United States
Environmental Proection
Agency
Share your opinions
EPA offers several ways for you to
participate in the cleanup process
at the Ashland/NSP Lakefront site.
Before the Agency holds the public
meeting and comment period,
EPA and WDNR invite you to an
information session on Wednesday,
June 17, 7:00 p.m. at the Northern
Great Lakes Visitor Center,
29270 County Highway G. At the
information session you can hear
about EPA's recommended cleanup
plan and other cleanup alternatives
that were considered and ask
questions.
The information session will be
followed by a public meeting and
comment period. By commenting on
the proposed plan your input helps
EPA determine the best course of
action. EPA will host a public meeting
on Monday, June 29, 7:00 p.m. at
the Northern Great Lakes Visitor
Center, where oral and written
statements will be accepted.
The public comment period runs
from June 17 - July 16. You can
submit comments on the cleanup plan:
• Via the Web at www.epa.gov/
regionS/publiccomment/ashland-
pubcomment.htm
• E-mail to Parti Krause at krause.
patricia@epa.gov
• Fax to Parti Krause at 312-697-
2568
• Fill out and mail the comment
form in this fact sheet
Based on public comments received
EPA could modify its recommended
cleanup plan or pick another
alternative altogether so your opinion
is important.
See backpage for contact information.
EPA Proposes Cleanup Plan
Ashland/Northern States Power Lakefront Superfund Site
Ashland, Wisconsin June 2009
U. S. Environmental Protection Agency is proposing a plan to clean up
contaminated soil, ground water and sediment at targeted areas of the
Ashland/NSP Lakefront site1. The areas are contaminated with waste tar and
spilled oil from a former manufactured gas plant and some contaminated
areas also contain wood debris left by a lumber mill. EPA is the lead agency
and the Wisconsin Department of Natural Resources is the support agency
for activities at the site.
EPA recommends digging up soil from the most contaminated areas of the
site, treating the soil with heat to remove contamination and re-using the soil
after treatment. EPA recommends using barriers to stop the movement of
ground water contaminants and possibly injecting a chemical into wells. In
the underlying aquifer, EPA recommends adding extraction wells to pump
and treat contaminated ground water. EPA recommends dry excavation and
removal of contaminated sediment in the inner bay area of Chequamegon
Bay and wet dredging in the off shore area.
EPA's cleanup goals for the site are to protect people's health and the
environment at risk by:
• Reducing or eliminating exposure to contaminants that pose an
unacceptable risk at the site;
• Removing contamination, treating contaminated materials, and
containing remaining contaminants to lessen effects of discharge to
the air, land, sediment, or water;
• Stopping or minimizing the movement of contaminants from the soil
to ground water or surrounding surface water; and
Ensuring future beneficial use of land at the site.
Public comment needed
The purpose of this proposed plan fact sheet is to give you background
information about the Ashland/NSP Lakefront site, describe the various
cleanup alternatives considered, and explain EPA's recommended cleanup
plan. You are encouraged to comment on this proposed plan. EPA will be
accepting comments from June 17 through July 16. See the box to the left for
ways to learn more and provide comments to EPA.
'Section 117 (a) of the Comprehensive Environmental Response, Compensation, and Liability
Act (CERCLA known as the Superfund law) requires publication of a notice and a proposed
plan for the site remediation. The proposed plan must also be made available to the public for
comment. This proposed plan fact sheet is a summary of more detailed information contained
in the remedial investigation, feasibility study, and other documents in the administrative
record for the Ashland/NSP Lakefront site. Please consult those documents for more detailed
information.
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Aerial photo shows the Ashland Lakefront site. The "Upper Bluff/Filled Ravine includes the location of the former manufactured gas
facility that created much of the pollution on the site.
EPA, in consultation with WDNR, will select a final
cleanup plan for the Ashland/NSP Lakefront site. This
will occur after review and consideration of information
given by the public during the 30-day public comment
period and at the public meeting. The final cleanup plan,
which will be announced in a local newspaper notice
and presented in an EPA document called a "record of
decision," could differ from the proposed plan depending
on information or comments EPA receives during the
public comment period.
Documents for review
You are also encouraged to review the supporting
documents for the Ashland site. The information includes
the complete proposed plan, the "remedial investigation"
and "feasibility study" reports and other documents (e.g.,
risk assessments). The remedial investigation is a study of
the nature and extent of contamination at the site, while
the feasibility study evaluates different cleanup options.
The risk assessments evaluate potential risks to people and
the environment from the contamination at the site. You
can review these and other supporting documents in the
information repositories listed on page 10 of this fact sheet
and online at www.epa.gov/region5/sites/ashland.
About the Ashland/NSP Lakefront site
The Ashland/NSP Lakefront site consists of properties
owned by Northern States Power Company of Wisconsin
(doing business as Xcel Energy) and Canadian National
Railroad, a portion of the city-owned Kreher Park and the
former wastewater treatment plant, sediment in an area
of Chequamegon Bay, Our Lady of the Lake church and
school, and private residences. Cleanup is focused on four
areas of the site:
Upper Bluff/Filled Ravine is the site of a former
manufactured gas plant. The plant produced "water gas"
for street and home lighting and other uses between 1885
and 1947. A ravine ran through the property, emptying
out at the former Lake Superior shoreline, near what is
now the Canadian National Railroad corridor (formerly
known as Wisconsin Central Limited). The ravine was
filled by the early 1900s. NSP-owned property in the
Upper Bluff/Filled Ravine area still contains remnants of
buildings and equipment from the plant and is now a NSP
service facility. The property overlooks Kreher Park and is
bounded by Lake Shore Drive, St. Claire Street, Prentice
Avenue, and 3rd Avenue. The railroad, church and school,
and private residences are also in the Upper Bluff/Filled
Ravine area, but are not the focus of the cleanup.
