United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R05-92/205
June 1992
SEPA
Superfund
Record of Decision:
Spickler Landfill, Wl
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NOTICE
The appendices listed in the index that are not found in this document have been removed at the request of
the issuing agency. They contain material which supplement, but adds no further applicable information to
the co'ntent of the c:tocument. All supplemental material is. however. contained in the administrative record
for this site.
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50272.101
REPORT DOCUMENTATION 11. REPORT NO. 1 ~ 3. Recipients Acceaeion No.
PAGE EPA/ROD/R05-92/205
4. 11tI8 8nd SubtItle 5. Report Date
SUPERFUND RECORD OF DECISION 06/03/92
Spickler Landfill, WI
6.
First Remedial Action - Final
7. Aulhor(a) 8. Perfonnlng Org8RiZllllon Rept. No.
II. Pwfonnlng OrgalniZllllon N8me and AcId..... 10. ProjectlTasklWork Unit No.
11. ConInct(C) Of Grant(G) No.
(C)
(G)
1~ SponaorIng Organization Nama and ~ 13. Type of RepoI'\ & Period Coverall
U.S. Environmental Protection Agency 800/000
401 M Street, S.W.
Washington, D.C. 20460 14.
15. SuppIam8nI8Iy No...
PB93-964118
16. Abstract (UmIt: 200 wonla)
The 10-acre Spickler Landfill site is an inactive municipal and industrial landfill
located in Spencer, Marathon County, Wisconsin. The site consists of a mercury brine
pit and two fill areas called the Old and New Fill Areas. The two fill areas are
separated by a crude oil pipeline right-of-way. The area surrounding the site is
sparsely populated and mainly rural. Ownership of the Spickler Landfill site changed
frequently during its years of operation. In 1970, the site began operations as a
municipal open dump. The same year, the state authorized the construction of a
clay-lined sludge disposal area at the site. No documentation exists that verifies
that the pit was clay-lined as planned. In 1971, mercury brine muds were disposed of
in this sludge disposal area, and the sludge disposal area was closed with a clay cap.
Other industrial wastes known to have been disposed of at the site include kalo dust,
which contained asbestos, and toluene, xylenes, methyl-ethyl ketone, and methylene
chloride. In 1972, the landfill was licensed to accept solid wastes, including
industrial waste, with the exception of toxic and hazardous materials. During 1973,
numerous violations were noted by the state, including failure to perform daily cover
operations and ineffective drainage control. In 1974, the state ordered the owners of
(See Attached Page)
17. Oocumant Anatyala .. DeacrlptOf8
Record of Decision - Spickler Landfill, WI
First Remedial Action - Final
Contaminated Media: soil, sludge
Key Contaminants: VOCs (benzene, PCE, toluene, and xylenes), other organics
(pesticides), metals (arsenic, chromium, lead), other inorganics (asbestos)
b. IdenlifieralOpen-Ended Terms
Co COSA 11 FieIdIGtoup
18. AvailabiMty Statement 19. Security CIa.. (Thia Report) 21. No. of Pages
None 40
20. Security Claaa (Thia Page) 22. Price
Nnnp
A 8 212 (4-77)
(See NSl-Z39.1)
See Instructiof18 on RelfefSe
(Formerly NTI~)
Depanment of Commerce
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EPA/ROD/R05-92/205
Spickler Landfill, WI
First Remedial Action - Final
Abstract (Continued)
the site to terminate operations and close the landfill. Between 1974 and 1975, most
closure and abandonment work was completed, including placement, grading, and seeding of
the landfill cover. A 1984 assessment revealed not only that areas of leachate seepage
occurred on both the north and south faces of the New Fill Area, but also that the
mercury brine pit had subsided and appeared to be collecting surface water. This ROD
provides a final remedy for the first operable unit (OU1), which consists of the mercury
brine pit, and the landfill. A future ROD will address final remediation of ground water
as OU2. The primary contaminants of concern affecting the soil and sludge are VOCs,
including benzene, PCE, toluene, and xylenes; other organics, including pesticides;
metals, including arsenic, chromium, and lead; and other inorganics, including asbestos.
The selected remedial action for this operable unit includes solidifying and/or
stabilizing wastes in the mercury brine pit based on treatability test results, followed
by installing and maintaining an impermeable cap; installing and maintaining a solid
waste cap over the New and Old Fill areas; installing and maintaining a leachate
extraction and treatment system in the landfills; discharging treated leachate to
wetlands, surface water, or a POTW based on Toxic Characteristic Leachability Procedure
(TCLP) test results; installing and maintaining an active landfill gas collection system;
monitoring ground water, leachate, and landfill gas; implementing institutional and
engineering controls; and inspecting the fence and landfill cap. The estimated present
worth cost for this remedial action is $4,859,000, which includes an annual O&M cost of
$113,000.
PERFORMANCE STANDARDS OR GOALS: Extracted leachate will be treated to appropriate
discharge levels as specified by federal and state requirements prior to discharge to the
wetlands, surface water, or a POTW. Capping and closure of the mercury brine pit are
subject to the requirements of RCRA, Subtitle C.
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DECLARATION FOR THE RECORD OF DECISION
SITE NAME AND LOCATION
Spickler Landfill
Spencer, Wisconsin
STATEMENT OF BASIS AND PURPOSE
This decision document represents the selected remedial action
for the first operable unit for the Spickler Landfill developed
in accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 (CERCLA), as amended by
the Superfund Amendments and Reauthorization Act of 1986 (SARA)
and, to the extent practicable, the National oil and Hazardous
Substances Pollution Contingency Plan (NCP).
This decision is based upon the contents of the administrative
record for the Spickler Landfill site.
The united States Environmental Protection Agency (U.S. EPA) and
the State of Wisconsin agree on the selected remedy for the first
operable unit.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this
site, if not addressed by implementing the response action
selected in this Record of Decision (ROD), may present a current
or potential threat to public health, welfare, or the
environment.
DESCRIPTION OF SELECTED REMEDY
This operable unit is the first of two operable units for the
site. The first operable unit addresses closure of the mercury
brine pit and the landfill, which is the source of groundwater
contamination, landfill gas control, leachate extraction and
treatment, and groundwater monitoring. The second operable unit
will. consist of a final remedy decision for groundwater.
The major components of the selected remedy for the first
operable unit include:
*
SOlidification/stabilization of the contents of the
mercury brine pit, followed by installation and
maintenance of an impermeable cap which meets the
requirements of NR 660 Wisconsin Administrative Code
(WAC).
1
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*
Install and maintain a solid waste cap which meets the
requirements of NR 504 WAC over the New and Old Fill
areas, excluding the mercury brine pit.
*
Install and maintain a leachate extraction and
treatment system in the landfills, excluding the
mercury brine pit.
*
Install and maintain an active landfill gas collection
system.
Monitoring of groundwater, leachate and landfill gas
and inspection of the fence and the landfill cap.
*
*
Institute deed restrictions on the property to prohibit
installation of drinking water wells and prohibit
construction on the landfill itself.
STATUTORY DETERMINATIONS
The selected remedy for the first operable unit is protective of
human health and the environment, complies with Federal and state
requirements that are legally applicable or relevant and
appropriate to the remedial action, and is cost effective. This
remedy utilizes permanent solutions and alternative treatment (or
resource recovery) technologies to the maximum extent
practicable. The remedy satisfies the statutory preference for
remedies that employ treatment as a principal element because the
stabilization of the mercury brine pit, if feasible as determined
by treatability studies, constitutes treatment.
Due to the volume of landfilled waste that would need to be
treated, treatment of this low level threat waste is considered
impracticable. The remedy employs engineering controls which
will be protective of human health and the environment to address
the low level threat posed by the landfilled waste.
Because this remedy will result in hazardous substances remaining
on-site above health-based levels, a review will be conducted
within ~ive years after commencement of remedial action to ensure
that"the remedy continues to provide adequate protection of human
:.A.. Regional Admin~strator
J U.S. EPA - Regl.on V
2
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RECORD OF DECISION
DECISION SUMMARY
SPICKLER LANDFILL
SOURCE CONTROL OPERABLE UNIT
SPENCER, WISCONSIN
Prepared By:
u.S. Environmental Protection Aqency
Reqion V
chicaqo, Illinois
May, 1992
3
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TABLE OF CONTENTS
I.
si te Location and Description........................... 6
II.
Site History and Enforcement Activities ................8
IV.
III. Community Relations Activities..........................9
Scope and Role of the Action...........................10
V.
VI.
Summary of Site
Characteristics....... ........ .........10
Summary of Site
Ri sks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
A. Contaminants of Concern.............................12
B. Toxicity Assessment................ ......... ........12
C. Exposure Assessment and Risk Characterization.......13
D. Current Site Conditions.............................13
E. Potential Future site Conditions....................14
F. Ecological Assessment...............................15
G. Rationale for Further Action........................16
VII. Summary of Al ternati ves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
VIII. Comparative Analysis of Alternatives...................20
IX.
X.
