Results of Soil Sampling Investigation and Health Risk...

Results of Soil Sampling Investigation and Health Risk Assessment Heron’s Head Park – Pier 98 San Francisco, California

Prepared for:

Port of San Francisco Pier 1 San Francisco, California 94111

February 2004

Project No. 8621.003

Results of Soil Sampling Investigation and Health Risk Assessment Heron’s Head Park – Pier 98 San Francisco, California

Prepared for:

Port of San Francisco Pier 1 San Francisco, California 94111

Prepared by:

Geomatrix Consultants, Inc. 2101 Webster Street, 12th Floor Oakland, California 94612

February 2004

Project No. 8621.003

I:\Doc_Safe\8000s\8621.003\Report\Report dftfnl.doc i

TABLE OF CONTENTS

Page

1.0 INTRODUCTION.............................................................................................................1 1.1 BACKGROUND ........................................................................................................1 1.2 OBJECTIVE..............................................................................................................1

2.0 SUMMARY OF PREVIOUS ENVIRONMENTAL INVESTIGATIONS ......................2

3.0 SOIL SAMPLING PROGRAM ........................................................................................3 3.1 FIELD METHODS.....................................................................................................4 3.2 FINDINGS................................................................................................................5

4.0 HEALTH RISK ASSESSMENT.......................................................................................6 4.1 DATA EVALUATION................................................................................................7 4.2 EXPOSURE ASSESSMENT.........................................................................................8 4.3 TOXICITY ASSESSMENT ........................................................................................10 4.4 RISK CHARACTERIZATION ....................................................................................10 4.5 UNCERTAINTIES....................................................................................................11

5.0 CONCLUSIONS .............................................................................................................12

6.0 LIMITATIONS ...............................................................................................................12

7.0 REFERENCES ................................................................................................................13

TABLES

Table 1 Soil Sample Analytical Results - Metals Table 2 Soil Sample Analytical Results - Polynuclear Aromatic Hydrocarbons Table 3 Exposure Parameters for Adolescent Student Table 4 Exposure Parameters for Recreational User (Child/Adult) Table 5 Summary of Noncarcinogenic Hazard Indices- Adolescent Student Table 6 Summary of Excess Lifetime Cancer Risks- Adolescent Student Table 7 Summary of Noncarcinogenic Hazard Indices- Recreational User (Child/Adult) Table 8 Summary of Excess Lifetime Cancer Risks- Recreational User (Child/Adult)

FIGURES

Figure 1 Site Location Map Figure 2 Site Layout and Soil Boring Locations

APPENDIXES

Appendix A Boring and Right-of-Entry Permits Appendix B Boring Logs Appendix C Laboratory Analytical Reports and Chain-of-Custody Records Appendix D Supporting Risk Calculations

I:\Doc_Safe\8000s\8621.003\Report\Report dftfnl.doc 1

RESULTS OF SOIL SAMPLING PROGRAM AND HEALTH RISK ASSESSMENT

Heron’s Head Park – Pier 98 San Francisco, California

1.0 INTRODUCTION

Geomatrix Consultants, Inc. (Geomatrix) has prepared this report to present the results of a soil sampling program and a health risk evaluation performed at Heron’s Head Park, also known as Pier 98, in southeast San Francisco, California (the Site; Figure 1). The work described herein was performed in accordance with Geomatrix’s March 26, 2003 scope of services (Geomatrix, 2003).

1.1 BACKGROUND The Site is approximately 27-acres located on the north side of India Basin (Figure 2). The Site is owned by the Port of San Francisco (the Port) and was created through the construction of a debris dike and the placement of fill material potentially consisting of dredge spoils, miscellaneous debris, and decomposable waste (non-inert fill) in the early 1970s for the construction of a marine shipping terminal (Tetra Tech, 1998). In 1977, the placement of fill was stopped. Subsequently, three acres at the southeastern portion of the Site was naturally transformed into a salt marsh. In 1998, the Port covered the western portion of the Site with a geosynthetic clay liner and approximately 1.5 to 3 feet of soil to minimize infiltration of rain water through the underlying fill. In addition, the Port, with assistance from Literacy for Environmental Justice (LEJ) and other local community groups and organizations, i) enhanced and increased the total acreage of the tidal salt marsh by another 5 acres; ii) cleared, graded, and revegetated the northwestern and upland portion of the Site; and iii) improved public access by constructing trails, viewing, and resting areas. The Site was renamed Heron’s Head Park and is now home to acres of tidal salt marsh housing shorebirds and other wildlife. The Site is used year-round for open space and educational and summer programs in cooperation with local schools and community organizations.

1.2 OBJECTIVE LEJ is sponsoring the construction of the Living Classroom, an environmental education center for youth-based programs and a meeting space for community groups, on the upland portion of the Site (Figure 2). The objective of the recent soil sampling program was to characterize


shallow soil conditions at the Site and evaluate whether potential exposures to soil would pose an unacceptable health risk to future users of the property, based on the planned use of the Site as an educational center and recreational park, and if so, recommend mitigation activities.

2.0 SUMMARY OF PREVIOUS ENVIRONMENTAL INVESTIGATIONS

Several investigations have been conducted by others to characterize the nature of the fill, soil, and groundwater at the Site. Information from these studies is summarized below.

Fill is present to approximate depths of 15 feet below ground surface (bgs) and consists of varying mixtures of gravel, sand, silt, clay, and debris material, such as wood, plastic, concrete, and brick. The fill is underlain by Bay Mud which consists of clay and sandy clay between approximately 15 and 44 feet bgs. Bedrock is present at depths between 50 to 200 feet bgs near the west and east ends of the site, respectively. Local groundwater occurs within fill at depths ranging from 2 to 14 bgs (Geo/Resource, 1989).

Data collected at the Site in October 1988 and January 1989 indicate the presence of volatile organic compounds (VOCs), metals, and polynuclear aromatic hydrocarbons (PAHs) in subsurface soil (Geo/Resource, 1989 and the Mark Group, 1989). Soil gas samples were collected by the Mark Group at five locations within the Site. Soil gas samples were collected by sampling the air three inches immediately above the surface of the Site. Low concentrations (less than 5 parts per billion per volume [ppbv]) of VOCs, specifically benzene, tetrachloroethene (PCE), and trichloroethene (TCE) were detected in at least one soil gas sample. Methane was not detected above the laboratory reporting limit. The report concluded that the Site did not appear to be a potential source of VOCs affecting ambient air quality (the Mark Group, 1989).

Nine soil borings were advanced by Geo/Resource, Inc. to collect soil samples in January 1989. Except for three (3) soil samples from three (3) locations (GW-1, GW-5, and B-4), available data were from soil samples collected at depths greater than 5 feet bgs (Geo/Resource, 1989). Analytical results of soil samples indicate that some metals and select PAHs were present at concentrations that exceed designated levels to protect groundwater, surface water, and marine water. VOCs were not detected above the laboratory sample quantitation limits (SQLs) from soil samples collected within the top 5 feet of soil. However, ethylbenzene and xylenes were detected at 16 feet bgs. No other VOCs were detected at depths greater than 5 feet bgs. Pesticides and polychlorinated biphenyls (PCBs) were not detected above the SQLs.


In 1998, 15 near surface soil samples were collected by Tetra Tech, Inc. (Tetra Tech), from 12 locations, and analyzed for pH, cyanides, sulfides, ignitability, and arsenic to comply with the City of San Francisco’s Maher Ordinance (Article 22A). Total arsenic concentrations in soil were detected up to 3.6 milligrams per kilogram (mg/kg) and are well below the concentration considered as regional background (LBNL, 1995). Results of the other analyses indicate that soil at the Site would not be classified as a hazardous waste (Tetra Tech, 1998). Since 1998, some of the soil was moved around the Site as part of wetland restoration activities.

3.0 SOIL SAMPLING PROGRAM

Information from the above-mentioned field investigations was reviewed to evaluate the adequacy of data to support a site-specific risk assessment for future users of the Living Classroom at the Site. As discussed below, the historical data were assessed to be incomplete to support a complete identification of potential chemicals of concern that may be present at the Site and additional data collection was deemed necessary to characterize current conditions. The findings from previous environmental investigations indicate that metals, PAHs, and VOC are likely present in soil. However, the majority of the samples were collected at depths to which future exposures from direct contact (i.e., incidental soil ingestion, dermal contact, and inhalation of dust) are unlikely. In addition, the historical data were collected prior to Site restoration activities and potentially do not represent current site conditions. Thus, a focused sampling program targeting chemicals previously detected at the Site was proposed and conducted.

The field sampling program consisted of the collection and analysis of surface soil samples from 13 shallow soil borings (B-2 through B-14). Surface soil represents the soil to which future receptors are likely exposed from direct contact and is generally defined as soil collected within the top 5 feet, typically at depths between 0 and 2 feet bgs. Because VOCs are not likely to be present at or near the surface, soil samples for VOCs were collected at 3 feet bgs. The Site layout and boring locations are shown on Figure 2. The borings were located spatially to allow the broadest coverage over the portion of the property that was publicly accessible. Access to the wetland inter-tidal area is restricted and protected by a perimeter rope, and therefore, no samples were collected in this area.

