ion source was set at 250 C and the transfer line was set at 300 C. The initial oven temperature was set at 60 C for 1 min, then ramped to 120 C at 25 C /min, then ramped to 160 C a t 10 C /min, and then ramped to 330 C at 5 C /min with a 1 min final hold time. The helium carrier gas was held at a constant rate of 0.3 mL/min and the analysis was in single ion monitoring (SIM) mode. A blank sample and a surrogate standard mixture we re used for quality control. PAH analysis for every sample was conducted in duplicate. Individual PAH concentrations, as well as a total BaP equivalent concentration were determined. The equivalent BaP concentration was calculated as follows : (2 1) From which, C1 is Benzo[a]anthracene concentration, C2 is Chrysene concentration, C3 is Benzo[b]fluoranthene concentration, C4 is Benzo[k]fluora nthene concentration, C5 is Benzo[a]pyrene concentration, C6 is Indeno[1,2,3 cd]pyrene concentration and C7 is Dibenz[a,h]anthracene concentration. The gypsum content was analyzed using a modified method developed by Musson et al. ( 2008). For each sam ple f raction, 50 g of sample were ground with pestle into less than 0.5 cm in size, 10 g of sample were transferred into a 200 mL HDPE bottle, and 200 mL of nanopure water was placed into the bottle. The bottle was then rotated at 30 rpm for 30 min. After the b ottles were removed from the rotator, the particulate matter in the solution was allowed to settle for 30 min. Half of the extract was used to measure conductivity and the rest of the extract was pressure filtered using an acid washed TCLP filter of 45 mm measured c /cm, the filtering solution was used for sulfate

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27 however, the filter was removed and returned to the bottle with any solid on it, and the extraction process was repeated. Sulfate extracts were analyzed using ICS 1500 of Ion Chromatography. Each sample fraction was measured in duplicate. The total gypsum content was calculated based on the sum of sulfate content of each e xtraction step. The equation is presented below: (2 2) Where n is the number of extractions, Ci is the sulfate concentration in each extraction step ; 0.001991 is the conversion constant assuming a L/S of 10/1, and a 90%/10% of gypsum/ paper composition f or gypsum wallboard. Volatile solids content was measured in duplicate according to EPA Method 1684 (US EPA, 2011). It involves weighing 20 g of sample and placing it in an oven at 105 C overnight, and finally placing the oven dried samples into the muffl e furnace at 550 C for 4 hours. The VS content was then calculated based on the weight loss before and after putting into the furnace. 2. 2. 3 Mass Balance Calculations Results presented in the next section are calculated as cumulative percentage s of total mass for each measured parameter. Thus, the mass of a chemical obtained on one fraction is divided by the total mass of this chemical from all four fractions (4.8 19 mm, 0.84 4.8 mm, 0.30 0.84 mm and < 0.30 mm). 2. 3 Results and Discussion 2. 3.1 Mass Distri bution and Composition Study While not considered CDD fines for the purposes of this study, the greater than 25mm and 25mm 19mm fractions which comprised 14% and 10% of the total CDD mass as in Figure 1(a), were visually characterized to determine the lik ely source of the chemical constituents in the CDD fines (size fractions below the 19mm screen). The results of this characterization are

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28 shown in Figure A 8 and Figure 2 1(b). It can be concluded that concrete was the most abundant component in these size fractions; on average, it was 43% to 46% of the mass of the greater than 25mm and 25mm 19mm fractions, respectively. Wood and asphalt were the second and third largest components, with 20.1% and 15.2% in the greater than 25mm and 25mm 19mm fractions, resp ectively. The relatively high percentage of wood here correlated to the high VS content in 4.8mm 0.84mm and 19mm 4.8mm fractions, which comprise 50% to 80% of total volatile solid mass as present in Figure 2 3. The distribution of sample mass in each of t he CDD fines fractions (19mm to 4.8mm, 4.8mm to 0.84mm, 0.84mm to 0.30mm, and less than 0.30mm fractions) is shown in Table B 2 and Figure 2 2. It can be concluded that 50% to 90% of the sample mass reside in the gravel and sandy CDD fines size (19mm 4.8mm and 4.8mm 0.84mm) 2. 3.2 VS Content As observed from Table 2, the overall average VS content of the CDD fines (< 19 mm) average VS mass for the four size fractions in Table B 3 shows that the two larger size fractions (containing 44.2 g and 57.1 g VS mass respectively) tend to have higher organic materials than the two smaller size fractions (containing 16.5 g and 11.5 g VS mass respectively). Volatile solids mass i n cumulative percentage of different size fractions for each sample were shown in Figure 2 3. More than half of the VS mass was obtained on the two larger size opening sieves and each of the two smaller size fractions only comprised less than 30% of total VS mass. The mass of VS primarily occurred in larger size fractions might be explained by the presence of some pieces of wood found in larger particle size samples as well as the relatively larger amount of sample mass was in larger size fractions

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29 2. 3.3 Total Heavy Metal Eight heavy m etals of concerns were targeted for analysis, but As and Pb were focused upon because they are frequently closest to risk thresholds It can be seen from Table B 4 that the average arsenic concentrations of all 14 samples r anged from 2.05 mg/kg to 11.53 mg/kg; and from Table B 5 the average lead concentrations of all 14 samples ranged from 5.57 mg/kg to 1905 mg/kg. T he average a rse nic concentrations of each of the four size fraction s, as seen in Table 2 3, ranged from 5.17 mg/kg to 5.62 mg/kg (weighted average of 5.62 mg/kg) and the average l ead concentrations ranged from 339 mg/kg to 452 mg/kg ( weighted average of 361 mg/kg). This indicates most arsenic concentrations were evenly distributed throughout the sample, although a few were found to be slightly lower in gravel size materials (19mm 4.8mm ). Compared with the study by Chen et al. (2001), where found the average arsenic soil upper baseline concentration was 7.02 mg/kg, the arsenic concentration detected fell in this ra nge. While Figure 2 4 indicates arsenic in half samples res ide in larger size fractions, a rsenic concentrations are generally evenly distributed, which d id not follow the trend observed with VS (greatest content in the gravel size fraction ) This further proved the statement that the arsenic present in the CDD fines was likely not derived from CCA treated wood, but more likely from naturally occurring concentrations found in the soils. I n terms of lead from Figure 2 5 less than 20% of its total mass reside d in the largest particle size range with only one ex ception (Sample F) A ccording to Table 2 3, if removing s ample F, there is a dramatic drop in Pb concentration as the sample size becoming larger (83.5 mg/kg in the finest fraction and 424 mg/kg in the coarse st fraction). T he abnormally high lead concentration in the largest size fraction of Sample F might be a result of a piece of debris coated with lead Research of Turner et al. (2016) on exterior paints showed that the average lead concentration was 29300 mg/kg, which proves the

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30 assumption for the high lead concentration of Sample F. But overall, it can be concluded that lead wa s concentrated in the fines. Figure A 2 to A 7 shows cumulative percentage s of mass for Al, Cd, Cr, Cu, Ni and Zn. For most samples Al and Cr distribute evenly, with each fraction comprised 20% to 25% of the chemical mass. While the percentage mass of Zn, Cd Ni and Cu in these samples were much higher in smaller size fraction samples. 2. 3.4 Total PAH Overall, nineteen different PAHs were detected, with all of the detected non carcinogenic PAHs below PAH risk thresholds (FSCTL) and some of t he detected carcinogenic PAHs (equates to BaP equivalent PAH) above risk thresholds BaP equivalent total PAH was used to represent carcinogenic P AHs to a comparable amount of BaP and add the seven carcinogenic PAHs together into a BaP equivalent total PAH value. Table 2 4 shows the result of BaP equivalent total PAH concentrations in the four si ze fractions of the 14 samples. From the table, the su m of weighted average BaP equivalent concentrations for the 11 detected samples ranged from 0.01 m g/kg to 4.92 m g/kg Table 2 4 also indicates that, w i t h the exception of s ample K, the highest total PAH concentr ation occurred either in the finest fraction ( six out of eleven samples) or the 0.84 mm fraction (five out of eleven samples) which is the sandy size fraction tested Figure 2 6 presents the cumulative percentage mass of BaP equivalent total PAHs detected in each size fraction All samples, except S ample K, ha d less than 10% BaP equivalent total PAHs in the g ravel size fraction This supported the finding of Jang and Townsend (2001) that most of the PAHs were presented in the finer materials and they might from roadside soils that absorb ed vehicle emissions or small pieces of asphalt containing materials

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31 For example, research of Banger et al. (2010) found the highest PAH concentration in soil was 2.36 mg/kg and research of Legret et al. (2005) detected the total PAH concentration for new conventional asphalt and RAP were 4.3 mg/kg and 1.8 mg/kg, respectively. These PAH concentrations were all within the detected range as described for the CDD fines. This means the PAH sources in CDD fines could be any of these materials. 2. 3.5 Sulfate T able B 6 illustrates the gypsum content in different size fractions of the 14 samples. The gypsum content in each size fraction ranged from 0.29% to 29.6%. Higher gypsum content equates to higher sulfate concentrations in samples. Figure 2 7 shows the cumu lative percentage mass of sulfate in different si ze fractions of the 14 samples. It can be concluded that all the g ravel size fraction comprised less than 30% of all sulfate concentration, with few samples having relatively evenly distributed sulfate concentration (Sample E, Sample K, Sample J and Sample M). The relatively higher percentage of sulfate in the coarse fraction could be derived from the occurrence of some pieces of gypsum drywall due to different processing techniques utilized at d ifferent recycling facilities. Overall, sulfate ten d to reside in finer fractions. 2. 3.6 Risk Assessment and Mitigation Approach B ased on the di scussions above lead, PAH and sulfate tend to reside in the finer siz e fractions of CDD fines. T he finer fr actions of CDD fines tend to have lower sample mass (Figure 2 2) but comprise a higher percentage of these chemicals while only arsenic distributed fairly evenly throughout those samples. Figure 2 8 (a) (d) present s the weighted average concentrations of t he four chemicals (arsenic lead BaP equivalent total PAH and sulfate) after removing several finer size fractions. It can be observed that the chemical concentrations in most samples decreased a s sandy materials from the samples were removed except in some sam ple s

