NCD079044426_19950901_General Electric Co. Shepherd Farm_FRBCERCLA ROD_Record of Decision-OCR

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RECEIVED
SEP 2 0 1995 GENERAL ELECTRIC/SHEPHERD FARl\'.[
. NATIONAL PRIORITIES LIST SITE -SUfERFUNDSECTION
EAST FLAT ROCK, HENDERSON COUNTY
NORTH CAROLINA
RECORD OF DECISION '
REGION IV
ATLANTA, GEORGIA
SEPTEMBER 1995
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Record of Decision
GE/Shepherd Farm NPL Site
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DECLARATION
FOR THE
RECORD OF DECISION
SITE NAME AND LOCATION
General Electric/Shepherd Farm Site
East Flat Rock, Henderson County, North Carolina
STATEMENT OF BASIS AND PURPOSE
September 1995
F
This decision document presents the selected remedial action for the General Electric/Shepherd
Farm Site in East Flat Rock, Henderson County, North Carolina, chosen in accordance with the
Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA),
as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA) and, to the
extent practicable, the National Contingency Plan (NCP). This decision is based on the
administrative record file for this Site.
The State of North Carolina concurs with the selected remedy.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this Site, if not addressed by
implementing the response action selected in this Record of Decision, may present an imminent
and substantial endangerment to public health, welfare, or the environment.
DESCRIPTION OF THE SELECTED REMEDY
This remedy addresses the principle threats posed by this Site. The major threats are the
co.ntaminated groundwater emanating from beneath the Site and the surficial contaminated soil.
The major components of the selected remedy include:·
GROUNDWATER
Extraction of groundwater from the GE and Shepherd Farm Subsites that is
contaminated above Maximum Contaminant Levels or the North Carolina
Groundwater Standards, whichever are more protective for each particular
contaminant;
Onsite treatment of the extracted groundwater vi:r-air stripping and carbon
adsorption;
In-situ bioremediation;
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Record of Decision September 1995 GE/Shepherd Fann NPL Site
SOIL
Discharge of treated groundwater to Bat Fork Creek; and
Continued analytical monitoring for contaminants in groundwater and surface
water.
She_pherd Farm Subsite
Excavation of the top foot of soils contaminated above the performance sta1_15lards;
Transportation of excavated soils to the dry sludge impoundment area on the GE property;
Backfilling, grading, and revegatafion of excavated areas.
GE Subsite
Placement of an impermeable cap on the areas where the soil is contaminated above the performance standards;
Continuous maintenance of the cap;
Usage restrictions on the capped areas.
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. This remedy utilizes permanent solutions and altepiative treatment technology to the maximum extent practicable, and satisfies the statutory preference for remedies that employ treatment that reduces toxicity, mobility, or volume as a principal element. Since this remedy may result in hazardous substances remaining onsite above health based levels, a review will be conducted within five years after commencement of remedial action to ensure that the remedy continues to provide adequate protection of human health and the environment.
Richard M. Green
Associate Director
Date
I Waste Management Division
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Record of Decision September 1995 GE/Shepherd Fann NPL Site
DECISION SUMMARY
I. SITE NAME, LOCATION AND DESCRIPTION
A. Introduction
The. General Electric/Shepherd Fann Site (hereinafter referred to as the "the Site") consists of three non-contiguous disposal areas in East Flat Rock, Henderson County, North Carolina. These disposal areas (subsites) are known as the GE property, the Shepherd Fann property, and the Seldon Clark property (see Figure 1). ·
B. Site Description
The GE subsite is located at the southeastern comer of Spartanburg Highway (U.S. 176) and Tabor Road (S.R. 1809) in East Flat Rock, Henderson County, North Carolina (see Figure 2). Geographically, the center of the subsite is located at approximately 35°16·25·_ N latitude and
82°24'10" W longitude according to the Hendersonville, North Carolina, USGS 7.5 minute topographic map. This slightly hilly, approximately 50-acre subsite is bounded on the west by Spartanburg Highway, on the north by Tabor Road, and on the east by Bat Fork Creek. The southern boundary is a fenceline south, east, and west of the recreational facility. General Electric also owns the plot of land located southwest of Spartanburg Highway, south of Bat Fork Creek, between the curved railroad tracks and the highway.
The Shepherd Farm subsite is located on Roper Road, approximately 1200 feet west of Spartanburg Highway and 2500 feet southwest of the GE subsite (see Figure 1). Geographically,
the center of the subsite is located at 35°16'10" N latitude and 82°25'10" W longitude according to the Hendersonville, North Carolina; USGS 7.5 minute topographic map. This hilly, approximately 31-acre subsite is bounded on the north by Roper Road, on the north-northwest
by the Seldon Hill Farm, and on the west by Bat Fork Creek (see Figure 3).
The Seldon Clark subsite is located at the northeastern comer of the Spartanburg Highway and Tabor Road intersection (see Figure 2-1). Geographically, the center of the subsite is located at 35°16'35" N latitude and 82°25'00" W longitude according to the Hendersonville, North Carolina, USGS 7.5 minute topographic map. This approximately 1-acre field is bounded on the west by Spartanburg Highway, on the south by Tabor Road, on the east by Jones Street, and on the north by Second Avenue (see Figure 4).
GE Subsite
The GE facility includes two major building structures: the manufacturing plant (350 feet· by 700
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SITE LOCATION MAP
GE/SHEPHERD FARM PROPERTY
EAST FLAT ROCK, NORTH CAROLINA
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-. SHEPHERD FARM SUBSITE FEATURES MAP
f-----------------------l FIGURE " 3 &EPA
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GE/SHEPHERD FARM PROPERTY
EAST FLAT ROCK, NORTH CAROLINA
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SELDON CLARK SUBSITE FEATURES MAP
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GE/SHEPHERD FARM PROPERTY
EAST FLAT ROCK, NORTH CAROLINA
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Record of Decision September 199S GE/Shepherd Farm NPL Site
feet) and the finished stock warehouse (700 feet by 300 feet). The buildings are separated by
paved parking areas and grassy lawns. The two buildings are situated on a relatively flat liilltop, while the rest of the property is on a hillslope. A tall, barbed-wire, chain-link fence surrounds
the entire property with the exception of the Jandspreading plots (described below) and the front of the facility where parking Jots and manicured lawns exist. . A guard is on duty at all times to keep unauthorized personnel out of the plant and facility grounds.
East of the plant is Demonstration Street, a paved, relatively flat strip of land. Along this area,
lighting fixture displays demonstrate the product line at GE. Several support facilities are located along or near Demonstration Street, including a fork lift shop, a fabricating shop, a reclamation yard, a boiler house, a chlorine building, a drum storage area, an outside vendor (OV) storage area, and other fixtures and structures· such as water tanks and pumps, cryogenic
tanks, gasoline pumps, and storage bins. A closed 0.5-acre landfill (Landfill A) is now paved over by this street.
East of Demonstration Street, beyond the paved Jots, are approximately 26 acres of
Iandspreading plots which are blanketed by vegetation and slope eastward downhill toward Bat Fork Creek. Southeast of Demonstration Street, beyond the drum storage area, is a dry, 3-acre, inactive sludge impoundment which currently has a thick cover of vegetation. Southeast of the finished stock warehouse is a large (5-acre), active, wastewater treatment pond. East of the large wastewater treatment pond is a small (I-acre), active, landfill area where construction debris and excavated soils have been deposited or stored. Southwest of the finished stock warehouse is a grassy lawn area which was also previously used as a landspreading plot.
The area south of Bat Fork Creek also belongs to GE and includes a small (1-acre), active,
wastewater treatment pond, a recreational area with an adjacent playground which was also formerly used as a Iandspreading plot, and a closed 1-acre landfill (Landfill B), parts of which are currently paved over by a driveway leading to the recreation facility.
The unfenced Shepherd Farm property, formerly used for disposal of wastes from the GE facility, is currently a sloping wooded area used for residential purposes. Mr. Shepherd, the owner and operator of the now defunct disposal company, still maintains his residence on this property. In addition, a 22-acre manufactured homes community (Spring Haven) consisting of 125 Jots (most with homes on them) and a community center are present on the southern portion of the subsite. A small unnamed intermittent creek runs through the middle of the subsite before
discharging into Bat Fork Creek.
The unfenced Seldon Clark property, formerly used for landfilling of wastes from the GE facility, is presently a grass-covered field which slopes towards iis eastern boundary, Jones Street. The only facility located on the property is a small run-dowll_ shack which was formerly used as a junk/antique shop.
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Record of Decision September 1995 GE/Shepherd Farm NPL Site
C. DEMOGRAPHY
The Site is located in Henderson County, North Carolina, which had a 1990 census population of 69,285. The town of Hendersonville (the County Seat), the center of which is located approximately 3.5 miles northwest of the site, had a 1990 census population of about 7,300. The county population is about 79% white and 20% black, but in the GE Site vicinity, the distribution is about 96 % white and 2 % black.
Based upon a house count from USGS topographic maps, the population within 1 mile of tl}e GE and Seldon Clark subsites (excluding the approximate 1,100 GE plant employees) is estimated
to be 1,010. The nearest residence is adjacent to the southeast property boundary.
The Spring Haven Community at the Shepherd Farm subsite is a quality development of 90 homes of which approximately two-thirds are occupied year-round. Each unit has one or two persons and the average age is 67. Children are not permitted to live in the development but are present occasionally as visitors. Several of the Spring Haven units are located within the subsite disposal area while most of the other units are located within 500 feet. Four other residences on the south side of Roper Road (three at the Seldon Hill Farm and one at the Shepherd Farm) are also within 500 feet of the subsite disposal area. Based upon a house count from USGS topographic maps, the population within 1 mile of the Shepherd Farm property is estimated to be 1,044.
D. SURROUNDING LAND/WATER USE
The principal land use in the immediate vicinity of the GE and Seldon Clark subsites is residential. Some commercial and light industrial uses occur along Spartanburg Highway, however, and a large plant is on the north side of Tabor Road, across from the GE plant and east of the Seldon Clark property. A large power substation also adjoins the southeast boundary
of the GE property. Open spaces surrounding the subsites are generally undeveloped or farmed land. Orchards are pro~inent to the northeast of the subsites.
The Shepherd Farm subsite is located in a rural/agricultural area where land use is principally
residential, forest, or farmland. The nearest commercial and industrial activity is along Spartanburg Highway, about 2000 feet to the north and east (ATSDR, 1993).
Land is lightly developed along Bat Fork Creek, both upstream and downstream of the Site, and also along Mud Creek into which Bat Fork Creek discharges approximately 6 miles downstream of the GE subsite. Approximately 90 % of the land along Bat Fork Creek is used for agriculture and the remaining 10 % supports urbanized land uses.
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Record of Decision September 1995
GE/Shepherd Farm NPL Site F ----·· Major natural resources in the area include surface waters (including some wetlands) and
groundwater. While .irrigation of agricultural lands along Bat Fork Creek is unlikely due to the
relatively low volume of flow, residents have reportedly used the creek for watering gardens.
In addition, some livestock are likely to obtain water from the stream.
While the steep banks, dense undergrowth, and narrow width of Bat Fork Creek may limit its
utility for recreational fishing, some recreational fishing in this creek has been reported by
residents. Bat _Fork Creek flows into Mud Creek (also used for recreational fishing) which in
turn flows ·into the French Broad River. The French Broad River is used for recreational
fishing, swimming, and boating. However, there are no public water intakes along any portion
of the surface waters downstream of the GE subsite (ATSDR, 1993).
The Hendersonville public water system obtains its raw water from three surface water intakes
which are outside the watersheds possibly affected by the GE site. The GE facility has been -
connected to this public water system since it began operations. In addition, the majority of the .
residepts within a 4-mile radius of the site are also connected to this system. Many homes and
businesses near the site have relied on private wells ( drilled in the shallow aquifer and averaging
about 120 feet deep) for potable water in the past, and some still rely on private wells, but
increasing numbers are being connected to the public system. The GE facility has provided
bottled water to many residents in the vicinity of both the GE subsite and the Shepherd Farm
subsite, and has paid for some connections to the public water system. ·
At the Shepherd Farm subsite, the Spring Haven development has always been connected to the
public water system. The four residents at the Seldon Hill Farm and Shepherd Farm once relied
on private wells for potable water, but are now connected to the public water system.
E. TOPOGRAPHY
The GE Site is located within the Blue Ridge Physiographic Province of the Appalachian
Highlands in the southern Appalachian Mountains. Topography in the area is characterized as
rugged with large hills and rounded mountains, and steep slopes and narrow valleys, but also
with some flat areas in a few small valleys. The Asheville-Hendersonville area is characterized
by a central plateau (the Asheville Plateau) with moderate relief of 500 to 600 feet, surrounded
on all sides by mountains. Elevation of the Asheville Plateau is approximately 2200 feet above
mean sea level (ams!) (NUS, 1991a). ·
The area around the Site consists of gently rolling hills with elevations at about 2100 to 2500
feet amsl. The slope at the GE subsite is generally to the southeast at about 2 percent. The
slope at the Seldon Clark subsite is generally to the northeast at about 4 percent. The slope at
the Shepherd Farm subsite is generally to the northwest at about lQ percent.
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Record of Decision September 1995 GE/Shepherd Farm NPL Site
F. CLIMATE
The climate of the region is humid-continental. Average monthly temperatures range from 41° Fin January to 77° Fin July (Wallingford, 1989). Mean annual precipitation is 38 inches and mean annual lake evaporation is 34 inches. Mean maximum 24-hour rainfall is 3. 7 inches (NUS, 1991a).
G. GEOLOGY
Most soils in the Blue Ridge Province are residual soils derived from weathering C of the underlying bedrock. These soils may be shallow to deep and are typically clayey, although locally they may be coarse-grained. Other soils are derived from alluvium along the floodplains of major streams.
Based on several borings performed at the GE subsite, the soils at the site can generally be described as brown, micaceous, sandy silt near the surface, grading downward to loose firm, red-brown and dark brown, micaceous silty medium to coarse sand. The thickness of the residual soil at the GE subsite ranged from less than 1 foot to 88 feet. The boundary between soil and rock is a transition zone of very dense, partially weathered rock. The partially weathered rock (PWR) at the GE subsite is generally between 2 and 15 feet thick.
H. HYDROGEOLOGY
The shallow groundwater surface in the Blue Ridge Province generally occurs within the residual and alluvial soils. Water occurs in the pore spaces of these soils and the PWR, within the relict fractures of the PWR, and within the fractures and secondary openings of the underlying
bedrock. Although the soil/PWR zone (hereinafter referred to as the "porous media" zone), and the bedrock zone (hereinafter referred to as the "fractured media" zone) are sometimes referred to as different aquifers, they actually comprise one shallow unconfined aquifer since the two zones are hydraulically connected as evidenced by the lack of both a confining zone and significant head difference between the two zones.
Groundwater flow in the Blue Ridge Province generally follows the topography. Recharge occurs from infiltration of precipitation on the hill and mountain slopes, while discharge generally occurs at the streams and springs. The groundwater surface at the site has been observed in monitor wells at depths r.µiging from 3 to 29 feet below ground surface.
I. HYDROLOGY
The surface water features potentially affected by the GE and Seldo~ Clark subsites include Bat Fork Creek and Mud Creek. The surface water features potentially affected by the Shepherd
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Record of Decision September 1995 GE/Shepherd Fann NPL Site
Fann subsite include the unnamed intermittent creek running through the subsite and into Bat · Fork Creek and Mud Creek. These surface waters have been classified as "Class C" by the State, which is the basic water quality classification for all surface waters in the State of North
Carolipa, and protects freshwaters for secondary recreation, fishing, and aquatic life.
Runoff from all three subsites discharges into Bat Fork Creek. At the Shepherd Fann subsite,
runoff also discharges into the unnamed tributary which then discharges into Bat Fork Creek
approximately 400 feet to the northwest. At the GE facility, a natural spring which also
discharges into Bat Fork Creek is located in a swampy area between Bat Fork Creek and the
easternmost landspreading plots. In addition, GE has an NPDES permit to discharge ·treated
industrial effluent into Bat Fork Creek from the GE facility surface impoundments.
Bat Fork Creek is a perennial surface water body which, from visual observation, appears to be about 10 feet wide and less than 1 foot deep at the site under normal flow conditions. The
average gradient of Bat Fork Creek at the site is approximately 24 feet per mile. The stream
lies within the French Broad River basin which is part of the Tennessee River Valley drainage
system.
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES
A. Site History
From 1955 to present, the GE facility has been used to develop, design, and manufacture complete high-intensity-discharge luminaire systems, which consists of the assembly of optical components, ballasts, mountings, and high mast lowering devices. The luminaire · systems
produced at the facility use several light sources including sodium and mercury. These lighting
systems have many uses which include the illumination of roadways, sports arenas and related
buildings and/or parking lots, indoor industrial and/or commercial complexes, and hazardous or
dangerous location applications.
Operations at the facility are comprised of several manufacturing processes. Raw aluminum is smelted and die-cast into molds of light fixture housings. Strip aluminum is machined by a spin
and die process into reflectors that are attached to the housings. These reflectors are finished
in a metal finishing, polishing, or coating process to yield a highly machined, polished or satin
surface, as desired.
From about 1955 until 1975, GE also manufactured "constant-current" transformers at this
facility. These transformers were filled with PCB-containing oil, which were delivered to the
facility in railroad tank cars (NUS, 1991a). GE has reported that PCBs are no longer used in their product line (ATSDR, 1993). _ .
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Record of Decision
GE/Shepherd Farm NPL Site
September 1995
---Prior to GE's purchase of the property in 1955, the GE subsite was used as an apple orchard.
Waste streams generated by GE's facility from the beginning of plant operations have included
construction wastes, buffing compound, epoxy compound, phenolic residue, paint sludges, PCB
capacitors, solvents, transformer oil, electrical insulators/capacitors,. waste acids, dye cast mold
released hydrocarbons, heavy petroleum greases, and varnish residues. These waste streams
contain many VOCs, heavy metals, acids, and PCBs. Current waste streams include solvents,
cadmium-contaminated baghouse dust, waste oils, and lab packs.
Landfill A received waste generated by the facility between 1955 and the 1960s. No info~ation
is available concerning the types of wastes, · but it is assumed that the wastes are from the
manufacturing process utilized during this time of operation. Landfill B is believed to have been
operated during the 1970s. These unregulated practices of the 1950s and the 1960s were ceased
by GE with the promulgation of state and federal legislation to control pollution to the
environment during the 1970s. As these two former landfills have been partially paved over,
there is no physical evidence of waste at the landfill locations.
Wastewater generated as a result of plant process, contains metals and solvents typically used
during lighting system manufacture. GE implemented a wastewater treatment facility in the mid-
1970s consisting of a lime treatment system to adjust the pH of treated waters prior to surface
water discharge. They also constructed the two wastewater treatment ponds described
previously. The unlined ponds were constructed of native clay and are approximately 10 feet
deep. The larger pond has a controlled exit valve at its discharge point to the smaller pond.
As part of the waste treatment process, wet and dry sludges generated in the wastewater
· treatment facility were landspread on several plots surrounding the facility buildings between
1977 and 1980. These landspreading plots, totaling 26 acres, were delineated for disposal of
wet and dry sludges that contained water, lime, and about 0.07 to 2.85 percent nickel typically
used in plant processes.
From 1955 until 1975, GE also generated a substantial quantity of PCB wastes as a result of
transformer production. Disposal of these wastes prior to 1980 is not well documented, but in
1984, PCB wastes were sent to Emelle, Alabama, for disposal.
Underground storage tanks (USTs) at eighteen locations have been used by GE in the past to
store fuels, liquid supplies (paints and varnishes), and liquid wastes. All of these USTs are
reported by GE to have been removed by March 1991, and all liquid storage is now performed
in above ground storage tanks and drums.
From approximately 1957 to 1970, GE wastes were also intermittently deposited at the Shepherd
Farm property where it was dumped, burned, and bulldozed in ~ .approximate 3-acre area
onsite. At the time of the dumping, the only other use of the property was for the Shepherd's
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Record of Decision
GE/Shepherd Farm NPL Site
September 1995
residence. The Spring Haven community was later constructed over part of the dumping area.
Most of the waste was reportedly deposited into an old dry pond or ravine approximately 800
· feet southwest of the Shepherd residence. When the. path leading to the ravine was iced,
however, the waste was placed along the path. According to Mr. Shepherd, the waste consisted
of cardboard, wood, office paper, and buffing compound. Occasionally, electrical "insulators"
were taken to the site and broken to salvage copper. These might have been capacitors as
insulators do not contain copper.
During the 1960s and early 1970s, GE wastes· were also dumped in an approximate 0.3-acre
ravine on the Seldon Clark property. GE reported that the property was used for the clisposal
of construction rubble only, but according to Mr. Clark, the ravine was also filled in with drums
of aluminum paint and drums of cleaning fluid from dye-casting machinery. Old transformers
are also reported to have been deposited in the ravine. The suspected disposal area is located
in the southwestern half of the property but there is presently no physical evidence of a landfill.
B. PREVIOUS INVESTIGATIONS
Several recent sampling investigations have been conducted at the site, especially at the GE
facility. The quality of the data collected during the GE-conducted events, however, is
unknown. These studies have included monitor well installation and groundwater sampling, soil
sampling, surface water/sediment sampling, and offsite private well sampling.
Figure 5 shows the locations of all the permanent monitor wells installed at the GE subsite.
Figure 6 shows the locations of the private wells sampled.
From 1986 through 1991, GE tasked Law Environmental to conduct sampling investigations of
soil and groundwater around the GE plant site. In 1988 and 1989, EPA conducted Site
Inspections and Investigations into the contamination at the GE facility, Shepherd Farm property,
and the Seldon Clark property. Results of analysis revealed the presence of PCBs in soil and
volatile organic compounds in the groundwater. A groundwater VOC (PCB) concentration map
prepared by GE based on the results of these sampling events is presented in Figure 7.
The results indicate tetrachloroethene is the major contaminant present in groundwater beneath
the site and, as discovered before, the greatest contaminant concentrations are present along the
failed drain line. However, high concentrations of VOCs were also found along the railroad line
southwest of the failed drain line area, indicating that a preferential flow path may be present
along the railroad, or that another source of contamination is present in this area. One possible
source identified in this investigation was an old drainage ditch which existed prior to
construction of the drain line.
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EAST FLAT ROCK, NORTH CAROLINA
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Record of Decision
GE/Shepherd Farm NPL Site September 1995
-----C. PREVIOUS REMEDIATION EFFORTS
GE has conducted or prepared for several remediation and/or removal actions at the GE subsite.
GE reports that all USTs and contaminated soils associated with these USTs have been removed.
