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Greenwood Chemical Site Record Of Decision For OU-2 15
Alternative GW-3 and Alternative GW-4 both employ a combination
of Air Stripping and Carbon Adsorption to treat organic con-
taminants. Both technologies have proven to be effective in
removing many of the organic compounds of concern. In addition,
these technologies will likely remove those organic compounds for
which treatment information is unavailable. Design parameters
for treating .the organic compounds of concern would be developed
through trea£ability studies. Organic compounds removed during
treatment would accumulate in carbon filters, which would require
periodic disposal or replacement.
Alternative GW-2 employs UV/oxidation for the treatment of
organic compounds. This technology has proven effective in
treating many of the compounds of concern. In addition, it is
likely UV/oxidation will effectively treat those compounds for
which information is unavailable. Design parameters for treating
the organic compounds of concern would be developed during
treatability studies. Since UV/oxidation would destroy organic
compounds, no disposal of organic treatment residuals would be
necessary.
Alternatives GW-2 and GW-4 remove metals through the same series
of primary treatment steps - precipitation, sedimentation and
filtration. This treatment process has proven effective in
treating the majority of metals. Alternative GW-3 employs a
combination of filtration and ion-exchange for metals treatment.
In the case of all three treatment alternatives, inorganic
residuals are generated.
Regarding cyanide treatment. Alternatives GW-3 and GW-4 both
utilize alkaline chlorination for treatment of cyanide, while
under GW-2, UV/oxidation is expected to reduce cyanide as needed.
In both cases, cyanide would be destroyed through the treatment.
In either case, the effectiveness of these technologies would be
confirmed through treatability studies.
SHORT TERM EPPECTIVEHE88
Risks to workers, the community and the environment during
implementation is expected to be minimal in the case of all three
action alternatives*
Alternatives GW-3 and GW-4 include air stripping. In each case,
volatile organic air emissions would be controlled with a carbon,
vapor phase adsorption unit and there should be no resultant risk
.from air exposure to the community. Carbon within this unit
would have to replaced periodically to maintain effectiveness of
emission control. No air emission controls for volatile organics
are expected to be necessary with Alternative GW-2.
In the case of each alternative, compliance with treatment
discharge ARARs identified above should assure protection of
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Greenwood Chemical Site Record Of Decision For OU-2 16
Stockton Creek and its tributary (West Stream).
IMPLEMENTABILITY
Alternatives GW-2, GW-3 and GW-4 are all readily implementable.
Moreover, all three of these alternatives could be implemented
within one and a half years of the start of the design. The
technologies associated with each alternative have been success-
fully implemented under similar circumstances.
COST
The estimated present worth, capital cost and operation/ main-
tenance cost varies within a range of five percent from one
alternative to the next. The estimated present worth of Alterna-
tive GW-2 is $3,218,000, while the estimated present worths of
Alternatives GW-3 and GW-4 are $3,34?,000 and $3,190,000 respec-
tively. As a result, the cost of the alternatives may be con-
sidered relatively equal. In each case, benefits gained from the
action of concern are expected to be proportional to the costs
incurred.
STATE ACCEPTANCE
The Commonwealth of Virginia has expressed a preference for
Alternative GW-2 - Precipitation and UV/Oxidation.
COMMUNITY ACCEPTANCE
Comments received from the local community reflect a preference
for the Alternative GW-2 provided that the water treatment system
is proven to be effective prior to full-scale implementation.
SELECTED REMEDY
Section 121 of CERCLA38 and Section 300.430(e) of the NCP3^ es-
tablish a variety of requirements relating to the selection of
remedial actions. Comparing the reviewed alternatives with those
requirements shows that the best remedy for remediating con-
taminated ground water and lagoon water at the Greenwood Chemical
Site is Alternative GW-2: Precipitation and UV/Oxidation. The
estimated present cost of this remedy is $3,218,000. Based on
current information, this alternative provides the best balance
of trade-offs among the alternatives with respect to the nine
42 U.S.C. § 9621.
37 40 C.F.R. § 300.430(«>.
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Greenwood Chemical Site Record Of Decision For OU-2 17
criteria that EPA uses to evaluate each alternative.
The selected action consists of two major components: l) extrac-
tion of contaminated ground water and lagoon water and 2) treat-
ment of the water prior to discharge.
Data collected during the RI shows that because the hydrogeology
of the Site is complex it is not possible to optimize the design
of the ground water extraction system with available hydro-
geologic information. Therefore the installation of the extrac-
tion well network will be staged. Upon the evaluation of data
generated during each phase of the ground water extraction, the
extraction system will be modified as necessary to optimize both
the reduction of the toxicity, mobility and volume of ground
water contaminants and to minimize contaminant migration.
To estimate the present cost of the selected remedy, the FFS has
projected a potential extraction system based on available
hydrogeologic information data in the RI report. The projected
system includes an estimated seven (7) extraction wells. EPA has
assumed that five existing monitoring wells can be used for
extraction, therefore two (2) additional monitoring wells will
need to be installed. This is only an estimate; additional
extraction wells will be installed under this action if neces-
sary. A submersible pump will be installed in each extraction
well. In addition, three (3) piezometers are planned to be
placed around each well to monitor water levels. Withdrawn
ground water shall than be conveyed to an onsite water treatment
facility through a subsurface pipeline network. Water from
Lagoons 4 and 5 will be conveyed to the facility in a similar
manner. The system will generate an estimated average of 35
gallons per minute of water, based on a review of hydrogeologic
data in the RI report. The treatment facility is projected to be
located approximately 500 feet from a tributary of Stockton Creek
(West Stream). The treated ground water shall be discharged to
this stream after treatment. The lagoon water may be returned to
the lagoons after treatment if this is determined to be ap-
propriate.
