United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R07-88/012
July 1988
SEPA
Superfund
Record of Decision:
Shenandoah Stables, MO
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REPORT DOCUMENTATION *• "E^m- NO. 2.
PAGE EPA/ROD/R07-88/012
4. Title and Subtitle
SUPERFUND RECORD OF DECISION
l^henandoah Stables, MO
l^^^rst Remedial Action
^Wfuthorts)
9. Performing Organization Name and Address
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
3. Recipient's Accession No.
5. Report Date
07/28/88
6.
8. Performing Organization Rept. No.
10. Project/Task/Work Unit No.
11. Contract(C) or Grant(G) No.
(C)
13. Type of Report & Period Covered
800/000
14.
IS. Supplementary Notes
16. Abstract (Limit: 200 words)
The Shenandbah Stables (SS) site is located in a rural area near Moscow Mills,
Lincoln County, Missouri, approximately 35 miles northwest of St. Louis, Missouri. The
property includes an enclosed arena and horse stables. There are about 8 residences
located within a 0.5 mile radius of the site, as well as a livestock operation, and
other small businesses on approximately 5- to 10-acre parcels around the facility. The
lies in the upper flood plain of Crooked Creek. In May 1971, the area inside the
ena was sprayed with dioxin-contaminated waste oil for dust control purposes. There
reports that 1,500 gallons of waste material were applied at this time. Following
this spraying, a number of adverse effects were noted; horses and other animals became
ill or died, and the six-year-old daughter of one of the owners was hospitalized for a
variety of symptoms assumed to be related to exposure to contaminated soil. Between
August 1971 and March 1972, approximately 24 to 26 inches of the contaminated material
was removed and disposed of either offsite or onsite in two removal episodes.
Investigations were conducted by EPA in May 1982, which indicated continued exterior and
interior contamination of the facility by dioxin at levels greater than 1,750 ug/kg.
Since the spraying, the site has been flooded a number of times, with water levels
inside the arena as high as four feet above the arena floor. Investigations have shown
(See Attached Sheet)
17. Document Analysis a. Descriptors
Record of Decision
Shenandoah Stables, MO
First Remedial Action
Contaminated Media: soil, structures
Key Contaminants: dioxin
b. Identifiers/Open-Ended Terms
c. COSATI Field/Group
variability Statement
19. Security Class (This Report)
None
20. Security Class (This Page)
None
21. No. of Pages
21
22. Price
(SeeANSI-Z39.18)
See Instructions on Reverse
OPTIONAL FORM 272 <4-77>
(Formerly NTIS-3S)
Department of Commerce
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EPA/ROD/R07-88/012
Shenandoah Stables, MO
First Remedial Action
16. ABSTRACT (continued)
contamination of approximately 8,600 yd^ of interior and exterior site areas. The
primary contaminant of concern affecting the soil and structures at the site is dioxin.
The selected remedial action for this site includes: excavation of all
dioxin-contaminated surface soil exceeding 1 ug/kg with continued excavation until a
residual concentration of 5 to 10 ug/kg at the 2 to 4-foot depth is reached in the arena
and slough, or excavation until bedrock is encountered, with backfilling of excavated
area, placement of the excavated soil in lined polypropylene bags, and storage of the
bags in RCRA-equivalent enclosed steel storage structures onsite; and decontamination of
onsite structures. Approximately 3,300 yd^ of soil are expected to be excavated and
stored. The estimated present worth cost for this remedial action is $3,-936,500.
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RECORD OF DECISION
FOR
NON-FIN.AL MANAGEMENT OF DIOXIN-CONTAMINATED
SOIL AND STRUCTURES AT
SHENANDOAH STABLES
MOSCOW MILLS, MISSOURI
Prepared by:
U.S. ENVIRONMENTAL PROTECTION AGENCY
JULY 1988
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RECORD OF DECISION DECLARATION
SITE NAME AND LOCATION
o Shenandoah Stables, Moscow Mills
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected non-final remedial action for the
Shenandoah Stables site in Moscow Mills, Missouri. This plan has been developed in
accordance with CERCLA, as amended by SARA, and, to the extent practicable, the
National Contingency Plan. This decision is based on the administrative record for
this site. The attached index identifies the items which comprise the administrative
record upon which the selection of the remedial action is based.
