vvEPA
United States
Environmental Protection
Agency
Solid Waste And
Emergency Response
(5201 G)
EPA/540/R-95/076
PB95-962908
9200.5-707C
May 1995
SUPERFUND:
Progress at
National
Priority
List Sites
COLORADO
1995 UPDATE
Printed on Recycled Paper
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How to Use the NPL Book
The site fact sheets presented in this book
are comprehensive summaries that cover a
broad range of information. The fact sheets
describe hazardous waste sites on the NPL and
their locations, as well as the conditions
leading to their listing ("Site Description").
The summaries list the types of contaminants
that have been discovered and related threats
to public and ecological health ("Threats and
Contaminants"). "Cleanup Approach" pres-
ents an overview of the cleanup activities
completed, underway, or planned. The fact
sheets conclude with a brief synopsis of how
much progress has been made in protecting
public health and the environment. The
summaries also pinpoint other actions, such as
legal efforts to involve polluters responsible
for site contamination and community con-
cerns.
The fact sheets are arranged in alphabetical
order by site name. Because site cleanup is a
dynamic and gradual process, all site informa-
tion is accurate as of the date shown on the
bottom of each page. Progress is always being
made at NPL sites, and the EPA periodically
will update the site fact sheets to reflect recent
actions. The following two pages show a
generic fact sheet and briefly describe the
information under each section.
How Can You Use
This State Book?
You can use this book to keep informed
about the sites that concern you, particu-
larly ones close to home. The EPA is commit-
ted to involving the public in the decision
making process associated with hazardous
waste cleanup. The Agency solicits input from
area residents in communities affected by
Superfund sites. Citizens are likely to be
affected not only by hazardous site conditions,
but also by the remedies that combat them.
Site cleanups take many forms and can affect
communities in different ways. Local traffic
may be rerouted, residents may be relocated,
temporary water supplies may be necessary.
Definitive information on a site can help
citizens sift through alternatives and make
decisions. To make good choices, you must
know what the threats are and how the EPA
intends to clean up the site. You must under-
stand the cleanup alternatives being proposed
for site cleanup and how residents may be
affected by each one. You also need to have
some idea of how your community intends to
use the site in the future, and you need to know
what the community can realistically expect
once the cleanup is complete.
The EPA wants to develop cleanup methods
that meet community needs, but the Agency
only can take local concerns into account if it
understands what they are. Information must
travel both ways in order for cleanups to be
effective and satisfactory. Please take this
opportunity to learn more, become involved,
and assure that hazardous waste cleanup at
"your" site considers your community's
concerns.
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NPL LISTING HISTORY
Provides the dates when the
site was Proposed, made Final,
and Deleted from the NPL.
SITE RESPONSIBILITY
Identifies the Federal, State,
and/or potentially responsible
parties taking responsibility
for cleanup actions at the site.
ENVIRONMENTAL
PROGRESS
Summarizes the actions to
reduce the threats to nearby
residents and the surrounding
environment and the progress
towards cleaning up the site.
SITE NAME
STATE
EPA ID* ABCOOOOOOO
Site Description
EPA REGION XX
COUNTY NAME
LOCATION
Other Names:
1
: xxx xxxxx xxxxxxxxxxxx xxxxxx xxxxxxxxx xxxxxxxx xxxxxxxxxxxxx :
; xxxxxxxxxx xxxx xxxxxxxx xxxx xx xxxxxxxxx xx xxxxxx xxxxxxxx \
: xxx xxxxxxxxxxxxx xx xxxxxx xxxx xxxxx xxxx x xxx :
XXXXXXX XXX XXXjQOfcJtXXXXX XXXXX XXXXXX XXXXXXXX XXXXXXXX XXXX XXXXXXXXXX :
XXXXXXXXXXXX II II II II II II II INl"! IHU^^X XXX XX XXXXXXXXX XXXXX XXXX XXXX XXXXX XXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXXX XXXX II II llilltllllll||ll II II II XXXXXXXX XXXXX XXXX XXXXX XXX XXX XXXXXX
XXXXXXXXXXXX XX XXXXXXX XXX II II II II II IMlTlBI_||JI II XXXXXX XX XXXX XXX XXXXX XXX XXXXX XXX XXXXX
Site Responsibility:
xxxxxx xxx :
xxxxxx xxxxxxxxx xxxxxxxx
xxxxxxxxxxxxx xxxxxxxxx
NPL Listing History
xx/xx/xx
Final: XX/XX/XX
Threats and Contaminants
XXXXXX XXX XXXXX XXXXXXXXXXXX XXXXXX XXXXXXXXX XXXXXXXX
XXXXXXXXX XXXXXXXXXXXXX XXXXXXXXXX XXXX XXXXXXXX XXXX XX
XXXXXXXX XXX XXXXXXXXXXXX XXXXX XXX XXXXXXXXXXXXX XX XXXXXX XXXX
XXX XXXXXXXXXX XXXXXXXX XXXXXXX XXX XXXXXX XXXXXX XXXXX XXXXXX
XXXXXXXX XXXX XXXXXXXXXX XXXXXXXX XXXXXXXXXXXX XXXXXXXXX XXXX X XXX XX XXXXXXXXX'
XXXX XXXX XXXXX XXXXXXX XXXXXXXX XXXXXXXX XXXXXXXXX XXXX XXXX XXXXX XXXX
Cleanup Approach
XXXXXX XXX XXXXX XXXXXXXXXXXX XXXXXX XXXXXXXXX XXXXXXXX XXXXXXXXXXXXX
XXXXXXXXXXXXX XXXXXXXXXX XXXX XXXXXXXX XXXX XX XXXXXXXXX XX XXXXXX XXXXXXXX
XXXXXXXXXXXX XXXXX XXX XXXXXXXXXXXXX XX XXXXXX XXXX XXXXX XXXX X XXX XXXXXXXX
Response Action Status
XXXXXX XXX XXXXX XXXXXXXXXXXX XXXXXX XXXXXXXXX XXXXXXXX
XXXXXXXXXXXXX XXXXXXXXXX XXXX XXXXXXXX XXXX XX XXXXXXXXX XX
XXXXXXXXXXXX XXXXX XXX XXXXXXXXXXXXX XX XXXXXX XXXX XXXXX XXXX X
XXXXXXXX XXXXXXX XXX XXXXXX XXXXXX XXXXX XXXXXX XXXXXXXX XXXXXXX
XXXXXXXXXX XXXXXXXX XXXXXXXXXXXX XXXXXXXXX XXXX X XXX XX XXXXXXXXX XXXXX XXXX XXXX XXXXX
XXXXXXX XXXXXXXX XXXXXXXX XXXXXXXXX XXXX XXXX XXXXX XXXX XXXXXXXX XXXXX XXXX XXXXX XXX
XXX XXXXXX XXXXXXXXXXXX XX XXXXXXX XXX XXXXXX XX XXXXXX XXXXXXXX XXX :
Site Facts:
XXXXXX XXX XXXXX XXXXXXXXXXXX XXXXXX XXXXXXXXX
XXXXXXXXX XXXXXXXXXXXXX XXXXXXXXXX XXXX XXXXXXXX XXXX XX XXXXXXXXX XX
XXXXXXXXXXXX XXXXX XXX XXXXXXXXXXXXX XX XXXXXX XXXX XXXXX XXXX X XXX
; xxx xxxxxx
Environmental Progress
XXXXXX XXX XXXXX XXXXXXXXXXXX XXXXXX XXXXXXXXX XXXXXXXX XXXXXXXXXXXXX XXXXXXXXX
XXXXXXXXXXXXX XXXXXXXXXX XXXX XXXXXXXX XXXX XX XXXXXXXXX XX XXXXXX XXXXXXXX XXX
XXXXXXXXXXXX XXXXX XXX XXXXXXXXXXXXX XX XXXXXX XXXX XXXXX XXXX X XXX XXXXXXXXXX
XXXXXXXX XXXXXXX XXX XXXXXX XXXXXX XXX XXXXX XXXXXXXXXXXX XXXXXX XXXXXXXXX XXXXXXXX
Site Repository
XXXXXX XXX XXXXX XXXXXXXXXXXX XXXXXX XXXXXXXXX XXXXXXXX XXXXXXXXXXXXX XXXXXXXXX
SITE REPOSITORY
Lists the location of the primary site repository. The site
repository may include community relations plans, public
meeting announcements and minutes, fact sheets, press
releases, and other site-related documents.
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SITE DESCRIPTION
This section describes the location and history of the site. It includes descrip-
tions of the most recent activities and past actions at the site that have con-
tributed to the contamination. Population estimates, land usages, and nearby
resources give readers background on the local setting surrounding the site.
THREATS AND CONTAMINANTS
The major chemical categories of site contamination are noted, as well as
which environmental resources are affected. Icons representing each of the
affected resources (may include air, groundwater, surface water, soil, and
contamination to environmentally sensitive areas) are included in the margins
of this section. Potential threats to residents and the surrounding environ-
ments arising from the site contamination also are described.
CLEANUP APPROACH
This section contains a brief overview of how the site is being cleaned up.
RESPONSE ACTION STATUS
Specific actions that have been accomplished or will be undertaken to clean
up the site are described here. Cleanup activities at NPL sites are divided
into separate phases, depending on the complexity and required actions at the
site. Two major types of cleanup activities often are described: initial,
immediate, or emergency actions to quickly remove or reduce imminent
threats to the community and surrounding areas; and long-term remedial
phases directed at final cleanup at the site. Each stage of the cleanup strategy
is presented in this section of the summary. Icons representing the stage of
the cleanup process (initial actions, site investigations, EPA selection of the
cleanup remedy, engineering design phase, cleanup activities underway, and
completed cleanup) are located in the margin next to each activity descrip-
tion.
SITE FACTS
Additional information on activities and events at the site are included in this
section. Often details on legal or administrative actions taken by the EPA to
achieve site cleanup or other facts pertaining to community involvement with
the site cleanup process are reported here.
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Guide to the NPL Book Icons
The "icons," or symbols; accompanying the text allow the reader to see at a glance which envi-
ronmental resources are affected and the status of cleanup activities at the site.
Icons in the Threats
and Contaminants
Section
Icons in the Response
Action Status Section
Contaminated Groundwater re-
sources in the vicinity or underlying
the site. (Groundwater is often used
as a drinking water source.)
Contaminated Surface Water and
Sediments on or near the site.
(These include lakes, ponds,
streams, and rivers.)
Contaminated Air in the vicinity of
the site. (Air pollution usually is
periodic and involves contaminated
dust particles or hazardous gas
emissions.)
Contaminated Soil and Sludges on
or near the site. (This contamination
category may include bulk or other
surface hazardous wastes found on
the site.)
Threatened or contaminated Envi-
ronmentally Sensitive Areas in the
vicinity of the site. (Examples
include wetlands and coastal areas
or critical habitats.)
Initial, Immediate, or Emergency
Actions have been taken or are
underway to eliminate immediate
threats at the site.
Site Studies at the site to determine
the nature and extent of contamina-
tion are planned or underway.
Remedy Selected indicates that site
investigations have been concluded,
and the EPA has selected a final
cleanup remedy for the site or part
of the site.
Remedy Design means that engi-
neers are preparing specifications
and drawings for the selected
cleanup technologies.
Cleanup Ongoing indicates that the
selected cleanup remedies for the
contaminated site, or part of the site,
currently are underway.
Cleanup Complete shows that all
cleanup goals have been achieved
for the contaminated site or part of
the site.
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EPA ID
Number Site Name
CO7570090038 AIR FORCE PLANT PJKS
COD007063530 ASARCO, INC. (GLOBE PLANT)
COD000110254 BRODERICK WOOD PRODUCTS
COD980717938 CALIFORNIA GULCH
COD980717557 CENTRAL CITY-CLEAR CREEK
COD007431620 CHEMICAL SALES CO.
COD980716955 DENVER RADIUM SITE
COD081 961 518 EAGLE MINE
COD042167858 LINCOLN PARK
COD980499248 LOWRY LANDFILL
COD980499255 MARSHALL LANDFILL
CO7890010526 ROCKY FLATS PLANT (USDOE)
CO5210020769 ROCKY MOUNTAIN ARSENAL
COD980717953 SAND CREEK INDUSTRIAL
COD983769738 SMELTERTOWN SITE
COD980806277 SMUGGLER MOUNTAIN
COD983778432 SUMMITVILLE MINE
COD007063274 URAVAN URANIUM PROJECT (UNION CARBIDE)
COD980667075 WOODBURY CHEMICAL CO.
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AIR FORCE
PJKS
COLORADO
EPA ID# C07570090d
EPA
REGION 8
Jefferson County
Waterton
Site Description
The 464-acre Air Force Plant PJKS site is surrounded by approximately 4,700 acres of land
owned by Martin Marietta. Since 1957, wastes generated at the facility have consisted primarily
of spent solvents from equipment cleaning, contact and non-contact cooling water, and fuels
discharged as a result of engine and rocket testing. Contamination from trichloroethylene (TCE),
other hydrocarbons, rocket fuel components, and radiation was found in groundwater, surface
water, and soils. Contamination plumes were found in two groundwater zones. Some of these
plumes are moving off Air Force property and into the adjacent Martin Marietta property.
Several surface contamination sources also have been identified. The facility is located in a rural
area. Located nearby are major recreational areas used by local residents and visitors, including
Chatfield Reservoir, Roxbury State Park, and Waterton Canyon.
Site Responsibility:
This site is being addressed through
Federal actions.
NPL HISTORY
Proposed Date: 07/14/89
Final Date: 11/21/89
Threats and Contaminants
TCE, trichloroethane, freon, thorium, and gross alpha, beta, and gamma radiation have
contaminated the groundwater and soil. Brush Creek, located on the site, also contains
TCE. People who directly contact or accidentally ingest contaminated surface water,
groundwater, or surface wastes may suffer adverse health effects.
