PB99-963915
EPA541-R99-051
1999
EPA Superfund
Record of Decision:
Langley Air Force Base
NASA Langley Center OU 2
Hampton, VA
9/2/1999
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RECORD OF DECISION
NASA LANGLEY RESEARCH CENTER
STRATTON SUBSTATION OU
August 1999
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RECORD OF DECISION
NASA LANGLEY RESEARCH CENTER
DECLARATION
SITE NAME AND LOCATION
NASA Langley Research Center (NASA LaRC)
Stratton Substation Operable Unit
Hampton, Virginia
STATEMENT OF BASIS AND PURPOSE
^ *SS! °f De?isi°n (ROD> Presents *»» *!«** remedial action for the Stratton Substation Operable Unit (OU)
at the NASA Langley Research Center (LaRC) in Hampton, Virginia (the "Site"), chosen in accordance with the
comprehensive Envjronmental Response, Compensation, and Liability Act (CERCLA) of 1980 as amended, 42
U.S.C. §9601 sLsgg. and, to the extent practicable, the National Oil and Hazardous Substances Pollution
Conungency Plan (NCP), 40 C.F.R. Part 300. This decision is based on the Administrative Record for this Site.
The Virginia Department of Environmental Quality (VDEQ) concurs with the selected remedy.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this OU, if not addressed by implementing the response
actions selected in this ROD, may present an imminent and substantial endangerment to public health welfare or the
environment.
DESCRIPTION OF THE SELECTED REMEDY
The Stratton Substation OU cleanup is part of a comprehensive environmental investigation and cleanup currently
being performed at the NASA LaRC under the CERCLA program. This ROD addresses only the Stratton Substation
OU; the other OUs located at NASA LaRC will be addressed in future RODs. Also, this ROD addresses only soil at
the OU. The groundwater is being addressed as a separate OU and will be addressed in a future ROD.
This action addresses the principle threat at the Stratton Substation OU by excavating and disposing of contaminated
soil off-site and by imposing land use restrictions that will prevent any non-industrial activities to take place on the
The selected remedy is the excavation and off-site disposal of contaminated soil and the implementation of
institutional controls, which include:
1) excavation of soils with PCB concentrations greater than 10 parts per million (ppm), estimated at 212
cubic yards;
2) transporting and disposing of the soils off-site to a Toxics Substances Control Act (TSCA) - approved
chemical waste landfill;
3) backfilling excavated areas with clean fill material;
4) the prohibition of use of the property for purposes other than industrial (e.g., residential, child care or
recreational use);
5) inputting these restrictions in the NASA LaRC Master Plan;
6) within 90 days of ROD signature, NASA shall produce a survey plat prepared by a professional land
surveyor registered by the Commonwealth of Virginia indicating the location and dimensions of the
Stratton Substation Operable Unit and the extent of the soil contamination. The plat shall contain a note,
prominently displayed, which states the owner's future obligation to restrict the land use of the property.
The plat shall be submitted to the local recording authority;
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7) NASA shall incorporate these restrictions and submit a copy of the plat into any real property
documents necessary for transferring ownership from NASA, in the unlikely event that NASA sells 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 contamination;
8) The NASA LaRC Environmental Engineering Office Head will certify to USEPA on an annual basis
that there have been no violations of these prohibitions. If a violation has occurred, a description of the
violation and corrective actions to be taken will be provided.
DECLARATION OF STATUTORY DETERMINATIONS
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 to the remedial action, and is cost-effective The
remedy utilizes permanent solutions and alternative treatment technologies to the maximum extent practicable for
this OU.
Because this remedy may result in hazardous substances remaining onsite, a review will be conducted every 5 years
after the commencement of the remedial action, to ensure that the remedy continues to provide adequate protection
of human health and the environment.
Dr. Jeremiah F. Creedon Date
Director
NASA Langley Research Center
Date
Director
Hazardous Site Cleanup Division
U.S. Environmental Protection Agency, Region III
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TABLE OF CONTENTS
SECTION
PAGE
I. SITE NAME, LOCATION AND DESCRIPTION l
II. SITE HISTORY < j
III. HIGHLIGHTS OF COMMUNITY PARTICIPATION 3
IV. SCOPE AND ROLE OF OPERABLE UNIT 4
V. SUMMARY OF SITE CHARACTERISTICS/EXTENT OF CONTAMINATION 4
VI. SUMMARY OF SITE RISKS 7
VII. DESCRIPTION OF ALTERNATIVES 8
VIII. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES 9
IX. SELECTED REMEDY n
X. STATUTORY DETERMINATIONS 12
XI. DOCUMENTATION OF SIGNIFICANT CHANGES 12
XII. RESPONSIVENESS SUMMARY 12
Xffl. REFERENCES 14
APPENDIX A - FIGURES
APPENDIX B - TABLES
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LIST OF FIGURES
FIQURE DESCRIPTION PAGE
1 Vicinity Map A_l
2 Facility Map A-2
3 Monitoring Well Locations A-3
4 Stratton Substation SRS Site Layout Map A-4
5 Stratton Substation SRS Site Layout Map A-5
6 . Area 1 0 - 0.5 Feet Contaminated Areas A-6
7 Area 1 0.5 - 1.0 Feet Contaminated Areas A-7
8 Area 1 1.0-2.0 Feet Contaminated Areas A-8
9 Area 1 2.0 - 3.0 Feet Contaminated Areas A-9
10 Area 1 3.0 - 4.0 Feet Contaminated Areas A-10
11 Area 2 0 - 0.5 Feet Contaminated Areas A-11
12 Area 2 0.5-1.0 Feet Contaminated Areas A-12
13 Supplemental Investigation Soil Sample Location Map A-13
14 Other Areas 0 - 0.5 Feet Contaminated Areas A-14
15 Area 1 Extent of Contamination at 0-0.5 Feet A-15
16 Area 1 Extent of Contamination at 0.5-1.0 Feet A-16
17 Area 1 Extent of Contamination at 1.0 - 2.0 Feet A-17
18 Area 1 Extent of Contamination at 2.0 - 3.0 Feet A-18
•19 Area 1 Extent of Contamination at 3.0-4.0 Feet A-19
20 Area 2 Extent of Contamination at 0-0.5 Feet A-20
21 Area 2 Extent of Contamination at 0.5 -1.0 Feet A-21
22 Other Areas Extent of Contamination at 0 - 0.5 Feet A-22
23 Other Areas Extent of Contamination at 0.5 -1.0 Feet A-23
24 Other Areas Extent of Contamination at 1.0 - 2.0 Feet A-24
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LIST OF TABLES
TABLE DESCRIPTION PAGE
1 Summary of Operable units under CERCLA Investigation 2
2 Area and Volume of Contaminated Soil Calculation B-l
3 Identification of Remedial Technologies B-3
4 Evaluation of Process Options B-6
5 Summary of Alternatives Evaluation B-8
6 Potential Chemical Specific ARARs for PCBs in Soil B-10
7 Action-Specific ARARs for Remediation B-11
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RECORD OF DECISION
NASA LANGLEY RESEARCH CENTER
STRATTON SUBSTATION OPERABLE UNIT
DECISION SUMMARY
1- SITE NAME. LOCATION. ANT) DESCRIPTION
NASA LaRC is a 787-acre NASA research center located in southeastern Virginia in the Hampton Roads area NASA
LaRC is bounded by State Route 172 on the West, by Brick Kiln Creek to the North and by Langley Air Force Base to
the South and East (Figure 1, Appendix A). NASA LaRC together with Langley Air Force Base was proposed to the
National Priorities List (NPL) in 1993. NPL listing was finalized in 1994.
