United States Off ice of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R07-91/049
September 1991
Superfund
Record of Decision:
Hastings Groundwater
Contamination
(Operable Unit 10), NE
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50272-101
REPORT DOCUMENTATION 11. REPORT NO..
PAGE EPA/ROD/R07-91/049
l ~
3. RecIpient'. Acce88lon No.
... Thl81nd SubtItI8
SUPERFUND RECORD OF DECISION
Hastings Groundwater Contamination
Seventh Remedial Action
7. AuthM(.)
5. Report Datil
09/30/91
(Operable Unit 10), NE
8.
8. Performing Organization Rept. No.
8. P8rfonnIng OrgairUatlon Name and Addre..
10. ProjectlT.8kJWork Unit No.
11. Contr8Ct(C) or GI'8III(G) No.
(C)
1~ Spon8oItng Org8nlz81lon Name and Add-
U.S. Environmental Protection
401 M Street, S.W.
Washington, D.C. 20460
(G)
13. Type of Report . PerIod Covered
Agency
800/000
14.
15. Suppl8m8nt8ry Not88
16. Abalr8ct (UmIt: 200 w0rd8)
The Hastings Groundwater Contamination site consists of localized areas where an
aquifer is contaminated with industrial chemicals in or near the City of Hastings,
Adams County, Nebraska. Both the source control operable unit 10 (OU10) and ground
water operable unit (OU2) of the North Landfill, a 13.4-acre former municipal
landfill, are addressed by this ROD. Land use near the landfill is mixed
residential and commercial with an active railroad directly north of the site. The
estimated 23,000 residents of Hastings obtain their drinking water from the
municipal water system, which taps into the underlying sole-source aquifer. As
early as 1938, brickmakers obtained clay source materials from the area of the
landfill. From 1961 to 1964, the City of Hastings operated a municipal landfill
onsite and accepted municipal and industrial wastes including wastes containing
VOCs. The landfill was initially capped, and later in the 1970's an additional two
feet of capping materials were added. In 1983, ground water contamination was
discovered when the State sampled the Hastings public water supply system in
response to citizen complaints about water quality. EPA investigations have
identified VOCs including benzene, TCE, DCE, and vinyl chloride in the ground water
(See Attached Page)
17. Documant An.Iy8I. L DeKriptora
Record of Decision - Hastings Groundwater Contamination (Operable Unit 10), NE
Seventh Remedial Action
Contaminated Media: soil, gw
Key Contaminants: VOCs (cis 2-DCE, trans 1,2-DCE, PCE, TCE, vinyl chloride)
b. 1d8n1I1I8r8I0pen-EncIed Tenn.
c. COSATI R8IdIGroup
18. Avall.blilty Statement
18. SecurIty CI... (Thi. Report)
None
20. Security CI- (Thi. P.ge)
None
21. No. 01 P.ge.
43
22. Prlca
S88 ANSI-Z38.18
See IMl1UClioM on RlI".,..
(Form8rIy NTlS-35)
Department 01 Comm8n:8
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EPA/ROD/R07-91/049
Hastings Groundwater Contamination (Operable Unit 10), NE
Seventh Remedial Action
Abstract (Continued)
adjacent to and downgradient from the site. In 1985, soil-gas samples indicated that
the vadose zone above the aquifer was contaminated. This ROD provides an interim
remedy for both OUs. Future RODs may address additional source control measures,
subsurface monitoring, ground water extraction and treatment, wellhead protection and
treatment, and provision of institutional controls. The primary contaminants of
concern affecting the soil and ground water are VOCs including TCE, DCE, and vinyl
chloride.
The selected remedial action for this interim remedy includes geotechnical testing of
the existing landfill cap, improving the present cap through regrading to promote
surface run-off, and revegetating the landfill surface; pumping and onsite treatment of
contaminated ground water with a technology to be determined after further testing, .but
will be either air stripping or UV oxidation; monitoring the vadose zone, saturated
zones, and ground water; and implementing institutional controls including deed
restrictions, and site access restrictions such as fencing. The estimated present
worth cost for this remedial action will range from $2,300,000 to $4,000,000, based on
ground water treatment and discharge options.
PERFORMANCE STANDARDS OR GOALS: Chemical-specific ground water clean-up goals are
based on SDWA MCLs, and include TCE 5 ug/l, cis 2-DCE 70 ug/l, trans 1,2-DCE 100 ug/l,
and vinyl chloride 2 ug/l.
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INTERIM ACfION RECORD OF DECISION
DECLARATION
SITE NAME AND LOCATION
North Landfill Subsite, Source Control Operable Unit
North Landfill Subsite, Ground Water Operable Unit
Hastings Ground Water Contamination Site 0- (). ./ 0
Hastings, Nebraska
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected interiin remedial actions for the Nonh
Landfill for the subsite source control and ground water operable units. The North
Landfill subsite is a subsite of the Hastings Ground Water Contamination Site, Hastings,
Nebraska. These actions were chosen in accordance with the Comprehensive
Environmental Response, Compensation and Liability Act of 1980 (CERCLA), as
amended by the Superfund Amendments and Re-authorization Act of 1986 (SARA),
and, to the extent practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP). This decision is based on the administrative record for this
subsite. .
The State of Nebraska concurs with the selected remedies as interim actions for this
subsite. ,
ASSESSME1\'7 OF THE SITE
Actual or thr~atened releases of hazardous substances from this subsite, if not addressed
by implementing the response actions selected in this interim action Record of Dec..:iOIi
(ROD), may present an imminent and substantial endangerment to public health,
welfare, or the environment.
DESCRIPTION OF THE SELECTED INTERIM REMEDIES
This interim action Record of Decision contains elements which address both the source
control and ground water operable units. Tbe interim source control remedy was
developed to protect public health, welfare and the environment by substantially
reducing migration of vadose zone contaminants -(contaminants in the unsaturated soil
overlying the aquifer) to the aquifer. The interim ground water remedy also was
developed to protect public health, welfare and the environment by controlling the
migration and reducing the volume and mass of contaminants present in the ground
water beneath and downgradient from the North 4ndfill. Both~perable unit interim
actions will be consistent with all planned future remedial activities. Subsequent ROD(s)
will address further actions to be taken at the Nqrth Landfill in support of either an
interim or a final remedy. .
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. .
The major components of the selected remedies include:
.
Landfill Surface: The existing cap will undergo geotechnical testing and
will be improved as necessary, based on the testing results. Cap
improvements will include regrading and revegetating the landfill surface.
A fence will be installed to control site access. Deed restrictions will be
imposed to restrict land use, including farming. Subsurface monitoring of
the vadose zone at the boundary of the North Landfill will be conducted to
assess surface cap effectiveness in reducing the migration of volatiles into
the aquifer.
Ground Water: A pump test will be conducted to support design of a
groundwater extraction and treatment system. The system will be designed
to actively control migration of ground water contaminated with volatile
organic compounds and to rapidly remove contaminant mass from the
aquifer. Monitoring wells will be installed and ground water sampling and
analysis will be conducted to observe the effectiveness and progress of the
remediation system.
.
STATUTORY DETERMINATIONS
These interim actions are protective of public health, welfare and the environment. The
actions comply with action-specific and some chemical-specific Federal and State
applicable or relevant and appropriate requirements and are cost-effective. Although
these interim actions are not intended to fully address the statutory mandate for
permanence and treatment to the maximum extent practicable, these interim actions
utilize treatment and thus are in furtherance of that statutory mandate. Because these
actions do not constitute a final remedy for the subsite, the statutory preference for
remedies that employ treatment that reduces toxicity, mobility, or volume as a principal.
element,. although partially addressed in tbese remedies, will be addressed by tbe final
response action. Subsequent actions are planned to address fully tbe tbreats posed by
the conditions at this subsite. Because tbese interim remedies will result in hazardous
substances remaining on site above health-based levels, a review will be conducted to
ensure that these remedies continue to provide adequate protection of human health and
the environment within five (5) years after commencement of tbe remedial action.
Review of this subsite and of tbese remedies will be ongoing as EPA continues to
develop remedial alternatives for the North Landfill SUbSi...? / J .
9- "0 - <]1 . ~/~,/. A,p-V
. ~ . ~
~e ~~ y
Regional Administrator
Region vn
Attachments:
-
,
Decision Summary
Responsiveness Summary
Administrative Record Index
2
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INTE~M ACTION RECORD OF DECISION
DECISION SUMMARY
HASTINGS GROUND WATER CONTAMINATION SITE
NORTH LANDFILL SUBSITE
HASTINGS, NEBRASKA
Prepared by:
u.S. Emironmental ProteCtion Agency
Region VII
Kansas City, Kansas
September 30, 1991
3
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Section
I.
II.
III.
IV.
V.
VI.
VII.
Interim Record of Decision
Decision Summary
Contents
~
Site Description. . . . . . . . ,... . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Site History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 .
Enforcement History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Community Relations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Scope and Role of Operable Unit. . . . . . . . . . . . . . . . . . . . . . 4
Si te Characteristics. . . . . . . . . . ~ . . . . . . . . . . . . . . . . . . . . . . 5
Summary of Site Risks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~
VIII. Description of Alternatives. . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
IX.
X.
XI.
XII.
Summary of Comparative Analysis of Alternatives. . . . . . . . . . 12
, . .
Selected Remedies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Statutory Determinations. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 20
Documentation of Significant Changes. . . . . . . . . . . . . . . . . . . 21
1
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Decision Summary
Contents
List of Tables:
1. Summary of Soil-Gas Data
2.
Regional Stratigraphy of Hastings Area
3.
SUII1Llary of Ground Water Data for On-Site Wells
4a.
Target Concentrations for Potential Carcinogenic Chemicals Detected in
Ground Water
4b.
Target Concentrations for Potential Non-Carcinogenic Chemicals Detected
in Ground Water -
5.
Comparative Analysis of Alternatives
6.
Estimated Costs of the Selected Remedies
7.
Action-Specific State Rules and Regulations
List of Figures:
1. Hastings Ground Water Contamination Site
2.