April 1995
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Cleanup Approach
The Air Force is continuing studies to identify the extent of contamination. The Air Force will
clean up the entire site using the results of these studies and, if necessary, will conduct early
source removal actions to eliminate immediate threats.
Response Action Status
Immediate Action: The Air Force's sampling revealed radiation contamination
traced to buried drums. These drums, buried in 1971, contained small quantities of a
low-level radioactive magnesium-thorium alloy. In 1988, the Air Force safely
removed the drums and transported them to a regulated disposal facility. In 1988, the Air Force
began removing abandoned underground storage tanks and associated contaminated soils from the
site. To date, 14 underground storage tanks have been removed. Uranium ore occurring
naturally in the area may also contribute to the levels of radioactivity found at this site.
Entire Site: The Air Force completed a draft report of an investigation of the entire
site for review by the EPA and the State. Further investigations have begun to
determine the nature and extent of contamination in deeper groundwater zones. The
Air Force also is conducting investigations of certain surficial contamination sources and other
groundwater zones. Cleanup strategies for the surface sources and groundwater contamination
also are being developed.
Site Facts: The Air Force is participating in the Installation Restoration Program (IRP), a
specially funded program established by the Department of Defense (DOD) in 1978 to identify,
investigate, and control the migration of hazardous contaminants at DOD facilities.
Environmental Progress
The removal of contaminated drums has reduced the potential for acute exposure to hazardous
materials at the Air Force Plant PJKS site while investigations are being completed.
April 1995 2 AIR FORCE PLANT PJKS
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ASARCO,
INCORPORATE
(GLOBE PLANT
COLORADO
EPA ID# COD007063530
A REGION 8
and Adams Counties
Denver
Site Description
The ASARCO, Inc.'s Globe Plant site spans approximately 89 acres in Denver, Colorado. The
site is located in an industrial, commercial, and residential area on the western edge of the South
Platte River and is in a neighborhood referred to as Globeville. Beginning in 1986, the Globe
Plant produced gold, silver, copper, and lead on site. In 1901, American Smelting and Refining
Company, later named ASARCO, Inc., bought the site and converted it to a lead smelter. In
1921, ASARCO, Inc. stopped lead production and began producing arsenic trioxide, which
continued until 1926. The plant was then converted to cadmium, with production continuing
until 1992. The plant currently produces lead oxide and occasionally thallium, indium, and other
high purity metals. Throughout site operations, runoff from the ASARCO facility would pass
through an industrial ditch and enter conduits of the South Platte River. In 1974, the Colorado
Department of Public Health and the Environment (CDPHE) collected water and sediment
samples from the industrial drainage ditch directly west of the plant and detected elevated
concentrations of cadmium, lead, and some other metals. Investigations finalized in 1992 showed
that groundwater beneath and downgradient from the Globe Plant has elevated levels of cadmium,
zinc, and arsenic. The contaminated groundwater plume extends as far as the South Platte River.
Sediments in the industrial drainage ditch and a detention pond also contain high concentrations
of metals. High concentrations of cadmium, lead, and arsenic were found in soils both on the
plant site and underlying residences surrounding the plant. Nearby wetlands and fisheries 15
miles downstream of the site are also threatened by contaminated surface water that has migrated
off site.
Site Responsibility:
The site is being addressed through
Federal, State and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 05/10/93
March 1995
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Threats and Contaminants
25]
Investigations have indicated elevated levels of cadmium, lead, and arsenic in
groundwater, surface water sediments, and soil at and near the site. Wetlands and
fisheries within 15 miles of the site also are threatened by contaminated surface water
migrating off site. Contaminated soil underlies the homes of 30 residents of nearby
Globeville. People could be at risk by touching or ingesting contaminated
groundwater, surface water, or soil.
Cleanup Approach
This site is being addressed in a long-term remedial phase focusing on the cleanup of the entire
site.
Response Action Status
Entire Site: The State of Colorado and ASARCO, Inc. reached an agreement on
cleanup measures for the site in 1992. These actions include: reducing toxic
emissions from the ASARCO Globe Plant; monitoring emissions from the plant;
treating groundwater; cleaning ditches around plant grounds; closing a hazardous waste pile on
the plant site; sampling community soils (residential, commercial and public properties); cleaning
up contaminated soils that exceed health-based standards; and providing a medical monitoring
program. Construction for these activities began in the spring of 1993. Site cleanup work is
expected to be completed in 1997. These services are being paid for by ASARCO, Inc., with
technical and administrative oversight from the Colorado Department of Public Health and the
Environment (CDPHE). The EPA is currently reviewing site studies and cleanup progress to
ensure that the remedy is protective of public health and the environment.
Site Facts: In December 1983, CDPHE sued ASARCO for damages to natural resources under
the Superfund law. As a result of the suit, in 1987, CDPHE and ASARCO agreed to conduct
joint studies to determine the extent and nature of site contamination and to characterize
remaining site wastes. In July 1993, a Consent Decree between CDPHE and ASARCO was
approved requiring ASARCO to implement the selected remedy at the site. Using a technical
assistance grant, the community is working with the EPA to review ASARCO's work.
March 1995
ASARCO, INCORPORATED (GLOBE PLANT)
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Environmental Progress
The EPA and State of Colorado have determined that no immediate actions are necessary while
cleanup of the site continues. The medical monitoring program is now two years old, and
ASARCO is entering its second season of cleaning up residential soils.
ASARCO, INCORPORATED (GLOBE PLANT)
March 1995
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BRODERICK W
PRODUCTS
COLORADO
EPA ID# COD000110254
EPA REGION 8
Adams County
Denver
Site Description
The 64-acre Broderick Wood Products site is a former wood treatment plant with two main
activities that have contributed to contamination: wood treatment operations between 1947 and
1981 and railroad shops on site before 1947. The wood preserving process used creosote and
pentachlorophenol (PCP) to treat power poles, fence posts, railroad ties, and other wood
products. Wastes were disposed of in various locations on the property, with the majority piped
to two unlined impoundments in the northwestern corner. These were called the "main" and
"secondary" impoundments, and were the primary sources of contamination on the site. The
main impoundment contained a surface layer of oil and grease, a water layer, and a sludge layer.
The secondary impoundment held mainly sludge. The combined contents totalled about 2,200
cubic yards. No industrial activities currently take place on the site. None of the former ponds
appear to have received plant waste water, although a number of waste pits have been discovered.
A water supply well on the site was abandoned in the early 1970s, but several homes to the north
of the site continue to use well water. Fisher Ditch distributes water to irrigation ditches that
flow to Copeland Lake, which is used for power plant cooling. Approximately 79,000 people
live within a 3-mile radius of the site; 2,900 people live within 1 mile. The nearest home is 500
feet from the site. Clear Creek, a sanitary landfill, and areas where sand and gravel mining have
occurred are located l/i mile to the north.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 09/08/83
Final Date: 09/21/84
Threats and Contaminants
Groundwater, surface water, impoundment sludges, and soil are contaminated with
various polynuclear aromatic hydrocarbons (PAHs), PCP, and volatile organic
compounds (VOCs). In addition, some soil is contaminated with various heavy metals.
People may incur health risks by coming into direct contact with or accidentally
ingesting contaminated groundwater or soil.
March 1995
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Cleanup Approach
The site is being addressed through two study areas: the surface impoundment sludges; and soils,
ground water, structures, and their contents.
Response Action Status
Surface Impoundment Sludges: Under an Administrative Order issued by the EPA
in 1990, the parties potentially responsible for site contamination excavated impoundment
sludges and stored them in lined impoundments. In 1992, the EPA modified the selected
remedy addressing these sludges, including reclaiming and incinerating the residues. Cleanup
actions were completed in 1993. The site is fenced and posted.
Soils, Ground water, and Structures: In 1990, the potentially responsible parties
[> began an investigation, under EPA oversight, that explored the nature and extent of
pollution at and around the property. The investigation specifically targeted
impoundment water, soils beneath impoundments, groundwater, surface water, surface and
subsurface soils, and structures located on the site. The study was completed in mid-1991. The
EPA selected a remedy for these areas in early 1992 that calls for bioremediation of soils and
sediment, closure of the previously excavated impoundments, bioremediation of groundwater,
reclamation of materials in tanks and containers, and demolition of contaminated structures on the
site. The cleanup will be conducted in two phases. Phase I was completed in early 1994, and
included all remedies except for groundwater cleanup. Phase II, focusing on groundwater
cleanup, is expected to be completed in the late 1995.
Site Facts: The EPA signed a partial Consent Decree in 1986, requiring Broderick Investment
Company to conduct a site investigation. An Administrative Order was signed in 1990, requiring
the potentially responsible parties to conduct cleanup of the surface impoundment sludges. In
1992, EPA ordered the potentially responsible parties to conduct the remaining design and
cleanup work. When they elected not to comply, EPA initiated the design work. A case to
recover EPA's costs is now pending in federal court.
Environmental Progress
The installation of a security fence and the excavation and reclamation of the surface
impoundments sludges at the Broderick Wood Products site have reduced the potential for
exposure to hazardous materials and migration of hazardous substances while final cleanup of the
site groundwater is underway.
March 1995 2 BRODERICK WOOD PRODUCTS
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CALIFORNIA
COLORADO
EPA ID# COD980717938
EPA REGION 8
Lake County
100 miles west of Denver
Site Description
The California Gulch site is a 130 year old mining area covering l8l/2 square miles of a
watershed area that drains along California Gulch to the Arkansas River. Starting in 1859, the
area was mined extensively for gold, lead, silver, copper, zinc, and manganese. California
Gulch collects numerous amounts of waste draining from mining, milling, and smelting
operations. Miners built the Yak Tunnel to drain water from the mine works and to make
mineral exploration and development easier. This tunnel drains hundreds of miles of mine
workings along its 4-mile underground course and discharges approximately 210 tons of various
heavy metals each year into California Gulch. Seventy-five known mills dumped tailings into
over 5 miles of this area. Six impounded tailings dumps surround the nearby city of Leadville.
Seventeen smelters operated at various times around the city and processed silver, lead, and zinc.
Heavy metal residues are present in much of the city. Contaminated runoff flows through local
town storm drains and city streets. The Arkansas River, which receives water from the
California Gulch, has been classified as a recreational resource, and is heavily used for irrigation,
livestock watering, public water supplies, and fisheries. Approximately 4,000 people live in
nearby Leadville and Lake County.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 12/30/82
Final Date: 09/08/83
Threats and Contaminants
The primary contaminants of concern affecting surface water, sediments, and
groundwater are the heavy metals cadmium, copper, lead, arsenic, and zinc. The
water in several shallow groundwater wells in California Gulch and in some private
wells has been shown to exceed the EPA's drinking water standards for cadmium and
zinc. Arsenic, cadmium, and lead are present in waste piles and soils. Adverse effects
on the fish population have been observed in the Arkansas River. Contaminants have
degraded vegetation in pastures downstream, and some plant tissues contained levels of
metals toxic to livestock and wildlife. Water in the main stem of California Gulch is
unsafe to drink. Other potential threats to the health of the resident population include
direct contact with contaminants in the soil.
April 1995
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Cleanup Approach
This site is being addressed in six stages: immediate actions and five long-term remedial phases
focusing on cleanup of the Yak Tunnel, ground water and surface water, mine waste rock and
tailings, smelters and slag, and residential areas.
Response Action Status
Immediate Actions: In 1986, EPA emergency response workers extended public
water supply system lines to residences using private wells. In 1990, a potentially
responsible party improved the area storm water drainage system in east Leadville to
prevent contaminated surface water from coming into contact with residential areas. As a result
of a site-wide settlement with the major responsible parties, EPA and the responsible parties are
proceeding with early response actions to address the most serious areas of contamination
throughout the site. These early actions will address mine tailing impoundments and mine waste
rock piles at the site, as well as stream sediments in the Oregon and California Gulches.
Yak Tunnel: In 1991, the EPA modified its 1988 remedy to treat the flow of acid
water from the Yak Tunnel and to prevent the uncontrolled release of tunnel drainage
to the environment. The modified remedy features installing a surge pond to capture
tunnel drainage and dissipate the effect of surges from the tunnel on the California Gulch and the
Arkansas River, constructing a permanent system to treat the tunnel water before discharging it,
installing a flow control bulkhead in the tunnel to stop the uncontrolled discharge of mine
drainage, sealing shafts, drill holes, and fractured rock, and diverting surface water to reduce the
amount of water entering the tunnel, establishing a surface water and groundwater monitoring
system, and preparing a contingency plan. Under EPA direction, the parties potentially
responsible for site contamination are designing the remedies and conducting the cleanup. The
parties finished building the surge pond and filter unit in 1989 and completed the permanent
treatment plant in 1992. Remaining Yak Tunnel activities are scheduled for completion by mid-
1995.
Groundwater and Surface Water: Full-scale studies of surface water and
groundwater began in 1991 including surface water sampling, stream-bed sampling,
and toxicity testing of the California Gulch, adjacent drainages, and the Arkansas
River. As part of a larger groundwater study, 56 additional monitoring wells and piezometers
were installed.
Mine Waste Rock and Tailings: The potentially responsible parties began an
investigation of primary waste sources from the site in 1991. The investigation is
exploring the extent of lead and zinc contamination in the mine waste rock and
fluvial and impounded tailings. Runoff from these sources drains into surface water and
groundwater. At the completion of these investigations, the EPA will identify alternatives for
cleaning up the waste.
