EPA/540/4-90/007
September 1990
NATIONAL PRIORITIES LIST SITES:
Colorado
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
Office of Emergency & Remedial Response
Office of Program Management
Washington, D.C. 20460
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If you wish to purchase copies of any additional State volumes or the National
Overview volume, Superfund: Focusing on the Nation at Large, contact:
National Technical Information Service (NTIS)
U.S. Department of Commerce
5285 Port Royal Road
Springfield, VA 22161
(703) 487-4600
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PAGE
INTRODUCTION:
A Brief Overview . iii
SUPERFUND:
How Does the Program Work to Clean Up Sites vii
How To:
Using the State Volume xvii
NPL SITES:
A State Overview xxi
THE NPL PROGRESS REPORT xxiii
NPL: Site Fact Sheets 1
GLOSSARY:
Terms Used in the Fact Sheets G-1
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11
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WHY THE SUPERFUND
PROGRAM?
As the 1970s came to a
-" close, a series of head-
% line stories gave
Americans a look at the
dangers of dumping indus-
trial and urban wastes on the
land. First there was New
York's Love Canal. Hazard-
ous waste buried there over a
25-year period contaminated
streams and soil, and endan-
gered the health of nearby
residents. The result: evacu-
ation of several hundred
people. Then the leaking
barrels at the Valley of the
Drums in Kentucky attracted
public attention, as did the
dioxin tainted land and water
in Times Beach, Missouri.
In all these cases, human
health and the environment
were threatened, lives were
disrupted, property values
depreciated. It became in-
creasingly clear that there
were large numbers of serious
hazardous waste problems
that were falling through the
cracks of existing environ-
mental laws. The magnitude
of these emerging problems
moved Congress to enact the
Comprehensive Environ-
mental Response, Compensa-
tion, and Liability Act in 1980.
CERCLA — commonly
known as the Superfund —
was the first Federal law
established to deal with the
dangers posed by the
Nation's hazardous waste
sites.
After Discovery, the Problem
Intensified
Few realized the size of the
problem until EPA began the
process of site discovery and
site evaluation. Not hun-
dreds, but thousands of
potential hazardous waste
sites existed, and they pre-
sented the Nation with some
of the most complex pollution
problems it had ever faced.
In the 10 years since the
Superfund program began,
hazardous waste has surfaced
as a major environmental
concern in every part of the
United States. It wasn't just
the land that was contami-
nated by past disposal prac-
tices. Chemicals in the soil
were spreading into the
groundwater (a source of
drinking water for many) and
into streams, lakes, bays, and
wetlands. Toxic vapors
contaminated the air at some
sites, while at others improp-
erly disposed or stored
wastes threatened the health
of the surrounding commu-
nity and the environment.
EPA Identified More than
1,200 Serious Sites
EPA has identified 1,236
hazardous waste sites as the
most serious in the Nation.
These sites comprise the
''National Priorities List":
sites targeted for cleanup
under the Superfund. But site
discoveries continue, and
EPA estimates that, while
some will be deleted after
lengthy cleanups, this list,
commonly called the NPL,
will continue to grow by ap-
proximately 100 sites per
year, reaching 2,100 sites by
the year 2000.
THE NATIONAL
CLEANUP EFFORT IS
MUCH MORE THAN
THE NPL
From the beginning of the
program, Congress recog-
nized that the Federal govern-
ment could not and should
not address all environmental
problems stemming from past
disposal practices. Therefore,
the EPA was directed to set
priorities and establish a list
of sites to target. Sites on the
NPL (1,236) are thus a rela-
iii
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lively small subset of a larger
inventory of potential hazard-
ous waste sites, but they do
comprise the most complex
and environmentally compel-
ling cases. EPA has logged
more than 32,000 sites on its
National hazardous waste
inventory, and assesses each
site within one year of being
logged. In fact, over 90 per-
cent of the sites on the inven-
tory have been assessed. Of
the assessed sites, 55 percent
have been found to require no
further Federal action because
they did not pose significant
human health or environ-
mental risks. The remaining
sites are undergoing further
assessment to determine if
long-term Federal cleanup
activities are appropriate.
EPA IS MAKING
PROGRESS ON SITE
CLEANUP
The goal of the Superfund
program is to tackle immedi-
ate dangers first, and then
move through the progressive
steps necessary to eliminate
any long-term risks to public
health and the environment.
The Superfund responds
immediately to sites posing
imminent threats to human
health and the environment
at both NPL sites and sites
not on the NPL, The purpose
is to stabilize, prevent, or
temper the effects of a haz-
ardous release, or the threat
of one. These might include
tire fires or transportation
accidents involving the spill
of hazardous chemicals.
Because they reduce the
threat a site poses to human
health and the environment,
immediate cleanup actions
are an integral part of the
Superfund program.
Immediate response to immi-
nent threats is one of the
Superfund's most noted
achievements. Where immi-
nent threats to the public or
environment were evident,
EPA has completed or moni-
tored emergency actions that
attacked the most serious
threats to toxic exposure in
more than 1,800 cases.
The ultimate goal for a haz-
ardous waste site on the NPL
is a permanent solution to an
environmental problem that
presents a serious (but not an
imminent) threat to the public
or environment. This often
requires a long-term effort. In
the last four years, EPA has
aggressively accelerated its
efforts to perform these long-
term cleanups of NPL sites.
More cleanups were started
in 1987, when the Superfund
law was amended, than in
any previous year. And in
1989 more sites than ever
reached the construction
stage of the Superfund
cleanup process. Indeed
construction starts increased
by over 200 percent between
late 1986 and 1989! Of the
sites currently on the NPL,
more than 500 — nearly half
— have had construction
cleanup activity. In addition,
over 500 more sites are pres-
ently in the investigation
stage to determine the extent
of site contamination, and to
identify appropriate cleanup
remedies. Many other sites
with cleanup remedies se-
lected are poised for the start
of cleanup construction activ-
ity. Measuring success by
"progress through the
cleanup pipeline," EPA is
clearly gaining momentum.
EPA MAKES SURE
CLEANUP WORKS
EPA has gained; enough
experience in cleanup con-
struction to understand that
environmental protection
does not end when the rem-
edy is in place. Many com-
plex technologies — like
those designed to clean up
groundwater — must operate
for many years in order to
accomplish their objectives.
EPA's hazardous waste site
managers are committed to
proper operation and mainte-
nance of every remedy con-
structed. No matter who has
been delegated responsibility
for monitoring the cleanup
work, the EPA will assure
that the remedy is carefully
followed and that it continues
to do its job.
Likewise, EPA does not
abandon a site even after the
cleanup work is done. Every
IV
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five years the Agency reviews
each site where residues from
hazardous waste cleanup still
remain to ensure that public
and environmental health are
still being safeguarded. EPA
will correct any deficiencies
discovered and report to the
public annually on all five-
year reviews conducted that
year.
CITIZENS HELP SHAPE
DECISIONS
Superfund activities also
depend upon local citizen
participation. EPA's job is to
analyze the hazards and
deploy the experts, but the
Agency needs citizen input as
it makes choices for affected
communities.
Because the people in a
community with a Superfund
site will be those most di-
rectly affected by hazardous
waste problems and cleanup
processes, EPA encourages
citizens to get involved in
cleanup decisions. Public in-
volvement and comment does
influence EPA cleanup plans
by providing valuable infor-
mation about site conditions,
community concerns and
preferences.
This State volume and the
companion National Over-
view volume provide general
Superfund background
information and descriptions
of activities at each State NPL
site. These volumes are
intended to clearly describe
what the problems are, what
EPA and others participating
in site cleanups are doing,
and how we as a Nation can
move ahead in solving these
serious problems.
USING THE STATE AND
NATIONAL VOLUMES
IN TANDEM
To understand the big picture
on hazardous waste cleanup,
citizens need to hear about
both environmental progress
across the country and the
cleanup accomplishments
closer to home. The public
should understand the chal-
lenges involved in hazardous
waste cleanup and the deci-
sions we must make — as a
Nation — in finding the best
solutions.
The National Overview
volume — Superfund: Focus-
ing on the Nation at Large —
accompanies this State vol-
ume. The National Overview
contains important informa-
tion to help you understand
the magnitude and challenges
facing the Superfund pro-
gram as well as an overview
of the National cleanup effort.
The sections describe the
nature of the hazardous
waste problem nationwide,
threats and contaminants at
NPL sites and their potential
effects on human health and
the environment, the Super-
fund program's successes in
cleaning up the Nation's
serious hazardous waste sites,
and the vital roles of the
various participants in the
cleanup process.
This State volume compiles
site summary fact sheets on
each State site being cleaned
up under the Superfund
program. These sites repre-
sent the most serious hazard-
ous waste problems in the
Nation, and require the most
complicated and costly site
solutions yet encountered.
Each State book gives a
"snapshot" of the conditions
and cleanup progress that has
been made at each NPL site in
the State through the first half
of 1990. Conditions change as
our cleanup efforts continue,
so these site summaries will
be updated periodically to
include new information on
progress being made.
To help you understand the
cleanup accomplishments
made at these sites, this State
volume includes a description
of the process for site discov-
ery, threat evaluation and
long-term cleanup of Super-_
fund sites. This description
— How Does the Program
Work to Clean Up Sites? —
will serve as a good reference
point from which to review
the cleanup status at specific
sites. A glossary also is
included at the back of the
book that defines key terms
used in the site fact sheets as
they apply to hazardous
waste management.
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VI
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T" he diverse problems posed by the Nation's hazardous
" waste sites have provided EPA with the challenge to
establish a consistent approach for evaluating and
cleaning up the Nation's most serious sites. To do this, EPA
had to step beyond its traditional role as a regulatory agency
to develop processes and guidelines for each step in these
technically complex site cleanups. EPA has established proce-
dures to coordinate the efforts of its Washington, D.C. Head-
quarters program offices and its front-line staff in 10 Regional
Offices with the State governments, contractors, and private
parties who are participating in site cleanup. An important
part of the process is that any time during cleanup, work can
be led by EPA or the State or, under their monitoring, by
private parties who are potentially responsible for site con-
tamination.
The process for discovery of the site, evaluation of threat, and
long-term cleanup of Superfund sites is summarized in the
following pages. The phases of each of these steps are high-
lighted within the description. The flow diagram below pro-
vides a summary of this three step process.
STEP1
Discover site
and determine
whether an
emergency
exists *
STEP 2
Evaluate whether
a site is a serious
threat to public
health or
environment
STEP 3
Perform long-term
cleanup actions on
the most serious
hazardous waste
sites in the Nation
'Emergency actions are performed zvhenever needed in this three-step process
FIGURE 1
Although this State book provides a current "snapshot" of site progress made only by emer-
gency actions and long-term cleanup actions at Superfund sites, it is important to understand
the discovery and evaluation process that leads up to identifying and cleaning up these most
serious uncontrolled or abandoned hazardous waste sites in the Nation. This discovery and
evaluation process is the starting point for this summary description.
Vll
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r How does
abottt potential
sit *
" hazardous
"sites?
TWhal happens If ^:*! -
I there is »n~
* danger?
jr
rlfthere isn't an
i-imminettt
^how does EPA,
.^determine wltkt^il:
•*
deamip
"T*-* - " "
e taken?
Vv
STEP 1: SITE DISCOVERY AND EMERGENCY
EVALUATION
Site discovery occurs in a number of ways. Information
comes from concerned citizens — people may notice an odd
taste or foul odor in their drinking water, or see half-buried
leaking barrels; a hunter may come across a field where waste
was dumped illegally. Or there may be an explosion or fire
which alerts the State or local authorities to a problem. Rou-
tine investigations by State and local governments, and re-
quired reporting and inspection of facilities that generate,
treat, store, or dispose of hazardous waste also help keep EPA
informed about either actual or potential threats of hazardous
substance releases. All reported sites or spills are recorded in
the Superfund inventory (CERCLIS) for further investigation
to determine whether they will require cleanup.
As soon as a potential hazardous waste site is reported, EPA
determines whether there is an emergency requiring an imme-
diate cleanup action. If there is, they act as quickly as possible
to remove or stabilize the imminent threat. These short-term
emergency actions range from building a fence around the
contaminated area to keep people away or temporarily relo-
cating residents until the danger is addressed, to providing
bottled water to residents while their local drinking water
supply is being cleaned up, or physically removing wastes for
safe disposal.
However, emergency actions can happen at any time an imminent
threat or emergency warrants them — for example, if leaking
barrels are found when cleanup crews start digging in the
ground or if samples of contaminated soils or air show that
there may be a threat of fire or explosion, an immediate action
is taken.
STEP 2: SITE THREAT EVALUATION
Even after any imminent dangers are taken care of, in most
cases contamination may remain at the site. For example,
residents may have been supplied with bottled water to take
care of their immediate problem of contaminated well water.
But now if s time to figure out what is contaminating the
drinking water supply and the best way to clean it up. Or
viii
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EPA may determine that there is no imminent danger from a
site, so now any long-term threats need to be evaluated. In
either case, a more comprehensive investigation is needed to
determine if a site poses a serious but not imminent danger,
and requires a long-term cleanup action.