The specific nature of the initial extraction system shall be
determined during the Remedial Design. Subsequent modifications
shall be based on the review of data generated during initial
operations. Extraction parameters to be determined include well
location, depth of withdrawal and pumping rate. All ground water
parameters of concern shall be monitored frequently before and
during system operation. Continual evaluation of monitoring data
'will ensure that hydraulic control of both contaminated ground
water and hydraulically-connected, uncontaminated ground water is
maintained. All collected data shall be evaluated to determine
the final remedial action goals for ground water. A detailed
plan for developing these goals will be developed during the
Remedial Design.
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Greenwood Chemical Site Record Of Decision For OU-2 13
A projected ground water sampling plan has been outlined in the
FFS for cost estimation purposes. The actual nature of the
ground water monitoring plan shall be determined in the Remedial
Design, but shall consist of, at a minimum, the following elem-
ents: monthly monitoring of the seven extraction wells and seven
existing monitoring wells for the first six months, after which
time it is assumed that the extraction wells will be sampled on a
bimonthly basis and the monitoring wells sampled on a quarterly
basis. In addition, the monitoring plan shall include periodic
sampling of residential wells determined to be within the im-
mediate migration pathway of ground water contaminants and sam-
pling of existing monitoring wells to help define the extent of
ground water contamination. Additional monitoring wells will be
installed and sampled as deemed necessary to further define the
extent of contamination. At this time, it is assumed that the
extraction system and associated monitoring under this interim
action will run for no more than five years, at which time a
final action for ground water will be selected and implemented.
The treatment facility shall consist of a series of water treat-
ment units to remove inorganic and organic substances from the
plant influent. The primary objective of the water treatment is
to reduce contaminant levels in the facility effluent to NPDES
requirements developed pursuant to Virginia Water Control Act and
the federal Clean Water Act prior to discharge to a tributary of
Stockton Creek (West Stream). NPDES requirements will include 7-
day static renewal bioassay tests using Ceriodaphnia and Pime-
phales promelas, conducted in such a manner and at sufficient
dilutions to determine the "No Observed Effect Concentration" and
corresponding Chronic Toxic Units for survival and reproduction
or growth, and a 48-hour LC 50 and corresponding Acute Toxic
Units (or a similar bioassay test). Since the effluent shall be
discharged onsite, the administrative requirements associated
with an NPOES permit need not be met. However, all applicable or
relevant and appropriate substantive NPDES and VPDES require-
ments will be met3*.
To meet the substantive NPDES requirements of concern, removal of
both inorganic and organic substances will be required prior to
effluent discharge. The precipitation system will be designed to
remove inorganics to levels which meet NPDES-based effluent
standards. Reduction of inorganics is also necessary to optimize
the organic reduction efficiency of the UV/oxidation process.
The specific treatment steps necessary to reduce inorganic
concentrations will be developed and refined during treatability
studies and as part of the Remedial Design. To help estimate the
cost of inorganic treatment, the FS has projected the treatment
steps expected to be used.
The first projected step in the inorganic treatment process is
the precipitation of iron through the addition of chlorine and
42 U.S.C. 9621(e).
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Greenwood Chemical Site Record Of Decision For OU-2 . .19
lime. Trimercapto-S-triazine could be added with the lime to
precipitate dissolved mercury if necessary. Precipitated metal
hydroxides and mercury would accumulate as a sludge within a
settling tank. Appropriate measures would be taken to prevent
the emission of volatile organics during this process. For
example, the settling tank may have a closed hood. Final removal
of suspended solids would occur in a closed tank containing a
multimedia filter.
Sludge and filtrate generated during the precipitation process
shall be handled in accordance with treatment, storage, disposal
and transport regulations under the Resource Conservation and
Recovery Act.3" The sludge will be generated through the treat-
ment of water containing RCRA listed waste (F001-F005) and will
therefore be disposed in a RCRA Subtitle C landfill. Should the
sludge not meet applicable RCRA Land Disposal Restrictions,
treatment to meet the criteria of concern will be required prior
to disposal in a RCRA Subtitle C landfill.
The pretreated water shall then undergo treatment by UV/oxidation
to reduce organic concentrations as necessary to meet substantive
NPDES permit requirements. The water shall be directed to a
reactor where either ozone and/or hydrogen peroxide is injected.
Ultraviolet light is added to this process to further increase
the oxidation potential of the system. The UV/oxidation process
will be designed to destroy organic compounds to the level
necessary to meet NPOES requirements. No organic residuals
should be generated by this process. Treatability studies shall
be conducted to confirm the effectiveness of the UV/oxidation
system and to refine design parameters as necessary.
Should ozone be used in the UV/oxidation process, any residual
ozone from the system should be reduced as necessary to meet
requirements under the federal Clean Air Act.*' Since UV/oxida-
tion destroys organic compounds, no significant air emissions of
organic compounds are expected from this process. As a result,
controls to meet National Emission Standards for Hazardous Air
Pollutants (NESHAPs) under the federal Clean Air Act are not
expected (but can be implemented if necessary).
Should treatability or pilot-scale studies determine that UV/oxi-
dation is ineffective in meeting NPDES requirements for organic
compoundst treatability and pilot scale studies for technologies
under Alternatives GW-3 or GW-4 will be conducted to confirm
their effectiveness. These technologies may then be implemented
if necessary through either an Explanation of Significant Dif-
ferences or an amendment to this ROD, as appropriate.