The Stratton Substation OU is a major active electrical switchyard for the West Area of NASA LaRC and is located on
approximately 2.5 acres of land. The Stratton Substation OU is designated as Building 1233 and the fenced-in area
surrounding it, which lies on the northeast side of Stratton Road between Taylor Road and Warner Road (Figure 2
Appendix A), and comprises switch gear structures, a control house, and a pump house (Figure 3, Appendix A).
The site is located within the Atlantic Coastal Plain physiographic province. The geology of the area, primarily flat lying
marine sediments, consists of the Norfolk Formation and the Yorktown Formation. The uppermost soil unit at the site
consists of varying sequences of silt, clay, and silty to clayey sands belonging to the Norfolk Formation. In the boring
drilled for the Site Inspection, this unit occurs from 0 to 9 feet in depth and consists of brown, mottled orange and gray
soils. They are typically dry to moist and slightly to moderately plastic. The underlying Yorktown Formation consists
of gray silty clay and clayey silt with abundant shells and shell fragments. It is typically wet to saturated, moderately
to highly plastic and occasionally molded. Local sand lenses are common, as are partially hardened shelly layers
(coquina). The Yorktown Formation extends to approximately 400 feet below grade at the site.
Groundwater in the area can be found at a depth of 5 to 50 feet below the land surface. This aquifer, known as the
Columbia aquifer, is brackish and is limited to lawn and garden watering. Both the Yorktown and the Yorktown-
Eastover aquifers underlie the Columbia aquifer. The Yorktown-Eastover aquifer is confined and is used as a source
of domestic potable water.
EL SITE HISTORY
This section describes the Site history, history of waste disposal, and CERCLA investigations response actions at the
Site.
A. HISTORY OF THE SITE
NASA LaRC was the first national research laboratory dedicated to aviation. Groundbreaking took place on June 7,
1917 under the authority of the National Advisory Committee for Aeronautics (NACA), created by Congress in 1915.
Prior to 1917, the property was used for agriculture.
In 1920, NASA LaRC was dedicated and the world's first wind tunnel was completed at the facility. The goal of NASA
LaRC was to advance the understanding of aerodynamics. During World War II, NASA LaRC began studying space
travel in response to German rocket testing. In the 1960's the Mercury Astronauts were trained at NASA LaRC. This
ended in 1962 when the manned space center in Houston was opened. Since the 1970's, NASA LaRC has focused on
testing Space Shuttle Systems and unmanned Viking probes.
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B. HISTORY OF WASTE DISPOSAL
The primary functon of NASA LaRC is the research and development of advanced technologies for aircraft and
spacecraft. Specific studies center on instrumentation, materials fatigue, acoustics, aerodynamics, and guidance control
In conducting its research and development mission, NASA LaRC requires many support facilities including
Underground Storage Tanks (USTs) for fuel and other raw products, power plants, JriJSnneb, laboratories 1'
administrative buildings. All of these facilities have the potential to impact the environment through disposal activities
materials) transportation and inadvertent releases such as spills or mechanical malfunctions.
There are currently 6 Operable Units being investigated under CERCLA at NASA LaRC. They include- the
Construction Debns Landfill, the Chemical Waste Pit, Area E Warehouse, Tabbs Creek, Stratton Substation
Groundwater, and Stratton Substation (soils). A brief summary of these areas is provided on Table 1 Figure 2
(Appendix A) provides the location of these areas. Records of Decision have been signed by NASA and EPA for the
Area E Warehouse OU and the Tabbs Creek OU. The Construction Debris Landfill, Chemical Waste Pit and Stratton
Substation Groundwater will be addressed in future RODs.
Table 1. Summary of Operable Units Under CERCLA Investigations
OUName
Findings
Current Status
Construction Debris Landfill
Organic and inorganic
contaminants found in
groundwater, surface water,
sediment, and soil.
NASA preparing response to regulator
comments on the draft Remedial
Investigation/Feasibility Study
Chemical Waste Pit
Chemical wastes reportedly buried
at the site.
Chemical Waste Pit was found to be
located within the boundaries of the
Construction Debris Landfill (CDL)
OU and is addressed in the CDL RI/FS.
Area E Warehouse
Low levels of Polychlorinated
Biphenyls (PCBs) and metals
contaminated soils.
Record of Decision was signed on 30
September 1998. Remedy is the
implementation of institutional controls
(land use restrictions). The survey plat
required as part of the remedy has been
prepared.
Tabbs Creek
PCB/PCT contaminated sediment.
Record of Decision signed on 30
September 1998. Remedy involves
dredging and off-site disposal of
contaminated sediment. NASA is
currently preparing responses to
regulator comments on the draft
Remediation Work Plan.
Stratton Substation Groundwater
PCB contaminated groundwater
Monitoring wells will be sampled upon
completion of the Stratton Substation
soil remedial action. A focused RI/FS
report will be prepared based on the
groundwater sampling effort.
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C. CERCLA INVESTIGATIONS
NASA completed CERCLA Preliminary Assessment (PA) and Site Inspection (SI) Reports in 1988 and 1989
respectively. In 1993, NASA LaRC, together with Langley Air Force Base (LAFB), was proposed for inclusion on the
National Priorities List (NPL) and included on the NPL in 1994. A Federal Facilities Agreement (FFA) was signed by
EPA, NASA and the Virginia Department of Environmental Quality (VDEQ) in 1994. The FFA establishes a procedural
framework and schedule for implementing site cleanups at NASA LaRC (the Site).
PCBs were detected in 1984 in two areas (Areas 1 and 2; Figure 5, Appendix A) in the soil adjacent to the pump house
at the Stratton Substation OU. Between 1984 and February 1987, the focus of site investigations was directed primarily
toward soil contamination; a total of three removal actions were completed.
A Focused Feasibility Study was performed by NASA in 1996 and 1997. The investigation consisted of sampling and
analysis of surface and subsurface soils. The on-site screening analysis indicated the presence of PCB 1260 only in
isolated pockets, in both areas and at two locations near the control room, within the limits of the Stratton Substation
OU. The detected PCB concentration ranged from non-detect to a maximum of 1100 ppm in Area 1, from non-detect
to a maximum of 49 ppm in Area 2, and from non-detect to a maximum of 333 ppm in other areas within the limits
of the yard The results were used to conduct a human health risk assessment.
HL HIGHLIGHTS OF COMMUNITY PARTICIPATION
In accordance with Sections 113 and 117 of CERCLA, 42 U.S.C. Sections 9613 and 9617, NASA, in conjunction with
EPA, issued a Proposed Plan on March 1, 1999, presenting the preferred remedial alternative for the Stratton Substation
OU. The Proposed Plan and the supporting documentation became available for review at that time and are among the
documents which comprise the CERCLA Administrative Record for NASA LaRC.
The Administrative Record is available for review by the public at the following information repositories:
Poquoson Public Library
800 City Hall Avenue
Poquoson, Virginia
Floyd L. Thompson Library
NASA LaRC
Hampton, Virginia
An announcement for a public meeting, the comment period, and the availability of the Administrative Record for the
remedy for the Stratton Substation OU was published in the Daily Press on February 28, 1999. Additionally, the Notice
of Availability was mailed to local municipal and government agencies and residents in the vicinity of the Site. The
public comment period for the Proposed Plan was from March 1, 1999 to April 14, 1999. A public availability session
was held at the Virginia Air and Space museum in Hampton, Virginia on March 17, 1999 to inform the public of all the
remedial alternatives and to seek public comments. At this meeting, representatives from NASA, USEPA, VDEQ and
Foster Wheeler (an environmental consultant) were available to answer questions about conditions at the site and the
remedial alternatives under consideration. Responses to the comments received during this period are included in the
Responsiveness Summary section of this ROD.
