U.S. Environmental
Protection Agency
Washington, DC 20460
Office of Solid Waste and
Emergency Response
Technology Innovation Office
September 1992
EPA/542/N-92/005
Groundwater Currents
Developments in innovative groundwater treatment
Why We Are Here
By Walter W. Kovalick, Jr., Ph.D., Director, Technology Innovation Office
' elcome to our venture to im-
prove upon the availability of new
information on the development
and demonstration of innovative
groundwater remediation tech-
niques. Groundwater Currents will
have a broader focus than its com-
panion publication, Tech Trends.
Not only will we report on innova-
tive in situ and ex situ groundwater
remediation technologies that are
ready to be applied in the field
(similar to the applied focus of
Tech Trends), but also on research
that is not as far along the de
velopment chain, such as
emerging technologies and
other research still in the hop
per. In addition, you will see
articles on innovative monitor-
ing technologies and analysis
systems, references to new
regulations that impact
groundwater remediation, de-
scriptions of data bases that
capture who is doing what in in-
novative treatment and how to
access them, highlights on cur-
rent issues such as dense
nonaqueous phase liquids
(DNAPLs) and information on
conferences and publications.
Groundwater Currents will appear
approximately four times a year.
One of our feature articles
in this issue ("Dialogue Begins
in Dallas," page 3) recaps the
results of a facilitated meeting
among stakeholders in
groundwater remediation
researchers, developers,
consultants, the regulated
community and State and
Federal project managers.
The Workshop to Identify Barriers
to In Situ Groundwater Reme-
diation was held on June 24-25,
1992, in Dallas. Among the
needs identified at this
meeting were improved
information exchange forums.
Initial responses to that need
appear in the "FYI" column
on page 2 that describes the
(See Why, page 3)
PILOT RESULTS
Hydraulic Fracturing Enhances In Situ Remediation
By Wendy Davis-Hoover, Risk Reduction Engineering Laboratory
H
lydraulic fracturing shows
great promise for improving
dramatically the effectiveness of a
variety of in situ remediation
techniques for groundwater, soils
and subsurface. Hydraulic
fracturing has long been used to
increase production rates of oil
wells. While it is of little utility as
a remediation technique by itself,
EPA researchers are finding that
fractured wells increase both the
flow rate and the radius of
influence at wells utilizing vapor
extraction, bioremediation,
steam stripping, soil washing and
other remediation techniques.
The fracturing is created
when fluid is pumped down a
borehole until a critical
pressure is reached that
fractures the soil. Sand-laden
slurry is then pumped into the
fracture to create a highly
permeable pathway that
enhances delivery of the
remediation medium (ie.,
steam, biodegradation
organisms) and subsequent
recovery. The EPA research
began in the laboratory in
1988 with soils contained in
biaxial cells. This type of over-
consolidated soil, often
associated with clayey glacial
deposits of low permeability, is
notoriously difficult to remedy
with conventional in situ
technologies. Now, over 100
hydraulic fractures have been
created in glacial drift at six
different sites. Many of the
fractures have been excavated
for the purpose of determining
(See Fracturing, page 4)
This Month in Currents
Hydraulic Fracturing
Groundwater Research Inventory
Special Interest Croup for Croundwater
Groundwater Workshop Identifies Barriers
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POINTS OF INTEREST
In Situ Groundwater Treatment Research and
Demos Inventoried
By Rich Steimle, Technology Innovation Office
pproximately 75% of the
sites on the National Priorities
List have groundwater
contamination. An analysis of
the Records of Decision for
these sites shows that pump
and-treat is chosen almost
exclusively as the remediation
technology. Additionally, the
remediation or control of
contaminated groundwater
using conventional pump-and-
treat technology is difficult at
many sites and, in most cases,
results in inadequate cleanup.
These are some of the findings
of a recent review by the EPA
Technology Innovation Office
(TIO) that looked at ground-
water remediation options.
TIO is seeking public and
private partners to collaborate
in the development and field
application of alternative
treatment technologies for
groundwater remediation.
As a first step toward de-
veloping a promotion strategy,
TIO inventoried alternatives to
pump-and-treat The inven-
tory encompasses chemical,
biological and physical treat-
ment techniques that either
alter the toxicity of the con-
tamination or improve
removal. Specifically, the
study concentrated on in situ
technologies that are in the
research stage, that have been
field tested or that actually
have been demonstrated or
used. TIO s objective is to
help speed the research and
development of groundwater
remediation technology
alternatives. For this first
go-round on the
inventory, TIO concen-
trated primarily on
information from EPA and
EPA-supported groups and
data bases.
TIO found that the
alternatives to pump-and-treat
remediation currently are
extremely limited, with the
exception of oxygen enhance
ment by sparging and hydro-
gen peroxide injection, no
technology has adequate data
from field demonstrations or
actual application to be consid-
ered an alternative at this time.
