United States
                              Environmental Protection
                              Agency
                        Office of Research and Development (481)
                        Office of Solid Waste and
                        Emergency Response (5102G)
                       EPA B42-F-98-00>7
                       May 1998
                       www.epa.gov
                             RTDF    Update
                                                                        RTDF
                                                                    Remediation Technologies
                                                                     Development Forum
                             A Progress Report on the Remediation Technologies Development Forum (RTDF)
 INSIDE

 In Situ Flushing Team
 Establishes Subgroups    Page 1

 USAFToUse
 Accelerated Anaerobic
 Biodegradation for
 Dover AFB Cleanup      Page 2

 RTDF Cometabolic
 Bioventing Field Test
 Begins at Dover AFB     Page 3

 RCI Verification
 Statement To Be Signed
 for Lasagna™  Process    Page 3

 New Reports on
 Phase HA Lasagna™
 Demonstration on Web    Page 3

 IINERT Team Producing
 Soil/Site Survey         Page 3

 Joplin Site Shows Pb
 Reduction              Page 4

 Agencies To Coordinate
 PRB Long-Term
 Performance Research    Page 4

 PRB Team Focus of
 International Interest      Page 5

 Phytoremediation Team
 TCE Subgroup Seeking
 Industry Participants      Page 5

Alternative Covers
Workshop Focuses on
 RCRA Landfills          Page 5

 Phytoremediation Team
TPH Subgroup Holds
First Teleconference      Page 6
              S/ru FLUSHING TEAM
    Focus:
       • NAPLs
           • Solubilization/mobilization
              •• In ground water

 In Situ Flushing Team
 Establishes Subgroups
 The RTDF's In Situ Flushing Action Team has
 established four new subgroups to accomplish
 the work involved in a year-long project to
 encourage the use of in situ flushing technolo-
 gies for remediating non-aqueous phase liquids
 (NAPLs). The project's four primary goals
 reflected in the subgroups are to conduct an eco-
 nomic assessment, develop performance criteria,
 prepare a guide on best technical practices, and
 develop a full-scale design model.
 Economics and Recovery/Reuse
 The Economic Assessment and Remedial Agent
 Recovery/Reuse Subgroup is chaired by Dr. Jeff
• Harwell (University of Oklahoma). This sub-
 group focuses on:
 •    Identifying how to recover and reuse surfac-
     tants for different NAPLs (e.g.,
     chlorohydrocarbons) and summarizing the
     technological status and cost of these
     methodologies;
 •    Examining the pros and cons of using vari-
     ous "bottom-line" flushing cost measures
     and determining which measures are the
     most useful;

 •    Reviewing and comparing existing econom-
     ic analyses, identifying the assumptions
     used to generate them, and presenting this
     information in a "user-friendly" form; and
 •    Surveying state regulators to determine their
     attitudes toward surfactant injection and
    reinfection and using this information to
    produce "best-practice" guidelines.
 Endpoint Assessment

Dr. George Losonsky (IT Corporation) and Randy
Parker (U.S. EPA) chair the Endpoint
Assessment/Technical Performance Criteria
Subgroup. The subgroup's objectives are to:

 •   Develop guidelines for establishing
    acceptable target endpoints for contaminant
    concentrations and surfactant concentrations
    that remain in the soil after flushing is
    completed;

 •   Develop guidelines for predicting the ability
    to reach target endpoints and any potential
    negative outcomes; and

 •   Develop a framework for performance
    assessment.
Technical Practices
Dr. Gary Pope (University of Texas) chairs the
Technical Practices/Protocol Subgroup. This
group's objectives are to:

    Create a "living," up-to-date technical guide
    on both best practices and technology
    needs; and

    Design the technical guide for the Internet
    so that the document can be updated by the
    group and linked to relevant source docu-
    ments.
        About  the RTDF

   The Remediation Technologies Development
    Forum (RTDF), which was established in
    1992, is a consortium of partners from
  industry,government,and academia who are
    working together to develop safer,more
    effective, and less costly characterization
  and treatment technologies for remediation.
  For information on RTDF and Action Teams
        visit the RTDF Home Page at
           http://www.rtdf. org

