&EPA
United States
Environmental Protection
Agency
Solid Waste And
Emergency Response
(5102G)
SUPERFUND:
EPA/540/R-93/047
December 1992
PB93-963249
                Progress at
                National
                Priority
                List Sites
        WYOMING
      1992 UPDATE
Printed on Recycled Paper

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                                        Publication #9200.5-7496
                                             December 1992
     NATIONAL PRIORITIES LIST SITES:
                   Wyoming
                                      ?'i3S3 Boa'd' 12* Fleet
                                  77 West Jf K|00n654-3590
                                  Chicago, iL ou
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
       Office of Emergency & Remedial Response
            Office of Program Management
               Washington, DC 20460

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If you wish to purchase copies of any additional State volumes, contact:
                  National Technical Information Service (NTIS)
                         U.S. Department of Commerce
                            5285 Port Royal Road
                            Springfield, VA 22161
                                (703) 486-4650
The complete set of the 49 State reports may be ordered as PB93-963250.

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        TABLE OF CONTENTS
INTRODUCTION
   A Brief Overview of Superfund	v
   Streamlining Superfund: The Superfund Accelerated Cleanup Model	ix
   How Superfund Works	x


THE VOLUME
   How to Use the State Book	xi
A SUMMARY OF THE STATE PROGRAM
.XV
THE NPL REPORT
    Progress to Date	xix
THE NPL FACT SHEETS                     i
THE GLOSSARY
    Terms used in the NPL Book	G-l

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                     INTRODUCTION
           A BRIEF OVERVIEW OF SUPERFUND
     During the second half of the Twentieth
     Century, the environmental conse-
quences of more than 100 years of industrial-
ization in the United States became increas-
ingly clear. Authors such as Rachel Carson
wrote passionately about the often-hidden en-
vironmental effects of our modern society's
widespread use of chemicals and other haz-
ardous materials. Their audience was small at
first, but gradually their message spread.
Growing concern turned to action, as people
learned more about the environment and be-
gan to act on their knowledge

The 1970s  saw environmental issues burst
onto the national scene and take hold in the
national consciousness. The first Earth Day
was observed in 1970, the year that the U.S.
Environmental Protection Agency (EPA) was
founded. By the end of the 1970s, Love Canal
in New York and the Valley of the Drums in
Kentucky had entered the popular lexicon as
synonyms for pollution and environmental
degradation.
Superfund Is Established

The industrialization that gave Americans the
world's highest standard of living also created
problems that only a national program could
address. By 1980, the U.S. Congress had
passed numerous environmental laws, imple-
mented by the EPA, but many  serious hazard-
ous waste problems were slipping through the
cracks.

Responding to growing concern about public
health and environmental threats from uncon-
trolled releases of hazardous materials, the
U.S. Congress passed the Comprehensive En-
vironmental Response, Compensation, and
Liability Act (CERCLA). Popularly known as
Superfund, CERCLA had one  seemingly
simple job-—to uncover and clean up hazard-
ous materials  spills and contaminated sites.
A Big Job

Few in Congress, the EPA, the environmen-
tal community, or the general public knew in
1980 just how big the nation's hazardous ma-
terials problem is. Almost everyone thought
that Superfund would be a short-lived pro-
gram requiring relatively few resources to
clean up at most a few hundred sites. They
were quite mistaken.

As the EPA set to work finding sites and
gauging their potential to harm people and
the environment, the number of sites grew.
Each discovery seemed to lead to another,
and today almost 36,000 hazardous waste
sites have been investigated as potential haz-
ardous waste  sites. They are catalogued in
the EPA's computerized database, CERCLIS
(for the Comprehensive Environmental Re-

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INTRODUCTION
sponse, Compensation, and Liability Informa-
tion System).

The damage to public health and the environ-
ment that each site in CERCLIS might cause
is evaluated; many sites have been referred to
State and local governments for cleanup. The
EPA lists the nation's most serious hazardous
waste sites on the National Priorities List, or
NPL. (These Superfund sites are eligible for
federally-funded cleanup, but whenever pos-
sible the EPA makes polluters pay for the
contamination they helped create.) The NPL
now numbers 1,275 sites, with 50 to 100
added each year. By the end of the century,
the NPL may reach as many as 2,100 sites.

Superfund faces some of the most complex
pollution problems ever encountered by an
environmental program. Improperly stored or
disposed chemicals and the soil they contami-
nate are one concern. More difficult to correct
are the wetlands and bays, and the groundwa-
ter, lakes, and rivers often used for drinking
water that are contaminated by chemicals
spreading through the soil or mixing with
storm water runoff. Toxic vapors contaminate
the air at some sites, threatening the health of
people living and working near by.

Superfund aims to control immediate public
health and environmental threats by tackling
the worst problems at the worst sites first.
Wherever possible, Superfund officials use
innovative treatment techniques—many de-
veloped or refined by the EPA—to correct
hazardous materials problems once and for
all. Many of the treatment techniques they use
did not exist when the program was created.

The EPA Administrator had challenged Su-
perfund to complete construction necessary
for cleanup work at 130 NPL sites by the end
of the 1992 federal fiscal year. By September
30, 1992, the end of fiscal year 1992, con-
struction had been completed at a total of 149
NPL sites. Superfund is well on its way of
meeting the Administrator's goal of complet-
ing construction at 200 NPL sites by the end
of fiscal year 1993, and 650 sites by the end
of fiscal year 2000.
Quick Cleanup at
Non-NPL Sites

Long-standing hazardous waste sites are not
Superfund's only concern. The EPA also re-
sponds to hazardous spills and other emergen-
cies, hauling away chemicals for proper treat-
ment or disposal. Superfund teams perform or
supervise responses at rail and motor vehicle
accidents, fires, and other emergencies in-
volving hazardous substances. They also
evacuate people living and working near by,
if necessary, and provide clean drinking water
to people whose own water is contaminated.
Removal crews also post warning signs and
take other precautions to keep people and ani-
mals away from hazardous substances.
                                             Superfund employee prepares equipment far groundwater
                                             treatment.
                                           VI

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                                                              INTRODUCTION
Quick Cleanups, or Removals, are not limited
to emergencies. When cleanup crews at con-
taminated sites find hazardous substances that
immediately threaten people or the environ-
ment, they act right away to reduce the threat
or to remove the chemicals outright.  As the
EPA implements the Superfund Accelerated
Cleanup Model (SACM), more and more sites
will undergo quick cleanups, and many of
these will be cleaned up completely without
ever being included on the NPL. (See
"Streamlining Superfund: The Superfund Ac-
celerated Cleanup  Model.")

Some of Superfund's most significant gains in
public health and environmental protection
have been won by  the removal program. As of
March 31, 1992, the Emergency Response
Superfund employee removing drums from a Superfund site.

Program had logged more than 2,300 removal
completions since Superfund was established.
The Public's Role

Superfund is unique among federal programs
in its commitment to citizen participation. Al-
though the EPA is responsible for determin-
ing how dangerous a site is and how best to
clean it up, the Agency relies on citizen input
as it makes these decisions.

Community residents are often invaluable
sources of information about a hazardous
waste site, its current and previous owners,
and the activities that took place there. Such
information can be crucial to experts evaluat-
ing a site and its potential dangers.

Residents also comment on EPA cleanup
plans by stating their concerns and prefer-
ences at public meetings and other forums and
in formal, written comments to Agency pro-
posals. The EPA takes these comments and
concerns seriously, and has modified many
proposals in response to local concerns. For,
ultimately, it is the community and its citizens
that will live with the results of the EPA's de-
cisions and actions; it is only fair that citizens
participate in the process.
A Commitment to
Communication

The Superfund program is very serious about
public outreach and communication. Com-
munity relations coordinators are assigned to
each NPL site to help the public understand
the potential hazards present, as well as the
cleanup alternatives. Local information re-
positories, such as libraries or other public
buildings, have been established near each
NPL site to ensure that the public has an op-
portunity to review all relevant information
and the proposed cleanup plans.

The individual State volumes contain sum-
mary fact sheets on NPL sites in each State
and territory. Together, the fact sheets provide
a concise report on site conditions and the
progress made toward site cleanups as of
March 1992. The EPA revises these volumes
periodically to provide an up-to-date record of
program activities. A glossary of key terms
relating  to hazardous waste management and
Superfund site cleanup is provided at the back
of this book.
                                          vii

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INTRODUCTION
Superfund is, of course, a public program, and
as such it belongs to everyone of us. This vol-
ume, along with other State volumes, com-
prises the EPA's report on Superfund
progress to the program's owners for the year
1992.
                                        VIII

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                                                          INTRODUCTION
  STREAMLINING SUPERFUND: THE SUPERFUND
             ACCELERATED CLEANUP MODEL
      Historically, critics and supporters alike
      have measured Superfund's progress
by the number of hazardous waste sites de-
leted from the NPL. Although easy enough to
tally, this approach is too narrow. It misses
the major gains Superfund makes by reducing
major risks at the nation's worst hazardous
sites long before all clean-up work is done
and the site deleted. It also ignores the Re-
moval Program's contributions to meeting
Superfund's twin mandates of maximizing
public health and environmental protection.

Renewing Superfund's commitment to rapid
protection from hazardous materials, the EPA
is streamlining the program. The Superfund
Accelerated Cleanup Model, or SACM, will
take Early Actions, such as removing hazard-
ous wastes or contaminated  materials, while
experts study the site. SACM also will com-
bine similar site studies to reduce the time re-
quired to evaluate a site and its threats to
people and the environment. This way, imme-
diate public health and environmental threats
will be addressed while long-term cleanups
are being planned.