GE also reports that contantinated soil associated with the ruptured drain line have been
removed. City water mains have been extended to all areas showing groundwater contantination
based on private well sampling, and GE has paid for connections to these water mains and/or
provided bottled water for all households so desiring such action. Figure 8 shows the areas near
the GE property where residents were offered city water connections. . ,
In 1990, GE also conducted a Phase IIIA Aquifer Characterization and Groundwater Treatment
Study at the GE facility in preparation for performing groundwater remediation. In this study,
a pilot groundwater recovery and treatment system was designed and installed at the GE subsite.
The system consisted of four groundwater recovery wells (RW-1 through RW-4), a 10,000-
gallon equalization tank, an air stripping tower, and associated piping and pumps with discharge
going to Bat Fork Creek. Seven observation wells (MW-38 through MW-44) were also
constructed for measuring water levels during an aquifer performance test. This system is still
in place.
GE is currently testing a system whereby their process wastewater is discharge to the publicly
owned treatment works (POTW) instead of to Bat Fork Creek through the wastewater treatment
ponds.
D. SITE REGULATORY ACTIONS
The GE facility filed Part A of a hazardous waste permit for storage in 1980 under the Resource
Conservation and Recovery Act (RCRA). In March 1982, GE petitioned to have its F006
electroplating sludge delisted as a hazardous waste. By April 1982, EPA issued a preliminary
decision to declare the F006 waste as nonhazardous. The state of North Carolina accepted the
petition and delisted F006 waste in October 1982. In 1984, GE elected to dispose of
accumulated wastes offsite and therefore withdrew the PartA hazardous waste permit application
and related interim status. On September 19, 1988, EPA formally recognized the state-approved
delisting of F006 electroplating sludge as a hazardous waste.
GE has an NPDES permit for the discharge of treated effluent into Bat Fork Creek which
became effective on May 1, 1989. GE also has an air permit issued on February 25, 1988, to
operate several air emission sources or clean air devices.
After the EPA Screening Site Inspections and Listing Site Inspections described above were
completed, the GE, Shepherd Farm, and Seldon Clark properties ~ere proposed for inclusion
on the NPL on February 7, 1992, as the"General Electric/Shepherd Farm Site". The site was
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I t".Q/7EnA GE/SHEPHERD FARM PROPERTY r ~ r-f-\ EAST FLAT ROCK, NORTH CAROLINA
FIGURE-,' 8
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Record of Decision
GE/Shepherd Farm NPL Site
September 1995
finalized on the NPL in December 1994.
EPA sent a notice letter to General Electric in July 1993 offering the opportunity to conduct the
RI/FS. The notice letter also informed the PRP of its potential liability for past and future site
costs. On January 4, 1994, EPA sent notice/request for access letters to Mr. Wayne Dickason,
Mr. Lawrence Ward, and Mr. Shepherd. Ge was also sent a request for access letter.
ill. IDGHLIGHTS OF COMMUNITY PARTICIPATION
Pursuant to CERCLA Sections 113(k)(2)(B)(i-v) and 117, the RI/FS Report and the Proposed
Plan for the GE/Shepherd Farm Site were released to the public for comment on July 24, 1995.
These documents were made available to the public in the administrative record located in an
information repository maintained at the EPA Docket Room in Region IV and at the Henderson
County Public Library in Hendersonville, North Carolina.
The notice of the availability of these documents was published in the Henderson Times News
and the Asheville Citizen on July 24, 1995. A public comment period on the documents was
held from July 24, 1995 to September 22, 1995. .A copy of the notice was mailed to the site
mailing list which contains names of community members and interested parties. In addition,
a public meeting was held on August 3, 1995. At this meeting, representatives from EPA
answered questions about the site and the remedial alternatives under consideration. Meetings
with city and county officials were also held.
Other community relations activities included:
*
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*
Established an information repository
Prepared an extensive mailing list
Developed a community relations plan
Issuance of a Fact Sheet on the RI/FS process in August 1994.
Conducted a Superfund Workshop for the public in September 1994.
* Issuance of a Fact Sheet on the RI results in June 1995.
* Issuance of a Fact Sheet on the Proposed Plan in Ju,!y 1995.
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Record of Decision
GE/Shepherd Farm NPL Site
September 1995
IV. SCOPE AND ROLE OF RESPONSE ACTION WITHIN SITE STRATEGY
As with many Superfund Sites, the GE/Shepherd Farm Site is very. complex. However, all
aspects of the cleanup will be addressed concurrently and the site has not been divided into
phases or "operable units".
This ROD will present a final remedial action for the entire site.
V. SUMMARY OF SITE CHARACTERISTICS · ..
During the Remedial Investigation, surface and subsurface soil, sediment and surface water
samples were collected, temporary monitor wells were installed and sampled and permanent
monitor and potable wells were sampled. For more details about sample results, please refer
to the Remedial Investigation Report.
A. Soil Sampling
Thirty four surface soil samples and 41 subsurface soil samples were collected during this
investigation. The sampling results will be summarized by each subsite.
GE Subsite
Twenty surface soil samples and 21 subsurface soil samples were collected from the_
landspreading areas, along the drain line and former ditch, along the railroad track and from the
present and former landfills. Also, one replicate and two co-located samples were collected.
Landspreading Areas
Twenty four samples were collected from 11 locations in landspreading areas A, B, C and D.
The locations are indicated on Figure 9.
A single volatile organic compound was detected in the landspreading areas. The presumptive
evidence of acetone was detected in samples 4-SLA, 4-SLB and 11-SLB at concentrations of
18N ug/kg, 17N ug/kg and 17N ug/kg, respectively.
PCB's were detected in one sample. Sample 11-SLA, the surface soil sample from
landspreading area D, contained 60 ug/kg of PCB-1260. Pesticides were detected in all of the
surface soil samples collected from the land spreading areas, except sample 11-SLA. Among
these were dieldrin, 4,4'-DDT, 4,4'-DDE, and toxaphene. -.
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Record of Decision September 1995
GE/Shepherd Farm NPL Site
----. A variety of metals was detected in the soil samples including barium, chromium, copper, lead,
zinc, mercury and manganese.
Landfills
Tirree landfills, designated A, B and C, exist on site. Eight samples were collected from six
locations in the three landfills. One grab surface soil and 2 grab subsurface soil samples were
collected from landfill A. One composite surface and one grab subsurface soil sample were
collected from landfill B and from landfill C.
Samples 13-SLA and 13-SLC collected from iandfill A contained volatile organic compounds.
Sample 13-SLA contained 27 ug/kg of 1,2-dichloroethene, 21 ug/kg of chlorobenzene and 23N
ug/kg of acetone. Sample 13-SLC contained 16,000 ug/kg of tetrachloroethene, 1,600J ug/kg
of ethyl benzene and 4,400 ug/kg of xylenes. Samples collected froni landfills B and C
contained no detectable volatile organic compounds.
Sample 18-SLA, landfill C, contained 180J ug/kg of fluoranthene, 130J ug/kg of pyrene, 90JN
of pentachlorobiphenyl. Sample 18-SLB contained naphthalene, acenaphthene, dibenzofuran,
fluorene,phenanthrene, fluoranthene, pyrene, benzo(A)anthracene, chrysene, benzo(B and/or
K)fluoranthene, benzo-A-pyrene·, indeno(l,2,3-CD) pyrene, dibenzo(A,H)anthracene,
benzo(GIIl)perylene and carbazole at concentrations up to 1,700J ug/kg.
Pesticides were not. detected in any of the landfill samples. PCB's were detected in all the
landfill samples. PCB-1242 was detected in sample 12-SLA, landfill B, at a concentration of
22,000C ug/kg. PCB-1254 was detected in all the samples at concentrations up to 36,000C
ug/kg. PCB-1248 was detected in samples 512-SLA and 12-SLB, landfill B, and 18-SLA,
landfill C, at concentrations up to 9,700C ug/kg. PCBcl260 was detected in all the samples at
concentrations up to 120,000C ug/kg in sample 13-SLC, landfill A.
A variety of metals was detected in the soil samples including barium, chromium, copper, lead,
zinc, mercury and manganese.
Drain Line/Fonner Ditch
Four soil samples were collected from two locations beneath the drain line/former ditch.
Location 14 was off the east comer of the main plant and location 15 was due west of the OV
Stores building.
The presumptive evidence of a single volatile organic compound, acetone, was detected in
sample 15-SLB. _ .
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Record of Decision September 1995 GE/Shepherd Farm NPL Site
Pesticides were not detected in any of the samples. Sample 14-SLA and 14-SLB contained PCB-· 1254 at concentrations of 240 ug/kg and 160 ug/kg, PCB 1248 at concentrations of 150 ug/kg and 96 ug/kg, and PCB-1260 at concentrations of 540 ug/kg and 370 ug/kg, respectively.
Sample 15-SLA contained PCB-1260 at a concentration of 64 ug/kg. Sample 15-SLB contained
no detectable PCB's.
A variety of metals was detected in the soil samples including barium, chromium, copper, lead,
zinc, mercury and manganese.
Railroad Track
Two subsurface soil samples were collected along the railroad track. Location 16 was off the
east corner of the main plant and location 17 was west of the warehouse building. The samples
were collected just below the railroad gravel bed.
No volatile organic compounds were detected.
Pesticides were not detected in either of the samples. Sample 16-SLB contained PCB-1254 at
a concentration of 53 ug/kg and PCB 1248 at a concentration of 46 ug/kg. Sample 17-SLB
contained PCB-1260 at concentration of 58 ug/kg.
A variety of metals was detected in the soil samples including barium, chromium, copper, lead,
zinc, mercury and manganese .
Underground Storage Tank Locations
Three subsurface soil samples (samples 19, 20 and 22) were collected from locations near the
former underground storage tank locations.
No volatile organic compounds were detected. Sample 20-SLD contained l,000JN ug/kg of
hexadecanoic acid and one unidentified compound. Samples 19-SLA and 22-SLD contained no
detectable extractable organic compounds.
Sample 19-SLA contained 6.0 ug/kg of dieldrin, 25 ug/kg of 4,4'-DDT and 21 ug/kg of 4,4'-
DDE. Pesticides were not detected in samples 20-SLD or 22-SLD. PCB's were not detected
in any of the samples.
A variety of metals was detected in the soil samples including barium, chromium, copper, lead,
zinc, mercury and manganese.
Seldon Clark Subsite
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Record of Decision
GE/Shopherd Farm NPL Site
September 1995 --Soil borings were drilled at three locations, as indicated on Figure 10. Locations 30 and 31
were in the fill area on the Seldon Clark property and location 32 is west across Spartanburg
Highway.
Sample 31-SLE (12-14 feet BLS) collected from the fill material contained acetone, methyl ethyl
ketone, 1,2-dichloroethene and methyl hexanone at concentrations of 160 ug/kg, 190 ug/kg, 4J
ug/kg and 30JN ug/kg, respectively. Samples 30-SLF (30-32 feet BLS) and 31-SLF (38-40 feet
BLS) , collected from native soil beneath the fill material, contained no detectable volatile
organic compounds.
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Pesticides were detected in samples 31-SLE, 32-SLB and 32-SLC. Sample 31-SLE contained
4,4'-DDT, 4,4'-DDE and 4,4'--DDD at concentrations of 11 ug/kg, 15 ug/kg and 76 ug/kg,
respectively. Sample 32-SLB contained 4,4'-DDD, gamma-chlordane and alpha-chlordane at
concentrations of 18 ug/kg, 15 ug/kg and 15 ug/kg, respectively. Sample 32-SLC contained 4.3
ug/kg of 4,4'-DDT, 8.8 ug/kg of 4,4'DDE and 3.3J ug/kg of 4,4'-DDD.
PCB's were detected in two samples. -Sample 32-SLA contained 220 ug/kg of PCB-1254, 420
ug/kg of PCB-1248 and 36 ug/kg of PCB-1260. Sample 32-SLB contained 86 ug/kg of PCB-
1254.
A variety of metals was detected in the soil samples including: barium, chromium, copper, lead,
zinc, mercury and manganese.
Shepherd Fann Subsite
Thirteen composite surface soil samples and 15 subsurface grab samples were collected from the
Shepherd Farm property. The locations are indicated on Figure 11.
Eight surface and eight subsurface samples were collected from yards in the Spring Haven
development. These locations are designated 50 through 55. The three samples collected from
location 50 are considered control samples for the study. The fill area located behind and west
of the Shepherd house and north of the Spring Haven development was divided into five areas.
These locations are designated 56 through 60. One composite surface soil sample and a grab
subsurface soil sample were collected from the center of each area at a depth of three feet to
four feet BLS. Also, grab subsurface soil samples were collected from locations 57 and 59 at
a depth of six feet to eight feet BLS.
Volatile organic compounds were detected in two samples. Sample 53-SLB contained 6J ug/kg
of tetrachloroethene and 2J ug/kg of xylenes. Sample 56-SLA contained 2j ug/kg of
tetrachloroethene.
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Record of Decision September 1995
GE/Shepherd Fann NPL Site
Extractable organic compounds were detected in eight surface soil samples and one subsurface
soil sample.
Lindane was detected in sample 56-SLA at a concentration of 110 ug/kg. 4,4'-DDT was
detected in samples 55-SLA, 55-SLB and 57-SLB at concentrations ranging up to 130 ug/kg.
4,4'DDE was detected in samples 55-SLB and 60-SLA at concentrations up to 130 ug/kg.
PCB' s were detected in nine surface soil samples and three subsurface soil samples.
Concentrations of total PCB's which exceeded 5,000 ug/kg were detected in samples 53:SLA,
56-SLA, 57-SLA and 58-SLA. Total PCB's concentrations which exceeded 1,000 ug/kg ( but
less than 5,000 ug/kg) were detected in samples 51-SLA, 51-SLB, 54-SLA and 60-SLA.
A variety of metals was detected in the soil samples including barium, chromium, copper, lead,
zinc, mercury and manganese.
Sample 59-SLC was analyzed for eleven TCLP metals including silver, arsenic, barium,
cadmium, chromium, lead, selenium, nickel, antimony, beryllium and thallium. Barium, the
only contaminant detected, was found at 0.39 mg/I, which is below the TC Rule regulatory level
of 100 mg/I.
B. Surface Water and Sediment Sampling
Thirteen surface water and sediment samples were collected from 12 locations during this
investigation. Six samples, locations one through six, were collected from the GE property.
Location 4 is a spring which flows into the adjacent creek. One sample was collected from the
Seldon Clark property, location 30; and six samples were collected from the Shepherd Farm
property, locations 50 through 54. Sample location 452 is a duplicate of sample location 52.
The locations are indicated on Figures 12, 13 and 14, respectively.
Surface Water
Tetrachloroethene was detected in all six samples collected from the GE property and from
samples 51-SW and 54-SW. The concentrations ranged between 0.53 ug/1 and 3.5 ug/1. Sample
4-SW contained 6.Sug/1 of cis-1,2-dichloroethene, 0.71J ug/1 of 1,1,1-trichloroethane and l.9J
ug/1 of trichloroethene. Sample 6-SW contained 7.4J ug/1 of carbondisulfide. Samples 52-SW
and 452-SW contained 3.0J and 3.2J ug/1 of toluene.
No pesticides or PCB's were detected in the surface water samples.
-·· Metals were detected in all of the surface water samples. The SMCL of 50-200 ug/1 of
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Record of Decision September 1995 GE/Shepherd Farm NPL Site
aluminum was exceeded in all the samples collected. The SMCL of 0.3 mg/I of iron was exceeded in all the samples collected. The SMCL of 50 ug/1 of manganese was exceeded in samples 2-SW, 3-SW, 4-SW, 5-SW, 6-SW and 30-SW.
Sediment•
· No volatile organic compounds were detected in the sediment samples. Extractable organic compounds were detected in eight sediment samples. Sample 30-SD contained phenanthrene, fluoranthene, pyrene, chrysene, benzo(B and/or K)fluoranthene, benzo-A-pyrene, indeno(J ,2,3-CD) pyrene, dibenzo(A,H)anthracene and benzo(GHI)perylene. The concentrations ranged between 70J ug/kg and 150J ug/kg. ·
Samples 1-SD and 54-SD contained 4,4'-DDT at concentrations of 6.2 ug/kg and 5.0N ug/kg. Sample 2-SDcontained 7.8 ug/kg of 4,4-'DDE and 5.6 ug/kg of endrin aldehyde.
Six samples contained PCB's. PCB-1248 was detected in samples 2-SD, 3-SD, 5-SD, 6-SD and 51-SD. The concentration~, ranged between 54 ug/kg and 430 ug/kg. Sample 6-SD also contained 85 ug/kg of PCB-1254 and 34J ug/kg of PCB-1260. Sample 30-SD contained 49 ug/kg of PCB-1254. .
A variety of metals was detected in the sediment samples including barium, chromium, copper, lead, zinc, and manganese. No elevated concentrations were detected.
c. Temporary Monitor Well Installation and Samplin2
Nine temporary wells were installed at the locations specified on Figures 15, 16, and 17. Sample 551-TW is a duplicate of sample 51-TW. Location 50 is considered background for the site.
Volatile organic compounds were detected in six samples from five locations. Sample 2-TW contained 0.59J ug/1 of 1,2-dichlorobenzene, 0.80J ug/1 of 1,2,4-trichlorobenzene and 0. 71.J ug/1 of 1,2,3-trichlorobenzene. Sample 30-TW contained. 0.067AJ ug/1 of p-isopropyltoluene. Sample 50-TW contained l.lJ ug/1 of chloroform. Sample 51-TW contained 1. lJ ug/1 of vinyl chloride, l.2J ug/1 of cis-1,2-dichloroethene, 0.98J ug/1 of trichloroethene and 29 ug/1 of tetrachloroethene. Sample 53-TW contained 32 ug/1 of tetrachloroethene.
Extractable organic compounds were detected in one sample. No pesticides or PCB's were detected in the temporary well samples.
Metals were detected in all of the temporary well samples. Sample 30-TW contained 0.28 ug/1
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Record of Decision September 1995 GE/Shepherd Farm NPL Site -· of mercury. The MCL for mercury is 2 ug/1.
D. On Site Permanent Monitor Well Sampling
Twenty four of the existing permanent monitor wells located on the GE property were sampled. Figure 18 indicates their locations.
Volatile organic compounds were detected in 21 of the 24 wells sampled. To facilitate the data presentation and discussion, the compounds cis-1,2-dichloroethene, trichloroethen~ and tetrachloroethene were chosen as indicator compounds. These compounds _were detected. at the greatest frequency in the wells. Cis-1,2-dichloroethene was detected in 18 wells at concentrations between 0.72J ug/1 in well MW-22A to 380J ug/1 in well MW-11. Trichloroethene was detected in 16 wells at concentrations between 0.93J ug/1 in well 22A-MW to 130 ug/1 in well 14-MW. Tetrachloroethene was detected in 20 wells at concentrations between 1.5J ug/1 in well 21-MW and 1,600 ug/1 in well 11-MW.
Concentration isopleth maps for these compounds were developed using an exponential kriging algorithm and Golden Software's SURFER modeling program. These maps visually delineate the horizontal and vertical extent of contamination in the ground water under the site.
The results are presented as Figures 19, 20, and 21.
As indicated on the figures, the area with the highest contamination lies along the drain line/former ditch in the vicinity of wells MW-11, MW-12, MW-12A and MW-12B. The concentration gradient drops gradually toward the northeast, which is the direction of ground water flow, and more abruptly to the northwest and southeast.
Monitor well MW-14 contained high concentrations of all three compounds. This well is east-northeast of the former leaking underground storage tank located between the railroad track and the northwest side of the warehouse.
Two individual compounds detected which merit discussion are benzene and vinyl chloride. Benzene was detected in well 19-MW at a concentration of 2.7J ug/1 and in well 38-MW at a concentration of 0.52J ug/1. Vinyl chloride was detected in wells 4-MW, 14B-MW and 38-MW at concentrations of 2.8J ug/1, 0.69AJ ug/1 and 2.4J ug/1, respectively. Vinyl chloride is a degradation product of tetrachloroethene.
Extractable organic compounds were detected in five samples. Sample I I-MW contained 1. 8J lig/1 of 2-methyl naphthalene, 3.2J ug/1 of 1,2,4-trichlorobenzene, 4.7J ug/1 of naphthalene and 3.3J ug/1 of 2,4-dinitrophenol. Sample 12-MW contained 5. IJ ug/1 of 2-methyl naphthalene, 3.0J ug/1 of 1,2,4-trichlorobenzene, 37J ug/1 of naphthalene, 2.3J ugl! of dibenzofuran, 1. lJ ug/1 of fluorene, l.3J ug/1 of phenanthrene. Sample 12A-MW contained 3.2J ug/1 of 1,2,4-
34
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-400
0
I
0 400
SCALE IN FEET
GE PROPERTY ON SITE MONITOR WELL LOCATIONS
GENERAL ELECTRIC SUPERFUND SITE
EAST FLAT ROCK, NORTH CAROLINA
J
FIGURE 18
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lgi
"' !2
N
• -MONITOR WELL
ND -NOT DETECTED
-30--CONCENTRATIONS µg/L
APPROXIMATE SCALE -. . ... ...
IN FEET
~
M'N-30 •o•
FIGURE 19
TETRACHLOROETHENE, SHALLOW WELLS
GENERAL ELECTRIC SUPERFUND Sl'fE
EAST FLAT ROCK, NORTH CAROLINA
~6EPA [f--------------------'
500.00
250.00
100.00
50.00
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• -MONITOR WELL
ND -NOT DETECTED
-30--CONCENTRATIONS µg/L
APPROXIMATE SCALE
•N I "' "'
IN FEET FIGURE 20
TOTAL voe, SHALLOW WELLS -.
GENERAL ELECTRIC SUPERFUND SITE
EAST FLAT ROCK, NORTH CAROLINA
---
1000.00
500.00
300.00
100.00
50.00
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• -MONITOR WELL
ND -NOT DETECTED
-30--CONCENTRATIONS µg/L
APPROXIMATE SCALE -. ,., ...
IN FEET ·FIGURE 21
TOTAL voe CONCENTRATION, DEEP WELLS
GENERAL ELECTRIC SUPERFUND SITE
EAST FLAT ROCK, NORTH CAROLINA
~9EPA f-----~
1500.00
, 1300.00
1100.00
900.00
700.00
500.00
300.00
100.00
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Record of Decision
GE/Shepherd Farm NPL Site
September 1995
trichlorobenzene, 2.8J ug/1 of naphthalene.
Metals were detected in all of the monitor well samples. Primary MCL's for barium and
beryllium were exceeded in sample 38-MW, which contained 4,000 ug/1 of barium and 15 ug/1
.· ofl:Jeryllium. The MCL's are 2,000 ug/1 and 4 ug/1, respectively. Manganese was detected in
21 samples at concentrations ranging between 4.9 ug/1 in sample 32-MW to 5,000 ug/1 in sample
38-MW. Thirteen samples.contained concentrations above the secondary MCL of 50 ug/1. Iron
was detected in 15 samples. The secondary MCL for iron of 300 ug/1 was exceeded in eight
samples. Mercury was detected in samples 4-MW, 12-MW,14-MW and 35-MW, at a
concentrations ranging between of 0.22 ug/1 and 0.62 ug/1. The MCL for mercury is 2 ug/1.