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32 having occasionally high concentrations in gr av el s iz e ma te ri al s ( particle r ange of 4.8 mm 19 mm ) such as lead in Sample F) target percentage reductions were chosen when removing certain particl e size ranges Table 2 5 presents how many samples would be reduced by 25%, 50% and 75% by removing particle size ranges of less than 4.8 mm (removing sand size and silty sand size materials) and less than 0.84 mm (silty sand size materials). It can be obse rved that removing silty a lot for chemical reductions compared to removing both sand size and silty sand materials. If considering more number of sample reduction and more reduction rate, removing both sand size and silty sand m aterials (particles of less than 4.8 mm) to get a 50% reduction might be the most desirable option. Therefore, it can be hypothesized that by removing sandy and silty materials, these chemical concentrations can be reduced to some extent. 2.4 Con clusion In the four size fractions below 19 mm, most of the sample mass resides in the larger size fractions, where a greater VS content was measured as well. Aluminum, arsenic and chromium concentrations resided almost evenly in each of the four size fractions. Lea d, cadmium, nickel and copper tended to have higher concentrations in the smaller size fractions. In terms of BaP equivalent total extractable PAH, the highest concentrations mostly occurred in sandy and silty sand size materials. If the sandy and silty sa nd size fractions were removed, the remaining largest size fraction only contained less than 10% of BaP equivalent total extractable PAHs of each sample. When compared with regulatory soil cleanup target levels as presented in Table B 13, more samples had PAH concentrations below risk thresholds as their size became larger. The same conclusion was also valid for sulfate as more than 70% of the present sulfate resided in the three

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33 finer fractions. It can therefore be hypothesized that screening out sandy and silty sand size materials by either a washing process or mechanically shaking process might help to result in reduced concentrations of lead, sulfate and BaP equivalent total PAH. For arsenic and some other heavy metals, the concentrations are evenly dist ributed, thus removing the finer fractions would likely not help reduce these concentrations significantly

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34 Table 2 1. Sample letter s with corresponding r egions Sample Letter Region of US A Pacific B Pacific C Pacific D South Atlantic E Pacific F New England G East North Central H East North Central I Mid Atlantic J East North Central K South Atlantic L West South Central M South Atlantic N West North Central Table 2 2. VS c ontent measured on different sieve sizes for the 14 samples in duplicate (%) Sieve Size A B C D E F G H I J K L M N average 4.8 19mm 38.6 9.71 48.7 15.9 22.0 26.3 18.0 24.8 12.2 12.9 4.60 6.39 15.0 29.5 20.3 0.84 4.8mm 19.4 15.2 48.5 11.1 21.4 26.5 25.8 18.5 7.55 19.8 18.2 11.2 22.8 17.8 20.3 0.30 0.84mm 12.4 10.8 42.6 6.79 22.2 9.62 10.0 9.06 8.25 13.7 7.84 1.87 14.8 13.7 13.1 <0.3mm 10.4 14.1 35.4 4.05 13.6 7.55 11.3 9.00 10.1 16.7 10.8 5.61 11.2 14.3 12.4 Total weighted average percentage 24.6 13.7 46.3 10.4 21.0 16.7 19.1 17.6 9.1 15.2 11.2 6.7 17.4 22.8 18.0 Table 2 3. Average As and Pb concentrations reside in the four si ze fractions for all 14 samples (mg/kg). Sieve Size As Pb Pb without Sample F < 0.30mm 5.48 416 424 0.30 0.84mm 5.54 434 396 0.84 4.8mm 5.62 339 262 4.8 19mm 5.17 452 83.5 Total weigh ted average 5.62 361 242 Average Standard Deviation 1.27 4.32 3.62

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35 Table 2 4 BaP equivalent total PAHs obtained on different size f ractions and total weighted average BaP equivalent total PAH concentrations for all 14 samples in duplicate (m g/kg) Samp les 4.8 mm sieve 0.84 mm sieve 0.30 mm sieve < 0.30 mm sieve Weighted average A < 0.0 1 < 0.0 1 < 0.0 1 < 0.0 1 < 0.01 B 0.04 0.01 0.06 0.35 0.04 C 0.06 0. 29 0. 16 0. 1 5 0.17 D 0.06 0. 40 1 .12 3 19 0.86 E < 0.01 < 0.0 1 0.02 0.02 0.01 F < 0.01 < 0.0 1 < 0.0 1 < 0.0 1 < 0.01 G 1 .09 4 .59 3 .30 4 .07 3.22 H 1 .85 5 04 7 .79 8 11 4.92 I 0.12 0.54 0. 37 0. 98 0.51 J 0.02 0.44 0.23 0.32 0.19 K 0.69 0.27 0. 15 0. 25 0.33 L < 0.0 1 < 0.0 1 < 0.0 1 < 0.0 1 < 0.01 M < 0.0 1 0.03 0.52 0.46 0.17 N < 0.01 0.15 0.03 0.03 0.04 *Av erage recovery rate: TE (83.2%), ME (82.3%), PE (78.0 %) Table 2 5 Number of samples chemical concentrations reduced by 25%, 50%, 75% when removing particle size of less than 4.8 mm and 0.84 mm Examined CDD fines fractions Elements 25 % reduction 50 % redu ction 75 % reduction Remove particles of less than 4.8 mm PAH 9 9 6 Sulfate 7 5 1 As 6 1 1 Pb 12 8 7 Remove particles of less than 0.84 mm PAH 5 3 2 Sulfate 1 0 0 As 1 0 0 Pb 9 9 0

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36 Figure 2 1 Average percentage mass of each size fraction (a) and cumulative percentage of CDD fine components (b) 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 19-25 mm > 25-mm Cummulative Percentage of CDD Fines Composition Steel Plastics Cotton Glass Wood Paper Concrete Gypsum Asphalt (b) >25mm 14% 19 25mm 10% 4.8 19mm 21% 0.84 4.8mm 29% 0.30 0.84mm 15% < 0.30mm 11% ( a )

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37 Figure 2 2 Comparison of mass distribution as a function of particle size for 14 samples in duplicate Figure 2 3 Comparison of VS mass distribution as a function of par ticle size for 14 samples in duplicate 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage mass (%) Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of VS concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm <0.30mm

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38 Figure 2 4 Comparison of As concentration mass distribution as a function of particle size for 14 samples in triplicate Figure 2 5 Comparison of Pb concentration mass distribution as a function of particle size for 14 samples in triplicate 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of As concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of Pb concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm

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39 Figure 2 6 BaP equivalent total PAH mass distribution as a function of particle size for 11 detected samples in duplicate Figure 2 7 Sulfate concentration mass distribution as a function of particle size for 14 sample s in duplicate 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% B C D E G H I J K M N Cummulative Percentage of BaP Equivaleng Total PAH concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm <0.30mm 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of Sulfate concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm <0.30mm

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40 Figure 2 8. Risk assessment for As (a), Pb (b), PAH (c) and sulfate (d) when continuously removing each of the finer size fraction 0 2 4 6 8 10 12 14 16 A B C D E F G H I J K L M N As concentrations in different cumulative size fractions (mg/kg) 0-19mm 0.84-19mm 4.76-19mm 0 1,000 2,000 3,000 4,000 5,000 6,000 A B C D E F G H I J K L M N Pb concentrations in different cumulative size fractions (mg/kg) 0-19mm 0.84-19mm 4.76-19mm (b) (a)

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41 Figure 2 8. (continued) 0.0 1.0 2.0 3.0 4.0 5.0 6.0 A B C D E F G H I J K L M N BaP equivalent total PAH concentrations in different cumulative size fractions ( m g/kg) 0-19mm 0.84-19mm 4.76-19mm (c) 0 50,000 100,000 150,000 200,000 250,000 A B C D E F G H I J K L M N Sulfate concentrations in different cumulative size fractions (mg/kg) 0-19mm 0.84-19mm 4.76-19mm (d)

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42 CHAPTER 3 CONTRIBUTION OF ASPHALT PRODUCTS TO EXTRACTABLE AND BIOACCESSIBLE POLYCYLIC AROMATIC HYDROCARBONS IN SOIL 3.1 Introduction and Background Polycyclic Aromatic Hydrocarbons (PAH s ) have been associated with adverse health effects and are chemicals of concern when released into the environment. High ring PAH s (4 6 aromatic rings) are known to be carcinogenic and can be persistent in the environment while low ring PAHs (2 3 aromatic rings) are classified as toxic comp ounds (Fernandes et al., 2009). Polycyclic aromatic hydrocarbons (PAH s ) are frequently encounter ed when characterizing urban soils as part of remediation plan risk assessments ( Man et al., 2013; Hussar et al., 2012). Similarly, PAHs have been documented when assessing potential risks of soil like waste materials proposed for beneficial use (Allan et al., 2016; Azah et al., 2015). In addition to point source contributions from specific industrial activities or chemical spills, PAHs in urban soils also occur because of common anthropogenic contributions such a s fossil fuel combustion and vehicle emis sions (Abdel Shafy and Mansour, 2016; Lee and Vu, 2010). As PAHs are known to exist in petroleum products, asphalt containing materials in roadway pavement and roofing systems have been cited as potential source s of soil PAHs, either from PAH compounds le aching from these materials or directly from small pieces of these materials contained with in the soil samples themselves (Brandt and Groot, 2001; Ruby, 2016 ) Asphalt products are manufactured using bitumen, a material produced in petroleum refineries usi ng a crude oil distillation process. The process involves heating the crude oil to temperatures between 300 in a vacuum, which removes a majority of PAHs from the product. However, PAHs of very heavy molecular weight remain at the bottom of the d istillation column in the bitumen. When asphalt is heated, such as with the manufacture of hot mix asphalt pavement, additional PAH volatilization may occur (US EPA, 2000). Though low in aqueous