Kreher Park is located along the bay and includes the
area between the upper bluff and Chequamegon Bay. The
area did not exist before the late 1800s as the shoreline
was much closer to what is now the railroad corridor.
Kreher Park was created over the decades as various fill
materials were placed into the bay. The eastern portion was
filled with sawdust, wood waste and other material from
local sawmills, including the former Schroeder Lumber
Co. that operated until the 1930s. Solid waste, primarily
demolition debris, was disposed of along the western side
of the property in the 1940s. In 1942 the City of Ashland
took ownership of the property and the area was vegetated.
There may have been a ponded area of a black tarry
substance and a map of Kreher Park from 1953 indicated
that a "coal tar dump" was present during that time. Kreher
Park is mostly grass covered and a gravel overflow parking
area for the marina occupies the west end of the property.
The former City of Ashland wastewater treatment plant
and associated structures front the bay inlet on the north
side of the property.
Copper Falls aquifer is a thick water-bearing formation
composed of layers of sand and gravel that lies underneath
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the Upper Bluff/Filled Ravine and part of Kreher Park.
This aquifer is overlain by about 30 feet of clay/silt known
as the Miller Creek rock formation.
The Chequamegon Bay impacted area of the site is
roughly 16 acres between the boat marina and the Prentice
Avenue boat launch extending out about 300 feet from the
shoreline.
Waste, including tar and oil, moved from the gas plant to
the park and the bay through a ravine, and later through a
pipe buried inside the ravine. Later, after Kreher Park was
filled in, additional pipes and a ditch may have conveyed
waste to the bay. Other activities in the area, including
possible wood treatment at local sawmills and construction
in the 1950s of the former municipal wastewater treatment
plant, may have added to contamination.
Site pollution was discovered in 1989 when workers
encountered oil and tar in excavations to expand the
former wastewater treatment plant. The wastewater plant
was later closed when a new7 one was built in another
location.
During the 1990s both WDNR and NSP performed a series
of investigations to assess contamination at Kreher Park, at
the NSP property and in Chequamegon Bay.
In response to a citizen's petition and to address long-term
issues, EPA added the site to the National Priorities List
in 2002. The NPL is a roster of waste sites eligible for
cleanup under EPA's Superfund program. NSP signed an
agreement in 2003 to conduct the remedial investigation/
feasibility study.
so far
In 2000, NSP began pumping out ground water from the
Copper Falls aquifer as a pilot project. The pumped water
is treated at the NSP plant and discharged into the city's
sanitary sewer. So far, more than 1.7 million gallons of
contaminated water has been pumped out, yielding about
10,000 gallons of coal tar. Also, in 2002, NSP dug out
contaminated soil and waste at a seepage point at the base
of the bluff and removed much of the pipe in the ravine.
This area was then covered with clean material.
pollution
Contamination at the site was primarily generated by the
gas plant and has affected soil, ground water and sediment.
The most commonly occurring contaminants at the site are
as follows:
Carburated water gas tar/oil wastes/coal tar
Mixture of chemicals that make up part of the liquid waste
from the gas production process. This tarry/oily substance
is a mixture of hundreds of chemical compounds including
VOCs, SVOCs, and PAHs (listed below) and is found
throughout the site.
Volatile organic compounds and benzene
VOCs are organic chemicals that evaporate readily into the
atmosphere. VOCs are found in many things, from paints,
coatings, and glue to gasoline and diesel fuel. Hie most
common VOC at the Ashland site is benzene.
Semi-volatile organic compounds
SVOCs are organic compounds that evaporate at standard
temperatures over a longer period of time than VOCs. A
variety of SVOCs are used in building materials to provide
flexibility, water resistance or stain repellence as well as
fire rctardant.
Polyeydie or polynuclear aromatic hydrocarbons and
napthalene
PAHs are a group of over 100 different chemicals that
are formed during the incomplete burning of coal, oil and
gas and other organic substances. The most commonly
occurring PAH at the Ashland site is naphthalene.
Napthalene is strong smelling and is made from coal tar or
petroleum.
These contaminants are found in different forms as non-
aqueous phase liquid, also known as "free product."
NAPLs are underground pockets of tar and other materials
in liquid form that don't readily mix with water. There are
two kinds of NAPLs found at the site:
Floating
Light non-aqueous phase liquid contains lighter VOCs
that float on top of the water table. Most common
petroleum fuels and lubricating oils are LNAPLs.
Sinking
Dense non-aqueous phase liquid contains heavier
VOCs that sink through the water table. Typical
monitoring wells do not indicate their presence
because they sink to the bottom instead of floating on
top of the water table. PAHs such as napthalene are
DNAPLs.
Pollution found its way into soil, ground water and the bay,
and the underlying debris at Kreher Park. Test pits dug in
the park revealed an oily sheen running through the fill
material. When there are large waves on Lake Superior,
compounds are stirred up from the bay sediment and cause
oil slicks on the surface of the bay.
Summary of
EPA reviewed and approved a "human health risk
assessment" and a "baseline ecological risk assessment"
which identify how people and wildlife might be exposed
to contamination at the site. These risk assessments look at
what would happen if contamination is not cleaned up and
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there are no restrictions, fences, or signs to prevent people
from being exposed. While some potential exposures are
very unlikely, others are very possible or even known to
have occurred at the site.
