EPA/ROD/R01-97/102
                                    1997
EPA Superfund
     Record of Decision:
     DAVIS (GSR) LANDFILL
     EPA ID:  RID980731459
     OU01
     GLOCESTER, RI
     09/29/1997

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                                  DECLARATION FOR THE RECORD OF DECISION

SITE NAME AND LOCATION

Davis Glocester-Smithfield Regional  (GSR) Landfill
Glocester/Smithfield, Rhode Island

STATEMENT OF PURPOSE

This decision document presents the selected No Action decision for the Davis GSR Landfill Site  (the
"Site"), located in Glocester and Smithfield,,  Rhode Island.  This document was developed in accordance
with the Comprehensive Environmental Response,  Compensation and Liability Act of 1980  (CERCLA) ,  as
amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA),  and to the extent
practicable, the National Contingency Plan  (NCP); 40 CFR Part 300 et seq. (1990). The Region I Director
of the Office of Site Remediation and Restoration has been delegated the authority to approve this Record
of Decision.  The State of Rhode Island has concurred with the No Action decision.

STATEMENT OF BASIS

This decision is based on the administrative record compiled for the Site which was developed in
accordance with Section 113(k) of CERCLA.  The administrative record is available for public review at
the E. Smithfield Public Library in Esmond, Rhode Island, and at the EPA Region I Office of Site
Remediation and Restoration Record Center in Boston Massachusetts. The administrative record index
(attached as Appendix A to the ROD) identifies each of the items which comprise the administrative record
upon which the selection of the remedial action is based.

DESCRIPTION OF THE SELECTED REMEDY

EPA has determined that No Action is necessary to address the contamination at the Site. The Site poses
no unacceptable current or potential threat to human health or the environment. Groundwater monitoring
will be conducted for a period of at least five years to verify that no unacceptable exposures to
potential hazards posed by conditions at the Site occur in the future.

DECLARATION

EPA has determined that its response at this site is complete.  Therefore, the site now qualifies for
inclusion on the Construction Completion List.

As this is a decision for No Action, the statutory requirements of CERCLA Section 121 for remedial
actions are not applicable and no statutory five year review will be undertaken.



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                                      REGION I
                             RECORD OF DECISION SUMMARY


                                   SEPTEMBER 1997

                              RECORD OF DECISION SUMMARY
                                  DAVIS GSR LANDFILL

                                  TABLE OF CONTENTS


Contents                                                                         Page  Number


I.  SITE NAME, LOCATION AND DESCRIPTION	1
       A.   General Description  	  1
       B.   Geology and Hydrogeology	1

II. SITE HISTORY AND ENFORCEMENT ACTIVITIES 	  2
       A.   Land Use and Response History	2
       B.   Enforcement History  	  5

III. COMMUNITY PARTICIPATION	5

IV.  SCOPE AND ROLE OF NO ACTION REMEDY	6

V.  SUMMARY OF SITE CHARACTERISTICS 	  6
      A.  Landfill Source and Soil	6
      B.  Ground Water	9
      C.  Surface Water and Sediment	12
      D.  Air	14

VI. SUMMARY OF SITE RISKS	14
      A.  Human Health Risk Assessment	14
      B.  Ecological Risk Assessment	50

VII. DESCRIPTION OF NO ACTION ALTERNATIVE	52

VIII. DOCUMENTATION OF SIGNIFICANT CHANGES	52

IX. STATE ROLE	52

    APPENDIX

      A. ADMINISTRATIVE RECORD INDEX

      B. FIGURES AND TABLES

      C. RIDEM DECLARATION OF CONCURRENCE

      D. RESPONSIVENESS SUMMARY

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RECORD OF DECISION SUMMARY
Davis GSR Site

I.  SITE NAME, LOCATION AND DESCRIPTION

     A.   General Description

The Davis Glocester-Smithfield Regional  (GSR) landfill site  (the Site) is approximately 58 acres
in size, and the main landfill portion is about 18 acres.  The landfill is located at Latitude N41-55"
and Longitude W71-35" off Tarkiln Road in the towns of Smithfield and Glocester, Rhode Island (Figure 1).
The Site consists mainly of wooded and wetland areas with the landfill being situated on a local high
area underlain by glacial deposits and extending into an area created by the partial landfilling of a
small valley.  The land surrounding the Site is considered semi-rural. Within 1 mile of the Site, the
land is predominately wooded with wetlands and cleared areas. Developed land is limited and is dominated
by low-density residential use.  These residents obtain their water from private wells.  The future use
of the Site and surrounding land is not expected to change.

The GSR Landfill accepted municipal and commercial wastes from the Boston and Providence areas from 1974
to 1982.  The 18-acre main landfill denoted as Landfill Area A, is estimated to be approximately 37-44
feet deep.  Monitoring well logs indicate that the contents of the landfill consist mainly of municipal
solid waste, including trash, refuse, plastic, paper, wood, glass, bricks, sludge, fiber board,  and
medical waste.  A 3-acre area in the wetlands immediately south of the main landfill contain 10 to 18
feet of trash and is denoted as Landfill Area B.  The Site is bordered on the south, east, and west by
wetlands, and on the north by wooded rural residential areas.  On the east side of the landfill is Nine
Foot Brook, which flows south into Waterman Reservoir approximately 2.5 miles downstream.  On the west
side is an unnamed stream, which flows southwesterly into wetlands that eventually discharge into Nine
Foot Brook south of the Site (Figure 2).

     B.   Geology and Hydrogeology

The region where the Site is located is underlined by granite and granite gneiss bedrock which transmit
water through openings that occur primarily as a result of weathering near the surface and joints that
extend to greater depths.  Bedrock varies in depth throughout the Site; the greatest depth to bedrock
encountered during the drilling program was 64 feet below grade, at the south side of the landfill.
Bedrock is exposed on the western side of the landfill where the relief steeply rises.  In areas beneath
or along the periphery of the landfill where bedrock is shallow or at the surface, refuse material may be
in direct contact or within a few feet of bedrock, possibly resulting in leachate directly affecting
bedrock groundwater.  Over the bedrock, the Davis GSR Landfill is underlain primarily by glacial till,
consisting of sorted sand and gravel with minor amounts of silts and clay (Figures 3-8).

Measurements of groundwater levels indicate an upward gradient of groundwater flow to the north and east
of the landfill as well as in the wetlands south of the unnamed stream.  A downward gradient was observed
at the Landfill Area B and to the immediate west of Landfill Area A.  In general, groundwater recharge
occurs in the highland areas and groundwater discharge occurs in low land areas where the streams and
wetland are located.  Based on the information collected from the site monitoring wells,  groundwater in
bedrock flows from west to east toward the landfill.  Underneath the landfill, the hydraulic gradient in
the bedrock flattens, and flow in the bedrock becomes radial flowing to the east, northeast, and
southeast.  This radial flow apparently occurs because there is recharge to bedrock from the overburden
underneath the landfill.  The streams on-site do not appear to significantly affect groundwater flow in
bedrock in the immediate area of the landfill because groundwater in the bedrock is semi-confined from
overburden deposits  (Figure 9).  Beneath the landfill, overburden groundwater flows radially in all
directions except northwest, which is upgradient.  The radial flow is induced due to recharge through the
fill creating a groundwater mound.  In the overburden aguifer, flow primarily discharges into surface
water and wetland areas  (Figure 10).

The dominant surface water bodies at the Site are Nine Foot Brook, which originates off-site to the
northeast, and the unnamed stream, which originates just northwest of the landfill and flows through
wetlands downgradient until it converges with Nine Foot Brook.  From the confluence, Nine Foot Brook
flows south towards the Waterman Reservoir.  These streams are located in topographic lows and receive
some groundwater discharge from the underlying aguifer.

A more complete description of the Site can be found in the Remedial Investigation report on Davis GSR
Landfill located in the Administrative Record.

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II.   SITE HISTORY AND ENFORCEMENT ACTIVITIES

     A.   Land Use and Response History

The land surrounding the Davis GSR Landfill is considered semi-rural.  Limited developed land within one
mile of the Site is dominated by low density residential uses, with remaining areas being predominantly
wooded with various wetlands and cleared areas.  A few residents within 1-mile of the Site have used for
livestock grazing.  These small "recreational" farms have limited numbers of cows, goats, and others
animals for non-commercial use.  Tarkiln Road, Evans Road, Eddy Road, and small portions of Mann School
Road, Burlingame Road, and Farnum Road lie within a 1-mile radius of the Davis GSR Landfill.
Approximately 50 houses are located within a 1-mile radius of the landfill,  all of which draw water from
private wells.  The majority of the residential wells in the area are drilled into the bedrock, while a
few are shallow hand dug wells. Thus, drinking water is derived from both overburden and bedrock
aguifers.

The Davis Liguid Chemical Disposal Superfund Site and the adjacent large tire pile is located
approximately 2,500 feet east of the Davis GSR Landfill.  EPA and the State are currently involved in
site characterization activities at that Superfund Site and in drummed waste and tire removal activities.

Waterman Reservoir is located approximately 2.5 miles downstream of the Davis GSR Landfill and is fed by
the Nine Foot Brook.  The reservoir is a 263 acre body of water classified by the State as a Class B
water body, meaning it may potentially serve as a public water supply with appropriate treatment.

There are different zoning designations for the Davis GSR Landfill and surrounding land within a 1-mile
radius, depending on the town where the land lies.  According to the Town's Zoning Maps, the majority of
the Site land in Smithfield is classified as residential conservation or R-200, which reguires a 200,000
sguare foot minimum lot size.  A small portion of land southeast of Burlingame Road is classified low
density residential or R-80, which reguires an 80,000 sguare foot minimum lot size.  The land located in
the town of Glocester, where the major portion of the Site is located, is categorized as an agricultural
residential zone or A-4 which reguires a minimum lot size of 4 acres.

The Davis GSR Landfill was first licensed by the state to receive solid waste in 1974, and acceptance of
waste ceased in 1982.  In the 1970s and early 1980s, the public expressed concern about Mr. Davis'
operation of the landfill and the landfill's effect on the local groundwater drinking supply.  In
February 1976, the Rhode Island Department of Health (RIDOH), the predecessor of the Rhode Island
Department of Environmental Management (RIDEM) as the licensing and regulatory agency for solid waste
management facilities, ordered Mr. Davis the property owner, to undertake extensive activities in the
south wetlands where solid waste was improperly disposed.  This mandated activity included construction
of trenches, installation of culverts, and excavation and removal of refuse material from the wetland
area.  In September 1977, RIDOH ordered Mr. Davis to provide plans and a timetable to close the portion
of the landfill located in the south wetlands..

In January 1978, RIDEM denied a reguest by Mr. Davis to renew his solid waste disposal license citing
numerous operating violations under "Rules and Regulations for Operating Solid Waste Management
Facilities" and failure to comply with previous orders issued by RIDOH in 1976 and 1977.  At the reguest
of Mr. Davis a hearing on this denial was held on September 20, 1978. Testimony during this hearing
detailed the finding of several inspections conducted by the State in 1978,  which showed that Mr. Davis
failed to meet the reguirements of regulations regarding items such as lift height, daily cover, surface
water separation, brush handling, number of bulldozers, fire extinguishers on eguipment, intermediate
cover, final cover, and bulky waste separation.  Mr. Davis appealed this decision and in April 1982,
after a number of decisions by the Rhode Island Courts, Rhode Island Supreme Court ruled in favor of
RIDEM.  Immediately following the court ruling, on April 14, 1982, RIDEM notified Mr. Davis that he was
allowed three weeks after the effective date of the original closure decision to submit the reguired
engineering plans for the final closure of the landfill.  At that time the landfill had stopped accepting
solid waste, but no closure plans have been filed to this date.  A final cover complying with state
regulations has not been applied.  The existing cover material currently consists of sand and silty sand,
and is overgrown with naturally occurring grasses and trees.

In 1985, the Town of Glocester took over the property for non-payment of taxes.  On August 19, 1988, the
Town canceled all delinguent taxes relating to the property and transferred the property back to Mr.
Davis, who remains the current owner of the Site.

Sampling of on-site wells conducted by RIDEM between 1980 and 1982 indicated presence of inorganic and
organic groundwater contamination underneath the landfill.  Compounds detected included toluene
1,1-dichloroethane, chloroform, methyl ethyl ketone, 1,1,1-trichloroethane,  and benzene.  In May 1982,
Ecology and the Environment, Inc., a Field Investigation Team  (FIT)  contractor for EPA, completed a

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Preliminary Assessment  (PA) at the Site which included a recommendation that EPA conduct a Site
Inspection  (SI) at the Site.  The planned November, 1983 SI was impeded by Mr. Davis' refusal to grant
permission for access to the property.  In June, 1984, NUS Corporation, another FIT contractor, collected
a total of 16 samples from nearby six residential wells, three surface water locations, and two soil
locations.  EPA found no Volatile Organic Compounds (VOCs) in any of the samples.  A residential well
located on Tarkiln Road was tested by RIDEM in June 1984 and June 1985 and had detected 1,1-
dichloroethane contamination of 10 micrograms per liter  (ug/1).  In October, 1984, NUS collected
additional 13 samples, including samples of surface water, soil and residential wells, which were
analyzed for VOCs and metals.  These samples were collected in the area immediately surrounding the
landfill due to the denial of access by the owner.  No VOCs were found in the residential wells.

The SI report prepared in October 1985, which incorporated data from EPA and RIDEM's sampling activities
conducted to that date, recommended that further investigations should be performed such as sampling
on-site monitoring wells, conducting hydrogeological investigation of the area, and installation of
additional monitoring wells downgradient from the landfill.  The National Priorities List  (NPL) Update
#3, April 10, 1985, proposed that the Davis GSR Landfill be added to the NPL.  On June 10, 1986, EPA
added the Davis GSR Landfill site after no comments were received during the public comment period.

RIDOH and EPA also have periodically sampled residential wells in the vicinity of the Site since the
early 1980s.  In February and November 1988, EPA analyzed samples from 15 residential wells for VOCs and
metals.  No elevated concentrations were detected.  The latest sampling by RIDOH was done in 1992 and
1994 for a total of 20 wells.  None of the wells confirmed the presence of VOCs.  From 1991 to 1993,
after site access has been finally obtained, COM Federal Programs Corporation, a contractor to EPA,
conducted an extensive remedial investigation to determine the extent and nature of contamination at the
Site.  Results of this investigation concluded that the landfill appears to be a source of numerous
chemicals with off-landfill migration confined to the immediate vicinity of the landfill as there is no
evidence of contamination downgradient.  No distinct plume of groundwater contamination was found to be
emanating from the landfill.

     B.   Enforcement History

Based on investigations conducted by EPA, in 1990 EPA issued 83 104(e) letters to persons believed to
have information regarding the Site, including potential generators and transporters.  In 1992, EPA
issued 62 additional 104(e) letters to candidate potentially responsible parties based upon the
information provided from the 1990 104(e) responses, additional interviews, available records and
title/deed documentation.  In addition, EPA issued selective non-compliance letters in 1991 and 1993.

After investigation of numerous sources of information related to waste transported and disposed of at
the Site, EPA has not named any potentially responsible parties at this Site.

III.   COMMUNITY PARTICIPATION

In the 1970s and 1980s, during the years of the landfill operation, community concern with the activities
at the landfill has been moderate to high.  In the recent Site history, however, community concern and
involvement has been low.  In the 1992, a community group "Dump the Dump" was awarded the Technical
Assistance Grant (TAG) for both Davis Liguid and Davis GSR Superfund Sites, but no activities or
expenditure of funds by the group have occurred to date.  EPA has kept the community and other interested
parties apprised of the Site activities through informational meetings, fact sheets, press releases and
public meetings.

On June 18, 1997, EPA made the draft administrative record available for public review a EPA's offices in
Boston and at the E. Smithfield Public Library at 50 Esmond Street, Smithfield, Rhode Island.  EPA
published a notice and brief analysis of the Proposed Plan in the Woonsocket Call on June 11, 1997, and
made the Plan available to the public at the E. Smithfield Public Library.  EPA also mailed copies of the
Press Release and the Proposed Plan to the members of the public on the Davis GSR Landfill mailing list
on June 16, 1997.

On June 23, 1997, EPA held an information session and public meeting to discuss the results of the
Remedial Investigation and to present the Agency's Proposed Plan.  Also during this meeting, the Agency
answered guestions on the Proposed Plan from the public.  From June 24 through August 22, 1997, the
Agency held a 30-day public comment period to accept public comment on the proposal presented in the
Proposed Plan and on any other documents previously released to the public.  On July 15, 1997, the Agency
held a public hearing and accepted oral comments on the Proposed Plan.  The comments and the Agency's
response to comments are included in the Responsiveness Summary in Appendix D.  A transcript of this
hearing is attached as part of Appendix D.

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IV.   SCOPE AND ROIiE OF NO ACTION REMEDY

This Record of Decision reflects EPA's determination that no further CERCLA action is required at the
Davis GSR Landfill Site.  The baseline risk assessment concluded that conditions at the Site pose no
unacceptable risk to human health and the environment.  Based on the levels of organics and metals that
were detected in the soils, sediments, surface water, groundwater, and air and the unlikely future
exposure to the groundwater in a limited area in the wetlands immediately adjacent to the landfill, EPA
has determined that the potential for adverse ecological and human health risks from site groundwater and
other media to be unlikely.  Limited monitoring of groundwater, including residential well monitoring,
will be conducted for a period of at least five years.  The scope and frequency of the monitoring will be
adjusted as necessary, based on the sampling results.

The decision by EPA not to pursue further action at the Site is not a determination that no action is
warranted under other regulations and statutes.  EPA has determined that the CERCLA cleanup authority is
not the appropriate mechanism to handle the closure of this municipal waste landfill. The State's
authority under their laws and regulations is in no way limited by EPA's No Action decision.

EPA has the authority to revisit the No Action decision even if the Site is removed from the NPL. This
could occur if future conditions indicate that an unacceptable risk to human health or the environment
would result from the exposure to contaminants at the Site.

V.   SUMMARY OF SITE CHARACTERISTICS

The significant findings of the Remedial Investigation are summarized below.  To maintain consistency
with the Remedial Investigation Report, the levels of organic contaminants are reported in parts per
billion (ppb),  while levels of metals in aqueous media are reported in ppb and in soils are reported in
parts per million (ppm).

     A.   Landfill Source and Soil

The Davis GSR Landfill was apparently constructed on a small hill, almost completely surrounded by
wetlands.   Portions of the hill were displaced to make room for refuse, which was also deposited in the
perimeter wetlands south of the main landfill.  A large portion of the landfill area was built on sand
and gravel overburden, with the perimeter area of the filled wetlands on peat.  The landfill does not
have a bottom liner, leachate collection system, or an engineered cover.  The side slopes are very steep
in many locations.  Intermittent leachate seeps emanate from the side slopes onto surface soil; this flow
along with runoff from the landfill migrates into nearby surface water and sediments.  The thickness of
the existing cover material ranges from 0 to 18 inches and consists of fine to medium grained sand with
traces of gravel and organic soils.  Vegetative cover at the landfill varies widely across the site, with
heavy underbrush, trees, and grasses established over the majority of the surface area.  Steep slopes
have been covered with large boulders/rip rap.  Erosion does not appear to be a major concern at this
landfill.

Waste depositions limits were established from surficial indicators and test borings conducted during the
well installation program.  The main landfill  (Landfill Area A) is approximately 18 acres with depth
ranging from 44 feet in the southern portion to 37 feet in northern portion.  The volume of the landfill
above the fill-native ground interface was estimated at 700,000 cubic yards (cy).  Logs from the
monitoring wells installed in July 1992 showed encounters with municipal solid waste and soil layers;
some solid waste was also evident on top of the northern portion of the landfill as well as along some
steeper slopes.  Based on aerial photos and field observations, on-site borrow used for intermediate
landfill cover appears to have been mined from the area immediately northwest of the landfill.  Apparent
settlement at a differential rate resulted in settlement cracks and areas of depression observed on top
of the northern and southern portions of the landfill.

In Landfill Area B soil fill material and trash were observed from the ground surface to a depth of 10 to
18 feet below ground surface.  Below fill soils, on the average, trash was observed from a depth of 8
feet to a depth of 16 feet.  Based on the defined limits, Landfill Area B is a about 3 acres with total
volume estimated at 70,000 cy.  In addition, miscellaneous forms of solid waste, such as tires, bales of
wires, and various scrap metal have been placed around the landfill.

To identify source contamination, two rounds of leachate sampling was conducted and a leachate production
model was used to perform a water balance analysis.  A total of nine leachate locations was identified by
visible staining at the seeps.  Eight locations were identified as non-aqueous  (stained soil), and one
location was an aqueous seep.  Three volatile organic compounds in four soil leachate samples were
detected at levels below 100 ppb.  Phthalates and PAHs were more prevalent, with the diethyphthalate
found at the highest concentration of 750 ppb.  Low levels of pesticides and PCBs were also detected in

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several locations.  The metals detected in all leachate soil samples were aluminum, barium, calcium,
iron, magnesium, manganese, and vanadium.  High concentrations of iron were consistent with the
rust-colored staining observed at the leachate seeps..  Arsenic, cobalt, copper, lead, nickel, potassium,
and zinc were detected freguently, while mercury was only detected once.  Location along western slope of
the landfill tended to exhibit the highest metal concentrations.  The only aqueous leachate sample
located on the eastern slope of the landfill had few organic compounds found at minimal levels in the low
ppb range.  The concentrations of many metals, including iron, manganese, lead, nickel, and zinc at that
location were elevated compared to concentrations that would be expected to occur naturally in
groundwater.  A fairly random distribution of compounds in the leachate indicates that these chemical
concentrations are due to a variety of different sources from within the landfill.

Leachate discharge rates were evaluated using the HELP model which generates a water balance based on the
expected precipitation condition and the landfill characteristics.  Mass loading of contaminants from the
landfill source area to the groundwater beneath the landfill is expected to be highly variable and is
likely to continue at present although waste disposal was stopped in 1982. Due to inherent variability of
factors controlling leachate generation, it is not possible to accurately estimate the length of time
over which the landfill will continue as a source of contamination.

Ten source area soil borings were performed to evaluate the subsurface soil quality (Figure 11).  A total
of 14 volatile compounds were detected in samples taken from Landfill Area A, with most detections found
on the northwestern perimeter of the landfill.  The highest concentrations were toluene (120 ppb),
chlorobenzene (160 ppb), ethylbenzene (440 ppb), and total xylenes (440 ppb). These maximum
concentrations were found at two locations from depths of 8 to 10 feet and 24.5 to 26.5 feet.  Landfill
Area B included detections of 11 organic compounds, with highest concentrations detected at depths from 8
to 12 feet.  The highest concentrations detected were toluene  (2,000 ppb), chlorobenzene (450 ppb),
ethylbenzene (450 ppb), and total xylenes (700 ppb).  Similarly, 28 and 14 semivolatile compounds, mostly
PAHs, phenols and phthalates, were detected in Landfill Area A and Landfill Area B, respectively.
Highest concentrations included total PAHs at 1,050, 100 ppb and phenols of 10,000 ppb at the Landfill
Area A, and phthalates at 9,000 ppb at Landfill Area B. A few elevated levels of PCBs and pesticides were
detected sporadically in the source area. Concentrations of inorganics in excess of those typically found
in regional soils include arsenic, calcium,  chromium, copper, iron, lead and zinc.  Heavy metals, found
primarily in Source Area A, include mercury, nickel, and silver.  The contaminant distribution appears to
be typical of the random pattern normally associated with landfills.

Off-landfill soil quality was evaluated at 14 soil boring locations,  including soil borings along the
unnamed stream,  Nine Foot Brook, and two background locations north of the Site.  Four volatile organic
compounds at concentrations below 100 ppb, and one semivolatile compound, benzo(a)pyrene,  at 1,700 ppb
were detected at a depth of 4-6 feet at the confluence of the unnamed stream and Nine Foot Brook Toluene
was detected at less than 5 ppb at three locations near the Nine Foot Brook  Acetone was also detected at
four locations along the Brook, as well as in the background samples.  Bis(2-ethylhexyl) phthalate was
detected northeast of the landfill at the concentrations similar to the levels found in the background.
No pesticides or PCBs were detected in any soil sample at these locations.  Three metal concentrations
near the unnamed stream exceeded the regional levels:  beryllium  (2.4 ppm),  calcium (11,500 ppm), and
selenium  (12.5 ppm) at 4-6 feet depth.  Analytes that exceeded site-specific background in these
locations include barium, beryllium, cobalt, nickel, selenium, and vanadium.  Soil borings east of the
landfill, along Nine Foot Brook, contained the greatest number of inorganics exceeding background levels.
Two inorganic compounds exceeded regional levels:  antimony  (5.4 ppm) and zinc  (56.1 ppm)  were found near
the unnamed stream.  Similar to locations at the unnamed stream, a number of metals exceeded the
background concentrations as well.

A total of 16 surficial soil samples were collected on an immediately adjacent to the landfill. Surficial
soils contained virtually no VOCs and a few semivolatiles scattered throughout the landfill and
surrounding area.  Overall, three VOCs,  eight different PAHs and four phthalates were detected at several
locations, at levels generally below 100 ppb.  Several pesticides were also detected,  primarily along the
easterly perimeter of the landfill, with the highest detection of 4,4'-DDE at 10 ppb.   PCBs were detected
at five locations, with the highest found level of Aroclor-1260 at 310 ppb just northeast of the
landfill.  Several inorganic constituents were found to exceed background concentrations.   Mercury and
silver were prevalent throughout the Site and copper and zinc were found in select locations. On the
other hand, beryllium and lead levels exceeded these found regionally,  while non-background samples of
these compounds were below the mean regional values.  Three additional compounds, calcium,  iron and
manganese were found to exceed the background and regional criteria.

To further characterize the source contamination, the landfill soil gas survey conducted over Landfill
Area A at 83 grid points spaced on a 100 feet grid measured selected VOCs present below the landfill
surface.  Over 97 percent of the landfill surface had levels below 50 ppm, with 62 percent of the area
having levels below 10 ppm of total volatile organics.  One area, approximately 3,800 sq.  ft or 0.5
percent in size, had levels greater than 100 ppm.

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     B.   Ground Water

The geologic investigation included bedrock formation mapping, subsurface drilling, bedrock coring, and a
geophysical survey.  Hydrogeologic investigation performed at the Site included synoptic water level
measurements, slug tests at monitoring wells, and sieve test  (grain size) analysis on soil samples.

During the course of the remedial investigation, 32 monitoring wells were installed in a vicinity of the
Davis GSR Landfill to monitor groundwater guality and the flow system  (Figure 11). Monitoring wells were
screened in bedrock and across various depths in the overburben. Groundwater elevations in the
surrounding wetlands are at the ground surface or, in dry weather, slightly below the surface.  The
estimated groundwater elevation in the landfill is approximately 20 feet above the water table elevation
in the surrounding wetlands.  Synoptic water level elevations recorded in wells located on the landfill
depict a groundwater mound that, subject to hydrological variances, has been recorded as much as 40 feet
above the water table in the surrounding wetlands. Fractures  (faults and joints) were observed on bedrock
outcrops to the south and east.  Bedrock outcrops were observed in close proximity to refuse in both
Landfill Area A and B, indicating there may be some locations where refuse is in contact with or close
proximity to bedrock.  As would be expected in a wetland with a peat substrate, the hydraulic
conductivity at the Site is lowest in Landfill Area B.  The groundwater gradient appears to be downward
in Landfill Areas A and B, while and upward gradient exists along the unnamed stream, Nine Foot Brook,
and wetlands to the south of the landfill.

Three rounds of groundwater sampling for organic and inorganic parameters were conducted in 1992 and
1993.  The discussion of the results focuses of Rounds 2 and 3 since all wells at the site were sampled
during these rounds using the low-flow purge and sample method.  Five overburden monitoring wells were
installed to evaluate source groundwater  (groundwater under the landfill area, where fill is present).
During the three rounds of sampling, between 26 and 45 various organic compounds were detected in the
source groundwater wells.  The most common volatile compounds detected were BTEX compounds (benzene,
toluene, ethylbenzene, and xylenes).  The semivolatile compounds detected included PAHs, phenolic
compounds, and phthalates.  No PCBs were detected in any wells, and pesticides were only found at low
concentrations at the Landfill Area B.  Most of the individual organic compounds were detected at
concentrations below 100 ppb.  Organic compounds detected over 100 ppb included acetone (188 ppb),
cis-1,2-dichloroethene (115 ppb), xylenes (120 ppb), naphthalene  (680 ppb), 4-methylphenol (110 ppb), and
phenol  (220 ppb).  Two source bedrock wells were also installed and sampled in Rounds 2 and 3.  As in the
source overburden wells,  several BTEX and semivolatile compounds were detected.  There were no individual
compounds detected above 100 ppb in these bedrock wells.  The highest concentration detected in source
bedrock samples was 39 ppb of ethylbenzene in the north portion of the Landfill Area A.  There were no
pesticides or PCBs found in source bedrock samples.

Inorganic contaminants were analyzed for both filtered and unfiltered samples.  In the overburden and
bedrock wells, calcium, iron, magnesium, manganese, potassium, and sodium were detected at the highest
concentrations.  The concentrations of these metals were elevated with respect to the site-specific
background concentrations but were consistent with municipal landfill leachate.  Other metals, which were
detected above background levels or were not detected in the background, include aluminum, antimony,
arsenic, barium, cadmium, chromium, cobalt,  copper, lead, mercury, nickel, silver, vanadium,  and zinc.
In general, the maximum concentration detected in source bedrock was less than the maximum concentration
detected in source overburden.

In addition to monitoring wells installed in the landfill, overburden and bedrock wells were installed
immediately adjacent to and further down gradient from the landfill.  Six wells (MW104A, MW108A/D,
MW112D, and MW114A/D) were installed on-site along the eastern periphery of the landfill near Nine Foot
Brook, ten wells (MW115A/B/D, MW117A, MW118A/B/D, and  MW119A/B/D) were installed further to the east and
south, beyond the wetlands surrounding the Site, one additional well (MW110D) was installed to the west,
beyond the unnamed stream, and wells 120A/D and 121A/D were considered background wells.

No volatile or semivolatile organic compounds were detected in wells associated with the unnamed stream
(MW110D, MW115A/B/D, and MW117).  During Round 2, in the area associated with discharges into Nine Foot
Brook  (MW104A, MW108A/D,  MW114A/D, MW118A/B/D, and MW119A/B/D) organics that were detected include low
levels of volatiles and semivolatiles (less than 10 ppb, some below ppb), which were detected in MW104,
and MW119A (overburden) and MW108D and MW112D (bedrock).  The highest organic detection, acetone at 220
ppb, occurred at MW108A.   One slight exceedance of a regulatory criterion  (federal Maximum Contaminant
Level  (MCL)=5 ppb)  occurred for benzene at MW114A, with a concentration of 6.1 ppb.  This location, in
the wetland area between the landfill toe and Nine Foot Brook, had the greatest number of detected
organic compounds in Round 2  (six volatile,  three semivolatile, and one pesticide).  Two PAHs were
detected at MW112D and MW114D, at concentrations below 10 ppb.

