United States
Environmental Protection
Agency
Robert S. Kerr Environmental
Research Laboratory
Ada, OK 74820
Research and Development
EPA/600/S2-84/182 May 1985
Project Summary
State-of-the-Art of Aquifer
Restoration
Robert C. Knox, L. W. Canter, D. F. Kincannon, E. L. Stover, and C. H. Ward
This two-volume report presents a
summary of the state-of-the-art of
aquifer restoration. Included are eight
sections and seven appendices. The
text includes sections on: (1) ground
water pollution control through in-
stitutional measures, source control,
stabilization/solidification methods,
well systems, interceptor systems,
capping and liners, sheet piling,
grouting and slurry walls; (2) treat-
ment of ground water via air strip-
ping, carbon adsorption, biological
treatment, chemical precipitation, and
other treatment techniques; (3) in-sltu
chemical treatment and biological
stabilization; (4) a protocol for aquifer
restoration decision-making; and (5)
techniques for aiding the decision-
making process. The appendices (Vol-
ume II) include: (1) case studies of
aquifer restoration; (2) considerations
regarding an aquifer restoration infor-
mation center; (3) information for
public participation in aquifer restora-
tion decision-making; and (4) an an-
notated bibliography of 225 selected
references. The state-of-the-art of
aquifer restoration is a rapidly chang-
ing technology, with many instances
of single or combined techniques
either planned or recently imple-
mented. Unfortunately, few if any ef-
forts have yet been completed. Thus,
effectiveness, duration and cost data
are as yet incomplete. A major need
exists for a systematic and
comprehensive study of the cost-
effectiveness of aquifer restoration
technologies.
This Project Summary was devel-
oped by EPA's Robert S. Kerr En-
vironmental Research Laboratory,
Ada, OK, to announce key findings of
the research project that is fully
documented in a separate report of
the same title (see Project Report
ordering information at back).
Introduction
As recently as the late 1970s, the four
most common perceptions of aquifer
restoration measures were: (1) they were
costly; (2) they were time-consuming; (3)
they were not always effective; and 14)
pertinent information was unavailable.
Although these perceptions have not been
totally overcome, the state-of-the-art is
progressing significantly. An ever-
increasing amount of information has
become available concerning aquifer
restoration and ground-water cleanup.
Much of this new information has been
presented in a variety of conferences and
symposia. However, the amount of infor-
mation published in the refereed literature
remains sparse and a significant amount
of information also remains unavailable
because it is associated with litigation.
The final report presents the available in-
formation as it relates to technologies
dealing with ground-water pollution. Also
included is the most recent information on
mobile wastewater treatment technologies
and in-situ treatment of contaminated
ground water. From a thorough analysis
of this information, a protocol (structured
approach) for selecting remedial actions
has been developed. An accompanying
volume of seven appendices to the final
report provides information on case
studies and public participation in
decision-making; and an annotated
bibliography of 225 selected references.
Ground-Water Pollution
Pollution of ground water can result
from many activities, including leaching
from municipal and chemical landfills and
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abandoned dump sites, accidental spills of
chemicals or waste materials, improper
underground injection of liquid wastes,
and placement of septic tank systems in
hydrologically and geologically unsuitable
locations. In recent years, aquifer pollu-
tion from man's waste disposal activities
have been documented with increasing
frequency. Concurrently, demands for
usage of ground water have been increas-
ing due to population growth and dimin-
ishing opportunities for economical
development of surface water supplies.
Until recently, many ground-water profes-
sionals and policy-makers generally held
that pollution of an aquifer severely cur-
tailed or even eliminated its use. Recently,
however, this view has changed as a
result of increasing demands for ground
water, the development of appropriate
methodologies for aquifer cleanup, and
encouraging progress with systems now
on line. The focus on methodologies has
been heightened by current hazardous
waste site cleanup efforts financed by
"Superfund" state and industrial monies.
Classification of Methodologies
Table 1 lists aquifer cleanup meth-
odologies organized by acute or chronic
pollution problems. Acute pollution of an
aquifer may result from inadvertent spills
of chemicals or releases of undesirable
materials and chemicals, usually as a
result of a transportation* accident. Such
unplanned pollution events often require
an emergency response. Chronic aquifer
pollution comes from numerous point and
area sources and involves conventional
pollutants such as nitrates and bacteria,
or more toxic compounds such as gaso-
line, metals, and synthetic organic
chemicals.