E. Potable Well Sampling
Eleven potable wells were sampled during this investigation. Figure 22 indicates the well
locations.
Volatile organic compounds were detected in two samples. Sample 83-P contained 1. lJ ug/1 of
tetrachloroethene and sample 91-PW contained 0.58J ug/1 of 1,1,1-trichloroethane. Neither of
these concentrations are above their respective MCL's. No extractable organic compounds were
detected in the potable well samples. No pesticides or PCB's were detected in the potable well
samples.
A variety of metals was detected in all of the potable well samples. Samples 73-PW and 91-PW
contained 24 ug/1 and 19 ug/1 of lead, respectively. Sample 91-PW contained 550 ug/1 of zinc.
The SMCL for zinc is 500 ug/1. Six samples contained aluminum. Samples 83-PW, 15-PW and
43-PW were above 200 ug/1. Samples 73-PW and 91-PW were above 50 ug/1. The SMCL for
aluminum is 50-200 ug/1. The SMCL of 50 ug/1 for manganese was exceeded in samples 2-PW,
15-PW, 6-PW and 43-PW. The SMCL of 0.3 mg/I for iron was exceeded in samples 83-PW,
15-PW, and 6-PW.
Well Survey
In July and August, 1994, EPA mailed out 990 private well/water use surveys to residents living
within a one-mile radius of the GE plant subsite. Approximately 109 or 11 % were returned by
the post office for various reasons (person moved, no forwarding address, post office box
closed, etc.) Of the remaining 881 who received the survey, only 309 residents, or 35 % of
residents who received the survey, completed the questionnaire, and returned it to EPA. Of
those, 224 or 72.5 % were currently receiving city water. Eighty five of those responding to the
survey or 27 .5 % indicated that they were currently using their well for drinking water or other
household purposes. _ .
39
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,-..:
(/)
•.,, "
0------z 52
~ <f
~ & Q:-
POTABLE WELL LOCATIONS
----
l!
Ii! .
0 •
~
Ii!
I 1----------------------.....l FIGURE 22
D! ~EPA
I
GENERAL ELECTRIC SUPERFUND SITE
EAST FLAT ROCK, NORTH CAROLINA
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Record of Decision September 1995 GE/Shepherd Farm NPL Site
G. ECOLOGICAL STIJDY
In November 1994, an ecological study was conducted. A total of 10 sampling locations were selected as shown on Figure 23. Station 101 served as a background station for the unnamed tributary. Stations 103 (upstream of confluence with the unnamed tributary) and 105 (just upstream of the GE subsite) were chosen as background stations on Bat Fork Creek.
At each sampling station, in-situ water chemistry was measured, water and sediment samples were collected, and a Rapid Bioassessment Procedure (RBP) Protocol I (screening meth9d for detecting biological impairment) was conducted. Each RBP included a habitat assessment, physico-chemical characterization, and a benthic macro invertebrate survey. An attempt was also made to collect fish at each station for tissue analysis. The results of the toxicity tests conducted on water and sediment samples are summarized in Tables 1 and 2 respectively. The results of the fish tissue analyses are shown in Table 3. Table 4 summarizes and compares scores for the Habitat Assessments conducted at each sampling station.
VI. SUMMARY OF SITE RISKS
The GE Site is releasing contaminants into the environment. The Basefuie Risk Assessment Report presents the results of a comprehensive risk assessment that addresses the potential threats · to public health and the environment posed by the Site under current and future conditions, . assuming that no remedial actions take place, and that the GE facility would remain an industrial facility.
The Baseline Risk Assessment Report consists of the following sections: identification of chemicals of potential concern; toxicity assessment; human exposure assessment, risk characterization; and environmental assessment. All sections are summarized below.
A. Chemicals of Potential Concern
Data collected during the RI were reviewed and evaluated to determine the chemicals of potential concern at the Site which are most likely to pose risks to the public health. These contaminants were chosen for each environmental media sampled.
The chemicals of potential concern in groundwater are barium, beryllium, manganese, molybdenum, nickel, lead, strontium, .aluminum, vinyl chloride, methylene chloride, 1, 1-dichloroethene, 1,2-dichloroethene,chloroform, 1,2-dichloroethane, bromodichloromethane, 1,2-dichloropropane, trichloroethene, benzene, tetrachloroethene, 1,4-dichlorobenzene, 1,2,4-trimethylbenzene, nitrobenzene, and 2,4-dinitrophenol. _ .
41
liiiiil ---liiiiiil liiiiill -liiiil liiiil iiiilil -- - - - - - --
I• Sampling Station
Approximate Scale
0 500
/
Spring
Haven
Trailer Pk:.
Urmamed Tributary
ldon Oark
iaborRd.
-mt Pond
···•>ii'/".c .. c~e1c
osteTteolznert',·,
Pond . ·· ..
Figure 23 Sampling stations along streams in the vicinity o( General Electric/Shepherd Far.n S~perfund Site, East Flat Rock, North
· Carolina. November 1994.
Table 1 Summary of results of toxicity tests on surface water samples collected from
streams near General Electric, East Flat Rock, NC. November 1994.
Sample Sampling
ID# Location
GE-101-SW Background for Unnamed Tributary
GE-102-SW Unnamed Tributary
GE-103-SW Bat Fork Creek -Spring Haven Trailer Park
GE-104-SW Bat Fork Creek -Shepherd Farm
GE-l05-SW Bat Fork Creek -Background for GE Site
GE-106-SW Bat Fork Creek -Inside GE Site
GE-l07-SW Bat Fork Creek -Downstream of GE Discharge
GE-108-SW Bat Fork Creek -Downstream of Station l07
GE-109-SW Bat Fork Creek -Downstream of GE Site
GE-110-SW Ditch on Seldon Clark Subsite
CONTROL DMW
I -LC50 values cal cu ateo tmm :, mmute readm s. g
2 -Control for samples IOI through 105.
3 -Control for samples 106 through 1 IO.
Ceriodaphnia
7 day Chronic
Adult Average
Su"ival # Young
IO 23.4
IO 24.6
10 37.2
9 37.7
IO 31.2
9 31.2
IO 35.5
9 34.1
IO 32.6
IO 33.7
10 24.62/31.3'
Algae Growth
(mean c:dl density In
nuorometer units)
3.21
2.99
4.08
4.01
3.33
' 4.06
0.63
0.78
2.68
3.00
3.39
Microtox
LCSO'
(% sample)
>100
> 100
>100
>100
>100
>100
>100
>100
>100
> 100
> 100
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iilii -111111 liililil lliiiiiil lliiiiiil Ii& iiiii1 iiiii1 iiiii ---------
Table 2 summary of results of toxicity tests on sediment samples collected from streams
near General Electric, East Flat Rock, NC. November 1994.
Sample Sampling
ID# Location
GE-tot-SD Background for UMamed Tributary
GE-102-SD UMamed Tributary
GE-103-SD Bat Fork Creek -Spring Haven Trailer Parle
GE-104-SD Bat Fork Creek -Shepherd Fann
GE-IOS-SD Bat Fork Cneek -Background for GE Site
GE-106-SD Bat fork Cneek -Inside GE Site
GE-107-SD Bat Fork Creek -Downstream of GE Discharge
GE-108-SD Bat Fork Creek -Downstream of Station I 07
GE-109-SD Bat Fork Cneek -Downstream of GE Site
GE-110-SD Ditch on Seldon Clark Subsite
CONTl{OL DMW
I -LC50 values ca culatea trom :, nunute readm s. g
2 -Control for samples 101 through JOS.
3 -Control for samples 106 through 110.
Ceriodaphania
7 day Chronic
Adult Average
Su"ival #Young
8 22.2
to 28.6
to 16.7
10 22.S
8 22.6
10 37.9
9 33.6
10 30; I
10 26.6
9 29.0
10 24.52/32.3'
. .
Lettuce Seed
Germination
(% gennlna~on)
26 l
86
88 ., .
'
63
6S
' 86
73
90
83
49
80
Microtox
LCS02
(%Sample)
> 100
>100
>100
83.3
>100
>100
>100
>100
> 100
>100
>100
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Table 3 Results of fish tissue analyses, GE/Shepherd Farm Superfund Site, Eas!,Elat·Rock, ·
North Carolina.
Pesticides Metals
Sampling (mg/kg) (mg/kg)
Station DDE PCB-1248 PCB-1016 Copper Zinc
102 o.osou 0.321 0.030 1.7 34
103 o.osou .. _··•-·····-•·.)().49·••<·•·•-•··· 0.45U 0.88 39
104 0.051U :::,.:: /0;49 ·r·· 0.45U 0.91 39
105 0.18 I ii:J:6· >> I.SU 0.95 39
106 0.12 ·-·•--•-<1.4C I.OU 1.2 42
107 0.061 . L4C I.OU LOU 26
108 0.093 1.9C .. I.SU 0.86 44
109 0.19 2.8C 2.SU 0.95 31
U-Material was analyzed for but not detected. The number is the minimum quantitation limit.
C-:(:onfirmed by GC/MS.
shaded values -Exceed levels of concern for total PCB residues (0.4 mg/kg fresh weight) in
whole body fish (Eisler 1986). ·
· ..
- - - - - - - -l!!l!!!I l!!!l!!I 11111!1 ----liiii ---
Table 4
Station l
IOI
102
103
104
105
106
107
10s'
109
110
. Comparison of habitat quality for sampling stations on Bat Fork Creek and an unnamed tributary in the vicinity of General
Electric/Shepherd Farm Superfund Site, East Flat Rock, North Carolina. November 1994.
SAMPLING STATIONS Habitat Assessment
Habitat %. Compatibility
Station Description Score Condition Compatibility Assessment
to Background
Background · for Unnamed 99 Good 100 -
. Tributary
Unnamed Tributary 114 Excellent 115 Comparable
Bat Fork Creek 119 Excellent --
(Spring Haven Trailer Park)
Bat Fork Creek 115 Excellent --
Shepherd Farm
Bat Fork Creek 125 Excellent 100 -
Background for GE Site
Bat Fork Creek 94 · Good 75 Supporting
Inside GE Site
Bat Fork Creek 111 Excellent 88 Supporting
Downstream of GE Discharge
Bat Fork Creek 120 Excellent 96 Comparable
Downstream of Sta. I 07
Bat Fork Creek 117 Excellent 94 Comparable
Downstream of GE Site \
Ditch on Seldon Clark Subsite 31 Poor --'
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Record of Decision
GE/Shepherd Farm NPL Site
September 1995
The chemicals of potential concern in soil are chromium VI, copper, lead, cadmium,
molybdenum, aluminum, vanadium, manganese, benzo(a)anthracene, chrysene; benzo(b and/or
k)fluoranthene, benzo-a-pyrene, indeno(l ,2,3-cd)pyrene, dibenzo(a,h)anthracene, dieldrin,
toxaphene, PCB-1254, PCB-1242, PCB-1248, and PCB-1260.
Once these chemicals of potential concern were identified, exposure concentrations in each media
were estimated. Exposure point concentrations were calculated for groundwater and surface
soils using the lesser of the 95 percent upper confidence limit concentration or the maximum
detected value as the reasonable maximum exposure (RMB) point concentration. Exposure point
concentrations for groundwater are shown in Table 5. Exposure point concentrations fo~ each
subsite are presented in Table 6 for soils.
B. Exposure Assessment
The exposure assessment evaluates and identifies complete pathways of exposure to human
population on or near the Site.
Current exposure pathways include exposure through incidental ingestion of soil; inhalation of
fugitive dusts from soils; dermal contact with soils; and ingestion of water from private wells.
Land use assumptions include residential, commercial/ industrial and child visitor scenario.
Future use scenarios consider construction of a water supply well within the groundwater
contaminant plume at GE and Shepherd Farm and ingestion of soil, inhalation of dusts and
dermal contact with soils at Shepherd Farms, as a worse0case scenario. Possible exposure
pathways for groundwater include exposure to contaminants of concern from the groundwater
plume in drinking water and through inhalation of volatiles evolved from water through
household water use. Table 7 shows the site conceptual model used to determine the risk at this
Site. Further detail and mathematical calculations can be reviewed in the Baseline Risk
Assessment.
C. Toxicity Assessment
Under current BP A guidelines, the likelihood of adverse effects occurring in humans from
carcinogens and noncarcinogens are considered separately. These are discussed below. Tables
8 and 9 summarize the carcinogenic and noncarcinogenic toxicity criteria for the chemicals of
potential concern.
Cancer slope factors have been developed by BP A for estimating excess lifetime cancer risks
associated with exposure to potentially carcinogenic chemicals. Slope factors, which are
expressed in units of kg-day/mg, are multiplied by the estimated in!.!15e of a potential carcinogen,
in mg/kg-day, to provide an upper-bound estimate of the excess lifetime cancer risk associated
47
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TABLE 5
Reasonable Maximum Exposure Concentratlons for __.
Chemical of
PoCentlal Concern
BARIUM
BERYLLIUM
MOLYBDENUM
NICKEL
LEAD
STRONTIUM
ALUMINUM
MANGANESE
VINYL CHLORIDE
METHYLENE CHLORIDE
1,1-0ICHLOROETHENE
CIS-1,2-0ICHLOROETHENE
TRANS-1,2-0ICHLOROETHEN
CHLOROFORM
1,2-DICHLOROETHANE
BROMODICHLOROMETHANE
1,2-0ICHLOROPROPANE
il'RICHLOROETHENE
BENZENE
iTETRACHLOROETHENE
1,4-DICHLOROBENZENE
1,2,4-TRIMETHYLBENZENE
· NITROBENZENE
? 4-DINITROPHENOL
.Chemical of
Potenlbl Concern
BARIUM
BERYLLIUM
Chemicals of Potenlbl Concern In Groundwater General Electrlc Site
East Flat Rock, North Carolina
Meanol Standard H (StaUsllc Sample Transformed DevlaUon from Size Data of Data Table)
4.0 1.4 3.on Zl -0.2 0.8 2.202 Zl 0.4 0.7 2.102 Zl 1.3 1.0 2.423 Zl 1.5 0.3 1.793 Zl 4.5 1.7 3.437 Zl 5.6 1.8 3.437 Zl 4.2 2.2 3.812 Zl 1.7 u 3.on Zl 1.8 1.4 3.on. Zl 1.7 1.4 3.077 Zl 2.2 1.9 3.812 Zl 1.6 1.4 3.on 27 1.9 1.3 2.737 27 1.9 1.4 3.on Zl 1.7 1.5 3.on Zl 1.7 1.4 3.on 27 1.9 1.6 3.on Zl 1.7 1.4 3.on Zl 3.4 2.4 4.588 Zl 1.7 1.4 3.on Zl 1.7 1.4 3.on Zl 1.7 0.4 1.856 Zl 2.3 0.3 1.793 Zl
TABLE 5 Reasonable Maximum Exposure ConcentraUons for Chemicals or Potential Concern In Groundwater
Shepherd Farm Site East Flat Rock, North Carolina
Mean of Standard H (Statistic Sample Transformed Deviation from Size Data of Data Table)
4.6 1.4 7.120 4 -0.4 0.6 3,287 4
UCL (1)
(ugn)
379
2
3
11
5
1216
4462
3587
35.0
34.8
36.2
204.9
29.1
33.0
46.5
39.0
37.4
61.5
37.5
4246
36.1
37.6
6.9
11.1
UCL (1)
(ugn)
o/737
2.4 MANGANESE 5.6 1.7 8.250 4 3293793 \llNYL CHLORIDE 0.7 0.4 2.651 4 ~ETRACHLOROETHENE 2.2 1.5 7.120 4
UCL: Upper Confidence LJmij Maximum: The highest detected concentration. RME: Reasonable Maximum Exposure (UCL o, maximum when UCL is greater than maximum) NA: Not Applicabie ·
4
12571
Maximum
(ugn)
4000
15
25
190
15
8000
15000
5000
2.8
5.1
0.8
380.0
33.0
9.4
130.0
0.7
0.5
130.0
2.7
1600
0.8
0.5
36.0
10.0
Maximum
(ugn)
760
1.6
1500
1.1
34
(1 ). Some UCL calculated values are unreasonably high due lo the small sample size and/o, wide range in results.
RME
. (ugn)
379
2
3
11 ._, .. 5
1216
4462
3587
2.8
5.1
0.8
204.9
29.1
9.4
46.5
0.7
0.5
61.5
2.7
1600
0.8
0.5
6,9
10.0
RME
(ugn)
760
1.6
1500
1.1
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Chemlcalof
Potonllal Cancom
c.HROMIUMVI
COPPER
LEAD
IIANAOIUM
ALUMINUM
MANGANESE
BENZO(A)ANTMRACENE
::HRYSENE
BENZO(B AND/OR l<)FLUORANTHENE
BENZO-A-PYRENE . INDENO (1,2,3-<:D) PYRENE
DIBENZO(A,H)ANTHRACENE
DIELDRIN
TOXAPHENE
PCB-1242
PCB-1254
PCB-1248
PCB-1260
Chemic.al of
Potential Cancem
=DMIUM
CHROMIUM VI
COPPER
MOLYBDENUM
LEAD
MANGANESE
PCB-1254
PCB-1248
PCB-1260
UCL: Upper Confidence UmH
TABLE 6
Reasonable Maxlmuffl Expo&ur"e ConcentratJon1 for Chemicals of Potential Concern In Soll
General Electric Site
Eaat Flat Rocle, North Carolina
Meanor Standard . H (Statlallc _Sample Tranafarmed Deviation from Size Data of Data Table)
3.4 0.8 2.443 17 3.5 1.1 2.744 17 3.4 0.5 2.068 17 3.8 0.5 2.068 17 10.5 0.5 2.068 17 5.3 0.8 2.443 17 5.5 0.9 2.589 17 5.5 0.9 2.589 17 5.6 0.9 2.589 17 5.5 0.9 2.589 17 5.5 0.9 2.589 17 5.4 0.9 2.589 17
2.5 1.4 3.612 17 6.8 2.7 5.557 17 3.5 1.7 4.061 17 3.9 2.0 4.564 17 3.7 1.6 3.612 17 4.2 2.1 4.564 17
TABLE 6
Reasonable Maximum Exposure Concentrations for Chemicals of Potential Concern In Soll Shepherd Farm SIie East Flat Rock. North Carolina
Meanor Standard H (Statlalic Sample Transformed Deviation from Size Data of Cata Table)
0.7 0.9 2.902 10 3.7 0.3 1.977 10 5.6 1.9 5.396 10 1.9 1.0 3.103 10 5.0 1.7 4.795 10 5.6 0.3 1.977 10 4.7 2.7 6.621 10 6.9 2.6 6.621 10
5.9 2.6 6.621 10
Maximum: The hlgheat detected concentration. RME: Reasonable Maximum Exposure (UCL or maximum 'Nhen UCL Is greater than rt'\a)lffium)
UCt. (1)
(mg/kg)
63
117
44
66
52409
468
0.7
0.7
0.7
· 0.6
0.6
0.6
0.1
1678
0.9
3.2
0.6
5.9
UCL (1)
(mg/kg)
7
52
57908
31
9431
378
1441 ma
.2887
NA: Not Appricable . (1). Some UCL calculated values are urlreaaonabty high due to the large range of detections and/or amatl sample size.
Maximum RME . (mg/kg) (mg/kg)
120 63 1100 117
130 44 92 66 120000 52409 aso,, 468 0.4 0.4 0.4 0.4
0.5 0.5 0.3 0.3 0.2 0.2
0.1 0.1
0.1 0.1
2.6 2.6
22.0 0.9 9.3 3.2
9.7 0.6 26.0 5.9
Maximum RME (mg/kg) (mg/kg)
10 7
62 52
20000 20000
50 31
9600 . 9431
470 378
7.3 7.3
11.0 11.0
4.0 4.0
TABLE 7
SITE CONCEPTUAL MODEL
SOURCE PRIMARY RELEASE/ AFFECTED MEDIUM EXPOSURE EXPOSURE ROUTE RECEPTOR
TRANSPORT POINT
MECHANISM
SHEPHERD FARM NA SURFACE SOIL ON-SITE INGESTION RESIDENT LANDFILL DERMAL CONTACT VISITOR
LEACHING GROUNDWATER ON-SITE INGESTION RESIDENT*
INHALATION OF voes
SURF ACE EROSION SURFACE WATER IN OFF-SITE INGESTION RESIDENT
CREEK DERMAL CONTACT VISITOR
SEDIMENTIN OFF-SITE INGESTION RESIDENT
CREEK DERMAL CONTACT VISITOR
DUST GENERATION AIR OFF-SITE INHALATION RESIDENT
VISITOR
GE NA SURFACE SOIL ON-SITE INGESTION WORKER
LANDFILLS
DERMAL CONTACT VISITOR
LEACHING GROUNDWATER ON-AND OFF-INGESTION WORKER
LANDSPREADING SITE INHALATION OF voes RESIDENT
PLOT~ SURFACE EROSION SURFACE WATER IN OFF-SITE INGESTION VISITOR
TREATMENT CREEK DERMAL CONTACT
PONDS SEDIMENTiN OFF-S,ITE INGESTION VISI\R CREEK DERMAL CONTACT
DUST GENERATION AIR ON-SITE INHALATION woRdR
VISITOR
"' Iiicludes children who are not permitted to reside in the mobile home community but may visit. ·
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TABLE 8
· Cancer Sk>pe factors. Tumor Sites and EPA Cancer Clascificatlons for _.-. -· ---Chemicals of Potenlial Concern
General Electric Site
, East Flat Rock, North C..rolina
Chemical of CMCer Slope Factor/ Unit Rlsk
Potential Concern .. CSFo Unit RJsk CSFI
BARIUM
SERYLUUM
CADMIUM
CHROMIUM VI
COPPER
MOLYBDENUM
NICKEL
LEAD
STRONTIUM
lvANADIUM
!ALUMINUM
MANGANESE MNYL CHLORIDE
METHYLENE CHLORIDE
CARBON DISULFIDE
1, 1-DICHLOROETHENE ~i ,2-DICHLOROETHENE
NS-1,2-DICHLOROETHENE
CHLOROFORM
1,2-DICHLOROETHANE
BROMODICHLOROMETHANE
~-DICHLOROPROPANE
ICHLOROETHENE
BENZENE
TETRACHLOROETHENE
1,4-DICHLOROBENZENE
1,2.4-TRIMETHYLBENZENE
NITROSENZENE
2.4-DINITROPHENOL
BENZO(A)ANTHRACENE
CHRYSENE
BENZO(B AND/OR K)FLUOR·
ANTHENE'
BENZO(A)PYRENE
INDENO(l ,2.3-CD)PYRENE
DIBENZO(A,H)ANTHRACENE
DIELDRIN
iTOXAPHENE
PCB-1242
PCB-1254
PCB-1248
PCB-1260
Sources:
1-IRIS
h-HEAST
e-ECAO
nnh'
NA NA
l4.3E+OO I 2.4E-03
NA 1.BE-03
NA 1.2E-02
NA NA
NA NA
NA NA
NA NA
NA NA
NA NA
NA NA
NA NA
1.9E+OO h 8.4E--05
7.SE-03 I 4.7E-07
NA NA
6E-01 I 5.0E--05
NA NA
NA NA
6.1 E-03 I 2.3E--05
9.IE--02 I 2.6E--05
6.2E-02 I NA
6.BE--02 h NA
1.IE--02 w 1.7E-06
2.9E-02 I 8.3E-06
5.2E-02 e 5.9E-07
2.4E-02 h NA
NA NA
NA NA
NA NA
7.3E-01 e NA
7.3E-03 e NA
7.3E-01 e NA
17.3E+OO I NA
7.3E-01 e NA
17.3E+OO • NA
1.6E+01 I 4.6E-03
1.1E+OO I 3.2E-04
17.7E+OO I NA
7.7E+OO I NA
7.7E+OO I NA
7.7E+OO I NA
w • Withdrawn from IRIS or HEAST
•·Relative potency of benzo(b)fluoranthene used
CSFo • Cancer Slope Factor (oraQ, (mg/kg/day)-1
Unit Risk (Inhalation)-(ug/cu m)-1
CSFI • Cancer Slope Factor Qnhalatlon), (mg/kg/day)-1
CSFd • Cancer Slope Factor (dermal), (mg/kg/day)-1
NA
I 8.4E+OO I
I 6.3E+OO I
I 4.2E+01 I
NA
NA
NA
NA
NA
NA
NA
NA
h 2.9E:01 h
I 1.65E-03 I
NA
I 1.75E-01 I
NA
NA
I 8.0SE--02 I
I 9.IE-02 I . NA
NA
e 6.0E-03 • I 2.9E-02 I
e 2.0SE-03 · e
NA
NA
NA
NA
3.IE-01 e
3.1 E-03 e
3.IE-01 e
3.IE+OO e
3.IE-01 e
3.IE+OO e
I 1.6E+01 I
I 1.IE+OO I
NA
NA
NA
NA
ABSeff
NA
20% . NA
NA
NA
NA
NA
NA
NA
NA.