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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f- SCOPE AND ROLE OF THIS BEME1HAT
Discrete portions of an NPL site are often managed more effectively as Operable Units. NASA has organized work
to
Construction Debris Landfill
Chemical Waste Pit
Area E Warehouse
Tabbs Creek
Stratton Substation Groundwater
These five remaining Operable Units are currently being independently investigated under CERCLA and either have
been or will be addressed in separate Records of Decision. See Table 1 discussion.
V' ?VMMARY OF SITE CHAR ACTERISTTf S 4ND EXTENT QF
Summarized below are the relevant findings of the work to date with regard to Site characteristics and contaminated soil
located within the boundaries of the NASA LaRC including the Stratton Substation OU.
A. SITE CHARACTERISTICS
1. Geology
LaRC is situated within the Atlantic Coastal Plain physiographic province, which consists of an eastward thickening
sedimentary wedge composed of unconsolidated gravels, sands, silts, and clays, with variable amounts of marine fossils
LaRC is underlain by approximately 2,000 feet of unconsolidated sediments.
The uppermost soil units (excluding fill material) are Holocene age deposits and Pleistocene deposits of the Norfolk
Formatioa Holocene deposits, consisting of organic clays, silts, and silty clays, are encountered in proximity to the
margins of tidal estuaries that border LaRC. These deposits are up to 30 feet thick along the northern border of the
facility. Away from the tidal estuaries, surface soils consist of the Norfolk Formation, a member of the Pleistocene Age
Columbia Group. Soils of the Norfolk Formation consist of sequences of silt, clay, and silty to clayey sands that are
typically dry to moist and slightly to moderately plastic. An erosional surface separates this unit from the underlying
Bacons Castle Formation.
The Pliocene Age Bacon Castle Formation, composed of the Moore House Member, occurs at depths of 50 to 60 feet
at LaRC. The Moore House Member consists of sequences of silty sands containing marl and shell hash lenses These
marl and hash lenses are absent at some locations. The Mogarts Beach Member of the Yorktown Formation is
encountered at depths of 70 to 80 feet The Mogarts Beach Member is a distinctive hydrologic unit consisting of blue
clay of up to 15 feet in thickness; however, it is absent at some locations.
2. Hydrogeotogy
Groundwater in the area can be found at a depth of 5 to 50 feet below the land surface. This aquifer, known as the
Columbia aquifer, is brackish and, its use is limited to lawn and garden watering. Both the Yor.ktown and 'the Yorktown-
Eastover aquifers underlie the Columbia aquifer. The Yorktown-Eastover aquifer is confined and is used as a source
of domestic potable water. Groundwater is not being addressed as part of this remedial action.
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3. Meteorology
The climate at the Site is characterized by mild winters and warm and humid summers. The climate is affected by the
Chesapeake Bay and Atlantic Ocean to the east and mountains to the west. During the winter, temperatures reach a high
of near 50 with lows in the 30s. In the summer, the highs are generally in the 80s with lows around 70.
The mean annual precipitation at the Site is 44.15 inches. Maximum precipitation occurs in July and August, while the
minimum occurs in November and April. However, precipitation is distributed throughout the year. The average number
of days with precipitation ranges from 7 to 11 days per month and 110 days per year. Snowfall in the winter averages
10 inches per year, however, it is extremely variable, ranging annually from 0 to 45 inches.
The prevailing wind direction is south-southwest in April and May, southwest in June to September, and north in October
to March. The average wind speed is 5 to 8 knots.
4. Ecology
Open land, woodland, wetland and aquatic habitats are all found within or near NASA LaRC. These include mowed
fields and lawns, nonfbrested overgrown land, wooded areas, forested wetlands, scrub/shrub wetlands, creeks, tributaries
and steams.
5. Soils
Soil at the Stratton Substation OU consist of a thin (3 feet) surface layer of fine sandy and silty clays, typical of the
Columbia Group.
B. NATURE AND EXTENT OF CONTAMINATION
Polychlorinated biphenyls (PCBs) were detected in 1984 in two areas (Areas 1 and 2, Figure 5, Appendix A) in the soil
adjacent to the pump house. Between 1984 and February 1997, a total of three removal actions were completed.
Residual soil contamination (less than 50 ppm) remained at the site.
As part of the Focused Feasibility Study (FFS) two investigations were conducted on the soils at the Stratton Substation
OU. The initial investigation was concentrated only to the two areas (Areas 1 and 2, Figure 5, Appendix A) adjacent
to the Pump House. Following the initial investigation, a supplemental investigation was concentrated outside the two
areas (Areas 1 and 2) within and just outside the fenced-in limits of the yard.
The following is a summary of the sampling results of the FFS.
Within the fenced-in area of the Stratton Substation OU a gravel layer is present, especially at Area 1. The thickness
of the gravel varied within each area and the thickness ranges from 3- to 8- inches in Area 1 and from 1 - to 5- inches in
Area 2.
The on-site screening analysis indicated the presence of PCB 1260 only in isolated pockets, in both areas and at two
locations near the control room, within the limits of the Stratton Substation OU. The detected PCB concentration ranged
from non-detect to a maximum of 1100 ppm in Area 1, from non-detect to a maximum of 49 ppm in Area 2, and from
non-detect to a maximum of 333 ppm in other areas within the limits of the yard.
1. Area 1
The surface soil (0.0 to 0.5 foot interval) samples indicated presence of PCB contamination within this Area (Figure 6,
Appendix A). Within Area 1 the extent of contamination is isolated to three subareas (Figure 6, Appendix A). Subarea
1 included soil sample locations 3, 8 and 14. The detected PCB concentrations ranged from 71.1 to 1100 ppm. Subarea
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2 included soil sample locations 10, 11. and 22. The detected PCB concentrations ranged from 120 to 1000 ppm
m "° IOCati°n 33' ^
S I mt "°? T^ IOCati°n 33' ^ detected ««««« at this location was 60 pmPCBs were not
detected from the sample located underneath the driveway.
The subsurface soil samples also indicated presence of PCB contamination in isolated spots, especially in two of the three
subareas (Figure ,7 Appendix A). For the 0.5 to 1.0 foot interval, sample location 8 in S^ea 1 uScated ! KB
r^f^t°n? f47?PPm-whereas sample location " in Subarea 2 indicated a PCB concentration of 93.4 ppm At 10
to 2.0 foot mterval, sample location 1 1 in Subarea 2, indicated the presence of PCB at 40 to 67.4 ppm (Figure 8
X?7 { H ,f?Qint^^PlelMad°M I0and U -Subarea 2 (Figure 9, AppendiL) hK*
m A "5 I\ T* "?*«*"**• At *« 3'° to 4-° ft** interval, sample locations 10 and 11 in
10, Appendix A) indicated presence of PCB at 144.5 and 24.2 ppm, respectively.
two subsurface soil »»Pl« fr°n> the 1 to 2 foot and 2 to 3 foot intervals were
, Qe 10CatiOD SRS1-°8' Both samPles mdicated Presenc* <* PCBs at 36.9 an™
f 9' APP6"** A>' Al» at Sample location SRS1-22, two subsurface soil samples were
. Samples collected from 0.5 to 1 foot and 1 to 2 foot intervals indicated presence of Aroclor 1 260
at 284.9 and 1 36 ppm, respectively (Figures 7 and 8, Appendix A).