Prior to conducting field activities, Geomatrix marked boring locations, contacted Underground Service Alert, and contracted with Subsurface Locating Services, of Petaluma, California, a private utility locator, to perform an underground utility clearance at each boring location. In


addition, Geomatrix prepared a site-specific health and safety plan. Boring permits and a right-of-entry permit were obtained from the City and County of San Francisco Department of Public Health and the San Francisco Port Commission, respectively (Appendix A).

3.1 FIELD METHODS

The borings were advanced by Precision Sampling, Inc. (Precision), of Richmond, California, a state-licensed drilling contractor, using a hydraulically driven, direct-push drilling rig with a 2-inch (inner diameter) macro-core sampler with butyrate sampling sleeves for soil sample collection and logging. Drilling and sampling equipment were steam cleaned prior to use at each location.

Nine of 13 borings were advanced to a depth of approximately 1 feet bgs. Four of the 13 borings (B-2, B-3, B-4, and B-6) were advanced to a depth of approximately 3 feet bgs for the collection of deeper soil samples. A nearly continuous soil core was generated from each of the deeper soil borings and logged by Geomatrix personnel according to the Unified Soil Classification System (USCS) as presented in the American Society of Testing Materials (ASTM) Standard D2488-90. Soil characteristics including visual grain size, Munsell color, moisture content, plasticity of fine-grained soils, and other pertinent features were recorded on the boring logs. Copies of the soil boring logs are provided in Appendix B. Recovered soil was screened with an organic vapor meter (OVM) equipped with a photoionization detector (PID). Soil samples were collected for chemical analysis from all borings at depths between 0.5 and 1 feet bgs. One additional soil sample was collected from the four deeper borings at 3 feet bgs. Each soil boring was backfilled to the ground surface with granular bentonite and hydrated with potable water.

Soil samples for chemical analysis were collected in clean, butyrate liners, sealed with Teflon sheets, plastic end caps, and silicon tape. Samples were labeled and stored in an ice-cooled chest for delivery to STL San Francisco (STL), of Pleasanton, California, a state-certified analytical laboratory, under Geomatrix chain-of-custody procedures. A copy of the chain-of-custody record is included in Appendix C.

A total of 13 near surface soil samples and four (4) deeper soil samples were collected for chemical analysis. Near surface soil samples (1 feet bgs) were analyzed for California Assessment Manual (CAM) 17 metals using U.S. Environmental Protection Agency (EPA)


Method 6000/7000 series and PAHs using EPA Method 8270C selective ion monitoring (SIM). Soil samples collected at 3 feet bgs were analyzed for VOCs using EPA Method 8260B.

3.2 FINDINGS

Based on the soil cores observed during drilling, shallow soil beneath the site is primarily silty sand with some clayey gravel and sand to 3 feet bgs, the maximum depth drilled to during this field program. Groundwater was not encountered in any of the borings. PID measurements were taken of the soil core during drilling of all borings; PID readings were 0 parts per million.

Analytical results for the soil samples are summarized in Tables 1 and 2. Copies of the analytical laboratory reports are included in Appendix C.

To place the results in context and to preliminarily assess whether any of the chemicals detected in soil are present at concentrations of potential concern, concentrations of chemicals in soil were compared to the San Francisco Bay Area Regional Water Quality Control Board (RWQCB) Environmental Screening Levels (ESLs; RWQCB, 2003) and naturally-occurring background concentrations of metals in colluvium fill from the Lawrence Berkeley National Laboratory (LBNL, 1995). The ESLs are conservative screening levels that correspond to an acceptable risk level and reflect varying combinations of site characteristics including both residential and industrial land uses. Concentrations of compounds detected below corre-sponding ESLs can be assumed to not pose a significant threat to human health and the en-vironment. Conversely, exceedance of the corresponding ESL does not necessarily indicate that adverse environmental effects will occur but suggests that additional evaluation of the potential risks may be warranted. For this evaluation, residential ESLs developed for surface soil where groundwater is a current or potential source of drinking water were used (RWQCB, 2003).

Antimony, beryllium, selenium, silver, and thallium were not detected in any of the soil samples. All detected metals, other than arsenic and nickel, were detected at concentrations below background and their respective ESLs. Arsenic was detected in all soil samples below regional background but above the residential ESL at concentrations between 2.4 and 8.4 mg/kg (Table 1). Cobalt, lead, and nickel were detected above regional background but were not detected above the ESLs. Nickel was detected above regional background and the residential ESL of 150 mg/kg at concentrations between 47 and 1,600 mg/kg.


As presented in Table 2, certain PAHs were detected above their respective residential ESLs, including benzo(a)anthracene, benzo(b)fluoranthene, benzo(k)flouranthene, benzo(a)pyrene, indeno(1,2,3-cd)pyrene, and dibenz(a,h)anthracene. Benzo(a)pyrene was detected in more than half of the soil samples at concentrations ranging from 7.8 to 1,500 micrograms per kilogram (µg/kg). The other PAHs were generally present in the same samples where benzo(a)pyrene was detected.

No VOCs were detected above the laboratory SQLs in any of the soil samples submitted for analysis.

4.0 HEALTH RISK ASSESSMENT

Based on the initial screening comparison of soil analytical results to ESLs, select PAHs and metals were detected in surface soil at concentrations exceeding screening criteria and regional background for metals. As indicated above, exceedance of screening criteria does not necessarily indicate that adverse environmental effects will occur, but suggests that additional evaluation of the potential risks is warranted. To account for the potential for adverse health effects associated with cumulative exposure to multiple chemicals, a health risk assessment was conducted to evaluate the potential health risks associated with site-specific exposure to chemicals detected at the Site.

The technical methods applied in this health risk assessment are based on regulatory guidelines recommended by the U.S. EPA (U.S. EPA, 1989, et seq.), the California EPA (Cal-EPA) Department of Toxic Substances Control (DTSC) standard risk assessment guidance (Preliminary Endangerment Assessment [PEA] Guidance Manual, 1994 [reprinted in 1999]), and consideration of site-specific conditions. Several supplemental guidance documents that reflect current Cal-EPA and U.S. EPA standards of practice also are referenced. The assumptions and approaches used in this evaluation are consistent with a Reasonable Maximum Exposure (RME) approach as defined by U.S. EPA (1989). The RME scenario is defined by U.S. EPA as the "highest exposure that is reasonably expected to occur at the site."

This health risk assessment is organized into sections that are consistent with the risk assessment steps outlined by U.S. EPA (1989): data evaluation, exposure assessment, toxicity assessment, risk characterization, and a qualitative discussion of the uncertainties associated with the risk assessment. Each of the steps is described below.


4.1 DATA EVALUATION Data evaluation is the process of analyzing site characteristics and analytical data to identify data of sufficient quality for inclusion in the risk assessment and, based on these data, identify chemicals of potential concern (COPCs). For this evaluation, the recent data collected by Geomatrix are judged to best represent the Site as it currently exists (Tables 1 and 2). These data were considered representative of Site conditions and served as the basis for the health risk evaluation.

Data collected in 1989 were not utilized because the data potentially represent pre-existing conditions as some of the soil has been moved around during Site restoration activities in 1998. Data collected in 1998 also were not utilized because arsenic was the only chemical analyzed and the concentrations were below the regional background for colluvium fill (LBNL, 1995).

Based on the information provided above, a statistical summary of the analytical data for the chemicals detected in soil are presented in Tables 3 and 4. These tables present the total number of samples analyzed, total number of detections, frequency of detection, range of detected concentrations, and range of quantitation limits. COPCs for the risk evaluation were identified using the following procedure:

1. For naturally occurring chemicals detected in soil, the data were first evaluated by comparing the concentrations detected at the site to concentrations considered in-dicative of regional background. The representative background data used in this comparison were collected by the Lawrence Berkeley National Laboratory (LBNL) for the purposes of establishing background concentrations of selected metals in the vicinity of the laboratory (LBNL, 1995). A chemical was considered to be present at the site at concentrations within representative background concentrations if the maximum concentration was below the 95% upper tolerance limit (UTL) of the LBNL data. If the concentration of the chemical at the site is greater than the representative background data, then that chemical was evaluated further as described below. If the concentration of the chemical is within the representative background data, then that chemical was not considered further.

2. For naturally occurring chemicals detected at concentrations greater than the repre-sentative background data and the remaining chemicals detected in soil, the data were evaluated by comparing the maximum concentration to ESLs for residential land use where groundwater is considered a current or potential source of drinking water (RWQCB, 2003). Use of the ESLs for residential land use is considered health protective because the future use of the Site is an educational center situated on a neighborhood park. A chemical was identified as a COPC if the maximum


detected concentration is greater than the appropriate ESL. If the chemical was not detected above the appropriate ESL, then that chemical was not considered further.

As shown in Tables 1 and 2 and based on this comparison, COPCs identified and quantitatively evaluated include: cobalt, nickel, benzo(a)anthracene, benzo(b)fluoranthene, benzo(k)flouranthene, benzo(a)pyrene, dibenz(a,h)anthracene, and indeno(1,2,3-cd)pyrene.

4.2 EXPOSURE ASSESSMENT Heron’s Head Park, as it exists today, is primarily open public space consisting of four different habitats: mudflats located along the southern and eastern perimeters; an inter-tidal salt marsh near the center of the site; a rocky shoreline along the northern perimeter; and an upland recreational area at the northwestern portion of the site with picnic tables and a barbeque pit. Access to the park is through an east-west trail. Native plants and grasslands are present on both sides of the trail. The Site is used by the public for educational programs, fishing, walking, and wildlife viewing.

