vvEPA
United States
Environmental Protection
Agency
Office of Emergency and
Remedial Response
Washington, DC 20460
Office of
Research
Cincinnati, OH 45268
Superfiind
EPA/540/2-91/006
May 1991
Engineering Bulletin
In Situ Soil Vapor Extraction
Treatment
Purpose
Section 121(b) of the Comprehensive Environmental Re-
sponse, Compensation, and Liability Act (CERCLA) mandates
the Environmental Protection Agency (EPA) to select remedies
that "utilize permanent solutions and alternative treatment
technologies or resource recovery technologies to the maxi-
mum extent practicable" and to prefer remedial actions in
which treatment "permanently and significantly reduces the
volume, toxicity, or mobility of hazardous substances, pollut-
ants, and contaminants as a principal element." The Engi-
neering Bulletins are a series of documents that summarize
the latest information available on selected treatment and site
remediation technologies and related issues. They provide
summaries of and references for the latest information to help
remedial project managers, on-scene coordinators, contrac-
tors, and other site cleanup managers understand the type of
data and site characteristics needed to evaluate a technology
for potential applicability to their Superfund or other hazard-
ous waste site. Those documents thtit describe individual
treatment technologies focus on remedial scoping needs.
Addenda will be issued periodically to update the original
bulletins.
Abstract
Soil vapor extraction (SVE) is designed to physically re-
move volatile compounds, generally from the vadose or un-
saturated zone. It is an in situ process employing vapor
extraction wells alone or in combination with air injection
wells. Vacuum blowers supply the motive force, inducing air
flow through the soil matrix. The air strips the volatile com-
pounds from the soil and carries them to the screened ex-
traction well.
Air emissions from the systems are typically controlled by
adsorption of the volatiles onto activated carbon, thermal
destruction (incineration or catalytic oxidation), or condensa-
tion by refrigeration [1, p. 26].*
SVE is a developed technology that has been used in
commercial operations for several years. It was the selected
remedy for the first Record of Decision (ROD) to be signed
under the Superfund Amendments and Reauthorization Act
of 1986 (the Verona Well Field Superfund Site in Battle Creek,
* [reference number, page number]
Michigan). SVE has been chosen as a component of the ROD
at over 30 Superfund sites [2] [3] [4] [5] [6].
Site-specific treatability studies are the only means of
documenting the applicability and performance of an SVE
system. The EPA Contact indicated at the end of this bulletin
can assist in the location of other contacts and sources of
information necessary for such treatability studies.
The final determination of the lowest cost alternative will
be more site-specific than process equipment dominated.
This bulletin provides information on the technology applica-
bility, the limitations of the technology, the technology de-
scription, the types of residuals produced, site requirements,
the latest performance data, the status of the technology, and
sources for further information.
Technology Applicability
In situ SVE has been demonstrated effective for removing
volatile organic compounds (VOCs) from the vadose zone.
The effective removal of a chemical at a particular site does
not, however, guarantee an acceptable removal level at all
sites. The technology is very site-specific. It must be applied
only after the site has been characterized. In general, the
process works best in well drained soils with low organic
carbon content. However, the technology has been shown to
work in finer, wetter soils (e.g., clays), but at much slower
removal rates [7, p. 5].
The extent to which VOCs are dispersed in the soil—
vertically and horizontally—is an important consideration in
deciding whether SVE is preferable to other methods. Soil
excavation and treatment may be more cost effective when
only a few hundred cubic yards of near-surface soils have
been contaminated. If volume is in excess of 500 cubic yards,
if the spill has penetrated more than 20 or 30 feet, or the
contamination has spread through an area of several hundred
square feet at a particular depth, then excavation costs begin
to exceed those associated with an SVE system [8] [9]
[10, p. 6].
The depth to groundwater is also important. Groundwa-
ter level in some cases may be lowered to increase the volume
of the unsaturated zone. The water infiltration rate can be
Printed on Recycled Paper
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Table 1
Effectiveness of SVE on General
Contaminant Groups For Soil
Contaminant Croups
X
|
°
§
i
1
1
Halogenated volatiles
Halogenated semivolatiles
Nonhalogenated volatiles
Nonhalogenated semivolatiles
PCBs
Pesticides
Dioxins/Furans
Organic cyanides
Organic corrosives
Volatile metals
Nonvolatile metals
Asbestos
Radioactive materials
Inorganic corrosives
Inorganic cyanides
Oxidizers
Reducers
Effectiveness
Soil
m
T
•
•
a
a
a
a
a
a
a
a
a
a
a
a
T
• Demonstrated Effectiveness: Successful treatability test at some
scale completed
T Potential Effectiveness: Expert opinion that technology will work
LI No Expected Effectiveness: Expert opinion that technology will not
work
controlled by placing an impermeable cap over the site. Soil
heterogeneities influence air movement as well as the loca-
tion of chemicals. The presence of heterogeneities may make
it more difficult to position extraction and inlet wells. There
generally will be significant differences in the air permeability
of the various soil strata which will affect the optimum design
of the SVE facility. The location of the contaminant on a
property and the type and extent of development in the
vicinity of the contamination may favor the installation of an
SVE system. For example, if the contamination exists beneath
a building or beneath an extensive utility trench network, SVE
should be considered.