,
,
Area Land Use
3.;
Cross Section Showing Fill
4.
WelJ Locations, North Landfill subsite
5.
Soil Boring Locations
6.
Trichloroethylene Chemical Concentrations in Soil-Gas Versus Depth
7.
Simplified -Cross Section of Area
TCE Plume Based on Mean 1989 Concentrations
8.
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.l-
n
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DECISION SUMMARY
NORm: LANDFILL SUBSITE
HASTINGS GROUND WATER C01\"TAMINATION SITE
SITE DESCRIPTION
The Hastings Ground Water Contamination Site is located in Adams County,
Nebraska. The City of Hasti!~gs operated the North.Landfill from 1961 through 1964.
Landfill operations ceased in 1964 and since that time, the landfill property has been
used for farming.
The Hastings Ground Water Contamination Site consists of an aquifer
contaminated with industrial chemicals, primarily chlorinated volatile organics.
Contamination was discovered in 1983 when the Nebraska Department of Health
(NDOH) sampled the Hastings public water supply system in response to citizen
complaints of foul taste and odor in the drinking water. That same year, NDOH and the
Nebraska Department of Environmental Control (NDEC) began investigating wide-
spread ground water contamination in the Hastings area. The city, which has a
population of approximately 23,000, obtains all of its drinking water supply from the
public water supply system which taps the ground water aquifer, known as the High
Plains Aquifer from the Pleistocene period. The contamination problems addressed by
this interim ROD pertain to this aquifer.
The North Landfill subsite is one of several subsites that make up the Hastings
Ground Water Contamination Site in Hastings, Nebraska (Figure 1). The subsite is
located just east of the city limits of Hastings, Nebraska and occupies approximately 13.4
acres. The U.S. Land Office designation for the North Landfill is the SW 1/4, SE 1/4,
Section 8, Township 7 North, Range 9 West. The landfill surface topography is relatively
flat, and the approximate elevation is 1910 feet above mean sea level. The subsite is
bounded on the north by the Burlington Northern Railroad, with a trailer park directly
north of the railroad tracks, residential and commercial properties directly to the west,
U.S. Highway 6 and several commercial properties to the south, and several commercial
properties to the east. Figure 2 shows adjacent land use near the North Landfill.
SITE HISTORY
As early as 1938, local brickmakers obtained clay materials from the land which is
known today as the North Landfill. The clay was removed unevenly to a depth of 40
feet. In 1961, the Edwards family leased the property to the City of Hastings to operate
a municipal landfill. This landfill was iri operation from August 1961 through 1964 under
a State permit and accepted variety of wastes, including wastes containing volatile
organics. According to a former landfill employee, municipal wastes as well as industrial
wastes were added to the landfill from the west to the east. In the west, the fill, mainly
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consisting of construction rubble, was added to a deptb of approximately 10 feet. In the
southeast section of tbe landfill, deposits reached a depth of approximately 40 feet. The
U.S. Environmental Protection Agency's (EPA) investigation focused in the deeper fill
areas. Figure 3 shows the depth of fill in the southeast section of tbe landfill. When the
landfill was closed, a lo-foot layer of clay and silt containing bricks and wood chips was
used to "cap" or cover the landfill. In the later 1970's a second 2-foot layer of clay soil
was placed on top of tbe original. cover to fill in depressions which had formed due to
differential settling. The North Landfill is fenced on the north side and on a portion of
the east side but is otherwise completely accessible. The surface of the North Landfill is
currently being farmed for alfalfa. There are no buildings or other structures on the
subsite.
The City of Hastings Municipal Well No. 12 (M-12) is located near and
upgradient of tbe North Landfill. This well was decommissioned in April 1983 due to
trichloroethylene (TCE) contamination. No other municipal wells are located within a
half mile radius of the landfill. A second public water supply system, run by Community
Municipal Services, Inc. (CMS), supplies customers east of the city limits of Hastings.
Two of the three CMS system supply wells, all located downgradient from the North
Landfill, have been decommissioned due to contamination. .
EP A has been investigating sources of ground water contamination in the
Hastings area since 1984. Due to the high levels of VOCs found in three municipal
wells, EP A designated the contaminated area as the Hastings Ground Water
Contamination Site and placed it on the National Priorities List in 1986. Tbe National
. Prioriti~List is a (1ationwide list of hazardous waste sites that are. eligible for
investigation and remediation under the Superfund Program.
EPA installed ground water monitoring wells at the subsite from 1986 to 1989.
Figure 4 illustrates the location of all subsite monitoring wells. During this period and to
the present, EP A has been collecting ground water samples from ~he contaminated'
aquifer. As more fully set forth in the Remedial Investigation Report with Addendum
and the Feasibility Study Report, the subsurface and the ground water at the subsite are
contaminated with volatile organic compounds (VOCS), including but not limited to, .
TCE, dichloroethene (DCE), vinyl chloride (VC), and benzene. VOCs are organic
compounds that evaporate readily at room temperature. TCE was used as a degreasing
solvent by metal finishing industries, as well as other industries. DCE and VC are
biological breakdown products of TCE. Benzene is a component of gasoline and was.
used as a general purpose solvent. .
EP A conducted its first soil-gas investigation at the North Landfill in 1985. In
1986 and 1988, further investigations were conducted to identify and characterize the
extent of VOC contamination within the North Landfill vadose zone. Figure 5 shows the
areas where samples were collected during the 1986 and 1988 inyestigations. Borings
DOOS, DOll, D012, and D013 were deep borings (greater than 120 feet deep). Figure 6
shows the levels of TCE found in the soil-gas sa~ples collected from these borings.
Analyses of soil-gas samples were used to identify and define areas for further'
investigation. An investigation, conducted in 1990, focused on the presence of VC in
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the shallow (less than 28 feet deep) portion of the landfill. The data indicate that wastes
buried in the North Landfill have contaminated and may continue to contaminate the
ground water beneath and downgradient of the subsite and that the soil-gas within the
vadose zone also is contaminated. .
All data results are presented in the Remedial Investigation (RI) Report which
was released on January 4, 1991. An Addendum to the RI was prepared by EP A which
states that the contamination found in the soil-gas is indicative of vadose zone
contamination. This Addendum was released in February, 1991. A draft Feasibility .
Study, based on the RI Report and Addendum to the RI, was released April 4, 1991. A
revised Feasibility Study was submitted by the City to EP A on July 23, 1991 and is in
review. A Proposed Plan explaining the preferred alternative to mitigate the
contamination at the subsite was released June 25, 1991. A Public Comment period was
held from June 25 to August 23, 1991 to receive comments from any interested party on
the Proposed Plan and other subsite documents.
ENFORCEMENT HISTORY
Potentially Responsible Parties (PRPs) are those individuals or corporations liable
for the cpsts .incurred by the EP A for investigation and cleanup of contamination at a
Superfund site. In 1985, EP A conducted a PRP search and in September 1985, general
notice letters were issued to the following identified PRPs: Bruce Edwards, as owner of
the landfill property; the City of Hastings, as operator; Dutton-Lainson Company, and
Dravo Corporation (successor corporation to Hastings Industries, Inc.), as generators
who disposed of hazardous substances at the subsite. In 1991, after further research, a
general notice letter was issued to Bernice Edwards, as owner, and the U.S. Navy, as a
generator who disposed of hazardous substances at the subsite.
In January 1987, EPA met with parties who at the time had been noticed at the.
North Landfill subsite and invited them to make proposals to EPA to undertake the
Remedial Investigation and the Feasibility Study (RIfFS). None of the PRPs made an
offer at that time. Almost two years later, after EP A had commenced the remedial
investigation, the City came forward and offered to complete the RI and perform the FS.
On September 26, 1989 EPA and the City of Hastings entered into an Administrative
Order on Consent (AOC) pursuant to Section 104 and 122 of CERCLA for the
completion of the Remedial Investigation (RI) and performance of the Feasibility Study
(FS) at the North Landf1l1. Pursuant to the requirements Qf the AOC, the City prepared..
a RI report and FS report. EP A added an Addendum to the RI report which states that
the vadose zone is contaminated and a source control option must be evaluated.
COMMUNITY RELATIONS
Community relations activities for tbe Hastings Ground Water Contamination Site
were initiated by EPA in 1984. Early community relations activities included meeting
with City and State officials to discuss- the Site (December 1984), conducting interviews
with local officials and interested residents (February 1985), establishing an information
repository (February 1985), and preparing a Community Relations Plan (October 1985).
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Since December of 1984, EPA has conducted periodic meetings with Hastings city
officials to update them regarding site work, investigation findings, and most recently, in
August 1991, to hear the City's concerns about EPA's Proposed Plan. The Community
Relations Plan was revised in January 1988 and again in January 1990 to reflect new
community concerns and site activities.
Information on the North Landfill subsite, in the form of fact sheets, has been
mailed to public officials, Hastings' businesses, and numerous citizens. EPA held a
public comment period from June 25 to August 23, 1991 following the release of the
Proposed Plan (June 25, 1991). The Proposed Plan identified the preferred alternative
to mitigate the contamination at the North Landfill subsite. On July 18, 1991, EPA held
a public meeting to discuss the preferred alternative for the subsite and to receive
citizens' comments and questions. Agency responses to these comments are included in.
the Responsiveness Summary attached to this Decision Summary.
SCOPE AND ROLE OF OPERABLE UNITS
This interim action ROD addresses activities which will mitigate contaminant
migration from the source control operable unit and ground water operable unit in the
vicinity of the North Landfill and will reduce contaminant mass in the ground water.
The ground water contamination is considered the principal threat to human health and
the environment. The purpose of the interim action for the source control operable unit
is to prevent the infiltration of surface water through the landfill by improvements to the
landfill cap. The purpose of the interim action for the ground water operable unit is to
begin aquifer restoration and collect additional information on the aquifer's response to
remediation. Information collected during implementation also will be used to evaluate
aquifer response to remediation.
