United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R02-88/069
September 1988
3EPA
Superfund
Record of Decision
G.E. Wiring, PR
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JO272-101
REPORT DOCUMENTATION
PAGE
1. REPORT NO.
EPA/ROD/R02-88/069
3. Recipient's Accession No.
4. Titln and Subtitle
SUPERF'UND'RECORD OF DECISION
GE Wiring .Devices, PR
First Remedial Action - Final
5. Report Date
09/30/88
Auttiord)
8. Performing Organization Rept. No
9. Performing Organization Name and Address
10. Project/Task/Work Unit No.
11. ContracUC) or Grant(G) No.
(C)
(G)
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
401 M Street, s.W.
Washington, D.C. 20460
13. Type of Report & Period Covered
800/000
14.
15. Supplementary Notes
16. Abstract (Limit: 200 words)
The GE Wiring Devices site is located in Juana Diaz, Puerto Rico. The General
Electric Company (G.E.) owns and operates a five-acre wiring devices plant at this site,
which assembled silent mercury switches from 1957 until 1969.• Approximately half a ton
of mercury was discarded along-with 4,000 yd3 of defective switch parts and plastic
scraps in an onsite waste-fill area about 1 acre in area and 1 to 4 feet deep. Several
residences are located approximately 400 feet south of the waste-fill area, which is
surrounded by a concrete retaining wall and a fence. Ground water in the area is used
a source of drinking water with a public supply well located approximately 1,500 feet
t of the waste-fill area. .In addition, ground water flows to the west toward the San
Jacaguas River. About 500,000 gallons of perched water has accumulated within the
waste-fill area as a result of precipitation/recharge. Evidence indicates that
contamination of the water table is occurring due to the migration of perch water
through the clay layer that exists beneath the waste-fill area. Approximately
1,500 yd3 of near-surface soil south and downgradient'of the waste-fill area has been
contaminated by mercury primarily as a result of previous surface runoff from the plant-
area, Tne primary contaminant of concern affecting the ground water, soil, and debris
is mercury.
(See Attached Sheet)
17. Document Analysis a. Descriptors
Record of Decision
GE wiring Devices, PR
First Remedial Action - Final
Contaminated Media: gw, soil, debris
c. COSATI Field/Group
18. Availability Statement
L
19. Security Class (This Report)
None
20. Security Class (This Page)
None
21. No. of Pages
21
22. Price
(SeeANSI-739.18)
See Instructions on Reverse
OPTIONAL FORM 272 (4-77>
(Formerly NTIS-35)
Department of Commerce
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\
/! EPA/ROD/R02-88/069
(' GH Wiring Devices, PR
/ First Remedial Action - Final
J 16. ABSTRACT (continued)
I
The selected remedial action for this site includes: onsite hydrometallurgical
treatment of the waste-fill materials, perched water, and contaminated near-surface soil
with disposal of the treatment residue in the former waste-fill area, followed by
covering with a clean soil cover, and onsite treatment of the process leaching agent
with discharge to a POTW; additional investigation of the ground water to determine the
extent of contamination; and limited ground water monitoring, provided there is no need
for ground water remediation. The estimated capital cost for this remedial action is
$1,912,870. There are no O&M costs associated with this remedy.
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DECLARATION STATEMENT
RECORD OF DECISION
SITE NAME AND LOCATION
GE Wiring Devices, Juana Diaz, Puerto Rico
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for
the GE Wiring Devices Site, in Juana Diaz, Puerto Rico, developed
in accordance with CERCLA, as amended by SARA, and, to the extent
practicable, the National Contingency Plan. This decision is
based on the administrative record for this site. The attached
index identifies the items that comprise the administrative
record upon which the selection of the remedial action is based.
The Commonwealth of Puerto Rico has concurred in the selected
remedy.
DESCRIPTION OF THE SELECTION REMEDY
The remedial action would remediate the waspe-fill area, perched
water, and the mercury contaminated near-surface soils to levels
which would be protective of public health. With respect to
contaminated soils downgradient of the waste-fill area, since the
mercury is primarily in the upper six inches of soil, the remedial
action would include remediation of the upper six inches of soil
at a minimum. Since groundwater data is limited, further investi-
gation and monitoring will be conducted during design to determine
the extent of groundwater contamination.
The major components of this remedial action are:
o
o
Further treatability studies during remedial design to insure
the implementability of hydrometallurgical processes, as well
as continued study of other treatment alternatives. •
On-site hydrometallurgical treatment of the waste-fill materials
(approximately 4000 cubic yards), perched water (approximately
1/2 million gallons) and contaminated near surface soils
(approximatedly 1500 cubic yards);
0 Treatment of the material to below health-based levels and
back-filling the waste fill area with the treated materials.
This area will then be covered with two feet of clean soil.
o
Additional investigation of the groundwater to determine the
extent of groundwater contamination;
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0 Limited groundwater monitoring (i.e. for a minimum of three
years), provided that the additional groundwater investigation
establishes that there is no need for groundwater remediation;
and
0 Confirmatory air monitoring and re-sampling of soil in residential
yards.
DECLARATION
Consistent with the Comprehensive Environmental Response, Com-
pensation, and Liability Act of- 1980 as amended by the Superfund
Amendments and Reauthorization Act of 1986, and the National Oil
and Hazardous Substances Pollution Contingency Plan, 40 CFR Part
300, I have determined that the selected remedy is protective of
human health and the environment, attains Federal and State
requirements that are applicable or relevant and appropriate for
this remedial action, and is cost-effective. This remedy satisfies
the statutory preference for remedies that employ treatment that
reduces toxi.city, mobility, or volume as a principal element and
utilizes permanent solutions and alternative treatment (or resource
recovery) technologies to the maximum extent practicable.
Because this remedy will not result in hazardous substances
remaining on-site above health-based levels, the five-year remedial
action review will not apply to this action.
Date William j^rtuszynjpf, P. E
Acting Regional Administrator
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Site Background
The G.E. Wiring Devices Site is located in the south central part
of the Island in Juana Diaz, Puerto Rico. The Site is northeast of
Ponce, close to the intersection of Routes 14 and 149 (See, figures
1 and 2). The General Electric Company (G.L.) operates a wiring
devices plant at this site that occupies approximately 5 acres ot
land. The property was originally leased from the Puerto Rico
Industrial Development Company (PRIDCO); the property is now owned
by G.E.
The source of contamination at the site is the waste-fill area
where defective parts from silent mercury switches were discarded.
These switches were assembled at the plant from 1957 until 196S.
Each switch contained a hermetically sealed stainless steel button
that encased a ceramic core, containing elemental mercury. Oft-
specification buttons were generally broken to reclaim the mercury.
The steel button shells, with residual mercury and ceramic cores,
were then discarded in the on-site waste-fill (pile) area where
other defective switch parts and plastic scraps were also discaraea.
Based on test pit excavations, the waste-fill area is approximately
1 to 4 feet thick 110 feet wide and 440 feet long. As calculated
in the Remedial Investigation, it is probable that roughly halt a
ton of mercury was discarded in the waste-fill area, based on
mercury switch,production and rejection documentation.
Several residences are located approximately 400 feet south ot the
waste-fill area. A concrete retaining wall and fence exist between
the site and the residences. Groundwater in the area is used as a
source of potable water. A public supply well is located approximately
1500 feet west of the waste-fill area.