XI.
Selected Remedy....................... . . . . . . . . . . . . . . . . .22
Statutory Determinations............................... 23
A. Protection of Human Health and the Environment......23
B. Compliance with ARARs...............................24
c. Cost Effectiveness..................................29
D. utilization of Permanent solutions and
Alternative Treatment Technologies (or
Resource Recovery Technologies) to the
Maximum Extent Practicable..........................29
E. Preference for Treatment as a Principal Element.....30
XII. Responsiveness Summary..................following page 31
Documentation of Significant Changes...................30
4
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FIGURES AND TABLES
Fiqures
Followinq Paqe...
1
site Features
6
2
Property Boundary
6
3
Wetlands in the Vicinity of the site
7
Tables
1 Leachate Sampling Results - Organics 11
2 Leachate Sampling Results - Inorganic 11
3 Groundwater Exceedences of Federal and
State Standards 11
4 Residential Well Sampling Results (Round 2) 11
5 Chemicals of Potential Concern 12
6 Summary of Total site Risks 13
5
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I.
SITE LOCATION AND DESCRIPTION
The Spickler Landfill is located at S-2550 Eckes Road in the Town
of Spencer, Marathon County, Wisconsin. The site consists of ten
acres with two fill areas (Old and New Fill areas) which are
separated by a crude oil pipeline right-of-way, and a groundwater
contaminant plume. The landfill is located on an eighty acre
parcel of land. The landfill accepted municipal and industrial
wastes from July 1970 to March 1974. See Figure 1, site
features.
The site, as discussed in this document, consists of the Old and
New Fill areas, the mercury brine pit, and the groundwater
contaminant plume. The site is located on property owned by
Kenneth Fuller, but consists only of approximately 10 acres of
Mr. Fuller's 80 acre parcel of property. See Figure 2, property
boundary.
The Spickler Landfill is located in a sparsely populated, rural
area. The population of the Town of Spencer, Wisconsin in 1991
was 1,095. All residents are using private well water.
Mr. Fuller, who owns the property on which the landfill is
located, lives next to the landfill and operates a tree farm on
top of the landfill. There are two homes directly west of the
landfill and additional homes to the south and southwest of the
landfill. Groundwater is flowing to the northwest and could
impact Mr. Fuller's wells and the two homes to the south and
southwest. Sampling of these residential wells was conducted
during the remedial investigation but no evidence of
contamination was found.
Surface water from the site drains along several unnamed
intermittent streams which flow north and northeast. The
intermittent streams subsequently flow east and southeast
approximately 1.5 miles to the East Branch of the Yellow River.
The site geology consists of unconsolidated deposits of clayey
and sandy soils (glacial till) and granular soils developed by
the weathering of the underlying sandstone. The glacial till
deposits consist of lean clays (USCS classification: CL), sandy'
and gravelly clays (SC and GC) and sand soils with variable silt
and gravel contents (SM). The soils developed from the
weathering of sandstone consist of sand with low silt content
(SP), silty sands (SM) and sand soils with variable silt and clay
contents (SP-SC). The thickness of unconsolidated deposits
observed during monitoring well installation ranged from 4.0 feet
at well MW8S to 14.5 feet at well MW14D.
Clay soils were observed below the waste mass at leachate head
wells LH3 and LH4, located in the southern half of the Old Fill
Area. Soils observed below the waste mass at LH3 consisted of
approximately 6 feet of silt (OL and ML) and clay (CL). At
6
-------
..
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:::"
. MW20S
MW145 ,
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UGENO
. LEACHATE HEAD WElt.
. "",TORIIIO WElt.
FIGURE 1
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MW7S MW115 MW85
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SLUDGE DISPOSAL Pg: . "
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SITE FEATURES
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300 400 500
100 200
LEGEND APPROX. PROPERTY BOUNDARY
- - - - SITE LOCA nON
- - - - APPROX.
- - - - - PIPELINE
RESIDENCES
Dt, iDe.
II d eDnroDme
If ecoloD 8D
fiGURE ~NDARY
PROPERTY 80
-------
leachate head well LH4, approximately 2 feet of
encountered below the fill materials. The clay
Fill Area was not observed at LH1. Sandy soils
possible weathered bedrock) at well LH1.
At leachate head wells in the New Fill Area, 3 feet of clayey
soils (SC/CL) were observed below the waste mass at LH6 and 0.5
feet of clayey sand (SC) was observed below the waste mass at
LH7. The waste mass appears to be directly deposited over the
sandstone bedrock in the area of head wells LH2 and LH5.
clay (CL) was
under the Old
were present (SMi
The bedrock beneath the site consists of Upper Cambrian
sandstone, likely the Mt. Simon formation. The sandstone is a
multicolored, cross-bedded, fine to medium grained quartz
sandstone. Thin clay seams and clay minerals are dispersed
throughout the layering. Course grained layers and vuggy layers
occur occasionally, and horizontal and angular fracturing is
present at several locations.
The upper bedrock surface contains well developed fractures and
joints. Two fracture/joint sets were identified in the upper
bedrock layers. One fracture/joint set orientation at north 55
degrees (z10) east and another fracture/joint set orientation at
north 40 degrees (z10) west were identified. An additional
fracture/joint set orientation, in deeper bedrock layers, was
identified as north 10 degrees west and north 60 degrees (zlO)
east. Secondary porosity associated with the fracture and joint
systems was calculated at 1 to 8 percent.
The maximum thickness of sandstone observed during drilling was
at well MW15D, where sandstone occurred to a depth of 70.9 feet
from the ground surface (a minimum sandstone thickness of 63.9
feet).
Depth to groundwater in the area of the landfill is approximately
five to ten feet, and groundwater flows to the northwest. It is
unclear from information gathered during the remedial
investigation if there is lateral flow of groundwater through the
waste mass or not. The remedial investigation was conducted
during a drought period for Wisconsin and groundwater elevations
could have been depressed below normal water levels.
Most surface water runoff from the site appears to flow northwest
through a culvert under Eckes Road and into a wetland area. This
wetland is a State of Wisconsin classified wetland S3/E1K
(deciduous scrub/shrub and persistent emergent/wet meadow) and
S3K (deciduous scrub/shrub with wet soil). See figure 3. This
wetland is approximately 15 acres in size. The northwest part of
the wetland appears to have a drainage outlet channel which runs
north. It appears that the drainage from the east end of this
wetland and the flow from the site via the culvert under Eckes
Road flows north to a second wetland, classified as T3K and
7
-------
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approximately 10 acres in size, although there does not appear to
be any well-defined channel for this drainage path. The wetland
and all of its drainage outlets eventually flow into the East
Branch of the Yellow River. The site is not within the 100-year
floodplain of the East Branch of the Yellow River.
This wetland is in the headwater of the East Branch of the Yellow
River and the surface water runoff flowing through it appears to
be limited to that precipitation falling directly onto it and
that from a limited contributing watershed, part of which is the
Spickler Landfill site. Based on this assumption and
observations made of this area in the field, it would appear that
there is not sustained flow through this wetland throughout the
year. Flow occurs during and, for a limited time, after runoff
events (e.g., precipitation events and spring melt). As with
many headwater wetland areas, the duration of flow through the
wetland after the event depends on the volume of direct
precipitation runoff and subsequent release of this water from
surface and perhaps some subsurface (baseflow groundwater
discharge) storage areas. There is not enough data to determine
if the wetland is acting as a groundwater recharge area or
groundwater discharge area.
II.
SITE HISTORY AND ENFORCEMENT ACTIVITIES
The spickler Landfill was owned by Frederick Spickler and
operated by Spickler's Sanitation Service in 1970 as a municipal
open dump. In December, 1970,BASF Wyandotte received approval
from the Wisconsin Department of Natural Resources (WDNR) to
construct a clay-lined sludge disposal area at the landfill.
This area is approximately 100 feet by 100 feet in area, and 10
feet deep. There are no construction records for this disposal
area and therefore no verification that the pit was clay-lined as
planned. The pit was used from January to April 1971. While in
use, mercury brine muds were disposed in the pit. The pit was
closed with a clay cap in September 1971 and posted with
monuments (concrete posts). This area is known as the mercury
brine pit. Other industrial wastes known to have been disposed
in the Spickler Landfill include kalo dust, which contained
asbesto~, and toluene, xylenes, methyl-ethyl ketone, and
methylene chloride.
In August 1972, Carmen Way purchased the property from Frederick
Spickler, and the landfill was renamed Way's Sanitary Landfill.
Ways's Sanitary Landfill was licensed to accept solid wastes,
including industrial waste, with the exception of toxic and
hazardous materials. During 1973, numerous violations were noted
by the WDNR at Way's Sanitary Landfill. Among these were failure
to perform daily cover operations and ineffective drainage
control.
8
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In late 1973, Lawrence Ladick and Vernon Verjinsky, owners of
Midstate Disposal, purchased Way's sanitary Landfill. Midstate
Disposal operated the landfill until its closure in June 1975.