Emergencies such as train derailments and
motor vehicle accidents will continue to be
handled expeditiously. Teams of highly
trained technicians will swing into action
right away, coordinating the cleanup and re-
moval of hazardous substances to ensure pub-
lic safety as quickly as possible.

Breaking With Tradition

The traditional Superfund process begins with
a lengthy phase of study and site assessment,
but SACM will save time by combining sepa-
rate, yet similar, activities. Each EPA Region
will form a Decision Team of site managers,
risk assessors, community relations coordina-
tors, lawyers, and other experts to monitor the
studies and quickly determine whether a site
requires Early Action (taking less than five
years), Long-term Action, or both.

While the site studies continue, the Decision
Team will begin the short-term work required
to correct immediate public health or environ-
mental threats from the site. Besides remov-
ing hazardous materials, Early Actions in-
clude taking precautions to keep contaminants
from moving off the site and restricting access
to the site. Early Actions could eliminate most
human risk from these sites, and Superfund
will further focus its public participation and
public information activities on site assess-
ment and Early Action.

Long-Term Solutions

While Early Actions can correct many hazard-
ous waste problems—and provide the bulk of
public health and environmental protection—
some contamination will take longer to cor-
rect. Cleanups of mining sites, wetlands, estu-
aries, and projects involving incineration of
contaminants or restoration of groundwater
can take far longer than the three to five years
envisioned for Early Actions. Under SACM,
these sites will be handled much as they are
now.

Also under SACM, the EPA will continue its
pursuit of potentially responsible parties who
may have caused or contributed to site con-
tamination. Expedited  enforcement and
procedures for negotiating potentially respon-
sible party settlements will secure their par-
ticipation. Superfund personnel will continue
to oversee clean-up work performed by poten-
tially responsible parties.
                                        IX

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INTRODUCTION
                    HOW SUPERFUND WORKS
     Each Superfund site presents a different
     set of complex problems. The same haz-
ardous materials and chemicals often con-
taminate many sites, but the details of each
site are different. Almost always, soil is con-
taminated with one or more chemicals. Their
vapors may taint the air over and around the
site. Contaminants may travel through the soil
and reach underground aquifers which may be
used for drinking water, or they may spread
over the site to contaminate streams, ponds,
and wetlands. The contaminating chemicals
may interact with each other, presenting even
more complicated cleanup problems.

Superfund's cleanup process is arduous and
exacting. It requires the best efforts of hun-
dreds of experts in science and engineering,
public health, administration and manage-
ment, law, and many other fields.

The average NPL site takes from seven  to ten
years to  work its way through the system,
from discovery to the start of long-term
cleanup. Actual cleanup work can take years,
decades  if contaminated groundwater must
be treated. Of course, imminent threats to
public health or the environment are cor-
rected right away.

The diagram to the right presents a simplified
view of the cleanup process. The major steps
in the Superfund process are:

  • Site discovery and investigation to iden-
   tify contaminants and determine whether
   emergency action is required;

  • Emergency site work such as removing
   contaminants for proper treatment or dis-
   posal, and securing the site to keep people
   and animals away, if warranted by condi-
   tions  at the site;

  • Site evaluation to determine how people
   living and working nearby, and the envi-
   ronment, may be exposed to site contami-
   nants;
 • Detailed studies to determine whether con-
  ditions are serious enough to add the site to
  the National Priorities List of sites eligible
  for federally funded cleanup under Super-
  fund;

 • Selection, design, and implementation of a
  cleanup plan, after a thorough review of
  the most effective cleanup options, given
  site conditions, contaminants present, and
  their potential threat to public health or the
  environment.

 • Follow-up to ensure that the cleanup work
  done at the site continues to be effective
  over the long term.
   The Superfund Process
From the earliest stages, EPA investigators
work hard to identify those responsible for the
contamination. As their responsibility is es-
tablished, the EPA negotiates with these "re-
sponsible parties" to pay for cleaning up the
problem they helped create. This "enforce-
ment first" policy saves Superfund Trust Fund
monies for use in cleanups where the respon-
sible parties cannot be identified, or where
they are unable to fund cleanup work.

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                          THE VOLUME
                    How to  Use the  State  Book
  •  he site fact sheets presented in this book
 JL are comprehensive summaries that cover
a broad range of information. The fact sheets
describe hazardous waste sites on the NPL and
their locations, as well as the conditions
leading to their listing ("Site Description").
The summaries list the types of contaminants
that have been discovered and related threats
to public and ecological health ("Threats and
Contaminants"). "Cleanup Approach" pres-
ents an overview of the cleanup activities
completed,  underway, or planned. The fact
sheets conclude with a brief synopsis of how
much progress has been made in protecting
public health and the environment. The
summaries also pinpoint other actions,  such as
legal efforts to involve polluters responsible
for site contamination and community con-
cerns.

The fact sheets are arranged in alphabetical
order by site name.  Because site cleanup is a
dynamic and gradual process, all site informa-
tion is accurate as of the date shown on the
bottom of each page.  Progress always is being
made at NPL sites, and the EPA periodically
will update the site fact sheets to reflect recent
actions and will publish updated State vol-
umes. The following  two pages show a ge-
neric fact sheet and briefly describe the infor-
mation under each section.
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.  The EPA is committed to
involving the public in the decision making
process associated with hazardous waste
cleanup. The Agency solicits input from area
residents in communities affected by Super-
fund sites. Citizens are likely to be affected
not only by hazardous site conditions, but also
by the remedies that combat them. Site clean-
ups take many forms and can affect communi-
ties in different ways. Local traffic may be
rerouted, residents may be relocated, tempo-
rary water supplies may be necessary.
Definitive information on a site can help
citizens sift through alternatives and make
decisions.  To make good choices, you must
know what the threats are and how the EPA
intends to clean up the site. You must under-
stand the cleanup alternatives being proposed
for site cleanup and how residents may be
affected by each one.  You also need to have
some idea  of how your community intends to
use the site in the future, and you need to know
what the community can realistically expect
once the cleanup is complete.

The EPA wants to develop cleanup methods
that meet community needs, but the Agency
only can take local concerns into account if it
understands what they are.  Information must
travel both ways in order for cleanups to be
effective and satisfactory.  Please take this
opportunity to learn more, become involved,
and assure that hazardous waste cleanup at
"your" site considers your community's
concerns.
                                           XI

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THE VOLUME
   NPL LISTING HISTORY

 Provides the dates when the
 site was Proposed, made Final,
 and Deleted from the NPL.
   SITE RESPONSIBILITY

  Identifies the Federal, State,
  and/or potentially responsible
  parties taking responsibility
  for cleanup actions at the site.
      ENVIRONMENTAL
         PROGRESS

  Summarizes the actions to
  reduce the threats to nearby
  residents and the surrounding
  environment and the progress
  towards cleaning up the site.
                               SITE NAME
                                     EPA REGION XX
                                        COUNTY NAME
                                          LOCATION
STATE
EPA ID# ABCOOOOOOO
                               Site Description
Site Responsibility:
                                        NPL Listing History
                                         Proposed XX/XX/XX
                                          Final. XX/XX/XX
Threats and Contaminants
                               Cleanup Approach
                               Response Action Status
XXX XXXXXX XXXXXXXXXXXX XX XXXXXXX XXX XXXXXX XX XXXXXX XXXXXXXX XXX XXXXXXXXX
Environmental Progress
                               Site Repository

                                                 xxxxxx xxx:
                                                             :xx:xx xxxxxx.
                                                       SITE REPOSITORY

                                       Lists the location of the primary site repository. The site
                                       repository may include community relations plans, public
                                       meeting announcements and minutes, fact sheets, press
                                       releases, and other site-related documents.
                                              XII

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                                                   THE VOLUME
                         SITE DESCRIPTION

This section describes the location and history of the site.  It includes descrip-
tions of the most recent activities and past actions at the site that have con-
tributed to the contamination.  Population estimates, land usages, and nearby
resources give readers background on the local setting surrounding the site.
                   THREATS AND CONTAMINANTS

The major chemical categories of site contamination are noted, as well as
which environmental resources are affected. Icons representing each of the
affected resources (may include air, groundwater, surface water, soil, and
contamination to environmentally sensitive areas)  are included in  the margins
of this section. Potential threats to residents and the surrounding environ-
ments arising from the site contamination also are  described.
                        CLEANUP APPROACH

This section contains a brief overview of how the site is being cleaned up.
                     RESPONSE ACTION STATUS

Specific actions that have been accomplished or will be undertaken to clean
up the site are described here. Cleanup activities at NPL sites are divided
into separate phases, depending on the complexity and required actions at the
site. Two major types of cleanup activities often are described: initial,
immediate, or emergency actions to quickly remove or reduce imminent
threats to the community and surrounding areas; and long-term remedial
phases directed at final cleanup at the site. Each stage of the cleanup strategy
is presented in this section of the summary. Icons representing the stage of
the cleanup process (initial actions, site investigations, EPA selection of the
cleanup remedy, engineering design phase, cleanup activities underway, and
completed cleanup) are located in the margin next to each activity descrip-
tion.
                             SITE FACTS

Additional information on activities and events at the site are included in this
section. Often details on legal or administrative actions taken by the EPA to
achieve site cleanup or other facts pertaining to community involvement with
the site cleanup process are reported here.