S_ite History
'The site was proposed for inclusion to the National Priorities list
in December 1982. The original scoring was changed in June 1983
based on public comment. A Remedial Investigation and a Feasibility
Study (RI and FS) were conducted by the General Electric Company
(GE) through its contractor Law Environmental Services at the G.E.
Wiring Devices Site. These activities were performed pursuant to
an Administrative Consent Order II-CERCLA-30301 dated January 16,
1984. An RI report was submitted to the U.S. Environmental Protection
Agency for review in October 1986. EPA determined that additional
investigation was necessary in order to further define the nature
and extent of contamination at the Site. A Supplemental RI and a'n
FS report were submitted to EPA in draft in October and November
1987, respectively. The data collected during the RI were reviewed
for conformance with EPA data validation requirements. Subsequently,
EPA concluded that the quality of the data did not meet EPA specifi-
cations. Accordingly, in August 1988 EPA in cooperation with G.E.,
collected additional samples to complete the RI activities. Maps
depicting sampling locations and a summary of results are presented
in Figure 3 and 4 and Table 1, respectively.
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The draft FS did not fully evaluate treatment alternatives for
remediation of the Site and did not fully conform with the criteria
set forth in the Comprehensive Environmental Response, Compensation
and Liability Act of 1980, as amended (CLRCLA). As a result, EPA
entered into an agreement with the U.S. Bureau of Mines to evaluate
additional treatment technologies. The objectives of this evaluation
were to identify and assess additional treatment technologies which,
if implemented, could result in achieving a more permanent remedy by
reducing the toxicity, mobility or volume of the contaminant. EPA
then prepared an FS Addendum to further comply with CERCLA.
Co mmunity_ Relations
EPA has kept the local citizens and officials advised throughout
the Superfund process. Several public meetings were held in Juana
Diaz to discuss site developments. .Specifically, a public meeting
was held in February 1984 to discuss .the provisions of the
Administrative Order, as well as, to receive and respond to comments
concerning the site. In April 1987, a public meeting was held to
solicit comments on and discuss the findings of the RI. In September
1988, a public meeting was held to discuss and receive comments on
the studies and EPA's proposed remedial action plan. Questions ana
comments with their corresponding responses are summarized in the
attached Responsiveness Summary.
Site Character!stics
A silty clay to clayey silt unit exists immediately beneath the
waste-fill materials. This unit is believed to be continuous as
evidenced by its presence at 103 test pit excavations. The unit
appears to be from 1 to 4 feet thick based on monitoring well logs.
The permeability of the unit is in the range or 6-0 x 10~4 to
8.0 x 10~5. However, roots were observed in the shallow soils
which could increase the permeability of the soil by developing
channels through which contaminated leachate could flow. The silty
clay unit overlies the Holocene alluvial sediments deposited by the
Rio Jacaguas River as illustrated schemetically in Figures 5 and 6.
This alluvium is divided into four strata (See Figure 6); a very
silty fine to coarse sand, a sandy clayey silt, a silty sand and a
sand and gravel unit. Results of a resistivity survey indicate low
resistivities at depths of up to 12 feet in the central and western
portions of the waste-fill. This may be indicative that a zone of
high moisture content is present in the alluvial sands which underlie
the clay stratum in some areas of the waste-fill.
This moisture could be the result of slow downward migration ot
perched water through the silty clay stratum. Groundwater was
encountered within the alluvial sand and gravel formation at a
depth of about 45 feet below the existing grade. The grounawater
potentiometric gradient has been reported to be on the order of 0-01
to 0.006 ft./ft., with a groundwater flow direction to the west
towards the Rio Jacaguas River.
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Perched water accumulates within the waste-fill area as a result of
precipitation/recharge; the perched water generally consists of a
few feet of water perched above the top of the above-referenced
clay layer. The depth to the top of the perched water is approx-
imately 2 feet below the existing grade at the waste-fill surface.
The primary route for migration of mercury appears to be through
surface runoff from the waste-fill area. This results in the
contamination of surface soils to the south of the waste-fill area
(downgradient). The waste-fill area formerly received storm-
water runoff directly from the plant area, the runoff has since
been diverted by the construction of a drain pipe in 1982. The
potential for vaporization of the mercury also exists. In addition,
as stated above, the permeability of the clay underlying the fill
area is moderate and roots were observed in these soils. Also, the
resistivity data suggests that the migration of perched water
through the silty clay stratum has occurred.
Furthermore,, groundwater sampling suggests that the mercury has
migrated toj the water table. The highest concentration of mercury
in the deeper groundwater (i.e., 2.2 ppb) is slightly above the
Maximum Contaminant Level (2.0 ppb). However, this result was
obtained only in one sampling round approximately 50 feet away from
the waste-fill area. The location, number and depth of monitoring
wells are inadequate to fully characterize the extent of groundwater
contamination at the site. Therefore, further investigation of the
groundwater will be conducted during design of the remedial action
to determine the nature and extent of groundwater contamination.
This work will include installation of additional groundwater
monitoring wells and groundwater sampling. Additional remedial
action may be- necessary pending the results of this investigation.
The data collected during supplemental sampling indicates that
mercury was found in the following areas:
1) In an on-site surficial waste-fill (pile) area. This area
is approximately 110 feet in width and 440 feet in length and
about 4 feet deep, containing roughly 4000 cubic yards of
contaminated waste. The highest concentration observed in the
waste-fill area is 1400 parts per million (ppm) of mercury.
2) In perched groundwater within the waste-fill area. Approx-
imately 1/2 million gallons of contaminated water is found at
shallow depths (approximately 2 feet below the ground surface).
The highest concentration of mercury detected in the perched
water is 6.917 ppm.
3) In soils found approximately within the upper six inches
of the surface* (hereinafter referred to as "near-surface
w In general, mercury concentrations decreased with depth in these
soils. At depths below six inches mercury concentrations were
below health-based levels and approached background levels.
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soils") in an area which is in the direction of surface water
runoff from the waste-fill area (i.e., south or downgradient).
Since the number of valid soil samples is limited, the volume of
contaminated soil has been calculated by multiplying the
estimated areal extent of contamination by a depth of six
inches. The volume of contaminated soil has been estimated at
1500 cubic yards using this conservative approach. The highest
concentration of mercury detected in soils is 61.630 ppm.
S^te Risks
An endangerment assessment was conducted to determine exposure
routes and concentrations of mercury which may pose a risk to human
health. The endangerment assessment evaluated the baseline public
health risks associated with the site in the absence of any remedial
action. The primary exposure routes of concern which were evaluated
were ingestion of contaminated soils/waste-fill material and inhalation
of mercury vapors.* Data gathered for the EPA Mercury Health Effect
Update (1984) indicates that diet and ambient air inhalation yield
an intake of methyl mercury that is 18% of the Reference Dose (the
Reference dose is 0^.0003 mg/kg-day). Therefore, in evaluating the
risks posed by ingestion of contaminated soils/waste-fill material,
the!daily intake which would result in exceedence of 82% of the
reference dose was calculated using various assumptions. This
analysis indicates that mercury concentrations in excess of 38.8 ppm
may result in exceeding the reference dose. The sampling
data indicates that the concentrations of mercury in the soils and
waste-fill area exceed this value. In addition, air modelling was
conducted to predict the concentration of mercury vapors which
could be emitted given the concentration of mercury detected in
the soils and waste-fill materials. The modelling showed that
soil concentrations in excess of 16.4 ppm may cause the EPA
National Emission Standard for a Hazardous Air Pollutant (NESHAP)
to be exceeded. The NESHAP for mercury is 1 ug/m^. The
modelling also indicates that there is a potential risk associated
with vaporization of mercury from the waste-fill.area. Additional
air sampling will be conducted during the design to verify
whether the NESHAP is being exceeded.
