United States
;.'..-.v,'ionrneoiaJ Protection
Agency.
Otic* of
Emergency and
Remedial Response
EPA/ROO/RO3-90/084
December 1989
Superfund
Record of Decision:
Greenwood Chemical, VA
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. .
DICLARATIOH POR TKB RlCORD OP PICISIOH
site Name an4 Looation
Greenwood Chemical site
Albemarle County
Newtown, Virginia
statement of Ba.i. an4 Purpo..
This decision document presents the selected remedial action
for the Greenwood Chemical Site, in Newtown, Virginia, which was
chosen in accordance with the requirements of the Comprehensive'
Environmental Response, Compensation, and Liability Act of 1980
(CERCLA), as amended by the Superfund Amendments and Reauthor-
ization Act of 1986 (SARA) and, to the extent practicable, with
the National Oil and Hazardous Substances Pollution Contingency
Plan (NCP). This decision document explains the factual and
legal basis for selecting the remedy for this site.
The Virginia Department of Waste Management concurs with the
selected remedy. The information supporting this remedial ,action
decision is contained in the Administra~ive Record for this site.
r .
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 ot Decision (ROD), may present an
imminent and substantial threat to public health, welfare, or the
environment.
Desoription ot the S.lecte4 R..e4y
Thi8 Operable Unit is the first of two Operable Units for
the site. !be .elected remedy for Operable Unit One (OU-1) shall
remediate ~taainated soils associated with three (J)former
lagoons ~;. backfill area, and contained chemicals in buildings
which hav*1e8n determined to present a principal threat to human
health and/or the environment a~ the site. The remainder of the
site constitutes Operable Unit Two (OU-2) and includes additional
soil, seqiment, and groundwater. A ~emedy for OU-l is expected
to remove all soil contamination of concern from areas addressed
by the remedy. As a result, long-term management of soils
associated' with OU-1 will no~ be necessary.
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-~L.-=
2
The major components of the selected remedy include' the
, followinq':
o
"Excavation of soil.exceedinq risk-based cleanup levels
(esti=ated at 4,500 cubic yards);
Implementation ot runoff controls durinq excavation;
o
o
Staging and
screening of the excavated soil;
o
Transportation of contaminated soil to an offsite, high
temperature, RCRA-permitted thermal treatment facility
(incinerator) ;
o
Incineration of soil, stabilization of the ash (if
necessary), and disposal of the ash in RCRA Subtitle C
landfill;
o
Backfilling of the excavated areas with clean fill;
Coverage with topsoil and revegetation;
o
o
Removal/disposal of chemicals in onsite buildings.
DeclaratioD of statutory DeteraiDatioD8
The selected remedy is protective of human health and the
environment, complies with Fedetal and State requirements that
are legally applicable or relevant and appropriate to the
remedial action and is cost-eftective. This remedy utilizes
permanent solutions and alternative treatment (or resource
recovery) technologies to the maximum extent practicable, and it
satisfies the statutory preterence for remedies that employ
treatment to permanently and significantly reduce toxicity,
mobility, or volume as their principal element. Because this
remedy will not result in hazardous substances remaining above
health-baaed level. and will permit unlimited use, the five-year
review will not apply to this action.
8.. f3 2.. ~ '-
Regional Administrator
Environmental Protection Ag~ncy
I ~/ z.-t/j¥:; .
, Date
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50272.101
REPORT DOCUMENTATION I I. REPORTNO. . I ~ s. A8cip.nr. AcC888Ian No.
PAGE . EPA/ROD/R03-90/084
4. Tlt18 8nd &Ibfle So Ae,Iort D818
SUPERFUND RECORD OF DECISION 12/29/89
Greenwood Chemical, VA
First Remedial Action I.
7. Author(.' .. Pwfonnin9 OrgMUdon A8tJL No.
e. Pwfonnin9 Orplnildon ..... MIl ~ 10. P\'otICtIT 88111WortI lINt No.
U. c-t(C) 01' Gr8nI(G} No.
(C)
(0)
1~ Spof.-tng 0rg8nIz8IIGn ..... MIl ~ I I. Typ8 of "-'*' . P'IrIod CoWNd
U.S. Environmental Protection Agency 800/000
401 M Street, S.W.
Washington, D.C. 20460 '"
IS. Suppl8m8nt8ry No-
I" Ab8tr8Ct (UnlIt: 2DO WOld.)
The five-acre Greenwood Chemi~al site is a former chemical plant in Newton, Virginia.
Adjoining lands to the east, west, and south are used for ru r a 1, residential and
agricultural purposes, and the Blue Ridge Mountain Range bounds the site to the north.
Ground water is used by all persons within a three-mile radius for drinking water
ur oses. The closest residential well is within 400 feet of the site and the closest
p p . .
iowngradient well is approximately 2,500 feet from the site. The chemical plant was
used primarily for the production of industrial, pesticide, pharmaceutical, and
photographic products from 1947 until 1985, and produced waste solvents including listed
RCRA F002 and F005 wastes. Plant operations were terminated in April 1985, after a
toluene fire killed four employees. Contaminated areas at the site include seven
lagoons used to store wastewaters generated during plant operations, and a buried drum
area. To mitigate threats due to contamination, EPA emergency response activities were
conducted between 1987 and 1988. These activities included removing surface drums and
other stored chemicals: excavating lagoon sludge from three lagoons and stabilizing the
underlying soil before disposing of the treated soil onsite in a lined vault constructed
in one of the lagoons: and capping a lagoon. This operable unit addresses approximately
1.5 acres of the most contaminated portions of the site including the contaminated soil
associated with three of the former lagoons, a backfilled (Continued on next page)
17. DOCUIII8fII ANly8i8 .. D88cripto,.
Record of Decision - Greenwood Chemical, VA
First Remedial Action
Contaminated Medium: soil
Key Contaminants: VOCs (benzene, PCE, TCE), other organics (PAHs), metals (arsenic),
other ino~nics (cyanide)
b. Id8nlitl8rslOp8n. T-
--.
c:. COSA11 FI8IdIGroup
II. S8Nity CI- (Thi. A8pott)
None
20. S8curtty CI- (11118 P808)
Nnnl'>
21. No. 01 Page.
}. Avail.bility 51..--
I
59
22. Price
(See A.~Z3e.18)
See /".trucfi- on Re-
212 (4-77)
(Formerly NTIS.35)
Depet1men1 01 Co-
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,
EPA/ROD/R03-90/084
Greenwood Chemical, VA
16.
Abstract
(Continued)
lagoon now referred to as the backfilled area, and contained chemicals in the
buildings. A second operable unit will address the remainder of the site including
additional soil and sediment, and ground water underlying and downgradient of the
contaminated soil. The primary contaminants of concern affecting the soil are VOCs
including benzene, PCE, and TCE; other organics including PAHs; metals including
arsenic; and other inorganics including cyanide. .
The selected remedial action for this operable unit includes excavation and offsite
incineration of approximately 4,500 cubic yards of contaminated soil,' backfilling. with
clean soil, and revegetating; removal of chemicals stored in onsite buildings; and
surface water cOllection/diversion during remedy implementation. The estimated
present worth cost for this remedial action is $8,787,900. There are no O&M costs
associated with the remedy tor this operable unit.
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. .
3
Table of-Contents
paqe
I.
Site Description
4
II.
Site History
Highlights of Community Participation
5
II I.
9
IV.
Scope and Role of Operable Unit or
Response Action within Site Strategy
9
V.
contaminant Sources of OU-1
10
VI.
Contaminant Migration
18
VII.
Summary of Site Risks
22
II I I.
Remedial Action Objectives
31
IX.
Description of Alternatives
3J
X.
Comparative Analysis of Alternatives
Selected Remedy
37
XI.
44
XII.
statutory Determinations
49
XIII.
Responsiveness Summary.
Appendix
Note: Portions ot this document have been adapted from a Focused
Feasibility Study (FFS) for the Greenwood Chemical Site, as prepared for
the EPA by Ebasco Service~, Inc. in August 1989.
.'
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4
. I.
SITE DESCRIPTION
. .
. The Greenwood'~hemical Site is located in Albemarle County,
. 'between Waynesboro:and Charlattesville, Virginia.' The site
comprises,approximately five (5) acres at the foot of the' Blue
Ridge Mountain Range (Figure, 1). Although the ~ite is located
less than 1/4 mile from Interstate Route 64, access is from Route
690 via Routes 250 and 796. The site entrance is near the center
of the small village of Newtown, Virginia. The site is bounded
by Route 690 and an east/west residential road to the north.
Adjoining lands to the east, west, and south are mixed-use rural,
residential and agricultural. The site slopes to the south-
southeast.
A small tributary to stockton Creek runs approximately 500
feet west of the site. In addition, a farm pond is located
approximately 300 feet downgradient of the site. The depth of
ground water underlying the site averages about 25 feet. All
persons within a J-mile radius use ground water for drinking
water purposes. The closest residential well is located 400 feet
from the site, while the closest downgradient well is
approximately 2,500 feet from the site.
The layout of the site is shown in
features include three primary chemical
former lagoons and a former buried drum
5 contain liquids at this time.
Figure 2. The main
process buildings, seven'
area. Only Lagoons 4 and
operable Unit One (OU-1) comprises approximately 1.5 acres
located on the slope leading southward from the former process
buildings (Figure 2). OU-1 includes components of the Greenwood
Chemical site which are believed to be a principal threat to '
human health and the environment. The specific components of OU-
1 are containers of chemicals stored in the process buildings,
and contaminated soils associated with former Lagoons 1,2, and J
and Backfill North. .
Leftover chemicals formerly used in the manufacturing
processes by the Greenwood Chemical Company are stored in drums
and containers in the process buildings. An inventory of the
drums and containers was conducted by The Environmental
Protection Agency (EPA) ,in June 1988 and confirmed by EPA during
inspections in June 1988 and June 1989. All the drums and
containers in the buildings have been sorted by EPA in accordance
with their chemical characteristics.
, ,
"
.;..
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5
II. . SITB HISTORY
Since the onset of operations'in 1947,. a variet;y of chemical
products with applications in industrial, pesticide, pharma- .
ceutical, and photographic processes have been manufactured at
the site. Manufacturing operations ceased in 1985. . A complete.
. list 'of chemicals produced since 1947 is not available.
Primary products produced have included alpha naphthalene
acetic acid, 1-naphthaldehyde, and naphthoic acid. .Chemicals
used in the production of naphthalene acetic acid included
naphthalene derivatives, sodium cyanide, sulfuric acid,
paraformaldehyde and hydrogen peroxide. The naphthalene
derivative reportedly was reacted with sodium cyanide under
alkaline conditions. In addition, inorganic arsenic salts were.
used onsite as catalysts in producing chloromethylnaphthalene,
while dimethyl pyridine was used as a catalyst in the synthesis
of polyurethane.
During the final years of operation (1982 to 1985), various
naphthalene and benzene derivatives were produced and/or used in
chemical processes.' One of the three main buildings (Building C)
was reportedly used for the following purpose:. .
o
Production of naphthaldehyde via a proprletary process
o
Purification of the sodium salt of beta-naphthalene-
sulfonic-aci<1
o
Production of 2-benzoylpyridine by reacting 2-
cyanopyridine in a solvent. of monochlorobenzene
. .
o
~issolution of organic powder in toluene via another
proprietary process
Waste solvents generated by the latter two processes are
categorized as listed RCRA F002 and F005 wastes, respectively.
A list of chemicals used at the site between 1982 to 1984
was supplied by the Greenwood Chemical Co. to the Virginia Bureau
of Toxic Substances. According to this inventory, between 10,000
and 100,000 kg of toluene and one-to-ten tons of cyanide per year
were utilized by the Greenwood Chemicals Company during this time
period. A list of 32 products was also supplied by Greenwood
Chemical Co. This list contains products for sale and includes
intermediate and final 'products related to pharmaceutical
manufacturing, the agriculture industry, and the general
synthesis of other products.
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o
.
.
.:
TO CHARlOTTESVIL1.1
:>
~
au...DWPItU ~TICII
QRIENWOOO CHEMICAL SITE
ALIIMA"LI COUNTY. VIRGI~.A
S..,.
f.,.,
SITE LOCATION MAP
---
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. 1001
. tOO.
. ".200r
2011
Figure 1
SOURCE: USGS We,,,.....,. E..,. VA 0....."...
