&EPA
United States
Environmental Protection
Agency
Office of Research and Development (481)
Office of Solid Waste and
Emergency Response (5102G)
EPA542-F-96-010B
September 1996
Bioremediation of Chlorinated
Solvents Consortium
KTDF
Remediation Technologies
Development Forum
RTDF Action
Teams
Bioremediation Consortium
Lasagna Partnership
Permeable Barriers Action
1
Team
Sediments Remediation
Action Team
IINERT Soil-Metals Action
Team
What is the Bioremediation Consortium?
The Bioremediation of Chlorinated Solvents Consortium is one of five Action
Teams of the Remediation Technologies Development Forum (RTDF). The
RTDF was created in 1992 by the U.S. Environmental Protection Agency (EPA)
to foster collaboration between the public and private sectors in developing
innovative solutions to solve complex hazardous waste problems of mutual
concern. The Bioremediation Consortium was established in May 1993, when
representatives from various companies, universities, the EPA, the Department
of Defense (DOD), and the Department of Energy (DOE) met to discuss their
shared interest in developing in-situ bioremediation technologies to degrade
chlorinated solvents in soils and groundwater. Since that first meeting, the
industrial partners of the Bioremediation Consortium—DuPont, Dow, General
Electric, Monsanto, Zeneca, and Ciba-Geigy—signed a research agreement in
September 1994. Agreements were then negotiated with EPA, the Air Force,
and DOE to facilitate collaboration between the public and private sectors on
the planned research projects. Two additional companies, Beak International
and ICI Americas, joined the Bioremediation Consortium in Spring 1996.
Shortly after the Consortium was formed, they began developing a comprehen-
sive research plan to test and evaluate the effectiveness of three complimentary
in-situ bioremediation processes for degrading chlorinated solvents—intrinsic
bioremediation, accelerated anaerobic degradation, and cometabolic
bioventing. The Bioremediation Consortium initiated three Phase I field tests at
Dover Air Force Base (AFB) in Dover, Delaware, in early 1995. Planning is
underway to conduct Phase II field studies for each of the three processes at
another site.
What is the Problem of Concern?
Chlorinated solvents are among the most common contaminants resulting from
industrial and government operations. Used as solvents and degreasers, they
are typically found in the soils and groundwater adjacent to manufacturing,
maintenance, and service installations around the world. Although complete
degradation of chlorinated solvents to harmless end products is known to occur,
a better understanding of how to predict and manage these degradation proc-
esses is needed to ensure their use as cost-effective, practical solutions.
What is the Mission of the
Bioremediation Consortium?
The mission of the RTDF Bioremediation Consortium is to accelerate the
development of the most cost-effective in-situ bioremediation processes for
degrading chlorinated solvents. To accomplish this mission, each of the
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Consortium members jointly participate in the research,
development, demonstration, and evaluation efforts
necessary to achieve public and regulatory acceptance of
these biological processes. Consortium members
contribute personnel, equipment, laboratory facilities, and
funding needed to complete the Consortium's research,
development, and demonstration mission. This
unprecedented collaboration encourages the validation of
these innovative bioremediation processes by the
regulatory agencies to allow their implementation
nationwide. In addition, the data generated and experience
gained by the Consortium in conducting these field studies
will be used to develop guidelines for using these
technologies at other contaminated sites.
What Processes will be
Studied?
The Consortium focuses on three in-situ biore-
mediation processes: cometabolic bioventing,
(for treatment in the vadose zone), intrinsic
bioremediation (for treatment of the bulk of a
plume), and accelerated anaerobic biodegrada-
tion (for treatment of more concentrated areas of
a plume).
Cometabolic Bioventing. Laboratory studies
have shown that aerobic degradation of trichlo-
roethene (TCE) in soils occurs most easily in the
presence of a cometabolite, such as toluene, pro-
pane, or methane. Cometabolic bioventing uses a
technique, similar to methods currently used in
bioventing technology, to efficiently deliver
oxygen and a cometabolite to the vadose zone in
order to remediate TCE. This technology
appears to have great promise. The objective of the
RTDF cometabolic bioventing study is to develop a cost-
effective process that promotes the cometabolic bioreme-
diation of TCE and other chlorinated solvents. The
Consortium initiated the Phase I Cometabolic Bioventing
Study at Dover AFB, where TCE is present in sandy soil.