Scope of Re_s_pons_e Action
The objectives of the remedial action are, in general, to achieve
clean-up levels of mercury in the waste-fill area (including perched
water) and downgradient soils which: adequately protect human health
~"As discussed previously, the groundwater database for the site
must be supplemented in order to fully characterize ground-
water contamination. Therefore, a supplemental groundwater
investigation will be'conducted during design. Consequently,
the risks posed by groundwater contamination will be evaluated
after completion of the investigation.
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and the environment, are cost-effective, and utilize permanent
solutions and alternative treatment technologies (e.g., those which
reduce the toxcity, mobility or volume of a hazardous substance)
to the maximum extent practicable. The remedial action must also
substantively comply with applicable or relevant and appropriate
requirements.
The remedial action would remediate the waste-fill area and the
mercury contaminated near-surface soils to levels which would be
protective of public health. With respect to contaminated soils
downgradient of the waste-fill area, since the mercury is primarily
in the upper six inches of soil, the remedial action would include
remediation of the upper six inches of soil, at a minimum. This
conservative approach should ensure the removal of all soil with
mercury concentrations above health-based levels. Since ground-
water data is limited, further investigation and monitoring will be
conducted during design to determine the extent of groundwater
contamination.
Description of Alternatives '•
A total of nine remedial alternatives were identified in the
Feasibility Study and addendum for dealing with the mercury
contamination at the G.E. Wiring Devices site. They were numbered
as follows:
1 No Action
*2 Cap with Extraction Wells
3 Fixation
4 Cap, Cut-off Walls and Extraction Wells
*5 Separate Waste by Mechanical Screening
*5a Alternative 5 with Only Off-site Disposal
*6 Separate Wastes by Mechanical Screening and Washing
*6a Alternative 6 with Only Off-site Disposal
7 Excavation and Redisposal On-site
7a Alternative 7 with Off-site Disposal
8 Thermal Treatment
9 Hydrometallurgical Treatment
The six alternatives that EPA considered in greatest detail are
summarized below. Each alternative addresses remediation of approx-
imately 4000 cubic yards of waste-fill material, 1/2 million gallons
of contaminated perched water and 1500 cubic yards of contaminated •
near-surface soils.
* Although evaluated in the FS, Alternative 2 was eliminated
because it is ineffective compared to Alternative 4.
Alternatives 5, 5a, 6 and 6a were eliminated based on technical
feasibility since the waste is not amenable to physical
separation.
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Alternative 1
NO ACTION - This alternative is used as a baseline for comparing
other alternatives and consists of leaving the site as it is. No
response actions would be implemented other than long-term monitor-
ing which would include a minimum of three wells hydraulically
downgradient of the waste-fill area and three wells south of the
waste-fill area (i.e./ in the area where contaminated soils have
been detected). Because the waste is left on/-site EPA must
review the remedial action no less than each 15 years after the
initiation of such action to ensure that the/remedial action
remains protective of public health and the environment. This
review of the remedial action is required under Section 12l|'(of
CERCLA. Land use restrictions would be required. !'
Alternative 3 ' >
- - • - !•-- —— i • i
i ;
FIXATION - This alternative consists of physically fixing the
waste with cement to resist erosion. Trenches would be dug ;
within the waste-fill area to facilitate drainage towards a Jsump.,
The sump, along with a leachate extraction well, would be installed
at the downgradient end of the waste-fill area. Perched wat'er |
within the waste-fill area would be pumped, via one extraction i
well and would be pretreated on-site prior to disposal at a'
publically owned treatment works (POTW). Treatment would
consist of filtration then carbon adsorption. Contaminated
near-surface soils will be excavated and consolidated in the
waste-fill area. The soils and waste-fill material would then be
mixed with cement to blend into an aggregate solid waste. A soil
cap would be placed over the waste-fill area. This alternative
does not require any long-term pumping of leachate. Long-term
groundwater monitoring would be conducted to verify the long-term
performance of this remedial alternative. Such monitoring would
be consistent with the description provided in Alternative 1, the
No Action Alternative. In addition, the remedial action would be
reviewed every five years as with Alternative 1. Land use restrict-
ions would be required for this alternative in order to ensure
that the integrity of the remedial action or the function of any
of the monitoring systems are not disturbed where contaminated
materials are left on site.
Alternative 4
CAP, CUT-OFF WALL WITH EXTRACTION WELLS - This alternative consists
of providing a multilayer impervious cap, slurry wall and leachate
collection system. Trenches would be dug within the waste-fill
area to facilitate drainage towards a sump. The sump with a
leachate extraction well would be installed at the downgradient
end of the waste-fill area. Perched water within the waste-fill
area would be pumped, via one extraction well and would be pre-
treated on-site prior to disposal at a POTW. Contaminated near-
surface soils will be excavated and consolidated in the waste-fill
area. The cap and slurry wall would then be installed. The cap
would be constructed of clay underlain by a synthetic membrane
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liner to further reduce infiltration, sand to promote drainage,
and top soil to promote vegetation and mininmize erosidn. The
slurry wall would surround the landfill and would be keyed into
the clay stratum. Pumping and treatment of leachate from the
landfill would be conducted on an as-needed basis and may be
required for an indefinite period of time. The treatment system
constructed for the treatment of perched water would be used to
treat the leachate and -'ould consist of filtration followed by
carbon adsorption. The treated leachate would also be disposed
of at a POTW. Long-term groundwater monitoring, consistent with
the description provided in Alternative 1, will be conducted
to assess the long-term effectiveness of this remedial alternative.
Since waste remains on-site above health-based levels the remedial
action must be reviewed every five years as with Alternative 1.
Land use restrictions would be required for this alternative.
Alternative^?
EXCAVATION AND CONSOLIDATION ON-SITE - This alternative proposes to
remove the contaminated material from the site and consolidate them
in a newly constructed on-site landfill to be located in the area
of contamination. The perched water would be pumped from the
waste-fill area in the same manner as in Alternative 4. The waste-
fill area would then be excavated and an impervious liner (i.e.,
with a 10"' permeability) would be placed on top of the clay
stratum. The waste and contaminated soils would then be placed on
the liner. A cap, slurry wall and leachate collection system
would be installed as with the preceding alternative. Pumping
and treatment of leachate from the landfill would be conducted on
an as-needed basis and may be required for an indefinite period
of time. The treatment system used for treating the perched
water would be used to treat the leachate and would consist of
filtration followed by carbon adsorption. The treated leachate
would also be disposed of at a POTW. Long-term groundwater
monitoring, consistent with the description provided in Alternative
1, will be conducted to assess the long-term effectiveness of
this remedial alternative. Since waste remains on-site above
health-based levels, the remedial action must be reviewed every
five years as with Alternative 1. Land use restrictions would be
required for this alternative.
Alternative 7a
ALTERNATIVE 7 WITH OFF-SITE DISPOSAL - This alternative is the
same as Alternative 7 except that the soils and waste from the
waste-fill area would be shipped to a RCRA Subtitle C hazardous
waste landfill in the mainland U.S., since there are currently
no permitted Subtitle C disposal facilities in Puerto Rico.