-------
1X~t.ANATION
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I
QRI.NWOOD CH.MICAL IITI
ALI.MARLa C~UNT". VA
SITE LAYOUT'
ate
I
JOe
,
SCALI
,......
Figure 2
.. .,.,It
..
"
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8
During the.initial period of operations, wastewater from the
rnanufactu~ng activities was discharged into a small lagoon which
has since been backfilled. 'The EPA has designated this former
lagoon Backfill North. Following closure of the Backfill North,
lagoon, wast-ewater from Building A was directed to Lagoon 1,
while ,wastewater from Buildings Band C reportedly entered Lagoon
, 2., ~en these lagoons reached a predetermined level, wastewater
was allegedly' routed into Lagoon 3 through overflow pipelines.
~goons 1,2, and 3 did not incorporate any processes to aid in
, the breakdown of waste,organic chemicals. Wastewater from Lagoon
J was routed to Lagoon 4 ~nd then to Lagoon 5. Lagoon 5 had
spray devices to aid evaporation in order to prevent overflow.
All fiva lagoons were unlined. In 1978, the lagoons were
reportedly drained and bentonite liners were installed. Details
concerning the construction methods, materials, or thickness of
these liners could not be determined from available information.
The Greenwood Chemical Co. was not classified by EPA or the
Commonwealth of Virginia as a treatment, storage, or disposal
facility under RCRA. In addition, at no time was the facility
regulated under the NPDES program of the Federal Clean Water Act.
The facility was issued a NO-Discharge Certificate by the
Virginia State Water Control Board (SWCB) pursuant to the
Virginia State Water Control Law.
Operations at the plant were terminated iO April 1~85 when a.
toluene fire" killed four workers. A preliminary Assessment and a
Hazard Ranking were performed in May and November 1985,
respectively. The site was promulgated asaNat~onal Priorities
List (NPL) site in July 1987. ' .
EPA emergency response activities took place at the Greenwood
site over the next 18 months (1987-1988). .
Specific details pertaining to removal activities conducted in
1987/1988 associated with OU-1 include:
o
A significant number of surface drums were removed
from the site .
o
Remaining drums and containers in the buildings were
examined, inventoried, overpacked and stored for future
removal/disposal
Potentially explosive materials detonated on the site.
o
o 'Sludge from Lagoons 1,2 and 3 was excavated .and disposed
of offsite. Underlying, highly-contaminated soil from
Lagoons 1,2, and 3 was stabilized with kiln dust, .
excavated, and placed in a lined vault in Lagoon. 3
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9
After excavation of contaminated sludge and soil, Lagoon
1 was covered with 3-to-4 feet of clean soil obtained
from a borrow area west of Lagoon .1.
A Remedial Investigation/Feasibility Study was initiated in
October 1988. A "Focused Feasibility Study (FFS) addressing OU-1
was completed in August 1989.
o
III.
HIGHLIGHTS or COKKUNITY PARTICIPATION
The Focused Feasibility Study (FFS) Report and the Proposed
Plan for the Greenwood Chemical site were released to the public
for comment on August 24, 1989. These two documents were made
available to the public in both the Administrative Record and in
an information repository maintained at the EPA Docket Roqm in
Region III and at the Crozet Branch of the Jefferson-Madison
Regional. Library in Crozet, Virginia.. The n~tice of availability
. for these two documents was published in The Charlottesville
DailY Proqress on August 24, 1989. A public comment period on
the documents was held from August 24, 1989 to October 24, 1989.
In addition, a public meeting was held on September 12, 1989. At
this meeting, representatives from the EPA answered questions
about problems at the site and the remedial alternatives under
consideration. A response to the comments received during this
period is included in the Responsiveness Summary, part of this
ROD. .
IV.
SCOPE AND ROLE or OPERABLE UNIT OR RESPONSE ACTION WITHIN
SITE STRATEGY
. As with many Superfund sites, the problems at the Greenwood
Chemical Site are complex. As a result, EPA has organized the
. remedial work into two Operable Units. Operable Unit One (OU-1)
addresses contaminated soil associated with Lagoons 1,2, and 3
and Backfill North. EPA has determined that these soils
constitute a principal threat at the site. In particular, this
soil has been determined to present an unacceptable risk from
potential direct contact and an unacceptable risk to potential or
known consumers of groundwater. Operable Unit Two (OU-2)
includes remaining soil/sediment and groundwater/surface water.
This ROD addresses OU-1, while a follow-up ROD will address OU-2.
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10
v.
Sources of contamination in OU-1
Lagoon 1
During EPA removal activities in 1987 and 1988, contaminated
sludges from Lagoon 1 were excavated and removed from the site.
Contaminated soils pelow the sludge remained t~ be addressed by
means of a remedial action. The 'Lagoon 1 excavation was
backfilled with clean site soils in the interim. The area of
Lagoon 1 is an estimated 1570 square feet. .
Sixteen (16) soil samples have been collected and analyzed
from Lagoon 1. . Five (5) of these samples were collected during
USEPA removal activities at the site in December 1987; the
remaining eleven (11) samples were obtained from two soil borings
(B6 and B7) completed in Lagoon 1 in December 1988, during the
RI/rS field program performed by EPA.
Analytical results for significant contaminants detected in
Lagoon 1 soils are summarized in Table 1. The complete
analytical results are summarized in Appendix A of the FFS.
These results reveal elevated levels of benzene, methylene
chloride, tetrachloroethene,and arsenic from.O to 4 {eet in depth
from interface of the fil! and the original soil profile.
Samples collected from 4 to 15.5 feet from this interface
revealed highly elevated levels of ~oth volatile and semi-
volatile Tentatively Identified Compounds (TICs). The semi-
volatile TIC naphtaleneacetonitrile was detected at estimated
levels of up to 5500 mg/kg within this zone. Table 1-A
summarizes estimated maximum concentrations of selected
Tentatively Identified Compounds detected in OU-1 soils, i.e.,
soils of Lagoons 1, 2, and 3, and Backfill North.
Lagoon 2
soil samples were collected from Lagoon 2 during EPA removal
activities and the RI/FS field program. Five (5) soil samples
. were collected from surface (0-2 feet) and near-surface (2-4
feet) soils in December 1987; five (5) additional soil samples.
were obtained from a soil boring (B5) completed in January 1989.
Selected results for the indicator contaminants are presented in
Table 2. The complete analytical results for Lagoon 2 soils are
summarized in Appendix A of the FFS. The area of Lagoon 2 was
'approximately 2,356 square feet. .
Elevated levels of benzene, methylene chloride,
tetrachloroethene and arsenic were detected in soils at least to
q depth of four feet within this area. In addition, elevated
levels of the volatile TIC tetrahydrofuran were detected in soils
up to 20 ~eetin depth. ' .
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Table)
OOMCUI.AIIWIS Of I.ICAIOI CU8IMIIWIIS II lAliOCl8 I SOil
GrcenNOOd the8j,.1 Sit., AI~I. to., Vlr,lnl.
hee".. IIIJI IIISl Ill)) 14 I J4 IS 16 16 " 16 11 .., 16 " 16 "
..... ...". 4-' 4-' '-I 6.1 6.1 6-1.~ 8-'.~ t'IO.~ 10-1I.~ ' 10. S -11 ll'U.~ 14 'IS. ~ 15-16.S 11'19.5 18-19.5 21-1
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......'c 4S.1 JrI ".J )'.4 19l 1.1 . 2 . 6.4 . 4.) . ).J . 2.1 . J.t . 1.1 . 6.) . S.).
...- I.)ft s.ns 1.W 1.D6l c).2 cJ.2 44.1 411.) c1.1 c2.) c).) cl.1 cl cO. as 4
D'''''''''- 16.111 11.6M 2.", B.MS J.21 cl.2 cJ.l 44.1 cJ.) c1.1 cl.) 411.) 41.1 cl cO. as
.
cw-,. 1.181 1M.' 2n.2 4ri.4 JJ4.' c1.l I.SS 1.08 411.1 1.16 I.) cl.1 el.l el.l . cl.0 c
......- ~,...,. I.J\I '.IM I.JOI S."I 1.6Z1 1.)" 1.1" 2.4" I.t.. 1.1" 1.2" c).S 0.14 .. cl 0.)9~' 41
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,...1 --.11'. liCe ) 4 II 1.1 1.2
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." C8IIC8ntr.."- In IllAI CfII8)
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12
.Tab1e 1-A
Estimated Maximum Concentrations of
Selected Tentatively Identified Compounds (TICs)
Detected in OU-1 Soils
l-Naphthaleneacetic acid
l-Naphthalene acetonitrile
l-Napnthalene carbonitrile
N,N-Dimethyl-benzeneamine
Phenyl-2-pyridinyl methanone
N-Methyl-benzeneamine
2-Amino-5-chlorophehyl-phenyl-methanone
5H-indeno (1,2-b)pyridine
Unknown Napthalene derivatives
~otals unknown concentration
Source:
Appendix A, Focused Feasibility Study
mq/kg
770
14,000
500
600
4,000
200
5,000
880
1 ,.700
2,400
. .
. .
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\
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COMei.IU' 1~5 Of 18I01CA'0I U.U"'11WI15 I. UCiOOII 2 $OIL
'reen...ood a.C8lcei $i.'., A'~'. Co., Viruini.
I
I
I.
I,'
l..' Ian 161 IS 11116 111J1 19111 20 .~ .~ .~ .~ .~
..... ::t" 0.2 0.2 2'4 2-4 2,4. 4'~.S 6-1.S 1'9.S 12.n.~ 20,20.9
..SlMa/PAlMUII ..,. .. .... .. 12/" Ill81 12181 12/" 12/" 1189 1/89 1/89 1/89 I/S/89
Anenle 41. 100. 44 . SOO 12.200 ZJ.400 )4.400 2.000 2.400 2.100 I. 100. 1.400.
....- I.. 0.180 1.420 O.SOJ 0.006 0.011 0.024 0.012 O.~O 0.016
OIIor---- IS. tOO 9.~ 1.220 ..~ 4.no 0.021 0.~9 0.010 O.OH 0.010
Cy8n1. 409. JOG 421.600 SI.41O 41.140 )l.no 114.000 469.000 111.000 21. ~oo 2.400
"'III~I- ell I or I. 1.140 I.SSG 0.120 0.160 0.J~9 0.01), O.~' O.GOS' 0.009' 0.001'
'.I,.IIIoroelh8n8 0:910 0.161 1.290 4.192 0.810 40.001 .0.001 .0.001 40.001" .0.001
1r8~Ioroel"" 0.016 40.001 40.001 .0.001 .0.001 .0.001
101.1 lel PAIl. 221.S61 IZJ.UO ~4. 110 0.1l I.SO 1.10 O.H O.SS
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-------
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~eenwood Ch88ical Slla, AIb888rle Co., Vir,ln.a
S8IIIpla 81u1ber )O 26 21 28 29 U)-I Sl)-2 21 &)9 2) & 40
S8IIIp~8 Oepl~ Vaull Vaull Vaull Vaull Vaull Wau' I Vaull 8'10 ',10
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Cy.I. 48.)9 11.14 6J.. ~'.6a m.sl 14. ~I 1.~) 29.14
"I~yl- ~I...I. 2.142 l.n4 O.UI O.J9S O.SI4 c210 e.1 I .0.218 0.419
I.'r~I"'''I~ 4.044 1.1 1. OIl 0.162 0.024 c210 10 J 0.009
Ir 1"'1.......... 0.~9 c210 ..)0
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-------
TilLIe 4
eOlieUI UII &:*5 01 IIIUCAIOI C&:*IM11IWI15 I. lAeUIH _I" SOil"
'reenwood Ch88,c.I SIC.. 'Ib888rl. Co.. vlr,lnl.
lOCA II &:* IIJ II' 12 12 IIJ 12 12 12
...,.. DepC" 0-).\ 4,6 4-6 6-7.) 6-8 10.H.) 14-1).) 11.\-19
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Anenle UJ .., 11.6 6 I 496 4.6 I J I 6.S I
1enI- .0.86 cO.84 0.017 .I cO. 19 cO.9O cO.12
OIOlab8n&- 40.16 cO.84 cO. 19 40.90 cO.12
ey8fllde U JU 7.S 1.2 16 S.' 1.1 I.J
"c"yl- Chloride 0.048 I cO. '16 cO.84 cO. 19 cO.9O cO.12
I.CF~IoroaChen8 cO.16 cO.84 cO.19 . 40.90 cO.'2
.Itldal«oal"" 40.16 cO.84 cO.19 cO.9O cO.'l
1oc.' In ,All. O.sa 0.48 J60 490 0.S9 11 9.2 o.n
I.c.' Vo,.cl'. IIC. (80n8 deC_Ced).
loc.a lealvoa.cla. IIC. I7talJ 1690 ll61 1~9 JOJ ,.1
J18 199
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. "
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.'
