Is Ctr.
97216
PB98-964107 i-x
EPA 541-R98-094
November 1998
EPA Superfund
Record of Decision:
Penta Wood Products Inc.
Daniels, WI
9/29/1998
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RECORD OF DECISION
FINAL REMEDIAL ACTION
PENTA WOOD PRODUCTS SUPERFUND SITE
TOWN OF DANIELS, WISCONSIN
SEPTEMBER, 1998
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TABLE OF CONTENTS
CONTENT PAGE NO.
DECLARATION
DECISION SUMMARY 3
I. SITE NAME, LOCATION, AND DESCRIPTION 3
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES 3
III. HIGHLIGHTS OF COMMUNITY PARTICIPATION 5
IV. SCOPE AND ROLE OF THE RESPONSE ACTION 5
V. SUMMARY OF SITE CHARACTERISTICS 6
A. Land Use 6
B. Surface Water 6
C. Geology • 7
D. Hydrogeology 7
VI. MAJOR FINDINGS OF THE REMEDIAL INVESTIGATION
AND RISK ASSESSMENT 9
A. Source Areas 10
B. Fate and Transport of Site-Related Contaminants 12
VII. SUMMARY OF SITE RISK 15
A. Objectives 15
B. Human Health 16
C. Ecological Risk Assessment 20
VIII. REMEDIATION OBJECTIVES 23
IX.. DESCRIPTION OF ALTERNATIVES 24
A. Alternative 1 24
B. Alternative 2 25
C. Alternative 3 33
D. Alternative 4 34
E. Alternative 5 35
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X. SUMMARY OF THE COMPARATIVE ANALYSIS OF
ALTERNATIVES 36
A. Threshold Criteria 36
B. Primary Balancing Criteria 36
C. Modifying Criteria 37
XI. THE SELECTED REMEDY 40
A. Cleanup Levels 40
B. Description of Remedial Components 42
C. Long-Term Monitoring Plan 43
XII. STATUTORY DETERMINATIONS 44
A. The Selected Remedy is Protective of Human
Health and the Environment 44
B. The Selected Remedy Attains ARARs 44
C. The Selected Remedy is Cost Effective 47
D. The Selected Remedy Utilizes Permanent Solutions and
Alternative Treatment or Resource Recovery
Technologies to the Maximum Extent Practicable 48
E. The Selected Remedy Satisfies the Preference for
Treatment that Permanently and Significantly Reduces
the Toxicity, Mobility, or Volume of the Hazardous
Substances as a Principal Element 49
XIII. DOCUMENTATION OF SIGNIFICANT CHANGES 49
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TABLE OF CONTENTS
(continued)
TABLES
Table 1
Table 2
Table 3
Table 4
Table 5
Table 6
Table 7
Table 8
Preliminary Remedial Goals and Clean Up Goals for Constituents of Potential
Concern in Soil
Preliminary Remedial Goals and Clean Up Goals for Constituents of Potential
Concern in Ground-Water
Summary of Site Risk to Human Health
Summary of Site Risk to Ecological Receptors
Preliminary Remedial Goals for Constituents of Potential Concern in
Sediment
Preliminary Remedial Goals for Constituents of Potential Concern in Surface
Water
Components of the Remedial Alternatives
ARARs Criteria and Guidance for the Selected Remedy
FIGURES
Figure 1 Site Location Map
Figure 2 Site Features Map
Figure 3 Site Conceptual Model Cross Section
Figure 4 1994 and 1997 PCP Concentrations in Ground-Water
Figure 5 Excavation and Cover Areas
APPENDICES
Appendix A WDNR Letter of Concurrence
Appendix B Administrative Record Index and Administrative Record Locations
Appendix C Responsiveness Summary
LIST OF ACRONYMS
REFERENCES
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DECLARATION
SELECTED FINAL REMEDIAL ACTION
FOR THE
PENTA WOOD PRODUCTS SUPERFUND SITE
TOWN OF DANIELS, WISCONSIN
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for the Penta Wood Products Superfund Site
(PWP Site) in the Town of Daniels, Wisconsin and describes the legal and technical basis for the selection.
The remedial action was chosen in accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) of 1980, as amended by the Superfund Amendments and
Reauthorization Act (SARA) of 1986, 42 U.S.C. sections 9601-9675, and is in compliance with the
National Oil and Hazardous Substances Pollution Contingency Plan (NCP) to the extent practicable. This
decision is supported by documentation contained in the Administrative Record for the PWP Site.
The Wisconsin Department of Natural Resources (WDNR) concurs with the selected remedy.
ASSESSMENT OF THE PWP SITE
IL i Actual or threatened releases of hazardous substances from the PWP Site, if not addressed by implementing
^•>* the response action selected in this Record of Decision (ROD), present a potential future threat to public
health, welfare, or the environment.
DESCRIPTION OF THE SELECTED REMEDY
This final remedial action addresses contamination associated with contaminated soils and sediments,
surface water, a light non-aqueous phase liquid layer (LNAPL), and a ground-water plume at the PWP
Site. The statutory and regulatory requirements for the remedial action at the PWP Site are to:
Reduce/eliminate the potential risks to human health and ecological receptors associated with
exposure to pentachlorophenol (PCP) and fuel oil components in surface and ground-water,
and PCP/fuel oil components and metals in the soil and sediment;
Reduce/control the source of contaminants;
Reduce the concentrations of these compounds in the ground-water plume to PALs and;
Satisfy Applicable or Relevant and Appropriate Requirements (ARARs).
The selected remedial alternative for the PWP Site is Alternative 3: Soil and Sediment
Consolidation, Bioventing, LNAPL Collection and Disposal, Ground-Water Collection and
* Treatment associated with LNAPL Collection, and Monitored Natural Attenuation for the
remainder of the ground-water plume. The selected remedy focuses on removing free phase
LNAPL and the grossly contaminated ground-water while slowly drawing down the water table
and enhancing natural biodegradation of the soils above the LNAPL by bioventing (adding air to
t, I the soils above the water table). PCP/fuel oil contaminated soils and sediments will be
consolidated under a cover prior to bioventing. Arsenic/metals contaminated soil will be
segregated where possible; highly contaminated soils will be solidified in cement and placed in a
Corrective Action Management Unit (CAMU). The overland transport of contaminated site
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materials from a lagoon with a collapsing wall to an adjacent wetland, will be eliminated with a
buttress, graded, and vegetation established. The natural degradation of contaminants that is
occurring in the ground-water plume will be monitored. If monitoring detects that off-site
receptors are threatened, or if the remedy fails to effectively reduce contaminant mass within a
reasonable time period, contingency plans will be implemented. The major components of this
remedy include:
Building demolition
Segregation, select solidification, and placement of all arsenic soils in a CAMU
Consolidation of PCP/fuel oil soils and wood chips under a soil cover
Bioventing POP'fuel oil contaminated material
Biopad removal and backfill on-site
Erosion control measures
Revegetation
LNAPL removal
Grossly contaminated ground-water collection, treatment and discharge
Monitored natural attenuation
Institutional controls
Environmental monitoring/maintenance
Point-of-use carbon treatment, if necessary
Fhre-year site reviews
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment, complies with federal
and stale requirements that are legally applicable or relevant and appropriate to the remedial
action, and is cost effective. This remedy utilizes permanent solutions and alternative
treatment or resource recovery technologies to the maximum extent practicable and satisfies the
statutory preference for remedies that employ treatment that reduces toxicity. mobility, or
volume as a principal element. Because this remedy will result in hazardous substances
remaining on site above health based levels, a review will be conducted at five-year intervals
after startup of the remedial action, to ensure that the remedy continues to provide adequate
protection of human health and the environment. This five-year review will be conducted as
long as hazardous substances are present above health-based cleanup levels.
STATE CONCURRENCE
Upon receipt, the State of Wisconsin concurrence letter will be included in the Administrative
Record and Appendix A of this ROD.
William E. Muno Date
Superfund Division Director
U. S. EPA Region V
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DECISION SUMMARY
FINAL SELECTED REMEDIAL ACTION
FOR THE PENTA WOOD PRODUCTS SITE
I. SITE NAME, LOCATION, AND DESCRIPTION
The PWP site is an inactive wood treating facility located on Daniels 70 (former State Route 70)
in Burnett County, Wisconsin. It is approximately 78 miles northeast of Minneapolis, Minnesota,
and 60 miles south of Duluth, Minnesota (Figure 1). The Village of Siren, Wisconsin, is
approximately 2 miles east of the site and there are two residences within 200 feet of the site using
private wells.
The PWP property currently consists of approximately 82 acres which were actively used; 40
undeveloped acres consisting of forest were sold after the facility closed. The property is located
in a rural agricultural and residential setting and is bordered to the east, west, and north by
forested areas; some of these areas are classified by the State of Wisconsin as wetlands. With the
exception of an 8 acre parcel, Daniels 70 forms the southern property boundary.
The PWP site is situated on a plateau with a 110-foot drop in elevation from the southern boundary
to the northern boundary. The site stratigraphy consists of three layers: an upper sand, a glacial
till that is not continuous throughout the site, and a lower sand. The depth to ground-water is over
100 feet on the plateau. Ground-water occurs both in a thin unconfined aquifer and within a multi-
layered semiconfmed aquifer system. The regional ground-water flow direction is to the north.
Since the closing of the on-site production well, ground-water flow at the site has been radial, with
a strong'downward vertical gradient. A number of surface water bodies are present north and east
of the site.' Doctor Lake and an unnamed lake are located 2,000 feet east and northeast of the site,
respectively. Approximately 2,137 acres of lakes, 94 acres of bogs, and 7,500 acres of wetland
are located within a 4-mile radius of the site. A wetland is located within 130 feet of the northern
property boundary. The Amsterdam Slough Public Hunting area covers 7,233 acres and is located
1 mile north of the site.
There are no viable PRPs capable of financing the selected remedial activity at the site. The
remedy will be a fund financed remedial action.
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES
PWP operated from 1953 to 1992. Raw timber was cut into posts and telephone poles and treated
with either a 5 to 7 percent PCP solution in a No. 2 fuel oil carrier, or with a water borne salt
treatment called Chemonite consisting of ammonia, copper II oxide, zinc and arsenate (ACZA).
PCP also conducted toll blending of pentachlorophenol and fuel oil on a contract basis for other
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industrial users just prior to closing in 1992. During its 39 years of operation, PWP discharged
wastewater from an oil/water separator down a gully into a lagoon on the northeast corner of the
property (Figure 2). Process wastes were also discharged onto a wood chip pile in the
northwestern portion of the property. Ash from a boiler was used to berm a cooling pond.
Beginning in the 1970s. WDNR investigators noted several large spills, stained soils, fires, and poor
operating practices.
PWP began an environmental investigation in 1987. In 1988. the on-site production well was closed
for potable use when it was found to contain 2.700 parts per billion (ppb) of PGP. The State of
Wisconsin Department of Justice filed a prelim man injunction against Penta Wood Products in
1991. citing WPDES violations and violations of other State statutes regarding storage of raw
materials, and waste handling practices. The facility voluntarily closed in May 1992 with the
promulgation of the Resource Conservation and Recovery Act (RCRA) drip track regulations.
The site was put into the Supertund Accelerated Cleanup Model (SACM) pilot program in 1993.
The site was listed on the National Priorities List on June 17.19%. A removal action was conducted
from 1994 to 1996. The ACZA treatment building and half of the oil/water separator building were
demolished and remaining chemicals and sludges were disposed off-site. Grossly PCP-and metals-
contaminated soils were excavated and disposed off-site, and metals-contaminated soils were
excavated and mixed with cement on-site to form a 3 -acre concrete biopad.
The nature and extent of contamination has been characterized in soil, sediment, surface water, and
ground-water on and immediately north of the site Subsurface soils are contaminated with the
PCP/oil mixture to a depth of over 100 feet beneath the gully leading from the oil water separator
to the lagoon (Figure 3). A floating PCP/oil (LNAPL) layer covers an estimated 4-acre area acting
as a source of contamination to the ground-water plume. The northern lagoon wall is collapsing and
overland transport of PCP/oil saturated soil and wood debris has resulted in sediment and surface
water contamination in the off-site wetland. Wastewater was also discharged into wood chip piles
formed during the manufacturing process. Surficial soils east of the treatment area, down to two feet
deep, are contaminated with arsenic, copper, and zinc. The metals-contaminated soil extends from
the treatment building into a wooded area on the eastern site boundary. PCP contamination of
surface soils exist along the gully corridor and in hot spots in the treatment area, and where treated
wood was stored. Emergency erosion control measures were taken in 1998 in an effort to reduce
washout of contaminated wood debris from the lagoon wall into the wetlands.
Based upon currently available information, Penta Wood Products, Inc. (Penta Wood) is the only
potentially responsible party at the PWP site. Penta Wood was the owner and operator of the site
at the time of disposal of hazardous substances including PCP and arsenic. Legal title to the property
is still held by Penta Wood.
On August 12,1993, U.S. EPA issued a unilateral administrative order to Penta Wood pursuant to
Section 106(a) of CERCLA. The order required Penta Wood to perform certain removal activities
at the she. In an August 23.1993 letter, Penta Wood's attorney advised U.S. EPA that Penta Wood
did not have the financial ability to comply with the requirements of the order. U.S. EPA and Penta
Wood subsequently entered into a consent decree requiring, among other things, that Penta Wood
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pay U.S. EPA $37,400 in partial reimbursement of its past response costs. The consent decree was
entered by the United States District Court for the Western District of Wisconsin on April 11,1996
and the complaint was filed on the same day.
III. HIGHLIGHTS OF COMMUNITY PARTICIPATION
A complete chronology of community relations activities for the PWP Superfund Site is provided
in the Responsiveness Summary (Appendix C). Recent activities include issuance of the Remedial
Investigation/Feasibility Study (RI/FS) report and the Proposed Plan for the PWP Site. These
documents were introduced into the Administrative Record in June, 1998. PWP Site documents are
available to the public as part of the Administrative Record which is housed at two locations: (1)
U.S. EPA Docket Room for Region V in Chicago, Illinois; (2) Burnett Community Library in
Webster, Wisconsin. An information repository housing key documents, has also been established
at the Grantsburg Public Library in Grantsburg, Wisconsin. The Administrative Record Index and
addresses of the Administrative Record locations are presented in Appendix B.
A public comment period was held from July 7, 1998, to August 8, 1998. U.S. EPA ran a public
notice on July I, 1998, in The Inter-County Leader and Burnett County Sentinel to announce the
comment period and the public meeting date. A public meeting was held July 15, 1998, at the
Burnett County Government Center in Siren, Wisconsin. The meeting included a presentation on
site history and the proposed remedy. No public comments were received during the public
comment period. A listing of community involvement activities is included in the Responsiveness
Summary (Appendix C).
IV. SCOPE AND ROLE OF THE RESPONSE ACTION
The final remedy for the PWP Site provides a comprehensive, proactive approach for site
remediation. The free phase floating PCP/oil LNAPL, residual soil contamination and the highly
contaminated groundwater serves as a continuous source of ground-water contamination. The
remedy includes removing the free phase LNAPL and associated highly contaminated ground-water,
while dewatering the thin unconfined aquifer below the LNAPL area. The separated PCP/oil phase
will be incinerated off-site, and the highly contaminated ground-water will be treated and
reinfiltrated. The exposed residual PCP/oil in the smear zone, the 100 feet of PCP/oil-contaminated
unsaturated soil column, and the consolidated soils beneath the soil cover, will be degraded by
enhanced natural biodegradation using bioventing. Remaining ground-water contamination will
continue to naturally attenuate and degrade. Exposure to surficial soil and sediment contaminants
will be controlled by consolidating these materials under the soil cover; fencing; installing a buttress
between the lagoon and the wetland; grading the slopes and revegetating the site for erosion control.
The highly contaminated arsenic soil will be immobilized by solidification, and all arsenic-
contaminated material will be consolidated in the CAMU. The erosion control measures will be
periodically inspected, and repaired as necessary. Subsurface soil concentrations, and ground-water
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concentrations will be monitored as established in the Operations and Maintenance plan, to establish
the progress of the remedy. Institutional controls will be used to restrict use of land and ground-
water at the site. Contingency plans will be developed, and implemented as necessary, to insure
timely compliance with the clean-up criteria.
These remedial actions will prevent the potential for future human health and environmental risks
associated with exposure to PC P. fuel oil components, and metals in the soil, sediment, and ground-
wafer by (I) removing the ongoing source of PCP to the ground-water (2) reducing residual PCP/oil
concentrations in the vadose soils (3) immobilizing the metals-contaminated soils (4) eliminating
the exposure pathway to the metals-contaminated soils and the PCP/oil-contaminated soils and
sediments, while they are biodegrading (5) eliminate overland flow of contaminated materials to the
wetland and (6) reducing ground-water contaminant concentrations. In the event that monitoring
shows that PGP soil and ground-water concentrations are not decreasing at an acceptable rate,
additional remedial action will be considered. This may include in-situ oxidation, steam heating of
the smear zone to enhance draining of the PCP/oil mixture, addition of moisture and/or nutrients to
enhancement bioremediation rates, in-situ chemical oxidation or other technology considered
appropriate at the time. A contingency plan will be developed and implemented in the event that
monitoring shows exceedences of criteria at off-site receptor locations.
V. SUMMARY OF SITE CHARACTERISTICS
A. LAND USE.
Land use in the area of the PWP Site is a mixture of agricultural, industrial, residential, and
recreational. There are no zoning laws in effect. Future surrounding land use is likely to be
residential and recreational. Potential future land uses of the PWP Site might include light industry
or a tree farm on the majority of the site not under soil cover The abutting properties north and east
of the site, which include the wetlands, are used for hunting and select logging. The primary source
of drinking water in the area is private wells screened between 60 and 175 feet below ground surface
(bgs). within the surfkial sand and gravel aquifer.
B. SURFACE WATER
Large areas of wetlands have been mapped surrounding the site. Wetlands adjacent to the northeast
corner of the site are defined as forested, coniferous, wet soil, and palustrine. The wetland area
extends northeast and east of the site and is in hydrologic communication with other wetland types
and surface water bodies to the north and west. Within a four-mile radius of die site are
approximately 2,137 acres of lakes, 94 acres of bogs, and 7.500 acres of wetland. In particular,
Doctor Lake, and an unnamed lake, are located 2,000 feet east and northeast of the she. respectively,
and the 7,233-acre Amsterdam Slough Public Hunting Area is located one mile north of the site.
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C. GEOLOGY
The site stratigraphy can be divided into three stratigraphic layers: an upper sand, a glacial till, and
a lower sand.
The upper sand is fairly continuous across the site extending from the natural surface to depths of
90 to 120 feet. The upper sand consists of well-graded sand with some minor amounts (<10 percent)
of silt and clay, well-graded sand with silt, poorly graded sand, or poorly graded sand with gravel.
Discontinuous lenses of till up to 25 feet in thickness were encountered within the upper sand, at
depths of about 65 or 70 feet at three locations (MW02, MW05 and MW15).
The glacial till at PWP is of variable lithology. It consists mainly of silts, silty sands to sandy silts
with gravel. The unit is present beneath most of the site between elevations of 910 and 965 feet
mean sea level( msl) and ranges from 3 to 45 feet in thickness. The borehole data indicate that the
tills are lenticular and vertically as well as laterally discontinuous.
The till is underlain by poorly sorted sand and gravel that is similar in composition, texture and
depositional environment to the upper sand unit. The top of this lower sand unit was found at
elevations ranging from 978 msl in IT01 (102.5 feet bgs) to elevation 910 feet msl in MW17 (215
feet bgs). The full thickness of the lower sand has not been determined during any of the subsurface
investigations performed at the site. It extends to an elevation of at least 775 feet msl (300 feet bgs)
to the bottom of the deepest boring (MW18D). The lower sand may be interbedded with glacial till
layers at depths between 120 and 180 feet. The lower sand tends to fine upwards from poorly sorted
gravel, medium-to coarse-grained sand to silty sand. Where the till unit is missing, the lower sand
is usually indistinguishable from the upper sand and consequently, by convention, is described as
part of the upper sand. Regional maps indicate the Pleistocene deposits overlay Cambrian
sandstones and Precambrian basalt flows (WGNHS 1990). Geotechnical analysis of the upper sands
indicates the material has neutral to alkaline pH, low cation exchange capacity, and little organic
carbon in noncontaminated areas.
D. HYDROGEOLQGY
Ground-water at the PWP site occurs both in a thin unconfined aquifer and within a multi-layered
semiconfined aquifer system. In most areas of the site, the unconsolidated glacial deposits form a
deep unsaturated zone. The continuity of the consolidated till deposits determines two distinct
ground-water flow systems. Discontinuous consolidated till deposits of varying thickness have
caused semiconfined conditions. Till is absent and glacial deposits function as a single water-
bearing unit below the lagoon and near the PCP treatment area.
1. Unsaturated Zone
The site is situated in a ground-water recharge zone. Because of the high permeability of surficial
soils, precipitation rapidly infiltrates the soil. The depth to ground-water ranges from 20 feet in the
topographic low northeast of the lagoon (MW13) to greater than 150 feet south of Daniels 70
(MW15). Capillary moisture requirements are minimal in the unsaturated zone. Most of the soils
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were found to contain moisture near the saturation level (6 percent). Thus, water infiltrating from
the surface will have to satisfy only minimal capillary requirements before downward percolation
occurs. The unsaturated hydraulic conductivity probably approaches the saturated hydraulic
conductivity (19.3 ft/d) during a rain event. During dry weather, the unsaturated hydraulic
conductivity of sandy materials may be lower by three orders of magnitude (Hillel 1982).
Infiltration tests performed at two locations in the wastewater discharge gully found infiltration rates
relatively consistent (3.6 to 5.3 ft/day) throughout the entire depth of the borings with the exception
of IT01 (at 20 feet) which was found to have an infiltration rate of 200 ft/day. The later infiltration
rate is considered high even for an extremely sandy material
2. I Incnnfjined. Aanifrr
The unconfined aquifer consists of a thin zone of ground-water, within the upper sand unit, perched
upon the less permeable till. Beneath the lagoon and the PCP treatment area, the consolidated glacial
till deposits are discontinuous. At these locations, the unconfined and the underlying semiconfined
aquifers behave as a single unconfined system. The observed saturated thickness of the unconfined
aquifer ranges from less than 5 feet in MW06S to greater than 25 feet in MW18.
Ground-water elevation data were collected on 33 different occasions between March 25, 1 988, and
February 7. 1998. Based on the water level data, the observed ground-water elevations ranged from
a maximum of 994.5 feet msl at MW18 on September 8. 1994. to a minimum 979.83 feet msl in
MW06S on March 31, 1994. The ground-water levels in the unconfined aquifer have generally
increased over the monitoring period, with maximum elevations occurring in June 1997. The
maximum water level fluctuation observed in a single well over the entire monitoring period was
10 fee* in MW18. The fluctuations in the ground-water levels could not be correlated directly to
precipitation events. The lack of correlation was expected because of the time required for
percolation through the thick unsaturated zone and the frequency of measurements.
Avenge horizontal flow velocities were calculated using a range of horizontal hydraulic gradients
and an average hydraulic conductivity (2 1 ft/day) and assuming an effective porosity for the aquifer
matrix of 0.30. The horizontal velocities that were calculated based on these data range from 0.07
to 0.6 ft/day (25 to 2 19 ft/yr). This compares well to the estimation of ground-water velocity based
on the distribution of chloride. Chloride is a conservative indicator parameter because it travels at
the same rate as ground-water and does not undergo any degradation. Because chloride was
discharged to a pond outside the treatment building beginning in 1953, the distance chloride has
migrated can be used to estimate the ground-water velocity. Based on the chloride distribution, the
ground-water velocity is estimated to be about 25 ft'yr.
3. fopiicqnfined Aquifer
The semiconfined aquifer system consists of the ground-water within the lower sand unit. Twelve
wells and the production well (PW01 ) were installed in the uppermost portion of the semiconfined
system. Ground-water elevation data for the semiconfined wells were collected on 30 different
occasions between May 8, 1 990. and February 7. 1 998 Ground-water elevations range from 980.80
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feet msl in MW04 on March 28,1994, to 987.22 feet msl in MW03 on October 10, 1997. The water
levels in the semiconfmed aquifer also increased over time, similar to the trend seen for the
unconfined aquifer. The maximum water level fluctuation observed in a single well over the entire
monitoring period was 5.85 feet in MW03. Consistent with the unconfined aquifer system, the
fluctuations in the water levels could not be correlated to variations in precipitation.