This ROD is consistent, to the extent practicable, with the National Oil and
Hazardous Substances Pollution Contingency Plan (NCP). According to the NCP, the
EP A regulation which establishes procedures for the selection of response actions, an
interim action is appropriate where a contamination problem will become worse if left
unaddressed and where the interim action will not be inconsistent with a final remedial
action. Consistent with the principles of the NCP, these remedial actions are designed to
promptly initiate a remedial action response which should prevent further degradation of
the aquifer and will rapidly reduce. contaminant mass. In accordance with the NCP, the.
interim actions for the North Landfill subsite will complement and be consistent, to the
extent possible, with the final remedy for the subsite. The final remedy may include
additional source control measures including soil vapor extraction, subsurface monitoring,
ground water extraction and treatment options, well head protection and treatment, and
institutional controls. Any future actions will be considered and selected based on the
requirements of the NCP and remedy selection process as described therein. Because a
final remedial action will follow these interim actions, these interim actions need not
meet an Federal and State standards for clean-up of the aquifer, nor must they provide a
permanent solution to the contamination problems. Prompt remedial response is
necessitated because water supply wells in the proximity of the North Landfill that
. .
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remain in use have been affected and will continue to be affected by the contaminated
ground water emanating from, the North Landfill, unless these actions are taken.
The interim actions to be conducted at all of the subsites which are part of the
Hastings Ground Water Contamination Site will have a common goal to contain and
remove contaminants in the ground water and reduce cancer risk levels to correspond to
no more than an estimated one additional cancer case in a population of 10,000 based
on an assumed 30-year exposure period. Additional goals for the North Landfill subsite
. interim action include prevention of-further ground water quality degradation by
eliminating further leaching of contaminants into the ground water via infiltration of ,
surface water through the landfill contents.
Steps have been taken to prevent human exposure to contaminated ground water
in the North Landfill area. However, unrestricted water use, though it is not known to
be occurring, would pose an immediate threat to human health. Testing results from
samples collected during EP A's on-going investigations are supplied to the City and the
Nebraska Department of Health (NDOH). If future sampling indicates the chemicals
have migrated to other public water supply wells, the NDOH, which has been delegated
authority under the Safe Drinking Water Act (SDW A), can cause the public water
supplier to provide water which meets the requirements of the SDW A As previously
stated, the CMS currently is ~omprised of a single welJ with no additional provisions for
an alternate water supply. This system wi~l be compromised should this well become
contaminated. Data in the Remedial Investigation report indicate that an interim action
is appropriate to prevent further degradation of the aquifer.
" .
SITE CHARACTERISTICS
For remediation, the North Landfill has been divided into two separate operable
units, a source control operable unit and a ground water operable unit. The source
control operable unit includes the landfill surface and the vadose ~one.. The ground
water operable unit includes the ground water beneath the subsite. Figure 7 shows a
cross section of the North Landfill area.
Surface Characteristics
The following current conditions of the landfill surface make the existing cap an
ineffective barrier for surface infiltration: .
.
Composition of the initial cap: The initial cover, installed in 1964, was a
heterogeneous mix of clay, silt, wood and brick. Problems of surface
subsidence were immediately noticed and, in 1977, an additional 2-foot
clay cap was added. This additional clay cap was also ineffective in
preventing further problems of subsidence and the formation of surface
depressions which tended to pond with rain water.
.
Land use: Further enhancement of the infiltration rate of surface water
into the active fill area probably has occurred, depending on the crops
..
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intentionally and unintentionally raised on the laildfill. Crops with
extensive root systems will penetrate the clay cap and allow the channeling
which will result in a net increase in the vertical permeabilities through the
cap. Infiltration of surface water exacerbate both subsidence and leachate
formation.
.
Climate conditions: Hastings is located in a semi.arid climate and the
annual cultivation and harvesting activities would disrupt surface soils and
violate the integrity of any existing cap. Differential settlement and
subsequent poor drainage has resulted in the ponding of surface water on
the landfill cap. Pools of water will provide a driving force for infiltration
of surface water into and through the landfilled material. Leachate
generated by the introduction of surface water into the body of the unlined
landfill will migrate through the underlying vadose zone and into the
Pleistocene aquifer.
.
Access: Current conditions at the landfill allow unrestricted access to this
subsite.
Soil.Gas and Soil Characteristics
Soil.gas investigations conducted by EPA during 1986.1989 indicate vadose zone
contamination. TCE and other volatile organic compounds were found to be present at
significant concentrations. Refer to Figure 6 for levels of TCE found within the soil-gas
boring samples.
The following contaminants were found in soil at low levels: xylene, benzene,
toluene, 'ethyl benzene, polychlorinated biphenyls, and a breakdown product of the
pesticide .DDT (4,4'.DDD). Based on the soil and soil.gas sample results, EPA
concluded that contamination is present within the unsaturated zone. Table 1 is a
summary of the soil-gas analytical results. The samples collected in 1989 were from the
deep zone (less than 120 feet deep). The samples colJected in 1988 and 1990 were from
the fill area.
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,
Ground Water Characteristics
The geologic profile (see Table 2) in tbe Hastings area, from shallowest to
deepest deposits of interest, are Quaternary fl!lvial deposits and Cretaceous marine
deposits. Pleistocene deposits make up the majority of tbe regional unconSolidated.
deposits and contain the aquifer that supplies the Hastings area. The upper geologic
units of the Pleistocene deposits,' the Peoria, Loveland and Sappa Formations are finely
grained loesses and sandy clays with some sandy lenses. The total thickness of the upper
fine grained Pleistocene materials is approximately.50 to 100 feeT. The lower PICfistocene
deposits consist of fine to coarse sand and gravel with discontinuous layers of silts and
days. These water.bearing deposits are approximately 100 feet thick. The Cretaceous
Niobrara Formation, a marine sbale with frequent chalky zones, is considered to be
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bedrock in the Hastings area. The contact between the Pleistocene and Cretaceous
formations is a weathered and eroded surface.
The Pleistocene age ground water aquifer is a prolific ground water resource
capable of sustaining substantial pump rates of 1000 to 2000 gallons per minute. The
regional potentiometric surface slopes toward the east-southeast with a gradient of
approximately 0.001 ft/ft to 0.002 ft/ft. Although there are some minor differences
between the upper and lower portions of the aquifer, available information indicates that
it behaves as a single unconfined aquifer. The transmissivity of the aquifer ranges from
90,000 gallons per day per foot (gpd/ft) to 225,000 gpd/ft. The hydraulic conductivi~ for
thp. aquifer ranged from 989 gallons per day per square foot (gpd/ft2) to 2184 gpd/ft .
The aquifer is recharged by infiltration of precipitation, seepage from streams, and
inflow from irrigation to the extent of approximately 1.6 inches per year.
Remedial investigation results have indicated there are sources of contamination
in the vadose zone and in the ground water beneath the North Landfill and
downgradient of the landfill. During landfill operations, wastes containing VOCs,
including chlorinated solvents, were disposed in the landIDl. These VOCs have since
migrated vertically into the deeper vadose zone and have entered the aquifer. Once the
VOCs entered the aquifer, they migrated downgradient primarily in the dominant
direction of flow (east-southeast).
Precise ground water plume characterization is made difficult by the fact that the
Pleistocene aquifer is highly transmissive and is heavily used. Seasonal stress on the
aquifer alters the hydraulic flow patterns in the region substantially; consequently,
contaminant concentrations vary seasonally. The present monitoring network is
insufficient to fully characterize the extent of the plume but is adequate to establish
primary contaminant plume features.
During EP A's investigation, in-situ water samples were collected from each of the
deep borings. The following contaminants were found in these water samples: 1,2-DCE,
tetrachloroethene (PCE), 1,1,1-trichloroethane (l,l,l-TCA), TCE, and vinyl chloride
(VC).
Data from the following monitoring and production wells depicted in Figure 4
were used to characterize and evaluate the North Landfill: DW-1, MW-5, MW-6, MW-
7; MW-17 (MW-53), MW-19 (MW-50), MW-21 (MW-54), ldW-24, MW-25 (MW-52),
MW-26, OW-IS & -ID, OW-2S & -2D, and M-12. These wells are shown on Figure 4.
The public water supply well, M-12, was installed in the late 1950's before EPA's
investigation of Hastings began. State observation wells, OW-series, were installed in
November 1984. Wells MW-5, -6, and -7 were installed in June 1986. Wells MW-17, -
19, -21, and -25 were installed in April 1988. Well MW-26 was installed in July 1988.
Analyses of samples collected from tbese wells indicate high levels of TCE, DCE, and
VC in the ground water ranging from 1300 - 2300 ug/l, 1300 - 2000 ug/l, and the
detection limit to 87 ug/l, respectively. Tbese compounds were found to be the
characteristic compounds of the contamination present beneath the North Landfill and
the plume downgradient from this location. Although TCE is found at other subsites at
7
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the Hastings Ground Water Contamination Site, substantial concentrations of 1,2 DCE
and YC, anaerobic degradation products of TCE, are only found in association with the
North Landfill subsite. Table 3 is a summary of the ground water data colJected from
su bsite wells.
The primary contaminants of concern found beneath the landfill and in the
ground water are: benzene; 1,2-dic;..hloroethane (1,2-DCA), l,l-DCE, 1,2-DCE, PeE,
l,l,l-TCA. TCE, and YC. All are members of the YOC family and as YOCS they
readily form vapors because they have low boiling points. These vapors have a tendency
to move through soil pore spaces driven by diffusive and dispersive processes. Further,
gravitational fo"ces tend to drive vapors and liquids in a downward vertical direction
untiJ they meet ground water. YOCs may then become dissolved in ground water or
may be transported in a separate phase if concentrations are great enough.