Once a site is discovered and any needed emergency actions
are taken, EPA or the State collects all available background
information not only from their own files, but also from local
records and U.S. Geological Survey maps. This information is
used to identify the site and to perform a preliminary assess-
ment of its potential hazards. This is a quick review of readily
available information to answer the questions:
• Are hazardous substances likely to be present?
• How are they contained?
• How might contaminants spread?
• How close is the nearest well, home, or natural resource
area like a wetland or animal sanctuary?
• What may be harmed — the land, water, air, people,
plants, or animals?
Some sites do not require further action because the prelimi-
nary assessment shows that they don't threaten public health .
or the environment. But even in these cases, the sites remain
listed in the Superfund inventory for record keeping purposes
and future reference. Currently, there are more than 32,000
sites maintained in this inventory.
Inspectors go to the site to collect additional information to
evaluate its hazard potential. During this site inspection, they
look for evidence of hazardous waste, such as leaking drums
and dead or discolored vegetation. They may take some
samples of soil, well water, river water, and air. Inspectors
analyze the ways hazardous materials could be polluting the
environment — such as runoff into nearby streams. They also
check to see if people (especially children) have access to the
site.
If the preliminary"
assessment s&ows
trhat a seiiotis threat
utay exist what's
next step?
Information collected during the site inspection is used to
identify the sites posing the most serious threats to human
health and the environment. This way EPA can meet the
How does
of the
IX
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requirement that Congress gave them to use Superfund mo-
nies only on the worst hazardous waste sites in the Nation.
To identify the most serious sites, EPA developed the Hazard
Ranking System (HRS). The HRS is the scoring system EPA
uses to assess the relative threat from a release or a potential
release of hazardous substances from a site to surrounding
groundwater, surface water, air, and soil. A site score is based
on the likelihood a hazardous substance will be released from
the site, the toxicity and amount of hazardous substances at
the site, and the people and sensitive environments potentially
affected by contamination at the site.
Only sites with high enough health and environmental risk
scores are proposed to be added to EPA's National Priorities
List (NPL). That's why there are 1,236 sites are on the NPL,
but there are more than 32,000 sites in the Superfund inven-
tory. Only NPL sites can have a long-term cleanup paid for
from the national hazardous waste trust fund — the Super-
fund. But the Superfund can and does pay for emergency
actions performed at any site, whether or not it's on the NPL.
Mow do people laid- " j The public can find out whether a site that concerns them is
,7,^; ' on the NPL by calling their Regional EPA office jat the number
*^ " 5 listed in this book. -
t
g*"
ia$S*fs^s V:
|national priority foj£ tV 1 The proposed NPL identifies sites that have been evaluated
f.cleanup using :v}%c ^ through the scoring process as the most serious problems
!" StXperftmd money? - ^|^i among uncontrolled or abandoned hazardous waste sites in
' ...^.s.^vi the U.S. In addition, a site will be added to the NPL if the
Agency for Toxic Substances and Disease Registry issues a
health advisory recommending that people be moved away
from the site. Updated at least once a year, it's only after
public comments are considered that these proposed worst
sites are officially added to the NPL.
Listing on the NPL does not set the order in which sites will be
cleaned up. The order is influenced by the relative priority of
the site's health and environmental threats compared to other
sites, and such factors as State priorities, engineering capabili-
ties, and available technologies. Many States also have their
own list of sites that require cleanup; these often contain sites
not on the NPL that are scheduled to be cleaned up with State
money. And it should be said again that any emergency action
needed at a site can be performed by the Superfund whether
or not a site is on the NPL.
It-
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STEP 3: LONG-TERM CLEANUP ACTIONS
The ultimate goal for a hazardous waste site on the NPL is a
permanent, long-term cleanup. Since every site presents a
unique set of challenges, there is no single all-purpose solu-
tion. So a five-phase "remedial response" process is used to
develop consistent and workable solutions to hazardous waste
problems across the Nation:
1. Investigate in detail the extent of the site contamination:
remedial investigation,
2. Study the range of possible cleanup remedies: feasibility
study,
3. Decide which remedy to use: Record of Decision or ROD,
4. Plan the remedy: remedial design, and
5. Carry out the remedy: remedial action.
This remedial response process is a long-term effort to provide
a permanent solution to an environmental problem that
presents a serious, but not an imminent threat to the public or
environment.
The first two phases of a long-term cleanup are a combined
remedial investigation and feasibility study (RI/FS) that
determine the nature and extent of contamination at the site,
and identify and evaluate cleanup alternatives. These studies
may be conducted by EPA or the State or, under their monitor-
ing, by private parties.
Like the initial site inspection described earlier, a remedial
investigation involves an examination of site data in order to
better define the problem. But the remedial investigation is
much more detailed and comprehensive than the initial site
inspection.
A remedial investigation can best be described as a carefully
designed field study. It includes extensive sampling and
laboratory analyses to generate more precise data on the types
and quantities of wastes present at the site, the type of soil and
water drainage patterns, and specific human health and
environmental risks. The result is information that allows
EPA to select the cleanup strategy that is best suited to a
particular site or to determine that no cleanup is needed.
a site is,
fff ., .. ft
to 4he NPL, what a*e
steps to eleamro?
f : ;;
tf-w.
XI
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Placing a site on the NPL does not necessarily mean that
cleanup is needed. It is possible for a site to receive an HRS
score high enough to be added to the NPL, but not ultimately
require cleanup actions. Keep in mind that the purpose of the
scoring process is to provide a preliminary and conservative
assessment of potential risk. During subsequent site investiga-
tions, the EPA may find either that there is no real threat or
that the site does not pose significant human health or envi-
ronmental risks.
? How are cleanup
alternatives
(identified and
f evaluated?
EPA or the State or, under their monitoring, private parties
identify and analyze specific site cleanup needs based on the
extensive information collected during the remedial investiga-
tion. This analysis of cleanup alternatives is called a feasibility
study.
Since cleanup actions must be tailored exactly to the needs of
each individual site, more than one possible cleanup alterna-
tive is always considered. After making sure that all potential
cleanup remedies fully protect human health and the environ-
ment and comply with Federal and State laws, the advantages
and disadvantages of each cleanup alternative are carefully
compared. These comparisons are made to determine their
effectiveness in the short- and long-term, their .use of perma-
nent treatment solutions, and their technical feasibility and
cost.
To the maximum extent practicable, the remedy must be a
permanent solution and use treatment technologies to destroy
principal site contaminants. But remedies such as containing
the waste on site or removing the source of the problem (like
leaking barrels) are often considered effective. Often special
pilot studies are conducted to determine the effectiveness and
feasibility of using a particular technology to clean up a site.
Therefore, the combined remedial investigation and feasibility
study can take between 10 and 30 months to complete, de-
pending on the size and complexity of the problem.
* Does the public KayeC, ^ Yes. The Superfund law requires that the public be given the
* a say m the final :
1 cleanup decision* -
opportunity to comment on the proposed cleanup plan. Their
concerns are carefully considered before a final decision is
made.
\
Xll
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The results of the remedial investigation and feasibility study,
which also point out the recommended cleanup choice, are
published in a report for public review and comment. EPA or
the State encourages the public to review the information and
take an active role in the final cleanup decision. Fact sheets
and announcements in local papers let the community know
where they can get copies of the study and other reference
documents concerning the site.
The public has a minimum of 30 days to comment on the
proposed cleanup plan after it is published. These comments
can either be written or given verbally at public meetings that
EPA or the State are required to hold. Neither EPA nor the
State can select the final cleanup remedy without evaluating
and providing written answers to specific community com-
ments and concerns. This "responsiveness summary" is part
of EPA's write-up of the final remedy decision, called the
Record of Decision or ROD.
The ROD is a public document that explains the cleanup
remedy chosen and the reason it was selected. Since sites
frequently are large and must be cleaned up in stages, a ROD
may be necessary for each contaminated resource or area of
the site. This may be necessary when contaminants have
spread into the soil, water and air, and affect such sensitive
areas as wetlands, or when the site is large and cleaned up in
stages. This often means that a number of remedies using
different cleanup technologies are needed to clean up a single
site.
Yes. Before a specific cleanup action is carried out, it must be
designed in detail to meet specific site needs. This stage of the
cleanup is called the remedial design. The design phase
provides the details on how the selected remedy will be
engineered and constructed.
Projects to clean up a hazardous waste site may appear to be
like any other major construction project but, in fact, the likely
presence of combinations of dangerous chemicals demands
special construction planning and procedures. Therefore, the
design of the remedy can take anywhere from 6 months to 2
years to complete. This blueprint for site cleanup includes not
only the details on every aspect of the construction work, but a
description of the types of hazardous wastes expected at the
-" «, \,
If eveiy cleanup
action needs, to foe -'--
tailored tent site, does
the design of the
remedy steed to fee
tailored toot
Xlll
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SUPERFUND
xft
site, special plans for environmental protection, worker safety,
regulatory compliance, and equipment decontamination.
Once tiie desigpifs
complete, how
does it take to
actually clean up
I site and tiow much
* does it cost?
The time and cost for performing the site cleanup — called the
remedial action — are as varied as the remedies themselves.
In a few cases, the only action needed may be to remove
drums of hazardous waste and decontaminate them — an
action that takes limited time and money. In most cases,
however, a remedial action may involve different and expen-,
sive measures that can take a long time.
For example, cleaning polluted ground water or dredging , • ••
contaminated river bottoms can take several years of complex
engineering work before contamination is reduced to safe
levels. Sometimes the selected cleanup remedy described in
the ROD may need to be modified because of new contami- ,,
nant information discovered or difficulties that were faced .
during the early cleanup activities. Taking into account these
differences, a remedial cleanup action takes an average of 18
months to complete and costs an average of $26 million per
site.
jv ""w 5V
I Once the cleanup
- action is compile/ is
* the site automatically*
t "deleted" &om ttie J
? NPL? \ s ^
*•*.*} ' *
No. The deletion of a site from the NPL is anything but auto-
matic. For example, cleanup of contaminated grotindwater
may take up to 20 years or longer. Also, in some cases the
long-term monitoring of the remedy is required to ensure that
it is effective. After construction of certain remedies, opera-
tion and maintenance (e.g., maintenance of ground cover,
groundwater monitoring, etc.) or continued pumping and
treating of groundwater, may be required to ensure that the
remedy continues to prevent future health hazards or environ-
mental damage, and ultimately meets the cleanup goals
specified in the ROD. Sites in this final monitoring or opera-
tional stage of the cleanup process are designated as "con-
struction completed".
If s not until a site cleanup meets all the goals and monitoring
requirements of the selected remedy that EPA can officially
propose the site for "deletion" from the NPL. And it's not
until public comments are taken into consideration that a site
can actually be deleted from the NPL. Deletions that have
occurred are included in the "Construction Complete" cate-
gory in the progress report found later in this book.;
xiv
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Yes. Based on the belief that "the polluters should pay/' after a
site is placed on the NPL, the EPA makes a thorough effort to
identify and find those responsible for causing contamination
problems at a site. Although EPA is willing to negotiate with
these private parties and encourages voluntary cleanup, it has
the authority under the Superfund law to legally force those
potentially responsible for site hazards to take specific cleanup
actions. All work performed by these parties is closely guided
and monitored by EPA, and must meet the same standards
required for actions financed through the Superfund.
Because these enforcement actions can be lengthy, EPA may
decide to use Superfund monies to make sure a site is cleaned
up without unnecessary delay. For example, if a site presents
an imminent threat to public health and the environment, or if
conditions at a site may worsen, it could be necessary to start
the cleanup right away. Those responsible for causing site
contamination are liable under the law for repaying the money
EPA spends in cleaning up the site.
Whenever possible, EPA and the Department of Justice use
their legal enforcement authorities to require responsible
parties to pay for site cleanups, thereby preserving the Super-
fund for emergency actions and sites where no responsible
parties can be identified.
Cm EPA make patties
for the
XV
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TAX
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The Site Fact Sheets
presented in this book
,, are comprehensive
summaries that cover a broad
range of information. The
fact sheets describe hazard-
ous waste sites on the Na-
tional Priorities List (NPL)
and their locations, as well as
the conditions leading to their
listing ("Site Description").
They list the types of con-
taminants that have been dis-
covered and related threats to
public and ecological health
("Threats and Contami-
nants"). "Cleanup Ap-
proach" presents an overview
of the cleanup activities
completed, underway, or
planned. The fact sheets
conclude with a brief synop-
sis of how much progress has
been made on protecting
public health and the envi-
ronment. The summaries also
pinpoint other actions, such
as legal efforts to involve pol-
luters responsible for site
contamination and commu-
nity concerns.
The following two pages
show a generic fact sheet and
briefly describes the informa-
tion under each section. The
square "icons" or symbols ac-
companying the text allow
the reader to see at a glance
which environmental re-
sources are affected and the
status of cleanup activities.
Icons in the Threats
and Contaminants
Section
Contaminated
Groundwater re-
sources in the vicinity
or underlying the site.
(Groundwater is often used
as a drinking water source.)
Contaminated Sur-
face Water and
Sediments on or near
the site. (These include lakes,
ponds, streams, and rivers.)
Contaminated Air in
the vicinity of the
site. (Pollution is
usually periodic and involves
contaminated dust particles
or hazardous gas emissions.)
Contaminated Soil
and Sludges on or
near the site.