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During Round 3, volatile organics were detected at low concentrations  (less than 10 ppb) in Nine Foot
Brook wells MW104, MW108A, and MW119D.  Volatile and semivolatile organics were detected at higher
concentrations  (up to 160 ppb) at MW112D, MW108D, MW114A, and MW114D. Again, the only MCL that was slight
exceeded was for benzene, which was exceeded in wells  (MW112D, MW108D, MW114A, and MW114D) located
between the landfill and landfill and Nine Foot Brook, with the maximum concentration of 8.9 ppb.  No
PCBs were detected in any of the wells.  VOCs in groundwater were detected only in samples from wells
located along the eastern periphery of the landfill, indicating that minimal migration have occurred.

In both bedrock and overburden samples site-specific background concentrations were exceeded for up to 12
metals.  None of the detected inorganics exceeded MCLs, although aluminum and iron concentrations were
higher than secondary MCLs at several wells.  Secondary MCLs, based on aesthetic water guality, are set
at concentrations that when exceeded do not cause human health concerns but sometimes cause water to have
an unappealing appearance or taste.  The Maximum Contaminant Level Goal (MCLG) for manganese was exceeded
in several bedrock and overburden wells closest to the landfill.  MCLG is a non-enforceable concentration
of a drinking water contaminant that is protective of adverse human health affects and allows an adequate
margin of safety.  Locations exceeding background most frequently were MW108, MW112 and MW114, all
located along the eastern toe of the landfill.

In addition to the contaminant data, conventional water quality parameters such as biological oxygen
demand (BOD) ,  total hardness, chemical oxygen demand  (COD) ,  total phosphorus, total organic carbon (TOG),
total kjeldahl nitrogen  (TKN), Chloride, bicarbonate, sulfate, total dissolved solids (TDS),  and total
suspended solids  (TSS) were measured.  At wells that discharge into the unnamed stream,  the conventional
parameters are similar in concentration to background wells.  However, at wells which discharge into Nine
Foot Brook, the conventional parameters exceed the background levels for almost every analysis,
indicating that this would be the major vector for movement of the contaminants from the landfill.

The dominant fate and transport mechanism for the volatiles in groundwater at the Davis GSR Landfill are
sorption, the partitioning of a compound from groundwater to aquifer solids, and biodegradation.
Inorganics in groundwater are likely controlled by sorption and precipitation processes.  Statistical
analysis on the groundwater data yield no correlation between contaminants, indicating randomness in
distribution between contaminants at the same location.  However, three concentric circular clusters of
sample locations were identified:  a contaminant source inside Landfill Areas A and B; and area along
perimeter of the landfill, including wells between the landfill and Nine Foot Brook, and wells in the
background and wetlands located further downgradient from the landfill.  This analysis show lesser
contaminant influence in the groundwater surrounding the landfill and no defined contaminant plume
leaving the site.

     C.   Surface Water and Sediment

In the Spring and Fall of 1992, two phases of surface water sampling were performed at Davis GSR Landfill
along the Nine Foot Brook, the unnamed stream, in the wetland downstream from the site,  and at the
background locations  (Figure 12).  Each sample was analyzed for volatiles, semivolatiles, pesticides,
PCBs, and inorganics.  Volatile organics were infrequently detected in the surface water samples, with no
detected values in the Phase 1.  Two samples had detects for a total of four VOCs, all below 10 ppb.   One
of these locations (adjacent to the unnamed stream) and location downgradient of the landfill on Nine
Foot Brook, also had the only SVOC detected, 4-methylphenol, at 1 ppb and 3 ppb, respectively.  No PCBs
were found in any sample, and the only pesticide detected was 4,4'-DDT, at 0.1 ppb.

A number of inorganic compounds exceeded either federal or Rhode Island ambient water quality criteria
(AWQC) in background and site surface waters.  AWQC, which include values for both acute and chronic
effects,  were developed under the Clean Water Act Section 304 for protection of aquatic life.  Iron and
lead were found to be prevalent throughout the site; however AWQC was exceeded in both background and
site surface waters.   Similarly, aluminum exceeded AWQC in background and in 14 of the 17 locations
tested.  Zinc exceeded AWQC in one location downgradient of the landfill.   Other metals exceeding AWQCs,
mostly at a single location, include beryllium, copper, mercury, silver, and thallium.  Compound found to
be prevalent and frequently exceeding background include barium, calcium,  iron, magnesium, manganese,
potassium and sodium.  The downstream sampling location SW014, prior to the confluence of the Nine Foot
Brook and the unnamed stream, exhibited the most exceedances of AWQCs.  This location, along with SW012
(immediately upstream) also exhibited the only background exceedances of seven inorganics:  aluminum,
barium, copper, mercury, nickel, zinc and lead.  The brook is more slow flowing at these locations, where
it broadens into a poorly defined channel, and this area may act as a contaminant sink.   Surface water
was also screened for parameters such as pH, conductivity, turbidity, dissolved oxygen,  and temperature.
Conventional parameters, such as total suspended and dissolved solids, hardness, nitrogen, phosphorous,
and chloride were also analyzed.  In the majority of samples, the conventional parameters yielded values
typical of drinking water and appear to correlate with high total suspended solids present at locations
such as SW012 and SW014.  The pH was found to be near neutral, thus low metal solubility would be

-------
expected.

Heavy metals are the primarily inorganic contaminants of concern for surface water at the site.  The
dominant fate and transport process for heavy metals in surface water are sorption and precipitation.

The statistical analysis performed on the surface water data indicated that the most common naturally
occurring metals were strongly correlated:  calcium, magnesium, sodium,  potassium, iron, and manganese:
these chemicals which behave similarly in the environment, were found in proportional guantities at the
same location.  These metals normally exhibit high concentrations in the environment and, in fact,  from
this group, only iron exceeded secondary water guality standards. The strong correlation in this group
may indicate a natural origin for each of these metals. Distribution of other compounds was found to be
random.  The surface water data also demonstrated a positive spatial correlation through which three
clusters of sampling locations were identified that exhibit the similar chemical characteristics.  One
large cluster contained all surface water samples nearest to the landfill and most samples downstream.  A
second large cluster contained more distant surface water samples in the unnamed stream and Nine Foot
Brook, along with the background samples.  The third and smallest cluster was composed of wetland samples
further downstream from the landfill.  This pattern seems to correspond with the groundwater flow paths
and discharge patterns,  indicating that the groundwater is likely to have some influence on surface water
contaminant levels.

Three rounds of sediment sampling were performed in 1992 and 1994,  generally at locations coinciding with
surface water sampling.   All sediment samples were analyzed for VOCs, SVOCs, pesticides, PCBs, and
inorganics.  Similar to surface waters, volatiles were infreguently detected in sediment samples, most
below 50 ppb.  Compounds detected above 50 ppb, mostly at a single location, include toluene, 2-butanone,
and acetone.  Several various SVOCs were detected, including PAHs at most locations, including
background.  Other SVOCs detected at some locations include phthalates,  dichlorobenzenes, naphthalenes,
and phenols at levels mostly below 100 ppb, with highest concentrations ranging up to 1,400 ppb to the
east of the landfill.  Total PAH concentrations did not exceed the Ontario Ministry of Environment (MOE)
sediment criteria at any locations.  MOE sediment criteria established as guidelines for the protection
of ecological receptors from exposure to contaminated sediments.  Also,  none of the individual compounds
exceeded the corresponding criteria for that compound.

Several pesticides were detected at up to nine locations, mostly at trace levels,  with none exceeding 100
ppb.  The greatest number of seven pesticides  (six) were found at a sampling location near the confluence
of the unnamed stream and Nine Foot Brook.  It appears that trace levels of pesticides are clustered in
sediments in and around the downgradient standing waters.  Agricultural areas, including a former apple
orchard approximately 1/4 mile southeast, may be the contributing source to this area.  PCBs were
detected during the Round 3 at five locations with the highest level of 34 ppb on the west side of the
landfill in the proximity of stained surface soils.  Overall,  phthalates, pesticides, and PAHs were most
prevalent to the west and southeast of the landfill.

Inorganic compound found to exceed MOE criteria in the background sediment samples were lead, detected in
all four locations, iron, and magnesium.  Arsenic, copper, iron, lead,  manganese,  mercury, and zinc were
found exceeding MOE criteria in a few samples either along the unnamed stream or the Nine Foot Brook,
with most MOE exceedances in an area with standing water at the confluence of the Nine Foot Brook and the
unnamed stream.  In general, the inorganics were more prevalent, with many exceeding background
concentrations, in the areas adjacent to the landfill near the leachate seeps, and were diminishing
further downstream.  High total organic carbon (TOG) values and high fine content in these sediments
indicate that the sediments will tend to retain and absorb organic and inorganic chemicals.

The dominant fate and transport mechanism for PAHs, pesticides, and inorganics in sediment is absorption.
Statistical analysis of the sediment data showed no chemical compound correlation, indicating random
distribution of these compounds.  However, cluster analysis yielded two sample clusters indicating one
cluster with a common set of background conditions.  The second cluster was composed of samples near the
west landfill toe, one sample east of the landfill, and downstream samples in the wetlands.  This
analysis indicates a tendency for transport and deposition of contaminants in the area adjacent to the
landfill, near the unnamed stream and its associated wetlands.

     D.   Air

Landfill gas characterization was conducted to identify areas in the landfill containing elevated
concentrations of volatile organic compounds that indicate source areas.  In addition, an air guality
dispersion analysis was performed for over 30 VOCs to determine possible impacts from the Davis GSR
Landfill on the nearby receptors.  The worst-case existing toxic air pollutant concentrations from the
landfill gas monitoring program were incorporated into the modeling and the resultant highest predicted
off-site ambient concentrations were compared to the Rhode Island Annual Acceptable Ambient Levels.  The

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highest off-site VOC concentrations were found to occur at the Landfill Area A northeast property
boundary, near the Davis residence, however, none of the VOCs exceeded RIDEM AALs at either the property
boundary or at the Davis residence.

VI.   SUMMARY OF SITE RISKS

     A.   Human Health Risk Assessment

A baseline Human Health Risk Assessment  (HHRA) was completed in accordance with EPA's RI/FS streamlined
approach and guidance for landfills (USEPA, 1991).  The HHRA and ecological risk assessments were
performed to estimate the probability and magnitude of potential adverse effects from exposure to
contaminants associated with the Site.  The public health risk assessment followed a four step process:
1) contaminant identification, which identified those hazardous substances which, given the specifics of
the site were of significant concern;  2) exposure assessment, which identified actual or potential
exposure pathways, characterized the potentially exposed populations, and determined the extent of
possible exposure; 3) toxicity assessment, which considered the types and magnitude of adverse health
effects associated with exposure to hazardous substances, and 4) risk characterization, which integrated
the three earlier steps to summarize the potential and actual risks posed by hazardous substances at the
site, including carcinogenic and non-carcinogenic risks.  The results of the public health risk
assessment for the Davis GSR Landfill Superfund Site are discussed below followed by the conclusions of
the environmental risk assessment.

Thirty-nine contaminants of concern, listed in Table B-l through B-9 in Appendix B of this Record of
Decision were selected for evaluation in the risk assessment.  These contaminants constitute a
representative subset of all the contaminants identified at the Site during the Remedial Investigation.
The 39 contaminants of concern were selected to represent potential site related hazards based on
toxicity, concentration, frequency of detection, and mobility and persistence in the environment.  A
summary of the health effects of each of the contaminants of concern can be found in Appendix G of the
Davis GSR Landfill Final Remedial Investigation Report, Volume III, November, 1994.

Potential human health effects associated with exposure to the contaminants of concern were estimated
quantitatively or qualitatively through the development of several hypothetical exposure pathways.  These
pathways were developed to reflect the potential for exposure to hazardous substances based on the
present uses, potential future uses, and location of the Site.  The Davis GSR Landfill site consists of
58 acres.  Of this 58 acres, approximately 21 acres consist of a landfill portion and 20 acres consisting
of wetlands.  The landfill is currently inactive and has not been closed or capped in accordance with
state or federal regulations.  Land within 1 mile of the site is predominantly wooded with various
wetlands and some cleared areas.  Developed land within 1 mile of the site is characterized by low
density residential use and recreational farming.  Approximately 50 residences are located within this
1-mile radius on Tarkiln Road, Evans Road, Eddy Road, and small portions of Mann School Road, Burlingame
Road, and Farnum Road.  The closest four residences to the site are within 0.5 mile of the site.  Future
uses of the site are expected to prohibit residential development in the immediate area if the site
(Figure 13).

The following is a brief summary of the exposure pathways evaluated.  A more detailed description can be
found in Section 10.4.2 of the Davis GSR Landfill Final Remedial Investigation Report, Volume 1,
November, 1994.  For contaminated groundwater, a lifetime of consuming 2 liters per day was presumed
(future residential exposure scenario).   Incidental ingestion and dermal contact with surface water was
evaluated to reflect exposure to an adolescent who may wade and play in the Nine Foot Brook, unnamed
stream and associated wetlands for 36 days/year for 12 years  (current and future trespasser exposure
scenario for recreational activities).  Incidental ingestion of sediments was evaluated for the same
receptor in the same areas as for surface water.  Dermal contact with aqueous leachate and ingestion of
the dermal contact with leachate soils by a child trespasser were evaluated for an exposure frequency of
36 days/year for 12 years.  Dermal contact and incidental ingestion of surface soils was evaluated for a
child of 1-6 years, who may be exposed 36 days per year for 12 years.  Dermal contact and incidental
ingestion of subsurface soils was evaluated for a future construction worker who may be exposed 250
days/yr for 1 year.  For the inhalation pathway, a dispersion model was used to predict the highest
ambient air concentrations at the nearest off-site location.  The model prediction was used to evaluate
potential exposures to current and future residential adults who may spend 30 years breathing the
predicted air concentrations.  In addition, exposures to an on-site adolescent trespasser who might be
exposed to landfill gases for 36 days/yr for 12 years, was evaluated.  For each pathway evaluated, an
average and a reasonable maximum exposure estimate was generated corresponding to exposure to the average
and the maximum concentration detected in that particular medium.

Excess lifetime cancer risks were determined for each exposure pathway by multiplying the exposure level
with the chemical specific cancer factor.  Cancer potency factors have been developed by EPA from

-------
epidemiological or animal studies to reflect a conservative "upper bound" of the risk posed by
potentially carcinogenic compounds.  That is, the true risk is unlikely to be greater than the risk
predicted.  The resulting risk estimates are expressed in scientific notation as a probability (e.g. 1 x
10-6 for 1/1,000,000) and indicate (using this example),  that an average individual is not likely to have
greater that a one in a million chance of developing cancer over 70 years as a result of site-related
exposure as defined to the compound at the stated concentration.  Current EPA practice considers
carcinogenic risks to be additive when assessing exposure to a mixture of hazardous substances.

The hazard index was also calculated for each pathway as EPA's measure of the potential for
non-carcinogenic health effects.  A hazard guotient is calculated by dividing the exposure level by the
reference dose (RfD) or other suitable benchmark for non-carcinogenic health effects for an individual
compound.  Reference doses have been developed by EPA to protect sensitive individuals over the course of
a lifetime and they reflect a daily exposure level that is likely to be without an appreciable risk of an
adverse health effect.  RfDs are derived from epidemiological or animal studies and incorporate
uncertainty factors to help ensure that adverse health effects will not occur. The hazard guotient is
often expressed as a single value  (e.g. 0.3)  indicating the ratio of the stated exposure as defined to
the reference dose value (in this example, the exposure as characterized is approximately one third of an
acceptable exposure level for the given compound).  The hazard guotient is only considered additive for
compounds that have the same or similar toxic endpoint and the sum is referred to as the hazard index
(HI).   For example:  the hazard guotient for a compound known to produce liver damage should not be added
to a second whose toxic endpoint is kidney damage.

Tables 1 through 13 below depict the carcinogenic and noncarcinogenic risk summaries for each media
evaluated.  Table 1 depicts the carcinogenic and noncarcinogenic risk summary for the contaminants of
concern in off-landfill (on-site) overburden and bedrock groundwater evaluated to reflect the potential
future ingestion of groundwater corresponding to the average and the reasonable maximum exposure  (RME)
scenarios.  Table 2 depicts the carcinogenic and noncarcinogenic risk summary for the contaminants of
concern in surface water in Landfill Area B and off-landfill areas evaluated to reflect a potential
current exposure via incidental ingestion corresponding to the average and the reasonable maximum
exposure  (RME) scenarios.   Table 3 depicts the carcinogenic and noncarcinogenic risk summary for the
contaminants of concern in surface waters evaluated to reflect the current dermal exposures corresponding
to the average and the reasonable maximum exposure (RME)  scenarios.  Table 4 depicts the carcinogenic and
noncarcinogenic risk summary for the contaminants of concern in sediments in Landfill Area B and
off-landfill areas evaluated to reflect a potential current exposure via incidental ingestion
corresponding to the average and the reasonable maximum exposure (RME) scenarios.  Table 5 depicts the
carcinogenic and noncarcinogenic risk summary for the contaminants of concern in agueous leachate
evaluated to reflect the current dermal exposures corresponding to the average and the reasonable maximum
exposure  (RME) scenarios.  Table 6 depicts the carcinogenic and noncarcinogenic risk summary for the
contaminants of concern in leachate soil evaluated to reflect a potential current exposure via incidental
ingestion corresponding to the average and the reasonable maximum exposure (RME) scenarios.  Table 7
depicts the carcinogenic and noncarcinogenic risk summary for the contaminants of concern in leachate
soil evaluated to reflect a potential current exposure via dermal contact corresponding to the average
and the reasonable maximum exposure (RME) scenarios.   Table 8 depicts the carcinogenic and
noncarcinogenic risk summary for the contaminants of concern in surficial soil in Landfill Area A, B and
off-landfill, evaluated to reflect a potential current exposure via incidental ingestion corresponding to
the average and the reasonable maximum exposure  (RME) scenarios. Table 9 depicts the carcinogenic and
noncarcinogenic risk summary for the contaminants of concern in surficial soil in Landfill Areas A, B and
off-landfill, evaluated to reflect a potential current exposure via dermal contact corresponding to the
average and the reasonable maximum exposure  (RME) scenarios.  Table 10 depicts the carcinogenic and
noncarcinogenic risk summary for the contaminants of concern in off-landfill boring soils, evaluated to
reflect a potential future exposure via incidental ingestion corresponding to the average and the
reasonable maximum exposure (RME)scenarios.   Table 11 depicts the carcinogenic and noncarcinogenic risk
summary for the contaminants of concern in off-landfill boring soils, evaluated to reflect a potential
future exposure via dermal contact corresponding to the average and the reasonable maximum exposure (RME)
scenarios.  Table 12 depicts the carcinogenic and noncarcinogenic risk summary for the contaminants of
concern in on-site landfill gas, evaluated to reflect a potential current and future exposure via
inhalation corresponding to the average and the reasonable maximum exposure (RME) scenarios.  Table 13
depicts the carcinogenic and noncarcinogenic risk summary for the  contaminants of concern in off-site
landfill gas, evaluated to reflect a potential current and future exposure via inhalation corresponding
to the average and the reasonable maximum exposure (RME)  scenarios.

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                                                                                                 Table 1
                                                                                                                                      Page  1 of  4
OFF-LANDFILL OVERBURDEN
                                                                                           DAVIS GSR LANDFILL SITE
                                                                                    FUTURE GROUNDWATER INGESTION PATHWAY
                                                                                       CARCINOGENIC RISKS TO RESIDENTS
Contaminants of Concern
Volatile Organic Compounds
Benzene

Semivolatile Organic Compounds
1,2,4-Trimethylbenzene
1,3,5-Trimethylbenzene

Inorganics
Arsenic
Barium
Beryllium
Chromium
Lead
Manganese
Nickel
  Concentration
Average  Maximum
     (mg/1)
0.0015    0.008
Exposure Factor
    Adult
 (1/kg/day)
                          1.2E-02
 Exposure Dose
Average     RME
   (mg/kg/day)
                                         1.8E-05   9.4E-05
    Cancer
 Slope  Factor
(mg/kg/day) -1
                                                               2.9E-02
 Weight        RISK ESTIMATE
  of         Average       RME
Evidence      Adult       Adult
                                                                                 A
                                                                                           5.1E-07
                                                                                                       2.7E-06
0,

0,
0,
0,

0,
0,
0,
.0006
ND
.0029
.085
.00093
ND
.0029
.7
.011
0

0
0
0

0
3
0
.001
ND
.013
.288
.0013
ND
.0131
.42
.061
1
1
1
1
1
1
1
1
1
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
7

3
1
1

3
8
1
.OE-02
	
.4E-05
.OE-03
.IE-OS
--
.4E-05
.4E-03
.3E-04
1.

1.
3,
1.

1.
4,
7,
.2E-05
— —
.5E-04 1.5E+00
. 4E-03
.5E-05 4.3E+00
--
.5E-04
. 1E-02
.2E-04
D
D
A
—
B2
--
B2
D
A(inh)
—
— —
5.1E-05 2.3E-04
_
4.7E-05 6.6E-05
--
—
—
—
                                                                                                              SUM
                                                                                                                            9.9E-05    3.0E-04
Exposure Factor:
  Adults - 2 liters of water per day for 350 days in a 365 day year for 30 years in a 70 year lifetime by
a 70 kg adult = 0.012 liter per kg body weight per day

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                                                                                        Table 1  (cont'd)
                                                                                                         Page 2 of 4
OFF-LANDFILL OVERBURDEN
                                                                                      DAVIS GSR LANDFILL SITE
                                                                               FUTURE GROUNDWATER INGESTION PATHWAY
                                                                                NONCARCINOGENIC RISKS TO RESIDENTS
Contaminants of Concern
    Adult
               Adult
Volatile Organic Compounds
Benzene

Semivolatile Organic Compounds
1,2, 4-Trimethylbenzene
1,3,5-Trimethylbenzene

Inorganics
Arsenic
Barium
Beryllium
Chromium
Lead
Manganese
Nickel
  Concentration
Average    Maximum
       (mg/1)
0.0015
0.0006
  ND
0.0029
0.085
0.00093
  ND
0.0029
0.7
0.011
            0.008
0.001
  ND
0.013
0.288
0.0013
  ND
0.0131
3.42
0.061
              Exposure Factor
                   Adult
                (1/kg/day)
                              2.7E-02
2.7E-02
2.7E-02
2.7E-02
2.7E-02
2.7E-02
2.7E-02
2.7E-02
2.7E-02
2.7E-02
                    Exposure Dose
                  Average       RME
                     (mg/kg/day)
                                                4.1E-05    2.2E-04
                                                1.6E-05    2.7E-05
7.9E-04
2.3E-03
2.5E-05

7.9E-05
1.9E-02
3.0E-04
3.6E-04
7.9E-03
3.6E-05

3.6E-04
9.4E-02
1.7E-03
                         Reference
                          Dose
                        (mg/kg/day)
                        5.0E-02
                         5.0E-02
3.0E-04
7.0E-02
5.0E-03
l.OE+00
2.3E-02
2.0E-02
Toxicity
Endpoint
CNS
CNS
Skin
Cardiovasc.
None
None
CNS
CNS
Organ Wt .
SUM
CNS
Skin
Cardiovasc.
HAZARD
Average
3.3E-04
—
2.6E-01
3.3E-02
5.1E-03
—
—
8.3E-01
1.5E-01
1.2
0.83
0.26
0.033
INDEX
RME
5.5E-04
—
1.2E+00
1.1E-01
7.1E-03
—
—
4.1E+00
8.4E-02
5.5
4.1
1.2
0.11
Exposure Factor:
  Adults - 2 liters of water per day for 350 days in a 365 day year by a 70 kg adult = 0.027 liter per kg body weight per day.

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                                                                                              Table 1  (cont'd)
                                                                                                         Page 3 of 4
OFF-LANDFILL BEDROCK
                                                                                          DAVIS GSR LANDFILL SITE
                                                                                    FUTURE GROUNDWATER INGESTION PATHWAY
                                                                                       CARCINOGENIC RISKS TO RESIDENTS
Contaminants of Concern
Volatile Organic Compounds
Benzene
  Concentration
Average    Maximum
       (mg/1)
                                  0.0035
                                              0.0089
Exposure Factor
    Adult
  (1/kg/day)
                                                               1.2E-02
  Exposure Dose
Average      RME
    (mg/kg/day)
                                                                                  4.1E-05
                                                                                             l.OE-04
    Cancer      Weight
Slope Factor      of
(mg/kg/day)-1  Evidence
                                                                                                           2.9E-02
                                                                                                                          A
 RISK ESTIMATE
Average     RME
 Adult     Adult
                                                                                                                                    1.2E-06   3.0E-06
Semivolatile Organic Compounds
1,2,4-Trimethylbenzene
1,3, 5-Trimethylbenzene

Inorganics
Arsenic
Barium
Beryllium
Chromium
Lead
Manganese
Nickel
0,
0,
0,
0,
0,
0,
0,
1.
0,
.0007
.0009
.0064
.21
.00042
.028
.0039
.7
.032
0,
0,
0,
0,
0,
0,
0,
4,
0,
.0016
.003
.03
.658
.00045
.167
.0173
.28
.127
1.
1.
1.
1.
1.
1.
1.
1.
1.
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
.2E-02
8,
1.
7,
2,
4,

4,
2,
3,
.2E-06
. IE-OS
.5E-04
.5E-03
. 9E-06
--
. 6E-05
. OE-02
. 8E-04
1.
3,
3,
7,
5,

2,
5,
1.
. 9E-05
.5E-05
.5E-04
.7E-03
.3E-06
-
. OE-04
. 1E-02
.5E-03
D
D
1.50E+00 A
—
4.3E+00 B2
--
B2
D
A(inh)
                                                                                                  1.1E-04   5.3E-04

                                                                                                  2.1E-05   2.3E-05
                                                                                                                          SUM
                                                                                                                                     1.4E-04  5.5E-04
Exposure Factor:
  Adults - 2 liters of water per day for 350 days in a 365 day year for 30 years in a 70 year lifetime by
a 70 kg adult = 0.012 liters per kg body weight per day.

-------
                                                                                            Table 1  (cont'd)
                                                                                                         Page 4 of 4
OFF-LANDFILL BEDROCK
                                                                                             DAVIS GSR LANDFILL SITE
                                                                                      FUTURE GROUNDWATER INGESTION PATHWAY
                                                                                       NONCARCINOGENIC RISKS TO RESIDENTS
Contaminants of Concern
Volatile Organic Compounds
Benzene
  Concentration
Average    Maximum
       (mg/1)
                                  0.0035
                                              0.0089
Exposure Factor
    Adult
  (1/kg/day)
                                                               2.7E-02
  Exposure Dose
Average      RME
    (mg/kg/day)
                                                                                  9.6E-05
                                                                                             2.4E-04
 Reference
  Dose
(mg/kg/day)
Toxicity
Endpoint
Semivolatile Organic Compounds
1,2,4-Trimethylbenzene
1,3,5-Trimethylbenzene

Inorganics
Arsenic
Barium
Beryllium
Chromium
Lead
Manganese
Nickel
0.0007
0.0009
0.0064
0.21
0.00042
0.028
0.0039
1.7
0.032
0,
0,
0,
0,
0,
0,
0,
4,
0,
.0016
.003
.03
.658
.00045
.167
.0173
.28
.127
2,
2,
2,
2,
2,
2,
2,
2,
2,
.7E-02
. 7E-02
.7E-02
. 7E-02
.7E-02
.7E-02
.7E-02
. 7E-02
.7E-02
1.
2,
1.
5,
1.

1.
4,
8,
. 9E-05
.5E-05
. 8E-04
. 8E-03
.2E-05
--
. 1E-04
. 7E-02
. 8E-04
4,
8,
8,
1.
1.

4,
1.
4,
. 4E-05
.2E-05
.2E-04
. 8E-02
.2E-05
--
.7E-04
.2E-01
.7E-04
5.0E-02
5.0E-02
3.0E-04
7.0E-02
5.0E-03
l.OE+00

2.3E-02
2.0E-02
CNS
CNS
Skin
Cardiovasc.
None
None
CNS
CNS
Organ Wt .
3
4
5
8
2


2
4
.8E-04
.9E-04
.8E-01
.2E-02
.3E-03
—
—
.OE+00
.4E-02
8.8E-04
1.6E-03
2.7E+00
2.6E-01
2.5E-03
--
—
5.1E+00
2.4E-02
                                                                                                                              SUM
                                                                                                                              CNS
                                                                                                                              Skin
                                                                                                                              Cardiovasc.
Exposure Factor:
  Adults - 2 liters of water per day for 350 days in a 365 day year by a 70 kg adult = 0.027 liter per kg body weight per day

-------
                                                                           TABIiE 2
                                                                                                                                  Page 1 of 2
                                                                DAVIS  GSR LANDFILL SITE
                                                       CURRENT  SURFACE WATER INGESTION PATHWAY
Landfill Area B
                                                       CARCINOGENIC  RISKS  TO CHILD TRESPASSERS
Concentration
Contaminants
of Concern
Inorganics
Antimony
Arsenic
Barium
Beryllium
Lead
Manganese
Vanadium

Exposure Factor = 0.
a 365 day year for 12
Landfill Area B
Average
(mg/1)

ND
ND
0.061
ND
0.012
2.3
ND

05 of liters of
Exposure
Maximum Factor


ND
ND
0.104
ND
0.022
4.39
ND

water
(1/kg/day)

2.0E-05
2.0E-05
2.0E-05
2.0E-05
2.0E-05
2.0E-05
2.0E-05

ingested per hour
years in a 70 year lifetime by a 43 kg
NONCARCINOGENIC RISKS
Concentration
HAZARD INDEX
Contaminants
of Concern
Inorganics
Antimony
Arsenic
Barium
Beryllium
Lead
Manganese
Vanadium

Average
(mg/1)

ND
ND
0.061
ND
0.012
2.3
ND

Maximum


ND
ND
0.104
ND
0.022
4.39
ND
Exposure

Factor
(1/kg/day)

1.2E-04
1.2E-04
1.2E-04
1.2E-04
1.2E-04
1.2E-04
1.2E-04
Exposure Dose
Average Maximum
(mg/kg/day)

—
—
1.2E-06 2.1E-06
--
2.4E-07 4.4E-07
4.6E-05 8.8E-05
__

for 1 hour per day
child = 2.0 x 10-5
Slope Care. CANCER ESTIMATE
Factor Weight of Average
(mg/kg/day) -1 Evidence

—
1.5E+00 A
—
4.3E+00 B2
B2
D
D
SUM
for 36 days per year in
1/kg/day.
RME


—
—
—
--
—
--
--
--


TO CHILD TRESPASSERS
Exposure Dose

Average RME
(mg/kg/day)

—
—
7.3E-06 1.2E-05
--
1.4E-06 2.6E-06
2.8E-04 5.3E-04
—
Reference Toxicity

Dose Endpoint Average
(mg/kg/day)

4.0E-04 Blood
3.0E-04 Skin
7.0E-02 Cardiovasc.l.OE-04
5.0E-03 None
CNS
2.3E-02 CNS 1.2E-02
7.0E-03 Liver


RME


—
—
1.8E-04
--
—
2.3E-02
-
                                                                                                       SUM
                                                                                                                 0.012
                                                                                                                            0.02
  Exposure Factor = 0.05 of liters of water ingested per hour  for  1  hour  per day for 36 days per year in
a 365 day year by a 43 kg child =  1.2 x 10-4 1/kg/day.

