PB98-963919
EPA 541-R98-184
March 1999
EPA Superfund
Record of Decision:
Naval Weapons Station-Yorktown
OUs VI & VII
Yorktown, VA
3/23/1998
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Final
v.3
Record of Decision
Operable Unit Nos. VI and VII
Site 9 - Plant 1 Explosives-Contaminated Wastewater
Discharge Area
and
Site 19 - Conveyor Belt Soil at Building 10
Naval Weapons Station Yorktown
Yorktown, Virginia
March 1998
* PRO^ฐ
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TABLE OF CONTENTS
Page
LIST OF ACRONYMS AND ABBREVIATIONS
v
1.0 DECLARATION OF THE RECORD OF DECISION
1.1 Site Name and Location
1.2 Statement of Basis and Purpose
1.3 Assessment of the Sites
1.4 Description of the Selected Remedy
1.5 Statutory Determination
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-1
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2.0 DECISION SUMMARY 2-1
2.1 Site Name, Location, And Description 2-1
2.1.1 Site 9 - Plant 1 Explosives-Contaminated Wastewater Discharge
Area 2-1
2.1.2 Site 19-Conveyor Belt Soil at Plant 1 2-1
2.2 Site History and Enforcement Activities 2-4
2.2.1 Site History 2-4
2.22 Enforcement Activities 2-5
2.2.3 History of Previous Investigations 2-6
2.3 Highlights of Community Participation 2-7
2.4 Scope and Role of the Remedy 2-8
2.5 Summary of Site Characteristics 2-9
2.6 Summary of Site Risks 2-9
2.6.1 Human Health Risk Assessment 2-11
2.6.2 Ecological Risk Assessment 2-20
2.6.3 Summary of Risk Assessment Results 2-32
2.7 Description of Remedial Alternatives for Site 19 2-33
2.7.1 Alternative 1: No Action 2-33
2.7.2 Alternative 2: No Action with Institutional Controls 2-33
2.7.3 Alternative 3: Capping 2-34
2.7.4 Alternative 4: Excavation/Biological Treatment/Reuse-Recycle... 2-3S
2.7.5 Alternative 5: Excavation/Soil Washing/Incineration 2-36
2.7.6 Alternative 6: Excavation/Off-Site Incineration 2-37
2.8 Summary of the Comparative Analysis of Alternatives 2-37
2.8.1 Threshold Criteria 2-40
2.82 Primary Balancing Criteria 2-41
2.8.3 Modifying Criteria State Acceptance: 2-45
2.9 Selected Remedy 2-46
2.10 Performance Standard 2-46
2.11 Statutory Determination 2-49
2.11.1 Overall Protection of Human Health and the Environment 2-49
2.112 Compliance with ARARs 2-50
2.11.3 Cost Effectiveness 2-54
it
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TABLE OF CONTENTS
(Continued)
Page
2.11.4 Use of Permanent Solutions and Alternative Treatment
Technologies or Resource Recovery Technologies to the
Maximum Extent Practicable 2-54
2.12 Documentation of Significant Changes 2-54
3.0 RESPONSIVENESS SUMMARY 3-1
3.1 Overview 3-1
3.2 Background on Community Involvement 3-2
3.3 Summary of Comments Received During the Public Comment Period 3-2
4.0 REFERENCES 4-1
LIST OF TABLES
2-1 Statistical Summary of Human Health Chemicals of Potential Concern from
Surface Soil Sample Analyses, Site 9 2-13
2-2 Statistical Summary of Human Health Chemicals of Potential Concern
from Shallow Subsurface Soil Sample Analyses, Site 9 2-14
2-3 Statistical Summary of Human Health Chemicals of Potential Concern
from Surface Water Sample Analyses, Site 9 2-15
2-4 Statistical Summary of Human Health Chemicals of Potential Concern
from Sediment Sample Analyses, Site 9 2-16
2-5 Incremental Lifetime Cancer Risk (ILCR) and Hazard Index (HI) for Future Adult
and Child On-Site Residents, RME and Central Tendency Valves, Site 9 2-17
2-6 Potential Human Health Risks Associated with Site 9 by Chemical (RME) 2-19
2-7 Statistical Summary of Human Health Chemicals of Potential Concern
from Surface Soil Sample Analyses, Site 19 2-21
2-8 Statistical Summary of Human Health Chemicals of Potential Concern
from Shallow Subsurface Soil (0-2*) Sample Analyses, Site 19 2-22
2-9 Incremental Lifetime Cancer Risk (ILCR) and Hazard Index (HI) for Future Adult
and Child On-Site Residents, RME and Central Tendency Values, Site 19- 2-23
2-10 Potential Human Health Risks Associated with Site 19 By Chemical (RME) 2-24
2-11 Incremental Lifetime Cancer Risks (ILCRs) and Hazard Index (HI) Values
for Conveyor Belt Surface Soil Samples - Site 19 2-2S
2-12 Statistical Summary of Ecological Chemicals of Potential Concern from
Surface Soil Sample Analyses, Site 9 2-26
2-13 Statistical Summary of Ecological Chemicals of Potential Concern from
Surface Water Sample Analyses, Site 9 2-27
2-14 Statistical Summary of Ecological Chemicals of Potential Concern from
Sediment Sample Analyses, Site 9 2-28
2-15 Statistical Summary of Ecological Chemicals of Potential Concern from
Surface Soil Sample Analyses, Site 19 2-29
2-16 USEPA Evaluation Criteria for Remedial Alternatives - Sites 9 and 19 2-38
in
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LIST OF TABLES
(Continued)
2-17 Summary of Detailed Analysis - Sites 9 and 19 2-39
2-18 Cost Estimate: RAA No. 4 - Excavation/Biological Treatment - Site 19 2-47
LIST OF FIGURES
2-1 Location of Naval Weapons Station Yorktown 2-2
2-2 Locations of Sites 9 and 19 2-3
2-3 Site 19, Conveyor Belt Area 2-10
Appendix A July 21,1997 Public Meeting Transcript
IV
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LIST OF ACRONYMS AND ABBREVIATIONS
AOC
ARAR
bgs
CERCLA
CRP
CT
DoD
DoN
ESQD
FFA
FS
HI
HQ
HMX
HRSD
IAS
ILCR
IDW
IR
LANTD[V
LOAEL
mg/kg
ug/L
NCP
NOAEL
NPDES
NPL
NPW
O&M
OU
PAH
PRAP
Area of Concern
applicable or relevant and appropriate requirement
below ground surface
Comprehensive Environmental Response, Compensation and Liability Act
Community Relations Program
Central Tendency
Department of Defense
Department of the Navy
Explosive Safety Quantity Distance
Federal Facility Agreement
Feasibility Study
hazard index
hazard quotient
Octahydro-1,3,5,7-tetranctro-1,3,5,7-tetrazocine
Hampton Roads Sanitation District
Initial Assessment Study
incremental lifetime cancer risk
Investigation Derived Waste
Installation Restoration
Atlantic Division, Naval Facilities Engineering Command
Lowest Observed Adverse Effect Level
milligrams per kilogram
micrograms per liter
National Oil and Hazardous Substances Pollution Contingency Plan
No Observable Adverse Effect Level
National Pollutant Discharge Elimination System
National Priorities List
net present worth
operation and maintenance
Operable Unh
Polynuclear Aromatic Hydrocarbon
Proposed Remedial Action Plan
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RA
RAA
RAB
RCRA
RDX
RI
RME
RL
ROD
SARA
SMCL
SWMU
TAL
TCL
TBC
TNT
UCL
USEPA
LIST OF ACRONYMS AND ABBREVIATIONS
(Continued)
risk assessment
remedial action alternative
Restoration Advisory Board
Resource Conservation and Recovery Act
Hexahydro-1,3,5-trinitro-1,3,5-triazine
Remedial Investigation
Reasonable Maximum Exposure
Remediation Level
Record of Decision
Superfund Amendments and Reauthorization Act
Secondary Maximum Contaminant Level
Solid Waste Management Unit
Target Analyte List
Target Compound List
to-be-considered criterion
2,4,6-trinitrotoluene
Upper Confidence Limit
United States Environmental Protection Agency
WPNSTA Yorktown Naval Weapons Station Yorktown
VI
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1.0 DECLARATION OF THE RECORD OF DECISION
1.1 Site N>IM and
Naval Weapons Station (WPNSTA) Yorktown, Yorktown, Virginia
Sites 9 and 19; Operable Units (OUs) VI and VQ
1.2 Statement of Baaia and Pa
This Record of Decision (ROD) documents the selected remedial action to reduce the risks posed by
soil, surface water and sediment at Site 9 and soil at Site 19 located at WPNSTA Yorktown,
Yorktown, Virginia. Soil contaminated by 2,4,6-trinhrotoluene (2,4,6-TNT) and RDX (explosives)
at Site 19 is designated as OU VI and soil, surface water, and sediment at Site 9 are designated as OU
VII. The remedial action is chosen in accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 (CERCLA) as amended by the Superfund Amendments and
Reauthorization Act (SARA) of 1986, and, to the extent practicable, with the National Oil and
Hazardous Substances Pollution Contingency Plan (NCP). The information supporting die decisions
on the selected remedy is contained in die administrative record. Section 22.2 lists major documents
contained in the administrative record.
The Commonwealth of Virginia concurs with die selected remedy.
1.3 Assessment of thg Sitea
Actual or direatened releases of hazardous substances from OU VI, if not addressed by implementing
the remedial action selected in this ROD, may present an imminent and substantial endangerment to
human health and the environment No action is proposed for OU VII because risks posed to human
health and the environment fall widiin acceptable or manageable ranges, and remediation will cause
greater harm to the environment than leaving contaminants in place.
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1.4 Description of tfce Selected Remedy
The cleanup of OU VI and the selection of the no-action alternative for OU VII are part of a
comprehensive environmental remediation currently being performed at WPNSTA Yorktown under
the Department of Defense (DoD) Installation Restoration (IR) Program.
The removal and treatment of soil at Site 19 addresses the principal threat to human health and the
environment at OU VI by eliminating source materials (2,4,6-TNT and RDX) and eliminating the
potential release of these contaminants to the environment Major components of the selected remedy
for OUs VI and VII include:
OUVI
Dismantling and disposal of the Site 19 conveyor belt
Excavation of soil beneath the belt to a depth of approximately 4 feet
Excavation of aluminum contaminated soil (above Station-wide background) to
approximately 6 inches around Building 527 and disposal in the bottom of the
conveyor belt excavation area.
Backfilling (with clean soil) and regrading the conveyor belt area and the area around
Building 527.
Biological treatment of excavated explosives-contaminated soil at the WPNSTA
Yorktown btocell and placement of treated soil at Site 22 (Former Burn Pad) now
occupied by the WPNSTA Yorktown biocell.
own
No action at OUVH.
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1.5
Statutory Determination
The selected remedy is protective of human health and the environment, complies with federal and
state requirements that are legally applicable or relevant and appropriate requirements (ARARs) to
the remedial action, and is cost-effective. The remedy uses permanent solutions and alternative
treatment technologies to the maximum extent practicable. The setoctedxemedy meets the statutory
preference for treatment Because the remedies discussed will result in hazardous substances
remaining on-site above conservative risk-based levels, a review will be conducted within five years
after commencement of remedial actions to ensure adequate long-term protection of human health and
the environment is maintained.
2/26/9S
Captain S.A. Denham, Commanding Officer
Naval Weaons Station Yoffctawa, Yorktown, Virginia
Date
Abraham Ferdas, Acting Division Director
Hazardous Waste Management
United States Environmental Protection Agency, Region 10
Date
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2.0 DECISION SUMMARY
2.1 Site Name. Location. And Description
WPNSTA Yorktown is a 10,624 acre installation located on the Virginia Peninsula in York and James
City Counties and the City of Newport News (Figure 2-1). The Station is bounded on the northwest
by the Navai Supply Center Cheatham Annex, the Virginia Emergency Fuel Farm, and the future
community development 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.
2.1.1 Site 9 - Plant 1 Explosives-CoaUminated Wastewater Discharge Area
Site 9 (Figure 2-2) consists primarily of a discharge area that had been used as a drainage way by
Plant 1. Explosives-contaminated wastewater and organic solvents may have been discharged from
Plant 1 into the drainage way. The Site 9 study area is bordered by Bollman Road to the west, an
abandoned railroad track to the north, Plant 1 to the east, and Site 19 to the south.
The Site 9 drainage ditch runs east to west, away from Plant 1, crossing under Bollman Road through
a culvert and ultimately emptying into Lee Pond. Lee Pond drains into the eastern branch of Felgates
Creek, which in turn flows northward to the York River, approximately 1.5 miles from Site 9.
2.1.2 Site 19 - Conveyor Belt Soil at Plant 1
S ite 19 (Figure 2-2) consists of soil surrounding a conveyor belt, which was formerly used to transport
packaged TNT powder from Plant 1 to Building 98. The conveyor belt, which runs northeast to
southwest, is located within an earthen trench. Several buildings and sheds are located within the
Site 19 study i
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1 inch = 8333 ft
LOCATION OF NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VnOJNIA
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LOCATIONS OF
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2.2 Site Hiatory and Enforcement Activities
2.2.1 Site Hiatory
Originally named the U.S. Mine Depot, WPNSTA Yorktown was established in 1918 to support the
laying of mines in the North Sea during World War I. For 20 years after World War I, the depot
received, reclaimed, stored, and issued mines, depth charges, and related materials. During World
War II, the facility was expanded to include three additional 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 depot was redesignated the U.S. Naval
Weapons Station. 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 in support of
national military strategy.
Site 9 reportedly received Plant 1 wastewater discharge from the late 1930s to 197S. Wastewater was
generated as a part of high explosives loading operations which took place at Plant 1 during this time
period. In 1974, a carbon adsorption tower was installed to treat the contaminated wastewater
emanating from Plant 1 prior to discharge to the drainage way. A National Pollutant Discharge
Elimination System (NPDES) permit was granted by the United States Environmental Protection
Agency (USEPA) Region III to allow this discharge. In 1986, treatment tower discharge was diverted
to the sanitary sewer and ultimately to the Hampton Roads Sanitation District (HRSD).
The Site 19 conveyor belt is enclosed on top and along its sides. TNT dust was released to the soil
below and around the conveyor belt during loading activities as high explosives were moved along
the conveyor belt to the kettles at Plant 1. In addition, past operational practices involved the routine
spraying of the conveyor walls and floors with water to control the potential buildup of TNT dust
This water likely dripped onto the ground surface below the conveyor. TNT-contaminated soil was
previously reported in the vicinity of the conveyor belt and an undocumented quantity of soil beneath
and around the belt was voluntarily excavated and removed in 1973-1974 by Station personnel.
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2.2.2 Enforcement Activities
On October 15, 1992, WPNSTA Yorktown was included on the National Priorities List (NPL)
because of the facility's proximity to wetlands and the potential impact on the surrounding
environment A Federal Facility Agreement (FFA) between USEPA Region HI, the Commonwealth
of Virginia, and the Department of the Navy (DoN) was finalized in August of 1994 for WPNSTA
Yorktown. The FFA covers the investigation, development, selection, and implementation of response
actions, satisfying WPNSTA Yorktown's Resource Conservation and Recovery Act (RCRA)
corrective action obligations as well as appropriate provisions of CERCLA for all sites, RCRA Solid
Waste Management Units (SWMUs) and RCRA Areas of Concern (AOCs).
In September 1994, a removal action was conducted at Site 9 to address miscellaneous debris at the
lower end of the drainage way before it crosses Bollman Road. Debris and soil were excavated, clean
fill was added, and the area was graded and vegetated.
