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If LNAPLs and DNAPLs are not removed, they The current recognition of the limitations of pump-
serve as on-going sources of contamination. and-treat technology has led to EPA interest in
However, DNAPLs can be extremely difficult to improving the efficiency of extraction systems, as well
locate and their migration pathways difficult to as increasing development and application of in situ
determine. If present, current application of pump- treatment technologies. The Technology Innovation
and-treat systems may not achieve projected clean- Office (TIO) conducted a study inventorying research,
up goals or meet anticipat-
ed remediation schedules.
Where the above cases
do not exist, current use
of pump-and-treat tech-
nology can be effective
in reducing contamin-
ant levels to the remed-
ial objectives. It also can
be highly effective in con-
taining contamination.
Occurrence of Contaminated Ground
Water at NPL Sites *
Sites with no ground-
water contamination
Sites with ground-
water contamination
(other media ato
contaminated)
* NPL Characterization Project, EPA/640/841/069, November 1991
laboratory studies, and field
demonstrations of in situ
treatment for contaminated
ground water. The study
concluded that there are large
gaps in both in situ technologies
available for ground-water
remediation and research in
developing and evaluating new in
situ treatment technologies for
ground water.
RESEARCH AND DEVELOPMENT
Coal
Higher priority for research and development of in
situ ground-water treatment technologies is needed
to produce new technologies that will be more
effective and achieve cleanup faster than current
technologies.
Synopses of Findings
A current inventory shows that only 15 technologies
to supplement or improve pump-and-treat remedia-
tion are in the research and development stage.
Most of these technologies have entered, or are
ready to enter, the "controlled field experiment"
stage of development. Field studies provide the
quantitative information that is needed to move the
technologies forward to full-scale demonstrations
and eventual applications.
In situ systems require an in-depth understanding of
the subsurface not required with ex situ systems. Site
characterization for a field experiment or demon-
stration of an in situ technology must be comprehen-
sive, but even thorough characterization of a con-
taminated site produces contaminant mass estima-
tions with wide error margins. Without accurate
knowledge of the contaminant mass in the aqui-
fer, it is difficult to determine the effectiveness of
a technology.
Because of these limitations, experimental sites
where contaminants may be introduced are needed
to determine a technology's effectiveness.
Sites with existing contamination, where researchers
can participate in site characterization, are also
needed to demonstrate in situ technologies.
In addition, there is no central repository where
research information is stored. Users are not aware
of technology development and researchers are
not aware of gaps that exist in current research.
Strategic Objectives
Q Investigate the availability of field research sites,
similar to the Borden Canadian Forces Base,
where contaminants may be introduced.
Q Increase the number of demonstrations of in situ
treatment technologies for ground water on
existing waste sites.
Q Prioritize research needs.
Q Improve communication
between technology users
and researchers.
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REGULATIONS
Goal
To reduce barriers to research, development, and
application, State and Federal regulations that are
identified as impediments need to be examined.
Synopses of Findings
Workshop participants identified State and Federal
regulations as impediments including: 1) regula-
tions that do not allow reinjection; 2) enforce-
ment of water quality standards, which serve as
barriers to injection of substances (such as ni-
trates) that could augment in situ bioremedi-
ation; 3) "No Degradation" policies, which may
not allow for the use of Alternate Concentra-
tion Limits (ACLs) for ground-water cleanup;
and 4) the use of Drinking Water Standards
as Applicable or Relevant and Appropriate
Requirements (ARARs) in Superfund.
Strategic Objectives
Q Provide a forum for State and Federal regula-
tors to discuss the evaluation of the injection of
surfactants, co-solvents, nitrates, and other sub-
stances that will assist in cleanup of ground water.
G Provide regulators guidance and protocols in
technical areas of concern, such as hydraulic
control in the area of injection and fate of in-
jected substances.
Q Open a dialogue between concerned parties
about the limitations of current and developing
technologies and achievable cleanup standards.