The research found that only
15 alternative technologies are
in the process of being devel-
oped, and most of them are
still in the bench scale and
pilot stages of research. At the
present rate of development,
these alternate technologies may
not be available for three to five
years However, most of the tech-
nologies are approaching, or are
in, the controlled field experi-
ment stage of development.
In addition to sparging and
hydrogen peroxide injection,
there are 13 other treatment
techniques that are being
researched. These are: nitrate/
acetate enhancement, nitrate
enhancement, bioremediation
with methanotrophic biodegra-
dation, reductive dechlor-
ination, oxygen enhancement
with microbubbles, dehalo-
genation with metal catalysts,
electrokinetics, water or steam
flushing, hydrofracturing,
(See Inventory, page 4)
Log-on to CLU-IN for Groundwater Information
Groundwater Special
Interest Group (SIG) recently
has been added as part of the
EPA electronic bulletin board
for cleanup information, CLU-
IN. The Groundwater SIG
provides a means for pro-
fessionals working in ground-
water remediation to link up
with one another and access
articles and other information
on groundwater issues. We
hope you will take advantage of
the SIG s message exchange to
find and reply to groundwater
technology problems and to
convey new information
quickly to all SIG users. We
particularly invite Federal, State
and private researchers,
technology users, technology
vendors, consultants and site
owners who have a stake in the
development and use of
technology for groundwater
cleanup to use the SIG. We
will keep the SIG stocked with
bulletins on the latest Federal
Register notices, recent EPA
publications and other
information of concern to
groundwater professionals.
Also, please feel free to
upload any information that
you think would be of interest
to other users. If there is
anything in particular that you
would like to see on the SIG,
please leave a message for
TIO s Nancy Dean; if you need
to talk to Nancy in person, she
can be reached at (703) 308-8797.
To log onto CLU-IN and
access the SIG, you need a
computer, a modem, a phone
line and telecommunications
software (such as CrossTalk ,
Procomm or SmartCom ).
Set your communications
parameters to 8 data bits, no
parity and 1 stop bit. The
phone number is (301) 589-
8366. If you have trouble
logging on, either through
your modem or through a
IAN system or data switch,
contact the System Operator
(SYSOP) at (301) 589-8368.
To get a copy of the CLU-IN
User s Manual, you may: down-
load it directly from CLU-IN;
leave a message for the
SYSOP on CLU-IN; or call
the SYSOP.
Groundwater Currents
-------
CONFERENCE HIGHLIGHTS
Dialogue Begins in Dallas
PA s Technology
Innovation Office (TIO)
hosted a forum in Dallas on
June 24-25 at which peers in
the groundwater remediation
field met to identify barriers
and opportunities for the
development of alternative
groundwater remediation
technologies. About 45
researchers, technology
developers, industry and con-
sulting firms and personnel
from Federal and State
agencies gathered at the
Workshop to Identify Barriers to
In Situ Groundwater
Remediation. To maximize
substantive dialogue by all
participants, the attendees
broke up into three smaller
discussion groups. As each
group later summarized its
discussions for the plenary
session, it was apparent that
the issues were similar from
group to group.
Stringent cleanup stan-
dards were named as a major
factor limiting the develop
ment and use of innovative
technologies, because inno-
vative technologies may not
meet those standards. Reg-
ulations are perceived as mak-
ing it too difficult for a party
responsible for cleanup to run
pilot tests to determine the
effectiveness of an innovative
technology for a particular site,
without incurring penalties if
the test results indicate that the
technology is not effective
enough. Another variable
that hampers decisions to try
innovative in situ treatment
technologies is the lack of
cost and performance data
to compare to pump-and-
treat costs and performance.
The groups concurred that
decisions typically are made
that choose traditional
pumpand-treat methods in
lieu of more innovative tech-
nologies, even though it is
known that pumpand-treat
remediation will not meet
cleanup standards.
The groups focused on
potential solutions to break
down barriers that currently
hinder the development and
use of innovative ground-
water remediation tech-
nologies. Solutions centered
around the need to improve
the current state of ground-
water remediation through
research and demonstra-
tions, and the need for a
stronger and broader infor-
mation network. Moving
research into the marketplace
was seen as tied to both formal
demonstration programs and
information transfer.
To improve the state of
groundwater remediation,
panelists envision a two
pronged approach a com-
bination of existing institu-
tions and bold new steps.
Some panelists suggested:
more EPA Superfund Inno-
vative Technology Evaluation
(SITE) demonstrations for
groundwater; risk-sharing be-
tween the government and
private industry; and a special
groundwater remediation re-
search site, such as the
Borden site in Canada, to
field test in situ innovative
treatment technologies.
Panelists vocalized a
clear need to generate and
more widely distribute infor-
mation on innovative
groundwater remediation
developments, information
on the potential savings re-
lated to lower operation and
maintenance costs, and data
on performance of the in situ
technologies in relation to in-
tensive longer-term pump
and treat methods. In addi-
tion to continuing EPA s vid-
eos, technical support
papers, fact sheets and elec-
tronic bulletin board systems,
panelists suggested making
third-party technology evalu-
ations available and publish-
ing a journal to synthesize
information. Information
should be transferred to
State and local regulators, in
addition to the current audi-
ence of researchers, develop
ers and cleanup parties and
personnel, so that these State
and local decisionmakers can
become more aware of ad-
vantages of the alternatives to
pumpand-treat.