-------
                                                                     TABIiE  2  (cont'd)
Page 2 of 2
                                                               DAVIS  GSR LANDFILL SITE
                                                       CURRENT SURFACE WATER INGESTION PATHWAY
Off-Landfill
                                                       CARCINOGENIC  RISKS  TO CHILD TRESPASSERS

Contaminants
of Concern
Inorganics
Antimony
Arsenic
Barium
Beryllium
Lead
Manganese
Vanadium

Exposure Factor = 0.
lifetime by a 43 kg
Off -Landfill

Contaminants
of Concern
Inorganics
Antimony
Arsenic
Barium
Beryllium
Lead
Manganese
Vanadium
Concentration
Average Maximum
(mg/1)

0.025 0.06
0.002 0.0119
0.088 0.544
0.001 0.005
0.016 0.171
1 6.46
0.0093 0.0682

Exposure
Factor
(1/kg/day)

2.0E-05
2.0E-05
2.0E-05
2.0E-05
2.0E-05
2.0E-05
2.0E-05

05 of liters of water ingested per hour
Exposure Dose
Average RME
(mg/kg/day)

5.0E-07 1.2E-06
4.0E-08 2.4E-07
1.8E-06 1.1E-05
2.0E-08 l.OE-07
3.2E-07 3.4E-06
2.0E-05 1.3E-04
1.9E-07 1.4E-06

for 1 hour per day
Slope
Factor
(mg/kg/day) -1

—
1.5E+00
—
4.3E+00
—
--
--

Care. CANCER ESTIMATE
Weight of Average
Evidence

—
A 6.0E-08
—
B2 8.6E-08
B2
D
D
SUM 1.5E-07
for 36 days per year in a 365 day year
RME


—
3.6E-07
—
4.3E-07
—
--
--
7.9E-07
for 12 years in a 70 year
child = 2.0 x 10-5 I/kg/ day.

Concentration
Average Maximum
(mg/1)

0.025 0.06
0.002 0.0119
0.088 0.544
0.001 0.005
0.012 0.171
1 6.46
0.0093 0.0682

Exposure
Factor
(1/kg/day)

1.2E-04
1.2E-04
1.2E-04
1.2E-04
1.2E-04
1.2E-04
1.2E-04
NONCARCINOGENIC
Exposure Dose
Average RME
(mg/kg/day)

3.0E-06 7.2E-06
2.4E-07 1.4E-06
1.1E-05 6.5E-05
1.2E-07 6.0E-07
1.9E-06 2.1E-06
1.2E-04 7.8E-04
1.1E-06 8.2E-06
RISKS TO CHILD
Reference
Dose
(mg/kg/day)

4.0E-04
3.0E-04
7.0E-02
5.0E-03
—
2.3E-02
7.0E-03
TRESPASSERS
Toxicity HAZARD
Endpoint Average


Blood 7.5E-03
Skin 8.0E-04
Cardiovascl . 5E-04
None 2.4E-05
CNS
CNS 5.2E-03
Liver 1.6E-04

INDEX
RME


1.8E-02
4.8E-03
9.3E-04
1.2E-04
—
3.4E-02
1.2E-03
                                                                                                       SUM
                                                                                                                 0.014
                                                                                                                             0.06
   Exposure Factor = 0.05 of liters of water ingested per hour  for  1  hour  per day for 36 days per year in a 365 day year by a 43 kg child
   1.2 x 10-4 1/kg/day

-------
Landfill Area B
                 TABIiE 3

           DAVIS GSR LANDFILL SITE
CURRENT SURFACE WATER DERMAL CONTACT PATHWAY

  CARCINOGENIC RISKS TO CHILD TRESPASSERS
                                                                                                                                                                    Page 1 of 2
Concentration
Contaminants
of Concern
Inorganics
Antimony
Arsenic
Barium
Beryllium
Lead
Manganese
Vanadium

Exposure Factor
0.79 cm2-event/kg.
Landfill Area B
Contaminants
of Concern
Inorganics
Antimony
Arsenic
Barium
Beryllium
Lead
Manganese
Vanadium
Average
(mg/1)

ND
ND
0.061
ND
0.012
2.3
ND

Maximum


ND
ND
0.104
ND
0.022
4.39
ND

= 2000 cm2 skin surface


Kp
(cm/hr)

0.001
0.001
0.001
0.001
0.001
0.001
0.001

area for

Concentration
Average
(mg/1)

ND
ND
0.061
ND
0.012
2.3
ND
Maximum


ND
ND
0.104
ND
0.022
4.39
ND
Kp
(cm/hr)

0.001
0.001
0.001
0.001
0.001
0.001
0.001
t event
(hr/ event)

1
1
1
1
1
1
1

Conversion
Factor
(l/cm3)

l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03

DAevent
Average RME
(mg/cm2- event)

—
—
6.1E-08 l.OE-07
--
1.2E-08 2.2E-08
2.3E-06 4.4E-06
__

Exposure
Factor
(cm2- event /kg-day)

0.79
0.79
0.79
0.79
0.79
0.79
0.79

contact per event for 1 event/day for 36 days per year in a 365


NONCARCINOGENIC
Conversion
t event
(hr/ event)

1
1
1
1
1
1
1
Factor
(l/cm3)

l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03


RISKS TO CHILD TRESPASSERS
DAevent Exposure
Average RME
Factor
(mg/cm2-event) (cm2-event/kg-day)

—
—
6.1E-08 l.OE-07
--
1.2E-08 2.2E-08
2.3E-06 4.4E-06
—

4.6
4.6
4.6
4.6
4.6
4.6
4.6
Exposure Dose
Average RME
(mg/kg/day)

-
—
4.8E-08 8.2E-08
-
9.5E-09 1.7E-08
1.8E-06 3.5E-06
-

Slope
Factor
(mg/kg/day) -1

—
1.5E+00
—
4.3E+00
—
-
--

day year for 12 years in a 70 year

Exposure Dose
Average RME
(mg/kg/day)

-
—
2.8E-07 4.8E-07
--
5.5E-08 l.OE-07
1.1E-05 2.0E-05
_

Reference
Dose
(mg/kg/day)

4.0E-04
3.0E-00
7.0E-02
5.0E-03
—
2.3E-02
7.0E-03
Care.
Weight of
Evidence

—
A
—
B2
B2
D
D
SUM
lifetime by a

Toxicity
Endpoint


Blood
Skin
Cardiovasc.
None
CNS
CNS
Liver
CANCER ESTIMATE
Average RME


—
—
—
--
—
-
__
--
43 kg child =

HAZARD INDEX
Average RME


—
—
4.0E-06 6.8E-06
--
—
4.6E-04 8.8E-04
—
                                                                                                                                                             SUM     0.0005    0.0009

   Exposure Factor = 2000 cm2 skin surface area for contact per  event  for  1  event/day for 36 days per year in a 365 day year by a 43 kg child = 4.6 cm2-event/kg/day.

-------
Off-Landfill
                TABLE 3(cont'd)

           DAVIS GSR LANDFILL SITE
CURRENT SURFACE WATER DERMAL CONTACT PATHWAY

  CARCINOGENIC RISKS TO CHILD TRESPASSERS
                                                                                                                                                                   Page 2 of 2
Concentration
Contaminants Average Maximum
of Concern (mg/1)
Inorganics
Antimony 0
Arsenic 0
Barium 0
Beryllium 0
Lead 0
Manganese
Vanadium 0

Exposure Factor =
0.79 cm2- event /kg/
Off-Landfill
.025
.002
.088
.001
.016
1
.0093

2000 cm2 skin

0.06
0.0119
0.544
0.005
0.171
6.46
0.0682

surface

Kp
(cm/hr)
0.001
0.001
0.001
0.001
0.001
0.001
0.001

area for

t event
(hr/ event)
1
1
1
1
1
1
1

contact per

Conversion
Factor
(l/cm3)
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03

event for 1

DAevent Exposure
Average RME Factor
(mg/cm2- event) (cm2- event /kg-day)
2.5E-08 6.0E-08
2.0E-09 1.2E-08
8.8E-08 5.4E-07
l.OE-09 5.0E-09
1.6E-08 1.7E-07
l.OE-06 6.5E-06
9.3E-09 6.8E-08

event/day for 36 days

NONCARCINOGENIC RISKS TO
Concentration
Contaminants Average Maximum
of Concern
Inorganics
Antimony
Arsenic
Barium
Beryllium
Lead
Manganese
Vanadium
(mg/1)

0.025 0
0.002 0
0.088 0
0.001 0
0.016 0
1 6
0.0093 0


.06
.0119
.544
.005
.171
.46
.0682
Kp
(cm/hr)

0.001
0.001
0.001
0.001
0.001
0.001
0.001
t event
(hr/ event)

1
1
1
1
1
1
1
Conversion
Factor
(l/cm3)

l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
DAevent
Average RME
0.79
0.79
0.79
0.79
0.79
0.79
0.79

per year in a 365

CHILD TRESPASSERS
Exposure
Factor
(mg/cm2-event) (cm2-event/kg-day)

2.5E-08 6.0E-08
2.0E-09 1.2E-08
8.8E-08 5.4E-07
l.OE-09 5.0E-09
1.6E-08 1.7E-07
l.OE-06 6.5E-06
9.3E-09 6.8E-08

4.6
4.6
4.6
4.6
4.6
4.6
4.6
Exposure Dose Slope Care.
Average RME Factor Weight of
(mg/kg/day) (mg/kg/day) -1 Evidence
2.0E-08 4.7E-08
1.6E-09 9.4E-09
7.0E-08 4.3E-07
7.9E-10 4.0E-09
1.3E-08 1.4E-07
7.9E-07 5.1E-06
7.3E-09 5.4E-08

—
1.5E+00
—
4.3E+00
—
—
—

day year for 12 years in a 70 year


Exposure Dose
Average RME
(mg/kg/day)

1.2E-07 2.8E-07
9.2E-09 5.5E-08
4.0E-07 2.5E-06
4.6E-09 2.3E-08
7.4E-08 7.9E-07
4.6E-06 3.0E-05
4.3E-08 3.1E-07


Reference
Dose
(mg/kg/day)

4.0E-04
3.0E-04
7.0E-02
5.0E-03
—
2.3E-02
7.0E-03
—
A
—
B2
B2
D
D
SUM
lifetime by


Toxicity
Endpoint


Blood
Skin
Cardiovasc.
None
CNS
CNS
Liver
CANCER ESTIMATE
Average RME
—
2.4E-09 1.4E-08
—
3.4E-09 1.7E-08
—
--
__
5.8E-09 3.1E-08
a 43 kg child =


HAZARD INDEX
Average RME


2.9E-04 6.9E-04
3.1E-05 1.8E-04
, 5.8E-06 3.6E-05
9.2E-07 4.6E-06
-
2.0E-04 1.3E-03
6.1E-06 4.5E-05
                                                                                                                                                            SUM      0.0005   0.0022

   Exposure Factor = 2000 cm2 skin surface area for contact per event for  1  event/day  for  36  days  per  year  in a 365  day year by a 43 kg child = 4.6 cm2-event/kg-day

-------
                                                                                                TABIiE 4
                                                                                                                                                 Page 1  of 4
Landfill Area B
                                                                                         DAVIS GSR LANDFILL  SITE
                                                                                     CURRENT SEDIMENT INGESTION PATHWAY
                                                                                  CARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Semi-Volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Inorganics
Antimony
Arsenic
Beryllium
Manganese
Thallium
Vanadium
   Concentration
Average    Maximum
       (mg/kg)
Exposure Factor
  Ingestion
 (kg/kg/day)
ND
ND
ND
ND
ND
ND
ND
ND
2.7
0.9
290
0.66
17
ND
ND
ND
ND
ND
ND
ND
ND
3.7
1.3
426
0.66
26
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
7.2E-08
  Exposure Dose
Average     RME
    (mg/kg/day)
                                               1.9E-07   2.7E-07
                                               6.5E-08   9.4E-08
                                               2.1E-05   3.1E-05
                                               4.8E-08   4.8E-08
                                               1.2E-06   1.9E-06
     Cancer
Slope Factor
  (mg/kg/day)-1
                                                                       1.5E+00
 Weight
   of
Evidence
7,
7,
7,
7,
7,
7,
7,
. 3E+00
.3E+00
. 3E+00
. 3E+00
.3E+00
. 3E+00
.3E+00
B2
B2
B2
B2
B2
B2
B2
                                                              A
                                                              B2
                                                              D
                                                              D
                                                              D
 RISK ESTIMATE
Average     RME
                                                  2.9E-07
                                                  2.8E-07
                                          4.0E-07
                                          4.0E-07
                                                                                                                                 SUM
                                                                                                                                          5.7E-07
                                                                                                                                                     J.OE-07
Exposure Factor:
  Ingestion - 200 mg of sediment ingested per day with 100% absorption for SVOCs and Inorganics for  36 days  in  a  365 day  year
  for 12 years in a 70 year lifetime by a 43 kg child and a conversion factor of kg/10+6 mg=7.2 x  10-8 kg  of soil per  kg  body weight  per  day.

-------
                                                                                              TABIiE  4   (cont'd)
                                                                                                        Page 2  of  4
Landfill Area B
                                                                                           DAVIS GSR LANDFILL  SITE
                                                                                      CURRENT SEDIMENT  INGESTION PATHWAY
                                                                                   NONCARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Semi-Volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Inorganics
Antimony
Arsenic
Beryllium
Manganese
Thallium
Vanadium
   Concentration
Average    Maximum
       (mg/kg)
Exposure Factor
  Ingestion
 (kg/kg/day)
ND
ND
ND
ND
ND
ND
ND
ND
2.7
0.9
290
0.66
17
ND
ND
ND
ND
ND
ND
ND
ND
3.7
1.3
426
0.66
26
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
  Exposure Dose
Average     RME
    (mg/kg/day)
                                               1.3E-06   1.7E-06
                                               4.2E-07   6.1E-07
                                               1.4E-04   2.0E-04
                                               3.1E-07   3.1E-07
                                               8.0E-06   1.2E-05
 Reference
 Dose
(mg/kg/day)
Toxicity
Endpoint
  HAZARD INDEX
Average     RME
4.0E-04
3.0E-04
5.0E-03
2.3E-02
8.0E-05
7.0E-03
Blood
Skin
None
CNS
Liver
Liver
—
4.2E-03
8.5E-05
5.9E-03
3.9E-03
1.1E-03

5.8E-03
1.2E-04
8.7E-03
3.9E-03
1.7E-03
                                                                                                                                 SUM
                                                                                                                                              0.015
                                                                                                                                                        0.020
Exposure Factor:
  Ingestion - 200 mg of sediment ingested per day with 100% absorption for SVOCs and Inorganics  for  36 days
  in a 365 day by a 43 kg child and a conversation factor of kg/10+6 mg = 4.7 x 10-7 kg of  soil  per  kg body weight per  day

-------
                                                                                          TABLE 4  (cont'd)
                                                                                                     Page 3 of 4
Off-Landfill
                                                                                      DAVIS GSR LANDFILL SITE
                                                                                  CURRENT SEDIMENT INGESTION PATHWAY
                                                                                CARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Semi-Volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Inorganics
Antimony
Arsenic
Beryllium
Manganese
Thallium
Vanadium
Zinc
   Concentration
Average    Maximum
       (mg/kg)
Exposure Factor
  Ingestion
 (kg/kg/day)
  Exposure Dose
Average     RME
    (mg/kg/day)
 RISK ESTIMATE
Average     RME
0.083
0.22
0.19
0.2
0.095
0.024
0.81
8.5
7.4
1.7
2016
1.5
17
52
0.083
0.3
0.19
0.2
0.095
0.024
0.89
23.3
31.4
4.7
15600
14
60.4
78
7
7
7
7
7
7
7
7
7
7
7
7
7
7
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
6.
1.
1.
1.
6.
1.
5.
6.
5.
1.
1.
1.
1.
3.
OE-09
6E-08
4E-08
4E-08
8E-09
7E-09
8E-08
1E-07
3E-07
2E-07
5E-04
1E-07
2E-06
7E-06
6. OE-09
2.2E-08
1.4E-08
1.4E-08
6.8E-09
1.7E-09
1.7E-09
1.7E-06
2.3E-06
3.4E-07
1.1E-03
l.OE-06
4.3E-06
5.6E-06
7,
7,
7,
7,
7,
7,
6,







. 3E+00
.3E+00
. 3E+00
. 3E+00
.3E+00
. 3E+00
.4E-08

1.5E+00
4.3E+00
—
--
—
--
B2
B2
B2
B2
B2
B2
B2
D
A
B2
D
A(inh)
D
D
4.4E-08
1.2E-07
l.OE-07
1.1E-07
5.0E-08
1.3E-08
4.3E-07

8.0E-07
5.3E-07
—
—
—
—
4.4E-08
1.6E-07
l.OE-07
1.1E-07
5.0E-08
1.3E-08
4.7E-07

3.4E-06
1.5E-06
—
--
—
--
                                                                                                                                SUM
                                                                                                                                          1.8E-06
                                                                                                                                                      5.3E-06
Exposure Factor:
  Ingestion - 200 mg of sediment ingested per day with 100% absorption for SVOCs and Inorganics for 36 days
  in a 365 day year for 12 years in a 70 year lifetime by a 43 kg child and a conversion of kg/10+6 mg=7.2 x 10-f
                                                                          kg of soil per kg body weight per day

-------
                                                                                                     TABIiE  4  (cont'd)
                                                                                                          Page 4  of 4
Off-Landfill
                                                                                                 DAVIS  GSR LANDFILL SITE
                                                                                           CURRENT  SEDIMENT INGESTION PATHWAY
                                                                                        NONCARCINOGENIC RISKS  TO CHILD TRESPASSER
Contaminants of Concern
Semi-Volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Inorganics
Antimony
Arsenic
Beryllium
Manganese
Thallium
Vanadium
Zinc
   Concentration
Average    Maximum
       (mg/kg)
Exposure Factor
  Ingestion
 (kg/kg/day)
  Exposure Dose
Average     RME
    (mg/kg/day)
 Reference
  Dose
(mg/kg/day)
Toxicity
Endpoint
  HAZARD INDEX
Average     RME
0.083
0.22
0.19
0.2
0.095
0.024
0.81
8.5
7.4
1.7
2016
1.5
17
52
0.083
0.3
0.19
0.2
0.095
0.024
0.89
23.3
31.3
4.7
15600
14
60.4
78
4
4
4
4
4
4
4
4
4
4
4
4
4
4
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
3.9E-08
l.OE-07
8.9E-08
9.4E-08
4.5E-08
1.1E-08
3
4.
3.
8.
9.
7.
8.
2.
.8E-07
OE-06
5E-06
OE-07
5E-04
1E-07
OE-06
4E-05
3.9E-08
1.4E-07
8.9E-08
9.4E-08
4.5E-08
1.1E-08
4.2E-07
1.1E-05
1.5E-05
2.2E-06
7.3E-03
6.6E-06
2.8E-05
3.7E-05


4.
3.
5.
2.
8.
7.
3.
I
—
, OE-04
, OE-04
, OE-03
,3E-02
, OE-05
, OE-03
. OE-01
I
—
Blood
Skin
None
CNS
Liver
Liver
Blood
I
—
l.OE-02
1.2E-02
1.6E-04
4.1E-02
8.8E-03
1.1E-03
8.1E-05
I
—
2.7E-02
4.9E-02
4.4E-04
3.2E-01
8.2E-02
4.1E-03
1.2E-04
Exposure Factor:
  Ingestion - 200 mg of sediment ingested per day with 100% absorption for  SVOCs  and  Inorganics  for  36  days
  in a 365 day by a 43 kg child and a conversion factor of kg/10+6 mg =  4.7 x  10-7  kg of  soil per  kg body  weight  per day.
                                                                                                                                             0.073
                                                                                                                                                       0.48

-------
                                                                                                     TABIiE 5
                                                                                              DAVIS GSR LANDFILL SITE
                                                                                   CURRENT LEACHATE AQUEOUS DERMAL CONTACT PATHWAY

                                                                                      CARCINOGENIC RISKS TO CHILD TRESPASSERS
Landfill Area A
Concentration
Contaminants
of Concern
Inorganics
Antimony
Arsenic
Barium
Lead
Manganese
Nickel

Exposure Factor
0.79 cm2-event/kg

Landfill Area A
Average


0.0136
0.0036
0.758
0.0191
1.69
0.0987

Maximum
(mg/1)

0.0136
0.0036
0.758
0.0191
1.69
0.0987

= 2000 cm2 skin surface






Kp
t event
Conversion DAevent
Factor
Average RME
Exposure
Factor
Exposure Dose
Average RME
(cm/hr) (hr/event) (l/cm3) (mg/cm2- event) (cm2-event/kg-day) (mg/kg/day)

0.001
0.001
0.001
0.001
0.001
0.001

area for




1
1
1
1
1
1

contact per



Concentration
Contaminants
of Concern
Inorganics
Antimony
Arsenic
Barium
Lead
Manganese
Nickel
Average
(mg/1)

0.0136
0.0036
0.758
0.0191
1.69
0.0987
Maximum


0.0136
0.0036
0.758
0.0191
1.69
0.0987
Kp
(cm/hr)

0.001
0.001
0.001
0.001
0.001
0.001
t event
(hr/event)

1
1
1
1
1
1

l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03

event for 1



Conversion
Factor
(l/cm3)

l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03
l.OE-03

1.4E-08 1.4E-08
3.6E-09 3.6E-09
7.6E-07 7.6E-07
1.9E-08 1.9E-08
1.7E-06 1.7E-06
— —

event/day for 36 days

NONCARC I NOGENI C

DAevent
Average RME

0.79
0.79
0.79
0.79
0.79
0.79

per year in a 365


1.1E-08 1.1E-08
2.8E-09 2.8E-09
6.0E-07 6.0E-07
1.5E-08 1.5E-08
1.3E-06 1.3E-06
— —

Slope
Factor
(mg/kg/day) -1

—
1.5E+00
—
—
—
—

day year for 12 years in a 70 year


Care.
Weight of
Evidence

—
A
—
B2
D
D
SUM
lifetime by

CANCER ESTIMATE
Average RME


—
4.3E-09 4.3E-09
—
—
--
— —
4.3E-09 4.3E-09
a 43 kg child =

RISKS TO CHILD TRESPASSERS

Exposure
Factor
(mg/cm2-event) (cm2-event/kg-day)

1.4E-08 1.4E-08
3.6E-09 3.6E-09
7.6E-07 7.6E-07
1.9E-08 1.9E-08
1.7E-06 1.7E-06
—

4.6
4.6
4.6
4.6
4.6
4.6

Exposure Dose
Average RME
(mg/kg/day)

6.3E-08 6.3E-08
1.7E-08 1.7E-08
3.5E-06 3.5E-06
8.8E-08 8.8E-08
7.8E-06 7.8E-06
_

Reference
Dose
(mg/kg/day)

4.4E-04
3.0E-04

Toxicity
Endpoint


Blood
Skin
7.0E-02 Cardiovasc.
—
2.3E-02
2.0E-02
CNS
CNS
Liver

HAZARD INDEX
Average RME


1.6E-04 1.6E-04
5.5E-05 5.5E-05
5.0E-05 5.0E-05
—
3.4E-04 3.4E-04
—
                                                                                                                                                        SUM          0.0006    0.0006

   Exposure Factor = 2000 cm2 skin surface area for contact per  event  for  1  event/day for 36 days per year in a 365 day year by a 43 kg child = 4.6 cm2-event/kg-day

-------
                                                                                                      TABIiE  6
                                                                                                                                                Page 1  of 2
Landfill Area A
                                                                                             DAVIS GSR LANDFILL  SITE
                                                                                       CURRENT LEACHATE SOIL INGESTION PATHWAY
                                                                                       CARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Pesticides/PCBs
PCB Aroclor 1248
   Concentration
Average    Maximum
       (mg/kg)
                                         0.027
                                                     0.045
Exposure Factor
  Ingestion
 (kg/kg/day)
                                                                     2.2E-08
  Exposure Dose
Average      RME
    (mg/kg/day)
                                                                                        5.9E-10    9.9E-10
     Cancer
Slope Factor
  (mg/kg/day)-1
                                                                                                              7.7E+00
 Weight
   of
Evidence
                                                                                                                                B2
  RISK ESTIMATE
Average      RME
                                                                                                                                           4.6E-09     7.6E-09
Inorganics
Antimony
Arsenic
Barium
Beryllium
Manganese
Vanadium
Zinc
2.5
1.8
137
0.38
447
8
72
2.5
7
293
0.61
1680
12.4
165
7
7
7
7
7
7
7
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
1.
1.
9.
2.
3.
5.
5.
8E-07
3E-07
9E-06
7E-08
2E-05
8E-07
2E-06
1,
5,
2,
4,
1,
8,
1,
. 8E-07
. OE-07
. IE-OS
. 4E-08
.2E-04
. 9E-07
.2E-05
—
1.5E+00
—
4.3E+00
—
—
--
                                                                                       A

                                                                                       B2
                                                                                       D
                                                                                       D
                                                                                       D
                                                                        1.9E-07    7.6E-07

                                                                        1.2E-07    1.9E-07
                                                                                                                                SUM        3.2E-07
Exposure Factor:
  Ingestion - 200 mg of leachate soil ingested per day with 100% absorption for Inorganics and 30% for PCBs  for  36 days
  in a 365 day year for 12 years in a 70 year lifetime by a 43 kg child and a conversion factor of kg/10+6 mg=7.2 x  10-8  kg  of  soil  per  kg  body
  weight per day and 2.2 x 10-8 kg soil per kg body weight per day for PCBs.
                                                                                                                                                     9.5E-07

-------
                                                                                             TABIiE  6  (cont'd)
                                                                                                      Page  2 of  2
Landfill Area A
                                                                                         DAVIS GSR LANDFILL  SITE
                                                                                 CURRENT LEACHATE SOIL  INGESTION PATHWAY
                                                                                NONCARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Pesticides/PCBs
PCB Aroclor 1248
   Concentration
Average    Maximum
       (mg/kg)
                                         0.027
                                                    0.045
Exposure Factor
  Ingestion
 (kg/kg/day)
                                                                      1.7E-07
  Exposure Dose
Average     RME
    (mg/kg/day)
                                                                                        4.6E-09
                                                                                                  7.7E-09
 Reference
  Dose
(mg/kg/day)
Toxicity
Endpoint
  HAZARD INDEX
Average     RME
Inorganics
Antimony
Arsenic
Barium
Beryllium
Manganese
Vanadium
Zinc
2.5
1.8
137
0.38
447
8
72
2.5
7
293
0.61
1680
12.4
165
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
1.
8.
6.
1.
2.
3.
3.
2E-06
5E-07
4E-05
8E-07
1E-04
8E-06
4E-05
1,
3,
1,
2,
7,
5,
7,
.2E-06
.3E-06
. 4E-02
. 9E-07
. 9E-04
.8E-06
. 8E-05
4,
3,
7,
5,
2,
7,
3,
. OE-04
. OE-04
. OE-02
. OE-03
.3E-02
.OE-03
. OE-01
Blood
Skin
Cardiovasc.
None
CNS
Liver
Blood
2
2
9
3
9
5
1
.9E-03
.8E-03
.2E-04
. 6E-05
.1E-03
.4E-04
.1E-04
2
1
2
5
3
8
2
.9E-03
.1E-02
.OE-03
.7E-05
.4E-02
.3E-04
.6E-04
                                                                                                                                  SUM
Exposure Factor:
  Ingestion - 200 mg of soil ingested per day with 100% absorption for Inorganics and 305 for PCBs  for  36 days
  in a 365 day for 12 years by a 43 kg child and a conversion factor of kg/10+6 mg = 4.7 x  10-7  kg  of soil per  kg body weight per day
  and 1.4 x 10-7 kg soil per kg body weight per day for PCBs.
                                                                                                                                              0.016
                                                                                                                                                        0.051

-------
                                                                                                        TABIiE 7
                                                                                                DAVIS GSR LANDFILL SITE
                                                                                     CURRENT LEACHATE SOIL DERMAL CONTACT PATHWAY

                                                                                        CARCINOGENIC RISKS TO CHILD TRESPASSER
Landfill Area A
Contaminants of
Concern

Pesticides/PCBs
PCB Aroclor 1248
    Concentration      Adherence   Absorption  Conversion        DAevent        Exposure         Exposure Dose
Average     Maximum     Factor      Factor      Factor     Average   Maximum     Factor         Average     RME
        (mg/kg)        (mg/cm2-event)              (kg/mg)       (mg/cm2-event)  (cm2-event/kg/day)     (mg/kg/day)
                    0.027
                                 0.045
                                             0.5
                                                         0.06
                                                                    l.OE-06
                                                                                i.lE-10   1.4E-09   7.9E-01
                                                                                                                    6.4E-10    1.1E-09
     Cancer
  Slope  Factor
(mg/kg/day) -1
                                                                                                                                           7.7E+00
 Weight
   of
Evidence
  RISK ESTIMATE
Average      RME
                                                                                                                                                           B2        4.9E-09    8.2E-09

                                                                                                                                                           SUM      4.9E-09    8.2E-09
Exposure Factor = 2000 cm2 skin surface area for contact per event for 1 event/day for 36 days per
year in a 365 day year for 12 years in a 70 year lifetime by a 43 kg child = 0.79 cm2-event/kg-day.
Landfill Area A
                                                                                      NONCARCINOGENIC RISKS TO CHILD TRESPASSER
                        Concentration      Adherence   Absorption  Conversion        DAevent        Exposure         Exposure Dose     Reference     Toxicity     HAZARD  INDEX
Contaminants of     Average     Maximum     Factor      Factor      Factor       Average  Maximum    Factor         Average     RME      Dose        Endpoint   Average     RME
Concern                    (mg/kg)        (mg/cm2-event)              (kg/mg)         (mg/cm2-event)  (cm2-event/kg/day)    (mg/kg/day)      (mg/kg/day)
Pesticides/PCBs
PCB Arcolor 1248    0.027
                                 0.045
                                              0.5
                                                         0.06
                                                                   l.OE-06
                                                                                i.lE-10  1.4E-09    4.6E+00
                                                                                                                   3.7E-09    6.2E-09
                                                                                                                                                      SUM
Exposure Factor = 2000 cm2 skin surface area for contact per event for 1 event/day for 36 days per year in a 365 day year by a  43  kg child  =4.6  cm2-event/kg-day.