The educational center will be constructed on the upland portion of the Site (Figure 2). The building footprint and the exterior area will cover approximately 2,850 square feet. Based on the intended use of the upland portion of the Site as an educational center, individuals potentially exposed to soil below native plants and grasslands at the Site include future students, school teachers, Living Classroom instructors (i.e., LEJ naturalist), and occasional recreational users (e.g., recreational adults walking or jogging on trail). Adolescents, ages 7 through 17, were selected as the primary age group for students because this is the age that would most likely access the park as part of educational field trips. As will be discussed below, the exposure frequency, which is the approximate total days exposed (i.e., the number of hours per day and the number of days at the site) for school teachers, Living Classroom instructors, and recreational users, is expected to be similar for all three receptors. Therefore, for the purpose of this evaluation, these three receptors were evaluated as a recreational user and conservatively as a combined child/adult (child age 0 to 6 years, and adult age 7 to 30 years).

Given the source (i.e., historical placement of fill), the chemical nature of the COPCs (i.e., non-volatile), and transport mechanisms, potential exposure routes associated with chemicals in surface soil are incidental ingestion, dermal contact, and inhalation of re-suspended particulates in air. These exposure routes are applicable to all receptors.


Exposure point concentrations are chemical concentrations that are considered representative of the average to which an individual might be exposed over an extended period of time. Representative concentrations in soil for each COPC were calculated as the 95% upper confidence limit (95% UCL) of the arithmetic mean based on a normal distribution. The 95% UCLs are considered by U.S. EPA as providing reasonable confidence that exposure point concentrations will not be underestimated under the RME scenario. At the 95% UCL, the probability of underestimating the true mean is less than 5 percent (U.S. EPA, 1992). One-half of the sample quantitation limit (SQL) was used as a proxy concentration for samples reported as non-detect (U.S. EPA, 1989). This approach assumes that, on average, all values between zero and the SQL could be present. In the event that the calculated 95% UCLs exceeded the maximum detected value, the maximum value was used as the exposure point concentration (Tables 3 and 4).

As part of the exposure assessment, chemical intakes are assessed for each pathway and receptor identified for quantitative analysis. The intake of a chemical is estimated from exposure models that combine various exposure factors related to behavior and physiology, such as exposure frequency and duration, contact rate, chemical concentration, body weight, and averaging time. Exposure is estimated by calculating the annual average daily dose (AADD) and lifetime average daily dose (LADD). The AADD and LADD both provide quantitative estimates of an individual’s daily exposure to a chemical. The difference between the two estimates is the time over which the exposure is averaged. Potential non-carcinogenic health effects are assumed to occur only after a threshold dose is reached; therefore, the AADD represents the average daily dose during the period of exposure. Conversely, potential carcinogenic health effects are considered to be non-threshold phenomena. Therefore, the LADD represents the average daily dose over a lifetime (i.e., the daily dose averaged over 70 years). The exposure parameters used in the risk evaluation are presented in Tables 3 and 4.

Except for exposure frequency, the exposure parameters are based primarily on conservative default values provided by Cal-EPA (1994) and U.S. EPA (1991). For the exposure frequency, the total days exposed (10 days/year equivalent to 160 hours/year), which is used for all receptors, was based on input from LEJ personnel and the number of hours students or school teachers would visit the Site. The estimated total days of exposure for the Living Classroom instructors is also 10 days/year (160 hours/year) because these receptors work at the Site when educational programs are planned. For the recreational user, it is not expected that they will use the site for more than 10 days/year (160 hours/year).


The RME exposure frequency for students and recreational user is based on the total days of exposure per year and was calculated as follows:

i. weekdays during the school calendar year: 4 hours/day x 18 weeks/year (every other week for a total school year of 36 weeks/year) x 1 day/week / 16 hours/day (hours awake);

ii. weekends during the school calendar year: 2 hours/day x 18 weeks/year (every other week for a total school year of 36 weeks/year) x 1 day/week / 16 hours/day (hours awake); and

iii. days during the summer months: 1 hour/day x 6.5 weeks/year (every other week for a summer duration of 13 weeks) x 1 day/week / 16 hours/day (hours awake).

The total days of exposure is the sum of each of these timeframes and is approximately 7 days/year rounded to 10 days/year (i.e., 160 hours/year).

4.3 TOXICITY ASSESSMENT Toxicity criteria adopted by the California Office of Environmental Health Hazard Assessment (OEHHA) within Cal-EPA were used for the COPCs to evaluate potential carcinogenic and noncarcinogenic health effects (Cal-EPA, 2003). The toxicity criteria for the COPCs are presented in Appendix D.

4.4 RISK CHARACTERIZATION Information from exposure and toxicity is used to quantitatively characterize potential risk. Health effects for non-carcinogens are quantified as a hazard index. Hazard indexes less than 1 generally are considered acceptable by U.S. EPA and Cal-EPA. Health effects for carcinogens are quantified as lifetime excess cancer risks. Carcinogenic risk within or below the range from 1x10-4 to 1x10-6 can be considered acceptable by regulatory agencies such as U.S. EPA and Cal-EPA.

Adolescent Student The potential noncancer hazard index and cancer risks associated with exposure to the chemicals in soil by an adolescent student are 0.01 and 2x10-7, respectively, and are summarized in Tables 5 and 6. These results indicate that exposure to chemicals in soil should


not result in unacceptable non-carcinogenic or carcinogenic health effects under the conditions evaluated. The supporting risk calculations are presented in Appendix D.

Recreational User The potential noncancer hazard index and cancer risks associated with exposure to the chemicals in soil by recreational user are 0.005 and 8x10-7, respectively, and are summarized in Tables 7 and 8. These results indicate that exposure to chemicals in soil should not result in unacceptable non-carcinogenic or carcinogenic health effects under the conditions evaluated. The supporting risk calculations are presented in Appendix D.

4.5 UNCERTAINTIES Quantifying uncertainty is an essential element of the risk evaluation process. Every step possible has been taken to limit uncertainties in this risk evaluation. However, risk assessment is an inherently uncertain process due to its predictive nature and reliance on assumptions that generally arises from a lack of knowledge of (1) site conditions and chemical distribution, (2) the accuracy of toxicity values used to quantify risks and health hazards to COPCs, and (3) the extent to which an individual will be exposed. This lack of knowledge means that assumptions must be made based on information presented in the scientific literature or professional judgment. Some of the assumptions used in this evaluation were selected in a manner that purposefully biases the process toward health conservatism. For example, for chemicals that were not detected in individual samples, it was assumed that one-half the SQL was representative of the concentration that may be present for purposes of calculating the 95% UCLs. This assumption may over- or underestimate the representative concentrations for chemicals that were detected infrequently in soil, but is more likely to overestimate the representative concentration.

One of the largest sources of uncertainty is associated with the limited understanding of the toxicity to humans from exposure to low concentrations generally encountered in the environment. The majority of the available toxicity data are from animal studies, which are then extrapolated using mathematical models or multiple uncertainty factors to predict what might occur in humans.

Current U.S. EPA guidance for risk assessment of chemical mixtures (U.S. EPA, 1989) recommends assuming an additive effect following exposure to multiple chemicals. Subsequent recommendations by other parties, such as the National Academy of Sciences (NRC, 1988) have also advocated a default assumption of additivity. As currently practiced,


risk assessments of chemical mixtures generally sum cancer risks regardless of tumor type and sum non-cancer hazard indices regardless of toxic endpoint or mode of action. Given the available experimental data, this approach likely overestimates potential risks associated with simultaneous exposure to multiple chemicals.

In summary, these and other assumptions contribute to the overall uncertainty in the risk assessment. Thus, it is believed that the risk evaluation results presented in this document are based on conservative estimates.

5.0 CONCLUSIONS

The results of the health risk evaluation indicate that, based on the intended use of the Site as an educational center and existing site conditions, potential exposures to chemicals in soil do not present an unacceptable human health risk to future adolescent students, teachers, or recreational users. The cumulative total estimated theoretical cancer risk, based on RME assumptions for exposures related to chemicals detected in soil, are less than the acceptable risk range of 1×10-6 to 1×10-4, and the cumulative total long-term chronic non-cancer hazard does not exceed a target hazard index (HI) of 1.0. The results of the risk evaluation are based on the planned site use as an educational center. A re-evaluation of potential human health risks at the Site may be required if Site use or conditions change significantly.

6.0 LIMITATIONS

Within the limitations of the agreed-upon scope of work, this assessment has been undertaken and performed in a professional manner in accordance with generally accepted practices, using the degree of skill and care ordinarily exercised by environmental consultants under similar circumstances. The conclusions presented herein are professional opinions based solely upon the analytical data described in this report. The results reported herein are applicable to the time the sampling occurred. They are intended exclusively for the purpose outlined herein and the Site location and project indicated. Due to physical limitations inherent to this or any environmental assessment, Geomatrix expressly does not warrant that the site is free of pollutants or that all pollutants have been identified. No other warranties, express or implied, are made.


7.0 REFERENCES

Cal-EPA, 1994, Preliminary Endangerment Assessment Guidance Manual, Department of Toxic Substances Control, January.

