NCD981023260_19920512_Potters Septic Tank Service Pits_FRBCERCLA SPD_Public Meetings 1991 - 1992-OCR

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POTTER'S SEPTIC TANK SERVICE PITS
SUPERFUND SITE
Sandy Creek, Brunswick County, North Carolina
PROPOSED PLAN MEETING
AGENDA
May 12, 1992
7:00P.M.
Hood Creek Community Center
Highway87
Sandy Creek, North Carolina
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AGENDA
Welcome & Introduction of Participants
Glenn Adams, Risk Assessor
Diane Barrett, Community Relations Coor.
Darcy Duin, Remedial Project Manager
Curt Fehn, Chief, N.C. Superfund Section
Meeting Purpose, Review of Community
Relations Activities & Overview of
Superfund Process
Site Description, History, Results of
Remedial Investigation & Feasibility Study
Remedial Alternatives and EPA 's Preferred
Alternative
Question and Answer Session
Closing Remarks, Adjournment
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ADMINISTRATIVE RECORD
Columb"D:5 County Library
East Columbus Branch
P.O. Box 27, Highway 87
Reigelwood, North Carolina 28456
. (919) 655 -4157
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AREAS EllCAV.uED (XJRINO REM'OIAL ACTION
MARCIi 1984
11.9. ENVIIIONMlcNTAI
IN'l'ERREI--A'l'IONSIIIP BETWEEN RI,MEDIAL INVES'l'IGA'l'lON ANO Ff!ASIIITT, l'J'Y S'l'IIDY AC'I' IV I 'I' I ES
HEMEOIAL INVESTIGATION •
RISK ASSESSMENT
DATA DATA
COLLECTION EVALUATION
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FEASIBILI'l'Y S'l'UOY
EXPOSURE TOXICITY
ASSESSMENT ASSESSMENT
REMEDIAL AREAS/ GENEl!AT. TN 1 'l'IAL/ FIN~-
ACTION VOLUMES HESPONSE 'l'ECIINICAL DETAILED
OBJEC'l'IVES ACTIONS SCREENING EVALUATION
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SOIL CLEANUP STANDARDS
Contaminants Concentration Cleanup
Range Standards
· Benzene .012 - 7 ppm .010 ppm
Toluene .003 -81 ppm 3.4 ppm
Ethylbenzene .001 -84 ppm .235 ppm
Xylenes .001 -580 ppm 3.5 ppm
Napthalene .41 -50 ppm 1.8 ppm
Lead 1.1 -76 ppm 25 ppm
Chramium 1.8-170 ppm 97.2 ppm ~,--
Zinc* 1.2 -3300 ppm 122 ppm
*Note: Zinc cleanup standard applies only to the top foot
of soil.
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VOLUME OF SOIL WlHCH WH,L BE
EXCAVATED AND TREATED:
10,100 CUBIC YARDS
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SOH., REMEDfATION ALTERNATIVES
1. NoAction
Cost: $140,000
2. Institutional Controls
Cost: $1.4 Million
3. Excavation and Off-Site Disposal
Cost: $8.1 Million
4. Stabilization/Solidification
. Cost: $5.5 Million
5. On-Site Incineration
Cost: $12.4 Million
6. Soil Washing and Off-Site Incineration
Costf $12.3 Million
7., Low Temperature Thermal Desorption and
Stabilization
Cost: $4. 7 Million
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GROUNDWATER Cl.EANUP STANDARDS
Contaminants Concentration Cleanup
Range Standards
Benzene 90-3150 ppb 5 ppb
Toluene 29000 ppb 1,000 ppb
Ethylbenzene 22-2400 ppb 29 ppb
Xylenes 98 -. 26000 ppb 400 ppb
Napthalene 42-125 ppb 30 ppb
Lead 6-25 ppb 15i ppb
Chromium -19 -2500 ppb 50 ppb
• •
GROUNDWATER ALTERNATI1VES
1. NoAction
Cost: $140,000
2. Institutional Controls
Cost: $1.4 Million
3. Recovery and Treatment System
Chemical Treatment and Air Strippii.ng
(13 years}
Cost: $5.3 Million
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EPA'S PREFERRED ALTERNATIVE
FOR ADDRESSING CONTAMINATED GROUNDWATER:
Alternative 3 -Recovery and Treatment Syste1n
* Contaminated groundwater will be extractedfrom
within and at the periphery of the plunte via
extraction wells
* Extracted groundwater will be treated ,onsite in an
above-ground treatment process
* the treatment process will involve two steps: chemical
treament to treat the heavy metals and air stripping
to treat the voes.
* Chemical treatment involves a precipitation/
.flocculation/ filtration process which will remove the
heavy metals of concern: lead and chromium.
* The filtered material or sludge will be collected and hauled o.[f-sitefor treatment (if required) 1cznd disposal
in accordance with applicable regulations.
* In the air stripping system, the groundu,ater is
pumped to the top of an air stripping to1ver. While
the water cascades down through a large tube, a high-poweredfan literally blows the contaminants.from the
w~. The fan then sends the air out the top of the
air stripping tower. The contaminants will be treated by an off-gas system before the gas is released into
the atmosphere. This process will remove the voes.
* The treated groundwater will be discharged into
Chinnis Branch which will have to meet NPDES
requirements.
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Air Stripping Tower
Contaminated
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1. Contaminated ground water is withdrawn from the aquifer.
2. Contaminated water is distributed uniformly over loosely packed
plastic modules.
3. Water cascades down through the plastic modules. The droplets
are exposed to air forced upward through the tower. This process
strips the voes from the water.
4a. The treated water is then discharged into the river in compliance
with the requirements of waste-water permits.
4b. · Air mixed with a small percentage of VOCs is released into the
atmosphere. The low level emissions are not considered hazardous
to human health or the environment.
• •
EPA'S PREFERRED ALTERNATIVE
FOR ADDRESSING CONTAMINATED SOIL:
Alternative 7 -Low Temperature Thennal Desorption and Stabilization
* Excavate and treat soils contaminated above
cleanup levels, estimated volume -10,100 Cubic
yards
* The Low temperature Thennal DesorJJtion
treatment consist of volatilizing the organic
contaminants at temperatures usually between
300 -1000 degrees. This process will destroy the organic contaminants only.
* The treated soil will be tested. ifheav11 metals are detected (Zinc, Lead, Chromium), then that batch
of soil will be stabilized. if the soil does not contain heavy metals then it will be placed back from where it was ·excavated following applicable land disposal restrictions.
* Stabilization is a process where the soil will be mixed with an admix to convert the contaminants into their least soluble, mobile, or toxicfonn thus minimizing the potentialfor migration. This
stabilized mass will be placed back on-site or taken o.ff-sitefor disposal.