The volume of ground water affected by VOCs which migrated from the North
LandfilJ is difficult to calculate. Substantial aquifer heterogeneity, a limited monitoring
network, and seasonal stress on the aquifer make accurate plume volume estimates
difficult. However. for the purposes of developing this interim ROD, such estimates
have been made. Figure 8 illustrates the plume concentration area utilized for these
calculations. The aquifer was estimated to be approximately 100 feet deep and
contaminants were assumed to be present in 30 feet of the aquifer. The volume of
contaminated aquifer is approximately 11.3 million cubic feet. This equates to 84 million
gallons of contaminated water (assuming 0.28 porosity). This represents an estimate of
- the volu~e of wat~r contaminated with more than 500 ug/l of TCE only.
SUMMARY OF SITE RISKS
Superfund requires EP A to seek permanent solutions to protect human health and
the environment from hazardous substances. These solutions provide for removal.
treatment. or containment of dangerous chemicals so that any remaining contamination
does not pose an unacceptable health risk to anyone who might come into contact with
them.
EP A also has evaluated potential risks to human health posed by ground water
contamination if no remedial action were taken. The Baseline Risk Assessment is based
on the results of the contamination studies and evaluates potential carcinogenic and non-
carcinogenic risks. In preparing the Baseline Risk Assessment, EP A first determined the
most likely ways in which community members might come into contact with site-related
chemicals. EP A determined that residents living near the North Landfill subsite might
be exposed to contaminants in ground water if they drink ground water, come into direct
contact with the ground water while bathing. or inhale ground water vapors while
showering. EP A concluded that thre~ chemicals in the ground water at the North
Landfill subsite might pose an unacceptable cancer-risk to residents who use the ground
water. These chemkals are: YC, TCE and DCE. 'These interim remedial actions will
focus on reducing the risk to human health and tbe environment that results frQm
exposure to these chemicals. ,-
8
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EP A considers exposure to a chemical an unacceptable cancer risk if it leads to
more than one additional case of cancer for every 10,000 (10-4) people exposed to it over
a 30-year period. The term "cancer risk" sometimes is referred to as "excess cancer risk"
because it is the number of additional cases above the average number of cases that are
expected to occur in the general population if the chemicals are not present. EP A's
assessment determined that exposure to these contaminants (TCE, DCE, and VC) might
lead to between two additional cancer cases per 10,000 (10-4), and two (2) additional
cancer cases per 1,000 (10-3) people. The fact that these risk levels are unacceptable has
prompted EP A to consider interim actions to rapidly reduce the risk levels while
additional remedial action alternatives are being developed. Tables 4a and 4b illustrate
the various risk level concf'!1trations for the contaminants of concern.
In addition to estimating potential carcinogenic health effects, the Risk
Assessment evaluated potential non-carcinogenic health effects caused by site-related
chemicals. Non-carcinogenic health effects are based upon contaminant concentrations
and are given a Hazard Index Rating (In). Compounds with In ratings greater than or
. equal to one would pose a health risk whereas those less than one would not pose a
health risk (see Table 4b).
The majority of risks associated with ground water at the North Landf1l1 subsite are
based upon the presence and concentrations of TCE, DCE, and VC. The results from
monitoring well MW-6 were used to characterize the risk associated with this
subsite.These contaminants are further described below:
.
VC is mutagenic and carcinogenic. It is classified as a known human
carcinogen (Group A) by EP A VC can enter the body through inhalation
of vapors or ingestion of contaminated food or water. Acute exposure to
VC may cause central nervous system depression. Chronic effects include
loss of bone from fingers and toes, circulatory disturbances and adverse
effects on the skin, blood, lung, and liver. Angiosarcoma of the liver has
been associated with occupational exposure to VC.
.
EPA has classified TCE as a probable human carcinogen (Group B-2).
Acute exposure to TCE may cause headaches, vertigo, visual disturbance,
tremors, nausea, vomiting, eye irritation, dermatitis, cardiac arrhythmias,
and paresthesia. Chronic exposure may irreversibly damage the respiratory
system, heart, liver, kidneys, and central nervous system.
.
.
EPA has not classified DCE (cis and trans) as a human carcinogen (Group
D). Acute exposure to DCE will have similar effects as acute exposure to'
TCE.
Pursuant to the authority of the Safe Drinking Water Act, SDWA, 42 U.S.c.
Section 300(g), EPA has established a Maximum Contaminant Level (MCL) for TCE,
DCE, and VC. The MCL refers to the maximum permissible level of a contaminant in
water which is delivered to any user of a public water system. MCLs are based on
health risk, treatment technology, cost, and analytical methods and are used in
9
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developing ground water cleanup levels. Tbe MCL established for TCE is 5 parts per'
billion (Ppb); tbe MCL for cis 1,2-DCE is 70 ppb; for trans 1,2-DCE is 100 ppb; and tbe
MCL for VC is 2 ppb. Tbe ground water aquifer beneatb the North Landfill bas
concentrations of tbese contaminants far above these MCLs. For a more detailed
description of risk to buman bealth and the environment, refer to the Baseline Risk
Assessment which is contained in the administrative record.
DESCRIPTION OF ALTERNATIVES
As presented in tbe Feasibility StJdy, the remedial alternatives fall into four (4)
general categories. These are: No Action, limited Action, Ground Water Treatment,
and Source Control. Estimated costs for the alternatives are presented in the Feasibility
Study. These cost estimates were based on .what they would cost today to build (Capital
Cost), what they would cost to operate and maintain until the remedial actions are
completed (Annual Operation and Maintenance), and Present Net Worth. Present Net
Worth is the amount'of money that, if invested today at the present interest rate, would
pay for the capital and operating and main~enance costs for the life of the project.
These alternatives are briefly described below.
No Action
Under the no action alternative, tbe subsite would remain in its present condition.
The potential for exposure of the community to contaminant levels exceeding health
standards still would exist. EP A policy requires consideration of a no action alternative
to serve as a basis against which the other remedial alternatives can be compared.
The cost for this alternative is zero; implementation time is zero.
Chemical-specific ARARs would not be met. Action-specific and Location-
specific ARARs do ,not apply to tbis No Action alternative at the North Landfill subsite.
Limited Action
Under the Limited Action alternative, limited cap improvements, access
restrictions, and ground water monitoring would be combined to address the remedial
action objectives of protection of human health and tbe environment. At the North .
Landfill subsite, the access restriction would be implemented to limit future development
and any domestic use of the ground water beneath the subsite. In addition, a security
fence would be instal1ed around the subsite to prevent entry to the subsite. This
alternative does not address the contaminated ground water.
The estimate.d cost for this action is 5560,000 for the Capital Costs and the O&M
for 30 years.
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. Cbezmca1-specific ARARs would not be met. Action-specific and Location-
specific ARARs do not apply to this Limited Action alternative at tbe North Landfill
subsite. .
Ground Water Treatment
Tbe various technologies for treatment of ground water were assembled in
different combinations and analyzea' according to EP A's detailed evaluation critena.
Ground water treatment refers to the remedial technologies that restore the ground
water to a level tbat allows for its beneficial use, sucb as drinking water. The ground
water treatment alternatives considered were:
1.
Ground Water Recovery & Air Stripping/Reinjection
2.
Ground Water Recovery & Air Stripping/Reuse
3.
Ground Water Recovery & Ultraviolet/Oxidation/Reinjection and
Reuse
Under each ground water treatment tecbnology, extraction wells would be
installed and tbe ground water would be pumped to tbe surface in order-to hydraulically
contain the affected ground water that equals and/or exceeds health based levels of 10-4.
A subsite-specific pump test would be conducted to determine the appropriate extraction
rate of ground water for plume containment and mass removal. Once the pump rate
- were det~mined, the need for air emission controls would be evaluated. AIl air
emission alternatives to be evaluated for air emission controls wouJd be based upon cost,
since aU could be effective and implernentable. Air emission controls would be required
if the level of contaminants released to the atmosphere exceeds health-based criteria.
To remove VOCs from the extracted ground water, air stripping.or UV /Oxidation
has been proposed. In the first two ground water technologies, the extracted ground
w~ter would be treated by air stripping. Air stripping permanently removes
contaminants from the ground water by forcing an airstream through the water, which.
causes the compounds to volatilize. The difference between reinjection and reuse is the
discharge method for the treated ground water. In tbe first technology, the treated
ground water would be reinjected back into the aquifer by means of an injection well
after treatment to MCLs; in tbe second, the treated ground water, which would meet.
MCLs, would be integrated into the City of Hastings' municipal water distribution
system. .
In the third ground water technology, the extracted ground water would be treated
to MCLs with ultraviolet light (UV) and chemical oxidation (oxidation). UV /oxidation
is a chemical process which results in the chemical destruction of the organic compounds
in the ground water. The treated ground water would either be reinjected into the
aquifer or integrated into the municipal water distribution system.
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H any sludges were generated by the water treatment system implemented, the
sludges would be treated off':site at a RCRA Treatment, Storage and Disposal (TSD)
facility in accordance with all RCRA requirements. The sludges would meet the
requirements of tbe land disposal (LDR) restrictions as set forth in 20 CFR part 268.
Action-specific ARARs for the interim action, such as level of treatment for
ground water to meet MCLs, would be achieved. As stated above, the need for
instituting air emission controls would be evaluated based upon the rate of VOC
emission rate from the air stripper. Location-specific ARARs are not applicable.
Chemical-specific ARARs (MCLs) would be met for treated ground water but would not
be met in ground ,."ater which is not extracted from the aquifer.
Cost estimates for these options vary from $2,000,000 to $4,000,000 for the capital
and O&M cost for a 30-year time period.
Source Control
Source control refers to an action or actions to prevent or mitigate the spread of
contamination by removing or containing the source of the contamination. Soil-gas data
indicates that the vadose zone is contaminated and is thus a source of the ground water
contamination. The various source control technologies were assembled in different
combinations and analyzed according to EP A's detailed evaluation criteria. Source
co~trol could be attained by: 1) installing a cap over the current landfill surface in
accordance with the State of Nebraska Title 132 Solid Waste Management Rules; and/or
2) installing a soil vapor extraction system.
An improved cap would provide containment and minimize infiltration through
the landfill. The soil vapor extraction (SVE) process, as stated in the Proposed Plan,
would reD)ove contaminants from the vadose zone. SVE operates by use of a vacuum
system which is placed on an extraction well that is screened in the vadose zone.