NA
NA
80%
80%
NA
80%
NA
NA
80%
80%
NA
NA
80%
80%
80%
80%
NA
NA
NA
50%
50%
50%
50%
50%
50%
50%
50%
50%
50%
50%
50%
ABSeff. Abso<ptlon efficiency: 20% lnorganlcs, 50% &ernlvlolatiles, 80% volatiles NA • Not Applicable (no data)
Tumor Situ
CSFd Oral lnhalaUon
NA NA NA
2.2E+01 All sites lung
NA NA lung, 1rachea
NA NA lung
NA NA NA
NA NA NA
NA . NA NA
NA Kidney NA
NA NA NA
NA NA NA
NA NA NA
NA NA NA 2.4E+OO Lung' liver Uver
9.4E-03 · Liver Uver, mammaries
NA NA NA
7.SE-01 Adrenals Kldney
NA NA NA
NA NA NA 7.6E-03 Kidney Uver
1.IE-01 Severalsiles Several sites
NA Kldney NA
NA Uver NA
1.4E-02· Liver Uver
3.6E-02 Leukemia Leukemia
6.SE-02 Uver Uver
NA Liver NA
NA NA NA
NA NA NA
NA NA NA
1.5E+OO Forestoinach ResplratO/)' tract
1.SE-02 F0<estoinach ResplratO/)' tract
1.SE+OO Forestoinach ResplratOI)' tract
1.SE+OI Forestoinach Respiratory tract
1.SE+OO Forestoinach Resplratocy tract
1.SE+OI Forestoinach Resplratocy tract :i.2e+01 Liver Uver 2.2E+OO Liver Liver
1.SE+OI Liver NA
1.SE+OI Liver NA
1.SE+OI Liver NA
1.SE+OI Liver NA
EPA Class:
A -Human carcinogen
B -Probable human carcinogen
C -Possible human carcinogen
D -Not classma~ as a human carcinogen
EPA
Class
D
82
Bl
A
D
D
D
82
D
D
D
D
A
82
D
C
D
D
82
B2
82
82
82
A
82
B2
D
D
D
82
B2
B2
B2
82
82
B2
82.
82
B2
B2
B2
I
I
I
I
I
0
D
I
I
I
I
I
I
I
I
I
Chemlcalol
Potential Concern
BARIUM
BERYLLIUM
CADMIUM (water)
ICADMIUM (food)
!CHROMIUM VI
COPPER
MOLYBDENUM
NICKEL
LEAD
STRONTIUM
VANADIUM
ALUMINUM
MANGANESE (water)
MANGANESE (food)
VINYL CHLORIDE
METHYLENE CHLORIDE
CARBON DISULFIDE
1,1-DICHLOROETHENE
CIS-1,2-0ICHLOROETHENE
TRANS-1,2-DICHLOROETHEN
CHLOROFORM
1,2-0ICHLOROETHANE
BROMODICHLOROMETHANE
1,2-0ICHLOROPROPANE
TRICHLOROElliENE
BENZENE
, , -• , ;,: CHLOROETHENE
1,4-DICHLOROBENZENE
1,2,4-TRIMETHYLBENZENE
NITROBENZENE
2,4-0INITROPHENOL
BENZO(A)ANTHRACENE
CHRYSENE .
BENZO(B AND/OR K)FLUOR-
ANlliENE
BENZ0,A..PYRENE
INDENO(1,2,3-CD)PYRENE
DIBENZO(A,H)ANTHRACENE
DIELDRIN
[TOXAPHENE
PCB-1242
PCB-1254
PCB-1248
PCB-1260
Soun:es:
1-IRIS
h• HEAST
e-ECAO
TABLE 9
· Reference Doses and Target Sites for
Chemicals of PotentJal Concern
General Electrtc Site
East Flat Rock, North Carolina
Reference Dose/ Concentration T1rvet Sites/ Effects
RIDo RfC. RICI ABSell
7E-02 I SE-04 h 1.43E-04 h 20%
SE-03 I NA NA 20%
SE-04 I NA NA 20%
1E-03 I NA NA 20%
5E-03 I NA NA 20%
3.71E-02 h NA NA 20%
5E-03 I NA NA 20%
2E-02 I NA NA 20%
NA NA NA NA. 6E-01 I NA NA 20%
7E-03 h NA NA 20%
1 E-+-00 e NA NA 20%
5E-03 I NA NA 20%
1.4E-01 I SE-05 I 1.43E-05 I 20%
NA NA NA 80%
6E-02 I 3E-+-OO h 8.57E-01 h 80%
1E-01 I NA 2.86E-03 h 80%
9E-03 I NA NA 80%
1E-02 h NA NA 80%
2E-02 I NA NA 80%
1E-02 i NA NA 80%
NA NA 2.86E-03 e NA
2E-02 I NA NA 80%
NA 4E-03 I 1.14E-03 I NA
6E-03 e NA NA 80%
NA NA 1.71E-03 e NA
1E-02 I NA NA 80%
NA 8E-01 I 2.29E-01 i NA
SE-04 e NA NA 80%
SE-04 i 2E-03 h 5.71E-04 h 80%
2E-03 I NA . NA 80%
NA NA NA NA
NA NA NA NA
NA NA NA NA
NA NA NA NA
NA NA NA NA
NA NA NA NA
SE-05 I NA NA 50%
NA NA NA NA
NA NA NA NA
2E-05 I NA NA 50%
NA NA NA NA
NA NA NA NA
R!Do. Reference Dose (oral), (mg/kg/day)
RIC -Reference Concentration (air), (mg/cum)
RfDi • Reference Dose ~nhalation), (mg/kg/day)
RIDd Oral
1E-02 Iner. blood pressure
1E-03 NOAEL
1E-04 Prcteinuria
2E-04 NOAEL
1E-03 NOAEL.
7E-03 GI irritation
1E-03 Iner. uric acid levels
4E-03 Deer. bodyio,gan wta.
NA CNS effects, blood
1E-01 Rachitic bone
1E-03 NOAEL
2E-01 Unspecified
1E-03 CNS effects
3E-02 NOAEL
NA NA
SE-02 Liver
SE-02 Fetal tox/ma~ormation
7E-03 Liver
SE-03 Deer. hematocrit
2E-02 Iner. serum phosphatase
SE-03 Fatty cyst in liver
NA NA
2E-02 Renal cytomegaly
NA NA
SE-03 Liver
NA NA
SE-03 Liver
NA NA
4E-04 Not specified
4E-04 Blood, adrenal, kidney
2E-03 Cataract formation
NA NA
NA NA
NA NA
NA NA
NA NA
NA NA
3E-05 Liver
NA NA
NA NA
IE-05 Eyes, nails, immune syst.
NA NA
NA NA
ABSeff • Abso<ption effociency: 20% ino<ganics, 50% semMOlatiles, 80% volatiles
RIDd • Reference Dose (dermal), (mg/kg/day) -·
NA • Not Applicable (no data)
lnhalatlon
Felotaxicity
NA
NA
NA ..
NA
NA
NA
NA
CNS effects, blooc
NA
NA
NA
NA
NOAEL
NA
Liver
NA
NA
NA
NA
NA
Not specified
NA
Nasal mucosa
NA
Not specified
NA
Liver
NA
Blood
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
I
g
I
I
I
g
I
I
u
H
I
I
I
I
I
I
Record of Decision September !995 GE/Shepherd Fann NPL Site
with exposure at that intake level. The term "upperbound" reflects the conservative estimate of the risks calculated from the slope factor. Use of this approach makes underestimation of the actual cancer risk highly unlikely. Cancer potency factors are derived from the results of human
epidemiological studies or chronic animal bioassays to which animal-to-human extrapolation and uncertainty factors have been applied.
Reference doses (RfDs) have been developed by EPA for indicating the potential for adverse
health effects from exposure to chemicals exhibiting noncarcinogenic effects. RfDs, which are
expressed in units of mg/kg-day, are estimates of lifetime daily exposure levels for h\lJIIans,
including sensitive individuals. Estimated intakes of chemicals from environmental media can be compared to the RID. RfDs are derived from human epidemiological studies or animal
studies to which uncertainty factors have been applied. These uncertainty factors help ensure
that the RfDs will not underestimate the potential for adverse noncarcinogenic effects to occur.
D. Risk Characterization
The risk characterization step of the Site risk assessment process integrates the toxicity and exposure assessments· into quantitative and qualitative expressions of risk. The output of this process is a characterization of the Site-related potential noncarcinogenic and carcinogenic health effects.
Potential concern for noncarcinogenic effects of a single contaminant in a single medium is expressed as the hazard quotient (HQ), or the ratio of the estimated intake derived from the contaminant concentration in a given medium to the contaminant's reference dose. By adding the HQs for all contaminants within a medium or across all media to which a given population
may be reasonably exposed, the Hazard Index (HI) can be generated. Calculation of a HI in
excess of unity indicates the potential for adverse health effects. Indices greater than one will·
be generated anytime intake for any of the chemicals of concern exceeds its Reference Dose
(RID). However, given a sufficient number of chemicals under consideration, it is also possible to generate a HI greater than one even ·if none of the individual chemical intakes exceeds their
respective RfDs.
Carcinogenic risk is expressed as a probability of developing cancer as a result of lifetime
exposure .. Excess lifetime cancer risks are determined by multiplying the intake level with the cancer potency factor. EPA's acceptable target range for carcinogenic risk is one-in-ten-
thousand (lE-4) to one-in-one-million (lE-6).
Current Use
Cancer and noncancer risks for the current use scenario for tb.l; Shepherd Farm Site are
summarized in Table 10. Noncancer health effects are considered possible for an adult and·
53
l!!!!!!I !!11!1 91!1 a!! 11111 11:=1 r:= all 111111 liiiiiiil -liilii lilil liiii !iii&
TABLE 10
Summary of Cancer and Noncancer Risks by Exposure Route Current Use Scenario
Location Exposure
Route
Site Surface Inadvertent Ingestion
Soil Dermal Contact
Inhalation of Dust
Stream Inadvertent Ingestion
Water Dermal Contact
Stream Inadvertent. Ingestion
Sediment Dermal Contact
TOTAL CURRENT RISK
Hi Hazard Index (noncancer nsk) NA. Not Applicable
'.
Shepherd Farm Site
East Flat Rock, North Carolina
Child Resident Adult Resident
Cancer HI Cancer HI
2E-04 12 BE-05 1 9E-05 3 BE-05 0.7 3E-07 BE-12 3E-07 2E-12
1E-09 0.00003 1E-09 0.00001 9E-09 0.0002 BE-09 0.00004
NA 0.001 NA 0.0001 NA 0.0001 NA 0.00003
3E-04 15 2E-04 2
Lifetime Resident
(6-vr + 24-yr)
Cancer HI
3E-04 3
2E-04 1
6E-07 3E-12
3E-09 0.00001
2E-0S 0.0001
NA 0.0002
NA 0.00005
4E-04 5
.
Site Visitor
Cancer HI
4E-06 0.1
4E-06 0.1
1E-08 2E-13
' BE-10 0.00001
5E-09 0.0001
NA 0.0002
NA 0.00005
7E-06 0.2
\
I
I
I
I
R
I
I
I
I
I
I
I
I
I
I
I
I
Record of Decision September 1995
GE/Shepherd Farm NPL Site
child resident, as well as a lifetime resident. Noncancer health effects are not expected for the
site visitor. Estimates of cancer risk for a child resident (3E-04), adult resident (2E-04) and the
lifetime resident (4E-04) were above the acceptable range.
Future Use
Cancer and noncancer risks associated with the future use scenario are summarized in Table 11
for the GE Site and Table 12 for the Shepherd Farm Site. As measured by hazard indices,
noncancer health effects are considered possible due to ingestion of groundwater obtaine<l from
within the contaminant plume. Unacceptable. cancer risks are also considered possible due to
the contantination.
Contaminant Risk
The quantified carcinogenic risks and noncarcinogenic hazard indices for each chemical of
concern are given in Tables 13, 14, and 15 for soil and groundwater.
E. Ecological Risk Assessment
Potential pathways by receptor groups is shown in Table 16. The exposure media are surface
soils, sediments, and surface waters. Bat Fork Creek along the GE property has been impacted
by releases from the site; however, the stream appears to be recovering as it flows past the Site.
PCBs were detected in fish at levels that are considered harmful. Additional downstreain fish
tissue sampling is recommended to fully characterize the extent of PCB contamination in the fish
population and to assess potential impacts on secondary consumers (e.g., kingfishers, heron, or
other fish-eating species) that are known to occur downstream of the site. EPA will incorporate
this sampling as part of the remedy.
F. Conclusions
Actual or threatened releases of hazardous substances from this Site if not addressed by
implementing the response action selected in this ROD, may present an imminent and substantial
endangerment to public health, welfare, or the environment.
VII. APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS (ARARS)
In accordance with Section 121 of CERCLA, remedial actions must be protective of human
health and the environment and must comply with all federal, state, and local applicable or
relevant and appropriate requirements. The remediation goals must nieet regulatory
requirements and protect human health and the environment. This section will present the
55
- - - ---l!l!!I I!!!!!! a!! . -111!!1 ;;;; ----liiiial liiiil . ·iiiii)
Location Exposure
Route
Site Surface Inadvertent Ingestion
Soil Dermal Contact
Inhalation of Dust
Stream Inadvertent Ingestion
Water Dermal Contact
Stream Inadvertent Ingestion
Sediment Dermal Contact
Groundwater Ingestion
Inhalation or VOCs
TOTM. FUTURE RISK
HI Hazard Index (noncancer risk)
NA Not Applicable
TABLE 11
Summary of Cancer and Noncancer Risks by Exposure Route
Future Use Scenario
General Electric Site
East Flat Rock, North Carolina
Child Resident Adult Resident Lifetime Resident
16-vr + 24-vrl
Cancer HI Cancer HI Cancer HI
NA NA NA NA NA NA
NA NA NA NA NA NA
NA NA NA NA NA NA
NA NA NA NA NA NA
NA NA NA NA NA NA
NA NA NA NA NA NA
NA NA NA NA NA NA
6E-04 60 9E-04 26 2E-03 34
NA NA 9E-05 0.8 9E-05 0.8
6E-04 60 1E-03 27 2E-03 35
On-site Worker Site Visitor
Cancer HI Cancer HI
2E-05 0.1 2E-06 0.04
1E-05 0.1 2E-06 0.03
3E-07 2E-12 2E-08 3E-13
NA NA 2E-09 0.01
NA NA 1E-08 0.001
NA NA 6E-08 0.001
NA NA 6E-08 0.001
' '
4E-04 9 NA NA
3E-05 0.3 NA NA
4E-04 10 4E-06 0.1
\
\
-------------------
TABLE 12
Summary of Cancer and Noncancer Risks by Exposure Route
Future Use Scenario
Shepherd Fann Site
East Flat Rock, North Carolina
Location Exposure Child Resident Adult Resident Lifetime Resident
{6-vr + 24-vrl
Route
Cancer HI Cancer HI Cancer HI
Site Surface inadvertent Ingestion 2E-04 12 SE-05 1 3E-04 3
Soil Dermal Contact 9E-05 3 SE-05 0.7 2E-04 1
Inhalation of Dust 3E-07 SE-12 3E-07 2E-12 6E-07 3E-12
Stream Inadvertent Ingestion 1E-09 0.00003 1E-09 0.00001 3E-09 0.00001
Water Dermal Contact 9E-09 0.0002 SE-09 0.00004 2E-08 0.0001
Stream Inadvertent Ingestion NA 0.001 NA 0.0001 NA 0.0002
Sediment Dermal Contact NA 0.0001 NA 0.00003 NA .0.00005
I .
Groundwater Ingestion · 6E-05 20. 1E-04 9 2E-04 11
Inhalation of voes NA NA 4E-06 NA 4E-06 NA
TOTAL FUTURE RISK 3E-04 35 3E-04 11 SE-04 16
HI Hazard Index (noncancer risk)
Site Visitor
Cancer HI
4E-06 0.1
4E-06 0.1
1E-08 2E-13
SE-10 0.00001
5E-09 0.0001
NA 0.0002
NA 0.00005
NA NA
NA NA
\
7E-06 ·0.2
\
'
------------------~
CHEMICALS OF
CONCERN
SHEPHERD FARM
CHILD RESIDENT
SCENARIO
CADMIUM
CHROMIUM VI
COPPER
MOLYBDENUM
PCB-1254
PCB-1248
PCB-1260
SHEPHERD FARM
ADULT RESIDENT
SCENARIO
COPPER
PCB-1254 I
PCB-1248
PCB-1260
GE ON-SITE
WORKER SCENARIO
FCB-1242
PCB-1254
PCB-1260
TABLE 13
CHEMICALS OF CONCERN -SOIL
INCIDENT AL INGESTION DERMAL CONTACT
CANCER RISK HAZARD CANCER HAZARD
QUOTIENT RISK QUOTIENT
NA 0.1 NA 0.01
NA 0. 1 NA 0.02
NA 7 NA 0.9
NA 0.1 NA 0.01
6E--05 5 3E--05 2
9E--05 NA 5E--05 NA
3E--05 NA '2.E--05 NA
NA 0.7 NA 0.2
JE--05 0.5 3E--05 0.5
4E--05 NA 4E--05 NA
IE--05 NA lE--05 NA
IE--06 NA 9E--07 NA
4E--06 0.1 3E--06 0.1
SE--06 NA 6E--06 NA
INHALATION OF DUST SELECTION
BASIS
CANCER HAZARD
RISK QUOTIENT
6E--09 NA 1
3E--07 NA 1
NA NA· 1
NA NA 1
NA NA 1
NA NA 1
NA NA 1
'
NA NA 1
NA NA 1
NA NA 1
NA NA 1
\ ' i ' NA NA 1
NA • NA 1
NA NA 1
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
Chemical• of Concern
n . • I t. • BARIUM
BERYLLIUM
NICKEL
LEAD
MANGANESE
VINYL CHLORIDE
METHYLENE CHLORIDE
1, 1-0ICHLOROETHENE
CIS-1,2-0ICHLOROETHENE
CHLOROFORM
1,2-0ICHLOROETHANE
tmlCHLOROETHENE
BENZENE
,~,,___,HLOROETHENE
•1TROBENZENE
~h I I d R • IUM
BERYLLIUM
NICKEL
LEAD
STRONTIUM
ALUMINUM .