No other documented enforcement activities have been conducted at either Sites 9 or 19 under the
FFA.
The following documents provide details of the site investigations and assessments of cleanup actions
for OUs VI and VII.
C.C. Johnson & Associates, Inc. and CH2M Hill. Initial Assessment Study of Naval
Weapons Station. Yorktown. July 1984.
Dames & Moore. Confirmation Study Step LA (Verification V Round One. Naval
Station. Yorktown. Virginia. June 1986.
Dames & Moore. Confinimti,Qfl Study Steo LA (Verification^ Round Two. Naval
WC8IK>flS StttJQP- Yorictown. Virginia. June 1988.
Dames & Moore. Draft Remedial Investigation Interim Renort. Naval Weapons
Station. YorktQwnr Virginia. February 1989.
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Baker Environmental, Inc. and Roy F. Weston, Inc. Final Round One Rem^;,,!
Investigation Report for Sites 1-9. 11. 12. 16-19 and 21 Nfava| Weapon*
Yorictown. Virginia. July 1993.
Baker Environmental, Inc. Final Round Two Remedial Investigation
Sites 9 and 19. Naval Weapons Station Yorictown. Yorktown. Viryinia.
January 1997.
Baker Environmental, Inc. Final Feasibility Study Report for Sites 9 and 19. Naval
Weapons Station Yorictown. Yorictown. Virginia. June 1997.
Baker Environmental, Inc. Final Explosives Conttininfltcd Soil Pilot Study Renort.
Naval Weapons Station Yorktown. Yorktown. Virginia. July 1997.
2.2 J History of Previous Investigations
The purpose of the Initial Assessment Study (IAS) (C.C. Johnson & Associates, Inc. and CH2M Hill,
July 1984) was to identify and assess sites posing a potential threat to human health and/or the
environment due to contamination from past operations. A total of 19 potentially contaminated sites
were identified based on information from historical records, aerial photographs, field inspections, and
personnel interviews. Each site was evaluated for the type of contamination, migration pathways, and
pollutant receptors. The IAS concluded that IS of the 19 sites, including Sites 9 and 19, were of
sufficient threat to human health or the environment to warrant Confirmation Studies.
A Confirmation Study was men conducted for the IS sites identified in the IAS. Two rounds of data
were obtained during the Confirmation Study. The first round of data was collected in the winter
of 1986. This effort was documented in the "Confirmation Study Step LA (VerificationX Round One,"
(Dames A Moore, June 1986). The second round of sampling was conducted during November and
December 1987. The results of the analyses and comparisons with appropriate regulatory standards
were presented in the "Confirmation Study Step LA (VerificationX Round Two," (Dames A Moore,
June 1988).
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The 15 sites, including Sites 9 and 19, were recommended for further study and were evaluated as pan
of the Round One Remedial Investigation (RI) (July 1993). Soil, surface water, sediment and
groundwater were collected and analyzed for Target Compound List (TCL) organics, Target Analyte
List (TAL) inorganics and nitnmine/nitroaromatic compounds (explosives). Data generated during
the Round One RI was compared to standards and/or available criteria and the sites were further
recommended for additional investigation, if necessary. Sites 9 and 19 indicated the presence of
contamination in soil and groundwater and were, therefore, targeted for more comprehensive
investigation and a baseline risk assessment to better evaluate the significance of site related
contamination.
The Round Two RI and report for Sites 9 and 19 were completed in January of 1997. Additional soil
data indicated that contamination was present at both sites. A subsequent soil investigation conducted
as part of a soil pilot scale treatability study indicated higher detected soil concentrations in composite
samples taken at Site 19 than in discrete samples taken during both remedial investigations. As such,
soil samples were obtained from directly under the conveyor belt at Site 19 and from hot spots at both
Sites 9 and 19. These sample data were used as part of the Feasibility Study (FS) Report (June 1997)
to determine tile extent of soil contamination. FS soil data confirmed that the highest levels of
contamination were under the conveyor belt at Site 19. Site 9 exhibited little soil contamination from
explosives.
2J Highlights of Community Participation
The Proposed Remedial Action Plan (PRAP) for Sites 9 and 19 was released to the public in
June 1997 at the four information repositories listed below:
York County Public Library
8500 George Washington Highway
Yorictown, V A 23692
(757)890-3377
Newport News City Public Library
366 Deshazor Drive
Newport News, VA 23506
(757)247-8506
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Gloucester Public Library
P.O. Box 367, Main Street
Gloucester, VA 23601
(804) 887-4720
Naval Weapons Station Yorktown
Environmental Directorate
Building 3 1-B, P.O. Drawer 160
Yorktown, VA 23691-0160
(757) 887-4775 (ext 29) (Contact: Mr. Jeff Harlow)
The notice of availability of this document was published June 29, 1997 in the Daily Press. A public
comment period was held from June 30, 1997 to August 13, 1997. A fact sheet that summarized the
Proposed Plan was distributed to attendees of the Public Meeting held at the York County
Recreational Services Meeting Room, 30 1 Godwin Neck Road, Yorktown, Virginia, on July 21,1 997.
This meeting was held to inform interested members of the community about the preferred remedial
alternative under consideration. Responses to comments received during the public comment period
and a transcript of the Public Meeting are included in the Responsiveness Summary in Section 3.0 of
this document
2.4 Scope and Role of the Remedy
Sites 9 and 19 are part of comprehensive environmental investigations being conducted under the IR
Program at WPNSTA Yorktown. OU VI consists of explosives contaminated soil at Site 19. OU VII
consists of soil, surface water and sediment at Site 9. Although conservative modeling predicts some
potential for ecological risk at Site 9, remediation of the site would generate more harm to the
surrounding ecology by destroying habitat and potentially creating erosion problems in the Site 9
drainage ditch. As such, No Action is recommended for OU VII from an ecological perspective.
Human heahh risks at She 9 fall within the acceptable risk range for current receptors and future
potential receptors, supporting the No Action decision for this OU.
To protect human heahh and the environment, soil beneath the She 19 conveyor belt will be excavated
to a depth of approximately 4 feet The soil will be treated biologically at the Site 22 biocell. A small
potentially ufFrri t*ti
Building 527 will be excavated to a depth of approximately 6 inches if soil-borne aluminum
concentrations exceed the 95th percentile upper confidence limit (UCL) of anthropogenic background
2-8
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(i.e., greater than 14,830 milligrams per kilogram [mg/kg]). All excavated areas will be backfilled
with clean soil and regraded.
2.5 Summary of Site, Characteristics
Results of previous investigations indicate that soil beneath the conveyor belt at Site 19 requires
remedial action (Figure 2-3). The Round Two RI indicates that contamination under the belt could
migrate via runoff or leach through the soil and potentially impact groundwater. Contaminants of
concern at Site 19 include 2,4,6-TNT, RDX, and aluminum. Aluminum is limited to the area around
Building 527 where aluminum oxide powder was added as part of high explosives formulation. The
total volume of soil to be remediated at Site 19 is 1,685 cubic yards as estimated using existing
analytical data. Based on limited sampling, depth of 2,4,6-TNT and RDX contamination is
approximately 4 feet below ground surface (bgs). Soil data also suggests that aluminum
contamination is confined to me top 6 inches of soil around Building 527.
Previous investigations also indicate that inorganics including lead, chromium, copper, arsenic and
iron are present in soil and sediment samples in or near the Site, 9 drainage ditch. The drainage ditch
received discharge from Plant 1 and this discharge is ultimately received by Lee Pond. Concentrations
of inorganics and the presence of organks including polynuclear aromatic hydrocarbons (PAHs) and
explosives indicate residual impacts from past Plant 1 activities. The presence of explosive
compounds in Site 9 drainage ditch surface water appears to be associated with runoff from the Site 19
conveyor belt and as such will be addressed by the Site 19 remedial action. Because inorganic
constituents are similar to Station-wide background concentrations and remediation of Site 9 soil and
sediment would be detrimental to the local ecology (i.e., loss of habitat, erosion), no action is
necessary at this time.
Support for the proposed remedial action at site 19 and No Action at Site 9 is presented in the
Summary of Site Risks section of this ROD.
2.6 Summary of Site Rhka
A baseline risk assessment (RA) was conducted as part of the Sites 9 and 19 Round Two Remedial
Investigation Report (Baker, 1997). Both human health and ecological risk assessments were
conducted. This section presents the results of the baseline RA and those contaminants associated
with unacceptable human health risks and potential adverse ecological effects.
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APmOJUMATE
am
TUDV
02 - MOMIMwe MU1 ซCUMซ M MM KM
FIOURE 2-3
SITE 18
CONVEYOR BELT AREA
YORKTOWM VROMA
NAVAl WEAPONS STATION VOflKTOWN
2 10
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2.6.1 Human Health Risk Assessment
Because of the nature of activities conducted at and around Sites 9 and 19, potential current human
exposure is limited. Both sites lie within the Explosive Safety Quantity Distance (ESQD) arc
(associated with the storage of munitions) and inside of the restricted area of the Station. Current
potential human receptors evaluated in the baseline RA include:
Adult Civilian Workers (Site 9)
Adult On-Site Commercial Workers (Site 19)
Adult civilian workers work infrequently at Site 9 because of ongoing ordnance loading operations
at Building 10. Exposure frequency was assumed to be approximately 14 days per year, based on
conversations with Station personnel. Because operations at Site 19 have ceased, the default exposure
frequency of 250 days per year was used.
Future residential property use was also evaluated at Sites 9 and 19. Both children (ages I to 6 years)
and adults were evaluated. Risk values were summed to account for a potential 30 year exposure.
Groundwater was also evaluated as part of the future residential scenario. However, groundwater
quality in the shallow aquifers (Comwallis Cave and Upper Yorktown) precludes potable use.
Although pump tests were not performed for the Comwallis Cave or Upper Yorktown-Eastover
aquifers in the vicinity of Sites 9 and 19, these aquifers produce low yields (0 to 10 gallons per minute
throughout WPNSTA Yorktown) and contain naturally-occurring concentrations of inorganics
including iron, manganese, and zinc in excess of Secondary Maximum Contaminant Levels (SMCLs).
Based on field observations obtained during well purging and development, neither the Comwallis
Cave nor die Yorktown-Eastover aquifer would sustain a residential household requiring 150 gallons
of water per day in the vicinity of Sites 9 and 19. Groundwater was therefore evaluated as a Class III
aquifer and was evaluated in the baseline RA for non-potable use, considering a beneficial use
scenario such as lawn watering and car washing by future residents. Potential human health risks
associated with groundwater under a beneficial use scenario fall within the generally acceptable target
risk range, but the potential effects on the ecology have not been determined. Groundwater is likely
discharging to Lee Pond and will be evaluated when the investigation of Lee Pond is complete. As
such, groundwater at Sites 9 and 19 is not addressed by this ROD.
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The following subsections present a summary of unacceptable risks (i.e., incremental lifetime cancer
risk [ILCR] values > IxlO"4 and hazard index [HI] values i 1.0) for potential human receptors.
Site 9 Human Health Risks
Only future potential residential exposure to contamination at Site 9 produced unacceptable human
health risks. Tables 2-1 through 2-4 present the human health chemicals of potential concern for
Site 9. ILCR values fall within the generally acceptable target risk range for all evaluated media at
Site 9. Table 2-5 presents the associated human health risk to future potential residents at Site 9. HI
values exceeding 1.0 were observed only for future potential residential exposure to surface soil
(HI = 1.2) and drainage ditch surface water (HI * 1.5). These His were evaluated further to determine
those chemicals responsible for the values. Table 2-6 presents risks and HI values for each medium,
pathway and contaminant The constituent arsenic is responsible for HI I values exceeding
1.0 (HQ = 1.06) cumulatively for both ingestion and dermal contact of soil. Arsenic concentrations
detected in Site 9 surface soil ranged from 1.1 mg/kg (9HA08) to 23.3 mg/kg (9HA04). Shallow
subsurface soil arsenic concentrations were somewhat higher, with concentrations ranging from
0.84 mg/kg (9HA08) to 54.7 mg/kg (9HA04). These concentrations fall within the range of
Station-wide background concentrations (which includes anthropogenic background sample data).
Arsenic was detected in the background sampling effort at a maximum detected concentration of
63.9 mg/kg. As such, arsenic could not be distinguished from naturally-occurring concentrations or
concentrations associated with non-site related human activities. Therefore, remediation of arsenic
in Site 9 soil would not be appropriate.
HI values for surface water were driven primarily by the presence of 2,4,6-TNT (480 micrograms per
liter [ng/L]X which produced hazard quotient (HQ) value of 0.91 and a dermal HQ of 0.05 using the
Reasonable Maximum Exposure (RME). A total HI value of 1.5 was derived for exposure to young
children (ages 1 to 6 yean of age). The contaminants 2,4,6-TNT and aluminum were responsible for
the elevated HI value. However, diese contaminants act on different target organs and should not as
such be evaluated cumulatively. When evaluated individually, HI values are below 1.0, indicating no
adverse health effects will likely occur.
Central Tendency (CT) risk calculations for contaminants in surface water produced His below 1.0
for all contaminants.
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TABLE 2-1
STATISTICAL SUMMARY OF HUMAN HEALTH CHEMICALS OF POTENTIAL CONCERN
FROM SURFACE SOIL SAMPLE ANALYSES
SITES
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
CHEMICAL
FREQUENCY
OF
DETECTION
RANGE OF
DETECTED
CONCENTRATIONS
NORMAL RANGE OF STATION
RANGE OF UPPER 95% BACKGROUND
DETECTION ARITHMETIC CONFIDENCE
LIMITS MEAN INTERVAL
INORGANICS (mg/kg)
ARSENIC
BERYLLIUM
MANGANESE
VANADIUM
10/10
2/10
10/10
10/10
11
0.38
53.0
11.0
- 23.3
- 047
- 204
68.6
NA
0.28
NA
NA
NA
- 0.38
NA
NA
1483
022
12348
3366
19.25
0.29
153.22
45.15
0.46L 63 9
0.23J 0.93J
7.6L - 491
5.2J-64.7
SEMIVOLATILES (ug/kg)
BENZO(A)ANTHRACENE 7/10
BENZO(A)PYRENE 7/10
BENZO(B)FLUORANTHENE 9/10
BENZO(K)FLUORANTHENE 7/10
CHRYSENE 9/10
DIBENZO(A.H)ANTHRACENE 4/10
INDENO(1.2>CO)PYRENE 7/10
NITRAMME8 (ug/kg)
2.4.6-TNT 5/10
87
94
56
77
43
55
74
- 1100
- 1200
- 2200
520
- 1200
- 160
- 550
350
350
350
350
350
350
350
420
- 420
350
- 420
- 350
- 460
420
36770
376.40
544.60
20670
42330
161.60
224.20
567.41
56803
932.24
279.95
668.07
193.96
308.31
210 540
120 120
230.00
348.26
NA
NA
NA
NA
NA
NA
NA
NA
Notra:
1) Inorganic data conaldare both Slation-wida and Anthropogenic Background Samples
NA - Not AppKcabto
UCL - uppar Confldanca Lima
-------
TABLE 2-2
STATISTICAL SUMMARY OF HUMAN HEALTH CHEMICALS OF POTENTIAL CONCERN
FROM SHALLOW SUBSURFACE SOIL SAMPLE ANALYSES
SITE 9
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN. VIRGINIA
CHEMICAL
FREQUENCY
OF
DETECTION
RANGE OF
DETECTED
CONCENTRATIONS
RANGE OF
DETECTION
LIMITS
ARITHMETIC
MEAN
NORMAL
UPPER 95%
CONFIDENCE
INTERVAL
RANGE OF STATION
BACKGROUND
N>
INORGANICS (rag/kg)
ALUMINUM
ANTIMONY
ARSENIC
BERYLLIUM
CADMIUM
CHROMIUM
MANGANESE
VANADIUM
19/19
3/19
19/19
10/19
t(V19
19/19
19/19
19/19
3220
3.5
O.M
0.26
061
58
165
8.5
17.000
5.3
54.7
4.1
4.5
465
1830
219
NA
31
NA
0.28
0.52
NA
NA
NA
NA
7.3
NA
0.61
0.76
NA
NA
NA
8231.56
2.43
1816
0.63
0.94
21.86
189.20
41.43
9510.79
2.91
24.15
1.00
1.34
26,14
261.21
59.26
2690 24100
9.2L-110L
046L-63.9
0.23J-0.93J
1.2J-1.5
35-33.5
7 6L - 491
5.2J 64.7
SEMIVOLATILES (ug/kg)
BENZO(A)ANTHRACENE
BENZO(A)PYRENE
BENZO(B)FLUORANTHENE
BENZO(K)FLUOftANTHENE
CHRYSENE
OIBENZO(A.H)ANTHRACENE
INDENO(1,2>CO)PYRฃNE
NtTRAMMES (ug/kg)
1 2.4-DINITROTOLUENE
2.4.6-TNT
7/19
7/19
9/19
7/19
8/19
4/19
7/19
1/19
6/19
68
72
39
64
46
51
53
47
140
1700
1700
2500
980
1900
270
1000
47
33000
340
340
340
340
340
340
340
340
120
440
440
440
440
440
460
440
740
120
307.53
301.42
375.42
224.68
330.68
18063
249.37
452.63
443.50
595.12
29954
49593
200.42
329.56
20011
224579
22308
5276.40
NA
NA
NA
NA
NA
NA
NA
NA
NA
Notes:
1) Inorganic data considers both Station-wide and Anthropogenic Background Samples
NA - Not Appfcabte
UCL Upper Confidence Urn*
-------
TABLE 2-3
STATISTICAL SUMMARY OF HUMAN HEALTH CHEMICALS OF POTENTIAL CONCERN
FROM SURFACE WATER SAMPLE ANALYSES
SITE 9
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
K>
CHEMICAL
INOROAMCS (ugfl.)