* The a.ff-gases from the thermal. unit will be treated. t-•
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EPA'S PREFERRED ALTERNATIVE
Groundwater (Alternative 3):
Recovery and Treatment (13 years}
Cost: $5.3 Million
Soil (Alternative 7):
Low Temperature Thermal Deso']1tion and
Stabilization
Cost: $4.3 Million
TOTAL c:i)sT OF REMEDY: $10.0 M11,1,l0N ·~~-··
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• •
UNITED S'l'ATES E!<Vl!'.C-N!~ENTA!, FR')":'£,;TlON AGENCY, REGION I'/
345 Coui~tlan~ Street, N.E.
Atlanta, GA 30365
FAXSIMILE 'fRANSMiss:f_2N SHEET
TO: PHONE, ----------------
FAX N\.MBER: -------------
IC the follo~ing messag~ is received poorly, Please cDll ----------
in our office at FTS 257-3004 or commerci~l [phone]
SPECIAL INSTRUCTIONS: ________ _
------------·--·-···--·--···-----·-..•
PLEASE NUMBER ALL PAGES
OFFICE C!f. FUBLIC AFFAIRS FAX NUMBER
~U\CHINE TYPE TELEPHONE NUMBERS
3M, ll5/ll5AD FTS 257-3721
COMM. [phone].
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EPA ·ro HOLD PUBLIC HEE'l'ING ON 1".AY. 12 IN SA~lDY CREEK, NOR'rH CAROl:.lNA
HEGARDING 'l'HE l!O'I"l'ERS SEPTIC 'l'ANK SERVJCES PITS SUPERFUND SITE
The U.S. Environmental Protection
Agency (EPA) will hold a public meeting on Tuesday, May 12, 1992,
regarding the Remedial Investigatlon/E'easi.bility Study findings that
determined the extent of c,1ntrunination and possible cleanup
alternatives for the Potters Septic Tank services Pits Superfund site
in Sandy Creek, North Carolina,
The meeting will begin at 7:00 p.m. at the Hood Creek Community
center on J-U.ghway 87 i.n Sandy Creek. Off.icials from EPA will discuss
results of the investigation of thr, site, the various alternative
methods of cleaning up or treating the cont11mination, the Agency's
p;r:eferred alternative, an overview of the Superfund program and
opportunities for community involvement i.n EPA' s selection of a
cleanup method. 1\. 30-day publJ.o co,nme11t period •Jn the study began on
April 3::l and will end on 11ay 30, J\.ll interested individuals are
invited to attend the meeting and pr<)vide conmient:.s.
The site is located in a rural section of Brunswick County off
Highway 74/76 west c,f Wilmington. Between 1969 and 1976, the land
was used as a disposal area_ Contarninants co11Bist of waste petroleum
products and septic tank sludge"'. w)1tch were placed in shallow,
unlined pits or spread directly on the land. The site was placed on
EPA's Natlonal Priorities List of hazardous waste sites in March
1989.
Documents concerninCJ the si t<":t are 1wailable for public review
the Columbus County Library, East C:olumtms Branch, Highway 87,
Reigel.wood, North Carolina.
-0-May 6, 1992
CONTACT; Diane Barrett, Conm~,un:Lty He,lations, 40•1-347-7791
Charlis Thompson, Press Office, 404-347-3004
/l. t
• • UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION IV
345 COURTLAND STREET. N.E.
ATLANTA. GEORGIA 30365 t<t.GEI Vt.U
4WD-NSRB hi~( 4 1992
April 21, 1992 SUPERRIND SECrfON
Charlotte Jesneck
NCDEHNR
Superfund .Section
401 Oberlin Road
Raleigh, North Carolina 27605
RE: Proposed Plan ract-5'/,e'-'f-'
Potter's Septic Tank Service Pits Superfund Site
Sandy Creek, North Carolina
Dear Ms. Jesneck:
Enclosed you will find the Proposed Plan for the Potter's Septic Tank
Service Pits Superfund Site in Sandy Creek, North Carolina. As I
have discussed with you, the public meeting will be held on May 12 in
Sandy Creek. Please notify me if you plan to attend this meeting. I
would also appreciate your review of this Proposed Plan as soon as
possible so that we can discuss any concerns you may have related to
the Preferred Alternative.
If you have any questions, please call me at 404/347-7791.
p~
Darcy Duin .
Remedial Project Manager
Enclosure
cc: Curt Fehn, EPA I
Printed on Recycled Paper
.UPERFUND PROPOSW PLAN FACT SHEET
POTTER'S SEPTIC TANK SERVICE PITS
Sandy Creek, Brunswick County,
North Carolina
INTRODUCTION
This fact sheet is one in a series designed to inform
residents and local officials of the ongoing cleanup
efforts at the Potters Septic Tank Service Ptts Su-
perfund Site (referred to in this document as Potter's
Ptts). Terms appearing in bi11rJ print are defined in
a glossary at the end of this publication.
This Propcsed Plan fact sheet has been prepared by
the U.S. Environmental Protection Agency -Region
IV (EPA) to propcse a clean-up plan, referred to as
a preferred alternative, to address contamination at
the Potter's Pits Superfund Stte (the Stte) located in
a rural section of Brunswick County, N.C. in a
residential comrruntty known as the Town of Sandy
Creek. As the lead Agency for oversight of remedial
activtties at the stte, EPA has worl<ed in conjunction
wtth the North Carolina Department of Environment,
Health and Natural Resources (NCDEHNR). In ac-
cordance wtth Section 117(a) of the Comprehen-
·Slve Environmental Response, Compensation,
and Llablllty Act (CERCLA), as amended by Su-
pertund Amendments and Reauthorization Act
SARA 1986, EPA is publishing this Propcsed Plan
to provide an oppcrtuni1y for public review and com-
ment on all the clean-up options, known as remedial
alternatives, under consideration for the Site.
The purpose of this Proposed Plan is to:
1) Surmiarlze the results of the Remedial In-
vestigation (RI);
April 30, 1992
2) Describe the remedial alternatives con-
sidered in the Feastbltlty Study (FS) Repcrt;
3) ldenttty the preferred alternative for the
remedial action at the Stte and explain the
reasons for the preference;
4) Solictt public review of and comment on all
the remedial alternatives described during a
30-day public comment period; and
5) Provide information on how the public can
be involved in the remedy selection process.
PUBLIC MEETING FOR
POTTER'S PITS SITE
The EPA will hoid a public meeting to discuss EPA's
~ropcsed Plan for clean up at the Potter's Pits
Superfund Stte. The meeting will begin at 7:00 on
May 12 and will be held at the Hood Creek Com-
munity Center. Representatives from EPA will
present EPA's preferred alternative and the other
alternatives considered in the FS Repcrt. After the
presentation, these officials will be available to
answer any questions or concerns the public may
have regarding the preferred alternative, other alter-
natives considered in the FS Repcrt or other con-
cerns related to the clean up of this Stte. Please plan
to attend.
PUBLIC MEETING NOTICE
DATE: May 12, 1992
TIME: 7:00 pm -9:00 pm
WHERE: Hook Creek Community Center
Highway 87
Sandy Creek, North Carolina
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FIGURE l
FIGURE z
The Potter's Ptts Sle Is located in a rural section of
Brunswick County, North Carolina in a residential
comrnmity known as the Town of Sandy Creek
(Figure 1 ). Sandy Creek is subdivided into one to
two acre lots, each wtth a private domestic water
well. There are approximately 150 residential lots of which 70 are currently occupied.
Between 1969 and 1976, before the land was
developed for residential use, the Skipper family
operated sludge hauling and oil spill cleanup com-
panies in this area. Waste disposal pits were
operated in and around the Sandy Creek area. Dis-
posal practices consisted of placing waste
petroleum products and septic tank sludges in shal-
low unlined pits or directly on the land surface.