-------
17
Lagoon 3
Fifteen (15) soil samples were collected and analyzed from
Lagoon 3 during ~emoval activities in December .1987 and April
1988, and the RI/FS field program in December 1988. Seven (7) of
these samples represent the contaminated materials excavated from
Lagoons 1,2, and 3 and encapsulated in the "vault" constructed in
the Lagoon 3 excavation. The materials stored within the v.ault
have been classified as soils based on site observations. In
particular, sampling in December 1988 confirmed that there were
no sludges observed in the vault, only dry to slightly moist,
silty clay with gravel and small kiln dust concretions.
The remaining eight (8) soil samples from Lagoon 3 were
obtained from the 8-12 foot depth interval, which corresponds to
the first four feet of soil underlying the vault. Selected
results for the indicator contaminants are presented in Table 3.
The complete analytical results for Lagoon 3 soil samples are
summarized in Appendix A of the FFS. The area of Lagoon 3 is an
estimated 3,024 square feet.
Soils within the vault were found to contain elevated levels
of benzene, tetrachloroethene, methy~ene chloride and arsenic.
In addition, fifteen (15) volatile/semi-volatile TICs were
detected in these soils. Total semi-volatile TICs were detected
at levels up to 14300 mg/kg. Soils up to four feet below.the
bottom of the vault were found to contain elevated levels. of
methylene chloride.
Backfill Nortb
A total of eight (8) soil samples were collected from. the
Backfill North (BFN) area. Three (3) samples were obtained from'
a boring of 8 feet completed during the September 1987 interim
field investigation. . The remaining five samples were collected.
from a 19-foot-deep boring drilled in February 1989'for the RI/FS
field 'program.
Summarized results for the indicator contaminants detected
in these eight (8) samples are presented in Table 4. Complete
analytical results for BFN soil samples are summarized in
Appendix A of the FFS. The area of Backfill North is an
estimated 570 square feet.
.
containerized Chemicals
Chemicals formerly utilized in chemical processes onsite
remain stored in onsite process buildings. An inventory of the'
chemicals of concern has been compiled by EPA and verified' by EPA
periodic inspection. The inventory includes an estimated 400
containers of chemicals, ranging in volume from 60 milliliters to
55 gallons. The identity of these chemicals has been determined
-~ to be business-confidential information. However, EPA's analysis
of this inventory has determined that the chemicals of concern
-------
18
'ate either carcinogenic or toxic, and present a threat to human
health. from dermal contact or incidental ingestion.
VI.
CONTAMINANT MIGRATION
Sampling during RI/FS activity.has revealed significant
contamination of groundwater underlying and downgradient of
contaminated soils associated ~ith Lagoons 1,2 and 3 and Backfill
North. Figure 3 indicates the location of monitoring wells,
while. Table 5 summarizes the results of., sampling conducted by EPA
in February 1989. . . . .
Sampling of Monitoring Well 100, '~ocated immediately south
of former Lagoon 1, revealed significant concentrations of
benzene, chlorobenzene, tetrachloroethene and semi-volatile TICs.
Sampling of Monitoring Well 185 and 180, located approximately
150 feet downgradient of Lagoon 2 in the direction of groundwater
flow (to southeast) revealed significant concentrations of
benzene, ch10robenzene, trichloroethene, semi-volatile TICs and
volatile TIC's.
As previously indicated, all persons within a three-mile
radius of the site currently utilize groundwater for drinking
water purposes. The closest'downgradient residential well is
located approximately 2,500 feet from the site. In addition, all
residential wells within a 3-mile radius of the site are
potentially hydraulically connected to ground water underlying
the site. The referenced sampling results indicate contaminated
soils associated with Lagoons 1, 2, and 3, and Backfill 'North
~ave contaminated ground water underlying and downgradient .
(southeast) of the site. In addition, while contaminated
groundwater is not known to have impacted surface water through
recharge, this is a pathway of potential concern. A remedy
addressing contaminated groundwater shall be selected in a
follow-up ROD for OU-2.
-------
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GRIINWOOD CHIMICAL liT I
ALIIIIARLI COUNTY. VA
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-------
22
VII.
SUMMARY OP SITE RISKS.
A 'Baseline Risk Asses~ment has been performed to estimate.
the risk to human health posed:by contaminated soils ~n aU-l.
Based on RI data, the soils of concern were determined to present
a potential risk to human health by contamination of groundwater
(and subsequent ingestion of groundwater by'persons potentially
residing at or near the site boundary) and from direct contact by
potential future residents. . The Baseline R~sk Assessment has
therefore estimated risk posed, to human health by contaminated
soil in QU-1 through these two pathways. .
Eleven (1.1) chemicals/substances were selected as primary
chemicals/substances of concern: benzene, trichloroethene,
chlorobenzene, tetrachloroethene, methylene chloride,
noncarcinogenic polycyclic aromatic hydrocarbons (PAH)
(represented by naphthalene), naphthalene acetic acid,
naphthylacetonitrile, tetrahydrofuran, arsenic, and cyanide.
These chemicals were found at relatively high concentration and
frequency in site soils.
The organic chemicals, benzene, methylene chloride,
tetrachloroethene, and trichloroethene represent the volatile
carcinogenic solvents, while chloroben,zene, methylene chloride
and tetrachloroethene ,'represent the vol&tile 'non-carcinogenic
solvents. Naphthalene represents the measured constituents of
the non-carcinogenic semivolatile class of.PAH.
. .. '1
"
. .
Naphthalene acetic acid, naphthylacet~nitrile, and
tetrahydrofuran are several of many tentatively identified
compounds (TICs) that have been observed at the Greenwood Site in
relatively high concentrations. These par.ticular compounds are
expected to exhibit non-carcinogenic chronic systemic toxic~ty;
however, the actual toxicological implications of these and other
TICs are difficult to assess due to the paucity of data available
concerning these chemicals. Methylene chloride and tetrachloro-
ethene are represented in both of the groups because they have'
been shown to exhibit both carcinogenic and non-carcinogenic
effects. For the inorganic chemicals of concern, arsenic
represents carcinogenic metals and cyanide represents
noncarcinogenic anions.
-------
23
To facilitate estimation of risk posed by the soils of
concern to potential consumers of groundwater at or near the site
boundary, mean and maximum concentrations of the primary
contaminants of concern in OU-l soils were calculated. These
concentrations appear in Table 6. A soil leaching model was then
used tO,estimate,the resultant cOncentrations of these compounds
-in ,groundwater at the site ,boundary. The model of concern is
described in AppendixD of the FFS. Estimated mean and maximum
concentrations of these compounds in groundwater as calculated
via the model are presented in Table 7.
Utilizing the mean and maximum concentrations in Table 7, an
excess upper bound lifetime cancer risk and ratio of chronic
daily intake (DI) to reference dose (RFD) were calculated fo~
carcinogens and non-carcinogens, respectively. Botn average and'
plausible maximum risks and r~tios. were calculated. Cancer.
potency factors were used to calculate carcinogenic risk~ The
estimated risks of concern are summarized in Table 8,
Cancer potency factors (CPFs) have been developed,by EPA's
Carcinogenic Assessment Group for estimating excess lifetime
cancer risks associated with exposure to potentially carcinogenic
chemicals. CPFs, which are expressed in units of (mg/kg-day)~
are multiplied by the estimated intake of a potential carcinogen,
in mg/kg-day, to provide an upper-bound estimate of the excess'
lifetime cancer risk associated with exposure at that intake
level. The term "upper bound" reflects the conservative estimate
of the risks calculated from the CPF. Use of this approach makes
underestimation of the ~ctual cancer risk ~ighly ~nlikely.
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 non-carcinogenic effects. RfDs, which
are expressed in units of mg/kg-day, are estimates of lifetime
daily exposure levels for humans, including sensitive
individuals, that is not likely to be without an appreciable risk
'of adverse health effects. Estimated intakes of chemicals from'
environmental media (e.g., the amount of a chemical ingested from
contaminated drinking water) can be compared to the RfDs. RFDs
are derived from human epidemiological studies, or 'animal studies
to which uncertainty factors have been applied (e.g., to account
for the use of animal data to predict effects on humans). These
uncertainty factors help ensure that the RfDs will not
unde~estimate the potential for adverse non-carcinogenic effects
to occur.
-------
24
Excess lifetime cancer risks are determined by mUltiplying
the intake level with the cancer potency factor. These risks are
probabilities that ~re generally expressed in scientific notation
(e.g., lxlO'6). An ~xcess lifetime cancer risk of lXlO'6
indicates that, as a plausible upper bound, an individual has a'
one-in-one-million chance of developing cancer as a result of
sit~-related -exposure to. a carcinogen over a 70-year- lifetime
under the specific exposure conditions at a site. -
Potential concern for non-carcinogenic 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 ~ontaminant concentration in a given medium to the
contaminants.' s reference dose). By adding the HQs for all
contaminants within a medium, or across all media to which a
given population may reasonably be exposed, the Hazard Index (HI)
can be generated. The HI provides a useful reference point for
gauging the potential significance of multiple contaminant.
exposures within a single medium or across media. A Hazard Index
of one (1) or greater would indicate adverse, non~carcinogenic
health impacts could occur.
For certain chemical classes observed at the Greenwood
Chemical site (e.g., polycyclic aromatic hydrocarbons (PAH) and
tentatively identified compounds (TICs), human health information
- is very limited. Because of this paucity of data, it is
necessary to assign ~ representative chemical, having human
health information, to represent the entire chemical group.
Thus, for the purposes of this baseline risk assessment,
naphthalene will represent total PAR on the target compound list,' '-
naphthalene acetic acid will represent total semi-volatile TICs,
and tetrahydrofuran will represent total volatile TICs. -
As reflected in Table 8, leaching of contaminants from OU~l
soils is estimated to result in 9round water which exceeds the
10-6 carcinogenic risk level in both the average (6X10'4) and
plausible maximum (2XIO'z) cases if consumed on a regular basis.
(See Table 6 for soil' contaminant levels used to calculate
average and plausible maximum cases.) The actual carcinogenic
risk associated with this pathway may be between the average and
plausible maximum case. In the case of non-carcinogens, the
calculated hazard index exceeded a value of one for both the
average and plausible maximum cases for the groundwater pathway.
In addition to the ground water pathway, baseline risk due
to direct contact with the contaminated soils of OU-l has -also
been -estimated. - The risk of concern 15 that incurred by
potential future residents o~ the site fr~m incidental ingestion
and dermal contact. The soils of. concern were assumed to be'
those within five (5) feet of the surface. Table 9 indicates the
mean and maximum concentrations .of the contaminants of concern in
surface soils. Table 10 summarizes estimated risk and hazard
index (CDI:RfD) for carcinogens and non-carcinogens. Assumptions
"- and calculations are summarized in Appendix D of the FFS.
-------
Table .,
. 50:::
~?OS~~E ?O:~T ~OSC~~TRA::OSS ~SED :~ :HE
SO:~ ~CH:~C ~ODEt FOR !HE !SCEST:CN
OF GRO~~D ~A:ER ?A~AY (~n mg/kg)
Chemical
~ean Concentration
~aximum Concenc:a:ion
, . Arsenic 26.1 687
! Total Cyanide 22.3 478
i
8.n%ene 0.24 7.30
Chlorobenzene 1. 38 150
~ethylene Chloride 0.23 9.1
Tetrachloroethene 0,51 27.3
Trichloroethene 0.014 0.059
'AHs (naphthalene) 45.9' .3.300
TICs (naphthalene acetic ac id) 1.560 17,600
TICs (t~trahydrofuran) 1. 39 2.50
OJ
.Surface soil concentration. and sub.urfac8 soil concentration. vere combined,
.
-------
25
7able -;
?O!E~~:AL GROt~D~A7ER CONCLV!RAT:C~S AT ~E GR!~\~OOD CH~~!CAL Sr7E
EST:~!ED FRO~ THE SOIL ~EACH!~G ~ODEL (~~ ~g/t)
Chemical
~.an Concentration
~aximum. Concentration
Arsenic O.Oll. 0.37
.Total Cyanide 0.0065 0.14
Benzene 0.014 0.44
Chlorobenzene 0.021 2.3
Methylene Chloride 0.13 5.2
Tetrachloroethene . 0.0070 0.38
Trichloroethene 0.00055 0.0024
PAHs (naphthalene) 0.24 18
TICs (naphthalene acetic acid) 8.3 94
TICs (tetrahydrofuran) 0.70 1. 25
-------
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..-..--...-.- .--..-.---
".