An additional soil sample was added, SRS1-54, to further delineate the extent of contamination from sample point SRS1-
33 (Figure : 6, Appendix A). Both surface and subsurface samples were collected and subjected to on-site screening
analysis. None of the samples indicated presence of PCBs at levels exceeding 10 ppm.
2. Area 2
The surface soil (0.0 to 0.5 foot interval) samples had the most contamination within this area (Figure 11 Appendix A)
Within Area 2 the extent of contamination is isolated to two Subareas (Figure 11, Appendix A). Subarea 'l includes soil
sample location 11. The detected PCB concentration was at 44.8 ppm. Subarea 2 includes soil sample locations 4 and
9. TJie detected concentration ranged from 20.6 ppm to 35.5 ppm.
The subsurface soils also indicated presence of PCB contamination in an isolated spot in one of the two Subareas At
0.5 to 10 foot interval, sample location 11 in Subarea 1 (Figure 12, Appendix A) indicated a PCB concentration of 28
ppm to 48.8 ppm.
3. Other Areas - North of Concrete Driveway
None of the samples collected from the northern half of the site indicated the presence of PCBs at significant levels The
detected concentrations ranged from non-detect to a maximum of 2.2 ppm in the surface soil (0.0 to 0.5 foot) samples
from 14 duTerent locations (SRS1-40 through SRS1-53; Figure 13, Appendix A). At five of the fourteen locations based
on surficial discoloration of the soil, a subsurface soil (0.5 to 1 feet) sample was also collected for on-site analysis. The
Aroclor 1260 was detected at concentrations from non-detect to 0.4 ppm in these subsurface soil samples.
4. Other Areas - South of Concrete Driveway
Thirteen sample locations were selected to represent the southern half of the site (SRS2-25 through SRS2-37 in Figure
13, Appendix A). The majority of the surface soil samples (11 of 13) indicated presence of PCBs at trace levels from
non-detect to 0.4 ppm. PCBs were detected in two of the 13 surface samples at 16 ppm at SRS2-28 (0-0.5 foot interval)
and at 21.7 ppm at SRS2-34 (0 to 0.5 foot interval). The area surrounding these two sample locations is identified as
Contaminated Areas F and G (Figure 14, Appendix A).
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VI. SUMMARY OF S1TF
Human Health Risk
Health risks are based on a conservative estimate of the potential carcinogenic risk or potential to cause other health
effects not related to cancer. Carcinogenic risks and noncarcinogenic risks were evaluated as part of the nsk assessment-
three factors were considered:
1. nature and extent of contaminants at the OU,
2. the pathways through which human receptors are or may be exposed to those contaminants at the OU, and
3. 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 Surface
water and sediment were not evaluated because human receptors are not exposed to this medium at this OU
Groundwater for this OU will be investigated upon the completion of this remedial action and addressed in a separate
ROD.
Cancer risks are expressed as a number 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 soil at the OU for 30 years For
example, EPA's acceptable risk range for cancer is 1 x lO"4 to 1 x 10s, meaning there is one additional chance in ten
thousand (1 x lO"4) to one additional chance in one million (1 x 10*) that a person will develop cancer if exposed to a
hazardous waste site.
Direct contact, including oral and dermal exposures of contaminated soils for LaRC workers was calculated for the risk
assessment. The lifetime cancer risk from PCS exposure for the worker at the Stratum Substation OU is calculated at
1.5 x IQ-4. This lifetime cancer risk exceeds EPA's acceptable risk range of 1 x 10* to 1 x 10"*.
Ecological Risk Assessment
Due to the characteristics of the OU (i.e., fenced-in gravel covered area, no surface water bodies in the immediate
vicinity of the OU), exposure to ecological receptors, including aquatic and terrestrial receptors, to contaminated soil
is unlikely; the exposure pathway is incomplete. Therefore, an ecological risk assessment was not performed.
C. CONCLUSIONS
The remedial objective for the Stratton Substation OU is to protect human health and the environment. As indicated
above, the risk posed to the worker exceeds EPA's acceptable risk range. Based on available information, and standards
such as applicable or relevant and appropriate requirements of federal and state law (ARARs), and risk-based levels
established in the risk assessments, the specific remedial objectives for the Stratton Substation OU are presented as
follows:
Soil
The human health risk assessment concluded that direct exposure to contaminated soil would pose a cancer risk which
exceeds the EPA's acceptable risk range of 10* to 10". In view of the results of the human health risk assessment, the
remedial action objective for the soil would be to remediate PCBs in the soil to a level that is protective of human health.
An additional objective is to assure that the property use does not allow non-industrial exposure to soils. A cleanup level
of 10 ppm of PCBs is recommended for the Stratton Substation OU and is based on the protection of human health.
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Contaminated Soil Areas and Volumes
The soil sampling results indicated that the surface and subsurface soils in four separate areas, southwest (Area I) and
southeast (Area II) corner areas of the pump house and northwest and northeast corner areas of the control room, were
contaminated with elevated concentrations of PCBs.
By comparing the sampling data to the cleanup level of 10 ppm, three small isolated contamination areas were identified
in Area I. Two of the areas are adjacent to the previous excavated area along the concrete driveway The total
contaminated area in Area I is estimated at 1280 square feet and 480 square feet and is depicted in layers in Figures 15
through 19 (Appendix A). The aerial extent of contamination was estimated based on the assumption that the PCS
concentrauon of a sample point represented an area concentration within a 12 foot radius from the sample point The
physical barriers, i.e., building and concrete driveway, and the extent of the previous excavated area were also taken into
account. By using the same method, two isolated contamination areas were identified in Area II, and two areas near the
control room exceeding the cleanup level. The total contaminated area of Area II was estimated at 480 square feet and
is depicted in layers in Figures 20 and 21 (Appendix A). The total contaminated areas in the control room were estimated
at 300 square feet and are depicted in Figures 22 through 24.
As seen in Figure 19, PCB contamination has extended to a three to four foot range below ground surface at subareas Bl
and B2 located in Area I. Since no subsurface samples were collected beyond 4 feet deep from the ground surface, six
feet of PCB contamination is assumed; however, the limits of excavation will be determined through confirmation
samples. Similarly, there were no samples collected beyond three feet at Subarea A2 and two feet at Subarea G2. Four
feet of excavation was assumed for both areas. Consequently, the contaminated soil volume was estimated at 212 cubic
yards. Table 2 (Appendix B) provides detailed calculation of contaminated soil areas and volumes.
DESCRIPTION OF ALTERNATIVE?
The soil remediation technologies were identified and screened using effectiveness and implementability as the criteria.
The screening process is described in Table 3 (Appendix B). Table 4 (Appendix B) summarizes the process options that
were retained to form alternatives. Using these retained process options, three alternatives: 1) no-action; 2)
excavation/off-site incineration; and 3) excavation/off-site disposal in a TSCA landfill were developed for detailed
analysis as follows.
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 at this time to address contaminated soil at the Stratton
Substation OU.
Capital Cost: $0
Operations and maintenance (O & M) cost: $0
Net Present Worth: $0
Alternative 2: Excavation/Off-Site Incineration
This alternative involves the excavation of soil with concentrations greater than 10 ppm, estimated at 190 cubic yards.