Confirmatory sampling would be necessary to verify that
contaminated materials left on site were below health-based levels
If further investigation of the groundwater confirms that there
is no significant health risked posed by groundwater, then limited
long term monitoring would be conducted (i.e., a minimum of three
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years consistent with the description provided in Alternative 1).
Land use restrictions would not be required.
Al ternative 8
THERMAL TREATMENT - This alternative proposes to treat the contami-
nated material on-site by heating the waste until all the mercury
is vaporized. Mercury has a relatively low boiling point (375°C)
and most of its compounds decompose into metallic mercury readily
upon heating. The mercury could then be recovered and recycled.
This material may have to be reclaimed in the mainland since
currently there are no facilities on the island which recover
mercury. There is a range of temperatures at which a thermal
treatment system for recovery of mercury from the waste could be
operated. At the high end of the range is incineration of the
waste. Since a high percentage of mercury is adsorbed to the
plastic materials in the waste-fill area, the low end of the range
would be a temperature at which the mercury could be recovered
from the plastic without decomposing the plastic (between 375°C
and 8508C). The optimal operating temperature of the thermal
treatment system would be evaluated during design. Another
potential thermal treatment option is vacuum distillation. In
this process the waste would also be heated to drive-off the
mercury and a vacuum would be applied to extract the mercury out
of the plastic. With either type of thermal treatment the mercury
vapor would be trapped and condensed. If selected, this process
would be designed to achieve levels protective of public health.
The residue from the process would be'disposed of on-site in the
former waste-fill area. A two foot soil cap would then be placed
over the former waste-fill area. Since the source of contamination
would be treated and the residuals left on-site would be below
health-based levels, no land use restrictions would be necessary.
In addition, if further investigation reveals no significant
ground water contamination, then only limited groundwater monitoring
would be conducted with this alternative (i.e., a minimum of three
years consistent with the description provided in Alternative 1).
Al t e r n a t i v e 9;
HYDROMETALLURGICAL TREATMENT - This type of treatment would be
utilized to treat the contaminated near-surface soil, perched
water and waste-fill materials. This alternative involves putting
the mercury into solution by using a leaching agent such as
cyanide, hypochlorite or nitric acid. The mercury would then be
recovered from the aqueous solution by using various metallurgical
techniques such as filtration and cementation/ precipitation.
The waste would be mixed with the leaching agent until 'the desired
level of mercury is extracted from the waste and put into solution.
The process stream from the leaching stage would then be filtered.
The residue from filtering would be disposed of in the former
waste-fill area and capped with soil as in Alternative 8. The
process would be designed to achieve treatment of mercury from
the waste to below health-based levels (i.e., less then 16.4 ppm).
Since it is anticipated that the treatment process could attain
treatment o;f mercury to below acceptable levels, the actual
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performance standard for the treatment process would be determined
by the maximum removal efficiency associated with the technology
with due consideration to the corresponding incremental cost
involved in achieving further removal. The mercury-laden liquid
from the filtering stage would then be subjected to cementation
or precipitation to remove the mercury. This result is achieved
by bringing the liquid in contact with materials such as stainless
steel, zinc, copper or aluminum.
During cementation, the mercury is exchanged with the metal and
precipitated out. The liquid would then be recycled back through
the process. It is anticipated that only one batch of leaching
agent would be needed. Upon completion of the process, the
remaining liquid would be treated on-site prior to discharge to a
POTW. Further treatability. studiesi",will be conducted during
design to optimize the treatment process. The process would be
designed to meet or exceed levels protective of public health.
Since the source of contamination would be treated and the residuals
left on-site would be below health-based levels, no land use
restrictions would be necessary. In; addition, if further investi-
gation reveals no significant ground! water contamination, then
only limited groundwater monitoring .would;be conducted with this
alternative (i.e., a minimum of threje years consistent with the
description provided in Alternative 'jl). '
i \
Analysis of Remedial Action Alternatives
The remedial action alternatives described above, were then
evaluated in accordance with the requirements of the National
Contingency Plan (NCP) and the Comprehensive Environmental Response,
Compensation and Liability Act as amended by the Superfund Amendments
and Reauthorization Act of 1986 (CERCLA). Nine criteria relating
directly to the factors mandated in Section 121 of CERCLA, including
subsection 121(b)(1)(A-G) and EPA's Interim Guidance on Selection
of Remedy (December 24, 1986 and July 24, 1987) were utilized for
this evaluation and are as follows:
0 Protection of human health and the environment
0 Compliance with applicable or relevant and appropriate
requirements (ARARs)
8 Long-term effectiveness and permanence
0 Reduction of toxicity, mobility or volume
0 Short term effectiveness
0 Implementability
0 Cost
0 Community acceptance
0 State acceptance
PROTECTION__OF_HUMAN_HEALTH AND THE ENVIRONMENT
Protection of human health and the environment is the central
mandate of CERCLA. Protection is achieved primarily by taking
appropriate action to ensure that there will be no unacceptable
risks to human health or the environment.
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Except for the No Action Alternative each of the alternatives
affords adequate protection of public health and the environment.
Alternatives 4 and 7 afford protection by providing a combination
of engineering (cap, slurry wall, etc.) and institutional controls
(land use restrictions). .Alternative 3 provides protection by
fixing the waste which limits the availability of mercury for human
exposure. Alternative 7 provides protection by removing the contam-
inated material from the site. Alternatives 8 and 9 provide protection
through treatment of the waste which reduces the concentration of
mercury down to or below health-based levels.
COMPLIANCE WITH ARARs
Section 121 (d) of CERCLA requires that remedial actions comply with
all applicable or relevant and appropriate Federal and State require-
ments for the hazardous substances, pollutants or contaminants that
are present on site, as well ;as any action-specific and locational
requirements. '}
Applicable requirements refer to those situations where the specific
legal or regulatory j urisdictjional prerequisites of a particular
statute or regulation are met;. Relevant and appropriate requirements
apply only to on site portion's of remedial actions and are those
which were developed to address problems similar to those encountered
at a site. A relevant and appropriate requirement must be complied
with to the same extent as if it were applicable.
With respect to requirements which are chemical-specific for mercury
contaminated soil and debris, there are no applicable or relevant
and appropriate requirements (ARARs).** Therefore, an Endangerment
Assessment was performed to determine the concentration of mercury
that would result in an acceptable risk level if left on-site. All
of the alternatives evaluated, with the exception of the No Action
Alternative, will result in site remediation which would minimize
exposure to mercury concentrations above acceptable health-based
levels. Air modelling indicates that 16.4 ppm is the lowest con-
centration of mercury which would pose a risk to public health.
Note, any potential risks posed by groundwater contamination
will be addressed following the supplemental investigation to be
conducted during design.
** Note, there are chemical specific ARARs for groundwater contamin-
ated with mercury (i.e., the Maximum Contaminant Level promulgated
pursuant to the Safe Drinking Water Act), however, the risks posed
by groundwater contamination will be addressed using the data
obtained during the additional groundwater investigation to be
conducted during the design of the remedial action.
-------
- 11 -
Air sampling will be conducted during remedial design to confirm
the results of this air modelling. If the monitoring verifies this
value, then 16 ppm will be the cleanup level for remedial action.
However, if the air monitoring indicates that there are no levels
exceeding the NESHAP, then 21 ppm, the lowest concentration of
mercury which would pose a risk to public health through ingestion,
will be used as the site cleanup level.