ARSENIC
MANGANESE
FREQUENCY
OF
DETECTION
4/4
4/4
RANGE OF
DETECTED
CONCENTRATIONS
2 5
69 - 231
RANGE OF
DETECTION
LIMITS
NA - MA
NA - NA
ARITHMETIC
MEAN
310
144.93
NORMAL
UPPER 95%
CONFIDENCE
INTERVAL
445
216.22
1
RANGE OF
STATION
BACKGROUND
046L-639
7.6L-491
PESTICIDES (uflVL)
HEPTACHLOR EPOXIDE
NITRAMMES (U0VL)
1.3-OINITROBENZENE
2.4-DINITROTOLUENE
2.6-OINITROTOLUENE
2.4.6-TNT
1.3.5-TRINITROBENZENE
HMX
RDX
1/4
1/4
1/4
2/4
4/4
1/3
1/4
2/4
0.08 - O.OB
0.46 - 0.46
6 - 6
2 - 4
25 - 480
044 - 0.44
14 - 14
6 6.1
0.65 - 005
01 - 016
10 - 10
10 - 10
NA - NA
0.11 - 0.17
9.1 - 150
0.51 0.71
0.04
0.17
525
400
16000
0.19
35.69
3.16
0.07
0.40
584
566
415.36
055
74.25
7.06
NA
NA
NA
NA
NA
NA
NA
NA
Notes:
1) Inorganic data considers both Station-wide and Anthropogenic Background Samples
NA Not Applicable
UCL Upper Confidence Llmi
-------
TABLE 2-4
STATISTICAL SUMMARY OF HUMAN HEALTH CHEMICALS OF POTENTIAL CONCERN
FROM SEDIMENT SAMPLE ANALYSES
SITE ซ
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
CHEMICAL
FREQUENCY
OF
DETECTION
RANGE OF
DETECTED
CONCENTRATIONS
RANGE OF
DETECTION
LIMITS
ARITHMETIC
MEAN
NORMAL
UPPER 96%
CONFIDENCE
INTERVAL
I
RANGE OF
STATION
BACKGROUND
INOROAMC8 (mg/kg)
ARSENIC. TOTAL
BERYLLIUM. TOTAL
CHROMIUM. TOTAL
9*
9/9
9/B
5.7
0.26
8.7
555
0.85
- 47.3
NA - NA
NA NA
NA - NA
19.57
0.46
19.81
31.54
0.58
26.52
0.46L-63.9
9.2L-11.0L
3.5-33.5
SEMIVOLATILC8 (u0/kg)
BENZO(A)ANTHRACENE
BENZO(A)PYRENE
BENZO(B)FLUORANTHENE
BENZOOQFLUORANTHENE
CHRYSENE
DIBENZO(A.H)ANTHRACENE
INDENO<1,2.^CD)PYRENE
NITRAMWES (U0/kg)
2.4-DINITROTOLUENE
2.4,8-TNT
8/9
7/9
7/9
6/9
8/9
5/9
7/9
1/9
6/9
42 - 2400
46 2100
60 - 2600
110 - 970
54 2600
68 - 300
63 1300
3700
120
3700
620
490 - 490
460 - 490
460 - 490
420 490
490 490
420 - 490
420 490
420 - 590
120 - 120
74967
60344
86833
40369
855.44
164.67
46978
62722
206.67
1295.44
100860
1492.59
602.56
1456.89
235.25
738.04
1341.85
317.71
NA
NA
NA
NA
NA
NA
NA
NA
NA
Notes:
1) Inorganic data considers both Station-wide and Anthropogenic Background Samples
NA - Not Applicable
UCL - Upper Confidence Lima
-------
TABLE 2-5
INCREMENTAL LIFETIME CANCER RISK (ILCR) AND HAZARD INDEX (HI)
FOR FUTURE ADULT AND CHILD ON-SITE RESIDENTS
REASONABLE MAXIMUM EXPOSURE AND CENTRAL TENDENCY VALUES
SITE 9
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Pathway
Surface Soil
Ingestion
Dermal Contact
Subtotal
Surface Water")CT
Ingestion
Detmal Contact
Subtotal
Sediment
Ingestion
Dermal Contact
Subtotal
Receptors
Adults
ILCR
1.7x10**
(1.6 xlO**)
5.7 x 10-ฐ*
(2.0x10**)
7.4 x 10-ฐ*
(3.6x10**)
2.1x10-ฐ*
(4.3 x 10*7)
3.4 x 10*7
(9.4 x 10**)
2.4 x 10**
(52 x lO*7)
3.3 x 10**
(7.8 x 10*1)
1.1x10**
(3.0 xlO*7)
1.4x10**
(3.8 x 10*7)
HI
0.1
(0.03)
0.18
(0.02)
028
(0.05)
0.2
(0.07)
0.29
(0.09)
0.5
(0-2)
0.02
(<0.01)
0.03
(<0.01)
0.05
(0.01)
Children ( 1-6 yrs.)
ILCR
4.0 x 10*1
(1.0 xlO*1)
2.5 x 10*1
(2.1x10**)
6.5 x 10*ป
(1.2 x lO*3)
2.4 x 10**
(1.3 x 10**)
I.5xl0*7
(1.0 xlO*7)
2.6x10**
(1.4x10**)
7.8 x lO*1
(4.9 x 10*7)
5.0x10**
(3 J x 10*7)
1.3 x 10**
(8.2 x 10*7)
HI
0.91
(0.23)
0.31
(0.03)
* ' ''ง*ฃ&'-
,, ,f*afcsv~:
0.96
(0.33)
0.51
(0.15)
> s
;^"p^>
&*$*&:
^{"" ,*?' -"> " - -
0.16
(
-------
TABLE 2-5 (continued)
INCREMENTAL LIFETIME CANCER RISK (ILCR) AND HAZARD INDEX (HI)
FOR FUTURE ADULT AND CHILD ON-SITE RESIDENTS
REASONABLE MAXIMUM EXPOSURE AND CENTRAL TENDENCY VALUES
SITE 9
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Notes:
(l> Risk value derived using organic and total inorganic concentrations.
m Surface water/sediment samples obtained from the intermittent stream in the Site 9 ditch.
() * Central tendency value
Shaded areas indicated exceedances of the USEPA's generally acceptable target risk range or a Hazard
Index equal to or greater than 1.0, but are not apportioned by target organ.
2-18
-------
TABLE 2-6
POTENTIAL HUMAN HEALTH RISKS ASSOCIATED
WITH SITE 9 BY CHEMICAL REASONABLE MAXIMUM EXPOSURE
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Medium/Pathway
Surface Soil
Dermal
Contact
Surface Soil
Accidental
Ingestion
Surface Soil
Total
Surface Water
Ingestion
Surface Water
Dermal Contact
Surface Water
Total
Chemical
benzo(a)pyTtne*
dibenzo(aji)anthracene*
arsenic
benzo(a)pyrene
dibenzo(aji)anthracene
arsenic
2,4/2,6-DinitrotoIuene
2,4,6-Trinhrotohiene
arsenic
2,4/2,6-Dinitrotoluene
2,4,6-Trinitrotoluene
arsenic
Future Recepton
HI (Child)
026
0.8
> * * '
4!^ui^
NA
0.91
0.02
NA
O.OS
0.001
0.97
ILCR
(Child)
9.5x10*
2.6x10*
1.0x10-'
4.6x10-'
1.3x10*
3.2X10*
5.6x10-'
5.5xlO-T
1.2x10*
5.6xlO-7
8.9x10*
6.9x10*
2.4x10*
2.5x10*
HI (Adult)
0.15
0.09
0.24
NA
0.2
0.003
NA
0.03
0.001
0.23
ILCR
(Adult)
2.1xlO-s
5.8x10-'
2.3x10''
2.0x10*
5.5x10-'
1.4x10-'
6.6x1.0-'
4.7x10-'
1.0x10*
4.8x10-'
2.0x10"'
1.6x10-'
5.4x10*
2.4x10*
Note:
* - Dermal pathway is not considered quantitatively for these constituents because of the potential for direct
acting effects.
RME - Reasonable Maximum Exposure
HI - Hazard Index
ILCR Incremental Lifetime Cancer Risk
2-19
-------
Site 19 Humqp Health Risks
Tables 2-7 and 2-8 present the human health chemicals of concern at Site 19. Table 2-9 presents the
risks associated with future potential residential contact of contaminated soil. The presence of
aluminum (HQ = 0.9) and arsenic (HQ = 0.5) combine for an HI in excess of 1.0 (Table 2-10).
However, these contaminants have separate target organs for which reference doses were derived. The
skin (keratosis/hyperpigmentation) is the target organ for arsenic and aluminum causes potential
neurological effects. As such, the HQ values cannot be summed and systemic human health effects
associated with these chemicals will likely not occur.
Additional surface soil samples were obtained from under the conveyor belt to determine whether the
soil was affected by former TNT loading operations. EnSysฎ Test Kits were used to establish the
presence of contamination under the belt and in areas where discrepancies between Round One RI
data and Round Two RI data were evident. Table 2-11 presents the potential human health risk
associated with commercial/industrial exposure to affected conveyor belt soil. The ILCR value
(4.8x10'*) and the HI value (92.0) indicate the potential for unacceptable cancer risks and potential
adverse systemic health effects for this scenario. Other explosive compounds were also detected in
laboratory confirmation samples (HMX RDXX but were not evaluated quantitatively because of the
significant potential risks posed by 2,4,6-TNT.
2.6.2 Ecological Risk Assessment
The objective of the ecological risk assessment is to determine whether past operations at Sites 9 and
19 have adversely affected the ecological integrity of terrestrial and aquatic communities. Tables 2-12
through 2-IS present ecological contaminants of concern for both Sites 9 and 19. Results of the
ecological risk assessment are presented by site in the following subsections.
Site 9 Ecological Risk
Potential ecological risks were evaluated in the terrestrial and aquatic environment at Site 9.
Potential terrestrial receptors considered in the ecological risk assessment for She 9 include: soil
invertebrates, plants, robins, red-tailed hawks, short-tailed shrews, and meadow voles. The
2-20
-------
TABLE 2-7
STATISTICAL SUMMARY OF HUMAN HEALTH CHEMICALS OF POTENTIAL CONCERN
FROM SURFACE SOIL SAMPLE ANALYSES
SITE 19
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
CHEMICAL
FREQUENCY
OF
DETECTION
RANGE OF
DETECTED
CONCENTRATIONS
RANGE OF
DETECTION
LIMITS
ARITHMETIC
MEAN
NORMAL
UPPER 96%
CONFIDENCE
INTERVAL
RANGE OF
STATION
BACKGROUND
INORGANICS (mgftfl)
ALUMINUM
ANTIMONY
ARSENIC
BERYLLIUM
M SEMIVOLATUS(ug/k0)
"" BENZO(A)ANTHRACENE
BENZO(A)PYRENE
BENZO(B)FLUORANTHENE
BENZO(K)FLUORANTHENE
CHRYSENE
INDENO(U.3-CD)PYRENE
2.4.8-TNT
AMINO-ONTS
1/8
7*
6/8
2/8
2/8
3/8
2/8
3/8
2/8
8/8
5880 - 90.600
5.6 - 5.6
068 - 14
0.29 0.73
88 130
95 - 140
43 - 230
51 - 100
39 140
62 130
130 - 380
350 - 2100
NA
5.61
2 -
0.31
NA
5.61
2
0.33
28635.00
2.90
6.29
0.37
4910370
5.02
9.71
0.49
2690-24100
9.2L-11.0L
0.46L-63.9
0.23J-0.93J
370 - 450
370 - 450
370 - 450
370 - 450
370 - 450
370 - 450
180.38
182.50
184.13
172.00
16613
177.13
212.04
211.87
224.71
213.77
208.49
213.85
120 - 120
200 - 200
192.50
871.25
268.28
1348.66
NA
NA
NA
NA
NA
NA
NA
NA
Notes:
1) Inorganic data considers both Station-wide and Anthropogenic Background Samples
NA - Not Applicable
UCL - Upper Confidence Limit
-------
TABLE 2-8
STATISTICAL SUMMARY OF HUMAN HEALTH CHEMICALS OF POTENTIAL CONCERN
FROM SHALLOW SUBSURFACE SOIL (0-2*) SAMPLE ANALYSES
SITE 19
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
CHEMICAL
FREQUENCY
OF
DETECTION
RANGE OF
DETECTED
CONCENTRATIONS
RANGE OF
DETECTION
LIMITS
ARITHMETIC
MEAN
NORMAL
UPPER 96%
CONFIDENCE
INTERVAL
RANGE OF
STATION
BACKGROUND
MOROAMCS (mg/kg)
ALUMINUM. TOTAL 18/18 2450 14000 NA - MA 7567.22 8813.26 26990-24100
ARSENIC. TOTAL 18/18 0.8 37.2 NA - NA 10.37 14.63 0.46L-63.9
BERYLLIUM. TOTAL 17/18 0.28 - 1.7 0.35 - 0.35 0.60 0.78 0.23J-0.93J
CHROMIUM. TOTAL 18/18 6.3 -52.4 NA NA 20.41 25.47 35-335
VANADIUM. TOTAL 18/16 6.8-74 NA - NA 31.30 39.94 5.2-64.7
"* NTTRAMINE8 (ug/kg)
j 2.4,6-TNT 6/18 110 - 2100 120 - 120 368.33 631.27 NA
AMINO-ONTS 4/18 310 - 8200 200 - 200 639.44 1420.87 NA
Notes:
1) Inorganic data conaktore both Station-wide and Anthropogenic Background Sample*
NA - Not Applicable
UCL - Uppar Confidence Urn*
-------
TABLE 2-9
INCREMENTAL LIFETIME CANCER RISK (ILCR) AND HAZARD INDEX (HI)
FOR FUTURE ADULT AND CHILD ON-SITE RESIDENTS
REASONABLE MAXIMUM EXPOSURE AND CENTRAL TENDENCY VALUES
SITE 19
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VmGINIA
Pathway
Surface Soil
Ingestion
Dermal Contact
Subtotal
Receptors
Adults
ILCR
8.5 x 10*
(7.5 x Ifr07)
1.9x10*
(7.8 xlO
2.8 x 10*
(1.5x10*)
HI
0.13
(0.03)
0.3
(0.02)
0.43
(0.05)
Children (1 -6 yrs.)
