EPA Superfund
Record of Decision:
Naval Weapons Station
(O.U. 2), Yorktown, VA
9/29/1995
PB95-963925
EPA/ROD/R03-95/217
May 1996
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Final
Record of Decision
Site 16 and
Site Screening Area 16
(Operable Unit No. II)
Naval Weapons Station Yorktown
Yorktown, Virginia
September 1995
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TABLE OF CONTENTS
Page
LIST OF ACRONYMS AND ABBREVIATIONS iv
DECLARATION FOR THE RECORD OF
DECISION REMEDIAL ALTERNATIVE SELECTION v
Site Name and Location v
Statement of Basis and Purpose v
Description of the Selected Remedy v
Declaration Statement v
DECISION SUMMARY 1-1
1.0 Introduction 1-1
2.0 Site Name, Location and Description 2-1
3.0 Site History and Enforcement Activities 3-1
4.0 Highlights of Community Participation 4-1
5.0 Scope and Role of the Response Action 5-1
6.0 Site Characteristics 6-1
7.0 Summary of Site Risks 7-1
8.0 Description of the No Further Remedial Action Decision with Institutional
Controls 8-1
9.0 Explanation of Significant Changes 9-1
RESPONSIVENESS SUMMARY 10-1
10.1 Background on Community Involvement 10-1
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LIST OF TABLES
7-1 Summary of Contaminants of Potential Concern Evaluated in the
Human Health Risk Assessment
7-2 Summary of Maximum ICR and HI Values Calculated in the Human
Health Risk Assessment
7-3 Summary of Contaminants of Potential Concern Evaluated in the Ecological
Risk Assessment
8-1 Summary of Criteria and Risk-Based Values Applicable to the Groundwater
COPCs
8-2 Summary of Information Used to Evaluate Areas of Concern with Respect to
the Ecological Risk Assessment
LIST OF FIGURES
2-1 Location of Naval Weapons Station Yorktown
2-2 Site Map-Site 16/SSA 16
3-1 Round One RI Sampling Locations
3-2 Removal Action Sampling Locations
3-3 Round Two RI Sampling Locations
3-4 Positive Detections of Organic Compounds in Surface Soil
3-5 Positive Detections of Select Inorganic Analytes in Surface Soil
3-6 Positive Detections of Select Inorganic Analytes in Subsurface Soil
3-7 Positive Detections of Organic Compounds in Groundwater
3-8 Positive Detections of Select Inorganic Analytes in Groundwater
3-9 Positive Detections of Select Inorganic Analytes in Surface Water
3-10 Positive Detections of Organic Compounds in Sediment
3-11 Positive Detections of Select Inorganic Analytes in Sediment
APPENDICES
A Transcript of Public Meeting - August 23,1995
B Response to Comments Received During the Public Comment Period
in
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LIST OF ACRONYMS AND ABBREVIATIONS
ARAR
CERCLA
COPC
DoN
FFA
FS
ffl
ICR
MCL
mg/kg
MI
NCP
NPL
OU
PCBs
PMCL
ppm
PRAP
QI
RCRA
RI
ROD
SSA
SVOC
TNT
USEPA
VOC
WPNSTA
Applicable or Relevant and Appropriate Requirement
Comprehensive Environmental Response, Compensation, and Liability Act
of 1980, as amended, 42 U.S.C. §§9601-9657
contaminant of potential concern
Department of the Navy
Federal Facilities Agreement
Feasibility Study
hazard index
incremental cancer risk
Maximum Contaminant Level
milligram per kilogram
Mobility Index
National Contingency Plan, 40 C.F.R. Part 300
National Priorities List 42 U.S.C. §9605
Operable Unit
polychlorinated biphenyls
Primary Maximum Contaminant Level (Virginia)
parts per million
Proposed Remedial Action Plan 42 U.S.C. §9617
quotient index
Resource Conservation and Recovery Act
Remedial Investigation
Record of Decision 42 U.S.C. §9617
site screening area
semivolatile organic compound
trinitrotoluene
micrograms per kilogram
micrograms per liter
United States Environmental Protection Agency
volatile organic compound
Naval Weapons Station
IV
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DECLARATION FOR THE RECORD OF
DECISION REMEDIAL ALTERNATIVE SELECTION
Site Name and Location
Operable Unit No. II
Site 16 (West Road Landfill) and Site Screening Area 16 (Building 402 Metal Disposal Area and Environs)
Naval Weapons Station Yorktown
Yorktown, Virginia
Statement of Basis and Purpose
This decision document presents a determination that the No Further Remedial Action Decision with Institutional Controls
is sufficient to protect human health and the environment for Operable Unit No. II (OU II), Site 16, the West Road Landfill;
and Site Screening Area (SSA) 16, the Building 402 Metal Disposal Area at the Naval Weapons Station (WPNSTA)
Yorktown (Site 16/SSA 16). This determination has been made in accordance with the Comprehensive Environmental
Response, Compensation, and Liability Act of 1980 as amended (CERCLA) and, to the extent applicable the National
Contingency Plan (NCP). This decision has been based upon documents contained in the administrative record file for
Site 16/SSA 16.
The Department of the Navy (DoN) has obtained concurrence from the Commonwealth of Virginia and the United States
Environmental Protection Agency (USEPA), Region III, on the selected No Further .Remedial Action Decision with
Institutional Controls.
Description of the Selected Remedy *
The selected remedy for Site 16/SSA 16 is the No Further Remedial Action Decision with Institutional Controls.
Site 16/SSA 16 has been designated as OU II. The No Further Remedial Action with Institutional Controls for OU II is
the final action for Site 16/SSA 16. A Removal Action conducted by DoN under 42 U.S.C. § 9604 which included the
removal of identified surficial waste material was conducted in 1994. This previous action mitigated the existing potential
for human health risks and ecological effects associated with the source of contamination.
The selected remedy involves no additional remedial actions to take place at the Site, including long-term monitoring or
sampling. The remedy includes institutional controls, specifically land-use restrictions and aquifer-use restrictions.
Although risk levels at Site 16/SSA 16 under the future child resident scenario are within the generally accepted risk range,
institutional controls have been included as a conservative measure. The land-use restrictions will be established to restrict
future land development of Site 16/SSA 16 area for residential purposes. Aquifer-use restrictions will be implemented to
disallow the placement of potable supply wells within the site area. These institutional controls will be established and
maintained through the WPNSTA Yorktown's Master Plan. The institutional controls will be utilized to insure that future
residential use of the area will be controlled by the DoN. The rationale for selecting this remedy was based on the results
of the Round One and Round Two Remedial Investigations (RIs) for Site 16/SSA 16, baseline human health and ecological
risk assessments, and confirmation sample results from the 1994 Removal Action. The RIs addressed all media at Site
16/SSA 16.
Declaration Statement
No further remedial actions with the exception of institutional controls are necessary at Site 16/SSA 16 to ensure protection
of human health and the environment Contaminant levels detected in the media at Site 16/SSA 16 were found to present
no significant threat to human health or the environment with respect to current exposure scenarios. The institutional
controls included under the selected alternative will ensure the protection of human health and the environment with respect
to future potential exposure scenarios: A five year review under 42 U.S.C. § 962 l(c) will not be required for OU II under
the selected alternative since identified site contaminants of concern, which are present at the Site above health-based
levels, have been determined to be within the concentration range of naturally-occurring background concentrations of
inorganics foynd at, WPNSTA Yor:
£7
__ ___
Signature (Commanding Officer Naval Weapons Station) Date
Thomas C. Voltaggio. Director/ / ) .s' Date
Hazardous Wasre'Managcmeni Divjafon t—-^
USEPA - Reeion III ^^
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tl-H KtU J tlWriL)
DECISION SUMMARY
1.0 Introduction
On October 15,1992 WPNSTA Yorktown was placed on CERCLA's National Priorities List (NPL).
As a result, the DoN has been appointed the lead agency for CERCLA actions at WPNSTA
Yorktown. The USEPA, Region III and the Commonwealth of Virginia also have authority at
WPNSTA Yorktown; however, their roles are as support agencies. The USEPA, Region III, the
Commonwealth of Virginia, and the DoN have recently finalized a Federal Facilities Agreement
(FFA) for WPNSTA Yorktown; The primary purpose of the FFA is to ensure that the environmental
impacts associated with past disposal activities at WPNSTA Yorktown are thoroughly investigated,
and that appropriate CERCLA and Resource Conservation and Recovery Act (RCRA) corrective
action alternatives are developed to protect human health and the environment.
An RI was conducted for the area known as Site 16, the West Road Landfill, and SSA 16, the
Building 402 Metal Disposal Area and Environs (i.e., Site 16/SSA 16). The FS, which normally
follows the RI, was not performed at Site 16/SSA 16, since no unacceptable risk to human health
or the environment was present at the Site under the current and predicted future land use for
WPNSTA Yorktown (i.e., industrial). A Proposed Remedial Action Plan (PRAP) has been prepared
for Site 16/SSA 16 to document the decision for aNo Further Remedial Action Alternative. Based
on comments received from the USEPA Region III, institutional controls have been added to the
selected alternative for Site 16/SSA 16.
A CERCLA remedial action is often divided into Operable Units. As defined in the NCP 40 C.F.R.
§300.5, an "Operable Unit means a discrete action that comprises an incremental step toward
comprehensively addressing site problems. This discrete portion of a remedial response manages
migration or eliminates or mitigates a release, threat of release or pathway of exposure. The cleanup
of a site can be divided into a number of operable units, depending on the complexity of the
problems associated with the site. Operable units may address geographical portions of a site,
specific site problems or initial phases of an action, or may consist of any set of actions performed
over time or any actions that are concurrent but located in different parts of a site."
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MflY-02-1996 13=19 EPA REG 3 HUIMD P. 03/04
This Record of Decision (ROD) for Site 16/SSA 16 as OU II has been prepared to present the
rationale for the No Further Remedial Action Decision with Institutional Controls. This document
is a compilation of key information that may be found in greater detail in the Round Two Remedial
Investigation Report, and in oiher documents contained in the administrative record. The ROD has
been prepared to summarize the remedial alternative selection process. Site 16/SSA 16 have been
designated as OU II. The No Further Remedial Action Decision with Institutional Controls is the
final action for OU II. Other operable units for other WPNSTA Yorktown sites will be defined by
separate investigations.
The selected remedy involves no additional remedial actions to take place at the Site, including long-
term monitoring or sampling. Institutional controls (i.e., land-use restrictions and aquifer-use
restrictions) will be implemented. Monitoring is not required since there are no unacceptable risks
under current scenarios for the environmental media at Site 16/SSA 16. Although risk levels at
Site 16/SSA 16 under the future child resident scenario are within the generally accepted risk range,
institutional controls have been included as a conservative measure.
Land-use restrictions will be established to restrict future land development of the Site 16/SSA 16
area for residential purposes. Aquifer-use restrictions will be implemented to disallow the
placement of potable supply wells within the site area. Although some inorganic constituents in
groundwater exceeded Applicable or Relevant and Appropriate Requirements (ARARs) such as
Maximum Contaminant Levels (MCLs), they did not exceed naturally-occurring background
concentrations of these constituents which also exceeded the MCL concentrations.
The institutional controls will be utilized to insure that future residential use of She 16/SSA 16 will
be controlled by the DoN. These institutional controls will be enforced through the WPNSTA
Yorktown Master Plan. The Master Plan is used to direct and coordinate all base operations. It is
updated periodically.
The rationale for selecting this remedy was based on the results of the Round One and Round Two
RIs for Site 16/SSA 16, baseline human health and ecological risk assessments, and confirmation
sample results from the 1994 Removal Action. The rationale is presented later in this ROD in
Section 8.0.
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J.O- l^f tl-W KtLi ,3 HWnLt P. 04/04
2.0 Site Name. Location and Description
• WPNSTA Yorktown
WPNSTA Yorktown is a 10,624 acre installation located on the Virginia peninsula in York County,
James City County, and the City of Newport News. Figure 2-1 displays the location of WPNSTA
Yorktown. The facility is bounded on the northwest by the Naval Supply Center Cheatham Annex,
the Virginia Emergency Fuel Farm, and the future community of Whittaker's Mill; on the northeast
by the York River and the Colonial National Historic Parkway; on the southwest by Route 143 and
Interstate 64; and on the southeast by Route 238 and the community of Lackey.
WPNSTA Yorktown, originally named the U.S. Mine Depot, was established in 1918 to support the
laying of mines in the North Sea during World War I. The establishment of the depot was the
culmination of a search process, begun in 1917 at the request of Congress, to locate an Atlantic coast
site for weapons handling and storage. For 20 years after World War I, the depot received,
reclaimed, stored, and issued mines, depth charges, and related materials. During World War n, the
facility was expanded to include three additional trinitrotoluene (TNT) loading plants and new
torpedo overhaul facilities. A research and development laboratory for experimentation with high
explosives was established in 1944. In 1947, a quality evaluation laboratory was developed to
monitor special tasks assigned to the facility, which included the design and development of depth
charges and advanced underwater weapons. On August 7, 1959, the U.S. Mine Depot was
redesjgnated the U.S. Naval Weapons Station. Today, the primary mission of WPNSTA, Yorktown
is to provide ordnance, technical support, and related services to sustain the war-fighting capability
of the armed forces.
• Site 16/SSA16
Figure 2-2 presents a site map for both Site 16 and SSA 16. As shown, the majority of SSA 16
overlies the northern portion of Site 16. Subsequently, RI activities addressed Site 16 and SSA 16
at the same time; therefore, the entire area is referred to as Site 16/SSA 16.
Site 16 is an approximately 5-acre area located adjacent to West Road near Lee Road. The northern
portion of the Site is adjacent to a set of railroad tracks and is primarily flat and grass covered. The
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remaining portion of the site is currently wooded. The eastern, southern, and western sides of the
site dip into drainage pathways that run in a southerly direction. Eventually, these drainage
pathways move west into Felgates Creek, which drains into the York River, approximately 1-1/2
miles from the site.
SSA 16 is located between West Road and a set of railroad tracks, west of Building 402. The SSA
encompasses the northern area of Site 16, which is primarily flat and covered with grass and dirt.
ft
With respect to land usage, no housing currently exists at Site 16/SSA 16. SSA 16 was reportedly
used for waste container storage prior to the remodeling and conversion of Building 402 into a
hazardous waste storage facility. The current WPNSTA Yorktown hazardous waste storage facility
is located at Building 2035. Building 53 at the western portion of Site 16/SSA 16 is used for the
Stations' wildlife and forestry management personnel. North of the Site is a horse pasture and
paddock.
With respect to geology and hydrogeology, the Site is underlain by unconsolidated deposits of fine-
grain sand, silts, clays, and marine shells. The Dogue, Pamunky, and the Uchee Soil Association
was observed north of Felgates Creek, throughout the majority of the study area. The soils of this
association are generally found to be deep, moderately to well drained, and to have clayey, silty,
sandy, loams in the surface soils. The subsurface soils are either loamy or clayey. Local
groundwater flow is towards the southwest in the direction of Felgates Creek.
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SECTION 2.0
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FIGURE 2-1
LOCATION OF NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
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SITE 167
SSA 16
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STTEMAP
SITE 16/SSA 16
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3.0 Site History and Enforcement Activities
• Site 16/SSA 16 - History
Site 16 was operated from the 1950's to the early 1960's as a dump site. Wastes reported to have
been disposed include: dry carbon-zinc (Leclanche) batteries, banding materials, pressure
transmitting fluid, unknown types of chemicals, mine casings, construction debris, and 55-galIon
drums (contents unknown). During a waste characterization investigation, most of the waste at
Site 16 was identified as being surficial debris. Mine casings, batteries, drums, scrap metal, and
construction debris were identified in several areas across the surface of the site.