                          xiii

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THE VOLUME
The "icons," or symbols, accompanying the text allow the reader to see at a glance which envi-
ronmental resources are affected and the status of cleanup activities at the site.
   Icons in the Threats
     and  Contaminants
             Section
       Contaminated Groundwater resources
       in the vicinity or underlying the site.
       (Groundwater is often used as a drink-
       ing water source.)

       Contaminated Surface Water and
       Sediments on or near the site.  (These
       include lakes, ponds, streams, and
       rivers.)

       Contaminated Air in the vicinity of
       the site.  (Air pollution usually is
       periodic and involves contaminated
       dust particles or hazardous gas emis-
       sions.)

       Contaminated Soil and Sludges on or
       near the site. (This contamination
       category may include bulk or other
       surface hazardous wastes found on the
       site.)

       Threatened or contaminated Environ-
       mentally Sensitive Areas in the vicinity
       of the site.  (Examples include wet-
       lands and coastal areas or critical
       habitats.)
Icons in the Response
Action Status Section
       Initial, Immediate, or Emergency
       Actions have been taken or are
       underway to eliminate immediate
       threats at the site.

      Site Studies at the site to determine
      the nature and extent of contamination
      are planned or underway.

     Remedy Selected indicates that site
     investigations have been concluded,
     and the EPA has selected a final
     cleanup remedy for the site or part of
     the site.

       Remedy Design means that engineers
       are preparing specifications and
       drawings for the selected cleanup
       technologies.

      Cleanup Ongoing indicates that the
      selected cleanup remedies for the
      contaminated site, or part of the site,
      currently are underway.

       Cleanup Complete shows that all
       cleanup goals have been achieved for
       the contaminated site or part of the
       site.
                                        XIV

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A SUMMARY OF THE STATE PROGRAM
             xv

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                                Superftmd Activities


                                in  Wyoming


                                     The State of Wyoming is located within EPA Region
                                8, which includes the six northern central States extending
                                from the central plains to the Rocky Mountains. The State
                                covers 97,809 square miles. According to the 1990 Census,
                                Wyoming experienced more than a 3 percent decrease in
              *-*•"               population between 1980 and 1990, and has the smallest U.S.
population with approximately 453,600 residents.
      The Wyoming Environmental Quality Act (EQA) of 1987 provides the State the authority to
clean up Superfund sites. The EQA requires containment and notification of releases and grants the
State the authority to gain site access, issue orders, and seek criminal and civil penalties through the
State's Attorney General.  In practice, the State notifies polluters of their liability for cleanup activi-
ties and ascertains their ability and willingness to perform cleanups. If the polluters are unwilling or
unable to clean up the site, the State requests funds from a contingency account of the governor, a
trust account maintained by the Department of Environmental Quality, or the Federal Superfund
program to conduct cleanup activities itself.  No funding was originally appropriated for cleanup
activities conducted by the State; however, in 1989 a new provision under the Statute earmarked
funds for emergency actions performed with State approval. Interested citizens may bring civil suits
against polluters to compel compliance to the extent that such an action could have been brought in
Federal district court Also, the public is able to participate in the cleanup process through access to
information collected under the EQA. To promote community involvement, the State created two
citizen commissions to comment on site activities at the Mystery Bridge and F.E. Warren Air Force
Base NPL sites. Currently, three sites in the  State of Wyoming have been listed as final on the NPL.
No new sites have been proposed for listing in 1992.
                   The Department of Environmental Quality
            implements the Superfund Program in the State of Wyoming
Activities responsible for hazardous
waste contamination in the State of
Wyoming include:
Petroleum and
Refining
Operations
                                 Federal
                                Facilities
                          Railroad Yards
Facts about the three NPL sites
in Wyoming:
        Immediate Actions (such as removing
        hazardous substances or restricting
        site access) were performed at two
        sites.


        No sites endanger sensitive environ-
        ments.


        Three sites are located near residential
        areas.
                                       xvii
                                March 1992

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WYOMING
Most Sites Have Multiple Contaminants and
Contaminated Media:
Media Contaminated at Sites
Air

Surface
Water

Sediments
Soil


Ground-
water
       0 10  20 30 40  50 60  70 80 90  100

             Percentage of Sites
   Contaminants Found at Sites
Percentage of Sites
VOCs
Petrochemicals/Explosives
Creosotes
Acids
67%
67%
33%
33%
The Potentially Responsible
Party Pays...
In the State of Wyoming, potentially responsible
parties are paying for or conducting cleanup
activities at two sites.
For Further Information on NPL Sites and Hazardous
Waste Programs in the State of Wyoming Please Contact:
« EPA Region 8 Puttie Affairs
Branch
tr National Response Center
* The Department of Environmental
Quality: Water Quaftty Division
ff EPA Region 8 Hazardous Waste
Management Division
* EPA Superfund Hotline
For information concerning
community involvement
To report a hazardous
waste emergency
For information about the
State's responsfljilfty in the
Superfund Program
For Information about the
Regional Superfund Program
For information about the
Federal Superfund Program
(303)294-1120
(800} 424-8802
(307) 777-7781
(303} 294-7630
(800) 424-9068

March 1992
xviii

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                    THE NPL  REPORT
                         PROGRESS TO DATE
     The following Progress Report lists all
     sites currently on, or deleted from, the
NPL and briefly summarizes the status of ac-
tivities 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 (^>) indicating the
current stage of cleanup.

Large and complex sites often are 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 differ-
ent 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 ac-
complishments.

   £> An arrow in the "Initial Response" cate-
     gory indicates that an emergency
     cleanup, immediate action, or initial ac-
     tion has been completed or currently is
     underway. Emergency or initial actions
     are taken as an interim measure to pro-
     vide immediate relief from exposure to
     hazardous site conditions or to stabilize
     a site to prevent further contamination.

   ^> A final arrow in the "Site Studies" cat-
     egory indicates that an investigation to
     determine the nature and extent of the
     contamination at the site currently is on-
     going or planned.

   O A final arrow in the "Remedy Selection"
     category means that the EPA has se-
     lected 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" rem-
     edy has been selected. In these cases,
     the arrows are discontinued at the
     "Remedy Selection" step and resume in
     the "Construction Complete" category.

  O A final arrow at the "Remedial Design"
     stage indicates that engineers currently
     are designing the technical specifica-
     tions for the selected cleanup remedies
     and technologies.

  O A final arrow in the "Cleanup Ongoing"
     column means that final cleanup actions
     have been started at the site and cur-
     rently are underway.

  ^ A final arrow in the "Construction Com-
     plete" category is used only when all
     phases of the site cleanup plan have
     been performed, and the EPA has deter-
     mined that no additional construction
     actions are required at the site.  Some
     sites in this category currently may be
     undergoing long-term operation and
     maintenance or monitoring to ensure
     that the cleanup actions continue to pro-
     tect human health and the environment.

  / A check in the "Deleted" category indi-
     cates that the site cleanup has met all
     human health and environmental goals
     and that the EPA has deleted the site
     from the NPL.

Further information on the activities and
progress at each site is given in the site "Fact
Sheets" published in this volume.
                                         XIX

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                                        XX

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BAXTER/UNI
PACIFIC
TIE TREATI
WYOMING
EPAID#WYD061112470
Site Description
                                             EPA REGION 8
                                                Albany County
                                           3/4 miles southwest of Laramfe
The Union Pacific Railroad, or its contractor, treated railroad ties at the Baxter/Union
Pacific Tie Treating site between 1886 and 1983, using various chemicals including zinc
chloride, a mixture of creosote oil and an asphalt-based oil, and pentachlorophenol (PCP).
During the operation's  first 70 years, workers disposed of process wastes in the Laramie
waste collection ponds.  Contamination outside these ponds was discovered in 1981 during
groundwater monitoring required by the EPA. Approximately 140 acres of the property's 700
acres currently are polluted with oils and wood treating chemicals. The railroad voluntarily
ceased operations at the site in 1983. The City of Laramie has a population of 24,000. The
public water supply for  Laramie is not connected to the site; the city uses a reservoir fed by
the Laramie River several miles upriver. Contaminated water beneath the site is not used for
drinking, and domestic  private wells near the site were sampled and found clean.
Site Responsibility:  This site is being addressed through
                    Federal and potentially responsible
                    parties' actions.
                                             NPL USTINQ HISTORY
                                             Proposed Date: 12/30/82
                                               Final Date: 09/08/83
Threats and Contaminants
ZGJ
Groundwater, soil, and sediments contained numerous polycyclic aromatic
hydrocarbons (PAHs) including PCP. PCP levels were shown to be higher
downgradient, indicating movement of contaminants from the site. The public
drinking supply is protected, as it is drawn from above the contamination area;
however, direct contact with site contaminants is a possible health threat.
                                                                     March 1992

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Cleanup Approach
This site is being addressed in two long-term remedial phases focusing on source control and
cleanup of the contaminated groundwater and soil.
Response Action Status
          Source Control: The EPA selected an interim remedy to control the source of
          contamination and to address groundwater cleanup in 1986. The remedy features
          an isolation system designed to keep contaminated groundwater and soil from
moving off site while more permanent remedies are planned. This remedy includes: realigning
the Laramie River Channel 150 feet farther west from the site to reduce the chance of
contamination; constructing a slurry wall through the soil and bedrock around contaminated
areas; draining and pumping groundwater against its natural flow to keep it from seeping off
site and through the slurry wall; treating withdrawn groundwater with activated carbon to
decontaminate it; discharging this cleaned water into the Laramie River, under State and
Federal permits; and monitoring the groundwater to track the effectiveness of the system. All
cleanup activities have been  completed. Operation and maintenance, as well as monitoring of
the remedies are taking place to ensure that cleanup actions continue to be effective.