The Potter's Pits Site was divided into three study
areas: Area 1 and 3 are located in residential lots
within Sandy Creek, and Area 2 was located ap-
proximately 1.5 miles north across U.S. Highway
74!76 (Figure 2). Area 1 comprises the actual
Potter's Pits Site. Area 3 was included in the inves-
tigation because historical aerial photographs sug-
gested that this area might. have beeil used as a
disposal site. Area 2 was not well de/ined and was removed from further investigation after an exten-
sive search indicated that no additional information
regarding its location or existence could be found.
In May 1976, the North Carolina Department of
Natural and Economic Resources (NCDNER) in-
formed Mr. Ward Skipper that an oil disposal pit
(Area 2) located near Maco violated North Carolina
statutes and must be cleaned up immediately. At
that time, approximately 2-3,000 gallons of black oil
was pu~ed from the pit and the pit area was
covered with soil. Documentation pertaining to the
chemical COIT'4)0sition of materials disposed in the
pit, the.fate of the liquid removed from the pit, and
the quantities and characteristics of the material
buried o~ site have not been found.
In August 1976, an unlined pit in Area 1 failed and
allowed approximately 20,000 gallons of oil to es-cape. The oil flowed into Chinnis Branch and then
into Rattlesnake Branch. The U.S. Coast Guard
responded pursuant to Section 311 of the Clean
Water Act to conduct the cleanup.
Also, in August of 1976, Mr. Otto Skipper (brother of
Ward Skipper) began pumping out the oil remaining
• in the breached disposal pit (Area 1 ). Approximately
20,000 gallons of oil were removed from this pit and
transported to Fort Bragg Military Reservation in
Fayetteville, North Carolina. Three other pits con-
taining oil, as well as the oil recovered from the
receiving stream, was also taken to Fort Bragg. In
addition, approximately 150 dump truck loads of oil
sludge and oil stained dirt were excavated and
hauled to Brunswick County Landfill in Leland, North
Carolina, for final disposal. The thick oil sludge that could not be pumped was mixed with sand and
buried on site.
The Skipper Estate changed ownership in 1980.
Wachovia State Bank, through foreclosure, took
possession of the property in January 1980. Invest-
ment Management Corporation later purchased the property and subdivided it for residential develop-
ment. This development became known as Sandy
Creek Acres and later as the Town of Sandy Creek.
Earl and Dixie Gurkin purchased the Site lots in
1982. They found waste materials buried in their
yard (Area 1) in July 1983. The State of North Carolina sampled the soil and groundwater.
Analysis of these sa~les confirmed the presence
of contamination. The Site owner's water well was
condemned, and they were connected to a
neighbor's well.
In September 1983, EPA and the Region IV Field
Investigation Team (FIT) performed an electromag-
netic survey of the Site, monitored the air under the
present owner's home, and collected soil, surface
water, and groundwater samples for laboratory
analysis. In February 1984, EPA-Region IV used
ground penetrating radar (GPR) to further define
the Site boundaries.
In March 1984, an Immediate Removal Action at the
Potter's Pits Site (Area 1) was requested by the EPA
Office of Emergency and Remedial Response. On March 21, 1984, a Superfund removal was begun
centering around Area 1. A total of 1,770 tons of oily sludge and contaminated soils were excavated and
transported to a hazardous waste landfill in Pinewood, S.C. Soil.removal activities· were com-
pleted on April 2, 1984. An emergency removal is
conducted at anytime at a site when there is an
imminent threat to human health or the environment
from a contaminant.
In May 1984, EPA-Region IV proposed a
groundwater monitoring plan to determine ~ the
Potter's Pits Site (Area 1) presented a threat to
-3-
• surrounding groundwater sources. Contamination
of the shallow aquWer had been documented at the
Stte (during the September 1983 FIT investigation)
in groundwater ~s taken from both a residen-·
tial and a monttoring well on Stte. However, in order
to characterize the nature and extent of the
groundwater contamination in this area, addttional
wells were proposed. Nine monitoring wells were
subsequently installed and sampled by EPA. The
locations of these wells were based on the assump-
tion that the groundwater flow was in a northeasterly
direction. The samples were analyzed for volatile
organic compounds. Relatively high concentra-
tions of benzene, ethylbenzene, toluene, and
xylenes (BETX) were detected in some of the
groundwater samples.
The wells were resampled in 1988 by the State of
North Carolina. These samples were analyzed for
volatile organics, phenols, priortty pollutant metals,
and several nutrients. BETX and phenols were the
predominant contaminants detected. In addttion,
the 1988 data indicated the possibiltty of low level
benzene, ethylbenzene, and xylenes in a "deep"well
which would indicate that the "deep" aquifer had
now been attected.
The Potter's Septic Tank Service Pits Stte scored
29. 14 out of a total of 1 oo on the Hazard Ranking
System (HRS). Any stte wtth a HRS score greater
than 28.5 is proposed for the National Priority List
(NPL). Potter's Ptts was proposed for addttion to the
NPL in June 1988. The Site was placed on the NPL
in March 1989 making it eligible for federal money
for cleanup under Superfund.
Based on these activtties, EPA determined that the
level and extent of on-site chemical contamination
warranted a more thorough assessment. Conse-
quently a Remedial Investigation (RI) was con-
ducted from January 1990 through April 1990. Alter
Phase I of the RI was completed, tt was determined
that a Phase II or RI Addendum would be necessary
due to lack of ~e information. Therefore, in
Aprilof 1991, EPA conducted the supplemental field
investigation to address the data gaps and ir-
regulartties identttied in the inttial RI. A report was
· generated in July 1991 which described the field
ettort.
OBJECTIVES OF THE REMEDIAL
INVESTIGATION
• As presented in our March 1991 fact sheet the
primary objectives of both phases of the Potter's Pits
RI were to assess the nature and distribution of
contaminants at the Stte and to characterize the Stte
hydrology and geology. The types of analyses in-
cluded in the RI were selected to characterize these
factors to the extent required to evaluate potential
risks, tt any, to human health and the environment,
and to evaluate alternatives for Stte remediation.
Toward this end, the RI analyzed for potential sour-
ces of contamination in the following media:
• Soils
• Air
• Groundwater
• Surlace water/stream sediment
CONCLUSIONS OF THE
REMEDIAL INVESTIGATION
PHASE I
The extent of contamination at the Potter's Ptts Site
is limited to the immediate vicinity of the two former
waste disposal areas (i.e., north and south of Joe
Baldwin Drive) and the areas immediately
downgradlentof each toward Chinnis Branch. The
dominant constituents detected during the RI include
compounds associated with petroleum products or
waste and metals.
The following conclusions were made regarding the
extent of contamination at the Potter's Pits Site
through Phase I.
• Area 3 is not an area of concern (See site map).
• The extent of soil contamination is limited to the
immediate vicinity of the two former waste pits
and seems to be restricted to the upper 15 feet
of soil. Petroleum constituents (BETX and
naphthalene) and lead and zinc were prevalent
throughout Area 1.
• Residential air within the house overlying one of
the former waste pits was not impacted.