In March 1974, the WDNR ordered Midstate Disposal to terminate
operations and close the landfill. Between March 1974 and
February 1975, most closure and abandonment work was completed,
including placement, grading, and seeding of the landfill cover,
with the exception of the west slope of the New Fill Area
northeast of the pipeline right-of-way. In April, 1975,
Frederick Spickler re-purchased the land from Midstate Disposal.
In August, 1975, Kenneth Fuller purchased the property on land
contract from Frederick Spickler. In November, 1975, the land
contract was assigned to John Rooney.
On June 20, 1984, a Hazard Ranking System assessment was
conducted by the u.S. EPA. It was noted that areas of leachate
seepage occurred on both the north and south faces of the New
Fill Area, and that the mercury brine pit had subsided and
appeared to be collecting surface water. Soil samples taken from
landfill seeps were found to contain traces of mercury and
groundwater samples contained both organic and inorganic
contaminants. In July 1987, the spickler Landfill was placed on
the National Priorities List (NPL).
BASF corp." and Weyerhaeuser Co. signed an Administrative Order by
Consent to conduct the Remedial Investigation and Feasibility
Study (RIfFS). The order became effective on July 16, 1988.
III. COMMUNITY RELATIONS ACTIVITIES
A Community Relations Plan for the Spickler Landfill site was
finalized in 1989. This document lists contacts and interested
parties throughout government and the local community. It also
establishes communication pathways to ensure timely dissemination
of pertinent information. subsequently a fact sheet outlining
the Remedial Investigation (RI) sampling program was distributed
in October 1991. The Remedial Investigation/Feasibility Study
(RIfFS) and the Proposed Plan were released to the public in
December 1991. All of these documents were made available in
both the administrative record and an information repository
maintained at the Spencer Village Hall. A public comment period
was held from December 9, 1991 to February 10, 1992. All
comments that were received by U.S. EPA prior to the end of the
public comment period are addressed in the Responsiveness
Summary, which is attached to this 'ROD.
9
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IV.
SCOPE AND ROLE OF THE ACTION
This ROD addresses the first operable unit for the Spickler
Landfill site and will consist of closure of the landfills,
including the mercury brine pit, and groundwater monitoring.
ROD for the second operable unit will make a final remedy
decision for groundwater. The threats posed by this site to
human health and the environment are future exposure to seep
sediments and future use of the contaminated groundwater.
The
These threats will be addressed through the proposed cleanup
action for the first operable unit, which includes:
Landfill Closure
*
Capping the landfill areas with a clay
the requirements of NR 504 WAC.
Active landfill gas control system.
Leachate collection and treatment.
cap which meets
*
*
Mercurv Brine pit Closure
*
-Treatability tests for stabilization/solidification of
the contents of the mercury brine pit.
stabilization/solidification of the contents of the
mercury brine pit.
capping the mercury brine pit with a clay cap which
meets the requirements of NR 660 WAC.
*
*
Groundwater
*
Monitoring contaminated groundwater in the vicinity of
the site.
V.
SUMMARY OF SITE CHARACTERISTICS
The purpose of an RI is to characterize the nature and extent of
contamihation by hazardous substances at a site. The objective
of an RI is not to remove all uncertainty, but rather to gather
information sufficient to support an informed risk management
decision regarding which remedial action appears to be the most
appropriate for a given site.
The remedial investigation that was performed at the spickler
Landfill was designed to determine the nature and extent of site
contamination through a program of soil, groundwater, leachate
and surface water sampling. site geology and groundwater flow
patterns also were examined. The following conditions were
observed:
10
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*
Depth to groundwater in the area of the landfill is less
than five feet. It is unclear from data collected during
the RI if lateral flow of groundwater occurs through the
waste mass.
*
Explosive levels of combustible landfill gas were detected
in several new monitoring wells, an existing well, and in
three permanent gas probes on the west and north perimeters
of the Old Fill area.
*
The existing landfill cover does not meet the WDNR's clay
capping thickness requirements.
*
Asbestos was confirmed in a landfill cover soil sample.
*
There is a significant amount of leachate production and
build-up. The refuse is sitting in leachate (saturated)
which has collected on top of an impermeable clay layer
below most areas of the landfill.
*
Leachate samples from the mercury brine pit contained
elevated levels of calcium, magnesium, mercury and nine
organic compounds. See Tables 1 and 2.
*
Groundwater samples from monitoring wells showed exceedences
of Federal Maximum contaminant Levels (MCLs), Wisconsin
Enforcement Standards and Preventive Action Limits. MCLs
were exceeded for the following chemicals: benzene (MWS2 at
8 ugfl and MW10S at 6 ugfl), vinyl chloride (MWS1A at
39 ugfl) and barium (MWS2 at 4,690 ugfl). Groundwater
contamination has not moved off the property. Groundwater
contamination has migrated approximately 300 feet from the
waste boundary. Mercury was not detected in the groundwater
samples collected for round 1 in July 1990, but was detected
in monitoring well 15S at 0.2 ugfl and monitoring well SlA
at 0.31 ugfl during round 2 sampling in January 1991. See
Table 3.
*
Eight private wells near the site were sampled. One well
exaeeded the Wisconsin Drinking Water Standard for
manganese, one well exceeded for lead, one well exceeded for
iron, and one well exceeded for copper. The standards for
these inorganics are based on taste and odor considerations
and not on health considerations. One well slightly
exceeded the Wisconsin Drinking Water standard for chromium.
This standard is based on health considerations. The matter
has been referred to the Wisconsin Division of Health and
the WDNR Water Supply Program. contamination in these
private wells does not appear to be site related because the
wells are located off the property and the groundwater
contamination associated with the site has not been
documented to have moved off the property. See Table 4.
11
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Tab 1 e 1
SUlllllary of Organic Group Concentrations
leachate Samples
Spickler landfill RifFS
lown of Spencer, Wisconsin
Leachate Chlorinated Chlorinatcd
Head We 11 BETX Ethenes Ketones Phenols' Aromatics
--
54 137 10
55 50 6 201 2
L III 28,425 12b 443 554
LlI2 909 426
LlI4 9,490 3,005
LlI6 83 33 300
1.11/ I:iO
'. Not '~5:
1.
2.
3.
4.
Concentrations are in ug/l.
Groups where rou compounds Wel'C detected i:lr-e excluded from thl':> ru~le.
Sar.lple:; \'/ere nc,t collected from leachate head wells UI3 i\l1d I.It5.
.... ~I.)t d;?tf:<.f.e;!
5GH2/v I r!5MT /TEM/\(.EB/t!.
[v 1 r'-401-72]
13757.07
PAils
12
13
7
14
Phlhali\t.es
-------
II
tJ
6
7
))
10
-------
Table 2
SUiTma ry of Metals and Cyanide Concenlr~lions
leachate Samples
Spickler Landfill RiffS
Town of Spencer, Wisconsin
Minimum Maximllm Mean I ocat ion of No of Delee! ions/
Concentration Concenlration Concentration t1~~!~.!"m J~Qnc~n t !:~!1.Q!! __!!~~of -~~~I?!~~--
------
Aluminum 900 39,200 11,029 1111 7/7
Arsenic 2.5 15.8 8.0 LII4 7/7
Bari um 530 940 699 lII7 7/7
Beryllium 0.37 4.5 1.7 '-111 6/7
Cadmi 11m 0.40 21.7 5.0 '-116 7/7
Ca'cium 221,000 3,340,000 909,286 UI6 7/7
Chromium 6.3 91 44 '-III 7/7
Cobalt 415 415 415 '-116 1/7
Copper 28 99 46 LlI1 6/7
Iron 2,440 J05, 000 53,536 Ull 7/7
lead JO.5 78.9 43 1112 7/7
Magnesium 4,210 2 , JOO ,000 348,130 lII6 7/7
Manganese 376 35,800 7,315 LlI6 717
Mercury 0.21 666 167 lll6 4/7
Nickel 50 323 139 lII6 4/7
Potassium 15,000 104,000 42,543 UI6 7/7
Silver 41 41 41 Ul6 1/7
Sodium ~~ll, 400 50,600,UOO } , 'S09 , 114 '-116 7/7
Vanadium 9.3 63.1 24 I II I 7/l
Zinc 33 542 323 lII6 7/7
Cyanidt 13 13 13 LlI1 iih
Notes:
1:- Concentraliolls dre in 119/1..