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TABLE 9
CONC~~TION OF CHEMICAlS OF CONCERN DETECTED IN Su~ACE SOILS
AT !HE GRELWOOD CHEMICAL SITE (in mgjkg)
Chellical
Mean Concentration
~&Ximull Concentration
Arsenic 50.3 252
Total Cyanide 60.9 422
Bezuene 0.31 5.39
Chlorobezuen. 6.82 150
M.thylene Chloride 0.73 9.1
Tetrachloro.thene 0.66 4.19
Trichloroethene 0.046 0.059
PAH. (naphthalene) 155 985
T!C. (naphthalene acetic ac 14) 9,210 17,600
TICs (tetrahy4rofuran) ND
. -
Nt) - Not d.at8cte4 in .urfac. .011..
Surface .011.: 0 . 5 fe.e
.
-------
, I
T.. .e 10
(5I1MAIIO UPOStIIl' UO illS« ASSOCIAUO WUH 0111((1 (OIIArI WIIH StIIUU SOIL
II aUllltllS Uti.. 01 f.. 6IUIWOOO C""'CA&. Slfl
a. c:arc:lft088t'l
SOil COIC(IIIAIIOI (8111"'.
--..-.--------------------
, \MIa I""
... ...
c..-
'w.r.
Ar..lc
....-
"t..,"" Ch lor ,.
'.tr-=" 1orGet""
'r"'" ...,.....
101M:
~.03("1
J.III( -I.
, .)11( -II
1.611(-01
4.11(-12
,. ~hOZ
5.."
'.1.."
4.1.."
5."-12
1511MA'I0 CHlOIIC IAll. III~ (COla (8UI""de~a
-----------~---~-----_.__.__._--------~_.._------_.-
IItIOUIA&. IIIIiUIIOI
GlItW. AlSOI'II08
-----------------------
---------------------...
, laul ,.. Ie ,Iau.lbl.
A".r. . ....... A".r. .... ....
1.11(-05 ~. 06( -O~ 119(.06 ~ 98l-06
, -,.-. I . )S( - DI , )Sl.08 I .1. - 06
1.1](-11 .,.'. -01 I l)l-Ol '.16(-06
1."-11 1.0Sl-Cli I W-OI , tJl -01
1.151-11 1."-08 1._-11 I . 401 - II
... ~.rc:'AOg8ftI
. - -- -_.- ..-. -.,.-_._._._-~ ...--.,,-...
[AIICU
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fACie.
(8111..,'..1-1
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ll'I"M( tAMCtl II~
... - -r - ... ... - - - - - " ... . . . ., - ... - .'
, laus Ib I. .
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. - --.-----.-.-
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I . lY .00
Z.tO(-OI
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SOIL COIIC(IIIAII01 (818''''.
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._----------------~~----.-
, 'au. ,.. Ie
.... ....
t511MAIto ~IC GAllI III~ (COl. (88I..tJda,1
----------------------~------_.__._-------_._-----_.
11e1.11M. IIIIiUIiOI
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----_.-----_.----~---.-
----.----------------..-
, lau. ,.. Ie Plau.'bl.
'".r. AI.'" A".r898 .... ...
I.ll(-~ I . 48( .05 lut ,06 , . GOt . O~
1.11(-11 1.111 -05 1.1l(-CII ) S6( O~
1."'-01 , . llf - 01 1.1)1-01 , 16(-06
1.011(-" "'.-14 I .ISl - 05 111(-04
1.'.-11 ~ .'11( -I) 1.151-1) ).)4(-0)
. C...,.
Ch....,..
.th, IBM thlor ,. '.
,.... IMllhthe.....
lie. ..,..... ace. .c: 'd.
IMlMI .1 IOU :
'.0lIl.01
1.11(.01
1.)11(-11
1.51(.01
I.ZI(.I)
4 .12(.02
1 . ~ .01
1.11(.00
1.ISl.OZ
l.llf .04
- -.-_..._.. .-...- .
. -. -. -.---
IU 111118((
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(881"11'.. I
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. . - . .. . - . -
Awcray.
"auslbl.
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.-... ~.. ._-. - .
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"
---. --.., - '-"----
-----
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30
As reflected in Table 10, the primary risk from direct
contact is due to elevated levels of arsenic in surface soils.
The average excess upper bound lifetime cancer risk in this case
is 2x10.S, while the plausible maximum may be as high as 1x10.10
. In conclusion, contaminated soils associated with Lagoons
1,2, and 3, and Backfill North present an unacceptable risk to
human health from both the groundwater' and direct contact
pathways.. It should be noted the risks. identified in Table 8 and
Table 10 should be considered conservative estimates. For
instance, exposure levels may be overestimated and the criteria
for health effects have margins of uncertainty.
A review of available site-related data has not revealed an
environmental risk of concern. Extensive sampling of a tributary
to Stockton Creek located approximately 500 feet from the site
has detected no contaminants associated with the site. One
sampling,event did reveal an estimated 12 ug/l of cyanide in a
farm pon~ located 300 feet south ot Lagoon 5. Although the
source of contamination is uncertain, available information
suggests the source of this contamination is surface runoff from
areas outside the scope of OU-1. Therefore, alternatives to
address this potential problem shall be evaluated as part of
Operable unit Two. No critical habitats, endangered species or
wetlands have been determined to be affected by the site.
Based on the above findings~ actual or threatened releases
of hazardous substances from the site (OU-1), if not addressed by
implementing the response section selected in this ROD, may
present an imminent and substantial endang~rment to' public,
health, welCare or the environment. .
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31
VIII.
REMEDIAL ACTION OBJECTIVES
The objective of remedial actIon that addresses soils
associated with Lagoons 1,2 and 3 and Backfill North' (OU-1) is to
minimize risk to human health and the environment, and in
particular, to minimize exposure from the direct contact--
incidental ingestion and dermal contact--and,ingestion of ground
water contaminated by leachate. migrating from the soils of
concern. Exposure from both of these pathways, under certain
circumstances, may be reduced by placement of a permanent,
impermeable cap over the soil of concern. However,in this case, .
erosional processes induced by the steep terrain characteristic
of the site prevent placement of a permanent cap. Placement of a'
cap which is unlikely to be permanent does not conform with
SARA's preference for permanent solutions. The alternative is
removal from the site of all soil determined to exceed site-
specific, risk-based cleanup levels.
Site-specific risk-based cleanup levels protective of the
groundwater ingestion pathway are presented in Table 11. Target
concentrations protective of this pathway were developed from
models to determine base-line risk. Specific calculations can be
found in Appendix B of the FFS. To avoid exceeding ground water
criteria identified in Table 11, all soils above target
concentrations in this Table will be removed from the site.
all cases, with one exception, criteria protective of the
groundwater pathway are also protective of the direct contact.
pathway. The.exception is arsenic, where a surface soil,
concentration of 25 mg/kg has been determined to produce a
carcinogenic risk of 10'~, while a concentration'of 2.5 mg/kg
corresponds 'to an estimated '10'6 carcinogef1ic risk. Background
levels 'of arsenic, in the eastern United States average an '
estimated 7.4 mg/kg and range up to 7~ ppm. In addition, the
cancer of concern in this case is a non-fatal form of skin
cancer. As a result, 25 mg/kg of arsenic in soil is considered
to be protective and is the target cleanup level for this
substance. .
In
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32 .
Table '11
TARGET CONCE~AATIONS FOR CHEMICALS IN SOIt BASED ON .
THE GROUNDWATER INGESTION.PATHWA~ AT THE GREENWOOD SITE
CHEMICAL
CONCDn'UTION
mq/ kq
OI'I'%1UA
Arsenic 92 MCI.
Benzene 0.083 MCI.
Chlorocenzene 32 WQC
cyanide 520 HA
Methylene chloric!e 0.1 ae.lth-!\..ed
(1 x 10' risk,)
Semi-volatile TIC. .580 a.a.e
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33
IX.
DESCRIPTION OF ALTERNATIVES
The Focused Feasibility Study (FFS) for the Greenwood
Chemical site developed and screened alternatives to address OU-
1. Upon completion of the screening process described in the
FFS, four alternatives were evaluated in detail. The No Action
Alternative was evaluated as required by CERCLA.In addition,
three alternatives involving both treatment and containment were
evaluated. Unlike the No Action alternative, the three treatment
alternatives strive to achieve previously identified remedial
objectives. There are no operation and maintenance (O&M) costs
associated with these three alternatives. ..
Alternative 1:
No Action
Cost (Present Worth): $529,90a.
O&M Cost (Present Worth): $462,600.
Implementation Time: Over 5 years
Under this alternative, no remedial action would be taken
other than (1) groundwater and soil monitoring and (2) re-seeding
of areas disturbed by Remedial Investigation activities. A
program of periodic groundwater and soil monitoring would be
implemented over the next 30 years to evaluate changes in site
conditions over time. Because contamination of OU-l soils will
remain in place, collected monitoring data will be evaluated no
less often than every 5 years. as required by Section 121 (c) of
CERCLA as amended. Similarly, the need for remedial action would
also be evaluated every five.years. Capit~l costs in .this case
cover installation of additional monitoring wells (if necessary) ,0
Alternative 2: Excavation, onsite Thermal Oxidation
(Incineration), Solidifi9ation, and Oftsite Disposal of Residuals
Cost (Present Worth):
Implementation Time:
$7,884,000.
18 to 30 months
Major components.: The major fe~tures include excavation of an
estimated 4,500 .cubic yards of contaminated soil associated with
Lagoons 1,2 and 3, and Backfill North (OU-I), onsite the.rmal
oxidation, onsite stabilization of treated residuals (if
necessary), and/or transport of residuals to an offsite RCRA
Subtitle C landfill.. In addition, containerized chemicals would
be'treated andjor disposed of offsite.
Soils exceeding site-specific, risk-based cleanup levels
would be excavated .and treated onsite in accordance with RCRA
Subpart. 0 standards using a th~rmal oxfdation unit~ 'Where
feasible, contents of contained chemicals would also' be . .
incinerated orisite. The unit would be mobilized, operated, and
closed according to the requirements of RCRA Subpart 0), 40 CFR
264.340.
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34
These requirements are applicable because the soil contains
a RCRA-listed waste. Specific operating practices necessary to
meet the performance objectives, including a 99.99 percent
destruction and removal efficiency (ORE) of stack emissions as
required by Subpart 0 of RCRA, would be determined through a
trial burn at the site after the installation of the thermal
unit. Site-specific air modeling has determined that arsenic
emissions from the thermal oxidation unit could present a risk to
surrounding population without appropriate emission controls.
Therefore, the unit would likely be equipped with a forced flux
condenser and a high-energy collision scrubber to minimize the
. emissions of arsenic and the resultant risk.
Since the soils contain a RCRA-listed waste, the residuals
from the treatment process would be disposed in a RCRA Subtitle C
Landfill after compliance with applicable or relevant and.
appropriate RCRA Land Disposal Restrictions is confirmed.
Because establishment of a Subtitle C landfill onsite is not
technically feasible, an offsite disposal facility shall be used.
Transport of soil residuals must meet all standards
applicable to transporters of RCRA hazardous waste (RCRA Sec.
3003, 40 CFR 262-263 and Virginia State Hazardous Waste
Management Regulations), while the disposal facility must be in
compliance with RCRA Subtitle C Landfill Standards per EPA
.procedures for implementing off site response actions (EPA
Directive 9834.11). Contained chemicals which cannot be
incinerated onsite shall also be transported offsite for
treatment and/or disposal. All soils exceeding risk-based
cl~anup levels shall be excavated and removed from the site.
Therefore, RCRA Clean Closure requirements will have to be met
for all excavated areas by backfilling with clean soil, grading
to promote drainage, coverage with .to~soil, and revegetation to
minimize erosion. (Ground water r~mediation necessary to
complete RCRA Clean C~osure will be selected under OU~2.) Since'
use of soils in the area of concern will be unrestricted, neither
operation and maintenance nor a SARA five-year review will be
necessary.
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35
Alternative 3: Excavation, otf Site Thermal Oxidation
(Incineration), and Off sit. Disposal ot Residuals
Cost (Present Worth):
Implementation Time:
$8,787,900.