          Groundwater and Soil: In 1990, Union Pacific began treatability studies, under
          EPA monitoring, to  determine if bioremediation of contaminated soil and
          groundwater would be an effective remedy. Other alternatives also are being
evaluated. These studies are scheduled to be completed in late 1992.
Environmental Progress
The cleanup actions to contain the source of contamination have been completed at the
Baxter/Union Pacific Tie Treating site. Monitoring to ensure the interim remedies'
effectiveness is continuing while groundwater and soil treatability studies are underway.
Site Repository

Albany County Public Library, 310 South Eighth Street, Laramie, WY 82070
March 1992                                2           BAXTER/UNION PACIFIC TIE TREATING

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F.E.  WARREN
FORCE  BASE
WYOMING
EPA ID# WY5571924179
Site Description
                                                    REGION 8
                                                  Laramie County
                                                    Cheyenne
The 5,866-acre F.E. Warren Air Force Base site initially began as a U.S. Army cavalry
outpost in 1867 and has since served a number of military functions. In 1947, control of the
facility was transferred to the U.S. Air Force, and it became a Strategic Air Command base
in 1958. Waste generation at the facility has consisted primarily of spent solvents from
equipment cleaning and various maintenance operations. The Air Force also maintained an
acid well used for spent battery acid disposal. While five landfills are located at the facility
and hold various wastes, only one landfill is presently in operation. Two fire protection areas
involved extensive use of various fuels and combustible materials for fire training exercises.
Initially, 25 areas were identified where hazardous materials might have been used, stored,
treated, or disposed. Agricultural lands and industrial and residential developments surround
the base.  The City of Cheyenne borders the base on the east.  Approximately 2,400 people
draw drinking water from private deep aquifer wells. These wells lie within a 3 mile radius of
hazardous substances on the base.
Site Responsibility: This site is being addressed through
                    Federal actions.
                                               NPL LISTING HISTORY
                                               Proposed Date: 07/14/89
                                                 Final Date: 02/21/90
Threats and Contaminants
ZGJ
Contamination from trichloroethylene (TCE), gasoline, oils, hydraulic fluid,
ethylene glycol, and battery acid was found in shallow groundwater zones and soils.
TCE was found in surface water samples at various locations. Contaminated
groundwater, discharging to surface waters (Crow and Diamond Creeks), is
believed to be the TCE contamination source. Direct contact with contaminated
groundwater, surface water, and soil may adversely affect human health.
                                                                       March 1992

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Cleanup Approach
This site is being addressed in two stages: initial actions and a long-term remedial phase
focusing on cleanup of the entire site.
Response Action Status
           Initial Actions: In 1986, the Air Force removed an acid disposal well system and
           an unknown amount of contaminated soil. In 1989, the Air Force removed a
           building drain sump,  3,000 gallons of contaminated liquid, 300 gallons of
contaminated sludge, and 300,000 pounds of contaminated soil from an area known as Spill
Site 7.

           Entire Site: In 1991, a Federal Facility Agreement divided the entire site into
           seven cleanup areas. These consist of shallow and deep groundwater zones (two
           separate stages), the acid dry well area, the landfills, the fire training areas, the
base firing range, and a munitions  detonation area. A draft report from a site investigation
conducted under the Installation Restoration Program (IRP) was completed and reviewed by
the EPA and the State. Further investigations are needed to determine contamination in
deeper groundwater zones. Also, the extent of potential or suspected surface sources needs
to be further identified. The Air Force currently is preparing plans to conduct further site
investigations at surface sources and to determine deeper groundwater contamination.  Work
activities are to begin in the acid dry well area in 1992.

Site Facts:  A Federal Facility  Agreement was signed September 26, 1991, defining EPA
and State involvement in future  site investigations and cleanup actions. The Agreement
divides the  site into seven cleanup  areas. F.E. Warren Air Force Base is participating in the
IRP, a specially funded program developed in 1978 by the Department  of Defense (DOD) to
identify, investigate, and control the migration of hazardous contaminants at military and
other DOD facilities.
Environmental  Progress
The initial actions to remove contaminated soil, sludge, and liquids have greatly reduced the
potential for exposure to hazardous substances at the F.E. Warren Air Force Base site while
further studies are taking place and cleanup activities are being planned.
Site Repository

Laramie County Public Library, 2800 Central Avenue, Cheyenne, WY 82001
March 1992                                 4                 F.E. WARREN AIR FORCE BASE

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 MYSTERY  B
 ROAD/HIGH
 WYOMING
 EPA ID# WYD981546005
Site Description
EPA REGION 8
   Natrona County
  mile east of Evansville

    Other Names:
     Brookhurst
The 450-acre Mystery Bridge Road/Highway 20 site is located adjacent to an oil refinery and
other industries in the Brookhurst and Mystery Bridge Subdivisions. One area of the site, the
KN Energy facility, serves as a natural gas processing operation. There was an unlined waste
pond on this area that was used from 1965 until 1984. Another area of the site operated as
an oil field service and includes a former toluene storage area, a truck wash drain system, and
an abandoned sump. Studies started in 1986 in response to citizen complaints identified the
presence of volatile organic compounds (VOCs) in area wells and drinking water. The
Brookhurst Subdivision was developed during the mid-1970s and consists of about 100 homes,
90 of which are affected by chlorinated hydrocarbon contamination of drinking water wells.
Domestic wells in the area tap into shallow groundwater. In 1988, a contaminated
groundwater plume moving from the Little America Refining Co. (LARCO), an area
adjacent to the Brookhurst property, was also identified.
Site Responsibility:  This site is being addressed through
                    Federal and potentially responsible
                    parties' actions.
 NPL USTING HISTORY
 Proposed Date: 06/24/88
   Final Date: 08/30/90
Threats and Contaminants
         Groundwater and soil are contaminated with VOCs, hydrocarbons, and other
         hazardous substances. Drinking of or direct contact with contaminated
         groundwater are the greatest health threats to Brookhurst residents.
Cleanup Approach
This site is being addressed in three stages: immediate actions and two long-term remedial
phases focusing on cleanup of the groundwater and remaining subsurface contamination.
                                                                      March 1992

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Response Action Status
           Immediate Actions: In 1987, the EPA provided bottled water to 45 residences
           as an interim measure until the water distribution system was installed later in the
           year. Hookups to the drinking water system between Evansville and Brookhurst
were completed in 1988. A sedimentation pond and intake structure modifications were
constructed at the Evansville water treatment plant. In 1988, KN Energy removed 35 drums
of liquid and sludge from the flare pit area and sent the drums off site to a disposal facility.
KN Energy also installed a pump and treat system and soil vapor extraction system to
mitigate the release of contaminants into the groundwater. In 1988,  The Dow Chemical
Company and Dowell-Schlumberger removed 420 cubic yards of contaminated soil from the
facility and installed a soil vapor extraction system to remove remaining contaminants in the
soil.

           Groundwater: In 1990, Dow,  Dowell-Schlumberger, and KN Energy completed
           an investigation into the nature and extent of contamination at the site. Work
           performed during the investigation, including the installation of monitoring wells,
soil vapor analysis, surface and sediment sampling, and collection of water samples from
monitoring wells, was completed in 1989. Three containment plumes were identified in the
groundwater. In 1990, the EPA selected a  remedy to cleanup the groundwater, which
includes: pumping of the first plume, which contains benzene, ethylbenzene, xylenes and
toluene and treatment using air stripping; and limited pumping of the second plume, which
contains VOCs, and treatment using air stripping and reinjection of  clean water into the
aquifer. The third plume is being addressed under the Resource Conservation and Recovery
Act (RCRA). Design of the selected remedy began in 1991.

           Subsurface Contamination: An investigation to address any remaining
           subsurface contamination and potential impacts on the effectiveness of the
           groundwater cleanup is currently underway. KN Energy will perform batch leach
tests for soil contamination to determine when to discontinue the immediate actions at KN's
facility. They also  will install a system to accelerate removal of any remaining soil and
groundwater contamination beneath its facility. These activities are planned for completion  in
the fall of 1993. At that time, EPA will determine whether these activities have adequately
removed the sources of groundwater contamination with regard to KN Energy and evaluate
whether additional cleanup activities are needed. Dow Chemical Company and Dowell-
Schlumberger are currently developing a work plan to investigate additional groundwater
contamination.
Site Facts: In 1988, the EPA issued Consent Orders to three potentially responsible parties,
KN Energy, Inc., Dow Chemical Company, and Dowell Schlumberger, Inc., ordering them to
clean up two separate suspected sources of groundwater contamination and site
contamination.
March 1992                                 6            MYSTERY BRIDGE ROAD/HIGHWAY 20

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Environmental Progress
The immediate actions to provide bottled water until safe municipal water supplies could be
provided and to remove accessible surface contaminants have greatly reduced the potential
for exposure to hazardous substances at the Mystery Bridge Road/Highway 20 site while
cleanup activities are being completed.
Site Repository
Natrona County Library, 307 East Second Street, Casper, WY 82601
MYSTERY BRIDGE ROAD/HIGHWAY 20
March 1992

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                             GLOSSARY
                   Terms Used in the NPL Book
           This glossary defines terms used throughout the NPL Volumes. The terms and
           abbreviations contained in this glossary apply specifically to work performed
       under the Superfund program in the context of hazardous waste management. These
       terms may have other meanings when used in a different context. A table of common
       toxic chemicals found at NPL sites, their sources, and their potential threats is located
       on page G-15
Acids:  Substances, characterized by low pH
(less than 7.0), that are used in chemical manu-
facturing. Acids in high concentration can be
very corrosive and react with many inorganic
and organic substances. These reactions possi-
bly may 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 the
EPA and the parties potentially responsible for
site contamination. Under the terms of the
Order, the potentially responsible parties (PRPs)
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 responsible
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 the EPA,
directing the parties potentially responsible to
perform site cleanups or studies (generally, the
EPA does not issue Unilateral Orders for site
studies). This type of Order is not signed by the
PRPs and does not require approval by  a judge.