April 1995 2 CALIFORNIA GULCH
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a
Smelters and Slag: In 1991, the potentially responsible parties began
investigations to determine the nature and extent of heavy metal releases from
smelters and slag. Once the investigation is completed, expected in 1996, alternative
Residential Areas: In 1991, the EPA released a Preliminary Human Health Risk
Assessment for the site. The EPA and the potentially responsible parties are
undertaking intensive studies of the concentration of lead, cadmium and arsenic in
residential soils and household dust. These and other studies will be used to define the nature
and extent of contamination and resulting risk in this area of the site, as well as the best
alternatives for cleanup.
Settlement Agreements: In August 1994, the EPA reached an agreement with
ASARCO, Incorporated, and Resurrection Mining Company (a subsidiary of the
Newmont Mining Company) to address the site. This settlement defines site areas of
responsibility for each of these companies, as well as the U.S. Government. The settlement does
not determine the type of cleanup work to be conducted; however, to reach agreement on the
terms of the settlement, a range of possible cleanup options was considered. The final decision
on the type and extent of work to be conducted will depend on the final results of the site
investigations, risk assessment, detailed feasibility studies, and public input. The public will have
an opportunity to comment on the results of these studies and any proposed cleanup plans during
public comment periods and public meetings.
Who Pays? The terms of this settlement provide for the cost of the cleanup to be paid for by
ASARCO, Resurrection, the United States, and the State of Colorado. The potentially
responsible parties alleged that the United States was liable for mining operations conducted in
Leadville during World War II. The potentially responsible parties also alleged that the State of
Colorado Department of Transportation was liable for spreading slag fines as part of its road
sanding program. To settle these alleged liabilities, the United States and State of Colorado are
paying $6.1 million and $225,000 respectively to the potentially responsible parties to be used to
address site cleanup.
Other settlements reached during 1993-1994 include:
/ Res ASARCO Joint Venture paid $8.5 million for government response costs for
previous site work, including addressing contamination in the Yak Tunnel.
/ Denver & Rio Grande Western Railroad paid $1.25 million to the EPA to cover past
cleanup costs and agreed to clean up certain slag piles throughout the site.
/ Hecla and the United States will pay $688,000 for cleanup of the Malta Gulch tailing
impoundments.
Site Facts: ASARCO has agreed to conduct a lead risk-reduction program known as the "Kids
First Program." An interim analysis of risks to children from lead is the basis for this program.
CALIFORNIA GULCH 3 April 1995
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Kids First Program
The Kids First Program is intended to reduce overall lead-related risk to children in
Leadville, regardless of the source of lead. This program is one of the first of its
kind. It will address risks from the lead not only in soils, but also in dust, paint, and
water. Participation by residents in this program is completely voluntary. The EPA and
ASARCO have also agreed to evaluate a multi-media Lead Risk Reduction Program during the
feasibility study. If approved by the EPA, the Lead Risk Reduction Program may be
implemented as a final remedy for the residential areas. This program would address multiple
sources of lead in the community including soil, pipes, paint, and indoor dust, and would be
funded by a specially-established trust fund. The Lake County Health Department, Colorado
Department of Public Health and the Environment, and the public will be asked to play a
significant role in the development and implementation of both the interim Kids First Program
and the Lead Risk Reduction Program.
Environmental Progress
The extension of the public water supply has provided safe drinking water for affected area
residents. Operation of the Yak Tunnel treatment facility in 1992 has improved water quality
significantly in California Gulch and the Upper Arkansas River. Metal-contaminated sludges
resulting from treatment plant operations are being shipped off site for recycling at the potentially
responsible party's East Helena Smelter. This resource recovery initiative eliminates the need for
sludge disposal in landfills and prevents additional pollution at the smelter through substitution of
metal fluxing agents.
Site Repositories
Lake County Public Library, 1115 Harrison Avenue, Leadville, CO 80461, (719) 486-0569
Colorado Mountain College, Timberline Campus Library, Leadville, CO 80461,
(719) 486-2015
EPA Superfund Records Center, 999 18th Street, 5th Floor, Denver, CO 80202-2466,
(303) 293-1807
April 1995 4 CALIFORNIA GULCH
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CENTRAL CITY -
CLEAR CREEK
COLORADO
EPA ID# COD980717557
REGION 8
and Gilpin Counties
ss west of Denver
Other Names:
Argo Tunnel
Big Five Tunnel
Burleigh Tunnel
Central City Mining District
Gregory Incline
National Tunnel
Quartz Hill Tunnel
Chase Gulch
Site Description
Gregory Gulch
Golden Gilpin Mill
Boodle Mill
Clay County Tailings
North Clear Creek
Tailings
Black Eagle Tailings
Little Bear Creek
Tailings
McClelland Tailings
The Central City-Clear Creek site is located approximately 30 miles west of Denver, Colorado.
The site boundary has not been narrowly defined because of the nature of the contamination.
Extensive gold mining took place in the Clear Creek Watershed during the late 1800s. Hundreds
of mine waste rock and tailings piles remain as a result of operations. In addition, numerous mine
tunnels, built for ore haulage and mine water drainage, continue to drain acid water into the
Clear Creek Watershed. Investigations at the site have involved identifying and prioritizing
contamination within the approximately 400-square-mile drainage basin of Clear Creek. Clear
Creek has three major tributaries—South, West, and North Clear Creek—as well as numerous
smaller tributaries. Designated uses of Clear Creek include agricultural, recreational, and
drinking water supply uses. Recreational uses in Clear Creek include fishing, kayaking, rafting,
tubing, gold panning, and wildlife watching. Clear Creek and its tributaries are used in whole or
in part as a drinking water source by several municipalities including Georgetown, Idaho Springs,
Black Hawk, Golden, Westminster, Thornton, and Arvada. The Upper Clear Creek drainage
basin is located mostly in Clear Creek and Gilpin Counties. The 1988 population estimates show
2,649 residents in Gilpin County and 7,379 residents in Clear Creek County. More densely
populated areas include the towns of Silver Plume, Georgetown, Empire, and Idaho Springs in
Clear Creek County, and Central City and Black Hawk in Gilpin County. Land uses in Clear
Creek and Gilpin Counties include tourism, commerce, recreation, and to a limited extent,
ranching and agriculture. Areas of both counties were extensively mined in the past because of
the abundance of precious and base metals. Active mines are still present at some locations in
the counties. In October 1991, limited stakes gaming was legalized in the towns of Black Hawk
and Central City. This new industry is changing the land use and population density in these
areas.
Site Responsibility:
This site is being addressed through
Federal, State, and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 07/23/82
Final Date: 09/08/83
April 1995
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Threats and Contaminants
Soils, including tailings and waste rock, contain heavy metals such as arsenic,
cadmium, chromium, copper, and lead. Children may be at risk from playing on these
contaminated areas. Groundwater and surface water also contain heavy metals. People
can be exposed to site contamination by drinking contaminated groundwater from
private wells. The aquatic environment has been, and continues to be, severely
affected by the elevated levels of metals in Clear Creek and its tributaries.
Cleanup Approach
The site is being addressed by immediate actions and three long-term remedial phases directed at
cleanup of mine discharges, tailings and waste rock piles, and other areas.
Response Action Status
Immediate Actions: In 1987, the EPA built a new retaining wall to support the
waste rock and tailings known as the Gregory Incline mine dump. The EPA
decreased the slope of the waste pile and replaced the old retaining wall to prevent it
from collapsing into North Clear Creek. In 1987, the EPA surveyed local households to
determine whether residents were using contaminated water from their private wells. Of the
wells tested, one showed significant levels of contamination from cadmium. The EPA provided
the residents with bottled water as an interim measure until their home could be connected to the
Idaho Springs municipal water supply. Additionally, EPA connected four other nearby
residences to the city water supply; these wells were at risk from future contamination because
they drew water from the same aquifer. The Colorado Department of Public Health and
Environment conducted a second survey in 1989, and two new problem wells were identified.
These wells will be addressed by future actions. In 1991, the EPA removed mercury and
mercury-contaminated waste from an abandoned trailer near Idaho Springs. The mercury was
likely left over from a mine laboratory that operated inside the trailer. The trailer was an
attractive place for children to play. Since limited stakes gaming was legalized in Central City
and Black Hawk in 1991, the EPA has successfully negotiated five Administrative Orders on
Consent with gaming developers. The orders require the developers to cleanup their property
prior to the construction of casinos or casino-support facilities. Several other Consent Orders
with developers are anticipated, resulting in private cleanup of site areas that would otherwise
have been cleaned up at government expense.
April 1995
CENTRAL CITY-CLEAR CREEK
-------
Mine Discharge Treatment of Surface Water Contaminants: The EPA and
the State plan to construct a wetland passive treatment system to treat the mine tunnel
discharge from the Burleigh Mine Tunnel before it reaches Clear Creek. The
Colorado Department of Public Health and Environment already has constructed a pilot-treatment
system to determine the ability of passive treatment to meet water quality standards. Results
have been promising. An active treatment system using chemical precipitation will be built to
treat the Argo Mine Tunnel discharge. These systems are being designed to remove dissolved
and suspended metals in the mine drainages and decrease the acidity of the mine drainages to
meet water quality standards. In the future, the State and the EPA will consider treating other
mine tunnel discharges in the Clear Creek Watershed. The technical design for this remedy is
expected to be completed in mid-1995.
Tailings/Waste Rock Remediation: Erosion and stormwater control measures
were completed at the Argo Tunnel and the Gregory Incline Mine Waste Piles in
1991. The majority of the Gregory Incline Tails were removed by a casino developer
in 1994. The McClelland Tailings Pile was capped in 1993 and the Black Eagle Tails were
stabilized and capped in 1994. Capping or erosion control measures are now underway at several
other tailings and waste rock piles. These efforts are expected to continue until 1997. The EPA,
the State, and local officials are evaluating institutional measures as a means of controlling threats
that future development on the tailings and waste rock piles could pose to people or the
environment. Additional cleanup activities are underway to control acid mine drainage, remove
contaminated sediment from the National Tunnel in Black Hawk, and replace the wetland. These
activities are expected to be completed in 1995.
Other Areas: In addition to the activities listed above, several other restoration and
cleanup initiatives are underway. Clear Creek, near the Argo Tunnel, and Big Five
Tunnel in Idaho Springs, are being restored. The Coors Brewing Company sponsored
an effort to restore Clear Creek near the McClelland mine tailings in Dumont. The Colorado
Department of Transportation paid for the capping of mine tailings on a highway right-of-way
adjacent to Clear Creek and across the river from the McClelland mine tailings.
Site Facts: The Colorado Department of Public Health and Environment is seeking volunteers
for private drinking water well testing. This will be the third such solicitation. Owners of wells
contaminated with metals from mining activities will be eligible to receive bottled water and may
be connected to a public water supply system.
CENTRAL CITY-CLEAR CREEK 3 April 1995
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Environmental Progress
The construction of a new retaining wall to support the waste rock and tailings has prevented
further spread of contamination from the Gregory Incline Mine Dump into North Clear Creek.
The EPA provided affected residences with bottled water prior to connecting them to the
municipal water supply and later connected four other residences to the city water supply.
Additional stabilization of tailings and waste rock piles is underway. Remedies have been chosen
for the treatment of the acidic water, and the design of both systems is underway. These cleanup
activities have reduced threats to the nearby population and environment while cleanup continues.
April 1995
CENTRAL CITY-CLEAR CREEK
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CHEMICAL S
COMPANY
COLORADO
EPA ID# COD00743162CJ
Site Description
EPA REGION 8
Denver County
miles northwest of Stapleton
International Airport
Other Names:
Dahlia NPL Staging Area
The Chemical Sales Company site is located in a predominantly light industrial area in
northeastern Denver and covers approximately 5 square miles. The company is a wholesale
distributor of commercial/industrial chemicals, detergents, and water leisure products. Operations
include the storage and repackaging of bulk chemicals from rail cars and drums. A warehouse
located on site has been owned and operated by the company since 1976. Surface and
underground storage tanks, ranging in size from 5,000 to 15,000 gallons, were installed between
1976 and 1977. In 1981, as a result of EPA-sponsored national random sampling of drinking
water, the groundwater in the South Adams County Water and Sanitation District was found to be
contaminated with organic chemicals. This lead to the discovery of Chemical Sales Company as
the main source of the organic chemical contamination. There have been three reported spills at
the site, one of which occurred in 1985, when approximately 200 gallons of methylene chloride
were spilled as a result of a spigot breaking off a tank. In 1986, the discharge of contaminated
water from the company property was discovered by the Denver Fire Department. The transfer
pipe gallery between the storage tanks and the loading dock had filled with runoff water. The
pipe gallery was pumped into a nearby drainage ditch along the railroad tracks. The third release
was a methanol spill, which occurred in 1990, when approximately 3,700 gallons of methanol
were released.
Site Responsibility:
This site is being addressed through
Federal, State, and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 06/24/88
Final Date: 08/30/90
Threats and Contaminants
High concentrations of volatile organic compounds (VOCs), such as tetrachloroethylene
(PCE), trichloroethylene (TCE), methylene chloride, and chloroform, were detected in
groundwater samples. The EPA detected VOCs in the soil in and around the Chemical
Sales Company property. Ingestion of contaminated groundwater or inhalation of
vapors while using groundwater pose the greatest risks. Health risks exist for
individuals who come in direct contact with the contaminated soil or groundwater. The
site has been identified as a potential source of contamination of the South Adams
County alluvial aquifer.
April 1995
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Cleanup Approach
The site is being addressed in four stages: initial activities and three long-term remedial phases
focusing on controlling the source of contamination and cleanup of the groundwater, and the
residential wells.