Threatened or
contaminated Envi-
ronmentally Sensi-
tive Areas in the vicinity of
the site. (Examples include
wetlands and coastal areas,
critical habitats.)
Icons in the Response
Action Status Section
Actions
have been taken or
are underway to
eliminate immediate threats
Site Studies at the
site are planned or
underway.
Remedy Selected
indicates that site
investigations have
been concluded
and EPA has se-
lected a final cleanup remedy
for the site or part of the site.
Remedy Design
means that engi-
neers are prepar-
ing 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 — are currently
underway.
Cleanup Complete
shows that all
cleanup goals have
been achieved for
the contaminated site or part
of the site.
xvii
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Site Responsibility
Identifies the Federal, State,
and/or potentially responsible
parties that are taking
responsibility for cleanup
actions at the site.
EPA REGION
CONGRESSIONAL DIST
, County Name
SITE NAME
STATE
EPA ID# ABCOOOOOOOO
NPL Listing
History
Dates when the site
was Proposed,
made Final, and
Deleted from the
NPL
Threats and Contaminants
Cleanup Approach
Response Action Status
Environmental Progress
A summary of the actions to reduce the threats to nearby residents and
the surrounding environment; progress towards cleaning up the site
and goals of the cleanup plan are given here.
xviii
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WHAT THE FACT SHEETS CONTAIN
Site Description
This section describes the location and history of the site. It includes
descriptions of the most recent activities and past actions at the site that have
contributed to the contamination. Population estimates, land usages, and nearby
resources give readers background on the local setting surrounding the site.
Throughout the site description and other sections of the site summary, technical
or unfamiliar terms that are italicized are presented in the glossary at the end of
the book. Please refer to the glossary for more detailed explanation or definition
of the terms.
Threats and Contaminants
The major chemical categories of site contamination are noted as well as
which environmental res9urces 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
environments arising from the site contamination are also described. Specific
contaminants and contaminant groupings are italicized and explained in more
detail in the glossary. ,
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 are often 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 description.
Site Facts
Additional informa^n on activities and events at the site are included in this
section. Often details on legal or administrative actions taken by EPA to achieve
site cleanup or other facts pertaining to community involvement with the site
cleanup process are reported here.
XIX
-------
The fact sheets are arranged
in alphabetical order by site
name. Because site cleanup is
a dynamic and gradual
process, all site information is
accurate as of the date shown
on the bottom of each page.
Progress is always being
made at NPL sites, and EPA
will periodically update the
Site Fact Sheets to reflect
recent actions and publish
updated State volumes.
HOW CAN YOU USE
THIS STATE BOOK?
You can use this book to keep
informed about the sites that
concern you, particularly
ones close to home. EPA is
committed to involving the
public in the decisionmaking
process associated with
hazardous waste cleanup.
The Agency solicits input
from area residents in com-
munities affected by Super-
fund 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 differ-
ent 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
EPA intends to clean up the
site. You must understand
the cleanup alternatives being
proposed for site cleanup and
how residents may be af-
fected by each one. You also
need to have some idea of
how your community intends
to use the site in the future
and to know what the com-
munity can realistically
expect once the cleanup is
complete.
EPA wants to develop
cleanup methods that meet
community needs, but the
Agency can only 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 in-
volved, and assure that
hazardous waste cleanup at
"your" site considers your
community's concerns.
xx
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NPL Sites i
State of Colora
Colorado lies in the west central United-States and is bordered by Wyoming to the
north. New Mexico and Oklahoma to the south, Nebraska and Kansas to the east, and
Utah to the west. The State covers 104,091 square miles consisting of high plain's in
the east, a hilly to mountainous plateau in the central section, and the Rocky Mountains
with high ranges, broad valleys, and deep canyons in the west. Colorado experienced a
14.2 percent increase in population through the 1980s and currently has approximately
3,301,000 residents, ranking 26th in U.S. populations. Principal state industries include
government, tourism, agriculture, and aerospace. Colorado manufacturing produces
electronics equipment, foods, and machinery.
How Many Colorado Sites
Are on the NPL?
Proposed Sites.
Final Sites
Deleted Sites
1
15
_Q
16
Where Are the NPL Sites Located?
Cong. District 01 2 sites
Cong. District 02, 03, 04 4 sites
Cong. District 05, 06 1 site
15--
How are Sites Contaminated and What are the Principal* Chemicals ?
Groundwater: Volatile organic
compounds (VOCs), heavy
metals (inorganics), and radiation.
Soil: Heavy metals (inorganics),
creosotes {organics}, pesticides,
and radiation.
Surface Water and Sediments:
Heavy metals (inorganics),
creosotes (organics), volatile
organic compounds (VOCs),
pesticides, and radiation.
Air: Radiation.
GW Soil SW Sed
Contamination Area
Air
* Appear at 20% or more sites
State Overview
continued
-------
Where are the Sites in the Superfund Cleanup Process*?
Construction
Complete
Initial actions have been taken at 13 sites as interim cleanup measures.
Who Do I Call with Questions?
The following pages describe each NPL site in Colorado, providing specific information
on threats and contaminants, cleanup activities, and environmental progress. Should
you have questions, please call one of the offices listed below:
Colorado Superfund Office
EPA Region VIII Superfund Office
EPA Region VIII Superfund Community Relations
EPA Headquarters Public Information Center
EPA Superfund Hotline
(303) 331-4830
(303)293-1720
(303)294-1144
(202) 475-7751
(800) 424-9346
'Cleanup status reflects phase of site activities rather than administrative accomplishments.
State Overview
XXII
-------
The NPL Progress Report
The following Progress Report lists the State sites currently on or deleted from the NPL,
and briefly summarizes the status of activities for each site at the time this report was
prepared. The steps in the Superfund cleanup process are arrayed across the top of the
chart, and each site's progress through these steps is represented by an arrow (»>-) which
indicates the current stage of cleanup at the site.
Large and complex sites are often organized into several cleanup stages. For example,
separate cleanup efforts may be required to address the source of the contamination,
hazardous substances in the groundwater, and surface water pollution, or to clean up
different areas of a large site. In such cases, the chart portrays cleanup progress at the
site's most advanced stage, reflecting the status of site activities rather than administrative
accomplishments.
«K An arrow in the "Initial Response" category indicates that an emergency cleanup or
initial action has been completed or is currently underway. Emergency or initial actions
are taken as an interim measure to provide immediete relief from exposure to
hazardous site conditions or to stabilize a site to prevent further contamination.
•»- An arrow in the "Site Studies" category indicates that an investigation to determine the
nature and extent of the contamination at the site is currently ongoing or planned to
begin in 1991.
•*- An arrow in the "Remedy Selection" category means that the EPA has selected the
final cleanup strategy for the site. At the few sites where the EPA has determined that
initial response actions have eliminated site contamination, or that any remaining
contamination will be naturally dispersed without further cleanup activities, a "No
Action" remedy is selected. In these cases, the arrows in the Progress Report are
discontinued at the "Remedy Selection" step and resume in the final "Construction
Complete "-category.
•*- An arrow at the "Remedial Design" stage indicates that engineers are currently
designing the technical specifications for the selected cleanup remedies and
technologies.
•fr- An arrow marking the "Cleanup Ongoing" category means that final cleanup actions
have been started at the site and are currently underway.
*- A arrow in the "Construction Complete" category is used on/y when all phases of the
site cleanup plan have been performed and the EPA has determined that no additional
construction actions are required at the site. Some sites in this category may currently
be undergoing long-term pumping and treating of groundwater, operation and
maintenance or monitoring to ensure that the completed cleanup actions continue to
protect human health and the environment.
The sites are listed in alphabetical order. Further information on the activities and progress
at each site is given in the site "Fact Sheets" published in this volume.
xxm
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Jfroj
Page
1
3
5
7
10
12
15
17
19
22
24
26
30
32
34
36
gress Toward, uieanup a
Site Name
AIR FORCE PLANT PJKS PROJECTS
BRODERICK WOOD PRODUCTS
CALIFORNIA GULCH
CENTRAL CITY-CLEAR CREEK
CHEMICAL SALES COMPANY
DENVER RADIUM SITE
EAGLE MINE
LINCOLN PARK
LOWRY LANDFILL
MARSHALL LANDFILL
ROCKY FLATS PLANT (USDOE)
ROCKY MOUNTAIN ARSENAL
SAND CREEK INDUSTRIAL
SMUGGLER MOUNTAIN
URAVAN URANIUM PROJECT
WOODBURY CHEMICAL COMPANY
t JNJFJL, dices
County
JEFFERSON
ADAMS
LAKE
CLEAR CREEK
DENVER
ADAMS
EAGLE
FREMONT
ARAPAHOE
BOULDER
JEFFERSON
ADAMS
ADAMS
PITKIN
MONTROSE
ADAMS
in in
NPL
Final
Final
Final
Final
Prop.
Final
Final
Final
Final
Final
Final
Final
Final
Final
Final
Final
e oiate 01 v;oioraao
Initial She Remedy Remedy Cleanup Construction
Date Response Studies Selected Design Ongoing Complete
11/21/89 •*- *-
09/21/84 •*- *" •*" "*•
09/08/83 *-***•*-•*•
09/08/83 *•*-*•*-*-
06/24/88 •*- •*•
09/08/83 •*- •*• •*- *• *•
06/10/86 *• "^ ^ "^ •*•
09/21/84 *" "*• "^ "^
09/21/84 "^ *"
09/08/83 •*" "^ "*" •>• "*"
10/04/89 "*- •*" "*" •*•
07/01/87 *- •*• "^ ^ "^
09/08/83 ^- ^ •*" •*•
06/01/86 "^ "^ •*• •*•
06/10/86 ^ "^ "*• •*"
09/08/83 •*" ^ ^ ^
XXIV
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-------
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AIR FORCE
PROJECTS
COLORADO
EPA IDS CO7570090038
PLHNl
REGION 8
CONGRESSIONAL DIST. 06
Jefferson County
Waterton
Site Description
The 464-acre Air Force Plant PJKS Projects site is surrounded by about 4,700 acres of
land owned by Martin Marietta. Since 1957, waste generation at the facility has
primarily consisted 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. A total
of 18 contamination plumes were found in two groundwater zones. Some of these
plumes are moving off Air Force property and onto the adjacent Martin Marietta
property. A total of 19 potential or known surface contamination sources were also
identified. The facility is located in a rural area with farming and ranching facilities.
Located nearby is a major recreational area used by local residents and visitors.
site Responsibility: This sjte js being addressed through
Federal, State, and potentially
responsible parties' actions.
NPL LISTING HISTORY
Proposed Date: 07/14/89
Final Date: 11/21/89
Threats and Contaminants
Monitoring wells have detected TCE and freon contamination in the
groundwater. Discovery of thorium and gross alpha, beta, and gamma
radiation led the Air Force to some low-level drummed wastes in a landfill.
Brush Creek, located on the site, also contains TCE. People who touch or
accidentally ingest contaminated surface water, groundwater, or soil may
suffer adverse health effects.
March 1990
NPL HAZARDOUS WASTE SITES
1
continued
-------
AIR FORCE PLANT PJKS PROJECTS
Cleanup Approach
This site is being addressed in a single long-term remedial phase focusing on cleanup
of the entire site. |
Response Action Status
Immediate Action: Air Force monitoring revealed thorium and gross
alpha, beta, and gamma radiation. This contamination was traced to a
, . small quantity of low-level radioactive alloy buried in drums in 1971. The
Air Force located the magnesium-thorium alloy and removed the drums safely off site in
1986 to a regulated disposal facility. 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 at
the site that was reviewed by the EPA and the State. Further ; '
, ^ investigations are needed to determine contamination in deeper ; .
groundwater zones. The Air Force is preparing plans to conduct further investigations
at certain contamination sources and the deeper groundwater zones. Cleanup ;_
strategies for some surface sources and groundwater contamination are also being
developed. .
Site Facts: The Air Force Plant PJKS Projects site is participating in the Installation
Restoration Program (IRP), a federally funded Department of Defense (DOD) effort to
identify, investigate, and control hazardous waste at military installations.
The removal of contaminated drums has greatly reduced the potential for exposure to
hazardous materials at the Air Force Plant PJKS Projects site while further ;
investigations and cleanup activities are taking place.
A
-------
BRODERICK WOO
PRODUCTS
COLORADO
EPA ID# COD000110254
REGION 8
CONGRESSIONAL DIST. 02
Adams County
Denver
Site Description
The 64-acre Broderick Wood Products site is a former wood treatment plant with three
main activities having contributed to contamination: wood treatment operations
between 1947 and 1981; railroad shops on site before 1947; and smelting operations
on adjacent property. 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 northwest corner. These are called
the "main" and "secondary" impoundments, and are the main sources of
contamination totaling 4,000 cubic yards on the site. The main impoundment contains
a surface layer of oil and grease, a water layer, and a sludge layer. The secondary
impoundment holds mainly sludge. No industrial activities currently take place on the
site, but contaminated buildings, equipment, and wastewater ponds still exist. None of
the four former ponds appear to have received plant wastewater, although a number of
waste pits have been discovered. The main access road to the site is barricaded, the
treatment building is fenced, the ponds have a snow fence around them, and the site is
posted. A water supply well on the site was abandoned in the early 1970s, but several
homes north of the site continue to use well water for domestic supply".'' Fisher Ditch
distributes water to irrigation ditches that flow to Copeland Lake, 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 lies
1/2 mile to the north; as well as, a sanitary landfill and areas where sand and gravel
mining have occurred.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties'actions.