APPLICATION
Goal
Increase in the selection and use of innovative
treatment technologies for remediation of
contaminated ground water requires incen-
tives for technology users, reduced risk of
failure, and better understanding of the
limitations of existing technology.
Synopses of Findings
A few in situ treatment technologies have been
applied full-scale to ground-water cleanup.
They include in situ bioremediation with
oxygen enhancement by hydrogen peroxide
and air sparging. Application to contaminant
cleanup at sites regulated under other authori-
ties is possible, but, to date, only 12 Superfund
RODs have selected an innovative in situ
technology for ground-water remediation.
There are no incentives to use an innovative
technology because cleanup criteria may not
be met and containment by pump-and-treat
methods would still be needed. Lacking adequate
performance data, Federal and State regulators
are willing to approve long term pump-and-treat
systems to contain the contamination, rather than
apply a new technology that may not meet cleanup
goals. Engineers prefer ex situ systems where
treatment variables, such as temperature, volume,
and duration, can be controlled.
Strategic Objectives
Q Educate stakeholders on in situ ground-water
technologies and the limitations of current
technologies.
Q Collect and standardize cost and performance
data by evaluating full scale applications and
eventually produce design manuals.
Q Reward those who take the risk of using in situ
treatment systems.
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PUMP-AND-TREAT TECHNOLOGY
Coal
The cost and performance of pump-and-treat
technology currently in use must be determined in
order to serve as a benchmark for comparison of
in situ treatment technologies.
Synopses of Findings
For in situ treatment to be routinely considered as
an alternative or enhancement to pump-and-treat,
it must prove to be more effective, less costly, or
more timely in remediating aquifers. However,
there is little published information concerning
the costs and efficiency for current technologies.
Many users are unsure of what the total costs will
be for current pump-and-treat systems and have
no benchmark for comparison against the costs of
alternative technologies.
Strategic Objectives
Q Establish a record of capital, operating, and
maintenance costs for current pump-and-treat
technology use.
Q Determine the actual effectiveness of pump-and-
treat technologies as they are currendy used.
INFORMATION SHARING
Coal
Increase the communication between ground-
water professionals, researchers, regulators, site
managers, and industry by more widely disseminat-
ing concise technology information for in situ
ground-water treatment.
Synopses of Findings
Technology users and regulators have many
questions about new or innovative in situ treat-
ments for ground water. To foster an environ-
ment of acceptance for in situ technology, technol-
ogy users and regulators need information that is
targeted towards resources they use.
Strategic Objectives
Q Track in situ applications of treatment technologies.
Q Improve information distribution to State agencies
and Federal facilities.
Q Encourage innovative technology advocacy in
States, EPA Regions, other Federal agencies, and
professional societies.
Q Assess users' information needs for in situ treat-
ment technologies.
Q Target information sources relied upon by users.
BIBLIOGRAPHY
In Situ Treatment of Contaminated Ground Water: An Inventory ofResearch and Field Demonstrations and Strate-
gies for Improving Ground-Water Remediation Technologies, U.S. EPA, (Available through the Technology
Innovation Office), September, 1992.
Considerations in Ground-Water Remediation at Superjund Sites and RCRA Facilities—Update, Directive 9283.1-06,
U.S. EPA, Office of Solid Waste and Emergency Response (OSWER), May 27,1992.
Evaluation of Ground-Water Extraction Remedies: Phase II, Volume 1, Summary Report, Publication 9355.4-05,
U.S. EPA, Office of Emergency and Remedial Response (OERR), February, 1992.
^
The mission of EPA's Technology Innovation Office (TIO) is to increase government and industry applications of
innovative treatment technologies to contaminated waste sites. To obtain additional information regarding the use of
innovative treatment technologies, contact the Technology Innovation Office (TIO) at (703) 308-8800 or write:
U.S. Environmental Protection Agency, Technology Innovation Office, 401 M Street, S.W. (OS-HOW),
Washington, DC 20460
tftt'^^^
This document is not intended to and does not constitute any rulemaking, policy or guidance by U.S. EPA, and cannot be relied upon to
create substantive or procedural right enforceable by any party.
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