• No residential well currently being used is being
impacted by contamination from the Potter's Pits
. Site.
• The extent of groundwater contamination in the
surficial aqutter is restricted to the area enccm-
passing the former disposal pits and an area
extending toward Chinnis Branch. Concentra-
-4-
• lions of contaminants decrease dramatically
toward Chinnis Branch.
· • Samples of both surface water and sediment
wtthin Chinnis Branch did not detect any con-
taminants above MCLs that could be attributed
to the Site.
PHASE II
After the completion of Phase I, several data gaps
were identttied resulting in uncertainties concerning
the lateral and vertical extent of contamination and
the hydrogeology of the Stte. In order to appropriate-
ly develop remedial alternatives, for the Stte, tt was
necessary to address these uncertainties. There-
fore, Phase II of the RI was done by EPA, Region IV.
The results of this phase are listed below:
•
•
•
•
The Phase II Remedial Investigation confirmed
the fact that the highest levels of contamination
are present in soils which roughly correspond to
the areas idenMied as the suspected ptt areas.
The Phase II data indicates that contamination
of groundwater has primarily been confined to
the shallow aqutter.
The Phase II data indicates that benzene may
be present in the deep aqutter at levels in excess
of current MCLs.
Phase II data confirms original RI data to the
extent that pesticides, PCB's, and cyanides do
not appear to be primary contaminants of con-
cern in etther suriace soils, subsurface soils, or
groundwater.
Phase II RI soils data revealed only one addi-
. tional contaminant, principally naphthalene, in
those areas for which soil remediation has been
targeted. Therefore, the overall volumes of soils
to be considered for remediation do not change.
• In general, organic constttuents observed in the
Phase II RI were very similar to those found in
the original RI. Concentrations of organics have
generally decreased in wells sampled during
both events.
• Groundwater data indicated that the levels of
contaminants, principally organics, are currently
in excess of established Maximum Con~
tamlnant Levels (MCL 's).
Addttional information about the RI findings and
supporting documents are available at the informa-
tion reposttory.
• SUMMARY OF SITE RISKS
Results of the BaseHne Risk Assessment
During the RI, an analysis was conducted to es-
timate the human health or environmental problems
that could result if the contamination identified at the
Stte was not cleaned up. This analysis, known as a
Basellne Risk Assessmen~ focused on the poten-
tial health effects from long-term direct exposure to
the contaminants found at the Stte.
The contaminants classttied by EPA as carcinogens:
benzene and carcinogenic PAHs were identttied as
the primary soil contaminants. The contaminant
specttic clean-up levels for each of the Site environ-
mental media are presented in the FS Report. Fu-
ture risk scenarios, based on reasonable maximum
exposures, were developed which estimated the
probahiltty of carcinogenic health effects that would
result from direct exposure to contaminants found in
soils. These scenarios were developed for both
adults working and children playing at the Stte. EPA
prefers that remediation of Superfund sttes achieve
a residual cancer risk no greater that 1 o·6 (1 chance
in 1,000,000). However, depending upon stte fac-
tors, a risk of 10·4 (1 in 10,000) may be considered
protective. The caiculated'upperbound risks from
exposure to all areas of the Stte would fall inside the
protective risk r?nge. The carcinogenic risk ranged
from 1 .96 x 10· to 3.18 x 10·6.
The non-carcinogenic toxicity risk from soil con-
taminants was also evaluated. This was done
through the calculation of a Hazard Index (HI). The
HI compares an assumed exposure level wtth a
reference level established by the Agency. The
reference level is the level where no health effects
occur. HI values above 1.0 indicate an unaccep-
table risk that increases in magnttude wtth higher
numerical scores above 1.0. The HI for dermal
contact for various areas of the Stte was 64.5 for lead
and 18.61 for zinc.
The human health risk posed by the ingestion of
groundwater was determined by comparing
detected levels of the contaminants with
groundwater standards for these substances. The
following chemicals were detected in concentrations
that exceed their respective standards: benzene,
toluene, ethylbenzene, xylenes, naphlhalene, lead
and chromium.
-5-
TABLE l • • SOIL CLEANUP STANDARDS
Contaminants Concentration Range Cleanup Standards
1. Benzene .012 -7 ppm . 010 ppm
2. Toluene .003 -81 ppm 3.4 ppm
3. Ethylbenzene .001 -84 ppm .235 ppm
4. Xylenes .001 -580 ppm 3.5 ppm
s. Naphthalene .41 -so ppm 1.8 ppm
6. Lead 1.1 -76 ppm 25 ppm
7. Chromium 1.8 -170 ppm 97.2 ppm
8. Zinc* 1.2 -3300 ppm 122 ppm
*Note: Zinc cleanup standard applies only to the top foot of soil.
TABLE 2
CLEANUP STANDARDS FOR GROUNDWATER
Contaminant Concentration Range Cleanup Standards
1. Benzene 90 -3150 ppb 5 ppb
2. Toluene 29000 ppb 1,000 ppb
3. Ethylbenzene 22 -2400 ppb 29 ppb
4. Xylenes 98 -26000 ppb 400 ppb
5. Naphthalene 42 -125 ppb 30 ppb
6. Chromium 19 -2500 ppb 50 ppb
7. Lead 6 -25 ppb 15 ppb
• SCOPE AND ROLE OF THIS
PROPOSED ACTION
Remedial response objectives were developed
based on the resuMs of the Risk Assessment and
examination of potential Applicable or Relevant
and Appropriate Requirements (ARARs). Action-,
location-, and chemical -specnic ARARs were ex-
amined. Chemical-specific ARARs for groundwater
include MCLs and North Carolina Groundwater
Standards.
Because there are no federal or state cleanup stand-
ards for contamination in soil, cleanup standards are
established to reduce soil contamination to within an
acceptable risk range. Cleanup standards at the
Potter's Pits Site will be established at stringent
health based levels. Cleanup standards were also
established to prevent any further degradation of the
groundwater. All state and federal ARARs will be
met. The contaminant specnic cleanup levels for
each of the Site's environmental media are
presented in Tables 1 & 2.
THE DEVELOPMENT OF EPA'S
PREFERRED ALTERNATIVE:
EPA's selection of the preferred cleanup alternative
for this Site, as described in this Proposed Plan, is
the result of a comprehensive evaluation and
screening process. The FS for the Site was con-
ducted to identny and analyze the alternatives con-
sidered for addressing contamination at the Site.
The FS describes the remedial alternatives con-
sidered, as well as the process and criteria EPA used
to narrow the list of potential Remedial Alternatives.
(Refer to the FS for details on the screening
methodology.)
EPA uses a s1andard set of nine criteria to evaluate
the alternatives identified in the FS. Although overall
protection of public health and the environment is the
primary objective of the remedial action, the
remedial alternatlve(s) selected for the Site must
achieve the best balance among these evaluation
criteria considering the scope and relative degree of
contamination present. The criteria are grouped into
three categories:
"Threshold Criteria": These two statutory require-
ments must be met by the alternative and are
described as follows:
• 1. Oyerau Protection of Human Heatth and the
Enylronment addresses how an alternative as a
whole will protect human health and the environ-
ment. This includes an assessment of how the
public health and environment risks are properly
eliminated, reduced, or controlled through treat-
ment, engineering controls, or controls placed on the
property to restrict access and (future) development.