MANGANESE
VINYL CHLORIDE
METHYLENE CHLORIDE
1,1-DICHLOROETHENE
CIS-1,2-DICHLOROETHENE
TRANS-1,2-0ICHLOROETHENE
CHLOROFORM
1,2-0ICHLOROETHANE
TRICHLOROETHENE
BENZENE
rETRACHLOROETHENE
1,2,4-TRIMETHYLBENZENE
NITROBENZENE
Z,4-DINITROPHENOL
d u I I R • BARIUM
BERYLLIUM
NICKEL
LEAD
isTRONTIUM
!ALUMINUM
MANGANESE
MNYL CHLORIDE
"'ETHYLENE CHLORIDE
1, 1-DICHLOROETHENE
iclS-1,2-DICHLOROETHENE
icHLOROFORM
1,2-0ICHLOROETHANE
TRICHLOROETHENE
BENZENE
TETRACHLOROETHENE
NITROBENZENE
4-DINITROPHENOL
TABLE 14
Chemicals of Concern
Groundwater
o.n.t'al Electric Site
Eut Flat Roel<, North Carolina
cation
Cance< Hazard Cance,
Risk Quotient Risk
w 0 r k • r s
NA 0.1 NA
2E-05 0.003 NA
NA 0.01 NA
NA NA NA
NA 7 NA
2E-05 NA 3E-06
1E-07 0.001 3E-08
2E-06 0.001 SE-07
NA 0.2 NA
2E-07 0.01 3E-06
1E-05 NA 1E-05
2E-06 0.1 1E-06
3E-07 NA-3E-07
3E-04 2 1E-05
NA 0.1 NA • I d • " I s
NA 0.3 NA
◄E-05 0.02 NA
NA ·0.03 NA
NA . NA NA
NA 0.1 NA
NA 0.3 NA
NA -46 NA
3E-05 NA NA
2E-07 0.01 NA
3E-06 0.01-NA
NA 1 NA
NA 0.1 NA
3E-07 0.1 NA
2E-05 NA NA
◄E-06 0.7 NA
4E-07 NA NA
SE-04 10 NA
NA 0.1 NA
NA 0.9 NA
NA 0.3 NA
• I d • " I s
NA 0.1 NA
6E-05 0.01 NA
NA 0.01 NA
NA NA NA
NA 0.1 NA
NA 0.1 NA
NA 20 NA
SE-05 NA 8E-06
4E-07 0.002 8E-08
4E-06 0.002 1E-06
NA 0.6 NA
SE-07 0.03 7E-06
◄E-05 NA ◄E-05
SE-06 0.3 3E-06
7E-07 NA 7E-07
SE-04 4 3E-05
NA 0.4 NA
NA 0.1 NA
1. Exceeds excess cancer risk of 1 x E-6 and/or HQ of0.1
2. Exceeds ARAR
NA Ml applicable
ofVOC& 1 Se1ect1on
Hazard I Bula
Quotient
C • n • r I 0
NA 1.2·
NA 1,2
NA 2
NA 2
NA 1,2
NA 1,2
0.0001 2
NA 1
NA 1,2 NA 1,2
0.2 1,2
NA . 1,2
0.02 2
NA 1,2
0.1 1
C • n • r I 0
NA 1,2
NA 1,2
NA 2
NA 2
NA 1
NA 1
NA 1,2
NA 1,2
NA 2
NA 1
NA 1,2
NA 1
NA 1,2
NA 1,2
NA 1,2
NA 2
NA 1,2
NA 1
NA 1
NA 1
C • " a r I 0
NA 1,2
NA 1,2
NA 2
NA 2
NA 1
NA 1
NA 1,2
NA 1,2
0.0002 2
NA 1
NA 1,2
NA 1,2
0.4 1,2
NA 1,2
0.04 2
NA 1,2
0.3 1
NA 1
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Chemlcal_s of Concern
C h I I d R BARIUM
BERYWUM
MANGANESE
VINYL CHLORIDE
TETRACHLOROETHENE
A d u I t R e BARIUM
BERYLLIUM
MANGANESE
!VINYL CHLORIDE
TETRACHLOROETHENE
TABLE 15
Chemicals of Concern
Groundwater
Shepherd Farm Site
East Flat Rock, North Carolina
Ingestion Inhalation of voes Cancer Hazard Cancer Hazard Risk Quotient Risk Quotient e s I d e n -t s C e n NA 0.7 NA NA 4E-05 0.02 NA NA NA 19 NA NA 1E-05 NA NA NA 1E-05 0.2 NA NA s I d e n t s C e n . a r I NA 0.3 NA NA sE~os 0.01 NA NA NA 8 NA NA 2E-05 NA 3E-06 NA 2E-05 0.1 7E-07 NA
1. Exceeds excess cancer risk of 1 x E-6 and/or HQ of 0.1 2. Exceeds ARAR
NA not applicable
Selection
Basis
a r I 0
. 1
1
1
1,2
1,2
0
1
1
1,2
1,2
1 2
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TABLE 16
POTENTIAL PATHWAYS BY RECEPTOR GROUPS GENERAL ELECTRIC/SHEPHERD FARM SITE EAST FLAT ROCK, NORffl CAROLINA
EXPOSURE EXPOSURE POTENTIAL RECEPTORS MEDIA TYPE
Soil Invertebrates, Terrestrial Surface Soil Direct Plants, Amphibians, and Wildlife
.
-. Soil Invertebrates and Wildlife Soil/Grit Direct
Plant-eating Invertebrates, Surface Soil Indirect Reptiles, and Wildlife
Aquatic Biota and Wildlife Surface Water Direct
Wildlife (Birds and Mammals) Surface Water Direct
Wildlife and Fish Surface Water Indirect
Benthic Invertebrates, Bottom-Sediment Direct Feeding Fish, and Wildlife
Benthic Invertebrates, and Sediment Direct Wildlife •
Wildlife and Fish Sediment Indirect
·EXPOSURE
ROUTE
. Absorption or
Direct Contact
Ingestion
Diet
Absorption or
Direct Contact
Ingestion
Diet
Absorption or
Direct Contact
Ingestion
Diet
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Record of Decision September 1995
GE/Shepherd Farm NPL Site
----· · ARARs and present the remediation goals.
The requirement that ARARs be identified and complied with during the development and
implementation of remedial actions is found in Section 12l(d)(2) of CERCLA, 42 U.S.C.
Section 962l(d)(2). This section requires that for any hazardous substance remaining onsite, all .
federal and state environmental and facility citing standards, requirements, criteria, or limitations
shall be met at the completion of the remedial action to the degree that those requirements are
legally applicable or appropriate and relevant under the circumstances presented at the site.
Three classifications of requirements are defined by EPA in the ARAR determination process:
•
•
•
A.
Chemical-specific: These requirements set protective remediation levels for the
chemicals of concern.
Location-specific: These requirements restrict remedial actions based on the
characteristics of the site or its immediate surroundings, and are based on where
the action takes place.
Action-wecific: These requirements set controls or restrictions on the design,
implementation, and performance levels of activities related to the management
of hazardous substances, pollutants, or contaminants.
Chemical-Specific ARARs
Chemical-specific ARARs include those laws and regulations governing the release of materials
possessing certain chemical or physical characteristics, or containing specified chemical
compounds. Chemical-specific requirements set health-or risk-based concentration limits or
ranges in various environmental media for specific hazardous substances, contaminants, and .
pollutants. These ARARs, when applied to site-specific conditions, establish numerical values
that define the acceptable amount or concentration of a chemical that may be found in, or
discharged to, the ambient environment. Examples include drinking water standards and ambient
air quality standards. Chemical-specific ARARs are established once the nature of the
contamination at the site has been defined, which is accomplished during the RI. Chemical-
specific ARARs for this site are listed in Table 17.
B. Location-specific ARARs
Location-specific ARARs are design requirements or activity 4estrictions based on the
geographical or physical positions of the site and its surrounding area. Location-specific
62
FEDERAL
Safe Drinking Water Act
National Primary Drinking Water Standards
National Secondary Drinking Water Standards
Maximum Contaminant Level (MCL) Goals
Clean Water Act
Water Quality Criteria
Resource Conservation and Recovery Act (RCRA), as amended
RCRA Groundwater Protection
Clean Air Act
National Primary and Secondary Ambient Air Quality Standards
National Emissions Standards for Hazardous Air Pollutants (NESHAP,)
Guidance on Remedial Actions for Superfund Sites with PCB
Contamination
Cleanup Level Determination
~
North Carolina Drinking Water Act
North Carolina Drinking Water and Groundwater.Standards
North Carolina Water Quality Standards
North Carolina Surface Water Effluent Limitations
North Carolina Air Pollution Control Regulations
North Carolina Hakrdous Waste Mana.gement Rules
40 USC Section 300
40CFRPart 141
40 CFR 143
40 CFR 141
33 USC Section 1251-1376
40 CFR Part 131
42 use 6905
6912, 6924, 6925
40 CFR. Part 264
40 USC 1857
40 CFR Part 50
40 CFR. Part 61
OSWER Directive
No. 9355.4-01
Chapter 3
130ANCAC 311-327
!SA NCAC 2L
ISA NCAC 2B.0100
&0200
ISA NCAC 2B.0400
ISANCAC 2D
ISANCAC 13A.0009 & .0012
Establishes health-based standards for public water systems (MCLs). .
Establishes welfare-bftsed standards for public water systems (secondary MCLs).
Establishes drinking water quality goals set at levels of no known or anticipated adverse healtli effects.
Sets criteria for water quality based on toxicity to aquatic
organisms and human health.
Provides for groundwater J'rotection standards, general monitoring requirements, an technical requirements.
Sets primary and secondary air standards at levels to protect pubhc health and public welfare.
Provides emissions standard for hazardous air pollutants for which no ambient air quality standard exist.a ..
Directive which describes EPA's recommended approach
for evaluating and remediating Superfund sites w1ili PCB contamination.
Describes various· considerations pertinent to determining
the aperopriate level of PCBs tliat can be left in each
contannnated media to achieve tho protection of human health and tho environment.
Regulates water systems within the atato that supply drinking water that may affect the public health.
Establishes groundwater classification and water quality standards. .
Establishes a series of classifications and water quality standards for surface water. ·
Establishes limits and guidelines for effluent discharged
to waters of the state. .
Regulates ambient air quality and establises air quality
standards for hazardous air pollutants..
· Establishes standards for hazardous .;;asto treatment facilities.
-l!!!!!!!!!I -
The MCI.a for Organic and inorganic contaminants arc applicable to tho groundwater contaminated by tho site since tho aquifer is a drinking water source.
Secondary MCLa for organic and inorganic contaminanta are
guidelines to be considered for groundwater since it is a drinking water source.
MCLOs for organic and inorganic contaminants are applicable to
the groundwater since it is a drinking water source.
May be relevant and appropriate if groundwater, either treated
or untreated, is discharged to a surface water body. Also
relevant and appropriate to any runoff from contaminated soil or soil remediation activities.
RCRA groundwater protection standards are relevant and appropriate for groundwater at the site.
May be relevant and appropriate if onsite treatment units or excavation are a part of remedial action.
May be relevant and appropriate if onsite treatment units or excavation are a part of remedial action.
Guidelines to be considered for PCB--<:ontaminated surface soils at tho aite.
Provides tho state with the authority needed to assume primary
enforcement responsibility under the fedef\1 act.
Guidelines for allowable levels of toxic o}ganic and ino~anlc
compounds in groundwater used for drinking water. Applicable
to groundwater at tho aito. \
May be applicable if treated groundwater is discharged to surface watera.
May be applicable if treated groundwater is discharged to supace water.
May be applicable if, onsite treatment or excavation is part of
Remedial :.\ction. ·--
May be applicable if hazardous waste is excavated and stored or
treated as art of the Remedial Action.
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Record of Decision September 1995
GE/Shepherd Fann NPL Site
requirements set restrictions on the types of remedial activities that can be performed based on
site-specific characteristics or location. Examples include areas in a flood plain, a wetland, or
a historic site. Location-specific criteiia are generally established early in the RI/FS process
since they are not affected by the type of contaminant or the type of remedial action
implemented. Location-specific ARARs for this site are listed in Table 18.
C. Action-specific ARARs
Action-specific ARARs are technology-based, establishing performance, design, or other similar
action-specific controls or regulations for activities related to the management of hazardous
substances or pollutants. Action-specific requirements are triggered by the particular remedial
alternatives that are selected to accomplish the cleanup of hazardous wastes. An example
includes the Resource Conservation and Recovery Act (RCRA) incineration regulations. Action-
specific ARARs for this site are listed in Table 19 and Table 20 for soil and groundwater,
respectively.
Media of Concern
Based on the results of the remedial investigation and the baseline risk assessment, the
GE/Shepherd Farm Site is comprised of two contaminated media; soil and groundwater.
Surface water was not included as a medium of concern based on the fact that if groundwater
feeding the surface water in the area is remediated and if discharge to Bat Fork Creek from the
wastewater treatment ponds is terminated, surface water will be remediated. The approach used
is based on remediation of the source. Surface water quality will be monitored to determine the
effectiveness of this approach.
VIII .. REMEDIAL ACTION OBJECTIVES
Considering the requirements for risk reduction and the risk-based remediation levels derived
in the Baseline Risk Assessment, and the ARARs discussed previously, the remediation goals
specifically developed for the soil in the source areas of the GE/Shepherd Farm Site are
presented in Table 21. The remediation goals for groundwater across the entire site are
presented in Table 22.
The remediation goals, presented in Tables 21 and 22, were selected as the most conservative
of the chemical specific ARARs, the health-based risk goals, and the contract required
quantitation limit (CRQL) that was attainable. The background concentration would have been
selected as the remediation goal if it had exceeded the risk-based goal, as is the normal
procedure. Remediation goals were also selected based on present aiul•future land use at the site,
assuming the GE Subsite would remain commercial/industrial, and Shepherd Farm Subsite to
64
----- ---- -- --- --1!!!11!!!!!1
fABLE 18 -LOCATION-SPECIFIC ARARS, CRITERIA, AND GUIDANCE FOR THE GE/SHEPHERD FARM SITE
~
Resource Conservation and Recovery Act (RCRA),
as amended.
RCRA Location Standards
Fish and Wildlife Conservation Act
Floodplain Management Executive Order
Endangered Species Act
Wetlands Management Executive Order
STATS I
North Carolina Hazardous Waste Management
Rules
North Carolina Solid Waste Management Rules
42 use 6901
40 eFR 264.IB(b)
16 use 2901 et seq.
Executive Order 11988;
40 eFR 6.302
16 use 1531
Executive Order 11990;
40 eFR 6.302
!SA NeAe l3A.0009 &
.0012
ISA NeAe l3B.0500
A treatment/storage/disposal (fSD) facility must be designed, constructed, operated,
and maintained to avoid washout on a 100-year floodplain.
Requires states to identify significant habitat& and develop conservation plans for these areas.
Actions that are to occur in floodplain should avoid adverse·effecta, minimize potential harm, restore and preserve natural and beneficial value.
Requires action to conserve endangered species or threatened species, including
consultation with the Department of Interior.
Action to minimize the destruction, loss or degradation of wetlands.
Location requirements for hazardous waste treatment/storage/disposal facilities.
Siting requirements for solid waste disposal units.
May be relevant and appropriate if an onsite
TSO facility is · required 11.1 part of ove;~n
remediation and it exists within the 100-year
floodplain.
Confirmation with the responsible state agency
regarding the site being located in one of these
significant habitats is required.
Remedial actions are to prevent incursion of
contaminated groundwater onto forested
floodplain.
Endangered species, in particular the.bunched
arrowhead plant, have been identified near tho
site,
Potential remedial alternatives within wetlands.
Requirement is relevant and appropristo.
May be ~pplicablo to hazardous waste
excavated, stored, and treated onsite.
May be relevant and\ appropriate
nonhazardous waste disposed 'pnsito.
'
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-------------- --
rABLE 19 -ACTION-SPECIFIC ARARS, CRITERIA, AND GUIDANCE FOR SOIL FOR THE GE/SHEPHERD FARM SITE
Di.rposal (Onsite or Ojfsite)
Resource Conservation and Recovery Act (RCRA), as amended
Cltlssification of Hazardous Waste
Land Disposal Restrictions
Department of Transportation (DOT) Hazardous Materials
Transportation Act
Soil Treatment
Resource Conservation and Recovery Act (RCRA), as amended
Identification of Hazardous Waste
Treatment of Hazardous Waste9 in a Unit
Requirements for Generation, Storage, Transportation, and
Disposal of Hazardous Waste
Waste Piles
Tank Systems
Use and Management of Containers
Land Disposal Restrictio~s
Toxic Substances Control Act (fSCA)
PCBs Spill Cleanup Policy
42 USC Section 6901 et. seq.
40 CFR 261
40 CFR 268.10-12
40 CFR 268 (Subpart D)
49 use 1801
40 use Section 6901 et. seq.
40 CFR261
40 CFR 264.601
40 CFR264
40 CFR 264 (Subpart L)
40 CFR 264 (Subpart J)
40 CFR 264 (Subpart I)
40 CFR 268.10-12
40 CFR 268 (Subpart D)
40 CFR 700-789
40 CFR 761
Federal requirements for classification and identification of hazardous wastes.
Disposal of contaminated soil and debris resulting from CERCLA response
actions arc subject to federal land disposal prohibitions.
Regulates offsite transportation of specific hazardous chemicals and wastes.
Federal requirements for classification and identification of hazardous wastes.
Rules and requirements for the treatment of hazardous wastes.
Regulates storage, transportation, and operation of hazardous waste
generators.
Regulates storage and treatment of hazardous waste in piles
Regulates storage and treatment of hazardous waste in tank systems
Regulates storage of containers of hazardous waste
Establishes treatment standards for hazardous w"aates.
Regulations under TSCA implementing the requirements for the cleanup of spilled PCBs.
l!!!!!!!!!I -
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Applicable ' '• \ \
!ml
-- - --- - - ----- -- -
l!!!I!!!!! 1!!!11!1
rABLE 19 (Continue4) -ACTION-SPEClFIC ARARS, CRITERIA, AND GUlDANCE FOR SOIL FOR THE GE/SHEPHERD FARM SITE
Clean Air Act
Air Uso Approval
Particulate Discharge Limitations and Performance Testing
Other
Occupational Safety and Health Administration
North Carolina Hazardous Waste Management Rules
North Carolina Solid Waste Management Rules
North Cari:>lina Air Pollution Control Requirements
North Carolina Sedimentation Control Rules
North Carolina Groundwater Regulations
'
40 CFR 60 (Subpart A)
40 CFR 60 (Subpart B)
29 CFR 1910 Part 120
15ANCAC 13A
15ANCAC 13B
15ANCAC2D
15ANCAC4
15A NCAC 2L
Requires notification and performance testing by owner or operator. Relevant and Appropriate
Defines limitations for particulate emissions, test methods, and monitoring Relevant and Appropriate
requirements for incinerators.
Provides safety rules for handling specific chemicals for site workera during Applicable
remedial activities.
Siting and design requirements for hazardous waste TSDs. Relevant and Appropriate
Siting and design requirements for disposal sites. Relevant and Appropriate
Air pollution control, air quality, and emissions control .standards. Relevant and Appropriate-
Requirements for prevention of sedimentation pollution. Relevant and Appropriate
Section 106 includes requirements for tho cleanup and/or control of Relevant and Appropriate
contaminant source areas.
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111111.rLE ~Cl
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Groundwater Extraction and Treatment
Resource Conservation and Recovery Act (RCRA), as amended
Identification of Hazardous Waste
Treatment of Hazardous Wastes in a Unit
Requirements for Generation, Storage, ·
Transportation, and Disposal of Hazardous Waste
Land Disposal Restrictions
Disposal -Discharge to Surface Water!POTW
Clean Water Act
42 USC Section 6901 et. seq.
40 CFR 261
40 CFR 264.601 40 CFR 265 .400
40 CFR 263
40CFR264
40 CFR 268
33 USC Section 1351-1376
Requires use of Best Available Treatment Technology" 40 CFR 122
Requires Use of Best Management Practices 40 CPR 12S
National Pollutant Discharge Elimination System 40 CFR 122 Subpart C {NPDES) Permit Regulations
Discharge must be consistent with the requirements of 40 CFR 122 a Water Quality Management Plan approved by EPA
Discharge must not increase contaminant Section 121 (d)(2)(B)(iii) concentrations in off site surface water.
Other
Occupational Safety and Health Administration
~
North Carolina Water Quality,Standards
North Carolina Groundwater Standards
Wastewater Discharge to Surface Waters
North Carolina Air Pollution Control Requirements
29 CFR.1910 Part 120
15A NCAC 2B
15A NCAC 2L
15ANCAC2H
15ANCAC2D
Federal ·requirements for classification and identification of hazardous wastes.
Rules and requirements for the treatment of hazardous wastes.
Regulates storage, transportation, and operation of hazardous waste generators.
Prohibits dilution.as a substitute for treatment.
l!l!l!!I 11!!1!!!1
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Relevant and Appropriate
Use of best available tCChnology economically achievable is required to control· discharge of Relevant and Appropriate toxic pollutants to POTW. ;
Requires development and implementation of a Best Management Practices program to Relevant and Appropriate prevent the release of toxic constituents to surface water.
Use of best available technology economically achievable for toxic pollutants discharged to Relevant and Appropriate surface waters.
Discharge must comply with EPA-approved Water Quality Management Plan. Relevant and Approi,riate
Selected remedial action must establish a standard of control" to maintain surface water Relevant and Appropriate quality.
J>n?vj~es safety rules for handling specific chemicals for site workers during remedial Applicable actlV1hes.
Surface water quality standards.
Groundwater quality standards, regulates injection wells.
Regulates surface water discharge and discharges to POTW.
Air pollution control air quality and emis_sions standards.
.
Relevant and Appropriate
Relevant and Approprie~,
Relevant and Appropriate
Releva\t and Appropriate
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TABLE 21 -REMEDIATION GOALS FOR SOIL FOR THE GE/SHEPHERD FARM
SITE -----'
PCBs (TOTAL) 1 MG/KG 10 MG/KG OSWER DIRECTIVE
NO. 9355.4-01
TABLE 22 -REMEDIATION GOALS FOR GROUNDWATER FOR THE GE/SHEPHERD FARM.SITE
Organics
Vinyl Chloride
1,2-Dichloroethene
Chloroform
1,2-Dichloroethane
Trichloroethene
Benzene
Tetrachloroethene
Nitro benzene
Metals
Barium
Beryllium
Nickel
Lead
2.8
380
9.4
130
130
2.7
1,600
36
4,000
15
190
15
1
70
.1
I
2.8
1
I
10
2,000
4
JOO
15
CRQL (NC MCL -0.015 ug/1)
NCMCL
CRQL (NC MCL -0.19 ug/1)
CRQL (NC MCL -0.38 ug/1)
NCMCL
NCMCL
CRQL (NC MCL -0.7 ug/1)
HI=!
NCMCL
FEDMCL
FEDMCL
FEDERAL ACTION LEVEL
Manganese 5,000 50 NC MCL
11 -Hazard lndex p;1.., -North Carolina FED -Federal Safe Drinking Water Act CRQL -Contract Required Quantitation Limit MCL -Maximum Contamin~t Level ·
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Record of Decision September 1995 GE/Shepherd Fann NPL Site
be residential.
The areal extent of soil contamination above the remediation levels presented in Table 18 is
presented in Figures 24 and 25. The estimated volume of soil exceeding remediation levels at the Shepherd Farm Subsite is 6,400 cubic yards, and 3,980 at the GE Subsite.
The areal extent of groundwater contamination above the remediation levels in Table 22 is
presented in Figures 26 and 27. The estimated volume of groundwater exceeding remediation
levels at the Shepherd Farm Subsite is 6,372,000 gallons and 1,256,752,200 gallons at tl}e GE Subsite. · ·
IX. DESCRIPTION OF ALTERNATIVES
Table 23 lists the remedial action alternatives developed for the GE/Shepherd Farm Site.
The alternatives designated as "SS" are applicable to the surface soils and those designated as "GW" apply to the ground water. All the alternatives except the "No Action" alternative include
periodic monitoring of the ground water including onsite monitoring wells and potable wells for
site indicator parameters to evaluate the site conditions and the migration of chemicals over time. ·
Alternative 1 -No Action
Under the no action alternative, the site is left "as is" and no funds are expended for active control or cleanup of the surface soils and ground water. The NCP requires consideration of
this alternative as a baseline case for comparing other remedial actions and the level of
improvement achieved. However, 5-year reviews of the site, which consist of one round of
sampling selected monitoring wells and potable wells, would be conducted over an estimated 30-
year period.
Alternative 2 -Institutional Actions
This alternative consists of leaving the source areas as they are without conducting any remedial
action, with groundwater monitoring and institutional controls. This alternative includes
maintenance of a chain-link fence around the perimeter of the source areas. Annual inspection
of the fence is conducted to prevent direct exposure to impacted site soils. Repair is instituted
upon report of vandalism or other acts which result in unrestricted access. This alternative also
includes deed, permit and zoning restrictions on and near the property that prohibit excavation,
regrading, development of the site, ground-water usage, issuance of well drilling permits, or any other activities that may cause exposure to impacted soils and ground water. The 5-year
reviews would be required because concentrations of chemicals ret11ain at the site above levels
that allow unlimited use of the site.
