&EPA
United States
Environmental Protection
Agency
Solid Waste and
Emergency Response
(5203G)
Publication 9200.5-223FS
EPA 540/F-95/030
PB95-963315
January 1997
Engineering Forum Issue Paper:
Soil Vapor Extraction Implementation Experiences
Robert Stamnes, PE1 and John Blanchard, PE2
Office of Emergency and Remedial Response
Quick Reference Fact Sheet
This issue paper identifies issues and summarizes experiences with soil vapor extraction (SVE) as a remedy for volatile
organic compounds (VOCs) in soils. The issues presented here reflect discussions with over 30 Remedial Project
Managers (RPMs) and technical experts. This fact sheet has been developed jointly by the the Engineering Forum and
Office of Emergency and Remedial Response, with assistance from the Office of Research and Development. Special
thanks are due to David Becker (USAGE) and Dom DiGiulio (ORD). EPA's Engineering Forum is a group of
professionals, representing EPA Regional Offices, who are committed to identifying and resolving the engineering issues
related to remediation of Superfund and hazardous waste sites. The Forum is sponsored by the Technical Support
Project. The information presented here is advisory in nature, should be verified for its applicability to a given site, and
is not intended to establish Agency policy. RPMs should consult their regional management for appropriateness at their
site before applying the recommendations in this paper.
Soil vapor extraction (SVE) is a commonly used technology for VOCs in soils that EPA has selected as a "presumptive
remedy" (see bibliography at the end of this paper). SVE is an in situ treatment technology that uses vacuum blowers
and extraction wells to strip volatile compounds from unsaturated soil. The extracted vapors are treated at the surface
and released to the atmosphere or reinjected into the subsurface. The extraction wells typically are constructed of
polyvinyl chloride (PVC) pipe, which is screened through the area of contamination. Emissions from the SVE process
often are filtered by activated carbon, or treated either by thermal destruction or condensation refrigeration, before being
released into the air. Consult the bibliography at the end of this fact sheet for additional details.
Index
Site Characterization 1
Determination of Cleanup Levels 2
Riot Testing 2
System Design 3
System Enhancements 4
Implementation and Air Emissions Control 4
Monitoring Extracted Vapor 5
Overall Performance of SVE System 6
Shutting Down the SVE System 6
Community Involvement 7
Bibliography 8
Site Characterization
Before remedial technologies for soil treatment can
be evaluated, a site investigation should be con-
ducted to characterize the soils and other site
features.
Two major factors determine SVE's effectiveness:
soil permeability and constituent volatility. Pertinent
soil measures include hydraulic conductivity, soil
vapor components, gas permeability, and soil mois-
ture content. SVE is generally less practical in moist,
silty or clayey soils. Pertinent measures of volatility
include vapor pressure, water solubility, boiling point,
and Henry's Law constant (chemicals with a dimen-
sionless vapor pressure of greater than 0.5 mm Hg
and a Henry's Law constant greater than 0.01
generally are expected to respond to SVE). Other
important factors are depth to the water table,
potential for water table upwelling, site structures,
subsurface obstructions, and the presence of dense
nonaqueous phase liquids (DNAPLs).
'Robert Stamnes, PE
U.S. Environmental Protection Agency
Region 10 (OEA-095), 1200 Sixth Avenue
Seattle, WA 98101
2John Blanchard, PE
U.S. Environmental Protection Agency (5203G)
Office of Emergency & Remedial Response
Washington, DC 20460
Pagel
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Site investigation should begin with geophysical
methods (electromagnetic survey or ground-pene-
trating radar) to determine the presence and location
of non-aqueous phase liquids, follow with soil-gas
monitoring to locate hot spots, and conclude with
soil-matrix sampling to determine the full extent of
contamination and establish cleanup levels. Bench-
arid field-scale studies may be needed to determine
treatability. The cost of sampling the soil matrix can
be reduced by using a hydropunch or cone pen-
etrometer equipped with sensing devices.
One example illustrates the importance of adequate
site characterization in heterogeneous soil condi-
tions. At the site, a continuous rock layer was dis-
covered several years after SVE had been imple-
mented. The rock layer prevented the vacuum from
reaching the deep soils. The system was modified by
adding horizontal wells, and contaminant levels fell
asymptotically after six years of operation.
At another site, the hydraulic conductivity of soils
was low, and varied by an order of magnitude. In the
vadose zone, air permeability (which characterizes
a soil's resistance to gas flow) was higher than
hydaulic conductivity (resistance to liquid flow) and
varied by only 30 percent. This information allowed
the selection of SVE. Without the air permeability
data, SVE would have been ruled out due to low and
widely varying hydraulic conductivity of site soils.