Average horizontal flow velocities for the semiconfmed aquifer were calculated using a range of
horizontal hydraulic gradients and a geometric average hydraulic conductivity (7.6 ft/day), and
assuming an effective porosity for the aquifer matrix of 0.30. The horizontal velocities calculated
based on these data range from 0.01 to 0.1 ft/day (3.6 to 36 ft/year).
4. Ground-Water Flow Unit Interconnection
The water levels in the unconfined aquifer are generally a foot higher than measured in the
semiconfmed aquifer. The data suggest that the till, where present, is acting as a confining layer.
Water elevation data collected from three monitoring well pairs in the unconfined and semiconfmed
aquifers (MW18/MW05, MW10S/MW10, MW16/MW12) were compared to assess the hydraulic
connection between the two units. The limited data indicate strong downward vertical gradients
exist between the shallow unconfined and semiconfmed systems. The calculated vertical gradients
ranged from 0.008 to 0.045 ft/ft. The vertical gradients between the well pairs are about an order
of magnitude higher than the estimated horizontal gradients indicating a large vertical cornponem
to the ground-water flow. The strong downward vertical gradients suggest (hat the unconfined
aquifer may be discharging to the semiconfmed system in the area surrounding the lagoon.
VI. MAJOR FINDINGS - REMEDIAL INVESTIGATION AND RISK ASSESSMENT
In March 1998, the RI report for the PWP Site was issued (CH2M HILL 1998b). The nature and
distribution of contaminants at the PWP Site have been investigated since the early 1980s. Industrial
chemicals identified in the environment include both organic compounds and inorganic elements
associated with the PCP treatment process: PCP, its impurities and byproducts, the fuel oil carrier;
and compounds and elements associated with the ACZA treatment process: ammonia, copper, zinc
and arsenic. The most frequently detected contaminants at the PWP Site are PCP, arsenic, and
copper. Fuel oil is routinely assessed with the indicator parameters Total Petroleum Hydrocarbons
(TPH) or Diesel Range Organics (DRO). Compounds in addition to PCP that have been have been
detected in the ground-water above Wisconsin Preventive Action Limits (PALs) are benzene and
naphthalene. Arsenic, iron, and manganese concentrations in ground-water also exceed criteria,
but their presence is due to the high reducing and low pH conditions caused by oxygen utilization
by microbes degrading the PCP/oil in the ground-water. Soil arsenic found in the native aquifer
soils is solubilized from the soil media under reducing and low pH conditions. Select soil and
boiler ash samples analyzed for dioxins did not contain dioxin equivalent levels that exceed criteria
(U.S. EPA 1998).
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The PCP/oil mixture discharged on the surface has traveled to the ground-water and spread
horizontally as a LNAPL layer is in equilibrium with pore pressures, and is not expected to
continue spreading. POP concentrations in ground-water have been monitored at the site since
1988. and some of the wells have 1 1 rounds of sampling data. PCP ground-water concentrations
have shown consistent declines at the majority of monitoring wells over time, although many of
the wells have only been monitored for three years (Figure 4). There is a general decrease in the
size of the PCP plume, and the total contaminant mass of PCP in the saturated zone has declined
from 1994. Contaminated ground-water is not discharging to the wetland, or migrating below the
wetland to surface water bodies.
There is evidence that PCP is biodegrading in the ground-water by the natural attenuation
parameter data taken during select sampling events. The ground-water is under anaerobic
(reducing) conditions in both the unconfined and semiconfined aquifer in the LNAPL plume area.
Ground-water flow patterns at the she have changed since the closure of the production wells.
Horizontal ground-water movement is slow, on the order of 25 feet per year. PCP movement is
retarded by a factor of 3.5 in the saturated zone, due primarily to the presence of silts and clays
in the sand, as discussed later, resulting in PCP migration at an average rate of 7 feet per year.
Elevated chloride levels in wells are associated with elevated PCP content. However, chloride
levels cannot be directly related to PCP degradation because of the historical discharge of chloride
:o the boiler cooling pond. White anaerobic biodegradation can result in chloropbenol
intermediates that may accumulate, anaerobic dechlorination field studies that were conducted
/bund jo accumulation of intermediate breakdown products in water samples.
A. SOURCE APF.AS
Principle Threats:
1. Sftih-fHiHy in
The vadose zone soils within the two prominent arms of the gully leading from the oil/water
separator to the lagoon are contaminated widi PCP fuel oil mixture. This contamination is a result
of spills and discharge of contaminated wastewater from the oil-water separator building to the
lagoon. The ratio of PCP to TPH is about 5 percent, indicating that the PCP oil mixture is acting
as a single compound in the environment. In general. PCP concentrations are highest in the first
20 feet bgs where the wood debris layer has absorbed the PCP oil mixture like a sponge, then
drops until the 2 to 15 foot thick LNAPL smear zone is encountered. During test pit excavations,
an oily liquid was observed seeping into the pit from the wood debris layer.
2. LNAPL
As a result of the PCP/oil mixture draining from the surface to the water table, LNAPL is present
within a smear zone (i.e.. zone of water table elevation fluctuation) over an estimated 4-acre area
beneath the site. The LNAPL area is larger than the area of contaminated unsaturated zone mid-
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level soils (10 feet bgs to the water table), which is estimated to be 2.4 acres. This is a result of
lateral spreading of the LNAPL once it reached the water table.
The LNAPL exists both as a free phase (i.e., floating on the water table) and as a residual phase
(i.e. , held immobile at residual saturation between particles in the soil). LNAPL distribution is
significantly affected by water table fluctuations. As the water table rises, the mass of mobile
LNAPL is reduced, as LNAPL is entrapped at a residual saturation below the water table. After
the water table drops, LNAPL will drain back into the mobile LNAPL pool at the water table.
The LNAPL does not completely drain from the vadose zone soil pore spaces because of surface
tension effects. The LNAPL is a source of ground-water and soil contamination at the site.
The volume of LNAPL is the sum of the free-phase LNAPL and the residual-phase smear zone
LNAPL. LNAPL thickness measurements in wells MW10S, MW19, and MW20, from 1994 and
1997-1998, have shown measurable LNAPL ranging from less than 1 inch to over 10 inches thick.
LNAPL thickness measured in monitoring wells can overestimate the true thickness in the
formation. In one study, a sample of sandy soil similar to that at PWP, the actual thickness of
Mobile free phase LNAPL was near zero for measured thickness up to 3 inches in observation
wells. Another sandy soil had less than 0.2 inch LNAPL at a measured observation well thickness
of 9 inches (Fair et al. 1990). As a result, it is possible that free phase mobile LNAPL is
overstated at the site.
The residual-phase LNAPL in the smear zone extends both above and below the present water
table. The smear zone is estimated to be an average thickness of about 4 feet based on water table
fluctuations.
Low Level Threats:
I. Wood Chip Pile
The weed chip pile located in the northwest corner of the PWP site contains both PCP-oil and
metals contamination. The metals contamination consist of the ACZA components of arsenic,
copper and zinc. Arsenic at 440 ppm was found in a very localized area of the wood chip pile to
;wo feet deep. Zinc and copper were also found, but at levels below human health values. The
contamination is present as a result of process wastewater discharges. Wastewater was discharged
from ihe portable 300 gallon buggy five to six times per week for 6 to 7 years (i.e., approximately
450,000 gallons).
PCP and TPH have been detected in the wood chips at elevated levels of 1,300 mg/kg PCP and
24,000 mg/kg TPH from a depth of 4 to 7.5 feet, and 1 ,300 mg/kg PCP and 14,000 mg/kg TPH
at a depth of 16 to 17 feet. Elevated levels of PCP were detected from the 0- to 3-inch depth at
the southern toe of the wood chip pile, with concentrations of 520 mg/kg PCP, and 25,000 mg/kg
PCP. PCP was not detected in the center or northern portion of the pile. PCP concentrations
detected in soil boring samples from the wood chip/sand interface were minimal, with the
exception of 134 mg/kg at 14 to 15 feet bgs, located near a PCP concentration of 1,300 mg/kg at
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4 to 7.5 feet bgs. A ground-water grab sample collected in this area contained 6.2 ug/L PCP.
MW24 contains 4 ug/L PCP, while the subsurface soil sample collected during MW24 installation
at the wood chips and interface ( 1 7 to 1 9 feet bgs) contained 1 89 mg/kg PCP.
The PCP contamination is centered at the southern toe of the wood chip pile. Although significant
levels of PCP and TPH were found in the wood chips, the soil interface beneath the wood chips
appears minimally impacted. PCP in the wood chips ranged from 520 to 25.000 mg/kg. yet the soil
beneath the pile contained a maximum of only 189 mg/kg. Similarly, ground-water samples
collected at the water table in this area have minimal contamination.
2.
There are several locations on the site that have been contaminated by drippage from freshly treated
lumber, and by overland transfer of this drippage by sheet run-off during rain events.
B. FATE AND TRANSPORT OF SITE-RELATED CONTAMINANTS
Metals:
•\rsenic, copper and zinc, are immobile metals in the environment and have only been found in
surficial locations (to two foot depths), on the site. Overland transfer, through sheet run-off from
rain events, has distributed these metals into lower lying areas, primarily the wetlands north of the
lagoon. They are persistent in the environment, and will eventually be incorporated into vegetation
growing on the contaminated soil. They will not leave the site unless physically removed or
transformed to their soluble form under reducing conditions.
^cntachloropnenol/ruel oil:
I _ Chemical Properties
Fuel oil is a mixture of low molecular weight hydrocarbons, two of which are benzene and
naphthalene, compounds that contribute to both health based and environmental risks. Both benzene
and naphthalene have been found on site. Both are amenable to biological degradation at chemical
reactions rates greater than for PCP. They will be removed by biological activity well before the PCP
concentration has been reduced to Enforcement Standards (ES) or Prcventative Action Limits
(PALs). Soil residual contaminant levels (RCLs) for the fuel oil components are shown in Table 1 .
PALs for ground-water fuel oil components are shown in table 2.
Pure PCP is a solid and heavier than water. It is practically insoluble in water (5 mg/L at 5°C, 14
mg/L at 25*C. Vesala 1979). It must first be dissolved in an organic solvent to be effective for wood
treatment The solubility of PCP in #2 fuel oil exceeds 5 percent. The specific gravity of PCP
treatment mixtures is slightly above the specific gravity of *2 fuel oil ( 0.87 at 15°C; Kirk-Othmer
1980). so PCP dissolved in fuel oil floats on water. Once in the environment, the solubility of PCP
is further influenced by the pH of the soil or ground- water. PCP is considered a weak acid, meaning
its addition to water at any pH will not necessarily lead to full dissociation of hydrogen ion from the
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parent molecule. Specifically, PCP has an acid dissociation constant (pKJ ranging from 4.71 to 4.92
(Kirk-Othmer 1984) at 25°C. The pKa indicates the pH at which 50 percent of a weak acid will be
dissociated. As a rule of thumb, systems with pH levels in excess of the pKa by 2 Standard Units
(S.U.) provides complete dissociation. For instance, an aqueous system with pH 6.8 will provide
complete dissociation of PCP to its anion, pentachlorophenolate. This sodium salt of PCP has a
solubility of 22,400 mg/L, a dramatic increase compared with the PCP molecule. Based on the latest
ground-water sampling, the average ground-water pH is 7.16, and the average ground-water pH in
the wells with LNAPL is 7.89. At these pHs, PCP is completely dissociated. As observed, this
results in ground-water concentrations of PCP much higher than possible for pure PCP.
Solubility and sorption potential are strongly correlated (Chiou 1979). Researchers have found that
sorption of the PCP molecule to mineral surfaces (clays) is 50 times greater than sorption of the
pentachlorophenolate. A relative index of sorption is provided by distribution coefficients (Kj). A
site-specific Kj of 17.2 was developed for the PWP site from soil washing treatability studies (Roy
F. Weston 1994a) for unsaturated zone soils. This high Kj indicates that PCP, as it exists in the oil
phase, will not readily leach from the soil.
2. Migration Pathways
PCP was introduced to the environment through the discharge of wastewater containing the PCP/
No. 2 fuel oil mixture from the oil/water separator into the gully and lagoon areas, the wood chip pile
area, and other isolated areas. From the surface, the PCP traveled as a single phase with the No. 2
fuel oil to the ground-water table, where it spread horizontally as a LNAPL layer, until equilibrium
with pore pressures was reached. Absent further LNAPL release, or changes in ground-water
gradients, the LNAPL is not expected to continue spreading horizontally. The LNAPL acts as a
continuous source of PCP to the ground-water. Within the saturated zone a site-specific Kd of 0.6
L/Kg was estimated based on a soil organic carbon of 0.04 percent. This indicates that the PCP is
not as tightly bound to mineral surfaces as in the unsaturated zone.
Vertical migration of the LNAPL through the unsaturated zone is believed to have ceased. This is
based on the lack of a substantial continuing source of pure phase LNAPL and the retention capacity
of soils for fuel oil. The retention capacity of sands for light fuel oils is 4 percent of the soil volume
(Dragun et al. 1991). TPH values in the contaminated soil of the unsaturated zone are much less
than this value. Three samples from within the wood chips exceed 40,000 mg/kg (4 percent) TPH,
although wood chips would be expected to have a much higher retention capacity. Slow releases
of LNAPL from the wood chips would be retained in the sand, if the sand is below its retention
capacity.
Dissolved phase PCP releases from the wood chips are expected to continue. However the rate of
downward transport is minimal for PCP because of its high adsorption capacity (Kj = 17.2), and sand
below its retention capacity. The more significant release mechanism for PCP is the dissolving of
PCP from the LNAPL as phenochlorophenolate.
Migration pathways for the PCP in ground-water is generally expected to be in a radial pattern
outward, and over a period of time in all directions, at a very slow rate. The flow directions are
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difficult to determine precisely from ground- water elevation data because the gradient is minimal.
However, based on the distribution of the chloride and PCP contamination, it appears migration has
occurred in all directions at roughly similar rates. It does appear that there will be less migration in
the southwest direction as a result of the shut down of the water supply well PW-01 in May 1992.
To the north, ground-water in the unconfined aquifer will eventually discharge to the wetland area.
Overland transport of contaminated soil and the PCP 'oil mixture is another significant pathway,
particularly in the northeast corner of the site. The northern wall of the lagoon is collapsing and
wood debris from the site and fuel oil have been observed in the adjacent wetland.
3.
Contaminant fate processes for PCP in the subsurface include hydrolysis, volatilization, dispersion,
adsorption, and biodegradation. Surficial soil and surface water PCP contamination can also be
degraded by sunlight
The rate of hydrolysis of PCP in the ground-water is not known. It is not expected that hydrolysis
plays an important role in the destruction of PCP. PCP is considered a semi volatile, with a vapor
pressure about four orders of magnitude less than that of volatile organic compound (VOC). As a
result, volatilization of PCP is not a significant loss mechanism. Dispersion, the process by which
concentrations are reduced as a result of horizontal and vertical spreading, will result in further
reductions in PCP concentrations. Adsorption of PCP also occurs, which is dependent ori its
solubility and the soil organic carbon content. PCP is adsorbed on the organic and on the mineral
portions of the soil, both significant mechanisms for retarding PCP migration. Solubility of PCP
is dependent on the pH as discussed above. Within the ground-water the fraction of organic matter
is considerably less than the unsaturated soils, resulting in a much lower K* of 0.6 L/Kg. and much
less adsorption. Because adsorption is a reversible process, it is not considered a remedial
mechanism. It does provide additional time for natural processes to occur, however.
A Kj of 0.6 L/Kg for PCP in the saturated zone results in a retardation factor of 3.5. At an average
ground-water velocity of 25 ft/yr, PCP is expected to migrate at 7 ft/yr. The estimated PCP
migration velocity based on the travel distances from die perimeter of the LNAPL, and assuming the
presence of LNAPL in 1960. is 10 ft/yr (based on a distance of 400 feet in 38 yrs). The estimates
of migration velocity compare reasonably welt. Travel times for migration of PCP from the
perimeter of the plume to the nearest residential wells, a distance of about 400 feet, is on the order
of 40 years. PCP has been detected once in a residential well at 2 ug/l. which is above health based
Enforcement Standard in NO 1 40 Wisconsin Administrative Code. A duplicate sample on the same
day was below the quantitation level. Subsequent sampling of this well on several occasions has
cot delected PCP or fuel oil constituents.
Estimates of contaminant travel times are subject to a high degree of inaccuracy because of the many
simplifying assumptions. Of particular importance is the estimate of hydraulic conductivity and the
K* both of which can vary by an order of magnitude within short distances within the sand aquifer.
Actual travel times may be considerably different than the estimated average values presented.
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This estimated travel time does not consider contaminant degradation. Given the long travel time
for PCP to reach the ground-water and the relatively slow PCP migration velocities in ground-water,
biodegradation is a significant loss mechanism. Biodegradation is the process by which
microorganisms consume the PCP, either as a primary substrate or as an electron acceptor.
Biodegradation of PCP may occur anaerobically or aerobically with rates generally expected to be
more rapid aerobically.
Anaerobic biodegradation occurs by reductive dechlorination, a process in which the chlorine atoms
are sequentially replaced with hydrogen (PCP to tetra chlorophenol to trichlorophenol to
dichlorophenol to chlorophenol to phenol). Abiotic reductive dechlorination may also occur as
microorganisms can release organ-metallic cofactors into the subsurface environment to catalyze the
dechlorination reaction (Smith et al. 1994). Aerobic degradation pathways are less certain, although
it appears that an initially hydroxyl group substitutes for a chlorine atom. Once the aromatic ring
has two hydroxyl groups, the ring can be cleaved and then mineralized to carbon dioxide and water.
Few intermediates other than chloride have been shown to accumulate (Rochkind, et al., 1986).
Biodegradation rate constants vary considerably in the literature. Aerobic half lives range from
0.8 days to 51 days.
Anaerobic half lives are more pertinent to the unsaturated zone at PWP because the high TPH
concentration has resulted in sufficient biological activity to utilize the available oxygen and produce
anaerobic conditions. Anaerobic half lives are more limited in literature and range from 6.1 days
to 266 days (Pelorus Environmental & Biotechnology Corporation 1997). Site-specific aerobic half
lives developed for treatability studies were generally on the order of 30 days (Roy F. Weston
VII. SUMMARY OF SITE RISK
A Baseline Risk Assessment was conducted to evaluate potential risks from contaminant exposure
at this facility, and determine the need for and extent of remediation. A Focused Human Health Risk
Assessment Report (Ecology & Environment 1997) and a Screening Level Ecological Risk
Assessment Report (CH2M HILL 1998a) were prepared. The risk assessments were conducted in
accordance with U.S. EPA's guidance, including: " Risk Assessment Guidance for Superfund: Volume
1 Human Health Evaluation Manual" (U.S. EPA 1989); "Risk Assessment Guidance for Superfund:
Volume I Environmental Evaluation Manual, Supplemental Guidance, Standard Default Exposure
Factors; Part B, Development of Risk-Based Preliminary Remediation Goals " (U.S. EPA 1991); and
Risk Assessment Guidance for Superfund: Process for Designing and Conducting Ecological Risk
Assessments (U.S. EPA 1997). These documents provide the methodology and standard assumptions
used for evaluating risk and developing appropriate cleanup standards.
A. OBJECTIVES
The specific objectives of the baseline risk assessment for the PWP Site facility were to provide:
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an evaluation of potential human health and ecological risks and a basis for
determining the need, as required, for remedial action at this facility;
a basis for determining the appropriate remedial target cleanup levels for
contaminants in soils, ground-water, sediments, and/or surface water, as necessary;
and
a basts for comparing the health impacts of various proposed remedial alternatives
B. HUMAN HEALTH
The Human Health Risk Assessment for the PWP Site is a quantitative evaluation, conducted in
accordance with U.S. EPA and state guidance, and consists of the following components:
Hazard Assessment;
Exposure Assessment;
Toxicity Assessment;
Risk Characterization; and
Discussion of Uncertainty.
The Human Health Risk Assessment for the PWP Site indicates that the ground-water contaminant
concentrations result in carcinogenic and non-carcinogenic risk estimates greater than the U.S. EPA
target risk range. Site soil concentrations also resulted in carcinogenic and non-carcinogenic risk
estimates greater than the U.S. EPA target risk range.
I.
The Focused Human Health Risk Assessment (FHHRA) was prepared using the characterization
data from the Emergency Response Team (ERT) investigation conducted in 1994 (Roy F. Weston
1994 and 1995). Exposure concentrations used in the FHHRA were based on pre-removal action
concentrations, and were not adjusted after highly contaminated soil was removed from the site in
19%, so they should be viewed as high-end estimates. The objective of the FHHRA was to evaluate
potential adverse health effects associated with site-related contaminants in the absence of remedial
action. Consistent with the SACM approach, constituents of potential concern (COPCs) were
determined by WDNR and U.S. EPA and the FHHRA focused on POP, arsenic, copper, zinc, and
dioxins/furans. Dioxins/furans were qualitatively evaluated (Ecology & Environment 1997).
Preliminary remediation goals (PRGs) based on concentration levels corresponding to an excess
cancer risk between 1x10* to I x 10"* . and/or a chronic health risk defined by a hazard quotient of 1
were developed for soil and ground-water for an expanded list of COPCs in the Feasibility Study
(CH2M HILL I998c). Table 1 presents COPCs for soil and compares human health and ecological
PRGs with other appropriate federal and state criteria. These criteria include the human health based
Wisconsin NR 720.11 RCL. and the soil concentration protective of ground-water. The latter
identifies the contaminant concentration that can be left in the soil that will not exceed Wisconsin
PALs if the contaminant leaches into the ground- water.
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%^f Table 2 presents COPCs for ground-water and compares risk-based levels with Wisconsin PALs.
ES and Federal Maximum Contaminant Levels (MCLs).
2. Exposure Assessment
The purpose of the Exposure Assessment is to estimate the type and magnitude of potential exposure
to constituent of potential concern (COPC) at or migrating from the PWP Site based on site-specific
conditions. Exposure is quantified by calculating exposure doses for each exposure scenario.
Exposure doses are calculated based on the exposed populations, exposure point concentrations, and
exposure pathways using the equations and default values presented in U.S. EPA and state guidance
(U.S. EPA 1988, 1989a, 1991). Exposure and risk estimates were generated by using conservative
(health-protective) reasonable maximum exposure (RME) and average exposure values. The average
case represents exposure that is most likely to occur for most of the potentially exposed population,
and is evaluated with the RME case to provide a range of risk estimates. The exposure assessment
focused on potential future uses of the site and conservatively included residential exposure
scenarios as well as industrial and construction/excavation worker. Exposure and risks were
estimated for both "general" site residents and workers (assuming random exposure across the site),
and treatment area residents and workers (assuming that a residence or workplace is located in the
treatment building area). The PWP Site was industrial, and it is expected that future uses will remain
industrial. The property northeast of the site that contains the impacted wetland is used for hunting
and logging. The two residential wells nearest the site are located south of Daniels 70; one well
serves a farm with a small herd of beef cattle. Table 3 presents a summary of the media evaluated,
\iif exposed population and complete exposure pathways, and cancer and non-cancer risks for the on-'jite
general area and the treatment area.
3. Toxicity Assessment
The toxicity assessment provides information regarding the potential for a specific COPC to cause
adverse effects in humans, and characterizes the relationship between the dose of a chemical and the
incidence of adverse health effects in the exposed population This assessment, therefore, identifies
a dose-response value that can be used to quantitatively evaluate potential health risks as a function
of chemical exposure.
Carcinogens
Carcinogenicity is quantified by the cancer slope factor (CSF). The CSF is U.S. EPA's upper-bound
lifetime probability of an individual developing cancer as a result of a lifetime exposure to a
carcinogen. CSFs are determined by U.S. EPA and published in an integrated risk information
system (IRIS, 1998b), an on-line database for toxicity data, and health effects assessment summary
tables (HE AST, 1998c). A summary of the oral dose-response information for carcinogenic effects,
including the CSFs, for each COPC is provided in Appendix E of the FS report (CH2M HILL,
1998).