Potential action-specific ARARs were identified for the remedial
alternatives which were evaluated. A discussion of such potential
ARARs and the rationale for determining whether the requirement
should be considered as an actual ARAR is presented below.
With respect to locational ARARs, the site appears to be in close
proximity to known historic sites. A Stage IA survey will be
conducted during design to identify any potential undocumented
resources on or eligible for nomination to the National Register
of Historic Places.
For the alternatives which involve landfill closure (Alternatives 4
and 7) the RCRA closure regulations would be relevant and appropriate.
For Alternatives 4 and 7, the landfill would be closed in conformance
with 40 CFR Part 264, Subpart N which describes the closure requirements
for a RCRA hazardous waste landfill. . Alternatives 3, 8 and 9 which
treat the contaminated materials to below health-based levels would
be closed consistent with a RCRA clean closure regulations.
For alternatives which involve discharge of perched water to a
POTW, guidance from the EPA memorandum entitled "Discharge of
Wastewater from CERCLA Sites into POTWs" would be used, as well as
the permit requirements for the specific POTW. The guidance would
preclude the use of a POTW which is out of compliance with its
permit requirements. Accordingly, the treated perched water may
only be discharged to a POTW that is permitted to.accept such wastes
and is operating in compliance with that permit. The on-site
pretreatment must achieve the levels set forth in the POTW's permits.
The applicablity, relevance and appropriateness of the Land Disposal
Restrictions (LDRs) under RCRA were considered with respect to the
remedial alternatives evaluated. The LDRs would not be applicable
since the contaminated materials are not hazardous wastes. With
respect to relevancy and appropriateness, currently the only LDR
treatment standards which have been promulgated are for non-soil
and debris wastes. Treatment standards for soil and debris wastes
are currently being developed by EPA. In the interim, because there
are no treatment standards for soil and debris wastes and since
the contaminated materials found at the site are not sufficiently
similar to those for which such standards exist, the LDRs are not
considered relevant and appropriate.
-------
- 12 -
Section 121(d)(3) of CERCLA requires that if a remedial action
involves off-site disposal at a RCRA hazardous waste laadfill,
such disposal may only take place if releases are not occuring
from the unit which would receive the waste and any other releases
from the disposal facility are controlled under a corrective action
pursuant to RCRA. Alternative 7a, which provides for off-site
disposal, will comply with this requirement.
While permits are not required for on-site remedial actions at
Superfund sites, any on-site remedial action must meet the
substantive requirements of the permitting process. Therefore,
any alternative which includes on-site treatment (i.e., all
alternatives except No Action) would be designed and implemented
so as to comply with the substantive requirements of applicable
permitting processes.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Long-term effectiveness and permanence addresses the long-term
protection and reliability of an alternative. This is a relative
term and is therefore expressed in the degree of long-term
effectiveness and permanence associated with an alternative in
comparison to other alternatives being evaluated.
Alternative 1 The No Action Alternative offers no long-term
protection to human health or the environment. The potential
for direct contact with contaminated materials still exists.
Furthermore, erosion from the waste-fill area would continue to
contaminate downgradient (south of the waste-fill area) soils.
This alternative will require long-term monitoring indefinitely.
This alternative does not offer any degree of permanence.
Alternative 3 The Fixation Alternative would be somewhat effec-
tivein the long term in that contamination in excess of acceptable
health-based levels would be bound up in the cement and thus
exposure pathways (e.g., ingestion, inhalation) would be eliminated
However, the ability of this alternative to effectively prevent
the migration of mercury from the fixed material indefinitely is
uncertain. Therefore, long-term monitoring would be necessary
and the possibility exists that other remedial actions may also
be needed. Although quality control problems could be minimized
by removing the waste and.then processing "it instead of in-situ
fixation the waste remaining on-site would be above health-based
levels. Therefore, this alternative would not be more permanent
than Alternatives 7a, 8 and 9. The degree of permanence associated
with this alternative is greater than that which would be achieved
by Alternatives 1, 4, and 7 since the durability of cement is
greater than the construction material which would be used to
implement Alternatives 4 and 7.
-------
- 13 -
Alternative 4 The Impervious Cap with Extraction Well Alternative
is of limited effectiveness in the long term with respect to the
reliabilty of the remedial action. There is the potential for
remedy failure since the clay unit and underlying clay may not be
adequate barriers to mercury migration. This potential appears
to be further substantiated by the detection of mercury in the
groundwater. Since the waste is left on site untreated, this
alternative would require monitoring and maintenance indefinitely.
As stated above, this alternative is considered less permanent
than Alternative 3.
;'(
Al'ternative 7 The Excavation Alternative is of limited effective-
nedTi in the long term with respect to its ability to function
indefinitely. Although less likely, the potential for remedy
failure exists, as with Alternative 4. The potential for leakage
through the clays is mitigated relative to Alternative 4 by the
installation of a synthetic membrane liner under the contaminated
material, and above the clay stratum. As with Alternative 4,- this
alternative would also require indefinite monitoring and maintenance
Wit^h respect to the degree of permanence, although this alternative
offers ai greater degree of permanence relative to Alternative 4,
it' is far less permanent than Alternative 3.
Alternative 7a Alternative 7 with Off-Site Disposal, calls for
contaminated materials to be excavated down to acceptable health-
based levels. Since all wastes in excess of health-based levels
would be transported off site there would be limited groundwater
monitoring to confirm that the action was satisfactorily completed
and no long-term operation or maintenance. With respect to the
site this alternative offers a higher degree of permanence than
does Alternative 3.
Alternative 8 The Thermal Treatment Alternative is effective in
the long term in that it reduces toxicity of contaminated material
on site and decrease the concentration of mercury found on site
to acceptable health-based levels. As with the preceding altern-
ative, there would be limited confirmatory groundwater monitoring
and no long term operation or maintenance. Since the toxicity and
the concentration of mercury in the waste is reduced to health-
based levels, this alternative offers a higher degree of permanence
than does Alternative 3. With respect to the site, the degree of
permanence associated with this alternative is equivalent to
Alternative 7a. However, in a broader perspective this alternative
is more permanent than Alternative 7a because the waste is treated
instead of being relocated.
-------
- 14 -
Alternative 9 The Hydrometallurgical Alternative is effective in
the long term in that it effectively reduces the toxicity and
concentration of mercury in the contaminated material-on site
resulting in a decrease in exposure to acceptable health-based
levels. As with the preceding alternative, groundwater monitoring
would be limited confirmatory sampling with no long-term operation
or maintenance. Because the waste is treated this alternative has
a higher degree of permanence associated with it than Alternative
3. The degree of permanence is essentially equal to Alternative 8.
REDUCTION OF TOXICITY, MOBILITY OR VOLUME
This evaluation criterion relates to the performance of a remedial
alternative which involves treatment in terms of eliminating or
controlling risks associated with the toxicity, mobility or volume
of a hazardous substance. Since Alternatives 1, 4, 7 and 7a do
not involve treatment these alternatives were not evaluated against
this criterion.
With respect to toxicity, the data indicates that a substantial
portion of the total mercury present is in the organic form.
Orjganic mercury is much more toxic than inorganic mercury.
Therefore, alternatives which convert organic mercury into inorganic
mercury would result in a reduction in the toxicity of mercury.