The contaminated soil would be hauled to a permitted off-site facility for incineration. The excavated areas would be
backfilled with clean fill material and regraded as needed to existing conditions. Use restrictions will be imposed to limit
the site use to industrial purposes only. This will include the preparation of a survey plat which will state the land use
restrictions that have been placed on the property and will indicate the boundaries of the OU. This plat will be submitted
to the local recording authority. These use restrictions will also be incorporated into the NASA LaRC Base Master Plan.
8
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In addition, the presence of the existing security fence around the OU serves to limit access to the OU Although the
purpose of the fence around the OU is for providing security (its presence and maintenance is not part of this alternative)
it also limits the individuals who may be exposed to the contaminated soils by preventing unauthorized access.
Capital Cost $445,000
Annual O&M Cost $500
Present Worth $ 461,000
It is anticipated that the time required to achieve remedial action objectives for this alternative is approximately 3
months; 2 months for the preparation and approval of the design; 1 week for site preparation; 1 week for excavation- and
1 week for demobilization.
Alternative 3: Excavation/Off-Site Disposal
This alternative is identical to Alternative 2 except excavated soil will be disposed in a TSCA permitted landfill.
Capital Cost $294,000
Annual O&M Cost $500
Present Worth $301,000
As with Alternative 2, it is anticipated that the time required to achieve remedial action objectives is approximately 3
months.
VOL 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 or relevant and appropriate
requirements (ARARs); long-term effectiveness and permanence; reduction of toxicity, mobility, or volume; short-term
effectiveness; implementability; cost; regulatory acceptance; and community acceptance.
A comparative analysis for the three alternatives based on these evaluation criteria is presented in the following sections.
In addition. Table 5 (Appendix B) provides a summary of contaminated soil remedial alternatives evaluation.
A. OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
Alternative 1 provides no remedial action and the soils at the Stratum Substation OU continue to be contaminated.
Alternatives 2 and 3 would provide protection to human health and the environment from exposure to the contaminated
soil since soils with contamination above the cleanup levels for PCBs would be removed from the site. With off-site
disposal of contaminated soil, Alternative 3 would contain contaminants in a controlled environment (i.e., TSCA
landfill). With ofE-site incineration, Alternative 2 would destroy the contaminants. Alternative 2 would be most effective
because the destruction process is not reversible. However, Alternative 3 also meets this criteria because it provides
protection of human health and the environment and is more cost effective than Alternative 2.
B. COMPLIANCE WITH ARARS
TSCA requirements for disposal of PCB contaminated soils is applicable and therefore an action-specific ARAR for
contaminated soil. The cleanup level was derived to protect the workers at the OU. Alternatives 2 and 3 would meet
the cleanup level by removing the soil with contamination exceeding the level and treating/disposing the soil at an offsite
facility. These alternatives would meet the remedial action objectives. For Alternative 1, the cleanup level would not
be attained. (Specific ARARs for the remedy in this case are identified in Tables 6 and 7 in Appendix B of this ROD).
-------
C. LONG-TERM EFFECTIVENESS AND PERMANENCE
Alternatives 2 and 3 would be effective in addressing the site contaminants since the soil with contamination above the
£S?f f «*p"*? removed from the site. Alternative 2 would be most effective inTfongte™ since
° C°ntammated '1* n0t revffsible «« does not ^uire long-term maintenance. AlternaUveT^d
probablybe required "^ ^^ "* ^ °f """^ *"" ** COntaminated ** tberefi»«. **«« remedial actions would
D. REDUCTION OF TOXICITY, MOBILITY, OR VOLUME THROUGH TREATMENT
Alternative 2 would reduce the toxicity, mobility, and volume of contaminated soil at the Stratton Substation OU through
n^em; AJtemaUvTVJ does not "M*™ *»****• Alternative 1 would not reduce the toxicity, mobility, or volume
of the contaminants. The treatment process under Alternative 2 is irreversible. Although Alternative 3 doi not reduce
toxicity mobility or volume through treatment, it is protective of human health and the environment and more cost-
effective than Alternative 2. In addition, principal threats for which treatment is most likely to be appropriate include
liquids areas contaminated with high concentrations of toxic compounds, and highly mobile materials. Conditions at
the Stratton Substation OU do not meet these criteria to warrant treatment, but do warrant removal of contaminated soil.
E. SHORT-TERM EFFECTIVENESS
Alternative 1 would not involve any construction activities; therefore, it would provide the least short-term risks to the
community, workers, and the environment.
Alternatives 2 and 3 would require excavating and handling of contaminated soil, posing some risk of contact to workers
and residents. Engineering measures would be implemented to protect the workers and the community They may also
cause a traffic inconvenience to neighboring communities.
Once on-site work begins, Alternatives 2 and 3 would require approximately 3 weeks to complete. Alternative 1 does
not involve any on-site work and does not meet remedial action objectives.
F. IMPUEMENTABELITY
Alternative 1 would be the easiest alternative to implement since no construction activities would be performed at the
Stratton Substation OU.
Alternatives 2 and 3 would involve removal of the contaminated soil from the area. Excavating and waste transporting
would use common equipment and procedures. Incineration and landfilling in Alternatives 2 and 3 are also common
and proven technologies utilized in PCB remediation. After removal of contaminated soil, clean material would be used
to backfill the excavated area.
G. COST
Alternative 1 has no cost associated with implementation. Alternative 2 would eliminate long-term maintenance costs
and reduce toxicity, mobility, and volume at a significant increase in cost over the other alternatives. Alternative 3 would
provide similar protection to Alternative 2, but at one third the cost Alternative 3 is the more cost-effective alternative.
It will meet all remediation goals (in contrast to Alternative t) with significantly less cost than Alternative 2.
10
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H. STATE ACCEPTANCE
The Virginia Department of Environmental Quality concurs with the selection of Alternative 3, Excavation and Off-Site
Disposal and Institutional Controls as the selected remedy for this OU.
L COMMUNITY ACCEPTANCE
An availability session on the Proposed Plan was held on March 17, 1999 in Hampton, Virginia. Comments received
orally and/or in writing at the availability session are referenced in the Responsiveness Summary (Section XII of this
ROD). There was no public opposition to proposed remedy.
EX. SELECTED REMEDY
Following review and consideration of die information in the Administrative Record file, requirements of CERCLA and
the NCP, and the public comments reviewed on the Proposed Remedial Action Plan, NASA and EPA in consultation
with VDEQ, have selected Alternative 3: Excavation/Off-Site Disposal and Institutional Controls as the remedy for the
Stratton Substation Operable Unit. This remedy would prevent unacceptable exposure to contaminated soil.
Based on available information, NASA 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-ofls among the alternatives
with respect to the evaluation criteria.
The selected remedy for the Stratton Substation OU includes the following major components:
1) excavation of soils with concentrations greater than 10 parts per million (ppm), estimated at 212 cubic
yards;
2) transporting and disposing of the soils off-site to a Toxics Substances Control Act (TSCA) - approved
chemical waste landfill;
3) backfilling excavated areas with clean fill material;
4) the prohibition of use of the property for purposes other than industrial (e.g., residential, child care or
recreational use);
5) inputting these restrictions in the NASA LaRC Master Plan;
6) within 90 days of ROD signature, NASA shall produce a survey plat prepared by a professional land
surveyor registered by the Commonwealth of Virginia indicating the location and dimensions of the
Stratton Substation Operable Unit and the extent of the soil contamination. The plat shall contain a note,
prominently displayed, which states the owner's future obligation to restrict the land use of the property.