When a shallow water table is present, it is particu-
larly important to investigate the potential for ground-
water upwelling (which can result in removal of less
vapor and more water) and its effects on SVE (see
the discussion on the effects of moisture on contami-
nant removal by granular activated carbon (GAG)
systems in the Implementation and Air Emissions
Control section of this fact sheet).
At a wetlands site that had been capped since the
early 1980s, a treatability test had to be cut short
because of high concentrations of methane in the
extracted air. The methane was believed to result
from the decomposition of organic matter under the
cap. The final design must include appropriate
treatment based upon the predicted level of meth-
ane. Note that a buildup of methane in a SVE system
can pose a serious explosion risk; another remedy
may be more appropriate.
A cap covering another site had been in place for
some time prior to the SVE system installation. The
contaminants initially present at the site were
trichloroethane (TCE) and perchloroethane (PCE).
Subsequent sampling beneath and along the edges
of the cap revealed that anaerobic conditions under
the cap had reduced the initial compounds to vinyl
chloride. For this reason, the potential for biodegra-
dation of contaminants should be considered when
evaluating the use of caps to enhance SVE systems.
Vinyl chloride is a very toxic compound that can be
released into the air or groundwater.
Determination of Cleanup Levels
Soil criteria and air quality regulations applicable to
SVE operations may vary substantially among
states, and sometimes between localities within the
same state. Accordingly, specific cleanup criteria
should be established before SVE or any cleanup
technology is chosen.
Some RPMs caution that because SVE is imple-
mented easily and initially may yield good results, it
may be selected without adequate attention to
setting achievable soil cleanup levels. In many
cases, it may be difficult to reach cleanup levels
close to background using SVE, because of unsus-
pected subsurface variability or other limiting factors.
Pilot Testing
Pre-design pilot testing is highly recommended to
"fine tune the system" and identify potential problems
before final design. Pilot tests may reveal contami-
nants or areas of contamination that were not identi-
fied previously, even at sites where comprehensive
remedial investigations have been conducted. Cur-
rently, most pilot testing is conducted after the record
of decision (ROD) has been signed, at the pre-
design stage. Several RPMs believe that advancing
the initial pilot test to the remedial investigation stage
would be beneficial, and would accord better with the
concepts of the Superfund Accelerated Cleanup
Model (SACM) and the presumptive remedies
initiatives.
Soil-column testing may be useful for SVE imple-
menation. This laboratory test uses representative
soils from a prospective site to determine the mini-
mum time to reduce the concentrations of VOCs in
the soil matrix. It measures the number of soil pore
volumes of air that must be passed through a col-
umn of contaminated soil to achieve the desired
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contaminant level. That number is divided by the
number of soil pore volumes of air that can be
extracted from the site in one year, yielding the
number of years to clean up the site. The estimated
cleanup time is an important factor in determining the
cost and effectiveness of any cleanup technology.
Column testing can underestimate the time for
remediation if the site is heterogeneous, and may
overestimate the time for remediation due to faster
air flow through the column. This can make it difficult
to transfer the information from column tests to field
situations.
Because the air pollution control system was not
pilot-tested at one site at the same time as soil-air
permeability, the VOC concentration in the discharge
was higher than expected once the system began
operations. Due to the higher concentrations, the
system could operate at only 10 percent of its design
flow capacity and still meet emission standards.
Adequate pilot testing would have revealed this
design flaw.
System Design
Models can be used during the design stage to
predict a system's performance under varying con-
ditions. There are many models available; Air 3D is
a commonly used numeric air flow model. Many
other models are available, but there is no consistent
pattern of use for these models. Several RPMs also
suggest modeling be used to troubleshoot an operat-
ing SVE system. For example, when actual results
did not match the projections at one site, a model
was used to locate the source of contaminant loss in
the system.
Some models are conservative and may not reflect
true site conditions (such as adjacent or overlying
buildings or pavement). For example, one commonly
used model assumes no cover, thereby overestimat-
ing the amount of infiltration that will percolate
through the soil for a given rainfall, thus overestimat-
ing contaminant migration.
Several RPMs agreed that when models are used to
design an SVE system, the input parameters (air
permeability; soil grain size) should reflect site-
specific field conditions. Otherwise, there is a poten-
tial for costly errors in the number and placement of
wells. At one site, for example, a model programmed
with default assumptions resulted in twice as many
required wells than when the model was run using
field measurements. This information should be
collected initially in order to avoid delays later.
Properly designed pilot tests can provide data to
optimize SVE system design. A pilot test at one site
provided measurements to estimate the radius of
influence of an extraction well and the preferential air
flow paths. The setup included one vertical extrac-
tion well and several soil vapor probe nests. Mea-
surements at some probes indicated that the vac-
uum was greater farther away from the extraction
well than at other probes. These data were helpful in
identifying preferential flow paths, which were used
to design the layout of the extraction wells. Nests of
probes also provided data on the vertical variability
of the subsurface, which helped to determine the
screening intervals for the extraction wells. Another
RPM observed that in certain soils, a small radius of
influence for vapor extraction requires the installation
of several nested wells for SVE to perform ade-
quately. These wells should be installed with perme-
able packing materials.