Only one small area containing waste at depth was encountered at Site 16. Located underneath a
pile of drums, this small waste area contained common refuse material including glass, cans, and
newspapers. The refuse material was encountered at a depth of 2 feet below ground surface and
extended to a depth of approximately 9 feet Based on this waste characterization study, this waste
was disposed by filling in the slope edge of the site and then covering it.
SSA 16 was used for scrap metal storage. Dumpsters containing scrap metal had been located on
the lower southwest side of the SSA. Empty drums and scrap metal had been observed on the
ground surface near these dumpsters.
• Previous Investigations
Previous investigations at Site 16/SSA 16 include an Initial Assessment Study, a Confirmation Study
and RI Interim Report, a Biological Sampling and Preliminary Risk Evaluation, a Round One RI,
a Habitat Evaluation, a Removal Action, and a Round Two RI. The results from these studies are
briefly discussed below.
Initial Assessment Study
An Initial Assessment Study was conducted at WPNSTA Yorktown in 1984. The purpose of the
study was to identify and assess sites posing a potential threat to human health and/or the
environment due to contamination from past operations. The study identified 15 sites at WPNSTA
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MPY-02-1996 14 = 22 EPfl REG 3 HWMD
Yorktown, including Site 16, that were of sufficient threat to human health or the environment to
warrant further investigations.
Confirmation Study and RI Interim Report
In 1986 and 1988, two rounds of sampling were conducted for a Confirmation Study at Site 16. The
study was documented in two Confirmation Study reports and a third report known as the RI Interim
Report. The RI Interim Report recommended that further RI activities be conducted at Site 16.
Biological Sampling and Preliminary Risk Evaluation
The Biological Sampling and Preliminary Risk Evaluation, which included the sampling of
biological tissue, surface water, and sediment from select waters within WPNSTA Yorktown, was
conducted in 1992. The primary objective of the sampling program was to evaluate the potential
human health risk associated with consumption offish and shellfish taken from select water within
the Station.
Round One RI
The Round One RI for Site 16/SSA 16, conducted in 1992, included soil, surface water, sediment,
and groundwater sampling at the locations identified in Figure 3-1. The subsections below briefly
discuss the results of the sampling effort
Soil
Fourteen soil samples were collected from a depth interval of zero to two feet. Volatile organic
compounds (VOCs), semivolatile organic compounds (SVOCs), pesticides, potychlorinated
biphenyls (PCBs) and inorganic compounds were detected in the soil samples. The only VOCs
detected in the samples were toluene at 2J micrograms per kilogram (ug/kg) at sample location
16SOS and styrene at 5J fig/kg at sample location 16S06. SVOCs were detected in 10 of the samples
in concentrations ranging from 20 ug/kg to 700 ug/kg. Pesticides were detected in 7 of the samples
in concentrations ranging from 0.40 ug/kg to 7.7 ug/kg. PCBs were detected in 8 of the samples in
concentrations ranging from 13J ug/kg to 880 ug/kg. Several inorganic compounds were detected
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in the soil samples collected from the Round One RI. When comparing the detected organic and
inorganic concentrations to the USEPA Region III Risk Based Concentrations (RBCs), used for
comparative purposes, none of the detected compounds exceeded the RBCs established for industrial
soil, except for arsenic. The RBC for carcinogenic arsenic (industrial soil) is 1.3 milligrams per
kilogram (mg/kg); the RBC for noncarcinogenic arsenic (industrial soil) is 610 mg/kg. At sample
locations 16S12 and 16S14 the detected concentrations of arsenic were 1.7 mg/kg.
Surface Water
Organic compounds were detected in only one surface water sample (16SW03-001). The detected
organics in this single sample included: 1,1-dichloroethene (2J micrograrris per liter [ug/L]),
1,1-dichloroethane (5J ug/L), 1,1,1-trichloroethane (8J ng/L), phenol (27 ug/L), and 4-methylphenol
(850 ng/L). Several inorganic compounds were detected in the surface water samples. At sample
locations 16SW03, 16SW04, and 16SW05, the detected concentrations of arsenic, cadmium,
chromium, copper, lead, mercury, nickel, and/or zinc exceeded the Virginia Water Quality Standards
(VWQSs) and/or the federal standards under the Clean Water Act (CWA).
Sediment
Eight sediment samples were collected (four sampling locations with two samples collected from
each location) from depth intervals of zero to six inches and six to twelve inches. SVOCs, PCBs, and
inorganics were detected in the sediment samples. The SVOCs ranged in concentrations of
21J fig/kg to 1,000 ug/kg. Most of the detected SVOCs were polynuclear aromatic hydrocarbons
(PAHs). PCBs were detected in the two samples collected from sample location 16SD04. The
detected PCB concentrations were 25J fig/kg and 59J Mg/kg. Several inorganic compounds were
detected in the sediment samples. Based on a comparison of the inorganic data to sediment
screening criteria, none of the inorganics exceeded the medium effects range criteria. The detected
concentration of zinc (149 mg/kg) in one sample (16SDO1-001) exceeded the low effects range
criteria of 120 mg/kg.
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Groundwater
Five groundwater samples were collected from existing wells at Site 16. VOCs, SVOCs, explosives,
and inorganics were detected in the samples. The detected VOCs included 1,1,1-trichloroethane,
1,1-dichoroethene, 1,1-dichloroethane, and chlorobenzene. The detected SVOCs included phenol
and 1,1-dicholorobenzene. The detected concentrations of these organic compounds were below the
enforceable federal Maximum Contaminant Levels (MCLs). The explosive, RDX, was detected at
sample location 16GW01 at a concentration of 1.3 ug/L. Several inorganic compounds were
detected in the groundwater samples. Total inorganic concentrations for aluminum, antimony,
beryllium, cadmium, chromium, iron, lead, manganese, mercury, nickel, and zinc exceeded either
the enforceable federal MCLs or the Virginia Primary Drinking Water Standards (PMCLs) in
samples from at least one of the monitoring wells. The dissolved iron concentration detected in well
16GW05 (878J ug/L) exceeded the non-enforceable federal Secondary MCL (or SMCL) of
300 ug/L. The dissolved manganese concentration detected in well 16GW04 (87.2 ug/L) exceeded
the non-enforceable federal SMCL and the PMCL of 50 ug/L.
After the Round One RI, it was determined that additional groundwater information was needed
upgradient and downgradient of Site 16. Additional surface water, sediment, benthic
macroinvertebrate, and fish population information also was needed to evaluate potential risk to the
environment. Also, because SSA 16 is essentially coincident with Site 16 and was expected to have
similar types of contaminants, additional background groundwater information and data was needed
to evaluate the SSA.
Habitat Evaluation
A habitat evaluation was conducted at Site 16 in the late spring of 1994. During this evaluation,
background information on aquatic and terrestrial environments was collected to assist in developing
an ecological risk assessment.
Removal Action
A Removal Action was conducted at Site 16 in 1994. The scope of this action involved the removal
of dry cell carbon/zinc batteries, silica gel desiccant, surface debris, steel cables, underwater mine
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casings, and scrap ordnance located throughout the site. Approximately 420 tons of batteries, 60
tons of debris, 125 tons of silica gel, and miscellaneous ordnance was removed from the site.
Confirmation sampling was conducted to more accurately determine the extent of the removal. In
addition, the EPA's oversight contractor conducted a sampling survey to identify any secondary
sources of the PCBs detected in the sediments and soils during previous investigations. This PCB
sampling survey demonstrated that a potential source area of contamination, not addressed by the
Removal Action, may remain at Site 16 in the vicinity or upgradient of the drainage ditch. These
potential source areas were later addressed and evaluated during the Round Two RI.
The removal of surface debris extended into the subsurface soil in a small area where refuse material
was present at depth. Figure 3-2 identifies the approximate area/extent of the excavation area and
the areas where surficial debris was removed. As previously mentioned, the waste characterization
study indicated that the waste at Site 16 was primarily surficial debris. Following the removal of
the debris/soil, 19 confirmation surface soil samples were collected from the zero to six inch interval
at the locations identified on Figure 3-2. VOCs, SVOCs, pesticides, PCBs, and inorganics were
detected in many of the samples. The VOCs detected in the surface soil samples included methylene
chloride and acetone. The detected concentrations of the VOCs ranged from 4J ug/kg to 120 ug/kg;
they were below the USEPA Region HI RBCs for both residential and industrial soil. The SVOCs
detected in the soil samples included several PAHs and some phthalates. The detected levels of the
SVOCs were below the USEPA RBCs for industrial soil. The detected level of benzo(a)pyrene at
sample location 16SS10 (100J ug/kg) exceeded the USEPA RBC for residential soil (88 ug/kg). The
detected concentrations of the pesticides were below the USEPA RBCs for both industrial and
residential soil. PCBs (Aroclor 1254 and Aroclor 1260) were detected in several of the soil samples.
The industrial and residential soil USEPA RBCs for Aroclor 1254 are 41,000 ug/kg and
1,600 ug/kg, respectively. The industrial and residential soil USEPA RBCs for the general category
of PCBs are 740 ug/kg and 83 jig/kg, respectively. The detected levels of Aroclor 1254 were below
the RBCs (both industrial and residential) except in one sample collected at 16SS10; the
concentration was 2,100J ug/kg. The detected levels of Aroclor 1260 exceeded the PCB RBC
(industrial and/or residential) in 5 of the samples. These Aroclor 1260 concentrations ranged from
87J ug/kg to 1,4001 fig/kg. The detected levels of inorganics were below the USEPA RBCs (both
industrial and residential).
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Round Two RI
The Round Two RI, conducted in late 1994, included surface soil, subsurface soil, groundwater,
surface water, and sediment sampling to supplement the sampling conducted during the Round One
RI and the Removal Action Confirmation Sampling. Sampling locations associated with the
Round Two RI are identified on Figure 3-3. Thirteen surface soil samples were collected at the Site
at a depth of zero to six inches. Subsurface soil samples were collected from three different depths
at each of seven locations. One round of groundwater samples was collected from eleven locations.-
Surface water samples were collected from three locations, and sediment samples were collected
from four locations at two different depth intervals (zero to four inches and four to eight inches).
Fish and benthic macroinvertebrate samples were also collected during this investigation.
Additional details regarding the results of the Round Two RI are presented in the Site Characteristics
(Section 6.0) section of this ROD. Graphical presentations of detected constituents are provided in
Figures 3-4 through 3-11.
3-6
-------
SECTION 3.0
FIGURES
-------
\
DRAINAGE,
STRUCTURE
WTTH BUILDING
NUMBER
RALROAD
FENCE
APPROXIMATE EXTENT
OF SSA 16
GROUND SURFACE
ELEVATION CONTOUR
(FVCT ABOVE
MEAN SEA |£VEU
RGURE3-1
ROUND ONE Rl
SAMFUNG LOCATIONS
NAVAL »e«»B8r*iBNronaci*N KOTOW WON*
-------
BATTCRY/SOII
EXCAVATION
AREA 165519-
DRAINAGE
COCC OF PAVEMENT
NUMRFIR
RARROW)
FFNCF.
E SOII SAMPIE lOTAHON
DCBR5 RCUCVAL W5CA.
RGURE 3-2
REMOVAL ACTION
SAMPUNG LOCATIONS
-------
I Inch « 3OO ft
QRAMAGT.
nri siRucTiiPr.
WIFH Rininus
NUMRtR
COCC OT PAVCUEMT
CBCTIMD SURfUCt
niVAiiON CONIOUP
(ire AIKM.
UKAN SF* irvci.)
. BORINC LOCATION
son SAUPIZ LOCATION
RC3URE3-3
ROUND TWO Rl
SAMPUNO LOCATIONS
SITE 16/SSA 16
IUV«L «E«RM3 STATON TORCTCWN
-------
~
16S23-
S»mlvolatll«l
Phinanttircn*
Ar>lhroe«n*
riuaranlhan*
Pyr«r»*
0«nio(o)oti1hroc«n«
CKryt«n*
B»ni o(b )f lu«ra nl h • n«
Q«nio(li)fluaranrh*n«
Binio(o)pyr«n«
M«no((.2.3-ed)pyr«nB
B»nt o(o.h. DpcrylBn*
39O
120 J
1500
1300
700
1100
iroo
460
650
490
290 J
P«*llcld«i/PCB>
4.4-OOE
4.4-TOO
4,4-001
tndrin K«lon«
A»oc1or-1354
91
5.9
3/
5.6
61 J
•^T^1
^
^
163! 7
Piitlcldos/PCB>
4.4-nnt
Aroctor- 1 J60
4.3
58
16S1B
5*mlvolaltU*
ewl^kill^ranlh^! '" J
P«jllcld.j/fCB<
4.4-DOE
Aroclar-1260
6.4
95 J
165IS
PcittcldM/l'Ctti
4.4-DOE
4.4-DDI
10 J
15
14O J
16S25» ""
P.iMcId
4.4-DOE
4.4-ODF
*/PCB«
130
1EO J
I inch • 300 IL
APPBOXIUATC DOW?
CTOUND SURFACt
ttfVAIlON CONIOUB
(IM1 AB(M.
MEAN SPA LEVO-)
SOIL SAMPLE: LOCATION
CONCfHIRATlQNS EXPRESSED (H u
MOTT::
- SURTACC SOfl. SAUPi;HG LOCAHONS SHOWN WTTHOU1
CONCCNtRAttOHS INOtCAItS MOH-OCTTCIAflU
levttLS SEE 'AHIF.S IN Itm
• snr-SPECIFIC FWCKCROIWO SAMPLE
RGURE3-4
POSTTTVE DETECTIONS OF ORGANIC
COMPOUNDS IN SURFACE SOIL
STTE 16 AND SSA 16
mvu-KEAPcteaTATON renown TOHCTDDHVUCM*
-------
130 300
I loch " 300 It
ORAlNMfc
CDCC OT PAVCUENf
,..,<. APPROXIMATE £Xn;WT
RMROAO ^42 OT SSA 18
rfnri i» CROUNO SUfrACC
FlEVAItON CONtQUR
(MM AOCM;
UEAN SW LFVTL)
c SOIL SAJJPIE LOCATION
BlAStO IOW
. COWCNIRATIOHS
FIGURE 3-5
POSmVE DETECTIONS OF SEUECT
INORGANIC ANALYTES
IN SURFACE SOL
SnE 16 AND SSA 16
IUVM. «EM>ON3 STA1EN rCRODUN
-------
30.3
40.2
I6SB07-OI
Anonlc
Barium
Beryllium
Chromium
Coball
Copp*r
Lead
UanganMO
Mfcke*
Vanadium
2lnc
Anonlc
Barium
Beryllium
Chromium
Cobalt
Copper
Load
Uanganeeo
Nkket
Selenium
Vanadium
Zinc
I6SB07-09
Aluminum
Anentc
Borium
Beryllium
Chromium
Coball
Copper
Lead
Uanganno
Weir el
Selenium
Vanadlunt
Zinc
C-J «.)
5040"
7.3
71.9
0.4
6
15
7
11
5
8
19
(7-9 II.)
10
2
0
1
f
0
2
2
(l'-l
10100
2.8
18.8
I
77. Z
2.5
15.7
9.1
13-9
7.4
0.56
34.5
25.9
j
L
J
R
I
>
J
L
J
J
J
I
J
K
L
i
/
/
--»—
^X
_,
•^"
16SB09-0
Anwtfe
Barium
Chromium
Coball
Copper
load
WongofWM
Vanndlum
Zlrte
16SBO9-OI
Aluminum
Ancnlc
Barium
B-ryKhim
Chrofnlum
Coball
Copper
Lead
Honooneie
Hlcfcol
Solottliim
Vanadium
Zlno
(1-3 «.)
5230
3.3
16.3 J
10
t.8 J
7.2
9.7
14
15.*
12.t J
[3-5 It.)
26200
10.4
49 J
1.2 J
58.5
12 J
«.5
19.4
61.9
18.5
0.44 L
58.3
42.7 L
16SRO8-O
Aluminum
Anonlc
Chromium
Coboll
LMd
Manganese
Van odium
One
1 6S808-O6
A««itc
Barium
•orytllum
Chromium
Cobnll
Copper
Load
UonQoncM
Nkrlcel
Vonadtutn
2>c
Anexlc
Barium
Chromium
Coboll
Topper
UongonoM
Vanadium
One
(1-3 II.)
