PB99-963917
EPA541-R99-060
1999
EPA Superfund
Record of Decision:
Langley Air Force Base/
NASA Langley Center OU 50
Hampton, VA
9/27/1999
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RECORD OF DECISION
LANGLEY AIR FORCE BASE
OPERABLE UNIT 50
August 1999
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RECORD OF DECISION
LANGLEY AIR FORCE BASE
OPERABLE UNIT 50 (Sfte-61)
DECLARATION
SITE NAME AND LOCATION
Langley Air Force Base
Operable Unit 50 (Installation Restoration Program [IRP] Site 61)
Hampton, Virginia
STATEMENT OF BASIS AND PURPOSE
This Record of Decision (ROD) presents the selected remedial action for IRP Site 6 1 designated
Operable Unit (OU)-50, at Langley Air Force Base in Hampton, Virginia (the "Site")' chSSfa
^IVan omPre^s7 Enfonmental Response, Compensation, and lability Act
m A w ' "I"*??' U'S'C- 9601 etseq- md> to the extent P«afcabto, the
National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 40 Code of Federal
Regulations Part 300. This decision is based on the Administrative Record for this OU.
The Virginia Department of Environmental Quality concurs with the selected remedy.
DESCRIPTION OF THE SELECTED REMEDY
OU-50 is part of a comprehensive environmental investigation and cleanup currently being
performed at Langley AFB under the CERCLA program. This ROD addresses only OU-50- the
other OUs located at Langiey AFB are being investigated separately under its installation '
restoration program and either have been or will be addressed in other RODs. Also this ROD
identifies the final action for soils and an interim action for ground water at the OU ' Ground
water will be addressed in a final action on an installation-wide basis as a separate OU.
This action addresses the principle threat at the OU by imposing land use restrictions that will
prevent any non-industrial activities from taking place at this location. In addition, the interim
ground water action will prevent any use, other than monitoring, of the ground water at the OU
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The selected remedy is the implementation of institutional controls and monitoring and includes:
1) .Land use restrictions to prevent non-industrial use of the property, with the
exception of the non-residential waterfront development plans as discussed in
Section VT of this ROD and to maintain the integrity of the current asphalt
parking lot;
2) Ground water use restrictions to prohibit use of the ground water for purposes
other than monitoring;
3) Within 90 days of ROD signature, the Air Force shall produce a survey plat
prepared by a professional land surveyor registered by the Commonwealth of
Virginia indicating the location and dimensions of OU-50 and the extent of soil
and ground water contamination;
4) The Air Force shall supply a copy of the plat and ensure the incorporation of
these restrictions into any real property documents necessary for transferring
ownership from the United States, in the unlikely event that the United States
sells or transfers the property. The real property document would also include a
discussion of the National Priorities List (NPL) status of this Site, as well as a
description of the soil and ground water contamination. The Air Force shall
submit the survey plat to the City of Hampton recording authority for the limited
purpose of providing public notice of the environmental conditions of and
limitations on the use of the property. No property right or interest is intended to
be nor shall be created by such notice. In addition, the Air Force shall enter a
note, in the local land recording office, to the real property document evidencing
U.S. ownership of the property on which the OU is located that shall notify
interested parties that the site was previously used to manage paint shop
substances and waste;
5) Ground water monitoring to ensure contaminated ground water is not
impacting the Back River. Specifics of the monitoring program will be
developed by the Air Force, the United States Environmental Protection Agency
and the Virginia Department of Environmental Quality and presented in a
monitoring plan.
DECLARATION OF STATUTORY DETERMINATIONS
The selected final remedy with regard to soils 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 soils
remedy utilizes permanent solutions and alternative treatment (or resource recovery) technology
to the extent practicable for OU-50. With respect to groundwater contamination, the interim
measure is protective of human health and the environment and is cost-effective. Because this is
an interim measure, ARARs are waived and will be addressed under the final measures presented
in the future groundwater ROD. This portion of the action is interim and is not intended to
utilize permanent solutions and alternative treatment (or resource recovery) technologies to the
maximum extent practicable. Because this portion of the action does not constitute a final
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remedy for the ground water, the statutory preference for remedies that employ treatment that
reduces toxicity, mobility or volume as a principal element will be addressed by the final ground
water response.
Because this remedy may result in hazardous substances remaining on-site above health-based
levels, a review will be conducted within 5 years after commencement of the remedial action to
ensure that the remedy continues to provide adequate protection of human health and the
environment.
This 5-year review will also include an evaluation of the status of the ground water remedy to
determine if deed restrictions related to groundwater can be removed when ground water
response actions are completed.
THOMAS J. KE£gy Date
Lieutenant General, USAF
Vice Commander
ABRAHAM FERDAS Date
Director
Hazardous Site Cleanup Division
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TABLE OF CONTENTS
Section page
I. Site Name, Location, and Description \
H. Site History 2
in. Highlights of Community Participation 2
IV. Scope and Role of Operable Unit 4
V. Summary of Site Characteristics and Extent of Contamination 4
VI. Current and Potential Future Site and Resource Uses 7
VII. Summary of OU Risks 9
Vffl. Description of Alternatives 12
EX. Summary of Comparative Analysis of Alternatives 15
X. Selected Remedy 20
XI. Statutory Determinations 22
XLI. Significant Changes from Proposed Plan 23
XHL Responsiveness Summary 24
XIV. References 27
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APPENDIX A
Table Title
1 Summary of Operable Units Under CERCLA Investigation
2 Maximum Soil Concentrations Exceeding Industrial Screening Levels
3 Maximum Groundwater Concentrations Exceeding Residential Tap
Water Screening Levels
APPENDIX B
Figure Title
1 Location Map, Langley Air Force Base, Virginia
2 Base Map of Langley AFB Showing the Location of the Site (SS-61)
3 Soil and Ground Water Sampling Locations, Site 61 RI, Langley AFB
4 Waterfront Development Plan
APPENDIX C
Glossary
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List of Acronyms
AFB
ARAR
bgs
CE
CERCLA
COPC
°F
DOD
EEQ
EPA
GMF
ffl
IRP
IT
LUC
LUCIP
MOALUC
msl
MWR
NCP
NPL
O&M
OU
PCB
ppm
RAGS
RBC
RI
ROD
RME
TMV
UST
Air Force Base
applicable, relevant and appropriate requirements
below ground surface
Civil Engineering
Comprehensive Environmental Response, Compensation, and Liability Act
chemical(s) of potential concern
degrees Fahrenheit
U.S. Department of Defense
environmental effects quotient
U.S. Environmental Protection Agency
granular media filtration
hazard index
Installation Restoration Program
IT Corporation
Land Use Control
Land Use Control Implementation Plan
Memorandum of Agreement on Land Use Control
mean sea level
Morale, Welfare, and Recreation
National Oil and Hazardous Substances Pollution Contingency Plan
National Priorities List
Operations and Maintenance
Operable Unit
polychlorinated biphenyl
part(s) per million
Risk Assessment Guidance for Superfund
risk-based concentration
remedial investigation
Record of Decision
Reasonable Maximum Exposure
toxicity, mobility and/or volume
Underground Storage Tank
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Versar Versar, Inc.
VDEQ Virginia Department of Environmental Quality
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RECORD OF DECISION
LANGLEY AIR FORCE BASE
OPERABLE UNIT 50 (Site-61)
DECISION SUMMARY
' Site Name. Location, ?nd Descriptfoq
Langley Air Force Base (LAFB) is an active U.S. Department of Defense (DOD) installation
located approximately 180 miles south of Washington, DC, and is part of the Norfolk
metropolitan area (Figure 1). The Base sits on a peninsula bounded by the northwest and
southwest branches of the Back River (Figure 2), which is a tributary of the Chesapeake Bay. In
addition to the 3,152-acre Base installation, Langley AFB supports the 284-acre Bethel Manor
Off-Base Housing Area. Langley AFB was proposed to be included on the National Priorities
List (NPL) in 1993 and finalized in 1994. This list includes sites where uncontrolled hazardous
substance releases may potentially present serious threats to human health and the environment.