Several RPMs recommend horizontal extraction
trenches for SVE at sites with a shallow water table.
A larger area is cleaned if the air flow is primarily
horizontal. Surface seals are used to avoid drawing
air from the atmosphere into the trenches. The
potential for vertical short-circuiting is increased,
however, by the greater permeability in the trenches
after disturbing the soil. "Short-circuiting" is a
phenomenon where injection air or extracted gasses
follow geological fractures or other highly permeable
zones instead of dispersing evenly throughout the
target zone.
Depending on the characteristics of the site, different
materials can be used to seal the surface. A flexible
membrane liner (FML) can be rolled over the site
and easily removed when the SVE treatment is
complete. FMLs are readily available in a variety of
materials, with high density polyethylene (HOPE)
being the most common. The life of FMLs can be
very short if exposed to sunlight. Alternatives to a
synthetic membrane are clay or bentonite, which can
be applied in any thickness. Clay liners are not as
easily removed as the FMLs, and both types are
susceptible to damage from personnel and equip-
ment. A third alternative—the most common at
commercial or industrial sites—is the use of a con-
crete or asphalt cap. This alternative works well at
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sites that have been paved or will be paved (for
example, a gas station).
Air inlet wells, in conjunction with the extraction
wells, prevent stagnant zones and improve air flow.
At one site, valves on the inlet wells were used to
control the air drawn into the soil. At another site, the
soil to be treated was not very thick and horizontal
extraction wells were used instead of vertical extrac-
tion wells. A ground surface seal prevented short-
circuiting by ambient air, and air inlet wells were
placed in areas of potential stagnation. A surface
seal was necessary to eliminate preferential flow
paths. To prevent stagnation, one RPM recommend-
ed that the SVE system not be shut down for ex-
tended periods when a surface seal is installed.
Stagnation may lead to anaerobic conditions, which
may promote reduction of saturated chlorinated
hydrocarbons to vinyl chloride.
SVE systems designed "from the ground up" may be
more expensive to design and construct than "pack-
aged" systems. Using a "packaged" system or re-
using a successful system may reduce design and
construction costs.
It may be beneficial to use a single company, when-
ever possible, for both the design and operation of
the SVE system, because close collaboration is
necessary before and during pilot testing. If this is
not possible, you might have the designer prepare
performance spec'rficiations for the SVE system. The
construction company then would be responsible to
design and implement the system to meet specific
output parameters. Communication and coordination
especially are important when the design engineers
and the operation engineers work under different
contracts. The design engineers must retain respon-
sibility for the system until it is operating smoothly.
System Enhancements
Air sparging injects clean air into the saturated zone,
increasing aerobic biodegradation and promoting the
physical removal of organics by direct volatilization.
Air sparging should be considered when there are
high concentrations of VOCs in, or immediately
below, the capillary fringe area. Experts caution that
air sparging can induce migration of vapors into
nearby confined spaces or may cause nearby
groundwater monitoring wells to show low levels of
dissolved contaminants because of the volatilization
of gas immediately around the well. SVE is used
sometimes in conjunction with air sparging to remove
contaminants from the vadose zone.
At one site, where air sparging was used to supple-
ment SVE, its effectiveness depended upon the
depth at which the aquifer was sparged. The results
suggested that sparging was effective in the upper
few feet of the saturated zone. The test also indi-
cated that spreading of contaminants was not an
issue, since the sparged zone was shallow. Pulsed
SVE operation was used in conjunction with some of
the sparging activities.
Sparging has appeared to be most effective in the
mid-range permeability soils. Air sparging is less
effective in soils with very high or very low perme-
ability for two reasons: (1) air tends to move around
low permeability regions (clay lenses) and (2) sandy
soils or sand lenses can short-circuit the sparge
influence zone.
Experts have identified several developing technolo-
gies that show potential for improving the effective-
ness of SVE. These include thermal enhancement,
dual phase extraction, pneumatic or hydraulic frac-
turing for tight soils, and co-metabolic processes.
Experiences with system enhancements can be
found in the EPA publication, Soil Vapor Extraction
Enhancement Technology Resource Guide (see
bibliography).
Implementation and Air Emissions Control
Implementation
At one site, a "phased" approach was used to imple-
ment SVE as an interim measure. Wells were first
placed in areas in which the highest levels of con-
taminants were expected. Additional wells were
added over time as the system's behavior became
known. This remedial approach also involved using
a skid-mounted system that was moved to different
extraction locations. This maximized removal by
permitting operators to adjust to variations in con-
tamination and hydrogeologic conditions.