2. Antimony, Selenium, and IhalLum WE're lI~l cietecrt'd ill leachate
3. The higher vallie between th~ ~,i1!11p12 iilill the field duplicClte 1$
calculalicn~. .
si.mples dnd hdve heen (omitted frllll: tllis lithle.
used for miniolllm, maxim.,m, and lIIeilll conc:entrat ion
-------
Tab1e 3
SU818ry 01 Round 1 NR 140 Groundwater Qua1ity Exceedances
Spickler landfi1l Rl/FS
Town 01 Spencer, Wisconsin
~R 140 N R 140 .10 CFR Part 141
Preventive Enforcemen~ Maximum Contfm1nant Concentrat1on\i;
~nalvte locat10n ~ction Limit (2) Standard 2) Level \3 'n Sampie
3enzene MW6S 0.067 5.0 5.0 Z
MWI0S 5
MWllS 3
52 8
S2A 4
Tetrachloroetnene S2A 0.1 1.0 5.0 4
'/inyl Chloride 51A 0.0015 0.2 2.0 39
~y 1 ene MWI0S 124 620 10.000 920
S2 2100
52A 300
~rsenic MWI0S 5.0 50 50 5.7
SIA 10.6
S2 26.8
S2A 35
9arium MW6S 200 1000 2000 220
MW75 290
f1W8S 210
MW9S 300
MWI0S 500
MW 11 S 960
I'1W13S 600
MW14S 200
I'1W16S 490
I'1W17S 450
I'1W19S 340
51 210
SIA 380
S2 4690
S2A 580
S3A 210
Cadmium I'1W8D 1 10 5.0 1.1
Chrom1um MWI0S 5 50 100 11. 7
I'1WllS 6.2
PW201 59.3
CODDer PW20 500 1000 1300 2250
Iron PW202 150 300 300 4280
PW203 50(5) 1720
~ead MWI2S . 5 50 10.1
MW19S 28.3
51 7.0
PW20 12.4
Manganese PW203 25 50 50 43.2
pw23 54.1
Footnotes:
~l concentrations are in ug/L.
2 Wisconsin Administrative Code Chapter HR 140.10. Tables 1 and 2 (10-01-90).
3 Drinking Water Standards and Health Advisories Table (4-91), U.S. EPA Office of
Drinkino water
(4~ ~A - Not Ava1lable
)- The MCl for lead 01 15 ug/L is not enforceable until December 1992. The present
.~
enforceable limit is 50 ug/L.
Hote:
--r7 The higher value between the sample and field duplicate is used in this table.
2. Mercurv was detected in wells SIA (0.31 ug/l) and 1'1W155 (0.2 ug/L) during the Round 2
samp Ii ng.
-------
Table 4
Summary of Round 2 Residential Well Sampling
NR 109 Safe Drinking Water Exceedances
Spickler Landfill RIfFS
Town of Spencer, Wisconsin
NR 109
Maximum NR 109
Contaminant Secondary Drinkiny Concentration
Analvte Location LeveH2) Water Standard(2 inS amp 1 e (1 )
Chrom; um PW 201 50 59.3
Copper PW 20 1000 2250
Iron PW 202 300 4280
PW 203 1720
Manganese PW 23 50 54.1
Footnotes:
(1) All concentrations are in ug/L
(2) Wisconsin Administrative Code Chapter NR 109.11 and NR 109.60
(March 1991)
-------
*
Surface water samples exceeded the Ambient Water Quality
criteria (AWQC) for manganese.
VI.
SUMMARY OF SITE RISKS
A baseline risk assessment was conducted for the Spickler
Landfill site and is presented in a document entitled "Baseline
Risk Assessment, Spickler Landfill RI/FS," August 1991. The
baseline risk assessment consisted of an identification of
chemicals of concern, toxicity assessment, exposure assessment,
risk characterization and ecological assessment.
A.
contaminants of Concern
Contaminants of concern are detected contaminants which have
inherent toxic/carcinogenic effects that are likely to pose the
greatest concern with respect to the protection of public health
and the environment (see Table 5).
B.
Toxicity Assessment
The purpose of the toxicity assessment is to develop human health
and environmental receptor toxicity and carcinogenicity data for
the chemicals of concern at the site and to provide an estimate
of the relationship between the extent of exposure to a
contaminant and the likelihood and/or severity of adverse
effects. The toxicity assessment is accomplished in two steps--
hazard identification and dose-response assessment.
The dose-response evaluation presented available human health and
environmental criteria for the contaminants of concern, and
related the chemical exposure (dose) to expected adverse health
effects (response). Included in this assessment are the
pertinent standards, criteria, advisories and guidelines
developed for the protection of human health and the environment.
An explanation of how these values were derived and how they
should be applied is presented below.
Cancer potency factors (CPFs) have been developed by u.S. EPA's
carcinogenic Assessment Group for estimating excess lifetime
cancer risks associated with exposure to potentially carcinogenic
chemicals. CPFs, which are expressed in units of (mg/kg/daY)-1,
are multiplied by the estimated intake of a potential carcinogen,
in mg/kg/day, to provide an upper-bound estimate of the excess
lifetime cancer risk associated with exposure at that intake
level. The term "upper-bound" reflects the conservative estimate
of the risks calculated from the CPF. Use of this approach makes
underestimation of the actual cancer risk highly unlikely.
Cancer potency factors are derived from the results of human
epidemiological studies or chronic animal bioassays to which
animal-to-human extrapolation and uncertainty factors have been
applied.
12
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TABLE 5
CHEM1:CALS OP PO'l'EN'1'1:AL CORCEIUf
Volatile Oraanic ComDounds (VOCs)
Metals/Inorganics
Acetone
Benzene
2-Butanone
Chlorobenzene
Chloroform
l,l-Dichloroethane
1,2-Dichloroethene (trans)
Ethylbenzene
2-Hexanone
Methylene Chloride
4-Methyl-2-pentanone
Tetrachloroethene
l,l,l-Trichloroethane
Trichloroethene
Toluene
styrene
vinyl Chloride
Xylene (total)
Aluminum
Arsenic
Barium
Beryllium
Cadmium
Chromium
Cobalt
Copper
Iron
Lead
Manganese
Mercury
~ickel
Selenium
Silver
Sodium
Vanadium
Zinc
cyanide
(III)
Semi-Volatile Compounds (SVOCs)
Pesticides/PCBs
Benzoic acid
Bis(2-ethylhexyl)phthalate
4-chloro-3-methylphenol
1,4-Dichlorobenzene
Diethylphthalate
2,4-Dimethylphenol
Di-n-butylphthalate
4-Methylphenol
gamma-BHC
Minerals
Asbestos
-------
Reference doses (RfDs) have been developed by U.S. EPA for
indicating the potential for adverse health effects from exposure
to chemicals exhibiting noncarcinogenic effects. RfDs, which are
expressed in units of mg/kg/day, are estimates of lifetime daily
exposure levels for humans, including sensitive individuals.
Estimated intakes of chemicals from environmental media (e.g.,
water) can be compared to the RfD. RfDs are derived from human
epidemiological studies or animal studies to which uncertainty
factors have been applied (e.g., to account for the use of animal
data to predict effects on humans). These uncertainty factors
help ensure that the RfDs will not underestimate the potential
for adverse noncarcinogenic effects to occur.
C.
Exposure Assessment and Risk Characterization
The exposure assessment identified potential pathways and routes
for contaminants of concern to reach the receptors and the
estimated contaminant concentration at the points of exposure.
The risk characterization quantifies present and/or potential
future threats to human health that result from exposure to the
contaminants of concern at the Spickler Landfill site.
Excess lifetime cancer risks are determined by multiplying the
intake level with the cancer potency factor. These risks are
probabilities that are generally expressed in scientific notation
(e.g., lxlO-6 or lE-6). An excess lifetime cancer risk of lx10-6
indicates that, as a plausible upper bound, an individual has a
one in one million chance of developing cancer as a result of
site-related exposure to a carcinogen over a 70-year lifetime
under the specific exposure conditions at a site.
Potential concern for noncarcinogenic effects of a single
contaminant in a single medium is expressed as the hazard
quotient (HQ) (or the ratio of the estimated intake derived
the contaminant concentration in a given medium to the
contaminant's reference dose). By adding the HQs for all
contaminants within a medium or across all media to which a
population may reasonably be exposed, the Hazard Index (HI)
be generated~ The HI provides a useful reference point for
gauging the potential significance of multiple contaminant
exposures within a single medium or across media.
from
given
can
D.
Current site Conditions
Exposure of children to chemicals in surface soil adjacent to the
landfill, borrow pit sediment and surface water, and seep
sediment were estimated for current site conditions (see
Table 6). In addition, based on a qualitative assessment of site
conditions, it was concluded that chemical exposure may occur
from air and cover soil. Based on analytical results, private
drinking water downgradient of the site does not appear to be
13
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Table 6
Total Site Risk Estimates
Human Health Evalqation
Spickler Landfill, Town of Spencer, Wisconsin
CURRENT SITE CONDITIONS
PODulation~
Trespassers (Children)
Hazard Indices
Cancer Risks
Medium
Total Risk
7e-04
5e-03
3e-01'
ge-03
3e-01
6e-08
3e-09
1e-06
6e-09
Surface Water - Borrow Pit
Sediment - Borrow Pit
Sediment - Seep
Surface So; 1
1e-06
FUTURE SITE CONDITIONS
Population:
On-Site Residents
Hazard Indices
Cancer Risks
Medium
Total Risk (1)
4e-03
2e-02
2e+OO
2e-02
3e+01
3e+01
3e-07
2e-08
5e-06
4e-08
3e-03
3e-03
Surface Water - Borrow Pit
Sediment - Borrow Pit
Sediment - Seep
Subsurface So; 1
Groundwater
Footnote:
(1) The "Total Risk" includes the risk due to groundwater, surface water,
sediment, and soil exposure.