Aeration: A process that promotes  breakdown
of contaminants in soil or water by exposing
them to air.
Agency for Toxic Substances and Dis-
ease Registry (ATSDR): The Federal
agency within the U.S. Public Health Service
charged with carrying out the health-related
responsibilities of CERCLA.

Air Stripping:  A process whereby volatile
organic chemicals (VOCs) are removed from
contaminated material by forcing a stream of air
through the contaminated material in a pressur-
ized vessel. The contaminants are evaporated
into the air stream.  The air may be further
treated  before it is released into the atmosphere.

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.

Applicable or Relevant and Appropriate
Requirements (ARARs):  Federal, State, or
local laws which apply to Superfund activities at
NPL sites.  Both emergency and long-term
actions must comply with these laws or provide
sound reasons for allowing a waiver.  ARARs
must be identified for each site relative to the
characteristics of the site, the substances found
at the site, or the cleanup alternatives being
considered for the site.
                                          G-1

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GLOSSARY
Aquifer:  An underground layer of rock, sand,
or gravel capable of storing water within cracks
and pore spaces, or between grains. When
water contained within an aquifer is of sufficient
quantity and quality, it can be tapped and used
for drinking or other purposes.  The water
contained in the aquifer is called groundwater.
A "sole source aquifer" supplies 50 percent or
more of the drinking water of an area.

Artesian (Well): A well made by drilling into
the earth until water is reached, which, due to
internal pressure, flows up like a fountain.

Asbestos: A mineral fiber that can pollute air
or water and is known to cause cancer or
asbestosis when inhaled.

Attenuation: The naturally occurring process
by which a compound is reduced in concentra-
tion over time through adsorption, degradation,
dilution, or transformation.

Background Level: The amount of a sub-
stance typically found in the air, water, or soil
from natural, as opposed to human, sources.

Baghouse Dust: Dust accumulated in
removing particulates from the air by passing it
through cloth bags in an enclosure.

Bases: Substances characterized by high pH
(greater than 7.0), which tend to be corrosive in
chemical reactions. When bases are mixed with
acids, they neutralize each other, forming salts.

Berm:  A ledge, wall, or a mound of earth used
to prevent the migration of contaminants.

Bioaccumulate: The process by which some
contaminants or toxic chemicals gradually
collect and increase in concentration  in living
tissue, such as in plants, fish, or people, as they
breathe contaminated air, drink contaminated
water, or eat contaminated food.
Biological Treatment:  The use of bacteria
or other microbial organisms to break down
toxic organic materials into carbon dioxide and
water.

Bioremediation: A cleanup process using
naturally occurring or specially cultivated
microorganisms to digest contaminants and
break them down into non-hazardous compo-
nents.

Bog: A type of wetland that is covered with
peat moss deposits. Bogs depend primarily on
moisture from the air for their water source, are
usually acidic, and are rich in plant residue [see
Wetland].

Boom: A floating device used to contain oil
floating on a body of water or to restrict the
potential overflow of waste liquids from
containment structures.

Borehole: A hole that is drilled into the
ground and used to sample soil or ground-water.

Borrow Pit: An excavated area where soil,
sand, or gravel has been dug up for use else-
where.

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 generally is
mounded or sloped so water will drain off.

Carbon Adsorption: A treatment system in
which contaminants are removed from ground-
water and surface water by forcing water
through tanks containing activated carbon, a
specially treated material that attracts and holds
or retains contaminants.

Carbon Bisulfide:  A degreasing agent
formerly used extensively for parts washing.
This compound has both inorganic and organic
                                           G-2

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                                                                       GLOSSARY
properties, which increase cleaning efficiency.
However, these properties also cause chemical
reactions that increase the hazard to human
health and the environment.

Carbon Treatment: [see Carbon Adsorp-
tion].

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.

CERCLA: [see Comprehensive Environmen-
tal Response, Compensation, and Liability Act].

Characterization:  The sampling, monitoring,
and analysis of a site to determine the extent and
nature of toxic releases. Characterization
provides the basis for acquiring the necessary
technical information to develop, screen, ana-
lyze, and select appropriate cleanup techniques.

Chemical Fixation: The use of chemicals to
bind contaminants, thereby reducing the poten-
tial for leaching or other movement.

Chromated Copper Arsenate: An insecti-
cide/herbicide formed from salts of three toxic
metals: copper, chromium, and arsenic.  This
salt is used extensively as a wood preservative
in pressure-treating operations.  It is highly toxic
and water-soluble, making it a relatively mobile
contaminant in the environment

Cleanup: Actions taken to eliminate a release
or threat of release of a hazardous substance.
The term "cleanup" sometimes is used inter-
changeably with the terms remedial action,
removal action, response action, or corrective
action.

Closure: The process by which a landfill stops
accepting wastes and is shut down under Federal
guidelines that ensure the protection of the
public and the environment.

Comment Period: A specific interval during
which the public can review and comment on
various documents and EPA actions related to
site cleanup. For example, a comment period is
provided when the EPA proposes to add sites to
the NPL. Also, there is minimum 3-week
comment period for community members to
review and comment on the remedy proposed to
clean up a site.

Community Relations: The EPA effort to
establish and maintain two-way communication
with the public. The goals of community
relations programs include creating an under-
standing of EPA programs and related actions,
assuring public input into decision-making
processes related to affected communities, and
making certain that the Agency is aware of, and
responsive to, public concerns.  Specific com-
munity relations activities are required in
relation to Superfund cleanup actions [see
Comment Period].

Comprehensive Environmental Re-
sponse, Compensation, and Liability
Act  (CERCLA):  Congress enacted the
CERCLA, known as Superfund, in  1980 to
respond directly to hazardous waste problems
that may pose a threat to the public  health and
the environment. The EPA administers the
Superfund program.

Confluence:  The place where two bodies of
water, such  as streams or rivers, come together.

Confined Aquifer: An aquifer in which
groundwater is confined under pressure that is
significantly greater than atmospheric pressure.
                                          G-3

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GLOSSARY
Consent Decree: A legal document, ap-
proved and issued by a judge, formalizing an
agreement between the EPA and the parties
potentially responsible for site contamination.
The decree describes cleanup actions that the
potentially responsible parties are required to
perform, or the costs incurred by the govern-
ment that the parties will reimburse, and the
roles, responsibilities, and enforcement options
that the government may exercise in the event of
non-compliance by potentially responsible
parties. If a settlement between the EPA and a
potentially responsible party includes cleanup
actions, it must be in the form of a Consent
Decree.  A Consent Decree is subject to a public
comment period.

Consent Order: [see Administrative Order
on Consent].

Containment: The process of enclosing or
containing hazardous substances in a structure,
typically in a pond or a lagoon, to prevent the
migration of contaminants into the environment.

Contaminant: Any physical, chemical,
biological, or radiological material or substance
whose quantity, location, or nature produces
undesirable health or environmental effects.

Contingency Plan: A document setting
out an organized, planned, and coordinated
course of action to be followed in case of a
fire, explosion, or other accident that releases
toxic chemicals, hazardous wastes, or radioac-
tive materials into the environment.

Cooperative Agreement: A contract
between the EPA and  the States, wherein a State
agrees to manage or monitor certain site cleanup
responsibilities and other activities on a cost-
sharing basis.

Cost Recovery: A legal process by which
potentially responsible parties can be required
to pay back the Superfund program for money
it spends on any cleanup actions [see Poten-
tially Responsible Parties].

Cover: Vegetation or other material placed
over a landfill or other waste material.  It can
be designed to reduce movement of water into
the waste and to prevent erosion that could
cause the movement of contaminants.

Creosotes:  Chemicals used in wood pre-
serving operations and produced by distilla-
tion of tar, including polycyclic aromatic
hydrocarbons and polynuclear aromatic
hydrocarbons [see PAHs and PNAs]. Con-
taminating sediments, soils, and surface
water, creosotes may cause skin ulcerations
and cancer through prolonged exposure.

Culvert: A pipe used for drainage under a
road, railroad track, path, or through an embank-
ment

Decommission: To revoke a license to
operate and take out of service.

Degradation: The process by which a chemi-
cal is reduced to a less complex form.

Degrease: To remove grease from wastes,
soils, or chemicals, usually using solvents.

Deletion:  A site is eligible for deletion from
the NPL when Superfund response actions at the
site are complete. A site is deleted from the
NPL when a notice is published in the Federal
Register.