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Non-Carcinogens
Non-carcinogens are those compounds that cause an effect (e.g., liver damage) other than
carcinogenichy. Carcinogens may also have non-carcinogenic effects: these effects are considered
and included with the effects of non-carcinogenic compounds. In addition, non-carcinogenic
compounds differ from carcinogens in that they are believed to have threshold dosage levels below
which adverse effects are not expected. U.S. EPA's preferred criterion for quantifying non-
carcinogenic risk is the reference dose (RfD). which corresponds to U.S. EPA's identification of the
threshold effects level with an added margin of safety. The IRIS database maintains a current listing
of all the verified RfDs. which are reported in units of mg leg-day. By definition, the RfD is an
estimate of an average daily exposure level below which significant, adverse non-carcinogenic health
effects are not expected. Appendix E in the FS report presents the chronic RfDs and oral dose-
response information for non-carcinogenic effects for each COPC. Toxicity profiles for the COPCs
are available from the IRIS database.
4.
The Risk Characterization integrates the quantitative exposure and toxicity values for each exposure
scenario. Table 3 presents a summary of the quantitative summary of site risk.
Carcinogenic Effects
Carcinogenic risks are evaluated by multiplying the estimated exposure dose by the CSF to obtain
an estimate of incremental risk, as follows:
Carcinogenic Risk = Exposure Dose (mg/kg-day) x CSF (mg/kg-day)'
The cancer risks of each compound are summed within each exposure scenario. U.S. EPA's
guidelines state that the total incremental carcinogenic risk for an individual resulting from exposure
at a hazardous waste site should not exceed a target risk range of IxlO* to lxlO->(U.S. EPA 1990).
In mis risk assessment, the estimated carcinogenic risk for each exposure scenario was compared to
these values. If the estimated risk is below the acceptable range, no further action is recommended.
If the estimated risk is within the acceptable range, the exposure scenario is reviewed to determine
whether further actions are warranted, depending on where the estimated risks fall within that range.
Further actions are recommended for estimated risks exceeding the upper end of the target risk range
(IxlO-1).
Non-carcinogenic Effects
Non-carcinogenic effects are quantified in terms of a Hazard Index (HI), which is calculated by
dividing the exposure dose by the RfD:
Hazard Index (HI) = Exposure Dose (mg/kg-day) ' RfD (mg/kg-day)
Non-carcinogenic risks are evaluated by dividing the exposure dose of each compound by its
respective RfD. and summing the resulting hazard index for each compound within each exposure
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scenario. The resulting cumulative non-carcinogenic risk for each exposure scenario was compared
to the U.S. EPA target HI of 1. If the HI is less than or equal to 1, no adverse health effects are
anticipated from the predicted exposure dose level. If the HI is greater than 1 , the predicted exposure
dose level could potentially cause adverse effects (U.S. EPA 1989a). Table 3 presents a summary
of the carcinogenic and non-carcinogenic risk estimates for each exposure scenario.
5. Summary of Human Health Risk Assessment
Based on the PWP Site conceptual model developed in the RI, four media at and surrounding the
PWP Site were identified as the focus for the human health risk assessment:
Soil;
Ground-water;
Outdoor Air; and
Homegrown Produce.
Soil
Based on the results of this risk assessment and anticipated future use of this land, remedial action
is necessary to protect human health due to contaminants present in surface and subsurface soils.
Subsurface soils require remediation to limit leaching of contaminants to the ground-water.
Contamination in soils has also extended off the PWP property along an alluvial fan ending in the
wetland. A site-specific quantification of potential risks was calculated using an adult resident, a
typical worker, and a construction/excavation worker scenarios. The estimated carcinogenic and
lion-carcinogenic risks were well above U.S. EPA target risk ranges in the treatment area, and within
the target risk range for the sitewide soils. At each exposure point where a receptor may come into
contact with known or potentially contaminated media, exposure point concentrations (EPCs) are
determined for each COPC. For the PCP data, the 95 percent upper confidence limit (UCL) on the
mean chemical concentration of the data set was used as the EPC. For the metals data, relatively few
detections were observed in the samples. A probability plotting method was used to fit the data to
a lognormal distribution above the detection limit and then extrapolate to values below the detection
limit. The extrapolated values and detected values were combined to compute the 95 percent UCL.
Areas of soil exceeding U.S. EPA target risk ranges, and WDNR soil RCLs and soil concentration
protective of ground- water are shown in Figures 2-1 through 2-4 of the FS report. PCP and arsenic
are the principal threats driving the remediation; the other COPCs are within the PCP and arsenic
areas. The IxlQ-6 U.S. EPA industrial site worker cancer risk PRO, and the WDNR Non-residential
RCL for arsenic are lower than regional background levels for arsenic. A site-specific background
arsenic level will need to be determined.
Ground-Water
Ground-water is the sole drinking water source in the area. The risk assessment indicates that PCP
ground-water contaminant concentrations result in carcinogenic and non-carcinogenic risk estimates
greater than the U.S. EPA target risk range, based on residential drinking water scenarios.
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Contamination in ground-water has been detected off site at one occasion at one residential well, and
at the perimeter of the property. Future potential receptors were assumed to be residents using the
on-site ground-water for drinking water. Drinking water exposure could be via ingestion or dermal
contact with the ground-water.
A site-specific quantification of potential risks was calculated for ground-water using the residential
drinking water scenario, and are summarized in Table 3. The estimated carcinogenic and non-
carcinogenic maximum calculated risk and Hazard Index are 1.4x10*'and 100 respectively. The
results of the qualitative human health risk assessment indicate that over 99 percent of the risk is
from PGP. Other COPCs that have been delected at or above federal drinking water standards, and
NR 140 Enforcement Standards, are benzene (in 2 wells), naphthalene (in 4 wells), and arsenic (in
1 well). Elevated levels of iron, manganese, and chloride that exceed public welfare taste or odor
aesthetics criteria are also present in ground-water, the arsenic, iron, and manganese are present as
a result of reducing conditions in the LNAPL area that are solubilizing native metals from the soil.
Chloride is elevated from the discharge of water softener salt and as a result of PCP degradation.
Outdoor Air
Based on the results of the risk assessment, no remedial action is necessary to protect human health
relevant to inhalation of outdoor air at the s te. even within the treatment area with a future
residential land use.
Homegrown Product . •
The risk assessment indicates that contaminant concentrations present sitewide would result in
carcinogenic risks at 5.5x 1O^5 for the ingestion of homegrown produce by residents. Contaminant
concentratiorts in the treatment area result in carcinogenic and non-carcinogenic risks that exceed
U.S. EPA target risk ranges for the ingestion of homegrown produce.
C. ETOLOGir Al. RISK ASSESSMENT
The objective of the Screening Level Ecological Risk Assessment is to evaluate the current and
future potential ecological risks that may exist at the PWP Site in the absence of any remedial action.
The risk assessment process follows procedures as described in Ecological Risk Assessment
Guidance far Superfund: Process for Designing and Conducting Ecological Risk Assessments. Final
(U.S. EPA 1997). Risk is characterized on the basis of several conservative exposure assumptions,
utilizing maximum concentration data. A problem formulation phase served to develop a conceptual
model of she contaminants, potential exposure pathways and receptors. The outcome of the problem
formulation phase was the identification of appropriate assessment and measurement endpoints for
the quantitative risk assessment. COPCs were identified, and ecological effects data was assessed
to develop ecological exposure estimates for each representative receptor of concern. Hazard
quotients (HQs) were calculated which compare point estimates of ecotoxicity values to exposure
values for each receptor based on food, soil, and surface water ingestion. As the HQs generally
greatly exceeded 1. ecological PRGs for the COPCs were developed in the FS report. The PRGs
were also compared to federal and state environmental criteria or guidance levels.
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1. Problem Formulation
W
The environmental setting of the PWP Site consists of a hardwood and coniferous forest, with
numerous water bodies and associated wetlands nearby. On and immediately adjacent to the PWP
site are three distinct community types; upland scrub/grassland (previously active portion of the site),
upland mesic/dry mesic forest, and forested wetland. Areas of significant aquatic habitat are not
present immediately adjacent to the site. Contaminated soils or sediments have been detected in
each of the community types. Ground-water is located from over 100 feet below ground surface at
the southern portion of the site to the surface water interface where it discharges to the wetland.
Contaminated ground-water is not accessible to ecological receptors, as contaminated ground-water
does not extend to the wetland. Surface water in the wetland is contaminated as a result of overland
transport of contaminated material. The same COPCs identified for the FHHRA were used as
ecological COPCs, i.e., PCP, arsenic, copper, and zinc.
Receptors may be exposed to site contaminants through routes that include incidental ingestion of
surface soil, sediment and surface water; direct contact with surface water, sediments and surface
soils; and possible inhalation of soil particles. Use of contaminated wood chips for nest building
may also bring bird species in direct contact with contaminants. Ground burrowing may also bring
mammals in contact with contaminated materials.
Plants growing on and adjacent the PWP site may come into direct contact with soil-associated
contaminants. Aisenic and PCP are both known to be phytotoxic. Some indication of phytotoxicity
is already present on and adjacent to the site.
Ingestion of food items which may have accumulated site-related contaminants may represent an
exposure pathway, however this exposure route is considered less likely given the nature of
contaminants present. Arsenic is taken up by plants through the root system, but typically not at
levels that are toxic to consumers such as herbivores. PCP in soil can also be taken up by root tissue,
however, translocation to the inner portions of the plant are negligible (Ecology and Environment
1997). As a result, food chain transfer of site-related contaminants through plants is not considered
significant. In contrast, PCP bioaccumulation in earthworms has been demonstrated to range from
3.4 to 13 for uptake of PCP adsorbed to soil particles, with much higher values reported for tests on
the basis of PCP in soil solution (ASTDR 1994). PCP is rapidly excreted, however, and there is little
tendency to persist in tissue (Eisler 1989). This tendency may limit the potential for food chain
transfer to secondary consumers such as small mammals and birds.
Although PCP is known to bioaccumulate in aquatic organisms it is not known to biomagnify. There
is also limited evidence of bioaccumulation of the compound in the aquatic food chain, as it does
not persist in living tissue (ASTDR 1994). The limited amount of aquatic habitat on or adjacent to
the site would preclude bioaccumulation in fish as a significant exposure pathway.
•
Wildlife species known in Burnett County include 94 breeding bird species, 35 reptile and
amphibian species, and 72 species of mammals. The representative receptor species chosen based
on the exposure pathways of concern and the amount and quality of toxicity information available
i, A for the receptor were deer mouse, short-tailed shrew, raccoon, and American robin.
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2. pvgjygiion of Protected Species in Burnett County
The U.S. Fish and Wildlife Service (FWS) identified three rare, threatened, or endangered species
known to occur in Burnett County: the bald eagle, gray wolf and Karner blue butterfly. The FWS
concluded that none of the listed species are expected to be affected by the site (Attachment A,
Ecological Risk Assessment). The WDNR identified three threatened bird species (bald eagle,
osprey, and red-shouldered hawk) and one endangered plant species (sand violet). The on-site
communities are not expected to provide significant habitat area for the animal species. Although
a site specific survey has not been conducted, the disturbed condition of the PWP site makes the
presence of the sand violet unlikely.
3. Effects p,YfllU8tlftH flild Exposure Estimates
Screening level ccotoxicity values for each contaminant of concern at PWP was developed from the
available literature. When possible, screening ecotoxicity values represent a no-observed-adverse-
effect-level (NOAEL) determined through long-term (chronic) exposures scenarios. If NOAELs
(preferred) were not available then lowest-observed-adverse-effect-level (LOAELs) were used with
a correction factor of 0. 1 applied. If LOAELs are not available then LCM or ECM values were
reviewed for appropriate application to this risk assessment.
Table 6 in the Ecological Risk Assessment report summarizes the toxicity information on arsenic,
copper, zinc, and PCP considered to be suitable for risk* characterization given factors such as test
duration, test species and stale or formulation of test material. From this information screening
ecotoxicity values were developed for use in risk calculations. When appropriate, correction factors
were applied to derive a specific NOAEL value.
Exposure estimates were calculated (or each receptor of concern at PWP. Ingestion was considered
the primary route of exposure of site contaminants to potential receptors. Exposure estimates in the
form of an exposure dose were calculated for each receptor and contaminant. Exposure doses were
was derived by multiplying the ingestion rate for the test species by the maximum observed
concentration of a contaminant (in nog/kg).
Estimates of body weight and food ingestion rates of receptor animals were obtained from USEPA's
Wildlife Exposure Factors Handbook (USEPA 1 993 ) Rates of incidental soil and water ingestion
for each receptor were also developed following the USEPA approach as described in the Handbook.
4. Ecologcal
The HQ approach, which compares point estimates of screening ecotoxicity values and exposures
values, was used as the primary approach for Risk Characterization. Screening ecotoxicity values
are equivalent to a documented and/or best conservative estimated chrome NOAEL. Thus, for each
contaminant and environmental medium, the hazard quotient is expressed as the ratio of a potential
exposure level to the NOAEL. An HQ less than one (unity) generally indicates that the contaminant
alone is unlikely to cause adverse ecological effects. Hazard quotients were calculated for each
receptor under each of the four exposure scenarios using the following equation:
-------
HQ = exposure point concentration/adjusted toxicity reference concentration
HQ values for each receptor based on food, soil, and surface water ingestion at PWP are presented
in Table 4. Calculations of exposure levels for each of the four receptors under each of the four
exposure scenarios resulted in several HQ values which exceeded one (unity).
Erosion and drainage from on-site areas into surrounding woodland and wetland has resulted in
elevated levels of PCP and arsenic within the wetland area. The risk appears greatest from exposure
to PCP and arsenic, with lesser .risk levels associated with copper or zinc. These elevated levels
appear to represent a risk to ecological receptors inhabiting areas adjacent to the site. As habitat
quality in these areas can be considered relatively high, the potential for receptor exposure can also
considered relatively high.
Additional characterization of potential ecological risk at PWP can be made based on comparison
of contaminant concentrations with available media-specific criteria or benchmarks. Although
aquatic habitat sufficient to support fish and a diversity of aquatic invertebrates is generally lacking
on or immediately adjacent the site, wetlands down gradient of the washout gully may support some
aquatic or semi-aquatic species. Several existing benchmark or criteria for COPCs in sediments and
surface water are summarized in Tables 5 and 6, respectively.
Contaminant concentrations in the sediment and surface water were compared to available criteria
or benchmarks as an additional characterization of potential risk at the site. Contaminants detected
at concentrations above available benchmarks may be considered to represent additional risk to
receptors at the site. Maximum concentrations of PCP and arsenic in surface waters collected from
the off-site wetland exceed chronic water quality criteria. Benchmark values for PCP, arsenic and
copper in freshwater sediments are also exceeded.
5. Summary of Ecological Risk Assessment
Based on the screening level risk assessment, subsequent development of a range of site-specific
PRGs, and the comparison of contaminant concentrations to the site-specific PRGs and established
federal and state criteria, it is concluded that the contaminant concentrations on-site, and off-site in
the wetland pose a threat to the environment. Table 5 and Table 6 summarize the PRGs for COPC
in sediment and surface water, respectively.
VIII. REMEDIATION OBJECTIVES
Pentachlorophenol and arsenic are the primary risk drivers at the site. Pentachlorophenol is present
in soils down to ground-water, is a major component of the LN APL, and is present in the ground-
water plume. Arsenic is present primarily in surface soils and in wetland sediments.
Pentachlorophenol: The remedial objective is to reduce the PCP content in soils and ground-water
to achieve compliance with ch. NR 720, Wisconsin Administrative Code, and in ground-water to
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achieve compliance with PALs. as established in ch. NR 140. Wisconsin Administrative Code,
within a reasonable period of time, by removing the free phase LNAPL, and associated highly
contaminated ground-water, remediating the PCP in the soils, and monitoring the intrinsic
remediation of PCP in the ground-water. Provisions will be installed to reduce direct contact
exposure potential during the remedy. Site erosion control systems will also be constructed.
;: Highly contaminated arsenic soils will be immobilized and consolidated with other arsenic
contaminated soils (above background), and secured, to achieve compliance with ch. NR 720. Soil
contaminated with arsenic and other metals will be managed to essentially eliminate the direct
contact exposure route and to protect ground-water. Performance of the metals consolidation area
will be monitored.
Erosion Controls: An Erosion Control Plan will be implemented and maintained to prevent physical
transport of contaminatinanon off-site and to protect the cap and consolidated areas from damage.
The erosion control measures will be periodically inspected, and repaired as necessary.
These remedial actions will prevent the potential for future human health and environmental risks
associated with exposure to PCP. rod oil components, and metals in the soil, sediment, and ground-
•.vcter by (h removing die ongoing source of PCP to the ground-water (2) reducing residual PCP/oil
concentrations in the smear zone and vadose soils (3) immobilizing the metals-contaminated soils
(4) eliminating the exposure pathway to die metals-contaminated soils; (5) eliminating die exposure
pathway to PCP/oil-contaminated soils and sediments while they are biodegrading (6) eliminating
overland flow of contaminated materials to the wetland and (7) restoring the ground-water to PALs.
IX DESCRIPTION OF ALTERNATIVES
Thirty four potential remedial technologies were identified in die FS Report (Tables 3-1 through 3-3
of the FS). Seven options were retained for detailed analysis for the soil media, five options were
retained for detailed analysis for the LNAPL. and nine options were retained for detailed analysis
for the ground-water media. These remaining technologies were assembled into five soil alternatives
and five ground-water/LNAPL alternatives that range from No Action (used as a baseline to compare
with the other alternatives) to containment to permanent treatment Soil alternatives were combined
with ground-water/LNAPL alternatives and five alternatives were selected for the Proposed Plan and
are discussed below. Table ? presents the key components of each alternative.
A. ALTERNATIVE 1 - NO ACTION
This alternative was developed and evaluated in the FS to serve as a baseline with which to compare
the other remedial alternatives For the No-Action Alternative, no institutional controls would be
implemented and no remedial actions would be conducted. This alternative would not implement
institutional controls to prevent the potential for future exposure to contaminated ground-water, soil,
sediments and surface water and would not include remedial action statutory and regulatory
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requirements to reduce ground-water contaminant concentrations to PALs. Off-site transport of
||yl PCP- and metals-contaminated soil to the wetland would continue.
Given the 4-acre LNAPL area that contains an estimated 550,000 gallons of residual-phase and free-
phase LNAPL, continual loading of contaminants to the ground-water would likely occur for
hundreds of years. It is unlikely natural attenuation processes would reduce PCP concentrations in
the center of the LNAPL area to PALs within a time frame regarded as reasonable.
Estimated Time to Design and Construct = No remedial activities required
Estimated Remedial Time Frame = Hundreds of years
Estimated Capital Cost = $0
Estimated Operation and Maintenance Costs (net present worth) = $0
Estimated Total Cost (net present worth) = $0
B. ALTERNATIVE 2 - SOIL CONSOLIDATION AND COVER WITH SOIL.
NATURAL ATTENUATION. GROUND-WATER AND LNAPL COLLECTION AND
TREATMENT AND MONITORED NATURAL ATTENUATION OF GROUND-
WAIER
In this alternative, soil remedial objectives are met through prevention of direct contact to soils,
preventing continued erosion of contaminated soils and allowing natural processes to reduce the PCP
in soil. Small isolated areas of PCP-and arsenic-contaminated soil, will be excavated and
itJ consolidated over the LNAPL area. This area will be covered with 1 foot of clean soil and
vegetation established. Figure 5 presents the layout of the soil cover.
Ground-water remedial objectives are met by removing the free phase LNAPL and treating the
grossly PCP-contaminated ground-water plume. The remainder of the PCP plume will be restored
by natural attenuation, consistent with ch. NR 140 standards, within a reasonable period of time.
LNAPL removal will consist of isolating and collecting the LNAPL and storing it. It will then be
sent off site to a RCRA compliant incinerator for disposal. Ground-water treatment will consist of
contaminant removal (VOC, semivolatiles, PAH) by carbon adsorption. The treated ground-water
will be discharged on-site through infiltration galleys, or by use of injection wells, in accordance
with the substantive requirements for a WPDES permit and section NR 140.28, Wisconsin
Administrative Code, outside the area of soil and ground-water contamination. Pore exchange
modeling estimates show that over 90 percent of the PCP in the ground-water would be removed
after 5 years (Appendix F of the FS).
This alternative would consist of the following components:
Building demolition
Solidification of highly contaminated arsenic soils
Segregation and placement of other arsenic soils above background in a C AMU
Consolidation of PCP/fuel oil soils and wood chips under a soil cover
* A • Bioventing PCP/fuel oil contaminated material
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Biopad removal and backfill on-site
Erosion control measures
Revegetation
LNAPL removal
Grossly contaminated ground-water collection, treatment and discharge
Monitored natural attenuation
Institutional controls
Environmental monitoring/maintenance
Point-of-usc carbon treatment, if necessary
Five-year site reviews
!. Ruilding Demolition
Existing buildings will be demolished. This includes the former PCP treatment building and the
oil/water separator building. Asbestos may be of concern in the former treatment building, which
may increase demolition costs. Demolished buildings would be disposed of in a nearby solid waste
landfill, salvaged, or used for on-site fill, if the demolition debris is below Toxicity Characteristic
Leaching Procedure (TCLP) for arsenic and PCP. Debris that contains PCP or arsenic above TCLP
levels for arsenic and PCP. will be disposed of either in a special waste landfill or a hazardous waste
landfill.
2. Solldificatiftn 01'Arsenic Soils
The objective of this component is to excavate arsenic-contaminated soils, treat the grossly
contaminated soils using solidification, and dispose on-site in an area separated from the organic
contamination. The area of soil contamination will be designated as a Corrective Action
Management Unit (CAMU) in accordance with ch. NR 736. Wisconsin Administrative Code, to
allow consolidation of soils containing listed hazardous waste without triggering Land Disposal
Restrictions (LDRs). Since both the ch. NR 720 Non-industrial and Industrial Direct Contact
Residual Contaminant Levels (RCLs) are at or below background, arsenic-contaminated soils
exceeding background (to be established) will be consolidated in the metals disposal area. Previous
investigations at the site have shown that solidification will reduce the arsenic contaminated soil's
teachability to below the TCLP limit for arsenic (Roy F. Weston December 1994a). After
solidification, the cemented soil would be disposed of in manageable pieces on-site within a
designated area in the CAMU. Forty thousand cubic yards of arsenic contaminated soil may require
solidification. Confirmatory sampling will be conducted to determine actual volumes. All site
arsenic containing waste will be consolidated into one small area which will be monitored.
3. C.°nSQl'(iflr'r>n and Soil Cover
The area of soil consolidation will be designated as a CAMU. to allow consolidation of soils
containing listed hazardous waste without triggering Land Disposal Restrictions (LDRs). A soil cap
will allow percolation of rain water, and will introduce moisture that is necessary for biological
activity. A RCRA cap would eliminate infiltration of moisture, and therefore restrict biological
activity while remediation is in progress.
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A soil cover will be placed over the CAMU. Areas on the site exceeding arsenic and PCP/Fuel Oil
yr RCLs (PRGs), in soil and sediment will be excavated to the appropriate ch. NR 720 Residual
Contaminant Level, and consolidated within the CAMU, prior to placement of the soil covers (Refer
to Figure 5). Co-mingling of arsenic and organics will be avoided to the extent possible. Portions
of the wood chip pile will also be excavated and consolidated within the CAMU. A fence will be
erected around the soil cover areas.
Removal of trees will be necessary in the area north and east of the lagoon prior to excavation.
Efforts will be made to save mature trees. The source areas will initially be covered with 6 inches
of clean soil from the uncontaminated areas west of the lagoon area. Following installation of the
erosion control measures and the lagoon and dam repair, an additional 6 inches of soil, with
sufficient organics to allow revegetation, would be placed on the soil cover area, and other areas
disturbed by the consolidation activities.
4. Biopad Removal
The biopad will be broken up into manageable sized blocks and used as backfill to support the
lagoon wall. This will also eliminate the potential of spreading arsenic contaminated concrete
chips into the wetland.
5. Erosion Control Measures
Severe surface water erosion is occurring at the PWP site. The apparent cause of most of this
^ erosion is rapid overland flow of water in the absence of vegetation and other natural flow barriers
at the site. Evidence of this erosion is seen by the gullies and channels that have formed in areas
whore drainage paths have coalesced.