Note:
1.
A noncancer risk estimate (hazard index) of greater than 1 indicates the
potential for noncancer effects (e.g., liver disease) to occur in humans
exposed at an assumed level and duration to a" contaminated medium. A
cancer risk level of greater than 1.0e-06 (i.e., one in a million) is
above the U.S. EPA's point of departure for Superfund sites.
-------
affected by the landfill; therefore, this medium was not
considered a source of chemical exposure under current
conditions. Under the assumptions made (i.e., children play on-
site 1 day/week, 8 months/year for 10 years), potential
noncarcinogenic hazards and potential cancer risks related to
surface soil, sediment, and surface water exposure were
estimated. The total risk under current land use was within the
risk range considered to be acceptable under the NCP
(carcinogenic risk of 1X10-4 to 1X10-6).
A qualitative assessment of risk was conducted for potential
exposure to air and the landfill cover soil under current land
use. Landfill gas production is occurring that may result in the
release of Volatile organic Compounds (VOCs) to ambient air. The
VOCs released will be carried downwind, which would expose nearby
residents. It is not known at what concentration exposures will
occur, therefore, it cannot be determined whether there is a
health risk associated with air exposure, but the potential does
exist.
During the RI, asbestos-containing materials were detected in
subsurface cover material. Also, materials potentially
containing asbestos were observed on the surface of the site in
isolated areas. Asbestos is a known human carcinogen, therefore
exposure to this mineral is a potential health concern.
Currently, the site is used as a tree farm, and tree farming
activities (e.g., tree spading) may cause the release of asbestos
to the air and cover soil. For these reasons, there is the
potential for exposure to asbestos through inhalation of air, and
incidental ingestion of asbestos contained in cover soil.
Asbestos concentrations in air have not been measured and cannot
be predicted in a meaningful manner. In addition, it is not
known what amount of exposure to asbestos may occur. However,
the potential for exposure may exist.
E.
Potential Future site Conditions
Potential future use of the property was assumed to be a
residential use scenario. To assess risks due to a potential
fut~re.residential use, the risks associated with subsurface soil
exposure and groundwater exposure were quantitatively assessed.
It was also assumed that future exposure to borrow pit surface
water and sediment, and seep sediment would be similar in nature
to current land use conditions, but that the frequency of
exposure would substantially increase (i.e., by five times).
Therefore, the resultant risk estimates for these media under
current land use conditions were multiplied by a factor of five
to estimate future levels of risk associated with these media.
It was assumed that the soils adjacent to the landfill may be
plowed in the future, exposing the subsurface soil. It was
assumed children may be exposed to soilS days/week, 8
14
-------
months/year, for 10 years.
Potential risk associated with future use of groundwater was
estimated using the present concentrations of chemicals detected
in monitoring wells at, and downgradient of the site, to estimate
exposure point concentrations. It was assumed that individuals
were exposed daily to chemicals of potential concern in water for
30 years, and that exposure occurred as a result of groundwater
ingestion, as well as dermal contact and inhalation wh~le
bathing. The majority of the total noncancer health risk was
associated with the potential exposure to arsenic, barium, lead,
manganese, and nitrites detected in groundwater. The majority of
the cancer risk associated with potential groundwater exposure
was due to vinyl chloride and arsenic.
The noncancer risk associated with exposure of children to
leachate seep-affected sediment in the future was associated
exposure to barium and manganese. The potential cancer risk
associated with exposure to arsenic.
with
is
See Table 6 for a summary of the total site risk estimates.
F.
Ecological Assessment
An ecological assessment of the Spickler Landfill site was
undertaken in order to identify any environmental resources at or
near the site that might be adversely affected by site
contaminants. An ecological assessment is a qualitative or
quantitative appraisal of the actual or potential effects of
hazardous waste site contaminants on plants and animals other
than humans and domesticated species.
The site and vicinity includes several disturbed habitats. Based
on field observations, the following habitats were present:
,northern mesic forest, conifer plantation, grassland area,
ephemeral pond, and emergent vegetation ponds (borrow pits).
Between some of these habitats are thin ecotones, or transitional
zones.
The site and surrounding area fauna is likely composed of species
common to forest edges or transition zones. Deer tracks have
been observed at various site locations, as have those of small
game mammals such as squirrels, raccoons and rabbits. The
presence of the property owner's dogs and occasional stray dogs
on the property probably restrict the occurrence of a wide
variety of small animals. The borrow pits do not appear to
support fish populations, but frogs and turtles are present.
The Natural Heritage Program of the WDNR does not have records of
threatened or endangered species or critical habitats in the
vicinity of the site.
15
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In summary, effects of the landfill or hazardous components of
the fill are not readily discernible on the ecology in the
immediate vicinity of the site. Areas of stressed vegetation,
possibly attributable to the landfill, were not noted.
G.
Rationale for Further Action
Actual or threatened releases of hazardous substances from this
site, if not addressed by implementation of the response action
selected by this ROD, may present an imminent and substantial
endangerment to public health, welfare, or the environment.
Based on the findings in the RI report and the discussion above,
a FS was performed to focus the development of alternatives to
address the threats at the site. The FS report documents the
evaluation of the magnitude of site risks, site-specific
applicable or relevant and appropriate requirements, and the
requirements of CERCLA and the NCP, especially the ground-water
protection policy, in the derivation of remedial alternatives for
the Spickler Landfill site.
VII. SUMMARY OF ALTERNATIVES
The principal objective of remedial action is to eliminate and/or
reduce th~ threat or potential threat to human health and the
environment posed by the areas of concern. The selection process
for remedial actions is developed to address the specific threat
posed in an area of concern, and considers the chemicals of
concern and the routes of exposure, as well as effective
technologies to address them.
The alternatives analyzed for the site are presented below.
Common Elements. Except for the "no action" alternative, all of
the alternatives being considered for the site include a number
of common components. Alternatives 2 through 5 include access
and deed restrictions and site monitoring.
Alternatives 2 through 5 include an NR 660 cap on the mercury
brine pit, active landfill gas control, and leachate collection
and ~reatment.
Alternative 1: No Action
The NCP requires that a no action alternative be considered at
every site. It is used as a basis for comparison during the
evaluation of other alternatives. The no-action alternative
assumes that nothing would be done to address potential public
health and environmental problems.
capital Cost: $0
Annual operation and Maintenance (O&M) Cost: $0
Present Net Worth (over 30 years): $0
16
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Alternative 2: Fencing and Deed Restrictions; NR 660 cap on the
Landfills and Brine pit; Active Landfill Gas Control; Leachate
Collection and Treatment; Groundwater Monitoring.
This alternative consists of fencing and deed restrictions to
restrict future access and construction on and near the
landfills. Site monitoring would be conducted to ensure
integrity of the fence and the landfill cap. Groundwater
monitoring and landfill gas monitoring will also be conducted.
An impermeable cap that meets the requirements of NR 660 WAC
(2 feet of clay, a synthetic membrane liner, 1.5 to 2.5 feet of
soil, and a minimum of 6 inches of topsoil) would be constructed
over the landfills, including the mercury brine pit. The cap
would cover an area of approximately 10.5 acres. This cap would
significantly reduce infiltration into the waste and minimize
leachate production. Minimizing leachate production will
significantly reduce the potential for leachate to enter
groundwater.
The impermeable cap will greatly increase the potential for
landfill gas to migrate off site because landfill gas is
naturally venting to the atmosphere through the the current cap
which is p~rmeable. Upon placement of an impermeable cap on the
landfills, landfill gas will either build up under the cap or
migrate horizontally from under the cap. For this reason, an
active landfill gas control system will be installed as part of
this alternative. Active landfill gas control consists of
extracting gas from the landfill using a blower connected to gas
extraction wells by a pipe system. The extracted gas is then
either vented to the atmosphere or burned in a flare if toxic
contaminants are present.
Leachate will be collected through the same wells as the landfill
gas. Leachate will not be collected from within the mercury
brine pit because the contents of the pit are relatively
impermeable and pumping the leachate out would be a slow process
that would take years to accomplish, and even then complete
leachate removal is unlikely because of residual pore water. The
collected leachate from the landfills will be treated either on
or off the site. On-site treatment would include a combination
of chemical, physical, and biological treatment technologies.
The treatment will address both organic and inorganic
contaminants. Treatment processes for organic contaminants could
include biodegradation, air stripping, carbon adsorption, reverse
osmosis and chemical oxidation. Treatment processes for
inorganic contaminants could include precipitation and ion
exchange. Treated leachate would then be -discharged to the
wetlands area near the property, to a Publicly Owned Treatment
Works (POTW), or to the nearest surface water body. Treatment
levels for leachate will be determined when the discharge
location is identified and will be in accordance with applicable
17
-------
or relevant and appropriate state and Federal standards.