70
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I 0 ... 0 " "' O> 0
I
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SHEPHERD FARM PROPERTY
SOIL REQUIRING REMEDIATION
1/) z
0 ~ 8 ~
(;) z ::; a. :, ~;
•
~
i5
1/)
0 w !;; z Se ;! z 0 (>
~
--------------------------l FIGURE 24
&EPA GENERAL ELECTRIC SUPERFUND SITE
EAST FLAT ROCK, NORTH CAROLINA
I I I I ~ J H 6 ~ I
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I GE PROPERTY SOIL REQUIRING REMEDIATION
•~ ~EPA CX>
GENERAL ELECTRIC SUPERFUND SITE
EAST FLAT ROCK, NORTH CAROLINA
I I \ I I , -· ~
I I
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5
I I<' . ~ I ~
I
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FIGURE_ 25
""'----'------------------------..L.----__J I
--JBZLO!O
@t
m
;i
~~
(f) z
-I fTI ;a
., )> s;: r
-I fTI r ;a fTI
00 0-1 ;,;;:::O
0
z (f) Oc ;a 7J
-I fTI I;o
o-ri ► c
;oZ
00
r Cfl z-)> -I fTI
-
.,
C)
C ;a
fTI
N O'I
(f)
I
C) fTl
:::07J o:r CfTI z ;a oo
:::!;: ;::! ►;a ri s::: ;a
7J 7J ;a ro
C7J s::: fTl fTI ;a
=<
-
'
-----
£ "' ~ /
"' _ __,.·i._ z 52 ,..,..,,.. ... ··"' ·,. " ..
/ .. ,, ... , ,·
., .... ,,-·
----
.--~!._!~-~-~----......... ,, --....,
;
r
--·--
f _,,. • "' .,.,.rm
LEGE~ll
• TEMPORARY MONITOR
WELL LOCATIONS
~ GROUND WATER PLUME
CONCENTRATIONS IN 119/L
~~
, ~C,t-~
-----.,.
---.... , .. _ --·--.......... _ .. ___
1 . 1 J VINYL CHLORIDE
1.2J CIS-1,2-DICHLOROETHENE \
0.98J IBICHLOROETHENE
29 TETAACHLOROETHENE
l!!!BI -
........
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1
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N
• • MONITOR WELL
ND • NOT DETECTED
-30--CONCENTRATIONS µg/L
APPROXIMATE SCALE -' "' ... ' ' '
IN FEET FIGURE 27
MW-30 • 200
GROUND WATER PLUME _ .
GENERAL ELECTRIC SUPERFUND SITE
EAST FLAT ROCK, NORTH CAROLINA
---· ..
1000.00
300.00
100.00
50.00
,_6_E_A_~_·. _____ --...J
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TABLE 23-REMEDIAL ACTION ALTERNATIVES FOR SURFACE SOILS AND GROUNDWATER FOR THE GE/SHEPHERD FARM SITE
Alternative 1
Alternative 2
Alternative SS3
Alternative SS4
Alternative SSS
Alternative GW6a
Alternative GW6b
Alternative GW7a
Alternative GW7b
No Action
Institutional Action
Excavation of the O to 12 inch zone of surface soils. Disposal of soils in a
RCRA Subtitle D MSWLF.
Excavation of the O to 12 inch zone of surface soils. Disposal on-site as backfill. Soils will require treatment to Remediation goals prior to disposal. Treatment
may consist of soil washing, solidification/stabilization or ex-situ bioremediation.
Containment with placement of a cap. Excavation of the O to 12 inch zone of surface soils at the Shepherd Farm Subsite. Transportation of these soils to the dry sludge impoundment area of the GE Subsite. Capping of the dry sludge
impoundment area, Landfills A and B on GE Subsite. Used in conjunction with
surface and dust control as well as diversion and collection of surface water.
Pump and treat affected ground water. Treatment may include filtration, air
stripping, GAC adsorption or oxidation. Discharge treated ground water on site
via surface water.
Pump and treat affected ground water. Treatment may include filtration, air
stripping·, GAC adsorption or oxidation. Discharge treated ground water off site
via POTW.
Gfound-~ater treatment consisting of a combination of in-situ bioremediation and
ex-situ treatment as noted in Alternative GW6. Discharge treated ground water
on site via surface water.
Ground-water treatment consisting of a combination of in-situ bioremediation and
ex-situ treatment as noted in Alternative GW6. Discharge treated ground water
off site via POTW.
AJ.l the alternatives except 1 include periodic monitoring of the groundwater for site indicator parameters to eValuate the site conditions and the migration of chemicals over time.
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Alternative SS3 -Excavation; Off-site Disposal
This alternative requires the excavation of the surficial soils at the site which are impacted at concentrations exceeding the Remedial Action Goals and disposal off-site in a RCRA Subtitle D Municipal Waste Landfill (MSWLF). Surficial soils are defined as the zone from O to 12 inches below grade. The excavation area is backfilled with clean fill soil. This alternative will prohibit direct contact with the contaminants.
Construction of a temporary fence will be required around the excavation. Air quality monitoring shall be conducted at the perimeter of the excavation site.
Alternative SS4 -Ex-Situ Treatment; On-site Disposal
Alternative SS4 is similar to alternative SS3, except that the soils are treated to the RAO's of the site and disposal may occur on-site as backfill. Treatment processes may include soil washing, solidification/stabilization, or ex-situ bioremediation.
Soil washing uses water and mechanical action to remove the contaminants that adhere physically to the soil particles. Surficial contamination is removed from the coarse fraction of the soils by . abrasive scouring. The wash water may be augmented with a leaching agent, surfactant, pH adjustment, or chelating agent to help remove organics or heavy metals. The spent wash water requires further treatment, after which it is recycled back to the treatment unit. The contaminated silt/clay fraction also requires further treatment which may consist of solidification/
tabilization. Bench scale testing will need to be conducted to verify the efficiency of the option.
Solidification/stabilization consists of excavating the surficial soils and mixing the soils with cement and additives in a conventional concrete mixing plant. The mixture would then be replaced in the ground in I-foot lifts and finally rolled into compaction. Bench-scale testing should be conducted to evaluate the soil cement concrete. The soil cement should be analyzed for TCLP constituents. Since this option does not reduce the level of contaminants, and requires strict deed controls, disposal would occur at the GE property.
Ex-situ bioremediation involves slot excavation of the soil in strict sequence and may consist of placement of the soil in a treatment facility on-site. The treatment facility may consist of a plastic film greenhouse enclosure, a soil treatment bed consisting of an engineered clay liner 12 inches thick and a drainage system to control water movement, a spray system for distributing
water, nutrients and inocula, an organic vapor control system consisting of activated carbon absorbers, and a fermentation vessel for preparing microbial inoculum or treating contaminated leachate for the backfill soils. If organic ·vapors are not a problem, the plastic greenhouse enclosure and the organic vapor control system is not necessary. TQ_e contaminated soils would
be placed ori the treatment bed in approximately 12 to 15 inch lifts, and soil conditions would
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be optimized for biological activity by daily tilling and by maintenance of the appropriate soil
moisture content. The soils. during treatment should be sampled weekly and analyzed for
residual contamination. Bench scale testing will need to be conducted to verify the efficiency
of this option.
Alternative SSS -Containment
This alternative consists of capping used in conjunction with storm water management and dust
control. Capping involves the installation of an impermeable layer over the area of contan_ijnated
soil and development of a storm water management system to route storm water off the· cap in
· an acceptable manner. The top foot of contaminated soil at the Shepherd Farm subsite would
be excavated and transported. to the GE Subsite dry sludge impoundment area. The dry sludge
impoundment, Landfill A and Landfill B would be capped as described above. Because
portions of Landfills A and B are already paved with asphalt, asphalt is considered the most
appropriate capping material. Deed restrictions will be required to limit the use of the site and
prevent subsurface development. Annual inspection and maintenance of the containment area
will be required.
Alternative GW6a -Ex-Situ Treatment; On-site Discharge
. As part of this alternative, the existing extraction well system would be utilized in conjunction
with additional extraction wells. Groundwater would be extracted from both the Shepherd Farm
Subsite and the GE Subsite. The extracted ground water would be pumped to an on-site
treatment facility. The treated ground water would then be discharged to Bat Fork Creek. The process options for treating the VOC's in the ground water include: air stripping, granulated
activated carbon (GAC) adsorption or oxidation/UV photolysis. If metals are detected in the
effluent at concentrations above the discharge limitations, a process option to remove metals will
have to be added into the treatment train. Also, to protect and keep the air stripper functional,
the ground water may need filtering prior to treatment.
The existing treatment system is composed of extraction wells, a 10,000-gallon equalization tank, an air stripping tower (currently not present onsite), and associated piping and pumps with
discharge to Bat Fork Creek. This is a unit operation in which a: volatile component of a
solution is transferred into a gas phase. The system used for continuously contacting a liquid
and a gas (air) stream may be a tower filled with irregular solid packing material, an empty
tower into which the liquid is sprayed, or a tower containing a number of bubble cap or sieve
plates. Generally, air and liquid streams flow counter-currently through the contacting towers
in order to achieve the greatest rate of stripping. The efficiency of the air stripping process is mainly dependent on the air-to~water ratio, the contact time, the temperature and the physical and chemical properties of the constituents of concern. _ .
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Record of Decision
September 1995 GE/Shepherd Farm NPL Site ---Only one treatment system would be utilized. Groundwater extracted from the Shepherd Farm Subsite would be piped to the treatment system located on the GE Subsite.
Bench and/or pilot studies would have to be conducted to determine if the liquid effluent would have to undergo further treatment prior·to discharge. The vapor effluent, off-gas, would have to undergo additional treatment to destroy or remove the contanlinants stripped from the ground water prior to being discharged to the atmosphere. The off-gas may be treated by GAC adsorption. The GAC adsorption would consist of down-flow carbon beds connected in series. Pilot studies would have to be performed to determine the optimum feed rates, number of columns and contact time.
The oxidation/UV photolysis process involves the use of ultraviolet light to catalyze the chemical oxidation of organic contaminants in water by its combined effect upon organic contaminant and its reaction with either hydrogen peroxide or ozone. The UV oxidizer reaction results in the formation of hydroxyl radicals, which then react with organic contaminants in water.
Any sludge generated will have to be tested for TCLP parameters prior to disposal as either a soil or hazardous waste. The spent GAC may be either transported off-site for regeneration at a permitted facility or disposed at a permitted facility. The spent GAC is considered a hazardous waste .and is subject to RCRA recycling regulations.
Alternative GW6b -Ex-Situ Treatment; Off-Site Discharge
Alternative GW6b is identical to alternative GW6a, except that the treated ground water would be discharged to the local POTW. Discharge criteria would be set by the POTW.
Alternative GW7a -Groundwater Treatment; Gradient Control; On-Site Disposal
Alternative GW7a consists of both in-situ and ex-situ groundwater treatment, extraction wells, an infiltration gallery, and on-site discharge of treated water. The unit processes involve constructing infiltration trenches on the Shepherd Farm and GE Subsites at appropriate locations which would be used to introduce microorganisms, nutrients and oxygen (if aerobic). This system would require a source of water and a holding/mixing tank for combining the water, nutrients and oxygen source prior to introduction into the aquifer through the infiltration gallery. Extraction wells would be installed around the perimeter of the contaminant plume and in the source areas as well as down gradient of the infiltration trenches. A significant advantage of this alternative is that the extraction wells would provide gradient control. The extracted ground water would be treated in accordance to the ex-situ treatment options presented in Alternative GW6a. · The treated water may be discharged either to Bat Fork Creek or used as a source of water in the in-situ treatment of the groundwater. _
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In-situ bioremediation is \ISed in conjunction with the ex-situ treatment to degrade the
contaminants of concern in the aquifer because "conventional" pump and treat methods generally
fail to remove the fraction of organic contaminants which are adsorbed to the organic and
mineral components of the aquifer matrix. This contaminant fraction may be unrecoverable
using standard pumping methods and will continue to slowly solubilize into the ground water.
Bioremediation schemes attempt to either stimulate naturally occurring aerobic or anaerobic .
microorganisms to degrade contaminants in°situ, or introduce microorganisms capable of
degrading the contaminants. Typically, biodegradable contaminants can be degraded at rates
which are orders of magnitude greater than the leaching rate of the contaminants in an ~quifer
system, provided growth limiting nutrients and oxygen are added. Bench testing must be
conducted to verify the efficiency of this system and to determine whether aerobic or anaerobic
bioremediation would provide the optimum remediation of site contaminants. In addition, deed,
permit and zoning restrictions on and near the property may be enacted during the remediation.
process.
Alternative GW7b -Groundwater Treatment; Gradient Control; Off-Site Disposal
This alternative is similar to alternative GW7a except that the treated water would be discharged ·
to the local POTW.
X. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
In this section, each alternative is assessed using seven evaluation criteria required under
CERCLA. Comparison of the alternatives with respect to these evaluation criteria are presented
in summary form. This approach is designed to provide sufficient information to adequately
compare the alternatives, aid in the selection of an appropriate remedy for the site, and
demonstrate satisfaction of the statutory requirements upon preparation of the Record of Decision
(ROD).
Each alternative is evaluated in terms of its ability to:
• Be protective of human health and the environment.
•
•
•
Attain ARARs or provide grounds for invoking a waiver .
Use permanent solutions and alternative treatment technologies or resource
recovery technologies to the maximum extent practicable.
Satisfy the preference for treatment that reduces toxi,£_ity, mobility, or volume of
the hazardous substances, pollutants and contaminants as a principal element.
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• Be cost-effective .
The seven evaluation criteria required to address the above CERCLA requirements serve as the .
basis for conducting the detailed analysis. The evaluation criteria are briefly described below.
1.
2.
3.
4.
5.
6.
7.
Overall Protection of Human Health and the Environment determines whether
each alternative meets the requirement that it be protective of human health and
the environment in both the short-and long-term, from unacceptable risks posed
by hazardous substances, pollutants, or contaminants. This criterion is qf key
importance. While the remedy selected may on occasion seek a waiver of a given
ARAR, the remedy selected must be protective of human health and the
environment.
Compliance with ARARs is used to determine how each alternative complies with
federal and state ARARs as defined in CERCLA Section 121, as discussed in
Section 3, or provide grounds for invoking one of the waivers.
Short-Tenn Effectiveness addresses the impacts of the alternatives during the
construction and implementation phase until remedial response objectives have
been met. Alternatives are evaluated with respect to their short-term effects on
human health and the environment.
Long-Tenn Effectiveness and Permanence addresses the results of a remedial ·
action in terms of the risk remaining at the site after response objectives have
been met. The primary focus of this evaluation is the effectiveness of the
controls that will be applied to manage risk posed by· treatment residuals or
untreated wastes.
Reduction of Toxicity, Mobility, and Volume addresses the statutory preference
for selecting remedial actions that employ treatment technologies that permanently
and significantly reduce toxicity, mobility, or volume of the hazardous substance
as their principal element. This preference is satisfied when treatment is used to
reduce the principal threats at the site through destruction of toxic contaminants,
irreversible reduction in contaminant mobility, or reduction of total volume of
contaminated media.
Implementability addresses the technical and administrative feasibility of
implementing an alternative and the availability of various services and materials
required during its implementation.
Cost estimates for the FS are expected to provide an order-of-magnitude
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September 1995 .,. ------·-
evaluation for comparison of alternatives and are based on the site
characterization developed in the RI. Capital cost, annual cost, and a present
worth analysis are part of this evaluation. The present worth represents the
amount of money that, if invested in the initial year of the remedial action at a
given rate, would provide the funds required _to make future payments to cover
all costs associated with the remedial action over its planned life. The baseline
present worth is computed at a discount (interest) rate of 7 percent over a 30 year
period. Appendix A contains spreadsheets showing each component of the present
worth costs.
The first two criteria are referred to in the RI/FS guidance manual (EPA 1988) as the "threshold
factors", implying that for further consideration of an alternative, these two criteria must be
satisfied. Alternatives which do not satisfy these threshold factors are not feasible (40 CFR
300.430(f)(l)(I)(A). Criteria 3 through 7 are referred to as "primary balancing factors" (page
4-25 of RI/FS manual), implying that these criteria are used to select the alternative among the
feasible alternatives. Criteria 3 through 5, however, are also measures of the effectiveness and
are used accordingly. There are two other criteria, state acceptance and community acceptance,
which are provided by state and local agencies and the public. These criteria will be evaluated
in the responsiveness summary. A detailed evaluation of the alternatives using the above criteria
is presented below.
Alternative 1 -No Action
Section 300.430-(e) of the NCP requires that the "no action" alternative be carried forward for
consideration in the detailed analysis of alternatives as a baseline. for comparison of the other
alternatives. Under the no action alternative, funds are not expended for control or cleanup of
surface soil or ground-water contamination associated with the GE Site .
Overall Protection of Human Health and the Environment
This alternative would not provide any increased protectii:m to human health or the environment.
If no action is taken, contaminants in the source areas would remain and continue to leach into
ground water. No remediation efforts have been conducted in the two landfill areas at the GE
site or the Shepherd Farm property, both of which are contaminated with PCB's. These
contaminants would not be expected to decrease significantly with time due to the very slow rate
of degradation. GE reports that all USTs and contaminated soils associated with the USTs have
been removed, as well as all of the soils associated with the ruptured drain line. Since these are
suspected to be the main sources associated with the VOC contamination in the groundwater and
they have been removed, the concentration of contaminants in the ground water would continue
to decrease with time due to natural attenuation and degradation. _However, under this action
monitoring or verification of the decrease would be conducted at the 5-year review stage.
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Compliance with ARARs
· The "no action" alternative would not address compliance with ARARs since there would be no
active measures taken to reduce the contaminant concentrations. The volatile contaminant
concentrations would be expected to decrease with time ... due .. to natural attenuation and
degradation. Location-and action-specific ARARs do not apply to this alternative since further
remedial actions would not be conducted.
Short-Term Effectiveness
Because no activities would be implemented, there would be no additional· impact on the
community. Also, no construction or operation related-impacts to the environment would occur,
since no site activiti.es would be performed.
Long-Term Effectiveness· and Permanence
Because remedial actions would not occur, this alternative would not provide any long-term
effectiveness or permanence. The long term risks of exposure of on-site receptors to the
contaminated surface soils and ground water would not be addressed. However, since the
suspect sources of ground water contamination have been removed, the concentration of
contaminants in the ground water would be expected to decrease with time due to natural
attenuation and degradation. The areas contaminated with PCB's would not be expected to
decrease significantly with time due to the very slow rate of degradation.
Reduction of Toxicity, Mobility, and Volume
The "no action" alternative would provide no reduction in toxicity, mobility, or volume of
contaminated media.
Implementability
This criterion is not applicable because remedial activities would not occur.
Cost
The cost of this alternative consists only of 5-year review expenses. The total present worth cost
for this alternative is approximately $160,211. The estimated annual operation and maintenance
cost is approximately $21,800. Total capital costs are estimated to be $0.
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GE/Shepherd Farm NPL Site ----Alternative 2 ~ Institutional Action
This alternative includes access restrictions and monitoring to protect human health and the
environment. Under this alternative, no source control remedial measures will be undertaken
at the GE site. Five-year reviews are required under the NCP to determine if contaminants
which remain on-site are causing additional risk to human health or the environment. As a
result of this review, EPA will determine if additional site remediation is required. Five-year
reviews are assumed to be conducted for a JO-year period.
Overall Protection of Human Health and the Environment
Institutional controls would limit exposure to on-site soils by restricting access; however, the
restrictions would · not eliminate the risk of exposure or control the plume migration.
Consequently, this alternative would not provide active protection of human health and the
environment, although monitoring would reveal future threats to human health and the
environment.
Compliance with ARARs
This alternative does not achieve the remedial action objectives or chemical-specific ARARs
established for surface soil and groundwater. Through natural attenuation and degradation, a
decrease in the contaminant concentration would be expected with time. However, the
magnitude of the decrease can only be qualitatively determined. It is not known whether natural
attenuation and degradation would result in sufficient contaminant reduction to attain ARAR's.
Location-and action-specific ARARs do not apply to this alternative since further remedial
actions of an intrusive nature would not be conducted.
Short-Tenn Effectiveness
Institutional controls could be implemented in approximately one year. Ground water and soil
monitoring could begin immediately. No significant environmental impacts would be expected
during the sampling events. The surrounding community and workers would be protected by
restricted access to the contaminated media, provided the restrictions are complied with.
Long-Tenn Effectiveness and Permanence
Properly implemented institutional controls would prevent ingestion and direct contact with
contaminated media, thereby reducing risk to potential users. Implementation of institutional
controls with continued monitoring would be required indefinitely. The long term monitoring
results and the actual effectiveness of the institutional controls would require periodic
reassessment to determine the continued effectiveness of this alternative. If the degree of
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protectiveness to human health is insufficient, further remedial actions would have to be
implemented.
Reduction of Toxicity, Mobility, and Volume
This alternative would not actively reduce the volume, toxicity or mobility of the contaminants
of concern. The size of the contaminant plume could increase with time. However, as the size of the plume increases, the contaminant concentrations would decrease via natural attenuation
and degradation.
Implementability
This alternative would be readily implemented since there are no remedial activities of an
intrusive nature being performed. The implementation of monitoring would present no difficulties. Implementing and enforcing deed restrictions would require the cooperation of the state and county governments. Institutional controls are subject to change in legal and political
interpretations over time. The attachment of deed restrictions to the GE Subsite can be readily
implemented. Voluntary acceptance by adjacent property owners is questionable. Consequently,
present or future property owners could choose to ignore or be unaware of the use restrictions.
The restrictions could also be lost during future property transfers. For the above reasons, the
reliability of ground water use restrictions is considered uncertain. Legal services, field personnel and analytical laboratories necessary for implementation of this alternative are readily
available. If additional monitor wells are required, well drilling services are readily available.
Monitor equipment is readily available for groundwater sampling. Long-term maintenance and
possible future replacement of the . fence and signs would be required but also could be
implemented with some ease.
Cost
The total cost for this alternative consists of deed restrictions, permit restrictions, and ground-water monitoring only; no treatment is included. The total present worth cost for this alternative
is approximately $346,362. The estimated annual operation and maintenance cost is
approximately $24,300. Total capital costs are estimated to be $100,750.
Alternative SS3 -Excavation; Off-Site Disposal
This treatment alternative involves excavating the contaminated surficial soils which exceed the
Remediation Goals and disposal in a RCRA Subtitle D Municipal Solid Waste Landfill. The
excavation is backfilled with clean fill soil, and the area is revegetated. -. Overall Protection of Human Health and the Environment
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This alternative would provide increased protection of human health and the environment
through the removal of the organic chemicals which exceed EPA's Remediation Goals. This
alternative will virtually eliminate the risks associated with the exposure pathways and greatly
reduce the potential risk of surface soil ingestion, inhalation, and dennal contact.