Methodologies for aquifer cleanup
can also be characterized in terms of
the goals of abatement and restora-
tion. Abatement refers to the applica-
tion of methodologies which prevent
or minimize pollutant movement into
ground water, or prevent contami-
nated plume migration into usable
aquifer horizons (the latter example is
also called plume management). Aqui-
fer restoration refers to the restor-
ation of water quality to background
quality, usually by removing both the
source(s) of pollution and renovating
the polluted portion of the aquifer. If the
pollution source(s) has already been
dissipated by time, restoration may in-
volve only renovation of the polluted
ground water.
Table 1. Methodologies for Aquifer Cleanup
Goal
Pollution
Problem
Methodologies
Acute
Abatement 1. In-situ chemical fixation.
2. Excavation of contaminated soil with subsequent backfilling with
"clean" soil.
Restoration 1. Remove? wells, treatment of contaminated ground water, and
recharge.
2. Removal wells, treatment of contaminated ground water, and
discharge to surface drainage.
3. Removal wells and discharge to surface drainage.
Chronic Abatement 1. In-situ chemical fixation.
2. Excavation of contaminated soil with subsequent backfilling with
"clean" soil.
3. Interceptor trenches to collect polluted water as it moves laterally
away from site.
4. Surface capping with impermeable material to inhibit infiltration of
leachate-producing precipitation.
5. Subsurface barriers of impermeable materials to restrict hydraulic
flow from sources.
6. Modify pumping patterns at existing wells.
7. Inject fresh water in a series of wells placed around source or con-
taminant plume to develop pressure ridge to restrict movement of
pollutants.
Chronic Restoration 1. Removal wells, treatment of contaminated ground water, and
recharge.
2. Removal wells, treatment of contaminated ground water, and
discharge to surface drainage.
3. Removal wells and discharge to surface drainage.
4. In-situ chemical treatment.
5. In-situ biological treatment.
'Could also be referred to as interceptor wells.
It should be noted that a given aquifer
cleanup project may involve usage of
several methodologies in combination. For
example, in an acute situation, excavation
and backfilling might be used in conjunc-
tion with removal wells, treatment of con-
taminated ground water, and discharge to
surface drainage. A chronic pollution
cleanup project may include surface cap-
ping, subsurface barriers, and in-situ
chemical treatment.
State-of-the-Art
Many different measures, ranging from
institutional mandates to physical tech-
nologies, have been proposed for the pro-
tection and/or cleanup of degraded
ground water. Institutional measures
already implemented consist mainly of
legislated authority to enforce cleanup
mandates. In addition, a number of states
have developd preventive policies such as
requiring liners and/or surface water con-
trol at waste disposal facilities. A number
of Federal institutional measures, in-
cluding the Comprehensive Environmental
Response, Compensation and Liability Act
(Superfund), the Safe Drinking Water
Act, and the Underground Injection Con-
trol Program, have provisions for address-
ing the protection or cleanup of ground
water.
The large number of physical tech-
nologies useful for the cleanup of polluted
ground water come from several inter-
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related disciplines. The traditional
hydrogeologic technology of pumping
wells has been complemented by tech-
nologies from civil engineering and con-
struction fields, such as grouting and
slurry walls; and from the agricultural in-
dustry with its subsurface drainage tech-
niques. At any one she, the remedial pro-
gram employed often consists of a com-
bination of hydrogeologic and engineering
technologies. Not all of these possible
combinations have been tried and proven
for ground water applications because
performance data for many of them are
just now becoming available. Table 2 lists
some of the advantages and disadvan-
tages of the various physical measures
available for addressing ground water
remediation problems.
Despite the innovative technologies
now being promoted, the most popular
ground water cleanup measure remains
removal and treatment. The mechanics of
ground water flow to wells is well known
and readily applied. Most often such
knowledge is combined with traditional
wastewater treatment technologies to
treat a polluted aquifer. In fact, this
cleanup technique has been applied so
often that there is increased interest and
study toward developing compact, mobile
wastewater treatment units; especially
units for removal of synthetic organics by
adsorption or by air stripping.