SVE can be used alone or in combination with other
technologies to treat a site. SVE, in combination with
groundwater pumping and air stripping, is necessary when
contamination has reached an aquifer. When the contamina-
tion has not penetrated into the zone of saturation (i.e.,
below the water table), it is not necessary to install a ground-
water pumping system. A vacuum extraction well will cause
the water table to rise and will saturate the soil in the area of
the contamination. Pumping is then required to draw the wa-
ter table down and allow efficient vapor venting [11, p. 169].
SVE may be used at sites not requiring complete remedia-
tion. For example, a site may contain VOCs and nonvolatile
contaminants. A treatment requiring excavation might be
selected for the nonvolatile contaminants. If the site required
excavation in an enclosure to protect a nearby populace from
VOC emissions, it would be cost effective to extract the volatiles
from the soil before excavation. This would obviate the need
for the enclosure. In this case it would be necessary to vent
the soil for only a fraction of the time required for complete
remediation.
Performance data presented in this bulletin should not be
considered directly applicable to other Superfund sites. A
number of variables such as the specific mix and distribution
of contaminants affect system performance. A thorough
characterization of the site and a well-designed and conducted
treatability study are highly recommended.
The effectiveness of SVE on general contaminant groups
for soils is shown in Table 1. Examples of constituents within
contaminant groups are provided in the "Technology Screen-
ing Guide For Treatment of CERCLA Soils and Sludges" [12].
This table is based on the current available information or
professional judgment where no information was available.
The proven effectiveness of the technology for a particular site
or waste does not ensure that it will be effective at all sites or
that the treatment efficiencies achieved will be acceptable at
other sites. For the ratings used in this table, demonstrated
effectiveness means that, at some scale, treatability tests showed
that the technology was effective for that particular contami-
nant and matrix. The ratings of potential effectiveness, or no
expected effectiveness are both based upon expert judgment.
Where potential effectiveness is indicated, the technology is
believed capable of successfully treating the contaminant group
in a particular matrix. When the technology is not applicable
or will probably not work for a particular combination of
contaminant group and matrix, a no-expected-effectiveness
rating is given. Another source of general observations and
average removal efficiencies for different treatability groups is
contained in the Superfund Land Disposal Restrictions (LDR)
Guide #6A, "Obtaining a Soil and Debris Treatability Variance
for Remedial Actions," (OSWER Directive 9347.3-06FS, July
1989) [13] and Superfund LDR Guide #6B, "Obtaining a Soil
and Debris Treatability Variance for Removal Actions," (OSWER
Directive 9347.3-07FS, December 1989) [14].
Limitations
Soils exhibiting low air permeability are more difficult to
treat with in situ SVE. Soils with a high organic carbon
content have a high sorption capacity for VOCs and are more
difficult to remediate successfully with SVE. Low soil tem-
perature lowers a contaminant's vapor pressure, making vola-
tilization more difficult [11].
Sites that contain a high degree of soil heterogeneity will
likely offer variable flow and desorption performance, which
will make remediation difficult. However, proper design of
the vacuum extraction system may overcome the problems of
heterogeneity [7, p. 19] [15].
Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
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It would be difficult to remove soil contaminants with
low vapor pressures and/or high water solubilities from a site.
The lower limit of vapor pressure for effective removal of a
compound is 1 mm Hg abs. Compounds with high water
solubilities, such as acetone, may be removed with relative
ease from arid soils. However, with normal soils (i.e., mois-
ture content ranging from 10 percent to 20 percent), the
likelihood of successful remediation drops significantly be-
cause the moisture in the soil acts as a sink for the soluble
acetone.
Technology Description
Figure 1 is a general schematic of the in situ SVE process.