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                                                                                   RTDF Update *  May 1998
The Subgroup already has developed a draft
outline for the two-volume technical guide,
using the Technology Practices Manual writ-
ten by the Advanced Applied Technology
Demonstration Facility (AATDF) as a
resource and "point of departure." Volume I
will address "What We Know Now" and will
be targeted for regulators and contractors.
Volume U will address "What We Still Need
To Do" and will be targeted for researchers.
Full-Scale Design
The Full-Scale Design Subgroup is chaired
by Dr. Michael Annable (University of
Florida). The Subgroup's objectives are to:
•   Develop a hypothetical full-scale in situ
    flushing design that will serve  as a
    model for others; and
•   Identify a full-scale design project in
    which this Subgroup might serve in an
    advisory role.
The Subgroup expects to produce a docu-
ment outlining steps involved in the full-scale
design process and significant issues, and to
share additional site designs through the In
Situ Flushing Action Team's home page on
the RTDF site on the World Wide Web. The
Subgroup is looking for sites that might qual-
ify as one of the first full-scale remediation
studies and intends to make frequent reports
on the RTDF Web site on the progress of the
search  and details of the design development
at the selected site or sites.
More details about the plans of these
Subgroups, including information on how to
participate, is available on the In Situ
Flushing Action Team's home page on the
RTDF  Web site. The In Situ Flushing Action
Team is planning its next meeting for
Summer 1998, and the agenda will include
updates on the Subgroup's work. For more
information, contact Action Team Co-chairs,
Dr. Lynn Wood (U.S. EPA/National Risk
Management Research Laboratory
[NRMRL]), 405-436-8552 or (e-mail)
wood.lynn@epa.gov, or Mr. Steve
Shoemaker (DuPont Engineering),  281-586-
2513 or (e-mail)
stephcn.h.shoemaker@usa.dupont.com.
       BlOREMEDIATION CONSORTIUM
   Focus;
       • Chlorinated solvents
           • Degradation
               • In soil and ground water

USAFTo Use Accelerated
Anaerobic  Biodegradation for
Dover AFB Cleanup
Based on the RTDF Bioremediation of
Chlorinated Solvents Consortium's
successful demonstration of the
effectiveness of accelerated anaerobic
biodegradation, the U.S. Air Force has
elected to use the process in full-scale
cleanup of a plume at the Dover Air Force
Base (DE) site. Full-scale implementation
currently is scheduled for 1999.
The goal of the Consortium's work related
to accelerated anaerobic biodegradation is
to understand thoroughly the operation,
cost, and performance of the process to
degrade chlorinated solvents in ground
water and to work out microbial parameters
(see Figure 1).  In situ anaerobic
dechlorination  is typically limited by the
availability of food and nutrients for
microbial growth. The Consortium's initial
work on accelerated anaerobic
biodegradation focused on determining
what these nutritional limitations are and
how to deliver additional nutrients to the
aquifer effectively. In addition, the early
studies determined which electron donors
and acceptors best support anaerobic
bioremediation; optimized the chlorocarbon
destruction rate; and determined what
factors control the degradation kinetics.
The Consortium installed a pilot accelerat-
ed anaerobic biodegradation system at
Dover AFB in 1996. The Consortium
installed three injection wells to deliver
additives and constructed three recovery
wells downgradient to provide the ground
water to be augmented. Together, the wells
created a hydraulically contained cell for
the test. In October 1996, the Consortium
injected additives. They included sodium
lactate as the substrate, or electron donor,
ammonium phosphate as the nutrient, and a
small amount of yeast extract.
By March 1997, TCE in the cell was com-
pletely degraded to cis-DCE by native
bacteria, but was not fully degrading to
non-toxic by-products. As a result of this
development, the Consortium elected to
augment a portion of the pilot with
        Injection
          Wells
                   • Substrate, Nutrients, and
                    Nonindigenous Bacteria
              Recovery
                Wells
                                     Ground Water Row
      Figure 1. Schematic diagram of accelerated anaerobic
      biodegradation.

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                                                                                  RTDF Update  *  May  1998
 among the participating agencies through
 each agency's principal investigator to
 ensure maximum synergism among the
 proposed projects.

