United States
Environmental Protection
Agency
Research and Development (481)
Solid Waste and
Emergency Response (5102G)
EPA542-F-97-016
November 1997
&ERA RTDF
Remediation Technologies
Development Forum
A Progress Report on the Remediation Technologies Development Forum (RTDF)
INSIDE
Lasagna™ Process
Preferred Remedy
for DOE Site Page 1
RTDF Members Meet Page 2
Long-Term Performance
of In Situ Permeable
Reactive Barriers Is
Research Priority Page 2
Early Results of
IINERT Field Study
Encouraging Page 3
Phytoremediation Team
Sponsors Alternative
Cover Workshop Page 3
In Situ Flushing Team
Holds Organizational
Meeting Page 3
Bioremediation
Demonstrations
Continue Page 4
Resources Page 4
About the RTDF
The Remediation Technologies
Development Forum (RTDF), which
was established in 1992,is a consor-
tium of partners from industry, gov-
ernment, and academia who are
working together to develop safer,
more effective, and less costly haz-
ardous waste characterization and
treatment technologies. For infor-
mation on RTDF and Action Teams
visit the RTDF Home Page at
h ttp://www.rtdf. org
Lasagna™ Process Preferred
Remedy for DOE Site
The U.S. Department of Energy (DOE) has
decided to include the Lasagna™ Process in its
Record of Decision (ROD) for cleanup of a site
at the agency's Paducah Gaseous Diffusion
Plant (PGDP) and is pursuing regulatory
approval through the CERCLA process. If
approved, the vertical configuration of the tech-
nology will be used to clean up a Solid Waste
Lascuina™
Management Unit at PGDP containing 10,000
cubic yards of contaminated material. This is the
first time Lasagna™ has been chosen for actual
cleanup of a site and a major milestone in its
development by the RTDF's Lasagna™
Partnership.
DOE based its decision on results of two suc-
cessful field demonstrations of the process at
the Paducah site. In the Phase l-Vertical demon-
stration, completed in 1995, the Lasagna™
process removed 98 percent of TCE from a tight
clay soil, and some samples showed removal of
more than 99 percent. The most recent demon-
stration (Phase HA-Vertical), which incorporated
the use of reactive treatment zones to destroy
TCE in situ, was similarly successful. This
demonstration resulted in 99.7% TCE removal
(from the 2-ft zone), provided information on the
optimal spacing of treatment zones, produced
evidence that Lasagna™ is capable of handling
dense non-aqueous phase liquids (DNAPLs),
and provided data with which to substantiate
technology cost estimates.
The Phase 11 A-Vertical demonstration began in
August of 1996, covered an area of 30 feet by
21 feet, and reached a depth of 45 feet. Before
the test began, the average TCE concentration in
the soil was about 35 ppm, but local concentra-
tions varied from a few ppm to almost 400 ppm.
The higher value is equivalent to twice the solubil-
ity of TCE in the pore water. The high levels of
TCE strongly indicated the presence of pure TCE
droplets (DNAPLs) in the soil. For the demonstra-
tion, an electrode was placed at each end of the
test site. Three treatment zones were placed at 2-
foot, 5-foot, and 7-foot intervals between the elec-
trodes. These different intervals were created to
help determine the optimal spacing for cleanup
using the Lasagna™ process. Each treatment
zone measured 21 feet across, 1.5 inches thick,
and 45 feet deep. A mixture of coke-like granular
carbon and iron filings was used for the electrode
material and a mixture of kaolin clay and iron fil-
ing was used for the treatment zone material.
The demonstration presented two major and
unexpected challenges to the Lasagna™ process.
First, TCE contamination was at least 30 times
higher in the soil than indicated in pre-test soil
sampling. Second, the demonstration team
encountered an undefined sand lens (at a depth of
20 to 25 feet), which may have caused unpre-
dictable hydraulic movement at the test site.
Despite these complications, the test proceeded
smoothly. Voltage, temperature, and electroosmot-
ic water flow were consistent with small-scale data
and computer modeling predictions. Samples
taken after about 10 months of operation showed
an average TCE level of 0.1 ppm, which is sub-
stantially lower than the Kentucky soil cleanup tar-
get, in the soil region bracketed between the 2-ft-
spacing treatment zones.