Operable Unit 50 (OU-50) was one of the Installation Restoration Program (IRP) sites
investigated under Comprehensive Environmental Response, Compensation, and Liability Act
(CERCLA) at Langley AFB and was initially designated IRP Site 61.
OU-50 is located in the southeastern portion of LAFB and is situated on the Southwest Branch of
the Back River. As shown in Figure 3, the 2-acre OU is bordered by the Base Marina to the
south, buildings to the west and northwest, staffi'marina parking to the north and northeast, and
the Back River to the east. Current land use at OU-50 is categorized as industrial and is expected
to remain industrial in the future.
OU-50 consists of two areas of concern:
The former Civil Engineering (CE) Paint Shop includes Building 615 and a fenced-in
gravel area that had been used for the storage of paint thinner and paint, the mixing of
paints, and the cleaning of painting equipment. The CE Paint Shop was in operation
from the 1950's to early 1991. The OU is now occupied by Morale, Welfare and
Recreation (MWR) for the administration of the Base Marina.
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To the east of the CE Paint Shop is an area where a 2,000 underground storage tank
(UST) was removed in 1993. The UST contained unleaded gasoline and was used for
fueling boats at the Base Marina.
II. Site History
This section describes the history of OU-50 and regulatory activities conducted to date.
A. OU History
OU-50 was originally identified in June 1992 when, during a discovery inspection for the
Morale, Welfare, and Recreation (MWR) office, indications of soil contamination from paints
and solvents was uncovered. An area that contained discharge residue from a water-jacketed
paint spray booth was also discovered. Evidence of stained soil was visible at the OU. An UST
at the marina adjacent to OU-50 leaked gasoline that was suspected to have spread into the area
of the site. The UST and some of the surrounding soil was excavated in early 1993.
During the removal of the marina UST, fill material was encountered, including creosote-treated
pilings, paint containers, and other refuse. Due to the discovery of this material, the OU was
expanded to include buried waste as well as the UST. Analysis of ground water samples
obtained from five monitoring wells installed during UST site characterization revealed the
presence of petroleum hydrocarbons.
B. CERCLA Investigations
Under CERCLA, a remedial investigation (RI) was conducted from 1995 through 1998. This
investigation was performed to characterize the nature, magnitude and extent of contamination at
OU-50, determine what risks to human health and the environment existed at OU-50, and
determine if further action was necessary for OU-50. Results of the RI are discussed in section
V(B).
Ill- Highlights of Community Participation
In accordance with Sections 113 and 117 of CERCLA, 42 U.S.C. Sections 9613 and 9617,
Langley AFB, in conjunction with the EPA and the Virginia Department of Environmental
Equality (VDEQ), issued a proposed plan on November 30, 1998, presenting the preferred
remedial alternative for OU-50. The Proposed Plan and supporting documentation were made
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available for review at that time and are among the documents that comprise the CERCLA
Administrative Record for the Site.
The Administrative Record is available for review by the public at the following information
repositories:
Hampton Public Library
4207 Victoria Boulevard
Hampton, Virginia 23669
(757)727-1154
LangleyAFB
Contact: Mr. Vern Bartels
1CES/CEVR
37 Sweeney Boulevard
Building Number 328
Langley AFB, Virginia 23665-2107
(757)764-1046
An announcement of an availability session, the comment period, and the availability of the
Administrative Record for the remedy for OU-50 was published in the Daily Press, a newspaper
of general circulation in Hampton, VA, on November 29, 1998.
The public comment period for the Proposed Plan was from November 30, 1998 to December
29, 1998. A public availability session was held at the Virginia Air and Space Center in
Hampton, Virginia on December 3, 1998 to inform the public of the remedial alternatives and to
seek public comments. At this meeting, representatives from EPA, VDEQ, and the Air Force
were available to answer questions about conditions at the OU and the remedial alternative under
consideration. Responses to the comments received during this period are included in the
Responsiveness Summary section of this Record of Decision (ROD).
This ROD presents the selected remedial action for OU-50 determined in accordance with
CERCLA, and to the extent practicable, the NCP. All documents considered or relied upon in
reaching the remedy selection decision contained in this ROD are included in the Administrative
Record for the Site and can be reviewed at the information repositories.
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IV. SCQPe and Rote of Operable Ugft
Langley AFB was proposed to be included on the NPL in 1993 and finalized in 1994. The NPL
includes Sites where uncontrolled hazardous substance releases may potentially present serious
threats to human health and the environment. Discrete portions of an NPL site are often
managed more effectively as Operable Units. OU-50 is one of the IRP OUs currently being
investigated under CERCLA at Langley AFB. This ROD addresses OU-50, which is the IRP
Site 61 soil and ground water. The remaining OUs at Langley AFB are currently being
independently investigated under CERCLA (Table 1).
V. Summary of OU Characteristics and Extent of Contamination
Summarized below are the relevant findings of the work to date with regard to contaminated
media (soil, ground water, surface water and sediment) located within the boundaries of the OU.
A. OU Characteristics
1. Geology
The OU lies within the Atlantic Coastal Plain physiographic province. Ground surface at
Langley AFB is predominantly flat lying, with most of the Base lying between 5 and 8 feet
above mean sea level (msl). Drainage in the region is poor, with numerous saltwater and
freshwater marshes located along the major streams flowing into the Chesapeake Bay. OU-50 is
on the Southwest Branch of the Back River.
The geology of the area around Langley AFB consists of a thin layer of topsoil overlying fill
materials of varying thickness placed in developed areas and unconsolidated coastal plain
sediments.1 Topsoil is primarily sandy, silty clays or silty, clayey sands deposited within the
flood plains during periods of higher sea level stands or deposited in an estuarine or lagoonal
environment. Fill material includes gravel, rubble, and construction debris, and is similar to
native materials. The coastal plain sediments were deposited when the area was a submerged
near-shore marine environment.
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2. Hydrogeology
Three major ground water-bearing zones lie beneath Langley AFB. These include the Shallow
Water Table Aquifer between 5 and 100 feet bgs, the Upper Artesian Aquifer between 100 and
400 feet bgs, and the Principal Artesian Aquifer between 400 and 700 feet bgs. Recently
measured ground water elevations at OU-50 ranged from 2.2 to 4.3 feet above msl. Even
though the ground water in the vicinity of Langley AFB, including OU-50, is not used as a
source of drinking water, individual homeowners have ground water wells that have been used
for watering lawns and washing cars. However, the Shallow Water Table Aquifer provides an
important source of drinking water farther to the west in King Williams, Charles City, New
Kent, James City, and York Counties. In Newport News and Hampton, there are areas where
domestic ground water is obtained from wells that range from 50 to 100 feet in depth. These
wells are probably completed in the Shallow Water Table Aquifer, which ranges from 5 to 100
feet below land surface.2 Ground water in the shallow water table aquifer beneath the Base is not
used as a source of drinking water due to high dissolved solids levels and low aquifer yield.
Ground water flow in this aquifer is slow and flow direction is towards surface water bodies,
including the Back River and its tributaries.
3. Meteorology
Langley AFB has a modified continental-type climate with mild winters.1 During both winter
and summer, temperatures are fairly moderate,-with winter temperatures ranging from 40 to 70
degrees Fahrenheit (°F), and summer temperatures ranging from lows of 70°F to highs of mid-
80s °F. Relative humidity varies between 67 and 76 percent, depending on the month.