Jb70 j
14.5 J
5.8
I.B J
3.5 t
23.1 J
B.7 J
4.5
(M-li II.)
28400
2.3 L
34.1 J
0.34 J
33.1
3.6 J
1.6 J
tt.8 L
79 J
6.6 K
41.9
8.7
7950 J
1.8 Jt
15.4 J
14.5
1.5 J
f.6 J
4.4 L
11.8 J
13.5
12.8
Chromh
y Coball
/ Copper
^ toad
I Uongan
•ft Mch«l
't- Vanodlu
/Jnr»c
r^ tr*
\
V
\
\ ;
\ i
\
\
V
\
V
\
'"
^L '
16SB07-0
Aluminum
Ancnlc
BaHum
R«r)HIIum
Chromium
Coboll
Copper
(•ad
UanaariM*
Vanadium
Zinc
16SR02-05
Aluminum
An«nlc
Barium
(•r^tRum
Chromium
Coball
Copper
Load
Mangan«M
Nickel
S.lenkrtn
Vanadium
ZlFK
AEim^I^i '"
Anenlc
Barium
Beryinum
Chromium
Coball
Copper
toad
Uonganeme
Mch«l
Vanadium
Zinc
(t-3 H.l
5fi?n
I.I
33.6
0.78
5.9
3.3
1.7
5.5
81.3
9.6
9.9
[9-11 II.)
14000
25.7
14.3
0
79
1
5
to
7
4
0.
44
a
[25-27
15000
4
50
I
39
•
A.
4
37
74
78
52
L
j
j
j
N
J
J
-
J
J
1
400
I Inch = 300 ft
— - nwuNAcr
L?b snufcium;
WITH BunoiNc '
NIMVR
— H- fwn.ROAn
. — •_ frNCE
tocc or PAVCUEKI
GROUND SURFACE
CtfVAIPON COWIOUB
(I Ml ABlM,
MfAN SEA IJVn>
SAUPU LOCAIKW
F
CSTIUATtO
B1ASCD IICM
OlASCD LOW
CONCENTRAnONS fKPSf 5SCO IN mq/Vq.
STTt-SPICrtC BACKCROUMO SAUPIE
RQURE3-6
POSTTIVE DETECTIONS OF SELECT
WOHOANIC ANALYTES
IN SUBSURFACE SOL
SfTE 16 AND SSA 16
WVAL HEATONB STAHOK IWtC1D«N
-------
I inch « 300 ft
DRAINAGE
WIT* BU1L.I1
RAIL ROAD
• COCC Of P4VCMCMT'
CROUNOSURFACC
HCVAIION CONinut
irCCT «KJWE UCAN
w/»0l CRCHtNOWAim MONTTOnfMC WEIL/
0 SOU BORiMC LOCAnON (BAKER. 1994)
» MONITORING WEIL
NS TALI ft] (DAM^S * MOORE, 19B8)
COMPOUND CONCENTRATIONS EXWESSCO N u
* sm -spictnc HACKGBOUND SAMPIC
MOT?:
RQUnE3-7
POSmVE DETECTIONS OF
ORGANIC COMPOUNDS IN
OflOUNDWATER
SfTE 16 AND SSA 16
H»V«_ VEAPON9 STAim TOHCTOHN
-------
Alumlnu
Artllmon
Amnlc
Barium
Cobalt
Copp*r
MongorM
S*1*nlurr
Zinc
IGCW05-01
Total
r N
21. L
25. J
3. J
y j
*• 2?
3. J
9.
9i»ol*«d
NO
19.3 J
ND
22.1 )
HO
l.fl J
14.9 J
HO J
11.0
Aluminum
Barium
Barrlltum
Chromium
Coppw
Lead
Uangon***
S«UnTum
Vanadium
Ztnc
16CW07-OI
Total
990
13.0 .
0.2S
2
4.6
2.4
54.0
3.1
3.9
(6.4
Dls»otv«d
NO
70 J
NO
NO
J
N
51.
NO
2. J
J
Aluminum
Ar*«n>c
Barium
B*r>lllum
Chromium
Cobalt
Copp«r
L*od
Mangon«9*
Hklt«l
S*l>n1um
Vanocfum
Ztnc
6CW04-OI
total
10800
0.1 L
67.6 J
0.93 J
27.
9 J
0 J
7.
12
19 J
4. J
35. J
SO
DtMotvcd
HO
HO
27.8
NO
NO
NO
3
ND
69.4
ND
ND
2.4
5.3
16GW09-O1
total DHic4v«d
Aluminum
Ar-Mnlc
Barium
Chromium
Copp*r
WangantM
S*l«nlum
VanodKjm
Zinc
1030
S J
25.7 J
2.8 J
4.4 J
14«
NO
4.5 J
24.9 J
HO
S.9 K
1B.I J
HO
3.4 J
It4
2.9 J
2.2 J
5 J
1 Inch * 300 IL
*- RMROAD
1- FENCC
cocc or PAVCUCKT
GROUND SURFACE
ELEVATION CONTOUR
(fitI ABOVE
UFAM $EA LEVTL.)
MYDROP1JNCM SAUP1L IOCAUON
ttCVOJ
if) CROUMOWATCR UOWTOWMC WELL
PRCVKHJSl/c W5TAI1ED (DAMES ft UOORC. 1986)
H* NOT «HM.v7n>
NO NCI OTTICTTO
J ESUUAIFD
K BIASt.n HIGH
L R1ASCD LOW
ANAI.VTE CONCEKTRATKJMS EXPRCSSCO W »jqA
FIGURE 3-8
POSITIVE DETECTIONS OF SELECT
INORGANIC ANALYTES
IN GROUNDWATER
SITE 16 AND SSA 16
NAVAL KEIPON9 STATION TCHODUM
-------
I6SWO9
Aluminum
Artinlc
Barium
l*od
Wongonci*
S«Unlum
H«e
Tola!
99 J
ND
35.3 J
5.9
70S
1.2 J
5.6 J
Olitohwd
9!.l J
1 J
37.4 J
NO
199
1.2 J
9.1 J
16SW/SD09
SITE
16SW/SD07
16
Aluminum
An.nlc
Barium
Cwp.r
Uangan«»
S«l«nlum
Zinc
16SW06-
Total
41. J
2. JL
39. J
N)
37 J
1. L
3.2 J
ili»ol**d
129 J
2 L
39.2 J
yt j
302 J
NO
11.9 J
1 inch « 300 ft
---- (1RAJNACC
RAIPOAD
irwcf:
C DCC Or PAVCUtNt
GROUND SURfACC
HJVAIHW CON I OUR
(MM ABIM;
T SAMPI.F. IOCAPON
R3URE3-9
POSfTTVE DETECTIONS OF SELECT
INORQAN1C ANALYTES
IN SURFACE WATER
SfTE 16 AND SSA t6
KIVAL WEAPONS STAICN TOROOKN
YOKIDWlVRHt
-------
190 300
I inch - 300 fi
SSVWU^^SB1™01
MUMRCn ^^* DISPOSAL
CLEVATXM* CO
(rtCT *BOVE UCAN
M> IFVTL)
»in*/Sft)iuFNt SAUPI.E LOCAOOM
J ESTIUMEO
COMPOUND rONCEMTTWITONS DEPRESSED IN uq/kg
-SCWMtHl SAMPLING LOCATIONS SHOWN
WTTVOUT CONCENTRATIONS INDICATES
NOW-DETECTABLE LCVUS.
SEC TABLES IN TEKT.
' SHE-SfECFIC BACKCPOUNO SAMPLE
HGURE3-K)
POSTTIVE DETECTIONS OF
ORQAMC COMPOUNDS IN
SEDIMENT (0-4') AND
SUBSURFACE SEDIMENT (4-81)
STTE 16 AND SSA 16
VOROOON VR»U
-------
t 65009-01
Aluminum
krvmn\c
ftaitvm
Bviylllum
Chiottilum
Cobalt
Copp«
L*0d
Mangonn*
Nlelrcl
S*l«nlum
Vanadium
Tine
_
3MO
3.1 I
13.5 J
MO
8.S
2.1 J
3.3 J
5.1
6(1.2 I
HO
NO
12.5 3
76.6
>
1 6SD09 -0?
Aluminum 1
Art*nlc
BoHum
B*ryillum
Chromium
Coboll
C«PP«r
l.od
Mangan*i»
Hlckal
Svbnlum
Vanadium
Zinc
7M mrlr=
4300
4,6
2B.3
0.8*
336
3.4
8.2
11.3
us
12.3
0.68
35.3
37
5=-^
P-480
Jci^./B."*"*114113'
'•-^•W-^V-—.
16SW/SD09
I6SD07-OI
Aluminum 2250
Ananlc
BnHum 8
GviYOIurn 0.
Cadmium
Chfotnlum 3
Cotoall
Copp»r 1
I*a4 3
Uanoon.t.
NIcbBl Z
S*l«ilum 0
Sllvw
Vanodlufn 5
?lnc 1
N,
n\
If
I6SOOT-OI
Aluminum 16700
Afl.nlc 4.1
aaHum 63.9 J
B*ryilum 0.7S J
Cottmlum 2.6
Chromtum 31. 7
CoboH 8.8 J
Capp«r (11 J
LMK| 73.3 J
UangorMi* 61 J
Nleh«l 1 7.3
S«l«nlum 0.3 J
SIMr 2.3 J
Vanadium 30.7
Zinc 66.7
16SW/SD08
5K5IT.E '
I6SW/SD07
16SW/SD
16SD06-OI*
Aluminum
Amnlc
Bortum
Rarfdlum
Chromium
Cobalt
Copper
l*nd
Watiganci*
Mtclc*!
SHv«r
Vanadium
Zinc
49OO
7,2
24.4 J
NO
10.9
ND
94.8
17.2 J
101 J
NO
3.4 J
71 J
49.B
!6S006-07B
Aluminum
AfMflfc
Bortum
Biryffliim
Chromium
Cabal!
Copper
l«od
Uangantst
Nttkri
Sll*«r
Vanadium
Zinc
tsooo
10.3
30.3
0.3
74.
3.
3.
34.
62.
1
N
32.3
76.7
I inch - 300 IL
---- ORAINACC
t~-t smucn^e
wmi Buiin
tOCC Of PAVCUENT
APPROXIMATE DfTt
QT SSA 16
GROUND SUBCACC
HfV*'ION CONIOU
(DM A8OV1
MEAN SEA l^Vn)
T SAMPlE LOCAOON
L BIASED LOW
NO NO' DfllCTTO
ANA1.TT1 CONCENTRATIONS FVPRESSF.O IN mg/ig.
RGURE 3-n
POSITIVE DETECTIONS OF SB.ECT
INORGANIC ANALYTES
IN SEDIMENT (0-41) AND
SUBSURFACE SEDIMENT (4-81)
SITE 16 AND SSA 16
-------
4.0 Highlights of Community Participation
The Final RI Report and the Final Proposed Remedial Action Plan (PRAP) for Site 16/SSA 16 at
WPNSTA Yorktown were released to the public on July 25, 1995. These documents were made
available to the public at the information repositories maintained at:
• York County Public Library
• Gloucester Public Library
• Newport News City Public Library (Grissom Branch)
• WPNSTA Yorktown, Environmental Directorate, Building 31 -B
A notice, of availability, including a brief analysis of the PRAP, was published in The Daily Press
on July 23,1995. A public comment period was held from July 25,1995 to September 8,1995. In
addition, an Open House and Public Meeting was held at the York County Social
Services/Recreation Center Meeting Room, Goodneck Road, Yorktown, Virginia on August 23,
1995. The purpose for this meeting was for the DoN, USEPA, and the Commonwealth of Virginia
representatives to answer questions and accept public comments on the PRAP for Site 16/SSA 16.
Responses to the written and verbal comments received during the comment period are included in
the Responsiveness Summary section of this ROD. This decision document presents the selected
remedial action for Site 16/SSA 16 chosen in accordance with CERCLA and, to the extent
practicable, the NCP. The selected remedy for this Site is based on the administrative record file.
4-1
-------
5.0 Scope and Role of the Response Action
The selected remedial action identified in this ROD is the final recommended action for
Site 16/SSA 16. Previous actions implemented at the site have mitigated the potential for human
health risks and ecological effects associated with the area under the current and predicted future
land use for WPNSTA Yorktown. Therefore, no further remedial actions with the exception of
institutional controls will be conducted at Site 16/SSA 16. As was previously mentioned, prior to
the initiation of the Round Two RI for Site 16/SSA 16, a Removal Action was conducted. The
Removal Action consisted of the removal of visible debris including batteries, silica gel desiccant,
construction debris, mine casings, and scrap ordnance. A series of confirmation surface soil samples
were collected as part of the Removal Action and were evaluated in the baseline risk assessments
presented in the Round Two RI. The No Further Remedial Action Decision with Institutional
Controls was based on the results from both the Removal Action confirmation sampling and the
Round Two RI sampling (the justification for this decision will be detailed in Section 8.0 of this
document). The institutional controls (land-use and aquifer-use restrictions) will be utilized to
insure that future residential use of Site 16/SSA 16 is controlled by the DoN.
Site 16/SSA 16 has been designated as OU II. The No Further Remedial Action Decision with
Institutional Controls is the final action for OU D. Other operable units for other WPNSTA
Yorktown sites will be defined by separate investigations.
5-1
-------
6.0 Site Characteristics
This section of the ROD presents an overview of the nature and extent of contamination at
Site 16/SSA 16 with respect to known or suspected sources of contamination, types of
contamination, and affected media. This discussion is based on the results of the Removal Action
and the Round Two RI.
• Potential Contaminant Source Areas
Two major potential contaminant source areas at Site 16/SSA 16 have been identified: the Site 16
disposal areas, and the SSA 16 metal disposal area. As previously stated, Site 16 operated as a
disposal area for wastes such as dry carbon-zinc batteries, banding materials, pressure transmitting
fluid, silica gel desiccant, mine casings, scrap ordnance, and construction debris. The 1994 Removal
Action removed the surficial debris and waste, thereby, removing the potential sources of
contamination from this site.
SSA 16 was used for scrap metal storage. Scrap metal had been identified at the SSA in dumpsters
and also scattered over the ground surface near the dumpsters. As with Site 16, the 1994 Removal
Action removed the surficial debris, thereby, removing the potential sources of contamination from
this area.
• Identified Contaminants of Concern
Surface Soil
Surface soil was sampled at thirteen locations from a depth interval of zero to six inches. PCBs,
SVOCs, pesticides, and inorganics were detected in these samples. PCBs were detected in 6 of the
soil samples at concentrations ranging from 40 ug/kg to 140J ug/kg. The industrial soil USEPA
RBC for PCBs was not exceeded by these samples. The residential soil PCB RBC of 83 ug/kg was
exceeded in one sample at 16S18 at a concentration of 85 J ug/kg of Aroclor 1260. Drums, cables,
or other items previously stored on site were most likely the source of these PCBs. Pesticides and
SVOCs also were detected hi surface soil, but appeared to be due to anthropogenic sources. One
sample (16S23) had SVOCs detected at levels exceeding the USEPA RBC for residential soil, not
6-1
-------
for industrial soil. The detected benzo(b)fluoranthene and benzo(a)pyrene concentrations in this
sample were 1,700 ng/kg and 650 ng/kg, respectively. The residential soil RBCs for these two
compounds are 880 ug/kg for benzo(b)fluoranthene and 88 ug/kg for benzo(a)pyrene. The detected
levels of pesticides in the soil samples were below the USEPA RBCs for both industrial and
residential soil. The inorganic compounds detected in the soil samples were at levels below the
USEPA RBCs for industrial soil.