DESCRIPTION OF THE SELECTED REMEDY
This remedial action represents the non-final remedial action for dioxin-
contaminated soils and structures at the Shenandoah Stables site. This remedial
action addresses the principal threats at the site by excavation and onsite storage of
soils which exceed the 1 ppb action level established for the protection of public
health and the environment in residential areas.
The major components of the selected remedial action include:
o Excavation of all dioxin-contaminated soils exceeding the health based
criteria - excavate surface soils exceeding 1 ppb at the 95 percent
confidence level using the established sampling protocol, continue
excavation until a residual concentration of 5 to 10 ppb is reached in the
arena and slough at the 2- to 4-foot depth interval or to the 1-foot depth
interval in other areas, or until the 4-foot depth or bedrock is
encountered;
o Placement of excavated soils in lined polypropylene bags and storage of
the bags in RCRA-equivalent enclosed steel storage structures onsite;
o Decontamination of onsite structures.
DECLARATION
The selected remedy is protective of human health and the environment, attains
Federal and State requirements that are applicable or relevant and appropriate to
this remedial action and is cost-effective. Section 121 of CERCLA identifies a
statutory preference for treatment that reduces toxicity, mobility or volume of
hazardous substances. The selected remedy described in this document is a non-
final action that will the reduce the toxicity and mobility of the hazardous material
onsite. However, treatment will not be addressed at this time. Treatment will be
addressed during consideration of the final remedial action alternatives.
7-2
Date j • Morris Kay
Regional Administrator
Region VII
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RESPONSIVENESS SUMMARY
RECORD OF DECISION
FOR
NON-FINAL MANAGEMENT OF DIOXIN-CONTAMINATED
SOIL AND STRUCTURES AT
SHENANDOAH STABLES
MOSCOW MILLS, MISSOURI
Prepared by:
U.S. ENVIRONMENTAL PROTECTION AGENCY
JULY 1988
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RESPONSIVENESS SUMMARY
Record of Decision for
Non-Final Management of Dioxin-Contaminated
Soil and Structures at
Shenandoah Stables
Moscow Mills, Missouri
The Responsiveness Summary provides a mechanism for the Environmental Protection
Agency (EPA) to discuss and respond to comments received from the public on the
proposed remedial alternatives. The proposed non-final alternatives considered by the
Agency were presented in the Operable Unit Feasibility Study (OUFS) and Proposed Plan
for Non-Final Management of Dioxin-Contaminated Soil and Structures at Shenandoah
Stables in Moscow Mills, Missouri!
As required by CERCLA, a notice and brief analysis of the Proposed Plan were published
on June 19, 1988, in the St. Louis Post Dispatch. The public notice provided a brief
overview of the site and identified the lead agency (EPA) and the support agency
(MDNR). The notice informed the public of its role in the decision-making process and
provided information on the public comment period, the location of the information
repositories and methods by which the public could submit oral and written comments.
The notice also presented the preferred alternative and requested public comments on the^
alternatives considered.
To provide the community with a reasonable opportunity to submit written and orr.l
comments on the Proposed Plan and the OUFS report, the EPA established a public
comment period from June 20 through July 11, 1988. The EPA invited requests for a
public meeting in the community to present the Proposed Plan and OUFS, answer
questions and receive comments. ^__
The Proposed Plan, OUFS and Administrative Record file were made available for public
review at the Moscow Mills City Hall and at the EPA Region VII Library in Kansas City,
Kansas. No comments were received by EPA or the State on the OUFS, Proposed Plan,
the preferred alternative or the Administrative Record file during the public comment
period. No request were received to conduct a public meeting.