As noted earlier, Alternative GW-2 calls for the design and
4ff C.F.R. §§ 262 & 268 (1990).
40 The NAAQS for ozone is 235 M/m3. 40 C.F.R. § 50.9.
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Greenwood Chemical Site Record Of Decision For OU-2 20
implementation of an interim remedial action to protect human
health and the environment. The goals of this remedial action
are (1) to initiate reduction of ground water contaminant toxic-
ity, mobility and volume, (2) minimize the migration of ground
water contaminants (3) collect data on aquifer and contaminant
response to remediation measures, and (4) eliminate unacceptable
environmental risks posed by water in Lagoons 4 and 5. The
ultimate goat of remediation will be met through a final ROD for
ground water at the site, which shall be prepared after evaluat-
ing data generated during the interim action. After the period
of time necessary, in EPA's judgement, to arrive at a final
decision for ground water at the site, a final ROD for ground
water, which specifies the ultimate goal, remedy and anticipated
remediation timeframe, will be prepared. The extraction system
installed under the interim action may be a be a major component
of the remedy selected in the final ROD for the Site. The
interim action shall be implemented until the final ROD for
ground water is issued. Should the final ROD select continued
extraction and treatment as the final- remedial action for ground
water, the system installed under the interim action will con-
tinue operating if necessary (and technically feasible) while any
system modifications selected by the final ROD are implemented.
A final remedial action for ground water shall be selected
through the ROD process as soon as the data necessary to make
such a decsion is available.
STATUTORY DETERMINATIONS
Alternative GW-2 would achieve substantial reduction in risks by
initiating the reduction of the toxicity, mobility and volume of
ground water contaminants, by limiting ground water contaminant
migration and by reducing environmental risks associated with
contaminated lagoon water.
The selected remedy meets those applicable or relevant and
appropriate requirements specific to this action. This action
shall be consistent with ARARs addressing discharge of treated
water under the federal Clean Water Act and the Virginia Water
Quality Control Act, handling of hazardous wastes under RCRA, and
control of air emissions under the federal Clean Air Act and
Virginia's Regulations for Control and Abatement of Air Pollu-
tion. A final remedial action for ground water at the Site shall
be selected in a followup ROD to be issued in an estimated five
years.
,The selected remedy is protective of human health and the en-
vironment, in accordance with its interim nature. The overall
effectiveness of this remedy is proportional to the projected
costs and provides the best balance of trade-offs among the
alternatives with respect to the evaluation criteria. The local
community and the Commonwealth of Virginia are in support of the
selected remedy.
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Greenwood Chemk^l Sirg Record Of Decision For OU-2 21
RESPONSIVENESS SUMMARY
EPA's Response To Proposed Plan Comments
The Greenwood Citizens Council and the Piedmont Environmental
Council submitted comments and questions regarding the Proposed
Plan in a letter dated November 21, 1990.*' The com-
ments/questions of concern are numbered one (1) through seventeen
(17). The letter of concern can be found in the Administrative
Record. Many of the comments raised issues of implementation
which will be addressed during the design phase. Below are the
responses of the EPA to comments/questions of concern.
1. The interim remedy for groundwater at the Greenwood Chemical
Site (Operable Unit 2 or OU-2) has been only conceptually design-
ed at this time. The final Remedial Design for the interim
remedy will be prepared after this Record of Decision is issued.
The ground water collection system in the Focused Feasibility
Study was developed primarily for cost estimation purposes. The
final design of the interim remedy may differ significantly.
Pumping test data is currently inadequate to predict capture
zones (or cones of influence). Pump data generated during the
implementation of the interim remedy will be used to make these
predictions and to design the final extraction system. Slug
tests are not appropriate in defining the characteristics of a
fractured bedrock aquifer.
At this time, it is unknown whether it is technically practicable
to remove contaminated groundwater from the overburden zone.
Groundwater contaminants have already reached bedrock and EPA
considers groundwater extraction in this zone to be viable.
2. All EPA geophysical investigations to date indicate it is not
possible to identify fracture orientations in the bedrock. VLF
radio signals may be used in the future for this purpose.
However, at this time, EPA does not consider the technique to be
adequately field-verified.
3. The water table in the aquifer of concern is known to be below
the overburden/rock interface at certain points already. This
fact will be considered during the Remedial Design.
4. The specific nature of the monitoring program for both the
treatment system effluent and monitoring wells will be developed
.during the Remedial Design. For cost estimation purposes, a
projected monitoring program was developed as part of the FFS.
These comments will be considered during the Remedial Design.
5. The technical scope of the treatability studies for ground
A copy of G.C.C.'s letter is attached.
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Greenwood Chemical Site Record Of Decision For OU-2 22
water treatment is being developed at this time. All results of
these treatability studies will be available to the public for
review prior to full-scale implementation of the remedy.
6. As stated in the ROD, residential well sampling will be part
of the groundwater monitoring program to be implemented under the
interim remedy for OU-2. The EPA intends to sample ten (10)
residential wells in the Winter of 1991. The specific nature of
the residential well sampling program under the interim remedy
for OU-2 will be developed during the Remedial Design. Monitor-
ing of water levels in residential wells will be part of this
program.
7. Groundwater treatment will not be considered to be complete
until effluent meets National Pollution Discharge Elimination
System (NPDES) requirements. All treatment steps necessary to
meet these criteria will be developed as part of the Remedial
Design.
8. Should cyanide levels in the South Pond continue to exceed
state and federal criteria protective of aquatic life after
remediation commences, the water in the South Pond will also be
treated to meet these criteria.