Subsurface Soil
Subsurface soil was sampled from two to three different depths at six locations. No organic
contaminants of concern were detected in the subsurface soil samples, indicating that contaminants
detected in the surface soil have not migrated vertically. Several inorganics were detected in
subsurface soil. The detected inorganic concentrations were below USEPA RBCs for industrial soil
with the exception of arsenic and beryllium. The industrial soil RBC for arsenic (carcinogenic) is
3.3 mg/kg. Seven subsurface soil samples contained arsenic at levels exceeding this value: 16SB01-
05,16SB01-11,16SB02-05,16SB02-13,16SB06-ll,and 16SB09-02. The samples were located
at depths between 3 and 27 feet below ground surface. The industrial soil RBC for arsenic
(noncarcinogenic) is 610 mg/kg. No subsurface soil sample has arsenic levels exceeding this value.
The industrial soil RBC for beryllium is 1.3 mg/kg. Two subsurface soil samples had beryllium
levels exceeding this value. Sample 16SB06-11 (21 to 23 feet) contained beryllium at 2 mg/kg and
sample 16SB02-13 (25 to 27 feet) contained beryllium at 1.8 mg/kg.
Groundwater
Groundwater samples were collected from four newly installed monitoring wells, and five existing
monitoring wells. VOCs, SVOCs, pesticides, and inorganics were detected in the groundwater
samples. The concentrations of the detected VOCs and SVOCs were below the enforceable federal
MCLs and Virginia PMCLs. Pesticides also were detected in groundwater, but these compounds
were likely due to soil particles being entrained in the groundwater during sampling. Several
inorganic compounds (total and dissolved) were detected in the groundwater samples collected
throughout the site. Antimony (dissolved) and manganese (total and dissolved) were the only two
inorganics which had detected levels exceeding the enforceable federal MCL or non-enforceable
federal SMCL. Antimony was not detected in the total fraction but was detected in the dissolved
6-2
-------
fraction at concentrations of 13.1 ug/L (16GW06) and 19.3J ug/L (16GW05). The enforceable
federal MCL for antimony is 6.0 ug/L. Manganese was detected at concentrations ranging from
9.9J ug/L to 146 ug/L in the total fraction and from 1.9J ug/L to 114 ug/L in the dissolved fraction.
The non-enforceable federal SMCL for manganese is 50 ug/L.
Surface Water
Surface water was sampled at three locations at Site 16/SSA 16. Organic contaminants were not
detected in surface water samples. Inorganics were detected in surface water, but their detected
concentrations were generally below the CWA criteria and the VWQSs.
Sediment
A total of eight sediment samples were collected (four sampling locations with two samples
collected from each location) from depth intervals of zero to four inches and four to eight inches.
PCBs were detected in both the surface and subsurface sediment samples from the sampling location
immediately downgradient from the site. The presence of PCBs at this location was likely the result
of erosion, transport, and redeposition of PCB-contaminated surface soil particles from the former
disposal area. Pesticides also were detected in sediment samples, but were likely due to an
anthropogenic source. Carbon disulfide was detected in two sediment samples and was likely the
result of bacteriological decomposition of vegetation and other organic matter in the stream.
Inorganics detected in sediment were generally at levels below the effects range-low sediment
screening values. One sample (16SD06-02) contained copper and silver that exceeded the effects
range-low sediment screening values. The detected concentrations of copper and silver in this
sample were 94.8 mg/kg and 3.4J mg/kg, respectively.
• Affected Media
Based on the results of Round Two RI, the affected media at Site 16/SSA 16 appeared to be surface
soil (PCBs), groundwater (VOCs), and sediment (PCBs).
6-3
-------
7.0 Summary of Site Risks
As part of the Round Two RI, baseline human health and ecological risk assessments were
conducted to evaluate the potential risks associated with exposure to contaminated environmental
media at Site 16/SSA 16. The baseline risk assessments considered the most likely routes of
potential exposure for both current and future risk scenarios. A summary of the key findings from
both of these studies is presented below.
• Human Health Risk Assessment
The human health risk assessment was conducted for four environmental media including soil
(surface and subsurface), groundwater, surface water, and sediment. Contaminants of potential
concern (COPCs) were selected for each of these media as shown on Table 7-1. Note that the
COPCs were based on the Removal Action and the Round Two RI.
The potential receptors evaluated in the human health risk assessment included current adult
workers, future resident adults, future resident children, and future construction workers. The future
resident scenario was evaluated as a conservative measure. Furthermore, the future residential
development of Site 16/SSA 16 is highly unlikely given its location within the restricted area of the
Station and the newly-constructed security fence that encloses the restricted area.
As part of the human health risk assessment, incremental cancer risk (ICR) values and hazard index
(HI) values were calculated for each of the exposure routes and potentially exposed populations.
An ICR refers to the potential cancer risk that is above the background cancer risk in unexposed
individuals. For example, an ICR of 1 x 10"04 indicates that exposed individuals have an increased
probability of one in ten thousand of developing cancer subsequent to exposure over the course of
their lifetimes. USEPA considers the target ICR range of 1 x lO"04 to 1 x 10* to be generally
acceptable. The HI value is an estimated measure of noncarcinogenic effects; it is a ratio of the level
of exposure to an acceptable level for all COPCs. A HI less than 1.0 indicates that adverse
noncarcinogenic health effects are unlikely to occur subsequent to exposure. A HI greater than 1.0
indicates there is a potential for adverse noncarcinogenic health effects to occur at that exposure
level.
7-1
-------
Table 7-2 summarizes the maximum ICR and HI values that were calculated in the human health
risk assessment for Site 16/SSA 16. As shown on the table, all of the media/potential receptors
evaluated had ICRs within the USEPA's acceptable risk range. The HI values were below 1.0 except
for the future residential scenarios. The His were calculated as 1.8 and 5.2 for the future adult
resident and future child resident, respectively. The HI values were primarily driven by the presence
of antimony (at 57% of the total HI). A definite source of antimony has not been detected at
Site 16/SSA 16.
Results of the human health risk assessment indicate that potential carcinogenic as well as systemic
(or noncarcinogenic) adverse health effects could occur for future residents exposed to affected
environmental media at Site 16/SSA 16. The total site risk and HI values for future residents were
1.6X10"4 and 7.0, respectively. These values were derived by adding the carcinogenic risks and
hazard indices (His) for every potential exposure route and affected medium for both children and
adults receptors.
Total Site Risk
Total site risks for future potential residential adults and children are 9.4x1 O*5 and 6.5x10 -J,
respectively. These risk values fall within USEPAs target risk range of 1x10* to 1 xl 0"*, which is
generally considered to be acceptable for most sites. The presence of dissolved arsenic in
groundwater and total arsenic in surface soils accounts for approximately 60 percent of the risk to
both children and adults.
Arsenic was detected in 24 of 26 Site 16/SSA 16 surface soil samples at concentrations ranging from
2.1 J to 20 mg/kg. The upper 95 % confidence value of the arithmetic mean arsenic concentration,
derived for use in the baseline risk assessment, was 6.08 mg/kg. Arsenic was also detected in 44 of
44 background surface soil samples obtained from throughout the Station. Background arsenic
concentrations ranged from 0.46L mg/kg to 63.9 mg/kg, with an upper 95 % confidence arithmetic
mean value of 5.7 mg/kg. In general, background concentrations of arsenic are similar to site related
concentrations of arsenic. Although the Site 16/SSA 16 upper 95 % confidence value is slightly
higher than the background upper 95 % confidence value, approximately 90 percent of the future
potential risks to future resident children and adults can be attributed to naturally occurring
concentrations of arsenic in surface soils.
7-2
-------
C.I--H rctu J nwnu P.04/03
Dissolved arsenic was detected in 1 of 10 Site 16/SSA 16 shallow groundwater samples at a
concentration of 5.9 ug/L, well below the enforceable MCL value (and Virginia's MCL) of SO ug/L.
Furthermore, dissolved arsenic was detected in 2 of 18 background wells with a maximum detected
concentration of S.5L ug/L. Potential human health risks associated with the presence of dissolved
arsenic in groundwater at Site 16/SSA 16 can be attributed to the sporadic natural occurrence of
arsenic in shallow groundwater and not past site activities.
Total Site His
Total site HI values for future potential resident adults and children exceed 1,0, suggesting that
adverse systemic or noncarcinogenic human health may occur subsequent to exposure. HI values
of 1.8 and 5.2 for adults and children, respectively, are driven by the presence of dissolved
antimony, arsenic and manganese in Site 16/SSA 16 groundwater samples.
Adult residents exposed to these dissolved inorganic constituents through the future potable use of
groundwater, produce an HI value of 1.3, whereas children produce an HI value of 3.0. The
presence of dissolved antimony accounts for approximately 60 percent of the HI values. Antimony
was detected in 2 of 10 site wells (16GW05-01 and 16GW06-01) sampled during the Round Two
RI. The detected concentrations of dissolved antimony were 19.3 jig/L (in a well located on the
western periphery of Site 16, 16GW05-01) and 13.1 ug/L (in an upgradient well, 16GW06-01).
These values exceed the enforceable federal MCL value of 6 ug/L. However, dissolved antimony
was also detected in 5 of 18 background groundwater samples in excess of the enforceable federal
MCL value. Background dissolved antimony concentrations ranged from 16.7J ug/L to 21.1J ug/L.
The presence of antimony in Site 16/SSA 16 groundwater samples can. be attributed to naturally
occurring concentrations in Station shallow groundwater and not Site 16/SSA 16 activities.
An HI value in excess of 1.0 was also derived for future resident children potentially exposed to
Site 16/SSA 16 surface soils. The inorganic constituents antimony (18 %), arsenic (17%), cadmium
(16%), chromium (20 %) and the organic contaminant Aroclor 1254 (14%) accounted for more than
80 % of the elevated HI value. Individual hazard quotient values (HQs) for these constituents do
not equal or exceed 1.0 and range from 0.2 (Aroclor 1254) to 0,3 (chromium). Target organs
affected by these chemicals include the skin (arsenic), the blood (antimony), renal cortex (cadmium),
and the immune system (Aroclor 1254). Chromium, in it's hexavalent (+6) state can also affect the
7-3
-------
skin. Therefore, only HQs for chromium and arsenic should be summed, resulting in an HI value
of 0.57. This HI value falls below 1.0 indicating that systemic effects to the skin will not occur
subsequent to future potential residential exposure to Site 16/SSA 16 surface soils by children.
Summary
Although total site risk and His indicate that potential unacceptable cancer risks and systemic health
effects could occur if Site 16/SSA 16 were used for residential purposes, ICRs and HI values are
driven by constituents that are related to background conditions at the Station. This is particularly
true for shallow groundwater which contains dissolved arsenic and antimony. These constituents
were detected at similar concentrations in background wells located throughout the Station in areas
unaffected by Site 16/SSA 16 activities. Furthermore, shallow groundwater is not likely to be used
as a future potable source because of the relatively low water yields produced by the shallow aquifer.
The shallow aquifer at Site 16/SSA 16 is the Comwallis Cave aquifer.
The shallow aquifer system within York Co. is comprised of the Columbia, Cornwallis Cave and
Yorktown-Eastover aquifers and their associated confining units. Potable water sources from the
shallow aquifer system are drawn from the Columbia and Yorktown-Eastover aquifers. The
Columbia Aquifer is not present at Site 16/SSA 16. The Cornwallis Cave aquifer is not used as a
potable water source due to its limited yields. (Oral communication between Baker Environmental,
Inc. and Terry Wagner - Environmental Program Manager in the office of Groundwater
Management-VADEQ on July 17, 1995). This is also supported in A.R. Brockman and
D.L. Richardson's Report "Hydrogeology and Water Quality of the Shallow-Groundwater System
in Eastern York County, Virginia" where it is stated that the Cornwallis Cave aquifer is not used as
a public or domestic water supply.
• Ecological Risk Assessment
An ecological risk assessment was conducted at Site 16/SSA 16 to evaluate the potential for past site
operations to have adversely affected the ecological integrity of the terrestrial and aquatic
communities of or adjacent to the sites. The ecological risk assessment evaluated the analytical
results from surface soil, surface water, and sediment samples collected during the Round Two RI
and/or the removal action. In addition, benthic macroinvertebrate and fish species were collected
7-4
-------
and identified during the field investigation. Ecological COPCs were selected for surface soil,
surface water, and sediment as shown on Table 7-3.
The ecological risk assessment was divided, into aquatic and terrestrial portions, based upon the
ecosystems at risk and the data available to evaluate risk. The aquatic ecosystem was evaluated by
the calculation of benthic macroinvertebrate species diversity, richness and a comparison to
ecologically similar background locations. In addition, the aquatic ecosystem was evaluated by
determining the exceedances of contaminant-specific surface water and sediment effect
concentrations and an increase of any gross external fish pathologies.
The terrestrial portion of this assessment included the determination of exceedances of contaminant-
specific soil benchmark values established in the literature and by evaluation of specific effect doses
by the use of terrestrial food chain models. The assessment endpoint for the terrestrial ecological
RA is the reduction of a receptor population or subpopulation that is attributable to contaminants
from the site.
With respect to the aquatic ecosystem, only one inorganic compound detected in the surface water
exceeded screening levels and background concentrations. The sediment at Site 16/SSA 16
contained VOC, pesticides, and inorganics.
The vast majority of constituents detected in sediment samples were present in concentrations below
the ER-L (Effects Range-Low). None exceeded the ER-M (Effects Range-Medium). Sediment
samples collected downstream of the site, in the stream emptying into Felgates Creek, contained no
exceedances of the ER-L. The surface water and sediment quality in Felgates Creek will continue
to be evaluated during subsequent studies at other WPNSTA Operable Units.
Surface soil exceedances of literature toxicity benchmark values indicate the potential for the
ecological COPCs to be adversely impacting the terrestrial flora and fauna at Site 16/SSA 16.
However, most of these studies do not take into account the soil type, which may have a great
influence on the toxicity of the contaminants. For example, soil with high organic carbon content
will tend to absorb many of the organic ecological COPCs, thus making them less bioavailable to
terrestrial receptors. The benchmark values are based on both field and growth chamber studies;
therefore, the reported toxic concentrations are not always equivalent to actual field conditions. In
7-5
-------
addition, the majority of the benchmark values used for comparison purposes had low levels of
confidence assigned to the values based on the number of studies performed (less than ten studies)
and the diversity of species tested.
There is uncertainty in assessing the terrestrial environment using these benchmark values. Various
inorganics in surface soil have a high degree of variability. The high degree of variability of
inorganic concentrations in surface soil in turn magnify the uncertainty associated with using
literature toxicity values to assess potential risk posed to the terrestrial environment.
Terrestrial uptake modeling suggested that a small potential for effects on raccoons (Quotient Index
[QI] = 7.25), quail (QI = 2.96) and white-tailed deer (QI = 1.13) could occur. Because of the
conservative estimates used in the modeling effort, QI values between 1 and 10 do not suggest the
need for further remedial action to protect the health of these potential receptors. However, the
cottontail rabbit model (QI = 30.7) indicates a significant potential for adverse effects to occur to
the rabbit population. However, the ecological COPCs driving the risk to these species through
modeling are also driving a risk to the same species when background concentrations are used in the
models.
The shrew model (QI = 2,250) did exceed the acceptable QI range (less than 100). However, there
are other factors incorporated within the shrew model which contributed to this high QI. There is
a high degree of uncertainty involved with the use of the shrew model. This model assumes that
ninety percent of the shrew's diet is earthworms and the concentration of the ecological COPCs in
the earthworm is considered equivalent to the concentration of the ecological COPCs in the surface
soil. The model does not take into account that the shrew may ingest other soil invertebrates, not
exclusively worms. In addition, the assumption that the soil concentration is equivalent to the worm
concentrations does not consider the bioavailability of the ecological COPCs to the worm. The
model assumes that all ecological COPCs in the soil are bioavailable to the worm. The model is
very conservative, which is demonstrated by the high risk to the shrew presented by background
concentrations. The background shrew value was calculated as QI = 891. Note that the background
shrew model was conducted using background surface soil and surface water data only for the
ecological COPCs for Site 16/SSA 16. In addition, some of the inorganics driving the shrew model
(aluminum and iron) are probably a result of regional conditions and not site-related chemicals.