Prevailing wind direction is from the north during winter and from the south-southwest during
the rest of the year. Precipitation ranges from 24 to 57 inches per year, and is evenly distributed
throughout the year. Maximum precipitation is in July and August, with minimums in
November and April. Average seasonal snowfall in the area is less than 10 inches per year.
4. Ecology
OU-50 lacks vegetation and is composed of structures, pavement, gravel and concrete slabs.
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5. Soils
Soil at OU-50 has generally been paved with 90 percent of the ground surface covered by either
asphalt or Building 615. OU-50 is known to be partially underlain by "made land", or fill
materials of unknown origin.
B. Nature and Extent of Contamination
In June of 1998 a Remedial Investigation (RI) was completed for OU-50. The following is a
summary of the RI.5
Ground Water
As a result of activities at OU-50, a plume of benzene in ground water is present. The
plume size is limited in lateral extent, has decreased in size over time, is centered at
monitoring well SS61-MW2, and has not migrated beyond the boundaries of the OU.
Arsenic levels exceed the USEPA Region HI tap water risk-based concentration (RBC).
The highest concentrations of this inorganic chemical were observed in the northeastern
portion of OU-50 (see Table 2, Appendix A).
Other contaminants detected in ground water at OU-50 above USEPA tap water RBCs
or pertinent regulatory levels include volatile organic compounds (acetone, carbon
disulfide, chloroform, chloromethane, ethylbenzene and toluene); semi-volatile organic
compounds (carbazole and naphthalene, the pesticide dieldrin, PCB-1260); and metals
(barium, iron, manganese and thallium) (see Table 2, Appendix A).
Soils
Benzo(a)pyrene, a semi-volatile organic compound, was detected in surface soils across
OU-50. Concentrations in four samples exceeded USEPA's industrial RBC. The
widespread presence of this compound may be attributed to the non-native materials and
dredge spoils used to fill OU-50 (see Table 3, Appendix A).
Arsenic was detected in 18 soil samples, 15 of which exceeded USEPA's industrial
RBC. In general, concentrations increased east to west across OU-50, and
concentrations were generally greater in the subsurface soils than in the surface soils
(see Table 3, Appendix A).
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PCB-1260 was detected in surface and subsurface soils in the eastern half of OU-50.
Only the easternmost samples exceeded USEPA's industrial RBCs (see Table 3,
Appendix A), The limited occurrence of PCB in soils may be related to the presence of
non-native fill materials or the result of historical activities at adjacent OU-48 (Site OT-
55).
Lead was detected in all 18 soil samples collected, but only two exceeded USEPA's
residential screening level (there is no current industrial screening level for lead) (see
Table 3, Appendix A).
Surface Water and Sediment
Estimated surface water and sediment concentrations for those contaminants of concern
detected in the ground water do not pose a risk to aquatic receptors.
Contaminant Fate and Transport
OU-50 is located adjacent to the Base Marina, which represents an active potential source for
contamination of sediments and surface water. Therefore, modeling techniques, rather than
sampling, were used to evaluate the potential impacts associated with the discharge of
contaminated ground water from OU-50 to the Back River. Based on the results of the model
results, no impacts to surface water/sediment are likely to be associated with ground water
discharge from OU-50.
VI. Current and Potential Future OU and Resource Uses
Current land use at OU-50 is classified as industrial and future land use is expected to remain
industrial with the exception of incorporating the waterfront development plans. Details of the
Waterfront Development Plans follow.
Waterfront Development Plans
A 10 year shoreline restoration plan has been created to guide the wetlands and shoreline
stabilization projects for a mile of shoreline on LAFB between the marina and the end of the
mile long building. For the area immediately to the east of the existing marina which includes
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OU-50 (Figure 4), the design has called for the following:
Shoreline Stabilization Improvements
- Recycling and resizing existing miss-sized hardscape materials
- Removal of unsuitable materials
- Proper installation of Filter Cloth
- Reshaping of shore and installation of Class I rip rap
- Planting of wetland fringe marsh
Planting Riparian Forest Buffer
- Native shrub and tree plantings between shoreline stabilization and parking lot
- Buffer acts as filtration feature
Improvement of Pedestrian linkages along the waterfront
- Pedestrian pathway winds through the native plantings
- Paving will be pervious paver material or paver block material
Improving Parking
- Resurface, restripe and efficiently align parking spaces as shown on the waterfront
plans to accommodate additional parking spaces
- Area along the bulkhead at the gas pumps will remain covered with hardscape
material to ensure the exposure pathway from the surface of the hardscape material to
the soils beneath remains incomplete
Fish Cleaning Station
- Existing station will be replaced with new fish cleaning equipment
There are currently no restrictions regarding use at OU-50, such as fences and signs. Land
adjacent to OU-50 is currently industrial, recreational and commercial. Future adjacent land use
is expected to remain the same.
Ground water in the shallow water table aquifer at Langley AFB is not currently used as a source
of drinking water at or within Vi mile of the Base.3 Ground water near the coast is brackish to
saline, and therefore not potable.
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VII. Summar of QU
A risk assessment was conducted during the RI in accordance with the latest EPA policy on risk
assessments.6 The results are summarized below.5
A. Human Health Risk Assessment
The baseline risk assessment provides the basis for taking action and indicates the exposure
pathways that need to be addressed by this remedial action. It serves as the baseline indicating
what risks could exist if no action was taken at OU-50. This section of the ROD reports the
results of the baseline risk assessment conducted for this OU.
Health risks are based on a conservative estimate of the potential carcinogenic risk or the
potential to cause other health effects not related to cancer. Carcinogenic risks and
noncarcinogenic risks were evaluated. Three factors were considered:
Nature and extent of contaminants at OU-50
Pathways through which human and ecological receptors are or may be exposed to
those contaminants at OU-50
Potential toxic effects of those contaminants.
For this OU, the human health risk assessment was based on exposure to soil under industrial
land use scenarios and exposure to groundwater under the potential future residential receptor as
a conservative estimate in the unlikely event that OU-50 might be developed for residential use.
The industrial land use was assumed to be exposure through construction activities limited to ten
days a year. Exposure would result from construction activities that require exposure to soils
beneath the current asphalt cover. Surface water and sediment exposure as a result of marina
activities was considered in a qualitative manner.
Cancer risks are expressed as numbers reflecting the increased chance that a person will develop
cancer, if he/she is directly exposed (i.e., through working at the OU) to the contaminants found
in the ground water and soil at the OU over a period of time. For example, EPA's acceptable risk
range for Superfund OUs is 1 * 10"* to 1 * 10"*, meaning there is one additional chance in ten
thousand (1 * 10"4) to one additional chance in one million (1 * 10"6) that a person will develop
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cancer if exposed to contaminants at a Superfund OU. The risk associated with developing other
health effects is expressed as a hazard index (HI), which is the ratio of the existing level of
exposure to contaminants at a OU to an acceptable level of exposure. Below an HI of 1, adverse
effects are not expected.
The human health risk assessment evaluated the results of:
Direct contact with the contaminated soil
Incidental ingestion of contaminated soil
Inhalation of fugitive dust
Ingestion of contaminated ground water
Inhalation of vapor phase chemicals via ground water use
Dermal contact with contaminated ground water
Concentrations of chemicals detected in the soil, ground water, sediment and surface water
during the focused RI were compared to risk-based screening levels and background levels. The
chemicals of potential concern (COPC) identified in soil at OU-50 were metals (arsenic) and
volatile and semi-volatile organic (benzo(a)pyrene) compounds and PCB-1260. COPCs
identified in groundwater were acetone, arsenic, barium, benzene, carbazole, carbon disulfide,
chloroform, chloromethane, dieldrin, ethylbenzene, iron, manganese, napthalene, PCB-1260,
toluene and thallium. The COPCs for soil and groundwater were then evaluated in the human
health risk assessment. Estimated sediment and surface water concentrations were compared to
RBCs. No exceedences were identified, concluding that a risk assessment for exposure to these
media was unnecessary.