De minimis: This legal phrase pertains to
settlements  with parties who contributed  small
amounts of hazardous waste to a site. This
process allows the EPA to settle with small, or
de minimis contributors, as a single group rather
than as individuals, saving time, money, and
effort

Dewater:  To remove water from wastes, soils,
or chemicals.
                                          G-4

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                                                                        GLOSSARY
Dike: A low wall that can act as a barrier to
prevent a spill from spreading.

Dioxin:  An organic chemical by-product of
pesticide manufacture which is known to be one
of the most toxic man-made chemicals.

Disposal: Final placement or destruction of
toxic, radioactive, or other wastes; surplus or
banned pesticides or other chemicals; polluted
soils; and drums containing hazardous materials.
Disposal may be accomplished through the use
of approved secure landfills, surface impound-
ments, land farming, deep well injection, or
incineration.

Downgradient: A downward hydrologic
slope that causes groundwater to move toward
lower elevations.  Therefore, wells downgradi-
ent of a contaminated groundwater source are
prone to receiving pollutants.

Ecological Assessment: A study of the
impact of man-made or natural activity on living
creatures and their environment

Effluent: Wastewater, treated or untreated,
that flows out of a treatment plant, sewer, or
industrial outfall.  Generally refers to wastes
discharged into surface waters.

Emission:  Pollution discharged into the
atmosphere from smokestacks, other vents, and
surface areas of commercial or industrial facili-
ties.

Emulsifiers:  Substances that help in mixing
materials that do not normally mix; e.g., oil and
water.

Endangerment Assessment: A study
conducted to determine the risks posed to public
health or the environment by contamination at
NPL sites. The EPA or the State conducts the
study when a legal action is to be taken to direct
the potentially responsible parties to clean up a
site or pay for the cleanup. An endangerment
assessment supplements an investigation of the
site hazards.

Enforcement:  EPA, State, or local legal
actions taken against parties to facilitate
settlements; to compel compliance with laws,
rules, regulations, or agreements; or to obtain
penalties or criminal sanctions for violations.
Enforcement procedures may vary, depending
on the specific requirements of different
environmental laws and related regulatory
requirements.  Under CERCLA, for example,
the EPA will seek to require potentially
responsible parties to clean up a Superfund
site or pay for the cleanup [see Cost Recov-
ery].

Erosion: The wearing away of land surface
by wind or water. Erosion occurs naturally
from weather or surface runoff, but can be
intensified by such land-related practices as
farming, residential or industrial develop-
ment, road building, or timber-cutting. Ero-
sion may spread surface contamination to off-
site locations.

Estuary (estuarine): Areas where fresh
water from rivers and salt water from
near shore ocean waters are mixed. These
areas may include bays, mouths of rivers, salt
marshes, and lagoons. These water ecosys-
tems shelter and feed marine life, birds, and
wildlife.

Evaporation Ponds: Areas where  sewage
sludge or other watery wastes are dumped and
allowed to dry out.

Feasibility Study: The analysis of the
potential cleanup alternatives for a site. The
feasibility study usually starts as soon as the
remedial investigation is underway. In this
volume, the feasibility study  is referred to as a
site study [see  also Remedial Investigation].
                                           G-5

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GLOSSARY
Filtration: A treatment process for remov-
ing solid (paniculate) matter from water by
passing the water through sand, activated
carbon, or a man-made filter. The process is
often used to remove particles that contain
contaminants.

Flood Plain: An area along a river, formed
from sediment deposited by floods. Flood
plains periodically are innundated by natural
floods, which can spread contamination.

Flue Gas: The air that is emitted from a
chimney after combustion in the burner
occurs.  The gas can include nitrogen oxides,
carbon oxides, water vapor, sulfur oxides,
particles, and many chemical pollutants.

Fly Ash: Non-combustible residue that results
from the combustion of flue gases. It can
include nitrogen oxides, carbon oxides, water
vapor, sulfur oxides, as well as many other
chemical pollutants.

French Drain System: A crushed rock drain
system constructed of perforated pipes, which is
used to drain and disperse wastewater.

Gasification (coal): The conversion of soft
coal into gas for use as a fuel.

General Notice Letter:  [See Notice Letter].

Generator: A facility that emits pollutants
into the air or releases hazardous wastes into
water or soil.

Good Faith Offer: A voluntary offer, gener-
ally in response to a Special Notice letter, made
by a potentially responsible party, consisting of
a written proposal demonstrating a potentially
responsible party's qualifications and willing-
ness to perform a site study or cleanup.

Groundwater: Water that fills pores in soils
or openings in rocks to the point of saturation.
In aquifers, groundwater occurs in sufficient
quantities for use as drinking arid  irrigation
water and other purposes.

Groundwater Quality Assessment: The
process of analyzing the chemical characteris-
tics of groundwater to determine whether any
hazardous materials exist.

Halogens: Reactive non-metals, such as
chlorine and bromine. Halogens are very
good oxidizing agents and, therefore, have
many industrial uses. They are rarely found
by themselves; however, many chemicals
such as polychlorinated biphenyls (PCBs),
some volatile organic compounds (VOCs),
and dioxin are reactive because of the pres-
ence of halogens.

Hazard Ranking System (HRS): The
principal screening tool used by the EPA to
evaluate relative risks to public health and the
environment associated with abandoned or
uncontrolled hazardous waste sites. The HRS
calculates a score based on the potential of
hazardous substances spreading from the site
through the air, surface water, or groundwater
and on other factors such as nearby popula-
tion. The HRS  score is the primary factor in
deciding if the site should be on the NPL.

Hazardous Waste: By-products of society
that can pose a substantial present or potential
hazard to human health and the environment
when improperly managed. Hazardous waste
possesses at least one of four characteristics
(ignitability, corrosivity, reactivity, or toxic-
ity), or appears on special EPA lists.

Heavy Metals: Metallic elements with high
atomic weights, such as arsenic, lead, mercury,
and cadmium. Heavy metals are very hazardous
even at low concentrations and tend to accumu-
late in the food chain.

Herbicide: A chemical pesticide designed to
control or destroy plants, weeds, or grasses.
                                           G-6

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                                                                        GLOSSARY
Hot Spot: An area or vicinity of a site contain-
ing exceptionally high levels of contamination.

Hydrocarbons: Chemical compounds that
consist entirely of hydrogen and carbon.

Hydrology: The properties, distribution, and
circulation of water.

Hydrogeology: The geology of groundwater,
with particular emphasis on the chemistry and
movement of water.

Impoundment:  A body of water or sludge
confined by a dam, dike, floodgate, or other
barrier.

Incineration: A group of treatment technolo-
gies involving destruction of waste by controlled
burning at high temperatures, e.g., burning
sludge to reduce the remaining residues to a
non-burnable ash that can be disposed of safely
on land, in some waters, or in underground
locations.

Infiltration: The movement of water or
other liquid down through soil from precipita-
tion (rain or snow) or from application of
wastewater to the land surface.

Influent:  Water, wastewater, or other liquid
flowing into a reservoir, basin, or treatment
plant.

Injection Well:  A well  into which waste
fluids are placed, under pressure, for purposes
of disposal.

Inorganic Chemicals:  Chemical  sub-
stances of mineral origin, not of basic carbon
structure.

Installation Restoration Program:  The
specially funded program established in 1978
under which the Department of Defense has
been identifying and evaluating its hazardous
waste sites and controlling  the migration of
hazardous contaminants from those sites.
Intake: The source from where a water supply
is drawn, such as from a river or water body.

Interagency Agreement: A written agree-
ment between the EPA and a Federal agency
that has the lead for site cleanup activities,
setting forth the roles and responsibilities of the
agencies for performing and overseeing the
activities.  States often are parties to interagency
agreements.

Interim (Permit) Status: Conditions under
which hazardous waste treatment, storage,
and disposal facilities, that were operating
when regulations under the RCRA became
final in 1980, are temporarily allowed by the
EPA to continue to operate while awaiting
denial or issuance of a permanent permit. The
facility must comply with certain regulations
to maintain interim status.

Lagoon: A shallow pond or liquid waste
containment structure.  Lagoons typically are
used for the storage of wastewaters, sludges,
liquid wastes, or spent nuclear fuel.

Landfarm: To apply waste to land or incor-
porate waste into the surface soil, such as
fertilizer or soil conditioner. This practice
commonly is used for disposal of composted
wastes and sludges.

Landfill:  A disposal facility where waste is
placed in or on land. Sanitary landfills are
disposal sites for non-hazardous solid wastes.
The waste is spread in layers, compacted to the
smallest practical volume, and covered with soil
at the end of each operating day. Secure chemi-
cal landfills are disposal sites for hazardous
waste. They are designed to minimize the
chance of release of hazardous substances into
the environment [see Resource Conservation
and Recovery Act].

Leach, Leaching [v.t.]: The process by
which soluble chemical components are dis-
solved and carried through soil by water or
some other percolating liquid.
                                           G-7

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GLOSSARY
Leachate [n]:  The liquid that trickles through
or drains from waste, carrying soluble compo-
nents from the waste.

Leachate Collection System:  A system
that gathers liquid that has leaked into a landfill
or other waste disposal area and pumps it to the
surface for treatment.

Liner: A relatively impermeable barrier
designed to prevent leachate (waste residue)
from leaking from a landfill. Liner materials
include plastic and dense clay.

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 several of these phases.

Long-term Response Action: An action
which requires a continuous period of on-site
activity before cleanup  goals are achieved.
These actions typically  include the extraction
and treatment of groundwater and monitoring
actions.