Threats and Contaminants
IMPL LISTING HISTORY
Proposed Date: 09/08/83
Final Date: 09/21/84
Groundwater, surface water, and soil are contaminated with various
polycyclic aromatic hydrocarbons (PAHs), PCP, and volatile organic
compounds (VOCs). In addition, soil and surface water are contaminated
with various heavy metals. People may incur health risks by touching or
accidentally ingesting contaminated groundwater, surface water, or soil.
March 1990
NPL HAZARDOUS WASTE SITES
3
continued
-------
BRODERICK WOOD PRODUCTS
Cleanup Approach
This site is being addressed in two long-term remedial phases focusing on cleanup of
the surface impoundments and soil and groundwater cleanup. ;
Response Action Status
Surface Impoundments: The EPA selected a remedy for the cleanup of
surface impoundments in 1988 featuring: (1) bringing a mobile incinerator
onto the site; {2} excavating and incinerating the sludge and oil in the two
impoundments; (3) disposing of the remaining ash off site; (4) treating contaminated
impoundment wastewater with activated carbon; (5) filtering the water in the plant
basement to remove asbestos fibers; (6) letting cleaned waters evaporate or using
them as incinerator quench water;'(7) excavating visibly contaminated soil beneath the
impoundments and burning small volumes on site (if volumes are large, storing on site
for further study); and (8) monitoring groundwater. In addition, workers will construct a
security fence around the site and install warning signs. The parties potentially
responsible for site contamination installed the security fence in 1989. The EPA
completed the engineering design for the remedy in 1989. Cleanup actions are
currently under way at the site and scheduled for completion in 1990. i
Soils and Groundwater: In 1989, the potentially responsible parties
began an investigation, under EPA monitoring, that will further explore the
. ,„ nature and extent of soil and groundwater pollution at and around the
property and will recommend the best strategies for final cleanup. The study is
scheduled for completion in 1990.
Site Facts: The EPA negotiated with Broderick Investment Company for studies to be
conducted at the site and signed a partial Consent Decree in 1986 requiring the
company to conduct a site investigation.
Environ niental Progress
The installation of a security fence and the ongoing cleanup of the surface , <
impoundments at the Broderick Wood Products site have greatly reduced the potential
for exposure to hazardous materials while further investigations into the remaining
contamination areas and cleanup activities are taking place.
-------
CALIFORNIA
COLORADO
EPAID# COD980717938
REGION 8
CONGRESSIONAL DIST. 05
Lake County
100 miles west of Denver
Site Description
The 130-year-old California Gulch site is a mining area that covers 11 1/2 square miles
of a watershed area that drains along California Gulch to the Arkansas River. Starting in
1859, the area has been mined extensively for gold, lead, silver, copper, zinc, and
manganese. California Gulch contains numerous abandoned mines and wastes from
mining, milling, and smelting. 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 mines in its 4-mile underground course and discharges a total of 210 tons
of various heavy metals each year into California Gulch. Although the tunnel mainly
contaminates surface water/heavy metals have also moved through surface water to
pollute groundwater and sediments. California Gulch also collects runoff from several
other gulches that drain other mine tailings piles and pond wastes. Some of this 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 supply, and fisheries.
Approximately 6,000 people live in nearby Leadville and Lake County.
Site Responsibility:
This site is being addressed through
Federa.l 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 cadmium, copper, lead, and zinc. The water in
several shallow groundwater wells in California Gulch and in some private
wells have also been shown to exceed EPA drinking water standards for
cadmium and zinc. Arsenic, cadmium, and lead exist 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 plant tissues in some cases contained levels of metals
toxic to livestock and wildlife. Water in the main stem of California Gulch
is unsafe for drinking.
March 1990
NPL HAZARDOUS WASTE SITES
5
continued
-------
CALIFORNIA GULCH
Cleanup Approach
This site is being addressed in three stages: an immediate action and two long-term
remedial phases focusing on cleanup of the Yak Tunnel and cleanup of groundwater
and surface water.
Response Action Status
Immediate Action: In 1986, EPA emergency workers extended public.
water supply system lines to residences using private wells.
Yak Tunnel: In 1988, the EPA selected a remedy to minimize the flow of
acid water from the Yak Tunnel and to prevent the uncontrolled release of
tunnel drainage to the environment. It features: (1) building a surge pond
to capture tunnel drainage and dissipate the effect of surges from the
tunnel on the Gulch and River; (2) installing a permanent system to treat the tunnel
water before discharging it; (3) installing plugs at three places in the tunnel to stop the
uncontrolled discharge of mine drainage; (4) sealing shafts, drill holes, and fractured
rock and diverting surface water to reduce the amount of water entering the tunnel; (5)
establishing a surface and groundwater monitoring system; and (6) installing a;pumping
or drainage system to control water levels. Under EPA monitoring, 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 are currently sealing approaches.and designing the tunnel plugs and the
permanent treatment plant. Cleanup activities for these aspects are scheduled to begin
in 1990.
Groundwater and Surface Water: The EPA began an investigation of
mine wastes at the site in 1987. The investigations are exploring the
, w nature and extent of the water pollution caused by mine tailings piles and
ponds, smelter slags, and mine waste dumps. Site investigations are scheduled to end
in 1992.
Environmental Progress
Extending the public water supply has provided safe drinking water for affected area
residents. Ongoing work to control surface runoff and to prevent further contamination
from the California Gulch site continues to provide environmental protection while
permanent treatments are sought for contaminated surface and groundwater.;
-------
CENTRAL
CREEK
COLORADO
EPAID# COD980717557
REGIONS
CONGRESSIONAL DIST. 02
Clear Creek and Gilpto County
20 miles west of Denver
Aliases:
Argo Tunnel
Central City Mining District
Gregory Incline
Newhouse Tunnel
Big Five Tunnel ,
National Tunnel
Site Description
The Central City/Clear Creek site covers over 50 river miles, in north central Colorado
near Central City and Idaho Springs. The site encompasses the Clear Creek drainage
basin, which has been affected by a number of inactive gold mines, including five major
areas that the EPA has identified: Argo Tunnel (on Clear Creek); Big Five Tunnel (on - '••
Clear Creek); National Tunnel (on North Clear Creek); Gregory Incline (on North Clear
Creek); and Quartz Hill Tunnel (on North Clear Creek). The Clear Creek/Central City
Mining District contains numerous .abandoned mine tailings and waste rock piles,
mining tunnels, and open shafts. The 4-mile Argo Tunnel, completed in 1904, drains
water from numerous inactive mines. The acidic water that drains from these mines
contains various dissolved heavy metals and flows from the tunnels into the creek and.
other tributaries feeding into Clear Creek. During storms and annual snowmelts, water
erodes the tailings piles, picks up contaminants from the piles, and flows into the
creeks. Clear Creek is an important source of water to local industry, agriculture, and to
people in the area who use it for drinking water and recreation. In 1980, a sudden
discharge or blow-out from the Argo Tunnel moved large amounts of contaminants into
Clear Creek, affecting users of the water farther downstream and contaminating
drinking water supplies. Approximately 2,441 people live in Gilpin County, and 7,308
people live in Clear Creek County. The population of this area increases slightly during
the warmer months due to tourism. Aquatic Ijfe in Clear Creek is sparse for many .miles
both above and below the Argo Tunnel. % .:
Site Responsibility:
This site is being addressed through
Federal and State actions.
NPL LISTING HISTORY
Proposed Date: 07/23/82
Final Date: 09/08/83
Threats and Contaminants
Soils, including tailings and waste rock from the tunnels, contains heavy
metals such as arsenic, cadmium, chromium, copper, and sulphur.
Groundwater and surface waters contain heavy metals. People can
become exposed to site-related contaminants by drinking contaminated
water from private wells in the shallow and deep aquifers or drinking
March 1990
NPL HAZARDOUS WASTE SITES
7
continued
-------
CENTRAL CITY-CLEAR CREEK
contaminated tap water from the Black Hawk municipal water supply
system during periods when the city supplements its surface water
supply from wells containing contaminated groundwater. Children may be
at risk from coming into direct contact with contaminated soil while
playing on the tailings piles-or on contaminated areas.
Cleanup Approach
The site is being addressed in four stages: immediate actions and three long-term
remedial phases directed at cleanup of the mine discharge treatment of surface water,
remediation of the tailings and waste rock and a Basin-wide study. :
Response Action Status
Immediate Actions: In 1987, the EPA constructed a new retaining wall
to support the waste rock and tailings known as the Gregory Tailings. The
—««».*«. EPA decreased the slope of the waste pile and replaced the retaining wall
to prevent it from collapsing into North Clear Creek. The EPA surveyed local
households to determine whether residents were using water from wells drilled into
the shallow aquifer. Of the few such wells being used, only one showed significant
levels of contamination from cadmium. The EPA arranged to provide the home with
clean water from the Idaho Springs municipal water supply and provided the residents
with bottled water as an interim measure. The EPA connected four other residences to
the city water supply; these wells were at risk from future contamination, because they
drew water from the same aquifer. The EPA conducted a second survey in 1989, but
no new problem wells were identified.
Mine Discharge Treatment of Surface Water Contaminants: The EPA
plans to construct a wetland as a passive treatment system to tresat mine
tunnel discharge before it reaches surface waters. This is the preferred
alternative and is contingent upon results of pilot studies. The EPA has
already constructed a pilot-treatment system to determine the ability of a passive
treatment to meet water quality standards upstream from the site. If water quality
concentrations cannot be achieved by passive treatment, a combination system of
passive and active treatment systems using chemical or electrochemical precipitation
will be constructed to treat mine tunnel discharge. These systems will be designed to
reduce the mobility, toxicity, or volume of dissolved and suspended metals in the mine
drainage, decrease the acidity of the mine drainage, and meet the levels of water
quality for waters upstream of the site. The EPA is currently carrying out the pilot
program and expects to complete the design for addressing contamination of the site
by early 1992. \
continued
-------
CENTRAL CITY-CLEAR CREEK
Tailings/Waste Rock Remediation: The selected remedy includes
stabilizing the slope at the Big Five Tunnel tailings and waste rock piles.
This will consist of. regrading portions of the piles to a stable configuration
and placing large boulders at the base to minimize erosion. The current Gabion wall at
the Gregory Incline will be maintained until monitoring indicates that more work is
needed to address the problem or until the tailings are removed for reprocessing. At
that time, a permanent solution will be carried out. Drainage control at all five tailings
and waste rock piles will consist of installing diversion ditches on the upslope sides of
the piles. The EPA will coordinate with the State and local officials to evaluate the use
of institutional measures to control any threats that future development on the tailings
and waste rock piles would pose.to people and the environment.
Argo Tunnel Discharge Control and Basin-Wide Study: In 1988, the
EPA conducted a study to evaluate ways to control further blow-outs from
occurring at the Argo Tunnel and for reducing or stopping water from
entering the tunnel. The State's study, funded by the EPA through a Cooperative
Agreement, was completed in the spring of 1990. A decision will be made on the Argo
Tunnel when the State study of the entire drainage basin is reviewed.
Site Facts: In 1989, the EPA entered into an Interagency Agreement with the U. S.
Bureau of Reclamation to proceed with the cleanup action.
Environmental Progress
The construction of a new retaining wall to support the waste rock and tailings has
prevented the waste pile from causing the further spread of contamination across the
ground at the Central City site. The EPA provided affected residents with bottled water
prior to hooking them up to the municipal water supply and later connected four other
residences to the city water supply. Remedies have been selected for the.stabilization
of the slope at the Big Five Tunnel tailings and waste rock piles. Also, studies on how
to control blow-outs from occurring and to reduce or stop water from entering the
tunnel are currently being conducted that will prevent future contamination events at
the site.
-------
CHEMICAL
COMPANY
COLORADO
EPAID* COD007431620
REGIONS
CONGRESSIONAL DIST. 01
Denver County
2 miles northwest of Stapleton
International Airport
Alias:
Dahlia NPL Staging Area
Site Description
The Chemical Sales Company site is located in a predominantly light industrial area in
northeast Denver and covers approximately 3 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 were installed between
1976 and 1977. There have been two 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.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 06/24/88
T\
Threats and Contaminants
High concentrations of volatile organic compounds (VOCs) were detected
in groundwater samples. Sampling of a nearby drainage ditch by the
Colorado Department of Health detected the solvents methylene chloride
and chloroform. The EPA detected trichloroethylene (TCE) in soil in the
northwest corner of the Chemical Sales Company site. Potential health
risks may 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 surface
aquifer. Sand Creek is located near the site but is not affected by the
observed contamination.
March 1990
NPL HAZARDOUS WASTE SITES
10
continued
-------
CHEMICAL SALES COMPANY
Cleanup Approach
The site is being addressed in three stages: immediate actions and two long-term
remedial phases focusing on controlling the source of contamination and cleanup of the
groundwater.