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DECISION SUMMARY
RECORD OF DECISION
FOR
NON-FINAL MANAGEMENT OF DIOXIN-CONTAMINATED
SOIL AND STRUCTURES AT
SHENANDOAH STABLES
MOSCOW MILLS, MISSOURI
Prepared by:
U.S. ENVIRONMENTAL PROTECTION AGENCY
JULY 1988
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TABLE OF CONTENTS
SECTION PAGE
1.0 INTRODUCTION 1
1.1 SITE SETTING/DESCRIPTION 1
1.2 PAST INVESTIGATIVE AND MITIGATION ACTIONS 1
1.3 ENFORCEMENT ACTIONS 2
1.4 SUMMARY OF SITE RISKS 2
1.5 DOCUMENTATION OF SIGNIFICANT CHANGES 5
2.0 ALTERNATIVES EVALUATED 5
2.1 ALTERNATIVE 1 - NO ACTION 5
2.2 ALTERNATIVE 2 - CAP 5
2.3 ALTERNATIVE 3 - EXCAVATION/STORAGE 5
3.0 COMPARATIVE ANALYSIS OF THE ALTERNATIVES 6
3.1 PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT 6
3.2 COMPLIANCE WITH APPLICABLE OR RELEVANT AND
APPROPRIATE REQUIREMENTS 7
3.3 REDUCTION OF TOXICITY, MOBILITY OR VOLUME 9
3.4. SHORT-TERM EFFECTIVENESS 10
3.5 LONG-TERM EFFECTIVENESS AND PERMANENCE 10
3.6 IMPLEMENTABILITY 11
3.7 COST :. 11
3.8 COMMUNITY ACCEPTANCE .7r.:..;. 11
3.9 STATE ACCEPTANCE 12
3.10 SUMMARY 12
4.0 THE SELECTED NON-FINAL REMEDY 14
4.1 EXCAVATION/CLEAN-UP LEVELS ; 14
4.2 STRUCTURES 15
4.3 STORAGE 15
4.4 HEALTH AND SAFETY 15
4.5 TIME SCHEDULE 15
TABLES
Table 3.7 COST SUMMARY ESTIMATE FOR EXCAVATION/STORAGE
ALTERNATIVE 13
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1.0 INTRODUCTION
1.1 SITE SETTING/DESCRIPTION
The Shenandoah Stables facility is located in a rural area along Highway US-61
near Moscow Mills, Lincoln County, Missouri, approximately 35 miles northwest of
St. Louis, Missouri. Specifically, Shenandoah Stables lies in the west 1/2, northeast
1/4 of section 17, township 48N, range IE of the Troy 7.5 minute USGS quadrangle.
The property lies on the upper flood plain terrace of Crooked Creek in a primarily
agricultural area. There are. a number of single family residences, a livestock
operation and other small businesses on approximately 5- to 10-acre parcels around
the facility. The predominant land use would appear to be pasture land which is
primarily vegetated with fescue.
The property includes an enclosed arena and horse stables building containing a
78.5-foot by 189-foot horse arena, and nearly 100 boarding stalls. The stables are
located on the south side of the arena and are separated by a wall which stops about
one foot from the roof trusses. The enclosed arena building previously contained
bleachers with a capacity for more than 300 spectators and a combination snack bar
and clubhouse area. The arena structure is principally a wood frame structure with
wood poles and trusses and supports and sheet metal walls. Additionally, wood was
used in the construction of the snack bar, stable area, bleachers and gates.
During the early 1970's, activities at the Shenandoah Stables included the boarding,
training and sale of horses, and the staging of horse shows. Children periodically
played in various parts of the arena building. The area inside the arena was
sprayed with dioxin-contaminated waste oil on May 26, 1971, for dust control
purposes. It has been reported that 1,500 gallons of waste material were applied at
this time. Following this spraying, a number of adverse effects were noted; horses
and other animals became ill or died and the six-year old daughter of one of the
owners was hospitalized for a variety of symptoms assumed to be related to
exposure to contaminated soils. In August of 1971, the facility owner reportedly
removed 6 to 8 inches of the contaminated material and disposed of it in the fill for
a portion of US-61, which was under construction at the time. Horses continued to
die after the first excavation effort conducted by the stables owner in March 1972,
an additional 18 inches of materials were reportedly removed by the site owner
from the arena area and buried onsitein a slough area about 75 feet southeast of the
arena structure.
Approximately eight residences are located within a half-mile radius of the site. A
preliminary survey indicates that approximately 22 residents live within the half-
mile radius of the site.