RPMs described several actual and potential site-
specific problems experienced during SVE imple-
mentation. The SVE system at one site was shut
down for two weeks during the winter due to unex-
pected freezing of above-ground piping. The problem
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was alleviated by installing insulation and explosion-
proof heating cable around the piping. Also, for
systems over landfills, heat from subsurface decom-
position could increase the potential for landfill fires.
Air Emissions Control
Vapor contaminants from SVE wells or trenches are
captured by air pollution control equipment. Granular
activated carbon (GAC) units are often used to
remove the VOCs. At sites where high removal rates
are needed due to high concentration, high flow rate,
or both, the carbon absorbers may become satu-
rated quickly; this must be considered during design.
Many SVE systems initially exhibit high VOC re-
moval rates due to flushing and evaporation. The
VOC removal rate then drops to a constant level in
which the mass transfer of the VOC contamination is
controlled by diffusion.
The estimated mass of contaminant will influence the
size and type of air pollution control system selected
for an SVE system. Loadings to the air treatment
system are sometimes estimated incorrectly be-
cause original concentrations of contaminants are
not sustained over time. On the other hand, gross
underestimates of the loading rates of contaminants
on air pollution control systems may lead to health
and safety problems. Excess heat buildup occurs in
the GAC if the rate of contaminant accumulation is
too great. At one site, carbon adsorption was initially
installed as an emission control measure, but, due to
a greater contaminant load than originally expected,
the frequency of carbon replacement was greater
than expected. The carbon adsorption unit had to be
replaced by catalytic oxidation. After removal of the
sources and the immediately surrounding contami-
nated soils, VOC concentrations in the remaining
soils dropped to lower levels, and the system was
switched back to carbon adsorption.
The adsorption capacity of GAC depends on several
factors, including the VOC type, concentration, vapor
temperature, and relative humidity. Isotherms, which
show the mass of contaminants that can be ad-
sorbed per unit mass of carbon at specified tempera-
ture intervals, are available from carbon vendors and
may be used to predict contaminant-specific adsorp-
tion capacity for a specific charcoal-based carbon.
GAC generally has a high affinity for volatile mole-
cules, such as lighter hydrocarbons or chlorinated
compounds. However, some hydrocarbons such as
isopentane have relatively low adsorption capacities.
The relative humidity of the incoming vapor stream
may limit the effectiveness of contaminant removal
by GAC. Water vapor will occupy adsorption sites
preferentially, thereby decreasing the capacity of the
carbon to remove contaminants from the air stream.
The heat generated by pumping and by the com-
pression of vapors often results in an exhaust stream
of elevated temperature. The off-gases from some
vacuum systems must be cooled for efficient treat-
ment prior to entering the carbon adsorption units.
Systems using a resin to adsorb VOCs have been
reported to attain removal efficiencies similar to
GAC. This type of system can be rented, thereby
lowering capital costs. Vendors of air pollution tech-
nologies that compete with carbon adsorption may
provide free technical assistance to ensure that their
systems remain operational throughout the cleanup.
For one system that uses a resin, the VOCs are
purged from the medium by an inert gas, such as
nitrogen, and the contaminant is recovered as a
condensate. At one site where this type of system
was used, a recycler picked up the condensate for
reuse. Storage of the condensate, which in some
cases may be concentrated petroleum product, may
introduce additional design. considerations. For
example, air monitoring or explosion-proof facilities
in the storage area may be required.
Other technologies that have been used for SVE off-
gas treatment are condensation, catalytic oxidation,
incineration, cavitation, photo-oxidation, ultraviolet
oxidation, titanium dioxide, internal combustion
engines, packed-bed thermal processors, biofilters,
reduction processes, and direct discharge.
Monitoring Extracted Vapor
RPMs and experts have recommended monitoring at
the emission source by an electron capture device,
continuous flame ionization detector, or photo-ioni-
zation detector. Periodically, source monitoring
should be supplemented with perimeter monitoring.
Involving the state air permit group early in the
process will expedite the state buy-in to the process.
Special attention should be paid to the concentra-
tions of oxygen in the extracted vapor. High levels of
oxygen may indicate short-circuiting of the intended
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air flow through the system. Conversely, high levels
of carbon dioxide may stem from biological degrada-
tion, which can be exploited by design changes in
the SVE system. However, one specialist has stated
that in alkaline soils, it may be inadvisable to use
changes in concentrations of CO2 to estimate
biodegradation. Alkaline soils can absorb CO2, and
as a result, CO2 formed as a byproduct of biological
activity would not be measured in the vapor ex-
tracted from alkaline soils.
One potential source of error in sampling extracted
vapors occurs when the sampling syringes used
upstream from the air treatment system are diluted
with ambient air due to the vacuum inside the SVE.