Treatment of polluted ground water by
in-situ techniques is still relatively new;
however, such treatment is receiving in-
creased research attention. Successful in-
site treatment is highly dependent on both
the characteristics of the pollutant(s) and
the subsurface hydrogeology. Although
case studies with adequate controls to
determine effectiveness of in-situ tech-
niques are limited, it is generally recog-
nized that in-situ techniques will be ap-
plicable only to sites meeting very specific
requirements. Examples of in-situ tech-
nologies include in-situ chemical treat-
ment and in-situ biological stabilization
through enhancement of the indigenous
microbial population or addition of accli-
mated microorganisms.
The costs of aquifer restoration meas-
ures are dependent on a variety of fac-
tors. Published information concerning
cost of remedial techniques has most
often been reported as unit cost data or
Table 2. Advantages and Disadvantages of Physical Aquifer Restoration Technologies
Technology Advantages
Disadvantages
Source Control Strategies
Well Systems
Interceptor Systems
1. Reduces the threat to the ground-water en-
vironment.
2. Accelerates the time for "stabilization" of
waste disposal facilities.
3. Offers opportunities for economic recovery.
1. Efficient and effective means of assuring
ground-water pollution control.
2. Can be installed readily.
3. Previously installed monitoring wells can
sometimes be employed as part of well
system.
4. Can sometimes include recharge of aquifer
as part of the strategy.
5. High design flexibility.
6. Construction costs can be lower than ar-
tificial barriers.
1. Not only easy but also inexpensive to in-
stall.
2. Useful for intercepting landfill side seepage
and runoff.
3. Useful for collecting leachate in poorly
permeable soils.
4. Large wetted perimeter allows for high rates
of flow.
5. Possible to monitor and recover pollutants.
6. Produces much less fluid to be handled
than well-point systems.
1. Increased capital and maintenance costs.
2. Monitoring and skilled operator re-
quirements.
1. Operation and maintenance costs are high.
2. Require monitoring program after installa-
tion.
3. Withdrawal systems necessarily remove
clean (excess) water along with polluted
water.
4. Some systems may require the use of
sophisticated mathematical models to
evaluate their effectiveness.
5. Withdrawal systems will usually require sur-
face treatment prior to discharge.
6. Application to fine soils is limited.
1. When dissolved constituents are involved, it
may be necessary to monitor ground water
downgradient of the recovery line.
2. Open systems require safety precautions to
prevent fires or explosions.
3. Interceptor trenches are less efficient than
well-point systems.
4. Operation and maintenance costs are high.
5. Not useful for deep disposal sites.
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Table 2. (continued)
Technology
Advantages
Disadvantages
Collector Drains
Surface Water Control, Capping and Liners
a. Natural Attenuation (no liner, no cap)
b. Engineered Liner
c. Engineered Cover
d. Engineered Cover and Liner
1. Operation costs are relatively cheap since
flow to underdrains is by gravity.
2. Provides a means of collecting leachate
without the use of impervious liners.
3. Considerable flexibility is available for design
of underdrains; spacing can be altered to
some extent by adjusting depth or modify-
ing envelope material.
4. Systems are fairly reliable, providing con-
tinuous monitoring is possible.
5. Construction methods are simple.
1. No leachate collection, transport and treat-
ment costs.
2. Reduced construction costs.
1. Lessens hydrogeologic impact.
2. Allows waste to stabilize quickly.
1. Lessens hydrogeologic impact after closure.
2. Reduces construction costs relative to
liners.
1. Lessens environmental impacts.
2. Minimizes post closure leachate collection,
transport and treatment costs.
3. Politically/socially acceptable.
1. Not well suited to poorly permeable soils.
2. In most instances, it is not feasible to
situate underdrains beneath an existing site.
3. System requires continuous and careful
monitoring to assure adequate leachate col-
lection.
1. Requires unusually favorable hydrogeologic
setting.
2. Regulatory acceptance difficult to obtain.
3. Long-term liabilities.
1. "Clay-bowl" effect.
2. Increased construction costs.
3. Chance for surface discharge.
1. Increases closure costs.
2. No leachate control during site operations.
3. Long-term monitoring and land surface
care.
1. High cost for engineering and construction.
2. Need high quality clay or synthetic material.
3. Lengthened time for waste stabilization.
Sheet-Piles
Grouting
1. Construction is not difficult; no excavation
is necessary.
2. Contractors, equipment, and materials are
available throughout the United States.
3. Construction can be economical.
4. No maintenance required after construction.
5. Steel can be coated for protection from cor-
rosion to extend its service life.
1. When designed on basis of thorough
preliminary investigations, grouts can be
very successful.