16 Months
Major Components: An estimated 4,500 cubic yards of contaminated
soil associated with Lagoons 1, 2 and J and Backfill North would
be excavated and transported to an off.site thermal oxidation.
treatment facility. FOllowing thermal oxidation, residuals would
be stabilized (if necessary) and disposed in a RCRASubtitle C
landfill. containerized chemicals would also be transported off-
site for thermal oxidation and landfilling., . .
Soils exceeding ~isk-based clean~p levels would be excavated
and transported in compliance with standards applicable to
transporters of hazardous waste (RCRA'Sec 3003 40 CFR,262-263 and
virginia State Hazardous Waste Management Regulations) to an
incineration facility. The selected facility would be permitted
and in compliance with all requirements applicable to RCRA
incineration facilities, including 40 CFR 264, SUb-part 0 and CFR
270.124. Specific requirements would include a 99.99 percent
destruction efficiency. If necessary, residual ash remaining
after oxidation would be stabilized/solidified by the permitted
facility prior to disposal in a RCRA Subtitle C landfill.
Excavated areas would be backfilled with clean soil, graded
to promote drainage, covered with top-soil and revegetated.Due
to removal of all soil exceeding risk-based cleanup levels, RCRA
Clean Closure requirements for. the excavated areas will be met.
(Groundwater remediation nQcessary.to.comp~ete RCRA ~lean Closure,
will be .selected under OU-2.) . Since us~ of soils in the area of .
concern will be unrestricted, neither op~ration and maintenance
or a SARA five-year review will be necessary.
~
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36
Alternative 4: Bxcavation, On Sit. Bnhanced Volatilization and
Solidification, Off-Site Disposal
Cost (present worth):
Implementation Time:
$6,558,000.
36 to 48 months
Major Components: An estimated 4,500 cubic yards of contamin~ted
soils associated with Lagoons 1,2 and 3 and Backfill North would
be excavated and treated onsite in an enhanced, low-temperature
volatilization treatment unit. Organic hydrocarbon residuals
collected during treatment would be transported to an off-site
thermal oxidation unit for destruction. Residual soils would be
stabilized/solidified onsite (if necessary) and transported to an
offsite RCRA Subtitle C Landfill for disposal. . The landfill of .
concern would be in compliance with RCRA Subtitle C requirements
per EPA procedures for implementing offsite response actions (EPA
Directive 9834.11). Containerized chemicals would be transported
offsite for treatment and/or disposal.
Available low temperature volatilization treatment systems
are not known to be equipped with a forced flux condenser/high
energy collision scrubber expected to be necessary to minimize
arsenic emissions. . As a result, these controls would have to be
adapted to the treatment system of concern. In addition, bench
and pilot scale tests would be necessary to confirm RCRA Liand
Disposal Restrictions (and corresponding treatment levels) will
be met. Extensive tests would also be required to refine the
design of the system.
Excavated areas shall be backfilled, graded and revegetated.
Due to removal of all soil exceeding ri.k-based cleanup levels,
RCRA Clean.Closure requirements for the excavated areas will be
met. (Ground water remediation necessary to complete RCRA clean
closure will be, selected under OU-2). Since use of soils in the
area of concern will be unrestricted, neither operation and
maintenance nor a SARA five-year review would be necessary.
..
. .
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37
x.
COMPARATIVE ANALYSIS OF ALTERNATIVES
The four remedial" action alternatives described above were
evaluated using- -the following nine evaluation criteria presented
in "Guidance for concfuctin"g Remedial Investigations and
Feasibility Studies Under CERCLA" (EPA, October 1988) 'and EPA
Directive 9355, 3-20, "Draft Guidance on Preparing Superfund
Decision Documents: The Proposed Plan and Record of Decision."
Threshold criteria
-Overall protection of human health and the environment
-compliance with applicable or relevant and appropriate
requirements (ARARs)
Primary Balancing criteria
-Reduction of toxicity, mobility,
-Implementability -
-Short-term effectiveness
-Long-term effectiveness
-Cost
or volume
Modifying Criteria
-Community acceptance
-State acceptance
These evaluation criteria relate directly to requirements in
Section 121 of CERCLA whic~ measure the overall feasibility and
acceptability of the remedy. Threshold criteria must be
satisfied (or ary. ARARs.waiver obtained) in order for a remedy to
be eligible for selection. Primary balancing criteria are used
to weigh major trade-offs between remedies. State and community
acceptance are modifying criteria formally taken into account
after public comment is received on the Proposed Plan-. The
evaluations are as follows:
A. ProtectioD of Human Health and the Environment
A primary requirement of CERCLA is that the selected
remedial action be protective of human health and the
environment. A remedy is protective if it reduces current and
potential risks to acceptable levels posed by each exposure
pathway at the site.
- -
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. 38
1.
Onsite Thermal oxidation, ottsite Thermal oxidation
Both alternatives include excavation and incineration of all
soils exce~ding risk-based clean-up levels. Performance
.objective~ for ~ll operating incinerators, as required by Subpart
o of RCRA, include 99.99 percent destruction. This objective is
expected to' be met in each.case.. Both incineration alternatives
will be equally protective. In each case, residuals may be
stabilized/solidified if necessary to immobilize metals prior to
disposal. Onsite risks from direct contact and groundwater
pathways would effectively be mitigated in both instances.
2.
Enhanced Volatilization
All soiis above risk-based clean-up levels shall be
excavated for treatment. Enhanced volatilization is expected to
significantly reduce concentrations of organic compounds,
particularly the volatile fraction. Reduction efficiency for
semi-volatile organics may not be as high as that for the
incineration alternatives. Solid residuals from treatment would
be disposed off-site. Onsite risks from direct contact and
groundwater pathways would be effectively mitigated.
3.
No ActioD
This alternative would not be protective of human health and
the environment. In particular, contaminated soils would not be
~xcavated, and risks identified previously would remain
indefinitely. Based on. this determination, the "No Action"
,alternative shall not be subjected to further evaluation.
B." Compliance with Applica})le or Relevant and App~opriate
Requirements
section 121(d) of CERCLA requires that remedial actions at
CERCLA sites at least attain legally applicable or relevant and
a9propriate Federal and state standards, requirements, criteria,
and limitations (which are collectively referred to as "ARARs").
Applicable requirements (requirements which mu~t De satisfied
unless one ot CERCLA's waiver provisions is justified) are those
substantive environmental protection requirements, criteria, or .
limitations promulgated under Federal or state law which, while
not applicable to the hazardous materials found at the site, the
remedial action itself, the site location, or other circumstances
at the site, nevertheless address problems or situations.
sufficiently simi'!ar to those encountered at the site that their
use is well-suited to that site. .
,
Significant ARAR's impacting the remedy selection process
are discussed below.
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39
1.
Onsit. Thermal oxidation, ottsite Thermal oxidation
since the soils of concern contain RCRA-listed wastes (F002
and FOOS), RCRA Land Disposal Restrictions (including 40 CFR
section 268) addressing disposal of the excavated soil are
applicable or relevant and appropriate. (See Section XI for more'
details). Thermal oxidat,ion of the soils in an incinerator
meeting RCRA subpart 0 requirements is expected to produce a
solid residue which mee~s all RCRA LDR. In each case, RCRA
Subtitie'C Closure requirements are applicable and would be met
via excavation of all soils exceeding site specific risk-based
clean-up levels. (Groundwater remediation shall also be 'required
to complete RCRA Clean Closure.)
Each alternative is expected to meet all ARAR's under both the
Clean Air Act (including 40 CFR Parts 1 to 99 and 40 CFR 61.01)
and state of Virginia Regulations for t~e Control and Abatement
of Air Pollution (where applicable).
2.
Enhanced Volatilization
c
Prior to disposal of the excavated soil, RCRA Land Disposal
Restrictions (LOR) must be met. After treatment via enhanced
volatilization, the soil is likely to meet applicable treatment
standards for volatile compounds described in 40 CFR 268 and
other relevant and appropriate LOR criteria. An alternative LOR'
compliance option is to obtain a Treatability Variance (see EPA
. Directive 9347.3-06FS). Reduc~ion of semi-volatile compounds to
relevant and appropriate LDR criteria can only be confirmed
through bench and pilot ,scale studies. Should contaminant levels.
in soils not be reduced per LOR ARAR's, the re$idu~l soil may
have to be treated again via alternative means (e.g. ~thermal
oxidation) before it can be disposed. While compliance with 'LOR
cannot be confirmed at this time, excavation of all soil above
risk-based clean-up levels will meet RCRA Subtitle C CleQn
Closure requirements for RCRA units of concern. (Groundwater
remediation shall also 'be required to complete RCRA Clean'
Closure.) As in the case of the incineration alternatives, air
emission ARAR's under both the Clean Air Act and Virginia'
Regulations for Control and Abatement of Air Pollution are
expected to be met.
3.
Reduction ot Toxicity, MObility, or Volume
Thi~ evaluation criteria addresses th~ degree to which a
technology or remedial alternative reduces toxicity, mobility, or
volume of hazardous substances. Section 121(b) of CERCLA
establishes a preference 'for remedial actions that permanently
and significantly reduce the toxicity, mobility, or volume bf
hazardous contaminants over r~medial actions which would not
result in such reductions.
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'10
1.
on.ite Thermal Oxidation, ott.it. Thermal Oxidation
. Both alternatives will reduce the toxicity and volume of
organic contaminants to the maximum extent possible. In
particular, per requirements of Subpart 0 of RCRA, reduction.
efficiency will ,be at least 99,.99%. If necessary,
solidification/stabilizatio~'~anreducethe'mobility of metals
prior to land disposal. '"
2.
Enhanced Volatilization
The toxicity and volume of volatile organic contaminants are
expected to be reduced significantly. Reduction efficiency for
semi-volatile organics, is not expected to be as high and may be
significantly less than that achieved via thermal oxidation. In
the case of both volatiles and semi-volatiles, reduction,
efficiencies are not known at this time. If necessary, metals.
could be immobilized via sOlidification/ stabilization prior to
disposal. organic contaminants collected in the thermal
volatilization unit will be destroyed offsite by means of thermal
oxidation.
D.
Implementability
Implementability. refers to the technical and administrative
feasibility of a remedy, from design through construction,
operation, and maintenance. In all cases, coordination with the
Virginia Department of Waste Management will facilitate
implementability. ' .
1.
ott.ite Thermal Oxidation
. , .
Several incinerators are' already permitted under RCRA t,o
treat the soils of concern. These facilities g~nerally include'
RCRA subtitle C landfills for disposal of solid resi~uals. While
incinerator capacity is not high at this time, several new
facilities within a rea~onable distance 'of the site are expected
to be on-line by 1990. This alternative employs proven
technologies and is readily implementable.
2.
onsite Thermal Oxidation
Local residences are located as close as 400 feet upslope of the
site. Due to the relative location of residences, arsenic
emissions from an onsite incinerator are expected to require
reduction which would likely be accomplished only via
installation and operation of a forced flux condenser and
collision scrubber. Installation and testing of this equipment
,is 'ex~cted to take up'to six months. While emission control
efficiencies necessary to elimin~te unacceptable risk to
residents are expected to be achieved, these reduction
efficiencies cannot be confirmed'at this time. While more
complex than offsite incineration, the remaining components of
this alternative are implementable. .
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41
3.
Bnhanced Volatilization
. Several mobile enhanced volatilization systems are
available. However, the system most likely to be effective at
reducing both volatile and semi-volatile hydrocarbons from the
clay soil characteristic'of Greenwood Chemical has not been
equipped with air pollution controls expected to be necessary
in this case. Up to a year of construction and testing would
likely be necessary to install this equipment as needed. Bench
and pilot scale testing would also be necessary to confirm the
effectiveness of this alternative in meeting LDR and to refine
the design of the system. At this time, enhanced volatilization
has not been proven to be effective in reducing the, .
ccincentra~ions of semi-volatile compounds unique ,to this site.
Clay soils characteristic of~he site may present technical
problems, p~rticularly with redu~tion of semi-volatile compounds.
B.
Short-Term Bttectiveness
Short-term effectiveness addresses the period of time needed
to achieve protection of human health and the environment, and
any adverse impacts that may be posed during the construction and
operation period until cleanup goals are achieved.