After the contaminated area is defined, extraction wells (1)
are installed. Extraction well placement is critical. Locations
must be chosen to ensure adequate vapor flow through the
contaminated zone while minimizing vapor flow through
other zones [11, p. 170]. Wells are typically constructed of
PVC pipe that is screened through the zone of contamination
[11 ]. The screened pipe is placed in a permeable packing; the
unscreened portion is sealed in a cement/bentonite grout to
prevent a short-circuited air flow direct to the surface. Some
SVE systems are installed with air injection wells. These wells
may either passively take in atmospheric air or actively use
forced air injection [9]. The system must be designed so that
any air injected into the system does not result in the escape
of VOCs to the atmosphere. Proper design of the system can
also prevent offsite contamination from entering the area
being extracted.
The physical dimensions of a particular site may modify
SVE design. If the vadose zone depth is less than 10 feet and
the area of the site is quite large, a horizontal piping system or
trenches may be more economical than conventional wells.
An induced air flow draws contaminated vapors and
entrained water from the extraction wells through headers—
usually plastic piping—to a vapor-liquid separator (2). There,
entrained water is separated and contained for subsequent
treatment (4). The contaminant vapors are moved by a
vacuum blower (3) to vapor treatment (5).
Vapors produced by the process are typically treated by
carbon adsorption or thermal destruction. Other methods—
such as condensation, biological degradation, and ultraviolet
oxidation—have been applied, but only to a limited extent.
Process Residuals
The waste streams generated by in situ SVE are vapor and
liquid treatment residuals (e.g., spent granular activated car-
bon [GAC]), contaminated groundwater, and soil tailings from
drilling the wells. Contaminated groundwater may be treated
and discharged onsite [12, p. 86] or collected and treated off-
site. Highly contaminated soil tailings from drilling must be
collected and may be either cleaned onsite or sent to an
offsite, permitted facility for treatment by another technology
such as incineration.
Site Requirements
SVE systems vary in size and complexity depending on
the capacity of the system and the requirements for vapor
and liquid treatment. They are typically transported by vehicles
ranging from trucks to specifically adapted flatbed semitrailers;
therefore, a proper staging area for these vehicles must be
incorporated in the plans.
Figure 1
Process Schematic of the In Situ Soil Vapor Extraction System
Clean Air
i
Extraction
Well
(1)
Air Vent or
Injection Well
\
r
Extracted u___, L
Viioor Vapor- •
vapor __ , |nii,H •]
t
1
(2) [ Separator J
f «
Air Vent or
Injection Well
Ground Surface
Contaminated
Vadose
Zone
r
™ ^-
Process Residual
V Liquid b CleanWater
Treatment • ^
y Process Residual^
Monitoring
Well
Water Table
Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
-------
Adequate access roads must be provided to bring mobile
drilling rigs onsite for construction of wells and to deliver
equipment required for the process (e.g., vacuum blowers,
vapor-liquid separator, emission control devices, GAC canisters).
A small commercial-size SVE system would require about
1,000 square feet of ground area for the equipment. This
area does not include space for the monitoring wells which
might cover 500 square feet. Space may be needed for a
forklift truck to exchange skid-mounted GAC canisters when
regeneration is required. Large systems with integrated vapor
and liquid treatment systems will need additional area based
on vendor-specific requirements.
Standard 440V, three-phase electrical service is needed.
For many SVE applications, water may be required at the site.
The quantity of water needed is vendor- and site-specific.
Contaminated soils or other waste materials are hazard-
ous, and their handling requires that a site safety plan be
developed to provide for personnel protection and special
handling measures. Storage should be provided to hold the
process product streams until they have been tested to deter-
mine their acceptability for disposal or release. Depending
upon the site, a method to store soil tailings from drilling
operations may be necessary. Storage capacity will depend
on waste volume.
Onsite analytical equipment, including gas chromato-
graphs and organic vapor analyzers capable of determining
site-specific organic compounds for performance assessment,
make the operation more efficient and provide better infor-
mation for process control.
Performance Data
SVE, as an in situ process (no excavation is involved), may
require treatment of the soil to various cleanup levels man-
dated by federal and state site-specific criteria. The time
required to meet a target cleanup level (or performance ob-
jective) may be estimated by using data obtained from bench-
scale and pilot-scale tests in a time-predicting mathematical
model. Mathematical models can estimate cleanup time to
reach a target level, residual contaminant levels after a given
period of operation and can predict location of hot spots
through diagrams of contaminant distribution [16].
Table 2 shows the performance of typical SVE applica-
tions. It lists the site location and size, the contaminants and
quantity of contaminants removed, the duration of operation,
and the maximum soil contaminant concentrations before
treatment and after treatment. The data presented for specific
contaminant removal effectiveness were obtained, for the
most part, from publications developed by the respective SVE
system vendors. The quality of this information has not been
determined.