Therefore, the shrew model most likely overestimates the terrestrial risk posed by Site 16/SSA 16.
7-6
-------
SECTION 7.0
TABLES
-------
TABLE 7-1
SUMMARY OF CONTAMINANTS OF POTENTIAL CONCERN
EVALUATED IN THE HUMAN HEALTH RISK ASSESSMENT™
SITE 16 AND SSA 16
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Contaminant of Potential
Concern
Soil
Surface
VOLATILE ORGANICS
1,1-Dichloroethene
1,1-Dichloroethane
1,1,1 ,-TrichIorethane
Trichloroethene
Tetratchloroethene
Subsurface
SEMTVOLATILE ORGANICS
1 ,4-Dichlorobenzene
Benzo(a)pyrene
•
Pesticides/PCBs
Aldrin
4,4'-DDT
Aroclor-1254
Aroclor-1260
•
•
INORGANICS
Aluminum
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Copper
Lead
Manganese
Mercury
Vanadium
•
•
•
•
•
•
•
•
•
•
•
•
•
•
• •
•
•
•
Groundwater
Total
Dissolved
Surface Water
Sediment
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
(l) The contaminants of potential concern listed were developed for the Round Two RI.
-------
TABLE 7-2
SUMMARY OF MAXIMUM (CR AND HI VALUES CALCULATED
IN THE HUMAN HEALTH RISK ASSESSMENT
SITE 16 AND SSA 16
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Environmental Media
Surface Soil
Subsurface Soil
Groundwater
Surface Water
Sediment
Totals
Potential Receptors
Civilian Worker
ICR<'>
2.0 x lO"05
NA<3>
NA
1.1 x 10-06
1.5xlO-°s
3.6 x 10-05
HI<2>
0.29
NA
NA
0.20
0.11
0.6
Future Adult
Resident^
ICR
2.7 x 10"05
NA
6.4 xlO-05
1.8 xlO"07
2.7 xlO-06
9.4 xlO-05
HI
0.41
NA
1.3
0.03
0.02
1.8
Future Child
Resident^
ICR
2.5 x lO"05
NA
3.7 x 10-05
2.0 x 10-07
3.2 x 10-06
6.5 x 10-03
HI
2.0
NA
3.0
0.09
0.1
5.2
Future Construction
Worker
ICR
NA
1.9 xlO-06
NA
NA
NA
1.9 xlO-06
HI
NA
0.5
NA
NA
NA
0.5
(I) ICR = Incremental Cancer Risk.
<*> ffl = Hazard Index.
m NA = Media was not a concern for this receptor.
(4> Note that for the baseline risk assessment, the HI and ICRr values for the residents are the sum total of the
resident adult and resident child HI and ICR values, respectively.
-------
TABLE 7-3
SUMMARY OF CONTAMINANTS OF POTENTIAL CONCERN
EVALUATED IN THE ECOLOGICAL RISK ASSESSMENT
SITE 16 AND SSA 16
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Contaminant of Potential
Concern
Surface
Water
Sediment
Surface
Soils
VOCs
Carbon Disulfide
Toluene
•
•
PESTICIDES/PCBS
Endrin Aldehyde
Total PCBs
•
•
•
INORGANICS
Aluminum
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Copper
Iron
Lead
Manganese
Mercury
Nickel
Selenium
Silver
Vanadium
Zinc
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
-------
8.0 Description of the No Further Remedial Action Decision with Institutional Controls
• Description
As was previously mentioned, the selected alternative for Site 16/SSA 16 is the No Further Remedial
Action Decision with Institutional Controls. Because the Removal Action conducted in 1994
mitigated potential unacceptable risks to human health and the environment under the current and
predicted future land use for WPNSTA Yorktown, this alternative involves taking no further
remedial actions (including sampling) at the site with the exception of instituting land-use
restrictions and aquifer-use restrictions. The No Further Remedial Action Decision with
Institutional Controls is justifiable because the conditions at Site 16/SSA 16 are currently protective
of human health and the environment. Although risk levels at Site 16/SSA 16 under the future child
resident scenario are within the generally accepted risk range, institutional controls have been
included as a conservative measure. These controls will be utilized to insure that future residential
land use of Site 16/SSA 16 will be controlled by the DoN.
• Rationale
The following section provides detailed rationale of why the No Further Remedial Action with
Institutional Controls Decision is the selected alternative for Site 16/SSA 16. Because the human
health and ecological risk assessments indicated that potential human health and ecological effects
associated with Site 16/SSA 16 are limited, the DoN performed a pre-evaluation to determine if a
Feasibility Study (FS) was necessary for Site 16/SSA 16. One of the first steps of this pre-evaluation
was to evaluate areas of concern for each of the media of concern identified in the RI risk
assessments. Areas of concern were identified by comparing COPC concentrations to Federal and
Commonwealth standards (or if a standard was not established for a specific COPC, a site-specific,
remediation goal option was calculated). The sample locations that exceed the Federal or
Commonwealth standards (or the risk-based value if no standard existed) were evaluated to see if
they could be grouped into an area of concern. A summary of the evaluation conducted to determine
if Site 16/SSA 16 had groundwater or surface soil areas of concern follows:
8-1
-------
Grovndwater Areas of Concern
Groundwater COPC concentrations were compared to the Federal MCLs, which are drinking water
standards designed for the protection of human health, and to the Commonwealth of Virginia
PMCLs. Table 8-1 lists the MCLs and the Virginia PMCLs for the Site 16/SSA 16 groundwater
COPCs. In addition, the remediation goal options calculated for the COPCs without an established
MCL/PMCL, the maximum detected COPC concentrations, and the sample locations that exceed
the criteria are included on the table.' Based on a comparison of the COPC concentrations detected
at Site 16/SSA 16 to the listed standards, there are no groundwater areas of concern that would
require remediation.
As shown on Table 8-1, only three COPCs had detected concentrations exceeding the groundwater
criteria or the remediation goal option: aluminum, antimony, and manganese. As previously
mentioned, the detected concentrations of aluminum, antimony, and manganese were within or near
the range of contaminant.concentrations detected in WPNSTA Yorktown background samples
reported in the Final Background Report for WPNSTA Yorktown. The background concentration
ranges for these three inorganics were 44.9 ug/L to 14,600 ug/L for aluminum; 16.4 ug/L for
antimony; and 4.5 ug/L to 413 ug/L for manganese. As shown on Table 8-1, with the exception of
antimony, the dissolved (filtered) inorganic concentrations were significantly less than the total
concentrations indicating that the inorganics are not a groundwater concern.
It also is important to note that the human health risk assessment concluded that groundwater was
a potential media of concern primarily due to the presence of total arsenic, total manganese, and
dissolved antimony. The detected levels of arsenic did not exceed a Federal MCL or Virginia
Secondary MCL (SMCL). The detected levels of manganese exceeded only the Federal SMCL,
which is not an enforceable regulation. The detected levels of dissolved antimony exceeded the
federal MCL, but not the WPNSTA Yorktown background levels.
Therefore, based on the above-mentioned information, no areas of concern were identified for the
groundwater at Site 16/SSA 16 and no further remedial action other than institutional controls was
deemed necessary.
8-2
-------
Soil Areas of Concern
Based on the conclusions of the ecological risk assessment, the contaminant concentrations detected
in the surface soil samples were evaluated to determine areas of concern that may require
remediation at Site 16/SSA 16. With respect to ecological risks, there are no enforceable numerical
standards or criteria that can be applied to surface soil. Therefore, the surface soil data could not
be compared to any set of standards to identify areas of concern.
The ecological risk assessment concluded that the potential risk at Site 16/SSA 16 was driven
primarily by Aroclor 1260, aluminum, antimony, cadmium, and iron in the surface soil. For
comparative purposes, the detected concentrations of the inorganics were evaluated against
WPNSTA Yorktown background concentrations in soil and soil toxicity.benchmark values presented
in literature (see Table 8-2). The inorganics were detected at concentrations greater than the
maximum concentrations detected in the WPNSTA Yorktown background samples, and greater than
benchmark values obtained from the literature indicating that adverse effects from the detected
concentrations on soil organisms may potentially occur.
Detected concentrations of PCBs at Site 16/SSA 16 do not pose unacceptable risks to human health
or the ecology. PCBs were, however, detected in the surface soil samples at Site 16/SSA 16 at
concentrations ranging from 34 ug/kg to 3,040 ug/kg. The DoN evaluated whether these levels
warranted remediation. With respect to the protection of human health, the PCB concentrations
were evaluated against the USEPA guidance for the cleanup of PCBs under CERCLA. The guidance
(which is not a regulation) suggests that PCBs be remediated to 1,000 ug/kg (or 1 part per million
[ppm]) for residential areas, and between 10 ppm to 25 ppm for industrial areas. Since the detected
concentration of PCBs at Site 16/SSA 16 was not determined to present an unacceptable current or
future human health risk, and since the maximum detected PCB concentration (i.e., 3 ppm) is below
the suggested remediation limit for industrial areas (10 ppm to 25 ppm), remediation of the PCBs
did not appear to be warranted for this site for the protection of human health. In addition, the
institutional controls included with the selected remedy for Site 16/SSA 16 will restrict future
residential use of the area. It is anticipated that the future land use of this area will be for industrial
purposes.
8-3
-------
With respect to ecological concerns, the detected PCB levels were evaluated against benchmark
values for effects on terrestrial flora and fauna. Adverse effects were noted in earthworms and
invertebrates. There is uncertainty in assessing the terrestrial environment using these benchmark.
values. Various inorganics in surface soil have a high degree of variability. The high degree of
variability of inorganic concentrations in surface soil in turn magnify the uncertainty associated with
using literature toxicity values to assess potential risk posed to the terrestrial environment. Based
on this evaluation, remediation of the PCB soil did not appear to be warranted for the protection of
the environment.
Therefore, based on the above-mentioned information, no areas of concern were identified for the
surface soil at Site 16/SSA 16 and no remedial action other than institutional controls was deemed
necessary.
8-4
-------
SECTION 8.0
TABLES
-------
TABLE 8-1
SUMMARY OF CRITERIA AND RISK-BASED VALUES
APPLICABLE TO THE GROUNDWATER COPCs FROM THE ROUND TWO RI
SITE 16 AND SSA 16
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Groundwater
Contaminant of Potential
Concern
Groundwater Criteria0'
Federal
MCL
(ug/L)
Virginia
PMCLs
(ug/L)
Remediation Goal
Options
(ng/L)(2>
VOLATILE ORGANICS
1,1-Dichloroethene
1,1-Dichloroethane
1,1,1-Trichloroethane
Trichloroethene
Tetrachloroethene
7
„(')
200
5
5
7
-
200
5
-
1,560
SEMTVOLATDLE ORGANICS
1 ,4-dichlorobenzene
75
' -
PESTICEDES/PCBS
Aldrin
Endrin
4,4'-DDT
-
2
—
-
0.2
—
0.47
7.82
INORGANICS
Aluminum
Antimony
Arsenic
Beryllium
Chromium
Manganese
Vanadium
-
6
50
.4
100
50<4>
—
-
-
50
-
50
50«>
-
15,600
110
Maximum Detected
Concentration
(ug/L)
Total
Dissolved
Locations that
Exceed the
Criteria
2
1
7
0.7
0.6
2
1
7
0.7
0.6
None
None
None
None
None
2
2
None
0.043
0.02J
0.058
16,600
NDM*)
21.4
0.93
41.4
146
36
0.043
0.02J
0.058
None
None
None
17
19.3
5.9
0.34
1.6
114
2.7
16GW01
16GW05
None
None
None
16GW04
16GW07
16GW09
None
Notes:
(1) Federal MCL - Federal Safe Drinking Water Act Maximum Contaminant Level (USEPA, November 1994;
Drinking Water Regulations and Health Advisories) and Virginia Drinking Water Standards - PMCLs - Primary
Maximum Contaminant Levels (Bureau of National Affairs, December, 1994).
(2) Remediation Goal Options were established for the COPCs that did not have an existing Federal MCL or
Virginia PMCL. They were based on an ICR = 1 x 10"04 and an HI = 1.0. The most limiting (conservative) risk-
based value is listed on the table. These values were developed in the RI for Site 16/SSA 16.
0) „ = No criteria published.
(4) Federal SMCL = Secondary Maximum Contaminant Level, not a promulgated standard.
(S) ND - Not detected.
(6) Antimony (total fraction) was detected during the Round One RI at a concentration of 48.3 ug/L.
-------
TABLE 8-2
SUMMARY OF INFORMATION USED TO EVALUATE AREAS OF CONCERN
WITH RESPECT TO THE ECOLOGICAL RISK ASSESSMENT
SITE 16 AND SSA 16
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Primary Surface Soil
Ecological Contaminant of
Concern
Pesticides/PCBs (ng/kg)
PCBs (total)
Inorganics (mg/kg)
Aluminum
Antimony
Cadmium
Iron
Soil Flora and Fauna
Toxicity Values'"
Plant
40,000
50
5
3
100(2)
Earthworm
40®
NE
NE
20
NE
Invertebrate
40«
NE .
NE
3
3,515
Microorganisms
and Microbial
Processes
NE<»
600
NE
20
200
Range of Positive
Detections
34 - 3,040
4,280 - 9,220
9 - 63.8
0.62 - 66.5
5,240-217,000
(l) Will and Suter, 1994a and 1994b unless indicated otherwise (Values presented for plants, earthworms, and
microorganisms and microbial processes are benchmarks below which adverse impacts to these species
are not expected. Values for invertebrates are No Observed Effects Concentrations; however, they are
based on less data than the benchmarks)
w USEPA, 1995a (Region III BTAG Soil Screening Levels for Soil Fauna)
w NE = Not Established
ug/kg = micrograms per kilogram
mg/kg = milligrams per kilogram
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9.0 Explanation of Significant Changes
The Final PRAP for Site 16/SSA 16 was released for public comment in July 1995. The PRAP
identified the No Further Remedial Action Decision as the preferred alternative. USEPA Region III
provided comments on the Final PRAP suggesting that institutional controls be added to the No
Further Remedial Action Decision to insure the future protection of human health and the
environment. USEPA suggested that the institutional controls include methods to insure that future
residential land use of Site 16/SSA 16 will be controlled by the DoN. Based on USEPA's comments,
the selected remedy for Site 16/SSA 16 was changed from the preferred alternative presented in the
PRAP to include land-use and aquifer-use restrictions at the site.
9-1
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10.0 RESPONSIVENESS SUMMARY
The selected remedy for Site 16/SSA 16 is the No Further Remedial Action Decision with
Institutional Controls. Based on written comments received during the Public Comment Period and
the Comments received from the audience at the Public Meeting on August 23, 1995, the public
appears to support the preferred alternative.
The transcript of the Public Meeting is provided in Appendix A. Navy responses to comments
provided during the Public Comment Period are provided in Appendix B.
10.1 Background on Community Involvement
As part of the requirements of the Community Relations Program, community interviews were
conducted from July 29 to August 1, 1991. These interviews were conducted to inform the
community, primarily through elected officials, public agencies, interest groups and concerned
citizens, of the IR Program and the sites at WPNSTA Yorktown. The interviews also were
conducted to obtain feedback from the community at large on the perception of WPNSTA
Yorktown, and on the reaction concerning the possibility that WPNSTA Yorktown would be placed
on the National Priorities List (NPL) as a Superfund Site.
A total of 26 individuals were interviewed. The WPNSTA Yorktown Public Affairs Officer
interviewed additional citizens. Attempts were made to speak with a wide variety of individuals
representing local and Commonwealth government, community groups, and educational groups.