Volatiles would be removed from the soils and trapped on carbon for treatment.
.
,
Cost estimates for the source control operable unit including cap improvement
and institutional controls are $180,000 capital costs and $24,500 for annual Operation
and Maintenance (O&M) costs. Cost estimates for full-scale SVE are $542,000 for
Capital Costs and $36,000 for annual O&M costs.'
. .
Chemical-specific ARARs are not met for limited landfill cap improv.ement and
maintenance, but are met for SVE. - . .
SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The NCP sets forth nine evaluation criteria which serve as"1i basis for comparing
the remedial alternatives for final actions. Interim actions, such as those proposed here,
may not achieve final Cleanup levels for the ground water although they are effective in
the short term in preventing further degradation and iIutiating reduction in toxicity,
mobility or volume.
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Nine evaluation criteria were developed by EP A to serve as a basis for comparing
the remedial alternatives for final actions. Interim actions, such as those proposed, may
not fulfill the requirements of all nine criteria.
The nine criteria are divided into three categories: Threshold Criteria, Primary
Balancing Criteria, and Modifying Criteria. If any remedial alternatives identified during
the Feasibility Study do not meet the Threshold Criteria (Criteria 1 and 2), EPA will not
consider them as possible final remedies. If the alternatives satisfy the Threshold
Criteria, they then are evaluated against the next five criteria, called the Primary
Balancing Criteria. These criteria are used to compaI:e the remedial alternatives against
each other in terms of effectivel.ess, degree of difficulty involved, and cost. The 'final
two criteria, state acceptance and community acceptance, are calle~ Modifying Criteria.
The alternatives are compared against the Modifying Criteria after the state and the
community have reviewed and commented on the Proposed Plan and the other
alternatives considered by EP A
Table 5 presents a comparative analysis of how the remedial alternatives satisfy
the Threshold and Primary Balancing Criteria. Evaluation of compliance with the
remaining Modifying Criteria is included in the following discussion. The following is a
discussion of the nine criteria used by EP A for remedy selection.
Threshold Criteria:
Overall Protection of Human Health and the Environment
EP A assesses the degree to which the alternatives would eliminate,
reduce, or control threats to public health and the environment
through removal, containment, and/or institutional controls: An
. alternative is normally considered to be protective of human health
if the excess cancer risk is reduced to a range of 1 in 10,000 (10-4) to
1 in 10 million (10~) and risks do not pose non-carcinogenic health
risks.
Two technologies presented for ground water provide overall
protection of human health and the environment. The No Action
and Limited Action alternatives are not protective. Since the No
Action and Limited Action alternatives. are not considered
protective, the comparative analysis for discussion will focus on the
other protective alternatives for plume management.
Both source control technologies offer protection to human health
and the environment. In addition, by providing contaminant
removal, SVE offers protection of the aquifer.
.
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Compliance with all State and Federal Environmental Regulations
EP A assesses whether the remedial alternatives being evaluated will
comply with all applicable or relevant and appropriate regulations,
called ARARs, established by the state and federal government. As
these are interim actions, full compliance with ARARs may be
delayed until implementation of the final action. The ground water
interim action~ address plume control at a 10-4 risk-based level
which means that the ground water extraction system is required to
pump contaminated ground water at a rate which would stabilize the
contaminant migration by rapid mass removal and hydraulic plume
control. The ground water interim action will provide for treatment
of the extracted ground water to MCLs prior to discharge or
reinjection. SVE as a source control alternative will meet ARARs.
There are three (3) types of ARARs to be addressed; i.e., chemical-
specific, action-specific, and location-specific.
.
Chemical-specific ARARs are requirements that"set final
concentrations of chemicals of concern in the contaminated
material (e.g., ground water, soil) which must be achieved by
the remedial action. These interim remedial actions will not
attain chemical-specific ARARs (referenced in the State of
Nebraska's Title 118 for non-degradation of ground water
standards) in the ground water plume as the target
concentrations of ground water that would be contained
coincides with a 10-4 risk level which, for the primary
compounds of concern at the North Landfill, exceed MCLs.
Chemical specific ARARs will be attained for discharged
ground water after treatment. . All of the plume management
alternatives will comply with MCLs and non-zero MCLs for
the disposition of treated ground water.
"
.
For source control, a waiver of ARARs or further source
control technologies would be needed if it is determined that
contaminants continue to migrate to the ground water.
.
Action-specific ARARs are those requirements that set"
standards on the freatment and discharge components of the
remedial action. Action-specific ARARs will apply to the
interim and final remedial actions, and were considered in
the Feasibility Study. The use of air stripping, with no
emission controls, would result in the- discharge of VOCs
into the atmosphere. NDEC's Title 129 limits discharges of
VOCs to 2.5 tons/year. Air emissions will comply with the
Clean Air Act, 33 V.S.C. ~1251 ~. ~, as well as NDEC's
Title 129, Air Pollution Control and Regulations.
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Technologies for ground water and source"control meet
action-specific ARARs.
Location-specific ARARs are requirements that might apply
to a remedial action due to the site's unique cultural,
archaeological, historical, or physical setting (e.g., wetlands).
Location-specific ARARs will not apply to the ground water
and source control interim or final remedial action at the
North Landfill subsite because there are "no such features in
the subsite area.
.
All remedial action alternatives for source control and plume management
will comply with the following Federal laws:
Clean Water Act
Safe Drinking Water Act
Clean Air Act
Occupational Safety & Health
Act
Solid Waste Disposal Act,
Subtitle C, as amended by
the Resource Conservation
and Recovery Act of
RCRA (1976)
33 V.S.C. ~~1251-1387
42 V.S.C. ~~300f-300j-26
42 V.S.C. ~~7401-7642
29 V.S.C. ~~651-678
42 V.S.C. ~~6901-6992k
In addition, state of Nebraska ARARs for the interim action alternatives for both source
control and plume management alternative ARARs are listed in Table 7.
Primary Balancing Criteria:
Long-Term Effectiveness and Permanence
The alternatives are evaluated based on their ability to maintain
reliable protection of human health and the environment after the
remedial action is completed. This criterion also focuses on the
magnitude of health and environmental risks remaining after the
remedial action would be completed. . .
These are interim action remedies and EP A will evaluate the "
alternatives only on the basis of those wastes which are treated.
These interim actions will not achieve final cleanup levels for the
ground water at the subsite, although they are effective in the short-
" term in preventing further degradation and initiating reduction in
toxicity, mobility ~r volume. Also, as mandated by Section 121(c) of
CERCLA, EP A will conduct 5-year reviews at the subsite as long as
hazardous substances remain above health based criteria. Two years
after implementation of the interim actions, EP A will evaluate the
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information gained to determine the need for soil vapor extraction,
as an additional source control measure.
Reduction of Toxicity, Mobility, or Volume Through Treatment
. This criterion focuses on the amount and types of hazardous
substances that will be destroyed or treated, whether the results of
the remedial action are reversible, and whether the alternative
includes a treatment process. Remedial actions which include
treatment are favored by EP A EP A evaluates t.ach alternative
based on how its treatment methods reduce the harmful nature of
the contaminants, limit the ability of the contaminants to migrate,
and minimize the amount of contamination remaining after the
remedial action is completed.
All of the plume management alternatives will employ treatment to
reduce the toxicity, mobility or volume of the ground water plume.
For source control, the cap improvements will minimize .migration of
contaminants to the ground water which will decrease the volume of
contaminants entering the aquifer and mobility of the ground water
contaminate.d at this subsite.
Short. Term Effectiveness
The length of time needed to implement each segment of the
alternative is considered, and EP A considers the risks that
conducting a particular activity may pose to site workers, nearby
residents, or the local environment.
A Health and Safety plan will be prepared for the implementation
of the response actions which will be conducted. This plan will
provide all the procedures for all site workers to follow during the
testing of the landfill cap, the improvements to the cap, the
installation of the landfill fence, and the installation of the
extraction wells and all associated equipment needed for the ground
water treatment system. Extra care wtll be required if the UV ..
treatment system is selected. The UV technology requires the
careful handling of highly toxic chemicals used for treatment.
Health and safety issues will be addressed at each phase of these
interim response actions.
Implementability
EP A considers the technical (e.g., how difficult the alternative is to
construct and operate) and administrative (e.g., how other
16
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...
government agencies and EPA will coordinate monitoring programs)
feasibility of a remedy, including the availability of goods and
services and personnel (e.g., disposal services, storage capacity)
needed to implement and manage the alternative.
All of the plume management alternatives will be implementable,
although the UV system may require extra time to test the
innovative proeess.
For the source control, both technologies are implementable.
Cost
EP A considers capital costs, operation and maintenance costs, and
Present Net Wonh which is the cost of the activities that will take
place until the remedial action is completed. Capital costs apply to
activities such as construction, land and site development, and
disposal of waste materials. Annual operation and maintenance
costs are spent on activities such as on-going operation of
equipment, insurance and periodic site reviews.
"
All of the plume management alternatives are considered cost
effective based on current information. There is cost uncenainty for
UV which would have to be refined during design. The costs are
~ presented in Table 5. Improvements to the landfill cap are
presented in Option 2 (Limited Action) of the FS. SVE is
presented as FS Option 9 .
ModifYing Criteria:
State Acceptance
The state concurs with the selected remedy as an interim action for
these operable units.
Community Acceptance
EP A held a public comment period to allow the community to
comment on the preferred alternative as set fonh in the Proposed
Plan and the other alternatives considered. EP A received
substantial feedback from the community during the public comment
questioning the benefits and cost of SVE at this subsite. Consistent
with 40 CFR 300.430(£), these comments have prompted EP A to
modify aspects of the preferred alternative. EP A has selected an
interim remedy which is consistent with the preference expressed by
the majority. of the commentors. EP A's responses to these
17
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comments are included in the Responsiveness Summary section of
this document.