These results were especially significant consider-
ing the tremendous amount of TCE in the soil and
that only two pore volumes of water exchange had
occurred. Well water samples and analysis of
reaction products also suggested DNAPL move-
ment and in situ degradation by iron filings.
This ability to handle DNAPLs significantly
expands the scope of potential Lasagna™ applica-
tions.
Based on the data obtained, DuPont determined
that the cost of the Lasagna™ treatment is in the
range of $50-100/yd3 for cleanup of a 1-acre or
larger site. The Lasagna™ Partnership is looking
for sites for additional demonstrations of the
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RTDF Update • November 1997
process and moving forward on commer-
cfalization activities.
The Partnership also is continuing its
efforts to develop the horizontal configu-
ration of the Lasagna™ process. This
work is led by the U.S. EPA National Risk
Management Resource Lab (NRMRL)
working with the University of Cincinnati.
Two small-scale horizontal cells have
been installed in TCE contaminated soil
at Rickenbacker Air National Guard Base
In Columbus, OH. In addition, the infra-
structure for two large-scale horizontal
calls has been installed in TCE contami-
nated soil at Offutt Air Force Base in
Omaha, NE. Tests at both locations will
continue through 1998.
For more Information about the vertical
configuration of the Lasagna™ process,
contact Dr. Sa V. Ho, (Monsanto), 314-694-
5179 or Dr. B. Mason Hughes, (Monsanto),
at 314-694-1466. For information about
work on the horizontal configuration of
Lasagna™, contact Dr. Michael Roulier,
(U.S.EPA/ NRMRL), 513-569-7796.
RTDF Members Meet
The Remediation Technologies
Development Forum (RTDF) meets
October 15-16, in Evanston, IL. Meeting
participants are expected to include rep-
resentatives of government, industry, and
academia currently involved in one or
more of the RTDFs seven action teams
as well as others Interested in coopera-
tive efforts to develop more permanent,
cost-effective technologies for remediat-
ing hazardous wastes.
Since Hs inception in 1992, the RTDF has
grown to include seven action teams, oon-
sortla, and partnerships. They are: the
Bioremediation Consortium, the In-Place
Inactivation and Natural Ecological
Restoration Technologies (I INERT) Soil-
Metals Action Team, the In Situ Flushing
Action Team, the Lasagna™ Partnership, the
Permeable Reactive Barriers Action Team,
the Phytoremediation of Organics Action
Team, and the Sediments Remediation
Action Team. Each of these self-managed
teams uses the combined expertise, facilities,
and resources of its members to develop,
test, and evaluate in situ technologies to
address high-priority problems. The agenda
for the meeting includes an update on the
research and demonstration activities of each
team. In addition, the meeting features dis-
cussion of cross-cutting issues, including the
status of commercial development of innova-
tive technologies, funding opportunities for
public-private partnerships, and cooperative
efforts with the states through the Interstate
Technology Regulatory Cooperation (ITRC)
Working Group.
A full report on the meeting will be available
early in November on the RTDF's World
Wide Web site. For more information about
the RTDF, contact Co-Chairs Dr. Walter W.
Kovalick (U.S. EPA Technology Innovation
Office) 703-603-9910 or Robert Olexsey
(U.S. EPA/NRMRL) 513-569-7861.
Long-Term Performance of
In Situ Permeable Reactive
Barriers Is Research Priority
The Steering Committee of the Permeable
Reactive Barriers Action Team has identified
long-term performance issues associated
with permeable reactive barriers (PRBs) as
a priority for continued research to advance
the acceptance and implementation of this
innovative and cost-effective technology.
RTDF
Latest Developments
Welcome to the
Remediation Technologies
Development Forum
(RTDF) Web Site
http://rtdf.org
The Steering Committee is developing an
unified approach for addressing this need,
which includes leveraging resources from
DOE, DOD, EPA, and other sources and
integrating ongoing collaborative research
by of these agencies and researchers in
industry and academia.
Use of PRBs is an in situ approach for
remediating ground water contamination
that combines subsurface fluid flow man-
agement with a passive chemical treat-
ment zone. Removal of contaminants from
the ground-water plume is achieved by
altering the chemical conditions of the
plume as it moves through the reactive
barrier. Extensive research over the last
few years has improved our understanding
of the mechanisms and kinetics involved
in the removal of chlorinated solvent com-
pounds in such in situ treatment systems.
