United States
Environmental Protection
Agency
Office of
Solid Waste and
Emergency Response
Directive No. 9355.0-63FS
EPA 540/F-96/008
PB 96-963308
July 1996
SERA
User's Guide to the
VOCs in Soils
Presumptive Remedy
Office of Emergency and Remedial Response
User's Guide
In order to expedite remedy selection at similar types of sites, EPA recommends the use of presumptive remediespreferred
technologies for common categories of sites, based on historical patterns of remedy selection and EPA's scientific and
engineering evaluation of performance data on technology implementation. This User's Guide recommends the soil vapor
extraction (SVE) technology as the preferred presumptive remedy for sites where volatile organic components (VOCs) are
present in soil and treatment is warranted, although the thermal resorption and incineration technologies maybe selected as
presumptive remedies at sites where conditions are appropriate. Presumptive remedies are expected to be used at all
appropriate sites except under unusual site-specific circumstances. This guide is based on the VOCs in Soils Presumptive
Remedy Guidance, Presumptive Remedies: Site Characterization and Technology Selection for CERCLA Sites with Volatile Organic
Compounds in Soils, OSWER 9355.0-48FS. Please refer to that guidance for a more detailed description of how the presumptive
remedy can be applied at sites where volatile organic components (VOCs) are present in soil.
PURPOSE
This User's Guide is intended to aid the site manager. It:
Explains the benefits of using the "presumptive
remedy approach;
Highlights how to decide if the presumptive
remedy approach can be applied to your site;
Explains which presumptive remedy approach to
select for your site (the preferred presumptive
remedial alternative for sites with VOCs in the
soils is soil vapor extraction (SVE));
Describes how to write the feasibility study (FS) or
engineering evaluation/cost analysis (EE/CA) for
a presumptive remedy; and
Outlines administrative record requirements.
In addition, the steps of assembling technologies into
alternatives and reducing alternatives are streamlined since
the number of technologies under consideration have been
minimized. Figure 1 presents the presumptive remedy
technologies for VOCs in soils and important features of
each.
WHY USE THE PRESUMPTIVE
REMEDY APPROACH?
Time and cost savings can be realized by following the
presumptive remedy approach during a remedial
investigation/feasibility study (RI/FS). First, since a preferred
cleanup technology can be identified prior to or early in the
RI, technology-specific remedial design data can be collected
and analyzed sooner. In addition, use of the presumptive
remedy approach eliminates the need to:
Identify potential treatment technologies
Screen technologies in your site-specific FS or
EE/CA.
Figure 1. Presumptive Remedies for VOCs in Soils
Soil Vapor Extraction (SVE): The preferred
presumptive remedy
In-situ process
Removes contaminants from vadose zone
soils by inducing air flow through the soil
Highly cost effective alternative
Vapor treatment may be required
Thermal Resorption
Soil excavation required
Uses direct or indirect heat to vaporize VOCs
from soil
Vapor treatment may be required
Incineration
Soil excavation required
Employs thermal decomposition via oxidation
Destroys the organic fraction of the waste
Vapor treatment may be required
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CAN YOU APPLY THE VOCS IN SOILS PRESUMPTIVE REMEDY APPROACH TO YOUR SITE?
In order to determine if you can use the presumptive remedy
approach at your site, you need to answer the following
questions. Regardless of the status of your RI or removal
evaluation, these questions can be addressed once you
establish the nature of any VOC and non-VOC waste
contained in the soil, where treatment is warranted.
Are VOCs present in soil or sludge?
VOCs include halogenated and non-halogenated organics
such as trichloroethylene, carbon tetrachloride, acetone and
benzene. A complete a list of typical VOCs is found in the
master VOCs presumptive remedy guidance referenced on
page 1. If your site does not have VOCs in the soil, then this
User's Guide is not applicable for use in remedy selection at
the site.
Are non-VOCs present that will preclude the use of
the presumptive remedy guidance?
For sites with a mixture of VOCs and other contaminants in
soil, the presumptive remedies should be considered only if
they also can also be effective in removing the non-VOC
contaminants, or can be used in combination with other
remedies. For combination remedies, this presumptive
remedy approach can be used to select the VOC portion of the
remedy. For example, sites with VOCs and metals
commingled in soil may be effectively remediated by
employing SVE to remove VOCs and fixation or solidification
to address the metal contamination. The presumptive remedy
approach can still be used for the selection of the SVE remedy
whereas a traditional FS analysis would be necessary for the
treatment of metals.