-------
                                                    TABIiE 8
                                                                                                                                                Page 1  of 6
Landfill Area A
                                             DAVIS GSR LANDFILL SITE
                                    CURRENT SURFICIAL SOIL INGESTION PATHWAY
                                     CARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Semi-Volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Pesticides/PCBs
PCBs(total)
      Concentration      Exposure Factor
   Average     Maximum      Ingestion
         (mg/kg)            (kg/kg/day)
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
7,
7,
7,
7,
7,
7,
7,
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
 Exposure Dose
Average       RME
     (mg/kg/day)
   Cancer        Weight
Slope Factor        of
 (mg/kg/day)-1  Evidence
0.015
              0.015
                           2.2E-08
                                            3.3E-10
                                                        3.3E-10
                                                                        7.3E+00
                                                                        7.3E+00
                                                                        7.3E+00
                                                                        7.3E+00
                                                                        7.3E+00
                                                                        7.3E+00
                                                                        7.3E+00
                                                                        7.7E+00
                                        B2
                                        B2
                                        B2
                                        B2
                                        B2
                                        B2
                                        B2
                                                                                       B2
 RISK ESTIMATE
Average       RME
                                                                                                   2.5E-09
                                                                                                               2.5E-09
Inorganics
Arsenic
Barium
Beryllium
Cadmium
Manganese
Mercury
Nickel
Thallium
Vanadium
Zinc
ND
30
0.29
ND
124
0.089
3.2
ND
6.5
101
ND
45.8
0.5
ND
172
0.19
7.8
ND
11.3
318
7,
7,
7,
7,
7,
7,
7,
7,
7,
7,
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08

2,
2,

8,
6,
2,

4,
7,
—
.2E-06
. IE-OS
—
. 9E-06
. 4E-09
.3E-07
—
. 7E-07
.3E-06

3,
3,

1.
1.
5,

8,
2,
—
.3E-06
. 6E-08
—
.2E-05
.4E-08
. 6E-07
—
. 1E-07
.3E-05
1.5E+00 A
—
4.3E+00 B2
—
D
D
A(inh.
D
D
D
                                                                                                   9.0E-C
                                                                                                               1.5E-07
                                                                                                                              SUM
                                                                                                                                          9.2E-C
                                                                                                                                                     1.6E-07
Exposure Factor:
 Ingestion - 200 mg of soil ingested per day with 100% absorption for SVOCs and Inorganics and 30% for PCBs  for  36  days
 in a 365 day year for 12 years in a 70 year lifetime by a 43 kg child and a conversion factor of kg/10+6 mg=  7.2 x 10-8  kg  of  soil/kg bw/day for  SVOCs  and Inorganic
 and 2.2x10-8 kg of soil/kg bw/day for PCBs.

-------
                                                     TABIiE 8  (cont'd.)
                                                                                 Page 2 of 6
Landfill Area A
                                                DAVIS GSR LANDFILL SITE
                                       CURRENT SURFICIAL SOIL INGESTION PATHWAY
                                       NONCARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Semi-Volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Pesticides/PCBs
PCBs  (total)

Inorganics
Arsenic
Barium
Beryllium
Cadmium
Manganese
Mercury
Nickel
Thallium
Vanadium
Zinc
     Concentration      Exposure Factor
  Average     Maximum      Ingestion
        (mg/kg)            (kg/kg/day)
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
4,
4,
4,
4,
4,
4,
4,
. 7E-07
.7E-07
. 7E-07
. 7E-07
.7E-07
. 7E-07
.7E-07
0.015
 ND
30
0.29
 ND
124
0.089
3.2
 ND
6.5
101
            0.015
  ND
45.8
0.5
  ND
172
0.19
7.8
 ND
11.3
318
                          1.4E-07
                                   Exposure Dose
                                  Average       RME
                                      (mg/kg/day)
                                         2.1E-09
                                                        2.1E-09
 Reference
  Dose
(mg/kg/day)
Toxicity
 Endpoint
  HAZARD INDEX
Average       RME
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07

1.
1.

5,
4,
1.

3,
4,
—
. 4E-05
. 4E-07
--
. 8E-05
.2E-08
.5E-06
—
. 1E-06
.7E-05

2,
2,

8,
8,
3,

5,
1.
—
.2E-05
. 4E-07
--
. IE-OS
. 9E-08
.7E-07
—
.3E-06
.5E-04
3.
7.
5.
1.
2.
3.
2.
8.
7.
3.
, OE-04
, OE-02
, OE-03
, OE-03
,3E-02
, OE-04
, OE-02
, OE-05
, OE-03
. OE-01
Skin
Cardiovasc.
None
Kidney
CNS
CNS
Organ Wt
Liver
Liver
Blood

2
2

2
1
7

4
1
—
.OE-04
.7E-05
--
.5E-03
.4E-04
.5E-05
—
.4E-04
.6E-04

3
4

3
3
1

7
5
—
.1E-04
.7E-05
--
.5E-03
.OE-04
.8E-04
—
.6E-04
.OE-04
                                                                                                                              SUM
                                                                                                                                          0.0034
                                                                                                                                                      0.0051
Exposure Factor:
 Ingestion - 200 mg of soil ingested per day with 100% absorption for SVOCs and Inorganics and 30% for PCBs  for  36 days
 in a 365 day by a 43 kg child and a conversion factor of kg/10+6 mg = 4.7 x 10-7 kg of soil/kg bw/day for SVOCs  and  Inorganics
 and 1.4x10-7 kg of soil/kg bw/day for PCBs.

-------
                                                    TABIiE 8  (cont'd)
                                                                           Page 3 of 6
Landfill Area B
                                                DAVIS GSR LANDFILL SITE
                                      CURRENT SURFICIAL SOIL INGESTION PATHWAY
                                       CARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Semi-Volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Pesticides/PCBs
PCBs  (total)

Inorganics
Arsenic
Barium
Beryllium
Cadmium
Manganese
Mercury
Nickel
Thallium
Vanadium
Zinc
      Concentration      Exposure Factor
   Average     Maximum      Ingestion
         (mg/kg)            (kg/kg/day)
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
7,
7,
7,
7,
7,
7,
7,
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
0.042
               0.052
                            2.2E-08
 Exposure Dose
Average       RME
     (mg/kg/day)
   Cancer        Weight
Slope Factor        of
 (mg/kg/day)-1  Evidence
                                            9.2E-10
                                                          1.1E-09
                                                                         7.3E+00
                                                                         7.3E+00
                                                                         7.3E+00
                                                                         7.3E+00
                                                                         7.3E+00
                                                                         7.3E+00
                                                                         7.3E+00
                                                                         7.7E+00
                                         B2
                                         B2
                                         B2
                                         B2
                                         B2
                                         B2
                                         B2
                                                                                        B2
ND
57
0.18
ND
217
0.055
6.9
ND
8.6
81
ND
57.6
0.2
ND
282
0.065
10.9
ND
9.6
118
7,
7,
7,
7,
7,
7,
7,
7,
7,
7,
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08

4,
1.

1.
4,
5,

6,
5,
—
. 1E-06
.3E-08
—
. 6E-05
. OE-09
. OE-07
—
.2E-07
.8E-06

4,
1.

2,
4,
7,

6,
8,
—
. 1E-06
. 4E-08
—
. OE-05
.7E-09
. 8E-07
—
. 9E-07
.5E-06
1.5E+00 A
—
4.3E+00 B2
—
D
D
A (inn
D
D
D
 RISK ESTIMATE
Average       RME
                                                                                                   7.1E-09
                                                                                                                  i.SE-09
                                                                                                   5.6E-C
                                                                                                                 6.2E-08
                                                                                                                              SUM
                                                                                                                                          6.3E-C
                                                                                                                                                       7.1E-08
Exposure Factor:
 Ingestion - 200 mg of soil ingested per day with 100% absorption for SVOCs and Inorganics and 30% for PCBs  for  36 days
 in a 365 day year for 12 years in a 70 year lifetime by a 43 kg child and a conversion factor of kg/10+6 mg= 7.2 x  10-8  kg  of  soil/kg bw/day  for  SVOCs  and Inorganic
 and 2.2x10-8 kg of soil/kg bw/day for PCBs.

-------
                                                                  Table 8  (cont'd)
                                                                                            Page 4 of 6
Landfill Area B
                                                            DAVIS GSR LANDFILL SITE
                                                     CURRENT SURFICIAL SOIL INGESTION PATHWAY
                                                    NONCARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
   Concentration    Exposure Factor
Average    Maximum     Ingestion
       (mg/Kg)          (kg/kg/day)
Semi-volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Pesticides/PCBs
PCBs  (total)
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
4
4
4
4
4
4
4
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
.7E-07
 0.042
            0.052
                       1.4E-07
                           Exposure Dose
                         Average      RME
                            (mg/kg/day)
                                      5.9E-09
                                                 7.3E-09
                                    Reference
                                       Dose
                                   (mg/kg/day)
 Toxicity
Endpoint
 HAZARD INDEX
Average      RME
Inorganics
Arsenic
Barium
Beryllium
Cadmium
Manganese
Mercury
Nickel
Thallium
Vanadium
Zinc
   ND
   57
  0.18
   ND
  217
 0.055
  6.9
   ND
  8.6
   81
 ND
57.6
 0.2
 ND
 282
0.065
10.9
 ND
 9.6
 118
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07
4.7E-07

2
8

1
2
3

4
3
—
.7E-05
.5E-08
--
.OE-04
.6E-08
.2E-06
—
.OE-06
.8E-05

2,
9,

1.
3,
5,

4,
5,
—
.7E-05
. 4E-08
--
.3E-04
. IE-OS
. 1E-06
—
.5E-06
.5E-05
3
7
5
1
2
3
2
8
7
3
.OE-04
.OE-02
.OE-03
.OE-03
.3E-02
.OE-04
.OE-02
.OE-05
.OE-03
.OE-01
Skin
Cardiovasc.
None
Kidney
CNS
CNS
Organ Wt
Liver
Liver
Blood

3.
1.

4.
8.
1.

5.
1.
—
8E-04
7E-05
-
4E-03
6E-05
6E-04
—
8E-04
3E-04

3.
1.

5.
1.
2.

6.
1.
—
, 9E-04
, 9E-05
--
, 8E-03
, OE-04
, 6E-04
—
, 4E-04
, 8E-04
                                                                                                           SUM      0.0057     0.0072
Exposure Factor
  Ingestion - 200 mg of soil ingested per day with 100% absorption for SVOCs and Inorganics and 30% for PCBs for 36 days
  in a 365 day by a 43 kg child and a conversion factor of kg/10+6 mg = 4.7 x 10-7 kg of soil/kg bw/day for SVOCs and Inorganics
  and 14x10-7 kg of soil/kg bw/day for PCBs.

-------
                                                                  TABIiE 8  (cont'd)
                                                                                            Page 5 of 6
Off-Landfill
                                                              DAVIS GSR LANDFILL SITE
                                                     CURRENT SURFICIAL SOIL INGESTION PATHWAY
                                                      CARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
Semi-Volatile Organic Compounds
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-d)pyrene)
Total Carcinogenic PAHs

Pesticides/PCBs
PCBs  (total)
Concentration Exposure Factor Exposure Dose
Average Maximum Ingestion Average RME
(mg/kg)
0.076
0.064
0.086
0.063
0.074
0.22
0.58
0.076
0.064
0.086
0.063
0.074
0.27
0.63
(kg/kg/day)
7
7
7
7
7
7
7
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
5.
4.
6.
4.
5.
1.
4.
(mg/kg/day)
5E-09
6E-09
2E-09
5E-09
3E-09
6E-08
2E-08
5,
4,
6,
4,
5,
1.
4,
.5E-09
. 6E-09
.2E-09
.5E-09
.3E-09
. 9E-08
. 6E-08
Cancer
Slope Factor
(mg/kg/day)
7.3E+00
7.3E+00
7.3E+00
7.3E+00
7.3E+00
7.3E+00
7.3E+00
Weight
of
Evidence
B2
B2
B2
B2
B2
B2
B2
RISK ESTIMATE
Average RME

4.0E-08
3.4E-08
4.5E-08
3.3E-08
3.9E-08
1.2E-07
3.1E-07

4.0E-08
3.4E-08
4.5E-08
3.3E-08
3.9E-08
1.4E-07
3.3E-07
0.073
            0.31
                       2.2E-C
                                     1.6E-09
                                                6.8E-09
                                                           7.7E+00
                                                                           B2
                                                                                    1.2E-08
                                                                                               5.3E-C
Inorganics
Arsenic
Barium
Beryllium
Cadmium
Manganese
Mercury
Nickel
Thallium
Vanadium
Zinc


0
0

0

0


1.9
43
.42
.35
359
.11
3.5
.17
13
179
3.9
55.7
0.85
0.79
656
0.18
7.3
0.36
21.8
800
7
7
7
7
7
7
7
7
7
7
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
.2E-08
1.
3.
3.
2.
2.
7.
2.
1.
9.
1.
4E-07
1E-06
OE-08
5E-08
6E-05
9E-09
5E-07
2E-08
4E-07
3E-05
2,
4,
6,
5,
4,
1,
5,
2,
1,
5,
.8E-07 1.5E+00
. OE-06
. 1E-08 4.3E+00
.7E-08
.7E-05
.3E-08
.3E-07
. 6E-08
. 6E-06
. 8E-05
A
—
B2
—
D
D
A(inh)
D
D
D
2.1E-07 4.2E-07
—
1.3E-07 2.6E-07
-
_
-
--
-
-
- -
                                                                                                           SUM         6.5E-07     1.1E-06
Exposure Factor:
  Ingestion - 200 mg of soil ingested per day with 100% absorption for SVOCs and Inorganics and 30%  for PCBs for  36  days
  in a 365 day year for 12 years in a 70 year lifetime by a 43 kg child and a conversion factor of kg/10+6=7.2 x  10-8  of  soil/kg bw/day  for  SVOCs  and Inorganic
  and 2.2x10-8 kg of soil/kg bw/day for PCBs

-------
                                                                  Table 8  (cont'd)
                                                                                            Page 6 of 6
Off-Landfill
                                                              DAVIS GSR LANDFILL SITE
                                                      CURRENT SURFICIAL SOIL INGESTION PATHWAY
                                                      NONCARCINOGENIC RISKS TO CHILD TRESPASSER
Contaminants of Concern
   Concentration    Exposure Factor
Average    Maximum     Ingestion
       (mg/Kg)          (kg/kg/day)
Semi-Volatile Organic Compounds
Benzo(a)anthracene              0.76       0.76
Benzo(a)pyrene                 0.064      0.064
Benzo(b)fluoranthene           0.086      0.086
Benzo(k)fluoranthene           0.063      0.063
Chrysene                       0.074      0.074
Indeno(l,2,3-d)pyrene)          0.22       0.27
Total Carcinogenic PAHs         0.58       0.63

Pesticides/PCBs
PCBs  (total)                   0.073       0.31

Inorganics
Arsenic                          1.9        3.9
Barium                            43       55.7
Beryllium                       0.42       0.85
Cadmium                         0.35       0.79
Manganese                        359        656
Mercury                         0.11       0.18
Nickel                           3.5        7.3
Thallium                        0.17       0.36
Vanadium                          13       21.8
Zinc                             179        800
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        1.4E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
                        4.7E-07
Exposure Dose
Average RME
(mg/kg/day)
3.6E-08 3.6E-08
3.0E-08 3.0E-08
4.0E-08 4.0E-08
3.0E-08 3.0E-08
3.5E-08 3.5E-08
l.OE-07 1.3E-07
2.7E-07 3.0E-07
1.
8.
2.
2.
1.
1.
5.
1.
8.
6.
8.
OE-08
9E-07
OE-05
OE-07
6E-07
7E-04
2E-08
6E-06
OE-08
1E-06
4E-05
4,
1,
2,
4,
3,
3,
8,
3,
1,
1,
3,
.3E-08
.8E-06
. 6E-05
.OE-07
.7E-07
. 1E-04
.5E-08
.4E-06
. 7E-07
.OE-05
. 8E-04
Reference
Dose
(mg/kg/day)

3
7
5
1
2
3
2
8
7
3
--
.OE-04
.OE-02
.OE-03
.OE-03
.3E-02
.OE-04
.OE-02
.OE-05
.OE-03
.OE-01
Toxicity
Endpoint
--
Skin
Cardiovasc
None
Kidney
CNS
CNS
Organ Wt
Liver
Liver
Blood
HAZARD INDEX
Average RME

3.
2.
3.
1.
7.
1.
8.
1.
8.
2.
-
OE-03
9E-04
9E-05
6E-04
3E-03
7E-04
2E-05
OE-03
7E-04
8E-04

6,
3,
8,
3,
1,
2,
1,
2,
1,
1,
--
. 1E-03
.7E-04
.OE-05
.7E-04
. 3E-02
. 8E-04
.7E-04
. 1E-03
.5E-03
. 3E-03
                                                                                                           SUM        0.013      0.024
Exposure Factor:
  Ingestion - 200 mg of soil ingested per day with 100% absorption for SVOCs and Inorganics and 30% for PCBs for 36 days
  in a 365 day by a 43 kg child and a conversion factor of kg/10+6 mg = 47 x 10-7 kg of soil/kg bw/day for SVOCs and Inorganics
  and 1.4x10-7 kg of soil/kg bw/day for PCBs

-------
                                                                  TABIiE 9
                                                                                                                              Page 1 of 3
                                                          DAVIS GSR LANDFILL SITE
                                               CURRENT SURFICIAL SOIL DERMAL CONTACT PATHWAY

                                                  CARCINOGENIC RISKS TO CHILD TRESPASSER
Landfill Area A
Contaminants
of Concern
                  Concentration      Adherence    Absorption    Conversion
               Average    Maximum      Factor       Factor
                      (mg/kg)       (mg/cm2-event)
Pesticides/PCBs
PCB Aroclor 1248  0.015    0.015
Inorganics
Cadmium
                   ND
                             ND
                                         0.5
                                         0.5
                                                     0.06
                                                     0.01
               DAevent
Factor    Average   Maximum
                                                                                 Exposure         Exposure Dose         Cancer
                                                                                  Factor        Average       RME    Slope Factor
                                                                  (kg/mg)
            (mg/cm2-event)    (cm2-event/kg-day)      (mg/kg/day)
                                                                 l.OE-06    4.5E-10   4.5E-10
                                                                 l.OE-06
                                                                                                     7.9E-01
                                                                                                      7.9E-01
                                                                                                                   3.6E-10   3.6E-10
                                                                                                                                           7.7E+00
Weight    RISK ESTIMATE
  of     Average     RME
                                                                                                                     (mg/kg/day)-1    Evidence
                                                                                                                                                           B2


                                                                                                                                                       Bl(inh.;

                                                                                                                                                          SUM
                                                                                                                                                                  2.7E-09  2.7E-09
                                                                                                                                                                  2.7E-09  2.7E-09
Exposure Factor = 2000 cm2 skin surface area for contact per event for 1 event/day for 36 days per year in a 365 day year for 12 years in a 70 year lifetime by a 43 kg child =  0.79
cm2-event/kg-day
                                                  NONCARCINOGENIC RISKS TO CHILD TRESPASSER
Landfill Area A

Contaminants
of Concern
                                                                                                                Exposure Dose     Reference   Toxicity
Pesticides/PCBs
PCB Aroclor 1248    0.015    0.015
Inorganics
Cadmium
                      ND
                               ND
                                          0.5
                                          0.5
                                                     0.06
                                                     0.01
                                                                 l.OE-06   4.5E-10   4.5E-10      4.6E+00
                                                                 l.OE-06      --        --         4.6E+00
                                                                                                               2.1E-09  2.1E-09
                                                                                                                                   l.OE-3
                                                                                          HAZARD INDEX
  Concentration    Adherence    Absorption  Conversion       DAevent          Exposure
Average  Maximum     Factor       Factor      Factor    Average   Maximum       Factor      Average     RME       Dose     Endpoint     Average    RME
      (mg/kg)      (mg/cm2-event)               (kg/mg)      (mg/cm2-event)   (cm2-event/kg-day)    (mg/kg/day)     (mg/kg/day)
                                                                                                                                               Kidney

                                                                                                                                                 SUM

Exposure Factor = 1000 cm2 skin surface area for contact per event/day for 1 event/day for 36 days per year in a 365 day year by a 43 kg child = 4.6 cm2-event/kg-day

-------
                                                                  TABIiE 9
                                                                                                                                                           Page 2 of 3
                                                         DAVIS GSR LANDFILL SITE
                                               CURRENT SURFICIAL SOIL DERMAL CONTACT PATHWAY

                                                   CARCINOGENIC RISKS TO CHILD TRESPASSER

Landfill Area B

Contaminants       Concentration      Adherence    Absorption    Conversion       DAevent            Exposure         Exposure Dose         Cancer
of Concern      Average    Maximum      Factor       Factor        Factor    Average   Maximum        Factor        Average       RME    Slope Factor
                      (mg/kg)        (mg/cm2-event)
                                                                   (kg/mg)
(mg/cm2-event)    (cm2-event/kg-day)      (mg/kg/day)
Pesticides/PCBs
PCB Aroclor 1248  0.042
                            0.062         0.5          0.6
Inorganics
Cadmium
                   ND         ND          0.5         0.01
                                                                  l.OE-06    1.3E-09   1.6E-09
                                                                  l.OE-06
                                                                                                     7.9E-01
                                                                                                      7.9E-01
                                                                                                                    l.OE-09    1.2E-09
                                                                                                                                            7.7E+00
                                                                                                                                                          Weight    RISK ESTIMATE
                                                                                                                                                            of     Average     RME
                                                                                                                      (mg/kg/day)-1    Evidence
                                                                                                                                                            B2
                                                                                                                                                                   7.7E-09   9.5E-09
                                                                                                                                                        Bl  (inh.)

                                                                                                                                                            SUM    7.7E-09   9.5E-09
Exposure Factor = 2000 cm2 skin surface area for contact per event for 1 event/day for 36 days per year in a 365 day year for 12 years in a 70 year lifetime by a  43  kg child =  0.79
cm2-event/kg-day
                                                   NONCARCINOGENIC RISKS TO CHILD TRESPASSER
Landfill Area B

Contaminants
of Concern
                                                                                                                Exposure Dose     Reference   Toxicity
Pesticides/PCBs
PCB Aroclor 1248    0.042    0.052
Inorganics
Cadmium
                      ND
                               ND
                                         0.5
                                         0.5
                                                       0.6
                                                      0.01
                                                                 l.OE-06   1.3E-09   1.6E-09      4.6E+00
                                                                 l.OE-06      --       --         4.6E+00
                                                                                                               5.8E-09  7.2E-09
                                                                             HAZARD INDEX
  Concentration    Adherence    Absorption  Conversion       DAevent          Exposure
Average  Maximum     Factor       Factor      Factor    Average   Maximum       Factor      Average     RME       Dose     Endpoint     Average    RME
      (mg/kg)      (mg/cm2-event)                (kg/mg)      (mg/cm2-event)   (cm2-event/kg-day)    (mg/kg/day)     (mg/kg/day)
                                                                                                                                   l.OE-03     Kidney

                                                                                                                                                 SUM

Exposure Factor = 2000 cm2 skin surface area for contact per event for 1 event/day for 36 days per year in a 365 day year by a 43 kg child =4.6 cm2-event/kg-day

-------
                                                                  TABIiE 9
                                                                                                                                                                   Page  3 of  3
                                                         DAVIS GSR LANDFILL SITE
                                              CURRENT SURFICIAL SOIL DERMAL CONTACT PATHWAY

                                                  CARCINOGENIC RISKS TO CHILD TRESPASSER

Off-Landfill

Contaminants       Concentration      Adherence    Absorption    Conversion       DAevent            Exposure         Exposure Dose         Cancer        Weight    RISK ESTIMATE
of Concern      Average    Maximum      Factor       Factor        Factor    Average   Maximum        Factor        Average       RME    Slope Factor       of     Average     RME
                      (mg/kg)
                                     (mg/cm2-event)
(kg/mg)       (mg/cm2-event)    (cm2-event/kg-day)      (mg/kg/day)       (mg/kg/day)-1    Evidence
Pesticides/PCBs
PCB Aroclor 1248  0.073
Inorganics
Cadmium
                   ND
                             0.31        0.5          0.06
                              ND          0.5         0.01
                                                                  l.OE-06    2.2E-09   9.3E-09
                                                                  l.OE-06
                                                                                                     7.9E-01
                                                                                                      7.9E-01
                                                                                                                    1.7E-09    7.3E-09
                                                                                                                                            7.7E+00         B2      1.3E-08   5.7E-C


                                                                                                                                                        Bl  (inh.)

                                                                                                                                                            SUM     1.3E-08   5.7E-C
Exposure Factor = 2000 cm2 skin surface area for contact per event for 1 event/day for 36 days per year in a 365 day year for 12 years in a 70 year lifetime by a  43  kg  child =  0.79
cm2-event/kg-day
                                                   NONCARCINOGENIC RISKS TO CHILD TRESPASSER

Off-Landfill

Contaminants         Concentration    Adherence    Absorption  Conversion       DAevent          Exposure       Exposure Dose     Reference   Toxicity      HAZARD  INDEX
of Concern         Average  Maximum     Factor       Factor      Factor    Average   Maximum       Factor      Average     RME       Dose     Endpoint     Average    RME
                        (mg/kg)      (mg/cm2-event)               (kg/mg)      (mg/cm2-event)   (cm2-event/kg-day)    (mg/kg/day)     (mg/kg/day)
Pesticides/PCBs
PCB Aroclor 1248    0.073     0.31
Inorganics
Cadmium
                     0.35     0.79
                                         0.5
                                         0.5
                                                       0.06      l.OE-06   2.2E-09   9.3E-09      4.6E+00
                                                       0.01      l.OE-06   1.8E-09   4.0E-09      4.6E+00
                                                                                                               l.OE-08  4.3E-C
                                                                                                               8.1E-09  1.8E-08    l.OE-03     Kidney       8.1E-06   1.8E-05

                                                                                                                                                 SUM       0.0000081

Exposure Factor = 2000 cm2 skin surface area for contact per event for 1 event/day for 36 days per year in a 365 day year by a 43 kg child =4.6 cm2-event/kg-day

-------
                                                                  TABIiE 10
                                                          DAVIS GSR LANDFILL SITE
                                                   FUTURE BORING SOIL INGESTION PATHWAY
                                                                                             Page 1 of 2
Off-Landfill
                                                    CARCINOGENIC RISKS TO ADULT WORKER
Contaminants of Concern
   Concentration
Average     Maximum
       (mg/kg)
Exposure Factor
   Ingestion
  (kg/kg/day)
  Exposure Dose
Average       RME
    (mg/kg/day)
   Cancer       Weight
Slope  Factor    of
(mg/kg/day)-1  Evidence
   RISK ESTIMATE
Average        RME
SVOCs
Bis (2-ethylhexyl)phthalate
Noncarcinogenic PAHs
Fluoranthene
Fluorene
Phenanthrene
Pyrene
Carcinogenic PAHs
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-cd)pyrene
TOTAL cPAHs

Pesticides/PCBs
Dieldrin
PCB Aroclor 1248

Inorganics
Antimony
Arsenic
Barium
Manganese
Nickel
Selenium
Silver
Vanadium
Zinc
  0.32
              0.32
                          6.9E-09
                                       2.2E-09   2.2E-09
                                                               1.40E-02
                                                                              B2
                                                                                      3.1E-11    3.1E-11
ND
ND
ND
ND
0.2
0.33
0.2
0.2
0.2
0.2
1.3
0.22
1.6
2.7
2.1
26
100
1.9
1.5
ND
5.8
27
ND
ND
ND
ND
0.22
1.7
0.22
0.22
0.22
0.22
2.8
0.22
1.6

8.7
87.6
214
4.2
12.5
ND
16.5
53.4
6.
6.
6.
6.
6.
6.
6.
6.
6.
6.

2.
2.
6.
6.
6.
6.
6.
6.
6.
6.
6.
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09

1E-09
1E-09
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09
9E-09


1.
2,
1.
1.
1.
1.
9,
4,
3,
1.
1.
1.
6,
1.
1.

4,
1.
--
—
.4E-09
.3E-09
.4E-09
.4E-09
.4E-09
.4E-09
.2E-09
. 6E-10
.4E-09
.9E-08
.4E-08
.8E-07
. 9E-07
.3E-08
.OE-08
—
.OE-08
.9E-07


1.
1.
1.
1.
1.
1.
1.
4,
3,
3,
6,
6,
1.
2,
8,

1.
3,
--
—
.5E-09
.2E-08
.5E-09
.5E-09
.5E-09
.5E-09
. 9E-08
. 6E-10
.4E-09
.7E-08
.OE-08
. OE-07
.5E-06
. 9E-08
. 6E-08
—
. 1E-07
.7E-07
--
—
7.3E+00
7.3E+00
7.3E+00
7.3E+00
7.3E+00
7.3E+00

1.6E+01
7.7E+00

1.5E+00
—
—
—
—
—
—
--
D
D
D
D
B2
B2
B2
B2
B2
B2

B2
B2

A
—
D
A (inh)
D
D
D
D


1.
1.
1.
1.
1.
1.
6,
7,
2,

2,







--
—
.OE-08
.7E-08
.OE-08
.OE-08
.OE-08
.OE-08
.7E-08
. 4E-09
. 6E-08

.2E-08
—
-
-
-
—
-
-
--
—
1.1E-08
8.6E-08
1.1E-08
1.1E-08
1.1E-08
1.1E-08
1.4E-07
7.4E-09
2.6E-08

9. OE-08
—
—
—
—
—
—
-
                                                                                                          SUM      1.2E-07    2.6E-07
Exposure Factor:
  Ingestion - 50 mg of leachate soil ingested per day with 100% absorption for SVOCs and Inorganics and 30% for Pesticides/PCBs for 250 days
  in a 365 day year for 1 year in a 70 year lifetime by a 70 kg adult and a conversion factor of kg/10+6 mg=6.9 x 10.9 kg of soil per kg body weight per day for SVOC
  and Inorganics and 2.1 x 10-9 kg of soil per kg body weight per day for Pesticides/PCBs

-------
                                                                  TABIiE 10  (cont'd)
                                                              DAVIS GSR LANDFILL SITE
                                                       FUTURE BORING SOIL INGESTION PATHWAY
                                                                                               Page 2 of 2
Off-Landfill
                                                       NONCARCINOGENIC RISKS TO ADULT WORKER
                              Concentration
Contaminants of Concern    Average     Maximum
                                  (mg/kg)
SVOCs
Bis (2-ethylhexyl)phthalate
Noncarcinogenic PAHs
Fluoranthene
Fluorene
Phenanthrene
Pyrene
Carcinogenic PAHs
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Chrysene
Indeno(1,2,3-cd)pyrene
TOTAL PAHs

Pesticides/PCBs
Dieldrin
PCB Aroclor 1248

Inorganics
Antimony
Arsenic
Barium
Manganese
Nickel
Selenium
Silver
Vanadium
Zinc
0.32
            0.32
                     Exposure Factor
                        Ingestion
                       (kg/kg/day)
                          4.9E-07
  Exposure Dose
Average      RME
    (mg/kg/day)
                                          1.6E-07   1.6E-07
 Reference
    Dose
(mg/kg/day)
                                                                  2.0E-02
Toxicity      HAZARD INDEX
Endpoint    Average     RME
                                                                                   Liver
                                                                                             7.8E-06   7.8E-06
ND
ND
ND
ND
0.2
0.33
0.2
0.2
0.2
0.2
1.3
0.22
1.6
2.7
2.1
26
100
1.9
1.5
ND
5.8
27
ND
ND
ND
ND
0.22
1.7
0.22
0.22
0.22
0.22
2.8
0.22
1.6
5.4
8.7
87.6
214
4.2
12.5
ND
16.5
53.4
4
4
4
4
4
4
4
4
4
4

1
1
4
4
4
4
4
4
4
4
4
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07

.5E-07
.5E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
.9E-07
9.8E-08
1.6E-07
9.8E-08
9.8E-08
9.8E-08
9.8E-08
6.5E-07
3.3E-08
2.4E-07
1.3E-06
l.OE-06
1.3E-05
4.9E-05
9.3E-07
7.4E-07
—
2.8E-06
1.3E-05
1.
8,
1.
1.
1.
1.
. 1E-07
. 3E-07
. 1E-07
. 1E-07
. 1E-07
. 1E-07
4,
4,
4,
3,
. OE-02
. OE-02
.OE-02
.OE-02
Kidney
Blood
BodyWt .
Kidney
-
--
1.4E-06
3,
2,
2,
4,
4,
1.
2,
6,

8,
2,
.3E-08
. 4E-07
. 6E-06
.3E-06
.3E-05
. OE-04
. 1E-06
. 1E-06
—
. 1E-06
. 6E-05
5,

4,
3,
7,
2,
2,
5,
5,
7,
3,
. OE-05
—
.OE-04
.OE-04
.OE-02
. 3E-02
.OE-02
. OE-03
. OE-03
.OE-03
. OE-01
Liver
—
Blood
Skin
Cardiovasc
CNS
OrganWt
Selenious
Skin
Liver
Blood
6.6E-04
—
3.3E-03
3.4E-03
1.8E-04
2.1E-03
4.7E-05
1.5E-04
-
4.1E-04
4.4E-05
6.6E-04
—
6.6E-03
1.4E-02
6.1E-04
4.6E-03
1. OE-04
1.2E-03
—
1.2E-03
8.7E-05
                                                                                                                   SUM        0.010      0.029
Exposure Factor:
  Ingestion - 50 mg of leachate soil ingested per day with 100% absorption for SVOCs and Inorganics and 30%  for  Pesticides/PCBs  for  250  days
  in a 365 day year by a 70 kg adult and a conversion factor of kg/10+6 mg=4.9 x 10-7 kg of  soil per  kg body weight per day  for  SVOCs  and  Inorganics
  and 1.5 x 10-7 kg of soil per kg body weight per day for Pesticides/PCBs.