Cal-EPA, 2003, Office of Environmental Health Hazard Assessment (OEHHA), Toxicity Criteria Database. http://www.oehha.ca.gov/risk/ChemicalDB/index.asp

Geomatrix, 2003, Scope of Services and Cost Estimate – Heron’s Head Park – Pier 98

Geo/Resource Consultants, Inc., 1989. Data Compilation Report, Subchapter 15 Compliance Pier 98 Solid Waste Disposal Site. November.

Lawrence Berkeley National Laboratory (LBNL), 1995, Protocol for Detaining Background Concentrations in Metals in Soil at LBNL, August.

The Mark Group, 1989. Air Quality Solid Waste Assessment Test Report. Solid Waste Disposal Sites at Piers 94 and 98, Port of San Francisco, California. 88-01246.28. January 3, 1989.

RWQCB, 2003, Screening for Environmental Concerns at Sites With Contaminated Soil and Groundwater, Interim Final, July.

Tetra Tech, Inc, 1998. Soil Characterization Report and Management Plan, Pier 98. May 6, 1998.

United States Environmental Protection Agency (U.S. EPA), 1989, Risk Assessment Guidance for Superfund, Volume 1, Human Health Evaluation Manual, Part A, Interim Final: Office of Emergency and Remedial Response, Washington, D.C.

U.S. EPA, 1991, Human Health Evaluation Manual, Supplemental Guidance: “Standard Default Exposure Factors,” Office of Emergency and Remedial Response, Washington, D.C.

U.S. EPA, 1992, Supplemental Guidance to RAGS: Calculating the Concentration Term, Office of Solid Waste and Emergency Response, Washington, D.C.

TABLE 1

STATISTICAL SUMMARY OF ANALYTICAL RESULTS - METALS1

Heron's Head ParkSan Francisco, California

Concentrations reported in milligrams per kilogram (mg/kg)

Borehole DepthDate

Collected Arsenic Barium Cadmium Chromium Cobalt Copper Lead Mercury Molybdenum Nickel Vanadium ZincB-2-1.0 1 07/16/03 2.4 55 1.5 25 5.9 18 3.9 -0.050 -1.0 53 22 21B-3-1.0 1 07/16/03 7 48 3.1 160 41 19 63 0.330 1.3 780 24 51B-4-1.0 1 07/16/03 8 24 3.7 220 65 12 17 0.099 1.3 1200 17 34B-5-1.0 1 07/16/03 8.4 2.8 3.8 180 100 2.2 -1 -0.050 1.2 1600 2.4 14B-6-1.0 1 07/16/03 7.9 56 3.3 200 43 17 45 0.180 1.3 830 28 51B-7-1.0 1 07/16/03 7.7 64 3.2 200 39 21 41 0.270 1.3 740 24 74B-8-1.0 1 07/16/03 7.7 32 3.2 260 49 17 26 0.180 1.4 940 19 56B-9-1.0 1 07/16/03 7.4 7 3.3 300 74 4 -1 -0.050 1.1 1400 11 13B-10-1.0 1 07/16/03 5.4 76 2.2 100 13 19 140 0.150 1.2 140 34 73B-11-1.0 1 07/16/03 3.8 110 2.1 51 34 37 29 0.370 -1.0 76 34 30B-12-1.0 1 07/16/03 7.1 25 2.9 130 32 17 11 0.100 1.4 460 29 42B-13-1.0 1 07/16/03 4 64 1.8 47 8.1 13 24 0.150 1.0 47 32 32B-14-1.0 1 07/16/03 7 11 3 300 63 4.6 2.2 0.089 1.1 1200 13 14

Count (n) 13 13 13 13 13 13 13 13 13 13 13 13Number of Detects 13 13 13 13 13 13 11 10 11 13 13 13Number of Non-Detects 0 0 0 0 0 0 2 3 2 0 0 0Minimum Detection 2 3 2 25 6 2 2 0 1 47 2 13Maximum Detection 8 110 4 300 100 37 140 0 1 1600 34 74Minimum Detection Limit 0 0 0 0 0 0 1 0 1 0 0 0Maximum Detection Limit 0 0 0 0 0 0 1 0 1 0 0 0Mean (x) 6.45 44.22 2.85 167.15 43.62 15.45 31.01 0.15 1.12 728.15 22.26 38.85Standard Deviation (SD) 1.91 30.98 0.72 92.70 27.14 9.02 37.97 0.11 0.30 538.35 9.58 21.16Student T Value (t) 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.7895% upper confidence limit (UCL) 7.39 59.53 3.21 212.97 57.03 19.91 49.78 0.21 1.27 994.27 26.99 49.30Maximum 8 110 4 300 100 37 140 0.37 1 1600 34 74Representative Background2 14 358.8 1.5 91.4 22 59.6 14.7 0.3 3.2 120 78.2 91.5Residential ESLs3 5.5 750 7.8 750 40 230 200 2.5 40 150 110 600Chemical of Potential Concern ? no no no no yes no no no no yes no no

NA NA NA NA 57 NA NA NA NA 994 NA NA

Notes:1 Samples collected by Geomatrix Consultants, Inc. and analyzed by STL San Francisco of Pleasanton, California for metals using Environmental Protection Agency (EPA) Methods 6010B and 7471A (mercury). Only detected metal analytes are shown. For a complete list of analytes, refer to the laboratory reports.2 Regional background concentrations obtained from Lawrence Berkeley National Laboratory, 1995.3

4 If the 95% UCL is higher than maximum detected concentration, the representative concentrations were based on maximum detected concentrations. 95% UCL of mean = x +stdev*t/n^0.5 "<1.0" = denotes that the chemical was not detected above the laboratory sample quantitation limit

Exposure Point Concentration 4

San Francisco Regional Water Quality Control Board, Environmental Screening Levels - Residential Land Use (shallow soil where groundwater is a current or potential drinking water resource. Environmental Screening Levels at Sites with Contaminated Soil and Groundwater (Interim Final, July 2003). The Cadmium ESL is based on a noncarcinogenic endpoint because the California cancer toxicity factor has been withdrawn (U.S. EPA Region 9 PRG update 02/10/03 http://www.epa.gov/Region9/waste/sfund/prg/revised02.htm). The Chromium ESL is based on chromium III.

I:\Doc_Safe\8000s\8621.003\Report\Data table 2003_Tbl_1_Repcons.xls

TABLE 2

STATISTICAL SUMMARY OF ANALYTICAL RESULTS - PAH's1


Concentrations reported in micrograms per kilogram (µg/kg)

Borehole DepthSample

Date Acenapthy Acene Anthra B(a)A B(b)F B(k)F B(a)P Chry B(g,h,i)P Di(a,h)A Fluo Fluorene Indeno Napth Phen PyreneB-2-1.0 1 7/16/03 -630 -630 -630 -630 -630 -630 -630 -630 -630 -630 -630 -630 -630 -630 -630 -630B-3-1.0 1 7/16/03 50 -10 28 190 310 220 390 270 820 110 530 -10 430 18 210 760B-4-1.0 1 7/16/03 130 -25 50 380 720 120 820 570 2000 120 1300 -25 53 52 550 2100B-5-1.0 1 7/16/03 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5B-6-1.0 1 7/16/03 81 -25 37 250 520 460 530 370 1200 130 840 -25 670 29 380 1100B-7-1.0 1 7/16/03 160 -10 77 430 730 470 940 590 2000 230 1300 -10 1000 64 550 2000B-8-1.0 1 7/16/03 21 110 270 580 360 400 540 590 660 230 1000 130 400 16 1500 1700B-9-1.0 1 7/16/03 -5 -5 -5 11 8 8 8 9 8 -5 21 -5 6 -5 9 19

B-10-1.0 1 7/16/03 -5 -5 -5 26 39 24 34 38 55 15 40 -5 31 -5 22 57B-11-1.0 1 7/16/03 -130 -130 -130 -130 -130 -130 -130 -130 -130 -130 -130 -130 -130 -130 -130 -130B-12-1.0 1 7/16/03 190 -50 130 640 1300 650 1500 870 3000 320 2200 -50 1600 65 760 3400B-13-1.0 1 7/16/03 -5 -5 6 30 33 27 34 38 45 16 45 -5 28 5 19 55B-14-1.0 1 7/16/03 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5 -5

Count (n) 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13 13Number of Detects 6 1 7 9 9 9 9 9 9 8 9 1 9 7 9 9Number of Non-Detects 7 12 6 4 4 4 4 4 4 5 4 12 4 6 4 4Minimum Detection 21 110 6 11 8 8 8 9 8 15 21 130 6 5 9 19Maximum Detection 190 110 270 640 1300 650 1500 870 3000 320 2200 130 1600 65 1500 3400Minimum Detection Limit 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5Maximum Detection Limit 630 630 630 630 630 630 630 630 630 630 630 630 630 630 630 630Mean (x) 78.81 43.27 75.98 224.77 338.87 212.58 398.52 286.95 782.54 119.88 589.31 44.81 354.04 49.15 337.32 890.46Standard Deviation (SD) 96.11 87.67 103.62 227.72 392.72 222.70 462.94 292.10 987.24 118.57 695.18 89.10 485.83 83.93 432.66 1097.33Student T Value (t) 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.78 1.7895% upper confidence limit 126.32 86.61 127.20 337.34 533.00 322.67 627.36 431.33 1270.55 178.50 932.95 88.85 594.19 90.64 551.19 1432.89Maximum 190 110 270 640 1300 650 1500 870 3000 320 2200 130 1600 65 1500 3400Residential ESLs2 13000 16000 2800 380 380 380 38 3800 27000 110 40000 8900 380 4200 11000 85000

no no no yes yes yes yes no no yes no no yes no no no337 533 323 627 178 594

Notes:1 Samples collected by Geomatrix Consultants, Inc. and analyzed by STL San Francisco of Pleasanton, California for polynuclear aromatic hydrocarbons (PAHs) using Environmental Protection Agency (EPA) Method 8270C selective ion monitoring (SIM).2 San Francisco Regional Water Quality Control Board, Environmental Screening Levels - Residential Land Use (shallow soil where groundwater is a current or potential drinking water resource. Environmental Screening Levels at Sites with Contaminated Soil and Groundwater (Interim Final, July 2003).3 If the 95% UCL is higher than maximum detected concentration, the representative concentrations were based on maximum detected concentrations.