ILCR
2.0 x 10*
(4.7 x 10*)
8.4 x 10*
(8.5 x Ifr")
2.8 x 10*
(5.6x10*)
HI
1.2
(0.24)
0.54
(0.04)
"* s ^ 3 ' W'-f^^-.^1
Notes:
() = Central tendency values
Shaded areas indicated exceeda
to or exceeding 1.0.
of the USEPA's generally acceptable target risk range or Hazard Indices equal
2-23
-------
TABLE 2-10
POTENTIAL HUMAN HEALTH RISKS ASSOCIATED WITH SITE 19
BY CHEMICAL REASONABLE MAXIMUM EXPOSURE
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Medium/Pathway
Surface Soil
Dermal
Contact
Surface Soil
Accidental
(ngestion
Surface Soil
Total
Chemical
benzo(a)pyrene*
aluminum
arsenic
benzo(a)pyrene*
aluminum
arsenic
Future Potential Receptors
HI (Child)
0.6
0.4
0.3
0.1
, M'\-
%< ' s>*
ILCR
(Child)
l.lxlfr*
1.6x10-'
2.2x10*
5.1x10*
7.3x10*
HI (Adult)
0.07
0.04
0.2
0.07
0.4
ILCR
(Adult)
4.8xlO'T
6.8x10*
5.1x10*
Tป
1.1x10-'
2.5x1 0'ป
Note:
* - Dermal pathway is not considered quantitatively for these constituents because of the potential for direct
acting effects.
Shaded areas indicate exceedences of the USEPAs generally acceptable target risk range or Hazard Indices equal to
or exceeding 1.0.
ILCR - Incremental Lifetime Cancer Risk
HI - Hazard Index
2-24
-------
TABLE 2-11
INCREMENTAL LIFETIME CANCER RISKS (ILCRs) AND HAZARD INDEX (HI)
VALUES FOR CONVEYOR BELT SURFACE SOIL SAMPLES - SITE 19
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
Medium/Pathway
Surface Soil
Accidental
Ingestion
Surface Soil
Dermal
Contact
Surface Soil
Total
Chemical
2,4,6-Trinitrotoluene
2,4,6-Trinitrotoluene
Commercial Worker
HI
14.0
78.0
^ .
s -. ' ' ' ^%S'
ILCR
7.5x10-'
4.5X10-1
4.8X10"
2-25
-------
TABLE 2-12
STATISTICAL SUMMARY OF ECOLOGICAL CHEMICALS OF POTENTIAL CONCERN
FROM SURFACE SOIL SAMPLE ANALYSES
SITE 9
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
CHEMICAL
LinpnAUtta !__._>
WM1UATCHซ9 W^VI
ALUMINUM
BERYLLIUM
CHROMIUM
COPPER
IRON
LEAD
NICKEL
POTASSIUM
SELENIUM
VANADIUM
N> ZINC
N>
9k
8EMIVOtATILE8(ug/kg)
ACENAPHTHENE
ANTHRACENE
BENZO(A)ANTHRACENE
BENZO(A)PYRENE
BENZO(B)FLUORANTHENE
BENZO(O.H.I)PERYLENE
BENZO(K)FLUORANTHENE
BUTYLBENZYLPHTHALATE
CARBAZOLE
CHRYSENE
DIBENZO(A.H)ANTHRACENE
DIBENZOFURAN
FLUORANTHENE
FLUORENE
INOENO(1.2>CD)PYRENE
PHENANTHRENE
PYRENE
FREQUENCY
OF
DETECTION
10/10
2/10
10/10
10/10
10/10
10/10
10/10
10/10
3/10
10/10
10/10
2/10
4/10
7/10
7/10
9/10
7/10
7/10
4/10
4/10
9/10
4/10
2/10
9/10
2/10
7/10
6/10
10/10
RANGE OF
DETECTED
CONCENTRATIONS
3160
0.38
6.7
2.4
5060
9.7
2.6
149
0.4
11.9
10.6
69
58
87
94
56
74
77
55
47
43
55
49
65
75
74
76
35
7750
- 0.47
- 29.8
- 26.1
- 20200
68.4
- 11
- 598
- 0.47
68.6
- 133
120
310
1100
1200
2200
- 770
'S20
310
250
1200
160
77
- 2200
120
- 550
1600
- 2000
RANGE OF
DETECTION
LIMITS
NA
0.28
NA
NA
NA
NA
NA
NA
0.31
NA
NA
350
350
350
350
350
350
350
390
350
350
350
350
350
350
350
350
NA
- NA
- 0.38
NA
NA
NA
- NA
NA
- NA
- 0.47
NA
NA
460
460
420
. 420
350
420
420
470
- 460
350
- 460
- 460
- 350
460
- 420
420
NA
NORMAL
UPPER 95%
ARITHMETIC CONFIDENCE
MEAN INTERVAL
5636.00
0.22
16.40
11.54
13243.00
31.03
5.24
384.60
0.26
33.66
61.39
180.40
188.30
367.70
376.40
544.60
271.80
206.70
164.30
170.10
423.30
161.60
174.10
620.00
181.00
224.20
444.20
656.10
6475.78
0.29
20.97
16.48
16257.33
43.82
6.67
459.53
0.33
45.15
89.38
209.48
228.86
567.41
568.03
932.24
398.90
279.95
230:02
207.51
668.07
193.96
209.80
1018.15
209.23
308.31
739.66
1077.38
RANGE
OF
STATION
BACKGROUND
2690 24100
0.23J - 0.93J
3.50 33.50
1.2J 24.4
2070 - 46400
6.40 43.1
4.2J - 12.5
396J - 1640J
0.21 L - 0.61 L
5.2J - 64.7
3.2KJ 48.4
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NTTRAMINE8 (1*9*9)
AMINO-ONTS
3/10
210 1500
200 - 200
Note*:
1) Inorganic data coraktora Ml) Station-wide and Anthropogenic Background Samples
NA-NotAoatcabto
UCL-Ur onMmcaLkT*
' * t
264.00
517.40
NA
-------
TABLE 2-13
STATISTICAL SUMMARY OF ECOLOGICAL CHEMICALS OF POTENTIAL CONCERN
FROM SURFACE WATER SAMPLE ANALYSES
SITE 9
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
CHEMICAL
FREQUENCY RANGE OF RANGE OF
OF DETECTED DETECTION ARITHMETIC
DETECTION CONCENTRATIONS LIMITS MEAN
NORMAL
UPPER
05%
CONFIDENCE
INTERVAL
RANGE OF
STATION
BACKGROUND
K>
INORGANICS (mo/kg)
ALUMINUM
CYANIDE
IRON
LEAD
PESTICIDES fug/kg)
HEPTACHLOR EPOXIDE
NTTRAMMES (ug/hg)
AMINO-ONTS
4/4
1/4
4/4
1/4
1/4
4/4
IS - 200
28 28
589 - 2960
3.6K 3.6K
0.08 - 0.08
97 1000
NA - NA
10 10
NA NA
1.4L - 1.4L
0.05 - O.OS
NA NA
79.90
10.68
1218.75
1.43
0.04
431.75
181.29
24.03
2585.15
3.13
0.07
933.79
94.4J-1050
NO
630-2500J
16J-15.9
NA
NA
NC*M:
1) Inorganic data a
NA-NotAppHnbto
UCL - Uppw Confidence Untt
Mere both Station-wide and Anthropogenic Background Samples
-------
TABLE 2-14
STATISTICAL SUMMARY OF ECOLOGICAL CHEMICALS OF POTENTIAL CONCERN
FROM SEDIMENT SAMPLE ANALYSES
SITE ซ
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
K)
K>
FREQUENCY RANGE OF
OF DETECTED
CHEMICAL DETECTION ONCENTRATIONS
MOROAMCS fcna/ka)
LHIWI uwuv V'V^W
ALUMINUM
ARSENIC
BERYLLIUM
COBALT
IRON
LEAD
VANADIUM
SEMIVOCATtLES (tig/kg)
ACENAPHTHENE
ACENAPHTHYLENE
ANTHRACENE
BENZO(A)ANTHRACENE
BENZO(A)PYRENE
BENZO(0>H.I)PERYLENE
BUTYLBENZYLPHTHALATE
CARBAZOLE
CHRYSENE
DIBENZO(A.H)ANTHRACENE
FLUORANTHENE
FLUORENE
INDENO(U>CD)PYRENE
PHENANTHRENE
PYRENE
(TRAMMES (ug/kg)
AMINO-ONTS
2.4-DINITROTOLUENE
2.4.6-TNT
9/9
9/9
9/9
M
9/9
9/9
9/9
2/9
219
619
a/9
7/9
719
M9
619
6/9
619
919
419
719
8/9
919
619
1/9
619
1690-
6.7-
0.26-
18-
11100-
7.9-
13.1 -
130-
77-
54-
42-
48-
66-
660-
72-
54-
68-
73-
52-
63-
57-
67-
220-
3700-
120-
6320
66.6
0.65
5.2
54400
100
43.4
220
150
750
2400
2100
1000
660
250
2600
300
4600
420
1300
3200
3300
2300
3700
620
RANGE OF
DETECTION
LIMITS
NA
NA
NA
NA
NA
NA
NA
420
420
420
490
460
420
420
420
400
420
NA
420
420
490
NA
200
420
120
-NA
-NA
-NA
NA
NA
-NA
-NA
-550
550
-490
490
-490
490
-590
-490
490
490
-NA
500
490
490
NA
200
-590
120
ARITHMETIC
MEAN
3861.11
19.57
0.46
3.16
23333.33
29.18
27.67
222.22
208.56
274.33
749.67
603.44
376.78
282.78
185.22
655.44
164.67
1415.76
205.22
469.78
972.44
1097.00
546.67
627.22
206.67
NORMAL
UPPER 95%
CONFIDENCE
INTERVAL
4810.47
31.54
0.58
3.96
31121.00
48.95
33.28
247.03
245.83
409.87
1296.44
1008.60
579.20
371.95
224.64
1456.89
235.25
2473.42
272.92
738.04
1680.95
1855.96
997.78
1341.85
317.71
RANGE OF
STATION
BACKGROUND
482K -
0.27L -
0.28J
1.1J -
329.00
1.8L
1.9J -
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
17700J
544.
0.99J
7.9J
27700J
381 L
38.90
Notts:
1) Inorgu*: data conaktore both Slatton-wid* and Anthropogenic Background Sampla*
NA - Not AppUcatta
UCL-UpConfldancaUn*
-------
TABLE 2-15
STATISTICAL SUMMARY OF ECOLOGICAL CHEMICALS OF POTENTIAL CONCERN
FROM SURFACE SOIL SAMPLE ANALYSES
SITE 19
NAVAL WEAPONS STATION YORKTOWN
YORKTOWN, VIRGINIA
CHEMICAL
FREQUENCY
OF
DETECTION
RANGE OF
OETECETO
ONCENTRAT1ONS
RANGE OF
DETECTION
LIMITS
ARITHMETIC
MEAN
NORMAL
UPPER 96%
CONFIDENCE
INTERVAL
RANGE OF
STATION
BACKGROUND
(mg/kfl)
ALUMINUM 8/8 5880 90600 NA - NA
BERYLLIUM 6/8 0.29 0.73 0.31 0.33
CHROMIUM 8/8 13-31 NA - NA
COPPER 8/8 7.80-42 NA - NA
IRON 8/8 12300 48700 NA - NA
LEAD 8* 48-392 NA - NA
MERCURY 1/8 O.IK - OIK 0.09 - 0.14
VANADIUM 8/8 22.7J - S3 NA - NA
NICKEL 8/8 2.6-7.4 NA - NA
ZINC 8/8 34-365 NA NA
SCMIVOLATILC* (ug/kg)
BENZO(A)ANTHRACENE 2/8 88-130 370-450
BENZO(A)PYRENE 2/8 95-140 370-450
BENZO(B)FLUORANTHENE 3/8 43-230 370-450
CHRYSENE 3/8 39-140 370-450
FLUORANTHENE 5* 46-370 370-450
INOENO(1,2.3-CD)PYRENE 2/8 62-130 370-450
PHENANTHRENE 2/8 75-210 370 - 450
PYRENE ซ8 44 0 210 370-450
MTRAMINE8 (ug/kg)
2.4.6-TNT 6/8 130 380 120-120
28835.00
0.37
23.30
19.38
25575.00
142.80
0.10
36.01
5.18
161.38
180.38
182.50
184.13
166.13
165.63
177.13
188.75
163.88
192.50
49103.70
0.49
2870
27.40
34040.44
218.93
0.07
43.36
6.34
246.02
212.04
211.87
224.71
208.49
240.13
213.85
220.77
209.63
268.28
2690
0.23J
3.5
1.2J
2070
6.4
0.06J
6.2J
4.2J
3.2KJ
24100
0.93J
33.5
24.4
46400
43.1
0.05J
64.7
12.5
48.4
NA
NA
NA
NA
NA
NA
NA
NA
NA
Noter
1) Inorganic data consktera both SUUon-vmto and AnthropagtnJc Background Samples
NA-NoปAppปcaWซ
UCL - Uppw ConfldMK* UmH
-------
terrestrial receptors were selected to represent various trophic levels. Plants and soil invertebrates
were evaluated by a comparison to toxicity values for flora and fauna. Robins, hawks, voles, and
shrews were evaluated through conservative modeling of potential contaminant uptake. Contaminant
uptake was then compared to literature No Observable Adverse Effect Levels (NOAELs) or Lowest
Observable Adverse Effect Levels (LOAELs).
Terrestrial models indicate that aluminum, chromium, iron, lead, and vanadium concentrations in
Site 9 soil could produce unacceptable ecological effects. However, aluminum, chromium, and iron
concentrations fall within Station-wide background concentrations, and it is not considered appropriate
to attempt to cleanup to below background concentrations at Site 9. Concentrations of lead exceed
background concentrations at only three often sample locations. Vanadium exceeds background
concentrations at only one often locations. No apparent source of inorganic constituents has been
identified at Site 9.
Potential aquatic receptors considered in the Site 9 ecological risk assessment include: fish (including
the yellow bullhead catfish), sediment benthic macroinvertebrates, bullfrogs, and great blue herons.
The aquatic receptors are not present in the drainage ditch proper, but were selected to represent
various trophic levels. Sediment benthic macroinvertebrates and fish were evaluated by a comparison
to available benchmarks. Yellow bullhead catfish, bullfrogs and great blue herons were evaluated
using conservative uptake modeling.