1. The steel sheet piling initially is not water-
tight.
2. Driving piles through ground containing
boulders is difficult.
3. Certain chemicals may attack the steel.
1. Grouting is limited, to granular types of soils
having a pore size large enough to accept
grout fluids under pressure, yet small
enough to prevent significant pollutant
migration before implementation of grout
program.
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Table 2.
(continued)
Technology
Advantages
Disadvantages
S furry Walls
2. Grouts have been used for over 100 years in
construction and soil stabilization projects.
3. Many kinds of grout to suit a wide range of
soil types are available.
1. Construction methods are simple.
2. Adjacent areas are not affected by ground-
water drawdown.
3. Bentonite (mineralI will not deteriorate with
age.
4. Leachate-resistant bentonites are available.
5. Low maintenance requirements.
6. Eliminate risks due to strikes, pump
breakdowns, or power failures.
7. Eliminate headers and other above ground
obstructions.
2. Grouting in a highly layered soil profile may
result in incomplete formation of a grout
envelope.
3. Presence of high water table and rapidly
flowing ground-water limits groutability
through;
a. extensive transport of contaminants.
b. rapid dilution of grouts.
4. Some grouting techniques are proprietary.
5. Procedure requires careful planning and
pretesting. Methods of ensuring that all
voids in the waff have been effectively
grouted are not readily available.
6. Grouts may not withstand attack from
specific pollutants.
1. High cost of shipping bentonite from the
west.
2. Some construction procedures are patented
and require a license.
3. In rocky ground, overexcavation is
necessary because of boulders.
4. Bentonite deteriorates when exposed to
high ionic strength leachates.
5. Adequate key to impermeable formation is
critical.
6. Methods for assessing in-place integrity not
available.
national average costs. However, from
study of the few specific reports on
economics and consideration of several
case studies, one significant conclusion
can be drawn: the cost of restoring an
aquifer will not always be in the tens of
millions of dollars; a more reasonable
range might be from several hundred
thousand dollars to several million dollars.
Not all aquifer restoration projects will fall
under the Superfund category which has
received so much publicity. In fact, ex-
amples of successful and economic aqui-
fer cleanup projects using private funds
are not uncommon. For example, in New
Jersey more than three dozen restoration
programs representing more than $30
million in private funds are underway.
Development of feasible strategies (al-
ternatives) from potential aquifer restora-
tion measures also depends on many fac-
ors. In developing a set of alternatives, it
is necessary to consider the total system
and to include future preventive measures
in addition to current cleanup activities.
Because ground-water pollution is not
solely a hydrogeologic problem, proposed
solutions demand a multi-disciplinary ap-
proach. A comprehensive preliminary
study is necessary to organize existing
data and eliminate duplication of effort;
such a study also will prevent premature
implementation of poorly designed alter-
natives prone to failure. The development
of a list of alternative remedial measures,
following the preliminary study, should be
based on an iterative process. By iterating
through the selection process, measures
can be refined and selected in order to
minimize design flaws which often go un-
detected in the subsurface environment.
'Selection of a single aquifer restoration
strategy from a list of alternative
measures requires careful and prudent
consideration of the economic, en-
vironmental and public health (risk) im-
plications of each alternative. In eval-
uating the economics of a remedial meas-
ure, it is important to include all costs and
to relate them to a common time period.
Environmental evaluations should recog-
nize any irretrievable commitments of the
subsurface environment, and the finite life
of some measures such as liners. Risk
assessment is a new field of study and as
such, there are few available risk models
and a dearth of risk data.
A myriad of techniques are available for
aiding decision-making; these are based
on a balanced and systematic considera-
tion of the economic, environmental and
risk features inherent in feasible alter-
natives. Any technique used should in-
clude public participation as an integral
component. Because of adverse publicity
given such sites as Love Canal, Valley of
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the Drums, and Times Beach, the public
has become extremely concerned about
sites with the potential for contaminating
their drinking (ground) water supplies. A
number of procedures for incorporating
public input into the decision-making pro-
cess are available.
Protocol for Aquifer
Restoration Decision-Making
The general approach for developing
aquifer restoration strategies and selecting
the most appropriate one for meeting a
given need is, for the most part, intuitive-
ly obvious. A logical first step is a
preliminary assessment of the nature of
the problem. Based on the preliminary
assessment, a number of alternative
strategies (remedial measures) can be
developed. From the list of possible alter-
natives, an optimum choice is selected by
systematically considering a series of deci-
sion factors, environmental impacts and
cost-effectiveness analyses. Implementa-
tion and construction of the chosen alter-
native then follows, accompanied by a
monitoring program.