Deed restrictions are examples of controls to restrict
development.
2. Compliance with Applicable or Relevant and
Appropriate Requirements (ABARs) addresses
whether or not a remedy complies with all state and
federal environmental and public health laws and
requirements that apply or are relevant and ap-
propriate to the conditions and cleanup options at a
specnic site. If an ARAR cannot be met, the analysis
of the alternative must provide the grounds for invok-
ing a statutory waiver.
"Primary Balancing Criteria": These are 5 con-
siderations used to develop a decision as to which
alternative would be best to use.
3. Long-term Effectiveness and Permanence
refers to the abilriy. of an alternative to maintain
reliable protection of human health and the environ-
ment over time once the cleanup goals have been
met.
4. Reduction of Toxicity. Moblllty. or Volume are
the three principal measures of the overall pertor-
mance of an alternative. The 1986 amendments to
the Supertund statute emphasize that, whenever
possible, EPA should select a remedy that uses a
treatment process to permanently reduce the level
of toxicity of contaminants at the site; the spread of
contaminants away from the source of contamina-
tion; and the volume, or amount, of contamination at
the site.
5. Shon-term Effectiveness refers to the likelihood
of adverse impacts on human health and the en-
vironment that may be posed during the construction
and implementation of an alternative until the
cleanup goals are achieved.
6. lmplementabmty refers to the technical and ad-
ministrative feasibillty of an alternative, including the
availability of materials and services needed to im-
plement the alternative.
-7-
• 7. CQJl1 includes the capital (up-front) cost of im-
plementing an alternative, as well as the ccst of
operating and maintaining the alternative over the
long term, and the net present worth of both caprtal
and operation and maintenance costs.
"Modifying Criteria": These two ccnsiderations are
used to determine the acceptability of the alterna-
tives to the public and local officials.
8. State Acceptance addresses whether, based on
its review of the RI/FS and Propcsed Plan, the State
concurs with, oppcses, or has no comments on the
alternative EPA is propcsing as the remedy for the
Site.
9. Community Acceptance addresses whether the
public concurs with EPA's Propcsed Plan. Com-
munity acceptance of this Propcsed Plan will be
evaluated based on ccmments received at the up-
coming public meetings and during the public com-
ment period.
SUMMARY OF ALTERNATIVES
The following section provides a summary of the
alternatives which were developed io address the
soils and groundwater contamination at the Potter's
Pits Site. The primary objective of the FS was to
determine _and evaluate alternatives for the ap-
propriate extent of remedial action to prevent or
mitigate the migration or the release or threatened
. release of hazardous substances from the Site.
The following descriptions of remedial alternatives
are summarizations. The FS Repcrt contains a
more detailed evaluation of each alternative and is
available for review in the information repcsitory.
REMEDIAL ALTERNATIVES TO
ADDRESS GROUNDWATER
CONTAMINATION
Three sets of alternatives were developed to ad-
dress groundwater ccntamination at the site. The
groundwater central (GWC) alternatives are listed
and described below.
GWC-1: No Action
CERCLA requires that the "No Action" alterna-
tive be considered to serve as a basis against
which other alternatives can be ccmpared. The
current residents would remain on-site, and no
• institutional restrictions would be implemented.
A review of remedy would be ccnducted every
five years.
Costs: The total present worth: $140,000.
GWC-2: Institutional Controls
The Institutional Controls alternative includes the
following:
-The residence on the property would be
mcved lo another location.
-Water well construction permit restrictions for
areas within the zone of influence (ZOI) of the
ccntaminated plume.
-A monitoring program which would monitor
groundwater for 30 years.
Costs: The total present worth: $1,400,000.
GWC-3: Groundwater Recovery and Treatment
This alternative involves the reccvery of all Site
groundwater currently exceeding clean-up
standards through a system of numerous ex-
traction wells. The treatment system for the
extracted groundwater would involve installing
piping from each extraction well to a common
treatment area, a specttic treatment system.
and discharging the treated groundwater into
Chinnis Branch. This treated groundwater
would meet the substantial requirements of a
National Pollutant Discharge Elimination Sys-
tem (NPDES) permit and any other ARARs.
Because of the nature of contaminants, it is
necessary to use a "treatment train" system
where several different technclogies are used
to treat the different contaminants. For
groundwater, air stripping would be used to
remove the voes and a combined chemical
treatment would be used to remove the heavy
metals from the groundwater which includes
precipitation/flocculation/filtration. These tech-
nologies are described below:
-8-
AIR STRIPPING
In the air stripping system, the groundwater is
pumped from the well and sent to the top of an
air stripping tower. While the water cascades
down through a large tube, a high-pcwered fan
literally blows the contaminants from the water.
The fan then sends the contaminanted air out of
the top of the air stripping tower. The volatilized
• contaminants are treated by an off-gas system.
The air stripping system is most effective in
removing VOCs; tt is not as effective with other
contaminants, such as heavy metals.
CHEMICAL TREATMENT
The chemical treatment process used in this
alternative involves precipitation/floccula-
tion/filtration for the remcval of the heavy metals
of concern (lead, zinc, chromium). Precipitation
involves addition of chemicals to the
groundwater to transform dissolved con-
taminants into insoluble precipitates. Floccula-
tion then promotes the precipitates to
agglomerate or clump together which facilitates
their subsequent removal by filtration.
During this chemical process, the filtered
material or sludge will be collected and stored
in a dumpster and will have to be hauled off-site
for treatment (tt required) and disposal in ac-
cordance with applicable regulations.
Cost: Total present worth:$ 5,300,000.
REMEDIAL ALTERNATIVES TO
ADDRESS SOURCE CONTROL
The remedial action must address contaminant
source areas that currently are accessible to the
public, or that become accessible during the
remedial action. These must be remediated to the
extent necessary to reduce the risks attendant to
exposure to chemical residuals, or they must be
isolated to prevent exposure. The response actions
to address source control at the Potter's Pits Site are
presented in seven different alternatives.
SC-1: No Action
In the No Action alternative, no further remedial
actions would occur. A slight level of remedia-
tion may occur through natural processes. Site
soils would not change signtticantly over time,
and would continue to contribute chemicals to
the groundwater. Operating costs would in-
volve review of remedy every five years.
Costs: Total present worth: $140,000.
SC-2: lnstltutlonal Controls
. The lnstltutional Controls alternative would include
the following:
• • The current resident would be moved.
-Those areas of the Site containing soils with
waste constituent concentrations exceeding
remedial cleanup standards would be fenced.
-The fence would be placarded at twenty-five-
foot intervals along Its perimeter with a warning
about Site conditions.
Costs: Total present worth:$ 1,400,000.
SC-3: Soll Removal and Ott-Site Disposal
-9-
This alternative consists of the excavation of
soils (surface and subsurface) that exceed soil
cleanup standards which is approximately
10,100 cubic yards. If the contaminated soil
passed TCLP, soils removed would be
transported to an off-site permitted landfill for
disposal. If the contaminated soil does not pass
TCLP, the soil would have to be treated and
disposed of at a hazardous waste landttill. The
excavation area would be filled with clean soil,
and compacted and graded to original contour.