Response Action Status
Initial Actions: In the summer of 1986, South Adams County Water and Sanitation
District (SACWSD) connected its water system to a temporary treatment system to
provide safe drinking water to its customers. At the same time, the EPA began
connecting about 400 residences, who were using private alluvial wells for indoor purposes, to
the SACWSD system. In 1987, construction began on a permanent treatment plan for the
SACWSD (Klein Water Treatment Plant). This project was completed and put on line in 1989.
In 1989, the EPA removed leaking and corroded drums containing contaminated soils, solvents,
and liquids discovered during the EPA's investigation. Drums were removed to a federally
approved disposal facility.
Source Control: Under EPA oversight, Chemical Sales initiated an investigation in
1989 to determine the source of the contamination, and to identify alternative
technologies to control the sources of the contamination. The study, completed in
February 1991, found that the main source of pollution is contaminated soils and recommends the
following remedy: treating contaminated soils through the use of soil vapor extraction. Later in
1991, the remedy was modified to incorporate air sparging with soil vapor extraction and a pump
and treat system to address the source area. The technical design for these remedies began in
early 1992 and is expected to be completed in 1995.
Groundwater: The EPA initiated an investigation in 1989 to determine the extent of
groundwater contamination at the site. The EPA collected groundwater samples from
80 wells in the site area. Based on the site investigation results, the EPA selected
installation of groundwater extraction wells to prevent further migration of groundwater
contamination and treating contaminated groundwater through the use of air stripping. The
cleaned water will be reintroduced into the aquifer. Design activities for this remedy began in
early 1992. The design is expected to be completed in mid-1995.
Residential Wells: In 1990, the EPA began an investigation to determine how many
private well owners were using the water for drinking purposes and not hooked up to
the SACWSD system. In August 1990, a Colorado Department of Health and
Tri-County Health survey identified 12 residences that were using shallow wells located within
contaminated portions of the alluvial aquifer. Based on the site investigations, the EPA proposed
connecting the affected residences to the South Adams County Water and Sanitation District
water supply system. The above residences were connected to the municipal water system in
1992. Three final residences are scheduled to be connected in mid-1995.
April 1995 2 CHEMICAL SALES COMPANY
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Environmental Progress
By removing drums containing hazardous materials, disposing of them at an approved facility,
and securing the area, the EPA has reduced the threat of exposure to dangerous chemicals at the
Chemical Sales Company site. Additionally, by hooking residences up to the municipal water
system, the EPA has provided those residences with safe drinking water.
CHEMICAL SALES COMPANY
April 1995
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DENVER RADI
SITE
COLORADO
EPA ID# COD980716955
Site Description
EPA REGION 8
Denver County
Denver
Forty-nine properties in Denver are contaminated with radioactive soils and debris abandoned
after the collapse of the city's World War I-era radium industry. Following the demise of the
industry in the late 1920s, people soon forgot about the origin, location, and nature of the
refining wastes. An EPA investigator discovered the situation in 1979 while reviewing some old
documents. The State, with help from several agencies, undertook an extensive study and found
35 sites where radium had been processed, refined, or fabricated into various devices or
products. The number of properties affected has since expanded to 49 in the metropolitan
Denver area. These 49 properties were combined into 9 groups for clean up including: 12th and
Quivas Properties; llth and Umatilla Properties; 1000 W. Louisiana Properties; Robinson Brick
Company (ROBCO) and Denver and Rio Grande Western (D&RGW) Properties; Card Property;
Open Lands; Denver Streets; Shattuck Chemical Property; and ROBCO-Non-Radioactive
Contamination.
Site Responsibility:
This site is being addressed through
Federal, State, and a potentially
responsible parry's actions.
NPL LISTING HISTORY
Proposed Date: 10/23/81
Final Date: 09/08/83
Threats and Contaminants
The soil is contaminated with radium, thorium, uranium, arsenic, and lead. Although
the immediate threat to public health and the environment is limited, redevelopment of
contaminated properties or mismanagement of the wastes could increase the risk of
exposure if contaminated materials are not removed and disposed of safely. The
principal threat arises from the buildup of radon gas in structures built over the
contaminated soil. In addition, direct contact with the wastes may pose a health risk.
Cleanup Approach
This site is being addressed in ten stages: emergency actions and nine long-term remedial phases
focusing on cleanup of the identified contamination areas and properties. Some of these separate
areas contain multiple long-term remedial phases.
April 1995
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Response Action Status
Emergency Actions: In 1985, EPA emergency workers arrived at an appliance
refurbishing facility to remove radon gas. They installed ventilation systems along
two sides of the operation's basement. This action resulted in a decrease of the
radon concentrations to levels well below EPA standards. In 1989, another system to vent high
levels of radon gas was installed at a construction contracting business. The venting system
decreased radon concentrations to below EPA standards.
12th and Quivas Properties: In 1987, the EPA selected a remedy for this portion
of the site which included excavating the contaminated soil lying in open areas and
under several structures on the properties and transporting the soil to a permanent
disposal site. Cleanup activities began in 1989 and were completed in the summer of 1991.
Workers removed 33,000 tons of contaminated soil and backfilled with clean soil, regrading to
the original contours. Where buildings were constructed over contaminated soil, cleanup workers
removed the floors to excavate underlying wastes, and then replaced the floors.
11th and Umatilla Properties: The EPA selected a remedy for the area in 1987.
Features of the remedy included excavating contaminated soil from open areas and
from under buildings and disposing of the contaminated material at a permanent
disposal facility. The EPA has removed over 90,000 tons of contaminated material from the
property and has replaced it with clean fill. All radiologic contamination from the site has been
removed. Remaining lead-contaminated soils were excavated, solidified, and transported to an
off-site disposal facility. This project was completed in 1993. The U.S. Bureau of Reclamation
is managing the transport and disposal of all wastes from the Denver Radium site.
1000 W. Louisiana Properties: The EPA selected a remedy for this portion of the
site in 1987. The remedy included demolishing the Creative Illumination building,
excavating the contaminated soil remaining on the 1000 W. Louisiana properties, and
transporting the contaminated material from the properties to the permanent disposal facility.
Cleanup activities began in 1989, with the demolition of the contaminated brick building at 1298
S. Kalamath Street. Workers have excavated 64,000 tons of contaminated soil, and demolished
one contaminated building. The EPA is leaving waste that extends under the streets in place, as
it does not pose a risk. The project was completed in 1991.
ROBCO and D&RGW Railroad Properties: The EPA selected a remedy for the
ROBCO property and the adjacent D&RGW Railroad property in 1986. The remedy
featured removing contaminated soil from the Robinson Brick Company property and
the D&RGW Railroad property, demolishing the contaminated laboratory and office buildings on
the ROBCO property and removing 200 cubic yards of debris, disposing of the contaminated soil
and debris at a permanent disposal facility, and continuing periodic ground water monitoring.
More than 96,000 tons of contaminated waste were excavated and disposed of safely. The clean
up work was completed in 1991.
April! 995 2 DENVER RADIUM SITE
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Card Property: The EPA selected a remedy for this portion of the site in 1987 which
featured: excavating 4,000 cubic yards of contaminated soil and sediments from the
Card property; temporarily storing this waste in reinforced synthetic bags placed inside
a building at the site; possibly staging or storing wastes from other subsites on the Card property,
but not more than 13,000 cubic yards total; removing all contaminated material to a permanent
disposal facility; and decontaminating and dismantling the True Truss building and disposing of
the material in a sanitary landfill. All plans for temporary storage of waste on the site were
abandoned when a permanent disposal facility became available. The EPA began excavation and
disposal of wastes in the summer of 1988 and completed these cleanup activities in the fall of
1989.
Open Lands: These properties comprise open areas throughout Denver. At these
sites, contaminated soils were replaced with clean fill dirt. Over 5,000 tons of
contaminated soils were removed from these properties. Cleanup of the properties was
completed in early 1994.
Denver Streets: In 1986, the EPA chose a "no action" remedy for several Denver
street segments where the subsurface contains contaminated paving materials. The
remedy is to leave the contaminated material in place; however, a management plan
governing routine maintenance, repair, and construction activities on the affected
streets has been established to ensure that the area is not disturbed or developed, and that any
contaminated excavated material is properly disposed of.
Shattuck Chemical Property: In 1992, the EPA selected a remedy for this portion
of the site which includes: demolition of the existing facilities; excavation, treatment,
and on-site disposal of an estimated 50,000 cubic yards of contaminated soils; and
institutional controls to assure protectiveness of the selected remedy into the future. Cleanup
activities began in 1992 and are currently on hold due to a cease and desist order filed by the
City and County of Denver against the Shattuck Chemical Company. The U.S. Department of
Justice, on behalf of EPA, has asked for a Federal District Court ruling to prevent enforcement
of the cease and desist order. Resolution of this issue is anticipated in late 1995.
ROBCO-IMon-Radioactive Contamination: During the cleanup of radioactive
contamination at the ROBCO site, non-radioactive soil contamination was discovered.
EPA has conducted additional investigations into the nature and extent of this
contamination. EPA selected a final remedy in 1992 that consists of capping the contaminated
soils with clean fill material. The cap will serve as a barrier to prevent direct exposure to the
metals contamination. Design of the remedy was completed in 1992, and cleanup actions are
scheduled to be completed in 1995.
DENVER RADIUM SITE 3 April 1995
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Environmental Progress
Extensive cleanup work has been completed at the Denver Radium Site, including the removal
and disposal of over 310,000 tons of contaminated materials. Additionally, cleanup actions have
addressed immediate sources of radon and have protected workers from short-term exposure.
Additional actions are currently underway at the Denver Radium Site, which will continue to
reduce sources and levels of contamination.
April 1995
DENVER RADIUM SITE
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EAGLE MINE
COLORADO
EPA ID# COD081961518
EPA REGION 8
Eagle County
8 miles west of Vail
Other Names:
New Jersey Zinc, Inc.
Gilman
Site Description
The Eagle Mine site includes the Eagle Mine workings; the town of Gilman, Colorado; the mine
tailings pond areas; Rex Flats; Rock Creek Canyon; and waste rock and roaster piles. This site
encompasses an area of approximately 5 to 7 miles along the Eagle River. Over the last 100
years, zinc miners deposited about 10 million tons of mine wastes and mill tailings along the
Eagle River. The mining conditions and wastes formed acid which leached toxic metals into
surrounding surface water and groundwater. Five major sources of contamination have been
identified at the site: ponds containing tailings over a total of 107 acres; roaster piles, five of
which are found at this site; a 25-acre pipeline corridor that extends from Rex Flats to the new
tailings pond; 12 major waste-rock piles that cover about 93 acres; and seepage from the flooded
mine. The closest residence to the Eagle Mine site is located approximately 1,000 feet to the
northwest. Minturn, the closest population center, has 1,500 people, and its filter ponds and
municipal wells lie 2,000 feet to the northwest of the mine tailings and across Cross Creek.
Minturn draws its public water supply both from area wells and from Cross Creek. A middle
school is located only 400 yards from the largest tailings pile.
Site Responsibility:
This site is being addressed through
Federal, State, and potentially
responsible parties' actions.
NPL LISTING HISTORY
Proposed Date: 10/15/84
Final Date: 06/10/86
Threats and Contaminants
ZEJ
Soil, surface water, and groundwater below the tailings piles and the now-flooded mine
contain various heavy metals including arsenic, cadmium, chromium, copper, lead, and
zinc. Fish populations have declined in the reaches of the river next to and below
mine waste areas. Water from two town wells located near the site could be
threatened. Wind-blown particulates from the tailings pile are of concern because of
the proximity of a middle school. Maloit Park is a wetland area located adjacent to the
New Tailings Pile and has been affected by surface water and groundwater flowing
from the pile and from mass wastage spreading from the pile.
April 1995
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Cleanup Approach
This site is being addressed in three stages: initial/emergency actions and two long-term remedial
phases focusing on cleanup of the entire site and the soils.
Response Action Status
Initial/Emergency Actions: Between 1976 and 1979, the mine owners undertook
early cleanup activities such as treating mine water, re vegetating small test plots
located in the Rex Flats and old tailings pond areas, and building surface water
diversion ditches along the old and new tailings ponds. Workers removed about half the tailings
deposited on Rex Flats and built a surface runoff ditch. They also built a seepage collection pond
and a sump and liming facility between the old tailings pond and the Eagle River. Around 1983,
when the mine was abandoned and the pumps were turned off, the mine began to flood.
Transformers containing poly chlorinated biphenyls (PCBs), located in the mine shaft, posed a
threat if flooded. EPA emergency workers removed the transformers from the shaft, secured and
stored them on site as usable products, and supplied the electricity needed to run the pump and
water treatment systems while the salvage operations were underway. The EPA also built dikes
in the mine to divert water from the upper mine areas and to prevent the water's release.
Entire Site: In 1988, the State selected a remedy for cleaning up the sources of
pollution at the site including: plugging the mine portals; removing the roaster piles,
Rex Flats tailings, and tailings pile and consolidating them in the "new" tailings pile;
capping the new pile and pumping groundwater; and monitoring the Eagle River. The State and
a potentially responsible party reached an agreement on performance of the long-term cleanup
action. To prevent discharge of contaminated water to the river from the mine, the former
owners built five concrete bulkheads in mine openings. Under State supervision, the former
mine owners plugged the mine and reworked many millions of cubic yards of mine tailings.
They have consolidated most of the wastes from the roaster piles, Rex Flats, and the old tailings
pile into the new tailings pile. In early 1990, however, it became apparent that problems had
developed with the ongoing cleanup. Mine seepage, a failed groundwater pump-back system,
and run-off from various tailings areas were discharging a large quantity of metals into the Eagle
River. In 1990, the State and the potentially responsible party agreed to locate a water treatment
plant on site and to collect and treat visible mine seepage and consolidated pile groundwater. In
the fall of 1992, the EPA evaluated additional cleanup measures and decided on a remedy in
March 1993. The measures included further collection of Eagle Mine seeps, accelerated
revegetation, and additional monitoring. The EPA also created more stringent cleanup standards
for the Eagle River.