Surface water samples collected from the Site 9 drainage ditch contained heptachlor epoxide,
nitramines, aluminum, cyanide, and iron exceeding corresponding benchmark values used to select
ecological contaminants of concern. These contaminants did not produce significant risks
(i.e., ecological HQ values greater than 1.0) to aquatic receptors evaluated using conservative uptake
modeling. Aluminum concentrations fall within freshwater background concentrations. Heptachlor
epoxide was detected in only one of four surface water samples and, from an historical perspective,
its use at Site 9 could not be documented. Iron concentrations are similar to Station background
values and as such, remediation of these constituents is not appropriate at Site 9.
Sediment samples collected from the She 9 drainage ditch contained concentrations of PAHs,
nitramines, aluminum, arsenic, beryllium, cobalt, iron, lead, and vanadium. PAHs did not produce
significant risk to aquatic receptors. Aluminum, beryllium, cobalt, and lead were detected below
2-30
-------
background concentrations for freshwater sediment Vanadium was detected in one 0 to 4 inch
sediment sample (SD09) at 43.4 mg/kg. This concentration is similar to the maximum detected
background vanadium concentration in freshwater sediments of 38.9 mg/kg. AH other vanadium
concentrations in Site 9 sediment samples fell within die Station-wide background range. Maximum
detected concentrations of nitramines and iron were detected in a single deep sample (4 to 8 inches
bgs) obtained from the middle of me drainage ditch where the potential for contact by ecological
receptors is limited Therefore, die need to conduct remediation activities in the ditch is unnecessary.
Sediment concentrations of iron produced risks to die great blue heron using conservative uptake
modeling. An HQ of 45.7 was derived for iron (in die least conservative model). Iron, however, was
detected in deeper sediments (4 to 8 inch depdi) to which the heron is unlikely to be exposed. Lead
produced HQ values in excess of 1.0, but sediment concentrations fall within background. As such,
lead concentrations may not be discernable from background and remediation would not be
appropriate.
Arsenic concentrations in Site 9 sediments exceed background freshwater stream sediment
concentrations. Although HQ values for arsenic exceed 1.0 when using the Effects Range-Low
(ER-L) value, they do not produce unacceptable HQ values when using the Effects Range-Median
(ER-M) value for arsenic. Because arsenic does not produce unacceptable HQ values using die ER-M,
remediation of ditch sediments is not necessary. Remediation of ditch sediments would also cause
greater harm to the local ecology than leaving contaminants such as arsenic, iron, vanadium, and lead
in place.
No action is necessary to protect human health at Site 9.
Site 19 Ecological Risk
Potential ecological risks were evaluated in die terrestrial environment at She 19. There are no aquatic
habitats associated with this site.
Potential terrestrial receptors considered in the ecological risk assessment for Site 19 include: soil
invertebrates, plants, robins, red-tailed hawks, short-tailed shrews, and meadow voles. The terrestrial
receptors were selected to represent various trophic levels. Plants and invertebrates were evaluated
2-31
-------
by a comparison to literature toxicity values for flora and fauna. Soil concentrations of 2,4,6-TNT,
aluminum, chromium, copper, iron, lead, mercury, vanadium, and zinc may be adversely impacting
soil flora and fauna. Terrestrial uptake modeling results indicate that only 2,4,6-TNT, aluminum,
chromium, lead, and iron produce HQ values exceeding 1.0.
Remediation of the inorganic constituents mercury, vanadium, and zinc is not necessary because they
did not produce ecological HQs in excess of 1.0.
2.6 J Summary of Risk Assessment Results
Only future potential residential exposure to soil produced unacceptable human health HI values at
Site 9. Arsenic was responsible for the unacceptable HI values, but was detected at concentrations
that could not be distinguished from Station-wide background.
Inorganics detected in Site 9 sediment samples produced potentially unacceptable risks to aquatic
receptors. Arsenic was detected above background freshwater sediment concentrations, but did not
exceed the ER-M value. Lead was detected below background freshwater sediment concentrations
and below its ER-M value.
Because vanadium was detected in only one shallow (0-4 inch) sediment sample at a concentration
similar to background and iron was detected in a deep (4-8 inch) sediment sample (limiting the
potential for exposure to aquatic receptors), no action is necessary. Remediation of She 9 sediments,
because of arsenic, iron, lead, and vanadium, would be more harmful to the ecology than leaving these
inorganic contaminants in place.
At Site 19, the compound 2,4,6-TNT produced ILCR values in excess of the generally acceptable
target risk range and HI values above 1.0 for current and future potential human receptors. The
compound RDX was also detected at concentrations that could pose unacceptable human health risks,
but was detected at much lower concentrations than 2,4,6-TNT. 2,4,6-TNT, aluminum, iron, and lead
produced unacceptable HQ values above 1.0 for all potential terrestrial receptors. Soil concentrations
of RDX and HMX did not produce unacceptable risks to ecological receptors. Soil under the
conveyor belt must be remediated to protect current and future potential human receptors and
terrestrial environmental receptors. Remediation levels (RLs) of 15 mg/kg and 5 mg/kg were derived
2-32
-------
using exposure scenarios and potential current receptors described in the baseline RA for 2,4,6-TNT
and RDX, respectively. These RLs are protective of both human health and the environment.
2.7 Description of Remedial Alternatives for Site 19
The DoN considered a range of potential alternatives for the remediation of explosives contaminated
soil at Site 19. Each of the "treatment" alternatives (Alternatives 3 through 6) requires that the
conveyor belt at Site 19 be dismantled and disposed of properly. The following alternatives were
evaluated:
Alternative 1 - No Action ~
Alternative 2 No Action with Institutional Controls
Alternative 3 Capping
Alternative 4 - Excavation/Biological Treatment/Reuse-Recycle
Alternatives Excavation/Soil Washing/Incineration
Alternative 6 - Excavation/OfT-Site Incineration
2.7.1 Alternative 1: No Action
This alternative involves no remedial action to contain, remove or treat contaminants in Site 19 soil.
It is not protective of human health or the environment, nor does it comply with ARARs. It was,
however, evaluated to provide a baseline for comparison to other remedial alternatives.
Estimated Capital Cost $0
Estimated Operation and Maintenance (O&M) Costs: $0
Estimated Present Worth Cost: $0
Estimated Time to Implement: Immediate
2.7.2 Alternative 2: No Action with Institutional Controls
This alternative also involves no action to contain, remove or treat She 19 soil contaminants, but does
provide for some protection of human health by restricting property use (i.e., no future residential
development of Site 19 and restrictions concerning groundwater usage in the Station Master Plan).
2-33
-------
This alternative does not protect the environment and does not comply with ARARs as would
"treatment" remedial alternatives.
Estimated Capital Cost: $9,000
Estimated O&M Costs: $ 18,000
Estimated Present Worth Cost: $280,000
Estimate to Implement: Installation of a chain link fence would be completed
within 4 to 6 months (pending receipt of funding), property
use restrictions could be added to the Station Master Plan
during the same time period.
2.7 J Alternative 3: Capping
This alternative calls for contaminated Site 19 soil to be left in place and covered. The cover will
consist ofa 12 inch clay layer or a clay equivalent liner and 6 inches of top soil over the explosives
contaminated soil. It will be designed, constructed and maintained in accordance with appropriate
USEPA and Commonwealth of Virginia criteria and guidance. The areas to be covered will be
delineated with additional sampling. The cover will then be revegetated to prevent the erosion of top
soil. Although no chemical specific ARARs exist, action and location specific ARARs including the
protection of wetlands and erosion and sediment control regulations would be met Because affected
soil at Site 19 is not a listed waste, and affected soil is not hazardous by characteristics (ignitability,
reactivity, corrosivity, toxkity), RCRA Subtitle C (40 CFR Part 261) and Virginia Hazardous Waste
Management Regulations (VR672-10-1/9VAC20-60-10 & sfiQ.) will not apply under this capping
alternative. Land use restrictions (i.e., no future residential development, excavation activities, etc.
within the confines of the cap) will also be implemented.
Estimated Capital Cost $453,000
Estimated O&M Costs: $16,000
Estimated Present Worth Cost: $620,000
Estimated Time to Implement: Dismantling of the conveyor belt, clearing and
grubbing activities can begin in 6 months pending
receipt of funding and approval of the Remedial
Action Work Plan. Land use restrictions will be
added to die Station Master Plan during this time
2-34
-------
period. The cap will be completed within
6 months of the completion of clearing and
grubbing activities.
2.7.4 Alternative 4: Excavation/Biological Treatment/Rense-Recycle
Alternative 4 involves the dismantling and disposal of the conveyor belt, removing soil containing
concentrations of explosives in soil exceeding RL values (to a depth of approximately 4 feet bgs)
beneath the belt, and transporting soil to the biocell at Site 22. Soil will be treated using a carbon
source and microbes to degrade explosive contaminants. Soil will be treated to RLs protective of
human health and the environment, removed from the cell, and applied to the ground around the
biocell.
Hotspot locations of aluminum in soil around Building 527 that could cause potential ecological risks
to terrestrial receptors will also be addressed under this alternative. Details concerning aluminum
contaminated soil disposal will be discussed in the Remedial Action Work Plan which will be
developed prior to remediation activities at Site 19.
The Site 19 area will be backfilled using clean fill and regraded. Institutional controls to prevent
residential property use and groundwater use restrictions will also be implemented. Although no
chemical ARARs exist for soil, action and location-specific ARARs including: RCRA Subtitle C -
surface impoundments (Subpart K), closure and post-closure care of the Site 22 biocell (Subpart G);
protection of wetlands and erosion and sediment control (VR 450-01-0051/4 VAC 20-390-10 ej Sfig.)
will be met Treated soil (i.e., soil below USEPA approved RLs) will be disposed in the area around
the biocell and the excavated areas at She 19 will be backfilled with clean soil and returned to grade.
Estimated Capital Cost: $883,000
Estimated O&M Costs: $0
Estimated Present Worth Cost: $883,000
Estimated Time to Implement: Dismantling of the conveyor belt and excavation
activities can begin in the spring of FY 1998
(approximately 7 months) pending receipt of
funding and approval of the Remedial Action
Work Plan. Warm weather is necessary for
2-35
-------
biological treatment processes. Land use
restrictions prohibiting future residential land use
can be added to the Station Master Plan during the
7 month time period. The total timefhune for
implementation and completion of this remedy is
approximately 6 months.
2.7.5 Alternative 5: Excavation/Soil Washing/Incineration
This alternative is similar to Alternative 4 in that soil will be excavated from the conveyor belt area
to a depth of approximately 4 feet bgs. Rather than soil treatment at the on-site biocell, an on-site soil
washing treatment system would be established at Site 19. The contaminated soil would be washed,
certified to be below RL values, and used as backfill at the she. Contaminated wash residuals will be
transported off site to a permitted incineration facility. Although no ARARs exist for soil, this
alternative will meet action and location specific ARARs including: RCRA-Subtitle C (40 CFR Part
264) Subpart E (manifest system, record keeping and reporting) for off-site transport of residuals,
Subpart I (Use and management of Containers; Subpart K (surface impoundments), protection of
wetlands and erosion and sediment control (VR 450-01-0051/4 VAC 20-390-10 ej SSA-Y, and
Department of Transportation regulations concerning off-she transport of residuals.
Estimated Capital Cost $ 1,418,000
Estimated O&M Costs: $0
Estimated Present Worth Cost: $1,418,000
Estimated Time to Implement Dismantling of the conveyor belt and excavation
activities can begin in 6 months pending the
receipt of funding, approval of the Remedial
Action Work Plan and availability of a permitted
incinerator facility to accept residuals. Property
use restrictions prohibiting residential future
property use will be added to the Station Master
Plan during this time period. This alternative will
be completed within 1 year pending the
identification of a permitted incineration facility
willing to accept residuals.
2-36
-------
2.7.6 Alternative 6: Excavation/Off-Site Incineration
This alternative is similar to Alternative 5 in that Site 19 soil will be excavated, but no on-site washing
will occur. Site 19 soil will be transported to an off-site incineration facility permitted to treat
explosives-contaminated waste. Although no ARARs exist for soil, this alternative will meet action
and location specific ARARs including: RCRA-Subtitle C (Subparts E, I, and K); Department of
Transportation regulations concerning off-she transport of soils (49 CFR Parts 107 and 171.1 -500);
wetlands; and erosion and sediment control (VR 450-01-0051/4 VAC 20-390-10 ฃj seq.l.
Estimated Capital Cost $3,147,000
Estimated OAM Costs: $0
Estimated Present Worth Cost: $3,147,000
Estimated Time to Implement Dismantling of the conveyor belt and excavation
activities can begin in 6 months pending the
receipt of funding, approval of the Remedial
Action Work Plan and availability of a permitted
incinerator facility to accept soil. Property use
restrictions prohibiting future residential property
use will be added to the Station Master Plan during
this time period. This alternative will be
completed within 1 year pending the identification
of a permitted incineration facility willing to accept
soil.
2.8 SuiHimrY of fh* Comparative Anarvaia of Alternative*
As required by CERCLA, the six remedial alternatives were evaluated using the nine criteria specified
by USEPA (Table 2-16). This section and Table 2-17 summarize the detailed analysis of each
alternative.
2-37
-------
TABLE 2-16
USEPA EVALUATION CRITERIA FOR REMEDIAL ALTERNATIVES
SITES 9 AND 19
WPNSTA YORKTOWN, YORKTOWN, VIRGINIA
1. Overall protection of bunan health and the environment
Addresses wfaetber a cleanup method adequately protects human health and the environment
and describes how risks presented by each pathway are eliminated, reduced, or controlled
through treatment, engineering controls, or institutional controls.
Compliance with ARARs
Addresses whether a cleanup method meets all ARARs (federal and state environmental
requirements) and provides grounds for invoking a waiver.
3. Long-term effectiveness and permanence
Refers to the ability of the cleanup method to reliably protect human health and the environment
over time, after the action is completed.
Reduction of toikity, mobility, or volume through treatment
Addresses the effectiveness of a cleanup method in reducing the toxiciry, mobility, or volume of
hazardous substances through treatment
Short-term effectiveness
Addresses the period of time needed to complete the cleanup, and any adverse impacts on
human health and the environment that may occur during construction and operation.
Impiementability
Refers to the technical and administrative feasibility of a cleanup method, including the
availability of required materials and services.
7. Cost
Includes the estimated capital and OAM costs of each cleanup method
8. State acceptance
Indicates whether the Commonwealth of Virginia agrees with the preferred cleanup method.
9. Community acceptance
Indicates whether public concerns are addressed by the cleanup method and whether die
community has a preference. (Public comment is an important part of me final decision.)
2-38
-------
TAULC 2-
SUMMARY OF DETAILED ANALYSIS
SITES* AND 19
WI'NSTA YORKTOWN. VORKTOWN. VIRGINIA
Evaluation
Ovcilll frOMCUVCMtl
Compliance matt ARARa
Unt-TcnEOMivMM
Reduction of To***?.
Mobility, or VotaM
dmvfk Treatment
Shon-Tcrm EtfcaivaMM
Cons(NPW)
RAA 1 No Action
NoratuOKMinruklolujman
t*m*t conditions aim* lot
> Will MM MCI AJIAJU
(miaow
WiilMMKaซปndปCซ
Rot 10 community nM increased.
No itfwAcanl risk w workers.
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2.8.1 Threshold Criteria
Overall Protection of Human Health and the Environment:
Evaluation of the overall protectiveness of alternatives focused on whether a specific alternative would
achieve adequate protection of human health and the environment and how risks posed by each
pathway would be eliminated, reduced, or controlled through treatment, engineering, or institutional
controls. The overall assessment of the level of protection included the evaluations conducted under
other criteria, especially long-term effectiveness and permanence, short-term effectiveness, and
compliance with ARARs.