The plat shall be submitted to the local recording authority;
7) NASA shall incorporate these restrictions and supply a copy of the plat into any real property
documents necessary for transferring ownership from NASA, in the unlikely event that NASA sells 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 contamination;
8) The NASA LaRC Environmental Engineering Office Head will certify to USEPA on an annual basis
that there have been no violations of these prohibitions. If a violation has occurred, a description of the
violation and corrective actions to be taken will be provided.
The present worth of this remedy is $301,000.
PERFORMANCE STANDARDS
Excavation/Off-Site disposal shall remove all soils with concentrations greater than 10 ppm. This includes excavating
to a depth of 6 feet in certain areas.
11
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X. STATUTORY DETERMmATT9NS
A. PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The selected remedy. Alternative 3, would protect human health and the environment by preventing exposure through
the removal (excavation) of the contaminated soils and containment in a landfill designed to store PCBs.
B. COMPLIANCE WITH ARARS
The selected remedy will comply with all ARARs including TSCA (see Tables 6 and 7, Appendix B) The remedial
action objectives will be met by the selected alternative since the contaminated soil in excess of the cleanup level will
be removed.
The selected alternative will comply with action-specific ARARs which include OSHA, transportation and disposal
regulations (see Table 7, Appendix B).
C. COST EFFECTIVENESS
The selected remedy is cost-effective. The present worth cost is $301,000.
D. UTILIZATION OF PERMANENT SOLUTIONS AND ALTERNATE TREATMENT TECHNOLOGIES
OR RESOURCE RECOVERY TECHNOLOGIES TO THE MAXIMUM EXTENT PRACTICABLE
The removal of contaminated soil in the selected alternative would permanently reduce the volume of contaminants at
the Stratton Substation OU. After the remedial action is completed, residual risks around the site would be within an
acceptable level. Off-site disposal of contaminated soil in a landfill would control the mobility of the contaminants.
The selected remedy does not utilize permanent treatment technologies for this site due to cost and other considerations.
Although this action does not fully address the statutory mandate for treatment, this action provides for a permanent
remedy and thus partially satisfies this mandate.
E. PREFERENCE FOR TREATMENT AS A PRINCIPLE ELEMENT
The selected alternative does not treat the contaminants. However, excavation and off-site disposal are proven and
reliable technologies, and would achieve the remedial action objectives as effectively as the treatment alternative at the
site.
XL DOCUMENTATION OF SIGNIFICANT CHANGES
The proposed plan for the Stratton Substation OU was released for public comment on March 1, 1999. The Proposed
Plan identified Alternative 3, Excavation/Off-Site Disposal and Institutional Controls, as the preferred alternative.
NASA, EPA and VDEQ reviewed and considered all comments received during the public meeting and during the public
comment period. Upon review of these comments, it was determined that no significant changes to the remedy, as
originally identified in the Proposed Plan, are necessary.
XIL RESPONSIVENESS SUMMARY
OVERVIEW
In a Proposed Plan released for public comment on March I, 1999, NASA, with the support of EPA, identified
Alternative 3 as the preferred remedial alternative for the Stratton Substation OU at the Site. Alternative 3 in the
Proposed Plan was described in Section VIII; there was no public opposition to the proposed remedy.
12
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COMMUNITY INVOLVEMENT TO DATE
NASA and EPA established a public comment period from March 1, 1999 to April 14 1999 for interested
for Ae a*°n substation ou-
re
hS Sen !n 1 ^ PrOC6SS •**' *" ^^ Substati°n °U m ™l»ded * «* Administrative Record, *
She f reOSlt
l7' 1999 to present the Proposed Plan, answer
RECEIVED DUMNG ™ PUBUC COMMENT PERIOD AND
Although no one attended the public meeting, prior to the start of the public meeting, a Technical Review Committee
(TRC) meeting was held at whch tune the Stratton Substation Proposed Plan was discussed. The following comments
were raised during the TRC meeting:
Comment 1 : What is the difference between Alternative 2 and Alternative 3?
Response 1 : Both alternatives excavate the contaminated soil. Alternative 2 involves incineration in an off-site facility
Alternative 3 involves disposal in an off-site landfill.
Comment 2: What is the cost difference?
Response 2: Alternative 2 costs $461,000 and Alternative 3 costs $301,000.
Comment 3: Where will the contaminated soil be disposed?
Response 3: In a TSCA-approved landfill. The exact location has not yet been determined, however there are no TSCA-
approved landfills in Virginia, so it would be transported out of state.
13
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XHL REFERENCES
Foster Wheeler Environmental, 1996. Final Field Sampling and Analysis Plan, Focused Feasibility Study Investigation
for Stratton Substation Site, NASA Langley Research Center, Hampton, Virginia.
Foster Wheeler Environmental, 1998. Final Focused Feasibility Study Report for Stratton Substation Site, NASA
Langley Research Center, Hampton, Virginia.
14
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APPENDIX A
FIGURES
-------
-------
i-v
-------
Contaminated Sites
NASA-1
NASA-2
NASA-3
NASA-4
NASA-5
NASA-6
Chemical Waste Pit
Construction Debris Land/1
Tabbs Creek
Stratton Substation
Stormwater System
Warehouse Area
NASA LaRC West Area Contaminated Site Locations
M\SA
-------
.
MMtntuiH, nu toanan
atturoN FOAO snmnon
HMA 1IUI«UI MSEMtea CEHTtR
-------
AREA 1 SEE
FIGURE 2-t
PUMP HOUSE -i
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FIGURE 2-2
VICTORY ST.
LEGENDr
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2nd EXCAVATION 0-3'
D
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STRATTON SUBSTATION SRS SITE
LAYOUT MAP
NASA LANGLEY RESEARCH CENTER
Foster Wheeler Environmental
QMS
= 2/»7
NASA\TON«4\»*-FI-2
A-4
-------
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LAYOUT MAP
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QMS
| DATE- 2/97 H»SA\TON94\9*-FI
A-5
-------
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-------
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OMS
DATE: 2/97
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-------
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DATE: 11-M
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-------
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APPElsfDIXB
TABLES
-------
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Tiblcl
Art • and VolHMe ofCo»u*lMled Soil Cilculnlon
AttU:
Al
A2
Bl
B2
C
Soil Total
Gnvd
Arc* (Total
AttiJ:
O
E
Soil Total
Gravel
Aita2Total
Area
(If)
500
30
370
310
SO
I2U
703
310
100
410
100
Deepest Depth
•hove PCB
Cleanup Level
(ft)
O.S
3.0
4.0
4.0
0.3
0.3
1.0
Depth Range
below PCB
Cleanup Level
(ft)
0.3-1.0
unknown
unknown
unknown
0.3-1.0
0.3 • 1.0
1.0.2.0
Depth
Assumed
(ft)
0.3
4.0
6.0'
60'
0.3
0.3'
0.3
1.0
0.3»
Volume
(ft')
230
200
2.220
I.2401
23
3,7«S
333
4.2)1
(137 cy)
190
100
290
30
340
(13 cy)
-------
Are. nd Voltme ofCcmii.lMted Sell CatcMltilM
s
Section
Other Arejj:
F
01
G2
Soil Total
Gnvd
Other Areas Total
1 Assume the depth of conta
* The coMaminalnl mil in E
1 Assume the (ravel cover al
in average.
^mmmKm===aE=af^^^
Area
(ft1)
SO
300
150
500
425
"I' • i-»*^-~ii-».^—i ^
Deepest Depth
above'PCB
Ckanup Level
(•)
^•^•••KiiiMMIXBIBM^HMW
0.5
1.0
2.0
minatiw for sections BI and B2 b 6 • awl for sections A2
12 area begins 2 ft below (he surfidal soil.
bove the eontamioaled toil is coMaawaled and 0.5 ft thick
Depth Ranfe
below PCB
Cleanup Level
(A)
—^^•—— •— — ™
0.5-1.0
1.0-2.0
UOIUWWR
MMBBMIiHMKMmniMMn
MdG2is4ft.