95% UCL of mean = x +stdev*t/n^0.5"<5.0" = denotes that the chemical was not detected above the laboratory sample quantitation limit

Abbreviations:

Chemical of Potential Concern ?Exposure Point Concentration 3

Acenapthy (Acenaphthylene), Acen (Acenaphthene), Anthra (Anthracene), B(a)A (Benzo(a)anthracene), B(a)P (Benzo(a)Pyrene, B(b)F (Benzo(b)fluoranthene), B(k)F (Benzo(k)fluoranthene), B(g,h,i)P (Benzo(g,h,i)perylene, Chry (Chrysene), Di(a,h)A Di(a,h)anthracene, Fluo (Fluoranthene), Indeno (Indeno(1,2,3-c,d)pyrene), Napth (Napthalane), Phen (Phenanthrene)

I:\Doc_Safe\8000s\8621.003\Report\Data table 2003_Tbl_1_Repcons.xls

TABLE 3

EXPOSURE PARAMETERS FOR ADOLESCENT STUDENTS


I:\Doc_Safe\8000s\8621.003\Report\Exp Param_ Youth.doc Page 1 of 2

Exposure Parameter Units Reasonable Maximum Exposure

GENERAL EXPOSURE PARAMETERS

Exposure Frequency (EF) days/year Value: 10

Rationale: Please refer to text

Exposure Duration (ED) years Value: 11

Rationale: Based on the definition of a youth as an individual from 7 to 17 years of age; Cal-EPA, 1992, Chapter 8, Appendix 13

Body Weight (BW) kg Value: 44

Rationale: Mean of fiftieth percentile values for 7- to 17-year-old males and females; Cal-EPA, 1992, Chapter 8, Appendix 13

Averaging Time (AT) days Value: 25,550 (carcinogens) 4,015 (noncarcinogens)

Rationale: Cal-EPA, 1992; U.S. EPA, 1991

Pathway-Specific Parameters

Incidental Soil Ingestion

Soil Ingestion Rate (IRs) mg/day Value: 100

Rationale: Value for individuals greater than 6 years of age; Cal-EPA, 1992; U.S. EPA, 1991

Dermal Contact with Soil

Exposed Skin Surface Area (SAs) cm2/day Value: 4,300

Rationale: Average of exposed skin surface area (head, hands, forearms, lower legs) of 5700 cm2/day for an adult and 2800 cm2/day for a child less than 6 years old; U.S. EPA, 2001

Soil-to-Skin Adherence Factor (SAF) mg/cm2 Value: 0.2

Rationale: U.S. EPA, 2001

Absorption Fraction (ABS) unitless Value: Chemical-specific

TABLE 3

EXPOSURE PARAMETERS FOR ADOLESCENT STUDENTS


I:\Doc_Safe\8000s\8621.003\Report\Exp Param_ Youth.doc Page 2 of 2


Inhalation of Suspended Soil Particulates

Inhalation Rate (IHRa) m3/hr Value: 1.6


Particulate Emission Factor (PEF) m3/kg Value: 1.3x109


Exposure Time (ET) hours Value: 24

Rationale: Basis for 10-day exposure frequency

TABLE 4

EXPOSURE PARAMETERS FOR RECREATIONAL USER (CHILD/ADULT)


I:\Doc_Safe\8000s\8621.003\Report\Exp Param_Adult visitor.doc


GENERAL EXPOSURE PARAMETERS


Rationale: Please refer to text

Exposure Duration (ED) years Value: 6 (child) 24 (adult)


Body Weight (BW) kg Value: 15 (child) 70 (adult)


Averaging Time (AT) days Value: 25,550 (carcinogens) 2,190 (child-noncarcinogens) 8,760 (adult-noncarcinogens)


Incidental Soil Ingestion

Soil Ingestion Rate (IRs) mg/day Value: 200 (child) 100 (adult)





Exposed Skin Surface Area (SAs) cm2/day Value: 2,800 (child) 5,700 (adult)


Soil-to-Skin Adherence Factor (SAF) mg/cm2 Value: 0.2 (child) 0.07 (adult)

Absorption Fraction (ABS) unitless Value: Chemical-specific

Inhalation of Suspended Soil Particulates

Inhalation Rate (IHRa) m3/hr Value: 0.42 (child) 0.83 (adult)


Particulate Emission Factor (PEF) m3/kg Value: 1.3x109


Exposure Time (ET) hours Value: 24

Rationale: Basis for 10-day exposure frequency

TABLE 5

SUMMARY OF NONCARCINOGENIC HAZARD INDICES: ADOLESCENT STUDENTS


Soil

Incidental Ingestion of

Soil

Dermal Contact with

Soil Inhalation of Particulates

Percent Contribution

Benzo(a)anthracene NA NA NA NA NABenzo(a)pyrene NA NA NA NA NABenzo(b)fluoranthene NA NA NA NA NABenzo(k)fluoranthene NA NA NA NA NACobalt 1.8E-04 1.5E-05 6.5E-04 2.E-04 5.4%Dibenz(a,h)anthracene NA NA NA NA NAIndeno(1,2,3-cd)pyrene NA NA NA NA NANickel 3.1E-03 2.7E-04 3.2E-06 3.E-03 94.6%Total 3.3E-03 2.8E-04 6.6E-04 4.E-03 100.0%Percent Contribution 92.1% 7.9% 18.4%NA = not applicable

ChemicalHazard Index

I:\Doc_Safe\8000s\8621.003\Report\risk workbook.xls

TABLE 6

SUMMARY OF EXCESS LIFETIME CANCER RISKS: ADOLESCENT STUDENTS


Soil

Incidental Ingestion of

Soil

Dermal Contact with



Benzo(a)anthracene 4.0E-09 5.1E-09 1.3E-12 9.E-09 3.9%Benzo(a)pyrene 7.4E-08 9.5E-08 2.5E-11 2.E-07 72.4%Benzo(b)fluoranthene 6.2E-09 8.1E-09 2.1E-12 1.E-08 6.1%Benzo(k)fluoranthene 3.8E-09 4.9E-09 1.3E-12 9.E-09 3.7%Cobalt NA NA NA NA NADibenz(a,h)anthracene 7.1E-09 9.2E-09 7.5E-12 2.E-08 7.0%Indeno(1,2,3-cd)pyrene 7.0E-09 9.0E-09 2.4E-12 2.E-08 6.9%Nickel NA NA 9.3E-09 NA NATotal 1.0E-07 1.3E-07 9.3E-09 2.E-07 100.0%Percent Contribution 43.7% 56.3% 4.0%

ChemicalExcess

Cancer Risk


TABLE 7

SUMMARY OF NONCARCINOGENIC HAZARD INDICES: RECREATIONAL USER (CHILD/ADULT)


Soil

Chemical Incidental Ingestion of Soil


Inhalation of Particulates Hazard Index


Benzo(a)anthracene NA NA NA NA NABenzo(a)pyrene NA NA NA NA NABenzo(b)fluoranthene NA NA NA NA NABenzo(k)fluoranthene NA NA NA NA NACobalt 1.1E-04 6.4E-06 5.9E-05 1.8E-04 7.9%Dibenz(a,h)anthracene NA NA NA NA NAIndeno(1,2,3-cd)pyrene NA NA NA NA NANickel 1.9E-03 1.1E-04 2.9E-07 2.1E-03 92.1%Total 2E-03 1E-04 6E-05 2E-03 100.0%Percent Contribution 92% 5% 3% 100%NA = Not Applicable


Soil

Incidental Ingestion of Soil

Dermal Contact with



Benzo(a)anthracene 1.3E-08 5.3E-09 1.6E-13 1.8E-08 4%Benzo(a)pyrene 2.4E-07 9.9E-08 2.9E-12 3.3E-07 72%Benzo(b)fluoranthene 2.0E-08 8.4E-09 2.5E-13 2.8E-08 6%Benzo(k)fluoranthene 1.2E-08 5.1E-09 1.5E-13 1.7E-08 4%Cobalt NA NA NA NA NADibenz(a,h)anthracene 2.3E-08 9.6E-09 8.7E-13 3.2E-08 7%Indeno(1,2,3-cd)pyrene 2.2E-08 9.4E-09 2.8E-13 3.2E-08 7%Nickel NA NA 1.1E-09 1.1E-09 0%Total 3.3E-07 1.4E-07 1.1E-09 4.6E-07 100%Percent Contribution 70% 30% 0%