Alternatives I and 2 are not protective of human health or the environment because waste is left in
place and the potential for exposure is limited, but not eliminated by institutional controls.
Alternatives 3, 4, S and 6 are protective of human health and the environment because waste is
removed (Alternatives 4,5, and 6) or covered (Alternative 3).
Compliance with ARARs:
This evaluation involved determining whether each alternative would meet all of the pertinent Federal
and state ARARs (as identified in Section 2.11.2 of this report).
Each alternative was evaluated for compliance with applicable or relevant and appropriate Federal and
state requirements. The evaluation summarized which requirements are applicable or relevant and
appropriate to each alternative. The following items were considered for each alternative:
Compliance with chemical-specific ARARs (e.g., ambient water quality criteria).
This factor addresses whether the ARARs can be met, and, if not, whether a waiver
may be appropriate.
Compliance with location-specific ARARs (e.g^ preservation of historic sites,
regulations relative to activities near wetlands or floodplains, etc.). As with other
ARAR-rdated factors, these involve consideration of whether the ARARs can be met
or whether a waiver is appropriate.
2-40
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Compliance with action-specific ARARs (e.g., RCRA minimum technology
standards). It must be determined whether ARARs can be met or must be waived.
No chemical specific ARARs apply to the remediation of Site 19. Remedial Alternatives 1 and 2 will
not comply with chemical specific soil remediation levels established to protect human health and the
environment Furthermore, Site 19 soil may act as a source of potential contamination to underlying
groundwater and Virginia Groundwater Standards may not be attained. Alternatives 3,4,5, and 6 will
comply with soil RLs and will achieve all location-specific and action-specific ARARs.
2.8.2 Primary Balancing Criteria
Long-term Effectiveness and Permanence:
This criterion evaluated alternatives with respect to their long-term effectiveness and the degree of
permanence. The primary focus of this evaluation was the residual risk that will remain at the sites and
the effectiveness of the controls that will be applied to manage residual risks. The assessment of
long-term effectiveness was made considering the following four factors:
The magnitude of the residual risk to human and environmental receptors remaining
from untreated waste or treatment residues at the completion of remedial activities.
An assessment of die type, degree, and adequacy of long-term management
(including engineering controls, institutional controls, monitoring, and operation and
maintenance) required fat untreated waste or treatment residues remaining at the site.
AnassessmertofdKlong-tennreliabilityofenguieermgam
to provide continued protection from untreated waste or treatment residues.
The potential need for replacement of the remedy and the continuing need for repairs
to maintain the performance of the remedy.
Alternatives 1 and 2 are not effective or permanent because waste is left in place at Site 19.
Alternative 3 is permanent, but its long-term effectiveness is a function of future cover maintenance.
2-41
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Alternatives 4, 5, and 6 are effective and permanent because waste is removed from the site and
contamination is destroyed by biological processes or incineration.
Reduction of Toxicity. Mobility, or Volume Through Treatment
This evaluation criterion addressed the degree to which the alternatives employ treatment technologies
that permanently and significantly reduce toxicity, mobility, or volume of die hazardous substances.
Alternatives that do not employ treatment technologies do not reduce toxicity, mobility, or volume of
COCs. The evaluation considered the following specific factors:
The treatment processes, the remedies that will be employed, and the materials mat
will be treated.
The amount or volume of hazardous materials that will be destroyed or treated.
The degree of expected reduction in toxicity, mobility, or volume, including how the
principal threat is addressed through treatment
The degree to which the treatment will be irreversible.
The type and quantity of treatment residuals that will remain following treatment
Alternatives 1,2, and 3 do not employ treatment technologies which reduce toxicity, mobility or
volume. Alternative 3 (capping) would reduce potential mobility of contaminants to migrate vertically
or horizontally by not allowing precipitation to facilitate transport Again, the effectiveness of
Alternative 3 to preclude migration is dependent on the maintenance of die cover. Alternatives 4, 5,
and 6 do reduce toxicity, mobility and volume of waste at the she. Alternative 4 utilizes biological
treatment to destroy 2,4,6-TNT and RDX and produces relatively non-toxic intermediates such as
amino-dinhrotoluenes. Intermediates including amino-dinhrotoluenes are also destroyed as part of
the bioremediation process with time. Soil removed from the Site 22 biocell following treatment will
be certified as clean and placed on the ground at Site 22 fordewatering. There will be no residual
contamination (other than limited investigation derived waste [TOW]) associated with this alternative.
2-42
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Alternatives 5 and 6 reduce toxicity, mobility and volume at the site but residuals and soil subjected
to incineration will produce ash as a byproduct Ash produced by incineration technologies must be
disposed of properly.
Short-Term Effectiveness:
The short-term effectiveness of each alternative was evaluated relative to its effect on human health
and the environment during implementation of the remedial action. Potential threats to human health
and die environment associated with handling, treatment, or transportation of hazardous substances
were considered. The short-term effectiveness assessment was based on four key factors:
Short-term risks that might be posed to die community during implementation of an
alternative.
Potential impacts on workers during remedial action and the effectiveness and
reliability of protective measures.
Potential environmental impacts of the remedial action and the effectiveness and
reliability of mitigative measures during implementation.
Time until remedial response objectives are achieved.
Although dismantling of the conveyor bete and excavation activities could potentially expose workers
to contamination during implementation of Alternatives 3,4,5, and 6, these alternatives are protective
of human health and the environment in the short-term and could be completed wimin one year after
implementation. Of these alternatives. Alternatives 3 and 4 could be implemented most quickly
because an off-she permitted incineration facility is not necessary to begin remedial action.
Alternatives 1 and 2 are not protective in the short-term.
2-43
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ImplementabilJtv:
Implementabilfty considerations included the technical and administrative feasibility of each
alternative and the availability of various materials and services required for its implementation. The
following factors were considered during the implementability analysis:
Technical Feasibility: The relative ease of implementing or completing an action
based on site-specific constraints, including the use of established technologies, such
as:
ป Ability to construct the alternative as a whole (constructability).
ป Operational reliability or the ability of a technology to meet specified process
efficiencies or performance goals.
ป Ability to undertake future remedial actions that may be required.
ป Ability to monitor the effectiveness of the remedy.
Administrative Feasibility: The ability and time required to obtain any necessary
approvals and permits from regulatory agencies
or services required to implement an alternative, including:
ป Available capacity and location of needed treatment, storage, and disposal
services.
ป Availability of necessary equipment, spncuilrcfr, and provisions for necessary
additional resources.
ป Timing of the availability of prospective technologies under consideration.
2-44
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ป Availability of services and materials, plus the potential for obtaining bids
that are competitive (this may be particularly important for innovative
technologies).
Alternatives 5 and 6 can be implemented only if a permitted off-site incineration facility is available.
Alternatives 3 and 4 are readily implementable as are Alternatives 1 and 2.
Cost:
For each remedial alternative, a detailed cost analysis was developed based on conceptual engineering
and analyses. Unit prices were based on published construction cost data, quotes from vendors and
contractors, and/or engineering judgment Costs are expressed in terms of 1997 dollars. In order to
allow the costs of remedial alternatives to be compared on the basis of a single figure, the net present
worth (NPW) value of all capital and annual costs was determined for each alternative. The USEPA
CERCLA RI/FS Guidance Document recommends that a 5 percent discount rate be used in present
worth analyses. Of the treatment alternatives, Alternative 4 (Excavation/Biological Treatment/Reuse-
Recycle) is approximately $260,000 more expensive than Alternative 3 (Capping). Alternative 4 is
considerably lessexpensive than Alternative 5 (Excavation/Soil Washing/Incineration) and
Alternative 6 (Excavation/Off-Site Incineration).
2.8 J Modifying Criteria
State Acceptance:
The Commonwealth of Virginia was involved in the selection of the remedy for Sites 9 and 19.
Information regarding remedy selection was conveyed through Restoration Advisory Board (RAB)
meetings, the FS Report and at the public meeting. No state comments were received disputing the
final remedy. The Commonwealth is satisfied that the appropriate process was followed in evaluating
remedial action alternatives for Sites 9 and 19 and concurs with the selected remedy.
2-45
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Community Acceptance:
WPNSTA Yorktown solicited input from the public on the development of alternatives and on the
alternatives identified in the Proposed Plan. A public meeting on the Proposed Plan was held on
July 21,1997. The public is in agreement with the cleanup objectives. No additional information
on the Proposed Plan has been requested and the 45 day public comment period closed on
August 13,1997, with no additional comments being received on the selection of a remedy.
2.9 Selected Remedy
The selected remedy for Site 9 (OU VII) is no action.
The selected remedy for the cleanup of explosives-contaminated soil at Site 19 (OU VI) is
Alternative 4 (Excavation/Biological Treatment/Reuse-Recycle). This alternative is protective of
human health and the environment; complies with all ARARs; has a high degree of short-term and
long-term effectiveness and permanence; and reduces the toxicity, mobility, and volume of wastes to
be disposed of through removal, treatment, and reuse. Furthermore, Alternative 4 requires no
maintenance to ensure its long-term effectiveness, a draw back to Alternative 3 (Capping). Because
of bench-scale and pilot scale treatability studies conducted for explosives contaminated soil, it is a
demonstrated and easily imptementable technology and is significantly more cost effective than other
"treatment" technologies. Alternative 4 will not produce residual ash, a drawback to Alternatives 5
and 6 which utilize incineration technology. Alternative 4 is also the second least costly treatment
alternative evaluated during the remedial process. Table 2-18 presents the detailed costs for
Alternative 4.
2.10 Performance Standard
Alternative 4 requires the dismantling and disposal of the conveyor belt at She 19 and the excavation
of 2,4,6-TNT contaminated soil greater than or equal to 15 mg/kg and RDX contaminated soil greater
than or equal to 5 mg/kg. Soil shall be excavated along the entirety of the conveyor belt (and in the
near vicinity of the conveyor belt) to a depth of approximately 4 feet bgs. Contamination is not
believed to be deeper than 4 feet in depth (based on limited sampling), but samples shall be taken
throughout the area of excavation during remediation to confirm concentrations in underlying soil.
2-46
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TABLE MS
COST ESTIMATE: BAA Nป. 4 - EXCAVATION/BIOLOGICAL TREATMENT
srrci*
WfNSTA VORKTOWN. VORKTOWN. VIRCINU
COfT COWONCNT
UNIT
QUANTITY
UNIT
COST
COST
TOTAL
COfT
tOUKCB
BASIS/COMMINTS
DIRECT CAmAL COSTS
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11,000
10.000
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1.000
1
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1
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21.000
10.000
10.000
40.00*
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S 2.440
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SitcWoA. IW1.022-214
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TABLE Ml
COST ESTIMATE; BAA N*. 4 EXCAVATION/BIOLOGICAL TREATMENT
SITEI*
WfNSTA YOBKTOWN, YOUCTOWN, VIRGINIA
COST COMMNCNT
oncer CAMTAL com tcซซiMซ
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DIBBCT CAnTAI. COBTS TOTAL
INBUICT CATITAL com
t+*m*t~ปD**
INMBICT CAITTAL COd* TOTAL
CAMTAL COST* {DUUCT AMD INMBXCT)
TOTAL COST (PW| -BAAIto.4
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QUANTITY
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1
1
1
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S4JITOTAL
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BASIS 1 COMMENTS
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EnSysฎ test kits shall be used to obtain real time data in die field. Soil having exceedences of RLs
shall be removed and transported to the Site 22 biocell for biological treatment and reuse. Aluminum
detected in soil around Building 527 exceeding 14,830 mg/kg (the 95th percent UCL of Station-wide
background) shall be excavated to a depth of approximately 6 inches bgs (based on limited sampling).
The soil shall be placed in die deeper excavated area. Clean fill shall then be placed in all areas of
excavation and the area shall be regraded and vegetated to prevent erosion. The extent of 2,4,6-TNT,
RDX and aluminum contamination in soil shall be determined during remediation and sampling and
analysis information will be presented in the Remedial Action Work Plan.
Soil shall be treated biologically at Site 22 to the RL values used to determine the area of excavation
at Site 19. The soil shall men be dewatered and used as clean fill at Site 22, not Site 19. Currently,
property use is restricted by the location of the site (Site 19 is in the restricted area). Property use
restrictions shall be added to the Station Master Plan to preclude future residential development of
Site 19.
2.11 Statutory Determination
The selected remedy for Site 19 satisfies the requirements under Section 121 of CERCLA to:
Protect human healdi and the environment
Comply with ARARs.
Use permanent solutions and treatment technologies/resource recovery technologies
to the maximum extent practicable.
Satisfy the preference for treatment as a principle element
2.11.1 Overall Protection of Human Health and the Environment
Alternative 4 will provide a significant reduction in risks to human health and the environment at
Site 19 through the removal and on-site biological treatment of the soil contaminants. As such, this
2-49
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alternative will provide protectiveness to human health and the environment The potential source of
contamination to other environmental media will be removed.
2.11.2 Compliance with ARARs
The selected remedy for Site 19, Alternative 4, complies with all Federal and state location and action
specific ARARs as outlined below. Chemical specific ARARs or to-be-considered criterion (TBCs)
are not available for soil; therefore, risk-based RLs were developed that are protective of both human
health and the environment.
Location-Specific ARARs
Archaeological Resources Protection Act, 16 UJS.C 470aa-mm; National Historic
Preservation Act 16 U.S.C. 470 to 470 z-6
(16 U.S.C. 432,433; 32 CFR Parts 229 and 229.4; and 36 CFR Part 800)
Archeological resources encountered during excavation must be reviewed by Federal
and Commonwealth archaeologists. Also applies to potentially historic buildings.
Building 10 and Building 527 are World War II era buildings. The WPNSTA
Yorktown Environmental Directorate and Draft Historic Preservation Plan for
WPNSTA Yorktown should be contacted and reviewed prior to development of the
Remedial Action Work Plan.
Executive Order 11990 Protection of Wetlands
(40 CFR 6, Appendix A; excluding Sections 6(aX2), 6(aX4), 6(aX6);
40CFR6J02)
Action to minimize the destruction, loss, or degradation of wetlands that could be
impacted by a remedial action. Although no wetlands exist at Site 19, erosion from
excavation activities could migrate to Lee Pond. An erosion control plan will be
established as part of the Remedial Action Work Plan.
2-50
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Clean Water Act, Section 404,33 U.S.C 1344
(40 CFR 230.10; 40 CFR 231 (231.1,23U, 231.7,231.8))
Action to prohibit discharge of dredged or fill material into a wetland without a
permit if the discharge of dredge or fill is planned as part of the remedial alternative.
No material taken from either Site 19 or removed from the biocell after biological
treatment will be discharged into wetlands.
Virginia Wetlands Regulation
(VR 45041-0051/4 VAC 20-390-10 fit UQ.)
Regulates activities that impact wetlands. The remedial action will be undertaken in
such a way as to limit potential impacts on wetlands via erosion from Site 19 during
excavation and reuse of treated soil at Site 22.
Action-Specific ARARa
Department of Transportation Roles for Hazardou Materials Transport
(49 CFR Parts 107 and 171.1-560)
Regulates the transport of hazardous waste such as IDW including packaging.
shipping, and placarding for any remedial action that requires off-site treatment and
disposal. This ARAR applies only to hazardous wastes sent off-she for disposal such
as IDW generated during confirmation sampling. This ARAR does not apply to the
transportation of contaminated soil from Site 19 to Site 22.