1.2 PAST INVESTIGATIVE AND MITIGATION ACTIONS
A total of four site investigations have been conducted by the Environmental
Protection Agency (EPA) or its contractors and one by the U.S. Fish and Wildlife
Service (USFWS) since the initial screening effort in May 1982, confirmed the
presence of dioxin at this site. These investigations have shown exterior and
interior contamination of the facility by dioxin at levels greater than 1750 parts per
billion (ppb) dioxin. Concentrations of dioxin have spread from the original
sprayed area to adjoining portions of the enclosed facility and to several outside
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exposure leads to altered liver functions and lipid metabolism, and neurotoxicity.
In addition, humans may develop skin lesions, chloracne and hyperpigmentation.
The available epidemiologic evidence concerning the carcinogenicity of dioxin in
humans is inadequate. Considering the available animal carcinogenic and
epidemiologic data, however, the overall weight-of-evidence classification
categorizes dioxin (using EPA's interim classification scheme) as a probable human
carcinogen.
Polychlorinated dibenzo-p-dioxins are a class of chlorinated tricyclic aromatic
hydrocarbons consisting of two benzene rings connected by a pair of oxygen atoms.
According to the position and number of chlorine atoms, it is possible to form 75
different types of chlorinated dioxins. The word "dioxins" is often used to refer to
this class of compounds, especially with respect to the highly toxic 2,3,7,8-
tetrachlorodibenzo-p-dioxin (TCDD) that is present at Shenandoah Stables. This
class of compounds is rather stable in the presence of heat, acids and alkalis. They
are also chemically stable and start to decompose only at temperatures greater than
500 degrees Celsius; the percent of decomposition depends upon the residence time
at high temperature and the proportion of oxygen in the heated zone.
Physico-chemical properties suggest that dioxin will adsorb tightly to organic
material in soil, resulting in low mobility. Once in the soil, degradation processes
tend to be very slow, with half lives estimated to be ten years or longer.
Experimental results show that dioxin will accumulate and concentrate in fish and
wildlife. In mammals, dioxin is readily absorbed through the gastrointestinal tract.
Absorption through skin has also been reported. Absorption may decrease
dramatically if dioxin is adsorbed to particulate matter such as activated carbon or
soil. After absorption, dioxin is distributed to tissues which are high in lipid
content; however, in many species the liver is a major storage area for dioxin.
Metabolism of dioxin occurs slowly, with metabolized dioxin excreted in the urine
and feces. Unmetabolized dioxin can be eliminated in the feces and in the milk.
1.4.2 Risks to Human Health and the Environment
Continued long-term direct contact with soils, ingestion of soils or inhalation of
particulates contaminated with dioxin present the greatest threat to human health.
The principal concern would be for intruders who may disturb contaminated soils.
Ingestion of dioxin would occur if biota containing levels of dioxin were consumed
or by direct ingestion of site soils. Wildlife (deer, turkey, rabbits) entering the site
area would be susceptible to contamination.
Ingestion of plants grown in contaminated soil represents a potential exposure route,
although there is uncertainty regarding the potential for uptake of dioxin in plant
life. Dioxin uptake in many plants appears to be minimal.
The site lies in the upper floodplain of Crooked Creek. A potential exists for
surface contamination to reach Crooked Creek via stormwater.
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The Center for Disease Control, through the Agency for Toxic Substances and
Disease Registry (ATSDR) has recently provided supplemental information to the
1984 paper by Kimbrough, et aL, in a series of correspondence between ATSDR and
EPA which evaluates exposure to dioxin contaminated soils. This information has
supported excavation and removal of surface soils exceeding an average
concentration of one part per billion (ppb), initially determined prior to excavation
at the 95 percent confidence level using the established sampling protocol. In
addition, the ATSDR has recommended that excavation continue until: a residual
concentration of 5 to 10 ppb is reached in the arena and slough at the 2- to 4-foot
depth interval; a residual concentration of 5 to 10 ppb is reached in all other areas
at the 1-foot interval; or a total depth of 4 feet or bedrock is reached. Removal of
soil to a greater depth in the horse arena and slough has been recommended since
historical evidence indicates these areas were previously disturbed. The Agency has
considered this information and these recommendations in the process of selecting
this non-final remedy.