Response Action Status
Immediate Actions: 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 monitoring, Chemical Sales initiated an
investigation in 1989 to determine where the contamination is coming
from at the site and to identify alternative technologies to control the
sources of the contamination. Once this study is completed, the EPA will review the
study findings and select a cleanup strategy for site surface contamination.
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. The investigation and
the study to determine alternative site-specific technologies to clean up the
groundwater plume are scheduled to be completed in 1991.
Site Facts: The EPA has entered into an Administrative Order on Consent with
Chemical Sales requiring the company to conduct an investigation of site contamination
and to identify alternative technologies for the cleanup.
Environmental Progress
By removing drums containing hazardous materials and disposing of them at an
approved facility and securing the area, the EPA has significantly reduced the threat of
exposure to dangerous chemicals at the Chemical Sales Company site. Further
investigations leading to the selection of remedies for the contaminated groundwater
and control of the sources of contamination are currently under way.
11
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DENVER
COLORADO
EPAID#COD98071695| ; „
REGION 8
CONGRESSIONAL DIST. 01
Adams County
Denver
Aliases:
Alley ;
Colorado Southern Railroad
Thomas Real Estate
Rudd Investment Company
Site Description
Forty-four properties in Denver are contaminated with radioactive sands and wastes
abandoned after the collapse of the city's World War l-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 44, with 31 in the metropolitan Denver area.
These 31 areas were combined into 11 separate areas for cleanup activities including:
(1) the 12th and Quivas area, consisting of five separate properties; (2) 24 acres at 11th
and Umatilla that encompass individual properties; (3) the 1000 W. Louisiana area; (4 &.'
5) a 17-acre subsite including the Robinson Brick Company (ROBCO), located at 500 S.
Santa Fe Drive, and the adjacent Denver and Rio Grande Western (D&RGW) Railroad
property; (6) the property at 1314 W. Evans currently owned by the Mentor
Corporation, The Overland Company, and Hercules Industries; (7, 8, & 9) the "open
space" properties involved at the site including Allied Chemical & Dye Corporation,
Brannan Sand & Gravel Company, Burlington Northern Railroad property, Denver Water
Department land, and others; (10) a section of nine Denver streets; and (11) the
property at 1805 S. Bannock that consists of Shattuck Chemical Company and the
adjacent railroad property.
Site Responsibility: This site is being addressed through
Federal and State actions.
NPL LISTING HISTORY
Proposed Date: 10/23/81
Final Date: 09/08/83 •
Threats and Contaminants
The soil is contaminated with radium, thorium, and uranium. Although the
immediate threat to public health and the environment is limited,
redevelopment of contaminated properties or further dispersal of the
wastes could increase the exposure risk if the contaminated material is
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 could pose a health risk.
March 1990
NPL HAZARDOUS WASTE SITES
12
continued
-------
DENVER RADIUM SITE
Cleanup Approach
This site is being addressed in twelve stages: emergency actions and eleven long-term
remedial phases focusing on cleanup of the identified contamination areas and
properties. Some of these separate units contain multiple long-term remedial phases.
Response Action Status
Emergency Actions: In 1985, EPA emergency workers arrived at an
appliance refurbishing facility to remove radon gas from between the
walls. They installed a wall with 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.
12th and Quivas Properties: In 1987, the EPA selected a remedy for this
portion of the site including: (1) excavating the contaminated soil lying in
open areas and under several structures on the properties; and (2)
. transporting the soil to a permanent disposal site. Cleanup activities began
in 1989. Workers expect to excavate 22,500 cubic yards of contaminated soil and
backfill with clean soil, regrading to the original contours. Where buildings were
constructed over contaminated soil, cleanup workers will remove the floors to excavate
underlying wastes, and then replace the floors. Cleanup is scheduled to be completed
in 1990.
11th and Umatilla Properties: The EPA selected a remedy for the area in
1987. Features of the remedy are: (1) excavating contaminated soil from
open areas and from under buildings; (2) decontaminating the roof in the
Rocky Mountain Research Building; and (3) disposing of.the contaminated
material at a permanent disposal facility. Several contaminated buildings will be either
decontaminated or demolished. The EPA anticipates that 150,000 tons of
contaminated material will be removed from the property and replaced with clean fill.
The U.S. Bureau of Reclamation is managing the transport and disposal of the wastes.
1000 W. Louisiana Properties: The EPA selected a remedy for this
portion of the site in 1987. The remedy includes: (1) cleaning up the
Creative Illumination property; (2) excavating the contaminated soil
remaining on the 1000 W. Louisiana properties; and (3) removing the
contaminated material from both properties to the permanent disposal
facility. The wastes will be brought to the rail spur where workers will load them into
sealed rail cars for transport to a federally approved facility in western Utah. Workers
erected a construction fence around the vacant lot in 1988 and began storing the
contaminated dirt in barrels. More cleanup activities began in 1989, starting with the
demolition of the contaminated brick building at 1298 S. Kalamath Street Workers will
excavate 51,000 cubic yards of contaminated soil, and they will either clean up or
demolish contaminated buildings. Where waste-bearing soils extend under the streets,
workers may dig them up, remove the contamination, and repave the streets. The U.S.
Bureau of Reclamation is managing the transport and disposal of all wastes from the
Denver Radium site.
continued
13
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DENVER RADIUM SITE
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 features: (1) removing contaminated soil from the
Robinson Brick Company property and the D&RGW Railroad property; (2)
demolishing the contaminated laboratory and office buildings on the ROBCO property
and removing 200 cubic yards of debris; and (3) disposing of the contaminated soil and
debris at a permanent disposal facility. The EPA began two separate cleanup activities
at these subsites in 1988. Over 70,000 tons of contaminated waste have been
excavated and safely disposed of.
Open Lands: The EPA selected a remedy for the open lands in 1987
before the permanent disposal site had been found. It featured: (1)
capping 290 cubic yards of contaminated material, and (2) removing 1,020
cubic yards of wastes and temporarily storing them. The EPA is scheduled
.^ _ —. —. —. —. ->~4'o4 W XX I V V W—' UW^* V«< I l^r* l**s I • tf*r ** • v •• J v ».»••• • • • ^ _.-—-.-- ..._
to begin three separate cleanup activities on these properties in 1990.
Denver Streets: In 1986, the EPA chose a remedy for several Denver
street segments where the subsurface contains contaminated paving
materials. The remedy selected is to leave the contaminated material in
i , place; however, institutional controls governing routine maintenance,
repair, and construction activities in the affected streets will be set up to ensure that
the area is not disturbed or developed, and to remove and properly dispose of any
contaminated material excavated. The State has taken the lead on developing
institutional controls that will protect human health and the environment.
Shattuck Chemical Property: The EPA has provided funding to the State
to conduct an in-depth investigation of the pollution problems at Shattuck
Chemical Company and the neighboring railroad property. The study will
explore the nature and extent of site contamination and recommend the best strategies
for cleanup. It is scheduled for completion in 1991.
Card Property: The EPA selected a remedy for this subsite in 1987
featuring: (1) excavating 4,000 cubic yards of contaminated soil and
.. sediments from the Card property; (2) storing this waste in reinforced
synthetic bags placed inside the True Truss building and inside possible additions to the
building; (3) possibly staging or storing wastes from other subsites on the Card
property, but not more than 13,000 cubic yards total; (4) removing all contaminated
material to a permanent disposal facility; and (5) decontaminating and dismantling the
True Truss building and disposing of the material in a sanitary landfill. The EPA began
cleanup activities at this subsite in 1988 and completed them in 1989. Over 15,000
tons of contaminated soils were removed from this area and transported to the disposal
facility.
Environmental Progress
Extensive cleanup work has been completed'atthe Denver Radium Site, including the
removal and safe disposal of over 85,000 tons of contaminated materials. Additionally,
cleanup action has addressed immediate sources of radon and protected workers from
long-term exposure. Many additional actions are under way and planned at the Denver
Radium Site that will continue to reduce sources and levels of contamination^
14
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EAGLE MINE
COLORADO
EPA.ID# COD081961518
r
REGION 8
CONGRESSIONAL DIST. 03
Eagle County
8 miles west of Vail
Aliases:
New Jersey Zinc, Inc.
Oilman
Site Description
The 235-acre Eagle Mine site includes the Eagle Mine workings, the town of Gilman,
the mine tailings pond areas, Rex Flats, Rock Creek Canyon, and waste rock and
roaster piles. Over the last 100 years, zinc miners deposited about 7 million tons of
mine wastes and mill tailings along the Eagle River. Mining conditions and wastes from
acid, which leaches toxic metals into surrounding surface water and groundwater. Five
major sources of contamination have been identified at the site: (1) ponds containing
tailings (mining wastes) cover a total of 107 acres; (2) roaster piles, five of which are
found at this site; (3) a 25-acre pipeline corridor that extends from Rex Flats to the new
tailings pond; (4) twelve major waste rock piles that cover about 93 acres; and (5)
groundwater that has been flooding the lower levels of the mine. Access to one of the
local wilderness areas runs through the site and next to the old tailings pond. The
closest residence to the Eagle Mine site is 1,000 feet to the northeast. Minturn, the
closest population center, has 1,500 people and its filter ponds and municipal wells lie
2,000 feet northwest of the mine tailings and across Cross Creek. Minturn draws its
public water supply both from area wells and from the Eagle River.
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
Soil, surface water, and groundwater in the lower levels of the mine
contain various heavy metals including arsenic, cadmium, chromium,
copper, lead, and mercury as well as uranium. Fish populations have
declined in the reaches of the river next to mine waste areas. Water from
the three private wells located downgradientfrom the Eagle Mine;site ;
could pose a health risk if used for human consumption. One wetland
area, Maloit Park, located adjacent to the new mine tailings pile, may be
affected by surface water and groundwater flowing from the pile.
March 1990
NPL HAZARDOUS WASTE SITES
15
continued
-------
EAGLE MINE
Cleanup Approach
This site is being addressed in two stages: initial and emergency actions and a long-
term remedial phase focusing on cleanup of the entire site.
Response Action Status
Initial and Emergency Actions: Between 1976 and 1979, the mine
owners undertook early cleanup activities such as treating mine water,
revegetating 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 samp and liming
facility between the old tailings pond and the Eagle River. A mining shaft that held
transformers containing polychlorinated biphenyls (PCBs) was threatening to.erode and
spread contaminants throughout the lower mine levels and to the Eagle River. 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 under way. They also
constructed dikes in the mine to divert water from the upper mine areas and to prevent
its release.
Entire Site: In 1988, the State selected a remedy for cleaning up the
sources of pollution at the site featuring: (1) plugging the mine portals; (2)
removing the roaster piles. Rex Flats tailings, and tailings pile and
consolidating themjn the "new" tailings pile; (3) capping the new pile and
pumping groundwater; and (4) monitoring the Eagle River. Surface and groundwater
collected at the tailings piles will be pumped to the Eagle Mine workings. To prevent
discharge of contaminated water to the river from the mine, the former owners have
constructed two concrete bulkheads in mine openings and are planning to build several
more on its property. A temporary lime treatment system has been constructed at the
old pond to neutralize runoff prior to discharge to the river. Under State monitoring, the
former mine owners have plugged the mine and reworked many millions of cubic yards
of mine tailings. They are consolidating wastes from the roaster piles, Rex Flats, and
the old tailings pile into the new tailings pile, and controlling groundwater in the area.
Workers are preparing to cap the tailings. The cleanup actions are scheduled to be
completed in 1994.
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.
However, the EPA has determined that metal-contaminated acid mine drainage
currently threatens the Eagle River. The EPA plans to continue treating water drainage
and to monitor river impacts while long-term remedial actions are under way to protect
the Eagle River from contaminated runoff from the site.
16
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LINCOLN PAR&
COLORADO \ ?
EPAID# COD042167858
REGION 8
CONGRESSIONAL DIST. 03
Fremont County
Canon City
Aliases:
Uranium Mill
Cotter Corporation
Site Description
Beginning in 1958, the Cotter Corporation operated a uranium mill approximately 1 1/2
miles from the 410-acre Lincoln Park site. Mill operations caused the release of
radionuclides and heavy metals into the environment. Contaminants migrated
downstream to Lincoln Park prior to the construction of a dam on Sand Creek. The
groundwater was found to be contaminated. There are several drinking water wells in
the area. Many residents have stopped using groundwater for domestic purposes and
have been connected to the Canon City water supply; however, some individuals in
Lincoln Park are still using groundwater. 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 site has been shown to be contaminated
with uranium and other radionuclides. Soils on the plant site are also
contaminated with similar uranium products. People who drink or touch
contaminated well water may suffer adverse health effects.
March 1990
NPL HAZARDOUS WASTE SITES
17
continued
-------
LINCOLN PARK
Cleanup Approach
This site is being addressed in a single long-term remedial phase focusing on cleanup
of the entire site.
Response Action Status
Entire Site: In 1988, the State, with the EPA's approval, selected! a
remedy to clean up the site by: {1} placing area residents on an alternate
water supply; (2) pumping and treating the groundwater above the dam on
Sand Creek to remove the contaminants; (3) flushing the contaminants out
of the water below the dam; (4) revegetating the site; (5) implementing air quality
controls; and (6) stopping off-site groundwater migration. The company is designing
the technical specifications to treat the groundwater. All of the design phase is
scheduled to be completed in 1990. To date, the Cotter Corporation has contained the
contaminants from the uranium mill by a groundwater cut-off barrier and then pumping
the water back into holding ponds.