Alternative 3 The Fixation Alternative is effective in reducing
the mobility of the contaminant by preventing further erosion and
reducing infiltration. This alternative, however, would increase
the volume of contaminated material. The toxicity of the waste
could potentially be reduced and exposure to mercury from the
waste is also reduced because the waste is bound up with the
cement.
Alternative 8 The Thermal Treatment Alternative would result in
a substantial reduction of the volume of contaminated material
on-site. Since the organic mercury is converted back into the
elemental form, the toxicity of the waste is significantly reduced.
The. mobility of the waste is reduced proportionally to the reduction
in concentration. This alternative would result in a reduction
in the concentration of mercury in the contaminated material by
roughly two orders of magnitude.
Alternative 9 The Hydrometallurgical Treatment Alternative would
also result in a substantial reduction of the volume of contaminated
material on-site. As with Alternative 8, the organic mercury is
converted back into the elemental form, thus the toxicity of the
waste is significantly reduced. In addition, the mobility of the
waste is reduced proportionally to the reduction in concentration.
This alternative would result in a reduction in the concentration
of mercury in the contaminated material by roughly two orders of
magnitude.
-------
- 15 -
Short-Term Effectiveness
The short-term effectiveness criterion measures how well an
alternative is expected to perform, the time to achieve performance,
and the potential adverse impacts of its implementation.
Alternative 1 The No Action Alternative does not offer any
degree of. protection, and therefore is not effective in the short-
term. There are however, no adverse impacts associated with
implementation of this alternative.
Alternative 3 The Fixation Alternative would involve excavation
of contaminated material. In the short term, there would be a
small potential for worker exposure to mercury contamination.
during consolidation of contaminated near-surface soils and
during the fixation process. However, this concern would be
addressed in the health and safety plan for construction activities.
This alternative should take approximately 2 years to implement.
Alternative 4 The Cap with Extraction Well Alternative would
also involve excavation of contaminated materials. Consequently,
in the short term, there would be the potential for worker exposure
to mercury contamination during consolidation of the near-surface
soils. The health and safety plan would address minimizing this
exposure. This alternative should take approximately 2 years to
implement.
Alternative 7 The Excavation and Consolidation On-site Alternative
would involve excavation of a greater volume of contaminated
material (approximately 5500 cubic yards) relative to Alternatives
3 and 4 (1500 cubic yards). This may result in an incremental
increase in the potential for worker exposure to mercury contamin-
ation during implementation. As stated above, this concern would
be addressed in the health and safety plan. This alternative
should take approximately 2 years to implement.
Alternative 7a Alternative 7 with Off-Site Disposal involves
off-site disposal and would thus increase truck traffic in the
area as well as the potential for accidents involving releases
of contaminated materials. As with the preceding alternatives,
in the short term there is the potential for worker exposure to
mercury contamination during implementation. The health and
safety plan would address minimizing this exposure. This" alter-
native should take approximately a year and a half to implement.
-------
- 16 -
Alternative 8 The Thermal Treatment Alternative, as with the
preceding alternatives would involve the potential for worker
exposure to mercury contamination during implementation. The
health and safety plan would address minimizing this exposure.
With this alternative mercury, from the off-gases would be condensed
and recovered, however, controls may be necessary to ensure that
mercury and other vapors are not released above acceptable levels.
This alternative should take approximately 2 years to implement
Alternative 9 The Hydrometallurgical Alternative, as with the
preceding alternatives, involves the potential for worker exposure
to mercury contamination during implementation. The health and
safety plan would address minimizing this exposure. In addition,
each of the leaching agents used in the process present health
and safety and process control considerations. Specifically, for
nitric acid, since the waste-material contains plastic there is
the potential for formation of picric acid which is explosive;
for cyanide there is the potential for evolution of hydrogen
cyanide gas; and for hypochlorite there is the potential for
evolution of chlorine gas. It should be noted, however, that
these are standard processes which are used in industry. These
potential health and safety concerns would be addressed in the
design of the process. For example, the formation of picric acid
would be controlled by adjusting the concentration of the acid,
the formation of hydrogen cyanide gas would be controlled by
buffering the pH with a base solution, and the formation of
chlorine gas would also be eliminated by buffering the pH using a
basic solution. This alternative should take approximately 2
years to implement.
IMPLEMENTABILITY
Implementability addresses how easy or difficult, feasible or
infeasible it would be to carry out a given alternative. This
covers implementation from design through construction and
operation and maintenance.
The implementability of the alternatives is evaluated in terms
of technical and administrative feasibility, the availability of
needed goods and services. All alternatives evaluated are technically
feasible. However, some implementation problems are inherent in
each of the alternatives.
Alternative 1 The No Action Alternative does not have any
implementation problems, however, it does not offer any
degree of protection.
For alternatives which involve handling of mercury-contaminated
soils it will be necessary to develop and implement a site specific
health and safety plan to reduce the potential for worker exposure
to mercury. Mercury contaminated material would be handled in
each of the Alternatives with the exception of Alternative Number 1,
the No Action Alternative.
-------
- 17 -
Alternatives which involve the off-site disposal of contaminated
perched water at a POTW may pose implementation problems with
respect to the availability of a POTW which complies with EPA's
guidance Memorandum entitled "Discharge of Wastewater from CERCLA
Sites into POTWS", dated April 15, 1986. In addition, permission
from the POTW to accept the waste may be necessary.
Alternatives 8 and 9 are considered to be implementable. Both
the data collected by the U.S. Bureau of Mines in their screening
of potential treatment alternatives and available information on
similar industrial processes suggest that these alternatives are
viable options. However, further bench and pilot scale studies
would be necessary prior to design and construction to further
evaluate the effectiveness of these alternatives'and to optimize
the operating and design parameters of the treatment process.
COST
The cost evaluation of each alternative is based on the capital
cost (cost to construct), long term monitoring, operation and
maintenance cost (O&M) and present worth costs.
Present worth analysis was used so that the cost of each alternative
could be compared on the same basis. The present worth value
represents the amount of money, if invested in the base year and
then expended as needed, would be sufficient to cover all costs
of the remedial action over its planned life.
The capital, O&M and present worth value for each alternative is
provided in Table 2.
COMMUNITY ACCEPTANCE
This evaluation criterion addresses the degree to which members of
the local community might support the remedial alternatives being
evaluated; and is addressed in the responsiveness summary.
COMMONWEALTH ACCEPTANCE
This criterion addresses the concern and degree of support that the
commonwealth government has expressed regarding the remedial altern-
atives being evaluated. Puerto Rico's Environmental Quality .Board
concurs with EPA's selection of Alternative 9.
-------
- 18 -
Selected Remedy
The selected remedial action is Alternative 9: Hyrometallurgical
Treatment.
This general type of treatment would be used for the contaminated
near-surface soil, perched water and waste-fill materials (approxi-
mately 1500 cubic yards, 1/2 million gallons and 4000 cubic yards,
respectively). This alternative involves putting the mercury into
solution by using a leaching agent such as cyanide, hypochlorite or
nitric acid. The mercury would then be recovered from the aqueous
solution by using various metallurgical techniques such as filtration
and cementation/precipitation. The waste would be mixed with the
leaching agent until the desired level of mercury is extracted from
the waste and put into solution. The process stream from the
leaching stage would then be filtered. The residue from filtering
would be disposed of in the former waste-fill area and
capped with two feet of clean soil. The process would be designed
to achieve treatment of mercury from the waste to below health-
based levels (See ARAR discussion). Since it is anticipated
that the treatment process could attain treatment of mercury to below
acceptable levels, the actual performance standard for the treatment
process would be determined by the maximum removal efficiency
associated with the technology with due consideration to the corres-
ponding incremental cost involved in achieving further removal.