Health risk levels, determined using EPA guidance to ensure that conservative estimates of
potential health effects are determined, differ depending on the assumed land use because human
exposures differ with land use. A conservative estimate of risk was developed incorporating the
potential exposure pathways including direct skin contact with contaminated soil and ground
water, accidental ingestion of soil and ground water, and inhalation of contaminated soil
particles and ground water. Plausible receptors that may be exposed to soil at the OU and which
were evaluated in the risk assessment included a construction worker, and future adult and child
resident (ground water only).
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The lifetime cancer risk from exposure to contaminated soil for the construction worker at OU-
50 is calculated as 4.3 x 1CT*. This lifetime risk is within the EPA's acceptable risk range of 1 x
10"* to 1 x 10"4. The HI for the non-carcinogenic risk due to exposure to contaminated soil for
the construction worker was estimated to be 0.012, which is below the target level of 1.0.
For a theoretical future residential user, ground water use risk was determined to be 7 x 10"3,
which exceeds EPA's acceptable risk range. The calculated HI for the adult ground water
consumer is 123 and for the child, 131, levels at which adverse health effects may occur.
B. Ecological Risk Assessment
OU-50 lacks vegetation and is composed of structures, pavement, gravel and concrete slabs. As
a result, no complete exposure pathways for ecological receptors are associated with OU-50
soils, and potential ecological risks associated with exposure to soil constituents were not
quantified.
The only potential exposure pathway to which ecological receptors could be exposed is the
discharge of ground water to the Back River. Potential risks to ecological receptors were
quantified for this pathway through the development of environmental effects quotients (EEQs).
EEQs for ecological risk are similar to the hazard indices prepared for human health risk. They
are determined by dividing the site-specific concentrations by a conservative screening level.
The results of the EEQ calculations indicated that none of the constituents for which surface
water and sediment concentrations were estimated had calculated EEQs greater than 1. These
results indicate that estimated surface water and sediment concentrations in the Back River do
not represent levels of concern from an ecological standpoint with respect to direct contact (i.e.,
ingestion via gills and ingestion of sediment).
C. Conclusions
The remedial objective for OU-50 is to protect human health and the environment. Because the
current and anticipated future land use is non-residential, soils were evaluated only for
construction worker exposure. As indicated, the risk posed to the construction worker is within
EPA's acceptable risk range; however, actual or threatened releases from hazardous substances
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may present an imminent and substantial endangerment to public health or welfare under a non-
industrial scenario. In addition, the risk from ground water to the theoretical resident exceeds
EPA's acceptable risk range. Ecological risk assessment determined that there is minimal risk to
terrestrial receptors at OU-50. The specific remedial objectives for this operable unit, therefore,
are to assure that non-industrial use of the property, with the exception of the non-industrial
waterfront development plans outlined in Section VI, and to prevent access to ground water
other than for monitoring purposes.
VIII. Description of Alternatives
The Feasibility Study for OU-50 presents five alternatives that address risks posed by
contaminated ground water and soils. A summary of the remedial alternatives evaluated for OU-
50 is presented below.
Alternative 1- No Action
The NCP requires that a "no action" alternative be considered to provide a baseline for
comparison with action alternatives. Under this alternative, no remedial action would be
undertaken to address contaminated soil and ground water at OU-50.
Capital Cost: $0
Operations and maintenance (O&M) cost: $0
Net present worth: $0
Alternative 2 - Limited Action and Institutional Controls
This alternative includes institutional controls: land use restrictions to limit future uses of the OU
and require permits, qualified supervision, and health and safety precautions for activities
conducted on and near the OU. Because soils were evaluated for worker exposure (and not a
residential receptor), the use of this property would be restricted to industrial use under this
alternative. Ground water was not evaluated for construction worker exposure. These
restrictions include: 1) land use restrictions to prevent non- industrial use of the property, with
the exception of the non-residential waterfront development plans outlined in Section VI, and to
maintain the integrity of the current asphalt parking lot; 2) ground water use restrictions to
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prohibit the use of ground water for purposes other than monitoring; 3) within 90 days of ROD
signature, the Air Force shall produce a survey plat prepared by a professional land surveyor
registered by the Commonwealth of Virginia indicating the location and dimensions of OU-50
and the extent of soil and ground water contamination; and; 4) the Air Force shall incorporate
these restrictions and supply a copy of the plat into any real property documents necessary for
transferring ownership from the United States, in the unlikely event that the United States sells
or transfers the property. The real property document would also include a discussion of the
National Priorities List (NPL) status of this OU, as well as a description of the soil and ground
water contamination.- The Air Force shall submit the survey plat to the City of Hampton
recording authority for the limited purpose of providing public notice of the environmental
conditions of and limitations on the use of the property. No property right or interest is intended
to be nor shall be created by such notice. In addition, the Air Force shall enter a note, in the
local land recording office, to the real property document evidencing U.S. ownership of the
property on which the OU is located that shall notify interested parties that the site was
previously used to manage paint shop substances and waste.
In addition, public awareness training would be developed and implemented to keep potentially
affected individuals aware of possible hazards at the OU. Planning for emergency procedures
would also be developed to deal with accidental exposures or sudden risk increases in affected
areas.
Capital Cost: $27,000
Operations and maintenance (O&M) cost: $14,000
Net present worth: $242,000
Alternative 3 - Monitoring and Institutional Controls
This alternative contains all the provisions of Alternative 2, Limited Action and Institutional
Controls, plus ground water monitoring at OU-50. Samples would be collected from monitoring
wells and would be analyzed for the risk drivers and any other contaminants of concern or -
parameters deemed necessary.
13
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The frequency and duration of sampling will be determined in a subsequent remedial design.
Capital Cost: $27,000
Operations and maintenance (O&M) cost: $24,000
Net present worth: $396,000
Alternative 4 - Ground Water Extraction/GMF/Air Stripping/Discharge tn Surface Water an
Institutional C
This alternative includes ground water extraction through an extraction well or recovery trench
system. Extracted ground water will pass through a granular media filtration (GMF) system to
remove suspended solids. Filtered water will be treated in a low-profile air stripper to remove
the volatile organic compounds. Treated ground water would be discharged to the Back River.
Sludges resulting from the filtration system would be characterized and properly disposed. This
alternative would also require future institutional controls. Ground water use restrictions would
be implemented until completion of the remedy.
Capital Cost: $325,000
Operations and maintenance (O&M) cost: $71,200
Net present worth: $1,419,200
Alternative $ - Ground Water Extraction/Chemical Precipitatinn/Air Stripping/Discharge to
Surface Water and Institutional Controls
This alternative is identical to Alternative 4, except that a chemical precipitation process
(vertical sludge blanket clarifier) would be used to remove metals and suspended solids. Since
chemicals must be added to the extracted ground water, a step would be added to the treatment
process to mix the chemicals and ground water to form a slurry. This alternative would also
require future institutional controls. Ground water use restrictions would be implemented until
completion of the remedy.
Capital Cost: $325,200
Annual O&M Cost: $84,400
Present Worth: $1,622,200
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IX. Summary of Comparative Analysis of Alternatives
During the detailed evaluation of remedial alternatives, each alternative is assessed against the
following nine evaluation criteria: overall protection of human health and the environment;
compliance with applicable and relevant and appropriate requirements (ARARs); long-term
effectiveness and permanence; reduction of toxicity, mobility and/or volume (TMV); short-term
effectiveness; implementability; cost; state acceptance; and community acceptance.
A comparative analysis for the five alternatives based on these evaluation criteria is presented in
the following sections.