Depth
Assumed
(ft)
••i*«»»>«iliBMI»M«.
0.5
1.0
4.0
0.5
"•in ' ••••••^•^
VoiliOK
(ft1)
^^*— •—«—•-•«•
25
300
600
925
213
1.131
(42 cy)
^MMiHII^HBUMMM^^..
-------
B-3
-------
-------
|
is
I!
I
h
i !
•i *
I 1 J
j
•s-
I i
V JS
* * a w
I ill
*
1
.5
s
1
B-5
-------
9-a
-------
09
Evaluation of Proem OpKoM
Remedial
Technology
'mptencatabtlity
De«*looaaUoa£G)
EflectivcMdcskiKtionafPCBs. Limited
Medium capital,
few 0AM.
•*miPiwc0(BCD)
Ofrsite: High
capital, no QAM
Medium
capital. w> CAM
Uw-fcmpenwic iMcrmal
DMomtion
Vitrification
demonstraled « other namdout wane
Only one commercial unit is available Small waste
volume b MM cost^flctlive to be treated on*sile.
«•» to eamd and destroy PCB«,
Effective MdesinKtioa of PCSs.
Medium capital.
noOAM.
Nocomnwwalsysiemewst
United experience. No commenial system exists.
UmNedexpctknce. No commercial system exisu.
DesoipiionciidVapof
EOcctivc in icnwml ofPCBs Switoa.
Easily implemented Considered by some not be •
" " technology.
•»b*«X«fPCBiinioSl
Low capital and
0AM.
Piooesi oouM be icvcned under adwne oondiiiont
mchmlowpH.
Eflective in disposiag Heated soil may not be
because of low mobility of PCBs in soil
Easily implemented.
Low capital, low
0AM.
-------
T«MeS
Smmmtry of Alterative* Evilmtioi
ALTERNATIVE I
NO ACTION
ALTERNATIVE 2
EXCAVATlON/OFF-SrTE INC&CRAHON
00
Qsssutia*
Risk to MM* healn Md Ike cuvkanail would KM*
IHII; M jdtMjfied M toMiiiie ifak
IUstotoliiMMlicil*iKw>*MEf»ArtpDuiidwMer.
and icstore ne site. Impfanetf use icuridioii.
iVolecblH«MMlieaWiMd»e<»vinMMeiri. Risk to
MMWI heaUi Md the CUVWOMM* §OM conunMnMed
Comply win UK TSCA rawiieaieMs nd danup goali
Locstion of site does MM ki^er loartiMMpecific ARARs.
CommiclMM Ktivitki would coMply with •dkw-spccifk
ARARs.
Elfective M dimiMliat> risk by nmovin« souree of
rm.l».i.«in> to ae ctamy level. Reduces iM|nikm of
proccn but am be rctobk if Mi^yd property
-------
s
31
*>
i
u
i
i
X
ta
li
.fi
•s
i!i
I" .6 S
^ "^
11
^
11*
!IS
Jfi
Jf
!l
J!
.-1
It*
'«
1
nl
.34 S
jffS
Jill
Is}
J
'i
i
Jill
i
i
u
ll*
8 -8 M
"JJ
n
1*8
111
]!
iltll
ir
S*|
H
.!*
-!»
ii*?
ill»
llli
•^
1
3 i
B-9
-------
TiW«6
"Oteottal Cheaical-Spttifle ARARl for KB* la Soil
Toxic Substances Control Act (TSCAX
40 CFR, Part 761, Subpart G:
PCB Spill Cleanup policy
1-10 ppm (noarestricted area)
10-25 ppm (restricted area)
25-50 ppm (outdoor electrical substations)
B-10
-------
09
ARARs
RCRA Preparedness and Prevention
(40 CFR 264.30-264.31)
RCRA Contingency Plan and
Emergency Procedures (40 CFR
254.50-254.56)
Virginia Solid Waste Management
Regulations (9 VAC 20-80-10 to
790) December 1988
Relevant and
Appropriate
Relevant and
Appropriate
Relevant and
Appropriate
Waste Transportation
Department of Transportation
(DOT) Rules for Transportation of
Hazardous Materials (49 CFR Parts
171,172, 177, 179)
TSCA-PCB Waste Disposal
Records and Reports (40 CFR
761.202,205,207 to 211 and 218)
VHWMR, Hazardous Waste
Management Regulations (9 VAC
20-60-IQetseq.). July 1, 1991
Virginia Regulations Governing the
Transportation of Hazardous
Material (9 VAC 20-110-10 et seq.).
Applicable
Applicable
Table 7
Action-Specific
| Status _ [_
Applicable
Applicable
Requirement Synopsis
A. COMMON TO ALL ALTERNATIVES
Action to be Taken to Attain ARARs
Page I of 4
This regulation outlines the requirements for safety
equipment and spill control.
This regulation outlines the requirements for safety
equipment and spill control.
this regulation establishes criteria for siting,
design/construction, operation, groundwater
monitoring; and closure of sanitary landfill.
B. OFF-SITE DISPOSAL
Safety and communication equipment will be installed at
the site. Local authorities will be familiarized with the site.
Plans will be developed and implemented during remedial
design. Copies of the plans will be kept on-site.
Below 1 ppm, PCBs will be disposed of in a sanitary
landfill. Above 50 ppm, PCBs will be managed according
to Federal law (TSCA). Between 1 ppm and 50 ppm, PCBs
will be disposed of in facilities with double liners and
double leachate collection systems.
This regulation outlines procedures for the
packaging, labeling, manifesting, and transporting
of hazardous materials.
This regulation establishes the responsibility of
generators, transporters, and disposers of PCB
waste in the handling, transportation, and
management of the waste. Requires a manifest and
recordkeeping.
The Virginia Department of Waste Management
has adopted certain DOT regulations governing the
transport of hazardous materials.
These regulations designate the manner and method
by which hazardous materials shall be loaded,
unloaded, packed, identified, marked, placarded,
stored, and transported.
This regulation will be applicable to any company
contracted to transport hazardous material from the site.
This regulation will be applicable to any company
contacted to transport PCB material from the site.
This regulation will be applicable to any company
contracted to transport hazardous material from the site.
This regulation will be applicable to any company
contracted to transport hazardous material from the site.
-------
Table 7 (continued)
Action-Specific ARARs for Remediation
Page 2 of4
ARARs
Status
Requirement Synopsis
Action to be Taken to Attain ARARs
B. OFF-SITE DISPOSAL (continued)
Discharge
Clean Water Act (40 CFR 100 et
seq.)
Relevant and
Appropriate
The National Pollutant Discharge Elimination
System (NPDES) permit requirements for point
source discharge must be met, including the
NPDES Best Management Practice Program. These
regulations include, but are not limited to,
requirements for compliance with water quality
standards, a discharge monitoring system, and
records maintenance.
Project will meet NPDES permit requirements for point
source discharges.
CO
t3
Virginia Department of
Environmental Quality (DEQ) (9
VAC 25-31-10 to 940) Permit
Regulation [Virginia Pollutant
Discharge Elimination System
(VPDES) and Virginia Pollution
Abatement (VPA) Permit Program],
Adopted March 28-29, 1982
Applicable
The permit governs the discharge of any pollutants,
including sewage, industrial wastes, or other wastes,
into or adjacent to State waters that may alter the
physical, chemical, or biological properties of State
waters, except as authorized pursuant to VPDES or
VPA permit.