1.5 DOCUMENTATION OF SIGNIFICANT CHANGES
The selected remedy presented in this document is identical to the remedy proposed
in the EPA Proposed Plan of June 1988.
2.0 ALTERNATIVES EVALUATED
The EPA evaluated three alternatives proposed for the non-final remediation of
Shenandoah Stables. The non-final remedial alternatives considered during this
evaluation were 1) no action, 2) cap and 3) excavation/storage. A description of the
alternatives is provided below.
2.1 ALTERNATIVE 1 - NO ACTION
Under the no-action alternative, no additional remedial actions would be taken at
the site. Installation of security fencing and posting of warning signs may be
considered part of this alternative.
2.2 ALTERNATIVE 2 - CAP
The primary components of this alternative are limiting public access, demolition of
site structures, placement of a six-inch soil cover and porous mat over the
demolition debris and ground surface and promoting vegetation by seeding and
fertilization. This alternative would serve to provide a stable cover over site
grounds thus reducing erosion potential. The site would be maintained and
monitored until final remedial actions are implemented (assume approximately 10
years).
2.3 ALTERNATIVE 3 - EXCAVATION/STORAGE
This alternative would involve decontaminating existing onsite structures and
excavation of surface soils at the site that are contaminated at concentrations
exceeding the health based criteria. Surface soils exceeding an average
concentration of 1 ppb, initially determined prior to excavation at the 95 percent
confidence level using the established sampling protocol, will be excavated.
Excavation of soil would proceed until a residual concentration of 5 to 10 ppb is
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The no action alternative would essentially maintain the conditions as described and
allow the continued potential for dioxin migration offsite. The migration of
contamination is expected to continue and possibly increase as the unauthorized
trespass and activities are conducted at the arena. Contamination is also leaving the
site and entering the environment via wildlife through the food chain. The
potential for offsite migration via wind and water erosion will also continue.
Proper containment of the contaminated material is the only means to mitigate or
eliminate the continued migration of dioxin into the environment.
The cap alternative would provide a reduction in dioxin migration via surface
water, air and area biota. Subsequently the threat of exposure to site workers or
intruders, intruding wildlife and downstream biota would be reduced. However,
long term maintenance would be required to assure the caps integrity. Borrowing
animals, erosion and other environmental and man induced conditions could
compromise the caps integrity.
The excavation of dioxin contaminated soils would remove the threat of exposure.
Excavation would remove dioxin contamination to a level below health based
criteria. Short-term potential migration may be experienced during soil disturbance
activities. However, the long-term degree of protection significantly outweighs the
short-term impacts, by eliminating the contaminant source and greatly reducing the
potential for dioxin migration over the long-term. Dust and particulates may be
generated during materials handling and preparation activities. Measures would be
taken to ensure that these potential hazards are controlled prior to full-scale
operation. Workers would be protected through mitigative measures, project-specific
health and safety plans and by adherence to Occupational Safety and Health Act
(OSHA) regulations. During onsite remedial activities continuous ambient air
monitoring will be conducted around the site.
3.2 COMPLIANCE WITH APPLICABLE OR RELEVANT AND
APPROPRIATE REQUIREMENTS
Section 121(d) of CERCLA, as amended by SARA, requires that remedial actions
comply with applicable or relevant and appropriate requirements (ARARs) under
Federal and State environmental laws. The following potential ARARs have been
identified and evaluated for remedial alternatives at Shenandoah Stables:
o Resource Conservation and Recovery Act
o Toxic Substance Control Act
o Federal and State Water Quality Criteria
o Federal and State Air Pollution Control Requirements
Those ARARs which have the most substantial impact on the remedy selection are
discussed below.
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disposal of PCB items are located at 40 CFR 761.65. The Federal TSCA regulations
are applicable to the Shenandoah Stables site since concentrations of PCB's have
been detected at levels exceeding SO ppm. The selected remedial action will comply
as necessary with the technical requirements of TSCA.