9. The EPA and the Commonwealth of Virginia will perform any
biological studies determined to be necessary to assure there are
no adverse impacts on the biological community of the stream from
the treatment plant discharges. These studies will likely
include, at a minimum, bioassays of the treatment system ef-
fluent.
10. The source and volume of water to cool the ozone decomposer
(if necessary) will be determined during the Remedial Design.
11. The treatment system will be designed to ensure all critical
parameters are controlled during operation as necessary. Con-
trols will be implemented to prevent the discharge of untreated
water.
12. Both the EPA and the Commonwealth of Virginia will determine
whether air permits will be required for the water treatment
facility. Should such a permit(s) be necessary, all substantive
permit conditions will be met.
13. Any steps necessary to assure effective chloroform removal
will be developed during the Remedial Design. While the FFS has
/projected the necessary reduction efficiency at 97.2 percent, the
actual efficiency required to meet NPDES provisions may differ.
14. Relative to the overall cost of the project, the cost of the
precipitant is not expected to be significant. The precipitant
to be used in this system will be identified during the Remedial
Design.
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Greenwood Chemical Site Record Of Decision For OU-2 23
15. Any complications presented by cyanide with regard to
precipitation will be addressed during the Remedial Design.
16. During Remedial Design EPA will assure that increased stream
flow will not "contravene reasonable, beneficial uses" of the
West Stream.
17. Discharge requirements of the Virginia State Water Control
Board may be reviewed by the public when they are finalized.
EPA's Response To Comments Related To Other Studies
The Greenwood Citizens Council (G.C.C.) is expected to have
access to (l) a description of planned treatability studies, (2)
data generated during treatability studies, (3) the identity of
residential wells to be sampled and frequency of such sampling,
(4) information regarding the planned treatment system, (5) the
identity of cooling water source and quantity, (6) design infor-
mation addressing chloroform removal, (7) information regarding
precipitation effectiveness in light of potential elevated
cyanide levels and (8) the State Water Control Board's final
discharge requirements.
The G.C.C. has also requested "a determination of whether or not
the cost of the preferred alternative has been calculated cor-
rectly". One objective of the FFS was to estimate the cost of
the alternatives. A more accurate estimate of the cost of the
selected alternative will be developed during the Remedial Design
and will be available to the G.C.C.
Recommendations provided in the G.C.C. 's comments will be con-
sidered during the Remedial Design/Remedial Action process.
Comments/questions by G.C.C. in the letter of November 21, 1990
which do not address the Proposed Plan for OU-2 at the Greenwood
Chemical site will be addressed by EPA through direct correspon-
dence with the G.C.C. This correspondence will become part of
the Administrative Record.
EPA's Response T
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Greenwood Chemical Site Record Of Decision For OU-2 24
Comment (C): Will the extraction of groundwater impact local
residential well supplies or stream flow?
Response (R): A review of available information indicates that
such impacts are not expected. In any case/ the system will be
designed to assure there are no such impacts.
C: What type of air emissions may be expected from the treatment
system?
R: The only air emissions expected to be generated by the treat-
ment system are carbon dioxide and (potentially) ozone. Carbon
dioxide emissions from the system are in no way expected to
present a health concern and are not expected to require any
control. (Note that a significant percentage of natural air is
carbon dioxide.) Should ozone be used in the treatment system,
ozone emissions will likely be controlled by an "ozone decom-
poser" which is expected to reduce any ozone emissions to within
regulatory requirements. EPA-sponsored studies have confirmed
that volatile organic compound emissions from the system are
insignificant and highly unlikely to require emission controls.
(The selected remedy's UV/oxidation system will destroy volatile
organic compounds.)
C: Will NPOES standards address all the contaminants identified
at the site?
R: All contaminants and their potential effects will be monitored
through bioassays of the treatment plant discharge. Bioassay
monitoring will assess the environmental impact of both known and
unknown Site-related contaminants.
C: How do NPOES requirements standards for the plant relate to
drinking water standards?
R: The objective of the NPDES requirements is to protect the uses
of the tributary (West Stream) receiving the plant discharges and
the uses of downstream waters. The most immediate concern in
this case is the protection of aquatic life in the West Stream.
To meet this objective, NPDES requirements, at a minimum, are
expected to be such that the West Stream meets state and federal
water quality criteria protective of aquatic life. These criter-
ia may be above or below drinking water criteria. The final
NPDES requirements will be identified during the Remedial Design.
During the public meeting, the EPA apparently stated that all
water discharged into the creek will meet drinking water stan-
dards prior to discharge. This statement was intended to reflect
the fact that a goal of Superfund is to restore known or poten-
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Greenwood Chemical Site Record Of Decision For OU-2 25
tial drinking water at Superfund sites (in this case, the aquifer
underlying the Greenwood Chemical Site) to drinking water stan-
dards where possible. Since the West Stream is not used for
drinking water purposes and is not expected to be used for such a
purpose, NPDES requirements for the plant discharge may not
necessarily be protective of the West Stream for drinking water
purposes. As noted above, the final NPDES requirements will be
developed during the Remedial Design.
C: Will untreated water be allowed to discharge to the West
Stream in the event of power or system failure?
R: The treatment system will be designed in a manner which will
prevent discharges of untreated water.
C: Will there be somebody onsite at all times while the treatment
system is operating?
R: The system may be designed to be at least partially automated
and thus not require a full-time operator. Should the system be
at least partially automated, the plan for such operation would
be developed during the Remedial Design.
C: Could the treatment system effluent be discharged to the
Morris Creek Treatment plant rather than the West Stream.
R: To date, the EPA has not considered this as an alternative in
this case. Consideration may be given during the Remedial Design
if this appears to be a reasonable option.