The permittee shall comply with all EPA toxic effluent
standards and prohibitions promulgated under the Act
within the time provided by the regulations. The permittee
shall take all reasonable steps not to adversely affect human
health or the environment. Proper operation and
maintenance includes effective plant performance; and
adequate funding, licensed operator staffing and laboratory
process control, including appropriate quality assurance
procedures.
Disposal
TSCA Chemical Waste Landfill (40
CFR 761.75)
Applicable
Covers the basic design, monitoring, and operations
requirements for chemical waste landfill use to
dispose PCB wastes.
Any off-site facility accepting PCB waste from the site
must be properly permitted. Implementation of the
alternative will include consideration of all requirements.
TSCA Disposal Requirements (40
CFR Part 761.60)
Applicable
Requires liquid PCBs at concentrations greater than
500 ppm to be disposed of in an incinerator or by
another technology capable of providing equal
treatment. Liquid at concentrations above 50 ppm
but less than 500 ppm and soils contaminated above
50 ppm may also be disposed of in a chemical
waste landfill.
Alternative development will consider disposal
requirements.
-------
DO
ui
ARARs
Disposal (continued)
RCRA Land Disposal Restrictions
(40 CFR 268, Subpart D)
Virginia Hazardous waste
Management Regulations (9 VAC
20-80- 1 0 et seq.): Hazardous Waste
Permit Program. Part X
Virginia Solid Waste Management
Regulations (9 VAC 20-80-10 et
seq.)
CAA, National Ambient Air Quality
Standards (NAAQS) for Total
Suspended Paniculate (40 CFR
129.105,750)
40 CFR 264, Subpart L
RCRA (40 CFR 264)
CAA, NAAQS 40 CFR 50
Status
Applicable
Applicable
Applicable
Table 7 (continued)
Action-Specific ARARs for Remediation
Pane 3 of'4
Requirement Synopsis
After November 8, 1988, movement of excavated
materials to a new location and placement in or on
land would trigger land disposal restrictions (for
non-CERCLA actions). CERCLA actions became
regulated under this requirement on November 8,
1990.
Covers the basic permitting, application,
monitoring, and reporting requirements for off-site
hazardous waste management facilities.
Virginia program to properly manage solid waste
treatment, storage, or disposal of any solid wastes
containing PCB concentrations between 1.0 ppm
and 50.0 ppm.
Action to be Taken to Attain ARARs
If soil is RCRA waste, the excavated material will be
properly disposed or treated as required by the regulations.
Any off-site facility accepting hazardous waste from the
site must be properly permitted. Implementation of the.
alternative will include consideration of requirements.
1 his regulation may be applied to the disposal of debris off-
site or on-site. PCB concentrations between 1 .0 ppm and
50.0 ppm are restricted to disposal in sanitary landfills or
industrial waste landfills with leachate collection, liners,
and appropriate groundwater monitoring as required in Part
V of the VSWMR.
C. tXCAVATION AND/OR STABILIZATION
Relevant and
Appropriate
To be
Considered
Relevant and
Appropriate
Applicable
This regulation specifies maximum primary and
secondary 24-hour concentrations for paniculate
matter. Fugitive dust emissions from site
excavation activities must be maintained below 1
g/m3 (primary standard).
Provides requirements to design and operate waste
piles.
Requires owner/operator to control wind disposal of
paniculate matter.
Provides air quality standards for paniculate matter,
lead NO2 , SO2, CO, and volatile organic matter
Proper dust suppression methods such as water spray would
be specified when implementing excavation and/or
solidification/stabilization actions.
Performance standards would be specified for compliance.
Fugitive dust emissions will be controlled during
implementation to maintain concentrtaions below these
levels.
Same as above.
-------
Table 7 (continued)
Action-Specific ARARs for Remediation
Page 4 oN
ARAR
Status
Requirement Synopsis
Action to be Taken to Attain ARARs
C. EXCAVATION AND/OR STABILIZATION (continued)
Virginia Air Pollution Control Law,
Code of Virginia Sections (10.1 -
1300 et seq.; Virginia Department of
Air Pollution Control, Regulations
for the Control and Abatement of
Air Pollution (9 VAC 5-10-10)
Applicable
The Virginia Department of Air Pollution Control's
air emissions standards must be met with regard to
the potential release of toxic pollutants subject to
the Department's standards that are released due to
remedial activities at a site. Also, any disturbances
of surface or underlying soil at a site, or treatment
of soil or water must meet the Air Board's standards
for paniculate emissions to the air.
Outlines Virginia Erosion and Sediment Control
Proper dust suppression methods and monitoring will be
required when implementing excavation and/or
solidification actions to prevent paniculate matter from
becoming airborne.
Virginia Erosion and Sediment
Control Law, Code of Virginia
Sections 10.1-560 et seq.; and the
Virginia Erosion and Sediment
Control Handbook (4 VAC 50-30-
10 et seq.)
Applicable
Law Regulations and practices to minimize erosion.
Recommended practices will be followed during
excavation. No "land disturbing" activity, as governed by
the State statute or a local erosion and sediment control
ordinance, may take place until an erosion and sediment
control plan for the activity has been submitted and
approved by the proper authority.
Proper management of storm water programs.
Virginia Stormwater Management
Regulations (1990) (4 VAC 3-20-1
et seq.); Chesapeake Bay
Preservation Act, VA Code Ann. §
10.1-2100 to2116; Chesapeake
Bay Preservation Area Designation
and Management Regulations (9
VAC 10-20-10 to 280)
Applicable
Requires State agencies and local Stormwater
management programs to maintain post-
development runoff characteristics; controls non-
point source pollution, establishes acceptable
administrative procedures; requires stormawater
management programs with erosion and sediment
control, and other land development-related
programs; and reviews and evaluates local
management programs.
-------
APPENDIX C
GLOSSARY
-------
-------
Glossary of Terms
Aquifer: A saturated, permeable geologic formation or structure that is capable of yielding water in usable quantities
under ordinary hydraulic gradients.
Downgradient: The direction tab groundwater flows similar to "downstream" for surface water.
Endpoints of Concern: Conclusions that can be drawn from an investigation.
Fate and Transport: Includes the tendency for a chemical to migrate through the enviroinment and the degree to
Feasibility Study fFSV Report that summarizes the devlopment and analysis of remedial alternatives considered for
the cleanup of CERCLA sites.
Groundwater: The supply of fresh water found beneath the Earth's surface in the interstices between soil grains, in
fractures, or in porous formations.
Leachate: Water that collects contaminants as it trickles through wastes, pesticides or fertilizers. Leaching may
occur in farming areas, feedlots, and landfills, and may resukt in hazardous substances entering surface water,
groundwater or soil.
Receptors: Any living organism or environmental medium which is exposed to contaminations from a discharge.
Remedial Action: Implementation of plans and specifications, developed as part of the design, to remediatea site.
Remedial Investigation (RD: The RI is prepared to report the typem extentm and potential for transport of
constituents of potential concer at a hazardous watse site, and directs the types of cleanup options that are developed
in the FS.
Semi-volatiles: Compounds that do not readily volatilize at standard temoerature and pressure. Compunds that are
amenable to analysis by extraction if the sample with an organic solvent
Target Analvte List: A standard list of metals to analyze in samples.
*
Volatilization: To evaporate or cause to evaporate.
C-10
-------
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