TABLE 8

SUMMARY OF EXCESS LIFETIME CANCER RISKS: RECREATIONAL USER (CHILD/ADULT)


Chemical Excess Cancer Risk -

Child

Page 1 of 2I:\Doc_Safe\8000s\8621.003\Report\risk workbook.xls

Soil


Dermal Contact with



Benzo(a)anthracene 6.8E-09 5.8E-09 3.3E-13 1.3E-08 1.8E-08 3.1E-08 4%Benzo(a)pyrene 1.3E-07 1.1E-07 6.2E-12 2.3E-07 3.3E-07 5.7E-07 72%Benzo(b)fluoranthene 1.1E-08 9.2E-09 5.3E-13 2.0E-08 2.8E-08 4.8E-08 6%Benzo(k)fluoranthene 6.5E-09 5.5E-09 3.2E-13 1.2E-08 1.7E-08 2.9E-08 4%Cobalt NA NA NA NA NA NA NADibenz(a,h)anthracene 1.2E-08 1.0E-08 1.8E-12 2.3E-08 3.2E-08 5.5E-08 7%Indeno(1,2,3-cd)pyrene 1.2E-08 1.0E-08 5.9E-13 2.2E-08 3.2E-08 5.4E-08 7%Nickel NA NA 2.3E-09 2.3E-09 1.1E-09 3.4E-09 0%Total 1.7E-07 1.5E-07 2.3E-09 3.3E-07 4.6E-07 7.9E-07 100%Percent Contribution 54% 46% 1%

Excess Cancer Risk -

Total


Adult


Child

TABLE 8

SUMMARY OF EXCESS LIFETIME CANCER RISKS: RECREATIONAL USER (CHILD/ADULT)



8621.003

1

S IT E LOC AT ION MAPP ier 98

Heron's Head P arkS an F rancisco, C alifornia

S:\

86

00

\86

21

\86

21

.00

3\_

fig_

01

(02

).a

i

S IT E

B ase map from T he T homas G uide, 1997 G olden G ate S treet G uide and Directory. R eproduced with permiss ion granted by T HOMAS B R OS . MAP S ® . T his map is copyrighted by T HOMAS B R OS . MAP S ® . It is unlawful to copy or reproduce all or any part thereof, whether for personal use or resale, without permiss ion. All rights reserved.

0 2400 F eet

P roject No.

F igure

Appendix A

Boring and Right-of-Entry Permits

Appendix B

Boring Logs

Appendix C

Laboratory Analytical Reports and Chain-of-Custody Records

Appendix D

Supporting Risk Calculations

APPENDIX DHUMAN HEALTH RISK ASSESSMENT CALCULATIONSHeron's Head ParkSan Francisco, CaliforniaProject # 8621.003FINAL

RISK EQUATIONS

INCIDENTAL INGESTION OF SOIL/SEDIMENTAADD = (Cs x IRs x ABSos x EFig x ED x CFmg-kg) Hazard Quotient = AADD

(BW x ATnc) RfDo

LADD = (Cs x IRs x ABSos x EFig x ED x CFmg-kg) Excess Cancer Risk = LADD x SFo(BW x ATca)

DERMAL CONTACT WITH SOIL/SEDIMENTAADD = (Cs x SAs x SAF x ABSds x EFdc x ED x CFmg-kg) Hazard Quotient = AADD

(BW x ATnc) RfDo

LADD = (Cs x SAs x SAF x ABSds x EFdc x ED x CFmg-kg) Excess Cancer Risk = LADD x SFo(BW x ATca)

INHALATION OF RESUSPENDED SOIL PARTICULATESAADD = (Cs x IHRaa x ETaa x ABSip x EFaa x ED) Hazard Quotient = AADD

(BW x PEF x ATnc) RfDi

LADD = (Cs x IHRaa x ETaa x ABSip x EFaa x ED) Excess Cancer Risk = LADD x SFi(BW x PEF x ATca)



EXPOSURE PARAMETERS

Parameter Symbol Units Adult Child Adolecent Students

ALL PATHWAYSExposure Frequency EF d/yr 10 10 10Exposure Duration ED yr 30 6 11Body Weight BW kg 70 15 44Averaging Time-Non-cancer ATnc days 10,950 2,190 4,015Averaging Time-Cancer ATca days 25,550 25,550 25,550INCIDENTAL INGESTION OF SOIL/SEDIMENTExposure Frequency EFig d/yr 10 10 10Ingestion Rate IRs mg/d 100 200 100DERMAL CONTACT WITH SOIL/SEDIMENTExposure Frequency EFdc d/yr 10 10 10Surface Area SAs cm2 5,700 2,800 4,300Soil-to-Skin Adherence Factor SAF mg/cm2 0.1 0.2 0.2INHALATION OF RESUSPENDED SOIL PARTICULATESExposure Frequency EFpe d/yr 10 10 10Inhalation Rate IHRpe m3/hr 0.83 0.42 1.6Exposure Time ETpe hr/d 24 24 24

I:\Project\8000s\8621.003\Report\risk workbook.xls Page 2 of 22


REPRESENTATIVE CONCENTRATION

Chemical

EPC

(mg/kg)Benzo(a)anthracene 0.34Benzo(a)pyrene 0.63Benzo(b)fluoranthene 0.53Benzo(k)fluoranthene 0.32Cobalt 57Dibenz(a,h)anthracene 0.18Indeno(1,2,3-cd)pyrene 0.59Nickel 994



TOXICITY CRITERIA

Reference Doses (RfD)

oral dermal inhalation chronic oral chronic dermal

chronic inhalation subchronic oral subchronic

inhalation

SFo SFd SFi RfDo RfDd RfDi sRfDo sRfDi(mg/kg-d)-1 (mg/kg-d)-1 (mg/kg-d)-1 (mg/kg-d) (mg/kg-d) (mg/kg-d) (mg/kg-d) (mg/kg-d)

Benzo(a)anthracene 1.2 1.2 0.39 NA NA NA NA NABenzo(a)pyrene 12 12 3.9 NA NA NA NA NABenzo(b)fluoranthene 1.2 1.2 0.39 NA NA NA NA NABenzo(k)fluoranthene 1.2 1.2 0.39 NA NA NA NA NACobalt NC NC NC 0.02 0.02 5.70E-06 NA NADibenz(a,h)anthracene 4.1 4.1 4.1 NA NA NA NA NAIndeno(1,2,3-cd)pyrene 1.2 1.2 0.39 NA NA NA NA NANickel NC NC 0.91 0.02 0.02 0.02 NA NANA = Not Available; NC = Non Carcinogen

Slope Factors (SF)

Chemical



ABSORPTION FACTORS

Oral soil Oral Water Oral Produce

Inhalation VOC

Inhalation Dust Dermal Soil Permeability

Constant

Steady-state Time

ABSos ABSow ABSop ABSiv ABSip ABSds Kp (USEPA) t* (USEPA)(--) (--) (--) (--) (--) (--) (cm/hr) (hr)

Benzo(a)anthracene 1 1 1 1 1 0.15 0.47 8.53Benzo(a)pyrene 1 1 1 1 1 0.15 0.7 11.67Benzo(b)fluoranthene 1 1 1 1 1 0.15 0.7 12.03Benzo(k)fluoranthene 1 1 1 1 1 0.15 NA NACobalt 1 1 1 1 1 0.01 0.001 NADibenz(a,h)anthracene 1 1 1 1 1 0.15 1.5 17.57Indeno(1,2,3-cd)pyrene 1 1 1 1 1 0.15 1 16.83Nickel 1 1 1 1 1 0.01 0.0002 NANA = Not Available

Chemical



PHYSICOCHEMICAL PROPERTIES

Chemical

Log Octanol Water

Partition Coefficient (log Kow)

Henry's Law Constant (H)

Henry's Law Constant

(H')

Aqueous Solubility (S)

Diffusivity in Water (Dw)

Organic Carbon

Partition Coefficient

(Koc)

Molecular Weight (MW) VOC?