Soils: In late 1991, an investigation began to explore the nature and extent of
contaminated soils at the Eagle Mine site. The study was completed in late 1993.
Soil metals levels were found to be of no concern in Minturn and the Middle School
area. Levels are elevated on the Maloit Park wetlands and in Oilman. A remedy for the soils
area of the site is expected to be selected soon.
April 1995 2 EAGLE MINE
-------
Site Facts: Under a 1994 Unilateral Administrative Order, the EPA directed the potentially
responsible parties to remove soils in Maloit Park, renovate the groundwater extraction trenches,
develop plans for restoring the wetlands, monitor and analyze run-off from waste rock areas, and
collect additional mine seepage. The remainder of EPA's selected remedy that calls for
biologically based in-stream standards is expected to be addressed through a Consent Decree
which is nearing finalization.
Environmental Progress
The EPA has taken emergency actions at the Eagle Mine site to remove the PCB-laden
transformers and to construct dikes to prevent the further spread of contamination. The EPA and
the State also removed a large quantity of hazardous materials from Oilman and Eagle Mine. To
date, most of the tailings and roaster pile material has been consolidated at the new tailings pile,
which is 80 percent capped. A groundwater extraction system is operational, and the mine is
plugged and nearly completely flooded. Water drainage treatment and river impact monitoring
will continue while long-term cleanup actions and additional site investigations are underway to
protect the Eagle River from contaminated runoff from the site.
Site Repository
Town Clerk's Office, Minturn Town Hall, 302 Pine Street, Minturn, CO 81645
EAGLE MINE
April 1995
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LINCOLN PA
COLORADO
EPA ID# COD04216785k
EPA REGION 8
Fremont County
Canon City
Other Names:
Uranium Mill
Cotter Corporation
Site Description
Beginning in 1958, the Cotter Corporation operated a uranium mill approximately IVfc miles from
the community of Lincoln Park, Colorado. Mill operations caused the release of radionuclides
and heavy metals into the environment. Contaminants migrated through the groundwater to
Lincoln Park prior to the construction of a dam on Sand Creek. Drinking water wells in the
impacted area have been abandoned and residents have stopped using groundwater for domestic
purposes. These homes have been connected to the Canon City water supply; however, some
individuals in Lincoln Park are still using groundwater for irrigation purposes. The Lincoln Park
area has approximately 3,500 residents.
Site Responsibility:
This site is being addressed through
Federal, State, and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 09/08/83
Final Date: 09/21/84
Threats and Contaminants
Groundwater underlying the mill area and the community of Lincoln Park is
contaminated with uranium, molybdeum, and other radionuclides. Soils hi the mill
area also are contaminated with similar uranium products. Drinking or otherwise
coming into contact with contaminated well water or soil may cause adverse health
effects. Wind-blown contaminants and contaminants in surface streams also pose
potential threats.
March 1995
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Cleanup Approach
This site is being addressed in a long-term remedial phase focusing on cleanup of the entire site.
Response Action Status
Entire Site: In 1988, the State selected a remedy to clean up the site by: connecting
area residences to an alternate water supply; pumping and treating the groundwater
above the dam on Sand Creek to remove the contaminants; flushing the contaminants
out of the water below the dam; revegetating the site; implementing air quality controls; and
stopping off-site groundwater migration. Area residences have been furnished with a safe
drinking water supply. A pilot groundwater treatment system has been completed. A risk
assessment of the site was completed in 1992 to determine the effectiveness of the selected
cleanup remedies; soil, vegetation, and sediment sampling is continuing. To date, the Cotter
Corporation has contained the contaminants from the uranium mill by using a groundwater cut-off
barrier and by pumping the water back into holding ponds. The company is currently designing
the final technical specifications for the selected remedies, scheduled to be completed by 1996.
Cotter Corporation has sampled soils in the Sand Creek drainage basin on site and is scheduled to
remove contaminated soils and place them in the main impoundment during 1995.
Site Facts: In 1988, the State and the Cotter Corporation signed a Consent Decree, under which
the Cotter Corporation agreed to implement a remedy to clean up the contamination at the site.
In addition, in 1988, a Memorandum of Understanding was signed between EPA and the State,
giving the State a lead role in overseeing clean up of the site. Currently, the State, EPA and
Cotter Corporation are participating in a Total Quality Environmental Management program to
resolve technical issues with the design of the remedy for the site.
Environmental Progress
Residences near the Lincoln Park site have been furnished with a safe drinking water supply. A
pilot groundwater treatment system project has been completed and containment measures have
been taken at the site to prevent uranium-contaminated groundwater from migrating off the mill
site. Cotter voluntarily cleaned up a railroad depot site under EPA and State oversight in Canon
City where spillage had occurred. Another railroad spill clean up at Prospect Street is underway.
Site Repository
Canon City Library, 516 Macon Avenue, Canon City, CO 81212
Colorado State Attorney General's Office
EPA Superfund Records Center
March 1 995 2 LINCOLN PARK
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LOWRY LA
COLORADO
EPA ID# COD98049
EPA REGION 8
Arapahoe County
2 miles east of Aurora
Other Names:
Lowry Disposal Area
and County of Denver Landfill
and County of Denver Landfarm
Denver Arapahoe Disposal
t ity
Site Description
The Lowry Landfill covers approximately 400 acres near Aurora, Colorado, a suburb of Denver.
It is estimated that approximately 138 million gallons of liquid industrial wastes were dumped
into about 65 unlined trenches or pits from 1966 until 1980. These wastes included sewage
sludges, metal plating wastes, petroleum-derived products, pesticides, and industrial solvents.
Municipal refuse was added to the pits to soak up the liquids. This industrial waste disposal
method (known as co-disposal) was discontinued in 1980. Beginning at that time, the landfill
accepted only solid waste for disposal. In addition to the industrial wastes at the site,
approximately 8 million tires were stockpiled in the 1970s in the hope that they might be recycled
as a source of fuel or other raw material. Over the years, the wastes have migrated into the
ground water and surface water. The area around the site is zoned for future industrial,
commercial, and residential development. The population within 1 mile is less than 500 people.
Approximately 5,000 people live within 3 miles of the site.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties' actions.
Threats and Contaminants
NPL LISTING HISTORY
Proposed Date: 09/08/83
Final Date: 09/21/84
Landfill solids, landfill gas, soils, sediments, and shallow ground water contain one or
more organic or inorganic contaminants. Although the shallow ground water is
contaminated, it is not used as a drinking water source. However, the potential exists
for the contaminants to migrate into the deep ground water, which is a source of
drinking water in the vicinity of the site. EPA has determined that the site does not
pose any immediate risks to human health.
April 1995
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Cleanup Approach
The site has been addressed through initial actions and a long-term cleanup approach focusing on
sitewide cleanup.
Response Action Status
Initial Actions: In 1984, the City and County of Denver built an underground
barrier wall and treatment system. The wall functions as a dam to contain and collect
shallow ground water, which is pumped into storage tanks and piped to an on-site
plant for treatment. The treated water is discharged into an underground gravel drain off site,
where it slowly seeps into the ground water. In 1989, Waste Management of Colorado, Inc.
(WMC), under contract with Denver, began shredding and storing discarded tires that were
stockpiled at the site. The shredding operation was completed in the spring of 1992. In 1990, the
EPA bulked and removed drums containing wastes, and treated the liquids in the on-site
treatment plant. In 1992, WMC completed the construction of a collection and treatment system
to prevent contaminated surface water from flowing off site. This system was put into full-scale
operation in early 1993. In the fall of 1994, Denver, WMC, and Chemical Waste Management,
Inc. (CWM) received approval from EPA and the Colorado Department of Public Health and
Environment to dispose of solid and liquid wastes that were stored on the command post drum
storage pad. Disposal of these wastes was completed in early 1995. Approximately 4,217 drums
of waste were disposed of in accordance with all pertinent environmental regulations.
Sitewide Remedy: In early 1994, the preferred alternatives for cleaning up each
environmental media (ground water, landfill gas, landfill solids, soils, surface water,
and sediments) were combined to form the selected sitewide remedy. The selected
remedy includes: extraction and treatment of contaminated ground water and leachate; collection
and treatment of contaminated landfill gas; monitoring of all environmental media; placement of
an additional cover on the north face of the landfill mass; and excavation, treatment, and disposal
of contaminated solids (including drums, drum contents, and contaminated soils) in the former
tire pile area. The design of cleanup remedies began in early 1995 and is scheduled for
completion in 1996.
Site Facts: To date, there have been two de minimis (small party) settlements in which EPA
collected a total of $1,287,360.78. Also, there have been four bankruptcy settlements in which
$6,970,000 were collected. In 1994, the EPA issued a Unilateral Administrative Order that
required the 34 potentially responsible parties to perform the design of the remedy and implement
the cleanup activities. On January 17, 1995, Denver, WMC, and CWM submitted a notice of
intent to comply with the Order. Denver, WMC, and CWM submitted this response on behalf of
themselves and 21 other potentially responsible parties, all of whom had previously entered into
private settlements with Denver, WMC, and CWM.
April 1995 2 LOWRY LANDFILL
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Environmental Progress
The existing underground ground water barrier wall at the northern site boundary restricts
contaminated ground water from migrating away from the site. Contaminated ground water
currently is collected at the barrier wall and pumped to an on-site treatment plant. These
activities, in addition to the removal of drums and other wastes at the Lowry Landfill site, have
reduced the potential of exposure to site contaminants while final site cleanup remedies are being
designed.
LOWRY LANDFILL
April 1995
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MARSHALL LA
COLORADO
EPA ID# COD98049925
Site Description
EPA REGION 8
Boulder County
Town of Marshall
The Marshall-Boulder Landfill, covering 160 acres, is located 1A mile south of Colorado
Highway 170 and is bounded on the east by South 66th Street. Marshall Reservoir is located
upstream of the site, about 2,000 feet to the west. The site comprises two 80-acre sections that
were operated as a landfill until December 1991. Between 1965 and 1974, the landfill accepted
unstabilized sewage sludge and many unidentified and potentially hazardous wastes. Septic
wastes, and possibly liquid industrial wastes, also were disposed of off site in two septic ponds.
The ponds are now closed. In 1981, landfill leachate was observed seeping into the community
ditch that carried drinking water from the nearby Marshall Lake to the City of Louisville, and
that also conveyed irrigation water for downstream ranchers.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parlies' actions.
NPL LISTING HISTORY
Proposed Date: 07/23/82
Final Date: 09/08/83
Threats and Contaminants
Volatile organic compounds (VOCs) and inorganic chemicals have been detected in the
groundwater both on and off site and in surface waters on site. Drinking contaminated
groundwater could present a health threat to individuals.
March 1995
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Cleanup Approach
Response Action Status
Initial Actions: In 1984, Landfill, Inc. installed a 60-inch pressurized pipeline to
protect local drinking water supplies by transporting the water across the landfill.
Groundwater and Surface Water: The selected groundwater and surface water
cleanup remedies to address VOC and inorganic chemical contamination include:
fencing, regrading, and planting of the northern portion of the inactive landfill;
installing a groundwater collection and treatment system (allowing some contaminants to settle
out, exposing the groundwater to air to allow organic contaminants to evaporate, chemical
treatment to remove metals, and recapturing the contaminants in a carbon filter before releasing
to the air) and discharging the treated water to Cowdery Drainage; monitoring groundwater and
surface water; and implementing landfill improvements including regrading, re vegetating, digging
of perimeter ditches, and installing fences. The potentially responsible parties, under EPA
oversight, completed construction of the water treatment plant and groundwater collection system
in the spring of 1993.
Site Facts: Under an Enforcement Order in 1984, Landfill, Inc. installed a pressurized pipeline
to protect drinking water supplies. The EPA negotiated Consent Decrees with the potentially
responsible parties, including the City of Boulder, Landfill, Inc., and the Cowdery Company, to
perform the cleanup actions.
Environmental Progress
All construction is complete and a water treatment plant is now treating contaminated
groundwater, ensuring the ongoing reduction of risk to public health and the environment.
March 1995 2 MARSHALL LANDFILL
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ROCKY FLATS
(USDOE)
COLORADO
EPA ID # CO7890010526
EPA REGION 8
Jefferson County
16 miles northwest of Denver
Site Description
The Rocky Flats site covers approximately 6,500 acres of United States Department of Energy
(USDOE) land. Originally established by the Federal government in 1951, the facility currently
is under contractor management. Rocky Flats has produced plutonium triggers for the USDOE
nuclear weapons programs. Site operations have included recovering and reprocessing plutonium
from old weapons and manufacturing residues, performing laboratory research, and
manufacturing weapon parts from "high-tech" metals. In 1989, Rocky Flats was investigated by
the EPA, the Department of Justice (DOJ), the FBI, and the DOE Inspector General for
violations of environmental statues. Plutonium operation was suspended at that time. In 1992,
the mission changed from defense production to environmental restoration, waste management,
and economic conversion. Rocky Flats presently stores hazardous waste, and houses the largest
plutonium inventory in the country. In February 1993, USDOE received approval to restart
Building 707 for stabilization of plutonium residues. Site contaminants have spilled onto the
ground and into water supply drainages. The USDOE identified over 2,000 waste streams that
the production processes generated at the site. Other major environmental concerns at the site
encompass 178 identified disposal areas resulting from past waste management practices,
including a series of evaporation surface impoundments, old process pipelines and underground
tanks, aqueous spray irrigation fields, two on-site landfills, leaking drum storage areas, and
several disposal trenches. USDOE has recently identified another 79 areas of concern, which
will be incorporated into investigations administered through the clean up agreement with the
EPA. Over 2 million people live within 50 miles of Rocky Flats; over 300,000 live within 10
miles.