An erosion control plan for the PWP site will be developed and implemented. This plan will involve
controlling surface-water runoff such that the volume and velocity of overland flow is reduced to a
level that will eliminate erosion of surface soils. This goal will be achieved by constructing drainage
ditches and water detention or infiltration basins at several locations on the site. The number and
type of erosion control structures will be determined in the design phase, and will take into account
the effect of interim surface control measures implemented by the U.S. EPA Emergency Response
Branch (ERB). Soil replacements, amendments and reinforcement may be necessary. The design
of drainage ditches will likely involve use of geotextiles and rip rap to prevent erosion of the sandy
material below and along the sides of the ditches during water flow. Check dams constructed of rip
rap will likely be used in steeper areas to slow the velocity of water flow. The gullies on the north
side of the PWP site may require some type of conveyance structures (e.g., corrugated metal
culverts) to convey water from the PWP site to the bottom of the sloped area.
Serious erosion has occurred on the downstream face of the lagoon dam embankment. This erosion
has resulted in the deposition of sand and wood debris that can be found 1000 feet downstream of
the dam, and the formation of gullies on both sides of the dam. The gullies coalesce into a single
gully 40 to 50 feet downstream of the crest of the dam. Cracks occur in several areas at the crest of
4 A the dam, suggesting that future failures are imminent.
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The lagoon dam repair and recontouring plan will involve stabilizing the existing gully area and
diverting some or ail of the surface water that currently reaches the lagoon to detention or infiltration
basins, or to other drainage areas. The goal of the lagoon dam repair effort will be to create a
uniform slope of about 15 to 20 percent, consistent with the slopes on either side of the existing
gully. The amount and type of material to achieve acceptable slope conditions downstream of the
lagoon will be determined during design.
6. Revegetation
A revegation plan will be developed and implemented in conjunction with the Erosion Control Plan.
Much of the PWP site is currently devoid of or sparsely covered with vegetation. Soils exposed at
the site are primarily sands and gravels with limited capacity to support plant growth. Following
consolidation of contamination from areas on the eastern side of the site, and excavation of areas on
the western side of the site for cover soil, reestablishing vegetation will be necessary over much of
the site.
The amount and type of revegetation will be consistent with the anticipated end use of the site and
surrounding land use. Several options are presented in the FS: one option that is proposed as part
of Alternative 2 is consistent with future commercial or industrial use, and involves importing
6 inches of organic rich soil to promote plant growth to allow rapid revegetation of the soil cover
area. In the excavated areas not provided with a soil cover, the grading and erosion control measures
•Aould allow vegetation to reestablish. This plant growth would likely consist of grasses, thistles,
and bushes within the central area of the PWP site, and pine and other trees around the perimeter of
the site.
~. LNAPL Removal
The objective of LNAPL system is to remove a source of PCP to the ground-water. Investigations
have identified a measurable LNAPL source just north of the Oil/Water Separator process area.
The designated LNAPL recovery system will consist of LNAPL recovery pumps, LNAPL sensing
probes, connecting pipes, controls, and a storage tank. The controls will be located within the
ground-water treatment building and will include on-off operation, storage tank high-level shutoff,
and remote sensing alarms. Other ground-water extraction wells will be designed and installed to
depress the water table in the LNAPL zone to promote LNAPL removal. All PCP contained in the
extracted ground-water will be removed or treated.
Initially the ground-water level in the LNAPL zone would be dropped slowly to study the effect on
the system, while removing the majority of the LNAPL. When the rate of LNAPL removal
decreases the water table would be dropped close to the elevation of the semi-confining till lens.
Operation of the LNAPL recovery system will be continuous. Routine maintenance of the system
will be required. LNAPL is a F032-listed hazardous waste, and the LNAPL will be sent off site for
incineration at a permitted RCRA Subtitle C Treatment. Storage, and Disposal (TSD) facility.
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8. Grossly Contaminated Ground-Water Treatment
w
The objective of this component is to collect and treat the most concentrated portions of the
. dissolved PCP/ Fuel Oil ground-water plume to a level which allows natural attenuation to achieve
ch. NR 140 standards within a reasonable period of time. The ground-water extraction treatment
system will consist of extraction wells, extraction pumps, connecting piping, oil-water separator,
controls, granular activated carbon (GAC) treatment train, metals treatment if necessary to meet
groundwater discharge standards, building, and infiltration basin(s).
Based on a previous pump test in the deeper confined aquifer, an extraction flow of 10 gpm yields
a radius of influence of approximately 200 feet (Conestoga-Rovers & Associates 1992). Therefore,
five extraction wells in the vicinity of the gully and lagoon source area will be required. More recent
well development data suggests that flows could be more on the order of 3 to 5 gpm in the
unconfined aquifer. It is assumed that the combined flow rate from each well is 10 gpm, resulting
in a total collection system flow rate of 50 gpm. The wells will be constructed of 6-inch poly vinyl
chloride ( PVC) pipe with 40 feet of screen below the water table and 10 feet above—a total of
approximately 140 feet well depth. The extraction pumps will be submerged and capable of
pumping a range from 2 to 10 gpm against 200 feet of total head.
Ground-water will be discharged to the oil/water separator, where the organic phase liquid will be
separated from the aqueous phase. The organic phase would be pumped to a storage tank. The
aqueous phase would be fed through the GAC vessels to remove residual dissolved organics, and
- 4 '.hen pumped out to the infiltration areas. Metals removal will be implemented if necessary to meet
^"^ discharge requirements. Controls will include on-off operation, high level alarms on the oil/water
separator, and shut down of the system should the infiltration areas become clogged. It is anticipated
that the system will be operated for 10 years to remove the majority (90 percent) of the PCP
contaminant mass (see Appendix F of the FS).
9. Monitored Natural Attenuation
This alternative includes natural attenuation for control and remediation of PCP/fuel oil to restore
the the bulk of the ground-water.
PCP concentrations in ground-water have been monitored at the site since 1988. Some of the wells
have 11 rounds of sampling data. PCP ground-water concentrations have shown consistent declines
at the majority of monitoring wells over time. There is a general decrease in the size of the PCP
plume, and the total contaminant mass of PCP in the saturated zone as measured in 1997 has
declined compared to the 1994 data. Contaminated ground-water is not discharging to the wetland,
or migrating below the wetland to surface water bodies.
The belief that PCP is biodegrading in ground-water is supported by the natural attenuation
parameter data collected at the site. This data consists of redox potential values, oxygen
concentrations, iron, nitrate, chloride and sulfate values that are indicative of reductive
dechlorination conditions. The ground-water plume is under anaerobic conditions in both the
fc 4 unconfined and semiconfined aquifer in the LNAPL area. The anaerobic plume is not expanding.
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The aerobic biodegradation at the aerobic/anaerobic interface has a faster decay rate than in the
anaerobic zone, apparently limiting plume spread. Estimated remediation time for the anaerobic
plume is decades if the LNAPL is not removed.
No estimates have been done on the site specific natural attenuation rates of benzene or naphthalene
in groundwater. These constituents are not wide spread in the ground-water, and it is believed that
these constituents naturally attenuate at a rate sufficient to limit their detection.
10. linritifi^pflfl] Controls
Institutional controls are necessary to ensure that the remedy is protective of public health, welfare
and the environment and will consist of land-use restrictions for the areas with a soil cover and
groundwater use restrictions for the entire site. It is anticipated that deed restrictions in the form of
an enforceable restrictive covenant will be used to: ( 1 ) identify the areas with the soil cover
(ueaunem area, gully and lagoon source areas) and the metals disposal area and specify that the area
is contaminated with PCP, Fuel Oil and/or arsenic, that excavation within the area must comply with
Occupational Safety and Health Administration (OSHA) requirements tor health and safety
protection, that any excavated soils be managed as hazardous waste in accordance with applicable
laws, that buildings are not permitted within the soil cover or metals disposal areas, and that
activities threatening the long-term integrity of the soil cover or the metals disposal area not
permitted; and (2) restrict installation of wells other than ground water monitoring wells within the
plume of groundwater contamination or within proximity to the plume that could affect plume
migration until the groundwater has been restored to compliance with ch. MR 140 standards.
Institutional controls other than or in addition to a restrictive covenant may be imposed if necessary.
1 1.
An Environmental Monitoring Plan will be developed and implemented to evaluate (1) the
effectiveness of naturally occurring processes in the subsurface soil and ground-water, (2)
compliance with State ARARs (ch. NR 140 and NR 720). and (3) evaluating the change in risks to
human health and the environment over time.
The objective of the soil environmental monitoring program is to assess the degree of natural bio-
intrinsic remediation of PCP'fuel oil constituents, and to determine whether the soil cover and
erosion control measures are preventing transport of arsenic and PCP/fuel oil. Environmental
monitoring of soil for Alternative 2 will include:
Lysimetcr sampling
Ground-water sampling of the contaminant plume
Routine inspection of cover and sampling if necessary
The existing lysimeter nests L Y02 and L Y03 will be sampled on an semi-annual basis for the first
five years to determine whether observable trends in pore water PCP/fuel oil constituent
concentrations are evident and to determine the amount of electron acceptors and donors and
degradation byproducts. Subsequent sampling, if necessary, will be based on these initial results.
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Analysis will include PCP, VOCs, semivols, TPH, chloride, nitrate, sulfate, dissolved iron,
hydrogen, oxidation/reduction potential, and pH.
Environmental monitoring of ground-water will assess the effectiveness of LNAPL removal and
ground-water treatment, and to follow the course of natural attenuation. The objective of the
monitoring program is to collect sufficient information to track the lateral and vertical extent of the
PCP/fuel oil contaminant plume, monitor benzene and naphthalene concentrations, and follow the
biodegradation of PCP/fuel oil constituents. The program will also allow assessment of continued
releases from the source area. If monitoring data indicate further spreading of the plume above
remedial goals, or that remediation goals will not be met within the 30-40 year estimated clean-up
time frame, treatment process modifications, such as the installation of additional extraction wells,
or other more aggressive remedy alternates mentioned in section IV of this ROD, will be considered.
The ground-water monitoring network for Alternative 2 will include the following wells:
Unconfmed monitoring wells 1 , 2, 6S, 9, 1 OS, 1 3, 1 6, and 1 9
Semiconfined monitoring wells 3, 4, 5, 7, 8, 10, 1 1, 12, 14, 15, 17
Three residential wells
The monitoring wells will be sampled semi-annually for 10 years and then at least annually until
remediation goals have been met. The environmental monitoring plan will be adjusted every five
years and as needed to assess performance of the remedial systems, progress toward meeting the
remediation objectives, residual risks to human health and the environment, project clean up times,
and other factors identified during the monitoring period. The samples will be analyzed for PCP,
petroleum VOCs including benzene and naphthalene and Target Analyte List (TAL) metals and for
the following natural attenuation indicator parameters-
Dissolved Oxygen (DO)
pH, temperature, and specific conductance
Oxidation/reduction potential
Alkalinity
Nitrate-and nitrite-nitrogen
Sulfate-and sul fide-sulfur
Total iron, ferrous iron, and ferric iron
Manganese
Carbon dioxide
Chloride
A smaller set of five monitoring wells (MW 3, 10, 10S, 13, 15) will be sampled and analyzed for the
above parameters on a quarterly basis for five years and then annually until the remedial objectives
have been accomplished. Further monitoring requirements will depend on the overall assessment
of the on-going analytical results.
A surface water sampling plan will be designed and implemented to assess remediation of the
wetland. Designated surface water sampling points will be sampled for PCP, petroleum VOCs,
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including benzene and napthaiene. PAH and ACZA metals. Descriptive water quality parameters
such as pH, hardness, ammonia nitrogen. COD will be collected and compared to background.
A monitoring plan will be designed to assess performance of the arsenic/metals disposal area.
This alternative includes development of a ground-water flow and solute transport model to allow
prediction of contaminant transport, degradation rates and remedial time frames. The model will be
updated annually based on actual monitoring results.
12. Point-nf-Use Carbon'Treatment or Well Replacement
Point-of-use carbon treatment or well replacement for the residential wells bordering the site may
be necessary if PCP exceeds Ch. NR 140 ground-water quality standards at these wells. The choice
of remedy will be dependent on the preference of the well owner, aesthetic water quality, and
expected well life. The Breihorst, Crosby and Skold Residential wells on Daniels 70 will be
monitored semi-annually at a minimum, and more frequently if there are indications of plume
movement toward these wells during remediation.A typical treatment system may consist of two
canisters installed in series. The upstream canister will be replaced on a schedule that will insure
safe drinking water standards are being met. This schedule will be established using conservative
carbon adsorption chemical-specific modeling. The treatment system installation will meet the
substantive requirements of Wisconsin plumbing codes for point of use treatment systems.
!?•: Five-Year Site Reviews
Five-year site reviews, consisting of cover inspections, evaluation of all prior surface soil, lysimeter
and ground-water sampling analysis, will be conducted to assess the effectiveness of erosion control
measures, impacts of contaminants to ground-water and performance of the remedial measures. The
evaluation will be used to update the estimated restoration time frame, examine the feasibility of
implementing any improvements or contingencies and to evaluate potential risks to human health
and the environment The five-year review requirement will be terminated when the ground-water
quality has been restored to compliance with ch. NR 140 and soils have been remediated in
compliance with ch. NR 720.
Residual risks will remain at the PWP Site from contaminants in subsurface soil and ground-water
within the anaerobic plume. Institutional Controls will restrict the potential future access to and use
of ground-water and soil under the cover, thereby eliminating the contact and ingestion pathways
as a source of residual risk.
Estimated Time to Design and Construct = 2 years
Estimated Remedial Time Frame for Soils near Water Table = Decades
Estimated Remedial Time Frame to meet PALs in LNAPL area = Decades
Total Capital Costs = S2.3 million
Total Operation and Maintenance Costs (net present worth) = $2.9 million
Total Costs (net present worth) = $5.2 million
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C. ALTERNATIVE 3 - SOIL CONSOLIDATION AND COVER. B1OVENT1NG.
GROUND-WATER AND LNAPL COLLECTION AND TREATMENT. AND
MONITORED NATURAL ATTENUATION OF GROUND-WATER
This alternative consists of the same 13 components as Alternative 2 with the addition of bioventing
to enhance aerobic degradation processes, and shortening the time to reduce PCP soil levels to
cleanup values. In this alternative, the LNAPL residual zone will be dewatered, improving the
conditions for bioventing degradation of PCP. The biovent zone will be extended about 10 feet
deeper into the currently saturated zone by lowering the LNAPL surface during the LNAPL removal
process.
This alternative includes the following, in addition to those described in Alternative 2:
Bioventing Construction
Bioventing Operation
(additional) Environmental Monitoring
The objective of bioventing is to enhance aerobic degradation of PCP-contaminated soil by injecting
air into the unsaturated zone above the ground-water table. Bioventing will be conducted in the
gully and lagoon source area after the soil solidification, soil consolidation, bippad relocation and
cover is completed.
1. Construction
i he fro venting system will consist of air injection wells, inner-connecting piping,, blower, controls,
treatment building, and piezometers. Approximately 10 injection wells will be installed in the
lagoon and gully area. The air injection wells will be constructed of 4-inch diameter PVC pipe with
125 feet of screen terminating below the ground-water table. The wells will be connected to piping
that will be located below the frost line. The piping will provide individual flow control to each
well.
The blower, located in the treatment building, will be capable of supplying each well with an air flow
of approximately 500 standard cubic feet per minute (scfm) at 10 pounds per square inch gauge
pressure. The controls will be programmed for automatic operation, emergency shutoff, on-off timer
control, and remote sensing.
Piezometers at varying depths will be installed in discrete locations. The purpose of the piezometers
is to allow for the monitoring of soil gas composition to assess effectiveness in delivering air to the
affected subsurface regions.
2. Operation
Length of operation of the bioventing system is based on the estimated time to reach ch. NR 720
RCL for PCP. PCP aerobic degradation rates at PWP could range from 0.1 to 0.75 ppm/day (Section
2 of the FS). Average PCP concentrations in the unsaturated soil and LNAPL residual zone are 150
mg/kg and 1,500 mg/kg respectively (Section 2 of the FS). Based on the higher PCP concentration
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and an average degradation rate of 0.5 mg/kg per day. the estimated time to reach the preliminary
PRG for protection of ground-water of 4.6 mglcg is approximately 10 years.
3. ^liYJrftnillCllt?^ Monitoring
The objective of the Alternative 3 environmental monitoring program is to assess the degree and
effectiveness of PCP removal and whether the soil cover and erosion control measures are preventing
transport of arsenic and PCP 'fuel oil. Environmental monitoring for Alternative 3 will include:
Soil gas analyses and soil sampling in the bioventing treatment area
Routine inspection of cover and sampling if necessary
Performance monitoring of the arsenic/metals disposal area
Lysimeter and ground-water sampling will be performed as in Alternative 2.
Soil gas analyses will be conducted semi-annually at a minimum. Analyses for oxygen, carbon
dioxide, methane, temperature, and moisture will be measured in the piezometers and the monitoring
wells identified for ground-water sampling. If levels are out of acceptable ranges, process
modifications may be proposed. For example, insufficient soil moisture may facilitate the
installation of air sparging wells in the bioventing treatment areas to augment the moisture content,
as well as provide additional oxygen to the more stagnant air near the water table.
Soil samples for PCP, VOC including Napthalene, and PAH. and the degradation indicators of
chloride and pH, will be collected at 3, 5, 7 and 10 years. Samples will be collected at discrete
locations and at various depths. More aggressive remedial action will be considered in accordance
with the contingency plan if site monitoring data demonstrates that remedial objectives set forth in
Section VIII of this ROD will not be met within 30-40 years.
Estimated Time to Design and Construct = 2 years
Estimated Remedial Time Frame for soils above the water table =10 years
Estimated Remedial Time Frame to meet PALs in ground-water = 30-40 years
Total Capital Costs = $3.8 million
Total Operation and Maintenance Costs (net present worth)= $4.4 million
Total Costs (net present worth) = S8.2 million
D. ALTERNATIVE 4 - SOIL CONSOLIDATION AND COVER. BIOVENTING.
GROUND-WATER AND LNAPL COLLECTION AND TREATMENT
THROUGHOUT PLUME
Alternative 4 is the same as Alternative 3, with the exception that the entire plume of PCP-
contafninated ground-water (> I ug/L PCP) would be collected and treated, instead of allowing the
plume to naturally attenuate. Fourteen ground-water extraction wells would be required instead of
five wells: thirteen in the vicinity of the gully and lagoon source area, and one in the vicinity of MW-
8. The system is assumed to be operated for the entire 30 year present worth cost estimating period.
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Estimated Time to Design and Construct = 2 years
Estimated Remedial Time Frame for soils near water table = 10 years
Estimated remedial time frame to meet PALs in LNAPL area = Decades
Total Capital Costs = $4.6 million
Total Operation and Maintenance Costs (net present worth) = $4.6 million
Total Costs (net present worth) = $9.2 million
E. ALTERNATIVE 5 - SOIL CONSOLIDATION AND COVER. BIOVENT1NG. AND
STEAM INJECTION WITH SOIL VAPOR EXTRACTION
The objective of Alternative 5 is to remove the bulk of the PCP/LNAPL residual zone area using
steam injection in conjunction with Soil Vapor Extraction (SVE). The remainder of the PCP plume
will be allowed to naturally attenuate. It is estimated approximately 90 percent of the PCP in the
LNAPL residual zone will be recovered with steam injection/SVE. The remaining components of
Alternative 5 are identical to Alternative 3.
1. Steam Injection in Conjunction with SVE
The objective of this component is to inject steam to recover the PCP/LNAPL mixture through
subsurface volatilization. Steam would be injected into wells that are screened in the zone of the
PCP/LNAPL residual. The steam moves in a thermal front towards the SVE wells, first physically
displacing the LNAPL towards the SVE wells, and then volatilizing the PCP/LNAPL (USEPA
1998a). The physically displacing and steam-volatilized PCP/LNAPL mixture is withdrawn from
ihese SVE wells and recovered at the surface. Ground-water is also pumped out of these wells to
provide for capture of the PCP/LNAPL mixture that may have re-solubilized. Soil treatment will
be conducted sequentially in 100 by 100-foot cells because of the high costs associated with the
process equipment and fuel.
Steam injection would consist of injection and extraction wells, connecting piping, boiler, blower,
catalytic oxidizer, and ground-water extraction pumps. Approximately 120 total wells would be
installed in the 4-acre LNAPL residual zone aitea, half of which will be used to inject steam and the
other half to extract the volatilized PCP/LNApL mixture. The injection and extraction wells would
be 4-inch diameter, and constructed with approximately 10 feet of stainless steel screen and 100 feet
of cast iron risers. The wells would be inner-Connected to piping to and from the treatment system
process equipment.
The boiler would be capable of producing 10,000 Ib/hr of steam to the injection points. Water would
be pumped from a separate ground-water supply well, which would be installed in an
uncontaminated area in the western portion i)f the site. Boiler make-up water would need to be
treated prior to use. Liquid propane would be used as fuel.
i
The condensed PCP/LNAPL would be seperated from the water phase and sent off site to a RCRA
Subtitle C TSD facility. The water phase would be treated and recycled to the boiler. Air emissions
from the condenser would be catalytically oxidized.
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Ground-water recovery will also be necessary to control and capture PCP/LNAPL that may
mobilize. Approximately eight wells would be used for ground-water recovery. The ground-
water would be treated via carbon adsorption and either re-used as boiler make-up or discharged
to infiltration trenches on-site. For costing purposes, it is assumed that treatment for both the
condensate and the ground-water would total about 60 gpm.
Length of operation of the steam injection system is based on reducing the PCP to the extent
practical within reasonable costs. Based on vendor-supplied information, a treatment tune of three
months in each cell should be sufficient to reduce PCP'LNAPL about 90 percent, the practical
limit. This corresponds to a total treatment time of about seven and one half years based on the
30 cells. Additional bioventing of the residual PCP may be required after the free liquid has been
removed. This possibility, and subsequent costs, have not been included in this remedy.
Estimated Time to Design and Construct = 2.5 years
Estimated Remedial Time Frame for soils near water table = 10 years
Estimated Remedial Time Frame to remove recoverable PCP = 7.5
Total Capital Costs = $7.5 million
Total Operation and Maintenance Costs (net present worth) = $10.1 million
Total Costs (net present worth) = $17.6 million
X. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES
The relative performance of each remedial alternative was evaluated in the FS using the nine
criteria set forth in the NCP at 40 CFR Section 300.430. A remedial action providing the "best
balance" of trade-offs with respect to the nine criteria is determined from this evaluation.
A. THRESHOLD CRITERIA
1. Overall protection of IMHMB iKahh and the enTiroamcal addresses whether or
not a remedy provides adequate protection and describes how risks posed through each pathway
are eliminated, reduced, or controlled through treatment, engineering controls, or institutional
controls.
• wMi ARARs describes how die alternative complies with chemical-,
Hxahon-. and action-specific ARARs. or other criteria, advisories, and guidance.
B. PRIMARY RAl.ANriNC CRITERIA
The following five criteria are used to compare and evaluate the elements of one alternative to
another dm meet the threshold criteria.
3. l,oa)gimii effecthrcMSs and permanence evaluates die effectiveness of
alternatives in protecting human health and the environment after response
objectives have been met, in terms of the magnitude of residual 'risk and the
adequacy and reliability of controls.
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4. Reduction in toxicity, mobility, or volume through treatment evaluates the
treatment technologies by the degree of expected reduction in toxicity, mobility,
or volume of hazardous material. This criterion also evaluates the irreversibility
of the treatment process and the type and quantity of residuals remaining after
treatment.
5. Short-term effectiveness addresses the period of time needed to achieve protection
and any adverse impacts on human health and the environment that may be posed
during the construction and implementation period, until the remedial action
objectives are achieved.
6. Implementability assesses the ability to construct and operate the technology; the
reliability of the technology; the ease of undertaking additional remedial actions;
and the ability to monitor the effectiveness of the remedy. Administrative
feasibility is addressed in terms of the ability to obtain approvals from other
agencies. This criterion also evaluates the availability of required resources, such
as equipment, facilities, specialists, and capacity.
7. Costevaluates the capital and operation and maintenance costs of each alternative,
and provides an estimate of the total present worth cost of each alternative.
C. MODIFYING CRITERIA
The modifying criteria are used in the final evaluation of remedial alternatives after public
comment on the Rl/FS and Proposed Plan has been received.