Citizens representing the area closest to the station, the community of Lackey, were also
interviewed. -The following is a breakdown of the types of interview participants: public officials,
station personnel, station residents, media representatives, community/environmental groups, local
off-station residents, and local business persons.
Prior to 1995, public input on environmental activities was provided by a Technical Review
Committee (TRC). In order to generate more involvement from the general public, the TRC was
replaced by a Restoration Advisory Board (RAB) on March 16,1995. The RAB meets quarterly to
discuss ongoing activities and issues at WPNSTA Yorktown. The Public Meeting for
Site 16/SSA 16 was conducted in conjunction with a RAB meeting.
10-1
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During the Public Meeting, three RAB members asked questions in regard to surface water and
groundwater conditions at Site 16/SSA.16. These questions were answered to the satisfaction of the
RAB members during the meeting (refer to Appendix A - Public Meeting Transcript).
10-2
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APPENDIX A
TRANSCRIPT OF PUBLIC MEETING - AUGUST 23,1995
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1 PROPOSED REMEDIAL ACTION PLAN (PRAP)
2
3 PUBLIC MEETING for OPERABLE UNIT
4 (OU) II (SITE 16/SSA 16)
5 RESTORATION ADVISORY BOARD (RAB) MEETING
6
7 FOR THE INSTALLATION RESTORATION PROGRAM (IRP)
8 NAVAL WEAPONS STATION YORKTOWN
9 YORKTOWN, VIRGINIA
10 YORK COUNTY SOCIAL SERVICES/RECREATION CENTER
11 301 GOODWIN NECK ROAD
12 23 AUGUST 1995
13 6:30 P.M. - 8:30 P.M.
14
15 PRAP PRESENTATION SPEAKER:
16 DONALD C. SHIELDS
17
18 US GEOLOGICAL SURVEY FRAMEWORK STUDY OVERVIEW SPEAKER:
19 ALLEN BROCKMAN
20
21 COMMENTS/ANNOUNCEMENTS OF FUTURE MEETINGS SPEAKER:
22 JEFF HARLOW
23
24 REPORTING SERVICES PERFORMED BY:
25 MICHELLE ANTHONY
MICHELLE ANTHONY & ASSOCIATES
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1 PRAP MEETING
2
3 MR. BLACK: Our new commanding officer
4 is not able to be here tonight. He's up in a so-called
5 Board of Directors Meeting for the Naval Ordinance
6 Center in Maryland. Our Executive Director, Bruce
7 Doubleday, is carrying his luggage up there for him I
8 guess. He's in attendance there as well..
9 Captain Delaplane had a change of
10 command on the 27th of June. So Captain Denham is the
11 new commanding officer right now. I'm not certain
12 whether he will designate himself to be the co-chair
13 here or —
14 MRS. NEILL: He has Tom.
15 MR. BLACK: He has? Last I heard it
16 was either he or Bruce. So right now Carolyn Neill, who
17 is head — our environmental director is sitting in as
18 the Navy's co-chair. He's gotten appointed at least for
19 tonight.
20 We have one new member here. This is
21 the first time he's made it. Primarily, because we've
22 changed the meeting date from Thursday to Wednesday.
23 That's Yancey McGann down on the corner down there. If
24 y'all don't know Yancey, he's a former Executive
25 Director at the Weapons Station Yorktown, been there
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
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1 longer than I have, in fact; but retired last April the
2 1st, April Fool's day, he retired. So welcome to him
3 for being here, and y'all excuse me please.
4 What else was I supposed to say, Jeff?
5 I can't remember. I think that's it anyhow, but I'm
6 going to introduce Don Shields now. Don's going to give
7 a presentation on this board that we have been looking
8 at over here for the Proposed Remedial Action Plan on
9 Site 16, which is the West Road Landfill and Site
10 Screening Area 16, which is a scrap metal dump that we
11 used to have down near Building 402 on this station.
12 So without further ado, Don, I'll let
13 you go at it.
14 MR. SHIELDS: Thank you, Mr. Black.
15 Again, Mr. Black we at Baker Environmental really
16 appreciate the opportunity Alantic has given us to work
17 down here at Weapons Station and have the opportunity to
18 come out tonight and present our results.
19 Could we get those lights too, Tim,
20 please. And thank you all for coming out to hear us
21 give our presentation on the results of the work we have
22 been doing at Site 16 and Site Screening Area 16.
23 For those of you who were at the last
24 RAB Meeting, we had — you'll probably recall this. We
25 gave a presentation oh the work we had been doing at
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
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1 these sites at that time. Tonight's presentation is
2 part of the public meeting that's required now that the
3 Navy has proposed it's remedial plan for this site.
4 Because I know you have a full agenda this evening,
5 we're going to go through this a little quicker than we
6 did last time, and because you've had a chance to hear
7 this presentation before.
8 We'll briefly touch on the background
9 of the site, the Removal Action that was conducted at
10 the site in 1994, some of the previous investigations
11 including this most recent Remedial Investigation and
12 the Risk Assessment work that has been done there, and
13 spend a little more time on the Proposed Plan for
14 Remedial Action at Site 16 and Site Screening Area 16
15 that the Navy is proposing tonight.
16 Hopefully, you've had a chance to look
17 at the posters that are up. Anything that's going to be
18 presented tonight is — that information is presented on
19 those posters and also in some of the other documents
20 that you have received, such as the Proposed Remedial
21 Action Plan, the RI Report, some of the things the RAB
22 members have gotten executive summaries for.
23 For those of you who were here at our
24 last meeting, you will recall Site 16 is a fairly small
25 site. It was used as a Surface Dumping Ground or dump
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
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1 site during the 1950's and the 1960's for a wide variety
2 of things, mostly scrap material, batteries, 55-gallon
3 drums, general scrap refuse as listed up here was dumped
4 on the surface there. There are some pictures of that
5 on the one poster board that we have this evening.
6 This is an aerial photo that shows a
7 couple of things. North is to the top of the screen.
8 To get you folks oriented, this is Lee Pond, Lee Road,
9 Main Road, and West Road; which the West Road Landfill
10 was named for. That's site 16. This is the Hunt Shack
11 and the archery range that those of you who have been to
12 Site 16 probably recall, and Site 16 is this wooded area
13 right along here/ and overlapping the northern part of
14 it is Site Screening Area or SSA 16, which is the old
.15 metal scrap yard. This is an eastern branch of Felgates
16 Creek.
17 Site Screening Area 16 was also covered
18 in this investigation that we've done. Most of you that
19 are involved in the RAB understand that the Site
20 Screening Area is a former Solid Waste Management Unit
21 or an area of concern that the Navy has agreed to
22 subject to a screening process to determine whether or
23 not a full pledged RI/FS or Remedial Investigation
24 Feasibility Study process is required for that site.
25 Because Site 16, because Site Screening
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
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1 Area 16 or SSA 16 overlies the northern portion of Site
2 16, they were lumped together and investigated in one
3 group over the past year.
4 Site Screening Area 16, the building
5 402 Metal Disposal Area, is also a small site. It is
6 only an acre in size it overlies the northern portion of
7 site 16 and mostly scrap metal and some empty drums and
8 other material of that nature was disposed of there.
9 This is an aerial photo that shows Site
10 screening Area 16 in close-up. This is a view that's
11 opposite to the last photo you saw or any of the maps
12 that you have probably seen for the sites. We're
13 looking south this time. Here's Lee Pond down here or
14 up here, excuse me. Lee Road, West Road and this gives
15 a good close-up view of Site" Screening Area 16. This is
16 where the scrap metal was piled up at one time, and it
17 has since been removed, not as a Removal Action, but as
18 a general housekeeping action that has taken place by
19 the Bay Station.
20 Site 16 would be located down in this
21 wooded area right along in here. Here's the archery,
22 the open archery area Site 16 and the Hunt Shack would
23 be just off the — out of the photo. Mr. Harlow didn't
24 lean out of the helicopter far enough when he was taking
25 it or we would have picked up the Hunt Shack in the
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
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1 photo.
2 Site 16 and all of the other sites at
3 the Weapons Station have been investigated from an
4 environmental perspective. It's been — they have been
5 put through a battery of investigations over the past
6 ten years. These include an Initial Assessment Study,
7 which was a base-wide study to determine what sites
8 might need actual work done at them.
9 Confirmation studies, which after those
10 sites were selected people — contractors went out and
11 actually collected samples, Biological Sampling and Risk
12 Evaluation was done on the streams and Lee Pond to
13 determine the risks that had to do with the consumption
14 of fish and shellfish at the Weapons Station, but the
15 investigation that started focusing in on Site 16
16 proper, which we are going to talk about tonight,
17 started in 1992 when a Round I Remedial Investigation
18 was conducted.
19 We went into that in pretty good detail
20 during the last RAB Meeting. The Round I Remedial
21 Investigation, which was conducted back in '92, included
22 soil, groundwater, surface water, and sediment samples.
23 The results of that investigation indicated that in
24 order to fully complete a Human Health Ecological Risk
25 Assessment, that additional data was going to need to be
MICHELLE ANTHONY & ASSOCIATES
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1 collected.
2 Well, after the Round I had taken
3 place, but before any further additional investigation
4 work was done, the Navy proceeded with a Removal Action
5 at Site 16. The batteries and the scrap metal and
6 ordnance and all of those sorts of things were removed
7 from the surface of Site 16 last year.
8 The poster that the Navy provided on
9 the side has, again, some good photos of the material
10 that's been removed and also includes the before and
11 after photo of the Removal Action.
12 At the last meeting, Greg Hatchett from
13 LANTDIV had a video here, and it went through the
14 Removal Action process at the sites on the Weapons
15 Station, and there was some footage of the work done at
16 Site 16 at that time.
17 As well as after the Removal Action was
18 completed and all the scrap materials taken away,
19 samples were collected of the surface soil in order to
20 evaluate how successful that was in removing the sources
21 of contamination, the potential contamination at Site
22 16. Those are referred to as Confirmation Samples or
23 Surface Soil Confirmation Samples. And that's important
24 because in the subsequent work that we have done, over
25 the last year, the Round II Remedial Investigation, that
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1 data has been put to work again and used as part of that
2 data set.
3 The Round II Remedial Investigation was
4 conducted, the field work was initiated for that last
5 summer after the Removal Action was completed. This
6 public meeting is part of that project, that Round II
7 Remedial Investigation and subsequent other documents
8 that we have been working on and providing to you.
9 The Round II Remedial Investigation
10 included collection of soil, groundwater, surface water,
11 and sediment samples. In addition to that, fish and
12 benthic macroinvertebrates were collected. Benthic
13 macroinvertebrates is a fancy word for bugs and worms
14 that live in the streams that are down in the sediment.
15 In addition as I mentioned, the
16 confirmation samples that were collected during the
17 Removal Action were also incorporated as part of that
18 data set for the Round II Remedial Investigation. All
19 the data we generated was compared to background
20 results, and at our last meeting Rich Hoff from Baker
21 presented a brief talk on what the background
22 investigation was about at Weapons Station.
23 Basically, it involves collecting
24 samples in areas that are located far away from the
25 sites of concern to determine what the soil,
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach,. VA (804) 486-2487
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10
1 groundwater, surface water, and sediment are naturally
2 away from any man-made impact. For instance as we know,
3 as we have talked about before, lead occurs naturally in
4 soil. We need to be able to tell whether or not lead we
5 find in the soil samples at one of our sites is due to
6 the natural nature of the material or if it has to do
7 with something from, like, paint or batteries that have
8 been disposed of at a site. All the data we generated
9 during the Round II RI was compared and evaluated
10 against that background data set.
11 The main purpose of collecting all the
12 data and all the evaluation associated with the Round II
13 Remedial Investigation is to basically conduct a Human
14 Health and Ecological Risk Assessment to determine
15 whether or not there are any risks associated with Site
16 16 or Site Screening Area 16.
17 For the Human Health Risk Assessment,
18 we grouped those — we conduct that — we group
19 potential folks that could be affected by the site into
20 four different groups or what we call scenarios. That
21 would include on-site adult workers, folks that may be
22 out and about on the site doing maintenance of some kind
23 or another as part of the land management.
24 We've also constructed this Risk
25 Assessment model assuming that if there was a housing
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836 Westminster Lane, Virginia Beach, VA (804) 486-2487
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11
1 development that was set up on Site 16 or SSA 16, what
2 would the impact be to long-term resident adults or
3 resident children if they were out on the site as it
4 stands now, and another model was for construction
5 workers that might be doing any building activities out
6 there in the future.
7 The results of the Human Health Risk
8 Assessment are the following: There are no immediate
9 threats to human health from the media at 16 or Site
10 Screening Area 16. There are some possible threats to
11 long-term residents if the site were to be used for
12 housing. That's a very conservative — that's according
13 to a very conservative scenario.
14 The risk is driven mainly by arsenic,
15 antimony, and manganese in the shallow groundwater that
16 is underneath the site right now. These are chemicals
17 that occur naturally and were detected in the
18 background, in the background study, and it's also
19 important to note that the shallow aquifer is not used
20 in this area as a water supply due to its low yield and
21 its poor quality.
22 And the quality has nothing to do with
23 any kind of contamination or anything like that. It's
24 just the shallow groundwater just doesn't pump at a very
25 high rate, it's muddy, et cetera; and it just doesn't
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12
1 provide a good, clean water supply, so it's not
2 something that's generally used in this area.
3 The Ecological Risk Assessment was
4 conducted on surface soil and surface water and sediment
5 in the vicinity of Site 16 and SSA 16. The aquatic and
6 terrestrial environments, i.e. water up on the land,
7 were both evaluated, and it was determined that there
8 was no unacceptable risk to the environment based on the
9 results of the Round II Investigation.
»
10 One of the other things that Greg
11 Hatchett talked about at the last meeting was the CERCLA
12 Process, CERCLA or Superfund Process, how we go through
13 evaluating these sites. The Navy also has a process
14 that is referred to as the Installation Restoration
15 Process, and the Navy's designed that to mirror the
16 CERCLA Process.
17 I put this up so we could see where the
18 Remedial Investigation and some of the work we have been
19 doing at Site 16 and SSA 16 fits in with this process.
20 At first, we go out to the site, collect, get our data,
21 get a grip on what the nature and extent of
22 contamination and potential risks might be to human
23 health and the environment at this site. That's the RI
24 or the Remedial Investigation.
25 After that is done, a Feasibility Study
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836 Westminster Lane, Virginia Beach, VA (804) 486-2487
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13
1 is done, and what a Feasibility Study is, it takes areas
2 of concern or areas in contamination at the site, and it
3 evaluates what would be the best cleanup or Remedial
4 Action that could be conducted.-
5 If we had like an area, say the size of
6 in-between these tables here that the soil was
7 contaminated with a solvent, for instance, we might
8 evaluate digging up the soil and disposing of it in a
9 landfill or, digging up the soil and disposing of ;Lt in
10 an incinerator or something along those lines, and all
11 of those options are evaluated, and the pros and cons
12 and the costs and benefits of those are presented.
13 After that's been completed, the Navy
14 will select its Proposed Remedial Action Plan or PRAP of
15 all those remedies that were talked about in the
16 Feasibility Study. It picks the one that it feels is
17 the best in accordance with all the criteria that Greg
18 went over last week, and when that's finally completed
19 and there has been public input to that, a Record of
20 Decision is signed, and that's the final document. The
21 decision is signed off on how one of these sites are
22 going to be handled.
23 Site 16 and Site Screening Area 16 are
24 a little bit different than that. Because we found no
25 immediate threats to human health through the
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environment, and there were really no areas of concern
that we could go out and put a hand on a site, like,
this is a site of contaminated soil or this is a plume
of contaminated groundwater, there was really no area of
concern that needed to be evaluated, or where we had to
pull out all of these remedial options and weigh them
against each other.