-------
                                                                  TABIiE 11

                                                          DAVIS GSR LANDFILL SITE
                                                 FUTURE BORING SOIL DERMAL CONTACT PATHWAY

                                                     CARCINOGENIC RISKS TO ADULT WORKER

Off-Landfill

Contaminants            Concentration      Adherence    Absorption    Conversion       DAevent             Exposure                             Cancer     Weight    RISK ESTIMATE
of Concern           Average    Maximum      Factor       Factor        Factor    Average   Maximum         Factor        Average     RME     Slope Factor    of     Average    RME
                            (mg/kg)        (mg/cm2-event)                 (kg/mg)       (mg/cm2-event)    (cm2-event/kg-day)                    (mg/kg/day)-1  Evidence

Pesticides/PCBs
PCB Aroclor 1248 1.6

Exposure Factor = 2000 cm2
cm2- event /kg-day
1.6 0.5 0.06 l.OE-06 4.8-08 4.8E-08 2.8E-01 1.3E-08 1.3E-08 7.7E+00 B2
SUM
skin surface area for contact per event for 1 event/day for 250 days per year in a 365 day year for 1 year in a 70 year lifetime by a
l.OE-07
l.OE-07
70 kg adult
l.OE-
l.OE-
= 20
                                                     NONCARCINOGENIC RISKS TO ADULT WORKER

Off-Landfill

Contaminants            Concentration      Adherence   Absorption     Conversion       DAevent             Exposure                        Reference     Toxicity    HAZARD INDEX
of Concern           Average    Maximum      Factor      Factor         Factor    Average  Maximum          Factor      Average     RME        Dose       Endpoint   Average     RME
                           (mg/kg)         (mg/cm2-event)                 (kg/mg)      (mg/cm2-event)    (cm2-event/kg-day)                   (mg/kg/day)

Pesticides/PCBs
PCB Aroclor 1248       1.6        1.6          0.5        0.06          l.OE-06    4.8E-08  4.8E-08          2.0E+01     9.6E-07   9.6E-07

                                                                                                                                                          SUM

Exposure Factor = 2000 cm2 skin surface area for contact per event for  1 event/day for 250 days per  year  in a  365 day year  by a  70 kg  adult = 20 cm2  event/kg-day

-------
                                                                  TABIiE 12
                                                          DAVIS GSR LANDFILL SITE
                                                  ON-SITE LANDFILL GAS INHALATION PATHWAY
                                                                                                                     Page 1 of 2
                                                     CARCINOGENIC RISKS TO TRESPASSERS
Contaminants of Concern
Volatile Organic Compounds
Benzene
1,2-Dichloropropane
1,4-Dichlorobenzene
Dichlorodifluoromethane
Ethylbenzene
Methylene Chloride
Tetrachloroethylene
Toluene
1,1,1-Trichloroethane
Trichloroethylene
Vinyl Chloride
   Modeled Concentration
Landfill Area A    Hot Spot
           (mg/m3)
Exposure Factor
     Child
  (m3/kg/day)
4,
3,
8,
3,
5,
2,
4,
2,
3,
3,
3,
.30E-04
. 10E-05
.30E-05
.30E-06
. 10E-04
.30E-06
.50E-06
. 90E-05
. 60E-06
. 60E-06
.40E-06
1.
2,
3,
2,
4,
1.
3,
5,
2,
2,
2,
.70E-05
.30E-05
. OOE-05
.50E-05
. 90E-05
. 80E-05
. 40E-05
.OOE-05
. 80E-05
.70E-05
. OOE-03
6,
6,
6,
6,
6,
6,
6,
6,
6,
6,
6,
.5E-04
.5E-04
.5E-04
.5E-04
.5E-04
.5E-04
.5E-04
.5E-04
.5E-04
.5E-04
.5E-04
       Exposure Dose           Cancer
Landfill Area A    Hot Spot  Slope Factor
        (mg/kg/day)          (mg/kg/day)-1
2,
2,
5,
2,
3,
1.
2,
1.
2,
2,
2,
.8E-07
.OE-09
.4E-08
.1E-09
.3E-07
.5E-09
.9E-09
.9E-08
.3E-09
.3E-09
.2E-09
1.
1.
2,
1.
3,
1.
2,
3,
1.
1.
1.
. IE-OS
.5E-08
. OE-08
. 6E-08
.2E-08
.2E-08
.2E-08
.3E-08
. 8E-08
. 8E-08
.3E-08
2.
9.



1.
2.


6.
3.
, 9E-02
. 1E-02
-
-
—
, 65E-03
, OE-03
—
-
, OE-03
. OE-01
 Weight
   of
Evidence
                                                                                                A
                                                                                               B2
                                                                                               C
                                                                                               D
                                                                                                D
                                                                                               B2
                                                                                               B2
                                                                                                D
                                                                                               D
                                                                                               B2
                                                                                                D

                                                                                               SUM
       RISK ESTIMATE
Landfill Area A    Hot Spot
    Child            Child
                                                                            8.1E-09
                                                                            1.8E-10
                                                                           3.2E-10
                                                                           1.4E-09
2.5E-12
5.9E-12
1.4E-11
6.6E-10
1.9E-11
4.4E-11
1.1E-10
3.9E-07
                                                                                                                                          9.OE-09
                                                                                                                                                          3.9E-07
Exposure Factor
  Inhalation - 0.83 m3 of air inhaled per hour for 2 hours per day of exposure for 36 days of exposure in  a  365 day  year  for  12  years  in  a  70  year  lifetime  by a 43  kg child
  6.5x10-4 m3/kg/da

-------
                                                                 TABLE 12
                                                          DAVIS GSR LANDFILL SITE
                                                 ON-SITE LANDFILL GAS INHALATION PATHWAY
                                                                                                                            Page 1 of 2
                                                   NONCARCINOGENIC RISKS TO TRESPASSERS
Contaminants of Concern
Volatile Organic Compounds
Benzene
1,2-Dichloroethane
1,4-Dichlorobenzene
Dichlorodifluoromethane
Ethylbenzene
Methylene Chloride
Tetrachloroethylene
Toluene
1,1,1-Trichloroethane
Trichloroethylene
Vinyl Chloride
   Modeled Concentration
Landfill Area A    Hot Spot
           (mg/m3)
Exposure Factor
     Child
  (m3/kg/day)
       Exposure Dose           Reference     Toxicity          HAZARD INDEX
Landfill Area A    Hot Spot       Dose       Endpoint  Landfill Area A    Hot Spot
        (mg/kg/day)             (mg/kg/day)                  Child            Child
4.30E-04
3.10E-05
8.30E-05
3.30E-06
5.10E-04
2.30E-06
4.50E-06
2.90E-05
3.60E-06
3.60E-06
1.
2,
3,
2,
4,
1.
3,
5,
2,
2,
.70E-05
.30E-05
. OOE-05
.50E-05
. 90E-05
. 80E-05
. 40E-05
.OOE-05
. 80E-05
.70E-05
3.
3.
3.
3.
3.
3.
3.
3.
3.
3.
, 8E-03
, 8E-03
, 8E-03
, 8E-03
, 8E-03
, 8E-03
, 8E-03
, 8E-03
, 8E-03
, 8E-03
1.
1.
3,
1.
1.
8,
1.
1.
1.
1.
. 6E-06
.2E-08
.2E-07
.3E-08
.9E-08
.7E-09
.7E-08
.1E-07
.4E-08
.4E-08
6,
8,
1.
9,
1.
6,
1.
1.
1.
1.
.5E-08
.7E-06
. 1E-07
.5E-08
. 9E-08
. 8E-08
. 3E-07
. 9E-07
. 1E-07
. OE-07


2,
5,
2,


1.
2,

—
-
.3E-01
.7E-02
. 9E-01
-
-
. OE-01
. 9E-01
-
—
—
Liver
Liver
Fetotox
—
-
Liver
Liver
--


1.
2.
6.

-
1.
4.

—
—
4E-06
2E-07
7E-06
—
-
1E-06
7E-08
--
—
—
5. OE-07
1.7E-06
6.4E-07
—
—
1.9E-06
3.7E-07
--
   3.40E-06
                   2.00E-03
                                  3.8E-03
                                                     1.3E-08
                                                                   7.6E-06
                                                                                                                               SUM       9.4E-06         5.1E-06
Exposure Factor
  Inhalation - 0.83 m3 of air inhaled per hour for 2 hours per day of exposure for 36 days of exposure in a 365 day year by a 43 kg child = 3.8 x 10-3 m3/kg/day

-------
                                                                  TABIiE 13
                                                           DAVIS GSR LANDFILL SITE
                                                  OFF-SITE LANDFILL GAS INHALATION PATHWAY
                                                                                                           Page 1 of  1
                                                       CARCINOGENIC RISKS TO RESIDENTS
Contaminants of Concern
Volatile Organic Compounds
Benzene
1,2-Dichloropropane
1,4-Dichlorobenzene
Dichlorodifluoromethane
Ethylbenzene
Methylene Chloride
Tetrachloroethylene
Toluene
Trichloroethylene
Vinyl Chloride
Modeled Concentration
Off-site    Residence
        (mg/m3)
Exposure Factor
     Adult
  (m3/kg/day)
    Exposure Dose         Cancer     Weight
Off-site    Residence  Slope Factor     of
     (mg/kg/day)       (mg/kg/day)-1  Evidence
2.01E-05
1.63E-07
3.90E-06
1.74E-07
2.37E-05
1.22E-07
2.39E-07
1.40E-06
1.89E-07
1.87E-06
1.
1.
2,
1.
1.
7,
1.
8,
1.
1.
.25E-05
. 02E-07
.43E-06
. 09E-07
.48E-05
. 65E-08
. 49E-07
.71E-07
.18E-07
.18E-06
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
.2E-01
.2E-01
.2E-01
.2E-01
.2E-01
.2E-01
.2E-01
.2E-01
.2E-01
.2E-01
2,
2,
4,
2,
2,
1.
2,
1.
2,
2,
.4E-06
. OE-08
.7E-07
. IE-OS
.8E-06
.5E-08
. 9E-08
.7E-07
.3E-08
.2E-07
1.
1.
2,
1.
1.
9,
1.
1.
1.
1.
.5E-06
.2E-08
. 9E-07
.3E-08
.8E-06
.2E-09
.8E-08
. OE-07
.4E-08
. 4E-07

9



1.
2

6
3
2.9E-02
.1E-02
-
-
—
65E-03
.OE-03
—
.OE-03
.OE-03
A
B2
C
D
D
B2
B2
D
B2
D
                                                                                                                        SUM
 Exposure Factor:
  Inhalation - 20 m3 of air inhaled per day for 365 days in a 365 day year for 30 years in a 70 year lifetime by  a  70  kg  adult
    RISK ESTIMATE
Off-site     Residence
  Adult        Adult
                                                                                                  7.OE-08
                                                                                                  1.8E-09
                                                                                    4.4E-08
                                                                                    1.1E-09
2.4E-11
5.7E-11
1.4E-10
6.7E-08
1.5E-11
3.6E-11
8.5E-11
4.2E-08
                                                                                                  1.4E-07       8.7E-C

                                                                                                  1.2x10-1 m3/kg/day

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                                                                  TABIiE 13
                                                           DAVIS GSR LANDFILL SITE
                                                  OFF-SITE LANDFILL GAS INHALATION PATHWAY
                                                                                                          Page 2  of  2
                                                       CARCINOGENIC RISKS TO RESIDENTS
Contaminants of Concern
Volatile Organic Compounds
Benzene
1,2-Dichloroethane
1,4-Dichlorobenzene
Dichlorodifluoromethane
Ethylbenzene
Methylene Chloride
Tetrachloroethylene
Toluene
Trichloroethylene
Vinyl Chloride
Modeled Concentration
Off-site    Residence
        (mg/m3)
Exposure Factor
     Adult
  (m3/kg/day)
    Exposure Dose       Reference   Toxicity
Off-site    Residence       Dose    Endpoint
     (mg/kg/day)         (mg/kg/day)
    HAZARD INDEX
Off-site     Residence
  Adult        Adult
2,
1.
3,
1.
2,
1.
2,
1.
1.
1.
. 01E-05
. 63E-07
. 90E-06
.74E-07
.37E-05
.22E-07
.39E-07
.40E-06
. 89E-07
.87E-06
1.
1.
2,
1.
1.
7,
1.
8,
1.
1.
.25E-05
. 02E-07
.43E-06
. 09E-07
.48E-05
. 65E-08
. 49E-07
.71E-07
.18E-07
.18E-06
2,
2,
2,
2,
2,
2,
2,
2,
2,
2,
.7E-01
.7E-01
.7E-01
.7E-01
.7E-01
.7E-01
.7E-01
.7E-01
.7E-01
.7E-01
5,
4,
1.
4,
6,
3,
6,
3,
5,
5,
.4E-06
. 4E-08
. 1E-06
.7E-08
.4E-06
.3E-08
.5E-08
. 8E-07
. IE-OS
. OE-07
3,
2,
6,
2,
4,
2,
4,
2,
3,
3,
.4E-06
.8E-08
. 6E-07
. 9E-08
.OE-06
. IE-OS
. OE-08
. 4E-07
.2E-08
.2E-07
—
—
2.3E-01
5.7E-02
2.9E-02
—
—
l.OE-01
—
--
-
—
Liver
Liver
Fetotox
—
—
Liver
—
--


4,
8,
2,


3,


—
—
. 6E-06
.2E-07
.2E-05
—
—
.8E-06
—
—


2,
5,
1.


2,


—
—
. 9E-06
.2E-07
. 4E-05
—
—
.4E-06
—
--
                                                                                                                        SUM
                                                                                                                                  3.1E-05      1.9E-05
Exposure Factor:
  Inhalation - 20 m3 of air inhaled per day for 365 days in a 365 day year by a 70  kg adult =  2.7x10-1 m3/kg/day

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Table B-10 in Appendix B depicts the carcinogenic and non-carcinogenic risk summary for all media
evaluated to reflect present and potential future exposure pathways corresponding to the average and the
reasonable maximum exposure  (RME) scenarios.

     B.    Ecological Risk Assessment

A Baseline Ecological Risk Assessment was conducted to assess potential risks to ecological resources
near the landfill.  Three natural resources in the immediate vicinity of the landfill are of concern in
the ecological assessment:  the surrounding wetlands and streams, the aguifers underlying the landfill,
and the forested land around the Site.

Contaminant concentrations in sediments found at the Davis GSR wetlands were compared to Sediment Quality
Criteria (SQC) ,  established to provide guidance for the protection of ecological receptors from either
direct or indirect exposure to contaminated sediments.  Various sediment guality criteria and guidelines
were used to select contaminants of concern in sediments, including Ontario MOE sediment criteria, most
abundant for metals, EPA Interim Sediment Criteria, established for a limited number of organic
compounds,  and National Oceanic and Atmospheric Administration (NOAA) Sediment Effect Levels, developed
as guidance values only and are not intended for use in deriving regulatory standards.  For both, the
Nine Foot Brook and unnamed stream, several inorganics exceeded SQC at a location, but there are only
sporadic exceedances for the organic compounds, indicating possible adverse effect on the benthic
invertebrate community.  To investigate these possible impacts further, in July 1993, a benthic
macroinvertebrate survey was conducted at three locations in the wetlands.  The survey showed that the
benthic invertebrate community was moderately impaired at one of these locations.  The stress on the
community appeared to be only moderate because pollution-sensitive species had not been replaced by
pollution-tolerant species.  Since this survey was performed during drought, the impairment observed may
reflect changes in habitat guality and/or availability, rather than being directly attributable to
sediment contamination from the Davis GSR landfill.

Contaminant concentrations detected in site surface water were compared to chronic Ambient Water Quality
(AWQC), also referred to as the Criteria Criterion Continuous Concentration (CCC), which is a lower, more
protective value than acute AWQC.  AWQC are used to guantify levels at which toxicity to aguatic
organisms may occur.  For every surface water sampling location there was at least one inorganic chemical
concentration that exceeded AWQC CCC. When a CCC is exceeded, deterious effects to resident species may
or may not have occurred, depending on whether the elevated contaminant concentrations are persistent. In
addition, co-factors, such as TSS and hardness, influence bioavailability and the toxicity of total
inorganics in surface water.  A majority of the total inorganic compounds that exceeded AWQC CCC were
detected in fall 1992, when high levels of TSS were also measured during low flow and minimal flushing
period, indicating that these concentrations are probably not persistent throughout the year.

To assess potential risks to benthic invertebrates, the implication of comparison with SQCs and AWQC CCC
were evaluated with consideration to the value of the wetlands and the availability of additional
surrounding wetlands. A gualitative assessment of the wetland was performed using the WETII Model, which
uses several factors to evaluate the ecological significance of the wetland area.  Aguatic
diversity/abundance were rated low as the streams near the landfill are generally slow and shallow and do
not appear to provide viable fish habitat.  Wildlife diversity/abundance were also low, except for high
effectiveness for breeding and migration, since palustrine wetlands are generally expected to provide
abundant habitat for wetland-dependent wildlife. If a reduction of aguatic biota or benthic invertebrate
populations occurs in these wetlands, it is not expected to dramatically affect the food supply of the
higher species.

Species-specific food-chain exposure models for the short-tailed shrew, the American woodcock, and the
red-tailed hawk, indicate that populations of these three key species of wildlife are not expected to be
impacted by the landfill.

Summary of Conclusions Concerning Site Risks

The only samples which showed concentrations of chemical contaminants  (arsenic) which were at the upper
end of the acceptable risk range (i.e., 10-4)  or a hazard index  (manganese) which may present a level of
concern for a human health drinking water scenario (HI=8.4), assuming that ground water at this location
is ingested as a sole source of drinking water, were detected at monitoring wells located in the wetlands
between the landfill and the Nine Foot Brook.   This is a very conservative estimate of future exposure,
however, as this location is immediately adjacent to the landfill. Exposure to groundwater as a drinking
water source in this limited area is unlikely due to the steep slopes and proximity to the wetlands which
would preclude development and use of groundwater at this location for future water supplies. At this
location, near the toe of the landfill, MCLs were slightly exceeded for the following compounds:
benzene, chromium, and nickel.  A secondary MCL was exceeded for manganese.

-------
The estimated cancer risk associated with exposure to contamination at the Site falls within EPA's
acceptable risk range  (10-4 to 10-6).   All current and future risks attributable to exposures associated
with inhalation landfill gas, and ingestion of, or contact with, the surficial soils, surface water and
sediment are below the lower end of the acceptable risk range (i.e., 10-6).  No current health risks are
associated with exposure to groundwater at the Site, since the contaminated groundwater is not being used
for drinking water. No plume of contamination was found emanating from the landfill.  The risk of
groundwater ingestion as a drinking water source was estimated at the upper end of the acceptable risk
range  (i.e., 10-4) attributable largely to the presence of arsenic, which is present, however, at levels
below those established as safe in the Safe Drinking Water Act.

The Site specific conditions at the Davis GSR Landfill Site support the decision to take no further
action.  All of the estimated maximum cancer risks to human health associated with exposure to
contamination at the Site fall within EPA's acceptable risk range.  In addition, non-cancer adverse
health effects are not likely at this Site since the future use of site groundwater is very unlikely due
to existing topographical and wetland considerations and no contaminated groundwater plume is found
migrating off-site. Thus no exposure and hence no unacceptable risks are expected to occur.

Results of the ecological risk assessment also indicate that, given the abundance of surrounding water
bodies and wetlands, it is unlikely that a reduction in viable wetland habitat associated with the
landfill would adversely impact waterfowl, wetland insectivores (such as the shrew), and
wetland-dependent birds.

The site is not expected at the present time or in the future to present an imminent and substantial
endangerment to public health, welfare, or the environment. Thus,  a no action decision has been chosen
for this site.

VII.  DESCRIPTION OF NO ACTION ALTERNATIVE

There are no construction activities associated with the No Action decision. Monitoring of groundwater,
however, will be conducted to verify that no unacceptable exposures occur in the future.  At a minimum,
five years of monitoring, including residential well monitoring, will be performed.

VIII.  DOCUMENTATION OF SIGNIFICANT CHANGES

EPA presented a Proposed Plan (preferred alternative) on June 23,  1997 for the Site based on the results
of both the human health risk assessment and ecological risk evaluation performed as part of the remedial
study.  The Proposed Plan described EPA's proposal to take no further action under CERCLA at the Davis
GSR Landfill Site.  No significant changes have been made to the No Action recommendation described in
the Proposed Plan.

IX.   STATE ROLE

The Rhode Island Department of Environmental Management has reviewed the preferred alternative and has
indicated its support for the No Action decision. The State of Rhode Island concurs with the selected
remedy for the Davis GSR Landfill Site. A copy of the declaration of concurrence is attached as Appendix
C.

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                              DAVIS GSR LANDFILL SUPERFUND SITE

                                          APPENDIX A

                                 ADMINISTRATIVE RECORD INDEX

                                       Davis GSR Landfill
                                            NPL Site

                                     Administrative Record
                                              INDEX

                                    Compiled: June 16, 1997
                                ROD Issued: September 29, 1997

                                           Prepared By
                                         EPA New England
                           Office of Site Remediation & Restoration
                             U.S. Environmental Protection Agency

                                     With Assistance From
                                             ads
                                    2070 Chain Bridge Road
                                       Vienna, VA 22182

                                        INTRODUCTION

This is Index to the Administrative Record compiled at the time that the Record of Decision  (ROD) was
signed for the Davis Glocester-Smithfield Regional (GSR)  Landfill Superfund site. Included in the Index
are citations for site-specific documents used by Environmental Protection Agency (EPA) staff in
selecting the response action described in the ROD.  Within the Administrative Record, documents are
arranged in order by the Document Number that appears at the end of each citation in the Index.

The Administrative Record is available for public review at the EPA Region I Office of Site Remediation
and Restoration  (OSRR) Records Center, 90 Canal Street, Boston, MA, and the Davis GSR Landfill Superfund
site records repository, currently located at the East Smithfield Public Library, 50 Esmond Street,
Esmond, RI.   The staff of the EPA Region I OSRR Records Center asks that you set up an appointment in
advance to review the Administrative Record by calling telephone number (617) 573-5729.

Access to certain documents in the Administrative Record is limited. Documents cited in the Index with
the notation, [Available in EPA Records Center], are stored only at the EPA Region I OSRR Records Center.
Documents cited in the Index with the notation, [Confidential], are documents available only for judicial
review and are stored only at the EPA Region I OSRR Records Center.

Questions concerning the content of the Davis GSR Landfill Administrative Record should be addressed to
the EPA Region I OSRR staff member assigned oversight responsibility for this site.

An Administrative Record is reguired pursuant to the Comprehensive Environmental Response, Compensation
and Liability Act (CERCLA), as amended by the Superfund Amendments and Reauthorization Act  (SARA).

             Davis GSR Landfill Administrative Record: Table of Contents

Volume I               000001-000020
Volume II              000021-000145
Volume III             000146
Volume IV              000147
Volume V               000148-000156
Volume VI              000157-000206

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01.02
        PRE-REMEDIAL RECORDS - PRELIMINARY ASSESSMENT
        Title:        Potential Hazardous Waste Site Identification and Preliminary Assessment with
                     National Priorities List Checklist of Data Requirements.
        Addressee:    US EPA/REGION I
        Authors:      DENNIS DUMONT - ECOLOGY & ENVIRONMENT, INC.
        Date:         April 16, 1982
        Format:       FORM                          No. Pgs:   7
        AR No.        01.02.1                       Document No.   000001

        Title:        CERCLIS Pre-Remedial Site Management Form  (Version 1.0).
        Date:         December 10,  1987
        Format:       FORM                          No. Pgs:   1
        AR No.        01.02.2                       Document No.   000002

01.03  PRE-REMEDIAL RECORDS - SITE INSPECTION

       Title:         NUS Sampling Activity at Davis GSR Landfill and VOA Screening Results.
       Authors:       NUS CORPORATION
       Date:          July 27, 1984
       Format:        REPORT, STUDY                 No. Pgs:   9
       AR No.         01.03.1                       Document No.   000003

       Title:         Sampling Data Results,  Case No. 3407, for October 15 to October 17, 1984 Sampling
                     Round.
       Addressee:     US EPA/REGION I
       Authors:       SPECTRIX CORPORATION
       Date:          January 11,  1985
       Format:        SAMPLING & ANALYSIS DATA      No. Pgs:   209
       AR No.         01.03.2                       Document No.   000004
       Title:         Additional Purge Data for Case No. 3407.
       Addressee:     US EPA/REGION I
       Authors:       SPECTRIX CORPORATION
       Date:          May 14,  1985
       Format:        SAMPLING & ANALYSIS DATA      No. Pgs:   94
       AR No.         01.03.3                       Document No.
                                                                  000005
       Title:         Final Site Inspection Report, Davis GSR Landfill, Glocester, Rhode Island.
       Authors:       NUS CORPORATION
       Date:          October 31,  1985
       Format:        REPORT, STUDY                 No. Pgs:   97
       AR No.         01.03.4                       Document No.   000006

01.04  PRE-REMEDIAL RECORDS - RECORDS RELATED TO CERCLIS

       Title:         National Priorities List Site, Davis GSR Landfill.
       Authors:       US EPA/REGION I
       Format:        FACT SHEET,  PRESS RELEASE     No. Pgs:   1
       AR No.         1.04.1                        Document No.   000011

       Title:         Information Requirements for Evaluation of a Proposed Sanitary Landfill.
       Addressee:     WILLIAM DAVIS
       Authors:       FRANK B. STEVENSON - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
       Date:          July 22, 1974
       Format:        LETTER                        No. Pgs:   2
       AR No.         01.04.2                       Document No.   000012
       Title:         Letter Identifying Need for a Permit Application Prior to Development of Wetland
                     Areas on Proposed Sanitary Landfill Site.
       Addressee:     WILLIAM DAVIS
       Authors:       JOHN S. QUINN,  JR. - RI DEPT OF HEALTH/SOLID
                     WASTE MANAGEMENT
       Date:          July 31,  1974
       Format:        LETTER                        No. Pgs:   2
       AR No.         01.04.3                       Document No.   000013

-------
Title:        Wetlands Issues Pertaining to the Proposed Sanitary Landfill Development in
              Glocester.
Addressee:    RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
Authors:      ALBERT A. KURLINDEN - RI DNR/PLANNING & DEVELOPMENT
Date:         August 12,  1974
Format:       MEMORANDUM                    No. Pgs:   2
AR No.        01.04.4                       Document No.   000014

Title:        Transmittal Letter for a Consent Order Agreement not to Permit Open Burning at
              Smithfield Sanitary Landfill.
Addressee:    DOMENIC TUDINO - ATTORNEY FOR WILLIAM DAVIS
Authors:      ANTHONY S.  DELGIUDICE - RI DEPT OF HEALTH/LEGAL SERVICES
Date:         October 4,  1974
Format:       LETTER                        No. Pgs:   1
AR No.        01.04.5                       Document No.   000015

Title:        Transmittal Letter for Plans Pertaining to the Proposed Glocester Sanitary Landfill.
Addressee:    RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
              PHILIP S. MANCINI, JR. - AMERICAN ENGINEERING CORP.
Date:         October 15, 1974
Format:       LETTER                        No. Pgs:   1
AR No.        01.04.6                       Document No.   000007

Title:        Solid Waste Disposal Facilities Operating in Compliance with Rhode Island
              Regulations.
Addressee:    WILLIAM DAVIS
Authors:      FRANK B. STEVENSON - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
Date:         January 15, 1975
Format:       LETTER                        No. Pgs:   1
AR No.        01.04.7                       Document No.   000016

Title:        Summary of a Site Visit to Glocester-Smithfield Regional Landfill.
Authors:      FRANK B. STEVENSON, JAMES CULLINANE - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
Date:         February 20, 1975
Format:       MEMORANDUM                    No. Pgs:   2
AR No.        01.04.8                       Document No.   000017

Title:        Glocester-Smithfield Regional Landfill Inspection Results and Recommendations.
Authors:      CARLETON A. MAINE - RI DOH/WATER SUPPLY & POLLUTION CONTROL
Date:         February 24, 1975
Format:       MEMORANDUM                    No. Pgs:   2
AR No.        01.04.9                       Document No.   000018

Title:        Letter Describing Concerns About the Impact of the New Glocester Landfill on
              Waterman Lake and Nine Foot Brook.
Addressee:    JOHN S. QUINN, JR. - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
Authors:      JOHN BIGGINS - CITIZENS FOR PRESERVATION WATERMAN LAKE
Date:         February 27, 1975
Format:       LETTER                        No. Pgs:   3
AR No.        01.04.10                      Document No.   000019

Title:        Report on Design and Operation of Sanitary Landfill for William Davis at  (GSR)
              Landfill, Tarkiln Road, Glocester, RI.
Authors:      MICHAEL N.  GARRETT & ASSOCIATES
Date:         June 1976
Format:       REPORT, STUDY                 No. Pgs:   25
AR No.        01.04.11                      Document No.   000009
Title:        Mechanical Analysis of Project Site Grab Sample.
Authors:      GEORGE J GEISSER JR. CORP.
Date:         November 4, 1976
Format:       REPORT, STUDY                 No. Pgs:   2
AR No.        01.04.12                      Document No.   000008

-------
       Title:         Operations Plan 1979 to 1981, L & R Resources Corp. Sanitary Landfill,
                     Glocester-Smithfield, Rhode Island [Maps available at EPA Records Center]
       Authors:       ALLINSON INC.
       Date:          1979
       Format:        REPORT,  STUDY
       AR No.         01.04.13
No. Pgs:   34
Document No.
                                                                  000010
01.05  PRE-REMEDIAL RECORDS - CORRESPONDENCE RELATED TO CERCLIS