3. State acceptance addresses whether, based on its review of the RI/FS and
Proposed Plan, the state concurs with, opposes, or has no comment on the
proposed remedial alternative. The State of Wisconsin has provided comments on
the RI/FS and the Proposed Plan, and has documented its concurrence with the
remedial action in its letter of concurrence, and is presented in Appendix A.
9. Community acceptance addresses whether the public concurs with the Proposed
Plan. Community acceptance of the Proposed Plan is typically evaluated based on
comments received at the Public Meeting and during the public comment period.
This is documented in the Responsiveness Summary presented in Appendix C.
The section below presents the nine criteria and a brief summary of each alternative and its
strengths and weaknesses according to the comparative analyses.
Overall Protection of Human Health and the Environment
Site conditions currently pose risks to human health and the environment via soil, sediment, and
surface water exposure pathways. The potential also exists for future human health risks
associated with exposure to ground-water. All the alternatives except Alternative 1 prevent
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erosion and direct contact with soil and sediments, and remove the contaminated material from the
wetland. Alternatives 3 through 5 actively treat the subsurface soils and smear zone, reducing
residual risks quicker, and reduce the contaminant mass available to leach into the ground-water.
Alternative 2 relies on natural processes to degrade die subsurface soil contaminants. Alternatives
2 through 4 pump-and-treat ground-water, with Alternatives 2. 3 and 5 relying on monitored
natural attenuation to treat die low level PCP content of die plume. Alternative 4 treats the entire
plume. Alternative 5 uses a different technology approach to remediate the LNAPL area.
Alternatives 3. 4 and 5 will comply with chemical-specific ARARs (ch. NR 140 and ch. NR 720)
within a reasonable period of time (i.e.. within 30 to 40 years). For Alternatives 2 through 5,
Wisconsin NR 680 exemptions and/or Wisconsin NR 600 waivers may be necessary to meet
ARARs associated with classification, treatment, disposal, and/or placement of listed hazardous
wastes, or a CAMU may be established and accepted under chapter NR 636 Wisconsin
Administrative Code.
Tbe btoventing alternatives (Alternatives 3 through 5) are die best alternatives in long-term
effectiveness and permanence because diey reduce die PCP content and theifore reduce die
leaching of PCP from soils near die water table into die ground-water.
The long-term effectiveness and perma
of die steam injection in conjunction with the SVE
alternative (Alternative 5) is better dian the other alternatives, because Alternative 5 actively
removes the PCP mass causing the ground-water contamination. The ground-water collection and
treatment alternatives (3 and 4) are similar in their long-term effectiveness and permanence. Only
minimal additional PCP is removed in Alternative 4 compared to alternative 3.
Metals contaminated soil will be placed in a CAMU designed to prevent the transformation of metals
:o a more soluble state.
The bioventing alternatives (Alternatives 3 and 4) offer die best Tbxicity, Mobility, or Volume
jTMV) reduction for the soils. About 80 to 90 percent of the estimated 120,000 IDS of PCP is
expected to be reduced in about 10 years. This treatment is irreversible. All alternatives (except no-
action) include solidification of arsenic-contaminated soil that tests above NR 720 RCL for ground-
water protection. The biopad containing solidified arsenic-contaminated soil will be broken up into
pieces and placed under the soil cover cap. This will eliminate the threat of surface transport of
arsenic as the pad weathers and pieces flake off over time.
For Alternative 2, active soil treatment is not used. Reduction in TMV through natural
biodegradation would occur, but the degradation rate is slow and could take many decades.
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Steam injection (Alternative 5) is comparable in TMV reduction for ground-water to Alternatives
3 and 4. The ground-water collection and treatment for the entire plume (Alternative 4) affects a
larger zone, but removes only marginally more PCP than Alternative 3. Alternative 5 is predicted
to remove up to 90 percent of the 500,000 gallons of LNAPL and 26,000 Ib of PCP in the saturated
zone. The predicted TMV reduction for Alternatives 3,4 and 5 is the same, but Alternatives 3 and
4 may take longer.
Short Term Effectiveness
The no-action alternative has no impact because the alternative involves no remedial construction.
All the other alternatives have minimal impacts with respect to the protection of workers during
remedial construction, protection of community during remedial action, and environmental impacts
of remedial action. The primary environmental impact is during wetland consolidation. This would
be minimized by following guidance set forth by the Army Corp of Engineers.
Odors and fugitive dust may result because of the excavation and handling of the contaminated
soil/wood debris during excavation and consolidation. Risk to construction workers will be
minimized through air monitoring and use of emission control techniques as necessary (e.g. dust
suppressants). Short-term nuisance noise impacts and safety-related risks to the community caused
by truck traffic will be minimal.
Implementabiiity ••
Technical or administrative implementability problems are not expected to be significant for any of
ihe alternatives. Exemptions and/or waivers with respect to classification, treatment, disposal, and/or
placement of listed hazardous wastes, or State acceptance of a CAMU, will be necessary.
Cost
The capital, operation and maintenance costs, and net present worth costs are presented for each
alternative in the Description of Alternatives (Section IX). The cost estimates have been developed
strictly for comparing the five alternatives. The cost estimates are order-of-magnitude estimates
having an intended accuracy range of+50 to -30 percent; the specific details of remedial actions and
cost estimates would be refined during final design. The operation and maintenance (O&M) costs
are based on a 30 year duration. Net present worth for O&M costs is calculated using a seven
percent discount rate.
The no-further-action alternative has no cost, while the steam stripping with SVE and bioventing
alternative has the highest cost. Of the alternatives that actively remediate the LNAPL smear zone,
Alternative 3 is the least costly.
V.'
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The State of Wisconsin has provided comments on the RI. FS and the Proposed Plan and has
documented its concurrence with the remedial action as stated in Section IX. A copy of the State's
letter of concurrence is included as Appendix A.
Community acceptance of the Proposed Plan was evaluated based on comments received at the
Public Meeting and during the public comment period. There were no comments concerning the
Proposed Plan. There was no opposition raised to the Selected Remedy. This is documented in the
Responsiveness Summary presented in Appendix C.
XI. THE SELECTED REMEDY
U.S. EPA has selected Alternative 3 as the remedy for the PWP Superfund Site. Alternative 3
addresses soil, sediment ground-water and source areas associated with the site. Alternative 3
includes:
cover, biovi
Irromt
Estimated Time to Design and Construct = 2 years
Estimated Remedial Time Frame for soils above the water table = 10 years
Estimated Remedial Time Frame to meet PALs in ground-water = 30 to 40 years
Total Capital Costs = S3.8 million
Total Operation and Maintenance Costs (net present worth)= $4.4 million
Total Costs (net present worth) = $8.2 million
(Appendix G of the FS presents a detailed break down of costs)
U.S. EPA and WDNR have determined that the selected remedy provides the best balance amongst
the nine criteria. The selected remedy meets the requirements of CERCLA and has received no
public opposition.
A.
CLEANUP LEVELS
WDNR PALs were selected as cleanup goals (or the PWP Site ground-water to the extent practicable
as the most stringent federal or state promulgated drinking water standards. The results of the
baseline risk assessment indicate that potential future exposure to ground-water results in an
unacceptable "exposure level" to human health. Compounds are present at concentrations associated
with a noncarcinogenic risk greater than an HI equal to 1 and/or carcinogenic risk greater than 10~*.
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. j Cleanup levels for soils are based on varying PRGs dependent on the specific COPC. The PRGs
*Htr considered are shown in Table 1 and include health-based risk levels, soil concentrations protective
of ground-water, background levels, and quantitative ecological risk-based levels.
1. Ground-Water
Four ground-water COPCs (PCP, benzene, naphthalene, and arsenic) are present at concentrations
associated with elevated risk estimates, and three COPCs (iron, manganese, and chloride) are present
at levels above taste or odor aesthetics levels. Exposure to PCP accounts for over 99 percent of the
baseline carcinogenic risk and baseline noncarcinogenic risks estimated in the FHHRA. Remedial
actions taken to reduce exposure to or concentration of the PCP/oil layer will result in a concurrent
reduction of exposure to other compounds present in the ground-water. Benzene and naphthalene
are associated with the fuel oil carrier, and the elevated arsenic, iron, and manganese levels are native
minerals solubilized due to reducing conditions caused by the presence of the LNAPL source. Table
2 lists the federal MCL and state ground-water quality standards for these COPCs. At the
completion of the remedial action the ground-water will comply with Wisconsin PALs, and the
ground-water will have been restored to its highest beneficial use.
2. Sfiils
Only arsenic and PCP are present at concentrations associated with elevated human risk estimates.
Copper and zinc are present at concentrations associated with elevated ecological risk. Table 1
* A presents the cleanup goals for these constituents, as well as other compounds that have been detected
^* at the site, but do not exceed soil health-based criteria. The shallow soil clean up goals are based
on a 1x10'6 cancer risk level and/or a HI of 1. The clean up goals for copper and zinc were
established to be in the midrange of the ecological PRGs. Soil COPCs also have a subsurface soil
clean up goal designed to be protective of ground-water. At the completion of the remedial action
the majority of the site will be available for productive use. The area inside fenced area will be
restored to beneficial use when the soils no longer cause ground-water contamination exceeding ch.
NR 140 PALs for PCP. The small area inside the fenced area containing immobilized arsenic wastes
will have very limited long range utility (e.g. a parking lot).
3. Sediments
Ecologically-driven numerical clean up goals for sediments need to be balanced with consideration
of the habitat destruction that accompanies physical removal of the contaminated sediments. The
selected remedy balances these conflicting threats to the wetland environment by blocking the source
of contamination (the collapsing lagoon wall), and removing sediments from the toe of the western
lobe to approximately 200 feet from the contaminant entrance point. Visible signs of fuel oil will
also be removed. Remaining PCP contamination in surface water will degrade naturally by
photolysis. At the completion of the wetland remedial action, monitoring will confirm that the area
will meet the ecological and human health based risk goals.
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B. DESCRIPTION OF REMEDIAL COMPONENTS
The selected remedial alternative for the site actively treats the principal threat in soil, sediment, and
ground-water and acknowledges the natural biodegradation processes occurring within the aerobic
area of the ground-water plume. Environmental monitoring will be conducted to evaluate the
continued effectiveness of natural attenuation processes. Institutional controls will be implemented
to protect public health by restricting future use of contaminated soils and ground-water during the
time that is needed to reach clean up goals. The components of this alternative were described in
Section IX-Description of Alternatives. The following discussion provides additional detail for
some of the key components of the alternative
!. virnmgntal
The details of establishing pi ogress toward aquifer and soil restoration will be developed in a Long
Term Monitoring Plan as pan of the Remedial Design. Individual contaminants will be evaluated
at each monitoring event to establish the trend (improving or deteriorating) of the ground-water and
soil restoration. A contingency plan will be provided in the Long-Term Monitoring Plan and will
be implemented to protect human health and the environment if environmental monitoring and
modeling predicts or detects exceedences of health/ecological based values. For trends that predict
rcceedences, this plan will require an evaluation of the impacts of the exceedence, potentially
leading to increased monitoring, or the implementation of one of remedial options identified in the
7S, or other suitable remedies, to prevent further release of contaminants. These measures may
include: installing point-of-use carbon treatment or well replacement on residential wells; ground-
water pump-and-treat throughout the whole plume: steam heating and/or thermal removal of the
LNAPl. Tone: enhanced bioremediation; in-situ oxidation, a combination of these procedures; or
other technology as approved by the U.S. EPA. in consultation with WDNR.
The remedial action will be continued until the ground-water has been restored to PALs. or an
appropriate exemption or waiver is issued.
2. inajritiitiflnjl {^pntrols
Institutional controls in the form of ground-water use restrictions and land use restrictions will be
implemented to prohibit site ground-water use and restrict activities in the fenced soil cover area and
metals disposal area. Institutional controls will be drafted, implemented, and enforced in
cooperation with the property owner and the federal, state, and local governments.
3.
The selected remedial alternative includes active remediation of the LNAPL source, treatment of
grossly contaminated groundwater, bioventing of the soils above the LNAPL and natural attenuation
for treatment of POP in and at the perimeter of the ground-water plume. Alternate remedial
technology will be considered if monitoring data indicate that the remedial objectives will not be
meet within 30-40 years. Extensive site characterization data indicate that natural attenuation is
effectively containing the spread of contamination by reducing contaminant concentrations. Natural
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1^ j attenuation is an appropriate remediation method only where it is fully protective of human health
^* and the environment, and where it can be demonstrated capable of achieving site-specific
remediation objectives (e.g., PALs) within a reasonable time frame. The NCP states that
remediation time frame for restoring ground-water to its beneficial use should be developed based
on specific site conditions. Under these natural attenuation processes, the time to achieve PALs is
dramatically shortened once the LNAPL and highly contaminated ground-water has been removed.
With institutional controls to prohibit use of the ground-water on the site, the time frame projections
shown are reasonable if bioventing is effective in reducing contaminant mass in the soils above the
water table, and LNAPL removal reduces the source of ground-water contamination.
4. Five-year Site Reviews
Under CERCLA Section 121(c), a remedial action that results in hazardous wastes, pollutants, or
contaminants remaining on site must be reviewed every five years. Data collected during the
monitoring program will be used to assess potential impacts of contaminants, and evaluate whether
human health and the environment continue to be protected. To the extent that U.S. EPA's five-year
review indicates that it is not technically or economically feasible to achieve PALs, s. NR 140.28,
Wisconsin Administrative Code, provides for substantive standards for granting exemptions from
the requirements to achieve PALs. Such exemption levels may be no higher than the ES. If U.S.
EPA in consultation with WDNR determines that it is technically impracticable to achieve PALs or
other standards within a reasonable period of time, and for some reason the exemption allowed with
s. NR 540.28 is not appropriate, a Technical Impracticable applicable or relevant and appropriate
^g/ requirements (ARAR) waiver under CERCLA may be granted for the site.
5. Soil Cover
The soil cover above the LNAPL source area, and lagoon erosion control features, will be visually
inspected annually and repaired as necessary (e.g., resurfaced, patched). This cover will eliminate
the potential of recontaminating the wetland after the sediment and washout soil removal, and reduce
potential access/direct contact to contaminated soils by human and ecological receptors.
6. Operation and Maintenance Plan
An operation and maintenance plan will be designed and implemented to address all post
construction related site activities, including the criteria identified in NR 636.40(5). This includes
activities that pertain to sampling and analysis, inspection schedules, contingency plans and a
closure plan when remedial goals have been met.
C. LONG-TERM MONITORING PLAN
The Long-Term Monitoring Plan will present specific details of the long-term sampling and analysis
requirements for compliance monitoring as required by the selected remedy. This plan will present
the location of each sampling point, sampling protocol, analytical method, analytical level, data
evaluation level employed for each sampling location during the long-term monitoring phase of the
» j remedial action. The Long-Term Monitoring Plan will also present the method used to determine
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exceedence or projected exceedence. when and what action(s) (contingencies) will be taken to
protect human health and the environment if exceedences are reported above specified action levels.
XII. STATUTORY DETERMINATIONS
The selected final remedy for the PWP Site is consistent with CERCLA and is in compliance with
the NCP to the extent practicable. The selected remedy is protective of human health and the
environment, attains ARARs, and is cost effective. The selected remedy also satisfies the statutory
preference for treatment that permanently and significantly reduces the toxicity. mobility, or volume
of hazardous substances as a principal element. The following describes how the selected remedy
meets these requirements.
A. THE SELECTED REMEDY IS PROTECTIVE OF HUMAN HEALTH AND THE
ENVIRONMENT
The selected remedy will provide adequate protection of human health and the environment through
consolidation and soil cover of direct contact soils, institutional controls to prevent exposures to
ground-water and through the treatment technologies to be employed. The potential risks associated
with access to/use of the site will decrease over time because natural attenuation, LNAPL removal,
~nd bioventing will reduce the concentration of contaminants to the ground-water quality standards
'.isted in Table 2. Environmental monitoring will be used to determine if the selected final remedy
will achieve the remediation objectives within 30-40 years. I f monitoring data demonstrates that the
remediation objectives will not be met within this restoration time frame, more aggressive remedial
action will be considered.
B. THE SELECTED REMEDY ATTAINS ARARs
The selected remedy will comply with identified federal and state ARARs. Potential chemical-,
location-, and action-specific ARARs were identified, defined, and summarized in Appendix A of
the FS report. Table 8 presents an overview of the ARARs for the selected remedy. Activities
associated with the selected remedy will be conducted consistent with OSHA and other applicable
regulations. No unacceptable short term risk will occur as a result of remedy implementation.
A brief narrative of significant ARARs, and other criteria, follows.
1. fimund-Water Regulations
Chemical-specific ARARs for site ground-water include regulations and criteria promulgated under
the Safe Drinking Water Act (SDWA), Clean Water Act, and Stale of Wisconsin statutes. In
addition, certain other numerical goals will be attained. The federal National Drinking Water
Regulations consist of contaminant-specific standards known as MCLs and Maximum Contaminant
Level Goals (MCLGs). MCLs are enforceable standards that are the maximum permissible level
for specific contaminants in public water supplies. MCLGs are non-enforceable health-based goals
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. , that establish levels at which no known or anticipated adverse health effects occur. The NCP, at 40
'W C.F.R. section 300.430(e)(2)(iXB) and (C), requires that MCLGs above zero, and MCLs where the
MCLG for a contaminant has been set at zero, be attained for ground-water sources that are current
or potential sources of drinking water.
Under the Wisconsin Ground-Water Quality Rules, found in ch. NR 140, Wisconsin Administrative
Code, the state has adopted PALs that are more stringent than federal MCLs, that must be met at
every point where groundwater is monitored on the site. Groundwater cleanup levels for the site
were set at PALs. The selected remedy will be complete when PALs have been achieved in the
ground-water plume. Use of the groundwater at the PWP Site will be restricted by implementing
a groundwater use restriction until PALs are reached.
2. Effluent Limits
The substantive elements of the Wisconsin Pollutant Discharge Elimination System (WPDES)
permit process will be used to establish the effluent limits for discharge of treated ground-water to
surface water or ground-water (NR 102, NR 103, NR 104, NR 105, NR 106, NR 200, NR 207, and
NR 220 and ch. 283, Wis. Stats.). Discharge limits for treated ground-water to surface water will
need to meet Wisconsin surface water quality standards. Infiltration or reinjection of effluent
(treated ground -wafer) to ground-water must meet the substantive requirements: of WPDES an NR
140.28(5).
* j ::. Soil Residual Concentrations
The chemical-specific ARARs for residual soils are the Wisconsin soil cleanup standards in NR
720. Chapter NR 720 provides generic RCLs and the procedures and risk assumptions for
determining site specific soil cleanup standards that are protective of public health, safety,, welfare
and the environment. The generic RCL or site-specific RCL must be protective of the NR 140
ground-water standards for all contaminants of concern. The risk-based RCLs developed under NR
720 will be the basis for acceptance of any variances or exemptions under other regulatory
authorities. The soil cleanup standards developed pursuant to NR 720 procedures are considered
substantive requirements that are consistent with the NCP.
4. Classification of Wastes
The most significant ARARs that affect the alternatives involving excavation and treatment of soil
are the requirements developed pursuant to Subtitle C of the Resource Conservation and Recovery
Act (RCRA), as amended by the Hazardous and Solid Waste Amendments of 1984. RCRA Subtitle
C requirements are ARARs if the wastes to be managed are listed or characteristic wastes under
RCRA and the wastes were treated, stored, or disposed after the effective date of the RCRA
requirements under consideration or the activity at the CERCLA site constitutes treatment, storage,
or disposal as defined by RCRA. The waste at this site is RCRA hazardous waste F032 and F035,
wastewaters, process residuals, preservative drippage, and spent formulations from wood preserving
processes generated at plants that currently use or have previously used chlorophenolic formulations,
». j or generated at plants that use inorganic preservatives containing arsenic or chromium. The listings
45
-------
for F032 and F03S wastes were promulgated on Dec 6, 1990 PWP did not cease disposing of this
waste until 1992. after the effective date of the listing, and therefore, RCRA ARARs are applicable.
The RCRA requirements, as established in the WDNR NR 600 rule series, are applicable if the
activity being considered as pan of the remedial alternative constitutes treatment, storage, or disposal
as defined by RCRA. The RCRA requirements are considered an ARAR, and the excavation and
disposal activities will require compliance with RCRA waste management standards including
accumulation, storage, transportation, and land disposal restrictions, consistent with the preamble
to the NCR (55 Fed. Reg. 8758-8760. March 8. 1990)
Alternatives for soil reconsolidation or redisposal units on-site must meet the ch. NR 600 land
disposal minimum technology requirements (MTRs) for hazardous waste landfills, including a liner
and a leachate collection system unless:
Appropriate LDRs or NR 720 RCLs. whichever is more stringent are met prior
to redisposal
An exemption is granted under NR 680.04
A Corrective Action Management Unit (CAMU) is established and justified under
NR636
A CERCLA waiver is issued by U.S. EPA
CAML! The CAMU rule within RCRA (40 CFR 264 Subpart S [264.552]) allows movement of
contaminated material within an area of contamination without triggering the requirements for
"Senerated" hazardous waste. In essence, it allows consolidation of contaminated soils and
sediments containing listed or characteristic waste, without triggering the LDR requirements. This
concept is needed tor alternatives involving consolidation followed by containment under a cover
or otherwise the alternative would not comply with RCRA ARARs.
Wisconsin has adopted the CAMU rule in NR 636. If a CAMU is established under NR 636, the
LDRs do not apply. Remedial Design details will address criteria in NR 636.40(3)(b) to insure that
the waste management activities associated with the CAMU will not create unacceptable risk to
humans and environment from exposure to the hazardous waste or hazardous constituents.
The arsenic containing soils will be consolidated and separated from organic contaminants to the
extent practicable in the CAMU. The total area will be biovented to promote bioremediation of the
PCP/fuel oil.
RCRA requires that the arsenic-and PCP-contammated soils be capped with a cover which is in
compliance with RCRA design standards. However, a RCRA cover will decrease the efficacy of the
btoventing of the PCP-contaminated soils by severely reducing the soil moisture that is crucial for
biological activity. Although the bioventing will not address co-mingled arsenic, the RCRA cover,
while meeting ARARs, would not significant!) reduce the migration potential of the arsenic or
provide more protection. Since a RCRA cover would render the bioventing of the PCP less
effective, without reducing the mobility of the arsenic, the proposed soil cover will provide adequate
protection at this site.
46
-------
Region 5 Office of RCRA has reviewed the selected remedy and agrees with a CAMU.
The Arsenic/metals contaminated soil will be tested with a conservative leachability test such as
TCLP for its potential to become mobile. Soils failing to meet an NR 720 RCL protective of
groundwater in TCLP leachate will be solidified prior to placement in the CAMU. In addition, the
CAMU will be designed to eliminate conditions which could result in transformation of metals to
the mobile form.
The requirements under NR 636.40(5) that must be addressed for the PWP site will be part of the
Operation and Maintenance Plan (O&M). This includes activities that pertain to sampling and
analysis, inspection schedules and contingency plans. The need for a RCRA Cap will be reviewed
at closure. If necessary, a RCRA cap will be constructed on the CAMU areas consistent with the site
closure plan.
5. Wetlands
The most important location-specific ARARs for the PWP site are the requirements for protection
of wetlands (Executive Order 11990 and ch. NR 103, Wisconsin Administrative Code). These
ARARs require that actions at the site be conducted in ways that minimize the destruction, loss, or
degradation of wetlands.
6. Air Regulations
. The need for control or treatment of air emissions will be evaluated during the remedial design based
on requirements of the NR 400 series regulations (NR 404, NR 415, NR 419, NR 431, NR 440, and
NR 445) for paniculate matter and fugitive dust emissions that may result during soil consolidation.
Plans for controlling fugitive air emissions will be included in the Remedial Design. Any dust or
emissions from treatment systems, grading or other earthwork must meet the ambient air standards
for paniculate in NR 404, fugitive dust standards in NR 415, control of organic compound emissions
in NR 419, control of hazardous pollutant emissions in NR 445, and visible emissions standards in
NR431.