A. Overall Protection of Human Health and the Environment
Under Alternative 1, no remedial action would be implemented. The current site conditions and
property use present no risk to human health because ground water is not used and constituents
in soils do not pose an unacceptable risk under the industrial use scenario. This alternative,
however, is not protective of an unrestricted use scenario. Furthermore, since soils were
evaluated only for industrial use scenarios, there may be potential risk under different types of
scenarios. Under Alternatives 2 and 3, institutional controls would be implemented. The
enforcement of the institutional controls, specifically the requirement for industrial use only and
the prohibition of contact with, and consumption of, ground water would eliminate exposure
pathways that could present significant risk to future users. The institutional controls would
mitigate both the carcinogenic and non-carcinogenic risks described in Section VII. Alternatives
4 and 5 protect both human health and the environment through treatment of contaminated
ground water thereby controlling the mobility of contaminants and reducing contaminant
concentrations. Ground water use restrictions would be implemented until treatment of the
ground water is complete. Also, institutional controls would prohibit use of the property for
purposes other than industrial. These alternatives would be protective of human health and the
environment under current and future use scenarios. No significant risk to terrestrial or aquatic
life was identified for OU-50 due to both a lack of sustainable habitat and insignificant levels of
bioaccumulating contaminants.
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B. Compliance with ARARs
Since this ROD involves an interim measure with respect to ground water contamination, final
remediation goals and hence, ARARs, are not identified here. This ROD, however, does present
a final action for soils. The soils under all five alternatives would be in compliance with all
ARARs. (Specific ARARs for the remedy in this case are identified in Section XI of this ROD).
C. Long-term Effectiveness and Permanence
Implementation of Alternative 1 could be effective and permanent in the long-term if considering
soil alone because no significant contamination is present, assuming continued industrial use.
However, in the long-term, individuals could be exposed to contamination through contact with
ground water, and the property could be used for nonindustrial purposes, possibly increasing the
risk to human health. Therefore, Alternative 1 does not meet the requirements for long-term
effectiveness and permanence.
For Alternatives 2 and 3 The long-term effectiveness of the institutional controls will be
contingent upon enforcement of the use restrictions by the Air Force through the Land Use
Control Assurance Plan (LUCAP) as described in Section X. Implementation of Alternatives 2
and 3 would maintain the industrial use of OU-50 and reduce the risk the future risk of exposure
to ground water by the development and enforcement of restrictions. Because these restrictions
would become a permanent part of the real estate documentation, through the submittal of the
survey plat as described in Section X, and because the restrictions would be required to be
included in any sales, transfers and/or lease agreements, this alternative would be a long-term
and permanent remedial action.
In addition to land use and ground water use restrictions described in Alternatives 2 and 3,
Alternatives 4 and 5 include technologies that provide effective, permanent removal of
contaminants from OU-50. Alternatives 4 and 5 include a system of pumping wells for ground
water extraction. The effectiveness of the extraction system can be evaluated based on pump
tests conducted in the proposed location. The effectiveness of these alternatives can be
evaluated through monitoring of the system performance.
16
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Alternative 4 includes GMF, an effective technology for the removal of suspended material and
associated inorganic contaminants from the extracted ground water. Metals are removed less
effectively unless some form of pretreatment is utilized. Solids removed in this process must be
dewatered and disposed. These solids are not expected to be hazardous because of the low metal
concentrations found in the ground water, but testing would be necessary to properly
characterize the solids for disposal.
Alternative 5 includes chemical precipitation, an effective technology for removal of metals and
suspended solids. This process would be more effective than GMF if low metals concentrations
are required for discharge to surface water or if metals could cause fouling of the air stripper.
Precipitates generated in this process would require characterization prior to disposal, but
because metals present in OU-50 are at relatively low levels, the residuals are not expected to be
hazardous.
Alternatives 4 and 5 propose an air stripping process for removal of organics in the ground
water. The effectiveness of this process is dependent on influent VOC concentrations, air-water
ratio, and proper design and sizing of the stripper. This technology does not destroy the VOC
compounds but rather eliminates them from the water stream.
Alternatives 4 and 5 are expected to provide long-term effectiveness and permanence under both
current and future use scenarios.
D. Reduction of Toxicity, Mobility, or Volume through Treatment
The No Action, Limited Action, and Monitoring alternatives (Alternatives 1, 2 and 3) would not
reduce the toxicity, mobility, or volume of contaminants at the OU since the alternatives do not
involve physical remedial actions. Because ground water contamination is being addressed as a
separate OU, the statutory preference for remedies that employ treatment that reduces the
toxicity, mobility, and/or volume a s a principle element will be addressed by the final ground
water response.
Alternatives 4 and 5 would reduce toxicity, mobility, and volume of contamination at Site 61.
Toxicity would be reduced by removal of organic and inorganic contaminants by the various
treatment processes. Mobility would be reduced through extracting contaminated ground water
17
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in Alternatives 4 and 5, thereby controlling the rate and extent of migration. Volume would be
reduced through the removal and/or destruction of contaminants in ground water.
E. Short-term Effectiveness
No impact to short-term effectiveness would be expected from the No Action, Limited Action, or
Monitoring alternatives, Alternatives 1, 2, and 3, respectively.
Conventional construction equipment would be used to complete the ground water extraction
system, treatment facilities, and outfall system in Alternatives 4 and 5; site workers would not
face risks beyond those inherent in any construction project. Langley AFB employees and
surrounding residents would be unaffected by construction activities.
Design and construction of the remediation systems will require approximately 12-24 months,
including detailed design and review, bid package preparation, contractor and equipment
supplier selection, construction and installation of equipment, and start-up and shakedown.
Under the RAGS Part C, the risks associated with the operation of an on-site air stripper should
be considered short-term risks. Although the operation may occur over a period of many years,
exposure to emissions is viewed as a short-term risk. The site and access restrictions that are
included as part of this alternative will control and limit any potential exposure from the air
stripper emissions in Alternatives 4 and 5.
F. Implementability
The unit processes assembled hi Alternatives 4 and 5 are all commonly used in water treatment
and are commercially available. Electricity and a potable water supply are the only necessary
utilities and are currently available at the OU.
The No Action alternative would be the easiest to implement followed by the Limited Action
alternative and the Monitoring alternative (Alternatives 1, 2, and 3).
Alternative 4 would be the next easiest to implement but still will not require any extraordinary
effort since all treatment technologies are common and readily available. The chemical
18
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precipitation process makes Alternative 5 less desirable than Alternative 4 unless lower metal
, discharge limits are needed than can be achieved by GMF.
The proposed discharge system, common to Alternatives 4 and 5, is implementable. However,
coordination with VDEQ would be required to determine the effluent discharge limits to the
Back River.
Administrative oversight would be necessary for all alternatives to ensure proper operation and
maintenance of the chosen alternative. Monitoring of effluent contaminant concentrations, flow
rates, residual testing, and effectiveness evaluations would be required for Alternatives 4 and 5.
Duties associated with performing, coordinating, and managing these tasks are feasible and
implementable.
G. Cost
Estimated costs for the alternatives are summarized in Section VIE. These are preliminary
estimates and are subject to change as the alternatives are refined (through pilot tests, etc.).
The No Action alternative (Alternative 1) has no cost and the Limited Action alternative
(Alternative 2) only a minimal cost consideration. The Monitoring alternative (Alternative 3) is
the next least expensive alternative followed by Alternatives 4 and 5, respectively.
Competitive bidding and/or vendor discounts may significantly reduce capital costs for the unit
processes.
O&M costs for the other alternatives is also uncertain since influent concentrations, both organic
and inorganic, are not defined at this time.
H. State Acceptance
The Virginia Department of Environmental Quality concurs with the selection of Alternative 3,
Monitoring and Institutional Controls as the selected remedy for this OU.