(--) (atm-m3/mole) (unitless) (mg/l)given

(cm2/sec)calculated(cm2/sec) (cm2/sec) (l/kg) (g/mole)

Benzo(a)anthracene 5.70 3.35E-06 1.37E-04 9.40E-03 5.10E-02 NA 9.00E-06 3.98E+05 228.30 NoBenzo(a)pyrene 6.11 1.13E-06 4.63E-05 1.62E-03 4.30E-02 NA 9.00E-06 1.02E+06 252.32 NoBenzo(b)fluoranthene 6.20 1.11E-04 4.55E-03 1.50E-03 2.26E-02 NA 5.56E-06 1.23E+06 252.32 NoBenzo(k)fluoranthene 6.20 8.29E-07 3.40E-05 8.00E-04 2.26E-02 NA 5.56E-06 1.23E+06 252.32 NoCobalt NA NA NA NA NA NA NA NA 87.62 NADibenz(a,h)anthracene 6.69 1.47E-08 6.03E-07 2.49E-03 2.02E-02 NA 5.18E-06 3.80E+06 278.36 NoIndeno(1,2,3-cd)pyrene 6.65 1.60E-06 6.56E-05 2.20E-05 1.90E-02 NA 5.66E-06 3.47E+06 276.34 NoNickel NA NA NA NA NA NA NA NA 59.00 NA

H' = H / RT

Diffusivity in Air (Di)



PARTICULATE EMISSION FACTOR (PEF)

Source Scenario

Q/C(g/m2-sec) per

(kg/m3)

PEF(mg/kg) per

(mg/m3) Soil Residential 1.30E+09 1.30E+09

PEF = Q/C x 36000.036 x (1 - V) x (Um/Ut)3 x F(x)

Source: USEPA, 1996

Symbol Value Units Source(s)Q/C see above g/m2-sec per kg/m3 estimatedV 0.5 -- site-specific

Um 4.69 m/sec USEPA, 1996Ut 11.32 m/sec USEPA, 1996

F(x) 2.E-01 -- USEPA, 1996Equivalent Threshold Value of Windspeed at 7 mFunction of Um/Ut

ParameterInverse of Dispersion FactorFraction of Vegetative CoverMean Annual Windspeed



INCIDENTAL INGESTION OF SOIL: ADULT

Chemical Concentration Soil (Cs)

Oral Absorption Factor-Soil

(ABSos)

Annual Average Daily Dose (AADD)

Oral Chronic Reference

Dose (RfDo)

Hazard Quotient

Lifetime Average

Daily Dose (LADD)

Oral Slope Factor (SFo)

Excess Cancer Risk

(mg/kg) (--) (mg/kg-d) (mg/kg-d) (--) (mg/kg-d) (mg/kg-d)-1 (--)Benzo(a)anthracene 0.337 1 1.3E-08 NA NA 5.7E-09 1.2 6.8E-09Benzo(a)pyrene 0.627 1 2.5E-08 NA NA 1.1E-08 12 1.3E-07Benzo(b)fluoranthene 0.532 1 2.1E-08 NA NA 8.9E-09 1.2 1.1E-08Benzo(k)fluoranthene 0.322 1 1.3E-08 NA NA 5.4E-09 1.2 6.5E-09Cobalt 57 1 2.2E-06 0.02 1.1E-04 9.6E-07 NC NADibenz(a,h)anthracene 0.178 1 7.0E-09 NA NA 3.0E-09 4.1 1.2E-08Indeno(1,2,3-cd)pyrene 0.594 1 2.3E-08 NA NA 1.0E-08 1.2 1.2E-08Nickel 994 1 3.9E-05 0.02 1.9E-03 1.7E-05 NC NA

2E-03 2E-07

AADD = (Cs x IRs x ABSos x EFig x ED x CFmg-kg) Hazard Quotient = AADD(BW x ATnc) RfDo


Parameter Symbol Values UnitsExposure Frequency EFig 10 d/yrExposure Duration ED 30 yrBody Weight BW 70 kgAveraging Time-Non-cancer ATnc 10,950 daysAveraging Time-Cancer ATca 25,550 daysIngestion Rate IRs 100 mg/dConversion Factor from mg to kg CFmg-kg 1E-06 kg/mg

NA = Not Applicable



DERMAL CONTACT WITH SOIL: ADULT


Dermal Absorption Factor-Soil

(ABSds)


Dermal Chronic

Reference Dose (RfDd)

Hazard Quotient

Lifetime Average

Daily Dose (LADD)

Dermal Slope Factor (SFd)

Excess Cancer Risk

(mg/kg) (--) (mg/kg-d) (mg/kg-d) (--) (mg/kg-d) (mg/kg-d)-1 (--)Benzo(a)anthracene 0.337 0.15 1.1E-08 NA NA 4.8E-09 1.2 5.8E-09Benzo(a)pyrene 0.627 0.15 2.1E-08 NA NA 9.0E-09 12 1.1E-07Benzo(b)fluoranthene 0.532 0.15 1.8E-08 NA NA 7.6E-09 1.2 9.2E-09Benzo(k)fluoranthene 0.322 0.15 1.1E-08 NA NA 4.6E-09 1.2 5.5E-09Cobalt 57 0.01 1.3E-07 0.02 6.4E-06 5.4E-08 NC NADibenz(a,h)anthracene 0.178 0.15 6.0E-09 NA NA 2.6E-09 4.1 1.0E-08Indeno(1,2,3-cd)pyrene 0.594 0.15 2.0E-08 NA NA 8.5E-09 1.2 1.0E-08Nickel 994 0.01 2.2E-06 0.02 1.1E-04 9.5E-07 NC NA

1E-04 1E-07

AADD = (Cs x SAs x SAF x ABSds x EFdc x ED x CFmg-kg) Hazard Quotient = AADD(BW x ATnc) RfDo


Parameter Symbol Values UnitsExposure Frequency EFdc 10 d/yrExposure Duration ED 30 yrBody Weight BW 70 kgAveraging Time-Non-cancer ATnc 10,950 daysAveraging Time-Cancer ATca 25,550 daysSurface Area SAs 5,700 cm2

Soil-to-Skin Adherence Factor SAF 0.1 mg/cm2

Conversion Factor from mg to kg CFmg-kg 1E-06 kg/mg

NA = Not Applicable



INHALATION OF RESUSPENDED PARTICULATES FROM SOIL: ADULT


Inhalation Absorption

Factor-Dusts (ABSip)

Annual Average

Daily Dose (AADD)

Inhalation Chronic

Reference Dose (RfDi)

Hazard Quotient

Lifetime Average Daily Dose (LADD)

Inhalation Slope Factor

(SFi)

Excess Cancer Risk

(mg/kg) (--) (mg/kg-d) (mg/kg-d) (--) (mg/kg-d) (mg/kg-d)-1 (--)Benzo(a)anthracene 3.37E-01 1 2.0E-12 NA NA 8.5E-13 0.39 3.3E-13Benzo(a)pyrene 6.27E-01 1 3.7E-12 NA NA 1.6E-12 3.9 6.2E-12Benzo(b)fluoranthene 5.32E-01 1 3.1E-12 NA NA 1.3E-12 0.39 5.3E-13Benzo(k)fluoranthene 3.22E-01 1 1.9E-12 NA NA 8.2E-13 0.39 3.2E-13Cobalt 5.70E+01 1 3.4E-10 0.0000057 5.9E-05 1.4E-10 NC NADibenz(a,h)anthracene 1.78E-01 1 1.1E-12 NA NA 4.5E-13 4.1 1.8E-12Indeno(1,2,3-cd)pyrene 5.94E-01 1 3.5E-12 NA NA 1.5E-12 0.39 5.9E-13Nickel 9.94E+02 1 5.9E-09 0.02 2.9E-07 2.5E-09 0.91 2.3E-09

6E-05 2E-09

AADD = (Cs x IHRaa x ETaa x ABSip x EFaa x ED) Hazard Quotient = AADD(BW x PEF x ATnc) RfDi


Parameter Symbol Units ValuesExposure Frequency EFpe d/yr 10Exposure Duration ED yr 30Body Weight BW kg 70Averaging Time-Non-cancer ATnc days 10,950Averaging Time-Cancer ATca days 25,550Inhalation Rate IHRpe m3/hr 0.83Exposure Time ETpe hr/d 24Particulate Emission Factor PEF m3/kg 1.32E+09

NA = Not Applicable



SUMMARY NON-CANCER RISK CHARACTERIZATION: ADULT

ADULT RECREATIONAL USER




Benzo(a)anthracene NA NA NA NABenzo(a)pyrene NA NA NA NABenzo(b)fluoranthene NA NA NA NABenzo(k)fluoranthene NA NA NA NACobalt 1.1E-04 6.4E-06 5.9E-05 1.8E-04Dibenz(a,h)anthracene NA NA NA NAIndeno(1,2,3-cd)pyrene NA NA NA NANickel 1.9E-03 1.1E-04 2.9E-07 2.1E-03Total 2.1E-03 1.2E-04 5.9E-05 2.2E-03

NA = Not Applicable



INCIDENTAL INGESTION OF SOIL: CHILD



(ABSos)



Dose (RfDo)

Hazard Quotient

Lifetime Average

Daily Dose (LADD)


Excess Cancer Risk

(mg/kg) (--) (mg/kg-d) (mg/kg-d) (--) (mg/kg-d) (mg/kg-d)-1 (--)Benzo(a)anthracene 0.337 1 1.2E-07 NA NA 1.1E-08 1.2 1.3E-08Benzo(a)pyrene 0.627 1 2.3E-07 NA NA 2.0E-08 12 2.4E-07Benzo(b)fluoranthene 0.532 1 1.9E-07 NA NA 1.7E-08 1.2 2.0E-08Benzo(k)fluoranthene 0.322 1 1.2E-07 NA NA 1.0E-08 1.2 1.2E-08Cobalt 57 1 2.1E-05 0.02 1.0E-03 1.8E-06 NC NADibenz(a,h)anthracene 0.178 1 6.5E-08 NA NA 5.6E-09 4.1 2.3E-08Indeno(1,2,3-cd)pyrene 0.594 1 2.2E-07 NA NA 1.9E-08 1.2 2.2E-08Nickel 994 1 3.6E-04 0.02 1.8E-02 3.1E-05 NC NA