The risk assessment determined that elevated health risks
do exist for three potential exposure paths:
• Cancer risk levels were above EPA limits if
new homes were built over the filled ravine and
potential residents were exposed to the soil.
This risk assessment is very conservative since
no homes sit there now and future residential
construction is unlikely. Non-cancer health risks
for a potential residential area were low.
• Construction workers digging holes and trenches
in Kreher Park could be exposed to unsafe
contamination levels but only at depths greater
than 4 feet. The study determined that workers
doing grading, road building, parking lot
construction and landscaping activities would not
be exposed to dangerous pollutant levels.
Non-cancer health risks also are present for
workers breathing contaminated indoor air in
the utility service center but only if they worked
in there full-time for 25 years. Currently, office
space in the service center is used only part-
time. Samples collected in the filled ravine area
indicated that below surface vapors are not moving
toward the residential area.
Sports fish from the site do not contain harmful levels of
site-related contamination, but recent testing of some smelt
at the site found unacceptable contaminant levels. People
should continue to follow the general Lake Superior fish
consumption advice available from the Ashland County
Health Department. Modeling in the risk assessment
suggested that oil slicks floating on surface water would
pose a health risk for people who swim or wade at the site,
but direct contact with sediment was not a health concern.
Wildlife was studied for pollution effects. Contamination
posed little direct risk to birds, mammals and fish although
occasionally contaminants are stirred up and cause
an oily slick on the surface of the bay where it could
potentially affect wildlife. The risk assessment did find that
contamination is harming the tiny organisms that live at
the bottom of the bay and form the base of the food chain.
Summary of cleanup alternatives
A number of different cleanup techniques for soil, ground
water, and sediment went through a complex screening
process explained in the feasibility study. These cleanup
alternatives were evaluated by each of the nine criteria
required by law (see box below). For a more complete
description of alternatives and comparison to other
Evaluation criteria
EPA uses nine criteria to compare cleanup alternatives:
Threshold criteria are requirements each alternative must meet in order to be eligible for selection.
1. Overall protection of human health and the environment addresses whether an alternative adequately protects both
human health and the environment. This standard can be met by reducing or removing pollution or by reducing exposure
to it.
2. Compliance with applicable or relevant and appropriate requirements (ARARs) assures that each project complies
with federal and state laws and regulations.
Balancing criteria are technical criteria with detailed analysis and are used to weigh major
trade-offs among alternatives.
3. Long-term effectiveness and permanence evaluates how well an alternative will work over the long-term, including
how safely remaining contaminants can be managed.
4. Reduction of toxicity, mobility or volume through treatment addresses how well the alternative reduces the toxicity
(the chemical makeup of a contaminant that makes it dangerous), movement and amount of pollution.
5. Short-term effectiveness compares how quickly an alternative can help the situation and how much risk exists while it's
being constructed.
6 Implementability evaluates how feasible the cleanup plan is and whether materials and services are available to carry
out the project.
7. Cost includes not only buildings, equipment, materials and labor but also the cost to put the plan in place and operate
and maintain it over time.
Modifying criteria can be fully considered only after public comment is received on the proposed plan.
8. State acceptance determines whether the state environmental agency, in this case WDNR, accepts the proposed cleanup
alternative. EPA evaluates this criterion after receiving public comments.
9. Community acceptance determines what nearby residents and other stakeholders think about the proposed cleanup
plan. EPA evaluates this standard after a public hearing and comment period.
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alternatives considered please consult the feasibility study
and the proposed plan.
Based on information currently available, the
recommended cleanup meets the threshold criteria and
gives the best balance of tradeoffs among the other
alternatives with respect to the balancing criteria.
Common for all
Several of the cleanup alternatives require institutional
controls (e.g., deed restrictions, land use controls such as
an easement or covenant) to limit the use of portions of the
property or ensure that the contaminated water is not used
for drinking water purposes. In addition, most alternatives
include long-term monitoring and maintenance on the
surface barriers and sediment cap to make sure remaining
buried pollution is not moving off-site.
S-1: No action. This alternative must be considered at
every Superfund site. It means leaving soil in place with
no engineering, maintenance or monitoring. Cost: $0
S-2: Containment using engineered surface barriers
This means covering an area with a barrier to stop rain
and snow melt from seeping through the contamination
and into the ground water and lake. This would also stop
wind from blowing contaminated soil and protects people
and animals from touching the soil. In areas of the Upper
Bluff/Filled Ravine and Kreher Park existing asphalt
pavement would be replaced and new7 asphalt pavement
installed. A solid cap would be placed over the former coal
tar dump area in Kreher Park. Surface barriers would be
periodically inspected and repaired or replaced as needed.
The amount of soil contained in the most contaminated
areas is about 39,800 cubic yards.
Estimated cost: $1.9 million
All the remaining soil cleanup alternatives are based on
either "limited" or "unlimited" removal.
Limited soil removal
Limited removal means digging up and removing
contaminated soil from the most contaminated areas in
the Upper Bluff/Filled Ravine area and Kreher Park.
The upper bluff requires removal of material from the
filled ravine. At Kreher Park removal of material is
required in the coal tar dump area. Limited removal
would involve demolishing the center section of the
NSP service center, removing asphalt pavement, and
digging up the former gas holders. Ground water
seeping into the excavated area would be collected,
placed in a holding tank and treated before discharge
to the sanitary sewer. After excavation these areas
of the site would be restored with clean fill material,
new asphalt pavement, and an existing street would
be upgraded. Heavy equipment such as backhoes,
bulldozers, and front-end loaders would be used for
digging. About 14.350 cubic yards of soil would be
removed during limited soil removal.