C: What are the advantages of the UV/oxidation treatment?
R: UV/oxidation treatment destroys organic compounds, while
carbon adsorption, the alternative, collects these compounds for
offsite treatment and/or disposal. In addition, the UV/oxidation
system is not expected to result in any significant air emissions
of volatile organic compounds or to require any controls for the
emission of such compounds.
C: Will an NPDES permit be issued for the Site?
'R: While an NPDES permit is not necessary, the treatment system
will meet all technical (substantive) NPDES requirements.
c: will biological or chemical monitoring of the treatment plant
discharge be performed?
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Greenwood Chemical Site Record Of Decision For OU-2 26
R: Both biological and chemical monitoring will be performed.
C: What will be the nature of the monitoring program for the
discharge of the plant?
R: The specific monitoring program for the plant will be devel-
oped during the Remedial Design.
C: Will ground water treatment proceed concurrently with soil
removal?
R: Some of these remedial activities may proceed concurrently.
This will be determined as remedial plans for the Site evolve.
C: Is there a plan to monitor the rate of groundwater contaminant
migration and residential well drinking water quality?
R: A ground water monitoring plan will be developed and imple-
mented as part of the interim remedial action addressing ground
water. Objectives of this plan will be to monitor ground water
contaminant migration and to assure that residential wells are
not being adversely impacted.
C: Does EPA know the volume of water that has to be treated or
the flow from the treatment plant at this time.
R: At this time, the EPA does not know the volume of water that
will be treated or the duration of the treatment system opera-
tion. Current EPA estimates indicate the flow from the treatment
facility range from 25 to 35 gallons per minute.
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GREENWOOD CITIZENS COUNCIL
November 21, 1990
Darius Ostrauskus
Remedial Project Manager
United States Environmental Protection Agency
841 Chestnut Building
Philadelphia, PA 19107
Dear Mr. Ostrauskus:
The Greenwood Citizens Council (G.C.C.) and the Piedmont Environmental Council
(P.E.C.) have, through our consultant HYDROSYSTEMS, Inc, performed a comprehensive
technical review of the information contained within the Administrative Record for the
Greenwood Chemical Company Site.
We feel that the level of technical detail presented for the preferred alternative was not
sufficient to allow us to adequately evaluate this alternative. At a minimum, documentation
of the systems' efficiency in treating the specific contaminants of concern and the specific
design details of the preferred alterative will be required in order to better evaluate this
alternative.
Treatability studies for both phases of the groundwater treatment (i.e inorganic and organic
treatment) are essential in order to fully evaluate the proposed systems' efficiency in
removing the contaminants of concern. The results of the treatability study should be made
available to the G.C.C and P.E.C. for review and public comment in order to fully evaluate
the alternative's applicability to the Site. In addition, we feel that the Draft Remedial
Design report should also be provided to the group for review and approval, prior to final
approval by EPA. The following presents the specific comments or questions regarding the
c/o Scott Peyton * Seven Oaks Farm * Greenwood, VA 22943
(703) 456-6418
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Mr. Darius Ostrauskus
November 21,1990
Page 2
Proposed Plan for Operable Unit No. 2 or information contained within the administrative
record.
Proposed Plan Comments
1. The design of the groundwater collection system appears to be inadequate based on
the information contained in the Focused Feasibility Study. This is particularly true
in the case of the overburden wells which are expected to have very low yields
resulting in very limited capture zones. For a groundwater recovery system to be
completely effective in containing and removing groundwater from a contaminated
area, the zones of influence of the wells should coalesce. In areas of known
contamination like the drum burial area, one or two shallow wells are not sufficient
to cover this area nor are seven wells enough to cover the entire Site. Calculations
should be made using slug or pumping test data to predict the cone of influence of
the wells so that an adequate spacing of the wells can be determined. Also, since the
contamination originates in the overburden zone, it would appear logical to
concentrate on removing the contaminated water in this zone before it can migrate
vertically into the bedrock aquifer.
2. The area of influence caused by the withdrawal of water from a well in fractured
rock will be irregular in shape and may extend well beyond the boundaries of the
Site. It might be beneficial to try to determine the orientation of the fractures in
advance of pumping in order to assess the sources of the water to these fractures,
especially as it relates to long-term pumping. A fracture beneath the Site which
contains contaminated water could produce water of good quality in a short period
of time if the fracture receives most of its recharge from areas other than the Site.
State-of-the-art geophysical techniques which measure magnetic fields generated by
; :— Greenwood Citizens Council
-------
Mr. Darius Ostrauskus
November 21,1990
Page 4
More importantly, no treated water should be allowed to be discharged to the West
Stream during the initial start-up period of the system without prior analysis. This
may mean that the treated water would have to be containerized onsite prior to
discharge. In the event that the effluent does not meet the discharge requirements
during this initial start-up period, this water should be recirculated through the
system until the effluent requirements are met
5. Describe in detail the proposed treatability studies for the preferred alternative. As
stated previously, we feel that access to all data from the treatability studies will be
necessary in order to adequately review the preferred alternative.
6. Although EPA stated in the public meeting that the residential wells would be
sampled during the interim remedial action, this is not mentioned in the FFS.
Exactly which wells does EPA intend to include in this monitoring and on what
frequency? At a nrniinnimt we feel that the residential wells should be monitored
on a semi-annual basis. These wells should include, but not be limited to the
following.