The aerial extent assumes a 50 ft. by 50 ft. area
surrounding each location exceeding cleanup
levels.
Costs: Total present worth:$ 8,100,000
(Note: This cost does not include costs of
having to treat the soil before disposal.]
SC-4: Soll Stablllzatlon/Solldlflcatlon
Stabilization/solidttication is a treatment tech-
nology that mixes the contaminated soil with
another substance such as cement, kiln dust,
lime, fly ash, silicates, and clay. This admix
converts the contaminants into their least
soluble, mcbile, or toxic form thus minimizing
their potential migration ott-s·rte. This mixture of
material is then placed back where It was ex-
cavated. A low permeabiltty clay cover would
be placed over the stabilized/ solidttied, con-
taminated materials to minimize the potential for
leaching.
Treatabillty Studies would be required to deter-
mine the best admix to use and whether to treat
the soils In-situ or ex-situ .
Costs: Total present worth:$ 5,500,000.
• SC-5: On-Site Incineration
This alternative consists of the excavation of the
contaminated soils, on-stte incineration of the
excavated soils, and disposal of the treated
soils. A transportable incinerator would be mo-
bilized to the srte to perform the incineration.
Rotary Kiln incineration is a process in which
solid and liquid hazardous wastes are fed into a
rotating chamber where they are exposed to
temperatures ranging from 1500 to 3000
degrees Fahrenheit. The heat reduces organic
(carbon-containing) compounds into their basic
atomic elements, for example, hydrogen,
nitrogen, and carbon. In combination with
oxygen, these form stable compounds such as
water, carbon dioxide and nitrogen oxides.
Costs: Total present worth:$ 12,400,000.
SC-6: Soll Washing and Off-Site lncl_neratlon
Soil washing is a batch process in which the
contaminated soils are thoroughly mixed with
successive rinse solutions formulated to
remove waste constttuents from the soils. Acid
rinses are frequently used to solubilize metals,
transferring the metals from a sqlid or sorbed
state to an aqueous phase. The aqueous
phase is then separated from the solid matrix by
decanting. The rinsate from this step is then
treated using conventional wastewater technol-
ogy for metals removal, such as pH adjustment,
flocculation, clarification, and dewatering.
Process waters would be temporarily stored in
on-site tanks until recycled.· Wastewater
sludges would be dewatered and stockpiled.
Dewatered sludges would be transported to a
RCRA-approved facility for treatment and
landfilled in the event waste characterization of
the sludge materials indicated they were a char-
acteristic hazardous waste.
Costs: Total present worth is$ 12,300,000.
SC-7: Low Temperature Thermal Desorption
and Stablllzatlon
This alternative consists of excavating con-
taminated soil and treating it by thermal desorp-
tion. Treatment would consist of volatilizing the
organic contaminants at temperatures usually
between 300 -1000 degrees F, wtth the off-
gases being treated to prevent the release of
• contaminants. The waste stream would be
treated by stabilization ff needed.
Costs: Total present worth:$ 4,700,000.
EVALUATION OF ALTERNATIVES
The following summary profiles the performance of
the preferred alternatives in terms of the nine evalua-
tion crtteria .noting how tt compares to the other
alternatives under consideration. ·
The following comparative analysis is provided for·
the groundwater remediation alternatives and the
soil remediation alternatives.
Groundwater Remediation:
The following alternatives were subjected to detailed
analysis for migration control:
GW -1: No Action
GW -2: lnstttutional Controls
GW-3: Groundwater Recovery and Treatment
Oyerau Protection: Under potential future condi-
tions the No Action alternative would not address
contaminant levels in_ groundwater, and tt would
allow for possible ingestion of groundwater from
wells drilled in the contaminated area. Since the No
Action alternative does not meet this criteria for
overall protection of human health and the environ-
ment, tt will be dropped from the rest of the evalua-
tion. There is a question with the Institutional Control
alternative on how effective this alternative would be
over time. Alternative GW • 3 would prevent migra-
tion of contaminated groundwater and recover
groundwater to meet the groundwater standards.
CompUance WJth ARARs: MCLs and North
Carolina Groundwater Standards are ARARs for
Stte groundwater. The lnstttutional Controls alterna-
tive would not comply with ARARs. Alternative GW
-3 would reduce the levels of contaminants in the
groundwater and comply wtth ARARs. The treated
water would be discharged into Chinnis Branch and
would meet the respective pretreatment or National
Pollution Discharge Elimination System (NPDES)
permitting limtts. If, at completion of the action,
ARARs cannot be met, a waiver for technical imprac-
-10-
. b.. • tica Ihty would be obtained and groundwater use
restrictions would continue.
Long-Term Effectiveness and Permanence:
Under the Institutional Controls (GW-2) alternative,
groundwater would continue . to migrate off-site;
therefore, it is not considered to be a permanent or
effective remedial solution. Contaminant concentra-
tions would be permanently reduced through
groundwater recovery for Atternative GW-3. Air
Stripping and Chemical Treatment is considered the
best available treatment for heavy metals and
volatile organic compounds in groundwater.
Reduction of Toxicity. Mobility or Volume: The
GW-2 atternative would not signtticantly reduce the
toxicity, mobility, or volume of contaminants in
groundwater. Atternative GW-3 would reduce the
volume of contaminants in the aquifer through
recovery and treatment and comply with the
statutory preference for atternatives involving treat-
ment.
Short-tenn Effectiveness: All of the atternatives
can be implemented without signtticant risk to the
community or on-site workers and without adverse
environmental impacts.
Implementability: None of the atternatives would
pose signtticant concerns regarding implementation.
Construction of the treatment systems would not be
conducted until discharge requirements for the
treated water were defined.
eost: Total present worth tor the groundwater
remediation att_ernatives are presented below:
GW-1: $ 140,000
GW-2: $ 1,400,000
GW-3: $5,300,000
Source Remediation:
The following alternatives were developed tor Site
soils and were subjected to detailed analysis:
SC · 1 : No Action
SC -2: Institutional Controls
SC• 3: Excavation and Off-Site Disposal
SC· 4: Stabilization/Solidttication
• SC· 5: On-Site Incineration
SC -6: Soil Washing and Off-Site Incineration
SC· 7: Low Temperature Thermal Desorption
and Stabilization
Overall Protec)lon: Potential risks due to Site soils
under current and potential future conditions are not
within the acceptable risk range as specified in the
National Contingency Plan (NCP). Alternatives SC-
1 and SC-2 would not decrease the risks associated
with the soils. Atternatives SC-3 through SC-7 would
all decrease the risk and mitigate any further
degradation of the groundwater by leaving the
source in place.
Compliance with ARARs: Al1ernatives sc -3
through SC -7 would meet RCRA closure require-
ments for waste in place tt applicable. Also any of
these atternatives would have to comply with Land
Disposal Restrictions (LDRs) through a treatability
variance or by meeting BOAT standards or
treatability variance levels.
Long-Term Effectiveness and eennanence: Al-
ternatives SC -1 and SC -2 would not be effective
in reducing contaminant levels. Atternatives SC -3
through SC -7 would resutt in a permanent reduction
in Site risks.