Compliance with ARARs
This alternative will comply with the chemical-, location-and action-specific ARARs.
Short-Tenn Effectiveness
Achievement of short-tenn effectiveness will require special construction procedures and controls
to ensure that human health and the environment are adequately protected during the excavation
operation. The primary exposu~ route is through dust emissions. Air monitoring will be
necessary to ensure that a safe working environment is maintained and that no threat to human
health and the environment is created by air emissions. However, direct exposure can also occur
during loading, hauling and disposal. Also, impact due to noise, truck traffic, and other
activities will have to be controlled. This exposure and impact can be limited as the alternative
is highly utilized and well proven.
Long-Tenn Effectiveness and Permanence
This alternative is completely effective because it provides for removal of contaminated soil such
that the Remediation goals are met for surface soils. The removed soils will be disposed of off-
site and replaced with clean backfill.
Reduction of Toxicity, Mobility, and Volume
Contaminated surface soil will be excavated and disposed of in a Subtitle D Municipal Solid
Waste Landfill. Off-site landfill disposal will reduce the mobility of contaminants, but the
volume and toxicity remain the same.
Implementability
As with short-term effectiveness, this technology has been demonstrated to be readily
implementable because it utilizes well proven equipment and construction methods, providing ·
it is well planned and supervised.
An estimated four months will be required for contractor selection. The actual implementation
of the alternative, including site preparation and excavation, may~ an additional two months.
Therefore, assuming that weather conditions do not cause extreme delays, this alternative could
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be implemented in approximately six months.
An engineering consideration for the excavation and off-site disposal of the contaminatP.d surface
soil is that all permits and licenses must be obtained and/or validated before off-site transport.
The major system components, construction equipment, and materials required for operations
under this alternative include
• contractor's temporary facilities and utilities;
• bulldozer;
• backhoe;
• front-end loader;
• dump trucks with liners and tatps for transportation of soil;
• backfill for excavated areas; and
• hydroseeding equipment.
Cost
The total present worth cost for this alternative is approximately $1,524,235. The estimated
annual operation and maintenance cost is approximately $0. Total capital costs are estimated
to be $1,524,235.
Alternative SS4 -Ex-Situ-Treatment; On Site Disposal
This alternative consists of excavation and treatment of contaminated soils to the RAO' s of the I site and disposal on-site as backfill.
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Overall Protection of Human Health and the Environment
This alternative would provide an increased protection of human health and the environment
through the excavation and treatment of the contaminated surface soils, and will eliminate the
risks associated with the exposure pathways.
Compliance with ARARs
This alternative will comply with the chemical-, location-and action-specific ARARs.
Short-Term Effectiveness -. Achievement of short-term effectiveness will require special construction procedures and controls
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to ensure that human health and the environment are adequately protected during the excavation
operation. The primary exposure mute is through dust emissions. However, direct exposure
can also occur during loading, hauling and disposal. In addition, impact due to noise, truck
traffic, and other activities will have to be controlled.
Long-Term Effectiveness and Permanence
This alternative is completely effective because it provides for excavation and treatment of
contaminated soil. If the soil is treated such that the RAO's are achieved, then the soil ytill be
suitable for backfill. ·
Reduction of Toxicity, Mobility; and Volume
The alternative reduces the mobility and toxicity of soil contamination at the site through on-site
treatment. The volume also will be reduced unless solidification/ stabilization is part of the
treatment process. In this case, the volume of the treated material may increase depending on
the type of stabilizer used.
Implementability
The bench-scale studies of the treatment system will require approximately three months and the
design of the treatment system will require approximately three months. An estimated six
months will be required for contractor selection. The actual excavation and treatment of
contaminated surface soil may take another six months. Therefore, assuming that weather
conditions do not cause extreme delays, this alternative could be implemented in approximately
1.5 years.
The major engineering considerations in implementing the excavation and on-site treatment
system include ..
•
•
design of soil staging area;
bench-scale testing; and
design and installation of treatment option .
The major system components, construction equipment, and materials required for operations
under this alternative include
• •
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contractor's temporary facilities and utilities;
bulldozer;
· backhoe· . '
front-end loader;
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dump trucks;
treatment units;
backfill for excavated areas (if necessary); and
hydroseeding equipment .
September 1995
Monitoring the operation of the treatment system would be required to verify that the treated soil
meets the anticipated remediation goals. Determination of the soil leaching potential by TCLP
testing would be required before on-site disposal for compliance with RCRA and state
regulations.
Cost
The total present worth cost for the solidification/ stabilization option in this alternative is
approximately $3,040,287. The estimated annual operation and maintenance cost is
approximately $118,400. Total capital costs .are estimated to be $2,288,472. Detailed cost
estimates are presented in Appendix A. ·
The total present worth cost for soil washing option in this alternative is approximately
$4,174,375. The estimated annual operation and maintenance cost is approximately $118,400.
Total capital costs are estimated to be $3,422,560. Detailed cost estimates are presented in
Appendix A.
The total present worth cost for the bioremediation option in this alternative is approximately
$1,955,437. The estimated annual operation and maintenance cost is approximately $118,400.
Total capital costs are estimated to be $1,203,622. Detailed cost estimates are presented in
Appendix A. ·
Alternative SSS -Containment
The primary objective of this alternative is to eliminate the mobility and exposure pathways of
site chemicals by containment. Containment is achieved by capping. A storm water
management system will be required to reduce surface water impacts. Short term dust and vapor
controls will be required during construction activities. This alternative also includes monitoring
and access restrictions.
Overall Protection of Human Health and the Environment
This alternative results in protection of human health and the environment by preventing direct
exposure to impacted soils and by preventing off-site migration of chemicals in the surface soils.
Compliance with ARARs
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This alternative will meet site-specific ARARs because this alternative will prevent direct contact
with the soils.
Short-Term Effectiveness
Achievement of short-term effectiveness will require special construction procedures and controls
to ensure that human health and the environment are adequately protected during the construction
operations. The primary exposure route is through dust emissions. However, direct exposure
can also occur during loading, hauling and disposal. Also, impact due to noise, truck traffic,
and other activities will have to be controlled. This exposure and impact can be limiteci"as the
alternative is highly utilized and well proven.
Long-Term Effectiveness and Permanence
This alternative requires regular maintenance and continued implementation of access restriction
to assure long-term effectiveness. Capping does not provide an ultimate permanent remedy but
should be considered of long duration for comparative purposes. Since contaminated soil
remains on-site, 5-year reviews over an estimated 30-year period would be required to ensure
that this alternative provides adequate protection of human health and the environment under·
CERCLA 121(c).
Reduction of Toxicity, Mobility, and Volume
This alternative eliminates migration of constituents from the site area and thus reduces the
mobility of site chemicals. The toxicity and volume of the impacted source soil will essentially
remain unchanged.
Implementability
An estimated three months will be required for contractor selection. The actual implementation
of the alternative, including site preparation and construction of the cap, may take another three
months. Therefore, assuming that weather conditions do not cause extreme delays, this
alternative could be implemented in approximately six months. This alternative could take more
time to implement if it is difficult to obtain the necessary deed restrictions.
The major engineering considerations for capping include
• design of stormwater collection system;
• anticipated service life of the cap;
• cap thickness and infiltration potential;
• replacement schedule; and
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Record of Decision September 199S GE/Shepherd Farm NPL Site ---• effects of environmental factors on the cap .
The major system components, construction equipment, and materials required for operations
under this alternative include
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• •
contractor's temporary facilities and utilities;
asphalt;
backhoe;
bulldozer;
front -end loader;
dump trucks with liners and tarps for transportation of soil;
backfill for excavated areas; and
hydroseeding equipment.
The cap would be inspected on a regular basis for signs of erosion, settlement, or subsidence.
Institutional controls consisting of deed restrictions to protect the integrity of the cap system, and long-term groundwater monitoring would apply.
Cost
The total present worth cost for this alternative is approximately $855,297. The estimated
annual operation and maintenance cost is approximately $6,200. Total capital costs are
estimated to be $777,426.
Alternative GW6a -Ex-Situ Treatment; On-Site Discharge
This alternative involves using the existing extraction well system. The extracted ground water would be pumped to an on-site treatment facility. The treated ground water would then be
discharged to Bat Fork Creek. The operation of the ground water extraction and treatment
system would continue until the remedial action objectives are achieved.
Overall Protection of Human Health and the Environment
As long as the groundwater extraction system is in operation, this alternative will eliminate the
exposure pathways and greatly reduce the potential risk of groundwater ingestion and inhalation
of volatiles. Additionally, contaminated groundwater will be contained so that downgradient
wells would not become contaminated through continued migration of contaminants. However,
if groundwater extraction is halted before remediation goals are obtained, contaminated
groundwater will no. longer be contained, and exposure pathways associated with continued
contaminant migration in groundwater may emerge again.
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Compliance with ARARs
Groundwater extraction will act to decrease contaminant concentrations in groundwater by
removing contaminants from the aquifer system,· and is thus potentially effective in achieving
chemical-specific ARARs within a reasonable timeframe. Air quality and emission standards
will have to be met since there will be an on-site treatment system. The treated water needs to
meet all effluent requirements and ambient water quality criteria before discharge to Bat Fork
Creek. Location-specific ARARs will have to be considered during the remedial design,
particularly with regard to the installation of the treatment system. Specifically, citinKpf the
treatment system will be in an area that is protective of the wetlands and outside of the ld0-year
floodplain. Significant habitats will have to be identified and the presence of endangered species
needs to be confirmed before any remedial action takes place. Specifically, the bunched
arrowhead plant, which has been identified as an endahgered plant and is located near the site,
will have to be protected during extraction of groundwater. In addition, the impacts on the East
Flat Rock Bog remnant in the GE site vicinity arid the King Creek Bog in the Shepherd Farm
Site vicinity need to be considered. These bogs have been identified as priority areas of national
significance and also may be negatively impacted by groundwater extraction. Action-specific
ARARs also will have to be considered, including discharge to a surface water body.
Short-Term Effectiveness
Construction operations associated with this remedial alternative would produce limited
disturbance to the surrounding community. All treatment facilities would be located on the GE
site within the fenced area. Proper operation of the treatment system would result in no
atmospheric discharges of VOC's. An effluent discharge monitoring station for treated ground
water would provide a check on the effluent quality prior to discharge. Continued monitoring
of the ground water would provide a check on the plume movement and provide evidence of
progress in attaining remedial goals.
Long-Term Effectiveness and Permanence
The long term effectiveness and permanence of this alternative depends on the effectiveness of
the ground water extraction mechanism in removing the contamination from the aquifer.
Contaminants of concern adsorbed to the aquifer matrix and released very slowly could result
in the inability of this alternative to achieve the remedial goals. The major long term control
required to remediate the ground water will be the continued operation and maintenance of the
extraction well(s) and the treatment system. The operation and maintenance of the well(s) and
treatment will include repair/replacement of pumps and piping, purchase of chemicals,
regeneration of GAC and replacement of UV bulbs. Long term monitoring of the ground water
would be effective in tracking the nature and extent of contaminati_on and the effectiveness of
the treatment unit. Sampling the existing monitor well network would indicate if contaminants
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Record of Decision September 1995 GE/Shepherd Farm NPL Site
are migrating from the extraction capture zone. Long term controls would be limited to
continued ground water monitoring ..
Reduction of Toxicity, Mobility, and Volume
The various unit processes in the treatment system will provide for the degradation or destruction
of a significant portion of all of the contamination in the ground water. Using conventional
ground water extraction methods, a portion of the contaminants of concern will remain adsorbed
to the organic and mineral components of the aquifer matrix after pumping for long periods of time. These contaminants will tend to slowly solubilize back into the ground water indefiiiitely.
However, the majority of the plume could be captured for treatment. The ground water would
be treated to achieve the MCL's for the contaminants of concern.
Implementability
This system could easily be implemented on the site. The unit processes of the treatment system
are commercially available and have been demonstrated to be effective on the contaminants of concern. Pilot scale treatability studies would be required to develop specific design parameters
and confinn the systems effectiveness in treating the contaminants of concern. It is anticipated
that the existing system would be incorporated into the design.
The administrative requirements for this alternative are minimal; these include compliance with
teciutj.cal NPDES requirements, established by EPA and North Carolina, for discharge of treated
ground water on site. The unit process for the treatment system, and required contractors and
equipment are readily available. Prior to development of the extraction system, additional
aquifer testing would be required to fully characterize the aquifer. Aquifer modeling would also
be required to determine locations and depths of any additional wells needed, and the most
effective pumping rates.
An estimated six to nine months will be required for design and contractor selection. The actual
implementation of the alternative, including site preparation and installation of any additional
components to the existing treatment system (i.e., air stripper), may take another three months.
Therefore, assuming that weather conditions do not cause extreme delays, this alternative could be implemented in approximately 1 year.
The major engineering considerations in implementing the groundwater and discharge systems · include ·
•
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•
testing of the existing extraction well system;
potential for well plugging (reduction in flows) over time; _ .
monitoring requirements;
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•
cleanup verification;
piping of extracted water to the treatment system;
piping of treated water to Bat Fork Creek; and
NPDES permit requirements .
September 1995
The major engineering considerations in implementing the groundwater treatment system include
• design flow;
• permit requirements;
• pilot studies for treatment processes;
• citing and design of treatment units;
• monitoring the effluent water quality for surface water discharge;
• implementing treatment option for off gas from· the air stripper;
• monitoring the effluent air quality from the air stripper; and
• process effectiveness monitoring.
The major system components, construction equipment, and materials required for operations
under this alternative include
•
•
•
•
contractor's temporary facilities and utilities;
additional process units for the existing groundwater treatment system;
pumping, piping, fittings, and valves for fluids transport; and
system instrumentation and controls .
Long-term groundwater monitoring for cleanup verification purposes and to track contaminant
plume migration would be required under this alternative. Samples would be collected from
selected existing wells and analyzed for the site indicator parameters.
The groundwater treatment system also would require monitoring and maintenance during its
approximate 30-year operational life. Monitoring of the treatment system would include periodic
sampling of the influent and effluent from the treatment system and analysis in accordance with
NPDES discharge permit requirements. Sample collection is assumed to be on a weekly basis.
Maintenance of the extraction and treatment systems would be performed in accordance with
operation and maintenance requirements developed after equipment specification and
procurement are completed. At a minimum, it is expected that regular periodic maintenance
would be required on the submersible pumps, valves, and fittings of fluids piping systems, as
well as on the treatment system to ensure its efficient operation.
Operation and maintenance of the treatment system would be con'1ucted by a contractor who
would be responsible for continuous operation and maintenance of the process. Process control
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GE/Shepherd Farm NPL Site
would be automated as much as possible with the contractor stopping by periodically to checkup
on the system. ·
Cost
The total present worth cost for this alternative is approximately $5,328,398. The estimated
annual operation and maintenance cost is approximately $273,285. Total capital costs are
estimated to be $1,166,750.
Alternative GW6b -Ex-Situ Treatment; Off-site Discharge
Alternative GW6b is identical to alternative GW6a, except that the treated ground water would
be discharged to the local POTW. .
Overall Protection of Human Health and the Environment
This alternative would provide increased protection of human health and the environment
through extraction and treatment of contaminated ground water.
Compliance with ARARs
This alternative is expected to comply with all ARARs. The ground water would have to be
treated to the POTW permit requirements.
Short-Term Effectiveness
The short term effectiveness of this alternative is similar to alternative GW6a. Minimal
disturbance is expected.
Long-Term Effectiveness and Permanence
This alternative would provide the same degree of long term effectiveness and permanence as
alternative GW6a. Long term controls would be limited to continued ground water monitoring.
Reduction of Toxicity, Mobility, and Volume
This alternative would provide the same reduction of toxicity and volume as alternative GW6a.
Implementability
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----·· The implementability of this alternative would be the same as alternative GW6a.
Cost
September 1995
The total present worth cost for:this alternative is approximately $6,076,336. The estimated
annual operation and maintenance cost is approximately $295,085. Total capital costs are
estimated to be $1,166,750.
Alternative GW7a -Ground-water Treatment; Gradient Control; On Site Discharg_e
Alternative GW7a involves the use of in-situ bioremediation to degrade the contaminants of
concern in the aquifer. The process involves installing up gradient infiltration trenches at an
appropriate location which would be used to introduce microorganisms, nutrients and an oxygen
source (if aerobic). This system would require an external source of water and a holding/mixing
tank for combining the water, nutrients and oxygen source prior to infiltration into the aquifer.
Overall Protection of Human Health and the Environment
This alternative would provide significant protection of human health and the environment
through expedited ground water remediation (as compared to pump and treat). No adverse
health effects are anticipated to result from the growth of indigenous microorganisms under this
alternative. In fact, after active remediation is ceased, microorganisms would be available to
degrade any residual contamination in the aquifer.
Compliance with ARARs
The in-situ bioremediation process would be designed to meet the remedial goals for the GE site
and the process would be continued until the goals were attained.
Short-Term Effectiveness
Short term risks would be similar to those discussed for the two previous remedial alternatives.
No adverse environmental impacts are anticipated. ·
Long-Term Effectiveness and Permanence
This alternative would be effective in achieving permanent remediation of the contaminated
ground water plume. Any residual contamination remaining after cessation of active remediation
would continue to be degraded until the contaminant, oxygen and nutrient supply is depleted.
Long term controls would be limited to continued ground water 111!1nitoring.
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Reduction of Toxicity, Mobility, and Volume
The in-situ bioremediation technology used in this alte.mative would be effective in permanently
reducing the mobility, toxicity and volume of contamination. The concentration of contaminants
would be reduced to enforceable drinking water standards:· With the reduction of contaminant
concentrations, the volume of the plume would decrease throughout the removal action.
Implementability
The technical feasibility of enhanced bioremediation of VOC's is documented in full-scale
remediation projects and field treatability studies. In-situ bioremediation is most successful at
sites with moderate to high permeability and a shallow zone of contamination. Prior to
development of the infiltration system, additional aquifer tests would be required to fully
characterize the aquifer, and to determine the most effective infiltration rates.
An estimated six to nine months will be required for design and contractor selection. The actual
implementation of the alternative, including site preparation, construction of the infiltration
trenches, and installation of the mixing system, may take another three months. Therefore,
assuming that weather conditions do not cause extreme delays, this alternative could be
· implemented in approximately 1 year.
The major engineering considerations in implementing the in-situ groundwater treatment system
include
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•
pilot study for biotreatment process;
· citing and design of the mixing system and infiltration trenches;
monitoring the effluent water quality from the mixing tank before discharging to
. trenches;
process effectiveness monitoring; and
cleanup verification .
The major system components, construction equipment, and materials required for operations
under this alternative include
•
•
•
•
contractor's temporary facilities and utilities;
process unit for the in-situ groundwater treatment system (i.e, mixing tank and nutrients);
water source for the mixing system; and
system instrumentation and controls .
Long-term groundwater monitoring for cleanup verification purpo~s and to track contaminant
plume migration would be required under this alternative. Samples would be collected from
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GE/Shepherd Farm NPL Site
assuming that weather conditions do not cause extreme delays, this alternative could be
implemented in approximately 1 year.
The major engineering considerations in implementing the in-situ groundwater treatment system
include · ·
• pilot study for biotreatment process;
• siting and design of the mixing system and infiltration trenches;
• monitoring the effluent water quality from the mixing tank before discharging to
trenches;
• process effectiveness monitoring; and
• cleanup verification.
The major system components, construction equipment, and materials required for operations
under this alternative include
• contractor's temporary facilities and utilities;
• process unit for the in-situ groundwater treatment system (i.e, mixing tank and nutrients);
• water source for the mixing system; and
• system instrumentation and controls.
Long-term groundwater monitoring for cleanup verification purposes and to track contaminant
plume migration would be required under this alternative. Samples would be collected from
selected existing wells and analyzed for the site indicator parameters.
The in-situ groundwater treatment system also would require monitoring, with possible
maintenance of the mixing system, during its approximate 15-year operational life. Monitoring
of the. treatment system may include periodic sampling of the levels of microorganisms,
nutrients, and oxygen that are being added before infiltration into the aquifer.
Maintenance of the biotreatment system would be performed in accordance with operation and
maintenance requirements developed after equipment specification and procurement are
completed. At a minimum, it is expected that regular periodic maintenance would be required
on the mixing system to ensure its efficient operation.
Operation and maintenance of the in-situ treatment system would be conducted by a contractor
who would be responsible for continuous operation and maintenance of the process. Process
control would be automated as much as possible with the contractor stopping by periodically to
checkup on the system.
Cost
The total present worth cost for this alternative is approximately $4,578,440. The estimated·
annual operation and maintenance cost is approximately $309,285. Total capital costs are
estimated to be $1,378,000.
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Record of Decision September 1995 GE/Shepherd Farm NPL Site
selected existing wells and analyzed for the site indicator parameters.
The in-situ groundwater treatment system also would require monitoring, with possible maintenance of the mixing system, during its approximate 15-year operational life. Monitoring
. of. the treatment system may include periodic sampling of the levels of microorganisms,
nutrients, and oxygen that are being added before infiltration into the aquifer.
Maintenance of the biotreatment system would be performed in accordance with operation and
maintenance requirements developed after equipment specification and procuremer.t are
completed. At a minimum, it is expected that regular periodic maintenance would be required
on the mixing system to ensure its efficient operation.
Operation and maintenance of the in-situ treatment system would be conducted by a contractor who would be responsible for continuous operation and maintenance of the process. Process
control would be automated as much as possible with the contractor stopping by periodically to
checkup on the system.
Cost
The total present worth cost for this alternative is approximately $4,578,440. The estimated
annual operation and maintenance cost is approximately $309,285. Total capital costs are
estimated to be $1,378,000.
Alternative GW7b -Groundwater Treatment; Gradient Control; Off-Site Discharge
This alternative is identical to Alternative GW7a, except that the treated groundwater would be
discharged to the local POTW.
Overall Protection of Human Health and the Environment
This alternative would provide the same overall protection of human health and the environment
as Alternative GW7 A.
Compliance with ARARs
The in-situ bioremediation process would be designed to meet the remedial goals for the GE Site
and the process would be continued until the goals were attained.
Short-Term Effectiveness
As with alternative GW7a, the short term risks would be similar to those discussed for remedial
alternative GW6a. No adverse environmental impacts are anticipated.
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Record of Decision September 1995 GE/Shepherd Farm NPL Site F
Long-Tenn Effectiveness and Permanence.
This alternative would provide the same degree of long term effectiveness and permanence as
Alternative GW7A.
Reduction of Toxicity, Mobility, and Volume
This alternative would provide the same reduction of toxicity, mobility, and volume as
Alternative GW7a.