1.
ottsite Thermal oxidation
. There would be minimal impact to the community during
implementation. Runoff shall be diverted away from ar~as .of
excavation as necessary. Air emissions would be limited to those,
generated during excavation. Risks posed by transport of the
contaminated soil have been determined to be minimal even in the
case of an accidental release in transport. Fugitive dust
emissions could be readily minimized using water sprays and
conventional engineering measures. Design of this alternative
could take less than a year, with all soil excavated and
transported tO'an offsite incinerator disposal facility within
one-half year provided that adequate capacity existed.
2.
onsite Tberaal Oxidation
The community residing in the immediate vicinity of the site
would be exposed to low-level arsenic emissions from an onsite
incinerator, particularly those residing upslope of the site.
While special air pollution equipment is expected to minimize
exposure to acceptable levels, delays may be incurred in getting
the system on-line and during operation. These delays would
result in additional contaminant releases to groundwater during
the period of concern. Design and contractor procurement could
exceed one year, while construction and imp~ementation could also
exceed one year. .
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42
3.
Enhanced Volatilization
While arsenic emissions from a low temperature enhanced
volatilization system could be lower than those from onsite
~hermal oxidation, special air pollution control equipment may
. still be required (forced flux condenser and high energy
scrubber). without effective air pollution-controls,
carcinogenic risk incurred by residents in the area may be up to .
lXlO-4. This equipment woulq have to be specially adapted to the
thermal treatment unit.- After adaptation, pilot scale testing
would be required to verify reduction efficiencies for arsenic
emissions have been met. This process could take up to 6 months.
In addition, bench and pilot scale tests would be necessary to
confirm that LDR requirements were being met and to refine design
parameters. Design could exceed one y~ar#- while construction and
implementation time could exceed two years.
F.
Long-Term Ettectivenes. and Permanence
Long-term effectiveness and permanence addresses the long-
term protection of human health and the environment once cleanup
goals have been achieved, and focuses on residual risk that will
remain after completion of the remedial action.
1.
oneite Thermal oxidation, otteite Thermal oxidation
These alternatives should be equally effective in the long
term. In each case, site-related organic contaminants are
permanently destroyed to the maximum extent possible under
current technology. If necessary, metals in solid residuals can
be immobilized via solification/stabilization prior to disposal.
A RCRA sub~itle C Landfill provides a disposal facility which
should further limit the migration of any inorganic contaminants.
remaining in the splid residuals.
2.
Enhanced Volatilization
- .
This alternative is expected to meet LDR requirements for
volatile organic contaminants. Reduction is not expected to be
as efficient for semi-volatile compounds. In either case, bench
and pilot scale studies will be necessary to confirm that LDR are
met after treatment. If necessary, stabilization/
solidification can reduce mobility of metals in the residuals
prior to disposal. 'Chemical residuals from the process would
undergo thermal oxidation in a RCRA-permitted incinerator. Semi-
volatileS" levels in solid residuals are expected to exceed that
found in residuals after incineration. These semi-volatiles
ultimately would have to be contained in the Sub-Title C
landfill. SOlidification/stabilization may help immobilize the
semi-volatiles prior to such disposal.
-------
43
-.
" .
G.
Cost
CERCLA requires selection of a cost-effective remedy (not
merely the lowest cost) that protects hUman healtij and the
environment and meets other requirements of the statute. . Project
cost includes all construction and operation and maintenance
costs incurred over the life of the project. An analysis of the
present worth value of these' costs has been completed for each
alternative described in this Record of Decision, and is provided
in section IX. Capital costs include those expenditures
necessary to implement a remedial action. Annual operating costs
are included in the present worth cost.
Enhanced Volatilization, Onsite Thermal oxidation, ottsite
Thermal oxidation
. Enhanced volatilization is expected to be the least costly
alternative to implement, assuming the volume of contaminated
soil is 4,500 cubic yards. However, the effectiveness of this
alternative would have to be demonstrated via bench and pilot-
scale treatability studies. Both onsite and offsite thermal
oxidation are proven to be effective. At a volume of 4,500 cubic
yards, the estimated cost of offsite thermal oxidation exceeds
the estimated cost of onsite thermal oxidation. The actual cost
of these alternatives may be relatively equal. Should final
volumes exceed current estimates, onsite incineration co~ld be
become relatively less"expensive than offsite. Enhanced
volatization is likely to be the least costly alternative at all
soil volumes above 4,500 cubic yards. "
H.
community Acceptance
A local citizens group (Concerned Citizens for Greenwood)
has strongly endorsed the selection of Off-site Thermal Oxidation
via written comments submitted in response to a Proposed Plan
released on August 24, 1989. Additional verbal comments by local
residents during a public meeting held on September 12, 1989 also
preferred this alternative. Co~ents during the meeting are"
summarized in the Responsiveness Summary in this document. In no
case did the community express preference for another
alternative. Concern was expressed regarding any alternative
resulting in the release of significant air emissions from the
site. "
I.
State Acceptance
The Commonwealth of Virginia has selected Off-Site Thermal
Oxidation as the preferred remedial alternative for the Greenwood
" Chemical site.
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44
IX.
TJlB SBLBCTBD REMEDY
Based upon consideration of the requirements of CERCIA and
SARA, the detailed analysis of the alternatives, and public
comments, the EPA has selected Off-Site Thermal Oxidation as the
Preferred Remedial Action for addressing Operable Unit One of the
Greenwood Chemical site. The Commonwealth of Virginia has
concurred in the selection. This remedy is protective of human'
health and the environment, is cost-effective, meets or exceeds
'ARAR's and utilizes treatment technology to the maximum extent
practicable.
The first primary objective of this remedy is excavation of
all soil within Operable Unit One exceeding site-specific, risk-
based cleanup levels. This volume is currently estimated at
4,500 cubic yards. .
.
The site-specific, risk-based clean-up levels are identified in
the Remedial Actiqn Objectives section of this document. Up6n
excavation of all such soils and subsequent removal from the
site, no soils within Operable Unit One (soils associated with
Lagoons 1,2 and 3 and Backfill North) shall present an
unacceptable risk to human health and the environment. In
particular, soils within Operable unit One shall no longer
present a risk due to direct contact (dermal contact or
incidental ingestion), nor will leachate migrating from these
soils result in an unacceptable risk to consumers of groundwater
receiving such leachate. To accomplish these objectives, all
soils exceeding levels identified in Table 11 shall be excavated.
In a4dition, soils with arsenic at concentrations of greater than
25 mg/kg shall be excavated.. . ..
Prior. to excavation of the contaminated soil of concern,
ditches, dikes, berms and/or other runoff/sediment controls shall
be implemented. The$e controls would be in compliance with'
Virginia's Erosion and Sediment Control Law and are expected to
minimize contact of runoff with OU-1 soil. Water collecting
within excavated areas of OU-1 shall be treated as F002 and F005
RCRA.listed waste (see below for rationale).
At this time, it is estimated that 4,500 cubic yards of soil
shall exceed site~specific, risk-based cleanup goals and thus
must be removed from the site. Soil sampling shall determine
when clean-up objectives have been met and excavation may cease.
Excavated soils woul~ then be staged and screened onsite in
compliance with RCRA regulations addressing waste piles (40 CFR
264.250-259). The screened soils shall then be transported to an
off-site thermal oxidation/disposal facility. Transport would be
in compliance with RCRA requirements applicable to transporters
of hazardous waste and Virginia Hazardous Waste Management
Regulations of July 1, 1988, which require that transporters of.
hazar~ous waste within Virgini~ possess a transporter permit
issued by the Virginia Department of Waste Management~
. .
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45
All excavated/transported soils shall then be thermally
oxidized, stabilized/solidified, and/or disposed in a RCRA
Subtitle C Landfill. Available site information indicates that
chlorobenzene and toluene have been used as solvent in chemical
production processes onsite (see page 6). These spent solvents
are categorized as RCRA-listed F002 and F005 wastes, respectively
and are contained in soils of OU-l. Per RCRA Land Disposal
Restrictions, and in particular, 40 CFR Section 268.41, this soil
may be disposed in a RCRA Sub-title C Landfill only after the
extract (see Subpart D, Appendix I) meets criteria identified in .
Table CCWE of 40 CFR 268.41.
Soils of OU-l also contain significant concentrations of
naphthalene, naphthalene derivatives, and numerous other semi-
volatile TIC compounds. Naphthalene contained in the soil is not
a RCRA listed waste. Therefore, LOR is not applicable with
regard to naphthalene. However, the soil containing naphthalene
is similar to RCRA-listed wastes KOOl and K081, which also
contain naphthalene and naphthalene derivativ~s. Therefore,
naphthalene treatment standards for KOOl and K087 in 40 CFR
Subpart 0 are relevant and appropriate. These standards are 8.0
mg/kg and 3.4 mg/kg naphthalene respectively. In each case, the
treatment technology used as a basis for developing the standards
was thermal oxidation (or incineration). Therefore, prior to
disposal, naphthalene concentrations should be reduced to 3.4
mg/kg (or the lower standard).
Thermal oxidation via incineration in a unit meeting RCRA
. Subpart 0 requirements will reduce organic contaminant
concentrations in the soil by 99.99\ 'and thus meet both
applicable and relevant and appropriate LOR requirements. - If
necessary, the soil should be stabilized/solidified prior to
disposal to meet RCRA characteristic waste criteria, particularly
the criteria for arsenic (5.0 mg/l EP toxicity).
Chemicals stored in onsite process buildings shall also be
incinerated/disposed offsite in .compliance with LDRs. Excavated
areas will be backfilled 'with clean fill, graded and revegetated.
At this point, soils within OU-l will no longer. present an .
unacceptable risk to human health and the environment. No
further maintenance of the area will be required to mitigate
risk. (Therefore, there are no operation and maintenance costs.)
At this point, a RCRA Clean Closure for the former RCRA units of
concern will be complete. (Groundwater remediation necessary to
complete RCRA Clean Closure will be selected under OU-2.)
The' major components and associated cos~s of the selected
remedy are summarized in Table 13, while ARAR's for the selected
rem~dy are summarized in Table 12.
-------
Table 12
.
u.""'~1ft
CI08UIII"8ft-Ir8CUIC .....
KTI08-.IC'UIC .....
LOCaI'l08-""'U'IC .....
C-J .Off-Slt. Ther-l OaldaUon .
and leU Subtlt I. C.
LandU 111!-vt
, .~ ~
,
'.
.'
.
'upedund A8end88nt. and
"autborhaUon An IlAMt
OSHA - lal.t, and "alth
.tandard. l' era 1'1' and It16
OSHA - a.c:ordlleeplnv.
"por~ 1"9. and a.lated
~laUon. 11 en n04
"--ree Con_nat 1- and
a.co..q act l8CaAt. lubtl....
C. 4. en 160
ItCM - Itandard. 'or OWner.
Operator. 0' '.~Itted
Ha..rdou. ...t. racilltl..
4. cra 164.1'-'64.'
ItCM - Cloeur. and 'o.t-Clo.ur.
40 era 164.110-1'4.111 acM - .
Manl'..tl"9. It.cordll_plnv and
a.portlnv. . 40 era U4: 10-J". 11
IICaA - Landfill.. 40 era 164.
S~rt HeM - Land Dhpo..1
~..trlctlon..41 era 1".
S~rt D "..rdou. and lolld
...t. A8end88nt. of It.4 1It..
A8end8ent. to acaat .~ tl-616.
r.deral La. 11;)101 .
It.nd.rd. Appllcabl. to
fr.n.port.r..of Ha.ardGu.
...t.-aCM Section 100) 40 cra
J6J-J61. 40 en IIO-llt.
..a Ad8lnI8t.red '.~t
'r09r..; Ibe H..ardou. ...t.
'.rait 'rOCJr.. -aCM SecUon 10
- O~ cra110.124 iteM -
Inclner.tor.. 40 era 26..
Subput 0
'RCRA -'Inclneralor.. .0 C~R
210.19
.llderne.. Act. ~o cra )~.I
'I.h .nd .lldll,. Coordination
Act. 40 era 6.102
CI.an air act IC..t - 'atlonal
18J..lon Standard. lor
".ardou. AJ r
'ollutant.. 40 cra 61.01
CI.an Air Act ICAAt - IIAAOS
40 cra I to It
It.t. 01 VI~lnla. a.,ulatlon.
lor the Control and Abat....t
01 Air follYtlon. aul.. 4-1, 4-
,16. ~-I. S-). S-4
Itat. 01 VI~lnla ".ardou.
.a.t. Mana....nt a.vulatlon..
~ul, I. 1'" .