The air entering the syringe can be reduced by
capping the syringe immediately after it is withdrawn
from the SVE sampling port or by using a stopcock.
An alternative is to bring the sample to ambient
pressure with filtered air and account for the dilution;
this should be done before the syringe is capped.
Still another approach is to use canister sampling,
which allows the sample to be maintained at the
initial pressure until analyzed.
Overall Performance of the SVE System
The growing interest in this in situ technology is due
in part to its demonstrated effectiveness for remov-
ing volatile compounds, relatively low cost, low
space requirements, and the apparent simplicity of
the system design and operation. However, its
success may be limited by overlying structures or
heterogeneous soils. Even if the SVE system quickly
attains cleanup goals, post-performance monitoring
may be required in case the system needs to be
reactivated.
At one site, the SVE treatment system reportedly
performed better than expected, taking less than one
year to achieve cleanup goals rather than the ex-
pected two to five years. The initial concentration of
PCE in a sandy soil at the site was as high as 1,300
ppm. Soil samples demonstrated that the state's
interim cleanup standards were reached in less than
one year. Negotiations between the PRP and the
state were simplified because the state's interim soil
cleanup standards provided a clear endpoint.
The ease with which SVE systems can be installed
and operated obscures the complexity of vapor
behavior in site-specific subsurface settings. At one
site, analyses of SVE air effluent, and analyses of
groundwater from wells in the vicinity of the SVE
system, indicated that the radius of influence
increased over time. The system was designed to
extract carbon tetrachloride from the soil. Initially,
only carbon tetrachloride was detected in effluent
from the SVE system. However, after the system
had been in operation for a while, trichloroethane
(TCA), dichloroethene (DCE), and trichloroethylene
(TCE) were detected in air and groundwater sam-
ples. The closest source of TCA, DCE, or TCE was
more than 2,000 feet away, well beyond the previ-
ously determined radius of influences for the wells.
Although the reasons for this phenomenon are not
known, one explanation is that the SVE operation
desiccated the soil over time, creating a preferential
pathway to the second contamination source.
At some sites, there are indications that SVE may be
remediating groundwater indirectly. During the time
the SVE has operated at one site, for example, the
concentrations of contaminants detected in ground-
water have dropped significantly. It is uncertain
whether this reduction is linked to the SVE or attribu-
table to natural attenuation. At another site, the
extent of a contaminated groundwater plume was
reduced during SVE operation. The SVE may have
contributed to the removal of contaminants from the
groundwater by enhancing both partitioning and
biodegradation of contaminants.
SVE has not achieved cleanup goals at all sites. The
use of other technologies, such as the excavation of
hot spots or technological enhancements (see page
4), in conjunction with SVE, may assist in achieving
the desired cleanup goals.
Shutting Down the SVE System
Cleanup is usually considered complete when
sampling indicates that residual contaminant levels
in the soil are at or below those required. Confirma-
tory soil borings and soil gas samples usually are
required prior to closure. Additional criteria for
determining when an SVE system should be shut
down include: the cumulative amount of contaminant
removed, extraction well vapor concentrations, and
soil gas contaminant concentration and composition.
When setting cleanup standards for SVE sites, it
should be noted that immobile, high-molecular-
weight compounds cannot be removed by SVE and
will remain in the soil.
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Measuring extracted vapor concentrations gives an
idea of the effectiveness of the system; however, a
decrease is not necessarily strong evidence that soil
concentrations have decreased. Decreases in vapor
concentrations can be attributed also to such other
phenomena as water table upwelling and short-
circuiting. Monitoring extraction well vapor composi-
tion and concentration gives more insight into the
effectiveness of the system. If the total vapor con-
centration decreases without a change in composi-
tion, then the decrease is most likely due to one of
the phenomena listed above. If the decrease in
concentration is accompanied by a shift to less
volatile compounds, then there is probably a change
in the residual contaminant concentration.
Without long-term monitoring it is difficult to deter-
mine whether cleanup levels have been achieved
permanently. Because of this it is sometimes difficult
to persuade state agencies to commit to shutting off
SVE systems once acceptable levels of cleanup
have been reached. Experts recommend that VOC
measurements in the soil matrix be taken again after
soil gas measurements have indicated that the SVE
system has reached steady-state. If later measure-
ments show that the target risk levels have not been
achieved, it may be necessary to reconfigure the
system or enhance it with other technologies such as
biodegradation or capping.
The SVE system at another site was shut down
when VOC levels in the soil gas met the air emission
standards, and the groundwater concentrations met
the maximum contaminant levels established for
drinking water. However, after several months, the
concentrations of contaminants rose above stan-
dards and the system was reactivated. Such a
circumstance may occur because contaminants can
diffuse slowly from less permeable soils and interact
with soil gas and groundwater.