       Title:         Letter Addressing Contamination Concerns at Nine Foot Brook and Its Tributary.
       Addressee:     WILLIAM DAVIS
       Authors:       JOHN S. QUINN, JR. - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
       Date:          February 28,  1975
       Format:        LETTER                        No. Pgs:   2
       AR No.         01.05.1                       Document No.   000020

       Title:         Letter from Town of Glocester Detailing Concerns about Pollution in Nine Foot Brook.
       Addressee:     JOHN S. QUINN, JR. - RI DEPT OF HEALTH/DIV OF SOLID WASTE
       Authors:       JOSEPH T. TRAINOR - TOWN OF GLOCESTER
       Date:          March 6, 1975
       Format:        LETTER                        No. Pgs:   2
       AR No.         01.05.2                       Document No.   000022

       Title:         Letter Describing Corrective Measures Planned for Glocester Landfill to Comply with
                     Solid Waste Management Regulations.
       Addressee:     JOHN S. QUINN, JR. - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
       Authors:       PHILIP S. MANCINI, JR. - AMERICAN ASSOCIATES INC.
       Date:          March 20, 1975
       Format:        LETTER                        No. Pgs:   2
       AR No.         01.05.3                       Document No.   000021

       Title:         Solid Waste Regulation Reguirements for the Installation of Groundwater Monitoring
                     Wells.
       Addressee:     WILLIAM DAVIS
       Authors:       FRANK B. STEVENSON - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
       Date:          December 9, 1975
       Format:        LETTER                        No. Pgs:   2
       AR No.         01.05.4                       Document No.   000023

       Title:         Letter Summarizing Time Guidelines for Solid Waste Management Regulations.
       Addressee:     WILLIAM DAVIS
       Authors:       FRANK B. STEVENSON - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
       Date:          December 16,  1975
       Format:        LETTER                        No. Pgs:   2
       AR No.         01.05.5                       Document No.   000024

       Title:         Letter Describing the Regulatory Status of Glocester-Smithfield Regional Landfill.
       Addressee:     DENNIS BOUCHARD - ESMOND TOWN COUNCIL
                     JOHN S. QUINN, JR. - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
       Date:          January 5,  1976
       Format:        LETTER                        No. Pgs:   3
       AR No.         01.05.6                       Document No.   000025
       Title:         Reguirements for State Grant-in-Aid Funds for Cities and Towns Presently Using the
                     Davis GSR Facility.
       Addressee:     LEONARD A. KIERNAN - KEENAN, RICE, DOLAN, REARDON & KIERNAN
       Authors:       ANTHONY S. DELGIUDICE - RI DEPT OF HEALTH/LEGAL SERVICES
       Date:          January 12,  1976
       Format:        LETTER                        No. Pgs:   2
       AR No.         01.05.7                       Document No.   000026

-------
Title:        Agreements Reached During an April 19, 1976 Enforcement Meeting Regarding Operations
              at Glocester-Smithfield Regional Landfill.
Addressee:    BRUCE GOODWIN - RI DNR/PLANNING & DEVELOPMENT
Authors:      JOHN S. QUINN, JR. - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
Date:         April 19, 1976
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.8                       Document No.   000027

Title:        Summary of Items Contained in the February 24, 1976 Consent Order between the Rhode
              Island Department of Health and William Davis.
Addressee:    GLENN KUMEKAWA - RHODE ISLAND GOVERNOR'S OFFICE
Authors:      JOHN S. QUINN, JR. - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
Date:         June 4, 1976
Format:       MEMORANDUM                    No. Pgs:   2
AR No.        01.05.9                       Document No.   000028

Title:        Response to Senator Pell's Inguiry Into the Operation of the Glocester-Smithfield
              Regional Landfill.
Addressee:    CLAIRBORNE PELL - UNITED STATES SENATE
Authors:      JOHN S. QUINN, JR. - RI DEPT OF HEALTH/SOLID WASTE MANAGEMENT
Date:         June 21, 1976
Format:       LETTER                        No. Pgs:   2
AR No.        01.05.10                      Document No.   000030

Title:        Suggested Self-Monitoring Locations of the Seasonal Streams at the GSR Landfill.
Addressee:    WILLIAM DAVIS
Authors:      CARLETON A. MAINE - RI DOH/WATER SUPPLY & POLLUTION CONTROL
Date:         August 26, 1976
Format:       LETTER                        No. Pgs:   2
AR No.        01.05.11                      Document No.   000031

Title:        Corrected Copy of the Solid Waste Management Facility License Issued to William
              Davis d/b/a GSR Landfill, March 7, 1977, with Transmittal Letter.
Addressee:    WILLIAM DAVIS - GSR LANDFILL
Authors:      RHODE ISLAND DEPART14ENT OF HEALTH
Date:         March 7, 1977
Format:       LETTER                        No. Pgs:   2
AR No.        01.05.12                      Document No.   000032

Title:        Denial of Application to Renew Solid Waste Management License for GSR Landfill.
Addressee:    WILLIAM DAVIS
Authors:      JOHN S. QUINN, JR. - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
Date:         January 19, 1978
Format:       LETTER                        No. Pgs:   2
AR No.        01.05.13                      Document No.   000033

Title:        Reguest by Mr. Davis for a Hearing on the Determination of His Solid Waste Disposal
              License.
Addressee:    JOHN S. QUINN, JR. - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
Authors:      THOMAS C. PLUNKETT - RICE, DOLAN, KIERNAN & KERSHAW
Date:         January 25, 1978
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.14                      Document No.    000034
Title:        Site Plan for Operation for the Calendar Year 1978.
Addressee:    JOHN S. QUINN, JR. - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
Authors:      WILLIAM DAVIS - GSR LANDFILL
Date:         January 27, 1978
Format:       LETTER                        No. Pgs:   2
AR No.        01.05.15                      Document No.   000035

-------
Title:        Letter Informing Smithfield Town Council of an Application for a Landfill Operation
              within the Town of Smithfield.
Addressee:    FRANK G. ELDREDGE -
Authors:      FRANK B. STEVENSON - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
Date:         June 27, 1978
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.16                      Document No.   000036

Title:        Request for Documentation on the Town of Smithfield's Contractual Relationship with
              the Operator of GSR Landfill.
Addressee:    FRANK G. ELDREDGE -
Authors:      JOHN S. QUINN, JR. - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
Date:         July 12, 1978
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.17                      Document No.   000037

Title:        Correction of Violations at Davis Landfill.
Addressee:    LEONARD A. KIERNAN - RICE, DOLAN, KIERNAN &  KERSHAW
Authors:      FRANK B. STEVENSON
Date;         August 7, 1978
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.18                      Document No.   000038

Title:        Town Concerns about Renewal of License to Operate GSR Landfill.
Addressee:    JOHN S. QUINN, JR. - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
Authors:      JACQUILINE A. ERICSON - TOWN OF GLOCESTER
Date:         August 24, 1978
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.19                      Document No.   000039
Title:        Notice of Deficiencies in Mr. Davis' Application for a Renewal of His License
              Operate a Solid Waste Management Facility.
Addressee:    WILLIAM DAVIS - GSR LANDFILL
Authors:      FRANK B. STEVENSON - RI DEPT OF HEALTH/DIV OF LAND RESOURCES
Date:         November 30, 1978
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.20                      Document No.   000040
to
Title:        Summary of Discussions Held on December 11, 1978 between RIDOH and Mr. Davis
              Regarding Plans for GSR Landfill.
Addressee:    WILLIAM DAVIS - GSR LANDFILL
Authors:      FRANK B. STEVENSON - RI DEPT OF HEALTH/DIV OF LAND RESOURCES
Date:         December 13, 1978
Format:       LETTER                        No. Pgs:   2
AR No.        01.05.21                      Document No.   000041

Title:        Glocester Residents Object to Licensing of Davis GSR Landfill.
Addressee:    JOHN S. QUINN, JR. - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
Authors:      MARILYN LOWNEY
Date:         April 26, 1979
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.22                      Document No.   000042

Title:        Operation of Davis Landfill on Steere Property and Other Concerns.
Addressee:    JOHN S. QUINN JR. - RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
Authors:      MONROE ALLEN
Date:         May 7, 1979
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.23                      Document No.   000043
Title:        Response to Inquiry into Mr. Davis' Solid Waste Disposal License and Allegations of
              GSR Dumping Refuse in Smithfield.
Addressee:    R. DANIEL PRENTISS - RI DEPT OF ENV MGMNT/OFFICE OF DIRECTOR
Authors:      MONROE ALLEN
Date:         May 23, 1979
Format:       LETTER                        No. Pgs:   1
AR No.        01.05.24                      Document No.   000044

-------
       Title:         Letter Iterating Decision to Terminate Mr. Davis' License to Operate GSR Landfill on
                     December 18,  1978.
       Addressee:     WILLIAM DAVIS - GSR LANDFILL
       Authors:       W.  EDWARD WOOD - RI DEPT OF ENV MGMNT/OFFICE OF DIRECTOR
       Date:          August 18, 1981
       Format:        LETTER                        No. Pgs:    2
       AR No.         01.05.25                      Document No.   000045

       Title:         Reguest for a US EPA Field Investigation of Conditions at the Davis GSR Landfill.
       Addressee:     JOHN CHAFEE - UNITED STATES SENATE
       Authors:       GLORIA P. NARNEY -
       Date:          November 27,  1981
       Format:        LETTER                        No. Pgs:    1
       AR No.         01.05.26                      Document No.   000149

       Title:         US  EPA Advised of Smithfield Town Council's Concern About Conditions at Davis GSR
                     Landfill.
       Addressee:     LESTER SUTTON - US EPA/REGION 1
                     JOHN CHAFEE - UNITED STATES SENATE
       Date:          December 4, 1981
       Format:        LETTER                        No. Pgs:    1
       AR No.         01.05.27                      Document No.   000150

       Title:         US  EPA's Response to Senator Chafee's Inguiry on Behalf of the Smithfield Town
                     Council.
       Addressee:     JOHN CHAFEE - UNITED STATES SENATE
       Authors:       LESTER SUTTON - US EPA/REGION I
       Date:          December 23,  1981
       Format:        LETTER                        No. Pgs:    1
       AR No.         01.05.28                      Document No.   000151

       Title:         Letter Identifying a May 6, 1982 Deadline for Submitting Landfill Operation Plans.
       Addressee:     WILLIAM DAVIS - GSR LANDFILL
       Authors:       CARLETON A. MAINE - RI DEPT OF ENV MGMNT/OFFICE OF DIRECTOR
       Date:          April 14, 1982
       Format:        LETTER                        No. Pgs:    2
       AR No.         01.05.29                      Document No.   000046

02.02  REMOVAL RESPONSE  - REMOVAL RESPONSE REPORTS

       Title:         US  EPA/Technical Assistance Team, Davis Landfill, Glocester, Rhode Island.
       Authors:       US  EPA/TECHNICAL ASSISTANCE TEAM
       Date:           1988
       Format:        REPORT, STUDY                 No. Pgs:    39
       AR No.         02.02.1                       Document No.   000047

       Title:         Removal Assessment, August 24, 1990,  Davis Landfill, Glocester/Smithfield, RI
                     (Photographs available at EPA Records Center].
       Addressee:     RICHARD C. BOYNTON - US EPA/REGION I
       Authors:       JOSEPH F. LEMAY, STEPHEN MANGION - US EPA/REGION I
       Date:          September 20, 1990
       Format:        REPORT, STUDY                 No. Pgs:    12
       AR No.         02.02.2                       Document No.   000048

       Title:         Davis GSR Landfill NPL Site Investigation, with attachments.
       Authors:       US  EPA/REGION I
       Date:          September 20, 1990
       Format:        MEMORANDUM                    No. Pgs:    12
       AR No.         02.02.3                       Document No.   000049
       Title:         Removal Program,  NPL Site Investigation for Davis GSR Landfill, Glocester, Rhode
                     Island.
       Authors:       US EPA/TECHNICAL ASSISTANCE TEAM
       Date:          November 1990
       Format:        REPORT, STUDY                 No. Pgs:   42
       AR No.         02.02.4                       Document No.   000050

-------
       Title:         Davis GSR Landfill: Results of Site Visits on 12/20/90 and 1/3/91.
       Authors:       JOSEPH F. LEMAY - US EPA/REGION I
       Date:          February 7,  1991
       Format:        MEMORANDUM                    No. Pgs:    15
       AR No.         02.02.5                       Document No.   000051
       Title:         Methane Emissions from Davis GSR Landfill Noted During a June 26,
                     Inspection,  with Landfill Map.
       Addressee:     US EPA/REGION I
       Authors:       COM/FEDERAL PROGRAMS CORPORATION
       Date:          December 31, 1991
       Format:        SAMPLING & ANALYSIS DATA      No. Pgs:   2
       AR No.         02.02.6                       Document No.   000099
1991 Site
03.01  REMEDIAL INVESTIGATION - CORRESPONDENCE

       Title:         Davis GSR Landfill Superfund Site, 11/11/92 (Round 1) Residential Well Sampling
                     Results, [Available in EPA Records Center].
       Authors:      JOSEPH F. LEMAY - US EPA/REGION I
       Date:          May 28,  1993
       Format:        LETTER
       AR No.         03.01.1                       Document No.    000101

       Title:         Davis GSR Landfill Superfund Site, 5/12/93 (Round 2)  Residential Well Sampling
                     Results  [Confidential].
       Authors:      JOSEPH F. LEMAY - US EPA/REGION I
       Date:          January 25,  1994
       Format:        LETTER
       AR No.         03.01.2                       Document No.    000102

03.02  REMEDIAL INVESTIGATION - SAMPLING & ANALYSIS DATA

       Title:         Certificates of Analysis for Surface Water (1974-1982).
       Addressee:     SMITHFIELD CONSERVATION COMMISSION
       Authors:      NEW ENGLAND TESTING LABORATORY, INC.
       Date:          November 9,  1974
       Format:        REPORT,  STUDY                 No. Pgs:   7
       AR No.         03.02.1                       Document No.    000179

       Title:         Davis GSR Landfill Well Sample Data Results (1980-1984).
       Date:          December 9,  1980
       Format:        MISCELLANEOUS                 No. Pgs:   37
       AR No.         03.02.2                       Document No.    000182

       Title:         Groundwater Monitoring at GSR Landfill.
       Addressee:     SEAN 0.  COFFEY - RI DEPT OF ENVIRONMENTAL MANAGEMENT
       Authors:      FRANK B. STEVENSON - RI DEM/AIR AND HAZARDOUS MATERIALS
       Date:          October 23,  1981
       Format:        MEMORANDUM                    No. Pgs:   2
       AR No.         03.02.3                       Document No.    000180

       Title:         Analytical Results from the Davis Landfill.
       Addressee:     BARBARA IKALAINEN - RI DEM/AIR AND HAZARDOUS MATERIALS
       Authors:      CLARA CHOW,  PI-YUN TSAI - US EPA/DRINKING WATER BRANCH
       Date:          December 22, 1981
       Format:        MEMORANDUM                    No. Pgs:   29
       AR No.         03.02.4                       Document No.    000181
       Title:         Logs for Monitoring Wells Drilled at the Davis GSR Landfill site.
       Addressee:     JOSEPH F. LEMAY - US EPA/REGION I
       Authors:       RON BOYD - GUILD DRILLING CO.
       Date:          January 31,  1991
       Format:        LETTER                        No. Pgs:   11
       AR No.         03.02.5                       Document No.   000184

-------
       Title:        Residential Well Analytical Results Summary  Organics  [Confidential].
       Addressee:    JULIA NAULT - CDM/FEDERAL PROGRAMS CORPORATION
       Authors:       SUSAN HENDERSON - CDM/FEDERAL PROGRAMS CORPORATION
       Date:         February 2, 1993
       Format:        MEMORANDUM                    No. Pgs:   35
       AR No.        03.02.6                       Document No.   000185
       Title:

       Addressee:
       Authors:
       Date:
       Format:
       AR No.
Results of Laboratory Testing on Tap Water Taken by Homeowner Near the Davis GSR
Landfill [Confidential].
JOSEPH F. LEMAY - US EPA/REGION I
RICHARD ARSENAULT
June 23, 1993
LETTER
                     03.02.7
                              No. Pgs:   4
                              Document No.
                                                                  000187
       Title:        Davis GSR Landfill, Glocester, RI [Confidential].
       Addressee:    DANIEL GRANZ - US EPA/ENVIRONMENTAL STUDIES SECTION
       Authors:       SCOTT CLIFFORD - US EPA/LEXINGTON LABORATORY
       Date:         August 9, 1993
       Format:        MEMORANDUM                    No. Pgs:   6
       AR No.        03.02.8                       Document No.   000189

       Title:        Davis GSR Landfill—Volatile Organics by GC/MS.
       Addressee:    DAVID S. GRANZ - US EPA/ENVIRONMENTAL STUDIES SECTION
       Authors:       STEVEN HELLER, SURESH SRIVASTAVA, JOSEPH
                     MONTANARO - US EPA/LEXINGTON LABORATORY
       Date:         August 10, 1993
       Format:        MEMORANDUM                    No. Pgs:   26
       AR No.        03.02.9                       Document No.   000188

       Title:        Davis Landfill.
       Addressee:    DANIEL GRANZ - US EPA ENVIRONMENTAL STUDIES SECTION
       Authors:       KATHLEEN M. POLGAR - US EPA/LEXINGTON LABORATORY
       Date:         September 8, 1993
       Format:        MEMORANDUM                    No. Pgs:   3
       AR No.        03.02.10                      Document No.   000190

03.04  REMEDIAL INVESTIGATION - INTERIM DELIVERABLES

       Title:        Health and Safety Plan, Davis GSR Landfill.
       Addressee:    JOSEPH F. LEMAY - US EPA/REGION I
       Authors:       CDM/FEDERAL PROGRAMS CORPORATION
       Date:         November 1990
       Format:        LETTER                        No. Pgs:   25
       AR No.        03.04.1                       Document No.   000153
       Title:

       Addressee:
       Authors:
       Date:
       Format:
       AR No.
Davis GSR Landfill, Glocester/Smithfield, Rhode Island, Ecological Characterization,
Summary Report.
JOSEPH F. LEMAY - US EPA/REGION I
CDM/FEDERAL PROGRAMS CORPORATION
February 1992
LETTER
                     03.04.2
                              No. Pgs:   121
                              Document No.   000156
       Title:        Davis GSR Landfill Site, Sampling and Analysis Plan/Quality Assurance Project Plan.
       Addressee:    JOSEPH F. LEMAY - US EPA/REGION I
       Authors:       CDM/FEDERAL PROGRAMS CORPORATION
       Date:         March 1992
       Format:        LETTER                        No. Pgs:   24
       AR No.        03.04.3                       Document No.   000157
       Title:        Task 3.6: Phase I Surface Water/Sediment Analysis.
       Addressee:    JOSEPH F. LEMAY - US EPA/REGION I
       Authors:       CDM/FEDERAL PROGRAMS CORPORATION
       Date:         October 7, 1992
       Format:        LETTER                        No. Pgs:   5
       AR No.        03.04.4                       Document No.   000158

-------
       Title:         Report on Geophysical Investigations at the Davis GSR Landfill, Smithfield Rhode
                     Island.
       Addressee:     CDM/FEDERAL PROGRAMS CORPORATION
       Authors:       CASWELL EICHLER & HILL,  INC.
       Date:          December 1992
       Format:        REPORT, STUDY                 No. Pgs:    134
       AR No.         03.04.5                       Document No.   000138

       Title:         Addendum to Sampling Analysis Plan/Quality Assurance Project Plan, March 1992 with
                     Summary Responses April 1992.
       Addressee:     NADINE RANIERE - US EPA/REGION I
       Authors:       CDM/FEDERAL PROGRAMS CORPORATION
       Date:          January 15, 1993
       Format:        LETTER                        No. Pgs:    3
       AR No.
                     03.04.6
                                                   Document No.
                                                                  000159
       Title:

       Addressee:
       Authors:
       Date:
       Format:
       AR No.
Addendum to Sampling Analysis Plan/Quality Assurance Project Plan, March 1992 with
Summary Responses April 1992.
NADINE RANIERE - US EPA/REGION I
CDM/FEDERAL PROGRAMS CORPORATION
March 26,
LETTER
          1993
                              No. Pgs:
                                         8
                     03.04.07
                                                   Document No .
                                                                  000144
       Title:         Davis GSR Landfill, Trip Report for Phase II Monitoring Well Installation, Soil
                     Boring and Well Development.
       Addressee:     US EPA/REGION I
       Authors:       CDM/FEDERAL PROGRAMS CORPORATION
       Date:          April 7,  1993
       Format:        REPORT,  STUDY                 No. Pgs:   52
       AR No.         03.04.8                        Document No.   000145

       Title:         Davis GSR,  Standard Operating Procedure, Sediment Filtration to Achieve Adeguate
                     Percent  Solids.
       Authors:       CDM/FEDERAL PROGRAMS CORPORATION
       Date:          June 1994
       Format:        REPORT,  STUDY                 No. Pgs:   8
       AR No.         03.04.9                        Document No.   000162

03.06  REMEDIAL INVESTIGATION - REMEDIAL INVESTIGATION REPORTS

       Title:         Davis GSR Landfill Glocester/Smithfield, Rhode Island, Final Remedial Investigation
                     Report,  Vol. I
       Addressee:     US EPA/REGION I
       Authors:       CDM/FEDERAL PROGRAMS CORPORATION
       Date:          November 1994
       Format:        REPORT,  STUDY                 No. Pgs:   952
       AR No.         03.06.1                        Document No.   000146
       Title:

       Addressee:
       Authors:
       Date:
       Format:
       AR No.
Davis GSR Landfill Glocester/Smithfield, Rhode Island, Final Remedial Investigation
Report, Vol. II Appendices A-F.
US EPA/REGION I
CDM/FEDERAL PROGRAMS CORPORATION
November 1994
REPORT, STUDY
                              No. Pgs:
                                         983
                     03.06.2
                                                   Document No.
                                                                  000147
       Title:         Davis GSR Landfill Glocester/Smithfield, Rhode Island, Final Remedial Investigation
                     Report,  Vol. Ill Appendices G-I.
       Addressee:     US EPA/REGION I
       Authors:       CDM/FEDERAL PROGRAMS CORPORATION
       Date:          November 1994
       Format:        REPORT,  STUDY                  No. Pgs:   472
       AR No.         03.06.3                        Document No.   000148

-------
       Title:         Remedial Investigation Report Addendum--Modified Risk Assessment Tables—Davis GSR
                     Landfill,  Glocester/Smithfield, Rhode Island.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       MATTHEW DENTCH - CDM/FEDERAL PROGRAMS CORPORATION
       Date:          March 20,  1997
       Format:        LETTER                         No. Pgs:   25
       AR No.         03.06.4                        Document No.   000163

03.07  REMEDIAL INVESTIGATION - WORK PLANS AND PROGRESS REPORTS

       Title:         Davis GSR Landfill,  Glocester/Smithfield, Rhode Island, Remedial
                     Investigation/Feasibility Study, Revised Work Plan, Vol. I—Technical Scope of Work.
       Addressee:     US EPA/REGION I
       Authors:       RI DEPT OF ENV MGMNT/SOLID WASTE MGMNT
       Date;          July 1991
       Format:        REPORT, STUDY                  No. Pgs:   150
       AR No.         03.07.1                        Document No.   000164

03.09  REMEDIAL INVESTIGATION - HEALTH ASSESSMENTS

       Title:         Preliminary Health Assessment for Davis GSR Landfill, Glocester, Glocester County,
                     Rhode Island, RID980731459.
       Authors:       US PUBLIC HEALTH SERVICE/ATSDR
       Date:          April 10,  1989
       Format:        REPORT, STUDY                  No. Pgs:   4
       AR No.         03.09.1                        Document No.   000165

04.09  FEASIBILITY STUDY - PROPOSED PLANS FOR SELECTED REMEDIAL ACTION

       Title:         Proposed Plan for the Davis GSR Landfill Superfund Site.
       Authors:       US EPA/REGION I
       Date:          June 1997
       Format:        REPORT, STUDY                  No. Pgs:   9
       AR No.         04.09.1                        Document No.   000191

05.03  RECORD OF DECISION - RESPONSIVENESS SUMMARIES

       Title:         Comments on the Proposed Plan for the Davis GSR Landfill Superfund Site.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       JOSEPH V.  SOUZA, MAUREEN SOUZA
       Format:        FORM                           No. Pgs:   2
       AR No.         05.03.1                        Document No.   000202

       Title:         Comments on the Proposed Plan for the Davis GSR Landfill Superfund Site.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       MATTHEW D. DESTEFANO - RI DEM/OFFICE OF WASTE MANAGEMENT
       Date:          July 3, 1997
       Format:        LETTER                         No. Pgs:   5
       AR No.         05.03.2                        Document No.   000194

       Title:         Comments of the Proposed Plan for the Davis GSR Landfill Superfund Site.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       WAYNE FARRINGTON
       Date:          July 16, 1997
       Format:        LETTER                         No. Pgs:   2
       AR No.         05.03.3                        Document No.   000195

       Title:         Resolution of the Glocester Town Council Reguesting US EPA to Continue Yearly
                     Monitoring of Test Wells for the Next Ten Years.
       Authors:       TOWN OF GLOCESTER
       Date:          July 17, 1997
       Format:        PUBLIC MEETING RECORDS         No. Pgs:   1
       AR No.         05.03.4                        Document No.   000196

-------
       Title:         Comments on the Proposed Plan for the Davis GSR Landfill Superfund Site.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       CAROL A. AYALA
       Date:          July 19, 1997
       Format:        LETTER                         No.  Pgs:    3
       AR No.         05.03.5                        Document No.   000197

       Title:         Request for an Extension of Time to Review US EPA's No Further Action Recommendation
                     in Its Proposed Plan for the Davis  GSR Landfill.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       JEFFREY H.  MINOR - SMITHFIELD TOWN  OF
       Date:          July 21, 1997
       Format:        LETTER                         No.  Pgs:    1
       AR No.         05.03.6                        Document No.   000198

       Title:         Transmittal of Copies of the Extended Comment Period Notice and Proposed Plan for
                     the Davis GSR Landfill.
       Addressee:     PAUL CAVANAUGH
       Authors:       SARAH WHITE - US EPA/ OFFICE OF COMMUNITY
                     RELATIONS
       Date:          July 22, 1997
       Format:        LETTER                         No.  Pgs:    1
       AR No.         05.03.7                        Document No.   000199

       Title:         Denial of Request for a Six-Month Extension of the Public Comment Period on the
                     Proposed Plan for the Davis GSR Landfill.
       Addressee:     RICHARD POIRIER - SMITHFIELD TOWN COUNCIL
       Authors:       ANNA KRASKO - US EPA/REGION I
       Date:          July 23, 1997
       Format:        LETTER                         No.  Pgs:    2
       AR No.         05.03.8                        Document No.   000200

       Title:         Comments on the Proposed Plan for the Davis GSR Landfill Superfund Site.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       HENRY E. HATCHER
       Date:          July 24, 1997
       Format:        FORM                           No.  Pgs:    1
       AR No.         05.03.9                        Document No.   000201

       Title:         Comments on the Proposed Plan for the Davis GSR Landfill Superfund Site.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       TERI ROZZERO
       Date:          August 20,  1997
       Format:        LETTER                         No.  Pgs:    1
       AR No.         05.03.10                       Document No.   000204

       Title:         Comments on the Proposed Plan for the Davis GSR Landfill Superfund Site.
       Addressee:     ANNA KRASKO - US EPA/REGION I
       Authors:       HARVEY LIEBERMAN
       Date:          August 21,  1997
       Format:        LETTER                         No.  Pgs:    2
       AR No.         05.03.11                       Document No.   000205

05.04  RECORD OF DECISION - RECORD OF DECISION
       Title:         Record of Decision,  Davis GSR Landfill Superfund Site.
       Authors:       US EPA/REGION I
       Date:          September 29,  1997
       Format:        REPORT,  STUDY
       AR No.         05.04.1                         Document No.    000206

-------
13.02  COMMUNITY RELATIONS - COMMUNITY RELATIONS PLANS

       Title:        Community Relations Plan, Davis Glocester-Smithfield Regional  (GSR) Landfill
                     Superfund Site, Glocester and Smithfield, Rhode Island.
       Addressee:    CDM/FEDERAL PROGRAMS CORPORATION
       Authors:       BARRY LAWSON ASSOCIATES, INC.
       Date:          November 1991
       Format:        REPORT, STUDY                  No. Pgs:    22
       AR No.        13.02.1                        Document No.   000166

13.04  COMMUNITY RELATIONS - PUBLIC MEETINGS

       Title:        Community Meeting Summary,  Davis GSR Landfill Superfund Site, Smithfield, Rhode
                     Island.
       Addressee:    US EPA/REGION I
       Authors:       BARRY LAWSON ASSOCIATES, INC.
       Date:          March 9, 1992
       Format:        REPORT, STUDY                  No. Pgs:    26
       AR No.        13.04.1                        Document No.   000167


       Title:        Public Hearing In Re: Davis GSR Landfill Superfund Site, July 15, 1997.
       Date:          July 15, 1997
       Format:        PUBLIC MEETING RECORDS         No. Pgs:    26
       AR No.        13.04.2                        Document No.   000193

13.05  COMMUNITY RELATIONS - FACT SHEETS

       Title:        EPA Announces No Risks at the Davis GSR Landfill Superfund Site.
       Authors:       US EPA/REGION I
       Date:          June 16, 1997
       Format:        FACT SHEET, PRESS RELEASE      No. Pgs:    2
       AR No.        13.05.1                        Document No.   000192

16.01  NATURAL RESOURCE TRUSTEE - CORRESPONDENCE

       Title:        Acknowledgment of US EPA Trustee Notification for the Davis GSR Landfill Superfund
                     Site.
       Addressee:    GORDON E BECKETT - US EPA/WASTE MANAGEMENT DIVISION
       Authors:       DAVID J NEWTON - US DEPARTMENT OF INTERIOR.
       Date:          July 21, 1987
       Format:        LETTER                         No. Pgs:    1
       AR No.        16.01.1                        Document No.   000168

16.04  NATURAL RESOURCE TRUSTEE - TRUSTEE NOTIFICATION FORM AND SELECTION GU

       Title:        Notification of Potential Damages to Natural Resources from the Davis GSR Landfill
                     Site.
       Addressee:    WILLIAM PATTERSON - US DEPARTMENT OF INTERIOR
       Authors:       MERRILL S HOHMAN - US EPA/WASTE MANAGEMENT DIVISION
       Date:          June 8, 1987
       Format:        LETTER                         No. Pgs:    6
       AR No.        16.04.1                        Document No.   000169

17.04  SITE MANAGEMENT RECORDS - SITE PHOTOGRAPHS/MAPS

       Title:        Site Analysis, Davis Solid Waste Disposal, Glocester, Rhode Island  [Available in EPA
                     Records Center].
       Date:          August 1985
       Format:        PHOTO, MICROFILM, VIDEO        No. Pgs:    31
       AR No.        17.04.1                        Document No.   000170

       Title:        Site Analysis, Davis GSR Landfill, Glocester, Rhode Island, Volume I  [Available in
                     EPA Records Center].
       Date:          October 1990
       Format:        PHOTO, MICROFORM, VIDEO        No. Pgs:    23
       AR No.        17.04.2                        Document No.   000171

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                             Guidance Documents

EPA guidance documents may be reviewed at EPA-New England Records Center, Boston, Massachusetts.