C. THE SELECTED REMEDY IS COST EFFECTIVE
The remedy provides overall effectiveness proportionate to its cost. The estimated costs associated
with this remedy are:
Capital Cost: $ 3.8 million
Operation and Maintenance Costs (net present worth): $ 4.4 million
Total Cost (net present worth) $ 8.2 million
Alternative 3 is considered cost-effective because it takes advantage of the site stratigraphy to
dewater the unconfined aquifer, remove the free phase LNAPL, and expose the residual LNAPL
smear zone to air. Alternative 3 also takes advantage of natural attenuation processes occurring in
the ground-water plume to remediate the less contaminated ground-water. The remedy provides
protection against the potential for future human health risks associated with exposure to site ground-
47
-------
water, and prevents human and ecological exposure to soil contaminants by placing them under a
cover. Natural degradation processes in the soil are enhanced with the addition of air to the
subsurface. Major capital costs associated with the selected remedy include installation of the
bioventing system and ground-water/LNAPL extraction system, constructing a lagoon support wall,
grading the slopes and revegetating the site, excavating and consolidating soils, removing the biopad,
and construction and engineering support associated with implementing the work. Major operation
and maintenance costs include the bioventing system operation (electrical costs) and the ground-
water /LNAPL recovery system operation (part-time operator and carbon exchange), subsurface soil
sampling at five-year site reviews, and semi-annual or annual monitoring and inspection.
The No-Action alternative is less costly, but it would not provide protection from the current and
potential future risks associated with soil and ground-water exposure. Alternative 2 (Soil Cover and
Ground-water/LNAPL Extraction) is less costly than the selected remedy. However Alternative 2
does not enhance the degradation of PCP in the soils or smear zone, appreciably extending the time
to meet remedial objectives within a reasonable time frame.
The selected remedy affords overall effectiveness when measured against CERCLA Section 121
diteria and the NCP*s nine evaluation criteria, and costs are proportionate to the protection that will
te achieved.
D. THE <»EI.FrTFn BKMF.f»Y UTILIZES PERMANENT SOLUTIONS AND
ALTERNATIVE, TREATMENT OR RF^O^RCE RECOVERY TECHNOLOGIES
TO THE MAXIMUM EXTENT PRACTICABLE
The selected remedy represents the maximum extent to which permanent solutions and treatment
technologies can be used in a cost-effective manner at the PWP Site. The remedy permanently
removes the contaminants from the natural environment in the following manner
Free-phase L NAPL is extracted from the water table and incinerated off site.
Extracted ground-water is treated with carbon and reinjected on site.
Bioventing of the exposed smear zone will enhance natural degradation of residual
LNAPL, and bioventing of the vadose soils will enhance biodegradation of PCP/oil
contamination. It is estimated that 80 to 90 percent of the estimated 120,000 pounds
of PCP will be reduced in 10 years of bioventing system operation.
Natural attenuation is also occurring in the ground-water plume, reducing PCP to
chloride, carbon dioxide, and water.
Highly contaminated arsenic soils will be solidified to prevent migration, and placed
under a cover to prevent direct contact. Less contaminated arsenic soils will be
consolidated under the soil cover to remove the direct contact exposure route, and
eliminate the ecological concerns.
48
-------
The selected remedy is protective of human health and the environment, complies with federal and
state requirements that are legally applicable or relevant and appropriate, and is cost effective.
LNAPL and highly contaminated ground-water source removal combined with bioventing of the
PCP/fuel oil contaminated soils, and monitored natural attenuation of the plume perimeter;
consolidation of sediments and soils under a cover; erosion control measures; environmental
monitoring; and restrictions to prohibit access to contaminated soils and ground-water through
institutional controls, will provide the most permanent solution practicable, proportionate to cost.
E. THE SELECTED REMEDY SATISFIES THE PREFERENCE FOR TREATMENT
THAT PERMANENTLY AND SIGNIFICANTLY REDUCES THE TOXIC1TY.
MOBILITY. OR VOLUME OF THE HAZARDOUS SUBSTANCES AS A
PRINCIPAL ELEMENT
The principal elements of the selected remedy are LNAPL removal, treatment of the grossly
contaminated ground-water with carbon, and enhancing natural biodegradation of the principal
hazard at the site, PCP. Biodegradation of PCP produces benign substances, reducing the toxicity
and volume of the principal site threat. Fuel components, such as benzene and naphthalene, will also
biodegrade with the PCP. Arsenic, copper, and to a lessor extent, zinc, are rendered immobile by
solidification, or consolidated in the CAMU, covered with soil, and fenced. This remedy addresses
the potential threat to human health and the environment by the restoration of the ground-water
resource by the permanent destruction of organic hazardous substances, and immobilizing the
metals. This will significantly reduce the toxicity, mobility, and volume of the hazardous
substances.
XIII. DOCUMENTATION OF SIGNIFICANT CHANCES
There are no significant changes from the recommended alternative described in the proposed plan.
V
49
-------
»CHAN UP OOAIJ MM CONtmUINTt OP ranNTIAL eONCMN M WML
PtNTA WOOD PRODUCTS MTI
TOWN Of DANMU, WISCONHN
•OMto
10*
MM
«0«
ir«
I AMAH NN TMill
net
TdMfW
Zno
II*
OOOOT
100
ir
toe*
2 I
18'
310
4 1"
if
OOOM*
too
If
100*
04*
01
IS'
JtO
41'
OOOM'
347
It*
too*
04*
40"
• I1
I.OM
41*
t I
I J
2 I
101
IK
Of. 714
211
171
It
40.100
4,707
I.IIT
4I.W3
1.117
2.7»
2.0M
130.077
4M.I33
14
U
17
43
If.ttt
M17
7.7W
0414
07>
41
71
•0
171
17.000
3,110
4.1*4
11.471
It
•37
37.014
lOt.lM
•7
7.7W
3.413
4.307
101.777
17
ON
1.411
130.000
214.700
1012
40.000
Ml
204.140
04t*
If
1.004
7.011
3.110
071
3,110
(3
11.043
IM.4ZO
23.404
01»-174
H-111
OH-U2
tt-347
»t
17
0037 111
lfr-2.007
0 037-4} 1
11-0.1
NA.
• PRO* lee nduttrul worttri. «etvtHen wwt»<» «nd t«wd*ni«l »^e*unM §rt MMd on MgMn IX PRO ifpnMob iMumng nowtion, ttwfetion md tfom«l
' Wacom* direol oontKI PRO* MMd on SPA MAQO PM 0 muMpto pMhMy i^roion lor te4 n«Mxf4«d m DM 7M 10
RCLi tot PAH* Mud en WONM Ouiotnc* SoM Ctotnup U»*« lof PAHt kiMdm OuHmei
' Owkgreund not a»mmin«d le» 14* OloliOfeund v»tu» • M**d en lh» (MM o» eone>nliilion» in to* ot «w UnMrt OJMM
ff>>m«n«Cono»»MririoniifiIo»«^O»i«yOu^e<^»^r«fii>»o^r^«Con»»m«* bt*f#*t «Kl M dKamrtmO it pert ol >n anig
• ten oono«itr«4iefl pieKclM el orounowoMf * t» loMM el •* «w pKomMrt eeniMMd
1 So* eonewWMiOM preMeWf* o< greundMlw era WHosniw Nft 7tO 00 TibUlvilytiloilhtiTlXi,
•Wt<>ri^M™t(>H>W^*rw4*^™*»&<*W*e9mDWgu#l-»***to?AHtlrt
M »M««v«n«>E T«HMf 1 lot J
Vihw la ta* r«vi»td taMd OB «M«on*l MM Hwttnowon end ttMMHHy MucV «*»,
t
'-in3 ill
-------
TABLE 2
PRELIMINARY REMEDIAL GOALS AND CLEAN UP GOALS FOR CONSTITUENTS OF POTENTIAL CONCERN IN GROUNDWATER
RECORD OF DECISION
PENTA WOOD PRODUCTS SITE
TOWN OF DANIELS, WISCONSIN
Compound
Arsenic
Benzene
Chloride
Copper
Ethylbenzene
Iron
Manganese
Naphthalene
Pentachlorophenol
Toluene
Xylene, mixture
Zinc
Clean Up Goals
(ufl/L)
5
0.5
125.000"
130
140
150b
25"
8
0.1
69
124
2,500b
Parameter* Considered in Setting PRGs for Groundwater
Federal MCLs
Primary MCL
-------
TASLI3
SUMMARY OP SITE P4SK TO HUMAN HEALTH
POTENTIAL PUTUfll SCENARIOS
RECORD OP DECISION
PINTA WOOD PRODUCTS SITE
TOWN OP DAMBLS, WISCONSIN
Expoeure Soeoeiflo
Residential
(unconflned welt)
TOTAL
Residential
(semteonflned welle)
TOTAL
Typical Woifcer
TOTAL
Construction/Excavation
Worteer
TOTAL
Expoewe Route
lA-Bl^AMeAl^l lafc4BAA4l4kM
incKMniw mgwiion
Dermal contact
IngesMon
|_k&-.|.tljuh
innwanon
Ingestton
Dermal contact
Incidental Ingestton
Dermal contact
Ingestion
Inhalation
Ingsstlon
Dermal contact
Incidental Ingestion
Dermal contact
Inhalation
Incidental Ingestion
Dermal contact
Inhalation
Medkjnt
SON
SON
Outdoor air
OroundwateMMW-lOe)1
Qroundwater(MW-IOa)'
SoH
SoN
Outdoor air
Qroundwater(MW-10a)(
Oroundwater (MW- 10e)'
Soil
Soil
Outdoor Air
SoH
Soil
Outdoor Air
Caooac Rtolca
SMawlde
RMB
1.71-04
1.11-04
B.M-06
5.4E-06
1.41-01
I.1B-01
1.11*00
1.71-04
1.11-04
5.61-06
5.4E-08
2.4E-02
3.4E-61
3.9E-01
1.H-06
i.4i-oe
3.2E-06
S.3I-06
3JE-06
3.6E-07
4.21-06
0.4E-06
Avenoe
1.M46
49t-0t
1.0E-4W
13E-06
2.61-02
4.1B-01
4.4E-01
1.6E-W
4.9l-0t
1. 01-06
1.3E-06
4.0E-03
4.6C-02
S^E-02
••
• •
~
••
-
Tfeaiiviefii AFea
RME
1 .31-02
3.01-03
3.01-03
4.41-06
1.41-01
9.11-01
1.11*00
1.31-02
3.01-03
3.0B-4B
4.41-06
2.4E-02
3.41-01
3.61-01
1.5E-03
•JE-04
2.6E<06
2.8E-03
••
••
A^fe^MaM^A
MvWfMV
1.31-02
1.41-04
861-04
10E-06
2.81-02
4.1141
4.U41
1.3E-02
1.41-04
6.61-04
10E-06
4.0E-03
4.61-02
6.61-02
••
••
••
••
••
HA>ivd Indl'^^1
SlftAHHiilA
^l^W^WW^^W
RME
0.60
007
0.19
100
1,700
1,600
0.8
0.07
019
16
270
290
0.11
0.03
••
0.14
0.56
0.01
••
0.67
A^aaupAj^A
MvlMVCJIl
0.23
001
0.12
M
1,100
1,200
0.23
0.01
0.12
6.6
170
160
• *
• •
••
••
••
• •
••
T ItMfVMfn AfWI
RUE
68
2
13
100
1,700
1,900
66
2
13
16
270
370
6.6
0.76
9.6
••
••
••
••
Average
19
0.3
6.3
M
1,100
1.200
19
0.3
6.3
6.9
170
210
--
••
-
••
Key:
'Exposure to groundwater assumes that domestic water Is derived from a maximally contaminated well.
•- • Not evaluated.
RME • Reasonable maximum exposure.
BOLD • Indicates calculated risk exceeds 1E-6 or HI exceeds 1,
MKE/IUal
-------
TABLE 4
SUMMARY OF SITE RISK TO ECOLOGICAL RECEPTORS
RECORD OF DECISION
PENTA WOOD PRODUCTS SITE
TOWN OF DANIELS, WISCONSIN
Receptor
Deer Mouse
Short-tailed Shrew
Raccoon
American Robin
General Location
Onsite Treatment Area
Onsite Nontreatment Area
Offsite Wooded Area
Offsite Wetland Area
Onsite Treatment Area
Onsite Nontreatment Area
OtfsHe Wooded Area
Offsite Wetland Area
Onsite Treatment Area
Onsite Nontreatment Area
Offsite Wooded Area
Offsite Wetland Area
Onsite Treatment Area
Onsite Nontreatment Area
Offsite Wooded Area
Offsite Wetland Area
Contaminant of Concern
Pentachlorophenol
9.750
25
163
2.0
319,100
824
5.318
66.5
5,238
13.5
87.3
33.3
47,409'
122
790
10.0
Arsenic
1.055
266
219
47.5
2.712
680
561
118.6
249
63
52
11.5
462
116
95
19.8
Copper
1,139
0.06
6.8
0.8
2.932
1.5
17.5
2.0
3,993
2.05
24
2.79
2.597
1.3
16
1.8
Zinc
50
0.34
0.34
0.08
126
0.09
0.09
0.20
83
0.06
0.06
0.14
4,341
3.3
3.3
7.5
MKE/TBL4.DOC
-------
TABLE S
PRELIMINARY REMEDIAL GOALS FOR CONSTITUENTS OF POTENTIAL CONCERN IN SEDIMENT
RECORD OF DECISION
PENTA WOOD PRODUCTS SITE
TOWN OF DANIELS, WISCONSIN
Compound
Arsenic
Penlachlorophenol
Copper
Zinc
Preliminary
Remediation Goal
(mo/kg)
9.6
0.4
31
120
Parameters Considered In Salting PRO* for Sediment
Summary of Concentrations Related to Effects to
Benlhic Organisms From Four Quldelinea*
Lowest Effect Level
Medlen Value (nig/kg)
9.6
31
120
Median Value (mo/kg)
40.5
154
428
Ecological PRQa Baaed on
ToiteHy Reference Valuea*
0.25-62.1
0.037-1.6
25-347
115-8,692
WeWffnflQtOn
99OlfV)9f1i
QueHty Value*
-------
TABLE 6
PRELIMINARY REMEDIAL GOALS FOR CONSTITUENTS OF POTENTIAL CONCERN IN SURFACE WATER
RECORD OF DECISION
PENT A WOOD PRODUCTS SITE
TOWN OF DANIELS, WISCONSIN
Compound
Arsenic
Iron
Manganese
Copper
Zinc
Chloride
Pentachlorophenol
Ammonia
Preliminary
Remediation
Goal
(raft.)
50
1.000
43"
524b
230,000
1.8e
Parameter* Considered in Setting PRG» for Surface Water
Federal Water Quality Criteria
Acute
Criteria
(M9/L)
360
-
105b
579"
860,000
Chronic Criteria
(ug/L)
190
1,000
57"
524b
230,000
1.8C
Wisconsin Water Quality Criteria
Threshold
Concentration for
Taste and Odor
(ug/L)
-
»
-
30
Acute
Toxicity
Criteria
(MO/L)
340
-
105b
579"
2.1"
f
Chronic
Toxicity
Criteria
(P9/L)
152
-
57"
524"
2.r
Human
.Cancer
Criteria*
(ug/L)
50
-
-
-
Great Lakes
Water Quality
Initiative
Chronic Criteria
(ug/L)
1,800
-
43b
580
1.8°
• -- • = No criteria.
* Human threshold cancer criteria for nonpublte water supply.
b Hardness dependent, criterion based on 660 mg/L hardness.
c pH dependent, pH 5.68 assumed.
" PCP acute toxtoity criteria * e (1.0054(pH)-4.877); at pH « 5.68, ATC= 2.1 ug/L (NR 105).
• PCP chronic toxlcity criteria = e (1.0054(pH)-4.9617); at pH = 5.68. CTC= 2.1 pg/L (NR 105).
' Ammonia surface water quality criteria are set for specific discharges based on temperature and pH of the receiving water.
NR 104.20 requires ammonia to be less than 3 mg/L in surface water.
MKBTbte 5&6.xts
-------
TAIL!7
COMPONENTS OF THE REMEDIAL ALTERNATIVES
RECORD OF DECISION
PINT A WOOD PRODUCTS SfTB
TOWN OF DANIELS, WISCONSIN
K9y vompofMfitf
No Further Action
Land UM Restrictions
Building Demolition
Dismantle Btopad and Backfill Onette
Grading, Lagoon Buttress, Revegetatton
Excavation of Hot Spots, Washout Gutty Soils
and Sediments and Consolidation
Fixation / Stabilization— Arsenic Contaminated
SoH and Consolidation
8oH Cover over ConsoWalad Sods end
Sediments
Natural Attenuation— Vadose SoUs
In 3ttu Bloventlng of VadoM Soils
In Situ Bloventlng of Dewatered Smear Zone
LNAPL Collection and Offstte Disposal
1
fc|M ••M*itA0
no runnw
Action
X
I
ftoll a^jmainliiflaiin n
end Cover, Ground
Water Mid LNAPL
C»llai»Aifte> — — ^
UINMJUMI iWICJ
Tm^^A^mmftt Aam^
rMfffWfn, •nQ
NfltllTM
AtttfMMntton
X
X
X
X
X
X
X
X
X
a
and Cover,
Water end LNAPL
Collection end
T_A^A^»AMft — — .J
lOTinwni, ano
Mafural AH*niiMftlMM
n«iiim Anenueiron
X
X
X
X
X
X
X
X
X
X
4
•nd Covtfi
Water end LNAPL
Collection end
Tree»riienl
Throughout Plume
X
X
X
X
X
X
X
X
X
X
8
Boll Consolidation
and Cover,
Bloventlng, end
Steam Infection
wrth Soil Vepor
Extraction
X
X
X
X
X
X
X
X
X
MKE/TBL7.DOC
10(2
C
-------
TABLET
COMPONENTS OF THE REMEDIAL ALTERNATIVES
RECORD OF DECISION
PENTA WOOD PRODUCTS SITE
TOWN OF DANIELS, WISCONSIN
Key Components
Ground Water Collection in LNAPL Area
Ground Water Collection Throughout Plume
Monitored Natural Attenuation — Ground Water
Steam Injection with SVE Collection
GAC Adsorption
Precipitation and Filtration
Discharge Via Infiltration Trenches (or)
Discharge to Doctor Lake
Environmental Monitoring
Maintenance of Cover and Erosion Control
Alternative Water Supply
Five-year Site Reviews
1
No Further
Action
X
2
Soil Consolidation
and Cover, Ground
Water, and LNAPL
Collection and
Treatment, and
Natural
Attenuation
X
X
x •
a
X
b
X
X
X
X
3
Soil Consolidation
and Cover,
Bloventlng, Ground
Water and LNAPL
Collection and
Treatment, and
Natural Attenuation
X
X
X
a
X
b
X
X
X
X
4
Soil Consolidation
and Cover,
Bloventlng, Ground
Water and LNAPL
Collection and
Treatment
Throughout Plume
X
X
X
a
X
b
X
X
X
X
5
Soil Consolidation
and Cover,
Bioventlng, and
Steam Injection
with Soil Vapor
Extraction
X
X
X
X
a
X
b
X
X
X
X
'Precipitation of iron and manganese may be necessary for discharge to Doctor Lake.
bDischarge to Doctor Lake will be considered if discharge limits result in more cost-effective treatment processes.
MKE/TBL7.DOC
2 Of 2
-------
TABLE 8
ARARs CRITERIA AND GUIDANCE FOR THE SELECTED REMEDY
RECORD OF DECISION
PENTA WOOD PRODUCTS SITE
TOWN OF DANIELS, WISCONSIN
Chemical-Specific ARARs
> Wisconsin NR 140-Ground Water Quality
•• Wisconsin NR 102 and 103 - Water Quality Standards for Surface Water and Wetlands
•• Wisconsin NR 720 - Soil Cleanup Standards
»• Wisconsin NR 404, 415, and 419 - Air Quality Standards
•• Safe Drinking Water Act (SDWA) - MCLs
- SDWA - MCLGs
* Clean Water Act (CWA) - Ambient Water Quality Criteria
»• Clean Air Act - National Primary and Secondary Ambient Air Quality Standards
The following chemical-specific criteria were also considered:
»• EPA Risk Reference Doses
»• EPA Carcinogen Assessment Group Cancer Slope Factors
•• EPA Health Advisories
* EPA Region IX PRO approach
*• EPA approach for addressing dioxin in soil memorandum
»• WDNR Soil Cleanup Levels for PAHs Interim Guidance
+ WDNR Sediment Quality Objectives
Action-Specific ARARs
»• Resource Conservation and Recovery Act
»• Wisconsin NR 500 Series - Solid Waste Management
»• Wisconsin NR 600 Series - Hazardous Waste Management, particularly NR 636, CAMU
provisions
»• Wisconsin NR 812 - injection of treated ground water; point-of-use water treatment devices
>• EPA and Department of Transportation regulations on transport of hazardous waste
» Wisconsin NR 700 (Investigation and Remediation of Environmental Contamination)
Location-Specific ARARs
> Executive Orders 11988 and 11990 - avoid adversely affecting wetlands
-------
SCAlEtJMUS
FIGURE, .
SrtelocotkxiMc^-'
Record of Decision
Penta Wood Products Ste
Town of Daniete. Wisconsin
-------
r
'c^fe^/ '• }i£-fi
"•> ** *_ '^y i i \ _ =-
0 200
SCAlE .NfSET"1
~\/-
Sr \\ : 'soumiw T~
'"
•tea
600
FIGURE 2
Site Features Map
Penta Wooa Pr.-xjucn S»»
Town ot Oan^iw VV.iconiln
- CM2MHHJL
-------
PROCFSS
BUIIT.IXQS
WOODDCBRIS
LAYER HOLDS
PCP OIL
PCP SOLUTE
MCVLfVlrNfVIA
PORF V.'ATER
OVERLAND
TRANSPORT OF SOIL
PCP OIL INTO
WETLAND
25J mg/Kg PCP
PCP Gil
LNAPL
30 my/Kg PCP I
94 5.000-110.000 ug/L PCP
97 4,300-30OX)UQ/L PCP
94 2.000-0 ug/L PCP
97 Oug/L PCP
94 110,000 ugA PCP
97 30X100 ug/L PCP
SEVl-«NFIfJED
SY!EM
94 017,000 UQ/L PCP
97 0-13,OOOUO/1 PCP
CC- MTAMIf JANT GROUNOWA7ER
TRANSPORT AS PLWACHUOWOPHUNATE
(SYSTEM pH - 7.2)
94 17,000 ug/L PCP
97 6.200 ug/L PCP
94 140 ug/L PCP
97 5 ug/L PCP
(UIMUOOI Cam
SOURCE: UB EPA Anc*flcal Contact *C*M4Q22,
WO.«03347-0«>a)l-002M)l FlgiM4.4-1,0*c«Tib«r I9M
FIGURE 3
Site Conceptual Model
Cross Section
Record of Decision
Penta Wood Products ate
Town of Dca' Wisconsin
JKIHILL
-------
emu IMI uum §. lie
•« mt mraa mm.
wet uun» • <* IWIMI. m
C ZMO
II «X>
FICURC 4
AND (997 PCP CONCENTRATIONS
CROUNONATER
i -no to imo («o
-------
t JIM
noun J
EXCAVATION ANC COVER AREAS
C
-------
APPENDIX A
WDNR LETTER OF CONCURRENCE
-------
WISCONSIN
DEFT. OF NATURAL RESOURCES
State of Wisconsin \ DEPARTMENT OF NATURAL RESOURCES
Tommy G. Thompson, Governor
George E. Meyer, Secretary
Box 7921
101 South Webster Street
Madison, Wisconsin 53707-7921
TELEPHONE 608-266-2621
FAX 608-267-3579
TOO 608-267-6897
October 15, 1998
Mr. William E. Muno, Director, Superfund Division
U.S. EPA Region 5
77 W. Jackson Blvd.
Chicago, IL 60604
SUBJECT: Concurrence on the Selected Remedy (Alternative 3) for the Penta Wood
Products Superfund Site, Town of Daniels, Burnett County, Wisconsin.