The operating life of one SVE system was based on
its efficiency in removing contaminants relative to
groundwater pumping and treatment. An analysis of
this SVE system revealed that it was more cost-
effective than pump-and-treat systems if it could
remove more than 0.001 pounds per hour of the
target contaminant. Therefore the decision was
made to operate the SVE system until it could no
longer exceed this rate of contaminant removal.
When this occurred, the system was shut down.
At one site, monitoring of soil vapor indicated that the
bonstant levels of removal had met the goals for
reduction of contaminant mass, although pockets of
tightly bound contaminant remained in the vadose
zone and groundwater. Eventually the state con-
sented to shut down the system, but required that
two extraction wells be left in place as a contingency
in case monitoring showed a need for further effort.
Community Involvement
RPMs suggest that cleanup levels be defined as
"goals" for the community early in the remedial
process. The community needs to be told that the
"law of diminishing returns" may ultimately limit the
amount of contamination that can be removed using
SVE or other treatment systems. As more and more
contamination is removed from the soil, and as the
remaining amounts of concentration of contaminants
are lowered, the cost and time necessary to remove
additional contaminants increases. For example, the
time or cost to remove the last 10 percent of the
original mass of contaminants could equal that
required to remove the initial 80 to 90 percent of
contaminants. Understanding of this concept will
avoid unnecessary problems at a later date.
Community involvement efforts at one SVE site were
particularly active and innovative. At this site Re-
gional staff provided a hazardous waste health and
safety training course to anyone in the community
who was interested. This training was attended by
approximately 30 community residents. People from
the community also were trained and hired to oper-
ate and maintain the SVE system and to collect
environmental samples. EPA also established an
analytical laboratory in the town for analysis of
samples collected at the site. The community in-
volvement effort associated with this site resulted in
local acceptance of the system.
While designing SVE pilot studies or SVE systems,
care must be taken to determine the effect of the
SVE systems on the surrounding communities. For
instance, at one site located in a residential area,
noise from the blower and its effect on the surround-
ing residences had to be taken into consideration
during the SVE pilot study. To address community
concerns at another residential site, the system's air
stripper was housed in a colonial-style building
compatible with local architecture.
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Selected Bibliograpy
Innovative Site Remediation Technology, Vac-
uum Vapor Extraction
U.S. EPA, OSWER, Technology Innovation Office,
Washington, DC, April 1995,222 pp.
EPA/542-B-94-002
This monograph is one of a series of eight on
innovative site and waste remediation technologies.
It is the cumulation of a multi-organizational effort
involving over 100 experts over a two-year period. It
provides experienced, practical, professional guid-
ance on the application of this technology.
Abstracts of Remediation Case Studies
Prepared by member Agencies of the Federal
Remediation Treatment Technologies Roundtable:
U.S. EPA, DOD, DOE, DOI, NASA, TVA, and
USCG, Washington, DC, March 1995,101 pp.
NT1S/PB95/182903
This report is a collection of abstracts summariz-
ing 37 case studies of site remediation projects
prepared by federal agencies. The case studies
document the results and lessons learned from early
technology applications. They help establish bench-
mark data on cost and performance, which can lead
to greater confidence in the selection and use of
cleanup technologies.
Soil Vapor Extraction and Bioventing
U.S. Army Corps of Engineers, Washington, DC,
November 1995.
Engineering Manual EM 1110-1-4001
This manual provides practical guidance for the
design and operation of soil vapor extraction and
bioventing systems. The manual describes current
practices for site characterization, system design,
and system startup and operations.
Presumptive Remedies: Site Characterization
and Technology Selection for CERCLA Sites with
Volatile Organic Compounds in Soils
U.S. EPA, OSWER Directive 9355.0-48FS, Wash-
ington, DC, September 1993, 26 pp.
EPA540-F-93-048
PB 93-963346
Presumptive remedies are preferred technolo-
gies for common categories of sites, based on
historical patterns of remedy selection and EPA's
scientific and engineering evaluation of performance
data. Soil vapor extraction (SVE), thermal desorp-
tion, and incineration are the presumptive remedies
for Superfund sites with VOC contaminated soil
assuming the site characteristics meet certain
criteria.
Soil Vapor Extraction Enhancement Technology
Resource Guide: Air Sparging, Bioventing,
Fracturing, Thermal Enhancements
U.S. EPA, OSWER, Technology Innovation Office,
Washington, DC, October 1995, 35 pp.
EPA/542-B-95-003
This report contains an extensive bibliography
of U.S. Environmental Protection Agency and other
agencies' information resources on air sparging,
bioventing, fracturing, and thermal enhancements for
soil vapor extraction.
Evaluation for Unsaturated/Vadose Zone Models
for Superfund Sites
U.S. EPA, ORD, Robert S. Kerr Environmental
Research Laboratory, Ada, OK, March 1994,188 pp
EPA/600/R-93/184,
This manual evaluates several transport models
for unsaturated soils and quantifies the sensitivity
and uncertainty of model outputs to changes in input
parameters.