Intrinsic Bioremediation. Intrinsic bioremediation, or
natural attenuation, of chlorinated solvents in groundwa-
ter can occur at sites where indigenous microbial popula-
tions are present that can degrade these chemicals.
Certain microorganisms are capable of detoxifying
chlorinated methanes, ethylenes, ethanes, and aromatics
by reductive dehalogenation or by oxidation. These
processes can result in complete biodegradation to
innocuous end products. The objective of the natural
attenuation research effort is to quantitatively determine
where, at what rate, and under what conditions natural
attenuation occurs. Data from both field and laboratory
studies will be used to develop a predictive natural
attenuation model that will relate the measured degradation
rates to the expected time course and outcome of intrinsic
bioremediation. The Consortium initiated the Phase I
Intrinsic Bioremediation Study at Dover AFB, where
chloroethenes are present in shallow groundwater. Key to
selection of Dover AFB as the test site was the presence of
an active microbial population, which was evidenced by
the detection of degradation products at the site.
Accelerated Anaerobic Biodegradation. The rate of
in-situ anaerobic dechlorination is typically limited by the
Cometabolic Bioventing
Low Rate Air and
Cometabolite Injection
Soil Gas Groundwater
Monitor Monitoring Well
availability of food and nutrients for microbial growth. The
purpose of the accelerated anaerobic degradation study is to
discover what these nutritional limitations are and how to
effectively deliver nutritional additions to the aquifer in
order to facilitate the use of this technology at other sites.
This study will also aim to: determine which electron donors
and acceptors best support anaerobic bioremediation; opti-
mize the chlorocarbon destruction rate; determine what
factors control the degradation kinetics; and gather cost and
performance data. The Bioremediation Consortium has
begun a Phase I field study to test the accelerated anaerobic
process at Dover AFB.
The three technologies under investigation are environmen-
tally friendly-these in-situ processes cause minimal distur-
bance to the site, requiring few surface structures. They also
offer the benefit of reducing remediation costs over the
conventional method of pumping and treating.
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What Are the Consor-
tium Members' Roles ?
Every Consortium member plays a speci-
fic role in the collaborative research efforts
for the three bioremediation processes.
Each organization brings particular knowl-
edge and expertise, as well as the labora-
tory research, field studies, and resources
necessary to conduct the projects and
evaluate the effectiveness of the technolo-
gies.
The companies are sharing proprietary
information, patented technologies, and
their collective understanding and experi-
ence in bioremediation mechanisms and
kinetics, hydrogeology, and nutrient deliv-
ery systems to support the development
and testing of the three bioremediation
processes.
EPA's National Risk Management Research
Laboratory (NRMRL) in Cincinnati, Ohio,
is applying its knowledge and experience in
developing bioventing processes to support the laboratory
and field testing efforts for the cometabolic bioventing
study. Under a contract to EPA, The Scientific Consulting
Group provides technical and logistical support to the
Consortium. The Air Force brings its experience in
bioremediation and bioventing, as well as support for site
characterization and field work at Dover AFB. DOE is
applying its substantial bioremediation expertise and
laboratory experience, as well as tools for microbial
characterization, to support these studies.
What Activities Have Been
Completed?
The three technologies have been identified as the
remediation methods of choice in the Record of Decision
(ROD) for the specific sites at Dover AFB. Data from the
first year of the Phase I field and laboratory studies are
being analyzed by Consortium members. Extensive
geological and hydrological characterization efforts have
been completed to provide significant insight into the
subsurface conditions. Initial laboratory biodegradation
studies in batch, column, fed batch, and differential soil
bioreactors have been completed for each technology.