Another objective of this study was to
design a structured protocol that could be
followed for developing aquifer restoration
strategies. Figure 1 is a flowchart repre-
sentation of the procedure herein devel-
oped based on analysis of the available
literature. Emphasis is placed on the ac-
tual procedure for developing a list of
technical alternatives based on approp-
riate consideration of numerous decision
factors. The procedure is not intended to
be a set of explicit instructions; rather it is
a generalized approach which, when
modified, could be applied to a wide array
of ground water quality problems.
Recommendations
Based upon this study of the state-of-
the-art of aquifer restoration, seven
recommendations are presented:
(1) Systematic Research Program —
There is a need for development of
a systematic research program
aimed at increased understanding of
the behavior and effectiveness of
various remedial measures. Outlined
in Table 3 is an example list of
research needs concerning aquifer
restoration measures.
(2) Aquifer Restoration Information
Center — Currently, information
directly related to ground-water
quality control and cleanup is being
generated from a large number of
widely dispersed activities. Addi-
tionally, extant and informative
Selection of
Multi-Disciplinary
Team
Problem Definition
and Characterization
Preliminary Study
Plume Delineation
Hydrogeologic Characterization
Site Characterization
Water Use and Requirements
Human Health Costs/Rish Assessment
Land Use Patterns/Growth Projections
Regulations/Institutional Constraints
Funding
Evaluate Data
4
Identify Data Needs
Goal Identification Matrix
Preliminary Feasible Alternatives
I
Preliminary Screening
I
(Iteration) •+ — Scope Design — >»• Feasible Alternatives
r Matrix
r
Development
of
Alternatives
\
Economic t
Environment
Ft i sit Ass
I
\
Decision-Makir
'
Evaluation
il Evaluation
sssment
r
ig Techniques
Evaluation
of
Alternatives
Selection of
Aquifer Restoration
Strategy
Selective Alternative
Figure 1. Flowchart for aquifer restoration decision-making.
Table 3: Examples of Aquifer Restoration Research Needs
Topical Area Specific Needs
Surface Capping and Liners
Slurry Walls
1. Development of standardized tests for assessment of in-place
integrity.
2. Development of accelerated testing procedures for assessing
the long-term performance of liners and seals.
3. Effects of root-penetration on surface caps.
}. Effects of organics on bentonite—change in bentonite pro-
perties and migration of organics through bentonite over
time.
2. Effects of organics on various bentonite-cement mix-
tures—change in properties of mixtures (e.g., shrink/swell
potential) and migration of organics through the mixtures
over time.
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Table 3. (continued)
Topical Area
Specific Needs
Air Stripping of Volatile
Organics from Ground Water
Removal of Organics via Ac-
tivated Carbon Treatment
3. Development of techniques for assessing the in-place integri-
ty of slurry walls {permeability, bottom connections, seepage,
etc.).
1. Stripping of single compounds vs. mixtures of compounds.
2. Stripping characteristics of different classes of volatile
organics.
3. Direct or indirect I fouling of packing media) interferences of
ground-water constituents on stripping. Examples include
metals (Fe, Mn, Cr), inorganic salts (TDS), % saturation of
oxygen, non-volatile organics, and microbial activity.
4. Effectiveness of batch vs. continuous vs. combination (batch
and continuous) stripping.
5. Effectiveness of natural desorption vs. mechanical stirring.
6. Use of Total Organic Carbon (TOO and COD as surrogate in-
dicators of volatile organics.
7. Effects of concentrations of volatile organics on stripping effi-
ciency and effectiveness.
8. Use of simulated vs. actual ground water for treatability
studies.
9. Optimization of packed tower design in terms of packing type
and size, detention time, air/water ratio, height of packing,
temperature and variations, moving gas (air, oxygen, ozone),
stripping enhancement via chemical additions, counter-
current vs. cross-current vs. co-current flow, no packing,
single tower vs. towers in series, scale-up from laboratory
studies to pilot plants to full design, and development of
computer-based design program.
10. Atmospheric dispersion of released organics, and other issues
related to air pollution.