However, actual field implementation has
been somewhat slow, due in large part to
the risks and uncertainties associated with
long-term performance. Pilot and commer-
cial installations to date have proven that
PRBs can be cost-effective and efficient
but have provided few data on the long-
term performance.
The Steering Committee intends to use
several sites where PRBs have been
installed in the last two years, including
the U.S. Coast Guard site near Elizabeth
City, North Carolina, to focus future
research efforts. Action Team members
from EPA and the University of Waterloo
are the primary research investigators at
this site, where long-term performance is
a primary research objective. The
Steering Committee's objective is to eval-
uate long-term performance issues, using
the same analysis methods at three to
five sites, and to develop cost-effective
and efficient protocols to monitor these
systems over time.
Information about pilot and full-
scale PRB systems is avail-
able in Permeable Reactive
Subsurface Barriers for the
Interception and Remediation
of Chlorinated Hydrocarbon
and Chromium (VI) Plumes in
Ground Water (EPA/600 /F-
97/008). To order this fact
sheet, contact the U.S. EPA
Center for Environmental
Research Information (CERI),
513-569-7562. A copy also
may be downloaded from the
Internet at http://www.epa.gov/
ada/kerrlab. For more infor-
mation about the Permeable
Reactive Barriers Action Team,
contact Dr. Robert Puls, U.S.
EPA/NRMRL, 405-436-8543.
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RTDF Update 4- November 1997
Early Results of IINERT
Field Study Encouraging
Preliminary results of a field study at a
site in Joplin, MO, indicate that the addi-
tion of phosphorus (P) may significantly
reduce the bioavailability of lead (Pb) in
Pb-contaminated soils. The field study
was initiated by the In-place Inactivation
already have collected samples of soil
treated in the field with 0.5% and 1.0% P
for analysis using the swine model to
measure Pb-bioavailability. The research
team is in the process of collecting addi-
tional plant and soil samples. Plants will
be analyzed for elemental concentrations
in their tops, including concentrations of
and Natural Ecological Restoration
Technologies (IINERT) Soil-Metals
Action Team in cooperation with the U.S.
EPA, Missouri Department of Natural
Resources (MDNR), University of
Missouri, the U.S. Department of
Agriculture-Agricultural Research
Service (USDA-ARS), the Doe Run
Company, and DuPont-Company. The
one-acre test site is in an urban area
three to four blocks away from the site of
a former smelter site.
Initial results are from studies using soil
with a total Pb concentration of 4,000
ppm that was treated in the laboratory.
University of Missouri and MDNR
researchers used immature swine, dosed
with treated and untreated soil from the
site, to measure changes in Pb-bioavail-
ability. This study showed that the appli-
cation of 1% P to the soil significantly
reduced Pb-bioavailability, compared to
untreated soil from the site.
Researchers at the USDA-ARS have
conducted similar studies with the same
laboratory-treated soil using weaning
rats. Their studies showed that the appli-
cation of 1% P alone, and in combination
with 2.5% Fe (as Iron Rich), significantly
reduced soil Pb-bioavailability, as com-
pared to the untreated soil.
There also is evidence that reductions in
Pb-bioavailability in soils treated in the
field may be greater than those treated
in laboratory studies. Researchers
USDA-ARS
workers at Joplin
Site maintain test
plots to which
phosphorous (P)
has been added.
Pb, Zn, and Cd. Pb-bioavailability in the
soils will be measured using the weaning rat
model. For more information, contact Dr. Bill
Berti (DuPont Central Research and
Development) 302-451-9224, or Dr. Jim
Ryan (U.S. EPA/NRMRL), 513-569-7653.
Phytoremediation Team
Sponsors Alternative
Cover Workshop
The Phytoremediation of Organics Action
Team sponsored a September 1997 work-
shop in Cincinnati, OH, to assess field
application of alternatives to conventional
landfill covers, with particular emphasis on
vegetative caps. A vegetative cap is a
long-term, self-sustaining cover of plants
growing in or over materials that pose
environmental risk, which reduces the risk
to an acceptable level and requires mini-
mal maintenance.
The workshop agenda included presenta-
tions and discussions to provide back-
ground and data for use in determining
research needs and priorities. Work group
sessions during the meeting examined a
variety of topics, including alternatives for
infiltration control, erosion control, and
remediation; case histories of applications
of vegetative caps and other non-conven-
tional covers; and ecosystem factors to be
considered in using sustainable covers. In
addition, attendees considered regulatory
issues, data needs, resource require-
ments, and potential sites in defining pri-
orities for further research on alternatives.