Midwest Water Resources, Inc. (MWRI) installed its
VAPORTECH™ pumping unit at the Dayton, Ohio site of a
spill of uncombusted paint solvents caused by a fire in a paint
warehouse [19]. The major VOC compounds identified were
acetone, methyl isobutyl ketone (MIBK), methyl ethyl ketone
(MEK), benzene, ethylbenzene, toluene, naphtha, xylene, and
other volatile aliphatic and alkyl benzene compounds. The
site is underlain predominantly by valley-fill glacial outwash
within the Great Miami River Valley, reaching a thickness of
over 200 feet. The outwash is composed chiefly of coarse,
clean sand and gravel, with numerous cobbles and small
boulders. There are two outwash units at the site separated
by a discontinuous till at depths of 65 to 75 feet. The upper
outwash forms an unconfined aquifer with saturation at a
depth of 45 to 50 feet below grade. The till below serves as
an aquitard between the upper unconfined aquifer and the
lower confined to semiconfined aquifer. Vacuum withdrawal
extended to the depth of groundwater at about 40 to 45 feet.
During the first 73 days of operation, the system yielded
3,720 pounds of volatiles and after 56 weeks of operation,
had recovered over 8,000 pounds of VOCs from the site.
Closure levels for the site were developed for groundwater
VOC levels of ketones only. These soil action levels (acetone,
810 u.g/1; MIBK, 260 u.g/1, and MEK, 450 ng/l) were set so that
waters recharging through contaminated soils would result in
Table 2.
Summary of Performance Data for In Situ Soil Vapor Extraction
Sfte_
Industrial - CA [1 7]
Sheet Metal Plant - Ml [18]
Prison Const. Site- Ml [19]
Sherwin-Williams Site - OH [19]
Upjohn- PR [20][21]
UST Bellview - FL [7]
Verona Wellfield - Ml [7][22]
Petroleum Terminal -
Owensboro, KY [19]
SITE Program - Groveland MA [7]
Size
5,000 cu yds
165,000 cu yds
425,000 cu yds
7,000,000 cu yds
35,000 cu yds
12,000 cu yds
6,000 cu yds
Contaminants
TCE
PCE*
TCA
Paint solvents
CCI4
BTEX
TCE, PCE, TCA
Gasoline, diesel
TCE
Quantity
removed
30kg
59kg
~
4,100kg
7,000 kg
?,700 kg
2,700 kg
...
Duration of
operation
440 days
35 days
90 days
6 mo
3yr
7 mo
Over 1 yr
6 mo
Soil concentrations (mg/kg)
max. before after
treatment treatment
0.53
5600
3.7
38
2200
97
1380
>5000
0.06
0.70
0.01
0.04
<0.005
<0.006
Ongoing
1 .0 (target)
590kg
56 days
96.1
4.19
*PCE = Perchloroethylene
Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
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groundwater VOC concentrations at or below regulatory
standards. The site met all the closure criteria by June 1988.
A limited amount of performance data is available from
Superfund sites. The EPA Superfund Innovative Technology
Evaluation (SITE) Program's Groveland, Massachusetts, dem-
onstration of the Terra Vac Corporation SVE process produced
data that were subjected to quality assurance/quality control
tests. These data appear in Table 2 [7, p. 29] and Table 3 [7,
p. 31]. The site is contaminated by trichloroethylene (TCE), a
degreasing compound which was used by a machine shop
that is still in operation. The subsurface profile in the test area
consists of medium sand and gravel just below the surface,
underlain by finer and silty sands, a clay layer 3 to 7 feet in
depth, and—below the clay layer—coarser sands with gravel.
The clay layer or lens acts as a barrier against gross infiltration
of VOCs into subsequent subsoil strata. Most of the subsur-
face contamination lay above the clay lens, with the highest
concentrations adjacent to it. The SITE data represent the
highest percentage of contaminant reduction from one of the
four extraction wells installed for this demonstration test. The
TCE concentration levels are weighted average soil concen-
trations obtained by averaging split spoon sample concentra-
tions every 2 feet over the entire 24-foot extraction well
depth. Table 3 shows the reduction of TCE in the soil strata
near the same extraction well. The Groveland Superfund Site
is in the process of being remediated using this technology
[2].