SELECTED REMEDIES
EP A selects the following interim actions to address the source control and
ground water operable units at the North Landfill subsite. These selected remedies do
not contain the use of SVE as part of the source control alternative. EP A evaluated the
available information and determined that additional site information was needed to
evaluate the benefit of SVE for site remediation.
SOURCE CONTROL
. Verifying the integrity of the landfill cap and improving the cap as
necessary;
.
Grading the surface of the landfill to promote surface water run-off and
prevent surface water run-on;
.
Fencing the landfill area to restrict access and unsuitable land use such as
farming of unsuitable deep root plants;
.
Requiring deed restrictions by the property owner to prevent construction
and ensure cap integrity;
.
Monitoring subsurface (vadose zone) conditions to determine effectiveness
of the selected interim action remedy.
-
,
GROUND \VATER .
. Extraction of contaminated ground water, (extraction rate to be based on
subsite pump test); .
.
Treatment of contaminated ground water (treatment and treated water
discharge options to be based on implementability, costs and
effectiveness); and
.
Monitoring subsurface (saturated zone) conditions to determine
effectiveness of the selected interim action remedy.
The selected remedies caU for the design and implementation of interim actions
to protect human health and the environment. The goals of these actions are to prevent
further infiltration of surface water into the landfill and to prevent further migration of
the ground water. The ultimate leve~ of remediation to be attained will be determined
in a final remedial action for this subsite. These interim actions wiU be monitored to
determine source control effectiveness and to ensure hydraulic control of the
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contamlnated plume. A final ROD for the source control and groundwater operable
units, which specify the ultimate goal, .remedy and anticipated time-frame, will be
prepared after a period of time as determined by EP A Upon completion of the final
action RIfFS, this interim system may be incorporated into the design of the subsite
remedy specified in the final action ROD.
EP A has identified these interim actions as its selected alternatives because they
provide the best balance among otber alternatives witb respect to tbe evaluation criteria
based on the information available. Eacb of these actions, explained below, shows a
preference for treatment
The EP A bas information' from generators of wastes disposed at the North
LandfIll that tbe Nortb Landfill received RCRA-type bazardous wastes. Since the
landfill operated prior to the enactment of RCRA (November 19, 1980) the RCRA
Subtitle C closure standards are not applicable. However, the standards have been
determined by EP A to be relevant and appropriate due to the type of wastes disposed
and the circumstances of tbe release. Closure of the disposal areas will comply with
appropriate portions of the RCRA regulations- affecting landfill closure and operation
and maintenance. The final cover for this interim action will be designed and
constructed in accordance with tbe Nebraska Solid Waste Management Rules (NDEC
Title 132, Chapter 6).
The Nebraska Solid Waste Management Rules (NDEC Title 132, Chapter 6)
require that a final cover of compacted earth at least two (2) feet thick be placed over
the surface of any solid waste management disposal area wben it is closed. The final
grading must promote surface runoff and prevent surface runon and must support a grass
vegetated cover. This final grade will be maintained as necessary. Since the present cap
was not constructed under an approved plan and is .not presently promoting runoff, the
North Landfill cap effectiveness and degree of cap improvement or replacement that is
necessary will be evaluated. An evaluation of the present cap will be initiated. This
evaluation will inc1ude testing of the cap for permeability and surface characteristics
which will determine the amount and type of improvements necessary. Cap
improvements would be performed under an approved plan to satisfy the NDEC Title
132 requirements and tbe remedial action objectives for the landfill contents.
In addition to the State of Nebraska guidelines, EP A guidance documents wbich
address recommended cap construction design, cap performance criteria, and selection of. . .
appropriate vegetative cover will be consulted during the design of any cap which will be
applied to the North Landfill subsite.
In addition to grading the surface of the landfill and evaluating the integrity of the
cap, the surface will be revegetated to stabilize the soil surface and decrease erosion.
Access restriction at the sub site will be required in order to maintain the cap integrity.
Subsurface monitoring of the vadose zone and groundwater aquifer will be conducted to
assess and monitor subsurface conditions and the. interim action effectiveness. Two years
after implementation of the interim action, EP A will evaluate the information gained to
determine the need for soil vapor extraction as an additional source control measure.
19
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. In order to pump and treat the contaminated aquifer, ground water extraction
wells will be installed near and downgradient of the subsite. The ground water will then
be pumped to the surface at a rate that will prevent further off-site migration of
contaminants and rapidly reduce the contaminant mass in the aquifer. The treated
ground water will either be reinjected or reused to promote conservation of ground
water. System design will be based on a subsite pump test. ,The implementation of
either air stripping or UV oxidation for ground water treatment will be based primarily
on three criteria: cost, short-term m'ectiveness for air emission controls, and
implementability. The EP A will issue an explanation of significant differences which
includes a public notice upon determining the preferred ground water treatment
technology. Ba~ed upon current information, both treatment technologies afford a
similar degree of effectiveness. '
EPA estimates that the interim action will cost $1.0 million dollars in capital.
The Present Net Worth of the remedy, based on operating costs for a 3O-year life, is
estimated to be $2.3 million dollars. These costs are explained in Table 5 and are based
upon information presented to EP A from the PRPs. The costs presented in Table 5
assume that limited cap improvements will be necessary. In addition, the costs prepared
by the City do not include installation of additional monitoring wells, a pump test, or
emission controls. Based upon the above assumptions, EP A beHeves that remedial costs
could be greater than those presented in Table 6. EP A has evaluated the cost/benefit
relationships of the alternatives to the extent possible and has selected the most cost
effective alternatives which meet interim remedial action guidelines.
" ~
STATUTORY DETERMINA nONS
The selected remedies will achieve substantial reduction in risks by initiating the
reduction of the toxicity, mobility and volume of ground water, contaminants, by
containment and removal of ground water contamination to a 104 ,cancer risk level, and'
by reducing environmental risks associated with the contaminated ground water.
The selected remedies meet those ARARs appropriate to this action, based on '
the following Federal and State standards as identified in Section 5 of the FS. Federal
Standards: Safe Drinking Water Act; Clean Air Act; Resource Conservation and
Recovery Act; Occupational Safety and Health Act; and Clean Water Act. The State of
Nebraska Standards is the Nebraska Environmental Protection Act, which includes:
Water Quality Standards; Ground Water Quality Standards; Air Pollution Control'
Regulations; National Pollutant Discharge Elimination Systems; Pretreatment
~egulations; Injection Wells Regulations; Solid Waste Management Regulations; and
Hazardous Waste Management Regulations. Table 7 lists Action-Specific State of.
Nebraska ARARs.
~
The selected interim remedies will protect Duman health and the environment
because the interim actions will reduce contaminant concentrations in the aquifer to a
level that poses significantly reduced risk. This level will be at or below 104, or' a risk of
less then one case in 10,000 due to exposure to contamination. This will provide a ,
20
-------
significant level of protectiveness to human health. In addition to risk reduction, the
interim actions will stabilize the ground water contaminant migration and prevent further
degradation of the ground water through rapid mass removal and hydraulic plume
control. Specifically. the .threat to private well users and the exposure from irrigation
wells will be significantly abated. These interim actions represent the best balance of
trade-offs among alternatives with regard to implementability. effectiveness and cost. A
final remedial action will be prepared. .
Because this remedy will result in hazardous substances remaining on site above
health-based levels. a review will be conducted to ensure that the remedy continues to
provide adequate protection of human health and the environment within five (5) years
after commencement of the remedial action. Review of this subsite and of these
remedies will be ongoing as EP A continues to develop remedial alte.matives for the
North Landfill subsite.
DOCUMENT A nON OF SIGNIFICANT CHANGES
The soil vapor extraction (SVE) component provided for in the PropC?sed Plan
document released by EPA on June 25. 1991 will not be implemented at this time.
During the public comment period. EPA evaluated both direct (soil-gas)"and indirect
(ground water) analytical results to estimate the amount of contamination in the vadose
zone. EP A determined that insufficient information was availabie to complete and
justify the cost of the SVE component in comparison to the amount of contamination
currently present within the vadose zone. Monitoring of the vadose zone will be
conducted during the source control interim action. Two years after implementation of
the source control interim action, EP A will reevaluate the information gained to
determine the need for soil vapor extraction as an additional source control measure.
.
21
-------
NORTH LANDFILL SUB SITE
TABLES A.~D FIGURES
.
22
-------
.\
I
OCA1tON or "AStlNCS Rr.ClON
.""IN nt[ 5'AIt or N£9RASICA
,,. ....
M.-
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~LEGEND
COlORADO AVE,;
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F1GURE 1
. HASTINGS GROUND WAT£R
CONTAMINATION SITE
ARCS Region, VI. VII. VIII
US £.\.~ .1\...411101 ""'ecllelt
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T
North Landfill/Hastings, Nebrask;
. Soil Boring Location~
(April 1988,January & February 1989
Source: Gefaghty & Mi1Ier ,In
Figure 5
, ,
I .
-------
.
.
c
0004
0005/58
. C'
0012
0011
o
[Approximate
Ground Surta.ce
. 0
Elevation
(feet below land surface)
110
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(59.7) T;;
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60
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100
120
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.
Cross Section
. 'rlJl.l"LJOO'..
. .
200
I' ( ) = TCE Concentration
-- . . in ppbv
Sl:Qle m feet
North' Landfill/Hastings, Nebraska
Trichloroethylene Chemical Concentrations in
Soi~Gas Versus Depth:
-------
r
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-------
[
~ [
0'
+ MW.24 .
.
]
]
~
-4
c:J 500-. 1000.PPB
r::1 GT 1000 PPB
, I
+ .MW.26
.
TCE Concentration Greater
Than 500 R»b
N'.-
. JO'
flit
+0-8
North landfill/Hastings, Nebraska
TCE Plume
(Based on Mean 1989
Concentrations) .