Site Facts: In 1987, the State and the Cotter Corporation signed a Consent Decree
under which Cotter will clean up the contamination at the site.
Environmental Progress
Preliminary containment measures have been taken at the Lincoln Park site to prevent
uranium-contaminated groundwater from migrating off site. Currently, the design for
the cleanup remedies is under way that will restore the site to environmentally safe
levels.
18
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LOWRY LAN
COLORADO
EPA ID# COD9804!
REGION 8
CONGRESSIONAL DIST. 04
Arapahoe County
2 miles east of Aurora
Aliases:
Lowry Disposal Area
City and County of Denver Landfill
Conoco City and County of Denver Landfarm
Denver Arapahoe Disposal
Site Description
The Lowry Landfill covers approximately 400 acres near Aurora, a suburb of Denver. It
is estimated that 71 million gallons of liquid industrial wastes were dumped into 65
unlined trenches or pits in the /anc/f/7/from 1966 until 1980. This waste 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 waste 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.
Chemical Waste Management, Inc. took over the operation of the landfill and undertook
a preliminary cleanup in 1980. The wastes have migrated into the groundwater and
surface water. Liquid wastes that reached the land surface have formed a heavily
contaminated stream flowing at peak rates of 16,500 gallons per day. Surface water
runoff and liquid wastes from the site drain into an unnamed creek that flows into a
holding pond. The unnamed creek is intermittent and flows to the north into Murphy
Creek which crosses farmland and various subdivisions before flowing into Sand Creek,
and from there into a tributary of the South Platte River. 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.
NPL LISTING HISTORY
Proposed Date: 09/08/83
Final Date: 09/21/84
Threats and Contaminants
T\
The air, shallow groundwater, sediments, soils, and surface water contain
organic chemicals, radionuclides/lortizinQ radiation, and inorganic
chemicals. Although the shallow groundwater is contaminated, it is not
used for drinking water sources. If the landfill is not cleaned up, the
potential exists for the contaminants to migrate into the deep
groundwater, the source of drinking water in the area. The EPA has
determined that the site does not pose any immediate risks to human
health.
March 1990
NPL HAZARDOUS WASTE SITES
19
continued
-------
LOWRY LANDFILL
Cleanup Approach
The site is being addressed in six stages: initial actions and five long-term remedial
phases focusing on cleanup of the groundwater, landfill solids, landfill gases, soils, and
surface water and sediments.
Response Action Status
Initial Actions: In an initial action in 1984, the City and County of Denver
constructed an underground barrier wall and treatment system. The wall
. functions as a dam to contain and collect shallow groundwater 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. In 1989, Denver began to shred the discarded tires that are stockpiled at
the site. The shredding is expected to be completed by 1990. The EPA has
determined that drums containing wastes from site sampling are currently deteriorating
and threaten to release contaminated materials. An additional action is planned to bulk
and remove the drum contents and discharge liquids to a wastewater plant.
Groundwater: In 1989, the Lowry Coalition, under EPA guidance, began
studying the deep groundwater beneath the site to determine the extent
, ^ of the contamination. This study is being performed in conjunction with
the shallow groundwater study. Completion is expected in 1992.
Landfill Solids: In 1990, the City of Denver, Waste Management of
Colorado, and Chemical Waste Management began a study, under EPA
{ monitoring, of the solid refuse disposed of at the site. This includes the
buried drums, tires, and other debris in the waste pit area. Once this study is
completed in 1993, effective measures will be recommended to clean up the refuse.
Landfill Gas: In 1990, the City of Denver, Waste Management of
Colorado, and Chemical Waste Management began a study of the gas
accumulating in the landfill. This study will investigate methane and other
., gases generated at the site and determine the extent contaminant vapors
may have migrated from the landfill. This study is scheduled to be completed in 1993.
Soils: The potentially responsible parties will investigate, under EPA
monitoring, the extent of soil contamination. This investigation is
expected to begin in 1991.
Surface Water and Sediment: After 1991, the potentially responsible
parties will study the extent of the surface water and sediment
contamination both on and off the site.
Site Facts: In 1988, the EPA and 13 parties potentially responsible for the site
contamination, who refer to themselves as the Lowry Coalition, reached an agreement
to clean up the site.
continued
20
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LOWRY LANDFILL
Environmental Progress
By constructing an underground barrier wall and treatment system, the City and County
of Denver have contained the contaminated shallow groundwater and have prevented it
from migrating off the site to cause further pollution. Additionally, a removal of
deteriorating drums is planned as an interim measure to protect the environment while
site investigations are conducted. Various investigations are currently under way, or are
planned to begin in the very near future, to evaluate the extent of the contamination in
the groundwater, surface water, and sediments. These studies will result in the
selection of final remedies for all the affected areas of Lowry Landfill.
21
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MARSHALL
COLORADO
EPAID# COD98049925
REGION 8
CONGRESSIONAL DIST. 02
Boulder County-
Town of Marshall
Site Description
The Marshall Landfill, covering 400 acres, is immediately south of Colorado Highway
170 and is bounded on the east by South 66th Street.,, Marshall Reservoir is upstream
of the site about 2,000 feet to the west. The site is divided into two adjacent sections;
the first is an inactive 80-acre section which served as a landfill and the second is a 80-
acre section actively serving as a privately owned and operated landfill. Between 1965
and 1974, the inactive landfill accepted unstabilized sewage sludge and many,
unidentified and potentially hazardous wastes. Septic wastes and possibly liquid
industrial wastes were also disposed of off site in two septic ponds. The ponds are
now closed The active landfill has accepted sewage sludge and municipal waste since
1974 Before 1978, landfill leachate was observed seeping into the community ditcn
that carries drinking water from nearby Marshall Lake to the City of Louisville and
serves as irrigation water for a reservoir and irrigation company.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties' 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 surface waters on
the site. Drinking contaminated groundwater could present a health
threat to individuals.
March 1990
NPL HAZARDOUS WASTE SITES
22
continued
-------
MARSHALL LANDFIIX
Cleanup Approach
The site is being addressed in two stages: immediate actions and a long-term remedial
phase focusing on cleanup of the groundwater and surface water both on and off site.
Response Action Status
* Immediate 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 technologies to address VOC and inorganic
chemical contamination include: fencing, regrading, and planting of the
northern portion of inactive landfill; installing a groundwater collection and
treatment system {allowing some contaminants to settle out, exposing the
groundwater to air to allow contaminants to evaporate and recapturing the
contaminants in a carbon filter before releasing the air), and discharging the treated
water to Cowdrey Drainage; monitoring groundwater and surface water; and landfill
improvements, including regrading, revegetating, digging of perimeter ditches, and
installing fences. The potentially responsible parties, under EPA monitoring, are
preparing the technical specifications and design for the selected cleanup technologies
in two phases. The first phase, which includes fencing, regrading, and vegetating the
northern section of the inactive landfill, was completed in 1989 and the cleanup actions
are expected to be completed in 1990. The remaining cleanup activities are included in
the second design phase, with cleanup activities scheduled to be completed in 1991.
Site Facts: Pursuant to an Enforcement Order in 1984, Landfill, Inc. installed a
pressurized pipeline to protect drinking water supplies. The EPA negotiated Consent
Decrees with the parties potentially responsible, including the City of Boulder, Landfill
Inc., and the Cowdrey Corporation.
Environmental Progress
Protective measures have been taken to ensure the safety of the local drinking water
supply and work completed that restrict access and prevent further degradation of the
site. These actions have reduced the potential for exposure to site contamination while
the permanent groundwater treatment system is designed and constructed.
23
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FLATS
ROCKY
(USDOE)
COLORADO
EPAID# CO7890010526
REGION 8
CONGRESSIONAL DIST.
Jefferson County
16 miles northwest of Denver
Site Description
The Rocky Flats site covers 6,550 acres of United States Department of Energy
(USDOE) land Originally established by the Federal Government in 1951, the facility is
still in operation under contractor management. Rocky Flats produces plutonium
triqqersforthe USDOE nuclear weapons program. Site operations include recovering
and reprocessing plutonium from old weapons and manufacturing residues, laboratory
research, and the manufacture of "high-tech" metals, many of which continue to
generate a variety of waste streams on site. Many of the manufacturing and pollution
control facilities that originally operated at the site have been upgraded from their
oriqinal construction and are still used in the USDOE's nuclear weapons production .
Droqram 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
include 107 disposal areas resulting from past waste management practices; a series of
evaporation surface impoundments; old process pipelines and underground tanks; an
aqueous spray irrigation field; an on-site landfill; leaking drum storage areas, and several
disposal trenches. Approximately 9,500 people live within a 5-mile radius of the
industrial complex.
Site Responsibility: This site is being addressed through
Federal and State actions.
NPL LISTING HISTORY
Proposed Date: 10/15/84
Final Date: 10/04/89
Threats and Contaminants
Air is a potential contaminant pathway for migration of radioactive
plutonium uranium, and americium. Groundwater contains various
volatile organic compounds (VOCs}, radionuclides, and heavy metals. Soil
and surface water contain plutonium, uranium, and americium. People
could be exposed to chemicals on site by touching, inhaling,.or r . -
accidentally ingesting contaminants in soil, air, groundwater, and surface
water. Shallow groundwater in the southern section of the site (the
Hillside area) is contaminated with VOCs which are excessively high for
this area. :
March 1990
NPL HAZARDOUS
24
'ASTE SITES
continued
-------
ROCKY PLATS PLANT (USDOE)
Cleanup Approach
This site is being addressed in five stages: an immediate action and four long-term
remedial phases focusing on: source control; the Hillside areas; the 903 Pad area, East
Trenches, and Mound Areas; and the remaining 47 lower priority areas surrounding the
site.
Response Action Status
Immediate Action: In 1987, the EPA removed more than 20,000 cubic
yards of sludge from evaporation ponds and conducted dewatering
operations.
Source Control: The EPA continues to operate a collection system for
contaminated groundwater. This has effectively contained the
contaminants until further action can be taken to assess and clean up soils
and groundwater. • .. .
Hillside Areas: In 1988, the USDOE completed the draft reports about
the nature and extent of contamination in the 12 subsites within the
Hillside 881 area. Cleanup actions have been started that are intended to
stop contaminants from moving through the groundwater through the use of a french
drain system and a groundwater pump and treat system. The USDOE began cleaning
up the groundwater in 1990.
903 Pad, East Trenches, and Mound Areas: In 1988, the USDOE
submitted plans to sample this area. This area, comprised of 18 subsites,
is the most complex and difficult to address on the site due primarily to
the high concentrations of radioactive contaminants that must be cleaned up, as well as
surface water seeps which will require interim measures. Several interim measure
options are currently being developed.
Remaining 47 Lower Priority Areas: The USDOE will conduct a study
into the nature and extent of the remaining low priority areas around the
Rocky Flats site and will select alternate cleanup technologies to address
these areas. When this study is completed, the EPA will select final site cleanup
remedies, and the USDOE will begin cleanup activities.
Site Facts: A Federal Facility Compliance Agreement (FFCA) to achieve compliance
with the land disposal restrictions went into effect in 1989 at Rocky Flats. The EPA
issued an order to Rockwell International in 1989 requiring them to identify the scope
of the problem at Rocky Flats. The USDOE, the EPA, and the State have divided the
site into 16 cleanup areas under an Interagency Agreement
Environmental Progress
The removal of contaminated sludge and the dewatering operation have effectively
contained the spread of contaminants. The cleanup of contaminated groundwater
resources at the Rocky Flats site has begun and further cleanup activities are planned
that will eliminate the potential for exposure to hazardous substances at the site
25
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ROCKY
ARSENAL
COLORADO
EPA ID# CO5210020769
REGION 8
CONGRESSIONAL DIST. 04
Adams County
10 miles northeast of downtown Denver
Alias:
Shell Chemical Company
Site Description
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 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. Industrial
effluents generated at the arsenal were routinely discharged to unlined evaporation
basins. Solid wastes were buried at various locations. Spills of raw materials and final
products occurred within the manufacturing complexes. Munitions and pesticide
operations over 40 years led to spills and the disposal of more than 750 different
hazardous wastes in several areas. All production operations ceased at the site 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. It now holds about 10 million
gallons and 564,000 cubic yards of solids. Five unlined basins received wastes before
Basin F was built. The site also contains an incinerator, processing, storage, and
supporting operations and two major industrial complexes that produced pesticides, ••
nerve gas, and mustard gas. There are also numerous waste piles, burial trenches, and
abandoned munitions storage areas on site. On-site groundwater, which is not
currently being used, is contaminated in both the alluvial and bedrock aquifers. Old
livestock wells on site are being plugged and abandoned. Groundwater intercept
systems have been installed to remove the contaminants. Three plumes of
contaminated groundwater migrated off site before the intercept systems were
installed. Surface streams near the arsenal may be receiving contaminants frorfi
groundwater discharge. Plumes of contaminated groundwater eventually discharge1
into the South Platte River. Stapleton Airport abuts the southwest corner of the site.
The South Adams County Water and Sanitation District was created in 1953 to supply
approximately 30,000 customers with well water from the aquifers.