Site Responsibility:
This site is being addressed through
Federal actions.
NPL LISTING HISTORY
Proposed Date: 10/15/84
Final Date: 10/04/89
Threats and Contaminants
Groundwater contains various volatile organic compounds (VOCs), radionuclides, and
heavy metals. Soil and surface water are contaminated with plutonium, uranium, and
americium. Shallow groundwater in the southern section of the site (the Hillside area)
and the eastern section of the site (the 903 Pad, East Trenches, and Mound Areas) are
contaminated with high levels of VOCs. Air could potentially become contaminated
with radioactive plutonium, uranium, and americium. People could be exposed to
chemicals on site by touching, inhaling, or ingesting contaminants in soil, air,
groundwater, and surface water.
April 1995
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Cleanup Approach
This site is being addressed in multiple stages: interim actions and a total of 16 long-term
remedial phases focusing on addressing contamination at the Hillside 881 Area; the 903 Pads,
East Trenches, and Mound Areas; Off-site Releases; Solar Ponds; Woman Creek; Walnut Creek;
Present Landfill; Original Process Waste Lines; Low priority Areas; 700 Area, Other Outside
Closures, West Spray Field, 400/800 Area, 100 Area, Radioactive Sites, and Inside Building
Closures.
Response Action Status
Interim Actions: In 1987, the USDOE removed more than 20,000 cubic yards of
sludge from evaporation ponds. The removed sludge has become a source of
problems for USDOE. USDOE has dewatered the ponds through the implementation
of an interim response action for the solar ponds. Several additional interim actions have been
approved for this site. These actions will be undertaken in the near future.
Hillside 881 Area: In 1988, the USDOE completed draft reports on the nature and
extent of contamination within the Hillside 881 Area. Construction was completed on
a french drain collection system and associated treatment plant intended to stop
contaminants from moving through the groundwater. Additional investigations were completed in
early 1990 that included drilling and sampling of soil, water, ah", and biota. The USDOE began
treating the groundwater hi early 1992.
903 Pad, East Trenches, and Mound Areas: This area may be the most
complex and difficult to address on the site, due primarily to the high concentrations
of radioactive contaminants that must be addressed, as well as surface water seeps,
which have required the implementation of a number of interim cleanup measures. An interim
remedy was selected in early 1991 which consisted of a surface water collection and treatment
system. This system is presently operating. Additional sampling and analysis began in mid-1991
on soil, sediments, water, and biota. A second interim measure has been developed, approved,
and is being implemented to address potential releases from this area of the site to an adjacent
drainage. The second interim measure has successfully demonstrated the viability of using soil-
vapor extraction to treat VOC-contaminated soils and groundwater.
Off-site Releases: These areas consist of two reservoirs that are used as drinking
water supplies for approximately 250,000 people, a third irrigation reservoir, and land
used for recreational and agricultural purposes. The USDOE conducted two
preliminary risk studies that have been used to focus the investigation of these areas. An
investigation work plan was submitted in mid-1991 and has been approved. The investigation is
currently underway and scheduled to be completed in 1999.
Solar Ponds: An interim cleanup action was selected in 1992, which includes the
construction of storage tanks and a water distillation unit to dewater/desludge the
pond. These actions were completed in 1993. A draft interim plan for in-place closure
of the ponds was recently submitted for review. A groundwater collection system continues to
operate.
April 1995 2 ROCKY FLATS PLANT (USDOE)
-------
Woman Creek: This area encompasses the stream, two ponds on the stream, and a
number of disposal sites within the basin including an abandoned landfill, disposal
trenches, and former waste storage areas. The drainage basin receives surface water
flows and groundwater seepage from contaminated and active industrial areas of the site, which
potentially could affect downstream surface water supplies. An investigation work plan has been
submitted and approved. Field work began in late 1992 and the first phase of the investigation
has been completed.
Walnut Creek: The Walnut Creek area encompasses the stream; numerous ponds;
disposal areas including an active landfill, disposal trenches, and surface
impoundments; and former waste storage areas. The drainage basin receives surface
water flows and groundwater seepage from contaminated and active industrial areas of the site,
which potentially could affect down stream surface water supplies. A work plan for an
investigation was submitted and approved. Field work began in late 1992 and has been completed
for the first phase of investigation.
Present Landfill: This area of the site comprises a large, active landfill that has been
in use for over 20 years. It once was enclosed by a groundwater diversion and
seepage collection system, but the system has since been abandoned and is partially
destroyed. DOE is expected to propose an interim cleanup action detailing the presumptive
remedy for the landfill.
Original Process Waste Lines: This area consists of an underground network of
old process waste lines that were used to pipe wastes to the surface impoundments or
discharge points. A preliminary work plan for an investigation of these poorly mapped
lines was submitted and has been approved. Field work was delayed, but the investigation is
expected to be completed in mid-1996.
Low Priority Areas: Because levels of contamination at the low priority areas were
found to be within established health standards, no further action is anticipated at
these areas.
Other Areas: Eight separate investigations will be conducted to determine the nature
and extent of contamination. These areas include the 700 Area, Other Outside
Closures, West Spray Field, 400/800 Area, 100 Area, Radioactive Sites, and Inside
Building Closures. Investigations are in various stages of development for these areas.
ROCKY FLATS PLANT (USDOE) 3 April 1995
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Site Facts: In January 1991, the EPA, the DOE, and the State signed a Rocky Flats Interagency
Agreement (IAG) to guide environmental restoration at the site under the Comprehensive
Environmental Response Compensation and Liability Act (CERCLA), and the Resource
Conservation and Recovery Act (RCRA). The State also issued DOE a RCRA permit for
handling hazardous wastes, incorporating all the substantive requirements of the IAG. In May
1991, a Federal Facility Compliance Agreement was signed to achieve compliance with land
disposal restrictions. In May 1992, an amendment was signed extending the provisions of the
Federal Facility Compliance Agreement to include "Third Third" Mixed Wastes. In May 1993,
this Federal Facility Compliance Agreement was terminated in anticipation of a State lead
agreement. In light of the change in mission at Rocky Flats, the EPA, the DOE, and the State
began negotiations in March 1994 for a new Rocky Flats Cleanup Agreement, intended to replace
the existing IAG. The parties anticipate that the Rocky Flats Cleanup Agreement will broaden
the scope of cleanup to include decontamination and decommissioning of buildings and to ensure
that implementation problems being experienced in the existing IAG will not occur again. The
parties also anticipate that the Rocky Flats Cleanup Agreement will result in overall cost savings
through increased cooperation between DOE and the regulators, and through DOE initiatives to
streamline many of its internal procedures. To evaluate reuse of its facilities, DOE has initiated
the National Conversion Pilot Project (NCPP) at Rocky Flats. The mission of the NCPP is to
"explore and demonstrate, at the Rocky Flats site, the feasibility of economic conversion at
Department of Energy facilities." Under this program, a private company, Manufacturing
Sciences Corporation, has proposed to use four Rocky Flats buildings, equipment, and up to 500
displaced or potentially displaced workers to recycle scrap metals (including depleted uranium
and beryllium) into a variety of waste containers for DOE using environmentally-conscious
manufacturing methods. A comprehensive public involvement program will ensure the
participation of stakeholders.
Environmental Progress
Numerous actions and investigations currently are underway at the Rocky Flats Plant. The
cleanup of contaminated groundwater resources at the site has begun, and further cleanup
activities are planned that will eliminate the potential for exposure to hazardous substances at
diverse areas of the site.
April 1995 4 ROCKY FLATS PLANT (USDOE)
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ROCKY MO
ARSENAL
COLORADO
EPA ID# CO5210020765
Site Description
EPA REGION 8
Adams County
KXniles northeast of downtown Denver
Other Names:
Shell Chemical Company
Shell OH Company
The 17,000-acre Rocky Mountain Arsenal site is a facility owned and operated by the U.S.
Army. Hazardous wastes have been deposited on about 1,750 acres of the site. The facility
was established in 1942 and has been used by both government and industry to manufacture,
test, package, and dispose of various chemical products, chemical warfare agents, and
munitions, including rocket fuels, herbicides, pesticides, nerve gases, mustards, and incendiary
munitions. In 1947, portions of the site were leased to a chemical manufacturing company,
Colorado Fuel and Iron Corporation, for the manufacture of chlorinated benzenes and the
pesticide DDT. Shell Chemical Company later assumed the pesticide and herbicide
manufacturing operations. Munitions and pesticide operations over 40 years led to spills and
the disposal of more than 750 different hazardous wastes in several areas. Industrial
effluents routinely were discharged to unlined evaporation basins. Solid wastes, including
munitions, were buried at various locations. Spills of raw materials and final products
occurred within the manufacturing complexes. All production operations ceased in 1982.
Investigations by the Army have identified at least 178 on-post areas as being potentially
contaminated with hazardous wastes. Basin F, which is closed, formerly held as much as 240
million gallons of liquid wastes. In 1988, the 10.5 million gallons of Basin F liquids which
remained were then stored in three lined tanks and a double-lined surface impoundment. An
incinerator operated between March 1993 and July 1995 successfully destroyed the
contaminated liquid. 564,000 cubic yards of Basin F solids are in a double-lined, capped
waste pile. Five unlined basins received wastes before Basin F was built. The site also
contains two major industrial complexes that produced the pesticides, nerve gas, and mustard
gas. Shallow groundwater is contaminated, as is the deeper aquifer to a much less extent.
353 abandoned wells have been plugged. Seven groundwater intercept systems - and an
eighth system north of the Arsenal - have been installed to remove shallow aquifer
contaminants and treat one billion gallons of water a year. Three plumes of contaminated
groundwater migrated off site before the intercept systems were installed, with one eventually
near the South Platte River at very low levels. A surface stream offpost receives some
contaminants from ground water discharge. The South Adams County Water and Sanitation
District (SACWSD), created in 1953, supplies approximately 30,000 customers with treated
water; its state-of-the-art water treatment system was constructed with Army and EPA funds.
Two environmental justice communities are adjacent to the site. Community involvement is
intensive. Final remedies for the contaminated soils, structures, and groundwater will be
selected in 1996.
Site
Responsibility:
This site is being cleaned up through
actions of Federal, State, and
potentially responsible parties.
NPL LISTING HISTORY
Proposed Date: 10/15/84
Final Date: 07/22/87
ROCKY MOUNTAIN ARSENAL
August 1995
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Site Facts: In 1982, the EPA initiated a Memorandum of Agreement (MOA) with the
Army, the State, and Shell Chemical Company, a potentially responsible party, requiring the
exchange of information and participation in the development and implementation of
response actions at the Arsenal. In 1989, Shell, the Army, the Department of Interior, the
Agency for Toxic Substances and Disease Registry, the Department of Justice, and the EPA
signed a Federal Facility Agreement. The new agreement superseded the MOA, apportioned
liability between Shell and the Army, established several initial remediation actions, and
resolved the Army-Shell litigation. In 1992 Congress passed legislation to make the Arsenal a
National Wildlife Refuge after EPA certifies that the cleanup is complete. The U.S. Fish and
Wildlife Service manages the wildlife and habitat at the Arsenal. After lengthy litigation
against the U.S., the State of Colorado established its RCRA authority for at least Basin F.
Environmental Progress
Several initial remediation actions have been performed, as described below. The end of
production, some initial remediation actions, the provision of alternative water supplies, and
onpost access restrictions have reduced the potential for exposure to contamination.
CERCLA studies and further cleanup actions are being performed. Further reduction of
potential exposure threats and selection and prompt implementation of final remedies are top
priorities.
Threats and Contaminants
Groundwater is contaminated with various volatile organic compounds (VOCs),
pesticides, heavy metals, and products from warfare agents. Sediments from lakes
and drainage areas are contaminated with heavy metals and pesticide residuals.
Soils are contaminated with heavy metals including arsenic, lead, and mercury;
pesticides, and VOCs. The health threats associated with this site include inhaling
contaminated dust and touching or ingesting contaminated soils. No one lives
onpost, but the many affected homes nearby have been hooked to a water
treatment system or provided bottled water.
Cleanup Approach
This site is being managed in stages: many initial actions and long-term remedial phases
focus on the contamination. After extensive public involvement on remedy options, in June
1995 the parties negotiated a conceptual remedy for all onpost and offpost issues. That
concept will be the preferred alternative in the Onpost Proposed Plan. After consideration of
formal public comment, the Onpost ROD is expected in spring 1996. The Offpost ROD is
expected in fall 1995. The initial actions described below must be consistent with the final
remedy and included in those RODs.
August 1995 2 ROCKY MOUNTAIN ARSENAL
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Site Contamination: Offpost and onpost studies investigated the nature and extent
of contamination, plus alternatives for final cleanup.
Response Action Status
Earliest Initial Actions: The Army installed the North Boundary Groundwater
Treatment System in stages between 1979 and 1982. Shell Oil Company installed
the Irondale Groundwater Treatment System in 1981. The contaminated sewer
connected to Basin F was removed in 1982. In 1984, the Northwest Boundary Groundwater
Treatment System was completed. Over 76,000 drums of waste salts were removed in 1986.
A 12,045-foot-deep hazardous waste injection well was closed in 1986. Later initial actions
are described below.
South Adams County Public Water Supply: In 1986, the EPA connected
approximately 400 private drinking water wells to a temporary granular activated
carbon water treatment system which was newly supplying water to 30,000 people
served by SACWSD. A permanent water treatment system began operating in 1989 as the
Klein Water Treatment Plant. Further remediation is part of the preferred remedy for the
pending Onpost and Offpost RODs.