Reduction 01 Toxicity. MobHtty. and Volume: Contaminant levels would remain unchanged for
atternatives SC -1 and SC -2. There is a question
to how effective stabilization/solidttication (SC -4)
atternative would be in preventing the organic con-
taminants from migrating on a long term basis. The
rest of the alternatives would reduce or eliminate
contaminant levels, mobility, and the effective
toxicity of the contaminants.
Short-Tenn Effectiveness: Attematives sc -3 through SC -

7

would pose some physical risks to
the workers on-site during the excavation phase of
the cleanup of the contaminated soil. The com-
munity would be protected from short term risk by
dust control measures. The volatilized con-
taminants in atternatives SC -5 and SC -7 would be
treated by an off-gas system.
Implementability: No implementation is needed for
the no action atternative. Off-Site disposal to a
RCRA-approved landfill and incinerator have been
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.1
• conducted successfully at other Superiund Sites.
lrrplementation of Alternatives SC -5 and SC -7
may depend on the av:ailability of a mobile thermal
desorption equipment and mobile incineration
equipment, respectively.
.c&.s:t: Total present worth costs for the soil alterna-
tives are presented below:
SC· 1: $ · 140,000
SC• 2: $ 1,400,000
SC· 3: $ 8,100,000
SC· 4: $ 5,500,000
EPA'S PREFERRED ALTERNATIVE
• SC -5: $ 12,400,000
SC -6: $ 12,300,000
SC· 7: $ 4,700,000
Community Acceptance: Community acceptance
of the preferred alternative will be evaluated after the
public comment period ends and a response·to each
comment will be included in a Responsiveness Sum-
mary which will be a part of the Record of Decision
(ROD) for the Site.
State Acceptance: The State is currently reviewing
EPA's proposed plan.
After conducting a detailed analysis of all the feasible cleanup alternatives and based on the criteria described
in the preceding section, EPA is proposing a comprehensive, multi-<:omponent cleanup plan to address
groundwater and soil contamination at the Site. The EPA preferred alternatives are:
Groundwater Remediation
GW -3: Groundwater Recovery and Treatment
Costs: $5,300,000
Source Remediation
SC • 7: Low Temperature Thermal Desorption and Stabilization
Costs: $4,700,000
TOTAL: $10,000,000
On-Site Incineration, Alterr:ative 5 for Soil Remediation ($12,400,000) has been chosen as a contingency
alternative.
The preferred remedy for soil remediation (Low Temperature Thermal Desorption) will involve some testing
to verify that the cleanup standards can be reached. If treatability studies show that the cleanup standards
cannot be _met, and/or the remedy is determined not to be cost effective in relation to on-site incineration,
then the more conventional incineration technology would be utilized.
Based on current infonmation, these alternatives appear to provide the best balance of trade-offs with respect
to the nine criteria that EPA uses to evaluate alternatives. EPA believes the preferred alternative will satisfy
the statutory requirements of Section 121 (b) of CERCLA, 42 U.S.C. 9621 (b), which provide that the selected
alternative be protective of human health and the environment, comply with ARARs, be cost effective. and
utilize penmanent solutions and treatments to the maximum extent practicable. The selection of the above
alternatives is preliminary and could change in response to public comments.
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• •
COMMUNITY PARTICIPATION
EPA has developed a communrty relations program as mandated by Congress under Superfund to respond to crtizen·s concerns and needs for information, and to enable residents and public officials to participate in the decision-making process. Public involvement activities undertaken at Superfund srtes are interviews wrth local residents and elected officials, a communrty relations plan for each site, fact sheets, availability sessions, public meetings, public comment periods, newspaper advertisements, srte visrts, and Technical Assistance Grants, and any other actions needed to keep the communrty informed and involved.
EPA is conducting a 30-day public comment period from April 30, 1992 to May 30, 1992, to provide an opportunity for public involvement in selecting the final cleanup method for this Stte, and the use of a Trealability Variance to comply wtth LDRs for each of the alternatives for which one is required. Public input on all alternatives, and on the information that supports the altern.:itives is an important contribution to the remedy selection process. During this comment period, the public is invtted to attend a public meeting on May 12, 1992, at the Hood Creek Comrnunrty Center, Sandy Creek North Carolina beginning at 7:00 p.m. at which EPA will present the Remedial Investigation/ Feasibility Study and Proposed Plan describing the preferred alternative for treatment of the contamination at the Potter's Septic Tank Service Pits Stte and to answer any questions. Because this Proposed Plan Fact Sheet provides only a summary description of the cleanup alternatives being considered, the public is encouraged to consult the information reposrtory for a more detailed explanation.
During this 30-day period, the public is invtted to review all stte-related documents housed at the information reposrtory located at the Columbus County Library, East Columbus Branch, Highway 87, Reigelwood and offer comments to EPA erther orally at the public meeting which will be recorded by a court reporter or in written form during this time period. The actual remedial action could be different from the preferred alternative, depending upon new information or arguments EPA may receive as a result of public comments. If you prefer lo submit wrtt1en comments, please mail them postmarked no later than midnight May 30, 1992 to:
Diane Barrett
NC Community Relations Coordinator
U.S.E.P.A., Region 4
Nonh Remedial Supertund Branch
345 Counland Street, NE
Atlanta, GA 30365
All comments will be reviewed and a response prepared in making the final determination of the most appropriate alternative for cleanup/treatment of the Srte. EPA's final choice of a remedy will be issued in a Record of Decision (ROD). A document called a Responsiveness Summary summarizing EPA's response to all public comments will also be issued wijh the ROD. Once the ROD is signed by the Regional Administrator tt will become part of the Administrative Record (located at the Library) which contains all documents used by EPA in making a final determination of the best cleanup/treatment for the Srte. Once the ROD has been approved, EPA once again begins negotiations wtth the Potentially Reponsible Parties (PRPs) to allow them the opportunrty to design, implement and absorb all costs of the remedy determined in the ROD in accordance with EPA guidance and protocol. II negotiations do not result in a settlement, EPA may conduct the remedial activrty using Superfund Trust monies, and sue for reimbursement of tts costs wrth the assistance of the Department of Justice. Or EPA may issue a unilateral administrative order or directly file sutt to force the PRPs to conduct the remedial activity. Once an agreement has been reached, the design of the selected remedy will be developed and implementation of the remedy can begin.
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• • As part of the Supertund program, EPA provides affected communities by a Supertund sne wnh the
opportunity to apply for a Technical Assistance Grant (TAG). This grant of up to $50,000 is awarded to only
one comrrunity group per sne and is designed to enable the group to hire a technical advisor or consultant
to assist in interpreting or commenting on.site findings and proposed remedial action plans. A cnizens' group
interested in the TAG program needs to submit a Letter of Intent to obtain an application package from:
•
Ms. Rosemary Patton, Coordinator
NC Technl_cal Assistance Grants
Waste Management Division
U.S.E.P.A., Region 4
345 Courtland Street, NE
Atlanta, GA 30365
[phone]
INFORMATION REPOSITORY LOCATION:
Columbus County Library
East Columbus Branch
P. 0. Box 27, Highway 87
Reigelwood, North Carolina 28456
Phone: [phone]
Hours: Monday -Thursday -12:00 -5:00 p.m.