Implementability
An estimated nine months will be required for design and contractor selection. The actual
implementation of the alternative, including site preparation, construction of the infiltration
trenches, installation of extraction wells, installation of the mixing system, and installation of
the ex-situ treatment system, may take another six months. Therefore, assuming that weather
conditions do not cause extreme delays, this alternative could be implemented in approximately 1.5 years. ·
The major engineering considerations in implementing the gradient control system and the in-situ
and ex-situ groundwater treatment include ·
• ..
•
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•
•
• ..
•
citing, design, installation, and testing of extraction wells for gradient control;
potential for well plugging (reduction in flows) over time;
piping of extracted water to the mixing system and ex-situ treatment system;
monitoring the extracted water quality for possible treatment before use in mixing
system;
. pilot study for biotreatment process;
pilot study for_ ex-situ treatment processes;
citing and design of the mixing system, infiltration trenches, and ex-situ system;
process effectiveness monitoring; and
cleanup verification .
The major system components, construction equipment, and materials required for operations
under this alternative include
•
•
•
•
•
contractor's temporary facilities and utilities;
wells and submersible groundwater pumps;
pumping, piping, fittings, and valves for fluids transport;
process unit for the in-situ groundwater treatment system (i.~mixing tank and nutrients);
process unit for the ex-situ groundwater treatment system, if necessary; and
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Record of Decision September 1995 GE/Shepherd Farm NPL . Site
• system instrumentation and controls.
Cost
. The total present worth cost for this alternative is approximately $4,969,250. The estimated ·
annual operation and maintenance cost is approximately $345,285. Total capital costs are estimated to be $1,378,000. ·
Comparative Analysis of Alternatives
Presented in Table 24 is ranking scores for each non-cost evaluation criteria. Each alternative's
performance was ranked on a scale of zero to five, with zero indicating none of the criteria' s
requirements were met, and five indicating all of the requirements were met. The ranking
scores are not intended to be quantitative or additive. They are summary indicators only of each
alternatives performance against the non-cost evaluation criteria. The ranking scores combined
with the present worth costs provide the basis for comparison among alternatives.
Under overall protection, the no action alternative (Alternative 1) is ranked the lowest ("0")
since contaminated soil and groundwater are left on-site with no further actions being conducted.
Alternative 2 is ranked slightly higher (" l ") since deed restrictions and fencing would be implemented to limit contact with the contaminated soil and groundwater. Alternative SS5 is
ranked higher ("3 ") than Alternative 2 since contaminated soil at the GE Site would be capped,
thus reducing migration of contaminants via rainfall infiltration. The remaining alternatives (SS3
and SS4; GW6a through GW7b) are ranked the highest (''5") since contaminated soil and
groundwater are being either removed, treated, and/or disposed.
Under compliance with ARARs, Alternatives 1 and 2 are ranked the lowest ("0") since
contaminated soil and groundwater .remain on-site and chemical-specific ARARs are not met.
Alternative SS5 is only slightly lower than the removal and treatment alternatives; however,
ARARs are still met. AHernatives SS3 and SS4 are ranked high (''5") since contaminated soil
is being removed and either disposed off-site or treated on-site with backfill of treated material
on-site. Alternatives GW6a and GW6b and ranked slightly lower ("4") than Alternatives GW7a
and GW7b (''5") since pump-and treat may not be as effective as in-situ treatment in remediating
groundwater.
Under long-term effectiveness, the no action alternative (Alternative 1) is ranked the lowest ("O")
since contaminated soil and groundwater are left on-site with no further actions being conducted.
Alternative 2 is ranked slightly higher (" 1 ") since deed restrict\2ns and fencing would be
implemented to limit contact with the contaminated soil and groundwater. Alternative SS5 is
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Remedial Alternative Overall Protection of
Human Health and the
Environment
1 -No Action 0
2 -Institutional Actions I
SS3 -Excavation; Off-site Disposal 5
SS4-Ex-situ Treatment; On-site 5
Disposal
SSS -Containment 4
OW6a-Ex-situ Treatment; On-site 5
Discharge
OW6b -Ex-situ Treatment; Off-5
site Discharge
OW7a-Groundwater Treatment; 5
On-Site Discharge
OW7b -Oroundwatc Treatment; 5
Off-Sito Di barge
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Table 24
COMPARATIVE ANALYSIS OF ALTERNATIVES
GE/SHEPHERD FARM NPL SITE
Criteria Rating (a)
Compliance with Long.Term Reduction ofM/T/V
ARARs Effectiveness and Through Treatment
Permanence
0 0 0
I I 0
5 5 4
5 5 4
4 3 3
4 4 4
4 4 4
5 5 5
5 5 5
(a) A ranking of "0" indicates noncompliance while a ranking of "5" indicates complete compliance.
SW -SOIL WASHING
SIS -SOLIDIFICATION/STABILIZATION
BIO -BIOREMEDIATION
I!!!!! !!ml!
Short-Tenn Implementability Present Worth
Effectiveness
'
5 5 $160,211
4 4 $346,362
3 4 $1,524,235
3 3 SW -$4,174,375
SIS -$3,040,287
BIO -$1,955,437
3 3 $855,297
3 3 $5,328,398
,
3 3 $6,076,336
3 3 $4,578,440
3 3 $4,969,250
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09/.27/95 17: 19 EPA REGION JU WASTE MGT PROGRAMS 002
Rboord of Decision Soptemb"r 1995
Oll/Shcphonl Farm NPL Sit<>
ranked higher ("3") tl1an Alternative 2 since contaminated soil at the GE Site would be capped,
thuo reduc.ing migration of contaminants via-rainfall lnflltratlon. Alternatives GW6a and GW6b
and nmked slightly lower ("4") than Alternatives GW7a and GW7b ("5") since pump-and treat
may not be M effective as ln-~llu treatment in rcmcdiatlng groumlwater.
Under reduction of M/T/V, Alternatives l and. 2 are ranked the lowest ("O") since contaminated
soil and groundwater remain on-site. Alternative SSS is only slightly better in that an asphalt
cap would be placed at the GB Sl1e; thus, mobility is reduced. Alternative SS3 is ranked slightly
higher ("4") slnci, contaminated soil ts being removed and disposed off-site. Therefore, mobility
is eliminated; however, volume and toxicity remain the same. Alternative SS4 is ranked the
oamc as SS3 since ~oil is removed and treated on-site before being placed back on-site. Note
that the volume may increase, however, due to solidification. Alternatives GW6a and GW6b
and ranked sllghlly lower ("4") than Alternatives GW7n and GW7b (''5") since pump-and treat
may not be as effective \IS in-8itu treatment in' remedialing groundwater.
Under 8hon-term effectiveness and implementability, AlternatiVe l is ranked tile highest ("5")
since no further actio11s are being conducted. ,Alternative 2 is ranked next ("4") since tJ1e only
action laking place is monitoring, dee:d res!ricllons, and maintaining the perhneter fence. The
remaining alternatives are ranked al a "3 •.
XI. TIIE SELECTED REMEDY
.Based upon considi:ration of the requirements of CERCLA, tlte NCP, lite detailed analysis of
alternatives and public and state comments, EPA has selected both a source control and
groundwater remedy for this Site. At the cmiiplction of this remedy, the risk associated with
this Site has been calculated to be witliin tho., accepted risk range determined to bl' protective of
human hcalll1 and the 1:mvirornmmt. The tolal present won!J of die selecre<I rcme<ly for sons
($855,297), and Alternative GW7A for groundwater ($4,578,440), is estimated at $5,433,737.
See TublC11 25 1111d 26 for the detailed Co8t estimates of lh\lSe chosen alternatives.
Remediation will not be conducted at die Seldon Clark Subsite, Soll and groundwater were
below the remediation go11ls for the Sile.
A. SOURCE CONTROL
Source Control remediation will address t11e contaminated soils and materials at t11e Site. Tim
GE source control remedy requires that the soils contaminated above the remediation levels on
the GE Subsite be cove.red wilh !Ill impenncablc cap. The cap will be a composite liner and
shall consist of 18 Inches of clay, a flexible membrane liner, and if necessary, a drainage layer.
A stonn waler management system will be developed to route stonn water 11w11y from the cap
and to prevwt any negative impacrs from waier runoffs. The integrity of the cap will be
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15:42 EPA REGION JU ~STE MGT PROGRAMS 008
R&eord of Ps:oision
OB/Shophcrd Porw NPL Slto
September t 995
"
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...
Additional monitor wells shall I be placed and sampled at the Shepherd Fann
Subsite to detennlne l11e extent of the groundwater contamination.
Additional fish tissue samples will be collected in Bat Fork Creek and Mud Creek
to detennine the extent of PCB~contan1lnated fish.
Perlodlc sampling of the snlface water and sediments of Bat Fork Creek to
detennine if the gmundwater remediatlon is having a positive effect on the quality
of the creek.
Mo11itor well inslallalion to denionstmte that tbeie is no grnundwater
contamination caused by the dry sludge impoundment area and that the waste is
at least four feet above the seasonal high wntcr table,
Additional soil sampling to confirm the outline of the sludge impouodment
contamination.
Additional isampllng and testing to demonstrate that the PCB contaminants are
stabilized within the lrnpoundment sludges aml will not leach to the environment.
XII. DOCUMENTATION OF SIGNIFICANT CHANGE
CERCLA Section 117(b) requires an explanatiou of slguificant change from the preferred
alternative prosented in tho Proposed Plan. In the proposed plan, Alternative SSj was chosen
for GE soils and Alternative SS3 was chosen for the Shepherd Fann soils.
However, comments were received questioning the remedial a~tion on the dry sludge
impoundment area on the GB property. GB Bainpled the dry sludge impolllldment in 1991. The
results or this sampling investigation are given in Fiaure 28. Specifically, tbe dry sludge
impoundment is fenced and therefore, direct contact with the so:ils is prohibited. However,
fencing ls simllar to Alternative 2 -Institutional Controls. Tlte comparative analyses revealed
that Allemative 3 • Containment would be best suited for the GE Site. Therefore, to be
consistent, the decision was made to include the dry sludge lmpoundment as an area requirtng
an lrnpermeable cover.
Consequently, since the dry sludge impoundment has not been found to be a groundwater threat
or a surface water run-off threat, Alternative SS3 -Excavation and Off-Site Disposal for the
Shepherd Pann Site has been changed to inclmte disposal of tile excavated soils at th" GE sludge
impoundment instead of a RCRA Subtitle D Landfill. This change will result in the same risk
reduction at a lower cost.
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15:38 EPA REGION IV l.fiSTE MGT PROGRAMS 003
Record of Docision Seprember 1995
OB/Shophonl For';" NPL Site
and inspected on a regular basis for signs , of erosion, settlement, or subsidence. Deed
restrictions will be required to limit the use of the areas and to prevent subsurface development.
Additional sampling and characterization of t.andfill A must be completed to confinn t11e
effectiveness of a cap. The additional characterization will evaluate the possibility of the
presence of dense nonaqucous phase liquids (DNAPLs) and liquid waste in containers buried in
the landfill. If containerized wastes are ill the landfill, then these may requin: excavation and
tieatmeut or disposal at an approved facility. If there is no containerized waste, soil vapor
extraction or a vent in the cap may be warrnnted, depending on the concentrations of the VOCs
in the soil.
Performance Standards
Landfill A, LancJfill B, am.1 the clry sludge lmpounctment will be covered witll an lmpenneao1e
cap as specified above. These areas contain 8◊ils contaminated with greater tban 10 ppm total
PCBs, the perfonnance standard al the OE Subsire. Al tile Shepherd Fann Subsite, surficial
soils contaminated with PCBs above the perf(mnance standard of l ppm total l'CBs will be
excavated and transported to the dry sludge impoundmenl area of the GE Subsite. Surficial soils
. are defined as the rone from the smface to J 2 'inches below grade. The excavaled area will be
regraded and backfilled with clean soil. Jn addition, the areas will be revcgctatcd. Residential
yards will be restored as close ns possible lo t.hcit" o,·i1:,..Jnal 11ppeurance. Air quulity 111onitoring
shall be conducted at the perimeter of the excavation site to ensure that residents are not
adversely affected.
Short-term impacts to the Spring Haven community will be kept to a minimum by utilizing
Spring Haven drlve as little as possible. For health and safety considerations, tl,e residents
within the areas of contamination may, at EPA' s discretion, be temporarily relocated to avoid
injury and/or if utllltles are disconnected during the excavation period.
B. Groundwater Remediation
Groundwater remediation will address the contaminated groundwater at tl1e Site. Groundwater
remediation will include extraction of contaminated groundwater, treatment, in-situ
bioremediation and final discharge to Bat Fork Creek, or the treated water may b1: used as a
source of water in the in-situ treatment of the groundwater. The viability of using the treated
water in GE's plant process may also be evaluated.
The ex-situ u-eam1cnt wm consist of air stripping to remove organics, ancJ granulatcct activate(!
carbon adsorption to treat the vapor effluent, . or off-gas to remove the comamlnants stripped
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09/427/95 15:39 EPA REGION IU I.ASTE MGT PROGRl'f1S 004
Roooc4 9f D~cision
Oll/Shcphord Form NPL Site
SpPtomber 1995
from the groundwater prior to being discharged to the atmosphere. If metals are detected in the
liquid effluent at co11centralio11s above ll10 dilich~e limitations, a process option to remove
metals will be added to this treatment train. ln addition, the groundwater may need filtering
prior to treatment to remove· any particulates that may hann Ilic alr stripper. The in-situ
treatment will involve the construction of infiltration trenches or injection wells at an appropriate
location at both tho GE and Shephel'd Fann Subsites to introduce microorganisms, nutrients, etc
Into the aquifer. The ex-situ treatment system will be located on the OE facility, with
contaminated groundwater from Shepherd Farm pumped to this location.
The groundwater system will operate 24 hours per day. System controls will allow complete
nutom11tic operation with minimal opernlor attention. Long-tenn monitoring for cleanup
verification pmposes and lo track contamina11t plume migration will be required. The system
is expected to operate 15 years; swnples will be collected from 20 existing wells 011 a quarterly
basis for the first 5 years, and on an annual basis for the following 10 years. The groundwater
l.t-ealment system will also require monitoring: and maintenance. Monit011ng of the treatment
system will include periodic sampling of the influent and effluent from the treatment system and
analysis in accordance with the surface water ~ischa:q;e requirements.
B,1, Extraction and Pcrfonpance StamlHrds
Groundwater will be extracted from the GB fn¢ility and tho Shepherd Farm property. Location
and number of extraction wells and pumping rates will be dctennined during the remedial
design. Final discharge wlll be to Bat Fork Creek. Discharge standards will be driven by the
~urface water discharge requirements (ARARs1 See Section VII) and will be defined during the
development of the Remedial Design. ·
The goal of this remedial action Is to restore the groundwater to its beneficial use. Based on
infonnation obtained during the RI, and the ar\aly~is of all remedial alternatives, EPA and tl1e
State of North Carolina believe that the selected remedy will be able to achieve this goal.
Groundwater colltaminatlon may be especially persistent in the immediate vicinity of the
contmninants' source, where concentrations are relatively high. The ability to achieve
remediation lcv1,15 at all points throughout 'the area of attainment, or plume, cannot be
detennin~ until the extraction system has been.implemented, modified, as necessary, and plume
rospo1uc monitored over time.
Gmundwater shall be treated until the following performance stllndard" ,u-o attained throughout
tlie contaminant plumes:
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15:40 EPA REG I ON I U .iqsTE MGT PROGR~S 005
Roeord of Dech:jou
Gll/Shophonl Parm NPL Sito
Contaminant
Barium
Beryllium
Niokbl
L<>nd
MA»9°'°ci:~
Vinyl Chlorido
1,~-l>Johl~l"O->thcno
Tfi~htoroe,thone-
Bcnr.cno
Tet.ra.chloroetheuo
Nitrobonz.c:no
Chlorofonn
1,2-D!chloroelhnno
Remediation Uvel
2,000 us/l
4 ug/1
IOO ugll,
1 ~ ng/1 ,
SO ui;II
I u5/I
70 usll
2.8 u;ll
I ug/J
1 usll
10 ug/I .
l ug/1 ,
I ug/1
tazara Index V-UJ • .1.<eiates to non-cancer nsks
Risk Level
HI -l
lll-04
HI~ 1
NA
HI = 0.6
rn-o,
HI= 0.4
IB-06
!Il-06
J.B-06
HI = I
HI = O.J
IE--06
lB-06 Risk Level -Probability for carcinogenic effects
NA -Not applicable. Risk from lead h not calculated using m or risk level.
September 1995
If tho selected remedy cannot meet tho specified perfonnancc standards, at any or all of the
monitoring points during implemenration, the contingency measures and goals described in this
section may replace tl1e selected romedy nnd goals for these portions of tl1c plume. Such
contingency measures will, at ~ mini.mum, prevent further migration of the plume and include
a combination of co111ainmcnt technologies and Institutional controls. These measures nre
consluered to be protective of human health and the environment, and are technicalJy practicable
ullder the corresponding circumstances.
The Belected remedy will include groundwatel' extraction for an estimated period of lS year~,
during whi<;h timt> the systcm'5 pcrfonnance "'.ill be carefully monitored on a regular ba5is and
adjusted as warranted by the performance data collected duriug operation. Modifications may
include any or all of the following;
a) at individual wells where remediation levels have been attained, pumping mny be
discontinued;
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15:40 EPR REGION JU l,IClSTE MGT PROGRAMS 006
Fennrd of n~ition Soptcmbor 1995
Oil/Shophord Pnrm NPL Slt•
b)
c)
cl)
alternating pumping at wells to ,eliminate stagnation points;
pulse pumping to allow aquifor equilibration and . encourage adsotted
contaminants to partition into groundwater;
installation of addltlonal extraction wells to facilitate or accelerate cleanup of the
contaminant plume.
To ensure that cleanup continues to be maintained, the aquifer will be monitored at those wells
where pumping has ceased on an occurrence of al least every 2 years following dlscontlnuatlon
of groundwater extraction,
If it is determined, on the IY.tbis of the preceding .criteria and the system performance data, that
certain portlons of the aquifer cannot be restored to .their beneficial use, all of tile following
measures involving long-term management may occur, for an indefinite period of time, as a
modification of the existing system;
a)
b)
c)
engineering control5 such as pliysical barriers, or long•tenn grndk:m cuntrol
provided by low level pumping; as contaminant measure;
perfonnance st:llndards may be waived for the cleanup of those portions of (he
aquifer based on the teclutical impracticability of achieving further contaminant
reduction;
in$titutional controls may be prnvlded/malntaincd to restrlcl acu:ss to those
portions of the aquifer which remain above remediation levels;
d) continued monitoring of specified wells; and
e) periodic reevaluation of remeclllil teclmologles for groundwater restoration.
The decision to h,vokc any or all of these me.jsures may be made during a periodic review of .
the remedial act.ion, which will occur at 5 year lnteivals in accordance with CER.CLA Section
121 (c).
The remedial actions shall comply wilh all ARAR:; (See Section VII). The applicability of
RCRA Land Ban Requirements to the removal of the contaminated soil from the Shepherd Fann
Subslte to the GE Subsl!e was investigated and found not to be applicable. Similarly, the
TOSCA regulations were lnves1lgatlon to cletennlne their appltcablllty to capping Ille dry sludge
impooundment area; they were not found to be applicable.
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09/27/95 15:41 EPR REGION IV WASTE MGT PROGRl'i'IS 007
Recru:4 or De-ojoion
OB/Shophonl Parm NPL Sao
Soplombcr t99'5
The presence of contamination contained onsite and the presence of contaminants in the
groundwater will require d=! mcorcla!lon/ restriction to document their presence ancl could limit
future use of the property. The extent of the property restrictions and limitations will be
determined during the remedial design.
c. Additjonel Semplln~ Reqpjremcnts
Additional groundwater and soil sampling shiui be conducted to further define the extent of
contamination. Spccmcally, the followlng shall be obtained at a minimum:
..
Additional •oil slilllplcs shall be collected in Landfill A, If sampling results
indicate signifiyant voe contamination, fate and transpon analysis of voe
contamination may be warranted. In addition, an evaluation of the likelihood of
vapor transport around the cap: upward to the atmosphere and vapor transport
downward to the groundwater ']lay be needed,
Additional sol! samples shall be collected in the vicinity of monitor wells MW-14
and MW-25, These areas may Jmve undiscovered sources.
Additional monitor wells shall be placed and san1pled: 1) east of Bat Fork Cn:ck
between tempo111ry well TW-1 ;and TW-2; 2) west of Spananburg Hwy across
from MW-25 and MW-26; 'and 3) north of Tabor Road across from
Landsprcadlng Area A. The putpose of these wells is to further define the extent
of groundwater contami11atio11,
Periodic sampling of private wells in the area that are used for drinking water
puiposcs. As pan of the Remedial Design, aclclilional ~ampling of private wells
include wells located upgradient of the GB and Shepherd Fann Subsites. These
wells will be 6clcclcd to evaluate the effect of fracture-flow on the groundwater
contamination.
Sampling near monitor well MW-35 to ctetenuine if additional source areas are
present. Additional groundwater investigation near this well.
Additional soil samples shall be collected 011 a 25-foot grid throughout the
suspected area of soil contamination at the Shepherd Flliln property to detennlne
the aerial extent of surficlal PCB contamination and to determine the location of
any existing VOC sources. Additional soil samples shall also be collected north
and west of locations 53 and 56.
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GATE ODO
+00 • 2200
OEO+SO • 1500
OEO+l~~
OCO+lSO • . ,~o
000+15
oC\i
.... 0 OEO+l
x---
GENERAL. ELECTRIC
COMPANY
HENDERSONVILLE,
NORTH CAROL INA
.,_
OFO+SO • 1700
.d'b.
FD+
I!!: .a LAW ENVIRONMENTAL y . INC.
FIGURE28
LEGEND
OAO+SO • 1200
ND
HANO AUC[R BORING LOCATION
MAXIMUM PCB CONCENTRATION (MC/KC)
NOT DETECTED
50 ISOPLETH LINE nr PCB --CONCENTRATION ( HG/KC I
0 so
SCALE IN FEET
DRY POND -
PCB ISOPLETH MAP APPROXIMATE DEPTH 0-6"
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Record of Decision
GB/Shopbord !'arm NPL Site
17: 19 EPR REGION IU IJ'ISTE MGT PROGRAMS 003
Soptomber 1995
If the additional sampling and well installation outlined in Section XI.C shows that a cap will
not be effective In containing this contamination, lhen anolher ·remediation wchnology will be
selected to control this source.
In addition, In the proposed plan, it was staled lhal "Asphalt is considered the most appropimte
cappping material because portions of the landfills are already paved." Asphalt may be the top
layer, however the remedy has been supplemented to include in the cap 18 inches of clay, and
a flexible membrane. The cost estimate, however, has not been amended to include the cost of
these additional cap layers.
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