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43 solutions, PAH can migrate from asphalt products when exposed to water, and thus migrate into the environment from rainwater contact. Several studies have been conducted to examine PAH concentrations (total and leachable) from asphalt containing materials. Bran tley and Townsend (1999) analyzed PAH concentrations in re cycled asphalt pavement (RAP) leachate obtained from both batch and column leaching tests and measured no concentrations of PAH above the detection limit. A study on asphalt leaching by Brandt and Groot ( 2001) detected only PAH compounds with 4 rings or less, with all concentrations below regulatory limits for surface water. Tang (2006) measured PAH concentrations on 100 % petroleum oil based products, such as hot mix asphalt and targeted PAHs with more than two rings tend to have low concentrations, with phen anthrene having the highest concentration at 12.9 mg/L. Fernandes et al. ( 2009) analyzed PAH content in asphalt binder and observed that 15 out of 16 EPA priority PAHs were detected, with average concentrations of < 10 mg/kg for l ow ring PAH compounds and 10.2 27.2 mg/kg for high ring PAH compounds. Azah (2011) also conducted a batch leaching test that measured PAH contaminants in RAP leachate, where eight PAH were det ected with concentrations ranging from 68.0 ng/L to 735 ng/L. Benzo[a]anthracene and benzo[b]fluoranthene were found to exceed their corresponding GCTL (50 ng/L), at 6.5 times and 2.1 times higher respectively. From the research of Azah (2015), high PAH concentrations were found to be higher in finer fractions of str eet sweeping, with the highest total PAH concentration of approximately 21 mg/kg, suggesting the PAH source was not from piece s of asphalt. Diagnostic ratios can aid in distinguish ing potential sources of PAH in media, and thus may be useful for assessing whether the source s of PAH in disposed asphalt products are from the products themselves or from contaminants that have come into contact with the products

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44 during their service life. This method evaluates the ratios of PAH concentrations with similar molec ular weights and assumes PAH isomers degrade at a similar rate and maintain the same properties, thus preserving the relative proportion of different PAH compounds (Biache et al., 2014) Among all of the commonly used diagnostic ratios, the ratio of anthracene to anthracene plus phenanthrene is most widely used (Katsoyiannis et al., 2007) Based on each diagnostic ratio within a defined range, P AH source can be classified as e ither petrogenic or pyrogenic. Some ratios can further classify whether th e source is from fuel combustion (e.g. coal combustion versus wood combustion ) or whether it is traffic or non traffic related (Allan et al., 2016; Biache et al., 2014) For example, a ratio of anthracene/(anthracene + phenanthrene) greater than 0.1 is generally indicative of pyrogenic and less than 0.1 is petrogenic Another issue of importance when assessing the risk posed by PAH resulting from asphalt products is the degree to which the PAH compounds are biologicall y available. Bioaccessibility is defined as the physical solubility of a chemical at the portal of entry into the animal body (Ruby et al., 2016). Particle size s of less than 250 m have been the most commonly used for PAH bioaccessibility studies (Li et a l., 2015; Cui et al., 2016). A common method to test bioaccessibility is the physiologically based extraction test (PBET), which includes different methods such as Tenax, solid phase micro extractions (SPME), and polyoxymethylene solid p hase extraction (PO M SPE). In vitro studies like these have been developed to mimic gastrointestinal system condition s and provide a close prediction of bioavailable PAH concentration according to the amount of PAHs accumulated in mice or earthworms (Gomez eyles et al., 2012) M ild solvent extraction is a new method that uses butanol or cyclodextrin and has been found to result in similar extraction of PAH compounds as compared to animal validation test s (Gomez eyles et al. 2012; Ruby et al., 2016) PAH

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45 bioaccessibility of asphalt products has not been reported, though some research on PAH bioaccessibility from soil impacted by roads has been discussed. Ruby et al. ( 2016) commented that oral bioavailability might be overestimated when the benzo[a]pyrene concentra tion is high, up to tens to thousands mg/kg while aging or w eathering of soils may decrease bioavailability of PAH concentrations. In this paper, we assess the degree to which asphalt products contained in soil contribute to measurable PAH concentrations. As soil PAH concentrations are measured by first extracting soil samples using an organic solvent, samples of soil mixed with different amounts of various asphalt products (e.g., shingles, bituminous cement) were solvent extracted using conventional proce dures, and if measurable PAHs were observed, results were compared to risk based thresholds as an indication of possible si gnificance. Diagnostic ratios were used to identify the p otential source of detected PAHs To further evaluate the risk posed by PAH as a result of asphalt materials in soil, the bioaccessibility of the soil asphalt mixtures was measured using an n butanol extraction procedure and PAH concentrations were then compared to risk based clean soil thresholds. 3. 2 Method and Materials 3. 2.1 E xperimental Approach Eleven different asphalt products, including three new asphalt shingles, three used asphalt shingles (with lifespans between 12 15 years), two fresh bitumen sources two RAP sources (reclaimed asphalt pavement) and one new asphalt pav ement source were obtained. A detailed description of these materials is summarized in Table 3 1. Except for the two bitumen samples the other samples were size reduced to less than 0.5 cm and were mixed with pure sand at asphalt product percentages of 1 %, 10% and 100%. For the two bitumen samples, the three sample percentages were obtained by heating the mixed samples at approximately 120 C while

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46 continually stirring and mixing them until homogenous All samples were analyzed for total extractable PAH a nd bioaccessible PAH concentr ations, and PAH diagnostic ratios were examined. 3. 2.2 Sample Pre treatment All materials, except bitumen, were size reduced to less than 0.5 cm upon arrival due to the limitation of material to make the particle size down to l ess than 250 m. A sphalt shingle samples were size reduced using scissor s and asphalt pavement samples (i ncluding RAP) were size reduced using a hammer. Each of these size reduced materials was mixed with 40 100 mesh pure sand purchased from Acros Organi cs in different percentages by mass to obtain a 100 g composite sample. The composite sample s were then shaken and stirred with a clean glass rod to promote homogeneity. Each mixed sample was placed in a clean glass jar. Due to the viscous property of bitu men, a composite sample could not be c reated to reach the desired homogeneity through size reduction alone Therefore, each bitumen sample and the desired mass of sand were weighed according to the three target percentages and placed in a beaker. The beake r was placed time to distribute the melted bitumen evenly through out the sand. The pure, 100% bitumen was heated at the same temperature and for the same durati on to ensure the sample consistency. 3. 2.3 Extraction Procedures Modified EPA M ethod 3550C (US EPA, 2007) was used fo r total extractable PAH analysis. Five g rams of sample was mixed with 10 ml of acetone/ n hexane (1:1 v/v) Ultrasonic extraction was appl ied to the mixture for 15 min, and the sample was then centrifuged at 2000 rpm under 20C for 10 min. T he extract was then siphoned out using a glass pipette into a glass round bottom flask. This extraction step was repeated twice The combined extracts we re evaporated to near dryness using a rotary evaporator. Following extraction, the solvent extracts

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47 were cleaned using a column fille d with anhydrous sodium sulfate, silica gel, and florisil. The concentrated extract was washed with 100 mL n hexane through the column. The cleaned samples were then evaporated to near dryness and concentrated to 1 mL with n hexane. The method of Gomez E yles et al. ( 2012) was used to examine PAH bioaccessibility. A 10 g size reduced sample placed in 15 mL of butanol was vorte xed for 50 s (Gomez E yles et al., 2012; Liste and Alexander, 2002; Swindell and Reid, 2006). The sample was centrifuged at 2000 rpm at 2 0 C for 5 min to separate the solid and liquid phases. The liquid phase was passed through a 0.45 m PTFE filter and th e extract was transferred to a sample vial. For quality assurance, a surrogate mixture (o Terphenyl, 6 Methylchrysene and Perylene d12) was added to every 10 samples to obtain the recovery rate, and a duplicate was used on every sample for both extraction s. 3. 2.4 Analytical Procedures One microliter of the concentrated sample for total extractable PAH was analyzed by a GC MS equipped with a Thermo Scientific Trace GC Ultra of Gas Chromatography and a Thermo S cientific DSQ2 Mass Spectrometry. The GC column was 30 m 0.25 mm i.d. within ramped t a 1 min final hold time The helium carrier gas was held at a constant rate of 0.3 mL/min and the analysis was in single ion monitoring (SIM) mode. The analytical procedure for bioaccess ible PAH was the same as total extractable PAH. For quality assurance, a blank sample and a surrogate mixture were used at the beginning of each GC MS analysis.