Treatment residuals will be tested by the Toxic Characteristic
Leachability Procedure (TCLP), to determine if the waste is
characteristic of a hazardous waste as defined under the Resource
Conservation and Recovery Act (RCRA). Disposal of the waste will
be determined based on the results of the TCLP test.
capital Cost: $4,600,000
Annual Operation and Maintenance (O&M) Cost: $72,000
Present Net Worth (over 30 years): $5,200,000
Alternative 3: Fencing and Deed Restrictions; NR 504 Cap on the
Landfills; NR 660 Cap on the Brine Pit; Active Landfill Gas
control; Leachate Collection and Treatment; Groundwater
Monitoring.
This alternative includes the access restrictions and site
monitoring described in Alternative 2. A cap which meets the
requirements of NR 504 WAC (2 feet of clay,. 1.5 to 2.5 feet of
soil, and a minimum of 6 inches of topsoil) will be placed over
the landfill, but not over the mercury brine pit. This cap
limits infiltration to two to four inches per year, maintaining a
moist environment within the landfill that will encourage
biological degradation and ultimately stabilize the waste.
An impermeable cap meeting the requirements of NR 660 WAC will be
constructed over the mercury brine pit. The impermeable cap will
be placed over the mercury brine pit to stop the production of
leachate in the pit and therefore greatly reduce the potential
for any contaminants in this pit to reach the groundwater.
Leachate is produced when rain water mixes with the landfill
wastes. Leachate can then contaminate groundwater if it is moves
down through the ground to where the groundwater is located.
An active gas control system and a leachate collection and
treatment system will be installed as described in Alternative 2.
Capital Cost: $3,600,000
O&M Cost: $113,000
Presen~ Net Worth: $4,600,000
Alternative 4: Fencing and Deed Restrictions; NR 504 cap on the
Landfill; Solidify/stabilize the Brine pit and cap it with an
NR 660 Cap; Active Landfill Gas control; Leachate Collection and
Treatment; Groundwater Monitoring.
This alternative is identical to alternative 3, except that the
contents of the mercury brine pit will be solidified and/or
stabilized after treatability tests have been conducted.
Treatability tests will be conducted to determine the feasibility
of sOlidifying and/or stabilizing the wastes in the mercury brine
pit. SOlidification/stabilization of the mercury brine pit will
18
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ensure that leachate in the pit will not pose a threat to the
groundwater in the future, and future generation of leachate in
the pit will be minimized.
Leachate treatment residuals will be tested by the Toxic
Characteristic Leachability Procedure (TCLP), to determine if the
waste is characteristic of a hazardous waste as defined under the
Resource Conservation and Recovery Act (RCRA). Disposal of the
treatment residual waste will be determined based on the results
of the TCLP test.
Capital Cost: $3,833,000
O&M Cost: $113,000
Present Net Worth: $4,900,000
Alternative 5: Fencing and Deed Restrictions;
Landfill; Solidify/stabilize the Brine pit and
660 Cap; Active Landfill Gas control; Leachate
Treatment; Groundwater Pump and Treat.
NR 504 cap on the
Cap it with an NR
Collection and
This alternative is identical to alternative 4, except that it
includes a groundwater pump and treat system. Extracted
groundwater will be treated to address both organic and inorganic
contaminants. Treatment processes for organic contaminants could
include biodegradation, air stripping, carbon adsorption, reverse
osmosis and chemical oxidation. Treatment processes for
inorganic contaminants could include precipitation and ion
exchange. Treated groundwater will be discharged either to the
wetland to the northwest of the property, to a POTW, or the
closest surface water body. Treatment residuals will be tested
by the Toxic Characteristic Leachability Procedure (TCLP), to
determine if the residual is characteristic of a hazardous waste
as defined under the Resource Conservation and Recovery Act
(RCRA). Disposal of the waste will be determined based on the
results of the TCLP test.
Groundwater modelling was conducted as part of the Feasibility
study in order to estimate the time for groundwater to reach
cleanup standards (NR 140 WAC Preventive Action Limits) .
Modelling was conducted to estimate the time for groundwater to
naturally attenuate to cleanup standards versus the time for
groundwater to meet cleanup standards if a pump and treat system
were utilized. It was estimated that natural attenuation to
cleanup standards would occur in 38 years. Estimated cleanup
time with a pump and treat system was 12 to 23 years depending on
the amount of dispersion during pumping (dispersivity of 10 feet
versus dispersivity of 40 feet). The pumping and treatment of
the groundwater is estimated to reduce the groundwater cleanup
time from 38 years to between 12 and 23 years.
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Capital Cost: $4,300,000
O&M Cost: $217,000
Present Net Worth: $6,400,000
VIII.COMPARATIVE ANALYSIS OF ALTERNATIVES
In accordance with the NCP, the relative performance of each
alternative is evaluated using the nine criteria, 40 CFR Section
300.430(e) (9) (iii), as a basis for comparison. An alternative
providing the "best balance" of trade-offs with respect to the
nine criteria is determined from this evaluation.
A detailed analysis was performed on the five alternatives using
the nine evaluation criteria in order to select a site remedy.
Alternatives 4 and 5 are identical except for the groundwater
pump and treat. Because a final remedy for groundwater will be
addressed in the ROD for the second operable unit, Alternative 5
will not be evaluated further in this ROD. The following is a
summary of the comparison of each alternative's strength and
weakness with respect to the nine evaluation criteria. The nine
criteria are: 1) overall protection of human health and the
environment, 2) compliance with applicable or relevant and
appropriate requirements (ARARs), 3) long-term effectiveness and
permanence, 4) reduction of toxicity, mobility or volume through
treatment~ 5) short-term effectiveness, 6) implementability,
7) cost, 8) state acceptance, and 9) community acceptance.
overall Protection of Human Health and the Environment. All of
the alternatives, except Alternative 1 (no action), are
protective of human health and the environment. As the No Action
alternative does not provide protection of human health and the
environment, it is not eligible for selection and will not be
discussed further. Alternatives 2 through 4 reduce human
exposure to contaminants through institutional controls, site
monitoring, capping of the landfill and mercury brine pit,
landfill gas control and leachate collection and treatment.
Capping will reduce risks associated with wind transport of
exposed asbestos and surface soils contaminated by leachate
seeps; it will also substantially reduce surface water
infiltration into the waste material, which will reduce leachate
production presently migrating to the groundwater. The active
landfill gas control system will reduce risks associated with
migrating gas from the landfill to adjacent structures (e.g.,
basements) which could pose an explosion hazard. The leachate
extraction and treatment system will protect the groundwater from
any further contamination from landfill leachate. Alternative 4
includes sOlidification/stabilization of the mercury brine pit
which will ensure that the contents of the mercury brine pit do
not leach into the groundwater in the future.
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compliance with Applicable or Relevant and Appropriate
Requirements (ARARs). Alternatives 2 through 4 will meet all
ARARs associated with this first operable unit, and are described
in detail in Section X of this ROD, Statutory Determinations.
Long Term Effectiveness and Permanence. Alternatives 2 through 4
provide for long term effectiveness and permanence by controlling
the spurce (landfill waste). Alternative 2 is the most effective
at controlling the source in the long term because the NR 660 WAC
impermeable cap will virtually eliminate any leachate generation
in the future. Alternatives 3 and 4, although effective, are not
as permanent at controlling the source because leachate will
continue to be generated, thus requiring continuous leachate
collection and treatment. Alternative 4 is more permanent at
controlling the source than alternative 3, however, because it
addresses the contents of the mercury brine pit.
SOlidification/stabilization of the contents of the mercury brine
pit will ensure that the pit can support a hazardous waste cap
and minimize the likelihood that groundwater will become
contaminated from the contents of the mercury brine pit in the
future.
Reduction of Toxicity, Mobility, or Volume Through Treatment.
All of the .alternatives (2 - 4) will utilize treatment to reduce
the toxicity, mobility and volume of leachate. None of the
alternatives propose to treat the contents of the landfill
because this would be very costly and would not significantly
reduce risks below the level which will be achieved through
capping. Alternative 4 will utilize sOlidification/stabilization
to stabilize the brine pit.
Short-Term Effectiveness. Alternatives 2 through 4 involve
construction at the site. Protection of site workers and the
community during the implementation of the alternatives will be
addressed by site safety plans. capping of the landfill,
leachate extraction and treatment, and landfill gas control, as
provided in Alternatives 2 through 4, are expected to have an
immediate beneficial effect on groundwater contamination.
Implementability. There will be some implementation problems for
all the alternatives. Institutional controls typically pose
problems with implementation and enforcement. The capping of the
landfills may cause access problems to the site, as there is only
one access road to the property, which abuts the toe of the
landfills in places. The cap may render part or all of the road
inaccessible. The combination solid waste/hazardous waste caps
proposed for the landfills/mercury brine pit may pose
construction problems since this type of mixed cap construction
does not appear to be typical. A final determination regarding
groundwater remediation will not be made until the second
operable unit ROD is issued.