Itat. of VI~lnla. 'ropo8ed
lolld .a.t. ""98-nt .
a.9Ulatlon.. ..rt II. Iubp.rt
C. ~ul, I. It.. *
acu. 40 cn 261
aCM. to cu 264
CI.an Air Act. .atlonal &.bl.nt
Air
Quallt, Standard.
S08A - Ma.I8Ya Contal...n..
.....1.
IMeL.t. 40 era 141.11-141.16
S08A - Ma.I8U8 Contal...nt
",v.1
eoal. IMerG.,. 4t cra I'I.~O-
"I'. ~I
P-
0\
CI.an .at.r Act IAAt - .at.r
Quallt, Crlt.rla
Vlr9lnl. Stat. ..t.r Control
La.. ISueface ..t.r and
Groundwat.r Quallt, Standard.'~
section 61.1, Chapt.r ).1 Code
01 Vlr91nla
* Promulgated Janua~y 9., 1989
-------
- 47
Table 13
CAPITAL & AWMUlL OPERATlwG -00$1 ESTIKATE SUMKAI'
ALTERMATfVt c.3: O"'SIT! THERKAL
OIIOATIOI8 AWO ICU l.AJ6O'fLLlwG
EST 1 KA TlO u.1T ~1
QUA.T I TT ~'ICt ('q~) ~E'!'E~C!S/~£w't(S
1 . 'iMIIAL ACTlOI8SI1ITI IIII""T ICII
1. CI..,I,. It'd G/'\MI,. 1.3 Acr.. ",OOO/Acr. 6,500 ..fel'lnC' 50. ::s
pe,. C1 .... idj-~:t-
2. TIII8IO"''''' ,~.., 0 I tdl", 1,000 I.' 15/\.' 5,000 ,.flr-lnC. 50. ::s
OJ It.. It'd ..,.. pe,. CT w.. adJ IoS: f(
3. T lII8I01' .,.., Stall,. A,... It'd S«Sf."e 2,500 IT 14/1T 10,000 ..f.r-InC. 50
Cane,.ot
4. Oecane_lr\8tlan 'eeility \..1. 10,000
5. Ad8f"fltr-.clwe end M..lt~ , Safety 2 IIOfIC~' S4 , ooo/tlo. 8.000
Trell.r.
... T O'T A&. 39, 500
II. CQlTMtlllATtD SOl\. TIUT".T
1. lac..,.e f an, Irocludf1'4 CI88ft Sol t 5,000 T- 150/Tan 250,000 . ..f8".,.c~~. :c,~
COWl" I" 1...-. I end So per C1 w'~idlIoS:t':
2. Tr..portatlan COlt (to 1ft 1',. 4,500 T- sn5/Ton 1,012,500 ..fer-lnC. 62
"'-0Wd Ol~t 'eeillty)
3. Off'Site T~e,..t OXidaclon It'd 4,000 Tona S1, ZOOITon 5,400,000 ..f.,.InC. ':'':'. .ai.S':
\.It'dfIUI,. r.f.r to tootno:~ .
"~i. C.
4. Oecont_lr\8cfan It'd Ol~l of 1..1. 200, 000
.en..
5. lleell, 18Mtf..t. Tr....,.t Off.llt. - I..'. ~.OOO
OlapDlat of ~I~t.
"TaT AL ',947,000
It I. ~TIIG ACTIVITI..
1. So IL s...ptt... IN ANt yel. for 50 08Y8 12 . 000/11.., 100,000 'ef8"Ine. "3
Soil Corte.'Nc'an 180ft' tor'"
2. Irw'''~,& ""'U... IN StUd'. L.S. 150,000 ..f8"Ine. 44
3. IOH S...t t... IN ANt.,.t, fer L.S. 50,000
lecklrOllld I80ftI cor1... ,
4. AddUtONt ~ '8cH Itf. 50 08Y8 saso,. .- 42.500 ..f'''Ine. 6it
fw 'roc...'" .. LlftftU
Qpef'8t f -
"TaTAL 362.500
,-
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48
CAPITAL &. ANNUAL OPERATING COST !ST!KAT! ~.T.
ALTERMAT!Y! C.]: O,F'SITI THERKAL
OXIDATIOM AMe) leu LAMO'ILLIIIG
UflKATED UMI T COST
QUA..T t TY "IC!. (1~) '!'!'ENCf$I'£~A'(S
IV. II TI CLaIUIl
,. '~Ulll and '..reell"" 4,500 CT szo"T 90,000 ..ftrtrlCe 50
l. Ifte '"toretlon 1.3 Acre U,Ooa/Acre 3.900 .eftrtrlCt 50
SUlTOTAL 91.900
TOTAL OI'ICT COlT 1.4U,9OO
V. IIIIIIICT COlT
"eel tll .... "'ety . 10'1 . 101,000
II d , Icooe Cont I "'I8f'C'Y . '" 1.113.000
Pe,..lttl"" and L8t8l . 51 . 50,000
E,.. i Ner f "" 8t'CI 0" I 1ft a 10'1 . 101.000
TOTAL IIIIIIICT COlT 1.365.000
TOTA&. WITA&. COlT . 1.787.900
..
VI. ~oue 0
VII. TOTAL "IIIIIT WOIT. 1.7'81,900
Noee: .. COlt pert.ine eo on-.ite ICtfvltt" only. ".010.400
>:ote:
See Focused Feasibil:ty Study for Ref~rpnces
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49
XII. STATUTORY DETERMINATIONS
The selected remedy meets statutory requirements of CERCLA
and the NCP. The remedy is protective of human health and the
environment, complies with applicable or relevant and appropriate
requirements, utilizes permanent solutions to the maximum extent
practicable, is cost effective, and satisfies the statutory
preference for treatment which permanently and significantly
reduces the volume, toxicity or mobility of hazardous substances
as a principal element. .
Protection of Human Health and the Environment
The selected remedy will provide protection via excavation
and removal of all soils exceeding site-specific health-based
levels. Removal of the soils of concern will reduce potential
carcinogenic risk presented by the soils to within the 10-4 to
10-7 range, while hazard indices for non-carcinogens will be
reduced to less than one. Conventional engineering controls will
prevent any short-term risks during excavation.
Compliance with Applicable or Relevant and Appropriate
Requirements (ARAR's)
The selected remedy will comply with all ARARs of concern.
By removing soils which exceed health-based clean-up levels,
contaminant loading to groundwater will be ieduced to a point
where MCLls, WQC, or health based criteria are achieved. . Since
the excavated soil will contain RCRA listed wastes F002 and F005,
applicable or relevant and appropriate RCRA LDRs will be met
prior. to disposal. Removal of all soil exceedil'~g health-based
levels will meet RCRA Clean Closure requirements for Lagoons 1,2
and 3 and Backfill North upon implementation of a groundwater
remedy (part of OU-2). ' See section X, Selected Remedy, and Table
13 for a more detailed discussion of ARARls.
Cost Effectivenes8
The selected remedy affords overall effectiveness
proportionate to its costs. While enhanced volatilization is
expected to be less costly, reduction of semi-volatiles to
criteria of concern cannot be confirmed at this time. While the
estimated cost of Onsite Thermal Oxidation is less than the
estimated cost of' Offsite Thermal oxidation, the actual cost of
these alternatives may be relatively equal. 9nsite, Thermal
Oxidation do~s not provide the short-term effectiveness (see
below) of the selected remedy and is not as implementable.
utilization ot Permanent Solutions and Alternative Treatment (or
Resource Recovery) Technoloqies to the Maximum Extent Practicable
. The selected remedy provides the best balance oftradeoffs .
among the alternatives with respect to the' evaluation 'criteria,' '"
particularly the five primary balancing criteria. In addition,
-
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50
technologies to the maximum extent practicable.
Offsite Thermal oxidation and Onsite Thermal Oxidation are
equally effective in the long-term and are both permanent
remedies. Enhanced volatilization is not known to be as
effective in the long-term, particularly wit~ regard to "reduction
efficiency for semi-volatile prganics.. Should significant
concentrations of semi-volatiles remain in residuals after
Enhanced Volatilization, this alternative would not be as
permanent. Similarly, while Offsite and Onsite Thermal Oxidation
reduce the toxicity, mobility or volume of organic contaminants
to the ma~imum extent possible, Enhanced Volatilization may not
reduce semi-volatiles to the same extent.
Offsite Incineration is the most readily implementable
alternative. While incinerator capacity does not meet demand at
this time, capacity should be adequate at the time of the
Remedial Action. Onsite Thermal Oxidation is implementable.
However, special pollution controls (a forced flux condenser and
high energy collision scubber) would likely be installed to
minimize arsenic emissions and resultant risk. These controls
are not available on mobile incinerators at this time and would
have to be installed on such a unit as part of this remedy.
Design, installation and testing of these controls will likely
result in a longer implementation time than that for Offsi~e
Thermal Oxidation. In addition, continuous monitoring would be
necessary during Onsite Thermal Oxidation ~o confirm
effectiveness of arsenic emission controls. Due to the expected
longer implementation time, Onsite Thermal Oxidation would not be
as effective in the' short term. Similarly, Enhanced
Volatilization is expected to require similar air emission .~
. controls.' Associated emission control tests would supplement'
bench and pilot-scale tests necessary to confirm the' .
effectiveness and design of Enhanced Volatilization. In any case,
risk to residents from air emissions generated at an offsite
thermal oxidation facility ar~ expected to be insignificant.
Overall, Offsite Thermal Oxidation is the selected remedy
due to its implementability and short-term effectiveness.' Design
and construction ot special air pollution controls will be
unnecessary and associated potential delays avoided. Operational
problems relating to control of emissions with this equipment
will be eliminated as well as resultant carcinogenic risk to
residents in the vicinity of the site.
The community surrounding the site strongly favors t~
selection of an offsite treatment alternative. The community has
expressed concern regarding exposure to emissions from an onsite
treatment unit. The community also favors performance of the
remedy as soon as possible. As discussed previously, delays may
be incurred during the design and implementation of both onsite
treatment remedies. Based on the above considerations, EPA has
selected Off-Site Thermal Oxidation as the remedy. The
Commonwealth of Virginia concurs in this sele~tion.
-------
. 51
Preference for Treatment as a Prin~ipal Blement
The selection of Offsite Thermal Oxidation satisfies the
statutory preference for treatment which permanently and
significantly r~Quces the volume, toxicity or mobility of
hazardous substances as a principal element of the remedy.
-------
Appendix
GREENWOOD CHEMICAL SITE
ALBEMARLE COUNTY. VIRGINIA
OPERABLE UNIT ONE
RB8POlf8IVDlB88 St1XXARY
This Responsiveness Summary is intended to document public
concerns and comments expressed during the public comment period
regarding Greenwood Chemical Site Operabl. unit One (OU-l).
The summary also documents EPA's responses to the comments and
concerns that were received. Information is organized as
follows:
1.0
overview
2.0
Summary of Comments and Responses
3.0
Remaining Concerns
Attachment:
List of Community Relations Activities
Conducted at the Greenwood Chemical Site
1.0
OVERVIEW
sup~rfund Remedial Actions associated with" cleanup of the
Greenwood Chemical Site"will be conducted in stages known as
Operable Units (OUs). EPA recently completed and released a
Focused Feasibility Study (FFS) and a Proposed Plan for OU-1
which addresses contamlnated soil associated with four former
lagoon locations and a backfill area, and drums/containers of
chemicals remaining in onsite buildings.
A public comment period on the FFS and Proposed Plan for OU-l.
began on August 24, 1989, and at the request of the local
citizens' group, extended until October 24, 1989. The comment
" period, as well as .the local availability of copies of the FFS
. and proposed Plan, were announced to the community-of-concern in
the Charlottesville Dailv proaress on the first day of the
public comment period.. The announcement also provided
information about a public meeting .eo discuss these documents.
" The meetinq, held on September 12, 1989, was attended by
approximately 40 people. .
-1-
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2'.0
SUMMARY OF COMMENTS AND RESPONSES
. .
GENERAL OBJECTIVE AND CLARIFICATION C£" OPERABLE UNIT 1 (OU-l)
2.
1.
. .
In refere~c8 to the Proposed Plan., what. area is involved
when the term "onsite" is used?
" "
B'A .e.pon.ez (Spoke,man reterred to a large disPl~y map
while answering the qu..tion.) "Onsite" reters to the area
of the facility property or approximately five acres.