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I. Community Acceptance
A public meeting on the Proposed Plan, which described Alternative 3 as the preferred
alternative, was held on December 3, 1998 in Hampton, Virginia. Comments received orally
and/or in writing at the availability session are referenced in the Responsiveness Summary
(Section XIH of this ROD).
X. Selected Remedy
Following review and consideration of the information in the Administrative Record file,
requirements of CERCLA and the NCP, and the review of public comments on the Proposed
Remedial Action Plan, the Air Force and EPA, in consultation with VDEQ, have selected
Alternative 3: Monitoring and Institutional Controls as the remedy for OU-50. This remedy will
prevent unacceptable exposure to soil and groundwater. The total present worth costs of the
selected remedy are estimated at $396,000.00
Based on available information, the Air Force and EPA believe that the selected remedy would
be protective of human health and the environment, would be cost-effective, and would provide
the best balance of trade-offs among the alternatives with respect to the evaluation criteria.
The selected remedy for OU-50 includes the following major components:
1) Land use restrictions to prevent non-industrial use of the property, with the exception of
the non-residential waterfront development plans discussed in Section VI and to
maintain the integrity of the current asphalt parking lot;;
2) Ground water use restrictions to prohibit use of the ground water for purposes
other than monitoring;
3) Within 90 days of ROD signature, the Air Force shall produce a survey plat prepared by
a professional land surveyor registered by the Commonwealth of Virginia indicating the
location and dimensions of OU-50 and the extent of soil and ground water
contamination;
4) The Air Force shall supply a copy of the plat and ensure incorporation of these
restrictions into any real property documents necessary for transferring ownership from
the United States, in the unlikely event that the United States sells or transfers the
20
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property. The real property document would also include a discussion of the National
Priorities List (NPL) status of this Site, as well as a description of the soil and ground
water contamination. The precise boundaries of the areas in which residential use is
prohibited shall be fixed during the development of the Land Use Control
Implementation Plan described later in this section. The Air Force shall submit the
survey plat to the City of Hampton recording authority for the limited purpose of
providing public notice of the environmental conditions of and limitations on the use of
the property. No property right or interest is intended to be nor shall be created by such
notice. In addition, the Air Force shall enter a note, in the local land recording office, to
the real property document evidencing U.S. ownership of the property on which the OU
is located that shall notify interested parties that the site was previously used to manage
paint shop substances and waste;
5) Ground water monitoring to ensure contaminated ground water is not impacting the
Back River, but this is not the final remedy for ground water. Ground water will be
addressed in a final action on an installation-wide basis as a separate OU. Specifics of
the monitoring program will be developed by the Air Force, the United States
Environmental Protection Agency and the Virginia Department of Environmental
Quality and presented in a monitoring plan.
Within 90 days of the execution of this ROD, the LAFB shall develop a Land Use Control
Implementation Plan (LUCIP) for OU-50 with the concurrence of EPA Region m and in
consultation with the Commonwealth of Virginia. The LUCIP shall include:
(1) a description and the location of OU-50, including a map, a description of the OU's
approximate size and a description of the COCs;
(2) the land use control objectives (LUCs) selected above;
(3) the particular controls and mechanisms to achieve these goals;
(4) a reference to this ROD; and;
(5) any other pertinent information.
Within 180 days following the execution of this ROD, the Air Force, with the concurrence of
EPA Region ffl and in consultation with the Commonwealth of Virginia, shall develop a
Memorandum of Agreement on Land Use Control (MOALUC) for LAFB. The MOALUC shall
contain Base-wide periodic inspection, condition certification and agency notification
21
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procedures designed to ensure the maintenance by LAFB personnel of any site specific LUCs
deemed necessary for future protection of human health and the environment, including LUCs
selected in this ROD. A fundamental premise underlying execution of the MOALUC is that,
through the Air Force's substantial good-faith compliance with procedures called for therein,
reasonable assurances will be provided to USEPA and the Commonwealth of Virginia as to the
permanency of those remedies which include the use of specific LUCs.
Although the terms and conditions of the MOALUC will not be specifically incorporated or
made enforceable as to this or any other ROD, it is understood and agreed by the Air Force,
USEPA and the Commonwealth of Virginia that the contemplated permanence of the remedy
reflected herein shall be dependent upon LAFB's good-faith compliance with the MOALUC.
Should such compliance not occur or should the MOALUC be terminated it is understood that
the protectiveness of the remedy concurred in may be reconsidered and that additional measures
may need to be taken to ensure necessary future protection of human health and the environment.
XI. Statutory Determinations
Under CERCLA Section 121, EPA must select remedies that are protective of human health and
the environment, comply with applicable or relevant and appropriate requirements (unless a
statutory waiver is justified), are cost-effective, and utilize permanent solutions and alternative
treatment technologies or resource recovery technologies to the maximum extent practicable. In
addition, CERCLA includes a preference for remedies that employ treatment that permanently
and significantly reduce the volume, toxicity, or mobility of hazardous waste as their principle
element. The following sections discuss the remedy in light of these statutory requirements.
A. Protection of Human Health and the Environment
The selected remedy, Alternative 3, would protect human health and the environment. The
institutional controls will mitigate both the carcinogenic and non-carcinogenic risk described in
Section VII.
B. Compliance with ARARs
Since the remedy regarding ground water is an interim measure, final cleanup objectives and
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ARARs will be addressed in a subsequent basewide ground water ROD. This ROD, however
does present a final action for soils. The selected remedy will comply with all ARARs (there are
no chemical-, location-, or action- specific ARARs).
C. Cost Effectiveness
The selected remedy, Monitoring and Institutional Controls, was chosen because it provides the
best balance among criteria used to evaluate the alternatives considered in Section IX. The
alternative was found to achieve both adequate protection of human health and the environment
and to meet statutory requirements of Section 121 of CERCLA. The selected remedy was found
to be cost-effective. The cost of Alternative 3 has been established to be $396,000.00.
D. Utilization of Permanent Solutions and Alternate Treatment Technologies
or Resource Recovery Technologies to the Maximum Extent Practicable
The Air Force, EPA and VDEQ have determined that the selected remedy represents the
maximum extent to which permanent solutions and treatment technologies can be utilized in a
cost-effective manner for OU-50. The ground water portion of this action, however, is interim
and is not intended to utilize permanent solutions and alternative treatment (or resource
recovery) technologies to the maximum extent practicable.
E. Preference for Treatment as a Principle Element
The selected remedy for OU-50, Monitoring and Institutional Controls, does not satisfy the
statutory preference for treatment as a principal element of the remedy. With respect to the
soils, as long as the property is not used for non-industrial purposes, a treatment remedy is not
required. As for the ground water, since the selected action does not constitute a final remedy,
the statutory preference for remedies that employ treatment that reduces toxicity, mobility, or
volume as a principal element will be addressed by the final ground water response action.
XII. Significant Changes from Proposed P|ap
The proposed plan for OU-50 was released for public comment on November 30, 1998. The
proposed remedial alternative identified in the proposed plan was Monitoring and Institutional
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Controls. The Air Force, EPA and VDEQ reviewed and considered all comments received
during the public meeting and during the public comment period. Since the public comment
period ended, the Air Force has developed waterfront beautification plans which include
changes to the use of the waterfront property at OU-50, specifically, the inclusion of a walkway
along the shoreline. These plans are discussed in detail in Section VI. EPA independently
assessed the potential future recreational use of OU-50 and found that although the recreational
user would have a higher risk than a construction worker, neither a hazard index greater than 1
nor a cancer risk greater than 1 x 10*4 is expected.7-1 Therefore, the limitations of the institutional
controls, as presented in the Proposed Plan, have been slightly altered to allow for walkway
installation.