 For more information, contact Action
 Team Co-chair Dr. Robert Puls (U.S.
 EPA/NRMRL) at 580-436-8543 or (e-
 mail) puls.robert@epa.gov.
 PRB Team Focus of
 International Interest
 Interest about the Permeable Reactive
 Barriers (PRB) Action Team and its activi-
 ties is high among several countries
 including Germany, the Netherlands, and
 the United Kingdom. Dr. Robert Puls (U.S.
 EPA/NRMRL), Co-Chair of the Action
 Team, met in February with researchers
 and environmental program managers from
 a number of European countries during a
 "Special Topics Technical  Session on
 Permeable Reactive Barriers" in Vienna,
 Austria. The session was part of the NATO
 Committee on the Challenges to Modern
 Society (CCMS)  Phase III Pilot Study
 Meeting, involving 14 countries engaged in
 the transfer of technological and scientific
 solutions among countries  with similar
 environmental issues and problems.
 As a result of the technical session and
 subsequent discussions, several European
 countries proposed formation of an
 European PRB Action Team, including
 possibly establishing some linkage with the
 RTDF Team in the United  States.
 Dr. Puls is continuing discussions with
 country representatives and providing addi-
 tional information in support of this
 initiative. A summary of proceedings from
 the Technical Session is expected to be
 available this Summer on the RTDF World
 Wide Web site. For more information, con-
tact Dr. Puls at 580-436-8543 or (e-mail)
puls.robert@epa.gov.

         PHYTOREMEDIATION TEAM
    Focus:
        • Solvents, TPH, PAH
           • Degradation/immobilization
               • In soil and ground water

 Phytoremediation Team TCE
 Subgroup Seeking Industry
 Participants

 The TCE in Ground Water Subgroup of the
 RTDF Phytoremediation of Organics
 Action Team is looking for potential indus-
 trial partners. This includes companies or
 associations in the drying cleaning, aero-
 space, electronics, and other industries that
 have used halogenated solvents heavily and
 have had to clean metal via vapor degreas-
 ing prior to painting or plating. Such
 potential partners also may be potentially
 responsible parties for sites with environ-
 mental contamination from
 trichloroethylene (TCE) and/or per-
 chloroethylene (PCE). The TCE Subgroup
 believes these companies and individuals
 would have an interest in phytoremediation
 because of its promise as a less expensive
 and more sustainable approach in dealing
 with halogenated solvents in soil and
 ground water.

 The Subgroup also is interested in working
 with DOE's Biomass Power Program and
 Biofuels Feedstock Development Program
 to find ways to leverage their expertise in
 industrial scale poplar tree plantations.
 These groups  focus on providing a sustain-
 able option for meeting projected needs for
 electric generating capacity and fuels.
While the DOE groups have different
objectives than the RTDF, the Subgroup
can benefit from lessons learned by these
groups, since they have many years' experi-
ence.

For more information about the plans,
activities, and partnership opportunities in
 the Phytoremediation Team's TCE
 Subgroup, visit the RTDF World Wide Web
 site or contact Subgroup Co-chairs Greg
 Harvey (U.S. Air Force) at 737-255-7716,
 extension 302 or (e-mail)
 harveygj@emsmtp.wpafb.af.mil, or Harry
 Compton (U.S. EPA) at 908-321-6751 or
 (e-mail) compton.harry@epa.gov.
 Alternative Covers Workshop
 Focuses on RCRA Landfills
 Members of the Phytoremediation of
 Organics Action Team Alternative Covers
 Subgroup participated in a February 1998
 workshop in Las Vegas, NV, focusing on
 issues involved in the application of
 alternative covers  to standard RCRA
 landfills. The workshop, sponsored by the
 Desert Research Institute, served as a
 followup to the Action Team's meeting on
 alternative covers  held in September 1997.
 Approximately 75 stakeholders participated
 in the workshop including U.S. EPA
 Headquarters, three EPA Regional Offices,
 eight states, DoD,  DOE, U.S. Department
 of Interior, local city and county
 governments, and private industry and
 consultants.