Basin F and Basin A Groundwater, and Hydrazine Facility: Groundwater
Intercept and Treatment Systems North of Basin F and at Basin A Neck are in
operation; final remedies are pending. Destruction of 300,000 gallons of liquid
wastes at the hydrazine facility, and cleanup/dismantling of that facility, plus closure of the
sanitary sewer, have been completed. Reapplication of wind-blown dust control occurs every
2 to 3 years. Massive asbestos removal continues since 1989.
South Tank Farm Plume: This plume is monitored for possible plume
movement and natural biodegradation. The final remedy will be part of the 1996
Onpost ROD.
Offpost Groundwater Intercept and Treatment System: This groundwater
system, north of the Arsenal, began operation in 1992 and will be part of the 1995
Offpost ROD.
Abandoned Wells: A total of 353 abandoned wells onpost were sampled, closed,
and plugged in 1990, to prevent their potential to channel contamination to lower
aquifers.
Basin F Liquids and Sludges: Basin F was closed in 1989. Approx. 10.5
million gallons of liquid and 564,000 cubic yards of contaminated sludges were
removed to temporary storage. The final remedy for sludges will be in the 1996
Onpost ROD.
ROCKY MOUNTAIN ARSENAL 3 August 1995
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Basin F Liquids: A "submerged quench incinerator" (SQI) was constructed in
1991-3 to treat the liquids; it operated between 3/93 and 7/95. Metals in
incineration residues were recycled offsite, then the resulting safe liquids were
discharged.
Contaminated Liquids in the Building 1727 Sump: Treatment of the sump
liquids continued through 1993.
Wastewater: Operation of a treatment plant for wastewater resulting from other
cleanup actions began in late 1992.
M-1 Ponds, Lime Basins, Motor Pool, and Rail Yard: A vitrification system
selected for the Ml Ponds was cancelled. Since 1992, operation and maintenance
are ongoing for the Motor Pool Area vapor extraction system, the Lime Basins
containment system, and the Rail Yard groundwater intercept and treatment system. Final
remedies will come in 1996.
Army Trenches: A monitoring program is ongoing, with annual re-evaluation to
determine if further action is necessary. The final remedy will be in the 1996
ROD.
Shell Trenches: Construction of the temporary containment system, which
consists of a slurry wall and cap, was completed in 1991. The 1996 ROD will have
the final remedy.
Chemical Process Related Equipment: Decontamination of the production
era equipment, piping, and containers began in 1992 and continues, much is
recycled.
Contaminated Soils and Structures: Massive contamination remains, such as
in Basin A and the South Plants. In the fall of 1995, a Proposed Plan will present
for formal public comment the June 1995 negotiated preferred remedy. The
Onpost ROD is expected in 1996.
Adjacent NPL Sites: The investigation determining the nature and extent of
contamination of an offpost area, south of 86th Avenue, affecting the SACWSD,
continues under the jurisdiction of the Chemical Sales Company NPL Site. Two
other NPL sites and other sources of ground water contamination are south and southwest of
RMA.
August 1995 4 ROCKY MOUNTAIN ARSENAL
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Site Repository
Joint Administrative Document Facility (JARDF)
Room 14, Arsenal Security Building
72nd and Quebec Streets, Commerce City CO 80022
(303) 289-0362
For EPA answers to questions about the Arsenal, call Mr. Pete Peterson, Community
Relations Coordinator at EPA, (303) 294-1130, or Mr. Michael Holmes, (303) 294-1141.
ROCKY MOUNTAIN ARSENAL
August 1995
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SAND CREEK
INDUSTRIAL
COLORADO
EPA ID# COD98071795
EPA REGION 8
Adams County
Commerce City
Other Names:
L C Corporation
ado Organic Chemical Company
Holly & 48th St. Landfill
Browning Ferris/Globe Chemical
Colorado International Corporation
Private Brands Western, Inc.
Site Description
The 550-acre Sand Creek Industrial site consists of four known sources of contamination, all of
which are currently inactive: the Oriental Refinery, the Colorado Organic Chemical property, the
L.C. Corporation acid pits, and the 48th Street and Holly Landfill. The site's 25-year history
includes a fire that destroyed the refinery, a major spill of refined petroleum, two methane
explosions which killed two men and injured others, an incident in which livestock were severely
burned when they wandered into acid pits, and a fire at the pesticide formulator that released
fumes over northeast Denver and resulted in several firemen being hospitalized. The Oriental
Refinery is a former oil refinery and consists mostly of rubble. The site is now occupied by a
propane distributing firm and a gas station. The Colorado Organic Chemical plant originally
manufactured pesticides in the 1960s. Since 1968, when a fire destroyed three of the buildings
on site, several health agencies have found unacceptable conditions at the plant. These conditions
have included unsatisfactory waste management practices and worker safety conditions, violations
in storage and handling of flammable liquids, and soil containing high levels of pesticides and
other chemicals. A second fire occurred at the plant in 1977. The L.C. Corporation hauled and
disposed of approximately 8,000 tons of acid waste in pits. Lime was added to neutralize the
acid and the pit area was covered. Acid was found to be seeping from the pits into Sand Creek
in 1976. In 1980, L.C. Corporation covered the seepage with clean soil. The 48th Street and
Holly Landfill was used to dispose of municipal wastes. In 1991, a methane gas collection system
was constructed to address contamination at the landfill. Fewer than 25 people live within 1/2
mile of the site; however, hundreds of people work in the area.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 12/30/82
Final Date: 09/08/83
Threats and Contaminants
The EPA conducted sampling at the site and found the soil and groundwater to be
contaminated with volatile organic compounds (VOCs), pesticides, herbicides, and
arsenic. People who accidentally touch or ingest contaminated groundwater or soil
may suffer adverse health effects. In addition, people on site may be exposed by
inhaling contaminated dust or vapors from the soil.
April 1995
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Cleanup Approach
Response Action Status
Initial Actions: In 1984, Colorado Organic Chemical removed waste drums and
contaminated soil and fenced the area. In 1988, the EPA removed two tanks and
five drums containing pesticides and solvents and transported them to federally-
approved facilities. In addition, a synthetic cover was placed over the contaminated soil to
prevent erosion and vapor emissions. In 1991 and 1992, the potentially responsible parties
installed a methane gas extraction and treatment system at the 48th and Holly Landfill. This
system has proven to be very effective in burning off gas and hazardous substances that are
produced by decaying trash.
Colorado Organic Chemical Subsurface Soils and Structures: Cleanup
activities began in 1990 with the demolition of contaminated tanks and buildings and
the disposal of the debris and tank waste at a federally-approved facility. In 1993, an
amendment to the 1989 remedy was approved to change the selected remedy for the surface soils
from soil washing to low temperature thermal treatment (LTTT). LTTT is roughly half the cost
of soil washing, and the soils are cleaner after processing through the LTTT system. LTTT
heats the soil in a dryer to drive off the soil gas and VOCs. Cleanup of the Colorado Organic
Chemical contamination in the surface soils, using LTTT, began in the spring 1994 and continued
for approximately 6 months. After being processed, the 8,000 cubic yards of on-site soils treated
in the LTTT were backfilled on-site. In addition to the LTTT treatment of the surface soils, the
deeper soils are being cleaned by soil vapor extraction. The soil vapor extraction process began
at the site in 1993 and was completed in mid-1994. Over 150 tons of contamination were
extracted (vacuumed) from the deeper soils with this process.
L.C. Corporation Acids Pits: The acid contamination in the pits and surrounding
soils is being addressed as a result of the fire of 1977. Prior to EPA action, the L.C.
Corporation hauled and disposed of acid waste in pits, neutralized the acid and pit
area with lime, and covered the seepage with clean soil. After completing its investigation of the
acid pits, the EPA determined in 1993 that no additional action was required in this area.
48th Street and Holly Landfill: In 1992, an investigation was conducted to
determine the extent of contamination and the risk associated with the contamination
from the landfill. In 1992 and early 1993, a feasibility study was prepared to identify
and evaluate alternative remedies for landfill contamination. The remedy was selected in early
1993, which includes continued operation of the landfill gas extraction system, installed in 1991
as a result of a fire, maintenance of surrounding fencing and landfill cap, and groundwater
monitoring. The construction of the remedy was completed in 1994, and monitoring is expected
to continue for another 10 to 20 years.
April 1995 2 SAND CREEK INDUSTRIAL
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Groundwater: In 1993, the EPA completed extensive studies of the groundwater in
the area to better determine the extent of groundwater contamination. A remedy was
selected in the spring of 1994. EPA prepared the design for groundwater monitoring
and partial removal of the light non aqueous phase liquid (LNAPL) that is floating on top of
groundwater in two localized areas. This LNAPL was removed by soil vapor extraction/dual
vapor extraction in 1994. Quarterly long-term groundwater monitoring will continue to ensure the
effectiveness of the remedy.
Site Facts: There is a new building being constructed on the site which is considered
"Brownfields Redevelopment" in action. Brownfields Redevelopment saves pristine "greenfields"
from development by putting previously contaminated properties back into industrial land use.
Environmental Progress
The construction of all remedies has been completed. The removal of drums and contaminated
soil and the fencing of the area, as well as ongoing groundwater and soil treatment, has reduced
the potential for exposure to contaminated materials at the Sand Creek Industrial site while
cleanup activities are being completed.
SAND CREEK INDUSTRIAL
April 1995
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SMELTERTO
SITE
COLORADO
EPA ID# COD98376973
EPA REGION 8
Chaffee County
Near Salida
Site Description
The Smeltertown site is located in a rural area northwest of Salida, Colorado on the eastern bank
of the Arkansas River. The site encompasses 120 acres and has been impacted by three different
industrial activities: smelting; woodtreating; and zinc sulfate manufacturing. A lead/zinc smelter
was operated from the turn of the century until about 1920 on the site. During this period, hot
slag was dumped along the banks of the Arkansas River. The slag still lines the eastern bank of
the river. The smelter smokestack has been placed on the National Register of Historic Places.
Beginning in 1925, wood treatment occurred at this site. Railroad ties and other lumber products
were treated with creosote and possibly pentachlorophenol (PCP). These chemicals were allowed
to drip on the ground after the lumber was treated. Creosote-contaminated soils were removed
from the site in 1986 and 1992. The CoZinCo facility presently manufactures a zinc sulfate
monohydrate by treating galvanizing wastes with sulfuric acid. Localized areas of contamination
include several drum piles, sludge disposal and storage areas, and two waste water lagoons.
These sources of contamination are being addressed under a corrective action order issued by the
State of Colorado.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 02/07/92
Threats and Contaminants
Contaminated soils and slag associated with the smelter operations contain elevated
levels of arsenic, cadmium, copper, lead, manganese, and zinc. Soil is also
contaminated with creosote and PCP from wood treatment. Groundwater is
contaminated with zinc.
Cleanup Approach
This site is being addressed in four stages: initial actions and three long-term remedial phases
focusing on cleanup of the smelter, wood treatment, and CoZinCo areas.
March 1995
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Response Action Status
address contamination.
Initial Actions: In 1993, several houses were provided bottled water in response to
zinc contamination in residential wells. Soils contaminated with lead and creosote
were removed from several residences.
Smelter: The EPA completed its investigation of contamination derived from the
historic smelter operations in the fall of 1994. Based on the results of the
investigation, the EPA is planning to select a cleanup remedy in 1995.
Wood Treatment: Beazer East, Inc. has begun a study to investigate the extent of
contamination from the historic wood treating operations. The investigation is
scheduled to be completed in 1995, at which time a remedy will be selected to
CoZinCo: An investigation into the nature and extent of contamination at the
CoZinCo facility is underway and expected to be completed in 1995.
Environmental Progress
Providing bottled water to affected residences and removing contaminated soils have reduced the
threat to human health and the environment while investigations continue and cleanup activities
are planned.
Site Repository
Town of Salida Public Library
March 1995
SMELTERTOWN SITE
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SMUGGLER
MOUNTAIN
COLORADO
EPA ID# COD98080627
EPA REGION 8
Pitkin County
_ IfLjthe northeast corner of the City of
Aspen
Site Description
The 116-acre Smuggler Mountain site is an inactive silver and lead mining site that was in
operation from 1879 to 1918. Waste rock and mine tailings from mills and mines in the area
have been deposited between the Roaring Fork River and the steep slope that forms the western
side of Smuggler Mountain. Most of the mines are abandoned, but limited mineral exploration
activities are still conducted on site. Tailings and mine wastes were mixed with native soil, and
spread across the site. The total volume of mine waste material has been estimated at 1,300,000
cubic yards. In many cases, development in the Aspen area has taken place directly over waste
piles, or mine waste has been dozed into mounds that remain as berms of contaminated soil.
Contaminated soil has also been used as fill material in some areas. The site is situated in a
residential area in the northeastern portion of the City of Aspen. The City has a year-round
population of approximately 4,500, as well as a substantial number of seasonal visitors. The City
of Aspen obtains its drinking water from the Roaring Fork River, approximately 1,000 feet
downstream from the site.
Site Responsibility:
The site is being cleaned up through
Federal, State and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 10/15/84
Final Date: 06/01/86
Threats and Contaminants
Soil is contaminated with heavy metals including lead, cadmium, and arsenic. The
potential health threats to area residents include accidentally ingesting contaminated
surface soils or eating vegetables grown in contaminated soils. The Roaring Fork River
is not contaminated by the site, and thus is not considered a potential health risk to the
residents of Aspen.
March 1995
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Cleanup Approach
This site is being addressed in three stages: immediate actions and two long-term remedial phases
focusing on cleanup of the residential areas and cleanup of the mine area.