3.2.3 Federal and State Water Quality Criteria
Federal ambient water quality criteria (established pursuant to Section 303 of the
Clean Water Act at 40 CFR Part 120) provide an estimate of the ambient surface
water concentration that will not result in adverse health effects in humans, or the
concentrations associated with certain incremental cancer risks. Federal and state
ambient water quality criteria for PCBs and 2,3,7,8-TCDD are zero. Federal and
state ambient water quality criteria represent enforceable regulatory standards, and
are applicable to any alternative involving discharge into the Crooked Creek.
Runoff carrying soil particles will be controlled during implementation of the
selected remedial action to eliminate non-point discharges of dioxin or PCB to
Crooked Creek. No point source discharges will be made to Crooked Creek as a part
of the selected remedy.
3.2.4 Federal and State Air Pollution Control Requirements
The technical and administrative requirements of the Federal and Missouri Clean
Air Acts specify air quality standards and regulate hazardous substance emissions
from stationary sources. The Missouri Air Pollution Control Regulations,
administered by the Air Conservation Commission at 10 CSR 10 regulate
contaminant and particulate air emissions from a variety of sources. These
requirements applicable to the selected remedial action at Shenandoah Stables which
may result in emissions of air contaminants of fugitive particulate matter (dust) will
be addressed in the design and implementation of the remedial action.
3.3 REDUCTION OF TOXICITY, MOBILITY OR VOLUME
This evaluation criteria relates to the performance of a technology or remedial
alternative in terms of eliminating or controlling risks posed by the toxicity,
mobility, or volume of hazardous substances.
Dioxin contaminated soil would remain in place under the no action and cap
alternatives. Capping would reduce mobility of contaminated soils. However, the
toxicity of the contaminants would remain at current levels. If in the future it is
determined that removal of contaminated soil is required, removal of the
uncontaminated cover material would also be necessary. It would be difficult to
completely segregate the cover material from the underlying contaminated soil
during removal. Thus the volume of material possibly requiring future management
would be increased by the additional volume of the cover.
Excavation of all soils contaminated with dioxin above the health based action
level will provide the greatest assurance against contaminant migration. The
toxicity and volume of dioxin contaminated soils would remain the same, however,
contaminant mobility would be eliminated. The selected method of soil storage will
contain soils in lined polypropylene bags and contain those bags in an enclosed
storage structure. This method provides assurances that mobility and risk of
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3.6 IMPLEMENTABILITY
Implementability addresses how easy or difficult, feasible or infeasible, an
alternative would be to carry out from design through construction, operation and
maintenance.
The no action alternative would easily be implemented since it requires minimal if
any coordination of activity. Implementation of the cap alternative will require
detailed design and competent supervision. Implementation time is approximately 2
months.
Implementation of the excavation and storage alternative requires the careful design
and operations planning, considering many ongoing and simultaneous activities.
Similar actions have successfully been implemented at several other dioxin
contaminated sites in Missouri. Experienced gained during these related activities
have provided a means for the Agency to refine and perfect the protocol and
procedures implemented during the site remedial action. This alternative could be
implemented immediately and completed in approximately 25 weeks.
3.7 COST
CERCLA requires that EPA select the most cost-effective (not merely the lowest
cost) alternative that protects human health and the environment and meets other
requirements .of the law. The no action alternative, which would not involve any,
cost, was considered in order to meet requirements of the law. The cap alternative?
would involve costs of approximately S 1.377 million in comparison to the
excavation and storage alternative which would involve a cost of approximately S4.0
million. See Table 3.7 for itemized costs.
Considering the increased protectiveness and long-term reliability of excavating
dioxin contaminated soils, the impacts associated with the costs of the non-final
remedy, the most cost effective alternative is excavation, and storage. The costs of
the excavation/storage alternative in excess of those for the cap alternative are
justified since the final remedy currently planned will require excavation of dioxin
contaminated soils. The increased volume of the cap materials would subsequently
increase final remedy costs. The advantages offered by excavation and storage thus
far outweigh those offered by other alternatives.
3.8 COMMUNITY ACCEPTANCE
This evaluation criteria .addresses the degree to which members of the local
community support the remedial alternatives being evaluated.