Marsh:  A type of wetland that does not
contain peat moss deposits and is dominated by
vegetation. Marshes may be  either fresh or
saltwater and tidal or non-tidal [see Wetland].

Migration:  The movement of oil, gas, con-
taminants, water, or other liquids through porous
and permeable soils or rock.

Mill Tailings:  [See Mine Tailings].

Mine Tailings: A fine, sandy residue left from
mining operations.  Tailings often contain high
concentrations of lead, uranium, and arsenic or
other heavy metals.

Mitigation: Actions taken to improve site
conditions by limiting, reducing, or controlling
toxicity and contamination sources.
Modeling: A technique using a mathematical
or physical representation of a system or theory
that tests the effects that changes on system
components have on the overall performance of
the system.

Monitoring Wells: Special wells drilled at
specific locations within, or surrounding, a
hazardous waste site where groundwater can be
sampled at selected depths and studied to obtain
such information as the direction in which
groundwater flows and the types and amounts of
contaminates present.

National Priorities List (NPL): The
EPA's list of the most serious uncontrolled or
abandoned hazardous waste sites identified
for possible long-term cleanup under Super-
fund. The EPA is required to update the NPL
at least once a year.

Natural Attenuation: [See Attenuation].

Neutrals:  Organic compounds that have a
relatively neutral pH, complex structure and,
due to their organic bases, are easily absorbed
into the environment.  Water is the most
commonly known neutral, however, naphtha-
lene, pyrene, and trichlorobenzene also are
examples of neutrals.

Nitroaromatics:  Common components of
explosive materials, which will explode if
activated by very high temperatures or pres-
sures; 2,4,6-Trinitrotoluene (TNT) is a
nitroaromatic.

Notice Letter:  A General Notice Letter
notifies the parties potentially responsible for
site contamination of their possible liability. A
Special Notice Letter begins a 60-day formal
period of negotiation during which the EPA is
not allowed to start work at a site or initiate
enforcement actions against potentially respon-
sible parties, although the EPA may undertake
certain investigatory and planning activities.
                                           G-8

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                                                                       GLOSSARY
The 60-day period may be extended if the EPA
receives a good faith offer from the PRPs
within that period. [See also Good Faith Offer].

On-Scene Coordinator (OSC):  The
predesignated EPA, Coast Guard, or Depart-
ment of Defense official who coordinates and
directs Superfund removal actions or Clean
Water Act oil- or hazardous-spill corrective
actions.

Operation and Maintenance: Activities
conducted at a site after a  cleanup action is
completed to ensure that the cleanup or
containment system is functioning properly.

Organic Chemicals/Compounds:
Chemical substances containing mainly
carbon, hydrogen, and oxygen.

Outfall: The place where wastewater is
discharged into receiving  waters.

Overpacking: Process used for isolating
large volumes of waste by jacketing or encap-
sulating waste to prevent further spread or
leakage of contaminating materials. Leaking
drums may be contained within oversized
barrels as an interim measure prior to  removal
and final disposal.

Pentachlorophenol (PCP): A synthetic,
modified petrochemical that may be used as a
wood preservative because of its toxicity to
termites and fungi. It is a common component
of creosotes and can cause cancer.

Perched (groundwater):  Groundwater
separated from another underlying body of
groundwater by a confining layer, often clay or
rock.

Percolation:  The downward flow or filtering
of water or other liquids through subsurface
rock or soil layers, usually continuing down-
ward to groundwater.
Pesticide: A substance or mixture of sub-
stances intended to prevent, destroy, or repel any
pest. If misused, pesticides can accumulate in
the foodchain and contaminate the environment.

Petrochemicals: Chemical substances
produced from petroleum in refinery operations
and as fuel oil residues. These include
fluoranthene, chrysene, mineral spirits, and
refined oils. Petrochemicals are the bases from
which volatile organic compounds (VOCs),
plastics, and many pesticides are made. These
chemical substances often are toxic to humans
and the environment.

Phenols:  Organic compounds that are used in
plastics manufacturing and are by-products of
petroleum refining, tanning, textile, dye, and
resin manufacturing.  Phenols are highly poison-
ous.

Physical Chemical Separation: The
treatment process of adding a chemical to a
substance to separate the compounds for further
treatment or disposal.

Pilot Testing:  A small-scale test of a pro-
posed treatment  system in the field to determine
its ability to clean up specific contaminants.

Plugging: The process of stopping the flow of
water, oil, or gas into or out of the ground
through a borehole or well penetrating the
ground.

Plume:  A body of contaminated ground water
flowing from a specific source. The movement
of the groundwater is influenced by such factors
as local groundwater flow patterns, the character
of the aquifer in  which groundwater is con-
tained, and the density of contaminants [see
Migration].

Pollution: Generally, the presence of matter
or energy whose nature, location, or quantity
produces undesired health or environmental
effects.
                                          G-9

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GLOSSARY
Poly cyclic 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 immersion oils, and caulking
compounds. PCBs also are produced in certain
combustion processes.  PCBs are extremely
persistent in the environment because they are
very stable, non-reactive, and highly heat
resistant.  Chronic exposure to PCBs is believed
to cause liver damage.  It also is known to
bioaccumulate in fatty tissues.  PCB use and
sale was banned in 1979 with the passage of the
Toxic Substances Control Act

Polynuclear Aromatic Hydrocarbons
(PNAs): PNAs,  such as naphthalene, and
biphenyls, are a group of highly reactive organic
compounds that are a common component of
creosotes, which can be carcinogenic.

Polyvinyl Chloride (PVC): A plastic made
from the gaseous substance vinyl chloride. PVC
is used to make pipes, records, raincoats, and
floor tiles. Health risks from high concentra-
tions of vinyl chloride include liver cancer and
lung cancer, as well as cancer of the lymphatic
and nervous systems.

Potable Water: Water that is safe for drink-
ing and cooking.

Potentially Responsible Parties (PRPs):
Parties associated with a Superfund site who
may be liable for the cost of remedying the
release of hazardous substances. This may
include owners or operators of the site or trans-
porters who disposed of materials at the site.
PRPs may admit liability, or liability may be
determined by a court of law. PRPs may sign a
Consent Decree or Administrative Order on
Consent to participate in the site cleanup without
admitting liability.

Precipitation: The removal of solids from
liquid waste so that the solid and liquid portions
can be disposed of safely; the removal of
particles from airborne emissions. Electro-
chemical precipitation is the use of an anode or
cathode to remove the hazardous chemicals.
Chemical precipitation involves the addition of
some substance to cause the solid portion to
separate.

Preliminary Assessment: The process of
collecting and reviewing available information
about a known or suspected waste site or release
to determine if a threat or potential threat exists.

Pump and Treat: A groundwater cleanup
technique involving the extracting of contami-
nated groundwater from the subsurface and the
removal of contaminants, using one of several
treatment technologies.

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 envi-
ronment. Radon, the gaseous form of radium,
decays to form alpha particle radiation, which
cannot be absorbed through skin. However, it
can be inhaled, which allows alpha particles to
affect unprotected tissues directly and thus cause
cancer. Radiation also occurs naturally through
the breakdown of granite.

RCRA: [See Resource Conservation and
Recovery Act].

Recharge Area:  A land area where rainwater
saturates the ground and soaks through the earth
to reach an aquifer.
                                          G-10

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                                                                      GLOSSARY
Record of Decision (ROD): A public
document that explains which cleanup
alternative(s) will be used to clean up sites
listed on the NPL. It is based on information
generated during the remedial investigation
and feasibility study and consideration of
public comments and community  concerns.

Recovery Wells: Wells used to withdraw
contaminants or contaminated groundwater.

Recycle: The process of minimizing waste
generation by recovering usable products that
might otherwise become waste.

Remedial Action (RA): The actual con-
struction or implementation phase of a
Superfund site cleanup following the remedial
design [see Cleanup].

Remedial Design: A phase of site cleanup
where engineers design the technical specifi-
cations for cleanup remedies and technolo-
gies.

Remedial Investigation:  An in-depth
study designed to gather the data necessary to
determine the nature and extent of contamina-
tion at a Superfund site, establish the criteria
for cleaning  up the site, identify the prelimi-
nary alternatives for cleanup actions, and
support the technical and cost analyses of the
alternatives. The remedial investigation  is
usually done with the feasibility study. In this
volume, the remedial investigation is referred
to as a site study [see also Feasibility Study].

Remedial Project Manager (RPM):  The
EPA or State official responsible for oversee-
ing cleanup actions at the site.

Remedy Selection:  The selection of 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 con-
tamination will be naturally dispersed without
further cleanup activities, a "No Action"
remedy is selected [see Record of Decision].

Removal Action:  Short-term immediate
actions taken to address releases of hazardous
substances [see Cleanup].

Residual: The amount of a pollutant re-
maining in the environment after a natural or
technological process has taken place, e.g.,
the sludge remaining after initial wastewater
treatment, or the particulates remaining in air
after the air passes through a scrubber.

Resource Conservation and Recovery
Act (RCRA): A Federal law that established
a regulatory system to track hazardous sub-
stances from the time of generation to dis-
posal. The law requires safe and secure
procedures to be used in treating, transport-
ing, storing, and disposing of hazardous
substances. RCRA is designed to prevent
new, uncontrolled hazardous waste sites.