· Friday -10:00 a.m. -5:00 p.m.
Saturday -Closed
Sunday -2:00 p.m. -5:00 p.m.
FOR MORE INFORMATION PLEASE CONTACT:
Ms. Darcy Duin, Remedial Project Manager or
Ms. Diane Barrett, NC Community Relations Coordinator
North Superfund Remedial Branch
Waste Management Division
U.S. Environmental Protection Agency, Region IV
345 Courtland Street, NE
Atlanta, Ga 30365
Phone: [phone]
Toll Free No.: 1-800-435-9233
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• • GLOSSARY OF TERMS USED IN THIS FACT SHEET
Aquifer: An underground geological formation, or group of formations, containing useable amounts of groundwater that can supply wells and springs.
Administrative Record: Afile which is maintained and contains all information used by the lead agency to make tts decision on the selection of a method to be utilized to clean up/treat contamination at a Su-perfund stte. This file is located in the information reposttory for public review.
Appl/cable or Relevant and Appropriate Require-ments (ARARs): The federal and state require-ments that a selected remedy must attain. These requirements may vary among sttes and various alternatives.
Basellne Risk Assessment. A means of estimating the amount of damage a Superfund stte could cause to human health and the environment. Objectives of a risk assessment are to: help determine the need for action; help determine the levels of chemicals that can remain on the stte after cleanup and still protect health and the environment; .and provide a basis for comparing different cleanup methods.
Carcinogenic: Any substance that can cause or , contribute to the production of cancer; cancer-. producing.
Comprehensive Environmental Response, Com-pensation and Llab/1/ty Act (CERCLA): A federal law passed in 1980 and modttied in 1986 by the Superfund Amendments and Reauthorization Act (SARA). The Acts created a special tax paid by producers of various chemicals and oil products that goes into a Trust Fund, commonly known as Super-fund. These Acts give EPA th.e authority to inves-tigate and clean up abandoned or uncontrolled hazardous waste sites utilizing money from the Su-perfund Trust or by taking legal action to force parties responsible for the contamination to pay for and clean up the site.
Decanting. To pour oft wtthout distrubing the sedi-ment; to pour from one container into another.
Downgradlent: The direction that groundwater flows, similar in concept to "downstream" for surface water, such as a river.
Electromagnetic Survey: This survey method provides a means of measuring the electrical con-ductivtty of subsurtace soil, rock, and groundwater.
Ground Penetrating Radar(GPR): Method using high frequency radio waves to acquire subsurtace information. From a small antenna which is moved slowly across the surface of the ground, energy is radiated downward into the subsurface, then reflected back to the receiving antenna. This produces a continuous cross-sectional profile of shallow subsurface condttions.
Groundwater: Water found beneath the earth's surface that fills pores between materials such as sand, soil, or gravel (usually in aquifers) which is often used for supplying wells and springs. Because groundwater is a major source of drinking water there is growing concern over areas where agricul-tural and industrial pollutants or substances are get-ting into groundwater.
Hydrology. The science of dealing wtth the proper-ties, movement, and ettects of water on the earth's surface, in the soil and rocks below, and in the atmosphere.
In-Situ: Means to keep in place, treatment con-ducted in tts original place: ex-sttu is removal from place of origin.
Information Repository: A file containing accurate up-to-date information, technical reports, reference documents, information about the Technical Assis-tance Grant, and any other materials pertinent to the stte. This file is usually located in a public building such as a library, city hall or school, that is accessible for local residents.
Land Disposal Restriction (LDRs): Any place-ment of hazardous waste in a landfill, surface im-poundment, waste pile, injection well, land treatment facility, salt dome formation, underground mine, cave and concrete bunker or vau It.
Leachate: A contaminated liquid resulting when water percolates or trickles through waste materials and collects components of those wastes. Leaching may occur at landfills and may result in hazardous substances entering soil, surface water or groundwater.
-15-
• /Wax/mum Contaminant Levels (MCLs): The max-
imum permissible level of a contaminant in water
delivered to any ·user of a public water system.
MCLs are enforceable standards.
National OIi and Hazardous Substances Contin-
gency Plan (NCP): The federal regulation that
guides determination of the sites to be corrected
under the Supertund program and the program to
prevent or control spills into surtace waters or other
portions of the environment.
National Pollutant Discharge Ellmlnatlon Sys-
tem (NPDES): A provision of the Clean Water Act
which prohibits the discharge of pollutants into
waters of the United States unless a special permit
is issued by EPA, a state or (where delegated) a
tribal government on an Indian reservation allowing
a controlled discharge of liquid after it has undergone
treatment.
National Priorities List (NPL): EPA's list of the
most serious uncontrolled or abandoned hazardous
waste sites identified for possible long-term remedial
action under Supertund. A site must be on the NPL
to receive money from the Trust Fund for remedial
action. The list is based primarily on the score a site
receives from the Hazard Ranking System (HRS).
EPA is required to update the NPL at least once a
year.
• Reasonable Maximum Exposure: Calculation of
the highest exposure to all contaminants at a site that
an individual would be expected to receive under
current and future land-use conditions.
Remedial lnvestlgatlon/Feaslblllty Study (RIIFS):
The Remedial Investigation is an in-depth, extensive
sampling and analytical study to gather data neces-
sary to determine the nature and extent of con-
tamination at a Supertund site; to establish criteria
for cleaning up the site; a description and analysis of
the potential cleanup attematives for remedial ac-
tions; and support the technical and cost analyses of
the alternatives. The Feasibility study also usually
recommends selection of a cost-effective alterna-
tive.
Record of Decision (ROD): A public document that
annou,ir,es and explains which method has been
selected by the Agency to be used at a Supertund
site to clean up the contamination.
Responsiveness Summary: A summary of oral
and written public comments received by EPA du ring
a public comment period and EPA's responses to
those comments. The responsiveness summary is
a key part of the Record of Decision.
Vo/al/le Organic Compounds (VOCs): Any or-
ganic _compound that evaporates readily into the air
at room temperature.
Parts per BIiiion (ppb)!Parts per MIiiion (ppm):
Units commonly used to express low concentrations
of contaminants.
MAILING LIST ADDITIONS
If you are not already on our mailing list and would like to be placed on the list to receive future information
on the Potter's Septic Tank Service Pits Superfund Site, please complete this form and return to Diane
Barrett, Community Relations Coordinator at the above address:
NAME:
ADDRESS:
CITY, STATE, ZIP CODE:
PHONE NUMBER:
AFFILIATION (tt any): ..
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•
MEMORANDUM
TO:
FROM:
File
Charlotte J esneck
Superfund Section
1 April 1991
RE: Potter's Septic Tank Service Pits NPL Site
•
I contacted Steve Norhstedt of the US EPA Region IV at [phone] today to
determine the response to the public meeting conducted on 28 March 1991. Steve indicated
the level of public concern was low and no comments were made. He said that
approximately ten people were present at the meeting.
Mr. Norhstedt did mention he discovered that a property owner has put in a well and
septic tank on a newly developed piece of property in the most contaminated area. Mr.
Norhstedt said that he would work on getting the well in question closed when he visits the
site within the next week.
CVJ/acr