The Upjohn facility in Barceloneta, Puerto Rico, is the first
and, thus far, the only Superfund site to be remediated with
SVE. The contaminant removed from this site was a mixture
containing 65 percent carbon tetrachloride (CCI4) and 35
percent acetonitrile [20]. Nearly 18,000 gallons of CCI4 were
extracted during the remediation, including 8,000 gallons
that were extracted during a pilot operation conducted from
January 1983 to April 1984. The volume of soil treated at the
Upjohn site amounted to 7,000,000 cubic yards. The respon-
sible party originally argued that the site should be considered
clean when soil samples taken from four boreholes drilled in
the area of high pretest contamination show nondetectable
levels of CCI4. EPA did not accept this criterion but instead
required a cleanup criteria of nondetectable levels of CCI4 in all
the exhaust stacks for 3 consecutive months [21]. This re-
quirement was met by the technology and the site was con-
sidered remediated by EPA.
Approximately 92,000 pounds of contaminants have been
recovered from the Tyson's Dump site (Region 3) between
November 1988 and July 1990. The site consists of two
unlined lagoons and surrounding areas formerly used to store
chemical wastes. The initial Remedial Investigation identified
no soil heterogeneities and indicated that the water table was
20 feet below the surface. The maximum concentration in
the soil (total VOCs) was approximately 4 percent. The
occurence of dense nonaqueous-phase liquids (DNAPLs) was
limited in areal extent. After over 18 months of operation, a
number of difficulties have been encountered. Heterogene-
ities in soil grain size, water content, permeability, physical
structure and compaction, and in contaminant concentrations
have been identified. Soil contaminant concentrations of up
to 20 percent and widespread distribution of DNAPLs have
been found. A tar-like substance, which has caused plugging,
has been found in most of the extraction wells. After 18
months of operation, wellhead concentrations of total VOCs
have decreased by greater than 90 percent [23, p. 28].
As of December 31,1990, approximately 45,000 pounds
of VOCs had been removed from the Thomas Solvent Raymond
Road Operable Unit at the Verona Well Field site (Region 5). A
pilot-scale system was tested in the fall of 1987 and a full-scale
operation began in March, 1988. The soil at the site consists
of poorly-graded, fine-to-medium-grained loamy soils under-
lain by approximately 100 feet of sandstone. Groundwater is
located 16 to 25 feet below the surface. Total VOC concen-
trations in the combined extraction well header have de-
creased from a high of 19,000 ug/1 in 1987 to approximately
1,500ug/1 in 1990 [22].
Table 3
Extraction Well 4: TCE Reduction In Soil Strata—EPA Site Demonstration (Groveland, MA) [7, p. 31]
Depth (ft)
Description of strata
0-2 Med. sand w/gravel
2-4 Lt. brown fine sand
4-6 Med. stiff It. brown fine sand
6-8 Soft dk. brown fine sand
8-10 Med. stiff brown sand
10-12 V. stff It. brown med. sand
12-14 V. Stiff brown fine sand w/silt
14-16 M. stff grn-brn clay w/silt
16-18 Soft wet clay
18-20 Soft wet clay
20-22 V. stiff brn mecl-coarse sand
22-24 V. stiff brn mecl-coarse w/gravel
Hydraulic
Conductivity (cm/s)
10-4
lO^1
10s
10s
10^
10^
10-4
10-"
io-8
10-8
io-4
103
Soil TCE concentration (mg/kg)
Pre-treatment Post-treatment
2.94
29.90
260.0
303.0
351.0
195.0
3.14
ND
ND
ND
ND
6.17
ND
ND
39.0
9.0
ND
ND
2.3
ND
ND
ND
ND
ND
ND - Nondetectable level
Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
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An SVE pilot study has been completed at the Colorado
Avenue Subsite of the Hastings (Nebraska) Groundwater Con-
tamination site (Region 7). Trichloroethylene (TCE), 1,1,1-
trichloroethane (TCA), and tetrachloroethylene (PCE) occur in
two distinct unsaturated soil zones. The shallow zone, from
the surface to a depth of 50 to 60 feet, consists of sandy and
clayey silt. TCE concentrations as high as 3,600 ug/1 were
reported by EPA in this soil zone. The deeper zone consists of
interbedded sands, silty sands, and gravelly sands extending
from about 50 feet to 120 feet. During the first 630 hours of
the pilot study (completed October 11,1989), removal of
approximately 1,488 pounds of VOCs from a deep zone
extraction well and approximately 127 pounds of VOCs from
a shallow zone extraction well were reported. The data
suggest that SVE is a viable remedial technology for both soil
zones [24].