The mercury-laden liquid from the filtering stage would then be
subjected to cementation or precipitation. This process is achieved
by passing the liquid through a material such as stainless steel,
zinc, copper or aluminum.
During cementation the mercury is exchanged with the metal and
precipitated out. The liquid would then be recycled back through
the process. It is anticipated that only one batch of leaching
agent would be needed. Upon completion of the process, the remaining
liquid would be treated on-site prior to discharge to a POTW.
Further treatability studies will be conducted during design to
optimize the treatment process. The process would be designed to
meet or exceed levels protective of public health. The estimated
cost associated with Alternative 9 is $1,912,870.
As discussed above, the location and number of existing monitoring
wells are inadequate to fully characterize the extent of groundwater
contamination at the site. Therefore, further investigation of the
groundwater will be conducted during design of the remedial action.
This work will include installation of additional groundwater
monitoring wells and groundwater sampling. Additional remedial
action may be necessary pending the results of this investigation.
If further groundwater investigation determines that there are no
current or future risks posed by groundwater contamination, then
limited groundwater monitoring would be conducted to provide further
verification (i.e., a minimum of three years). In addition, air
-------
- 19 -
modelling was used in the endangerment assessment to predict the
concentration of mercury vapors which could be emitted given the
concentration of mercury detected in the soils and waste-fill
materials. The modelling showed that the concentration of mercury
in soils and in the waste-fill area may cause the NESHAP to be
exceeded. The NESHAP for mercury is 1 ug/m^. Therefore, confirm-
itory air sampling will be conducted during the design to verify
the whether the NESHAP is being exceeded. During design, confirmitory
soil samples will also be collected from residential yards which
are downgradient in terms of surface water runoff from the site.
Statutory Determinations
Section 121 of CERCLA mandates that EPA select a remedial action that
is protective of human health and the environment, cost-effective,
and utilizes permanent solutions and alternative treatment technologies
or resource recovery technologies to the maximum extent practicable.
Remedial actions in which treatment which permanently and significantly
reduce the volume, toxicity or mobility of a hazardous substance is
a principal element are to be preferred over remedial actions not
involving such treatment.
Based upon the analyses presented herein the following conclusions
are reached:
0 Overall Protection of Public Health and the Environment
Alternative 9 provides protection through treatment of waste
above health-based levels for mercury
0 Compliance with ARARs
Alternative 9 would be designed to meet or exceed ARARs. As
stated above, this alternative would reduce the concentration
of mercury down to or below health-based levels in the absence
of chemical specific ARARs for soils and debris. The residuals
will be deposited on site and covered with clean soil consistent
with a RCRA clean closure.
0 Utilization of Permanent Solutions and Alternative Treatment
Technologies to the Maximum Extent Practicable
Alternative 9 is considered to be a permanent remedial action
since the concentration of mercury remaining on site, would be
below health-based levels. For this reason Alternative 9
has a greater degree of permanence relative to Alternatives 1,
-------
- 20 -
4 and 7 where wastes are left on-site, untreated, in concentrations
exceeding health-based levels. Although Alternative. 3 uses
treatment to reduce the mobility of the waste (and possibly
the toxicity) the concentration of mercury in the waste
remaining on-site would be above health-based levels. Therefore,
Alternative 9 is preferred over Alternative 3 because it does
not require indefinite management and monitoring of the site.
The degree of permanence associated with Alternative 9 is
equivalent to Alternatives 8 and 7a with respect to the site.
The d.egree of permanence associated with Alternative 7a is
limited in that it only addresses permanence in terms of on-site
conditions. Alternatives 8 and 9 would be permanent with
respect to off-site as well as on-site conditions.
Alternative 9 uses alternative treatment technologies to the
maximum extent practicable since it includes treatment of
all waste with mercury concentrations in excess of health-
based levels. The other treatment alternatives (i.e.,
Alternatives 3 and 8) also require the treatment of all waste
with mercury concentrations in excess of health-based levels.
However, Alternative 3 does not provide for recovery of mercury
from the waste. Thus, Alternatives 8 and 9 have the added
benefit of using alternative treatment technologies to the
maximum extent practicable while recovering mercury from the
waste thereby resulting in the conversion of a waste into a
usable material.
0 Preference for Treatment as a Principal Element
Alternative 9 satisfies the statutory preference for treat-
ment as a principal element of a remedial action since it
provides for treatment of organic mercury to inorganic mercury
which significantly reduces the toxicity of the wastes.
0 Cost-Effectiveness
Although Alternative 9 is not thetleast costly treatment
option it is cost-effective. The costs are reasonable in
light of the relatively small incremental (approximately
1 million dollars) cost associated with attaining a permanent
remedial action, with limited monitoring; no land use restrictions
and which utlizes treatment as a principal element.
In summary, Alternative 9 is the selected alternative, it is protec-
tive of public health, is cost-effective, and utilizes treatment
as a principal element. Alternative 9 would provide protection of
public health by using treatment to reduce the,concentration of
mercury on site to below health-based levels (See ARAR discussion).
-------
- 21 -
The treatment process employed would reduce the toxicity of the
waste by converting organic mercury into a less toxic inorganic
form and would reduce the volume of contaminated materials which
are above health-based levels. Since the residua.1 mercury concen-
tration in materials left on site would be below health-based
levels, this alternative is considered a permanent remedial action.
Studies conducted by the U.S. Bureau of Mines and available infor-
mation on related industrial processes suggest that this alternative
could be implemented. Further bench and pilot scale studies would
.be required to optimize the treatment process and minimize any
potential short-term impacts. Alternative 9 would be designed to
meet or exceed ARARs. The estimated cost for implementing Alternative
9 is $1", 912,870, which is reasonable in light of the degree of pro-
tection, treatment and permanence afforded by this alternative.
Currently, Alternative 9 appears to provide the best balance of
trade-offs among the alternatives examined in detial with respect
to the nine evaluation criteria. In addition to satisfying the
statutory preference for remedies which utilize treatment as a
principal element and for permanent remedies. EPA believes that
Alternative 9 is implementable based on current information.
However, since this alternative has not been fully demonstrated and
further treatability studies are necessary, EPA believes that it is
prudent to conduct additional treatability studies on other treatment
options concurrently with those to be performed for Alternative 9.
This approach would minimize any delay in remediating.the site, in
the event that hydrometallurgical treatment is not implementable.