1) Hooks/Green
2) Gordon
3) Nobles
4) Carriage House
5) Fentress
6) Fix
7) J. Washington
8) Gibson (east)
Greenwood Citizens Council
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Mr. Darius Ostrauskus
November 21,1990
PageS
9) Simmons
Hurst
In addition, since all of the homes in the vicinity rely on groundwater for potable
water, routine water level monitoring should be performed on the closest household
wells to quantify any impacts occurring as a result of the long term withdrawal of
groundwater at the Greenwood Site.
7. After the groundwater treatment is complete, the effluent may exhibit an elevated
pH, temperature, and total dissolved solids concentration. Given that the effluent
may therefore exceed Site ARARs, what type of additional treatment does EPA
propose?
8. The water within the South Pond has been documented as containing cyanide in
concentrations exceeding the Virginia standard for the protection of aquatic life.
This water should be treated along with the water in Lagoons 4 and 5 during the
interim remedial action.
9. A biological study of the West Stream should be performed by EPA to obtain
baseline information on the creek prior to discharge. After the treatment has begun,
the effects of the discharge on the biological community should be evaluated by EPA
in order to ensure that there have been no adverse impacts on the stream due to the
discharge.
Greenwood Citizens Council
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Mr. Darius Ostrauskus
November 21,1990
Page 6
10. According to the Focused Feasibility Study, water will be required to cool the ozone
decomposer. What will be the source of this water and what volume of water will
be required?
11. The overall effectiveness of the preferred alternative will be largely controlled by the
pH and temperature of the system, the mixing efficiencies achieved, and the proper
ultraviolet and oxidant doses. EPA must ensure adequate controls of the wastewater
treatment system to ensure that each of these parameters are controlled throughout
the treatment process. In addition, safety controls should be designed into the system
to ensure that in the event of failure, untreated groundwater is not allowed to
discharge to the West Stream.
12. The manufactures of the Ultrox System have indicated that the users of their system
typically obtain an air permit We recommend that EPA determine whether or not
the requirements of an air permit are applicable to the use of this type of system at
the Greenwood Chemical Company Site.
13. According to the manufactures of the Ultrox System, the majority of the volatile and
semi-volatile organics present in the Site groundwater are very amenable to removal
through the use of this UV/Oxidation system. However, chloroform is more difficult
to remove with this system, and therefore must be considered carefully in the design
of the system. Given that the levels of chloroform at the Site require that the
treatment efficiency be greater than 972 percent in order to meet the ARARs, what
special procedures or design considerations does EPA intend to follow to remove the
chloroform from the groundwater at the Site?
Greenwood Citizens Council
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Mr. Darius Ostrauskus
November 21,1990
Page?
14. The preferred alternative (GW-2) appears to have been sized using CaS as the
precipitant instead of NajS. Was this also used to cost this alternative, and if so,
does this significantly affect the overall cost?
15. The use of precipitation to remove metals is often complicated when cyanide is
present in the wastewater. In this case, the cyanide ions may complex with certain
of the metals, making it difficult to precipitate, the metals as metal sulfides. How will
this be controlled by EPA?
16. EPA must determine the effects of increased flow on the aquatic life of the West
Stream and if necessary, the Stockton Creek. As stated in the Virginia Water
Control Board regulation, "Manmade alterations in stream flow shall not contravene
reasonable, beneficial uses including protection of the propagation and growth of
aquatic life." (VR680-21-01.4).
17. The G.CC and P.E.C would like an opportunity to review the discharge
requirements from the State Water Control Board to ensure that they are consistent
with other Superfund sites in the Commonwealth of Virginia.
Comments Related to Other Studies
1. One of the major deficiencies with the EPA studies performed to date at the Site is
the fact that the vertical extent of the contamination has not yet been determined in
Greenwood Citizens Council
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Mr. Darius Ostrauskus
November 21,1990
PageS
many of the source areas. This information is essential to the design for Operable
Unit No. 1. What does EPA intend to do in order to determine this information?
The data presented in the Remedial Investigation indicated that significant organic
and inorganic soil contamination was identified near the drum pile located in the
northeast comer of the property and adjacent to the Northern Warehouse. However,
the vertical and lateral extent of this contamination have not yet been determined
by EPA. What further investigations have been planned by EPA within these areas?
3. How does EPA plan on excavating the contaminated soils, given that in many areas
the contamination appears to extend to depths below the capabilities of conventional
excavating equipment?
4. Given the existing data, it appears that the onsite buildings will have to be
demolished in order to remove the contaminated soils below the concrete slabs.
Does EPA feel that the onsite buildings themselves may be contaminated and if so,
what will be done to decontaminated them?
5. The local citizens often consume deer or wildfowl which may forage and obtain water
at the Site. Does EPA feel that the meat of these animals could be contaminated
as a result of their exposure to the contaminants at the Site?
Greenwood Citizens Council
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Mr. Darius Ostrauskus
November 21,1990
Page 9
6. We feel that the contamination at the Site does warrant the placement of some form
of perimeter security for the entire Site. This should include locked fencing with
signs warning potential trespassers of the dangers associated with the Site.
In summary, we have reviewed the available data supporting the Proposed Plan for
Operable Unit No. 2 and the other studies performed at the Site to date. In general, we
feel that the proposed technology of Precipitation and UV/Oxidation should theoretically
be appropriate for the contaminants of concern at the Site. However, due to the fact that
there are presently many unknown design considerations still forthcoming with this
alternative, we would again like to reserve the right to have access to all data generated and
the right to publicly respond to this information. Until this information is available, we do
not feel we are yet in a position to support the proposed plan.