Response Action Status
Immediate Actions: In 1985, a party potentially responsible for site contamination
installed fencing around portions of the site and posted warning signs, as directed by
the EPA. In 1990, EPA excavated, recontoured, and capped contaminated soil on
two residential properties as a demonstration project.
Residential Areas: The remedy selected by EPA in 1993 was based on the
recommendations of the Technical Advisory Committee and includes: capping and
revegetating the highly contaminated berm area; covering, revegetating, and
monitoring the common-use areas of exposed mine waste, including the Mollie Gibson Park;
implementing a blood-lead surveillance program for young children using the Pitkin County
Health Department; planting vegetable gardens in at least 12 inches of clean soil; and using the
Aspen/Pitkin Environmental Health Department to evaluate site construction projects or land use
changes to determine whether they present a threat of soil exposure to young children. The EPA
will make a final determination regarding cleanup of residential soils based on the review of lead
speciation studies that have been completed, on-going bioavailability studies, and results of the
Pitkin County Health Department's blood lead and dust monitoring program. Cleanup activities
are expected to be completed in late 1995.
Mine Area: The EPA is currently conducting an environmental engineering/cost
evaluation to examine alternatives for addressing contamination in the mine area. The
evaluation is expected to be completed in early 1996.
Site Facts: In 1985, the EPA issued three Administrative Orders to the potentially responsible
parties. The orders required the property owners to notify the EPA of any plans to move soils or
mining wastes on the site, to investigate site contamination, to recommend alternatives for final
cleanup, and to provide for the fencing and securing of a portion of the site to prevent public
access.
Environmental Progress
Initial actions such as fencing portions of the site and excavating, removing, and capping
contaminated soil in other areas have reduced the threat of direct contact with contaminants while
additional cleanup activities are being planned.
March 1995 2 SMUGGLER MOUNTAIN
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SUMMITVILLI
COLORADO
EPA ID# COD983778432
EPA REGION 8
Rio Grande County
Del Norte
Site Description
The Summitville mine site is located in the San Juan Mountains of Colorado. The site, which
covers 1,400 acres, is extremely remote, located at an elevation of over 11,000 feet above sea
level, and usually accessible by vehicle only during the summer months. Mining operations
began at the site in the late 1800s. In 1986, the most recent operator, Summitville Consolidated
Mining Corp. Inc. (SCMCI) began open-pit mining and gold recovery operations through cyanide
heap leaching. SCMCI originally designed the mining operation as a non-discharging wastewater
facility. However, problems with discharges eventually compelled SCMCI to obtain a National
Pollutant Discharge Elimination System (NPDES) permit from the State to operate a wastewater
treatment plant. Throughout operations, several releases of water contaminated with cyanide and
metals have occurred. The State has issued Notices of Violation to SCMCI for the unpermitted
releases of contaminated water.
Site Responsibility:
The site is being addressed through
Federal and State actions.
NPL LISTING HISTORY
Proposed Date: 05/10/93
Final Date: 05/31/94
Threats and Contaminants
Several releases of water contaminated with cyanide and metals have been documented.
In the past, fish kills have been reported from Wightman Fork to the Terrace
Reservoir, approximately 20 miles downstream from the site.
Cleanup Approach
This site is being addressed in four stages: initial actions and interim actions focusing on cleanup
of the Cropsy Waste Pile and Beaver Mud Dump, the Heap Leach Pad, and the South Mountain
and Minesite Reclamation areas.
April 1995
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Response Action Status
Initial Actions: The EPA currently is maintaining the site to ensure that 150 million
gallons of contaminated water are not released into Wightman Fork, a tributary to the
Alamosa River. This includes year-round operation of three retrofitted water
treatment plants to reduce contaminant levels in the water prior to its release from the site, or its
use in stabilization activities. A time critical removal action was initiated in September 1993.
During this action, the system which drains water from the historic underground mine workings
was plugged. This action has flooded the mine workings and is expected to reduce production of
the acidic, metal-contaminated water. This action is expected to be completed in 1995. In
September 1993, a non-time critical removal action was initiated at the site to address the four
areas primarily responsible for the generation of acid mine drainage: the Cropsy Waste Pile
(CWP); Beaver Mud Dump; Summitville Dam Impoundment; and the Mine Pits. The response
action was segregated into three phases, with each phase to be completed in a single construction
season. The first phase moved approximately 1 million cubic yards of the CWP to the Mine Pits
and was completed in early 1994. Phase II was initiated in the late summer of 1994 and removed
the remainder of the CWP to the Mine Pits and excavated the tailings from the Summitville Dam
Impoundment. Phase II was completed in early 1995 and included excavation of approximately
2l/2 million cubic yards of tailings. This action will further reduce the volume of contaminants
generated from the site. The preliminary baseline ecological risk assessment is being conducted
and is expected to be completed in 1995.
Cropsy Waste Pile and Beaver Mud Dump: After an investigation into the
nature and extent of contamination at these areas, the EPA proposed to continue the
Cropsy work and water treatment begun under the initial actions with little change in
scope or direction. During the final phase of the CWP response action, the remainder of the
waste will be placed in the Mine Pits. A cap will be built over the waste placed in the Mine Pits
that will reduce infiltration of water into the waste material and existing underground workings.
Design of this interim remedy was begun in the fall of 1994 and is expected to be completed in
1995.
Heap Leach Pad: An investigation conducted by the EPA called for the
detoxification and closure of the heap leach pad. Of the cleanup alternatives
identified, it was determined that biotreatment to destroy the cyanide, accompanied
with dewatering of the heap, followed by contouring and capping, provided the best overall long-
term protection of human health and the environment. Design of these activities began in the fall
of 1994 and is expected to be completed in 1995.
South Mountain and Mine Reclamation: Because Summitville is located in a
remote location, cleanup alternatives are limited. Consideration of standard
reclamation practices for mining sites also indicated that the most economic
alternative for site reclamation would be revegetation, which uses on-site topsoil. Unfortunately,
the on-site topsoil is in poor condition and will require careful management to establish adequate
growth under the harsh Summitville climate. A decision on the final approach to stabilizing and
controlling the erosion and the generation of acid mine drainage is expected in 1995.
April 1995 2 SUMMITVILLE MINE
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Site Facts: The State of Colorado has issued several Notices of Violation to SCMCI. In 1992
SCMCI declared bankruptcy. As a result, the EPA has maintained the site using Superfund
emergency funds.
Environmental Progress
The EPA is maintaining the site to ensure that no accidental releases of contaminated water occur
while cleanup activities are planned.
Site Repository
Del Norte Public Library
790 Grand Avenue
Del Norte, CO 81132
Conejos County ASCS Office
15 Spruce Street, Box 255
LaJara, CO 81140
U.S. EPA
Superfund Records Center
999 18th Street, Suite 500
Denver, CO 80202-2466
SUMMITVILLE MINE
April 1995
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URAVAN URA
PROJECT (UN
CARBIDE)
COLORADO
EPA ID# COD007063274
Site Description
PEPA REGION 8
Montrose County
90 miles southwest
of Grand Junction
Other Names:
Lkavdn Uranium Milt Operations
Uravan Uranium Mill Town
UMETCO
The Uravan Uranium Project site began as a radium recovery plant in 1915. The plant was
expanded to include vanadium recovery in 1935 and began this process in 1936. The plant
operated from the late 1940s as a uranium processing facility. In 1984, Union Carbide formed a
wholly-owned subsidiary, UMETCO, which operated the facility until it was closed. During the
history of operations at the site, a large volume of waste products, including raffinates (liquid
wastes from the uranium processing operations), mine tailings, and raffinate crystals from the
various processes were disposed of on site. Radon gas emanates from the eroding tailings piles.
Uravan is one of the more complex radiation sites in the country, with heavy metals, residual
salts, and radionuclide contamination of ground water and surface water. The Town of Uravan
was established in 1935 to house the workers at the mill and mine facilities; the town no longer
exists.
Site Responsibility:
This site is being addressed through
Federal, State, and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 10/15/84
Final Date: 06/10/86
Threats and Contaminants
Air at the site contains elevated levels of radon gas. Soil, groundwater, and the San
Miguel River contain radionuclides and heavy metals. Before the town was evacuated
and torn down, potential exposure to radionuclides posed a threat to human health.
Cleanup Approach
This site is being addressed in a long-term remedial phase focusing on cleanup of the entire site.
April 1995
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Response Action Status
Entire Site: The State completed a plan to clean up contamination at the site in 1986,
and reached an agreement with Union Carbide regarding their performance of the
cleanup actions. The remedy includes: reclaiming nearly 10 million cubic yards of
radioactive tailings by capping and revegetation; building a disposal system for radioactive
crystals; placing IVi million cubic yards of waste found along the San Miguel River hi a secure
disposal area; excavating contaminated soil and placing it in an approved landfill; and reclaiming
and revegetating the land on the site. Most of the 10 million cubic yards of tailings have been
placed in a secured disposal area and capped. Process pond water and seep water now are
collected and evaporated in lined ponds. Approximately 400,000 cubic yards of pond crystals
have been deposited in a clay-lined repository. Union Carbide has finished building two lined
evaporation ponds adjacent to the State highway. The State installed pumps and is pumping the
old, unlined tailings ponds for mill raffinate and sending the recovered wastewater to the new
lined ponds. The State also is conducting radiation surveys of the old pond area to address issues
that affect the health of workers on site before they dewater the raffinate crystals from the old
ponds. The major elements of these activities are underway, and construction is scheduled to be
completed by 1995, although the entire site cleanup will not be completed until after the year
2000.
Site Facts: The EPA entered into a Memorandum of Agreement (MOA) with the State in 1986
to avoid duplicating efforts. The MOA designated the State as the acting lead agency and
required the State to consult with the EPA on all actions taken at the site. The MOA also
provides for effective remedies to address site contamination. Although the cleanup activities
have not been completed, the EPA conducted a five-year review in June 1994 to ensure the
effectiveness of the remedies implemented thus far. UMETCO also has applied to the State for a
permit to turn the site into a depository for off-site radioactive waste.
Environmental Progress
After adding this site to the NPL, the EPA performed preliminary investigations and determined
that, because the town surrounding the site has been evacuated and torn down, no immediate
actions were required at the Uravan Uranium site. Cleanup actions presently completed or
underway will ensure the protectiveness of human health and the surrounding environment. The
EPA's five-year review concluded that the cleanup is making excellent progress and that clean up
standards are being achieved.
Site Repository
Colorado State Health Department, Radiation Control Division, 3773 Cherry Creek Drive North,
Denver, CO 80231
April 1995 2 URAVAN URANIUM PROJECT
(UNION CARBIDE CORP.)
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WOODBURY
CHEMICAL
COLORADO
EPA ID# COD98066707
EPA REGION 8
Adams County
Commerce City
Site Description
The 11-acre Woodbury Chemical Company site began operations in the 1950s as a pesticide
formulation plant. The plant burned down in 1965, and the fire debris and rubble, including
water-soaked bags of pesticides and contaminated soils, were moved to an adjacent lot. Over
1,500 pounds of pesticides were placed on the lot. The plant was rebuilt in the original location
and continued operations until 1971. Various pesticides and volatile organic chemicals (VOCs)
were produced or used on the site during its period of operation. The site is surrounded by
industry, and approximately 3,000 people live within lh. mile of the site. Cleanup of the entire
site was completed in mid-1992, and the site was deleted from the NPL in early 1993.
Site Responsibility:
This site was addressed through Federal
and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 07/23/82
Final Date: 09/08/83
Deleted: 3/22/93
Threats and Contaminants
Sediments in a drainage ditch, surface water runoff, and soils on the site contained
chlorinated pesticides and heavy metals. Prior to cleanup actions, potential health risks
existed for individuals accidentally ingesting or touching contaminated soils or surface
water.
Cleanup Approach
Response Action Status
Immediate Actions: In 1983, to prevent public access to the site and to help
stabilize the contamination, the EPA posted warning signs, installed a fence around
the site, and graded the site to prevent additional surface water runoff.
April 1995
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Rubble Piles: In 1985, the EPA selected a cleanup remedy for the area that involved
a combination of off-site landfilling and incineration of soil and rubble. During
design of this remedy in 1986, the EPA discovered that site contamination extended
farther off site than was originally identified. This led to the addition of another cleanup area to
the site, which was addressed in the next phase of the cleanup (see below). All contamination
associated with the rubble was removed from the site by mid-1992.
Soils: In 1989, the EPA selected a remedy for cleanup of the remainder of the site,
which included off-site incineration of up to 2,000 cubic yards of highly contaminated
soils and placement of 10,600 cubic yards of soils above the cleanup levels in an
off-site, EPA-approved landfill. The design of the remedies began in 1990 and was completed in
mid-1991. This work was conducted by the parties potentially responsible for the contamination,
under EPA supervision. Cleanup of the site began in 1991 and was completed in mid-1992.
Site Facts: An Administrative Order on Consent was signed in 1987 between the EPA and the
McKesson Corporation for the company to conduct an investigation into the contamination at the
site and to identify alternative remedies for the cleanup. A Consent Decree was signed in 1990
between the EPA, McKesson Corporation, and Farmland Industries. This decree provided for
the cleanup and recovery of past costs associated with the site study and cleanup design. A
separate Consent Decree was completed in 1991 between the EPA and Maytag that provided for
recovery of a portion of the past costs.
Environmental Progress
Cleanup of the entire site was completed in mid-1992. Contaminant concentrations throughout
the site have been reduced to health-based levels for residential use. The site was deleted from
the NPL on March 22, 1993.
April 1995 2 WOODBURY CHEMICAL COMPANY
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