Unlimited soil removal
Unlimited removal means digging up all contaminated
areas of the Upper Bluff/Filled Ravine and Kreher
Park. At the upper bluff area this would require the
excavation of all fill material from the filled ravine,
demolishing the center section of the NSP service
center, removing asphalt pavement, and digging up
former gas holders. After excavation, areas of the
site would be restored with clean fill material and
new asphalt pavement and an existing street would
be upgraded. At Kreher Park small trees and bushes
would be cleared. Layers of wood waste and the fill
over the waste would be dug. Because digging would
be done below lake level a temporary sheet pile wall
would be constructed to allow for dry excavation.
Ground water that seeps into the excavated area would
be collected, placed in a holding tank and treated
before discharge to the sanitary sewer. About 259,600
cubic yards of soil would be removed.
S-3A: Limited removal and off-site disposal: This
alternative transports contaminated soil to an off-site
landfill or landfills for disposal.
Estimated cost: $4.9 million
S-3B: Unlimited removal and off-site disposal: Removal
of all fill material in Kreher Park may result in the
permanent loss of the current use of Kreher Park. After
digging, Kreher Park could be restored to a wetland area
or filled with clean material to restore it to its present
elevation. The contaminated soil would be disposed off-
site in a specially constructed facility.
Unlimited removal and off-site disposal and
backfill Kreher Park to its current elevation.
Estimated cost: $42.9 million
• Unlimited removal and off-site disposal and
restore Kreher Park as a wetland.
Estimated cost: $45.1 million
S-4A: Limited removal and on-site disposal: At Kreher
Park there is enough space for the construction of an on-
site disposal cell for the contaminated material removed
from the filled ravine and from Kreher Park's coal tar
dump area. A solid cap would be placed over the disposal
cell. The cost includes constructing the one-acre disposal
cell. Estimated cost: $3.8 million
S-4B: Unlimited removal and on-site disposal: At
Kreher Park there is enough space for the construction of
an on-site disposal cell for all the contaminated material
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Comparison of soil cleanup alternatives
Evaluation Criteria
Overall protection
of human health and
environment
Compliance with
ARARs
Long-term
effectiveness and
permanence
Reduction of toxicity,
mobility and volume
through treatment
Short-term
effectiveness
Implementability
Cost
State acceptance
Community
acceptance
No action
S-l
None
None
None
None
None
None
None
Containment
using
engineered
surface
barriers
S-2
L
L
L
L
H
H
L
Limited
removal
and off-site
disposal
S-3A
H
H
H
H
H
H
M
Unlimited
removal
and off-site
disposal
S-3B
H
H
H
H
H
M
H
Limited
removal
and on-site
disposal
S-4A
M
M
M
M
M
H
M
Unlimited
removal
and on-site
disposal
S-4B
H
M
M
M
M
H
M
Limited
removal
and on-site
thermal
treatment
S-5A
H
H
H
H
H
H
H
Limited
removal
and off-site
incineration
S-5B
H
H
H
H
H
M
H
Limited
removal and
on-site soil
washing
S-6
M
M
M
M
H
M
H
Will be evaluated after public comment
Will be evaluated after public comment
= EPA recommends this alternative
L= Low
M= Medium
removed from the filled ravine and contaminated soil from
Kreher Park. A solid cap would be placed over the disposal
cell. The cost includes constructing the four-acre disposal
cell at Kreher Park. Estimated cost: $6.4 million
S-5A: Limited removal and thermal treatment (EPA
recommends this alternative): Thermal treatment is a
way to remove contaminants from soil by heating it in an
on-site mobile unit. Wood waste and other debris would
be separated from the soil before treatment and the waste
and debris would be transported off-site for disposal.
The mobile unit for thermal treatment would be set up at
Kreher Park. Estimated cost: $6.8 million
S-5B: Limited removal and off-site incineration:
Contaminated soil suitable for incineration would
be transported off-site to a facility for treatment and
disposal. Wood waste and fly ash and cinders would be
separated from soil selected for incineration and would
be transported off-site for disposal. Fill material not
contaminated would be returned and used as backfill.
Estimated cost: $11.8 million
S-6: Limited removal and soil washing: Soil washing
mechanically scrubs dug up soil to remove contaminants.
The wastewater would be treated on-site before discharge.
A mobile unit would be used to wash the soil on-site.
Wood waste would be separated from the soil and
transported off-site for disposal. Estimated cost: $8.3
million
H = High
Ground water cleanup alternatives
GW-l: No action. This alternative must be considered
at every Superfund site. This would mean leaving
contaminated ground water in place with no engineering,
maintenance or monitoring. Cost: $0
GW-2A and 2B: Containment using engineered surface
and vertical barriers (EPA recommends this alternative)
This alternative would use man-made barriers to stop the
movement of contaminants and keep infiltrating water
from touching contaminated soil. At the Upper Bluff area
the filled ravine would be capped. Kreher Park could be
partially capped or entirely capped. (These are alternatives
GW-2A and GW-2B.) Surface barriers do not disturb
the contaminated area and only minimal maintenance is
required. Vertical barrier walls are slurry walls or sheet
piling that would be installed around the area of the
contaminated ground water. Contaminated material may be
disturbed during construction of vertical barrier walls and
long-term maintenance such as ground water extraction
may be required. Vertical barriers would not work for the
Copper Falls aquifer because this deep aquifer is confined
by the Miller Creek rock formation and installing barrier
walls could compromise the aquifer. Clearing trees and
digging a ground water diversion trench would be involved
in containment with surface and vertical barriers.