1.   Interim Guidance on Superfund Selection of Remedy, U.S. Environmental Protection Agency, Office of
     Solid Waste and Emergency Response. (OSWER Directive 9355.0-19). December  26, 1986.

2.   Interim Guidance on Potentially Responsible Party Participation in Remedial Investigations and
     Feasibility Studies, U.S. Environmental Protection Agency.  (OSWER Directive 9835.la).  May 1988.

3.   Community Relations in Superfund:  A Handbook (Interim Version) U.S. Environmental Protection Agency
     Office of Emergency and Remedial Response  (EPA/540/G-88/002),  June 1988.

4.   Guidance for Conducting Remedial Investigations and Feasibility Studies Under CERCLA,  (Comprehensive
     Environmental Response, Compensation,  and Liability Act), U.S. Environmental Protection Agency,
     Office of Emergency and Remedial Response. (EPA/540/C-89/004)   (9355.3-01) October 1988.

5.   Risk Assessment Guidance for Superfund, Volume II, Environmental Evaluation Manual,
     (EPA/540/1-89/001)  March 1, 1989.

6.   Procedures for Completion and Deletion of National Priorities List Site , U.S. Environmental
     Protection Agency,  Office of Emergency and Remedial Response.   (EPA/540/G-89/002)(9320.2-3A), April
     1989.

7.   U.S. EPA Region I Supplemental Risk Assessment Guidance for the Superfund Program Part 1:  Public
     Health Risk Assessment and Part 2: Ecological Risk Assessment,  (Comprehensive Environmental
     Response, Compensation, and Liability Act) (EPA/901/5/89-001). June 1989.

8.   Interim Final Guidance on Preparing Superfund Decision Documents, U.S. Environmental Protection
     Agency, Office of Emergency and Remedial Response. (9355.3-02). July 1989.

9.   Risk Assessment Guidance for Superfund, Volume I, Human Health Evaluation Manual,  (OSWER 9285-7-01).
     September 29, 1989.

10.  Risk Assessment Guidance for Superfund, Volume I: Human Health Evaluation Manual (Part A), Interim
     Final  (EPA/540/1/-89-002).  December 1989.

11.  Guidance for Data Usability in Risk Assessment,  Interim Final,  (EPA/540/G-90/008).  October 1990.

12.  Conducting Remedial Investigations/Feasibility Studies for CERCLA Municipal Landfill Sites, U.S.
     Environmental Protection Agency, Office of Emergency and Remedial Response.   (EPA/540/P-91/001).
     February 1991.

13.  Guide to Developing Superfund No Action, Interim Action, and Contingency Remedy RODs, U.S.
     Environmental Protection Agency, Office of Solid Waste and Emergency Response. (OSWER Directive
     9355.3-02FS-3) April 1991.

14.  Memorandum from Don R. Clay, Assistant Administrator, U.S. Environmental Protection Agency Office of
     Solid Waste and Emergency Response to Directors, Waste Management Division, Regions I,  IV, V, VII,
     VIII; Directors, Hazardous Waste Management Division, Regions III, VI, IX; Director, Hazardous Waste
     Division, Region X  (OSWER Directive 9355.0-30),  April 22, 1991,  (discussing the role of the baseline
     risk assessment in Superfund remedy selection decisions).

15.  Memorandum from Henry L. Longest II, Director, U.S. Environmental Protection Agency, Office of
     Emergency and Remedial Response, to Addressees.   (OSWER Directive 9355.7-02).  May 23, 199.

16.  Presumptive Remedy for CERCLA Municipal Landfill Sites, U.S. Environmental Protective Agency, Office
     of Solid Waste and Emergency Response.  (EPA/540/F/93/035) (GR01-1-3). September 1993.

17.  Update to the Procedures for Completion and Deletion of National Priorities List Sites Guidance
     Document Regarding the Performance of Five-Year Reviews. Memo from Henry L. Longest II and Bruce
     Diamond to Director, Waste Management Division,  Regions I, IV, V, VII and VIII.  (OSWER Directive
     9320.2-3B)

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                                       APPENDIX B
                                  TABIiES AND FIGURES

                   TABLE B-l: SUMMARY OF CONTAMINANTS
                 OF CONCERN IN OFF-LANDFILL GROUNDTCATER

                               Maximum
Contaminants                   Concentration       Frequency of
of Concern                      (mg/1)              Detection
benzene                        0.0089              5/17
1,2,4-trimethylbenzene         0.0016              3/17
1,3,5-trimethylbenzene         0.003               1/17
arsenic                        0.0299              5/17
barium                         0.658               13/17
beryllium                      0.0013              4/17
chromium                       0.167               1/17
lead                           0.0173              2/17
manganese                      4.28                16/17
nickel                         0.127               6/17
                   TABLE B-2: SUMMARY OF CONTAMINANTS
                      OF CONCERN IN SURFACE WATER

                               Maximum
Contaminants                   Concentration        Frequency of
of Concern                      (mg/1)               Detection
antimony                       0.06                 2/31
arsenic                        0.0119               1/31
barium                         0.544                31/31
beryllium                      0.005                1/31
lead                           0.171                18/31
manganese                      6.46                 31/31
vanadium                       0.0682               3/31

                   TABLE B-3: SUMMARY OF CONTAMINANTS
                         OF CONCERN IN SEDIMENT

                               Maximum
Contaminants                   Concentration        Frequency of
of Concern                      (mg/kg)              Detection
benzo(a)anthracene             0.083                3/18
benzo(a)pyrene                 0.3                  5/18
benzo(b)fluoranthene           0.19                 4/18
benzo(k)fluoranthene           0.2                  4/18
chrysene                       0.095                3/18
indeno(l,2,3-cd)pyrene         0.024                1/18
antimony                       23.3                 6/18
arsenic                        31.4                 13/18
beryllium                      4.7                  16/18
manganese                      15,600               18/18
thallium                       14                   3/18
vanadium                       60.4                 16/18

                   TABLE B-4: SUMMARY OF CONTAMINANTS
                     OF CONCERN IN AQUEOUS LEACHATE

                               Maximum
Contaminants                   Concentration        Frequency of
of Concern                      (mg/L)               Detection
antimony                       0.0136               ^>
arsenic                        0.0036               2/2
barium                         0.758                2/2
lead                           0.0191               2/2
manganese                      1.69                 2/2
nickel                         0.098                2/2

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                   TABLE B-5: SUMMARY OF CONTAMINANTS
                      OF CONCERN IN LEACHATE SOIL
                               Maximum
Contaminants                   Concentration        Frequency of
of Concern                     (mg/kg)              Detection
aroclor 1248                   0.045                2/18
antimony                       2.5                  1/18
arsenic                        7                    7/18
barium                         293                  18/18
beryllium                      0.61                 15/18
manganese                      1680                 18/18
vanadium                       12.4                 18/18
zinc                           165                  12/18

                   TABLE B-6: SUMMARY OF CONTAMINANTS
                      OF CONCERN IN SURFICIAL SOIL

                               Maximum
Contaminants                   Concentration        Frequency of
of Concern                     (mg/kg)              Detection
benzo(a)anthracene             0.076                2/20
benzo(a)pyrene                 0.064                1/20
benzo(b)fluoranthene           0.086                2/20
benzo(k)fluoranthene           0.063                1/20
chrysene                       0.074                1/20
aroclor 1254                   0.052                4/20
arcolor 1260                   0.31                 2/20
arsenic                        3.9                  2/20
barium                         57.6                 20/20
beryllium                      0.85                 12/18
cadmium                        0.79                 3/18
manganese                      656                  20/20
mercury                        0.19                 7/20
nickel                         10.9                 19/20
thallium                       0.36                 1/20
vanadium                       21.8                 20/20
zinc                           800                  18/20

                   TABLE B-7: SUMMARY OF CONTAMINANTS
                       OF CONCERN IN BORING SOILS

                               Maximum
Contaminants                   Concentration        Frequency of
of Concern                     (mg/kg)              Detection
benzo(a)anthracene              30                  2/48
benzo(a)pyrene                  21                  4/48
benzo(b)fluoranthene            17                  4/48
benzo(k)fluoranthene            22                  4/48
bis(2-ethylhexyl)phthalate      120                 17/47
chrysene                        29                  2/48
fluoranthene                    98                  5/48
fluorene                        80                  5/48
phenanthrene                    150                 7/48
pyrene                          73                  4/48
indeno(l,2,3-cd)pyrene          10                  1/48
dieldrin                        0.22                2/48
aroclor-1254                    1.6                 3/48
antimony                        5.4                 2/43
arsenic                         14.3                33/45
barium                          545                 41/46
manganese                       593                 45/46
nickel                          242                 30/46
selenium                        12.5                6/45
silver                          12.3                7/42
vanadium                        29.2                35/46
zinc                            1280                30/46

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                   TABLE B-8: SUMMARY OF CONTAMINANTS
                   OF CONCERN IN ON-SITE LANDFILL GAS

                                Max. Modeled
Contaminants                    Ambient Cone.       Frequency of
of Concern                       (mg/m-3)             Detection
benzene                         4.3E-04             2/4
dichlorodifluoromethane         2.5E-05             1/4
1,2-dichloropropane             2.3E-05             1/4
1,4-dichlorobenzene             8.3E-05             1/4
ethylbenzene                    5.1E-04             4/4
methylene chloride              1.8E-05             1/4
tetrachloroethylene             3.4E-05             1/4
toluene                         5E-05               4/4
1,1,1-trichloroethane           2.8E-05             1/4
trichloroethylene               2.7E-05             1/4
vinyl chloride                  2E-03               3/4

                   TABIiE B-9: SUMMARY OF CONTAMINANTS
                   OF CONCERN IN OFF-SITE LANDFILL GAS

                                Max. Modeled
Contaminants                    Ambient Cone.       Frequency of
of Concern                       (mg/m-3)             Detection
benzene                         2.01E-05            2/4
dichlorodifluoromethane         1.7E-07             1/4
1,2-dichloropropane             1.63E-07            1/4
1,4-dichlorobenzene             3.9E-06             1/4
ethylbenzene                    2.37E-05            4/4
methylene chloride              1.22E-07            1/4
tetrachloroethylene             2.39E-07            1/4
toluene                         1.40E-06            4/4
trichloroethylene               1.89E-07            1/4
vinyl chloride                  1.87E-06            3/4

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                                           Table B-10
                                                                                                                                                                  Page 1  of 2
                                       DAVIS GSR LANDFILL
                              SUMMARY OF RISKS AND HAZARD INDICES

 REASONABLE MAXIMUM EXPOSURE          AVERAGE CASE MEDIA       TARGET ORGAN                      TARGET ORGAN EXPOSURE POINT
                              RECEPTOR     EXPOSURE PATHWAY     RISK   HAZARD INDEX  HI > 1.0    RISK   HAZARD INDEX   HI  > 1.0
Groundwater
Off-Landfill
   Overburden
  Future Resident     Ingestion
      (Adult)
                                                           3.0E-04     5.5
                                                                                 CNS=4.1     9.9E-05
                                                                                 Skin=1.2
                                                                                                          1.2
   Bedrock
  Future Resident     Ingestion
      (Adult)
Sediments
   Landfill Area B  Current Trespasser    Ingestion
                           (Child)
                                                           5.5E-04     8.1
Surface Water
   Landfill Area B  Current Trespasser    Ingestion
                           (Child)       Dermal Contact

   Off-Landfill     Current Trespasser    Ingestion        7.9E-07
                           (Child)       Dermal Contact     3.1E-08
                                       8.0E-07     0.02
                                                                                 CNS=5.1     1.4E-04
                                                                                 Skin=2.7
                                                                                                          2 . 7     CNS=2.0
0.02
0.0005
0.06
0.0022
—
—
1.5E-07
5.8E-09
0.012
0.0009
0.014
0.0005
                                                                         5.7E-07     0.015
   Off-Landfill     Current Trespasser    Ingestion
                           (Child)
                                       5.3E-06     0.48
                                                                         1.8E-06     0.073
Leachate
   Landfill Area A
   Aqueous          Current Trespasser  Dermal Contact     4.3E-09    0.0006
                           (Child)
                                                                         4.3E-09    0.0006
   Soil
Current Trespasser    Ingestion
      (Child)        Dermal Contact
                                                           9.5E-07     0.051
                                                           8.2E-09
3.2E-07     0.016
4.9E-09

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                                      Table B-10   (cont'd)
Page 2 of 2
                                       DAVIS GSR LANDFILL
                              SUMMARY OF RISKS AND HAZARD INDICES
                                                             REASONABLE MAXIMUM EXPOSURE
AVERAGE CASE MEDIA











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                                                        APPENDIX C

                                            RIDEM DECLARATION OF CONCURRENCE


26 September 1997

Mr. Harley Laing, Director
Office of Site Remediation & Restoration
U.S. Environmental Protection Agency - New England
John F. Kennedy Federal Building, Mailcode: HIO
Boston, MA 02203

RE:  Record of Decision for the Davis GSR Landfill Superfund Site,
     Glocester/Smithfield, Rhode Island

Dear Mr. Laing,

The Department of Environmental Management (DEM) has completed its review of the Record of Decision  (ROD)
for the Davis GSR Landfill Superfund Site. The Environmental Protection Agency's (EPA's) selected
alternative for the site, as presented in the document, is a No Action decision.

DEM has worked on this site with your Agency from the early investigatory stages up through this current
decision milestone. Based upon our review of this ROD and the results of remedial investigation
activities conducted to date, we offer our concurrence on the decision. However, based upon our knowledge
of the site operator's waste disposal practices at the Davis Liguid Waste Superfund Site, we do so with
some reservation. As you are well aware, Mr.  William Davis permitted the dumping of thousands of gallons
of liguid hazardous waste at the Davis Liguid Waste site and currently, your Agency is overseeing the
removal action of thousands of drums containing hazardous wastes. These drums were only recently
discovered while implementing the remedial action for the site and were not expected.

Certainly, you can appreciate our concern, as well as the concern of the local communities, for the
potential unknowns associated with the Davis GSR Landfill. We have no assurances that the Davis GSR
Landfill does not have its own "surprises" similar to those discovered many years later at the Davis
Liguid site. Thankfully,  all of the monitoring to date indicates that there is no significant source of
contamination.

DEM recognizes that CERCLA does not allow for remedial actions based merely upon unknowns and hearsay,
however, we are reguesting that EPA remain ready to respond at this site in the event that future
monitoring indicates a concern.

The Department wishes to specifically emphasize the following aspects of the Record of Decision:

•      Monitoring:

      Monitoring is the critical component of this No Action decision. It is the only line of
      defense provided for in the ROD to protect the local population from unexpected
      occurrences at the site. EPA and DEM must work together with the local community to design
      a plan that provides appropriate protection. Such a plan must also include domestic well
      monitoring. Also, while the ROD states that at least five years of monitoring will be
      conducted, DEM strongly reguests that EPA commit to longer duration.

      EPA and DEM will review the monitoring data on an annual basis. Regular monitoring and
      review are necessary to evaluate the long-term effectiveness of the remedy and to ensure
      the continued protection of human health. If this data reveals that there are escalating
      risks at the Site,  then we both must reevaluate the need to conduct additional monitoring
      and/or other remedial actions at the Site.

•      Five-Year Review:

      The ROD states that no statutory five-year review will be undertaken. DEM did not concur
      with this language and reguested that EPA commit to conducting a five-year review. Your
      Agency has since committed to conducting a five-year review and consider further
      monitoring if necessary. While we recognize that CERCLA does not reguire such a review
      as part of a No Action decision, such a review is not prohibited and is the prudent choice
      with this site and its uncertainties.

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Page Two
H. Laing
26 September 1997

•      Community Relations:

      Community participation is extremely important to DEM and is reguired under
      CERCLA/SARA. During the course of our investigations at this site and, in particular,
      during the Proposed Plan and ROD phases,  there seemed to be poor communication,  or lack
      thereof,  between EPA and the local citizens. EPA awarded a Technical Assistance Grant
      (TAG)  to the local community for participation in this site and the Davis Liguid Waste
      Site,  however,  the TAG never seemed to be involved in this site.

      DEM believes that there is still a role for the TAG in the activities at this site and we
      encourage EPA to attempt to keep them involved. We believe that their participation in the
      development of a site monitoring plan along with the actual review of the data would be
      extremely beneficial.  By providing them with access to the data, they will know firsthand
      about the performance of the remedy and there will be no illusion that we are not
      providing them with all the facts. They can also provide us with real-time information
      regarding changing site conditions, site access concerns and development issues which might affect
      the risk to human health and the environment.

Finally, as mentioned in the ROD, this No Action decision does not limit the State's ability to carry out
any actions under State authority. For this reason, we have reguested that EPA provide us with
information gathered as a result of its Potential Responsible Party (PRP) search. In the event that DEM
finds it necessary to pursue action under State authority, such information would be valuable in aiding
our action.

DEM looks forward to working with EPA in developing and implementing a monitoring plan for
the Site in a timely manner.

Sincerely,




cc:  Andrew McLeod,  Director, RIDEM
     John DeVillars,  Regional Administrator, USEPA
     Edward Szymanski, DEM,  Associate Director
     Paul Fogarty, Town Council President, Glocester
     Jeffrey Minor,  Town Administrator, Smithfield
     Terrence Gray,  DEM, Office of Waste Management
     Claude Cote, Esguire,  DEM, Office of Legal Services

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                       DAVIS GSR LANDFILL SUPERFUND SITE

                                   APPENDIX D

                              RESPONSIVENESS SUMMARY

                                TABLE OF CONTENTS

Section                                                              Page

A.   Introduction	1

B.   The No Action Alternative	1


C.   Overview of Community Involvement and Concerns	2

     Community Background	2
     History of Community Involvement and Concerns	2

D.   Summary of Public Comments Received During Public Comment Period and
Agency Responses	3

     Residents, and Local and State Officials' Comments	3

Attachment 1
Community Relations Activities at the Davis GSR Landfill Site
     Chronology of Community Relation Activities

Attachment 2
Transcript of the July 15,  1997 Public Hearing

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RESPONSIVENESS SUMMARY                                                    Page 1
Davis GSR Landfill Site

A.   Introduction

The U.S. Environmental Protection Agency  (EPA) held a 60-day public comment period from June 24, 1997 to
August 22, 1997 to provide an opportunity for interested parties to comment on the Remedial Investigation
and the Proposed Plan prepared for the Davis Glocester-Smithfield Regional  (GSR)  Landfill Superfund Site
in Glocester/Smithfield, Rhode Island. In the Proposed Plan issued on June 16, 1997, EPA announced a
preference for No Action, other than limited monitoring, at the site. A collection of all documents used
by EPA in choosing this alternative were made available for review at the EPA Records Center (90 Canal
Street, Boston, MA) and at the E. Smithfield Public Library (50 Esmond Street, Smithfield, Rhode Island).
These documents are known collectively as the Administrative Record.

The purpose of this Responsiveness Summary is to document EPA's responses to the comments and guestions
raised during the public comment period. The comments submitted during the public comment period are
available in the Administrative Record for the Davis GSR Landfill  Site. EPA considered all of the
comments before making a final decision not to take further action under CERCLA at this site.

B.   The No Action Alternative

A No Action preferred alternative is being selected by EPA due to the low potential for adverse
ecological and human health risks estimated in the baseline risk assessment. The estimated cancer risk
associated with exposure to contamination at the Site falls within EPA's acceptable risk range. Cancer
risks at a Superfund Site are considered acceptable if a probability of adverse health effects occurring,
ranges between ten thousand and one million (10 -4 to 10 -6).  All current and future risks attributable
to exposures associated with inhalation of landfill gas, and ingestion of, or contact with, the surficial
soils, surface water and sediment are below the lower end of the acceptable risk range (i.e., 10 -6). No
current health risks are associated with exposure to groundwater at the Site, since the contaminated
groundwater is not being used for drinking water. No plume of contamination was found emanating from the
landfill. The risk of groundwater ingestion as a drinking water source was estimated at the upper end of
the acceptable risk range (i.e., 10 -4) attributable largely to the presence of arsenic,  which is
present, however, at levels below those established as safe in the Safe Drinking Water Act.

The hazard index was calculated by EPA as a measure of the potential for non-carcinogenic health effects.
The human health risk assessment concluded that non-cancer adverse health effects were unlikely at this
Site. The elevated levels of manganese, the main contributor to the future potential noncarcinogenic
hazard index of 8.4, were only detected in an wetland area along the periphery of the landfill. This
hazard index may present a level of concern for a human health drinking water scenario, assuming that
groundwater at this location is ingested as a sole source of drinking water. This is a very conservative
estimate of future exposure, however, as this location is immediately adjacent to the landfill. Exposure
to groundwater as a drinking water source in this limited area is unlikely due to the steep slopes and
proximity to the wetlands which would preclude development.

Results of the ecological risk assessment indicates that, although contaminants have been found in the
sediments and surface waters near the landfill, it is unlikely that a reduction in viable wetland habitat
would adversely impact any flora and fauna populations. Results of a conservative food chain modeling
also indicated no adverse effects.

EPA has included five years of additional groundwater monitoring under CERCLA authority in the No Action
alternative. Groundwater monitoring, including residential well monitoring, will be performed to verify
that no unacceptable exposures occur in the future. The scope and freguency of the monitoring will be
adjusted as necessary, based on the sampling results.

C.     Overview of Community Involvement and Concerns

Community Background

The Davis GSR and Landfill Superfund Site is located in a rural residential area. Houses are widely
separated, and woods, wetlands, and occasional open fields dominate the rolling landscape around the
Site.

The Site itself is located in two towns, Smithfield and Glocester, with a majority located in the latter.
The Town of Smithfield consists of five villages: Esmond, Georgiaville, Spragueville, Greenville, and
Stillwater. The primary governmental body is the Town Council, whose five members are elected every two
years. Glocester is a town of three villages:  Chepachet, Harmony, and West Glocester. The town government

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in Glocester is run by a town council with five members who are elected for two-year terms.

History of Community Involvement and Concerns

Community residents have been involved with both Davis GSR Landfill and the nearby Davis Liquid sites for
over 15 years. Residents have attended public meetings and filed complaints on the sites'  operation by
Mr. Davis with local, state, and federal officials. Some members of the community have opposed the Davis
GSR Landfill since it first open. The Waterman Lake Conservation Association opposed the opening of the
landfill because of their concern that it would contaminate Waterman Reservoir,  a lake used primarily for
recreational purposes,  about two miles downstream from the Site.

Judging from the comments received during the public comment period, the residents and the local and
State offices generally agree with the no action decision, but there is a considerable concern regarding
a potential for future migration of contaminants and a preference for continuing monitoring of
groundwater.

The level of community activity has significantly subsided since the early 1980s. Some local officials
and residents are concerned with the expense and the time required to assess and cleanup the sites.

D.   Summary of Public Comments Received During Public Comment Period and Agency Responses

This Responsiveness Summary addresses comments received by EPA during the public comment period (June 24,
1997 through August 22,  1997).

Residents, and Local and State Officials' Comments

One set of comments was received from the State (Rhode Island Department of Environmental management) and
oral and written comments were received from the local officials (Town of Smithfield and Town of
Glocester). Both oral and written comments were received from residents leaving near the Davis GSR
Landfill Site.

Comment 1: Local officials and the State expressed concern about health, safety, and welfare of the
residents surrounding the area and felt that EPA should continue to monitor the groundwater on an annual
basis for an extended period of time (i.e., 10 years)  and to provide the test results to the town. Local
officials also felt that additional assurances for the regular monitoring, such as monitoring plan needs
to be in place.

EPA's response: Extensive data collected by EPA during implementation of the Remedial Investigation  (RI)
in the early 1990s and the residential well testing program conducted by RIDOH in the area since the
early 1980s found no contaminated groundwater plume emanating from the site or site-related contamination
in any of the residential wells. No elevated levels of site-related contaminants were detected in
residential bedrock wells east and southeast of the landfill which, based on observed local bedrock flow
patterns, is downgradient. As such, the observed concentrations of manganese near the toe of the landfill
in bedrock appear to have been sufficiently diluted or dispersed by traveling approximately 2,000 feet
downgradient which equates to approximately 4 years of travel time based on the hydrogeological
parameters of the fractured bedrock system, where retardation of contaminants is minimal.  Thus, since
this municipal waste landfill ceased accepting waste in 1982, no changes in groundwater quality are
expected in a future.

The EPA's decision that no further action be done at this landfill under CERCLA is issued because the
Baseline human health and ecological risk assessment concluded that the site poses no unacceptable risk
or threat to human health or the environment and that CERCLA is not an appropriate mechanism to handle
this municipal solid waste landfill. As documented in this Record of Decision, EPA and the State will
continue limited monitoring of the groundwater, including residential wells, for at least five years
under CERCLA authority,  to verify that no unacceptable exposures occur. The testing frequency and
parameters are expected to be adjusted as necessary based n the monitoring results. Following the
issuance of this Record of Decision, a monitoring plan will be jointly developed by EPA and the State.
Based on the data available at this Site, EPA believes that this is a conservative monitoring approach
which will provide additional assurances to the residents on the quality of the groundwater leaving the
site. Given substantial amount of time lapsed since the landfill stopped accepting the waste in 1982 and
the data showing low level of contaminants at this solid waste landfill, EPA believes that such future
unacceptable exposures are very unlikely and that 5 years of monitoring under CERCLA would be a
conservative approach to provide sufficient level of confidence. Furthermore, the State's authority to
handle the closure of this municipal solid waste landfill, including any monitoring programs, is in no
way limited by this No Action Record of Decision Some further monitoring beyond the five years, may be
required in a future to satisfy State's requirements.

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All monitoring results will be available for public review at the E. Smithfield Public Library on 50
Esmond Street, Smithfield, RI, and the EPA's Record Center on 90 Canal Street in Boston, MA.. The town
officials can be notified of the results when these are available and copies of the monitoring results
can be provided to the town council.

Comment 2: Several residents and local officials commented on the groundwater monitoring, including
residential well testing. They felt that the testing of their residential wells has not been done
regularly in the recent past and stated that testing of monitoring and residential wells should continue
on some prescribed basis.

EPA's response: Residential well monitoring was initiated by the Rhode Island Department of Health
(RIDOH) in the early 1980s, in response to the residents' concerns, when little data existed about the
extent of contamination associated with this Landfill. Since then, 32 monitoring wells have been
installed and sampled and extensive data has been collected on the soil,  groundwater, surface water and
sediment guality at and adjacent to the landfill. No increases in contaminant levels were detected over
time and no contaminant plume was found to be emanating from the landfill, and the low levels of
contaminants present were found to pose no unacceptable risk to human health or the environment.
Approximately 20 residential wells in the area have also been monitored by EPA and the RIDOH for more
than 10 years and none were found to be contaminated. Based upon the data available at this time, EPA and
the State are planning to monitor groundwater, including residential wells for at least five years under
the CERCLA authority to verify that no unacceptable exposure occurs in the future. The results of this
monitoring will be public information.

Additionally, it should be noted that Federal and State laws do not regulate private water supplies. As
in any other areas of the State, the residents drinking water from their own wells, are responsible for
making sure it is safe to drink. While the residents are not reguired to do so by law, RIDOH strongly
recommends that these residents test their water annually for a few of the more common contaminants.
RIDOH provides guidance on home water testing parameters and freguency, including special situations like
wells located near a dump, landfill, or an industrial operation, as well as testing services available in
the State.

Comment 3: Some residents and local officials stated that the Site should continue remain on the National
Priority List  (NPL),  due to the uncertainty of what may be buried in the landfill. They felt it would
provide additional assurance that the landfill would be monitored properly and actions would be taken if
new findings indicate that additional response actions are warranted.

EPA's Response: Since the landfill ceased the operation in 1982, EPA performed extensive site
characterization and collected significant amount of data, which indicates that the type and levels of
contaminants found at the Davis GSR Landfill are typical of what would be expected at a municipal solid
waste landfill and that no contaminant plume is emanating from the Site.  The decision to continue the
groundwater monitoring, including monitoring of residential wells, as documented in this Record of
Decision, will not be affected by the deletion of the Site from the NPL.  Furthermore, deletion of a site
from the NPL does not preclude eligibility for subseguent remedial action. Section 300.66(c)(8)of the
National Contingency Plan  (NCP) states that Fund-financed response may be taken at sites that have been
deleted from the NPL if future conditions warrant such actions without returning the site to NPL. If it
is determined that the site should be returned to the NPL due to a threat to human health or the
environment, it may be reinstated without re-scoring on the Hazard Ranking System  (HRS). The deletion of
the Site from the National Priority List (NPL) will include publication of the Notice of Intent to Delete
and 30-day public comment period. EPA will accept and evaluate public comments before making a final
decision to delete.

Comment 4: The State felt that EPA should assist the "Dump the Dump" local citizens group in the
community participation process and the President of this Group expressed disappointment with low turnout
at the public meetings concerning the Site and felt that EPA should assist the group in contacting the
new residents in the area and providing them with information on the landfill. One commenter also felt
that the residents should be given funding to retain a technical advisor to review the information
pertaining to the site.

EPA's Response: EPA agrees that strong community participation is desirable in the Superfund process. EPA
also feels that it has been responsive to community needs at this project and provided the assistance
reguested by the local citizens. Below is chronology of the Technical Assistance Grant  (TAG) for the
local "Dump the Dump" group, documenting EPA's assistance efforts.

12/04/91  Rec'd Letter-of-Intent from F. Monroe Allen, Dump the Dump, to apply for the Technical
          Assistance Grant

01/01/92  Public Notice published Providence Journal

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02/10/92  Ltr to F. Monroe Allen stating that no other group has expressed interest in applying for the
          TAG, and Dump the Dump has 30 days to apply

02/27/92  Rec'd Itr from F. Monroe Allen reguesting a 30 day extension to the application period

02/27/92  Telephoned F. Monroe Allen to grant the extension and offer any assistance necessary

06/22/92  Rec'd application for TAG from Dump the Dump

09/18/92  M. McGagh met with R. Poirier to get signatures on the final documents necessary to process the
          TAG

09/23/92  T.G awarded  ($50,000)

09/08/93  Ltr to R. Poirier reguesting the status of the grant since EPA had not heard from the group
          since the TAG was awarded

Summer'95 Focus Group Mtng: G. Nearney acknowledged that the group had problems, but they had been
          resolved and TAG activities should pick up.

10/03/95  Ltr to R. Poirier referring to a telephone message of 10/02/95, and a conversation of 10/03/95
          regarding the future of the TAG.

          Enclosed in that letter were completed applications for an extension of the grant to be signed
          and returned to EPA for processing.

12/13/95  Ltr to R. Poirier following-up on the 10/03/95 Itr

CY96      Numerous voice mail between 0. Beverly of EPA and R. Poirier, Dump the Dump

01/29/97  Ltr from R. Poirier reguesting that the TAG be reactivated and EPA's assistance to that end.

Spring 97 Numerous voice mail between 0. Beverly, M. McGagh of EPA and R. Poirier, Dump the Dump

07/10/97  Telephone call to R. Poirier, he is currently on vacation until August of 1997, and will call
          me when he returns.