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: 07/01/87
March 1990
NPL HAZARDOUS WASTE SITES
26
continued
-------
ROCKY MOUNTAIN ARSENAL
Threats and Contaminants
On-site groundwater is contaminated with various volatile organic
compounds (VOCs). Sediment samples 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 breakdown products from warfare agents. The health
threats to people associated with this site include inhaling of
contaminated dusts that result from cleanup activities, accidental
ingestion of contaminated soils, and eating contaminated plants and
animals. Homes affected by contaminated drinking water were supplied
with alternate water.
Cleanup Approach
This site is being addressed in twenty-six stages: initial actions and twenty-five long-
term remedial phases focusing on the contamination areas identified at the site.
Response Action Status
Initial Actions: Shell Chemical Company installed the Irondale
groundwater treatment system in 1981. The installation of the the North
Boundary groundwater treatment system was completed in 1982. Liquids
were evaporated and the contaminated sewer was removed from Basin F in 1982. In
1984, the Northwest Boundary groundwater treatment system was completed. Over
76,000 drums of waste salts were removed in 1986.
South Adams County Public Water Supply: The EPA installed a
granular activated carbon water treatment system in 1986. The system
opened in 1989 as the Klein Water Treatment Plant and is located adjacent
to the arsenal.
system.
The following phases are in the engineering design stage and are
scheduled for completion in 1992: M-1 ponds vitrification design; motor
pool area vapor extraction system; Pail Classification Yard groundwater
intercept and treatement system; and Lime Settling Basins containment
The following cleanup activities are scheduled for completion in 1991:
groundwater intercept and treatment system of Basin F and Basin A Neck
areas construction; hydrazine facility for disposal of liquid wastes and
cleanup/dismantling of the facility; windblown dust control reapplication;
sanitary sewer closure; and asbestos removal from the building.
Aquifers: The investigation determining the nature and extent of
contamination continues under the jurisdiction of the Chemical Sales
Company NPL site.
continued
27
-------
ROCKY MOUNTAIN ARSENAL
Response Action Status - continued
On-Site Contamination and Off-Site Contamination phases are
investigating the type and extent of contamination. The investigations
will include alternatives for final cleanup and are scheduled for completion
in 1992 and 1993.
Groundwater Intercept and Treatment System: The technical
specifications for the groundwater intercept and treatment system off site
north of the arsenal is expected to be completed in 1991.
North Boundary System: Recharge trenches were installed at the North
Boundary System. The first stage of improvements were made to the
.. system in 1988, and the second stage improvements are continuing With
completion expected in 1990. Engineering design for three new intercept and
treatment systems located north of Basin F and off post, north of the site, were also
completed in 1989.
Abandoned Wells: Approximately 344 abandoned wells on post were
sampled, closed, and plugged in 1990.
Contaminated Liquids and Sludges from Under Basin F: Basin F was
closed in 1989. Approximately 10 1/2 million gallons of liquid and 564,000
cubic yards of contaminated sludges have been removed and placed in
temporary storage.
Contaminated Liquids in the Building 1727 Sump: The operations and
maintenance of the sump are expected to continue through 1993.
Wastewater: The development and use of a program to treat. .
wastewater resulting from other cleanup actions are scheduled for 1991
South Tank Farm: The South Tank Farm plume is under investigation
and an interim document allowing activities to occur, pending a final
decision on cleanup actions, is expected in 1993.
Army Trenches: A monitoring plan is being developed and is expected
to be completed in 1993.
Shell Trenches: The design of the containment system is ongoing and is
scheduled for completion in 1993.
Continued
28
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ROCKF MOUNTAIN ARSENAL
Response Action Status - continued
Northwest Boundary System: Improvements are ongoing and the first
stage is expected to be completed in 1990. An interim document
allowing site activities to continue, pending a final remedy, is expected for
-the second stage in 1992.
Treatment of Basin F Liquids: The design of the incinerator for the
treatment of the liquids is underway, with completion expected in 1992 or
1993. The selected cleanup technologies used to treat the contaminated
groundwater include: construction of a granular activated carbon water.
treatment system and regeneration of spent carbon at another location; modification of
the system to include an air stripping facility to treat vinyl chloride, if necessary;
replacement of existing well pumps and motors; installation of transmission piping; and
construction of laboratory and office space to ensure that the remedy operates
effectively.
Site Fact's: In 1982, the EPA initiated a Memorandum of Agreement wi.th the Army,
the State, and SheH 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 (FFA). The new agreement superseded
the Memorandum of Agreement, apportioned liability between Shell and the Army and
resolved the Army-Shell litigation.
Environmental Progress
The closing of the site, removal of contaminants, and the provision of an alternative
water supply have greatly reduced the potential for exposure to contaminated materials
at the Rocky Mountain Arsenal site. Further studies and cleanup actions are being
performed, at the various areas that comprise this site.
A
29
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SAND CREEK
INDUSTRIES
COLORADO
EPAID# COD980717953
REGION 8
CONGRESSIONAL DIST. 04
Adams County
Commerce City
Aliases:
L C Corporation
Colorado Organic Chemical Company
E. Holly & 48th St. Landfill
Browning Ferris/Globe Chemical
Colorado International Corporation
Private Brands Western, Inc.
Site Description
The 500-acre Sand Creek Industrial site consists of four known potential sources of
contamination, all of which are now inactive: the Oriental Refinery the Colorado
Organic Chemical (COC) 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, an explosion in a trench which killed two men, an
incident in which livestock were severely burned when they wandered into acid pits, _
and a fire at the pesticide formulator, which 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 COC plant originally manufactured pesticides in
the 1960s Since 1968, when a fire destroyed three of the buildings on site, several
health aqencies have found unacceptable conditions at the plant. These have included
unsatisfactory waste management practices and worker safety conditions violations in
storage and handling of flammable liquids, and soil containing, high leve s^ 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 rubber-lined pits.
After the livestock were burned, lime was added and the pit area was covered. Acid
was found to be seeping from the pits into Sand Creek in 1976. In 1980 L.L.
Corporation covered the seepage with clean soil. The 48th Street and Holly Landdl
was used to dispose of municipal wastes. Less 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
March 1990
The EPA conducted sampling at the site and found the soil, groundwater,
and surface water to be contaminated. Waste was discharged into Sand
Creek Groundwater is contaminated with various volatile organic
compounds (VOCs) as well as heavy metals including cadmium, nickel,
and arsenic. Soil is contaminated with VOCs, pesticides, herbicides, and
arsenic Sand Creek is contaminated with heavy metals including
cadmium, nickel, and arsenic. People who accidentally touch or ingest
contaminated groundwater, surface water, or soil may suffer adverse
health effects. In addition, people on site may be exposed by inhaling
contaminated dust or vapors from the soil.
NPL HAZARDOUS WASTE SITES
30
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SAND CREEK INDUSTRIAL
Cleanup Approach
This site is being addressed in six stages: initial actions and five long-term remedial
phases focusing on cleanup of: COC soils and structures, L.C. Corporation Acid Pits,
48th Street and Holly Landfill, groundwater contamination, and gas at the Holly Landfill.
Response Action Status
Initial Actions: In 1984, COC removed waste drums and contaminated
'soil and fenced the area. In 1988, the EPA removed two tanks and five
drums containing pesticides and transported them to federally approved
facilities. In addition, a synthetic cover was placed over the contaminated soil to
prevent erosion and vapor emissions.
COC Soils and Structures: In 1989, the EPA selected a remedy to clean
up the COC soils and structures by: excavating the contaminated soil and
incinerating it off site; extracting the VOCs from the surface soil with
vacuum pressure, demolishing the contaminated tanks and buildings and
disposing of them in a federally approved facility; and treating 38,000 cubic yards of
surface soil by either biological treatment or soil washing. The EPA is designing the
technical specifications for the cleanup of the soils and the structures at COC. The
design phase is scheduled'for completion in 1990, after which cleanup activities will
begin. The EPA has decided to conduct additional studies to determine if biological
treatment or soil washing is the most effective treatment for the surface soils.
L.C. Corporation Acids Pits: In 1990, the L.C. Corporation, under EPA
monitoring, is scheduled to conduct studies to determine the type and
extent of the acid in the pits and the surrounding area.
48th and Holly Landfill: In 1991, the EPA is scheduled to conduct an
investigation to determine the extent of the contaminants in the 48th and
Holly Landfill and to identify alternative technologies to clean UD the area.
Groundwater: In 1991, the EPA is scheduled to conduct extensive
studies of the groundwater in the area to determine if there is a need for
groundwater cleanup activities.
Gas at Holly,Landfill: In 1990, the EPA plans to take action to investigate
methods to reduce the gas emissions emanating from the Holly Landfill.
Site Facts: In 1984, the EPA issued an Administrative Order to COC to remove waste
drums, contaminated soil, and to fence the area.
Environmental Progress
The removal of drums, contaminated soil, and the fencing of the area, as well as early
actions taken by the site owners, have reduced the potential for exposure to
contaminated materials at the Sand Creek Industrial site while further investigations
and cleanup activities are taking place. ^
31
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SMUGGLER
COLORADO
EPAID# COD980806277
REGION 8
CONGRESSIONAL DIST. 03
Pitkin County
1 mile northeast of Aspen
Site Description
The 75-acre Smuggler Mountain site is an inactive silver and lead mining site that was
in operation from 1879 to 1918. Mine tailings from the site and mines in the area as
well as ancillary smelting and milling operations, 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 mineral exploration activities are still
conducted on site. Tailings and mine wastes spread downhill and mixed with native
soil ore-bearing rock, and miscellaneous fill material. The total volume of waste 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 waste piles have been moved to the
sides of developed areas and remain as berms or mounds of contaminated soil.
Portions of contaminated soil have also been used for fill in some areas. The site is
near the City of Aspen, which has a year-round population of approximately 4,500 as
well as seasonal tourists. The City of Aspen obtains drinking water from surface
waters in the area. The nearest surface water is the Roaring Fork River, approximately
1,000 feet downstream from the site. Groundwater is used for drinking water, and two
private wells are located along the site.
Site Responsibility: The site is being cleaned up through
a combination of Federal and
potentially responsible parties'
actions.
IMPL 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 drinking and
touching contaminated groundwater, or accidentally eating or touching
contaminated surface soils or vegetables grown in contaminated soils.
The Roaring Fork River is not likely to be a potential health risk-to people.
A potential health risk may exist for area residents using groundwater as
the sole source of potable water.
March 1990
NPL HAZARDOUS WASTE SITES
32
continued
-------
SMUGGLER MOUNTAIN
Cleanup Approach
This site is being addressed in three stages: an immediate action and two long-term
remedial phases focusing on cleanup of the residential areas and cleanup of the mine
area.
Response Action Status
Immediate Action: In 1985, a party potentially responsible for site
contamination installed fencing around the site and posted warning signs
as directed by the EPA.
Residential Areas: The remedy selected by the EPA in 1988 addresses
contamination impacts to residential areas near the site including: (1)
construction of two cells for on-site disposal of waste materials and
relocation of the pipeline that passes through the Mollie Gibson Park
repository; (2) excavation of the top levels of soils and tailings in areas with high lead
concentrations, which will be overlain with a geo-textile liner, backfilled with clean fill,
covered with topsoil, and revegetated; (3) provision of a permanent, alternate water '
supply by closing groundwater wells for five to seven residences and connecting the
residences to the existing public water supply; and (4) operation and maintenance of
the repositories to preserve the integrity of an existing tailings cap within the residential
areas. The EPA is currently designing the technical specifications for the selected
remedies. The design phase is scheduled to be completed in 1990. An irrigation
pipeline is scheduled to be relocated in 1990 in order to prepare the repository.
Cleanup on the properties is scheduled to begin in 1991 and is expected to continue
into 1992.
Mine Area: The EPA currently is conducting an additional study of the
nature and extent of contamination at the Smuggler-Durant Mine area,
including possible contamination of groundwater,underlying the site. The
study will define the contaminants and will recommend alternatives for
final cleanup.
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, investigate site contamination and
recommend alternatives for final cleanup, and provide for the fencing and securing of a
portion of the site to prevent public access.
Environmental Progress
Initial actions such as fencing the site have restricted access to the contamination
areas, protecting the nearby public while final remedies are being designed to restore
the residential area and additional studies are undertaken at the Smuggler Mountain
33
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URAVAN URANHIMJ
PROJECT (UNION
CARBIDE CORP.)
COLORADO
EPA ID# COD007063274
REGION 8
^KESSIONAL DIST. 03
Montrose County
90 miles southwest
of Grand Junction
Aliases:
in Uranium Mill Operations
avan Uranium Mill Town
UMETCO
Site Description
The Uravan Uranium site began as a radium recovery plant in 1915. The plant
expanded to include vanadium recovery in 1935 and began production in 1936. The
town of Uravan was established in 1935 to house the workers at the mill and mine
facilities The plant operated from the late 1940s as a uranium processing facility. In
1984 Union Carbide formed a wholly-owned subsidiary, UMETCO, which now owns
and operates the facility. During the history of operations at the site, a large volume ot
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. Uravan is one of the more complex radiation sites in the country,
with heavy metals, residual salts, and radionuclide contamination of groundwater and
surface water. Radon gas emanates from the eroding tailings piles. The Town of
Uravan 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
Ambient a/rat the site contains elevated levels of radon gas.