Long-term operation and maintenance of the containment
would include removing contaminated ground water with
added ground water extraction wells and annual inspection
of surface barriers. Contaminated ground water would be
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treated on-site before discharge. A cap for the entire Kreher
Park would result in significant disturbance and added
costs. Long-term operation, maintenance and monitoring
costs may be lower if capping the entire Kreher Park
reduces the volume of ground water extraction.
GW-2A: Containment for the filled ravine and partial
capping at Kreher Park. (EPA recommends this
alternative) Estimated cost: $9.2 million
GW-2B: Containment for the filled ravine and capping
the entire Kreher Park. Estimated cost: $10.9 million
A number of ground water cleanup methods were
evaluated. In general, installing wells to deliver treatment
may be difficult and effectiveness may be limited in areas
of shallow ground water where there are buried structures
and debris such as wood waste, bricks, and cinders. Some
treatment would not work for the Copper Falls aquifer
because this deep aquifer is confined by the Miller Creek
rock formation and installing certain treatment wells may
compromise the confinement. Alternatives GW-3 through
GW-8 are ground water treatment alternatives.
GW-3: In-place treatment using ozone sparge: This
treatment injects ozone into the ground through wells to
clean up ground water contamination. Ozone sparging can
be used at the Upper Bluff/Filled Ravine, at Kreher Park
and in the underlying Copper Falls aquifer.
Estimated cost: $3.5 million
GW-4: In-place treatment using surfactant injection
and removal using dual phase recovery: Wells would
be installed below the Miller Creek rock formation at the
Copper Falls aquifer. A "wetting agent" would be injected
to lessen the tension between NAPLs and water. Site
conditions at the Upper Bluff/Filled Ravine and Kreher
Park areas would limit effectiveness of this alternative.
Estimated cost: $1.4 million
GW-5: In-place treatment using permeable reactive
barrier walls: Permeable reactive barrier walls (walls with
holes to allow ground water flow) would be built below
ground to clean up ground water at the Upper Bluff/Filled
Ravine and Kreher Park. Estimated cost: $6.2 million
GW-6: In-place treatment using chemical oxidation
(EPA recommends this alternative): Chemicals would be
injected into wells to break up pollution in ground water.
Hydrogen peroxide is an oxidant that is commonly used
to break up contaminants in ground water and this method
was used in a demonstration at this site. Hundreds of holes
would be drilled in the filled ravine and at Kreher Park and
injected with the chemical. Estimated cost: $10 million
GW-7: In-place treatment using electrical resistance
heating: This treatment delivers electric current
underground to convert ground water and water in soil to
steam and to evaporate contaminants.
Estimated cost: $16 million
Comparison of ground water cleanup alternatives
Evaluation
Criteria
Overall protection
of human health
and environment
Compliance with
ARARs
Long-term
effectiveness and
permanence
Reduction of
toxicity, mobility
and volume
through treatment
Short-term
effectiveness
Implementability
Cost
State acceptance
Community
acceptance
No
action
GW-1
None
None
None
None
None
None
None
Containment
using
engineered
surface
barriers
GW-2A, 2B
M
H
L
M
H
H
H
Treatment
- ozone
sparge
GW-3
M
H
H
L
H
H
L
Treatment -
wetting agent
(surfactant
injection)
GW-4
H
H
H
M
H
H
L
Treatment
PRBs
GW-5
M
H
L
M
H
H
H
Treatment
chemical
oxidation
GW-6
H
H
H
H
H
H
H
Treatment
electrical
resistance
heating
GW-7
H
H
H
H
H
H
H
Treatment
steam
injection
GW-8
H
H
H
H
H
H
H
Ground
water
extraction
GW-9A
M
H
M
M
H
H
L
Enhanced
ground
water
extraction
GW-9B
M
H
M
M
H
H
L
Will be evaluated after public comment
Will be evaluated after public comment
= EPA recommends this alternative
L= Low
M= Medium
H = High
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GW-8: In-place treatment using steam injection: Steam
injection forces steam underground through wells drilled in
contaminated areas. Estimated cost: $12.5 million
Ground water extraction and treatment
Also called pump and treat, extraction wells with pumps
pull contaminated ground water to surface holding tanks
and then into treatment systems. Ground water extraction
wells can be used for both shallow and deep ground water.
Enhanced ground water extraction would install additional
extraction wells in the Copper Falls aquifer to increase
DNAPL removal and include continued operation of the
existing wells. Ground water extraction requires installing
an on-site treatment system to operate for an extended
period of time. Alternatives GW-9A and GW-9B are
extraction and treatment alternatives.
GW-9A: Existing ground water extraction system: The
existing ground water extraction system extracts ground
water from one well at the mouth of the filled ravine and
DNAPL from wells installed in the underlying Copper
Falls aquifer. Contaminated ground water is placed in a
holding tank and then treated. Estimated cost: $3 million
GW-9B: Enhanced ground water extraction systems
(EPA recommends this alternative for the Copper Falls
aquifer): Same as GW-9A with wells added in the Copper
Falls aquifer. Because ground water extraction can be a
relatively slow process adding more wells would speed the
ongoing ground water cleanup. Estimated costs: Upper
Bluff/Filled Ravine - $164,000, Kreher Park - $18.9
million, and Copper Falls aquifer- $6.4 million
Sediment cleanup alternatives
The goal for sediment is to clean up areas in Chequamegon
Bay with contaminant levels greater than 9.5 parts per
Comparison of sediment cleanup alternatives
million PAH in sediment. A part per million or ppm is a
tiny measurement equal to one second in 12 days and is
commonly used to express a chemical concentration where
even small amounts can be hazardous.