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48 3. 2.5 PAH Diagnostic Ratios Five diagnostic ratios of PAHs were calculated using the method of Bra ndi et al. ( 2007 ) and Katsoyiannis et al. ( 2007). If one of the two PAHs in any diagnostic ratio was not detected, this particula r diagnostic ratio was not repor ted (US EPA, 2014). The sources of PAHs in the sample were then estimated according to the d iagnostic ratios. Detailed diagnostic ratio cat egories are summarized in Figure 3 2 3. 2.6 BaP equivalent total PAH calculation Measured PAHs were further calculated for BaP equivalent total PAH since the 7 EPA designated carcinogenic PAHs are more of a co ncern to human health and BaP is present to be the most carcinogenic among them. Each of the other 6 PA H s can be multiplied by certain coefficient and obtain a value that is equivalent to BaP concentrations. Thus, the BaP equivalent total PAH concentration was calculated as follows: (3 1) From which, C1 is b enzo[a]a nthracene concentration, C2 is chrysene concentration, C3 is b enzo[b]flu oranthene concent ration, C4 is b enzo[k]fluoranthene concentration, C5 is b enzo[a]pyrene concentration, C 6 is i ndeno[1,2,3 cd] pyrene concentration and C7 is d ibenz[a,h]anthracene concentration. 3. 3 Results and Discussion 3. 3.1 Total Extractable PAHs The total extractable PA H concentrations from all 11 samples are presented in Table s 3 2 to 3 5 In terms of pure asphalt products (100%) 7 PAH compounds (naphthalene, phenanthrene, anthracene, chrysene, benzo(a)pyrene, d ibenz[a,h]ant hracene and dibenzo[a,l]pyrene) were detected in new asphalt shingles, with all concentrations less th an 0.1 mg/kg except naphthalene

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49 Among these 7 PAH compounds only d ibenz[a,h]anthracene was detected in all three types of new asphalt shingles with its concentration ranging from 0.05 mg/kg to 0.0 75 mg/kg A ged asp halt shingles were only found to posses s measurable concentrations of th ree low molecular weight PAHs (naphthalene, acenaphthene and phenanthrene), with p henanthrene only detected in AAS1. Compared to new shingles, the aged shingles conta ined low er molecular weight PAH compounds with concentrations approximately three to four magnitude s higher than the new shingles. For example, phenanthrene was detected at 0.06 mg/kg in pure NAS1 and 369.3 mg/kg in pure AAS1. The elevated concentration f or low molecular weight PAH might be due to the long term exposure of aged asphalt shingles. But the non detection of high molecular weight PAH in aged shingles also reveals that weathering may reduc e the amount of high ring PAH pre sent. Previous research on b enzo[a]pyrene absorption from coal tar contaminated soil also ind icated a two fold reduction on b enzo[a]pyrene after 110 days of weathering (Ruby, 2016). In terms of RAP, all 10 PAHs detected (except naphthalene) were below 100 mg/kg. These PAHs includ e d naphthalene, acenaphthene phenanthrene, fluoranthene, pyrene, b e nzo[a]anthrace ne, benzo[b]fluoranthene, benzo[a] pyrene, benzo[g,h,i]perylene and anthanthrene. P ure sample s of RAP2 exhibited detected PAH compounds r anging from 1.6 mg/kg (ACE) to 396 mg /kg (NA), and had more low er molecular weight PAH compounds compared to RAP1 ( PAH compounds range d f rom 3.82 mg/kg (ACE) to 55.3 mg/kg (PY) ) For new asph alt pavement and bitumen, 9 PAH compounds (except naphthalene) were detected with concentratio ns less than 50 mg/kg Detected PAHs included naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, pyrene, benzo[a]anthr acene and chrysene. The bitumen samples were found to have more low ring PAHs (ranged from 1.56 mg/kg PH to 181.8 NA in B1 and 0.29 mg /kg of PY to 7.64 mg/kg FL in B2) while the new asphalt pavem ent was detected

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50 to have few er high ring PAHs (ra nged from 1.40 mg/kg CH to 390 mg/kg NA) The relatively low PAH concentration in bitumen suggests that bitumen might hold PAHs and prevent them f rom being extracting out of its matrix The 10% and 1% asphalt product mixtures along with 100% pu re asphalt products in Table 3 2 to Table 3 5 also reveal the impact of different percentage of soils had on PAH concentrations when added to asphalt products Most PAH concentrations decreased with a decreasing percentage of asphalt products For example, benzo[a]pyrene concentrations in RAP1 decreased from 9.12 mg/kg to 0.10 mg kg while phenanthrene concentrations in NAP1 decreased from 9.85 mg/kg to 1.95 mg/ kg when asphalt percentage s dropped from 100% to 1% (t he same trend for the other PAHs (Ruby, 2016) on benzo[a]pyrene concentrations from coal tar, petroleum products, and other PAH sourc es of contaminated soil showed a range of 0.2 to 270 mg/kg, from which the benzo[a]pyrene results obtained here fall into approximately the same range. N aphthalene in AAS1 and acenaphthene in AAS2 tend ed to have higher concentration s in 10% mixture s than i n pure samples and phenanthrene has higher conce ntration in 1% of AAS1 than 10%; the decreasing trend for other samples is convincing. Table 3 6 shows b enzo[a]pyrene equivalent (BaP equivalent) PAH concentrations Five out of the 11 samples were detected with BaP equiv alent total PAH concentrations: NAP1, RAP1, NAS1, NAS2 and NAS3. Table B 13 shows FL SCTLs and National RSL for all detected chemicals. W hen compared to the Florida Soil Cleanup Target Levels (FSCTLs), all pure new shingles (NAS1, NAS2, NAS3 ) were below the residential FSCTL (0.1 mg/kg), pure new asphalt pavement (NAP1) was below commercial/industrial FSCTL (0.7 mg/kg) while 100% RAP1 was above the commercial/industrial FSCTL. From the prospective of lower asphalt percentages

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51 (10% and 1%), e ven with the 10% sample RAP1 was still above the com mercial/industrial FSCTL and its 1% sample wa s above the residential FSCTL. For the other four samples, the BaP equivalent total PAH were decreas ed to below the residential FSCTL. In terms of EPA Regiona l Screening Level (RSL), only NAP1 with 1% asphalt materials did not exceed the residential RSL (0.016 mg/kg) and only RAP1 of 100% and 10% asphalt materials exceeded industrial RSL (0.29 mg/kg). If comparing non carcinogenic PAH concentrations with the r isk th resholds presented in Table B 13 6 out of the 11 and 3 out of 11 pure asphalt products had naphthalene exceeding residential and industrial/ commercial FL SCTL, respectively; 7 out of 11 and 5 out of 11 exceeding residential and industrial/ commerci al RSL, respectively. 3. 3.2 Diagnostic Ratios Diagnostic ratios for 5 pairs of PAH of similar molecular weight were used to identify whether the source of PAH is derived from incomplete combustion (pyrogenic) or the petroleum product ( petrogenic) These ra tios were only de termined on pure asphalt product samples. But not all asphalt products were detected to have all the ratios and not all ratios were available for these asphalt products. Table 3 8 presents the result of the diagnostic ratios. The classific ation s of these diagnostic ratios were identified based on past studies ( Bra et al., 2007; Colombo et al., 1989; Yunker et al., 2002 ; Azah et al., 2015 ) Past diagnostic ratio research conducted by Azah (2015) used this method and indicated that the PAH source from roadway and stormwater system main tenance residues were from pyrogenic activities, such as fuel combustion. It is assumed that PAH sources of new asphalt products are mainly petrogenic. Diagnostic ratio results are presented in Table 3 7. NAP1 and B1 were detected for Ant /(Ant+Phe) ratio; NAP1 was detected for BaA/( BaA+Chr) ratio ; RAP1, RAP2 and NAP1 were detected for Flt/(Flt+Pyr) ratio, and RAP1 was detected for BaP/BPE ratio Ac cording to

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52 Ant/(Ant+Phe) ratio, PAH from NAP1 and B1 were d erived from pyrogenic sources. PAH in NAP1 was generated from p yrogenic source (e.g., grass/ wood/ coal combustion) in terms of BaA/(BaA+Chr) ratio Based on Flt/(Flt+Pyr) ratio, PAH in RAP1 and RAP2 were derived from petrogenic sources, while PAH in NAP1 was derived from pyrogenic source (e.g., grass/ wood/ coal combustion) Sources of PAH in RAP1 was assumed to come from traffic source in terms of BaP/BPE ratio Diagnostic ratios indi cate that PAH in RAP 1 might be a combination of petrogenic and pyrogenic sources while the PAH source for RAP2 might be petrogenic. This result seems reasonable for the RAP samples since the material came from a roadway that was in service and exposed to vehicle exhaust for many years. The result from NAP1 as pyrogenic was unexpected, but may be explained by the fact that the RAP had been stockpiled by a busy road for several days and may have been exposed to vehicle exhaust. PAH source of B1 was indicated as pyrogenic, for which the PAH might be derived from the bitumen production process since a sphalt products contain organic carbons and can form PAH when high temperature is applied. Although asphalt products are believed to be mainly derived from petrogenic sources, Biache et al. (2014) also determined the diagnostic ratios for aged coal tar to have a mixed zone of petrogenic and combustion sources. It was suggested that diagnostic ratios should be used with caution since the ratios can be dramatically changed during the process of transportation or other possible influence from storage and pre treatment. Since few PAHs were detected in the 11 asphalt products, the number of diagnostic ratios for each sample is limited. Therefore, the source indicators concluded here may need other critical validation 3. 3.3 PAH Bioaccessibility The bioaccessibility of e ach asphalt product was measured for the differen t PAH compounds calculated by dividing the bioaccessible concentratio ns by the total extractable PAH