The local community has not recently expressed concern over remediation of the
Shenandoah Stables site. This Proposed Plan stands as the first presentation to the
public of the alternatives considered.
The Proposed Plan, Operable Unit Feasibility Study and Administrative Record
were provided at the Moscow Mills City Hall (repository) on June 20, 1988. At
Public Comment Period was held open for 21 days,'until July 11, 1988. No persons'
visited the repository during this period. The EPA received no comments, otherwise,
to the Proposed Plan and no requests for a public meeting were received.
11
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Table 3.7
COST SUMMARY ESTIMATE FOR EXCAVATION/STORAGE ALTERNATIVE
CONSTRUCTION COSTS
U.S. EPA Dioxin Excavation Contract $
Site Security at $250/day 33,250
Mobilize and Prepare Health & Safety Plan 75,000
Mobilization of Excavation Equipment 20,000
Site Management, Trailer and Utilities 132,000
Excavation and Interior Decon 2,250,000
Backfill Soil § $10/yd 37,500
Restoration 50,000
Other Supplies 25,000
Subtotal of Dioxin Excavation Contract $2,622,750
15% Contingency 393,412
CONSTRUCTION SUBTOTAL $3,016,162
U.S. EPA Dioxin Building Contract $ 225,000
3 Storage Facilities
U.S. EPA Dioxin Polypropylene Bag Contract
2500 Bags $ 100,000
CONSTRUCTION/CLEAN-UP CONTRACTOR SUBTOTAL $3,341,162
SAMPLING/OVERSITE COSTS
U.S. EPA Dioxin Lab Contract
Soil Samples - 205 @ $200 41,000
Air Samples - 175 @ $200 35,000
U.S. EPA TECHNICAL ASSISTANCE TEAM 225,000
15% Contingency 33,750
SUBTOTAL 334,750
TOTAL (EXTRAMURAL) 3,675,912
U.S. EPA COSTS
Labor $ 55,575
Overhead 155,000
Travel 50,000
SUBTOTAL $ 260,575
TOTAL (INTRAMURAL) COST $ 260,575
TOTAL PROJECT COST $3,936,487
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4.2 STRUCTURES
Previous sampling has not shown contamination inside a nearby residence but
extensive contamination inside the arena structure exists. Because of the threats
discussed above, this contaminated material will be removed by a combination of
dry abrasive blasting and HEPA vacuum while the structure is maintained under a
negative pressure so contamination is not spread to outside areas.
4.3 STORAGE
The storage structures to be used for the temporary consolidation of the
contaminated soil and debris will be constructed to satisfy the applicable storage
structure requirements of 40 CFR Part 264 Subpart I issued pursuant to the
Resource Conservation and Recovery Act (RCRA). The foundation of the storage
structures will be constructed at an elevation above the 100 year flood level (479
MSL). The storage consists of subgrade preparation and placement of a multi-layer
rolled asphaltic floor with a continuous 8-inch asphaltic curb with sealer applied. A
wood-framed, steel-sided building will be constructed over the entire floor and curb
area. These storage structures will be located inside a separate fenced and posted
area for the duration of the. storage period. Following completion of the removal
activity, regular scheduled inspections of the structures, fence system and condition
of the stored material will be conducted.
4.4 HEALTH AND SAFETY
A health and safety plan, similar to plans prepared and used satisfactorily at other
eastern Missouri dioxin sites, will be prepared for the Shenandoah Stables site and
implemented during the non-final remedial action. An air monitoring program will
be implemented prior to initiation of excavation and continued throughout the
active excavation phases of the project to monitor any offsite migration of
potentially contaminated dust. All active portions of the site and unsecured storage
buildings will be monitored during non-work hours by trained security personnel
operating from an office on the storage structure grounds. Security during the
active project phases will insure that no unauthorized personnel will be allowed
access to the site. Contingency plans have been prepared in the event that natural
or technological events cause the unplanned release or potential release of hazardous
materials at the site.
4.5 TIME SCHEDULE
It is estimated that the entire action will take 150 work days (25 weeks) from the
beginning o.f the initial onsite mobilization. Thirteen weeks are allowed for
excavation of the contamination and an additional three weeks for completion of
restoration and demobilization.
15
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