Resource Conservation and Recovery Act (RCRA) Subtitle C,
(42U.S.C6921-ซ939e)
Applicable to any action at WPNSTA Yorktown utilizing the Site 22 biocell and any
action involving treatment, storage, or disposal of hazardous waste.
2-51
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Identification and Listing of Hazardous Waste
(40 CFR Part 261)
Wastes hazardous by characteristic must be identified as part of the remedial
action. Site 19 soil contaminated with 2,4,6-TNT and RDX is not
hazardous by listing.
Releases from Solid Waste Management Units
(40 CFR Part 264, Subpart F)
All units on-site will comply with substantive requirements concerning
potential releases.
Use and Management of Containers
(40 CFR Part 264, Subpart I)
Regulates the use and management of containers being stored at all
hazardous waste facilities. Remediation may generate containerized waste,
such as IDW. Alternative 4 reduces the use of containers because Site 19
i
soil will be treated at the Site 22 biocell. As such, containerization prior to
treatment is not necessary.
SurfaceJUnpoundments-
(40 CFR Part 264, Subpart K)
Regulates design, operating requirements, actions concerning leakage, rates,
closure, and post-closure care of the biocell at Site 22. This ARAR applies
to the Site 22 biocell, in particular the specifics concerning closure and post
closure care.
Closure and Post-Closure
(40 CFR Part 264, Subpart G)
Concerns the applicability of closure performance standards disposal,
certification of closure, and post-closure care of the Site 22 biocell. Also
concerns certification of completion of post-closure care at Site 22.
2-52
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Virginia Solid Waste Management Units
(VR 672-20-10/9 VAC 2040-10 ฃ| 9*4.)
Regulates the disposal of solid wastes and could apply to the off-site disposal of
nonhazaidous waste associated with the dismantling of the conveyor belt at She 19
and grubbing activities conducted prior to soil excavation.
Virginia Hazardons Waste Management Regulations
(VR 672-10-1/9 VAC 20-40-10 tf MS-)
Regulates the treatment, storage, and disposal of hazardous waste.
Identification and Listing of Hazardous Waste
(VR 672-10-1, Part HI)
Applies to determining waste types by characteristic. Soil at Site 19 is not
considered to be hazardous by listing, but may apply to IDW generated as
part of the conformation^ sampling for aluminum, 2,4,6-TNT and RDX at
Site 19.
Releases from Solid Waste Management Units
(VR 672-10, Part X, Section 10.5)
Applies to owners/operators of facilities that treat hazardous waste.
Regulates potential releases from all onsite solid waste management units.
Closure and Post-Closure
(VR 672-10, Part X Section 10.6)
Applies to the closure and post-closure care at the Site 22 biocell to prevent
escape of hazardous waste to the environment
Use and Management of Containers
(VR 672-10, part X, Section 10.8)
Applies to She 19 where the IDW associated whhconfirmational sampling
may be containerized before being disposed of offsite.
2-53
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Surface Impoundments
(VR 672-10, Part X, Section 10.10)
Applies to the Site 22 biocell where Site 19 soil will be treated. The Site 22
btocell should comply with substantive design and containment requirements
to prevent the release of waste to the surrounding environment Currently,
the biocell is double-lined to prevent releases to the environment Expansion
of the biocell (if necessary) should also include a double liner to prevent
releases from occurring.
Virginia Erosion and Sediment Control Regulations
(VR 625-02-00)
Applicable for remedial actions involving land disturbing activities. Activities
including the excavation at Site 19 will have an erosion control plan submitted to
Atlantic Division, Naval Facilities Engineering Command (LANTDIV) for approval.
2.11J Cost Effectiveness
Of the four "treatment" alternatives. Alternative 4 is the most cost effective. It provides maximum
long-term protection of human health and the environment and short-term protection of human health
and the environment with the least expenditure of funds.
2.11.4 Use of Permanent Solutions and Alternative Treatment Technologies or Resource
Recovery Technologies to the Maximum Extent Practicable
The selected remedy is a permanent solution and uses treatment technologies to the maximum extent
practicable. Contaminated Site 19 soil will be treated at the Site 22 biocell using a carbon source and
microbes to destroy 2,4,6-TNT, RDX and degradation products of nitramine compounds. Clean soil
will then be taken from the Site 22 biocell and used as fill at Site 22.
2.12 DocnmeBtatioaofSyaificaatChanfej
The Proposed Plan presents the selected remedy as the preferred alternative. No significant changes
to the remedy have been made.
2-54
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3.0 RESPONSIVENESS SUMMARY
The final component of this Record of Decision is the Responsiveness Summary. The purpose of this
section is to provide a summary of the public's comments, concerns, and questions about Sites 9
and 19.
During the public comment period, written comments, concerns and questions were solicited. A
public meeting was held on July 21, 1997 at the York County Recreational Services Building to
formally present the Proposed Plan and to answer questions and receive comments. The transcript of
this meeting is presented in Appendix A of this Record of Decision. All comments and concerns
concerning the remedy have been considered by the DoN and USEPA in the selection of the remedial
alternatives for Sites 9 and 19.
The responsiveness summary is divided into the following sections:
Overview
Background on community involvement
Summary of comments received during the public comment period
3.1 Overview
No action is necessary at this time to protect human health and the environment at Site 9. At the time
of the public meeting, the DoN endorsed a no action remedy for Site 9. The community agreed with
the no action remedy.
At the time of the public meeting, the DoN also endorsed a preferred alternative for the cleanup of
explosives-contaminated soil under the conveyor belt at Site 19, WPNSTA, Yorktown. The
alternative required a dismantling of the conveyor belt and proper disposal and excavation of soil
contaminated with 2,4,6-TNT and RDX at concentrations above RLs of IS mg/kg and 5 mg/kg,
respectively. This soil would be treated at the Site 22 bioceil using a carbon source and microbes to
biologically degrade 2,4,6-TNT and RDX. USEPA Region III and the Commonwealth of Virginia
concurred with the preferred alternative.
The community also agrees with the preferred alternative for She 19. An important factor in
community approval is on-site treatment of contaminated soil rather than off-site disposal.
3-1
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3.2 Background on Community Involvement
Nearby communities have a good working relationship with WPNSTA Yorktown because the Station
maintains a good neighbor policy through the Public Affairs Office. WPNSTA Yorktown participates
in community events and celebrations to foster close ties with the community. As part of the ongoing
Community Relations Program (CRP), community interviews were conducted in 1991 to inform the
community of the IR Program and solicit feedback on the listing of WPNSTA Yorktown as an NPL
site. The community expressed concern about three issues: water resources, cleanup funding, and
information availability/validity. This public openness has been maintained by the Public Affairs
Office and the Environmental Directorate at WPNSTA Yorktown through the CRP and resulted in
the formation of the RAB. The WPNSTA RAB is comprised of agency representatives, technical and
business persons, and members of the community at large. The RAB meets regularly and progress
at sites such as Sites 9 and 19 is discussed from the work plan stage to selection of the remedial
alternative (if necessary). Preliminary Site 9 and 19 results were discussed at past and at the most
recent RAB meetings. No significant comments were received for either site at these meetings.
3J Summary of Comments Received During the Public Comment Period
The Public Comment Period closed on August 13,1997. No additional comments on the proposed
remedy were received by WPNSTA Environmental Directorate personnel or LANTDIV personnel and
no additional comments were received during the July 21, 1997 Public Meeting.
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4.0 REFERENCES
Baker Environmental, Inc. 1997a. Final Explosives Contaminated Soil Pilot Study Report. Naval
Weapons Station Yorktown. Yorktown. Virginia. July 1997.
Baker Environmental, Inc. 1997b. Final Feasibility Study Report for Sites 9 and 19. Naval Weapons
Station Yorktown. Yorktown. Virginia. June 1997.
Baker Environmental, Inc. 1997c. Final Round Two Remedial Investigation Report for Sites 9 and
19. Naval Weapons Station Yorktown. Yorktown. Virginia. January 1997.
Baker Environmental, Inc. and Roy F. Weston, Inc. (Baker/Weston). 1993. Final Round One
Remedial Investigation Report for Sites 1-9. II. 12. 16-19. and 21. Naval Weapons Station.
Yorktown. Virginia. July 1993.
C.C. Johnson & Associates, Inc. And CH2M Hill. 1984. Initial Assessment Study of Naval Weapons
Station. Yorlrtown. Virginia. July 1984.
Dames & Moore. 1989. Draft Remedial Investigation Interim Report. Naval Weapons Station.
Yorktown. Virginia. February 1989.
Dames & Moore. 1988. Confirmation Study Step IA (Verification 1 Round Two. Naval Weapons
Station. Yorktown. Virginia. June 1988.
Dames & Moore. 1986. Confirmation Study Step IA (VerificationV Round One. Naval Weapons
Station. Yorktown. Virginia. June 1986.
Department of the Navy (DoN). 1991. The Master Plan for the U.S. Naval Weapons Station.
Yorktown. Atlantic Division, Naval Facilities Engineering Command, Norfolk, Virginia.
Federal Facility Agreement under CERCLA Section 120 (FFA). 1994. United States Environmental
Protection Agency, Commonwealth of Virginia, and the United States Department of the Navy.
Administrative Docket Number III-FCA-CERC-009. August 4,1994.
4-1
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TaJinage, Sylvia S,Ph.DA.B.T. and Dennis M.Opresko. 1996a. Ecokxric.. r*^ fy1lfnrnT fnr
2.4.6-TrinitrntoluซiC (Draft) Oak Ridge National Laboratory. Oak Ridge, Tennessee. May 1996.
Talmage, Sylvia S., Ph.D A.B.T. and Dennis M Opresko, Ph.D 1996b. Ecological Criteria rw.fnifnt
for Hexahvdrn-1.3.S.TrimtT^L3.S.Triazine fMปO (DraftV Oak Ridge National Laboratory, Oak
Ridge, Tennessee. May 1996.
U.S. Army Corps of Engineers. 1990. Draft Historic Preservation Plan Weanons Station Y^Kt^
Yorktown, Virginia. Army Corps of Engineers Mobile District
Versar. 1991. Remedial Investigation Interim Report. Naval Weapons Station. Yorictnwn. Virginia
July 1991.
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APPENDIX A
PUBLIC MEETING MINUTES
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4 PUBLIC MEETING FOR THE
5 PROPOSED REMEDIAL ACTION FOR
6 SITES 9 AND 19
7 NAVAL WEAPONS STATION YORKTOHN
8 YORKTOHN, VIRGINIA
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10 Presentation by Richard Hoff
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301 Goodwin Neck Road
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MS. PHILLIPS: Ladies and gentlemen,
we're going to call to order the Public Meeting to
review the Proposed Remedial Action for Sites 9 and
19 at Naval Weapons Station, Yorktown, as part of
their ongoing cleanup procedures, and this is under
the leadership of Mr. Jeff Barlow, and the contractor
is Baker, and our speaker is Mr. Rich Hoff.
MR. HOFF: Thank you. I'm not going
to tell you anything that you don't know. First of
all, I appreciate the opportunity to come .down,and
11 talk to you. I'm glad the Navy and Jeff and Rick
asked me to come down, and glad to be here.
Tonight's meeting is to inform the
public about potential risks, and the proposed
remedies for Sites 9 and 19. We're trying to elicit
comments from the public about the proposed remedy,
and address any concerns that the public might-have.
This is about the halfway point in
19 if. the public comment period. To that extent, we're
20 I going to provide a fact sheet for the remedy at Sites
9 and 19. We're also going to provide a-fact sheet
for the remedial action at Site 12 to let.you-all
know that remediation of Area A. is. imminent. 'That
should be happening within the next couple of months,
I'11 give you a little brief- '
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1 description of both Sites 9 and 19. Site 9 was Plant
2 1, Explosives Contaminated Discharge Area. And if
3 you go to the board, there are some figures with
4 pictures of both Sites 9 and 19. In essence, Site 9
5 is a ditch. It received discharge from Plant 1 for
6 about forty years. This discharge ultimately entered
7 Lee Pond. Lee Pond is not the subject of this
8 investigation. Lee Pond will have its own
9 investigation in the latter fiscal year 1997 and
10 early fiscal year 1998. . .. ....
11 In 1975, the discharge from Plant 1
12 was sent to the Carbon Absorption Tower. It. was
13 installed to treat the water prior.to discharge, and
14 that discharge was permitted. .. In '86, the. tower.was
15 removed and the discharge then went .to.HRSD, or the
16 Hampton Roads Sanitation District. .
17 In 1994, there was a removal action
18 of some debris and soils and sediment at the bottom
19 of the discharge area. And the area was sampled,
20 back-filled, and regraded. . <
21 Site 19 is the conveyor belt, and
22 ' primarily the soil under the conveyor belt at
23 Building 10 or Plant 1. As the name would suggest,
24 the conveyor belt transported TUT and other
25 explosives from Building 98 to Building 10 during
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loading operations. TNT and other explosives were
released to surrounding soil as either dust, or by
the routine spraying of the interior of the belt.
When dust built up inside there, it was sprayed with
water, and this water was allowed to drip to the
underlying soil.
Aluminum powder I have a typo
here; I tried to correct it was also used in the
loading process. Aluminum was handled and added to
the line at Building 527, and those buildings are
also outlined on the figures on the board.
There was an undocumented quantity
of soil removed, and I assume this was a voluntary
removal performed by the Station in 1973, 1974 prior
to any of the documentation processes that we use
currently under the IR Program.
MR. MARKHITH: We don't know where
it went, right, Rich? . .
MR. HOFP: I have no information.
MR.- THOMPSON: County landfill.
MR. MARKWITH: We'll hear about that
later, I'm sure.
MR. HOFP: Just to give you an idea
of the investigations that have taken place at. Sites
9 and 19, I think we have a pretty good handle on
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what's happening out there. There was an Initial
Assessment Study conducted in 1984. Confirmation
Studies, both Round One and Round Two were conducted
in 1986 and 1988; and these were the first
investigations where any data were collected that we
6 || began to evaluate as part of the IR program.
That data was summarized and the
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findings in the IR, Interim Report, Versar, 1991.
That report was initially made public in 1989; and as
part of the TRC and moving to a RAB, there were .some
public comments on that document, and the document
was subsequently modified and re-released. .. ; .
The most recent investigation is the
14 Round One investigation, Remedial Investigation..
15 That was conducted by Baker. A Treatability Study
for the Characterization Sampling, and this was as
we began to go through the process of evaluating
bio-remediation options, we knew Sites 9 and 19 had
19 potential TNT contamination associated with them.from
20 I! the prior investigations, so there was a grid
21 II overlaying at both Sites 9 and. 19, and composite
samples were taken along those grids, and that
allowed us to collect representative soil and send it
off to West for some of the early bench scale
studies.
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After the Treatability Study
Characterization, we had the Round Two Remedial
Investigation; and the Round Two Remedial
Investigation focused on those areas that were
identified in the Round One in a Treatability
Characterization Sample as needing additional
investigation.
After the Round Two RIr there was
still some concerns about the data, being that we
knew we had composite samples with relatively high
hits, but we weren't seeing the same high hits in
discrete samples that we took for the Round Two RI.
This is simply the nature of explosives contaminated
media. It's sort of hit and miss.
Subsequent to the Round Two Remedial
Investigation, we then went back out with test kits
that delineate site areas of concern. At that time
we got underneath the. conveyor belt. We went to
those areas that were hot spots in both Round One and
where some composites showed some potential problems
during the Treatability Characterization Sampling.
I'm going to start with the Round
Two Remedial Investigation. I'm not going to take
you back to the Round One. Some of the Round One
data was used for baseline risk assessment. The
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Round Two Remedial Investigation was really the
backbone of the data that was used in the
assessments. They were conducted in September and
October of 1995. It's the most recent data that we
have.