11. Cost-effectiveness of existing facilities.
1. Adsorption of single compounds vs. mixtures of compounds.
2. Adsorption characteristics of different classes of compounds.
3. Direct or indirect (fouling of activated carbon) interferences
of ground water constituents on adsorption. Examples in-
clude: metals (Fe, Mn, Cr), inorganic salts (TDS), % satura-
tion of oxygen, non-volatile organics, and microbial activity.
4. Use of TOC and COD as surrogate indicators of adsorbable
organics.
5. Effects of concentrations of adsorbable organics on adsorp-
tion.
6. Use of simulated vs. actual ground water for treatability
studies.
7. Optimization of activated carbon column design in terms of:
size of carbon, detention time, column diameter, depth of
carbon, temperature and variations, adsorption enhancement
via chemical additions, single column vs. columns in series,
scale-up from laboratory studies to pilot plants to full design,
and development of computer-based design program.
8. Cost-effectiveness studies of existing facilities.
material can be found in sources
somewhat related but not directly
applied to ground water. An aquifer
restoration information center is
needed to collect available and per-
tinent information. The centralized
information could be categorized
according to sources, pollutants,
remedial measures employed, costs,
and effectiveness. The centralized
and categorized information could
be disseminated much more effi-
ciently.
In addition to information on
cases of ground-water pollution
cleanup there is a need for cat-
aloging the growing number of pro-
fessionals and/or companies pro-
viding services related to ground-
water quality management.
In addition to national con-
ferences and symposia, intensive
short courses or workshops devoted
solely to the technical aspects of
aquifer restoration should be
developed.
(3) Monitoring — One aspect of
remedial measure design also
receiving increased interest is
ground-water quality monitoring.
Most remedial measures are design-
ed, at least in part, on the basis of
pre-existing monitoring data. All
remedial measures should include,
as an integral component of their
design, provisions for monitoring
the long-term effectiveness of the
measures employed.
(4) Costs — The costs of remedial
measures is an area severely lacking
in comprehensive and transferrable
information. Information on the
over-all cost-effectiveness of
remedial measures, including the
long-term operation, maintenance
and monitoring costs, is desperately
needed. Research efforts based on
a case study approach should be
conducted to develop cost-effective
information and a data base ap-
plicable to private and publically-
funded cleanups.
(5) Remedial Measure Selection — All
future remedial measures should be
designed and selected based on the
application of a structured decision-
making methodology or protocol.
The methodology should include
provisions for public participation.
The approach utilized must be doc-
umented and technically defensible.
Progress in the field of remedial
measure design and selection can-
t, US OCVERNHENT PRINTING OFFICE 1965 - 559-111/10839
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not proceed based only on an anal-
ysis of previous cases developed by
ad hoc procedures.
(6) Risk Assessment Methodologies —
There is a need for development of
risk assessment methodologies that
can aid in evaluating the need for
and effectiveness of cleanup meas-
ures. Additionally, methodologies
need to be developed that are sim-
ple in theory, easy to apply, and
utilize available data. Methodologies
involving complex stochastic anal-
ysis usually require data that is not
available. The utility of the results
from these methodologies is
minimal.
(7) Product Recovery — Future re-
medial action design should be re-
quired to explore the possibility of
recovering and utilizing the ground-
water pollutants. This has been
widely practiced in cases involving
hydrocarbon leakage from storage
tanks. There may exist other in-
stances in which the pollutants may
be economically recovered, especial-
ly those involving solvent spills.
Recovery and utilization of the pol-
lutants would help to defray costs
of remedial measures.
ft. C. Knox, L W. Canter. D. J. Kincannon, E. L. Stover, and C. H. Ward are with
National Center for Ground Water Research. University of Oklahoma, Norman,
OK 73019.
Jamas F. McNabb is the EPA Project Officer (see below).
The complete report consists of two volumes:
"State-of-the-Art Aquifer Restoration: Volume I. Sections I thru VIII," (Order
No. PB 85-181 071/AS; Cost: $29.50, subject to change).
"State-of-the-Art Aquifer Restoration: Volume II. Appendices A thru G," (Order
No. PB 85-181 089/AS; Cost: $31.00, subject to change).
The above reports will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Robert S. Kerr Environmental Research Laboratory
U.S. Environmental Protection Agency
Ada, OK 74820
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
OCOC329 FS
U S ENVIR PROTECTION AGENCY
REGION 5 LIBRARY
Z30 S OEARBCRN STREET
CHICAGO IL 60404
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