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53 concentrations. Figure 3 1 presents the average PAH bi oaccessibility for each asphalt containing material of different percentages. The three new asphalt shingles have relatively higher PAH bioaccessibility compared to the other asphalt products. From Figure 3 1, pure new asphalt shingles had 20% to 40% bioaccessible fractions the other pure asphalt products all had less than 10% bioaccessibility from whi ch bitumen tend ed to have higher bioaccessibility of approximately 10%. P ure aged asphalt shingles tend to be more than 6 times lower than pu re new asphalt shingles; but comparing new pavement with aged pavement, the bioaccessibility of aged pavement tend to be only a little lower than new pavement. But overall, the lower bioaccessibility in aged materials correlated well with the statement from Ruby et al. (2016) that aging will reduce the bioaccessible fraction of PAH concentrations. Beside s solely lookin g at the pure samples, t he PAH bioaccessibility of 100%, 10% and 1% for each sample was either decreasing or stay ed approximately at the same level. Bioaccessibility can vary significantly due to differences in site or source. T he bioaccessibility of diffe rent types of road impacted residuals measured by Allan et al. (2016) w as less than 80% with a large variance. Johnsen et al. (2006) also measured PAH bioaccessibility of soils near motorway site, but the results indicated a bioaccessibility of less than 2 %. 3. 3. 4 Quality Control/ Quality Assurance (QA/QC) Detected concentrations for all sample duplicates showed good precision which was within 30% in most cases. The average surrogate recovery ranged between 67% to 9 0 % indicating a good accuracy. 3. 4 Conclus ion Except for RA P1 sample, which had some of its BaP equivalent PAH (100% and 10%) exceed ing industrial FL SCTL and industrial RSL relatively low BaP equivalent P AH concentrations were detected for these 11 asphalt products However, in terms of the more strict

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54 regulation of residential RSL, only NAP1 with 1% asphalt materials did not exceed the residential level. Concentrations of naphthalene of some samples also exceeded its regulatory risk thresholds. PAH concentrations in most samples decreased as the asphalt percentage decreased with the exception of a few low ring PAHs presented in aged asphalt shingles This might be due to a combination of effects such as the higher mobility of these low ring PAHs with the influence of soil matrix and the lower ab ility of the aged asphalt shingles to retain PAHs PAH bioaccessibility for all samples were determined to be less than 40%, therefore the health risk associated w ith these products might be lower than predicted based on as strict comparison to risk thresh olds. In addition, due to the few available diagnostic ratios determined in these asphalt products, caution should be taken when using it to indicate PAH sources. Therefore, the presence of a small piece of asphalt may result in low PAH concentration, but more commonly, the PAH source in soils and wastes containing asphalt products might from other sources such as fuel and vehicle emissions.

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55 Table 3 1. Description of eleven asphalt containing materials S ample ID Description NAS1 New asphalt shingle pur chased from local market NAS2 New asphalt shingle exposed outside for several days NAS3 New asphalt shingle exposed outside for several days AAS1 3 Tab Tam ko Weathered Wood aged asphalt shingle, 12 AAS2 3 Tab Tam ko Estated Grey age d asphalt shingle, 20 25 AAS3 RAP1 Reclaimed Asphalt Pavement collected from West Palm Beach, 12 RAP2 Reclaimed Asphalt Pavement collected from Tampa, 12 15 year NAP1 New asphalt pavement collected from the roadside opposite to the oaks mall, Gainesville, FL. It was dumped on the road for 1 2 weeks. B1 PG 52 28 B2 PG 67 22 Table 3 2 New asphalt shingle total extractable PAH concentrations in dupl icate (mg PAH/kg asphalt) Samples 100% 10% 1% NAS1 NAS2 NAS3 NAS1 NAS2 NAS3 NAS1 NAS2 NAS3 NA <0.028 0.073 <0.028 <0.028 0.066 <0.028 <0.028 0.066 <0.028 PH 0.060 <0.017 <0.017 0.053 <0.017 <0.017 0.020 <0.017 <0.017 ANC <0.015 <0.015 0.060 <0.015 <0 .015 0.05 <0.015 <0.015 <0.015 CH 0.053 <0.002 <0.002 0.052 <0.002 <0.002 0.050 <0.002 <0.002 BaP <0.002 0.020 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 <0.002 DhA 0.050 0.070 0.075 0.040 0.053 0.066 0.038 0.038 0.040 DlP 0.043 <0.008 <0.008 0.039 <0.0 08 <0.008 0.038 <0.008 <0.008

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56 Table 3 3 Aged asphalt shingle total extractable PAH concentrations in duplicate (mg PAH/kg asphalt) Samples 100% 10% 1% AAS1 AAS2 AAS3 AAS1 AAS2 AAS3 AAS1 AAS2 AAS3 NA 121.1 197.3 1107 709.8 88.1 64.2 29.8 <0.028 30. 2 ACE 37.9 9.49 28.4 27.2 58.2 12.6 21.0 34.1 9.90 PH 369.3 <0.017 <0.017 23.6 <0.017 <0.017 149.3 <0.017 <0.017 Table 3 4 Reclaimed asphalt shingle total extractable PAH concentrations in duplicate (mg PAH/kg asphalt) Samples 100% 10% 1% RAP1 RAP 2 RAP1 RAP2 RAP1 RAP2 NA 41.5 396.2 31.2 297.7 20.1 100.3 ACE 3.82 1.66 2.02 1.03 3.78 0.62 PH 28.5 23.5 1.64 5.12 0.30 1.71 FLU 34.4 2.13 20.5 1.22 0.23 0.64 PY 55.3 4.06 4.82 1.18 0.11 0.14 BaA 28.9 <0.016 18.3 <0.016 1.31 <0.016 BbF 38.5 <0.001 2 .20 <0.001 0.07 <0.001 BaP 9.13 <0.002 6.20 <0.002 0.10 <0.002 BP 14.7 <0.005 10.6 <0.005 <0.005 <0.005 AN 14.3 <0.008 1.21 <0.008 <0.008 <0.008 Table 3 5 New asphalt pavement & fresh bitumen total extractable PAH concentrations in duplicate (mg PA H/kg asphalt) Samples 100% 10% 1% NAP1 B1 B2 NAP1 B1 B2 NAP1 B1 B2 NA 390.1 181.8 1.35 349.4 117.3 0.70 297.1 4.38 0.13 ACE <0.036 31.43 0.85 <0.036 13.30 0.29 <0.036 2.16 <0.036 FL <0.032 <0.032 7.64 <0.032 <0.032 1.15 <0.032 <0.032 0.20 PH 9.85 1.5 6 1.14 4.63 <0.017 0.11 1.95 <0.017 <0.017 ANC 10.3 1.15 <0.015 3.59 <0.015 <0.015 0.63 <0.015 <0.015 FLU 4.87 <0.009 0.29 1.43 <0.009 0.24 0.30 <0.009 0.12 PY 3.86 <0.009 <0.009 1.43 <0.009 <0.009 0.11 <0.009 <0.009 BaA 1.92 <0.016 <0.016 0.37 <0.016 <0.016 0.10 <0.016 <0.016 CH 1.40 <0.002 <0.002 0.44 <0.002 <0.002 0.23 <0.002 <0.002

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57 Table 3 6 BaP equivalent total PAH of the 11 asphalt containing materials in duplicate BaP eq (mg/kg) 100% asphalt 10% asphalt 1% asphalt NAP1 0.19 0.04 0.01 RAP1 15.9 8.25 0.24 NAS1 0.05 0.04 0.04 NAS2 0.09 0.05 0.04 NAS3 0.08 0.07 0.04 *Average recovery rate: TE (62.1%), ME (81.0%), PE (70.3%) Table 3 7 Detected diagnostic Ratios of pure samples. Diagnostic Ratios RAP1 RAP2 NAP1 B1 Ant/(Ant+Phe) 0.51 0 .43 Flt/(Flt+Pyr) 0.38 0.34 0.56 BaA/(BaA+Chr) 0.58 BaP/BPE 0.62

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58 0% 10% 20% 30% 40% 50% NAS1 NAS2 NAS3 AAS1 AAS2 AAS3 NAP1 RAP1 RAP2 B1 B2 100% asphalt 10% asphalt 1% asphalt Figure 3 1 Average PAH Bioaccessibility of 100%, 10% & 1% asphalt products in duplicate Figure 3 2. PAH diagnostic ratios based on PAH molecular weight (Azah, 2011; Bra et al., 2007; Colombo e t al., 1989; Yunker et al., 2002)

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59 CHAPTER 4 SUMMARY AND CONCLUSION 4.1 Summary of Research This thesis provides results from two research experiments, both of which analyzed chemicals of concer n in CDD fines. Chapter 2 examines four chemicals of conce rn in CDD fines as a function of particle size fraction and assess es whether the selective screening of certain particle size range s would decrease chemical concentrations to below applicable risk thresholds Chapter 3 examines the extent to which asphalt products repr esent a potential source of PAH in CDD fines. In Chapter 2, CDD fines samples from around the US were characterized by first screening off CDD materials above a 19 mm sieve and then conducting a composition study of this larger fraction ( concr ete, wood and asphalt we re the three main components present in larger than 19 mm CDD fines fraction ) In the four size fractions below 19 mm, most of the sample mass reside s in the larger size fractions where a greater VS content was measured as well A l uminum, a rsenic and chromium concentrations were distributed almost ev enly in e ach of the four size fractions. L ead, cadmium, nickel and copper tended to have higher concentrations in the smaller s ize fractions. In terms of BaP e quivalent total extractable PAH the highest concentration s could also occur in the s andy size materials ( 0.84 4.8 mm ) If the three finer size fractions were removed the remaining g ravel size materials only contained less than 10% of the BaP equival ent total extractable PAHs of each sample. When compared with regulatory soil cleanup target levels, more samples had PAH concentrations below risk thresholds as their size became larger. The same conclusion was also valid for sulfate as more than 70% of t he present sulfate resided in the three finer fractions. I t can therefore be hypothesized that screening out particle size s of less than 0.84 mm would result in reduced