We collected surface soil,
7 subsurface soil data, groundwater data at both Sites
9 and 19. At Site 9 we also collected surface water
and sediment from the ditch. The samples were
analyzed for the full sweep of contaminants., . The
target compound list organics, TAL, or Target Analyte
List, inorganics, the nitromines/nitroaromatics,. or
explosives, and cyanide. We also obtained benthic
macroinvertebrate samples from the sediment of the
15 Site 9 drainage area-.
16 Because of the nature of that area,
17 the data was somewhat equivocal. She ditch dries* up
from time to time; and AS such, it really doesn't
provide a great habitat for collecting benthic .
organisms. It would really depend on the time of the
year, and we compromised with EPA .about how to
prevent this fish sampling. We usually straddle the
later summer when it's a so-so time for both fish and
benthic to be present.
Again, Lee Pond was not
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1 investigated. And most importantly, with the Round
2 Two investigation, we did a quantitative baseline
3 risk assessment that evaluated both human health and
4 ecological evaluations.
5 The Baseline Risk Assessment
6 utilized data from Round One and Round Two RIs. We
7 evaluated human receptors, both current and future
8 potential human receptors, including residents.
9 These were considered, both from an additive
10 standpoint, and individually, in that we evaluated
11 children and adults living on site; and again, we
12 also considered the most likely use of the property,
13 the commercial or industrial property use scenarios.
14 . Potential residents, or future
15 potential residential exposure considered both a
16 potable use of groundwater, and a nonpotable or ,
17 beneficial use of the underlying aquifer. The reason
18 being that through the investigative work that we've
19 done at the Station, and also some of the work that
20 USGS has done out there, the aquifers that are
21 directly underneath most of our sites, and those
22 would be from primarily Cornwallis Cave and Yorktown
23 East over, are not of sufficient quality that they can
24 be used for potable purposes without some sort of
25 pretreatment. And when I say the Upper Yorktown, I'm
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talking about Yorktown and counties directly below
that clay between Cornwallis Cave and the Yorktown
3 Aquifer, probably about 30, 35 feet in depth.
4 II As we go down through the Yorktown
5 East over/ we encounter a tightening of the materials,
6 and also yield becomes a problem in that aquifer. I
7 think if you, at least from the Station's standpoint,
8 have to go somewhat deeper to ever really want to use
9 water potability from that system.
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In general, we considered Exposure
at Sites 9 and 19, there was no unacceptable human
health risks associated with Site 9 soil, surface
water, or sediment.
Again, from the groundwater
standpoint, beneficial use scenarios did not really
pose unacceptable human health risks because when we
assume a beneficial use, we're looking at something.
like lawn watering, washing of cars. He don't have
that ingest ion of two liters per day for 25. years,.
20 350 days per year. So if we do evaluate the potable
21 II use of groundwater, we do have unacceptable human
22 || health risks associated with it. There are some
relatively low levels of explosives and volatile
compounds in the shallow. These attenuate somewhat
as we go down.
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1 Again/ groundwater around this area
2 will be reevaluated as we investigate the pond,
3 because one of our concerns is this groundwater could
4 discharge from Lee Pond, and we haven't adequately
5 evaluated the ecological impact associated with that.
6 Site 19 soil produced unacceptable
7 human health risks to both workers and future
8 residents. Those are the soils under the conveyor
9 belt, and also one smaller area of concern on the
10 other side of Building 97. And we're assuming just
11 from past operations, the offloading and so forth,
12 that TNT dust was able to get into that area and it
13 appears to be limited to the top six inches or so of
14 soil.
15 The Economical Risk Assessment was
16 actually conducted twice. The first time we used a
17 method that we had established sometime ago in the
18 Master Work Plan, and most recently through- formal
19 partnering. We have been in consultation with the
20 EPA Biological Technical Assistance Group. We've
21 worked out new procedures for evaluating the
22 ecological risks. What we've done is we've gone back
23 to the basics, gone backs to the Draft Ecological
24 Risk Assessment Guidance. It's a 1994 document where
25 you use a very conservative screening approach with
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relatively low numbers to evaluate your chemicals of
concern/ and then you take a look at all the
potential receptors, not only terrestrial, but
aquatic receptors if necessary. You break out those
receptors in terms of trophic development, and then
you conduct very conservative modeling. And so
7 II you'll find this Risk Assessment in Appendix B of the
8 Final FS.
9 The kind of breakdown, the types of
10 receptors we were looking at, we looked at
11 terrestrial receptors, which included the soil
12 invertebrates; plants; robins; red-tailed hawks, and
13 short-tailed shrews; and meadow voles.
14 The aquatic receptors really applied
15 to Site 9, and it was a little bit of a stretch
16 because of the nature of the ditch. He looked at
17 fish, including the catfish. He evaluated for
18 sediment benthic macroinvertebrates. From the
19 II standpoint of comparative criteria, we didn't
20 evaluate the benthic data that we had. That data is
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in the Final Remedial Investigation Report, but we
did not evaluate that in the Final FS report.
He use that from the standpoint of
evaluating what we had out there, what we expected to
see, but the screening for the aquatic receptors waa
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done using a comparative criteria approach. We
evaluated bullfrogs, and then finally the great-blue
herons. Again, these receptors were selected to
represent various trophic levels, or the food chain,
if you will.
The result of the Ecological Risk
Assessment indicated the presence of lead and
vanadium in Site 9 soils produced unacceptable risk
to robins and shrews. Aluminum, iron, lead and TNT
in Site 19 soils produced risks to the robin and
shrew. Aluminum also produced risk to the vole.
There was also one detection of iron in the Site 9
drainage-way that gave STAG some concern, but that
sample was in one location at the bottom of the
drainage-way. It was also at a depth; it was at the
4 to 8-inch depth level. As we talked about it, the
concerns became less and less less and less
apparent, because we feel that at the 4 to 8-inch
depth interval, you're really precluding the type of
exposure that the model was run for, and that was the
model of the great-blue heron.
To summarize the Site 9 and 19
Baseline Risk Assessment, at Site 9 there were no
unacceptable human health risks. There was a limited
economical risk; and the reason we say limited is
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that the presence of the inorganics were detected
sporadically. There wasn't a real source area we
could get our hand around and identify. And there's
4 also the limited nature of the type of exposure. The
5 iron in the sediment was deep, so the receptor that
6 was posing a risk; i.e, the heron, we don't feel
7 could really be exposed to iron at that particular
8 depth.
9 II At Site 19, there were unacceptable
10 risks to both human health and the environment posed
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and lead contributed to the unacceptable ecological
risk. Aluminum was used again at Building 527, and
so along the sides of Building 527 you had some
aluminum hits that were greater than 95 percent UCL,
upper confidence level, of station-wide background.
And because of this, we identified that as a
potential area of concern in the FS.
The lead wasn't broken out because
lead really existed in the presence of the 2, 4, 6
TNT, and there were two or three locations along the
belt where the TNT was pretty high, and you also had
the lead. He felt that was not really a significant
source of lead at the site, other than the paint that
might have come off the conveyor belt.
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1 Using the results of the Baseline
2 Risk Assessment, we went into the selection of the
3 preferred alternative, and that's what we're here
4 tonight to present and to solicit comments from
5 you-all.
6 When you do this, you go through the
7 results of the Baseline Risk Assessment, you
8 summarize those results, and then you develop some
9 . general response actions, and the response actions
10 are usually broad-based evaluations of medium
11 specific responses that would satisfy remedial action
12 objectives.
13 In this case, based on the Baseline
14 Risk Assessment and formal partnering, we believe
15 that the Remedial Action Objective of Sites 9 and 19
16 is mitigating human health and ecological risks
17 associated with Site 19 soil. We call that Operable
18 Unit 6. We believe that no action is necessary to
19 mitigate risks at Site 9. One, because of the fact
20 there was no human health risk, either current or
21 future potential risk. Two, the ecological risks
22 were from the sporadic detection of inorganic
23 constituents. There was no real source area. And
24 after talking with the engineers, we felt that
25 remediation of the Site 9 soil supposed that
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ecological risk might be more detrimental to the
2 overall environment.
3 Building off the general response
actions, we began to apply five general actions at
the Site 19 soil. One was no action. We're required
to evaluate that. One was institutional controls.
Another response action is containment. A fourth was
8 in situ treatment, and that fell by the by for a
number of reasons. And the fifth was
10 removal/treatment/disposal. And you see that I've
11 sort of grouped these, because what we did, we
12 evaluated a lot of these process options using a
13 matrix approach, and that is available in the Final
14 Requests Report.
15 It shouldn't be any surprise, then,
16 that the remedial action alternative developed for
17 Site 19 were very similar to the objectives that we
18 proposed. Again, no action, because we're required
19 to evaluate no action in a baseline scenario. The
20 second remedial action alternative, or RAA 2, was no
21 action with institutional controls. The third is
22 capping. The fourth is excavation, biological
23 treatment, and then reuse or recycle of those soils.
24 The fifth was excavation, soil washing, incineration
25 of residuals that would be associated with soil
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washing, and then reuse and recycle of the washed
soil, and the fifth was the gross excavation,
off-site incineration; i.e., the hog and haul.
As part of the FS, we then evaluated
each one of the Remedial Action Alternatives using
threshold criteria, balancing criteria, and modifying
criteria. The threshold criteria really evaluates
the protectiveness. You look for ARARs, applicable
relevant appropriate requirement, on the books out
there that would force you to take an action and
address it. If not, then we always look at
protection of human health, and then finally, last
but not least, the environment. Is it protective of
the environment.
Balancing criteria is sort of the
engineering-type of criteria, short and long-term
effectiveness, two, reduce the toxicity through the
use of the remedy. Can we implement? What's the
time to implement? And how much does it cost?
And modifying criteria, that's what
we're here tonight for, is to get the community
acceptance in our selection of the remedy, and also
seek state acceptance.
When we evaluate the threshold
criteria, it becomes very apparent that RAAs 3, 4, 5
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and 6 comply with protectiveness, or we can attain
remediation levels, because there are no real ARARs
to the soil, we developed remediation levels backing
out the baseline risk, and we used both the
ecological goals, the literature values for toxicity
that were available, and also back calculation from
the human health risk assessment to come up with our
Remediation Levels.
It should be no surprise that RAAs 1
and 2 do not really comply with threshold criteria.
You're not taking an action, you're precluding
contact with an institutional control by putting a
fence up or telling people don't go there, but it
doesn't really do anything to mitigate the overall
risk that's associated with the site, specifically
not the ecological receptors.
The balancing criteria, RAA 1, 2 do
not result in reduction of toxicity, mobility or
19 volume of the chemicals left on site. Fence doesn't
20 I] keep precipitation from infiltrating and moving
21 || things around. And they would not be effective in
22 H the short-term and the long-term.
RAA 3, the capping alternative, does
not result in reduction of toxicity or volume, but it
does preclude exposure. The long-term effectiveness
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1 can be problematic, particularly for Jeff on the
2 station in that it's only as good as the operation
3 and maintenance of the cover. If the cover is
4 allowed to become compromised, if it's not
5 maintained, then it isn't a very protective
6 alternative.
7 RAAs 4, 5, and 6 obviously will
8 result in reduction of toxicity because we're going
9 to pick that soil up and move, we're going to take it
10 out of there. With 5 and 6, the implementability is
11 somewhat of a question because any incineration
12 technology depends on the availability of a permanent
13 facility to accept your waste. Then there's always
14 the problem of transporting the waste to that
15 location.
16 We believe that RAA4 is the most
17 implementable and cost effective because we have
18 biocell on site. We've proven through the bench
19 scale treatability studies that were conducted by
20 . West, and the pilot scale treatability study that we
21 completed last year, that this is an effective
22 alternative, and cost effective as well.
23 With RAA 1 or 2, we don't believe we
24 could get the buy-in from the public. Certainly once
25 the public has read the Risk Assessment, I don't
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1 think many would want us to leave the soils under the
2 conveyor belt at Site 19.
3 And Remedial Action Alternative 2,
4 putting up a fence is not going to prevent the
5 ecological risk associated with the explosives
6 contaminated soil/ and it's also not going to
7 preclude the ability of these contaminants to move.
8 They can move by overland runoff and certainly
9 infiltrate the background water.
10 Again, we'll be evaluating Lee Pond
11 later on in this year. I think it would be
12 wouldn't be- very prudent to leave a potential source
13 at Site 19 and then do an investigation at Lee Pond
14 if/ in fact/ this could be a potential source of
15 groundwater/ and ultimately an Ecological Assessment
16 needs to be done.
17 We weren't too sure about the
18 Commonwealth of Virginia and community acceptance of
19 RAA 3. I don't think that the state would want a
20 bunch of landfills at Weapon Station, nor do I think
21 Jeff wants to be in the business of managing caps and
22 covers for the rest of his life; and, again, toxicity
23 'is not reduced, and the long-term effectiveness is
24 dependent on the O & M.
25 Another problem for us with RAA 5
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1 and 6 is getting any type of public buy-ins for
2 incineration technology. There is just a stigma
3 behind incineration that it's not insurmountable,
4 but I think when you have biological treatment, like
5 we do on-site, we can evaluate these alternatives,
6 and we can see whether or not they are cost effective
7 for us. In this case, they're not. I would say that
8 both RAA 5 and 6 were anywhere from two and-a-half
9 times to five times as costly as the alternative,
10 which is RAA 4.
11 And again, the time .to implement RAA
12 4 well, as soon as we can get the funding done and
13 get the work plans done, we can begin to take an
14 action; whereas, with 5 and 6, we would have to,
15 again, be on-line with an off-site incinerator
16 facility that is permitted to accept the waste.
17 Again, the preferred alternative is
18 RAA 4. We're hoping we can get the buy-in from the
19 Commonwealth and from the public at large. It is
20 protective of human health. We believe it meets all
21 ARARs. And it's permanent in terms of removing
22 contaminants. We remove the toxicity by removal of
23 contaminants. It's a destruction technology. You're
24 not going to leave any residues. Even the byproducts
25 of the biodegradation are themselves degraded with
FOX REPORTING
21 Michael's Woods Drive, Hampton, Virginia 23666
(804) 827-7843
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1 time. And it's implementable, and we believe it's
2 cost effective.
3 And again, to touch base, and let
4 you know the fact sheet for the Proposed Remedial
5 Action is available, as well as the Site 12 Remedial
6 Action. The public comment for this remedy at Site 9
7 and 19 closes August 13, 1997.
8 I thank you for your time, and I'll
9 take any questions that yon might have.
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FOX REPORTING
21 Michael's Woods Drive, Hampton, Virginia 23666
(804) 827-7843
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COMMONWEALTH OF VIRGINIA
COUNTY OF YORK, TO-WIT:
I, ANNA M. FOX, a Notary Public in and for
the Commonwealth of Virginia at Large, do hereby
certify that the foregoing deposition was duly taken
and sworn to before me at the time and place in the
caption mentioned, and that the deposition is a true
record of the testimony given by the witness.
I further certify that I am neither
attorney or counsel for, nor related to or employed
by, any of the parties to the action in which this
deposition is taken, nor am I a relative or employee
of any attorney or counsel employed by the parties
hereto, nor am I financially interested in this
action.
IN WITNESS WHEREOF I have hereunto set my
hand and affixed my notarial seal this 25th day of
August, 1997. \
Anna M. Fox, Notary Public
My term of office expires: January 31, 2000.
FOX REPORTING
21 Michael's Woods Drive, Hampton, Virginia 23666
(804) 827-7843
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