07/15/97  At the reguest from P. Cavanough, extended public comment period on the Proposed Plan from its
          original closing date of July 23, 1997 to August 22, 1997 (reguest for six-month extension from
          the Councilman P. Poirier was denied based on the reasons outlined in EPA's July 23, 1997
          letter).

07/21/97  Telephone call to P. Cavanough to determine the status of the Dump the Dump group, left
          message.

July 1997 Correspondence with P. Cavanough and transmittal of additional copies of the informational
          documents on an effort to provide information on Davis GSR Landfill to new residents and
          include them on the EPA' s mailing list

Thus, no activities or expenditures under the TAG grant for both Davis GSR and Davis Liguid sites have
occurred since 1992. Although the October, 1995 application prepared by EPA for an extension of the grant
was never signed by the TAG group, EPA is currently in a process of determining the current status of the
group and their contact person. EPA is working with the local residents to extend the grant, which at
this point can be used to strengthen participation of this group at the Davis Liguid Superfund Site.

Comment 5: The State reguested clarifications on the exposure assumptions used in performing the Baseline
Risk Assessment.

EPA's response: The final baseline human health risk assessment has been completed to include all current
and potential future exposure scenarios to chemical hazards posed by the Site. The final report includes
conservative risk assessment estimates assuming that trespassing children would be exposed to current
site conditions (i.e., uncapped) such as exposure to landfill surficial soils, leachate, and landfill
gas, while playing or wading at the site. All current and future risks attributable to these exposures
were below the lower end of the acceptable risk range (i.e., 10 -6) or below a hazard index of 1, in most
cases by several orders of magnitude. Estimated maximum cancer risks to human health associated with use
of off-landfill groundwater as potential future drinking water source fall within EPA's acceptable risk
range. In addition, EPA concluded that non-cancer adverse health effects were not likely at this site.

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The evaluated future exposure scenarios did not include exposures to contaminated groundwater under the
landfill or exposure to contaminants within the landfill since EPA believes that such exposures will not
occur due to land use restrictions already in place under the State and local laws and regulations under
any future cleanup scenario, including no action decision under CERCLA.

In response    to this concern raised during the State's review of the draft Proposed Plan, the final
Proposed Plan included the following definition of the Baseline Human Health Risk Assessment under the
Glossary of Environmental Terms: "An assessment of the likelihood that people living, working, or playing
at or near a Superfund site could experience health problems as a result of their contact with chemicals
from the site,  assuming no remediation."

Similarly, additional data has been collected and supplemental calculations were performed for the
ecological baseline risk assessment, leading to a conclusion that current conditions at the site do not
present an unacceptable risk to the ecological receptor populations.

Comment 6: The State asked for clarifications on public release of the draft Feasibility Study report

EPA's response. Upon review of the revised Feasibility Study prepared by the contractor, EPA concluded
that the second draft contains significant number of inconsistencies and incorrect assumptions and
analyses, including analysis of the ARARs and No Action alternative, which would reguire substantial
rewriting of the Feasibility Study. As a policy, draft documents are not typically released to the
public, as they may not provide accurate reflection of the Agency's position on a number of issues. EPA
believes that significant additional expenditures and time would be reguired to produce a final FS which
could be approved by EPA and released to the public. Such expenditures are not warranted since the
proposed decision for no further action at the Davis GSR Landfill site is based on the baseline risk
assessment conducted during the RI. That risk assessment supports the determination that no remedial
action is necessary to ensure protection of human health and the environment. This Record of Decision
provides a summary of site risks explaining the basis for EPA's conclusion that unacceptable exposures to
hazardous substances will not occur. Although in this case, work on the Feasibility Study was started
prior to completion of the baseline risk assessment, remedial alternatives in the FS are generally not
developed for No Action RODs.  No Action decisions do not include description of alternatives or
comparative analysis of such alternatives because no remedial action is necessary.

Comment 7: One commenter felt that EPA's risk assessment largely focused on the possible human exposures,
while ecological impact was not less explored

EPA's Response: EPA performed extensive ecological investigations and baseline ecological risk assessment
at the Davis GSR landfill to assess the ecological conseguences of the landfill contamination, including
assessment of wetland function and values, characterization of habitat and flora and fauna utilizing the
area, identification of potential receptors and exposure pathways, performance of site-specific toxicity
testing, macroinvertebrates study, and food-chain exposure modeling (see Sections 11 and 12 of the
Remedial Investigation report).  As summarized in this Record of Decision, risks to benthic and
terrestrial invertebrates, aguatic biota, and wildlife were gualitatively and guantatively assessed.
Results of the ecological risk assessment indicated that no unacceptable risks to ecological receptors is
likely to occur at this site and therefore, did not suggest a need for response action.

Comment 8:  One commenter suggested that EPA formally notify the Audubon Society, which owns land
adjacent to the site, the future users of the contiguous property on Tarkiln Road, and the local
governments of Smithfield and Glocester that trespassing on the site should be strictly prohibited and
asked that a no trespassing policy be established in conjunction with the land owner and be aggressively
enforced.

EPA's Response: The baseline human health risk assessment conducted by EPA predicts no adverse health
impacts would occur to children who may trespass and wade in the wetlands or have skin contact with
contaminants in surface water, sediment, surficial soil on the landfill, and agueous and soil leachate,
and who may breath landfill gas. The assumed exposure doses for the reasonable maximum exposure point
concentrations included 0.05 liters of water ingested per hour for 1 hour per day, 2,000 cm 2 skin
surface area for contact per event for 1 event/day, 200 mg of sediment and soil ingested per day with
100% adsorption, and 0.83 m 3 of air inhaled per hour for two hours per day of exposure, all for 36 days
per year for 12 years in a 70 year lifetime by a 43 kg child. All current and future risks attributable
to these exposures were below the lower end of the acceptable risk range (i.e., 10 -6) or below  a hazard
index of 1, in most cases by several orders of magnitude. Thus, even if the site in the future is more
accessible, the increased freguency of exposure would not pose unacceptable risk to human health. As
such, the baseline human health risk assessment does not provide a technical basis for EPA to establish
any restrictive trespassing policies for this site.

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The local town officials,  the Audubon Society and home owners living in a vicinity of the site are on the
EPA's mailing list and are notified of this Record of Decision being issued.  This Record of Decision,
along with other documents,  is available for public review at the E. Smithfield Public Library on 50
Esmond Street in Smithfield,  RI.  This Record of Decision under EPA's CERCLA authority,  however,  does not
limit in any way the local or State's authority and is not a determination that no action is warranted
under other laws and regulations  to regulate this former solid waste landfill,  including access
restrictions.

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Attachment 1
Community Relations Activities at the Davis GSR Landfill Site

Davis GSR Superfund Site
Chronology of Community Relation Activities
June 1986-

November 1990-

December 1990-

May 1991-

November 1991-

November 1991-
November 1991-

December 1991

January 1992-

1991-1994-

May 1997-

June 1997-

June 1997-

June 1997-

June 1997-
                  Davis GSR Landfill listed on the Superfund National Priorities List

                  Information Repository established Greenville and Harmony Public Libraries

                  Press release announcing start of Remedial Investigation (RI)  issued

                  EPA conducts community interviews with local officials and residents

                  EPA Community Relations Plan made available to public

                  Press release issued announcing EPA RI underway at Davis GSR public is invited to
                  attend meeting.
                  Fact sheet on remedial investigations issued

                  Community meeting held to discuss remedial investigations

                  "Dump the Dump" awarded Technical Assistance Grant (TAG)

                  EPA conducts Remedial Investigation at Davis GSR

                  Repository relocated to E.  Smithfield library

                  EPA issues notice on RI results and no action proposed plan

                  EPA issues a press release announcing proposed plan and meetings

                  EPA mails out proposed plan to community

                  EPA hold public meeting to discuss results of RI

June-August 1997- 60-day public comment period

June 1997-        Administrative Record placed at E. Smithfield Library

July 1997-        EPA holds formal public hearing to accept comment on the proposed plan

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Attachment 2
Transcript of the July  15,  1997  Public  Hearing
1

2

3
                          ENVIRONMENTAL PROTECTION AGENCY
4
                               REGION I -  NEW ENGLAND
5

6

7
            PUBLIC HEARING  IN  RE:
9

10
           DAVIS GSR LANDFILL  SUPERFUND  SITE
11

12

13
                                     JULY 15,  1997
14                                   7:00 P.M.
15
                                     SMITHFIELD TOWN HALL
16                                   SMITHFIELD,  RI
17

18

19
          BEFORE:
20

21
                     RICHARD BOYNTON
22
                     ANNA KRASKO

23                   SARAH  WHITE

24

                       ORIGINAL

                  A-l COURT REPORTERS, INC.
                     (401) 231-E

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1                       (COMMENCED AT 7:07 P.  M.)

2            MR.  BOYNTON:  My name is Richard

3   Boynton of the New England EPA office located

4   in Boston and I'11 serve as the Hearing

5   Officer for tonight's  hearing on the Davis GSR

6   site located in Glocester and Smithfield

7   proposed plan. Also here with me tonight are

8   Anna Krasko,  the EPA project manager for the

9   site and Sarah White,  EPA's community

10  relations specialist.

11        The purpose of tonight's hearing is  to

12   formally accept oral  comments on the Davis GSR

13   proposed plan which was released on June  22nd

14   and was described as  a public meeting held at

15   this location on June 23rd. Public comment

16   period began on June  24th and will end on July

17   23rd.     Anna will give a brief overview of the

18   plan and then I'll open the meeting for oral

19   comments.

20        If you would like to make an oral

21   comment, please state your name and

22   affiliation because we are going to be

23   recording the proceedings for the

24   responsiveness summary which we will put
                 A-l COURT REPORTERS,  INC.
                       (401)  231-E

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1   together after the comment period closes.

2        Are there -- well,  Anna,  would you please

3   give a brief overview of the plan?

4         MS. KRASKO: Thank you, Dick. As

5   Dick just mentioned,  last month EPA announced

6   the proposed plan for actions for the Davis

7   GSR landfill superfund site. In its plan EPA

8   recommended that no further cleanup under

9   CERCLA be done at this site because the low

10   levels of contaminants present do not pose an

11   unacceptable threat to human health or the

12   environment.

13        Before arriving at this conclusion EPA

14   conducted an extensive study of the extent and

15   nature of contamination at the Davis GSR

16   landfill superfund site and determined that

17   the potential for adverse ecological and human

18   health risks from this site is unlikely. EPA

19   proposed, however, that monitoring of the

20   groundwater, including residential well

21   monitoring, be continued to verify that no

22   unacceptable exposures occur in the future.

23        The state supports EPA' s recommendation

24   that no remedial action at the site is
                  A-l COURT REPORTERS,  INC.
                      (401) 231-E

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1   warranted and that monitoring be continued.

2   The proposal by EPA not to pursue further

3   action at this site is not a determination

4   that no action is warranted under other

5   regulations or statutes.  It simply means that

6   EPA has determined that the CERCLA cleanup

7   authority is not the appropriate mechanism to

8   handle the closure of this municipal waste

9   landfill. Some actions may be required in the

10  future to satisfy requirements of the

11  pertinent state laws. Thank you.

12        MR. BOYNTON: Thank you, Anna. Is

13  there anybody here who would like to make an

14  oral comment?

15        MR. KAVANAUGH: I would like to go

16  on record as indicating —

17        MR. BOYNTON: Your name please.

18        MR. KAVANAUGH: My name is Paul

19  Kavanaugh. I live at 251 Log Road in

20  Smithfield and I am the President of Dump to

21  Dump. And I would like to go on record first

22  indicating my presence, and secondly, as a

23  request for a continuation of the comment

24  period because I think that the indications
              A-l COURT REPORTERS,  INC.
                   (401)  231-E

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1   first off is the fact that the poor turn out

2   tonight is indication to me of the fact that

3   the -- a number of the residents in that area,

4   and there has been a considerable amount of

5   construction within maybe a mile of that site,

6   that they probably don't even have knowledge

7   of the GSR landfill. And I would like to be

8   able to or our organization would like to be

9   able to contact those people so that in fact

10  they can be informed about the location of the

11  GSR landfill and be able to have their

12  comments included into any public hearing, any

13  public record before a final decision can be

14  made.

15        MR. BOYNTON: For those of you who

16  just arrived late, we opened the hearing and

17  we are hearing oral comments. If you would

18  like to make oral comments just give your

19  name,  your address and you can have your oral

20  comments put in the record by our court

21  reporter. If not, you can submit written

22  comments at the address that's in our proposed

23  plan and those will be entered into the record

24  as well.  Does anyone else want to make an
              A-l COURT REPORTERS,  INC.
                   (401)  231-E

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1   oral comment? Mr. Benick?

2        MR. BENICK: I don't know if it's in

3   the nature of a comment. Is it appropriate to

4   ask a question?

5        MR. BOYNTON: After I close the

6   formal part of the hearing I'11 open it for

7   informal questions and then we can have some

8   dialoq on how we did what we did.

9        MR. BENICK: Okay.

10      MR. BOYNTON: Mr. Kavanauqh has

11  asked that we extend the comment period, so

12  I'm qoinq to make a decision riqht now to

13  extend the comment period for an additional 30

14  days beyond the July 23rd date which was --

15  we'll keep the record open for that additional

16  time. Yes, sir?

17        MR, FOGARTY: Paul Foqarty,

18  President of the Glocester Town Council. I

19  was at the last meeting that you had here

20  about three weeks ago and I'm just here again

21  to, you know, express my concerns over being

22  taken off the list. It sounds all nice and

23  everything, but I'm just very leery of it in

24  that there's no plan on testing these wells
              A-l COURT REPORTERS,  INC.
                 (401)  231-8860

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1   and they haven't been tested,  was it,  since

2   1994 they haven't been tested, so you are

3   talking three years now and I  don't think

4   there is any plans to retest them and no one

5   knows what is buried up there  and with the

6   superfund having all the money and the state

7   having no money, you know,  I wanted to be --

8   our Council meeting is Thursday     night and we

9   have a resolution we are going to act upon

10  stating this and we'll forward it to you, but

11  we are just very leery of being taken off the

12  — for both Smithfield and Glocester,  the

13  superfund. They are the ones with all the

14  dollars to do everything. And  just having the

15  testing is a big thing, it would make the

16  people, you know, like no one  knows what is up

17  there. It is buried. Barrels or whatever, it,

18  could be barrels that could corrode a while,

19  you know, five years from now  and who knows

20  what's in them and with all the water there,

21  Nine Foot Lake, Waterman's Lake is not that

22  far away. Anything could happen. It would be

23  a catastrophe up there and we  strongly feel

24  that the government should submit some sort of
             A-l COURT REPORTERS,  INC.
                (401)  231-8860

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1   plan or whatever that they are still going to

2   monitor this and that they will assume any

3   responsibility if something comes up.

4        MR. BOYNTON: Are there any other

5   comments for the record?  If not, I'll close

6   the hearing, formal part of the hearing and

7   then open it for general guestions.

8        We'll be making a decision after the

9   close of the comment period and tonight I

10  extended the comment period for an additional

11  30 days. Originally it was to close on July

12  23rd, so I extended it and did we make a

13  public announce of that?

14        MS. WHITE: Yes, we will.

15       MR. BOYNTON: We'll do another press

16  release.

17        MS. WHITE: To everybody on the

18  mailing list and I'll try to get the

19  additional names from new comers.

20        MR. BOYNTON: That will keep the

21  record open for an additional 30 days after

22  July 23rd, so if you want to put in written

23  comments, you can send them to the address

24  that's in our proposed plan and we welcome all
              A-l COURT REPORTERS,  INC.
                  (401)231-8860

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1   your comments and after the comment period

2   closes,  we'll take all this information under

3   consideration and we'll make a decision on

4   what we are going to do there which will

5   include how we are going to handle some

6   monitoring and we probably expect to issue

7   that in the fall I would think. Thanks for

8   coming.

9                 (FORMAL MEETING ADJOURNED)

10

11

12

13           CERTIFICATE

14

15        I hereby certify that the foregoing is a

16  true and accurate transcript of the hearing

17  taken before Region I, New England EPA, on

18  July 15, 1997, at 7:00 p.m.

19

20

21  

22

23

24
                  A-l COURT REPORTERS, INC.
                       (401)  231-E

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1

2

3                 ENVIRONMENTAL PROTECTION AGENCY

4                     REGION I NEW ENGLAND

5

6            PUBLIC HEARING IN RE:

7

8            DAVIS GSR LANDFILL SUPERFUND SITE

9

10

11

12                                      JULY  15, 1997
                                        7:00  P.M.
13

14                                     SMITHFIELD  TOWN HALL
                                        SMITHFIELD,  RI
15

16

17

18           BEFORE:

19

20                       RICHARD BOYNTON

21                       ANNA KRASKO

22                       SARAH WHITE

23

24                       ORIGINAL
                 A-l COURT REPORTERS,  INC.
                        (401) 231-E

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1   MR.  BOYNTON:  Let me just respond to,

2   Councilman Fogarty's question.  We intend to

3   transfer some money to the state to do some

4   monitoring at the site.  We haven't decided

5   what the frequency is, what the progress will

6   be,  but we do intend to transfer some money to

7   the state to do some monitoring. Even though

8   the site is delisted, we still  can do that.

9   Even though we take a site off  the superfund

10  list we can still spend-superfund money for

11  that. We intend to do that. We  just haven't

12  come up with a monitoring plan. We haven't

13  decided what we are going to do.

14        MR. KAVANAUGH: What is the purpose

15  of removing a   site from the superfund list?

16  Is it a bookkeeping issue?

17        MR. BOYNTON: Well, it's not a

18  bookkeeping issue. It just that there is no

19  contamination there that would  warrant a

20  superfund action. It doesn't exceed any of

21  our acceptable risk parameters  for -- there is

22  no cause for us to use the superfund there.

23  So it's no longer necessary to  remain on the

24  list. We can still respond to a release just
               A-l COURT REPORTERS,  INC.
                   (401) 231-E

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1   as it were a site across the street here

2   which was not on the list.  If there is

3   release,  we can respond. So being on the list

4   is or off the list doesn't  mean you can't

5   respond to a release at the site.

6        MR.  KAVANAUGH:  But it  is slow.

7       MR. BOYNTON: No. No. Actually it

8   is faster. If we have a release at a site,  we

9   respond immediately if it's an emergency

10  situation. So we can always put it back on

11  the list.

12        MR. KAVANAUGH: But to detect that

13  emergency might be easier if in fact it is on

14  the list?

15        MR. BOYNTON: It will  be no

16  different. The monitoring program at the site

17  would be based upon what we found in the past

18  and what we believe is there and over the

19  years we haven't found anything.

20        MR. KAVANAUGH: Okay.  But there are

21  two parts of what you just  said. One is what

22  we have found there and what we believe is

23  there.

24        Mr. BOYNTON:   I don't believe there
               A-l COURT REPORTERS,  INC.
                    (401)  231-E

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1   is anything left there personally after

2   looking at all the data over the years and

3   looking at all the interviews and all of the

4   information that we got from all the companies

5   that we sent out reguests for information to.

6   I don't believe there's any hidden ticking

7   time bomb at that site.

8        MR. KAVANAUGH:  My level of comfort

9   in that response might rise if it were a

10  single site, not associated with the activity

11  that was going on across the site a few

12  hundred yards away and run by the same

13  individual.

14        MR. BOYNTON: We never found any

15  evidence or any — we never got any

16  information from anybody that was -- that we

17  could rely that was factual that he was, and I

18  assume you are referring to Mr. Davis, was

19  putting waste over there.

20        MR. KAVANAUGH:  But there was a lot,

21  of nighttime activity which starts to indicate

22  that maybe anyone who would record such

23  activity wouldn't be forthcoming certainly to

24  EPA or to anyone else as to what went on.
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 1              MR.  BOYNTON:   The monitoring data

 2         didn't show it.

 3              MR.  KAVANAUGH:   So far it doesn't.

 4              MR.  BOYNTON:   No. I mean, it's been

 5         20 years.  I just don't believe it's there.

 6         of all the sites that I've looked at,  and you

 7         know, usually you can see something.  The

 8         level of contamination at this site is so Low

 9         that I just can't believe there's anything

10         there.  I mean,  it's just -- it's even lower

11         than some municipal solid waste landfills in

12         Rhode Island.  I mean level of contamination.

13               MR. FOGARTY:  Let's suppose ten

14         years from now they find something radically

15         wrong. This is just a -- what happens then?

16         Who is going to take over?

17               MR. BOYNTON:  There is a response by

18         EPA and the state to that release.

19               MR. FOGARTY:  Will the superfund

20         pick it right up?

21               MR. BOYNTON:  If there is a release

22         at that site at any time that causes a

23         hazardous situation, both state and    EPA will

24         respond.   If they find something in    the
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 1         groundwater that indicates there's been a

 2         release,  then they'll respond in some fashion

 3         even though it's not on the superfund list.

 4         It doesn't have to be on the superfund list.

 5         There's many sites that aren't that we respond

 6         to.

 7               MR. FOGARTY:  What is the normal

 8         monitoring period, other sites that have been

 9         off the List?  How often do they get

10         monitored?

11               MR. BOYNTON:  Annual. If you've

12         been monitoring the site for years and you've

13         found no changes,  say,  even monthly or

14         guarterly, you go to semiannually and you find

15         no changes, then you go to annually and you

16         find no changes and you find a decline, then

17         you set up your monitoring program for that.

18         You wouldn't expect to see a change.

19               MR. FOGARTY:  Why hasn't it been

20         tested since 1994?

21               MR. BOYNTON:  We didn't see any

22         reason to do it at that time.  The data showed

23         very little contamination.

24               MR. FOGARTY:  Before '94 when was
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 1         the last test?

 2               MS.  KRASKO:   '94 and '92.

 3               MR.  BOYNTON:   When we were doing the

 4         investigation and when we found no problems

 5         there naturally we kind of put the site on the

 6         back burner because we had more important

 7         contamination until finally somebody said

 8         let's wrap this site up.

 9               MR.  FOGARTY:   There is 22 wells?

10               MR.  BOYNTON:   I don't know off   the

11         top of my head how many wells there are.

12               MR.  FOGARTY:   What's the cost to

13         monitor it per year?

14               MR.  BOYNTON:   Maybe 40,000,  50,000

15         if you did annually.   If there's 22 wells and

16         you did a full sweep on each well, it has to

17         be a couple thousand dollars a well, right?

18         So I mean, it is a very expensive proposition

19         but I don't think we monitored it for all the

20         parameters.  I mean,  we didn't find any -- we

21         found one VOC in any -- that had any freguency

22         in our wells  and that was benzine and it was

23         much below the mcl.  And then all the rest of

24         the stuff was inorganics, manganese and
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 1         arsenic which we expect to find were the high

 2         ones.

 3               MR. FOGARTY:  I think the main

 4         concern Glocester has is that when you pull

 5         the circuits out of town and leave we don't

 6         want to be left and -- we want to make sure

 7         there is something to fall back on.

 8               MR. BOYNTON:  When we write our

 9         decision we'll say what we are going to do in

10         terms of monitoring.  I don't know what we'll

11         say, probably the freguency of monitoring and

12         how we are going to do it which will be

13         transfer money to the state to do it. I would

14         want the state to do it.  It is a solid waste

15         landfill.  It should be regulated by the state

16         and I want the state to oversee it, look at

17         it, monitor it and make decisions on it.  I

18         mean,  it still comes under the solid waste

19         rules of the  state.  And those rules and

20         wetlands rules, all of those things should be

21         regulated.  It shouldn't be regulated on the

22         superfund I believe.  I don't think it should

23         be.

24               MR. FOGARTY:  My problem, you know
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 1          how the state is,  they are always bogged

 2          down.

 3               MR. BOYNTON:   I'll give them money

 4          now to do work.  We give them money now to do

 5          work on sites.  So -- and each year they give

 6          me an application and tell me what they are

 7          going to do with the money that I give them,

 8          so that's the kind of thing where they come in

 9          and say what kind of monitoring they are going

10          to do, how much, and I would say that is worth

11          x and I would transfer the money.

12               MR. FOGARTY:   I feel if so much

13          money, you say $40,000 to monitor every year,

14          if that was allotted, that would make us feel

15          a lot more comfortable knowing that, that that

16          doesn't have to come from the state.  I'm just

17          worried, you put it on the state, it gets lost

18          and there's always --

19               MR. BOYNTON:   It can't get lost if I

20          give it to them because they have to report on

21          the financial status report back to the EPA.

22          It comes like in a grant.

23               MR. FOGARTY:   If you have to rely on

24          the state to do it, the $40,000 is going to
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 1         get cut.

 2               MR. BOYNTON:  I don't have any

 3         control over what they do with their money,

 4         but the money that we funnel through to them

 5         we get reports on it, financial status reports

 6         what they are doing for the money.

 7               MR. BOYNTON:  More questions?

 8         Rick?

 9               MR. BENICK:  I was just curious. I

10         applaud your approach to this site.  I think

11         it is an over responsible and realistic

12         approach.  I was just curious.  I tried to go

13         through some of the data and I couldn't

14         confirm whether were there any parameters

15         which exceeded any mcl or any arr in the

16         groundwater at all.

17               MS. KRASKO:  There was benzine and

18         arsenic exceeded the level, but it was still

19         below mcl so it was well within the range.

20         Benzine was found at about six parts per

21         billion or eight parts per billion, mcl of five,

22         and it was acceptable.

23               MR. BENICK:  So was the approach as

24         kind of the risk assessment approach where you
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 1         assess the risk and determine,  properly so in

 2         my view,  that there was no view to --

 3               MS. KRASKO:  No action was taken

 4         based on what -- it was based on the base

 5         line, base line risk assessment.

 6               MR. BOYNTON:  We detected benzine

 7         three out of six samples and the maximum, the

 8         only one that exceeded the mcl  was 8.9 parts

 9         per billion, so we had one exceedance which is

10         really for practical purposes is really

11         not an exceedance when you are  talking about

12         five versus   ten parts per billion.  I mean --

13               MS. KRASKO:  The main point was not

14         just the level but where the contaminants were

15         detected and the detections, still very

16         low, were right along the perimeter of the

17         landfill and the wetlands length itself, where

18         potential for exposure was minimal.

19               MR. BOYNTON:  I took a look at --

20         for the median concentration which is the

21         concentration in the middle, the publication

22         put out by Ken Eddy Sciences for solid waste

23         landfills and the median concentration they

24         got for Benzine, 221 parts per  million in the
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 1         groundwater.   That was in the leachate.   And

 2         as I say ours was like nine parts per billion,

 3         so it wasn't anywhere near the kind of range

 4         that you would expect.

 5               MS.  MAINE:   Robin Maine.   How much

 6         has EPA expended to date at the site?

 7               MR.  BOYNTON:  3.8 million.

 8               MS.  MAINE:   Do you know what the

 9         state's figure is on the site or is that a

10         subset of the 3.8?

11               MR.  BOYNTON:  I don't know what

12         their figure  is, but we've passed through

13         money to them to help us with the work which

14         would be included in the 3.8 million and I

15         don't know what their own figures are.  I

16         don't know what the state's figures are.

17               MS.  MAINE:   Are you going to be

18         seeking that money --

19               MR.  BOYNTON:  We haven't decided

20         what we are going to do in terms of recovering

21         that money or if we will try to recover it.

22         We haven't made a decision on that.    Any more

23         guestions?    Yes, ma'am?

24                MS. TETREAULT:  My name is Beth
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 1         Tetreault. I live in Glocester.   The land

 2         adjacent to the Davis GSR landfill has been

 3         willed to the Audubon Society and I was

 4         wondering with people or the public had an

 5         access to the Audubon land,  is there a concern

 6         that the traffic will spill  over onto the

 7         landfill site, and are there any steps being

 8         taken to prevent that traffic from going over

 9         and making -- degrading the  site?

10               MR. BOYNTON:  No,  we haven't done

11         anything like that.   We didn't find any risk

12         to anybody coming in contact with the surface

13         soils or the sediments or the surface at the

14         site itself.

15               MS. TETREAULT:  I'm not so much

16         concerned about contact from the surface soil,

17         but that is a capped landfill, is that

18         correct?

19               MR. BOYNTON:  It has dirt on the top

20         of it and vegetation; it doesn't have a cap so

21         to speak.

22               MS. TETREAULT:  If     you don't stop

23         people having access to the  site, people can

24         go in on dirt bikes  and they could degrade the
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 1         cap that is on that site and then you could

 2         have a possibility of contamination from

 3         whatever is buried there.

 4               MR.  BOYNTON:  We didn't — as I

 5         said,  under superfund we didn't find any risk

 6         or cause to take any action due to people

 7         coming in contact with the surface soils or

 8         the sediments or the surface water at the

 9         site,  so we could not spend superfund money to

10         restrict access to the site because it wasn't

11         necessary.  There is no risk.  The superfund

12         works  from hazardous substances.  It still is

13         regulated by the state and if the state wanted

14         to restrict access to it,  they could.  It

15         still  comes under the regulations of the state

16         solid  waste rules.

17               MS.   TETREAULT:  Do you know if the

18         solid  waste laws have any regulations about

19         restricting --

20               MR.  BOYNTON:  I don't know about

21         that,  whether they reguire restricting access

22         to that site.  I don't think people just

23         wandering on the landfill are at risk from a

24         release.  According to our risk calculations,
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 1         they are not at risk.

 2               MS.  TETREAULT:   Do you have any

 3         figures on how thick the cap is that is on top

 4         of the landfill?

 5               MS.  KRASKO:  Yes.  It varies between

 6         mostly   six to twelve inches over most of the

 7         landfill.

 8               MS.  TETREAULT:   So it's not real

 9         deep.   It could be degraded fairly rapidly

10         with traffic.

11               MR.  BOYNTON:  I don't know.  I don't

12         Know.   It's not —

13               MS.  KRASKO:  The vegetation is very

14         thick.

15               MR.  BOYNTON:  Yes, sir?

16               MR.  GOFF:  John Goff, Glocester Town

17          Council.   Does anybody actually know what's

18          buried there?

19               MR.  BOYNTON:  From     all our

20          investigations mostly municipal industrial

21          solid waste.  We didn't have any indications

22          that there are any hazardous     substances buried

23          there.  There was mostly -- it came from the

24          cities like Providence, some Boston, some
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 1          different haulers.   We did extensive work on

 2          tracking down the state's records.   We

 3          interviewed about 40 or 50 different people

 4          who had — companies who had brought waste

 5          there and we found there is no factual

 6          evidence that any hazardous waste went there,

 7          just commercial/industrial miscellaneous

 8          solids.

 9               MR. GOFF:   There is nothing that

10          could have been snuck in?

11               MR. BOYNTON:  Oh, yeah, but there is

12          nothing indicated in the data that anything

13          went there after 20 years.  I think if there

14          was a release there, if somebody was in there

15          dumping hazardous waste into the groundwater,

16          we would see something and we haven't.  If an

17          occasional drum was thrown in there, it

18          certainly is not showing up in the

19          groundwater, and it's been in there 20 years.

20          I think they stopped dumping there back in

21          '77.

22               MR. GOFF:   Thank you.

23               MR. BOYNTON:  Any more guestions?

24                      (INFORMAL MEETING ADJOURNED)
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 1





 2                         CERTIFICATE





 3





 4               I hereby certify that the foregoing is a




 5          true and accurate transcript of the hearing





 6          taken before Region I New England EPA,  on July





 7          15,  1997,  at 7:00 p.m.





 8




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