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60 concentrations of lead sulfate and BaP eq uivalent total PAH For arsenic and some oth er heavy metals the concentrations are evenly distributed ; thus removing the finer fractions would likely not help reduce concentrations significantly. In Chapter 3, most asphalt product samples with except ion of one sample of recycled asphalt pave ment were found to have low (or non detectable) concentrations of PAH compared to risk threshold s Asphalt products may not be a significant source of PAH in CDD fines as often hypothesized. PAH bioaccessibility conducted using mild solvent extraction met hod showed relatively low bioaccessible fractions (< 40%) Available diagnostic ratios indicate d that the PAH source s w ere not only petrogenic, but also pyrogenic. 4.2 Specific Observations Concrete, asphalt and wood comprised the largest components of CDD fines of greater than 19 mm Arsenic tend ed to be evenly distributed throughout CDD fines, while Pb, BaP equivalent PAH and sulfate tend ed to reside more in the finer size fractions Screening out particle size s of less than 4.8 mm may reduce Pb, BaP equi valent PAH and sulfat e concentrations in CDD fines possibly to below risk threshold s BaP equivalent PAH concentrations of the 11 asphalt products indicated that only one RAP sample exceeded Florida risk thresholds. Naphthalene, a non carcinogenic PAH, ex ceed ed the Florida SCTL and the EPA RSL in many asphalt produ ct s. Lower percentage s of most asphalt containing materials, when mixed with soil, tend ed to have lower PAH concentrations as well as lower bioaccessibility Bioaccessibility of the 11 asphalt pr oducts were all below 40%, with new asphalt shingles having a higher bioaccessibility than the other asphalt product s Diagnostic ratios indicate PAH of the asphalt products were from a combination of petrogenic and pyrogenic sources In most case s PAH c ontamination in CDD fines might not be elevated solely due to the presence of small pieces o f asphalt containing materials.

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61 4. 3 Future Implications Future research should focus on combining mec hanical shaking and fines washing process es to remove designate d size s of fines particles, which were conducted in this study to result in high chemical concentrations of concern. T he particle size boundary in this study was designated as 4.8 mm, but future research can focus on conducting more chemical analysi s on pa rticle sizes between 0.84 19 mm to provide a more specific size range for removal. For arsenic, the fines removal is not as efficient as the other chemicals since it distributes evenly in all size ranges However, since most arsenic concentrations detect ed in this research were below the commercial soil cleanup target level, arsenic may not be a major concern. In terms of PAH contamination in CDD fines, the presence of small pieces of asphalt product do es not apparently result in dramatically elevated concen tration s

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62 APPENDIX A FIGURES Figure A 1. Mixed CDD processing diagram Figure A 2. Comparison of Al concentration mass distribution as a function of particle size for 14 samples in triplicate 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of Al concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm

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63 Figure A 3. Comparison of Cd concentration mass distribut ion as a function of particle size for 14 samples in triplicate Figure A 4. Comparison of Cr concentration mass distribution as a function of particle size for 14 samples in triplicate 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of Cd concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of Cr concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm

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64 Figure A 5. Comparison of Cu concentration mass distribution as a function of particle size for 14 samples in triplicate Figure A 6. Comparison of Ni concentration mass distribution as a function of particle size for 14 samples in triplicate 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of Cu concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of Ni concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm

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65 Figure A 7. Comparison of Zn concentration mass distribution as a functio n of particle size for 14 samples in triplicat e Figure A 8. Compos ition study of 14 samples on different size f ractions 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% A B C D E F G H I J K L M N Cummulative Percentage of Zn concentrations Samples 4.8-19mm 0.84-4.8mm 0.30-0.84mm < 0.30mm

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66 APPENDIX B TABLE S Table B 1 Table of 16 EPA Priority PAHs. EPA 16 priority PAHs # of rings Naphthalene 2 Acenaphthene 3 Acenaph thylene 3 Anthracene 3 Phenanthrene 3 Fluorene 3 Fluoranthene 4 Benzo(a)anthracene 4 Chrysene 4 Pyrene 4 Benzo(a)pyrene 5 Benzo(b)fluoranthene 5 Benzo(k)fluoranthene 5 Dibenz(a,h)anthracene 6 Benzo(g,h,i)perylene 6 Indeno[1,2,3 cd]pyrene 6

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67 Table B 2 Mass distribution on different sieve sizes in duplicate (g). Sieve Size A B C D E F G H I J K L M N 4.8 19mm 163.3 136.3 150.7 139.3 11.5 215.8 451.0 442.9 124.9 332.1 114.4 112.7 258.3 295.6 0.84 4.8mm 168.9 470.9 132.5 286.0 391.0 180.1 614.8 558.4 237.7 162.2 173.7 286.1 297.2 132.9 0.30 0.84mm 59.5 60.0 64.3 100.1 147.4 206.8 298.9 201.2 229.1 96.4 118.2 233.8 184.3 62.4 <0.3mm 47.3 26.8 38.4 92.8 42.8 261.7 108.9 222.0 151.1 122.0 119.4 130.3 82.1 87.0 Table B 3. VS c ontent measure d on different sieve sizes in duplicate (g ) Samples 4.8 19 mm sieve 0.84 4.8 mm sieve 0.30 0.84 mm sieve < 0.30 mm sieve A 63.1 32.8 7.38 4.92 B 13.2 71.6 6.48 3.78 C 73.4 64.3 27.4 13.6 D 22.2 31.8 6.80 3.76 E 2.53 83.7 32.7 5.82 F 56.7 47.7 19.9 19.8 G 81.2 15 8.6 29.9 12.3 H 109.8 103.3 18.2 20.0 I 15.2 18.0 18.9 15.3 J 42.9 32.1 13.2 20.4 K 5.26 31.6 9.26 12.9 L 7.20 32.0 4.37 7.31 M 38.7 67.8 27.3 9.19 N 87.2 23.7 8.55 12.4 ave rage 44.2 57.1 16.5 11.5 Table B 4. As concentrations on d ifferent sieve sizes and the total weighted average As concentrations for all 14 samples in triplicate (mg/kg) *Average SD: 1.27 Sieve Size A B C D E F G H I J K L M N 4.8 19mm 5.9 2.27 14.2 1.57 6.35 0.85 14.3 5.45 6.23 2.19 2.74 2.93 5.54 1.85 0.84 4.8m m 9.07 4.21 10.6 1.78 9.41 3.07 9.69 7.43 3.2 2.45 4.08 6.04 5.56 2.09 0.30 0.84mm 7.16 3.59 9.32 2.18 10.4 5.35 8.19 7.95 3.39 2.52 3.78 4.28 6.98 2.46 < 0.30mm 7.85 3.72 7.93 3.26 3.93 4.29 8.67 12.1 5.23 2.93 3.96 3.67 6.75 2.37 weighted average sum 7.50 3.76 11.53 2.02 9.20 3.43 10.72 7.62 4.18 2.42 3.69 4.64 5.99 2.05

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68 Table B 5. Pb concentrations on different sieve sizes and the total weighted average Pb concentrations for all 14 samples in triplicate (mg/kg) *Average SD: 4.32 Table B 6. Gypsum content for 14 s ample s obtai ned on different size fractions in duplicate Samples 4.8 mm Sieve 0.84 mm Sieve 0.30 mm Sieve <0.30 mm Sieve % of Weighted average A 0.29% 7.08% 11.8% 19.5% 6.53% B 12.2% 16.2% 18.7% 19.5% 15.8% C 3.6% 12.4% 15.2% 15.3% 9.72% D 11.5% 11.8% 14.9% 19.3% 13.4% E 13.7% 13.0% 15.3% 16.4% 13.8% F 4.42% 5.32% 6.11% 5.36% 5.30% G 8.21% 10.9% 15.3% 12.6% 11.1% H 1.55% 4.29% 4.61% 7.54% 3.99% I 6.57% 13.7% 13.6% 18.2% 13.4% J 17.0% 18.4% 14.2% 29.6% 19.1% K 19.0% 15.0% 16.2% 22.7% 17.9% L 4.99% 9.90% 13. 2% 13.0% 10.7% M 5.46% 2.70% 2.47% 5.99% 3.84% N 6.40% 9.73% 13.2% 20.3% 10.0% Average 8.21% 10.74% 12.49% 16.09% 11.04% Sieve Size A B C D E F G H I J K L M N 4.8 19mm 8 .00 19.3 260.1 15.8 13.9 5245 163.5 502.2 16.5 6.76 3.72 4.08 46.9 24.8 0.84 4.8mm 69.9 18.6 510.5 79.5 15.4 1335 764.4 928.8 139.5 19.4 9.22 5.1 0 147.5 700.7 0.30 0.84mm 200.9 96 .0 1478 141.1 18.2 933 .0 1249 1250 323 .0 154 28.6 5.83 71.4 130.4 < 0.30mm 172.8 73.2 1608 191.2 31.5 312 .0 937.6 1898 267.6 51.9 27.4 7.4 0 53.1 193 .0 weighted average sum 75.7 27.5 683.3 91.9 17.2 1905 691.6 992.6 201.5 37.3 16.5 5.57 89.4 217.0