Dear Mr. Muno:
The Wisconsin Department of Natural Resources ("the Department") is providing you with this letter to
document our concurrence with the remedy selected for the Penta Wood Products Superfund site. The
final remedy, as outlined in the July 1998 Proposed Plan and the September 1998 Record of Decision,
will address the impacted soil and groundwater and is considered a final remedy for the site. The •
selected remedy, identified as Alternative 3 in the Proposed Plan and Record of Decision, includes:
Building Demolition
Segregation, solidification, and placement of all arsenic soils in a CAMU
Consolidation of PCP/Fuel Oil soils, sediments and wood chips under a soil cover
Bioventing PCP/Fuel Oil contaminated material
Biopad removal and backfill on site
Erosion control measures
Revegetation
LNAPL Removal
Grossly contaminated groundwater collection, treatment and discharge
Monitored natural attenuation
Institutional controls
Environmental monitoring and maintenance
Contingency measures to assure groundwater is restored within the specified restoration
time frame
Point of use carbon treatment or well replacement, if necessary
Five year site reviews
The costs and time frames for the selected remedy are estimated to be as follow:
• Estimated Time to Design and Construct = 2 Years
• Estimated Remedial Time Frame for soils above the water table = 10 years
• Estimated Remedial Time Frame to meet NR 140 PALs in groundwater = 30-40 years
Quality Natural Resources Management
Through Excellent Customer Service
-------
Mr. William E. Muno - 10/IS/98
Total Capital Costs = S3.8 million
Tool Operation and Maintenance Costs (net present worth) = S4.4 million
Total Costs (net present worth) = S8.2 million
We understand that the potentially responsible panics (PRPs) have agreed to a contribution but are not
able to fund the remedy and that die site remediation will be Fund Financed. It is understood that it
will be necessary for die state of Wisconsin to contribute 10% of die remedial action costs associated
with the proposed remediation (erosion control, soil consolidation and treatment, LNAPL removal,
Bioveming, grossly contaminated groundwater treatment and monitored natural attenuation).
It is also understood dial an evaluation will be done during die Five Year Reviews as to whedier or
not die remedy is performing as expected to restore groundwater to NR 140 standards widiin die
filimatcd restoration time frame of 30-40 years and to meet other remedial goals. In accordance with
Sections IX.B. 11 and 13. and K.C.3 of die Record of Decision (ROD), k is understood that U.S. EPA
will evaluate and. if necessary. implement additional technologies, such as steam extraction, direct
oxidation, pump and treat, etc.. to achieve the NR 140 groundwater standards widiin this estimated
restoration time frame in accordance witfi a contingency plan approved by both of our agencies. If a
Five Year Review determines dial it is necessary and feasible to implement more aggressive measures,
as provided in die ROD. it is understood that h will be necessary for die State of Wisconsin to
contribute 10% of any capital and O&M costs for die first ten years of the additional remedial action in
accordance wMh die cost allocation provisions of CERCLA and die National Contingency Plan.
We m»i«*Tin that NR 140 standards are technically and economically achievable for this site and it is
not likely that a CERCLA Technical Impracticability Waiver from those standards will be necessary.
It is further understood that 10% of die O&M costs for the first ten years of active groundwater
remediation and any contingencies and 100% of all O&M costs after die first ten years wfll be die
Stale of Wisconsin's responsftility. unless changes are made to CERCLA or die National Contingency
Plan dial would require an alternative cost allocation.
Until die final remedy is funded, designed and implemented, it may be necessary to implement erosion
control measures, to contain residual contamination and ensure die safety of die site. U.S. EPA staff
and DNR staff have agreed dial if the Department chooses to implement and fund such erosion control
measures, subject to the prior approval of U.S.EPA, the cost of such approved remedial erosion
control activities will be credited to die state's cost share for remedial action at die site. We expect that
this agreement will be formalized in die Superfund State Contract for die site, and we condition our
concurrence with die selected remedy for die site on reaching an agreement in die Superfund State
Contract on this issue.
We provide assurance of die State's willingness to provide the required State cost share on the
assumption diat U.S. EPA will assure that die PRPs will comply with their stipulated agreements and
all feasible enforcement actions against die PRPs will be pursued .
Nearly all contamination and remedial treatment residuals at Penta Wood Products have been
determined to be F032 or F03S listed hazardous waste. We understand diat if die Fund is expended to
conduct die remedy and if hazardous waste needing disposal is required to be managed off-site as pan
-------
Mr. William E. Muno - 10/15/98 3
of the remedy, that the State of Wisconsin will be required to provide the assurances for hazardous
waste management in 40 CFR 300.510 (d) and (e) of the National Contingency Plan. The assurances
are that a compliant hazardous waste facility is available, and that facility's use is consistent with our
approved Capacity Assurance Plan.
According to the September 1998 ROD for Penta Wood Products, a cornerstone of the final plan for
this site is the designation and acceptance of a Corrective Action Management Unit (CAMU). Chapter
NR 636 Wisconsin Administrative Code describes Wisconsin's requirements for our acceptance of the
design and performance of CAMUs and is an ARAR. Our acceptance of this final selected remedy is
contingent upon our acceptance of the CAMU design, construction and performance and consistency
with Wisconsin's hazardous w.aste program rules.
Our staff will continue to work in close consultation with your staff during the pre-design, design and
construction phases of the remedy. Thank you for your support and cooperation in addressing the
contamination problem at the site. Should you have any questions regarding this matter, please contact
Mark Giesfeldt at (608) 267-7562 or Tom Kendzierski at (715) 635^057.
Sincerely,
George E. Meyer
Secretary
cc: Tom Kendzierski NOR/Spooner
Gary Kulibert NOR/Rhinelander
Linda Meyer LS/5
Mark Giesfeldt RR/3
Mark Gordon RR/3
Gary Edelstein RR/3
Ken Glatz U.S. EPA Region V, 77 West Jackson (SR-6J), Chicago, IL 60604
-------
w
APPENDIX B
ADMINISTRATIVE RECORD INDEX
AND
ADMINISTRATIVE RECORD LOCATIONS:
BURNETT COMMUNITY LIBRARY
7451 WEST MAIN STREET
WEBSTER, WISCONSIN
U.S. EPA REGION 5 RECORDS CENTER
77 WEST JACKSON BOULEVARD
CHICAGO, ILLINOIS
-------
U.S. ENVIRONMENTAL PROTECTION AGENCY
REMOVAL ACTION
ADMINISTRATIVE RECORD
FOR
PENTA WOOD PRODUCTS INC.
SIREN, DANIELS TOWNSHIP, WISCONSIN
ORIGINAL
MAY 11, 1993
m_L.
i
2
3
4
5
6
DATE
04/01/86
08/00/90
01/22/91
02/13/91
01/16/92
03/00/92
AUTHOR
Vulcan
Chemicals
Aqua -Tech,
Inc.
Mockenhaupt ,
S., CRA
Kafura, D.,
WDNR
Mockenhaupt ,
S., CRA
Cones toga -
Rovers &
Associates
RECIPIENT
WDNR
Kafura , D . ,
WDNR
Mockenhaupt,
S., CRA
Kafura , D . ,
WDNR
WDNR
08/19/92
8 09/28/92
9 04/12/93
10 06/18/93
11 11/18/93
Hanson, R.,
Inter-County
Leader
Public
TITLE/DBSCRIPTION PAGES
Material Safety 3
Data Sheet,
Pentachlorophenol
Environmental 88
Assessment Report,
Phase III
Groundwater 12
Analytical Results
Correspondence re: 2
1/22/91 Analytical
Results
Analytical Summary 6
of Groundwater Data
Remedial Investi- 259
gation and Corrective
Action Plan
Newspaper Article, 2
"Alleged Pollution
Shuts Down Penta
Wood Products
Ramsey, W. ,
WDNR
Pastor, S. ,
U.S. EPA
E & E
Steadman, P. ,
U.S. EPA
U.S. EPA
Lesser, T. ,
U.S. EPA
U.S. EPA
Muno, W. ,
U.S. EPA
Preliminary
Assessment
SACM Team Trip
Report
Site Assessment
Action Memorandum
122
1
26
25
UPDATE fl
OCTOBER 15, 1993
03/19/93
03/23/93
04/23/93
05/03/93
Parkinson, A. ,
WDNR
Dunn, J. ,
WDNR
Parkinson, A. ,
WDNR
Parkinson, A. ,
Recipients
Kafura, D. ,
Michaelsen,
M. , WDNR
Recipients
Recipients
Memo re: 3/19/93 2
Conference Call
WDNR's Review of 4
the RI and Corrective
Action Plan (Draft)
Agenda for 4/29/93 4
Conference Call
Memo re: 4/29/93 3
-------
NDNR
Conference Call
Penta wood AR
Update il
Page 2
S 05/14/94 Parkinson, A.,
NDMR
6 OS/30/93 Parkinson, A..
NDNR
7 06/14/93 Parkinson, A..
NDHR
8 06/25/93 Steadman, P.,
U.S. EPA
9 07/14/93 Nilliams. R.,
U.S. BPA
10 08/20/93 Johnson. D..
NDNR
Williams, R.,
U.S. EPA
U.S. EPA
Parkinson, A.,
NDNR
8^mwa^m>B^BMBmwBB\A
Steadman, P. ,
U.S. EPA
Recipients
Recipients
Letter re: Pathway
Sampling
Memo re: Site
Strategy
Agenda for 6/15/93
HHK
1
1
6
Meeting, with
Attachments
Letter re: Request
for ATSDR's Hazard/
Risk Evaluation of
PCP, Arsenic and
Copper in Soils
ATSDR's Record of
lie mo re: Geologic
and Hell Data
03/08/95 Steadman. P.,
O.S. EPA
UPDATE 12
MARCH 8, 199S
Adamkus, V..
U.S. EPA
Action Memorandum:
Ceiling Increase
35
-------
U.B. EPA ADMINISTRATIVE: RECORD
REMOVAL ACTION
PENTA WOOD PRODUCTS SITE
SISEN, BURNETT COUNTY, WISCONSIN
UPDATE #3
12/04/96
Ti'LE •DEB:* ICTia;<
00/00/00 Penta Isaod :''Qducts,
Inc.
Brochure: "Cheuonite Pressure Treatasnt
Protects Mood Products'1
00/00/00 U.S. EPfi
File
Excerpts front "Field flppiicaticr-s of
Bioreiediation"
31
00/00/00 U.S. EPA
00/00/00 U.S. EPA
01/22/91 Koctenhaupt. S.,
Ccnestoga-Rovers
Associates
File
File
5 04/01/86 Vulcan Chemicals File
Site Securing List
Table: List of Topics! Contaminants
Identified Hithin the Penta Wooo Site and the
Range of Calculations
Material Data Safety Sheet for
PentacMorophenol
Kafura, D., WDNR Letter re: Groundxater Analytical Results
02/13/91 Kafura, 0., HDNR
tockenhaupt, S.,
Conestoga-Rovers 4
Associates
Letter re: Saiplmg Paraneters at the Penta
Hood Site
03/00/92 Conestoga-Rovers 4
Associates
U.S. EPA
Reiedia! Investigation and Corrective Action.
Plan
259
08/19/92 Hanson, R.,
Inter-County Leader
Public
10 09/28/92 Ramsey, U., UDNR HDNR/U.5. EPA
Newspaper Article: "Alleged Pollution Shuts
Down Penta Wood Products"
Preliminary Assessient Narrative for the
Penta Mood Products Site N/Attachients
211
11 03/04/93 Slat:, K., U.S. EP»
Steadian, P.. U.S.
EPA
Heiorandu* re: Analytical Methods for the
Penta Hood Site
03/19/93 Hei«er. E., U.S.
EPA/TSS
Steadian, P., et al;
U.S. EPfi
Meiorandua re: Potential Ecological Risks
13 04/12/93 Pastor, ^., l\.S.
EPA/CRC
14 05/12/93 U.S. EPA
15 06/25/93 Steadian, P.. U.S.
EPA
Lesser, T., U.S. EPA Trip Report: April 2, 1993 FenU Wood Site
Visit with SACH lean
File
Wiliians, R.,
JSDHH3/USPHS/ATSDR
Site Sketch of the Penta Wood Products Site
flenoranduj: re: U.S. EFfl Request-for
Hazard/Rise Evaluation cf c'entachiorophenoi,
Arser.ic and Copper in Soils at the Penta liooc
Products Site a/Attached Jul? 13, 1993 ATSDF.
Record of Act:vit;
-------
!::»
PA
e',tj dsc-i s s€srcrse tc
-" Eec'.ie* Ivs 'rter
lode: £=
. 4..
.ft:?' '»: S*:
3urmq *>e June 199? rc
Iispettic1-
cite
. F.. ii.5. r«tc'*. I.
Letter re: 1.5. E?f s Request for
Identi'iutiafl o' fiFSRs *c-r ihs Penta
Product1. £:te
Pirli^son. A.. MMr fidires&ee*
t: Faifits of D;s
isra: Dec;sicfl Tea* Prese^tatior. |FJ-?TICVc
3F THI; I-G:5WEin HAVE BED* REDV^ESi
21 lH12/~ U.S. EPA/ORt
iJ.S. CPU
Report:
Tec^.ici". Assistance
;£7K7* Hoed ^rese-yin^ Site
It- la/73 Alien, t. »nt -..
P-i'ce. L.S. ffi
StCitear. F., J.S.
'e: ErT Proxsai f-:' Support cf
i: ^he centa Mco< Products Site
EF;
for i SeHe Pert a teed Products, inc. Site
,?30TIWS OF THIS WXK.V KAVE E£EK
:« 11'18/TJ Steadwi. P.. J.S. J.S. EP* ?8T
EPA; et ii.
re: Eifcjtire Sufl«arr for the
Pent* Hoed Products SACK Site
Steatean. ?.. t'.S. J.S. EPS EOT
EFA: et »I.
re: Briefing ilno fc-- the Pent a
Mcod P-rdtcti S«C«I Site
!4 i:/15/»: traub. J.. J.S. E»« File
re: Regional Decision Ten
Str.leg) Approval for the Fenta Hood Products
3O Site
-
. C.,
EPA
Cover Letter ror«jrii;rc the Action Neiorandut
-------
DATE
AUTHOR
SECIPIENT
30 Ol.-124/!»s Farluflacr:, A., WDNR Addressees
31 01.'28/94 U.S. EPH'USHER U.S. EFft
32 01/31/94 Steadtan, P., L'.S. Leech, T., IRC
Epfl Corpo-ation
3; -02/03/94 Steadnan, P.. U.S. Lee, R., Village of
EPA Siren
ftewranduii re: rhinites of January 19, 1??3
cite HEsessfiBnt Teaa Conference Cali Meeting
34 03/00/94 U.S. EPA/HDNR
Public
35' 03/00/94 Roy F. tteston, Inc. U.S. EPA
36 03/17/94 U.S. EPA/HDNR Addressees
37 03/21/94 Rivera, R., U.S. EPA U.S. EPA/SAT
38 03/22/94 U.S. EPA/NDNR Public
39 04/00/94 U.S. EPA/OERR U.S. EPA
40 04/07/9* Parkinson, A., MNP. U.S. EPA/SfiT
41 04/08/94 Nied, «., U.S. EPA Addressees
42 04/15/94 Allen, H., et al.; Nied, H., U.S. EPA
U.S. EPA/ERT
43 04/15/94 Nied, H., U.S. EPA Addressees
44 04/22/94 Allen, H., et al.; Steadean, P., et
U.S. EPA/ERT al.} U.S. EPA
ndu« r°: Expectations for c'jl'. 5
I«pienenietion o* 8AC« iCSKER Directive
9203.1-13}
Cover Letter For«arding June IE, 1593 Site 1
Assessaent Report
Letter re: Notice of U.S. EPA Actions in 3
Siren under CERCLA
Fact Sheet: 'Cleanup Begins at Penta Wood :
Products"
Quality Assurance Project Flan (Revision 2j 31
Agenda for the torch 17, 1994 Site Assessment J
Tear. Conference Call Meeting
Highlights froi the March 17, 1994 Site :
Assessment Teat Conference Call Meeting
(PORTIONS OF THIS DOCUMENT HAVE BEEN
REDACTED:
Draft Agenda for the March 29, 1994 Penta !
Hood Products Site Environmental Cleanup
Public Meeting
Engineering Bulletin: "In Situ Biodegradation It
Treatment" (EFA/540S-94/502!
Memorandum re: March 30, 1994 Fer.ta Hcod Site ;
Assessment Teai Conference Call Debriefing
of Public Meeting
POLREP II (Initial) :
Memorandum re: ERT Activities at the Penta \
Wood Products Site for the Period Apr:! 11-
16, 1994
PDLREP 12 ]
Nemoranduii re: ERT Activities at the Fenta \
Hood Products Site for the Meek of April l7-
22. 1994
-------
'AcEI
r»io'iridu« re: *sr:: ~"i. 19*4 Site A
.-;•;-.:*
LeMer r?: J.5. EFA'e 5io<-f*e::a'-ion Fie-e
or i' the
K. L.5.
l.j 1/.3. E?«
vt re: fcti.ities at the Penta Kood
3:te »D- the t-e'ic
•3 .-i.;s;o4 KIM.
FDLRE?
=
rart S*wet: "Cleinap "regresses at Pent* Hooc <
F'odjcts Site*
U.S.
L.s. EPS
: Remedial
05 03/94 M.S. EP»/K;
b.3.
ERD Mee»: Peport for the Utt* Eadinq
I'.S. EPfi'EFT
?riace, 6., et
l.S.
Ssi!
(taps
i. f.. et ai: HeMrandu* -e: E?T Activities at the Penta
I.E. EPA MODI* Products Site for the Perioi fa; 1-lla
55 OVtt'94 Parlinson. «.. WW U.S. FA/SAT
, I.t U.S.
. 5.. U.S.
letorandui re: fa> 5, 1994 Fenta Hood Site
'eat Conference Cal: Seeling
re: Reco*terde
-------
DOCI G4TE AUTHOR
&1 -;-6/0?/?4 Pnn:e, G.. L.S.
E?A.'ERT .
Steadtar, F., et
al.; U.E. Eri
Heaior3ndu» re: Draft Tables and Figures
Generated froti the Extent :>f Ccrtanir:aticr
and Engineering Studies -April-Ma?, IV?*;
and Presentation cf a Conceptual Design for a
Pilot Study w/Attacfcsents
41 Ofc/13/94 Parkinson, i., WDNR U.S. EFfl
r: re: SUBBST-/ cf June 7, 1994 Per.ta
Mood Site ft«5ess»efif. Teja Conference Call
heetinq iPORT IONS OF THIS DOCUMENT HAVE PEEK
REDACTED)
i3 ji/23/9* Allen, K., U.S.
EPAVERT
SteaiJ«an, c'., U.S.
EPA
06/27/94 ParUnson, A., »1DNR U.S. EPA/SAT
c: 07/01/
-------
:•;;* T^TE
Veril. *.. -j.H.
^e? a: 'er.ta Mood frsducts
ra'tat. 3., j.;. Efi :.eii«*r..
0»/3$/9« it.S. EPA
•8 ;::v//5t H.S.
71 i; 3->-c« a. 3. EPS
fcusin. »"., rt al.: iliils. J..
latLonil Eftvironwft-
tal Test:rn. In:.
F;I T'j'.5«ittil -e: -.'.at Scale :AEi«!E«
FiC'«»-:.jt:ofl E-etanstrcticn- An iitsciicitec
Ctart: Set«i'::ng «ste "fate'iai at t^e Fenta
Hood =:'.» a-: oz SectwiK- ". :994
'art Sh«e»: '"lessi.? frogress at Prta itocfi
Products :.tf'
l c« Sc.-etber 3v.
Product; usiate
3ual:t> :--tro'i
Satple;
Sater T
31 )J.f«;»5
6: 0:/97/»5 leqoett, A..
EP*
64 C-S/00/7S
-'• ttKtoe. I
Stat-.s 1cr t*e ferts BCK:
to Er..ira?«er*.il tapt
CVJ»K. S.. U.S. t?S »«ort: ?;Jot Stucj Lti
r«nqus t** Fe«»ti Baod
. V.. j.S.
U.S. t?fi/Er
ttno:9* Soy F. itestor.. I-:. J.S.
Mhite
Site
Articf VtorjTitfua: Request fcr Ceihrs
Increase a-id for an Exetpt.ar ti the t2
»ii::oT. and K Worth Statutory Liiit for the
liM-tr:ti:a': Se«o«i! Action «t the Per.ta
Uocd Projects S.!e
3:te Cha'-irte'intio-' riral Report: Eite'.t o1 151
On -and C'4f E:te Contaunaticn Sfficiai and
Hear Su'<4;e Soil at the Pe-ta Hooti P'wJacts
Site 'VclbK : of 3: Text. Tat-es 3*u!
Site C^aracte'•l^«tlo• Final cepcrt: E/tent o* ""10
Or ani 0" Site Contaiinatio- Surfnial arc
Near SL-'JCP Scii at the PeM.a Hooi Prciucts
i:t» (Volute 2 2* 3: Aypen4i:e< ft-t;
-------
DO:* ?A;E ftUTKOF RECIPIENT-
3c 05OO/95 for F. Westor-, Inc. L'.S. EPA'ERT Site OaractE'irsh-j- Final Report: Extent j< i30
r^ j - Or iriti Off Site Ccntarinaticr.-Surficial an.c
^"^ • Near Surface So:! at the Penta Wood Prod'j:t«
:ite (Voaee 3 o* 7: Appendices I-F)
*
37 05/31/95 Ray F. ileston, Inc. U.S. EPA Technical Sesorandja: Pisrejiediati::1 Activitr 55?
SuMiary fcr the Fenta «ocd Procucts Site
*
3S 06'00/95 E:a!oqj and U.S. EPA Final Comuriit/ Involve-nent Piar 3i
Environment, Ire.
S' 06/00/95 Roy c. Heston. Inc. U.S. EPA Phase II Anended Quality A5surar.ce Wort Plan 6!
CJNSiGNEIl)
90 06/06/95 Walls, J.. Nied, il., U.S. EPA Letter Poniarding Attached Original Reports 110
Environnentcl for Saapies Collected July 7, i9?<
Guahty *1anageient,
Inc.
91 06/09/95 Steadian, P., U.S. Graeber, J., Letter Fomardng Attached Invoice Jar 3
EPA Environsentai ftdditionai Laboritory analytical Services
Duality Hanagenent,
Inc.
92 07/00/95 U.S. EPA Public Fact Sheet: "Questions fe Answers Concerning 4
the Penta Hoed Products Site'
4 J D3 08/16/95 Jergens, E., Steadian, P., U.S. FAX Transmission re: Transportation and 4
^^ . Environaenta! EPA Disposal Sumeary for the Penta Wood Site
Quality Nanageient,
Inc.
94 03/29/95 Jerqens, E., Steadsan, P., U.S. FAX Transmission re: Updated Transport aid 5
Environmental EPA Disposal Suniary
Qualit/ llanagement.
Inc.
95 08'30/
-------
:i» :* E «.•••»>-
re;e"rtit:;r and r:£:c££l c*
. J.. ;tej?tar>. :.. !J. = . Lett"' '?: lar-rt itiias af
IK.
. E.. ateaJiir.. f.. J.!. .ette' re: Stit^s Sepcrt a* t*«e 1
trfi :ransp
Inc.
3a* f. Meston. *.c:. j.5. EP*
uMtr. f?r the ^er:ta iCood Products Si
!:3 i;/rr/"5 loan. J.. Eauran- Steadsan, F.. U.S. Lette' Fo'ujrdioq ftttarhH Hest:« Cor^ectire :
Viaqenent. !~c.
104 :>>^:.^b latura. ft., tt* kied. V.. U.S. EP» FM Innsfission re: Perc7 9?'ls/?e Pa«!er, S. and 5. Public Letter re: c?azte 3r Cleancp Actitities at
Steadtar,, U.S. EP« ttie Perti trocd Site
J06 -M/74/91 le«v«tt ^Dttnt/ Publi: »ewpiper Vticle: '"erti La»?-jit 5«ttle4*
Sentinel
, ».. U.S. Addressees
EM
. E., toy F. at«a4w, p., U.S. trelnmarf Inc'^wics uit» S-jHtr; Report
, Inc. E"
-------
DOi* D-5'E AUW. REC'PIEir T'TLE'DESCfiFTIM pfitEE
!•: Oa/lO/94 Ssbn, D., WfiR L:.E, EPS ' Eii; of Lading: Waste Gil Nor. Hazardous Nor 1
A, J ErnironiW'tji Regulated
^* Services
112 06; 10/96 IDEd U.S. EPA Un;for« Hazardous liast? Manifests far tRe 95
Period «a> 10-June 10, 1996
113 06/i2/96 Slater, 5., Burnett Public Newspaper Article: "Penta Cleanup Continues: 2
County Sentinel EPA Official See; Light at tre End of the
Tunnel1
114 Ot/12/96 Hanson, R., Dublic Newspaper Article: "Super'und Cleanup at I
liter-County Leader Penta Vaoi Entering *ie»» Phase"
115 06/12/96 MDNR U.S. E^H Uniform Hazardous Waste Hanifests for the 6
Period January 29-June 12, 1996
116 O6.;l"f/9i Steadnar-, P., U.S. Fi'e Bovernnent ^roperty Dispositicn Docuaent 1
EPA
117 06/19/96 Doan, J., Environ Steadaan, P., U.S. Analytical Report for -enta Wood RFW Lot 6B5
*ental Quality EPA 96066508
Nanageient, inc.