In designing a dredging project a number of factors must
be considered, including physical obstructions, site access,
staging areas, potential release of contaminants during
dredging, and community disturbance. Kreher Park would
be used as a staging area for sediment removal activities
including storing, stabilizing and treating dredged material.
Precautions would be taken such as paving the marina
parking lot to make sure contaminated sediment does not
affect the soil underneath the staging area. Wood debris
removed would be disposed or treated separately. Water
would be drained from the sediment and the resulting
wastewater would be treated and discharged into the lake.
Removing water from sediment is called "dewatering."
Dry excavation or "dry dredge" would involve building
a wall off the shoreline, pumping out water and letting
the bay bottom and shoreline dry before removing all
contaminated sediment.
Sed-1: No action. This alternative must be considered
at every Superfund site. It means leaving the sediment in
place with no engineering, maintenance, or monitoring.
Cost: $0
Sed-2: Sediment containment within a confined
disposal facility, dredging, and monitoring: A confined
disposal facility is an enclosure where contaminated
sediment is placed and then capped with clean soil. The
CDF would be constructed over about seven acres of lake
bed and 13 acres of Kreher Park. Sheet piling would be
used to enclose the CDF. The CDF would contain all of the
contaminated sediment and soil. Sediment outside the area
Evaluation Criteria
Overall protection
of human health and
environment
Compliance with ARARs
Long-term effectiveness
and permanence
Reduction of toxicity,
mobility and volume
through treatment
Short-term effectiveness
Implementability
Cost
State acceptance
Community acceptance
No action
Sed-1
None
None
None
None
None
None
None
Consolidation,
confined disposal
facility and
monitoring
Sed-2
H
L
M
M
M
M
H
Removal, capping,
treatment and
disposal and
monitoring
Sed-3
H
M
M
M
M
H
H
Dredging,
treatment, and/
or disposal and
monitoring
Sed-4
H
H
H
H
L
H
H
Dry excavation,
treatment and/
or disposal and
monitoring
Sed-5
H
H
H
H
L
H
H
Dry excavation,
dredging, treatment
and/or disposal and
monitoring
Sed-6
H
H
H
H
L
H
H
Will be evaluated after public comment
Will be evaluated after public comment
= EPA recommends this alternative
L= Low
M= Medium
H = High
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of the CDF with levels of PAH above 9.5 ppm would be
dredged and placed in the CDF.
Estimated cost: $35 million.
Sed-3: Dredging, capping, treatment and/or disposal,
and monitoring: Dredge about four feet of wood debris
and sediment with PAH greater than 9.5 ppm before
capping with 6 inches of clean material. Dcwater and
stabilize the sediment, and either dispose off-site or reuse
after thermal treatment. Sediment areas outside the cap
would be monitored. Estimated cost range without and
with treatment: $37.1 - $47.8 million
Sed-4: Dredging, treatment, and/or disposal, and
monitoring: Dredge all sediment with PAH greater than
9.5 ppm. dewater, and then either thermally treat on-site at
Kreher Park for reuse after treatment or dispose off-site.
After dredging, place a 6-inch cap of clean material over
the work area. Under this alternative the greatest amount
of sediment would be removed, treated and disposed off-
site. Estimated cost range without and with treatment:
$49.9 - $67.7 million
Sed-5: Dry excavation, treatment and/or disposal,
and monitoring: Dry excavation in the Chequamegon
Bay would involve building a sheet pile wall off the
Kreher Park shoreline, pumping out water and letting
the bay bottom and shoreline dry before removing all
contaminated sediment over 9.5 ppm. Dewater and
stabilize sediment and dispose sediment at a permitted
landfill. Estimated cost range without and with
treatment: $78.9 - $91.8 million
Sed-6: Dry excavation (inner bay) and dredging (outer
bay), treatment and/or disposal, and monitoring (EPA
recommends this alternative): Use dry excavation near
shore for wood waste and contaminated sediment and
dredging offshore for contaminated sediment with PAH
greater than 9.5 ppm. Cap offshore area with 6 inches of
clean material, dewater sediment and stabilize at Kreher
Park and either dispose off-site or reuse after treatment.
Estimated cost range without and with treatment:
$68.5 - $80.4 million
Evaluation of
Each of the soil, ground water and sediment cleanup
alternatives was evaluated against the first seven of the
nine criteria set by Superfund law (see criteria explanation
in the box on page 4). EPA picked its recommended
alternatives based on the following justifications. State
and community acceptance will be evaluated after EPA
receives public comments.
Soil
EPA believes that limited removal and thermal treatment
(S-5A) will achieve the best balance among the nine
criteria because a significant mass of contaminated soil
will be removed. EPA recommends treating contaminated
soil after removal. If this is not cost-effective, then
off-site disposal is recommended. This alternative will
significantly reduce exposure to soil contamination by-
people and wildlife, will comply with federal and state
regulations, and is a cost-effective way to manage the
most contaminated material. The "'no action"' option would
not protect human health and the environment. Although
unlimited removal and off-site disposal would provide a
high level of human health and environmental protection,
limited removal would also provide a high level of
protection. Containment of contaminated materials and on-
site disposal of contaminated material would limit access
to people and wildlife and would result in reduced risk.