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69 Table B 7 Al concentrations on different sieve sizes and the total weighted average Al concentrations for all 14 samples in triplicate (mg/kg) *Average SD: 0.99 Table B 8 Cd concentrations on different sieve sizes and the total weighted average Cd concentrations for all 14 samples in triplicate (mg/kg) *Average SD: 1.29 Table B 9 Cr concentrations on different sieve sizes and the total weighted average Cr concentrations for all 14 samples in triplicate (mg/kg) *Average SD: 4.17 Sieve Size A B C D E F G H I J K L M N 4.8 19mm 4526 3662 2398 4718 5858 1 758 4218 5666 4435 4553 10940 5552 4571 1007 0.84 4.8mm 6266 7576 4895 5739 6201 4292 4906 5741 5214 4752 9 928 9085 8356 8375 0.30 0.84mm 6846 5828 3333 4713 5347 4 976 5093 5236 4931 4499 8557 6955 6013 5412 < 0.30mm 5888 7584 4437 6716 5298 5931 5438 6881 6676 4694 9656 6673 7556 7817 weighted average sum 5656 6656 3614 5489 5917 4319 4772 5824 5293 4615 9778 7498 6561 4203 Sieve Size A B C D E F G H I J K L M N 4.8 19mm 0.86 0.46 0.53 0.71 0.78 1.06 0.96 2.00 0.56 0.28 0.43 0.20 0.42 1.12 0.84 4.8mm 0.89 0.76 1.40 0.62 0.87 1.23 2.46 2.42 0.98 4.17 0.89 0.50 1.32 2.28 0.30 0.84mm 1.26 1.46 2.12 0.71 1.13 2.06 2.00 1.92 1.00 0.85 0.58 0.39 1.12 0.87 < 0.30mm 13.7 26.2 3.38 2.56 2.22 1.81 2.37 2.92 1.39 0.81 0.77 0.47 0.75 1.04 weighted average sum 2.31 1.74 1.38 0.95 1.03 1.56 1.90 2.30 1.00 1.33 0.69 0.42 0.94 1.35 Sieve Size A B C D E F G H I J K L M N 4.8 19mm 17.3 12.6 8.3 12.4 13.9 4.9 25.0 11.2 27.1 9.5 38.4 12.8 11.7 4.7 0.84 4.8mm 24.9 18.1 16.1 12.3 19.2 17.6 20.7 19.5 22.9 29.2 23.4 22.3 22.4 16.4 0.30 0.84mm 29.3 26.1 12.1 13.0 17.8 20.7 18.3 20.7 25.3 17.6 22.7 20.1 18. 1 16.6 < 0.30mm 23.0 27.3 21.5 20.6 18.5 15.3 20.4 25.6 30.8 15.9 28.5 20.5 21.2 21.0 weighted average sum 22.5 18.1 12.9 13.7 18.7 14.5 21.5 18.0 26.0 16.2 27.7 19.9 18.0 11.1

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70 Table B 10 Cu concentrations on different sieve sizes and the total weighted average Cu concentrations for all 14 samples in triplicate (mg/kg) *Average SD: 2.29 Table B 11 Ni concentrations on different sieve sizes and the total weighted average Ni concentrations for all 14 samples in triplicate (mg/kg) *Average SD: 2.00 Table B 12 Zn concentrations on different sieve sizes and the total weighted average Zn concentrations for all 14 samples in triplicate (mg/kg) *Average SD: 5.91 Sieve Size A B C D E F G H I J K L M N 4.8 19mm 12.8 16.8 22.0 5.6 30.8 2.7 16.4 22.3 7.5 12.1 22.7 10.1 45.3 9.9 0.84 4.8mm 22.3 66.9 47.9 11.6 52.0 21.5 37.6 38. 6 35.2 18.9 29.8 51.9 175.2 21.5 0.30 0.84mm 30.6 30.9 44.1 15.8 48.0 112.4 32.0 51.7 50.5 53.7 29.7 30.2 105.9 104.5 < 0.30mm 66.4 67.9 170.9 65.4 82.9 53.0 107.6 97.3 140.4 46.3 79.5 103.0 177.0 233.7 weighted average sum 24.6 54.0 49.4 19.0 52.8 48.1 35.1 44.5 56.7 25.1 39.5 47.8 119.0 56.5 Sieve Size A B C D E F G H I J K L M N 4.8 19mm 9.66 10.1 38.7 4.23 12.0 4.25 11.4 10.2 9.06 5.09 12.3 6.67 11.2 2.27 0.84 4.8mm 19.2 13.6 14.2 5.44 15.4 11.5 12.4 16.5 18.0 15.9 11.6 13.2 19.5 10.3 0.30 0.84mm 25.6 19.6 11.5 5.31 15.2 16.1 21.0 15.2 20.2 12.0 11.1 11.6 9.60 7.77 < 0.30mm 30.3 48.7 2 2.5 12.3 17.2 12.3 18.1 18.5 27.2 8.72 13.2 13.6 12.1 13.6 weighted average sum 17.7 14.8 24.1 6.2 15.4 11.0 14.3 14.7 19.0 9.11 12.0 11.8 13.9 6.42 Sieve Size A B C D E F G H I J K L M N 4.8 19mm 63.1 85.6 197.5 306.9 142.4 478.1 160.7 515.3 43.4 22.1 33.3 28.4 286.1 35.0 0.84 4.8mm 167.7 94.4 492.1 272.0 177.8 700.3 354.6 456.9 244.9 346.8 83.1 69.5 563.6 125.1 0.30 0.84mm 552.7 210.8 844.6 197.0 251.2 411.4 456.1 507.3 404.9 237.0 84.0 95.1 309.9 285.1 < 0.30mm 468.6 293.4 830.6 267.7 234.1 278.3 479.2 688.5 495.7 143.9 121.3 114.5 198.4 394.3 weighted average sum 213.3 110.4 469.6 267. 1 199.4 448.0 325.1 518.3 311.4 145.9 81.1 79.0 383.0 136.8

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71 Table B 13 Florida SCTL and National RSL for detected chemicals (mg/kg) Parameters RSL (Residential) RSL (Industrial) FSCTL (Residential) FSCTL (Industrial) Arsenic (As) 0. 68 3.0 2.1 12 Lead (Pb) 400 800 400 1400 Benzo[a]pyrene (BaP) 0.016 0.29 0.1 0.7 Naphthalene (NA) 38 170 55 300 Acenaphthene (ACE) 3600 45000 2400 20000 Phenanthrene (PH) 2200 36000 Fluorene (FL) 2400 30000 2600 33000 Anthracene (ANC) 18000 2300 00 21000 300000 Fluoranthene (FLU) 2400 30000 3200 59000 Pyrene (PY) 1800 23000 2400 45000 Benzo[a]anthracene (BaA) 0.16 2.9 Benzo[b]fluoranthene (BbF) 0.16 2.9 Chrysene (CH) 16 290 Benzo[g,h,i]perylene (BP) 2500 52000 Anthanthrene ( AN) 18000 230000 21000 300000 Dibenz[a,h]anthracene (DhA) 0.016 0.29 Dibenzo[a,l]pyrene (DlP)

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72 LIST OF REFERENCE S Abdel Shafy, H. I., Mansour, M. S.M. 2016 A Review on Polycyclic Aromatic Hydrocarbons: Source, Environmental Impact, Ef fect on Human Health and Remediation. Egyptian Journal of Petroleum 25, 107 123. A ichner, B., Bussian, M.B., Lehnik Habrink, P., Hein, S. 2015 Regionalized Concentration and Fingerprints of Polycyclic Aromatic Hydrocarbons (PAHs) in German Forest Soils. Environmental Pollution 203, 31 39. Azah, E., 2011 The Impact of Polycyclic Aromatic Hydrocarbons (PAHs) on Beneficial Use of Waste Materials. ProQuest LLC. Azah, E., Kim, H., Townsend, T. 2015 Source of Polycyclic Aromatic Hydrocarbon in Roadway and St ormwater System Maintenance Residues. Environmental Earth Science 74, 3029 3039. Grung, M., Anderson, K. A., Ranneklev, S. B. 2016 PAH Accessibility in Particulate Matter from Road Impacted Environment s. Environmental Science & Technology 50, 7964 7972. Banger, K., Toor, G.S., Chirenje, T., Ma, L. 2010 Polycyclic Aromatic Hydrocarbons in Urban Soils of Different Land Uses in Miami, Florida. Soil and Sediment Contamination 19, 231 243. B iache, C., Mans uy Huault, L., Faure, P. 2014 Impact of Oxidation and Biodegradation on the Most Commonly Used Polycyclic Aromatic Hydrocarbon (PAH) Diagnostic Ratios: Implications for the Source Identifications. Journal of Hazardous Materials 267, 31 39. Brantley, A. S ., Townsend, T. 1999 Leaching of Pollution from Reclaimed Asphalt Pavement. Environmental Engineering Science 16, 105 116. Brandt, H. C. A., Groot, P. C. D. 2001 Aqueous Leaching of Polycyclic Aromatic Hydrocarbons from Bitumen and Asphalt. Water Resea rch 35, 4200 4207. Brandli, R. C., Bucheli, T. D., Kupper, T., Mayer, J., Stadelmann, F. X., Tarradellas, J. 2007 Fate of PCBs, PAHs and Their Source Characterostic Ratios During Composting and Digestion of Source Separated Organic Waste in Full Scale Pl ants. Environmental Pollution 148, 520 528. Colombo, J. C., Pell etler, E., Brochu, C., Kjalll, M., 1999 Dertermination of Hydrocarbon Sources Using n Alkane and Polyaromatic Hydrocarbon Distribution Indexes. Case Study: Rio de La Plata Estuary, Argentina Environmental Science and Technology 23, 888 894.