XIII. Responsiveness Summary
A. Overview
In a proposed plan released for public comment on November 29, 1998, Langley AFB, with the
support of EPA and VDEQ, identified Monitoring and Institutional Controls as the preferred
remedial alternative for OU-50.* There were no written comments received as a result of the
public comment period. There were no written comments submitted during the December 3,
1998 availability session held in Hampton, Virginia. There were four questions presented orally
at the availability session concerning OU-50. After evaluating and addressing these comments,
Langley AFB and EPA, with the support of VDEQ, have selected Monitoring and Institutional
Controls as the remedy for OU-50. Comments and the associated responses of Langley AFB,
EPA, and VDEQ are described below after a brief discussion of community involvement to date.
B. Community Involvement to Date
The Langley AFB Partnership established a public comment period from November 29, 1998 to
December 29, 1998 for interested parties to comment on the proposed plan for OU-50. These and
all other documents considered or relied upon during the remedy selection process for OU-50 are
included in the Administrative Record, which has been established in two information
repositories accessible to the public since the beginning of the public comment period for OU-
50. An availability session was held at the Virginia Air and Space Center, Hampton, Virginia,
on December 3, 1998 to present the proposed plan, answer questions, and accept both oral and
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written comments on the OU-50 remedial alternative. Four persons attended this session.
This Responsiveness Summary, required by CERCLA, provides a summary of citizens'
comments received during the public meeting and the responses of the Air Force, EPA, and
VDEQ. Responses to these comments are included in the section below.
C. Summary of Comments Received During Public Comment Period and
Comment Responses
Comment #1:
Even though contamination has been found at the OU, the plan is only to monitor, not remove
anything from the OU? Will the contamination dissipate over time?
Response #1:
Yes, the groundwater contamination will dissipate over time and because there is no impact on
human health or the environment under the current land use, no removal is warranted.
Groundwater monitoring is important so that we can ensure that there is no future impact on the
Back River. Initially, more comprehensive monitoring would be conducted. After two quarters
of monitoring results are reviewed, some chemicals may fall out or a decision may be made to
monitor less frequently. If something shows up that is of potential concern then appropriate
steps would be taken. The ground water monitoring data also would be evaluated as part of the
five-year review. In addition, there is a base-wide ground water monitoring effort underway.
The Air Force, EPA and VDEQ, however, decided not to delay progress on this OU, allowing
this remedy to move forward apart from the base-wide effort.
Comment #2:
Who would be the contractor for this work?
Response #2:
For the ground water monitoring at OU-50 (Site OT-61) IT Corporation would do the work.
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Comment #3:
I was aware of the removal of an underground storage tank from this OU in the past, but I did not
know of the other aspects associated with remediation of the OU.
Response #3:
The underground storage tank was removed in 1993. The existing contamination is probably
associated with the paint shop operations that were conducted at the OU.
Comment #4:
Is there any natural attenuation involved too, or is just dissipation that will occur?
Response #4:
Both natural attenuation (where there is an actual breakdown of the chemicals) and dissipation
(where the contamination spreads out and is found in even lower concentrations) of the
groundwater will occur at the OU.
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X. References
^ersar, Inc., 1996, Langley Air Force Base Basewide Standard Operating Procedures:
Background Information Document, January 19.
2Radian Corporation, 1996, OU Inspection and Screening Risk Assessment Report for 33
Installation Restoration Program OUs, Draft, Langley Air Force Base, Virginia, February.
3Radian International, 1998, Final Installation Restoration Program (IRP) Conceptual
Hydrogeological Model Report for Langley Air Force Base, May.
4Langley Air Force Base, 1998, Final Proposed Plan for Remedial Action at Operable Unit 50,
Langley Air Force Base, Virginia, November.
5PMC, 1998, Final Remedial Investigation and Feasibility Report for IRP Site SS-61, Langley
Air Force Base, Virginia, 10 July.
6U.S. Environmental Protection Agency, 1989, Risk Assessment Guidance for Superfund,
Volume I: Human Health Evaluation Manual (Part A), Interim Final, Office of Emergency and
Remedial Response, Washington, DC, EPA/540/1-89/002.
7Driscoll, Stacie, 1999. Personal communication: Letter from Stacie Driscoll, U.S. EPA Region
III. 6 May.
8Driscoll, Stacie, 1999. Personal communication: Letter from Stacie Driscoll, U.S. EPA Region
in. 17 June.
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APPENDIX A
Tables
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Table 1
Summary of Operable Units Under CERCLA Investigation
Langley Air Force Base, Virginia
Pagel of 3
OU Name/IRP OU Name
Findings
Current Status
OU-21/LF-01
Former Landfill, End of 08/26
Runway
Contaminants of Potential
Concern (COPCs) - pesticides
and metals in the ground water
and soil.
In the remedial investigation (Rl) phase. A draft
Rl report has been submitted and reviewed. A
separate basewide ecological risk assessment
is currently underway.
OU-22/WP-02
Former Waste Water Treatment
Plant, Bldg 724
COPCs - pesticides and metals
in the ground water and soil.
In the Rl phase. A draft Rl report will be
submitted by mid-1999.
OU-23/LF-05
Former Landfill in the Shellbank
Area
COPCs - pesticides, volatile
organic compounds (VOCs),
and metals in the ground water;
pesticides and metals in the
surface water; and semivolatile
organic compounds (SVOCs)
and metals in the soil.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-24/OT-06
Former Entomology OU,
Shellbank Area
COPCs - pesticides, VOCs,
SVOC, and some metals in the
ground water; SVOCs,
pesticides and some metals in
the soil.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-25/LF-07
Former Landfill, Shellbank Area
COPCs - pesticides and some
metals in the ground water;
dieldrin in the soil.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-26/WP-08
Former Waste Water Treatment
Plant, Lighter Than Air (LTA) Area
COPCs - some pesticides and
metals in the ground water;
dieldrin in the soil.
In the Rl phase. A draft Rl report has been
submitted and reviewed.
OU-28/LF-10
Former Landfill, Golf Course
COPCs - VOCs, metals and
some pesticides in the ground
water VOCs and polychlorinated
biphenyte (PCBs) in surface
water; some metals in the soy.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
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OU Name/IRP OU Name
Findings
Current Status
OU-29. LF-11
Former Landfill, Tabbs Creek
Area
COPCs - VOCs, pesticides,
metals and PCBs in the ground
water; some metals in the
surface water; SVOCs, metals,
and PCBs in the soil.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-30/LF-12
Former Landfill, Munitions
Storage area, Northwest Area of
Base
COPCs - VOCs and metals in
the ground water; metals and 2,4
DB in the surface water; SVOCs
and nickel in the soil.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-31/LF-13
Former Landfill Munitions Storage
Area, Northwest Area of Base
COPCs - Aldrin, alpha-BHC and
some metals in the ground
water; VOCs, SVOCs, metals
and PCBs in the surface water.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-32/WP-14
Former Chemical Leach Pit,
Firing-ln Abutment Building 1303
COPCs - pesticides, SVOCs,
and some metals in the ground
water arsenic and dieldrin in the
soil.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-33/LF-15
Former Landfill, Willoughby Point
COPCs - VOCs, SVOCs,
pesticides and metals in the
ground water pesticides and
metals in the surface water.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-34/LF-17
Former Landfill, LTA Area
COPCs - VOCs, pesticides and
some metals in the ground
water; dieldrin and some metals
(mainly lead) in the soil.
In the Rl phase/ A draft Rl report will be
submitted by mid-1999.
OU-35/LF-18
Former Landfill, Northwest corner
of Base
COPCs - pesticides in the
ground water pesticides and
metals in the surface water
SVOCs and manganese in the
surface soil; detta-BHC, and
metals in the sediment
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-37/LF-22
Former LandfiB, Willoughby Point
OPCs - pesticides and metals
n the ground water alpha-BHC,
delta-BHC and metals in the
surface water.