EPA isproposinq to spend about $8 .illion on the cleanup
ot OU-l. What is EPA planning to do to protect the
interests ot people vho ~on't live close to the site? Is
the Agency going to spend that money to make a five-acre
plot habitable or spend the money to protect all of the
people living in surrounding areas?
.'A .e.pon.ez EPA policy is to render the qroundwater both
under and around the'site drinkable. The 1.5 acres of
OU-l comprise the portio~ of the site with the highest
levels ot soil contamination. Addre..ing this area vill
eliminate a major groundwater contaminant source. It the
source is eliminated, additional contaminants can no longer
migrate into the groundwater. Consequently, though EPA may
spend money on actions thatvill occur in the relatively
small area ot OU-l, the.. actions should benetit the entire
surrounding area." '
EPA vill pertor. additional groundwater monitoring
following implementation of the proposed remedial action to
determine th, impa~t otcontaminated soil removals. It is
possible that a pocket ot contaminated groundwater could
remain atter soil removal. It thi~ is the case, EPA will
undertake a r..edy, such as pumping the contaminatea
,groundwater out ot the ground and treating it. A aecision
regardinq groundwater vill be .ade in the tOllow-up
" activities that EPA expects to conclude in about a year.
TYPE OP OONTAM7NATIOM AND EXTENT OP MIGRATION
1.
"Are the pri.ary soil ,contaminants volatile organics or
metal.?
.,a ...poD.e. Volatile and s..i-volatile organics are
generally a concern in case. ot groundwater ~ontamination.
At this .it., the orqanic. in the soil are migrating to the
groundwater and constitute a primary groundwater problem.
Metals in the soil pre.ent a probl.. via direct contact.
-2-
-------
3 .
4 .
" Due to'the,h~gh clay ~ontent of the soils, the metals are
not migrating in~o groundwater to a sig~ificant extent.
Elevated metals are not appearing in groundwater at this
time. Also, the soil contamination is iocalized.in the'
area'ot the tormer facility and elevated concentrations ,of
site-related metals have 'not been detected in offsite
solIs. .
2.
Do contaminants in the groundwater become less concentrated
with distance trom the s~te?
BPA a..pon..a As expected, concentrations ot site-related
contaminants decline with distance trom the primary sources
ot contamination. For in.tance, a aonitoring well onsite
has high levels ot contamination, but those levels decrease
significantly at a point 500 teet downgradient at the
well. Contaminants have not been detected in residential
wells downgradient at the site (approximately 2,000 feet
away). This is the dilution ettect. Groundwater flow from
the mountain behind the site helps dilute contaminant
concentrations.
Does EPA maintain any downgradient monitoring wells oft
site?
ZPA a..pon..z The monitoring well tarthest downgradient of
OU-l is about 500 tee~ southeast at Lagoon 5." At that
point, contaminant levels are low enough that the
groundwater is almost drinkable. There are no monitoring
wells downgradient ot this point. However, there ,are
downgradient residential w~lls that may be s~mpled
periodically a8 part at EPA's ongoing activities. .
How tar has contamination spread?
BPA ,R..pon..'. A monitoring well located 500 feet southeast
ot Lagoon 5 contained detectable concentrations of some
contaainants, but at a well about a h~lt mile downgradient
ot the site, no contaminants have been detected.
Therefor., contaminants have migrated to a point between
500 t.et and one-halt mile tram the site.
EPA has installed about 25 monitoring wells. , Additional
wells might help turther detine the contaminant'plume, but
EPA may determ'ine the extent ot contaminant migration by
using groundwater modeling. Modeling uses available
information about the site to predict how far contamination
will migrate. .
-3-
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5.
rrom May through July 1989, Albemarle County-had the
highest- rainfall ever recorded for this area. The qround
was saturated, and there was a lot of runoff. Do
conditions like this increase the spread of contamination?
.~A ...poD.el There are various theories regarding. this
question. When the water table is low, there is less water
avaLlable to dilute-contamination. When there is-
significant precipitation, there i. aore opportunity for
so~l contaminants to.migrat. to qroundwat.r. .
(Th. speaker sugg..ted that EPA should r..ample residential
well. soon. )
FINANCIAL LIABILITY ASSOCIATED WITH CLEANUP
1.
2.
What does the term "responsible party" mean?
liability for cleanup costs?
.~A ...pOD..1 Responsibleparti.s (RPs) are all those who
have be.n determined to be at least partially responsible
for the contamination of a sit.. Th.se parties may include
past and present owners, generator. and transporters of the
hazardous substances ot concern. EPA has identified some
potentially RPs associated with this site, but additional
potentially RPs may still be confirmed.
Does it imply
Routinely, under Superfund, .those responsible for creati~g
a problem are qiven the opportunity to take corrective.
actions. If they decline to do so, EPA undertakes the
action using Superfund money. . RPs are held liable. for any
~leanup costs incurred by EPA, however, and EPA wil~ take
legal action to recover those funds.
What are the State's financial responsibilities for this
type ot cleanup action?
. . .'
.~A ...poD.e. Th. State is responsible for 10 per~ent ,of
all cleanup co.t., under Superfund.
SITE-RELATBD RISKS ASSOCIATED WITH THE SITE
1.
If lO,OOOpeopla spent their lives drinking the qroundwater
under tha sita, how many ot them could expect to get
cancer? ,
. .~A ...pOD... An estimated one in 10,000 people consuming
onsita qroundwater may contract cancar according to a
Bas.line Risk A~se8sm.nt performed by EPA.
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2.
Could water fowl that stop at the site spread contamination
to other areas nearby? .
BPA ...pOD..: This is a remote possibility. EPA's concern
is not that animals using the site might spread
contamination. Rather, the Agency's concern is for the
ettect ot the site on the .health ot the animals.
3.
What risks would be associated with' airborne contaminants
released during soil excavation and transpottation
activities? .
BPA ...pOD.., The short-term ettects of remedial
activities are a primary concern ot EPA, and airborne
particles will b. taken into account during remedial
design. There are various methods available to control air
transport ot contaminants, and every eftort will be made to
do so. The specitic method will be selected during the
desiqn phase. .
AVENUES FOR PUBLIC PARTICIPATION
1.
2.
Who is presenting Greenwood's case to those who will decide
which sites get tunding to proceed with remedial actions?
Who is the community's advocate with EPA?
BPA ...pOD.., Several people, including the Remedial
Project Manager, work together to present Greenwood's case
toEPA Headquarters. The State is also involved in this
ettort because ot its responsibilities under Superfund.
However, the public comment period is an excellent
. opportunity tor the co~munity to join the effort to draw
. attention to its needs and concerns regarding"this site.
The Community Relations Coordinator (CRC) for the site is
the primary contact tor the public within the Agency.
Whenever questions or concerns arise, interested parties
may contact their CRC, the eRC will bring their concerns to
the attention ot the appropriate people.
Should community members attempt to enlist the help of
their Congre.smen to qet tunding?' .
BPA ...pon.., The; time to contact your Congressman is when
the Superfund Bill is proposed tor reauthorization.
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. .
REMEDIAL ALTnNATIVES FOR OU-l
2.
J.
1.
It EPA selected Alternative C-l,. No Action, what would
happen? Would groundwater downstream become increasingly
contaminated?
BPA .e.poD.eJ It no a~tion is taken, soil contamination
will continue to migrate to groundwater.
However, it is not necessarily true that downgradient
groundwa~.r will become increasingly contaminated. EPA
does not have reliable, historical groundwater data for
this site. All of EPA's data has been obtafned over the
last tew years, since the Agency's remedial investigations
began. There is no information available to indicate what
groundwater quality was like during the facility's peak
. operating years in the 1970s. Therefore, it's impossible
to say whether contamination levels are increasing or
decreasing. It is likely, though, that groundwater
contaminant levels are decreasing because the facility is.
no longer operating and discharging wastewater into the
lagoons. This means the contaminant source is no longer
being replenished.
The preterred alternative, Alternative C-J, is offsite
incineration. Where is the incinerator located, and will
EPA use the nearby railroad as a means of transporting
excavated soils off site? Transportation costs are a
considerable portion of the remedial expense, and money is
a valid concern.
BPA .e.poD.e, The specific incinerator that will be used
has not been identified, yet. The facility will be
determined during the design phase. Incineration..
facilities will be given an opportunity to bid to provide
the necessary goods and services.
Costs are important. Transportation costs are a major
consideration, and rail transport could be built into the
. remedy, it it i. found to be the best choice. . EPA will
certainly keep the railroad's proximity to the site in
mind.
Doe. the 16-month period of pertormance associated with the
preferred alternative for OU-l include the desiqn phase, or
does itbeqln when the.ansite work begins?
BPA ...pOD..' Assuming funds are available, the period ot
pertormance begins when the Record ot Decision is siqned.
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4.
5.
6.
7.
-- --
I
Do the. Operable Units proceed concurrently?
IPA a..poD..S They do. Within a year, EPA expects to have
another Proposed Plan that will address the rest of the
site. .
What "pressure" is EPA bowinq to by moving rapidly on just
one of the operable units identified at the site? Will
completinq cleanup actions for OU-l remove the majority of
site-related risks?
IPA a..poD..' Cleaninq up OU-l will address a principal
'threat at the site, and EPA has sufficient documentation to
support the decision to take action at this time. There is
no reason to wait. .
The community is applying for a Technical Assistance Grant
(TAG), but hasn't received ~ne at this point: so, no'
consultant has been hired to review EPA reports. Yet, EPA
has taken this "extra" action (OU-l). Is a response still
required by October 24, 1989? .
B'A ...pOD..' Yes, a response is required by the close of
the comment period. There is no way of knowing when the
community will receive TAG money.
When will EPA know if funding is available to implement .the
Proposed Plan for OU-l? Ca'n you predict ~ like~,y schedule
,for receiving funds?
. . . .
. IPA a..pOD..,' It's'very difficult '~o say whEan funds will.
be available for Greenwood. There is a sum of money
available for this type of action, but there are many sites
acrosa tha country vying for attention. The comment period
is a good ti.a for the public to attempt to influence
fundinq decisions. Because more sites may be ready for
cleanup than there. is money available to fund the work,
environaantal prioritization of sites will be necessary for
the upcoainq fiscal years until Superfund is reauthorized.
When tha remedial design for this site is 90 percent
complated, the site will be prioritized. That will
deteraine whether funds to proceed will be made available.
If the site is below the fundinq line, it will become part
of tha "queue" of waitiag site.. If a site remains in the
queue for a year, it automatically receives more priority
point.. So,' it i. unlikely a sita will remain in the queue
for two years in a row. Unfortunately, there is no good'
way to estimate when the site will be acted on. Reqion III
will simply continue to' move forward on this site.
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ot co~rse, it the RPe agree to undertak. the cleanup
action, prioritizati~n will not be a. tactor,and the
cleanup will proceed as soon as possible. .
COMMENTS IN SUPPORT OF THE PREFERRED ALTERNATIVE
1.
2. .
J.
3.0
A resident stated that EPA'. preterred alternative appears
to be the "most advantageous" alt.rnative tor the local
community arid tor allot Albemarl. County. The speaker
also said that this choice is "tar .uperior" to the other
options under consideration. .
Another resident stated that, although people .have
expressed concern about remedial costs versus the level of
risk associated with the site, it should be rememberea that
the community has an ethical responsibility to its
children, and to all those who are yet to come, to see that
this site is cleaned up. This speaker said that this
matter is not about a specific five-acre plot ot land but,
rather, should be viewed as a global concern. He applauded
Supertund and the EPA tor developinq this kind ot proqram.
One written comment was received durinq the public comment
period. The letter was trom the president ot the Greenwood.
Citizens' Council who stated that the group is
overwhelmingly in tavor ot EPA's preterred alternative,
Alternative C-3. This writer urged EPA to expedite the
des.fgn and remediation ot OU-1, while also tast-tracking
the remainder ot the remedial investigation.
REMAINING CONCERNS
Although the community is. in agreement with EPA's Proposed Plan,
twq areas ot concern not c~vered by the plan remain.
1.
2.
The .tatus ot onsite buildings is a concern.
contaainated, and will they be removed?
..& ...pOD..s That is undetermined at this time. The
build!nq8 will be addressed in the ongoing study, and.a
decision should be reached within a year.
Are they
It was suggested that downgradient residential wells should
be resampled soon to allay concerns about contaminant
migration. that may have occurred during unusually heavy
summer rains. .
..& ...pOD..'
continue.
Periodic otfsite monitoring is expected to
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