However, the overall level of protection in containment
and on-site disposal is lower because there is no reduction
of contaminant mass and contaminants will remain on site.
Ground water
EPA proposes using engineered surface and vertical
barriers with ground water extraction for the shallow
ground water in Kreher Park and the Upper Bluff/
Filled Ravine (GW-2A). For the Copper Falls aquifer,
enhanced ground water extraction is recommended
(GW-9B). In addition, in-place treatment (GW-6) can
be used to possibly enhance ground water cleanup since
treatment results in the removal of a significant amount
of contamination. EPA believes using containment with
surface and vertical barriers, ground water extraction,
and possible in-place treatment will achieve the best
balance among the nine criteria. The actual length of time
necessary to operate extraction and treatment systems will
be determined by considering the progress of the system
during the cleanup period. The "no action" alternative
would not protect human health and the environment.
Sediment
EPA proposes that the best way to handle the ncar-
shore contaminated sediment and wood debris would be
dry removal, with dredging of off-shore contaminated
sediment and wood debris (Sed-6). Dry dredging would
address concerns over the possible release of free product
in the wood waste and sediment into the water of the
bay which could potentially re-contaminate areas that
had been cleaned up. In addition, before any sediment
removal is conducted, controls would be put in place to
make sure that sediment would not be re-contaminated.
EPA recommends treating contaminated sediment after
removal. If this is not cost-effective, then off-site disposal
is recommended. The combination of dry removal and
dredging and treatment is protective of human health and
the environment because it results in the decontamination
of sediment and removes it from the environment. If
the sediment were to be sent to a landfill for disposal
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without treatment it would still be contaminated though
there would be no exposure to people or wildlife. Dry
excavation, dredging and treatment and/or disposal comply
with federal and state regulations and provide the highest
level of effectiveness over the long term. Containment
of contaminated materials and on-site disposal of
contaminated material would make the contaminated areas
inaccessible to people and wildlife and would result in
reduced risk. However, the overall level of protection in
containment and on-site disposal is lower because there is
no reduction of contaminant mass and contaminants will
remain on site. The "no action" alternative offers the least
protection and is not in compliance with federal and state
regulations.
Cleanup alternative scenarios
To organize all of these cleanup alternatives for
soil, ground water and sediment and the numerous
combinations, the feasibility study formed 10 cleanup
"scenarios." This fact sheet will reference the scenarios as
1 through 10 and the scenarios are summarized in the chart
on page 11.
Summary of the recommended scenario
EPA concluded the "no action" scenario would not
protect people or the environment and eliminated it from
consideration. EPA recommends Scenario 10
• Sediment cleanup in Chequamegon Bay would
be a combination of dry removal (inner bay) and
dredging (outer bay) with thermal treatment and/or
disposal of removed sediment and wood waste.
• Soil cleanup at Kreher Park and the Upper Bluff/
Filled Ravine would be limited soil removal with
thermal treatment or off-site disposal.
• Ground water clean up for shallow ground water
at the Upper Bluff/Filled Ravine and Kreher
Park would be engineered surface and vertical
barriers with ground water extraction. Ground
water cleanup at the Copper Falls aquifer would
be enhanced ground water extraction. Also
recommended is using in-place treatment to
possibly enhance ground water treatment and
extraction. Ground water cleanup and monitoring
will continue for a longer period of time.
Scenario 10 is recommended because it will achieve
substantial risk reduction by treating the contaminants
(free product) that are the principal threat at the site
and safely managing the remaining material. If thermal
treatment is not feasible based on pre-design studies or
the cost is significantly higher, the contaminated soil and
sediment would be disposed off-site. This combination
reduces risk sooner and costs are less than some of the
other scenarios. All of the scenarios, except Scenario 1
(no action), will take several years to complete.
Next steps
Before making its final decision, EPA will review
statements received during the public comment period and
at the public meeting. Based on new information presented
in the comments, EPA, in consultation with WDNR,
may modify its proposed plan or select another scenario
outlined in the plan. EPA encourages the public to review
and comment on the proposed cleanup plan. Much more
detail on the cleanup alternatives and scenarios is available
in the official documents on file at the information
repositories or EPA's Web site: www.epa.gov/region5/sites/
ashland. EPA will respond to the comments in a document
called a "responsiveness summary." This will be part of
the record of decision that describes the final cleanup plan.
The Agency will announce its decision on a cleanup plan
in a local newspaper and will place a copy of the record of
decision in the repositories and on the Web site.
For more information:
The remedial investigation and feasibility study and
other documents are available on EPA and WDNR
Web sites and at information repositories:
www.epa.gov/region5/sites/ashland
www.dnr.state.wi.us/org/aw/rr/cleanup/
ashland.html
Vaughn Public Library
502 W. Main St.
Ashland
Bad River Public Library
72682 Maple St.
Odanah
WDNR Spooner Service Center
810W. Maple St.
Spooner
Red Cliff
Environmental Protection Agency Office
37295 Community Road
Bayfield
10
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Cost
Scenario 1 Under this option no cleanup work would be performed and all $0
contamination would be left in place.