A Citizen's Guide to Soil Vapor Extraction and
Air Sparging
U.S. EPA, OSWER, Technology Innovation Office,
Washington, DC, March 1996, 4 pp.
EPA/542-F-96-008
This fact sheet presents in lay terms the tech-
nologies, processes, and limitations of soil vapor
extraction (SVE) remediation. It may be a very useful
handout to communities associated with possible
SVE systems.
Soil Vapor Extraction (SVE) Treatment Technol-
ogy Resource Guide
U.S. EPA, OSWER, Technology Innovation Office,
Washington, DC, September 1994, 27 pp.
EPA/542/B-94/007
This report lists an extensive bibliography of
EPA and other agencies' information resources
focusing solely on soil vapor extraction.
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Air Sparging for Site Remediation
Hinchee, R.E., International Symposium on In Situ
and On Site Bioreclamation, 2nd Ed: 1993
San Diego, CA, Lewis Publishing. 1994,142 pp.
This book is a collection of papers focusing on
air sparging as a useful in situ tool for remediation of
sites with hydrocarbon contamination.
Engineering Forum Issue: Considerations in
Deciding to Treat Contaminated Unsaturated
Soils in Situ
U.S. EPA, OSWER, Technology Innovation Office,
Washington, DC, December 1993,27 pp.
EPA/540/S-94/500
This issue paper assists in deciding if in situ
treatment of contaminated soil is a potentially feasi-
ble remedial alternative. It also presents reviews of
in situ technologies. The document contains tables
of generic and technology specific critical factors and
conditions for the use of in situ treatment technolo-
gies and addresses soil vapor extraction.
Engineering Bulletin: Technology Preselection
Data Requirements
U.S. EPA, OSWER.Office of Emergency and Reme-
dial Response, Washington, DC, Oct. 1992, 9 pp.
EPA/540/S-92/009
This bulletin lists soil, water, and contaminant
data elements needed to evaluate the potential
applicability of technologies for treating contaminated
soil and water. It emphasizes the physical, chemical,
soil, and water characteristics for which observations
and measurements should be compiled.
Technology Assessment of Soil Vapor Extraction
and Air Sparging
U.S. EPA, ORD, Risk Reduction Engineering Labo-
ratory, Cincinnati, OH, September 1992
EPA/600/R-92/173
This document summarizes a substantial body
of available information that describes the effective-
ness and characteristics of air sparging systems and
case studies of practical air sparging applications.
Air/Superfund National Technical Guidance
Study Series: Estimation of Air Impacts for Soil
Vapor Extraction (SVE) Systems
U.S. EPA, OAR, Office of Air Quality Planning and
Standards, RTP, NC, January 1992, 91 pp.
EPA/450/1-92/001
This report provides procedures for estimating
the ambient air concentrations associated with soil
vapor extraction (SVE). Procedures are given to
evaluate the effect of the concentration of the con-
taminants in the soil-gas and the extraction rate on
the emission rates and on the ambient air concentra-
tions at selected distances from the SVE system.
In Situ Soil Vapor Extraction Treatment, Engi-
neering Bulletin
U.S. EPA, OSWER, Office of Emergency and Reme-
dial Response, Washington, DC, May 1991,12 pp.
EPA/540/2-91/006
This bulletin provides information on technology
applicability and limitations of soil vapor extraction
technology. It also provides a description of the
technology, types of residuals produced, site require-
ments, the latest performance data, status of the
technology, and sources for further information.
Soil Vapor Extraction Technology: Reference
Handbook, Final Report
U.S. EPA, ORD, Risk Reduction Engineering Labo-
ratory, Cincinnati, OH, February 1991, 316 pp.
EPA/540/2-91/003
This report discusses the basic science of the
subsurface environmental and subsurface monitor-
ing, emission control, and costs. The report also
discusses state-of-the-art technology, the best
approach to optimize systems application, and
process efficiency and limitations.
How to Evaluate Alternative Cleanup Technolo-
gies for Underground Storage Tank Sites
U.S. EPA, OSWER, May 1995
EPA510-B-95-007
This manual provides technical guidance to state
and local regulators in evaluating corrective action
plans for remediating underground storage tank
releases using "alternative technologies." The
manual describes eight cleanup technologies,
including SVE and air sparging, and provides engi-
neering related considerations and parameters for
evaluating the feasibility of a given technology.