 The purpose of the workshop was to
 develop and formalize a demonstration
 project to assess alternative landfill covers.
 The Alternative Covers Assessment
 Program (ACAP) will establish a dispersed
 network of test facilities across the country.
 ACAP will focus on increasing the base of
 knowledge about alternative covers and
 addressing data gaps, including those
related to water infiltration rates, effects of
climatic changes, and long-term monitoring
techniques. In conjunction with field work,
the demonstration will establish and modify
existing numerical computer models for the
design and evaluation of alternative landfill
covers. A Cooperative Research and

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 RTDF  Update 4-  May 1998
•   orchard sites on which PbAsO4 pesti-
    cides have been applied
•   soils contaminated mainly from paint
    or leaded gasoline emissions
•   firing ranges
The IINERT Team wants to study soils and
sites with total Pb concentrations from 0.2
to 1 percent, although concentrations above
and below this range also may be desirable.
Other inorganic and organic contaminants
also may be present. The plan is to collect
surface soil samples in bulk (55 gal.) from
each of the Pb-contamination source
groups. The samples will include soils of
various textures and pH. All soils will be
characterized by standard methods  for
relevant soil properties and made available
to IINERT  Team members for additional
study.
As of March 16, 1998, information had
been collected on four types of sites (see
Figure 2). The IINERT Team is looking for
additional sites. If you can help, please
complete a survey form and send it to the
Team. The blank survey form is available
on the RTDF World Wide Web site. Just
click on the IINERT Soil-Metals Action
Team page, and click again on the
 "Technical Documents" button. Send com-
 pleted survey forms to Team Co-chair Dr.
 Bill Berti at DuPont Central Research and
 Development, Glasgow Site 301, P.O. Box
 6101, Newark, DE 19714-6101 or (e-mail)
 bill.berti@usa.dupont.com. For questions,
 contact Dr. Berti at 302-451-9224.
    Tvoe of site
Number
    Smelting/Mining sites	12
    Industrial or waste sites
        Battery Cracking	2
        Acid sludge disposal	1
    Metal
        Disposal sites 	3
    Lead paint	1
    Total
      .19
             Joplin Site Shows Pb
             Reduction
             Analysis of grass collected from the Joplin
             (MO) field research site six months after
             treatment application indicates that in-place
             Pb inactivation technologies are able to
             reduce plant Pb concentrations over control
             levels by up to 90 percent. The field study
             has been a cooperative effort of the IINERT
             Soil-Metals Action Team, U.S. EPA,
             Missouri Department of Natural Resources,
             University of Missouri, U.S. Department of
             Agriculture-Agriculture Research Service,
             the Doe Run Company, and DuPont
             Company.
             An animal dosing study, using weaning rats
             as a human surrogate, has begun. This
             study is using the same soils collected from
             the Joplin plots that have been used in the
             University of Missouri pig dosing study.
             Results from these  studies will help deter-
             mine the next step to translate in-place
             inactivation into a practical and accepted
             remediation technology.
             For more information about the Joplin field
             study, contact Action Team Co-Chair Dr.
             Bill Berti at 302-451-9224 or (e-mail)
             bill.berti@usa.dupont.com.
                 PERMEABLE REACTIVE BARRIERS TEAM
   Figure 2. Preliminary results from
   soil/site survey.
   Focus:
       • Chlorinated solvents, metals
           • Degradation/immobilization
              • In ground water

Agencies To Coordinate  PRB
Long-Term Performance
Research
The U.S. EPA, DOE, and Department of
Defense (DoD) recently agreed to  adopt a
coordinated approach for addressing long-
term performance issues for permeable
reactive barrier (PRB) projects. The RTDF's
Permeable Reactive Barriers Action Team
will serve as advisor to facilitate
coordination of the different agency efforts
and will establish uniform testing protocols
to be applied by all cooperating groups.
A January 1998 meeting at the Oak Ridge
National Laboratory brought together
researchers and research program managers
from the three agencies to discuss
interagency collaboration on research
focused on PRB long-term performance.
Participants agreed that funding requests
from each agency will be much less than
would be required for a single,
comprehensive program. During the
meeting, participants discussed specific
measurement and research tasks and
listed scientific issues related to
geochemistry, microbiology, hydrology,
sampling, analysis, and modeling. They
also identified topics of mutual concern
and expertise and requirements unique to
each organization.
Participants set the following objectives
for the proposed work: 1) to develop a
priori testing requirements that predict
the longevity of a PRB, 2) to develop
monitoring methods that will provide an
early warning of incipient barrier failure,
and 3) to develop long-term monitoring
protocols that minimize operation and
maintenance costs. They agreed that it
would be necessary to select sampling
and analytical methods that will ensure
direct comparability for all data to be
obtained. In addition, they agreed that
each agency would be chiefly responsible
for obtaining data at its own sites.
Participants recognized, however, that
each agency has unique monitoring
expertise and will need to be involved, in
some cases, in making specific measure-
ments at all of the walls being studied.
The DOE portion of the project will
focus on the installations at the Oak
Ridge Y-12 Plant and Kansas  City Plant.
DOE's Portsmouth X625 long-term pilot
study facility also may be addressed
depending upon the status of that project.
DOE and EPA will collaborate on work
at DOE's Rocky Flats Environmental
Technology Site. EPA's portion of the
project will focus on the U.S.  Coast
Guard Elizabeth City (NC) site and the
Denver Federal Center site.  DoD's
portion includes the Moffett Field site
 and may include others.  Data will be
 shared through regular conference calls
 and sharing of routine project reports.
 Final reports for specific milestones will
 be peer-reviewed by the principal
 investigators and their designees from the
 other participating agencies.
 Each agency is preparing proposals for
 research on the long-term performance of
 PRBs. These proposals will be shared