Groundwater and surface water contain radionuclides and heavy metals.
Before the town was relocated, potential exposure to radionuclides posed
a much greater threat to human health.
March 1990
NPL HAZARDOUS WASTE SITES
34
continued
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URAVAN URANIUM PROJECT (UNION CARBIDE CORP.)
Cleanup Approach
This site is being addressed in a single long-term remedial phase focusing on cleanup
of the entire site.
Response Action Status
Entire Site: The State completed a plan to clean up contamination at the
site in 1986. The features of this remedy include: (1) reclaiming nearly 10
million tons of radioactive tailings by capping and revegetation; (2)
constructing a disposal system for radioactive crystals; (3) placing 1 1/2
million cubic yards of waste found along the San Miguel River in a secure disposal area-
(4) excavating contaminated soil and placing it in an approved landfill; and (5) reclaiming'
and revegetating the land on the site. The major elements of these activities are under
way and are scheduled to be completed by 1995. Union Carbide has finished
constructing 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 is also
conducting radiation surveys of the old pond area to address issues that affect the
health of workers on site before they de water the raffinate crystals from the old ponds.
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 to
find an effective remedy for the problems there.
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 relocated no
immediate actions were required at the Uravan Uranium site. Cleanup actions
presently completed or under way will restore the site to safety levels that are
protective of human health and the surrounding environment.
35
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WOODBURY QH
COMPANY
COLORADO
EPATJD# COD980667075
REGIONS
CONGRESSIONAL DIST. 04
Adams County
Commerce City
Site Description
The 5-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 1/2 mile of the site.
Site Responsibility:
This site is being addressed through
Federal and potentially responsible
parties' actions.
NPL LISTING HISTORY
Proposed Date: 07/23/82
Final Date: 09/08/83
Threats and Contaminants
L\
Sediments in a drainage ditch, surface water runoff, and soils on the site
contain chlorinated hydrocarbons, heavy metals, and pesticides. Potential
health risks may exist for individuals accidentally ingesting or touching
contaminated soils or surface water.
March 1990
NPL HAZARDOUS WASTE SITES
36
Continued
-------
WOODBURY CHEMICAL COMPANY
Cleanup Approach —
This site is being addressed in three phases: immediate actions and two long-term
remedial phases focusing on cleanup of the rubble piles and cleanup of the entire site.
Response Action Status
Immediate Actions: In 1983, to prevent public access to the site and
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.
Rubble Piles: In 1985, the EPA selected a complete cleanup remedy for
the original site 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 believed. This led to the addition of another cleanup area at the site All
contaminated soil, originally meant to be addressed in this cleanup action is now beina
addressed in the next phase. '
Entire Site: Additional cleanup work to be performed by the EPA will
include 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 federally approved landfill. The design of the
technologies to be used is scheduled to begin in 1991. This work will be conducted by
the parties potentially responsible for the contamination under EPA monitoring.
Site Facts: An Administrative Order on Consent was signed in 1987 between the EPA
and the McKesson Corporation to conduct an investigation into the contamination at
the site and to identify alternative technologies for the cleanup.
Environmental Progress
The actions to prevent access to the site and to prevent additional surface water runoff
have greatly reduced the potential for exposure to contaminated materials at the
Woodbury Chemical Company site while further investigations and cleanup activities
are taking place.
37
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-------
his glossary defines the italicized terms used in the
site fact sheets for the State of Colorado. The terms
_\ and abbreviations contained in this glossary are often
defined in the context of hazardous waste management as
described in the site fact sheets, and apply specifically to work
performed under the Superfund program. Thus, these terms
may have other meanings when used in a different context.
Acids: Substances, characterized by low pH (less than
7.0) that are used in chemical manufacturing. Acids in
high concentration can be very corrosive and react with
many inorganic and organic substances. These reactions
may possibly create toxic compounds or release heavy
metal contaminants that remain in the environment long
after the acid is neutralized.
Administrative Order On Consent: A legal and enforceable agreement between EPA
and the parties potentially responsible for site contamination. Under the terms of the
Order, the potentially responsible parties agree to perform or pay for site studies or
cleanups. It also describes the oversight rules, responsibilities and enforcement options
that the government may exercise in the event of non-compliance by potentially respon-
sible parties. This Order is signed by PRPs and the government; it does not require
approval by a judge.
Administrative Order [Unilateral]: A legally binding document issued by EPA direct-
ing the parties potentially responsible to perform site cleanups or studies (generally,
EPA does not issue unilateral orders for site studies).
Air Stripping: A process whereby volatile organic chemicals (VOCs) are removed from
contaminated material by forcing a stream of air through it in a pressurized vessel. The
contaminants are evaporated into the air stream. The air may be further treated before
it is released into the atmosphere.
Alluvial: An area of sand, clay, or other similar material that has been gradually depos-
ited by moving water, such as along a river bed or the shore of a lake.
Ambient Air: Any unconfined part of the atmosphere. Refers to the air that may be
inhaled by workers or residents in the vicinity of contaminated air sources.
G-l
-------
An underground layer of rock, sand, or gravel capable of storing water within
as ,d pore spafes, or beLen grain, When water contained within an aquifer is
of sufficient quantity and quality, it can be tapped and used for drinking or other pur-
poses. The water contained in the aquifer is called groundwater.
Backfill: To refill an excavated area with removed earth; or the material itself that is
used to refill an excavated area.
Berm: A ledge, wall, or a mound of earth used to prevent the migration of contami-
nants.
Cap: A layer of material, such as clay or a synthetic material, used to prevent rainwater
from penetrating and spreading contaminated materials. The surface of the cap is
generally mounded or sloped so water will drain off.
Cell: In solid waste disposal, one of a series of holes in a landfill where waste is
dumped, compacted, and covered with layers of dirt.
Consent Decree: A legal document, approved and issued by a judge, formalizing an
agreement between EPA and the parties potentially responsible for site contamination.
The decree describes cleanup actions that the potentially responsible parties are re-
quired to perform and/or the costs incurred by the government that the parties will
reimburse, as well as the roles, responsibilities, and enforcement options that the gov-
ernment may exercise in the event of non-compliance by potentially responsible parties.
If a settlement between EPA and a potentially responsible party includes cleanup ac-
tions, it must be in the form of a consent decree. A consent decree is subject to a public
comment period.
Containment: The process of enclosing or containing hazardous substances in a struc-
ture, typically in ponds and lagoons, to prevent the migration of contaminants into the
environment.
Cooperative Agreement: A contract between EPA and the states wherein a State agrees
to manage or monitor certain site cleanup responsibilities and other activities on a cost-
sharing basis.
Creosotes: Chemicals used in wood preserving operations and produced by distillation
of tar including polycyclic aromatic hydrocarbons and polynuclear aromatic hydrocar-
bons [see PAHs and PNAs]. Contaminating sediments, soils, and surface water, creo-
sotes may cause skin ulcerations and cancer with prolonged exposure.
Dewater: To remove water from wastes, soils, or chemicals.
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Downgradienfc A downward hydrologic slope that causes groundwater to move
toward lower elevations. Therefore, wells downgradient of a contaminated groundwater
source are prone to receiving pollutants.
Effluent: Wastewater, treated or untreated, that flows out of a treatment plant, sewer,
or industrial outfall. Generally refers to wastes discharged into surface waters.
French Drain System: A crushed rock drain system constructed of perforated pipes,
which is used to drain and disperse wastewater.
Impoundment: A body of water or sludge confined by a dam, dike, floodgate, or other
barrier.
Installation Restoration Program: The specially funded program established in 1978
under which the Department of Defense has been identifying and evaluating its hazard-
ous waste sites and controlling the migration of hazardous contaminants from those
sites.
Interagency Agreement: A written agreement between EPA and a Federal agency that
has the lead for site cleanup activities (e.g. the Department of Defense), that sets forth
the roles and responsibilities of the agencies for performing and overseeing the activi-
ties. States are often parties to interagency agreements.
Landfill: A disposal facility where waste is placed in or on land.
Leachate [n]: The liquid that trickles through or drains from waste, carrying soluble
components from the waste. Leach, Leaching [v.t.]: The process by which soluble
chemical components are dissolved and carried through soil by water or some other
percolating liquid.
Long-term Remedial Phase: Distinct, often incremental, steps that are taken to solve
site pollution problems. Depending on the complexity, site cleanup activities can be
separated into a number of these phases.
Migration: The movement of oil, gas, contaminants, water, or other liquids through
porous and permeable rock.
Pentachlorophenol (PCP): A synthetic, modified petrochemical that is used as a wood
preservative because of its toxicity to termites and fungi. It is a common component of
creosotes and can cause cancer.
Plume: A body of contaminated groundwater flowing from a specific source. The
movement of the groundwater is influenced by such factors as local groundwater flow
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patterns, the character of the aquifer in which groundwater is contained, and the den-
sity of contaminants.
Polycyclic Aromatic Hydrocarbons or Polyaromatic Hydrocarbons (PAHs): PAHs,
such as pyrene, are a group of highly reactive organic compounds found in motor oil.
They are a common component of creosotes and can cause cancer.
Polychlorinated Biphenyls (PCBs): A group of toxic chemicals used for a variety of
purposes including electrical applications, carbonless copy paper, adhesives, hydraulic
fluids, microscope emersion oils, and caulking compounds. PCBs are also produced in
certain combustion processes. PCBs are extremely persistent in the environment be-
cause they are very stable, non-reactive, and highly heat resistant. Burning them pro-
duces even more toxins. Chronic exposure to PCBs is believed to cause liver damage^ It
is also known to bioaccumulate in fatty tissues. PCB use and sale was banned m 1979
with the passage of the Toxic Substances Control Act.
Polynuclear Aromatic Hydrocarbons (PNAs): PNAs, such as naphthalene, and biphen-
yls, are a group of highly reactive organic compounds that are a common component of
creosotes, which can be carcinogenic.
Potentially Responsible Parties (PRPs): Parties, including owners, who may have
contributed to the contamination at a Superfund site and may be liable for costs of
response actions. Parties are considered PRPs until they admit liability or a court makes
a determination of liability. This means that PRPs may sign a consent decree or admin-
istrative order on consent [see Administrative Order on Consent] to participate in site
cleanup activity without admitting liability.
Radionuclides: Elements, including radium, and uranium-235 and -238, which break
down and produce radioactive substances due to their unstable atomic structure. Some
are man-made and others are naturally occurring in the environment. Radon, which is
the gaseous form of radium, decays to form alpha particle radiation, which can be easily
blocked by skin. However, it can be inhaled, which allows alpha particles to affect
unprotected tissues directly and thus cause cancer. Uranium, when split during fission
in a nuclear reactor, forms more radionuclides which, when ingested, can also cause
cancer. Radiation also occurs naturally through the breakdown of granite stones.
Runoff: The discharge of water over land into surface water. It can carry pollutants
from the air and land into receiving waters.
Sediment: The layer of soil, sand and minerals at the bottom of surface waters, such as
streams, lakes, and rivers that absorb contaminants.
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Seeps: Specific points where releases of liquid (usually leachate) form from waste
disposal areas, particularly along the lower edges of landfills.
Sludge: Semi-solid residues from industrial or water treatment processes that may be
contaminated with hazardous materials.
Stabilization: The process of changing an active substance into inert, harmless mate-
rial, or physical activities at a site that act to limit the further spread of contamination
without actual reduction of toxicity.
Sumps: A pit or tank that catches liquid runoff for drainage or disposal.
Surge Tanks: A holding structure used to absorb irregularities in flow of liquids, in-
cluding liquid waste materials.
Trichloroethylene (TCE): A stable, colorless liquid with a low boiling point. TCE has
many industrial applications, including use as a solvent and as a metal degreasing
agent. TCE may be toxic to people when inhaled, ingested, or through skin contact and
can damage vital organs, especially the liver [see also Volatile Organic Compounds].
Upgradient: An upward slope; demarks areas that are higher than contaminated areas
and, therefore, are not prone to contamination by the movement of polluted groundwa-
Upslope: Upstream; often used relative to groundwater [see Upgradient].
Volatile Organic Compounds (VOCs): VOCs are made as secondary petrochemicals
They include light alcohols, acetone, trichloroethylene, perchloroethylene, dichloroeth-
ylene, benzene, vinyl chloride, toluene, and methylene chloride. These potentially toxic
chemicals are used as solvents, degreasers, paints, thinners, and fuels. Because of their
volatile nature, they readily evaporate into the air, increasing the potential exposure to
humans. Due to their low water solubility, environmental persistence, and widespread
industrial use, they are commonly found in soil and groundwater.
Watershed: The land area that drains into a stream or other water body.
Wetland: An area that is regularly saturated by surface or groundwater and, under
normal circumstances, capable of supporting vegetation typically adapted for life in
saturated soil conditions. Wetlands are critical to sustaining many species of fish and
wildlife. Wetlands generally include swamps, marshes, and bogs. Wetlands may be
either coastal or inland. Coastal wetlands have salt or brackish (a mixture of salt and
fresh) water, and most have tides, while inland wetlands are non-tidal and freshwater.
Coastal wetlands are an integral component of estuaries.
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