Rgure8
-------
Constitueat SQL ~rm::l1 o~gt.s MeaD VCL
:"~.:~:~1;~~~'.;t.~~.~~'~.:..~;....:~~;. ~,'\~:":,:~~;~.(~~:;;:~~i':"~~.f" . ' . ;'~~t~~.<:. ":~'.:~:~
1988 Data 123 S2n11'tes} ~:';:',~,;',:~~<'~~1r:~.:!.t~~ ~.:s :;.'fd ..::~.~~;: :::.~:~':::.::~.~~.
Benzene 1 9 15 - 560 ..5 91
Carbon tetrachloride. 1 1 ".3 0.67 0.95
1,2-;>ichloroethylene 2 14 3.4 - 462 53 97
TetrachloroethyJene I 2 1.3 - 1.7 0-'9 0.69
Trichloroethylene I 14 1.5 - 77 26 36
1989 Data (30 S2mt)tes) ~.:~{.;:;\::~~.;t::~~:tt::~~.~~,.:~.,: .~.}:-:. ~;::::.'~ .,~ i:':'ti~'~~\:;'~?:::< :../J~{~~:~~~~~::~;~f?:~;;:t:::~G.~ ?'~~~~~::1:~::"i.~~. '~:~'::~i~.:~t.,'.:~'
Benzene 10 0 ND ND ND
Carbon tetrachloride 1 0 ND ND ND
1,2-Dichloroethylene R R It It R
TeLrachloroethylene 1 5 1.6 - 3.1 1.2 1.4
Trichloroethvlene 1 22 0.1 - 220 52 75
:"":.:.:,::i/:;:,; .,:::::..:,'.~',:;. . . . '" }:~:::;.:i:.f.~~:~;,'~'~'~;:-/';::F;.r. ::i\:~. ::/:1;:{: : <,,;~t):~.~~ ~': ;':\:.'. ::~~~. .'
1990 Data (9 samt)Jes) ::, \:::~: ;::~.~/~~.:.~~.:.~. :" :'.:::~.; ','..' "
"
Benzene 0.4-4.0 1 0.18 1.6 2.1
Carbon t:t:achloride 0.85 - 8.5 0 ND ND ND
1,2-DichJoroethylene 0.3 - 3.0 3 3.3 - 5.5 3.1 4
Tetrachloroethylene 0.2 -2.0 0 ND ND' ND
Trichloroethylene 0.2 - 2.0 :2 0.4 - 1.4 1.6 :2
Vinyl chloride I 0.3 - 3.0 5 4.0 - 20 7.2 11
. . ' .. . .:' ::.<':.i.:..;.~:.:..t:\::;:':.;.." . ""', :'..' ..r..'~. ,"
~ . . ... ...
.."..".".'........."" ....' ... " . .'''''.::.' '~""i:Y~" :.~::
.. .. ..".. ..
Benzene - I 10 0.2 - 560 32 64
Carbon t::"PGchloride I - 1 4.3 0.67 0.95
1.2-DichJoroethylene I - 17 3.3 - 462 39 71
Tetrachloroethylene I - 7 1.3 - 1.7 0.95 1.1
Trichloroethylene I - 38 0.4 - 220 35 47
Vinyl chloride - 5 4.0 - 20 7.2 11
AU data are reponed 1."1 milli&rams per cubic rnet:r (m&/rrJ) and nre.cstimated'vaJues.
ND Not deteCted. " .
It Rcj~ted data.
SQL Sample q\W'ltitation limit.
UCL Upper 9S percent confidence limit.
. .
.
North Landfill/Hastings, Nebraska
Summary of
Soil-Gas Data
Source: GeraQhty & Miller,lnc.
-------
."
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,
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t... I,... r .....tt.. -lIh ...... -II .1 ..... .... c I.,
r.r (ht. I III......., ------ - -- -.- -- - ---- --------.-----------.. ---_. ----.-...--------- ------...--.... ......
,., r..I. S..... ,Rd C.,..I "..,.1 U, .. Jt "
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, 18". '-II.. ".""8th.,." c." .... re... ,.... -lIh . ... It..." ..... I ... .. .., ,.
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1'.,1".'" 8.h "~.., I
Ii( --.----.--- ---------_. ---------------------.--------------------. ------------------- ---------.-..........
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. 'h'. t......., .. ,......
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. .-----. --._~-- ----- -. ...------------------------.--------------- .------..--...--..- --....--.. .-.....- -.. .
""..,. r.....'I... S.... .... ,...., 'ce.r.... .. ..,., "..,., ".. '" "
'I... ~....,..., ..
r 1.""e.l.r doe...'" .r ......."'.4 ,.
. lI,hll, c~,... ..Rd. , II.. ,.....t,."".. ... t. .S" "
it. "... r"",".. c,''.. ''''.Ino. ..Ic...'c ..h. '.1- ..1e",Ie, "hlc"", ,-, ..II. ...
' It ....., .......... _Ieo. lie."",. ...., .. "' .. --." ...... t. ,
'
""r.r. ,...... I... r...", ...... N the" ,........, fler"" "" .. Jtt "
.
u..c...r ......
4 . .
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~
o
00
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~
North Landfill/Hastings. Nebraska
Regional Stratigaphy
of the Hastings Area
Source: Geraghty & Miner,lnc.
. Table 2
-------
I J
Ran~e Sile Wells MW-6
Constituent of SQLs Prequency RanJ;~ (a) Mean UCL Prequency Ran~e (a) Mean UCL
- ~._. ... -
Acelone 10 - 130 1132 110 12 19 1/13 - 110 21 38
Ben7ene 0.1 - 63 10/38 1.0 - 17 5.6 7.7 9/16 4.0 - 17 10 14
Bromodichloromethane 0.1 - 63 1/36 9.0 4.7 6.8 1/12 9.C 4.8 8.2
2..nutanone 10 - 100 1129 48 8.7 12 1/11 48 13 23
Carbon 'e.r:.chloride 0.1- 5.0 1133 0.41 2.2 2.4 0119 - - -
Chloroform 0.1 - 63 6/36 1.0 - 18 4.9 7.1 3/11 2.0-4.0 2.1 2.7
Chlorometh:.ne 0.1 - 110 2/34 0.5 - 13 8.3 12 1110 13 6.1 7.5
Oihromochloromelhane 0.' - 63 2/36 5.0-7.0 4.8 6.9 1/11 7.0 2.7 3.6
1.2-Dichloroelhane 0.1 - 63 8/36 8.0 - 21 8.1 '11 8/14 8.0 - 21 17 22
I.I-Dichloroelhy!ene 0.1 - 63 14136 1.0 - 29 7.5 10 2/14 1.0 - 26 9.3 15
1.2-Dichloroelhylene 0.1 ~ 5.0 23136 4.0 - 2.000 620 840 14/14 6.0 - 2.000 1,500 1,800
1.2-Dichloroflrop:t11e 0.1 - 50 6134 1.0 - 5.0 3.1 4.3 5/11 2.0 - 5.0 2.6 3.3
Methylene chloride 0.2 - 110 4/36 38 - 150 16 23 4/14 38 - 150 34 51
Toluene 0.2 - 63 1/34 10 . 4.9 7.1 0/13 - - -
Tetrachloroelhylene 5.0 - 63 24141 2.0 - 19 7.9 9.7 12116 5.0 - II 8.6 9.7
I,I.I-Trichloroelhane 0.1 - 63 . 15141 2.0 - 76 13 11 2/19 4.0 - 76 12 19
1.1.2-Trichloroethane 0.1 - 63 1136 10 - 23 7.0 9.4 7/14 10 - 23 14 19
Trichl~oelhylene 5.0 - 49 39141 6.9 - 2.300 820 1,000 .19119 36 - 2.300 1.500 1,800
Vinyl chloride 0.2 - 130 14/35 0.28 - 87 19 25 7113 14 - 87 . 39 51
Xylene (tol3l) 0.1 - 5.0 In8 0.9 2.4 2.5 1/10 0.9 2.3 2.6 .
.
An data are in micrognms per liler (uCn).
a Range or delected concentrations.
SQt.I Sample quanlil3tion limits.
UCL . Upper 95 percent confidence Inteml of the mean.
North Landfill/Hastings, N~braska.
Summary 01 Ground, Water Data
. for On-Site Wells
(MW-6, MW-7, & DW~1)
. Source: Geraghty & MiRer,1nc.
Table 3
, ,
-------
.
-Stp-" .. tableioa.'*'
'AILE 68
T~GET CCNCEl/TUTlDNS FOR POTENTIAL WCIIIOC£IIIC CHEMICALS DET£CTC II GRCl./WWATP
AT THE MASTII1GS tIT' .~TK LAXDFILL litE
'I!"fet Contentrlt I ON for
Slope Feeto" CII8/tg-d8y)-' rsU"Ct] 11»' Cancer lilt lene. CU8/<ar)
".Ight of ....................................... -..............................~........
OI..iee& Cd) Evidence ea) OI'.t IMlt.tlon '1'0-' '1'0-5 'I'O-~
lenaent CA) 0.029 [11111 0.029 PlUm ''0 " '.4
:tIlo~ofo,. elZ) 0.006' Ulll1 0.08' (HEArn " t., O.tIt
'.2-0ichlo~OIthl~ e12) 0.09' UIIS] 0.09' (HEAST) 4S 4.5 o.n
','-DichlorOithene ec) 0.60 nlll1 '.20 (HEAST) 4.5 0.4S O.DI.5
ret~lchlorOithene e12) &1.05' (HEASTJ 0.00'8 [KEAST] ec) 150 15 '.5
rricl'llO~OIthene .(12) 0.011 (HEAST) 0.017 (HEAST) Z90 29 I.t
ilnyl Chloride eA) . ,. t (HEAST) 0.29 [KEAST] eC) s.? 0.J1 0.037
) !PA weiOht of .vidence cllsllflclti~ Icheme for cI"clno;ens: AooNumI~ CI~cino;tn, lufflcient evidence fram
"umI~ api6e!r.iolo;icll atudi.l: ""P~o~!)le NII.'II~ tl~cino;en, tlilittd evl~nc. f~CIIfI apioemiolo;lcll Itudi" Ind ~t.