The specific items of information we are requesting are as follows: 1) a detailed description
of all proposed treatability studies; 2) all data generated from the treatability studies; 3) an
indication of which residential wells EPA intends on sampling and on what frequency;
4) information regarding any additional treatment EPA will be proposing to treat the
effluent which may exhibit an elevated pH, temperature, and total dissolved solids
concentration; 5) an indication of the source of water for cooling and the quantity of water
which will be required; d) information regarding the design considerations EPA will
implement for the removal of chloroform; 7) a determination of whether or not the cost
of the preferred alternative has been calculated correctly; 8) information regarding how
EPA will ensure the precipitation of the inorganic contaminants of concern given the
presence of cyanide in the waste stream; and 9) the State Water Control Board's discharge
requirements.
Our specific recommendations for inclusion in your plan, based upon the information now
available to us are as follows: 1) perform slug or pumping tests to adequately space the
Greenwood Citizens Council
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Mr. Darius Ostraoskos
November 21,1990
Page 10
recovery wells tq^ ensure that the zones of influence coalesce; 2) concentrate on removing
the contamination in the overburden zone, prior to allowing the contamination to migrate
vertically into the bedrock aquifer; 3) determine the orientation of the fractures prior to
initiating treatment to assess the source of water to the onsite fractures; 4) perform ground
water modeling or calculate a hydrologic water balance to ensure that adequate recharge
is occurring at the Site to maintain the general height of the Site water table above the
overburden/bedrock interface; 5) perform daily effluent monitoring for pH, temperature,
specific conductivity, and a volatile organic scan, and weekly effluent monitoring for metals
during the initial start-up period of the treatment system; 6) do not discharge treated water
to the West Stream until the aforementioned analysis are performed; 7) .include the water
within the South Pond in the treatment performed during the interim remedial action;
8) perform a biological study of the West Stream prior to and after discharge of the treated
water; 9) determine whether an air permit will be required for the use of the
UV/Oridation system at the Site; 10) perform the necessary studies or calculations to
determine the effects of the increased flow on the aquatic life in the West Stream; and
11) provide site security around the entire perimeter of the Site.
Sincerely, Sincerely,
Scott B. Peyton Timothy Lindstrom
Greenwood Citizens Council Piedmont Environmental Council
Greenwood Citizens Council
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Order numbar 930-503-161015-330 -001-001
page 1'I9 sat 15 with 131 of 131 items
** STANDARD, RE3. U I Fin:: Ell T
•^'CRITERIA, OH LIMITATION
•^PENNSYLVANIA WATER
(""QUALITY STANDARDS
RELEVANT AM 1)
APPROPRIATE
YES/NO
CITATION DESCRIPTION
25 Pa CODE SITE-SPECIFIC
SECTION 93 FOR DISCHARGE OF
"<•• TREATMENT SYSTEM
*«= EFFLUENT TO EAST
«"S . . BRANCH OF HOG RUN
Of CREEK.
DISCUSSION: ALT. 2 MONTHLY A V G. ~, 11A X, DAILY AVG. FOR TCE (3 5 f> UG/1);
VINYL CHLORIC)!- (0.02 5 O.OU UG/1); 5 1,1,1-TCA (605 B 1210 UG/1).
Item 5U
REGION :3
SITE NAME :GREENWOOD CHEMICAL CO
LOCATION : GFU.ENWOOO, VA
NTIS REt'OkT t:CPA/ROD/R03-91/117
ROD DAT?) :rJ01231
UV/OXINATION IS AL50 EXPECTED 13 35 EFFECTIVE IN TREATING CYANIDE.
REMAINING MAJOR COMPONENTS OF THIS ALTERNATIVE PROVIDE A PROVE!)
flECHAMISI FOK TREATMENT OF' METALS.
o
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9
9
9
9
O
DISCHARGES TO SURFACE MATER FROM THE TREATMENT SYSTEM PLANT WOULD
"SHEET NATIONAL POLLUTION [jj STH A RGE ELIMINATION SYSTEM (HPDES) '--
""REQUIREMENTS DEVELOPED PURSUANT TO THE FEDERAL CLEAN WATSR ACT-15, AND
IRGINIA WATER CONTROL ACT-IS. RESIDUALS GENERATED DURING THE
MENT OF INORGANICS WOULD BE HANDLED IN ACCORDANCE WITH THE
.