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Cost. The estimated capital, annual operation and maintenance,
and 30-year present worth costs for each of the alternatives are
presented below:
Alternative
capital Cost
O&M
Present Worth
-----------------------------------------------------------------
1
2
3
4
5
$ 0
$ 4,587,000
$ 3,561,000
$ 3,833,000
$ 4,300,000
$ 0
$ 72,000
$113,000
$113,000
$217,000
$ 0
$ 5,217,000
$ 4,587,000
$ 4,859,000
$ 6,400,000
Alternative 3 is the least costly of Alternatives 2 through 5.
state Acceptance.
The WDNR concurs with u.s. EPA's decision.
community Acceptance. U.S. EPA received two comments from the
public. Both of the comments are addressed in the attached
Responsiveness Summary.
IX.
SELECTED REMEDY
Based upon consideration of the requirements of CERCLA, the
detailed analysis of the alternatives, and public comments,
u.S. EPA has determined that Alternative 4 (fencing and deed
restrictions; NR 504 cap on the landfills;
solidification/stabilization of the mercury brine pit and NR 660
cap; active landfill gas control; leachate collection and
treatment; and groundwater monitoring) is the most appropriate
remedy for the first operable unit for the spickler Landfill site
in Spencer, wisconsin. The second operable unit will address a
final remedy for groundwater.
Alternative 4 will achieve substantial risk reduction through
capping of the landfills with a NR 504 cap,
sOlidification/stabilization of the mercury brine pit and capping
the mercury brine pit with a NR 660 cap, active landfill gas
control, and leachate treatment. The capping of the landfills
and leachate collection will considerably slow down the rate at
which contaminants from the waste mass enter groundwater. An
NR 504 cap is considered protective for the landfill, excluding
the mercury brine pit, because it provides protection against
direct contact with waste and will reduce infiltration of
precipitation; an NR 660 cap would not provide any significant
increase in protection in connection with the landfill. An
NR 660 cap is appropriate for the mercury brine pit because the
wastes disposed in the pit are RCRA listed waste K071, mercury
brine sludge. The NR 660 cap is appropriate because the purpose
of closing the mercury brine pit is to eliminate, not simply
reduce, infiltration into the pit. stabilization/solidification
and an impermeable cap on the mercury brine pit will ensure that
leachate currently in the pit will not enter the groundwater and
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the impermeable cap will significantly reduce any future leachate
production in the mercury brine pit. Groundwater monitoring will
be used to detect any changes in groundwater quality and extent
of groundwater contamination at the site. Groundwater monitoring
will not reduce potential risks associated with future use of the
contaminated groundwater. The second operable unit will consist
of a final remedy decision for groundwater. The active gas
control will ensure that nearby buildings are protected from the
possibility of landfill gas migrating to basements with the
potential for an explosion. Alternative 4 is cost-effective
because the effectiveness of sOlidification/stabilization of the
mercury brine pit and groundwater monitoring will be proportional
to the cost of these measures. Alternative 4 provides the best
balance of benefits, with respect to the nine evaluation
criteria, among all of the alternatives considered for closure of
the spickler Landfill site.
x.
STATUTORY DETERMINATIONS
Under its legal authorities, U.S. EPA's primary responsibility at
Superfund sites is to undertake remedial actions that achieve
adequate protection of human health and the environment. In
addition, section 121 of CERCLA establishes several other
statutory requirements and preferences. These specify that, when
complete, the selected remedial action for this site must comply
with applicable or relevant and appropriate environmental
standards established under federal and state environmental laws
unless a statutory waiver is justified. The selected remedy also
must be cost-effective and utilize permanent solutions and
alternative treatment technologies or resource recovery
technologies to the maximum extent practicable. Finally, the
statute includes a preference for remedies that" employ treatment
as a principle element that permanently and significantly reduce
the volume, toxicity, or mobility of hazardous substances. The
following sections discuss how the selected remedy meets these
statutory requirements. .
A.
Protection of Human Health and the Environment
The selected remedy protects human health and the environment
through containment of long-term, low-level threat hazardous
substances, sOlidification/stabilization of the mercury brine pit
followed by an impermeable cap, landfill gas control, treatment
of leachate and groundwater monitoring. Extracted leachate will
be treated to appropriate discharge levels as specified by
Federal and State requirements prior to discharge to the
wetlands, surface water or a POTW. Solidification/stabilization
of the mercury brine pit will be preceded by treatability tests
to determine the viability of these processes. The mercury brine
pit will be capped with an impermeable cap meeting the
requirements of NR 660 WAC. The landfills will be capped with a
solid waste cap meeting the requirements of NR 504 WAC.
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Groundwater monitoring will be conducted to detect any change in
the quality or location of the groundwater contamination
associated with the site.
B.
Compliance with Applicable or Relevant and Appropriate
Requirements
The selected remedy will comply with the Federal and more
stringent state ARARs listed below:
Chemical Specific ARARs
Chemical-specific ARARs regulate the release to the environment
of specific substances having certain chemical characteristics.
Chemical-specific ARARs typically determine the extent of clean-
up at a site.
i.
Surface Water
Federal ARARs
Surface water quality standards for the protection of human
health and aquatic life were developed under section 304 of the
Clean water Act (CWA). The Federal Ambient Water Quality
Criteria (AWQC) are nonenforceable guidelines that set pollutant
concentration limits to protect surface waters that are
applicable to point source discharges, such as from industrial or
municipal wa~tewater streams.
state ARARs
The State has promulgated wisconsin Water Quality Standards and
criteria (WWQC) under Chapters NR 102 and 105, WAC, and the
procedures for calculating the toxic effluent limits under
Ch. NR 106, WAC, based on the Federal AWQC developed by U.S. EPA.
NR 102, 104 and 207 WAC also apply in determining water quality
based limits. The State WWQC are applicable if leachate from the
Spickler Landfill site is pumped, treated and discharged into the
wetlands or surface water body, as are the antidegradation
standards in Ch. NR 207 WAC.
The State is authorized to implement the National pollutant
Discharge Elimination System (NPDES) program. For discharge of
treated water and/or leachate, the applicable or relevant and
appropriate requirements are dependent on the point of discharge.
The procedural and substantive requirements of a wisconsin
pollutant Discharge Elimination System (WPDES) permit, under
Ch. NR 220, WAC, would be applied to the discharge of leachate
into the wetland, POTW or surface water body, since these
discharge points are considered to be off-site. Subject to the
approval of the U.S. EPA, effluent limits for surface water or
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wetland discharge will be established by the WDNR. Ch.
WAC, requires that the effluent limits be based on the
application of best available technology (BAT) prior to
discharge.
NR 220,
ii. Publicly Owned Treatment Work (POTW)
state ARARs
Ch. NR 211, WAC, is applicable to pretreatment effluent limits
for the discharge of wastewater to a POTW.
iii.
Air Emission Standards
Federal ARARs
42 U.S.C. section 7401 et. sea. (Clean Air Act) is applicable to
any off gases produced by the gas control system and/or leachate
treatment systems.
state ARARs
Ch, NR 445, WAC provides air pollution control standards and is
applicable to any off gases produced by the gas extraction and/or
leachate treatment systems.
iv.
Land Disposal Restrictions
Federal ARARs
40 CFR Part 268 is applicable for placement of the contents of
the mercury brine pit (RCRA listed K071 waste) and any leachate
treatment residuals which are RCRA characteristic under the TCLP.
state ARARs
Ch. NR 675.20, WAC, provides land disposal restrictions treatment
standards and are applicable for placement of the contents of the
mercury brine pit (RCRA listed K071 waste) and any leachate
treatment residuals which are RCRA characteristic under the TCLP.
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Location-specific ARARs
Location-specific ARARs are those requirements that relate to the
geographical position of a site. These include:
Federal ARARs
Executive Order 11990 - Wetland Protection - is applicable for
this site if the discharge of treated leachate and groundwater is
to the wetlands.
section 404 of the CWA regulates the discharge of dredge or fill
material to waters of the United states. Construction of surface
water discharge points may be regulated under section 404 of the
CWA; therefore, the substantive requirements of section 404 would
be relevant and appropriate to the remedial action at the site if
the discharge of the treated leachate and groundwater is to the
wetlands or a surface water body.
state ARARs
Ch. NR 115, WAC - Wisconsin's County Shore land Protection
Program, Ch. NR 1.95, WAC - Wetlands Preservation, Protection,
and Management, and Ch. NR 103 - Water Quality Standards for
Wetlands are applicable for this site if treated leachate is
discharged to the wetlands, if any structure is built or any fill
is placed in a wetland area, or if any construction is done in a
shore land area.
Ch. NR 112, WAC, which requires that no drinking water wells be
located within 1,200 feet of a landfill, unless a variance is
obtained from the WDNR, is applicable to the site.
Action-specific ARARs
Action-specific ARARs are requirements that define acceptable
treatment and disposal procedures for hazardous substances.