118 •)o/:i/96 U.S. EPA Public EnvironienUi News ftelease: "EPfl «aies Sen 2
Superfund Sites in ffidwest"
-------
U.S. ENVIRONMENTAL PROTECTION AGENCY
REMOVAL ACTION
ADMINISTRATIVE RECORD
FOR
PENTA WOOD PRODUCTS SITE
SIREN, BURNETT COUNTY, WISCONSIN
UPDATE #4
JULY 7, 1998
NO.
1
DATE
01/08/93
04/00/93
08/22/94
AUTHOR
U.S. EPA
U.S. EPA
steadman, P.,
U.S. EPA
RECIPIENT
File
File
Rollins, F.,
U.S. EPA •
TITLE/DESCRIPTION PAGES
Record Book: OSC's 54
Log Containing
Information on Penta
Wood Site from January
8, 1993 - June 10, 1996
w/Attachments (Receipts,
Business Cards)
Seminars: Bioremedia- 288
tion of Hazardous Haste
Sites: Practical
Approaches to Implemen-
tation (EPA/600/K-93/002)
Soil Volume Estimates 4
for PCP and Arsenic
for the Penta Wood
Products Site
08/30/95
12/00/95
03/04/96
04/11/96
05/00/96
06/03/96
Karl, R.,
U.S. EPA
U.S. EPA/
OSWER
Hemming, B.,
Microbe Inotech
Laboratories,
Inc.
U.S. District
Court/Western
District of
Wisconsin
SoiJ and
Groundwater
Cleanup
Lundequam, V.,
Penta Wood
Products,
Inc.
Dietrich, D.,
U.S. EPA
U.S. EPA
Steadman, P.,
U.S. EPA .
File
U.S. EPA
On-Scene -Coordinator's 25
Report: Removal Action
at the Penta Wood
Products Site (DRAFT)
Report: Presumptive 59
Remedies for Soils,
Sediments, and Sludges
at Wood Treater Sites
(OSWER Directive 9200.
5-162)
Pamphlet: Bioremedia- 17
tion Testing Information
w/Cover Letter
Consent Decree re: 36
Penta Wood Products
Site
Publication: Bio- 74
remediation Issue
(May 1996)
Handwritten Log of 11
Activities for the
Period May 9-June 3,
1996
-------
P*nta Wood AR
HO. DM*
10 06/12/96 U.S. EPA
RECIPIENT
File
TITLE/DESCRIPTION
Federal On-Scene
Coordinator's Report
(DRAFT)
II 06/H/96 WDNP
State of Wisconsin
Uniform Hazardous
Waste Manifests for
U.S. EPA Penta Wood
Products
13
07/01/96
08/15/96
08/21/96
08/21/96
16
17
08/26/96
08/29/96
Steadman, P.,
U.S. EPA
State of
Wisconsin
Department
of Health
and Social
Services
Dumelle, R.,
U.S. EPA
Dumelle, R.,
U.S. EPA
Pastor. S..
4 P. Steadman,
U.S. EPA
Ramaly, T.,
Ecology and
Environment,
Inc.
Distribution
List
Steadman, P.,
U.S. EPA
Gzeber, J.,
Environmental
Quality
Management,
Ire.
Gceber, J.,
Environmental
Quality
Management,
Inc.
Public
Nabasny, G.
U.S. EPA
Final Pollution Report
(POLREP 132) for the
Penta Wood Products Site
Information Mailing re:
Role of Health Assessors
and Educators from the
Environmental Agency
Perspective
Letter re: Financial
Monitoring Review Finding
No. 4 - Over "Billed Costs
for a Fixed Rate Equipment
Item
Letter re: Financial
Monitoring Review Finding
No. 6 - Non-Compliance
with Other Direct Cost
Allocation Policy
Letter re: Update on
Cleanup Activities at
the Penta Wood Products
Site (UNSIGNED)
TDD Amendment Request
for the Penta Wood
Products Site
18
19
20
08/30/96
08/30/96
09/12/96
Ramaly, T.,
Ecology and
Envi rcrunent.
Inc.
Lundequam, V.
Penta Wood
Products,
Inc.
Ecology i
Environment,
Inc.
Steadman, P.,
U.S. EPA
U.S. EPA
U.S. EPA
Letter re: Draft OSC
Report for the Penta
Wood Site
Handwritten Log of
Activities for the
Period July 9-August
30, 1996
Technical Direction
Document (TDD) for
Removal Support at the
Penta Wood Products Site
-------
NO. DATE
AUTHOR
RECIPIENT
21 09/18/96 Liszewski, C., Lundequam, V.
U.S. EPA
Penta Hood AR
Update »4
Page 3
TITLE/DESCRIPTION
PAGES
Letter re: Change in
Office of Regional Counsel
Contact for the Penta
Wood Products Site
22
23
24
25
09/26/96
09/30/96
10/08/96
10/08/96
Ramaly, T. ,
Ecology and
Environment,
Inc.
Nordine, J.
4 T. Kouris;
Ecology &
Environment,
Inc.
Steadman, P.,
U.S. EPA
U.S. EPA
Na'basny, G.,
U.S. EPA
Nabasny, G.,
U.S. EPA
Young, M.,
Wisconsin
Division
of Health
Reidel
Envi ronmental
Services •
TDD Amendment Request
re: the Penta Wood
Products Site
Letter re: Extent of
Contamination Survey
for the Penta Wood
Products Site (DRAFT)
Letter re: Residual
Contaminant Level
Information Request
for the Penta Wood Site
Amendment of Solici-
tation/Modification
of Contract for the
Penta Wood Products
Site
26 10/22/96 Nabasny, G.,
U.S. EPA
File
Technical Direction
Document (TDD) re:
Removal Support at
the Penta Wood Products
Site
27 10/22/96 Liszewski, C., Lundequam, V.
U.S. EPA
28
29
30
31
10/24/96
11/15/96
11/15/96
02/11/91
McCarrin, M.,
Clayton
Envi ronmental
Consultants
Nordine, J.
& T. Kouris,
Ecology &
Environment,
Inc.
Ecology &
Environment,
Inc.
Jergens, E.,
Environmental
Quality
Management,
Inc.
Steadman, P.,
U.S. EPA
Nabasny, G.,
U.S. EPA
U.S. EPA
Steadman, P.,
U.S. EPA
Letter re: Treating 2
Cylinders at the Penta
Wood Products Site
Statement of Qualifica- 72
tions Package w/Cover
Letter
Letter Forwarding
Penta Wood Products
Site Extent of Con-
tamination Survey
Draft OSC-Report 23
Outline for the Penta
Wood Products Site
CERCLA Offsite Disposal 40
Report for the Penta
Wood Products Site w/
Cover Letter
-------
Pent* Hood t
MO. PACT APTBO* BSCIPIKNT TITLE/DK3CRIFTIOM
32 03/21/97 Grebe r, J.. Steadmar., P., Letter Forwarding 107
Environmental U.S. EPA Contractor's FINAL Site
Quality Report foe the Penta
Management, Wood Products Site
Inc. w/cover Letter
-------
N6.
1
2
DATE
06/00/95
08/00/97
06/00/98
06/00/98
06/00/98
06/29/98
U.S. ENVIRONMENTAL PROTECTION AGENCY
REMOVAL ACTION
ADMINISTRATIVE RECORD
FOR
PENTA WOOD PRODUCTS SITE
SIREN, BURNETT COUNTY, WISCONSIN
UPDATE #5
JULY 7, 1998
AUTHOR
Ecology and
Environment,
Inc.
Ecology and
Environment,
Inc.
CH2M Hill
CH2M Hill
CH2M Hill
Kendzierski,
T., WDNR
RECIPIENT
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
U:S. EPA
GlatZ, K.
U.S. EPA
TITLE/DESCRIPTION
Final Community Involve-
ment Plan for the Penta
Wood Products Site
Report: Focused Human 115
Health Risk Assessment
for .the Penta Wood
Products Site
Report: Screening Level 70
Ecological Risk Assess-
ment for the Penta Wood
Products Site (FINAL)
Remedial Investigation 497
Report for the Penta
Wood Products Site (FINAL)
Feasibility Study Report 320
for the Penta Wood
Products Site (FINAL)
Memorandum re: WDNR' s 2
Comments on the June
1998 Draft Remedial
Investigation Report for
the Penta Wood Products
Site
GUIDANCE ADDENDUM
THE FOLLOWING DOCUMENTS ARE INCORPORATED INTO
THE ADMINISTRATIVE BY REFERENCE
DOCUMENTS HAVE NOT BEEN COPIED FOR PHYSICAL INCLUSION
INTO THE ADMINISTRATIVE RECORD
DOCUMENTS MAY BE VIEWED AT:
U.S. EPA REGION 5
77 W. JACKSON BLVD.
CHICAGO, IL 60604-3590
00/00/82
U.S.
Geological
Survey
Siren West, Wisconsin
Quadrangle Map (SW/4
Webster 15', N4545-
W9222.5/7.5)
-------
NO. DM
AUTHOR
3 10/00/88 U.S. E?A/
OEPR
RECIPIENT
U.S. EPA
9 00/00/89 U.S. EPA
10 03/00/89 U.S. EPA
11 03/08/90 U.S. EPA
12 03/25/91 U.S. EPA
13 00/00/93 U.S. EPA
14 00/00/94 USDHHS/USPHS/
ATS DP
15 02/00/96 U.S. EPA
16 06/00/97 U.S. EPA
Prnta Wood AR
Update •
Page
TITLE/DESCRIPTION PAGES
Guidance for Conducting
Remedial Investigations
and Feasibility Studies
Under CERCLA (Interim
Final) [OSWER Directive
9355. 3-011
Risk Assessment Guidance
for Super fund: Volume 1
(Human Health Evaluation)
Risk Assessment Guidance
for Super fund: Volume 2
(Environmental Evaluation
Manual;
National Oil and Hazardous
Substances Pollution
Contingency Plan (Final
Rule) [55FR8666]
Risk Assessment Guidance
for Super fund: Volume 1
(Human Health Evaluation
Manual: Supplemental
Guidance, Standard Default
Exposure Factors)
Wildlife Exposure Factors
Handbook: Volume 1 of 2
(EPA/600/R-93/187a)
Toxicological Profile for
Pentachlorophenol
Drinking Water Regulations
and Health Advisories
Risk Assessment Guidance
for Superfund: Process
for Designing and Conduct -
ing Ecological Risk
Assessments
00/00/98 U.S. EPA
19 00/00/98 U.S. EPA
Integrated Risk Informa-
tion System (IRIS)
Health Effects Assessment
Summary Tables (HEAST)
-------
NO.
19
20
DATE
01/00/98
04/13/98
AUTHOR
U.S. EPA/
ORD/OSWER
U.S. EPA/
OSWER
RECIPIENT
U.S. EPA
U.S. EPA
Penta Hood AR
Update #5
Page 3
TITLE/DESCRIPTION PAGES
Steam Injection for Soil
and Aquifer Remediation
Memorandum: Approach for
Addressing Dioxin in Soil
at CERCLA and RCRA Sites
(OSWER Directive 9200.4-
26)
-------
U.S. ENVIROMCNTAL PROTECTION AGENCY
DATE
07/3C/93
•38/3S/98
ADMINISTRATIVE RECORD
FOR
PENTA WOOD PRODUCTS SITE
SIREN, BURNETT COUNTY, WISCONSIN
UPDATE 16
10, 1998
AUTHOR
Ker.ar . -?r;
Northwestern
Court
Reporters
Kendz:erski,
T. . KRII3
Kencz.ersKi.
T.. W^r.P
RECIPIENT
31=", r . ,
U.S. S PA
G-atZ, .«..
U.S. EPA
Glat=, K.
U.S. EFA
Letter: iOXF's Comments
an 'he Beireazal Inves-
tigarac?.-: Weporr for the
Perita "rfood Products Site
Transcript of July 15,
199B Public «eeting re:
the Proposed -Plan for
the Per.ta Wood Products
Site
Letter: KDNR's Coinments
on tile Feas^biJjty Study
for the Per.ta Wood
Products Site w/ Attach-
ment
Letter: KDNR'-s Comments
or. the Proposed Plan for
the Fer.ta b'cod Prodjcts
Site
-------
APPENDIX C
RESPONSIVENESS SUMMARY
OVERVIEW
The public participation requirements of CERCLA sections 113 (k) (2) (B)) (i-v) and 117 of
CERCLA have been met during the remedy selection process. Section 113 (k) (2) (B) (iv) of
CERCLA requires the U.S. EPA to respond "to each of the significant comments, criticisms,
and new data submitted in written or oral presentations" on a proposed plan for a remedial
action. The Responsiveness Summary addresses concerns expressed by the public and
governmental bodies in written and oral comments received by U.S. EPA and WDNR
regarding the proposed remedy for the PWP Superfund Site.
BACKGROUND OF COMMUNITY INVOLVEMENT
W'
The following is a chronology of community relations activities to date:
Fact sheets were issued in March and May, 1994, to explain the start-up and progress made
during the non-time critical removal. The March 1994 fact sheet was developed by the WDNR
in cooperation with the U.S. EPA. WDNR hosted a public meeting on March 29, 1994, to
explain the beginning stages of the cleanup.
U.S. EPA met with several local residents, representatives from various town boards, and a
representative from the Burnett County Health Department on April 11-13,1995, to identify
community concerns and interests regarding the PWP Site.
Community Relations Plan (CRP) was prepared based on concerns and interests generated
from community interviews in June 1995.
U.S. EPA published two public meeting notices in the Burnett County Sentinel and Inter-
County Leader to discuss cleanup activities under the removal program, and to announce the
meeting. Fact sheets were distributed to inform the community about the cleanup and provide
background on the PWP site. A public meeting was held on November 30,1994.
A press release was sent to area media announcing that the PWP site had been listed on the
NPL (June 1996).
\Hjt The RI, FS, and Proposed Plan for the PWP Site were released to the public on July 1,1998.
-------
Public Notices were placed in the Burnen County Sentinel and Inter-County Leader on July
1.1998.
The public comment period was held from July 7 to August 8.1998.
A public meeting was held on July 15. 1998, to discuss the FS and Proposed Plan.
Representatives from U.S EPA and WDNR answered questions about the PWP Site and the
proposed remedial alternative. A transcript of this public meeting has been placed in the
Administrative Record. Written comments were solicited at the meeting. Approximately six
people attended, including local residents. No public comments were received during the
public meeting.
RESPONSE TO COMMENTS
No public comments were received during the public comment period.
-------
LIST OF ACRONYMS
ACZA
ARARs
AWQC
ammonia, copper II oxide, zinc, and arsenic
Applicable or relevant and appropriate requirements
ambient water quality criterion
bgs
CAMU
CERCLA
COPC
CFS
cys
below ground surface
corrective action management unit
Comprehensive Environmental Response, Compensation, and Liability
Act
constituent of potential concern
cancer slope factor
cubic yards
DO
dissolved oxygen
EPC
ERB
ERT
ES
exposure point concentration
Emergency Removal Branch
Emergency Response Team
Enforcement Standard
FHHRA
FS
ft/day
ft/ft
ft/yr
FWS
GAC
gpm
HI
HQ
Focused Human Health Risk Assessment
Feasibility Study
feet per day
feet per feet
feet per year
U.S. /Fish and Wildlife Service
granular activated carbon
gallons per minute
hazard index
hazard quotient
IRIS
Ib/hr
L/kg
Integrated Risk Information System
pounds per hour
liters per kilogram
-------
LDR
LNAPL
LOAEL
land disposal restriction
light non-aqueous phase liquid
lowest observed adverse effect level
MCLG
MCLs
mg/kg
msl
MTRs
maximum contaminant level goal
maximum contaminant levels
milligram per kilogram
micrograms/liter
micrograms/kilogram
mean sea level
minimum technology requirements
NCP
NOAA
NOAFL
NPL
O&M
OSHA
PALs
PCP
ppb
pph
PRGs
PVC
PW?
National Contingency Plan
National Oceanic and Atmospheric Administration
no observed adverse effect level
National Priorities List
Operation and Maintenance
Occupational Safety and Health Administration
Preventative Action Limits
Pentachlorophenol
parts per billion
pounds per hour
Preliminary Remediation Goals
polyvinyl chloride
Penta Wood Products
RCL
RCRA
RiD
RJ
RME
ROD
residual contaminant level
Resource Conservation and Recovery Act
reference dose
remedial investigation
reasonable maximum exposure
Record of Decision
S.U.
SACM
standard units
Superfund Accelerated Cleanup Model
-------
SARA Superfund Amendments and Reauthoriztion Act
SDWA Safe Drinking Water Act
scfm standard cubic feet per minute
STP standard temperature and pressure
SVE soil vapor extraction
TBC to be considered
TCLP toxicity characteristic leaching procedure
TMV toxicity, mobility, and volume
TPH total petroleum hydrocarbons
TSD treatment, storage, or disposal
U.S. EPA United States Environmental Protection Agency
UCL upper confidence limit
YGCs volatile organic compounds
WDNR Wisconsin Department of Natural Resources
WPDES Wisconsin Pollutant Discharge Elimination System
-------
LIST OF REFERENCES
ASTDR (Agency for Toxic and Disease Registry). Toxicological Profiles for
Pentachlorophenol. U.S.Department of Health and Human Services. 1994.
Burnett County Plat Book. 1997. Wisconsin, 15th Edition.
CH2M HILL. February 1998a. Draft, Screening Level Ecological Risk Assessment, Penta
Wood Products, Town of Daniels, Wisconsin.
CH2M HILL. March 1998b. Draft, Remedial Investigation Report, Penta Wood Products,
Town of Daniels, Wisconsin.
CH2M HILL. May 1998c. Draft, Feasibility Study Report, Penta Wood Products, Town of
Daniels, Wisconsin.
Chiou, C.T., L.J. Peters, and V.H. Freed, 1979. A Physical Concept of Soil-Water Equilibria
for nonionic organic compounds. Science. 206:831-832.
Cjoi, J. And S. Aomine. 1993 Adsorption of pentachlorophenol by soils. Soil Science Plant
Nutrition. 20(2): 135-144.
Conestoga-Rovers and Associates. March 1992. Remedial Investigation and Corrective Action
Plan, Penta Wood Products Inc. Siren, Wisconsin.
Dragun, J. Et at. 1991. What do we really know about the fate and transport of diesel fuel in
soil systems? Hydrocarbon Contaminated Soils, Lewis Publishers, Chelsea, Michigan.
Dragun, J., et al. 1991. What do we really know about the fate and transport of diesel fuel in
soil systems? Hydrocarbon Contaminated Soils, Lewis Publishers, Chelsea, Michigan.
Ecology & Environment, Inc. August 1997. Final Focused Human Health Risk Assessment,
Penta Wood Products Site, Siren, Wisconsin, Work Assignment No. 43-5LWE
.Ecology & Environment, Inc. June 18, 1993. Site Assessment Report for Penta Wood
Products, Technical Directive Document T05-9301-004.
Eisler, R. "Pentachlorophenol Hazards to Fish, Wildlife, and Invertebrates: A Synoptic
Review. "U.S. fish and Wildlife Service Biological report. 85(1.17). 1998.
Farr, A.M., Houghtalen and McWhorter. !990. Volume Estimation of Light Nonaqueous
Phase Liquids in Porous Media. Vol.28, No. 1, Ground Water, January-February.
Hillel, D. 1982. Introduction to Soil Physics. Academic Press, New York, NY.Kirk-Othmer
-------
Encyclopedia of Chemical Technology. 3rd Edition. 1978-84.
Perlous Environmental &. Biotechnology Corporation. June 1997. Bioremedation of
Pentachlorophenol. Literature Survey of Metabolic pathways and Rate Constants, prepared for
Doug Kunkel. CH2MHH1. Washington.
Rochkind ML. et al. USEPA. Cincinnati. Ohio. Report No. EPA-600/2-86/090.
McLaren. R.G., and D.V. Crawford. 1973. The fraction of copper in soils. Journal of Soil
Science. 24(2): 172-181.
Pelorus Environmental & Biotechnology Corporation. June 1997. Bioremedation of
PentachloTOphenoL Literature Survey of Metabolic Pathways and Rate Constants, prepared for
Doug Kunkel. CH2M HILL. Washington.
Rochkind, M.L., et al. 1986. USEPA, Cincinnati, Ohio. Report No. EPA-600/2-86/090.
Roy F. Weston. December 1994. Draft Report-Preliminary Hydrogeologic Investigation, Penta
Wood Products Site. Daniels. Wisconsin.
Roy F. Wesion. May 1995. Final Report Site Characterization Extent of On- and Off-site
Contamination Surficial and Near Surface Soil. Penta Wood Products Site. Siren. Wisconsin.
Roy F. Weston. December 1994a. Final Report Phase I - Remedial Technology Evaluation,
Persia Wood Products, Siren, Wisconsin.
Roy F. Weston. May 1995 and December I995a. Bioremedation Activity Summary. Penta
Wood Products Site. Daniels, Wisconsin.
Shacklette and Boemgen. 1984. Element Concentrations in Soils and Other Surficial Materials
of the Conterminous United States. USGS Professional Paper 1270.
Shimizu. Y.S. and Y. Terashima. 1992 Sorption of anionic pentachlorophenol (PCP) in
aquatic environments: the effect of pH. Water Science Technology. 25(11 ):41-48.
Smith, M. H.. et al. 1994. Applied Environmental Microbiology. 60:4111.
USEPA. April 13,1998. Approach for Addressing Dioxin in Soil at CERCLA and RCRA Sites
Memorandum, prepared by Timothy Fields, Jr.. Acting Administrator, Office of Solid Waste
and Emergency Response. OSWER Directive 9200.4-26.
USEPA. January 1998a. Steam Injection for Soil and Aquifer Remediation, prepared by Eva
L. Davis. Offices of Research and Development and Solid Waste and Emergency Response.
EPA/540/S-97/505.
USEPA. 1998b. Integrated Risk Information System (IRIS).
USEPA. 1998c. Health Effects Assessment Summary Tables (HEAST).
-------
USEPA. June 1997. Risk Assessment Guidance for Superfund: Process for Designing and
Conducting Ecological Risk Assessments.USEPA. 1996. Drinking Water Regulations and
Health Advisories; February 1996.
USEPA. 1993 Wildlife Exposure Factors handbook, Volume I of II. EPA/600/R-93/187a.
U.S. EPA, 1991 a. "Risk Assessment Guidance for Superfund Volume I: Human Health
Evaluation Manual, Supplemental Guidance, Standard Default Exposure Factors; March 25,
1991.
U.S. EPA, 1990. "National Oil and Hazardous Substances Pollution Contingency Plan; Final
Rule", 55FR8666; March 8,1990.
U.S. EPA, 1989a. "Risk Assessment Guidance for Superfund: Volume I Human Health
Evaluation.
U.S. EPA, 1989b. A Risk Assessment Guidance for Superfund: Volume II Environmental
Evaluation Manual.
U.S. EPA. October 1998. Guidance for Conducting Remedial Investigations and Feasibility
Studies Under CERCLA, Interim Final. Office of Emergency and Remedial Response,
OSWER Directive 9355.3-01
USGS. 1982. Siren West, Wisconsin Quadrangle Map, SW/4 Webster 15', N4545-
W9222.5/7.5.Vesala, A., 1979. Pentachlorophenol. Solubility Data Series. 1985(20):6-14.
Wisconsin Department of Natural Resources. March 3,1998. Sediment Quality Objectives for
the Contaminants of Concern at the Penta Wood Products Superfund Site, Town Of Daniels
Memorandum, prepared by Tom Janisch, Water Programs.
Wisconsin Geological and Natural History Survey (WGNHS). 1990. "Soils, geologic and
hydrogeologic controls of water quality in Northwestern Wisconsin Lakes." WDNRBR,
WRRS, Fitchburg, WI.
59
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