**ALL DISCHARGES TO SURFACE WATER FROM THE PLANT WOULD MEET NPDES
««REyuiRE!i5nrs A;ID VIRGINIA MATER CONTROL Acr-20. ORGANIC AND INORGANIC
WATER TREATMENT RESIDUALS MOULD BE DISPOSED OFKSITE AS REQUIRED BY
THEATt'.tN T, SrORf.GS AND DISPOSAL REGULATIONS UNDER RCRA, INCLUDING
LDRS-21. VOLATILE O'iGANICS E1ITTED FROM THE A1P. STRIPPER WOULD BE
THIS ALTiMNATIVF. COMrilNCS THE FOLLOWING MAJOR TREATMENT COMPONENTS:
ALKALINE CHLjRINATIDII, PRECIPITATION, FILTRATION, AIR STRIPPING AND
**CARHON ADSORPTI3U. pCSCHARGfiS TO SURFACE WATSR FROM THE PLANT WOULD
**HEET NPUKf; RKJJITiKIICNTS AND THE VIRGINIA WATER CONTROL ACT-25. ORGANIC
AND INORGANIC W.AT?JR T ~.{t.'. T "1E tl T RESIDUALS WOULD BE DISPOSED OFFSITE OR
REGEHKFlATF.i) AS HK3UIR?!) BY TREAT-TENT, STORAGE AND DISPOSAL REGULATIONS
UNDER RCKA, INCLUDING LUH3-26. VOLATILE ORGAN1CS EMITTiiD FROM THE AIR
WATER WILL pmvins FURTHER pitoTECiiON, EITHER BY RESTORING. THE AQUIFER
TO DRINKAilLK LEVELS OR THROUGH REQUIRING INSTITUTIONAL CONTROLS TO
i
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t,
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Order nurabac
pige 150
•}30l>03~151015- ROD
sat IS Kith Ul af
- i.» 31 - 0 01
131 items
PREVENT EXPOSURE,
'^COMPLIANCE WITH APPLICABLE OR RKLr.VANT AND APPROPRIATE REQUIREMENTS
•>*THE ENTIRE REMEDIAL ACTION WILL 3E PERFORMED ONSITS AND THUS BE EXEMPT
S3FROM' ADMINISTFUTIYK PERMIT REQ'J I RESENTS-30 . NEITHER MAXIMUM
CONTAMINANT LEVELS OH MAXIMUM CONTAMINANT LEVEL GOALS FOR GROUND WATER
UNDER THE FtDJHAL SAFE DRINKING WATLR ACT-31 ARE CONSIDERED BECAUSE THEY
"•CARE BEYOND THE SCOPE OF AM INTERIM ACTION SUCH AS ims-32. DISCHARGES
SSFHOM THE PLANT TO SURFACE MUTER UNDER ALTERNATIVES GH-2, GW-3, AND GW-U
^'DISCHARGES WOULD ALL MEET SUBSTANTIVE NPDES REQUIREMENTS AND THE
**VIRGINIA UATEU CONTROL ACT-33, AND ORGANIC AND/OR INORGANIC WATER
•^TREATMENT RESIDUALS WOULD BE DISPOSED OFFS1TE AS REQUIRED BY TREATMENT,
«*STOHAGE AND DISPOSAL REGULATIONS UNDE.R RCRA, INCLUDING LDRS-3U.
ADDITIONALLY, ANY FUGITIVE AIR EMISSIONS FROM THE GW-3 AND GW-<4 SYSTEMS
WOULD MEET APPLICABLE REQUIREMENTS UNDER NESHAPS, NAAQ3, AND VIRGINIA
REGULATIONS FOR THE CONTROL AND ABATEMENT OF AIR POLLUTION-35.
REPLACED PERIODICALLY TO MAINTAIN EFFECTIVENESS OF EMISSION CONTROL. NO
AIR EMISSION CONTROLS FOrt, VOLATILE OHGANICS ARE EXPECTED TO BE NECESSARY
W 11H A L T E R N A T I V K G W - 2 .
THE CASE OF EACH A. L1"V;R H-A TIV E, COMPLIANCE WITH TREATMENT DISCHARGE
<"*ARARS IDENTIFIED ABOVE SHOULD ASSURE PROTECTION OF STOCKTON CSSSK AND
•^^ITS TRIBUTARY (WEST STKE/VM).
IMPLEMENTAillLITY
THE TREATMENT FACILITY SHALL CONSIST OF A SERIES OF WATER TREATMENT
UNITS TO RrKOVS INORGANIC AND ORGANIC SUBSTANCES FROM THE PLANT
C^INFLUEIIT. THE PRI1ARY OBJECTIVE OF THE WATER TREATMENT IS TO REDUCE
«"*CONTAflI.!IANT LEVELS IN THE FACILITY EFFLUENT TO NPDES REQUIREMENTS
^'DEVELOPED 'PURSUANT TO VIRGINIA HATSR CONTROL ACT AND THE FEDERAL CLEAN
«">WATER ACT PRIOH TO DISCHARGE TO A TRIBUTARY OF STOCKTON CREEK (WEST
**STREAI1| . NPDES REQUIREMENTS MILL INCLUDE 7-DAY STATIC RENEWAL 3IOASSAY
«"*TESTS USING CEKIODAPHNIA AND PIMEPHALES PROMELA5, CONDUCTF.D IN' SUCH A
<">NANNEH AMD AT SUFFICIENT DILUTIONS TO DETERMINE THE "NO OBSERVED EFFECT
"^CONCENTRATION" AND CORRESPONDING CHRONIC TOXIC UNITS FOR SURVIVAL ANP
^REPRODUCTION OH GROWTH, AND A US-HOUR LC 50 AND CORRESPONDING ACUTE
•**TOXIC UNITS (OR A SIMILAR BIOASSAY TEST). SINCE THE EFFLUENT SHALL BE -
.C"*DISCHARG5D OHSITF.; T >1 E ADMINISTRATIVE REQUIREMENTS ASSOCIATED WITH AN
f<">NPDES PERMIT H52D NOT I5L' flETi HOWEVER, ALL APPLICABLE OR RELEVANT AND
''^^APPROPRIATE SU'JSTANTIVE NPDES KF.Q'J IREMENT5 WILL BE MET-3/J.
** :
«">TO NEtT THK SUiCJTANTIV E liPDES REQUI RErt E NTS OF CONCERN, REMOVAL OF BOTH
^'INORGANIC AMD ORGANIC SUBSTANCES WILL UE REQUIRED PRIOR TO EFFLUENT
**DISCHAIiGK. THE PRSCIPITATIOII SYSTEM WILL BE DESIGNED TO REMOVE
INORGANICS TO LEVELS WHICH MEET NPOE5-8ASED EFFLUENT STANDARDS.
REDUCTION OF INOHGHKICS IS ALSO NECESSARY TO OPTIMIZE THE ORGANIC
REDUCTION EFFICIENCY CJF THE UV/OXIDATION PROCESS. THE SPECIFIC
I
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