So what the Navy has done is, they have
went past the Feasibility Study stage. A Feasibility
Study wasn't done for Site 16 and Site Screening Area
16, but they move directly into their Proposed Remedial
Action Plan, and the Proposed Plan for Site 16 and site
Screening Area 16 is as follows: The plan is no further
Remedial Action with Institutional Controls.
Now, that has two parts to it. The no
further Remedial Action part says that no further
Remedial Action is necessary because the Removal Action
that removed all the material that had been dumped there
on the surface has been successful in removing sources
of potential contamination which might _af feet human
health or the environment.
The Institutional control part has to
deal with the fact there were some, according to these
conservative models, some potential risks associated
with long-term residencies at the site if it were ever
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to be used in the future as a residential complex.
Those sort of controls on land use and water supply use
are in ~ on non federal facilities are done through
deed restrictions. On a federal facility such as this/
it would most likely be done through their master plan.
As you may recall at the last meeting
when we made this same presentation, the Proposed Plan
was just no further Remedial Action at that time. The
Institutional Control part is something that the _Navy
has agreed to add on to that based on comments they have
since received on some of their draft documents from the
United States Environmental Protection Agency/ but it's
not just the Navy and the Environmental Protection
Agency or the Commonwealth of Virginia, folks, that are
the only ones that has say in this. The public has
input on the selected remedy as well.
And to conclude tonight/ I will just
touch on these few points: The public is always
encourage to participate in the decision-making process/
and you have several opportunities to do that.
We're right now in the middle of a
formal public comment period that's require under the
CERCLA Process, and that was announced in the local
newspaper.
This public meeting that we're here
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tonight for is part of that. Comments can be submitted
on this plan, either verbally this evening in the form
of questions or otherwise commenting to the folks from
LANTDIV or Mr. Black from the station. We can have
also — you can also submit your comments in a written
form.
If you had a chance on your way in, you
may have noticed that there has been a fax sheet/ which
is a good plain-language summary of some of these things
we have been talking about tonight, and there is
information in there on public participation, not only
about the repositories where all the information is
stored, but on ways you can contact Mr. Black
specifically in order to provide any comment to him that
you may have on any aspect of this particular project.
When all of those comments, either the
verbal ones tonight, which are going to be recorded by
the stenographer or anything that is written is provided
to Mr. Black, those are all responded to in what's
called a Responsiveness Summary. That's a section of
the final Record of Decision or ROD. Those of you who
may receive draft versions of a Record of Decision,
you'll see a Section 11, which says Responsiveness
summary.
It's blank for now because we haven't
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had public comments yet. That's what we're getting
tonight/ and when those are responded to/ those will be
put in the final Record of Decision, which is signed off
on by the Navy and the us EPA, and that's the end of my
talk this evening.
Jeff/ I don't know if you want to go to
break or if you have questions that we'll be happy to
answer them.
MR. HARLOW: Questions and answers.
MR. SHIELDS: Mr. Black?
MR. BLACK: I agree.
MR. HARLOW: If there are no questions
we can take about a ten minute break.
MRS. ROGERS: Does the Biological
sampling that is done at this particular site/ is that
interrelated to any other Biological Sampling of any
other site that is impacted on/ say/ Felgates Creek?
MR. SHIELDS: At this time/ it is part
of a data base —
MRS. ROGERS: Okay.
MR. SHIELDS: — that eventually will.
This is the first one of the Round II Remedial
investigations that have been done. For instance, Site
12, site 6 and 7 and a whole host of other sites are in
the pipeline in different stages. This was the first
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18
1 one to cross the finish line so to speak and get to this
2 stage, but that's part of the data base that's going to
3 be available to the EPA, the state, and the public in
4 order for them to evaluate things like Felgates Creek,
5 et cetera over time.
6 MR. HOFF: Don, if I may?
7 MR. SHIELDS: Yeah, sure, Rich.
8 MR. HOFF: One of the things that EPA
9 has stressed is trying to stay away from a snapshot
10 understanding of what's going on.
11 MR. SHIELDS: Rich, you're going to
12 have to speak up.
13 MR. HOFF: One of the things EPA has
14 stressed is to try to stay away from the snapshot
15 evaluation of a habitat or a' potential ecological risk.
16 What we're doing right now is, we compile this
17 information. There are sites upstream and on Felgates
18 proper, and there are also downstream locations, such as
19 Lee Pond, that are in the pipeline, and they will be
20 evaluated.
21 And so what we'll be doing with those
22 is, we're looking at the data. We'll be checking to see
23 that there is potential for secondary sources and
24 migration of contamination to off-site areas, and so it
25 will be evaluated in more of a wholistic fashion as time
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19
1 goes by.
2 MR. SHIELDS: Yes, sir, may I have your
3 name for the stenographer?
4 MR. HAVEN: Site 16, you said the
5 groundwater was not quite acceptable for residential
6 development. Site 16, I guess, you said was maybe an
7 acre or —
8 MR. SHIELDS: It's about five acres in
9 size.
10 MR. HAVEN: Five acres. Now, in terms
11 of that five acre place wouldn't it be reasonable to
12 suppose that the groundwater has spread a little bit
13 backwardly? So a little bit more of the groundwater is
14 impacted other than five acres right underneath that
15 site?
16 MR. SHIELDS: Actually, not at this
17 site. The data that we had to use to put into this risk
18 model, we — no one well on our site had the same
19 contaminants twice. It was like a little bit here of,
20 like, arsenic, and then antimony in another one, and
21 manganese in another one. That's why we didn't have
22 what we call an area of concern.
23 There was no — there are strict
24 guidelines that are promulgated by the US EPA on how a
25 Human Health Risk is conducted that we have to follow,
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
-------
20
1 and so that's why when we say this, we say that it's a
2 conservative picture that we're presenting to you, but
3 there is no plume or there is no area we can draw a
4 circle on a map saying, okay, this is where our antimony
5 problem is. That's just not the case, and there are
6 wells surrounding that that indicates that there is no
7 sort of —
8 MR. DEWING: Let me ask a question so I
9 can clarify something. What depth were the samples, the
10 water samples taken, so-called wells?
11 MR. SHIELDS: I would say approximately
12 30 to 40 feet below the ground.
13 MR. DEWING: So a depth of 30-40 feet?
14 MR. SHIELDS: Yes, sir.
15 MR. DEWING:' Groundwater?
16 . MR. SHIELDS: Yes, sir.
17 MR. DEWING: Not down in the Yorktown
18 aquifer?
19 MR. SHIELDS: No, sir.
20 MR. DEWING: If my memory is correct,
21 York County does not allow groundwater wells anymore.
22 MR. SHIELDS: I am not aware of that,
23 sir.
24 MRS. ROGERS: Yes, they do.
25 MR. DEWING: Groundwater wells?
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
-------
21
1 MRS. ROGERS: You mean a well that I
2 would put in if I were .going to build a house and
3 couldn't get water?
4 MR. DEWING: You would have to go down
5 to the Yorktown aquifer like I am —
6 MRS. ROGERS: No, not in the north part
7 of the county. They just allowed 120 residencies on two
8 acres each that are going to have wells.
9 MR. DEWING: How deep?
10 MRS. ROGERS: I don't know.
11 MR. DEWING: That's the point.
12 " MRS. ROGERS: I don't know the depth.
13 I just know there are two wells that are already being
14 put in by the county they are running 250-275 feet.
15 MR. DEWING:- Okay. Fine that's not
16 groundwater.
17 MRS. ROGERS: That's what I was asking.
18 Yet 60 feet would be considered the groundwater up in
19 the upper part of the county.
20 MR. DEWING: You just said they are 200
21 and some odd feet.
22 MRS. ROGERS: These are the deep wells
23 that are going to .support the —
24 MR. DEWING: Well ~
25 MRS. ROGERS: But that's within a half
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
-------
22
1 mile of where the lots are going to be developed where
2 they are going to put the other wells. So I can't tell
3 you now.
4 MR. DEWING: Let me put it this way,
5 Betty, I'm not familiar with the rules in the north part
6 of the county, the northern end up there, but in this
7 part down here you cannot have a shallow well.
8 MRS. ROGERS: Uh-huh.
9 MR. DEWING: For family consumption, we
10 have to go down to the Yorktown aquifer. If you have a
11 well, you have to have a class 3 well rather than Class
12 2. So you know water at 10, 20, 30 feet is not really
13 even usable.
14 MR. SHIELDS: That's correct. Really
15 it would pump at such a low level you really couldn't
16 use it for —
17 MR. DEWING: That's a secondary point.
18 MR. HARLOW: Any other questions?
19 Let's us take a ten minute break, and we'll start the
20 RAB Meeting, and I'll do a couple items and introduce Al
21 Brockman.
22 (PRAP presentation was concluded.)
23
24
25
MICHELLE ANTHONY & ASSOCIATES
836 Westminster Lane, Virginia Beach, VA (804) 486-2487
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APPENDIX B
RESPONSE TO COMMENTS RECEIVED DURING
THE PUBLIC COMMENT PERIOD
-------
RESPONSE TO COMMENTS SUBMITTED BY TJSEPA REGION m
ON THE
DRAFT PROPOSED REMEDIAL ACTION PLAN
COMMENT LETTER DATED JULY 25,1995
SITE 16 AND SSA 16, NAVAL WEAPONS STATION YORKTOWN,
YORKTOWN, VIRGINIA
Specific Comments
1. Institutional Controls have been added to the proposed plan. The selected remedy for
Site 16/SSA 16 is now "No Further Remedial Action Decision with Institutional Controls."
The Final Record of Decision (ROD) reflects this.
2. Please refer to response to Specific Comment No. 1.
3. The shallow aquifer system within York County is comprised of the Columbia, Cornwallis
Cave and Yorktown-Eastover aquifers and their associated confining units. Potable water
sources from the shallow aquifer system are drawn from the Columbia and Yorktown-
Eastover aquifers. The Cornwallis Cave aquifer is not used as a potable water source due
to its limited yields. (Oral communication between Baker Environmental, Inc. and Terry
Wagner-Environmental Program Manager in the office of Groundwater Management-
VADEQ on July 17, 1995). This is also supported by D.L. Richardson's Report
"Hydrogeology and Water Quality of the Shallow-Groundwater System in Eastern York
County, Virginia" where it is stated that the Cornwallis Cave Aquifer is not used as a public
or domestic water supply.
The Final ROD includes a discussion of this information.
4. Please refer to response to Specific Comment No. 3.
5. Please refer to response to Specific Comment No. 1.
6. This will be noted in the Final ROD.
7. Please refer to response to Specific Comment No. 7.
-------
RESPONSE TO COMMENTS SUBMITTED BY THE BIOLOGICAL TECHNICAL
ASSISTANCE GROUP (STAG)
ON THE
DRAFT PROPOSED REMEDIAL ACTION PLAN AND
DRAFT RECORD OF DECISION
COMMENT LETTER DATED JULY 27,1995
SITE 16 AND SSA 16, NAVAL WEAPONS STATION YORKTOWN,
YORKTOWN, VIRGINIA
The selected remedy for Site 16/SSA 16 is the No Further Remedial Action Decision with
Institutional Controls. No sampling or long-term monitoring of any of the site environmental media
is proposed.
PCBs have been detected in low concentrations in site surface soils and in sediment samples in a
drainage ditch at the southern boundary of the site. It is important to note; however, that PCBs were
not detected in the downgradient sample locations in Felgates Creek in either the Round One (1992)
or Round Two (1994) Remedial Investigation. The potential for erosion of unacceptable
concentrations of PCBs from Site 16/SSA 16 into Felgates Creek proper is very low.
-------
RESPONSE TO COMMENTS SUBMITTED BY USEPA REGION m
ON THE
DRAFT RECORD OF DECISION
COMMENT LETTER DATED JULY 27,1995
SITE 16 AND SSA 16, NAVAL WEAPONS STATION YORKTOWN,
YORKTOWN, VIRGINIA
General Comments
1. Tables and Figures will be placed at the end of each section.
2. This information will be provided in tabular format in the Final ROD.
3. The text of the Final ROD has been restructured in response to this comment.
4. Changes made to the RI/BRA and Proposed Remedial Action Plan will be incorporated into
the Final ROD.
5. These figures have been added to the Final ROD.
6. Discussion of the Feasibility Study (FS) in Section 8 is limited to the rationale for not
conducting a FS.
Specific Comments
1. Institutional controls have been added to the Proposed Plan. The selected remedy for
Site 16/SSA 16 is now "No Further Remedial Action Decision with Institutional Controls."
The Final ROD reflects this.
2. The text has been modified in accordance with this comment.
3. Please refer to response to Specific Comment No. 1.
4. Please refer to response to Specific Comment No. 1.
5. The title of this section has been changed from "Types of Contamination" to "Identified
Contaminants of Concern." Please refer to response to General Comment No. 3.
6. Please refer to response to Specific Comment No. 1.
7. Please refer to responses to General Comment No. 4 and Specific Comment No. 1.
8. This section has been modified to include a discussion of the Institutional Controls that are
now included in the selected remedy in response to unacceptable risks to human health in
the future child resident scenario.
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RESPONSE TO COMMENTS SUBMITTED BY USEPA REGION m
ON THE
DRAFT REMEDIAL INVESTIGATION REPORT
COMMENT LETTER DATED AUGUST 8,1995
SITE 16 AND SSA16, NAVAL WEAPONS STATION YORKTOWN,
YORKTOWN, VIRGINIA
General Comments
1. A QA/QC Report will be submitted to EPA prior to submittal of the Final Record of
Decision (ROD).
2. Based on consultations with EPA personnel, a Monte Carlo simulation will not be
performed.
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JUL-27-1995 10:58 EPA REG 3 HUMD P.06/07
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 01
841 Chestnut BuMng
PhBacWphia, PernByfcanta 19107
Office ofSuperfund Direct Dial (21S) 587-1110
Robert Thomson, PJE. FAX (215) 587-0890
Man Code 3HW71
Date: July 25,1995
Ms. Brenda Norton, PE
AHantic Division, Naval Facilities Engineering Command
Environmental Quality Division
Code: 1822
Building N 26, Room 54
1510 Gilbert Street
Norfolk, Va 23511-2699
Re: Naval Weapons Station, Yorktown, Va.
Site 16 and Site-Screening Area 16
Review of draft final Proposed Plan
Dear Ms. Norton:
The U.S. Environmental Protection Agency (EPA) has completed its review of the Navy's draft final
Proposed Plan for Site 16 and Site-Screening Area (SSA) 16, located at the Naval Weapons Station -Yorktown
NPL site (WPNSTA), and we offer the following comments:
Specific Comments
1) Page 10. last paragraph
Please note that there are calculated HI values of 1.8 and 52 for future adult and child residential
scenarios at Site 16/SSA 16. For systemic toxicants, the acceptable exposure level, Le. total HI < 1,
has been exceeded for the adult and child residential scenario at Site 16/SSA 16. For the child
residential scenario, surface soil contributed an HI value of approximately 2 to the total HI value of
53 for Site 16/SSA 16. Therefore, in light of the statement that no further actions will be taken at
Site 16/SSA16, the systemic toxicant exposure level to surface soil at Site 16/SSA 16 under the child
residential scenario is unacceptable under the NCP (40 CFR ft 300.430[eJ).
Please note that EPA cannot concur with the 'no further action scenario* without institutional
controls being implemented for Site 16/5SA16, given the exceedances outlined above. Institutional
controls should be included in the final Proposed Plan and Record of Decision for Site 16/SSA 16. EPA
has previously requested that a paragraph be added to the final Proposed Plan describing the
institutional controls proposed for implementation at Site 16/SSA 16. Such mechanisms could include:
(1) Maintaining the existing fencing and continued use of existing security measures at the WPNSTA;
(2) Addition of language to the WPNSTA Master Plan describing the institutional control of the
future residential use of Site 16/SSA 16, etc.