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                                                                                RTDF Update  +  May 1998
microorganisms that have the ability to fur-
ther degrade DCE and vinyl chloride. In
June 1997, cultures from the U.S.
Department of Energy's Pinellas (FL) Plant
were introduced into one of the three injec-
tion wells. In this area of the plume,
cis-DCE degraded to ethene, and good
mass balance was observed. The culture
took 90 days to become active, and three
more months to  achieve full degradation.
Initial concentrations were approximately
4,000 - 5,000 ppb of TCE and DCE com-
bined.

Operation and evaluation of the Phase I
pilot is scheduled to continue through
Spring 1998. The Consortium also plans to
assist in the scale-up of the technology at
Dover AFB. For more information, contact
Consortium Co-chair Dr. David Ellis
(DuPont Speciality Chemicals) at 302-892-
7445 or (e-mail)
ellisde@csoc.dnet.dupont.com.
Information about other Consortium pro-
jects is available on the Bioremediation
Consortium home page of the RTDF site on
the World Wide  Web.
RTDF Cometaboiic Bioventing
Field Test Begins at Dover
AFB

The first known field test of propane-stimu-
lated cometabolic bioventing began in
December 1997 at Dover AFB. The site
contains TCE, 1,2-DCE and 1,1,1-TCA in
the range of 1-50 mg/kg. The initial phase
of operation is acclimation of the test plot
to propane. Propane (0.1-1% v/v in air) is
periodically injected into the vadose zone
over a 1-3-month period. Eventually, the
soil microbes will begin to use propane as a
food source. The commencement of
propane use indicates that the chlorinated
solvents are being destroyed simultaneous-
ly. After acclimation, the system will be
operated for approximately nine months
using constant slow injection of propane
and air.

For more information, contact Greg Sayles
(U.S. EPA/NRMRL) at  513-569-7607 or (e-
mail) sayles.gregory@epa.gov.
         LASAGNA  PARTNERSHIP
   Focus:
       • TCE
           • Degradation
               • In low-permeability soils