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Acknowledgements
Rich Ho, Region 2
Chet Janowski, Region 1
Paul Leonard, Region 3
For Further Information
David J. Becker, PG
U.S. Army Corps of Engineers
Missouri River Division
12565 West Center Road
Omaha, NE 68144
(402) 697-2655
Dominic C. DiGiulio
U.S. Environmental Protection Agency
National Risk Management Research Laboratory
Ada, OK 74821
(405) 436-8605
Soil Vapor Extraction Sites
Soil vapor extraction is the remedy for VOCs in soils at the sites listed below. At some sites, the treatment is
already complete. Some sites are currently operating, and some are in the design phase. This list has been
adapted from the Innovative Treatment Technologies: Annual Status Report (Sixth Edition), September 1994
(EPA 542-R-94-005). This list is not comprehensive.
Hamilton-Standard Division, CT
Kellogg-Deering Well Field, CT
Lincmaster Switch Corporation, CT
United Technologies Corp., CT
Grovcland Wells, MA
Industri-Plcx, MA
Silresim, MA
Silrcsun, MA
Wells G&H OU 1, MA
Union Chemical Co., ME
Mottolo Pig Farm, NH
South Municipal Water Supply Well, NH
Tibbetts Road, NH
Tinkhtm Garage, NH
Peterson/Puritan Inc., RI
Picillo Farm Site, RI
Stamina Mills, RI
A. O. Polymer, NJ
FAA Technical Center, NJ
Garden State Cleaners, NJ
Naval Air Engineering Center, NJ
South Jersey Clothing, NJ
Swope Oil & Chem. Co., NJ
Applied Environmental Services, NY
Circuitron Corporation, NY
Gcnzalc Plating Company, NY
Mettiacc Petrochemicals Company, Inc., NY
Pasley Solvents and Chemicals, Inc., NY
Sinclair Refinery, NY
SMS Instruments, NY
Vestal Water Supply, NY
Jansscn Inc., PR
Upjohn Manufacturing Co., PR
Delaware Sand and Gravel, DE
Bcndix, PA
Cryochcm, PA
Lctterkcnny Army Depot, PA
Lord-Shope Landfill, PA
Raymark, PA
Saergcrtown Industrial Area Site, PA
Tyson's Dump, PA
Arrowhead Associates/Scovill, VA
U.S. Defense General Supply, VA
Hollingsworth Solderless, FL
Robins AFB, GA
ABC Dry Cleaners, NC
Charles Macon Lagoon, NC
JADCO-Hughes, NC
USMC Camp Lejeune Military Base, NC
Medley Farm, SC
SCRDI Bluff Road, SC
Carrier Air Conditioning, TN
Acme Solvent Reclaiming, Inc., IL
American Chemical Services, IN
Enviro. Conservation and Chemical, JJN
Fisher Calo Chem, IN
Main Street Well Field, IN
MIDCO, IN
Seymour Recycling, IN
Wayne Waste Reclamation, IN
Chem Central, MI
Clare Water Supply, MI
Electro-Voice, MI
Kysor of Cadillac Industrial, MI
Peerless Plating, MI
Springfield Township Dump, MI
Sturgis Municipal Well Field, MI
ThermoChem, Inc., MI
Verona Well Field, MI
Long Prairie Groundwater Contamination,
MN
Miami County Incinerator, OH
Pristine, Inc., OH
Skinner Landfill, OH
Zanesville Well Field, OH
City Disposal Corporation Landfill, WI
Hagen Farm Source Control, WI
Muskego Sanitary Landfill, WI
Wausau Groundwater Contamination, WI
Prewitt Abandoned Refinery, NM
Petro-Chemical Systems, Inc., TX
Chemplex, IA
McGraw Edision, IA
Coleman Operable Unit, KS
Cleburn Street, NE
Hastings GW Contamination, NE
Lindsay Manufacturing, NE
Waverly Groundwater Contamination, NE
Chemical Sales Company, CO
Martin Marietta, CO
Rocky Flats, CO
Rocky Mountain Arsenal, CO
Sand Creek Industrial, CO
Utah Power and Light/American Barrel, UT
Hassayampa Landfill, AZ
Motorola 52nd Street, AZ
Phoenix-Goodyear Airport Area, AZ
Tucson International Airport, AZ
Williams AFB, AZ
Barstow Marine Corps Logistics Base, CA
Fairchild Semiconductor, CA
Hexcel, CA
IBM,CA
Intel, CA
Intersil/Siemens, CA
Lawrence Livermore National Laboratory, CA
Lorentz Barrel and Drum, CA
Moffett Air Field, CA
Monolithic Memories/AMD, CA
National Semiconductor, CA
Pacific Coast Pipeline, CA
Purity Oil Sales, CA
Raytheon, CA
Signetics, CA
Solvent Service, CA
Spectra Physics, CA
Van Waters and Rogers, CA
Watkins-Johnson, CA
Eielson Air Force Base, AK
Commencement Bay, WA
Fairchild AFB, WA
Fort Lewis Military Res., WA
Hanford, WA
Pondrers Corner (Lakewood), WA
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