2) Page 11.3rd paragraph
The statement "~.ir highfy unlikely given Us location within restricted area of the Station and the newty-
construcud security fence that encloses the restricted area..' is fine (See comment 1), however an
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JUL-27-1995 10=59
EPA REG 3 HUMD
P.07/07
additional statement needs to follow describing the mechanism, Le. institutional control(s), that will
be used to insure that future residential use of Site 16/SSA 16 is restricted. Such institutional control
measures serve to alert future users to the residual risks present at Site 16/SSA 16.
3) Paee IS. 1st paragraph
The rationale behind this paragraph is not well stated, nor is the conclusion supported. Please modify
the paragraph, or delete it from the final version.
4) Page 19. 2nd paragraph
This paragraph should be modified, emphasizing whether the use of the aqulfer(s) at Site 16/SSA 16
are restricted by the State of local government
5) Page 20. 3rd paragraph
With a HI of approximately 10 for surface soil and a total HI of 53 under the child residential
scenario, EPA disagrees with this conclusion, given no institutional controls.
6) Table 1
Please include the fact that Table 1 includes confirmation campling data from the Removal Action
in the footnote.
Please, if appropriate, include a footnote stating that Table 4 includes confirmation campling data
from the Removal Action.
This completes EPA's review comments on the draft final Proposed Plan for Site 16/SSA 16, located
at the WPNSTA. If you have any questions, please feel free to call me at (215) 597-1110,
Sincerely,
Robert Thomson, PE
VA/WV Superfund Federal Facilities (3HW71)
cc Steve Mihalko (VDEQ, Richmond)
Jeff Harlow (WPNSTA, Code 09E)
Paul Leonard (USEPA, 3HW71)
Nancy Rios (USEPA, 3HW13)
Bruce Rundell (USEPA, 3HW13)
Bob Davis (USEPA, 3HW13)
TOTflL P.07
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ftUG-01-1995 08=54 EPA REG 3 HUMD P-02
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION II
841 Chestnut BuUng
PHadeipNa, Pemsyfcarto 19107
SUBJECT: Yorktown NWS: PRAP and Draft ROD for DATE: 7-27-95
OU-2, Sita 16, and Site Screening Area
16
FROM: Robert S. Davis, Coordinator (3HW13)
Biological Technical Assistance Group
TO: Robert C. Thomson, RPM (3HW71)
Va./W. Va. Fed. Fac. Sect.
The BTAG has reviewed the PRAP and offers the following comments on
behalf of the FWS, NOAA, and EPA members.
Data from the RI indicate that substantial contamination has not
been transported from the site to drainage ditches via groundwater,
sediment, or surface water. At some locations in the drainage,
ditch and tributary to Felgates Creek, concentrations of
contaminants slightly exceeded their ERL screening guidelines,
indicating that some off-site migration of contaminants may have
occurred, or may presently be occurring. However, the site does
not appear to present a substantial threat to ecological receptors,
although there are protective measures that should be taken to
ensure that migration of contaminants from the soil into surface
water bodies will not pose a threat to aquatic organisms in the
future.
Overall, the PRAP did not address the risk to aquatic organisms via
contaminant migration, nor did it present a clear rationale for
eliminating areas of concern for terrestrial organisms exposed to
surface soil contamination. Evaluation of any potential for risk
may be folded into monitoring plans recommended below.
The following are recommendations which, if followed, should
clarify the overall conclusions made in the PRAP and address the
issue of protection of aquatic resources downstream from the site:
The PRAP should provide a rationale as to why remedial action
is not considered necessary when concentrations of both
inorganic substances and PCBs in soils were higher than
benchmark values and observed effects concentrations for
terrestrial organisms.
After the removal action, surface soil sampling was conducted
throughout the site. Two of the soil samples collected from near
the drainage ditch contained elevated concentrations of
-------
flUG-01-1995 08:54 EPfl FSB 3 HUMD P.03
contaminants (these data were presented in the Round Two Rl Report
April 1995).
At 16SS110, a location that appears to be very close to the ditch,
the following contaminants were detected: cadmium at 66.5 mg/kg;
copper at 1,440 ng/kg, zinc at 1,060 mg/kg, and PCBs at 3.0 mg/kg.
In addition, soil screening using immunoassay for PCBs during the
removal action sampling showed 6 of the 11 samples screened
measured positive for PCBs, with five of the positive detections
located in the reach from the origin of the drainage ditch to
approximately 22 meters south along the drainage ditch. In the
PRAP, it was stated (pg. 6) that this potential source area was
later addressed and evaluated during the Round Two RI. However,
this area was not represented by any of the Round Two sampling
locations.
This area may be a source of contamination to the drainage ditch if
there is a potential for erosion, or if surface water or
groundwater infiltrates through the soil and migrates into the
ditch, but it does not appear that this potential source of
contamination has been adequately addressed. To ensure protection
of aquatic organisms, additional sampling should be conducted in
this area to fully identify the nature and extent of contamination
and the potential for transport of contaminants into the ditch.
Based on the results, removal or containment of soil near the ditch
may be needed, but the sampling effort can become part of the
monitoring plans, at least initially.
While the level of contamination at Site 16 is relatively low when
compared to available guidelines and criteria, some concern is
raised over the location of sediment sample number 16SD07. This
location may be receiving low levels of contamination from the
site. We previously recommended that additional sampling should be
considered to determine whether results from 16SD07 represent a hot
spot of contamination, or whether the contamination in this area is
more widespread. A judgement can be made to include this either as
a individual effort or as part of the monitoring plans.
We also recommend some long-term monitoring at those locations
where contamination has been identified. This can be planned for
coordination with monitoring at other sites in the facility so that
extra efforts do not have to be mounted. In addition, the
monitoring can be carried out once every five years rather than
every year. Finally, monitoring can be justified on the grounds
that action has already been taken in the form of removal.
This concludes BTAGs comments on the PRAP and Draft ROD for Site 16
and SSA 16 located at the Naval Weapons Station - Yorktown.
TOTftL P.03
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JLL-27-1995 10:55 EPfl REG 3 HUMD P.02/07
(•••*% UNTTED STATES ENVIRONMENTAL PROTECTION AGENCY
" '** REGION 01
841 Chestnut Bidding
Phiadekfta, Pennsylvania 19107
Office of Superfund Direct Dial (215) 597-1110
Robert Thomson, P.E FAX (215) 597-9890
Mai Code 3HW71
Date: July 27,1995
Ms. Brenda Norton, PE
Atlantic Division, Naval Facilities Engineering Command
Environmental Quality Division
Code: 1822
Building N 26, Room 54
1510 Gilbert Street
Norfolk, Va 23511-2699
Re: Naval Weapons Station, Yorktown, Va.
Site 16 and Site-Screening Area 16 .
Review of draft Record of Decision
Dear Ms. Norton:
The U.S. Environmental Protection Agency (EPA) has preliminarily reviewed the Navy's draft Record
of Decision for Site 16 and Site-Screening Area (SSA) 16, located at the Naval Weapons Station - Yorktown
NPL site (WPNSTA), and we offer the following comments:
General Comments
1) Please incorporate tables and figures into the text of the draft revised Record of Decision, where
appropriate, instead of placing them at the end of the document
2) Throughout the draft Record of Decision, there are vague descriptions of the concentrations of
chemicals detected at Site 16 and SSA 16, such as '-relatively low concentrations^.' or '^.concentrations
are typical of concentrations found.*' instead of listing specific concentrations or concentration ranges.
Please use specific concentrations or concentration ranges in the draft revised Record of Decision,
rather than general descriptive verbiage. Abo, for the ROD, lengthy discussion of what chemical
constituents were found at the site by media, along with the concentration ranges detected, is not
required. A table outlining these facts much simpler, easier to read and comprehend, and, therefore,
is all that is needed.
3) There is too much discussion of "background* concentrations early on in the draft Record of Decision.
The Record of Decision should, first, concentrate on critical decision pathways, i.e. delineating COCs,
defining acceptable/u nacceptable risk, noting MCL exceedances, and discussing groundwater use. After
all critical decision pathway* have been evaluated, and the need for remediation established, then an
evaluation/comparison of "background" concentrations to COCs should be performed to determine
if remediation can effectively reduce risk at a site.
4) Please incorporate appropriate changes to the draft revised Record of Decision to reflect the changes
made to the RI/BRA and Proposed Plan for Site 16/SSA 16.
5) It would be extremely beneficial to have a figure(s) depicting the sampling locations of identified
COCs by media, and the corresponding detected concentrations. The draft Record of Decision lacks
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JUL-27-1995 10=56 EPft REG 3 HU1D P.03/07
the focus it needs on identifying COCs. Similar figures have been noted in the remedial investigation
reports for the Naval Base-Norfolk. These figures do not necessarily focus on COCs only, but the
contaminant-specific arrangement is similar to what EPA has in mind. Again, the focus of the ROD
should be on COC identification at the site, and this focus should be done quickly and upfront in the
ROD.
6) Discussion of a *FS" in Section 8 should probably be eliminated.
Specific Comments
1) Page 1. Description of Selected Remedy
Please include a statement in the draft revised ROD explaining that the systemic trade exposure level
to Site 16/SSA 16, under the child residential scenario, presents an unacceptable threat to human
health and that institutional controls will be utilized at Site 16/SSA 16 to alert future users of the
residual risks at Site 16/SSA 16, and to insure that future residential use of Site 16/SSA 16 will be
controlled by the Navy.
Also, please include a brief statement in the draft revised ROD describing the institutional controls
to be implemented at Site 16/SSA 16.
2) Page 2. Section 1.2nd paragraph
The sentence '-Mt Site 16/SSA 16, since no anas of concern were identified at the site-.* should be
changed to something similar to '~M Site 16/SSA 16, tince no unacceptable risk to human health or
the environment was present at the site under the current and predicted future land use for the Naval
Weapons Station, Le. industrial..*.
3) Page 3. Section 1. 2nd paragraph
See Specific Comment No. 1
4) Page 10. Section 5
See Specific Comment No. 1
5) Page 11. Types of Contamination
The focus of the ROD should be to present COCs for each media along with the detected
concentration range of each identified COC Thus, the title of this section should be changed from
'Types of Contamination' to "Identified Contaminants of Concern'. Discussion of chemical constituents
not determined to be COCs should not be included under this section, as this information should be
presented earlier in table form, if at alL Also, background references should not be discussed at this
point in the document, but later.
6) Page 16. Section 8
See Specific Comment No. 1
7) Page 19. 2nd paragraph
It is a given that this section will be modified based upon changes already made to the RI/BRA and
Proposed Plan for Site 16/SSA 16. However, this paragraph should be modified to reflect specific
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JUL-27-1995 10=57 EPA REG 3 HUMD P.04/07
comment no. 1, and should emphasize the current and future predicted industrial land use of the
Naval Weapons Station.
8) Section 8
Since there appears to be a unacceptable systemic toxic exposure level present at Site 16/SSA 16,
under the child residential scenario for both surface soil and ground water, Section 8 needs to be
expanded to clearly define what threats to human health each media contribute to the overall threat
There appears to be adequate discussion of the groundwater pathway, but surface soil appears to be
overlooked. Of the total re-calculated HI value of 52 presented by Site 16/SSA 16, the surface soil
HI contributes approximately 38 % (HI value of 2) to the overall HI, and therefore warrants
attention.
This completes EPA's preliminary review comments on the draft Record of Decision for Site 1&5SA
16, located at the WPNSTA. It is anticipated that changes to the text of the draft Record of Decision for Site
16/SSA 16 are needed to reflect the change* made to the RI/BRA and Pnpoted Plait for Site 16/SSA 16,
therefore, the draft version of the Record of Decision has not been circulated throughout the Region for review.
Instead, EPA requests that a revised draft Record of Decision be prepared, addressing the above comments
along with incorporating necessary changes to reflect modifications made to the RI/BRA and Proposed Plan,
and sent to EPA for full review.
If you have any questions, please feel free to call me at (215) 597-1110,
Sincerely,
Robert Thomson, PE
VA/WV Superfund Federal Facilities (3HW71)
cc Steve Mihalko (VDEQ, Richmond)
Jeff Harlow (WPNSTA, Code 09E)
Paul Leonard (USEPA, 3HW71)
Nancy Rios (USEPA, 3HW13)
Bruce Rundell (USEPA, 3HW13)
Bob Davis (USEPA, 3HW13)
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08/09/95 09:43
T flU&-<3e-l99S IS'28 grH« o «-•*, l-AM*!* CODE 18
« 001/002
UNITED STATES BMRONMENTAL PROTECTION AGENCY
REGION B
MlChoBiurBuOdlng
PNhdeljpfifc, Ptfnyfaaria 19107
--.. - .
Robart Thomson, Pi FAX c*is) S8T
Mai Code SHWM
SBM110
Data Auguat «. 1B95
M». Breoda Norton, PB
Atlantic Division, Naval FacStttiet BnjSneerSng Command
Enrfcoianenal Qaafity Division
Code: 1822
Building H 26, Reoa 54
1510 Gilbert Street
Norfolk, Vt 235U-2699
Nav»i Wupow Sutton, Yotkava, Vt.
Ste 16 and Slu SoeadB{ Ana 16
Review of draft final .Rand TvoXentdial Investigation 4 Basda* KskAsteumau
Dear Mi.
U.3. Eavirea&watd PiotMloa Agency CBPA) fcu mimed tb* Kr^ti 4nft fiMlJtoviirf 7W0
the Naval Weapons Statioa-Yodttown (WPNSTA) NPL ftcfllty, along vidl the Navy^ July 24. 1S95 tcspocae
toner to EPA'c June 26 rwipv comments. Based 1900 that review, EPA bas the fbDowinj coameau and
suggestions to offer eft The draft final docoaeot
A Quality Aisvanea and Quitity Connol (QA/QC) Repon is not provided tor wferenc*. QA/QC
data are provided tor Sites 16 and Site Scrteaiax Area lS,bmttappeantnatafonnalr«M«woftn«
data quality was not provided in the dnfl final document. llaNay/i July 24, 1995 rtsponse letter
states that a QA/QC report Sat Site ItySSA 16 wffl U ttibmhttd *^»arateJy ac pan of a QA/QC repon
tbat «01 include Site* 6, 7, U, and Backpeuad at «*& as Ste 10/SSA 16. Tikis it not acceptable to
EPA. If EPA concurrence on a final Record of Dtdston. is cxpeatd for She XeVSSA 16. Oen E
QA/QC Report far Sfee 16/5SA 16 Should be submitted tor EPA review before th* ROD is finalized.
The Navy's July 24> 199S rtsponse letter wus that *u there at no igtaeey table risk* aunciattd wtih
this titt, cfcii will not be eenducted.* 0 not true. Thaw b an unacceptable uadc cqmure level at Site
16/5SA 16, under the enfld reridential scenario fox both mtice soQ aad gpmndinitex. Tbcreftte, tbe
ntional* for act performing a Monte Cario Simulation is &oi coppotted by ibe N«pah^ t^k nngea pmnulgated by m« EPA (a.g.. a. cancer risk of 1R04-.1R06
and a bazard fndec of 1).
PosUt* brand fax transmittal mamo 7671
TT'
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IANIDIV CODE 18 B002/002
conclude EPA'* commons OB the Nwyt drift flail JtaMrf 2Wo Kurudiai Investigate* and
Settling Ktk Amssmera fcr Sit* 16 afid SSA 16, knM.at the WPNSTA. NPL flcflity. If you. hive aay
qocsdeas icpnttnf the above, pfeaie fed frt* to ca& me at (215) 59M1HX
VA/W Saperfkal Prfomt Fadffdev (8HW7I)
ccr Stephcs Mibalktx (VADEQt RichaaotuS)'
Jeff Harlow (WPN5TA. CbdtOSE)
Andy K>1* (BVWST, PhOa.)
Niacy Jitolla (USE? A, SHW13)
Breee Ruadcli (USEPA. 3HW13)
Robcn Davb (USEPA, 3HWU)
TOTflL P.B3
ZOO/200® C OVJ 3HV3 aiflDV G 6t:OT S6/60/80
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