Federal ARARs
For landfill closure, RCRA Subtitle D is relevant and appropriate
because the majority of the wastes that were placed in the
landfills are low level threat wastes (municipal waste). The
current cap on the landfill does not meet Federal closure
requirements for a solid waste landfill.
For closure of the mercury brine pit, RCRA subtitle C
requirements are relevant and appropriate because the wastes
disposed in the mercury brine pit are RCRA listed waste K071,
mercury brine sludge, and the wastes were disposed in the .mercury
brine pit prior to 1980, the effective date of RCRA. The
subtitle C cap is appropriate because the purpose of closing the
26
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mercury brine pit is to eliminate infiltration into the pit and
achieve long-term effectiveness and permanence of protection of
human health and the environment.
RCRA Land Disposal Restrictions (40 CFR Part 268) are applicable
to any leachate treatment residuals from the landfill if they are
determined to be characteristic RCRA wastes.
Disposal of nonhazardous wastes are regulated under 40 CFR
Part 257 and these requirements are applicable to disposal of
nonhazardous wastes associated with this remedial action.
Treated leachate may be discharged to a POTW, surface water or
wetlands. These discharge points are regulated under 40 CFR
section 403.5, and the National Pollution Discharge Elimination
System (NPDES).
Federal regulations at 40 CFR section 264.310 regarding post-
closure care to ensure that the site is maintained and monitored
are applicable.
state ARARs
Ch. NR 30" Wisconsin statutes, regulates dredging, relocation,
enlargement, grading and structures in or near navigable waters
of the State. These statutes would be applicable for any
structures built in or near the surface water body. Such
structures may be needed for discharge of treated leachate.
The discharge of wastewater (treated leachate) to the land and/or
surface waters; effluent limits; discharge permits;
sampling/testing methods is regulated by Ch. 147, Statutes -
Wastewater Management Programs and Chs. NR 102, 104, 105, 106,
200, 207, 214, 217, 219, 220, WAC Surface Water Discharge
Regulations (WPDES). These requirements are all applicable to
the discharge of treated leachate to the wetlands or surface
water body. These regulations state that no discharge shall
contain quantities of listed pollutants greater than that would
remain after subjecting the water to best available technology
econQmicallyachievable (BATEA). .
Ch. NR 108, WAC, regulates the plan review and standards for
wastewater treatment facilities and Ch. 211, WAC - pretreatment
requirements for discharge to a POTW. These requirements are
applicable to this site if leachate is to be discharged to a
POTW.
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The states' Solid and Hazardous Waste Programs are regulated by
Ch. 144, Statutes. The Solid Waste regulations are Ch. NR 500-
520 WAC. The NR 500 series is applicable at this site.
Ch. NR 504.07, NR 506.08(3), 514.07, 516.07, WAC -
Landfill capping and Closure Requirements are
applicable at this site. This cover system is a
necessary first step to prevent future and abate
current exceedences of the groundwater standards found
, in Ch. NR 140, WAC. Whether or not active groundwater
remediation will be necessary to meet the groundwater
quality standards in Ch. NR 140 will be determined in
the second operable unit ROD.
Ch. NR 508, WAC - Landfill Monitoring Requirements are
applicable to this site for the long-term groundwater
monitoring;
Ch. NR 504. 04 ( 4) (e) & ( f), 506 . 07 ( 3), and 508. 04 ( 2) ,
WAC - These requirements are applicable to this site
for controlling explosive gas migration and levels and
for soil gas monitoring. Ch. NR 506.08, WAC, may be
applicable for this site. This requirement regulates
active gas extraction sy?tems which effectively collect
'and combust the gas.
Ch. NR 506.08(3) (b), WAC - This requirement is
applicable to this site to control stormwater runoff
from the site.
Ch. NR 504.05 is applicable because it provides the
minimum design criteria for all aspects of the remedial
measures.
The Hazardous Waste Regulations are the Ch. NR 600-685, WAC,
series. These requirements are either applicable or relevant and
appropriate for the remedial actions at the site.
Ch. NR 605, WAC - Hazardous Waste Listing and
Identification.
Ch. NR 610, 615, WAC - Standards for Small and Large
Quantity Hazardous Waste Generators.
Ch. NR 620, WAC - Hazardous Waste Transporter Standards
and ,Licensing Requirements.
Ch. NR 630, WAC - Hazardous Waste Storage, Treatment
and Disposal Facility standards.
Ch., NR 635, WAC - Leachate Monitoring Standards and
Corrective Action Requirements.
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Ch. NR 660, WAC - Hazardous Waste Landfill and Surface
Impoundment Standards.
Ch. NR 675, WAC - Land Disposal Restrictions.
CH. NR 685, WAC - Closure and Long-term Care
Requirements.
Ch. NR 400-499, WAC, provides air pollution control standards and
is applicable to this site for any off gases produced by the gas
extraction system and/or waste water treatment system.
Ch. NR 149, WAC, regulates the State's Laboratory certification
Program. This requirement is applicable to any analytical
testing done at the site.
C.
Cost Effectiveness
The first operable unit for this site is cost effective because
it has been determined to provide overall effectiveness
proportional to its costs, the net present worth value being
$4,900,000. Solidification/stabilization of the mercury brine
pit will ensure that leachate in the pit will not pose a threat
to the gro~ndwater in the future, and future generation of
leachate in the pit will be eliminated; therefore the added costs
of the sOlidification/stabilization of the mercury brine pit are
justified given the additional level of protection provided.
utilization of Permanent Solutions and Alternative
Treatment Technologies (or Resource Recovery
Technologies) to the Maximum Extent Practicable
u.S. EPA has determined that the first operable unit represents
the maximum extent to which permanent solutions and treatment
technologies can be utilized for closure of the landfills in a
cost-effective manner for the Spickler Landfill site. u.S. EPA
has determined that this selected remedy for the first operable
unit provides the best balance of tradeoffs in terms of long-term
effectiveness and permanence, reduction in toxicity, mobility, or
volume achieved through treatment, short-term effectiveness,
implementability, cost, also considering the statutory preference
for treatment as a principal element and considering State and
community acceptance.
D.
The selected remedy for the first operable unit will
significantly reduce the inherent hazards posed by the waste mass
and the mercury brine pit by capping the landfills and. mercury
brine pit, solidification/stabilization of the mercury brine pit,
landfill gas control, collection and treatment of leachate and
groundwater monitoring.
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~
E.
Preference for Treatment as a Principal Element
The statutory preference for treatment as a principal element of
a remedy is satisfied by the first operable unit.
The selected remedy for the first operable unit satisfies the
statutory preference for remedies that employ treatment as a
principal element because stabilization of the mercury brine pit
constitutes treatment of the principal threat. Short-term
effectiveness is similar for all the alternatives considered.
All of the alternatives will have similar implementability
problems except the alternatives that require
sOlidification/stabilization of the mercury brine pit.
SOlidification/stabilization of the mercury brine pit could pose
implementation problems, but these will be considered during the
treatability tests.
XI.
DOCUMENTATION OF SIGNIFICANT CHANGES
A significant change has been made in the remedy selected for the
Spickler Landfill site since the publication of the FS and the
Proposed Plan in December 1991. The remedy recommended in the
Proposed Plan was Alternative 5: Fencing and Deed Restrictions;
NR 504 cap on the landfill; sOlidification/stabilization and
capping with an NR 660 cap of the mercury brine pit; active
landfill gas control; leachate collection and treatment; and
groundwater pump and treat. Since publishing the proposed plan,
u.S. EPA has determined that an operable unit approach is more
appropriate for this site than one final remedy at this time.
u.S. EPA has determined that the first operable unit, which is
addressed by this ROD, will consist of
sOlidification/stabilization and capping of the mercury brine pit
and capping the landfill, landfill gas control, leachate
extraction and treatment, and groundwater monitoring. The second
operable unit will consist of a final remedy decision for
groundwater. The Agency has determined that the operable unit
approach is more appropriate at this time because it allows a
more focused, logical approach, whereby the landfill, which is
the source of groundwater contamination, is remediated first.
SOlidification/stabilization and capping of the mercury brine pit
in conjunction with leachate extraction and a solid waste cap on
the landfill, may improve groundwater quality. The observation
and analysis, including groundwater monitoring, of the effects of
these control measures on the landfill and mercury brine pit are
needed to allow for an informed decision on a final remedy
decision for groundwater.
The remedy selected for the first operable unit is Alternative 4:
fencing and deed restrictions; NR 504 cap on the landfill;
solidify/stabilize the mercury brine pit and cap it with an NR
660 cap; active landfill gas control; leachate collection and
30
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treatment and groundwater monitoring. This change in remedy
selection, to an operable unit approach, is a logical outgrowth
based on the information available during the public comment
period and the comments submitted. Among the four alternatives
considered for this first operable unit, Alternative 4 has been
determined to provide the most appropriate balance of tradeoffs
among the alternatives, with respect to the nine criteria.
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