.viernce fren. Ini"..1 atudi,,: I2..Prce.bly HII.'.n C'p'cino;en, fMd~t. ~idtf'lCe 'ren. apiOeftliological .tudit'l II'Id ~tt
..,ic»nct frCllfl Inill'all Uudi,,: CooPoulble NloINIn CIP'clno;tn, tlilittd .vidtf'lC. In anillllli in the l!::&tf'lCe of hlAal'l dltl:
Coollot classifltd IS to h~.n carcino;e~icity: and E--Evi~nce of noncarclno;tnicityo
I Sourct: 1115 . tht chemic.1 fflts of EPA'. Intesr.ttd li.t Info~t{~ lyat.,. (I' of "'19');
HEAST . H,'lth Eff~t' Asses5ment S~ry Table. CI. of J~ry, 1991); KA. Health Advf.ory (Offfce of
.. Crlntine Wlter).
The i~ll.tion Ilo~ f.etor. wert .stf~tad fran tht following unIt rflt veluel:
5.ZX10-' per m;/"J for tetrlehloroethene, Ind 8.'1'0'2 per ,,/.J for vinyl cJlLoridt.
..~ inl'lltatiOl'\ rate of 20 m3/dlywu au\r.ltd for I 7'D-t; ICiJlt. .
Ea.~lt calc~latlon: (5.2A'O"/m;."J).(70k;/2~3-OIY) . 0.D018 per "Ita-day.
) 1,2'dichloroether.e is not fneludtd beocaus, no ca"oCe~ Ilope faetorl Dr unit rilt veLues
.p" av.ilable; it hi' a Weight of Evldenct Classification of .0. (1115).
-
POOR QUAlITi
OR'-~\:Al
-. I, ..
-------
.
.
.
,_/
17-S..91 Tabll'lob.wt1
'AILE 4b
T.-Cn CCN:EIITUTIOIIS .'" P'OTEIITlAl IIOII:AIIC£I IISO rea
'HENICALS DETECTED III GR~~WATEI
AT THE MASTIIICS Cltf MORTN ~'ILL IITt Ca)
. Irllatltlc.l ~rllatltlc.l Oral 'a'"let cOncentrltlon
Ife I'D 110 'aud on Mlnrd 1,*1
Chllllic:at Ca) r ce) CII;/83) ClC/k,-.) . CII;/kg-.) 0' CIne Cug/I.)
01 I orofof'8 O-lit IA 0.010 C~) 0.010 1111 ,to
'.'-Olchloroethena 0.95 IA 0.0090 C~) 0.0090 1I11 '"
',Z-DlchlorOithene Ctot81) 0.94 8A 0.010 C~) 0.010 WIT Cd) '80
TltrachlorOithena 0.17 ,IA 0.010 Cb) 0.010 II1I "8
Tr(cM orOithena 0.83 'IA D.0074 Cb) D.oo74 IIA "0
Ca) S~rCI of tOllclty IftfoMmitlon: IllS. the ch~ical files of [PA'I Ifttttrattc:l lilt Information lrat.. CII of 6/1191):
MUST. Multh Effects SU'mllry Table Ca. of Jarwry, 1991); ItA. Kulth Mvllory
COfflce of Drlfttins Wlter).
(b) 1ft the absence of an iMalatlon ItD, th. orat IfD I. used for both orat 8I"d IMalation II;IOSUr".
(c) r Is th. constant ratlc brt~ the innalation and th. oral do...
Cd) Chronic IfD for C;I",2'dichlcrolth~ WIS used for 1,Z'dicllloroethene (totll).
(e) .~z~, 1,2'dichlo~thane, a~ vinyl chloride ar. not Included because
tOlictty criteria for noncarcino;~ic .ffeetl ar. not available.
IIA . not avai labl.
\
/
POOR QUALITY
ORIGINAL
-------
TAnl..l~ 5 .. COMPARA'r8vE ANAI,\'SIS OF ALTERNATIVES
CtII"'.."
OWMU ~...... t (1180. "'MI SHOM."',", MIMIC'nOII or WOInCn'I. ~..... COSY
PWOtfCn0t8 or WI'" ARaM l"IIC'M:IlfSs IfffCf1VIIllfSI .0tIII.,"."" VOlUMe ~... '>4
""""M Mil AI- '"."" . """ YMROUOIt tMAtIIf:., "- WoI8W-""
"""'''ft¥t9 11ft tlMllOWlIII'" "'"'''MIllet ..-.t
..... ..... ..... ..... ' " ..... ..... ".. - ................ C80I ........ ...
.., NtP ......
.. AdM ,.. ..... ..... ..... ..... ". -................. ~C8oIt I'.
.................... ~"'II,8M
""-.'" ..............,
~...a... ........-
...... ""-r"''' ,.. .... ..... .. 'I.. .......... NaIl...." ,.. ,. ~o.t-
~"--I .. I -"'... ...,......... ~'~b6" " ~ 0811: I,.
~ -........... ... ---.... ...........-.:.....
_810 --... ...-..........
N¥Ao:. .......-........
-"'....
-....,.. . .
-.-,
...... "--f"''' ,. ..., ....... ,.. ........., NaIl...." ... ,. c.8Ifo.t 1'.-
~~ - "'..... """'._""""--. ~OIM:'"
~ b- .............. ---.... .................
_810. --...~,.....
N¥Ao;. .......- ........
-"'....
, -...., -
--.
,...... ""--r ... tJw ,. -. ..., ..... .. ."88; '--. ........., NaIl...." ... """"""'''''' .,...,o.t 1',- -
IdI8II\ ~ I ..... . ..... "'..... ~ ....,..... ..11-.8......--, 'T_AL ,I '''.'' ".-
~ -... b- 4& ~IR""""''' tI'IT .... """'0111, .,. -...
-.. .....-........., ........ -'"' ........ ..... .... tIIIo4I:
aMAo; . ............. ................. .-....
-"'.... ,......
-....- .
-.
....... ......, c...... .... ..."-- ,.. ,.. ,.. ,. ~o.tl'.-
......_~, ~ """"'" OIUiI:.PI .
.4 ............... 11.-
........ ......, c...... ,. ..... -- ,.. .". ... ,. ~ C80It II."
-"'._~. """"'" 0lIl, II'
....................
....... ......... ... ......... ... "'... ... ...... ,. ......... CItIIIII 00IIt II.IN.
....... -....... I 12.U)
....... .,.11' .,.....
..... .... tIIIo4I:
...... ".ft.
...... r..... ,.. ,.. 'I.. ,.. ,.. ,. c..- 011-....
. """"'" 0lIl: t38
..... MIl"" It'"
,....lAooIo8 .00
POOR QUAL\TY
.. ". OR\G\NAL
'.
.
-
.
-------
.
.
~
\
TABLE ,
ESTIr.1ATED COSTS OF THE SELECTED REr.1EDY
(all values In thousands)
CapitaI Costs:
Treatment Component
Costs
Landfill Cap Testing and Improvements
Site Work
Concrete/Bullding
Process Equipment
Institutional Controls
Contingency (20%)
Total Construction Costs
Legal Costs (5%)
Engineering (15%)
Construction Management (10%)
Total Capital Costs
Annual Operation aDd Maintenance:
MomtoriDg
Inspection and Maintenance
Utility ILabor IMisc.
Annual CostS
Present Net Worth:
15 year O&M PNW (pwf c 10.38)
Total Capital CostS
Total 15 Year PNW .
30 year O&M PNW (p\\i' = 15.37)
Tota1 Capital CostS
Total 30 Year PNW .
.,
Estimated
S 125
129
6S
265
S5
$ 639
128
$ 767
38.5
115
76.5
$ 997
$ 35
7.5
41.5
S 84
.
$ 872' .
997 .
$ 1,869
$ 1,291.3
997
r
S 2,2882
-------
.
t - .
.
,
Table 1
I.
POTENTIAL STAT! ~B
Nebraska Environmental Protection Act
A.
Rules and Regulations Governinq
the Nebraska Pretreatment Program
Effluent Guidelines and ~tandard.
B.
C.
Rules and Regulations Pertaininq
to the Issuance of Permits tffi5'er
the National Pollutant Discharge
Elimination System
Rules and Regulations for Underground
Injection and Mineral Production Wells
Air Pollution Control Rules and
Regulations
D.
E.
...
F.
Nebraska Surface Water Quality
Standards
G. Ground Water Quality Standards and
, . Use Classification
H.
Rules and Regulations Pertaining to
Solid Waste Management
Rules and Regulations Governing
Hazardous Waste Management in
Nebraska
Rules and Regulations Pertaining
to the Management of Wastes
I.
J.
Water Well Standards and Contractors'
Licensi~g Act
A. Regulations Governing Licensure of
Water Well and Pump Installation
Contractors and Certification of
Water Well Drilling and ~p
Installation Supervisors'
III. Nebraska Safe Drinking Water Act
II.
IV.
Regulations Governing Public Water
supply Systems
statutes Relating to Disposal Sttes
A.
v.
statutes Relating to Ground.Water
.
CI'l'J.'l'ION
Neb. Rev. stat.
01. 81,
Article 15
Neb. Adm. Rules
, Regs
Title 121
Neb. Adm. Rules
, Reg.
Title 121' '
Neb. Adm. Rules
, Reg.
Title 11'
Neb. Adm. Rules
, Regs
Title 122
Neb. Adm. Rules
, Regs
Title 129
Neb. Adm. Rules
, Regs
Title 117
Neb. Adm. Rules
, Regs
Title 118
Neb. Adm. Rules
, Regs
Title 132
Neb. Adm. Rules
, Regs
'Title 128
Neb. Adm. Rules
, Regs
Title 126
Neb. Rev. Stat.
Ch. 46
Article 12
Neb. Adm. Rules'
, Regs
Title 178
Neb. Rev. Stat.
Ch.' 71
Article 53
Neb. Adm. Rules
~ "Regs
Title 179
Neb. Rev. Stat.
Ch. 19, ,
Articles 21 ,
41
Neb. Rev. stat.
Ch. 4 6
Article 5
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