2E-02 3E-07




NA = Not Applicable



DERMAL CONTACT WITH SOIL: CHILD



(ABSds)


Dermal Chronic


Hazard Quotient

Lifetime Average

Daily Dose (LADD)


Excess Cancer Risk

(mg/kg) (--) (mg/kg-d) (mg/kg-d) (--) (mg/kg-d) (mg/kg-d)-1 (--)Benzo(a)anthracene 0.337 0.15 5.2E-08 NA NA 4.4E-09 1.2 5.3E-09Benzo(a)pyrene 0.627 0.15 9.6E-08 NA NA 8.2E-09 12 9.9E-08Benzo(b)fluoranthene 0.532 0.15 8.2E-08 NA NA 7.0E-09 1.2 8.4E-09Benzo(k)fluoranthene 0.322 0.15 4.9E-08 NA NA 4.2E-09 1.2 5.1E-09Cobalt 57 0.01 5.8E-07 0.02 2.9E-05 5.0E-08 NC NADibenz(a,h)anthracene 0.178 0.15 2.7E-08 NA NA 2.3E-09 4.1 9.6E-09Indeno(1,2,3-cd)pyrene 0.594 0.15 9.1E-08 NA NA 7.8E-09 1.2 9.4E-09Nickel 994 0.01 1.0E-05 0.02 5.1E-04 8.7E-07 NC NA

5E-04 1E-07






NA = Not Applicable



INHALATION OF RESUSPENDED PARTICULATES FROM SOIL: CHILD




Annual Average

Daily Dose (AADD)

Inhalation Chronic


Hazard Quotient



(SFi)

Excess Cancer Risk


1E-04 1E-09




NA = Not Applicable



SUMMARY NON-CANCER RISK CHARACTERIZATION: CHILD

Child Recreational User




Benzo(a)anthracene NA NA NA NABenzo(a)pyrene NA NA NA NABenzo(b)fluoranthene NA NA NA NABenzo(k)fluoranthene NA NA NA NACobalt 1.0E-03 2.9E-05 1.4E-04 1.2E-03Dibenz(a,h)anthracene NA NA NA NAIndeno(1,2,3-cd)pyrene NA NA NA NANickel 1.8E-02 5.1E-04 6.9E-07 1.9E-02Total 1.9E-02 5.4E-04 1.4E-04 2.0E-02

NA = Not Applicable



SUMMARY CARCINOGENIC RISK CHARACTERIZATION: CHILD AND ADULT

Child


Dermal Contact with


Benzo(a)anthracene 1.3E-08 5.3E-09 1.6E-13 1.8E-08Benzo(a)pyrene 2.4E-07 9.9E-08 2.9E-12 3.3E-07Benzo(b)fluoranthene 2.0E-08 8.4E-09 2.5E-13 2.8E-08Benzo(k)fluoranthene 1.2E-08 5.1E-09 1.5E-13 1.7E-08Cobalt NA NA NA NADibenz(a,h)anthracene 2.3E-08 9.6E-09 8.7E-13 3.2E-08Indeno(1,2,3-cd)pyrene 2.2E-08 9.4E-09 2.8E-13 3.2E-08Nickel NA NA 1.1E-09 1.1E-09Total 3.3E-07 1.4E-07 1.1E-09 4.6E-07NA = Not Applicable


Child



SUMMARY CARCINOGENIC RISK CHARACTERIZATION: CHILD AND ADULT

Adult


Dermal Contact with


Benzo(a)anthracene 6.8E-09 5.8E-09 3.3E-13 1.3E-08 3.1E-08Benzo(a)pyrene 1.3E-07 1.1E-07 6.2E-12 2.3E-07 5.7E-07Benzo(b)fluoranthene 1.1E-08 9.2E-09 5.3E-13 2.0E-08 4.8E-08Benzo(k)fluoranthene 6.5E-09 5.5E-09 3.2E-13 1.2E-08 2.9E-08Cobalt NA NA NA NA NADibenz(a,h)anthracene 1.2E-08 1.0E-08 1.8E-12 2.3E-08 5.5E-08Indeno(1,2,3-cd)pyrene 1.2E-08 1.0E-08 5.9E-13 2.2E-08 5.4E-08Nickel NA NA 2.3E-09 2.3E-09 3.4E-09Total 1.7E-07 1.5E-07 2.3E-09 3.3E-07 7.9E-07NA = Not Applicable


Total


Adult



INCIDENTAL INGESTION OF SOIL: ADOLESCENT STUDENT



(ABSos)



Dose (RfDo)

Hazard Quotient

Lifetime Average

Daily Dose (LADD)


Excess Cancer Risk

(mg/kg) (--) (mg/kg-d) (mg/kg-d) (--) (mg/kg-d) (mg/kg-d)-1 (--)Benzo(a)anthracene 3.37E-01 1 2.1E-08 NA NA 3.3E-09 1.2 4.0E-09Benzo(a)pyrene 6.27E-01 1 3.9E-08 NA NA 6.1E-09 12 7.4E-08Benzo(b)fluoranthene 5.32E-01 1 3.3E-08 NA NA 5.2E-09 1.2 6.2E-09Benzo(k)fluoranthene 3.22E-01 1 2.0E-08 NA NA 3.2E-09 1.2 3.8E-09Cobalt 5.70E+01 1 3.5E-06 0.02 1.8E-04 5.6E-07 NC NADibenz(a,h)anthracene 1.78E-01 1 1.1E-08 NA NA 1.7E-09 4.1 7.1E-09Indeno(1,2,3-cd)pyrene 5.94E-01 1 3.7E-08 NA NA 5.8E-09 1.2 7.0E-09Nickel 9.94E+02 1 6.2E-05 0.02 3.1E-03 9.7E-06 NC NA

3E-03 1E-07




NA = Not Applicable



DERMAL CONTACT WITH SOIL: ADOLESCENT STUDENT



(ABSds)


Dermal Chronic


Hazard Quotient

Lifetime Average

Daily Dose (LADD)


Excess Cancer Risk

(mg/kg) (--) (mg/kg-d) (mg/kg-d) (--) (mg/kg-d) (mg/kg-d)-1 (--)Benzo(a)anthracene 3.37E-01 0.15 2.7E-08 NA NA 4.3E-09 1.2 5.1E-09Benzo(a)pyrene 6.27E-01 0.15 5.0E-08 NA NA 7.9E-09 12 9.5E-08Benzo(b)fluoranthene 5.32E-01 0.15 4.3E-08 NA NA 6.7E-09 1.2 8.1E-09Benzo(k)fluoranthene 3.22E-01 0.15 2.6E-08 NA NA 4.1E-09 1.2 4.9E-09Cobalt 5.70E+01 0.01 3.1E-07 0.02 1.5E-05 4.8E-08 NC NADibenz(a,h)anthracene 1.78E-01 0.15 1.4E-08 NA NA 2.2E-09 4.1 9.2E-09Indeno(1,2,3-cd)pyrene 5.94E-01 0.15 4.8E-08 NA NA 7.5E-09 1.2 9.0E-09Nickel 9.94E+02 0.01 5.3E-06 0.02 2.7E-04 8.4E-07 NC NA

3E-04 1E-07






NA = Not Applicable



INHALATION OF RESUSPENDED PARTICULATES FROM SOIL: ADOLESCENT STUDENT




Annual Average

Daily Dose (AADD)

Inhalation Chronic


Hazard Quotient



(SFi)

Excess Cancer Risk


7E-04 9E-09




NA = Not Applicable



SUMMARY RISK CHARACTERIZATION: ADOLESCENT STUDENT

ChemicalIncidental

Ingestion of Soil


Inhalation of Particulates

Excess Cancer Risk

Benzo(a)anthracene 4.0E-09 5.1E-09 1.3E-12 9.1E-09Benzo(a)pyrene 7.4E-08 9.5E-08 2.5E-11 1.7E-07Benzo(b)fluoranthene 6.2E-09 8.1E-09 2.1E-12 1.4E-08Benzo(k)fluoranthene 3.8E-09 4.9E-09 1.3E-12 8.7E-09Cobalt NA NA NA NADibenz(a,h)anthracene 7.1E-09 9.2E-09 7.5E-12 1.6E-08Indeno(1,2,3-cd)pyrene 7.0E-09 9.0E-09 2.4E-12 1.6E-08Nickel NA NA 9.3E-09 NATotal 1.0E-07 1.3E-07 9.3E-09 2.3E-07NA = Not Applicable



SUMMARY RISK CHARACTERIZATION: ADOLESCENT STUDENT

ChemicalIncidental

Ingestion of Soil



Benzo(a)anthracene NA NA NA NABenzo(a)pyrene NA NA NA NABenzo(b)fluoranthene NA NA NA NABenzo(k)fluoranthene NA NA NA NACobalt 1.8E-04 1.5E-05 6.5E-04 1.9E-04Dibenz(a,h)anthracene NA NA NA NAIndeno(1,2,3-cd)pyrene NA NA NA NANickel 3.1E-03 2.7E-04 3.2E-06 3.4E-03Total 3.3E-03 2.8E-04 6.6E-04 3.6E-03NA = Not Applicable


Results of Soil Sampling Investigation and Health Risk...

Documents

Transcript of Results of Soil Sampling Investigation and Health Risk...