The discussions at Dallas
were productive. TIO plans
to incorporate the Workshop
proceedings, along with in-
put from EPA Regional, labo-
ratory and headquarters staff,
State program staff and Fed-
eral facilities staff, to produce
a broader strategy for increas-
ing the development and
use of innovative treatment
technologies for groundwa-
ter remediation.
For more information,
or a copy of the workshop
proceedings, please contact
TIO s Rich Steimle at 703-
308-8846 or Nancy Dean at
703-308-8797. A
Why (from page 1)
new Groundwater Special
Interest Group network that
you can access on the CLU-IN
Electronic Bulletin Board. We
also are including an article
on a recent inventory of
groundwater research that
focuses on the status of in
situ research at EPA and by
EPA-supported groups.
In addition to the infor-
mation we uncover, we would
like to hear from you. Let us
know when you have new
developments that we could
pass on to your colleagues in
the groundwater remediation
arena, or when you would
like us to address a question
or an issue. Please address
correspondence to >
Editor,
Groundwater Currents
Technology Innovation
Office (OS-HOW)
Office of Solid Waste and
Emergency Response
U.S. EPA
401 M Street, S.W.
Washington, DC 20460
Groundwater Currents
-------
Fracturing (from page 1)
geometric parameters such as
thickness, diameter, shape and
orientation. Data from the
excavations and sites surfaces
have been entered into a data
base that enables one to
design the depth, desired
shape, etc., of fractures to tailor
them to site conditions.
During the past year,
fractured wells (with non-
fractured conventional wells as
controls) were installed at
EPA s Center Hill field site in
silty-clay tills of low permeability
in order to test the flow rate
and the radius of influence of
groundwater vapor extraction
wells. Flow rates at the fractured
wells increased up to tenfold
5 cubic feet per minute (CFM)
in the fractured wells compared
to only 0.5 CFM in the control
well, depending on weather
conditions (precipitation de-
creased flow rates until the water
was removed from the wells).
Groundwater bioremed-
iation is receiving special con-
sideration in a sister project
where EPA is developing a
solid compound that slowly
releases oxygen, with slowly
dissolving granulated nutrients,
to fill the fractures at a site
seeded with a surrogate
contaminate of propylene
glycol. EPA is also testing the
effectiveness of hydraulic
fractures with vapor extraction
and bioremediation in
contaminated soil.
The current technology
allows for the creation of
horizontal fractures from
vertical wells. EPA is currently
researching other drilling
techniques for the installation
of horizontal wells to enable
access to areas under buildings,
tanks and other structures
where conventional drilling
techniques are not feasible.
For more information, call
Wendy Davis-Hoover at EPA s
Risk Reduction Engineering
Laboratory at 513-569-7206. A
Inventory (from page 2)
surfactant mobilization,
alteration of chemical con-
ditions, pneumatic fracturing
and solvent mobilization.
Only two recovery tech-
nologies are specifically
designed to solubilize or
mobilize inorganic compounds.
However, approximately 20% of
Superfund sites have ground-
water contaminated by lead,
arsenic or chromium.
Another conclusion from
the inventory is that the success
of a remediation technology is
contingent on its compatibility
with the delivery system. The
systems for delivering in situ
treatment to contaminated
groundwater are complicated
and underdeveloped. While
some researchers are devel-
oping necessary new delivery
systems, others are relying on
existing delivery systems such as
injection or trench infiltration.
The results of the inventory
pint toward the need to
develop a strategy to orient
research toward more in situ
groundwater treatment
research and demonstration.
In addition to EPA
research, TIO is working with
other Federal agencies to
evaluate the activities in their
demonstration programs to
further support in situ
groundwater technologies.
For more information on
the Inventory, call TIO s Rich
Steimle at 703-308-8846.A
Conference Alert
The fourth Forum or»
Innovative Hazardous
Waste Treatment
Technologies: Domestic
and International
will be held in
San Francisco, California,
on November 17-19,
1992.
Call (800) 783-3870 for
registration information.
To order additional copies of Groundwater Currents, or to be included on the permanent mailing list, send a fax request to the
EPA Publications and Information Center (EPIC) at 513-891-6685, or send a mail request to EPIC, 11029 Kenwood Road,
Building 5, Cincinnati, OH 45242. Please refer to the document number on the cover of the issue if available.
Groundwater Currents welcomes readers' comments and contributions. Address correspondence to:
Managing Editor, Groundwater Currents (OS-110W), U.S. Environmental Protection Agency,
401 M Street S.W., Washington, DC 20460.
United States
Environmental Protection Agency
Office of Solid Waste and Emergency Response
Technology Innovation Office (OS-110W)
Washington, DC 20460
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