Sediment No action (Sed-1)
So/7 No action (S-1)
Ground wafer No action (GW-1)
Scenario 2 This is the least expensive scenario. $39.9 million
Sediment Dredging up to four feet, treatment and/or disposal, and monitoring (Sed-3)
So/7 Containment using engineered surface barriers- caps (S-2)
Ground water Operate existing ground water extraction system (GW-9A)
12345
O O O O O
o • o o o •
Scenario 3
Sediment
Soil
Ground water
Scenario 4
Sediment
Soil
Ground water
Scenario 5
Sediment
Soil
Ground water
Scenario 6
Sediment
Soil
Ground water
Estimated costs are dominated by sediment removal and enhanced $89.2 - $104.4 million • • • O O
ground water treatment.
Dredging, treatment and/or disposal, and monitoring (Sed-4)
Limited removal, off-site disposal, off-site incineration, on-site treatment (S-3A, S-5A, S-5B)
On-site treatment, enhanced ground water extraction (GW-3, 4, 6, 7,
GW-9B)
Sediment
So/7
Ground water
$74.9-$88.9 million
• • • O O •
Estimated costs are dominated by sediment removal.
Dredging, treatment and/or disposal, and monitoring (Sed-4)
Limited removal, off-site disposal, off-site incineration, on-site treatment (S-3A,S-5A, S-5B)
Containment using engineered surface barriers, vertical barriers, partial caps, on-site treatment (GW-2A, GW-3, 4, 5, 6,
7)
Estimated costs are dominated by construction of the disposal $38.5 - $45.9 million O O O O O O
facility.
Consolidation, Confined Disposal Facility , and monitoring (Sed-2)
Limited removal, on-site disposal (S-4A)
Containment using engineered surface barriers and capping entire Kreher Park, on-site treatment, enhanced ground
water extraction, (GW-2B,GW-3, 4, 6, 7,8, GW-9B )
$86-$103.6 mil
Estimated costs are dominated by sediment removal.
Dry excavation , treatment and/or disposal, and monitoring (Sed-5)
Limited removal, off-site disposal, off-site incineration, on-site treatment (S-3A,S-5A, S-5B)
Containment using engineered surface barriers and partial caps, or capping partial or entire Kreher Park,on-site
treatment, operate existing ground water extraction system, (GW-2A or 2B, GW-3 through 8, GW-9A)
Estimated costs are dominated by sediment removal.
$85.6-$108.1 million • • • O O •
Dry excavation, treatment and/or disposal, and monitoring (Sed-5)
Limited soil removal, off-site disposal, off-site incineration, on-site treatment (S-3A, S-5A, S-5B)
On-site treatment, enhanced ground water extraction, ( GW-3, 6, 7,8,
GW-9B)
$69.2-$90.4 million • • • O O •
Scenario 8 Estimated costs are dominated by sediment removal.
Sediment Dredging, treatment and/or disposal, and monitoring (Sed-4)
So/7 Limited removal, off-site disposal, off-site incineration, on-site treatment (S-3A, S-5A, S-5B)
Ground water Containment using engineered surface barriers and partial caps or capping entire Kreher Park, on-site treatment,
enhanced ground water extraction, , (GW-2A or GW-2B, GW-3, 5, 6, 7, 8, GW-9B)
Scenario 9 Removing all material from Kreher Park dominates the cost for this $123.2 million • • • O O
most expensive scenario
Sediment Dry excavation, treatment and/or disposal, and monitoring (Sed-5)
So/7 Unlimited soil removal, off-site disposal (S-3B)
Ground water Enhanced ground water extraction (GW-9B)
"Scenario 10 EPA's recommended alternative. Estimated costs are dominated by $83.4 - $97.5 million • • • O O
sediment removal.
Sediment Combination of dry excavation and dredging, treatment and/or disposal, and monitoring (Sed-6)
So/7 Limited soil removal, off-site disposal, off-site incineration, on-site treatment (S-5A recommended)
Ground water Enhanced ground water extraction, containment using surface and vertical barriers and partial caps, on-site treatment.
(GW-2A, GW-6, GW-9B)
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Contact EPA
For more information about the meeting or
special accommodations:
Patti Krause
EPA Community Involvement Coordinator
77 W. Jackson Blvd. (SI-7J)
Chicago, IL 60604
krause .patricia@epa. gov
800-621 -8431, ext. 69506
8:30 a.m. - 4:30 p.m., weekdays
For information about the meeting
or other questions:
John Robinson
WDNR, Northern Region Team Supervisor
107 Sutliff Ave.
Rhinelander, WI 54501
j ohn. robinson@wisconsin.gov
715-365-8976
For questions about the site
or technical information:
Jamie Dunn
WDNR, Project Manager
810 W. Maple St.
Spooner, WI 54801
j ames .dunn@wisconsin. gov
715-635-4049
For questions about the proposed plan or
technical information:
Scott Hansen
EPA Remedial Project Manager
77 W. Jackson Blvd. (SR-6J)
Chicago, IL 60604
hansen. scott@epa. gov
800-621-8431, ext. 61999
8:30 a.m. - 4:30 p.m., weekdays
For public health
and fish advisory information:
Henry Nehls-Lowe
Wisconsin Department of Health
1 W. Wilson St.
Madison, WI 53702
henry.nehlslowe@dhs.wisconsin.gov
608-266-3479
v>EPA
United States
Environmental Protection
Agency
Region 5
Superfund Division (SI-7J)
77 W. Jackson Blvd.
Chicago, IL 60604-3590
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ASHLAND/NORTHERN STATES POWER LAKEFRONT SITE
EPA Proposes Cleanup Plan
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