In the Rl phase. A draft Rl report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
OU-40/OT-25
Old Entomology Building and
Former Storage Area, Bldg 965
OPCs - pesticides in the
ground water and soil.
n the Rl phase. A separate basewide
ecological risk assessment is currently
underway.
OU-42/OT-38A and B
Four Waste OH and Trash Burn
Areas, Basewide
Risk assessments showed no
significant risk to human health
or the environment from soite
The Record of Decision (ROD) for soils was
signed on January 14, 1999. Ground water
ROD wiy follow at a later date. The final Rl
report was submitted in September 1998.
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OU Name/IRP OU Name
OU-44/FT-41
Former Fire Training Area,
Firing-ln Abutment, Bldg 1303
OU-47/OT-51
Former Electrical Substation,
Shellbank Area, Bldg 82
OU-48/OT-55
Civil Engineering Yard,
Underground Petroleum
Contamination
OU-49/OT-56
Silver Contamination in Storm
Sewers, Basewide
OU-50/SS-61
Old Civil Engineering Paint
Shop/Marina
OU-51/SS-63
Back River Sediments
OU-52/OT-64
Ground water Contamination,
Basewide
Findings
COPCs - VOCs, pesticides,
dioxins, and some metals in the
ground water SVOCs, dioxins
and some metals in the surface
water.
COPCs - pesticides, PCBs and
lead in the soN.
COPCs - pesficides and dieldrin
in the ground water; pesticides
and PCBs in the soil.
COPCs - metals and VOCs in
surface water and metals,
SVOCs and pesticides in
sediment
COPCs - VOCs in the ground
water and soil.
COPCs - pesticides, metals, and
PCTs in the sediment
COPCs - pesticides and metals
n the ground water.
Current Status
In the Rl phase. A draft Rt report has been
submitted and reviewed. A separate basewide
ecological risk assessment is currently
underway.
The ROD for soil was signed on January 14,
1 999. Ground water ROD will follow at a later
date.
In the Rl phase. A draft Rl report is due to be
submitted by mid-1 999.
In the feasibility study (FS) phase. The FS is
due to be finalized by mid-1 999.
This OU is currently in the Record of Decision
Phase.
In the preliminary assessment/OU inspection
(PA/SI) phase. The draft PA/SI report is due to
be submitted by the end of 1 998
In the scoping phase. The long-term
monitoring project is due to be awarded by mid-
1999.
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Table 2
Maximum Groundwater Concentrations Exceeding Residential Tap water Levels
Page 1 of 1
Analyte
Acetone
Arsenic
Barium
Benzene
Carbazote
Carbon Disulfide
Chloroform
Chloromethane
Dieldrin
Ethylbenzene
Iron
Manganese
Napthalene
PCB-1260 (Arochlor 1260)
Thallium
Toluene
Value (ug/l)
440.00
252.00
1030.00
2400.00
7.00
130.00
2.00
54.00
0.0200
880.00
11700.00
2370.00
190.00
0.500
14.90
150.00
Screening Level (ug/l)
370.00
0.045
260.00
0.3600
3.400
100.00
0.1500
1.400
0.0042
130.00
1100.00
18.00
150.00
0.0087
0.290
75.00
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Table 3
Maximum Soil Concentrations Exceeding Industrial Screening Levels
Page 1 of 1
Analyte
Arsenic
Benzo(a)Pyrene
PCB-1260
Value (mg/kg)
17.30
4400.00
1200.00
Screening Level {mg/kg)
3.80
780.00
740.00
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APPENDIX B
Figures
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Goodwin Islands
Reference Location
20 Miles
BETHEL MANOR
OFF-BASE HOUSING
Figure 1. Location Map, Langley Air Force Base, Virginia
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Figure 2. Base Map of Ungley AFB Showing the Localion of the Slle
fSS-61/OU-sm
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Will remain
asphalt
Figure 4. Waterfront Development Plan
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APPENDIX C
Glossary
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Administrative Record: A collection of documents containing all the information and reports generated during the
entire phase of investigation and cleanup at the OU and used to make a decision on the selection of the preferred
alternative under CERCLA.
Carcinogenic Risk: Cancer risks are expressed as numbers reflecting the increased chance that a person will develop
cancer if exposed to chemicals or substances. For example, EPA's acceptable risk range for Superfund OUs is 1
x 10"4 to 1 x 10"6. This means that the probability of cancer should not be greater than 1 in 10,000 chance to a 1 in
1,000,000 chance above background.
Comprehensive Environmental Response, Compensation and Liability Act (CERCLA): A federal law,
commonly referred to as the Superfund Program, passed in 1980 that provides for the cleanup and emergency
response in connection with numerous existing inactive hazardous waste disposal OUs that endanger public health
and safety of the environment.
Chemicals of Potential of Concern (COPCs): Chemicals, either present at the OU as a result of historical activities
or of likely concern to human health and the environment, which are evaluated in the risk assessment.
Ecological Risk Assessment: An evaluation of the risk posed to the environment if remedial activities are not
performed at the OU.
Exposure Pathways: Describes the course a chemical or physical agent takes from the source to the exposed
individual. Elements of the exposure pathway are: (1) the source of the released chemical; (2) the contaminated
medium (e.g., soil); (3) a point of contact with the contaminated medium; and (4) an exposure route (e.g., ingestion,
inhalation) at a contact point.
Hazard Index (HI): A number indicative of non-carcinogenic health effects which is the ratio of the existing level of
exposure to an acceptable level of exposure. A value equal to or less than one indicates that the human population is
not likely to experience adverse effects.
Human Health Risk Assessment: An evaluation of the risk posed to human health should remedial activities not be
implemented.
Installation Restoration Program (IRP): Program established by the United States Air Force to systematically
identify and remediate contaminated OUs. The IRP was designed to be consistent with EPA rules and guidelines.
Lowest-Observed-Adverse-Effect Level (LOAEL): The lowest exposure level at which there are statistically or
biologically significant increases in frequency or severity of adverse effects between the exposed population and its
appropriate control group.
No-Observed-Adverse-Effect Level (NOAEL): An exposure level at which there are no statistically or biologically
significant increases in the frequency or severity of adverse effects between the exposed population and its appropri-
ate control; some effects may be produced at this level, but they are not considered as adverse, nor as precursors to
adverse effects. In any experiment with several NOAELs, the regulatory focus is primarily on the highest one,
leading to the common usage of the term NOAEL as the highest exposure without adverse effect.
Operable Unit (OU): A discrete portion of a OU or a discrete action representing an incremental step in the
investigation and remediation of hazardous substances at a facility.
Proposed Plan: A document that presents a proposed cleanup alternative and requests public input regarding the
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proposed alternative.
Record of Decision (ROD): A legal document that describes the cleanup action or remedy selected for a OU, the
basis for the choice of that remedy, and public comment on alternative remedies.
Remedial Action: Implementation of plans and specifications, developed as part of the design, to remediate a OU.
Remedial Investigation (RI): Part of a study of a facility that supports the selection of a remedy for a OU where
hazardous substances have been disposed. The RI identifies the nature and extent of contamination at the facility.
OU: The facility and any other areas in close proximity to the facility where a hazardous substance, hazardous waste
hazardous constituent, pollutant, or contaminant from the facility has been deposited, stored, disposed of, or placed or
has migrated or otherwise come to be located.
OU Inspection (SI): The SI determines if the OU presents an immediate threat that requires prompt response action
because the OU may pose a threat to human health and/or the environment.
OU-Related Risk: Cancer and non-cancer risk estimates that are based on contaminants present in environmental
media due to OU-specific human activities at Langley AFB, but that exclude the contribution of background
contaminant concentrations.
Superfund Amendments and Reauthorization Act (SARA): An amendment to CERCLA enacted in 1986.
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Reproduced by NTIS
.
v. O O
0 £ O fl)
CO fl*-
4-J 0 CD
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