Retention Pond:  A small body of liquid
used for disposing of wastes and containing
overflow from production facilities. Some-
times retention ponds are used to expand the
capacity of such structures as lagoons the
store waste.

Runoff: The discharge of water over land
into surface water.  It can carry pollutants
from the air and land and spread contaminants
from its source.

Scrubber:  An air pollution control device
that uses a spray of water or reactant or a dry
process to trap pollutants in emissions.

Sediment: The layer of soil, sand, and
minerals at the bottom of surface waters such
as streams, lakes, and rivers, that absorbs
contaminants.
                                         G-11

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GLOSSARY
Seeps:  Specific points where releases of
liquid, usually leachate, form from waste
disposal areas, particularly along the lower
edges of landfills.

Seepage Pits: A hole, shaft, or cavity in
the ground used for the storage of liquids,
usually in the form of leachate, from waste
disposal areas.  The liquid gradually leaves
the pit by moving through the surrounding
soil.

Septage: Residue remaining in a septic tank
after the treatment process.

Sinkhole: A hollow depression in the land
surface in which drainage collects; associated
with underground caves and passages that
facilitate the movement of liquids.

Site Characterization: The technical pro-
cess used to evaluate the nature and extent of
environmental contamination, which is neces-
sary for choosing and designing cleanup mea-
sures and monitoring their effectiveness.

Site Inspection: The collection of informa-
tion from a hazardous waste site to determine
the extent and severity of hazards posed by the
site.  It follows, and is more extensive than, a
preliminary assessment. The purpose is to
gather information necessary to score the  site,
using the Hazard Ranking System, and to
determine if the site presents an immediate
threat that requires a prompt removal action.

Slag: The fused refuse or dross separated
from a metal in the process of smelting.

Sludge: Semi-solid residues from industrial
or water treatment processes that may be
contaminated with hazardous materials.

Slurry Wall: Barriers used to contain the flow
of contaminated groundwater or subsurface
liquids. Slurry walls are constructed by digging
a trench around a contaminated area and filling
the trench with an impermeable material that
prevents water from passing through it. The
groundwater or contaminated liquids trapped
within the area surrounded by the slurry wall
can be extracted and treated.

Smelter:  A facility that melts or fuses ore,
often with an accompanying chemical change,
to separate the metal. Emissions from smelters
are known to cause pollution.

Soil Gas:  Gaseous elements and compounds
that occur in the small spaces between par-
ticles of soil.  Such gases can move through
or leave the soil or rock, depending on
changes in pressure.

Soil Vapor Extraction: A treatment
process that uses vacuum wells to remove
hazardous gases from soil.

Soil Washing: A water-based process for
mechanically scrubbing  soils in-place to remove
undesirable materials. There are two ap-
proaches: dissolving or  suspending them in the
wash solution for later treatment by conven-
tional methods, and concentrating them into a
smaller volume of soil through simple particle
size separation techniques [see Solvent Extrac-
tion].

Stabilization: The process of changing an
active substance into inert, harmless material,
or physical activities at a site that act to limit
the further spread of contamination without
actual reduction of toxicity.

Solidification/Stabilization:  A chemical
or physical reduction of the mobility of
hazardous constituents. Mobility is reduced
through the binding of  hazardous constituents
into a solid mass with low permeability and
resistance to leaching.
                                           G-12

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                                                                       GLOSSARY
Solvent: A substance capable of dissolving
another substance to form a solution. The
primary uses of industrial solvents are as
cleaners for degreasing, in paints, and in
Pharmaceuticals. Many solvents are flam-
mable and toxic to varying degrees.

Solvent Extraction: A means of  separating
hazardous contaminants from soils,  sludges,
and sediment, thereby reducing the volume of
the hazardous waste that must be treated.  It
generally is used as one in a series of unit
operations. An organic chemical is  used to
dissolve contaminants as opposed to water-
based compounds, which usually are used in
soil washing.

Sorption: The action of soaking up or
attracting substances. It is used in many
pollution control systems.

Special Notice Letter: [See Notice Let-
ter].

Stillbottom:  Residues left over from the
process of recovering spent solvents.

Stripping: A process used to remove volatile
contaminants from a substance [see Air Strip-
ping].

Sumps: A pit or tank that catches liquid
runoff for drainage or disposal.

Superfund:  The program operated  under the
legislative authority of the CERCLA and
Superfund Amendments and Reauthorization
Act (SARA) to update and improve environ-
mental laws. The program has the authority to
respond directly to releases or threatened re-
leases of hazardous substances that may endan-
ger public health, welfare, or the environment
The "Superfund" is a trust fund that finances
cleanup actions at hazardous waste sites.
Surge Tanks: A holding structure used to
absorb irregularities in flow of liquids, including
liquid waste materials.

Swamp:  A type of wetland that is dominated
by woody vegetation and does not accumulate
peat moss deposits.  Swamps may be fresh or
saltwater and tidal or non-tidal [see Wetlands].

Thermal Treatment: The use of heat to
remove or destroy contaminants from soil.

Treatability Studies: Testing a treatment
method on contaminated ground water, soil, etc.,
to determine whether and how well the method
will work.

Trichloroethylene (TCE):  A stable, color-
less 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
Volatile Organic Compounds].

Unilateral [Administrative] Order:  [see
Administrative Order].

Upgradient: An upward hydrologic slope;
demarks areas that are higher than contaminated
areas and, therefore, are not prone to contamina-
tion by the movement of polluted groundwater.

Vacuum Extraction: A technology used to
remove volatile organic compounds (VOCs)
from soils. Vacuum pumps are connected to a
series of wells drilled to just above the water
table. The wells are sealed tightly at the soil
surface, and the vacuum established in the soil
draws VOC-contaminated air from the soil
pores into the well, as fresh air is drawn down
from the surface of the soil.
                                          G-13

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GLOSSARY
Vegetated Soil Cap: A cap constructed with
graded soils and seed for vegetative growth, to
prevent erosion [see Cap],

Vitrification: The process of electrically
melting wastes and soils or sludges to bind the
waste in a glassy, solid material more durable
than granite or marble and resistant to leaching.

Volatile Organic Compounds (VOCs):
VOCs are manufactured as secondary petro-
chemicals. They include light alcohols, acetone,
trichloroethylene, perchloroethylene,
dichloroethylene, benzene, vinyl chloride,
toluene, and methylene chloride. These poten-
tially 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.

Waste Treatment Plant:  A facility that
uses a series of tanks, screens, filters, and
other treatment processes to remove pollut-
ants from water.
Wastewater:  The spent or used water from
individual homes or industries.

Watershed: The land area that drains into a
stream or other  water body.

Water Table:  The upper surface of the
groundwater.

Weir:  A barrier to divert water or other liquids.

Wetland:  An area that is regularly saturated
by surface or groundwater and, under normal
circumstances, is capable of supporting
vegetation typically adapted for life in satu-
rated 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.

Wildlife Refuge: An area designated for
the protection of wild animals, within which
hunting and fishing are either prohibited or
strictly controlled.
                                           G-14

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                                                                              GLOSSARY
            Some Common  Contaminants at NPL Sites
 Contaminant
   Category
             Example
         Chemical Types
      Sources
    Potential Health
        Threats*
 Volatile Organic
 Compounds
 Creosotes
 Radiation
 {RadionuciSdes}
       Arsenic, Barium, Beryllium,
       Cadmium, Cobalt, Copper,
       Chromium, Lead, Manga-
       nese, Mercury, Nickel,
       Silver, Selenium, Zinc
       Trichloroethylene (TCE),
       Perchloroethylene (PCE),
       Acetone, Benzene,
       Ketone, Methyl chloride,
       Toluene, Vinyl Chloride,
       Dichlorethylene

       Chlordane, DDT 4-4, DDE,
       Heptachlor, Aldrin, Endrin,
       Atrazine, Dieldrin, Toxa-
       phene
       Polyaromatic hydrocar-
       bons (PAHs), Polynuclear
       aromatics (PNAs),
       Phenolic Tars, Pentachlo-
       rophenol (PCP)
       Radium-226, Radon,
       Uranium-235, Uranium-
       238
Electroplating, batteries,
paint pigments, photogra-
phy, smelting, thermom-
eters, fluorescent lights,
solvent recovery
Solvents and degreasers,
gasoline octane enhanc-
ers, oils and paints, dry
cleaning fluids, chemical
manufacturing.

Agricultural applications,
pesticide and herbicide
production
Electric transformers and
capacitors, insulators and
coolants, adhesives,
caulking compounds,
carbonless copy paper,
hydraulic fluids.
Wood preserving, fossil
fuel combustion
Mine tailings, radium
products, natural decay of
granites
                                                                  Tumors, cancers, and kidney,
                                                                  brain, neurological, bone and
                                                                  liver damage
Cancers,  kidney and liver
damage, impairment of the
nervous system resulting in
sleepiness and headaches,
leukemia

Various effects ranging from
nausea to nervous disorders.
Dioxin is a common by-product
of the manufacture of pesti-
cides and is both highly toxic
and a suspected carcinogen.
Cancer and liver damage.
Cancers and skin ulcerations
with prolonged exposure
Cancer
Sources:
Toxic Chemicals—What They Are, How They Affect You (EPA, Region 5)
Glossary of Environmental Terms (EPA, 1988}
'The potential for risk due to these contaminants is linked to a number of factors; for example, the length and level of exposure
and environmental and health factors such as age.
                                             G-15
                                                                * U.S.  G.P.O.:1993-341-835:81047

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