RCI Verification Statement To
Be  Signed for Lasagna™
Process
Signing of a Rapid Commercialization
Initiative (RCI) Verification Statement for
the Lasagna™ process developed by
RTDF's Lasagna™ Partnership is expected
to be completed this month. The RCI is a
federal-state-private cooperative effort to
facilitate regulatory acceptance and expe-
dite the application  of new environmental
technologies.
The Verification Statement indicates the
acceptance by the signatories of cost and
performance data from the Lasagna™
Partnership's Phase  IIA-Vertical demonstra-
tion at the  U.S. Department of Energy's
(DOE's) Paducah Gaseous Diffusion Plant,
completed last year. The Statement is being
signed by representatives of DOE, U.S.
Department of Commerce, U.S. EPA,
Southern States Energy Board, MSB-
Technology Applications, Inc., the
California  Environmental Protection
Agency, DOE's Oak Ridge Operations
Office, Enviro-Chem Systems, Inc., and
Monsanto  Company. Letters of concur-
rence to this Verification Statement are
being provided by the appropriate environ-
mental  organizations in South Carolina,
Kentucky,  Ohio, Florida, Tennessee, and
Massachusetts.
Based on the results of the Phase I and II
demonstrations, which began in 1995, DOE
decided to  seek regulatory approval to use
the Lasagna™ process and cited it as the
preferred remedy in the proposed Record of
Decision (ROD) for a Solid Waste
Management Unit at the Paducah site.
A copy of the Verification Statement and
the final report of the Lasagna™ RCI par-
ticipants will be available on the Lasagna™
Partnership home page of the RTDF site on
the World Wide Web in May 1998. For
more information about the vertical
Lasagna™ process, contact Action Team
Co-chair Dr. B. Mason Hughes (Monsanto)
at 314-694-1466 or (e-mail) b.mason.hugh-
es@monsanto.com.
New Reports on Phase ISA
Lasagna™ Demonstration on
Web
The RTDF's Lasagna™ Partnership has
posted two new documents on the
Partnership's home page on the RTDF site
on the World Wide Web. These documents,
"Modeling and Iron Dechlorination
Studies" and "Iron Dechlorination Studies,"
report on work completed during the Phase
IIA-Vertical Lasagna™ demonstration,
completed in 1995, at DOE's Paducah (KY)
Gaseous Diffusion Plant. The new
documents and eight Phase I topical reports
can be viewed or downloaded from the
RTDF web site. Information on how to
obtain printed copies also is  available.
        [INERT SOIL-METALS TEAM
   Focus:
       • Lead
            Immobilization/inactivation
              • In soil
(INERT Team Producing
Soil/Site Survey

The In-Place Inactivation and Natural
Ecological Restoration Technologies (IIN-
ERT) Soil-Metals Action Team is
circulating a survey to help identify poten-
tial research field sites and to collect
sufficient quantities and types of soils for
research purposes. The Team has grouped
the types of sites to be included in these
studies based on the source of lead (Pb)
contamination, such as:
•    industrial or waste sites, including
    tetraethyl lead and ammunition
    manufacturing, burning grounds, and
    battery breaking
    mining and smelting operations

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United States
Environmental Protection Agency
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Official Business
Penalty for Private Use $300

EPA 542-F-98-007
May 1998
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                                                                                RTDF  Update  •  May  1998
Development Agreement (CRADA) will be
established among the demonstration
participants to perform the joint effort.
In addition to discussing ACAP, attendees
examined regulatory and industrial needs
associated with applying nonconventional
covers.
A complete summary of the meeting is
available on the Phytoremediation of
Organics Action Team page on the RTDF's
World Wide Web site. For additional infor-
mation about the ACAP demonstration,
contact Action Team Co-chair Steve Rock
(US. EPA/NRMRL), 513-569-7149 or (e-
mail) rock.steven@epa.gov.
Phytoremediation Team TPH
Subgroup Holds First
Teleconference
The Phytoremediation of Organics Action
Team has formed a subgroup to focus on
degradation of petroleum hydrocarbons in
near-surface soils.
The group held its first conference call on
March 18. Efforts will focus on the use of
plants to degrade petroleum-contaminated
soils which  occur at petroleum refining,
storage, transfer, and disposal sites. Some
of the sites that could be examined by the
group already have been identified. A mis-
sion statement has been proposed for the
group which is aimed at combining exper-
tise, technologies, and resources to conduct
phytoremediation field tests for degradation
of petroleum hydrocarbons. The object of
this work is to develop guidelines for future
applications, and gain public and regulatory
acceptance. Specific topics for discussion
include the development of a standardized
protocol for evaluation of plant suitability
for phytoremediation of TPHs, and the
gathering of available information in the
open and grey literature applicable to phy-
toremediation of TPHs. The TPH
phytoremediation subgroup is likely to
meet at the IBC conference in Houston this
June 22-25.

A summary of the March 18 teleconference
call is available on the Phytoremediation of
Organics Action Team's page on the
RTDF's World Wide Web site. For more
details, contact Action Team Co-Chair and
Subgroup Chair Lucinda Jackson (Chevron)
at 510-242-1047 or (e-mail)
luaj@chevron.com, Subgroup Chair Phil
Sayre (U.S. EPA) at 202-260-9570 or (e-
mail) sayre.phil@epa.gov, or Action Team
co-chair Steve Rock at 513-569-7149 or (e-
mail) rock.steven@epa.gov.

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