As of November, 1989, the SVE system at the Fairchild
Semi-conductor Corporation's former San Jose site (Region 9)
has reportedly removed over 14,000 pounds of volatile con-
taminants. Total contaminant mass removal rates for the SVE
system fell below 10 pounds per day on October 5, 1989 and
fell below 6 pounds per day in December, 1989. At that time,
a proposal to terminate operation of the SVE system was
submitted to the Regional Water Quality Control Board for
the San Francisco Bay Region [25, p.3].
Resource Conservation and Recover/ Act (RCRA) LDRs
that require treatment of wastes to best demonstrated avail-
able technology (BOAT) level:, prior to land disposal may
sometimes be determined to be applicable or relevant and
appropriate requirements for CERCLA response actions. SVE
can produce a treated waste that meets treatment levels set
by BOAT but may not reach these treatment levels in all cases.
The ability to meet required treatment levels is dependent
upon the specific waste constituents and the waste matrix. In
cases where SVE does not meet these levels, it still may, in
certain situations, be selected for use at the site if a treatability
variance establishing alternative treatment levels is obtained.
EPA has made the treatability variance process available in
order to ensure that LDRs do not unnecessarily restrict use of
alternative and innovative treatment technologies. Treatabil-
ity variances are justified for handling complex soil and debris
matrices. The following guides describe when and how to
seek a treatability variance for soil and debris: Superfund LDR
Guide #6A, "Obtaining a Soil arid Debris Treatability Variance
for Remedial Actions" (OSWER Directive 9347.3-06FS, July
1989) [1 3], and Superfund LDR Guide #6B, "Obtaining a Soil
and Debris Treatability Variance for Removal Actions" (OSWER
Directive 9347.3-07FS, December 1989) [14]. Another ap-
proach could be to use other treatment techniques in series
with SVE to obtain desired treatment levels.
Technology Status
During 1989, at least 1 7 RODs specified SVE as part of
the remedial action [5]. Since 1982, SVE has been selected as
the remedial action, either alone or in conjunction with other
treatment technologies, in more than 30 RODs for Superfund
sites [2] [3] [4] [5] [6]. Table 4 presents the location, primary
contaminants, and status for these sites [3] [4] [5]. The
technology also has been used to clean up numerous under-
ground gasoline storage tank spills.
A number of variations of the SVE system have been
investigated at Superfund sites. At the Tinkhams Garage Site
in New Hampshire (Region 1), a pilot study indicated that
SVE, when used in conjunction with ground water pumping
(dual extraction), was capable of treating soils to the 1 ppm
clean-up goal [26, 3-7] [27]. Soil dewatering studies have
been conducted to determine the feasability of lowering the
water table to permit the use of SVE at the Bendix, PA Site
(Region 3) [28]. Plans are underway to remediate a stockpile
of 700 cubic yards of excavated soil at the Sodeyco Site in Mt.
Holly, NC using SVE [29].
With the exception of the Barceloneta site, no Superfund
site has yet been cleaned up to the performance objective of
the technology. The performance objective is a site-specific
contaminant concentration, usually in soil. This objective may
be calculated with mathematical models with which EPA
evaluates delisting petitions for wastes contaminated with
VOCs [30]. It also may be possible to use a TCLP test on the
treated soil with a corresponding drinking water standard
contaminant level on the leachate.
Most of the hardware components of SVE are available
off the shelf and represent no significant problems of avail-
ability. The configuration, layout, operation, and design of
the extraction and monitoring wells and process components
are site specific. Modifications may also be required as dic-
tated by actual operating conditions.
On-line availability of the full-scale systems described in
this bulletin is not documented. System components are
highly reliable and are capable of continuous operation for
the duration of the cleanup. The system can be shut down, if
necessary, so that component failure can be identified and
replacemnts made quickly for minimal downtime.
Based on available data, SVE treatment estimates are
typically $50/ton for treatment of soil. Costs range from as
low as $10/ton to as much as $150/ton [7]. Capital costs for
SVE consist of extraction and monitoring well construction;
vacuum blowers (positive displacement or centrifugal); vapor
and liquid treatment systems piping, valves, and fittings (usu-
ally plastic); and instrumentation [31]. Operations and main-
tenance costs include labor, power, maintenance, and moni-
toring activities. Offgas and collected groundwater treatment
are the largest cost items in this list; the cost of a cleanup can
double if both are treated with activated carbon. Electric
power costs vary by location (i.e., local utility rates and site
conditions). They may be as low as 1 percent or as high as 2
percent of the total project cost.
Caution is recommended in using these costs out of
context, because the base year of the estimates vary. Costs
also are highly variable due to site variations as well as soil and
contaminant characteristics that impact the SVE process. As
contaminant concentrations are reduced, the cost effective-
ness of an SVE system may decrease with time.
Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
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Table 4
Superfund Sites Specifying SVE as a Remedial Action
Site
Location (Region)
Primary Contaminants
Status
Groveland Weils 1 & 2
Kellogg-Deering Well Field
South Municipal Water
Supply Well
Tinkham Garage
Wells G & H
FAA Technical Center
Upjohn Manufacturing Co.
Allied Signal Aerospace-
Bendix Flight System Div.
Henderson Road
Tyson's Dump
Stauffer Chemical
Stauffer Chemical
Sodyeco
Kysor Industrial
Long Prairie
MIDCO 1
Miami County Incinerator
Pristine
Seymour Recycling
Verona Well Field
Wausau Groundwater
Contamination
South Valley/
General Electric
Hastings Groundwater
Contamination
Sand Creek Industrial
Fairchild Semiconductor
Fairchild Semiconductor/
MTV-1
Fairchild Semiconductor/
MTV-2
Intel Corporation
Raytheon Corporation
Motorola 52nd Street
Phoenix-Goodyear Airport
Area (also Litchfield
Airport Area)
Croveland,
Morwalk, CT (1 )
Peterborough, NH(1)
Londonderry, NH (1)
Woburn, MA(1)
Atlantic County, Nj (2)
Barceloneta, PR (2)
South Montrose, PA (3)
Upper Merion Township,
PA (3)
Upper Merion Township,
PA (3)
Cold Creek, AL (4)
Lemoyne, AL (4)
Mt. Holly, NC (4)
Cadillac, Ml (5)
Long Prairie, MN (5)
Gary, IN (5)
Troy, OH (5)
Cincinnati, OH (5)
Seymour, IN (5)
Battle Creek, Ml (5)
Wausau, Wl (5)
Albuquerque, NM (6)
Hastings, NE (7)
Commerce City, CO (8)
San Jose, CA (9)
Mountain View, CA (9)
Mountain View, CA (9)
Mountain View, CA (9)
Mountain View, CA (9)
Phoenix, A2 (9)
GxxJyear, AZ (9)
TCE
PCE, TCE, and BTX
PCE, TCE, Toluene
PCE, TCE
PCE, TCE
BTX, PAHs, Phenols
CCI4
TCE
PCE, TCE, Toluene, Benzene
PCE, TCE, Toluene, Benzene,
Trichloropropane
CCL4, pesticides
CCL4, pesticides
TCE, PAHs
PCE, TCE,Toluene, Xylene
PCE, TCE, DCE, Vinyl chloride
BTX, TCE, Phenol, Dichloro-
methane, 2-Butanone,
Chlorobenzene
PCE; TCE; Toluene
Benzene; Chloroform; TCE;
1,2-DCA; 1,2-DCE
TCE; Toluene; Chloromethane;
cis-1, 2-DCE; 1,1,1 -DCA;
Chloroform
PCE, TCA
PCE, TCE
Chlorinated solvents
CCL4 ,Chloroform
PCE, TCE, pesticides
PCE, TCA, DCE, DCA,
Vinyl chlorides, Phenols,
and Freon
PCE, TCA, DCE, DCA,
Vinyl chlorides, Phenols,
and Freon
PCE, TCA, DCE, DCA,
Vinyl chlorides, Phenols,
and Freon
PCE, TCA, DCE, DCA,
Vinyl chlorides, Phenols,
and Freon
PCE, TCA, DCE, DCA,
Vinyl chlorides, Phenols,
and Freon
TCA, TCE, CCL4 , Ethylbenzene
TCE, DCE, MEK
SfTE demonstration complete [2][7]
Full-scale Remediation in design
Pre-design [3] [5] [6]
Pre-design completion expected in the fail
of 1991
Pre-design pilot study completed
In design
In design
Project completed in 1988
Pre-design tests and dewatering
study completed
Pre-design
In operation (since 11 /88) [23]
Pre-design [5] [6]
Pre-design [5] [6]
Design approved [29]
In design; pilot studies in progress [3] [5] [6]
SVE construction expected in the Fall of 1991
[3H6J
In Design [3] [5] [6]
Pre-design [3] [5] [6]
Pre-design [3] [6]
Pre-design investigation completed [32]
Operational since 3/81 [22]
Pre-design [3] [5] [6]
Pilot studies scheduled for [4] [6]
Summer of 1991
Pilot studies completed for [24]
Colorado Ave. fit Far-Marco
subsites
Pilot study completed [33]
Operational since 1988, [25]
Currently conducting
resaturation studies
Pre-design [3] [5]
Pre-design [3] [5]
Pre-design [3] [5]
Pre-design [3] [5]
Pre-design [3] [4] [6]
North Unit - In design [34]
South Unit - pilot study completed
Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
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EPA Contact
Technology-specific questions regarding SVE may be di-
rected to:
Michael Gruenfeld
U.S. Environmental Protection Agency
Releases Control Branch
Risk Reduction Engineering Laboratory
2890 Woodbridge Ave.
Building 10(MS-104)
Edison, NJ 08837
(FTS) 340-6924 or (908) 321 -6924
Acknowledgements
This bulletin was prepared for the U.S. Environmental
Protection Agency, Office of Research and Development (ORD),
Risk Reduction Engineering Laboratory (RREL), Cincinnati, Ohio,
by Science Applications International Corporation (SAIC), and
Foster Wheeler Enviresponse Inc. (FWEI) under contract No.
68-C8-0062. Mr. Eugene Harris served as the EPA Technical
Project Monitor. Gary Baker was SAIC's Work Assignment
Manager. This bulletin was authored by Mr. Pete Michaels of
FWEI. The author is especially grateful to Mr. Bob Hillger and
Mr. Chi-Yuan Fan of EPA, RREL, who have contributed signifi-
cantly by serving as technical consultants during the devel-
opment of this document.
The following other Agency and contractor personnel
have contributed their time and comments by participating in
the expert review meetings and/or peer reviewing the docu-
ment:
Dr. David Wilson
Dr. Neil Hutzler
Mr. Seymour Rosenthal
Mr. Jim Rawe
Mr. Clyde Dial
Mr. Joe Tillman
Vanderbilt University
Michigan Technological University
FWEI
SAIC
SAIC
SAIC
8
Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
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REFERENCES
1. Cheremesinoff, Paul N. Solvent Vapor Recovery and
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2. Records of Decision System Database, Office of Emer-
gency and Remedial Response, U.S. Environmental
Protection Agency, 1989.
3. Innovative Treatment Technologies: Semi-Annual Status
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1989.
5. ROD Annual Report, FY 1989. EPA/540/8-90/006,
April 1990.
6. Personal Communications with Regional Project
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Environmental Protection Agency, 1989. (SITE Report).
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Team. Verona Well Field-Thomas Solvent Co. Operable
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Operation, and Monitoring of In Situ Soil Venting
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1 3. Superfund LDR Guide #6A: Obtaining a Soil and Debris
Treatability Variance for Remedial Actions. OSWER
Directive 9347.3-06FS, U.S. Environmental Protection
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Treatability Variance for Removal Actions. OSWER
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Puerto Rico, 1984.
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Field Site, Battle Creek, Ml, April 1991.
23. Terra Vac Corporation. An Evaluation of the Tyson's Site
On-Site Vacuum Extraction Remedy Montgomery
County, Pennsylvania, August 1990.
24. IT Corporation. Final Report-Soil Vapor Extraction Pilot
Study, Colorado Avenue Subsite, Hastings Ground-
Water Contamination Site, Hastings, Nebraska, August,
1990.
25. Canonie Environmental. Supplement to Proposal to
Terminate In-Situ Soil Aeration System Operation at
Fairchild Semiconductor Corporation's Former San Jose
Site, December 1989.
26. Malcom Pirnie, Tinkhams Garage Site, Pre-Design Study,
Londonderry, New Hampshire - Final Report, July 1988.
27. Terra Vac Corp., Tinkhams Garage Site Vacuum Extrac-
tion Pilot Test, Londonderry, New Hampshire, July 20,
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28. Environmental Resources Management, Inc. Dewater-
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space, South Montrose, PA, December 1990.
29. Letter Correspondence from Sandoz Chemicals Corpo-
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Environmental Health, and Natural Resources, RE:
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30. Federal Register, Volume 50, No. 229, Wednesday,
November 27, 1985, pp. 48886-48910.
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ment Technologies. EPA/600/2-90/011, U.S. Environ-
mental Protection Agency, 1990.
32. Hydro Geo Chem, Inc. Completion Report, Pre-Design
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Seymour, Indiana, February 1990.
Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
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33. Groundwater Technology, Inc. Report of Findings - 34. Hydro Ceo Chem, Inc. Results and Interpretation of the
Vacuum Extraction Pilot Treatability at the Sand Creek Phoenix Goodyear Airport SVE Pilot Study, Goodyear,
Superfund Site (OU-1), Commerce City, Colorado, Arizona, May 1989.
March 1990.
10 Engineering Bulletin: In Situ Soil Vapor Extraction Treatment
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