-------
TABLE 1
CDM-FPC G.E. Wiring TES III WA 649
LWA Project 87525
INORGANIC RESULTS
Groundwater Samples
LSDG LSDG SEG SAMPLE
8073
8073
8073
8073
8073
8073
8073
8074
8074
8074
8074
8074
8074"
8074
8074
8074
8074
8074
8074
8075
8075
8075
1
2
3
4
5
6
6-DUP
1
2
3
4
5
5-DUP
6
7
8
9
10
11
17
18
19
GE-GW-01
GE-GW-15
GE-GW-14
GE-GW-12
GE-GW-11
GE-GW-10
GE-GW-10-DUP
GE-GW-JMT
GE-GW-07
GE-GW-06
GE-GW-05
GE-GW-16
GE-GW-16-DUP
GE-GW-B2
GE-GW-02
GE-GW-03
GE-GW-04
GE-GW-B3
GE-GW-B4
GE-GW-B5
GE-GW-B6
GE-GW-B7
TOTA
0
6525
3862
3445
5011
5778
6917
4046
6786
5220
3654
0
0
0
2
0
0
0
0
0
Ml
-UNI1
L
.0
.0
.8
.2
.2
.0
X
.0
.0
.0
.0
.0
X
.0
.3
.0
.2
.0
.0
.0
.0
.0
ERCURY
FS: UG/1
INORG
0.0
10.4
6.4
15.2
14.1
22.8
X
14.9
5.0
18.0
13.0
6.4
X
0.0
0.0
0.0
0.4
0.0
0.0
0.0
0.0
0.0
ORG
0
6514
3856
3430
4997
5755
6902
4041
6768
5207
3647
0
0
0
1
0
0
0
0
0
.0
.6
.4
.0
.1
.2
X
.1
.0
.0
.0
.6
X
.0
.3
.0
.8
.0
.0
.0
.0
.0
AMMONIA
-UNITS: MG/L--
as N as NH3 REMARKS
0.
570.
340.
300.
340.
420.
410.
400.
760.
590.
560.
890.
940.
0.
0.
0.
0.
0.
0.
17
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00 '
00
00
0.21
690.00
411.00
363.00
411.00
508.00 \
496.00 / Lab Duplicates
484.00
920.00
714.00
678.00
•
1077.00\Blind dup. -GE-GW-07
1137.00/Lab Duplicates
0.00-Bailer Rinsate Bl
0.00
0.00
0.00
0.00-Field Blank
0.00-Source Water Blan
ank
|
4 ,
*
Spoon Rinsate Blank
Dish Rinsate Blank
Auger Rinsate Blank
Soil Samples
8075
8075
8075
8075
8075
8075
8075
8075
8075
8075
8075
8075
8075
1 GE-S-1SU
3 GE-S-2SU
5 GE-S-3SU
6 GE-S-3DE
7 GE-S-4SU
9 GE-S-5SU
10 GE-S-6SU
11 GE-S-6DE
12 GE-S-7SU
13 GE-S-7DE
14 GE-S-8SU
15 GE-S-8DE
16 GE-S-14SU
19000.0
5188.0
24950.0
61630.0
1330.0
6180.0
4790.0
270.0
310.0
588.0
2850.0
485.0
270.0
MO; uu/ is
5360.0
3870.0
3790.0
8710.0
390.0
2430.0
530.0
170.0
220.0
0.0
980.0
450.0
160.0
13640.0
1318.0
21160.0
52920.0
940.0
3750.0
4260.0
100.0
90.0
588.0
1870.0
35.0
110.0
Blind Dup.JE-S-7SU
MERCURY values reported as 0.0 are actually < 0.2
AMMONIA values reported as 0.00 are actually < 0.1 for N and < 0.12 for NH3.
-------
TABLE 1 CONTINUED
Page 2
VOLATILE ORGANIC RESULTS
Groundwater Samples
LSDG
VOA
UG/L*
REMARKS
LSDG SEG SAMPLE TOTAL COMPOUND
REMARKS
8073
8073
8073
8073
8073
8073
8073
1 GE-GW-01
2 GE-GW-15
3 GE-GW-14**
4 GE-GW-12**
5 GE-GW-11**
6 GE-GW-10**
7 GE-GW-B1
ND
5.0 BENZENE
ND
ND
ND
ND
2.0 CHLOROFORM
Trip Blank
8074 2 GE-GW-07**
8074 4 GE-GW-05**
8074 5 GE-GW-16**
8074 6 GE-GW-B2
8074 7 GE-GW-02
8074 8 GW-GW-03
8074 9 GE-GW-04
8074 11 GE-GW-B4
ND
ND
ND
ND
ND
ND
ND
ND
(1)
Bailer Blank
Source water blank
* - All analyses performed at CLP detection limits
"*
** - These samples appeared to contain surfactants (foamed)
Analyses were performed on diluted samples, '
(1) - Blind duplicate of GE-GW-07
ND - Not detected or below CLP detection limit.
-------
SOURCE: DOCUMENT IS . PAGE NO.1 . JOB NU.HH1223.
WIRING DEVICES OF PUERTO RICO. INC.
GENERAL ELECTRIC COMPANY
GENERALIZED SETTING IN THE
VICINITY OF THE WASTE FILL
LAW ENVmONMENTAL
SERVICES
-------
RIO JAGAGUAS
SOURCE: DOCUMENT 30. PAGE NO. 10, JOB NO. MH2317.
WIRING DEVICES OF
PUERTO RICO, INC.
LAW ENVIRONMENTAL
SERVICES
SITE SETTING
GENERAL ELECTRIC
COMPANY
JUANA DIAZ, PUERTO RICO
JO.B NO. SS6331
-------
WIRING DEVICES OF PUERTO RICO. INC.
GENERAL ELECTRIC COMPANY
JUANA DIAZ, PUERU RICO
LAW ENVIRONMENTAL
INC.
POTENTIOMETRIC SURFACE ELEVATION
OF PERCHED WATER
(MID-MAY 19821
JOB NO. 55-6331 FIGURE 3
-------
-------
I EXPLANATION
•I MOLOCBNB ALLUVIUM
TBMTIAHV JUAN* DIAJt rOKMATIONl
• ILTI. CLA V». « LtMKTONB
TCNTIAMV VOLCANIC*
•••O WBLX, YIBLO IN GALLON* r(H MIMUTC
+ •ATTKMT Or WBLL*
I • OB*B«VATION WCLL
........ NOUOM •OUNOAMV or WILL rieuo
REFERENCE
MOOtriBO ArTBH ClUIfl. !••(
I MILES
I KILOMETERS
SOURCE:
.1.1 II
DOCUMENT 13, PAGE NO. 29, JOB NO. MH2317.
WIRING DEVICES OF PUERTO RICO, INC.
GENERAL ELECTRIC COMPANY
JUANA DIAZ, PUERTO RICO
LAW ENVIRONMENTAL SERVICES
MARIETTA. OCOMOIA
GEOLOGIC UNITS AND WELL
LOCATIONS IN THE VICINITY
OF THE SITE
JOB NO. SS6331
FIGURE>5
-------
MW-1
WASTE
FILL
MW-3
SCALE
SOURCE: DOCUMENT 30, PAGE NO. 33, JOB NO. MH2317.
WIRING DEVICES OF PUERTO RICO, INC.
GENERAL ELECTRIC COMPANY
JUANA DIAZ, PUERTO RICO
LAW ENVIRONMENTAL SERVICES
MARIETTA. OKOMOIA
SITE HYDROCEOLOCIC
PROFILE
JOB NO. SS6331
FIGURE 6
-------
TABLE 2
SUWARY OF COSTS
1.
3.
4.
7.
7a.
8.
9.
ALTERNATIVE
No Action
Fixation
Capping in place with
slurry wall
Excavation
Alt. 7 with off-site
disposal
Thermal treatment
Hydrometallurqical
CAPITAL (S)
- 0 -
834,150
374,540
529,380
2,563,110
5,473,900
MONITORING
and O&M m
71,270
82,540
82,540
82,540
4,000
4,000
treatment
1,912,870
- 0 -
------- |