Microbial characterization efforts also have been initiated to
determine the nature of the indigenous microorganisms
responsible for degrading chlorinated solvents at the site. A
Intrinsic Bioremediation and
Accelerated Anaerobic Biodegradation
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number of characterization techniques, such as Most
Probable Number (MPN), direct count, Phospholipid Fatty
Acid Analysis (PLFA), and molecular approaches (16s
RNA) have been employed to this end. The Consortium also
initiated modeling efforts to develop a tool that will help
predict the performance of each of the bioremediation
processes at other sites.
In addition, the Consortium is collaborating with the
Western Governors Association's (WGA) Interstate
Technology and Regulatory Cooperation (ITRC) subgroup.
The WGA/ITRC will assist with the development and
validation of protocols for each of the three technologies,
which will facilitate the transfer of these biological
processes to other sites.
What Activities Are Planned?
Research efforts on the three Phase I projects will continue
until 1998. The Strother Field Industrial Park site in
Winfield, Kansas, has been selected for the Phase II
Accelerated Anaerobic Biodegradation Study and the
Phase II Intrinsic Bioremediation Study. Complementary
efforts will be undertaken to validate the conclusions
drawn from Phase I. The Consortium is currently ana-
lyzing characterization data on Hill AFB to determine if
that site is appropriate for the Phase II Cometabolic
Bioventing study.
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What are the Funding Sources ?
EPA provides the necessary funds and staff to support and facilitate
Bioremediation Consortium meetings, as well as meetings of the other RTDF
Action Teams. Staffing, funding, and equipment needed to develop and test
the three bioremediation processes are being provided by the Bioremediation
Consortium members. Both EPA and the Air Force work through a
Cooperative Research and Development Agreement, which allows govern-
ment agencies to work with industry on collaborative research efforts. DOE
has contributed significant funding for the intrinsic bioremediation and
accelerated anaerobic biodegradation Phase I projects. The Phase I cometa-
bolic bioventing field study has been primarily funded by EPA, the Air Force,
andZeneca.
Who Are the Consortium Members?
KTDF
Remediation Technologies
Development Forum
Beak International
Ciba-Geigy Corporation
Dow Chemical Company
DuPont
General Electric
ICI Americas
Monsanto Company
Zeneca, Inc.
U.S. Air Force
U.S. Department of Energy
U.S. Environmental Protection Agency
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Beak International
Dave Major
(519)763-2325
dmaj or@beak. com
Ciba-Geigy
Sam Sury
(910)632-2017
sam.sury@usgr.mhs.ciba.com
Dow Chemical
Gary M. Klecka
(517)636-3227
gmklecka@dow. com
DuPont
David E. Ellis
Steering Committee Chairperson
(302) 892-7445
ellisde@csoc.dnet.dupont.com
GE
Joseph Salvo
(518)387-6123
salvo@crd.ge.com
ICI Americas
Martin Bell
(011)44-1928-517-875
martin bell@ici.co.uk
Monsanto
Michael A. Heitkamp
(314)694-3296
maheit@ccmail.monsanto. com
Zeneca
Malcolm Watts
(302) 886-3085
U.S. Air Force
Catherine Vogel
(904)283-6208
cathy_vogel@ccmail.aleq. tyndall.af.mil
U.S. Department of Energy
Skip Chamberlain
(301)903-7248
grover.chamberlain@em.doe.gov
U.S. EPA/National Risk
Management Research Laboratory
Gregory D. Sayles
(513)569-7607
say les. gregory @epamail. epa. go v
Would You Like
More
Information?
For mo
For more information on the
Bioremediation Consortium and the other
RTDF Action Teams, please contact:
J m
Robert Olexsey
U.S. Environmental Protection Agency
26 West Martin Luther King Drive
Cincinnati, OH 45268
Tel: (513)569-7861
Email: olexsey.bob@epamail.epa.gov
Walter Kovalick, Jr., Ph.D.
U. S. Environmental Protection Agency
401M Street, SW (5102G)
Washington, D.C. 20460
Tel: (703) 603-9910
Email: kovalick.walter@epamail.epa.gov
To request other RTDF factsheets, please
write/fax to:
EPA/NCEPI
11305 Reed Hartman Highway, Suite 219
Cincinnati, OH 45241
Fax: (513)489-8695
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