A report on the workshop, including
action items and timetables for accom-
plishing them, will be available late in
October on the Phytoremediation Action
Team's page on the RTDF's World Wide
Web site. For additional information, con-
tact Steve Rock (U.S. EPA/NRMRL) at
513-569-7149.
In Situ Flushing Team Holds
Organizational Meeting
The In Situ Flushing Action Team held its
organizational meeting May 8-9,1997, at
Hill Air Force Base (AFB), Utah. Team
co-chairs are Stephen Shoemaker
(DuPont Engineering) and Dr. Lynn Wood
(U.S. EPA's NRMRL). The two-day meet-
ing provided an update on field demon-
strations conducted at Hill AFB of various
in situ flushing techniques, an assess-
ment of the potential applicability of these
technologies for source zone remedia-
tion, and information on barriers to tech-
nology deployment, including uncertain-
ties associated with performance, cost,
and predictability.
Based on this information and other dis-
cussions during the meeting, participants
agreed to focus the team's activities on
achieving the following objectives:
• to design a full-scale demonstration
• to refine technical practices and
develop technical practices
guidance information
• to compare the coststoenefits of
in situ techniques and convention-
al treatments
• to develop and evaluate adjuvant
recovery and reuse systems
• to analyze appropriate technology
performance criteria and end points.
The team is in the process of organizing
subgroups to address these objectives.
The work of the subgroups will be used to
design a generic, large-scale source
remediation system using enhanced in
situ solubilization or mobilization.
A complete summary of the meeting is
available on the In Situ Flushing Action
Team's page on the RTDF site on the
World Wide Web. For more information,
contact Dr. Wood, 405-436-8552, or Mr.
Shoemaker, 713-586-2513.
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1
RTDF Update 4- November 1997
Bioremediation
Demonstrations Continue
Phase I demonstrations of three bioreme-
diation processes—cometabolic biovent-
Ing, accelerated anaerobic biodegradation,
and intrinsic bioremediation—will continue
untS 1998. (See the April 1997 issue of
RTDF Update for a report on interim
results from these demonstrations.) All
three of these demonstrations, sponsored
by the Bioremediation of Chlorinated
Solvents Consortium, are underway at
Dover Air Force Base (AFB) in Dover, DE.
The Bioremediation Consortium has
selected Hill Air Force Base, UT, as the
site for a Phase II demonstration of
cometabolic bioventing, and preparatory
laboratory work using site soil is underway.
Tho Consortium is seeking sites for Phase
II work on intrinsic bioremediation and
accelerated anaerobic biodegradation.
Information about the bioremediation
processes under study and the demon-
strations being conducted at Dover AFB is
available on the Bioremediation
Consortium's page on the RTDF's World
Wide Web site. For additional information,
contact Dr. Gregory Sayles (U.S.
EPA/NRMRL), 513-569-7607, or Dr. David
Ellis (DuPont Specialty Chemicals), 302-
892-7445.
Resources
The following updated fact sheets on the
RTDF and each of its Action Teams will be
available soon from U.S. EPA's National
Center for Environmental Publications and
Information (NCEPI).
Remediation Technologies Development
Forum (EPA 542-F-97-012)
Remediation Technologies Development
Forum: Questions and Answers Fact Sheet
(EPA542-F-97-017)
Lasagna™ Public-Private Partnership
(EPA542-F-97-012a)
Bioremediation of Chlorinated Solvents
Consortium (EPA 542-F-97-012b)
Permeable Reactive Barriers Action
Team (EPA 542-F-97-012c)
IINERT Soil-Metals Action Team (EPA
542-F-97-012d)
In Situ Flushing Action Team (EPA 542-
F-97-013)
Phytoremediation of Organics Action
Team (EPA 542-F-97-014)
Sediments Remediation Action Team
(EPA542-F-97-015)
Printed copies of these publications may
be ordered by contacting NCEPI at 513-
489-8190. Be sure to specify the docu-
ment number shown when ordering.
Copies of the fact sheets also may be
downloaded from the RTDF's World Wide
Web site.
United States
Environmental Protection Agency
(5102G)
Washington, DC 20460
Official Business
Penalty for Private Use $300
EPA542-F-97-016
October 1997
BULK RATE
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Paid
EPA
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