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73 Cui, X., X iang, P., He, R., Juhasz, A., Ma, L. Q. 2016 Advances in in vitro methods to evaluate oral bioaccessibility of PAHs and PBDEs in Environmental Matrices. Chemosphere 150, 378 389. Daniela M. P ., Magne O. S., 2013 Polycyclic Aromatic Hydrocarbons a Constituent of Petroleum: Presence and Influence in the Aquatic Environment, Hydrocarbon, Dr. Vladimir Kutcherov (Ed.), InTech, Chapter 5. (Available from: http://www.intechopen.com/books/hydrocarbon /polycyclic aromatic hydrocarbons a constituent of petroleum presence and influence in the aquatic en) DS M Environmental Services, Inc, 2008 2007 Massachusetts construction and demolition debris industry study. Massachusetts Department of Environmental Pr otection. Dobbins, R. A., Fletcher, R. A., Benner Jr, B. A., Hoeft, S., 2006. Polycyclic Aromatic Hydrocarbons in Flames, in Diesel Fuels, and in Diesel Emissions. Combustion and Flame 144, 773 781. Federal Register 1996 Lead; Requirements for Lead Based Paint Activities in Target Housing and Child Occupied Facilities. Environmental Protection Agency. 61:169. Fernandes, P. R. N., Soares, S. A., Nasc imento, R. F., Soares, J. B., Cavalcante, R. M., 2009. Evaluation of Polycyclic Aromatic Hydrocarbons in Asp halt Binder Using Matrix Solid Phase Dispersion and Gas Chromatography. Journal of Chromatographic Science 47, 789 793. FDEP, 2005 Soil Cleanup Target Levels. Contaminant Cleanup Target Levels Table II Chapter 62 777. FDEP, 2011. Guideli nes for The Management of Recovered Screen Material from C&D Debris Recycling Facilities in Florida. Gomez Eyles, J .L., Jon ker, M. T. O., Hodson, M. E., Collins, C. D., 2012. Passive Samplers Provide a Better Prediction of PAH Bioaccumulation in Earthworm s and Plant Roots than Exhaustive, Mild Solvent, and Cyclodextrin Extractions. Environmental Science & Technology 46, 962 969. Hussar, E., Richards, S., Lin, Z. Q., Dixon, R. P., Johnson, K. A. 2012. Human Health Risk Assessment of 16 Priority Polycyclic Aromatic Hydrocarbons in Soils of Chattanooga, Tennessee, USA. Water Air Soil Pollution 22 3, 5535 5548. Jang, Y., Townsend, T., 2001 Sulfate Leaching from Recovered Construction and Demolition Debris Fines. Advances in Environmental Research 5, 203 217. J ang, Y., Townsend, T. 2001. Occurrence of Organic Pollutants in Recovered Soil Fines from Construction and Demolition Waste. Waste Management 21, 703 715.

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74 Johnsen, A. R., Lipthay, J. R., Reichenberg, F., Srensen, S. J., Andersen, O., C hristensen, P., Bin derup, M., Jacobsen, C. S. 2006 Biodegradation, Bioaccessibility, and Genotoxicity of Diffuse Polycyclic Aromatic Hydrocarbon (PAH) Pollution at a Motorway Site. Environmental Science and Technoloty 40, 3293 3298. Katsoyiannis, A., Terzi, E., Cai, Q. Y. 2007 On the Use of PAH Molecular Diagnostic Ratios in Sewage Sludge for the Understanding of the PAH Sources. Is this use appropriate? Chemosphere 69, 1337 1339. Lee, B. K., Vu, V. T. 2010 Sources, Distribution and Toxicity of Polycyclic Aromatic Hydro carbons (PAHs) in Particulate Matter. Chapter 5, Air Pollution. Liste, H. H., Alexander, M. 2002. Butanol Extraction to Predict Bioavailability of PAHs in Soil. Chemosphere 46, 1011 1017. Li, C., Sun H., Juhasz, A. L., Cui, X., Ma, L. Q. 2015 Predicting the Relative Bioavailability of DDT and Its Metabolites in Historically Contaminated Soils Using a Tenax Improved Physiologically Based Extraction Test (TI PBET). Environmental Science and Technology 50, 1118 1125. Ma, L. Q., Tan, F., Harris, W. G. 1997 Concentrations and Distributions of Eleven Metals in Florida Soils. Journal of Environmental Quality 26, 769 775. Man, Y. B., Kang, Y., Wang, H. S., Lau, W., Li, H., Sun, X. L., Gi esy, J. P., Chow, K. L., Wong, M. H. 2013. Cancer Risk Assessments of Hong Kong Soils Contaminated by Polycyclic Aromatic Hydrocarbons. Journal of Hazardous Materials 261, 770 776. Montero, A., Tojo, Y., Matsuo, T., Yamada, M., Asakura, H., Ono, Y., 2010. Gypsum and Organic Matter Distribution in a Mixed Construction and Demolit ion Waste Sorting Process and Their Possible Removal from Outputs. Journal of Hazardous Materials 175, 747 753. Musson, S., Xu, Q., Townsend, T. 2008 Measuring gypsum content of C&D debris fine. Waste Management 28, 2091 2096. Review P aper. Khan, Z., Tr oquet, J., Vachelard, C. 2005 Sample Preparation and Analytical Techniques for Determination of Polyaromatic Hydrocarbons in Soils. Inernational Journal of Environmental Science and Technology 2, 275 286. Ruby, M. V., Lowney, Y. W., Bunge, A. L., Roberts S. M., Gomez Eyles, J. L., Ghosh, U., Kissel, J. C., Tomlinson, P., Menzie, C. 2016 Oral Bioavailability, Bioaccessibility, and Dermal Absorption of PAHs from Soil --State of the Science. Environmental Science & Technology 50, 2151 2164. Schauer, J. J ., Kleeman, M. J., Cass, G. R., Simoneit, B. R. T., 1999. Measurement of Emissions from Air Pollution Sources. 2. C 1 through C 30 Organic Compounds from Medium Duty Diesel Trucks. Environmental Science and Technology 33, 1578 1587.

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75 Solo Gabriele, H., Townse nd, T., Messick, B., Calitu, V., 2002 Characteristics of Chromated Copper Arsenate Treated Wood Ash. Journal of Hazardous Materials B89, 213 232. Swindell, A. L., Reid, B. J. 2006. Comparison of Selected Non Exhaustive Extraction Techniques to Assess PAH Bioavailability in Dissimilar Soils. Chemosphere 62, 1126 1134. Sun, W., Barlaz, M.A. 2015 Measurement of Chemical Leaching Potential of Sulfate from Landfill Disposed Sulfate Containing Wastes. Waste Management 36, 191 196. Tang, B., Isacsson, U. 2006 Chemical Characterization of Oil based Asphalt Release Agents and Their Emissions. Fuel 85, 1232 1241. Townsend, T., Tolaymat, T. Leo, K., Jambeck, J. 2004 Heavy Metals in Recovered Fines from Construction and Demolition Debris Recycling Facilities in Florida. Science of the Total Environment 332, 1 1 1 US EPA, 1996 SW 846 Test Method 3050B : Acid Digestion of Sediments, Sludges, and Soils. USEPA. US EPA, 2000. Hot Mix Asphalt Plants Emission Assessment Report. The Office of Air Quality Planning and St andards, Research Triangle Park, N.C. US EPA, 2001 Total, fixed, and volatile solids in water, solids, and biosolids. (Report No. 821 R 01 015) Washington DC. US EPA, 2007. SW 846 Test Method 3550C: Ultrasonic Extraction. The Office of Resource Conservati on and Recovery, Washington D.C. US EPA, 2014. EPA Positive Matrix Factorization (PMF) 5.0 Fundamentals and User Guide. Research Triangle Park. US EPA, 2016 Construction and demolition debris generation in the United States, 2014. Office of Resource Cons ervation and Recovery. USEPA, 2016. Regional Screening Level (RSL) Summary Table (TR=1E 06, HQ=1). Regional Screening Levels (RSLs) Generic Tables. Washington State Department of Ecology, 2014 Table 740 1 Method A soil cleanup levels for unrestricted l and uses. (WAC 173 340 900). Williams, P. T., Bartle, K. D., Andrews, G. E ., 1986. The Relation Between Polycyclic Aromatic Compounds in Diesel Fuels and Exhaust Particulates. Fuel 65, 1150 11158.

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76 Yunker, M. B., Macdonald, R. W., Vingarzan, R., Mitchell, R H., Goyette, D., Sylvestre, S. 2002 PAHs in the Fraser Ricer Basin: a Critical Appraisal of PAH Ratios as Indicators of PAH Source and Composition. Organic Geochemistry 33, 489 515.

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77 BIOGRAPHICAL SKETCH Jing Su was born in 1992 The place of birth wa s in Suzhou, China. She went to schoo l in Suzhou and opted to study C hinese mathematics, E nglish, physics and chemistry as her major subjects in Suzhou High School since 2008. Then she enrolled in a joint degree program between Nanjing Xiaozhuang Universi ty (China) and Keele University (UK) in 2011, and graduated with a Bachelor of Science degree in environmental science from both universities. In August 2015, she enrolled in the Environmental Engineering Sciences Department at the University of Florida an d started to concentrate in the field of solid and hazardous waste.