In conclusion, if VOCs are present in soils and non-VOCs do
not preclude a VOC remedy, you may also select the
presumptive remedy for the VOC component of the site.
Have all key stakeholders been notified?
Please keep in mind that it is important to notify the
community, (especially any community working groups)
the State, and any PRPs that a presumptive remedy is being
considered at your site. It is important to get their buy-in
early in the cleanup process.
This notification should begin as early as possible and can
continue to occur throughout the RI/FS in the form of fact
sheets and agenda items during public meetings. Early
discussions about the rationale for presumptive remedies creates
confidence in both the technology and remedy selection process.
Once a candidate presumptive remedy site has been
identifiied and a response action involving treatment is
warranted under the NCP, you can decide which of the 3
VOCs in soils presumptive remedy technologies to select.
WHICH VOCs IN SOILS PRESUMPTIVE REMEDY IS BEST FOR MY SITE?
Once you have determined that your site is a candidate for a
presumptive remedy, SVE should be analyzed first since it is
the preferred presumptive remedial alternative. In most
cases, SVE is extremely cost effective and can be implemented
in-situ. The SVE Checklist (Figure 2) can help you decide if
SVE is appropriate at your site.'The questions posed in the
SVE Checklist provide a preliminary "first-cut" assessment
of basic site characteristics that relate to potential SVE
treatment effectiveness. Your site is a strong candidate for
SVE if you answer "yes"' to all of these questions. At this
point, you may wish to assume SVE as the preferred
technology for VOC remedial action at your site. Therefore,
you may immediately proceed to an SVE Pilot Study and a
Presumptive Feasibility Study (see p. 3).
For the purposes of this User's Guide, the terms "Presumptive
FS or EE/CA" refer to the FS or EE/CA developed at sites
where the presumptive remedy is applied. The SVE Checklist
is not a definitive screening test for SVE. So, even if you
answer "no" to one or more of these questions, SVE may still
be an appropriate presumptive technology for your site, but
greater technical analysis may be warranted. Considerations
such as best professional judgment and community opinion
should guide your decision to proceed with an SVE Pilot
Study to confirm the appropriateness of the SVE technology
at your site.
If SVE is determined to be ineffective based on site-specific
circumstances, thermal desorption is the next technology that
should be assessed for use at your site. Thermal Desorption is
the primary VOC presumptive remedy at sites where soil
excavation is required to remediate a non-VOC contaminant.
At some sites, public perception is that incineration can be
disruptive to a community, and it has been ruled out due to that
perception. Be aware of this if you prove incineration as a
remedy. For a complete discussion of the characteristics that
affect the use of SVE, thermal resorption and incineration
technologies, refer to Tables 3 and 4 of the master VOC
presumptive remedy guidance.
Figure 2. SVE Checklist
Site Characteristics2
Soil Permeability > 106cm2
Soil Moisture Content < 50%?
VOC Vapor Pressure > 0.5mm Hg?
Dimensionless Henry's constants > 0.01?
Soil/Air Filled Porosity < 40%?
Low organic carbon content ?
Yes
No
'If you are scoping an RI or a removal evaluation, the information requested in Figure 2 should be identified as a "presumptive remedy data
need" along with common data needs for an RI/FS. As you develop the RI/FS Work Plan, you should establish site-specific data quality
objectives for each set of RI data needs. All presumptive remedy data needs should be collected during the first round of environmental
data collection of the RI if not before.
2See Table 4 of the VOCs in Soils Presumptive Remedy Guidance for a description for each of the terms listed in Figure 2.
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HOW DO I WRITE THE FS OR EE/CA FOR A PRESUMPTIVE REMEDY?
After determining that your site can use a VOCs in soils
presumptive remedy, the next step is to prepare a presumptive
FS or EE/CA. Note that for non-time-critical removals, you
can prepare an EE/CA. Regardless of the status of your RI
or removal evaluation, the Presumptive FS or EE/CA for the
soil remedy should begin immediately.
As highlighted on page 1, the presumptive remedy approach
allows you to streamline and focus the FS or EE/CA by
eliminating the technology screening step because EPA has
already conducted this step on a generic basis in the document
Feasibility Study Analysis for VOCs in Soils Sites. Basically,
only the "No- Action" alternative and presumptive remedy
alternative require further consideration. If SVE is
appropriate, the other presumptive technologies (thermal
desorption incineration) may be eliminated from further
consideration. To tailor the Presumptive FS to the specific
conditions at your site, you may first need to refine the
presumptive remedy alternative, as necessary. For example,
if off gas treatment is required, the technology for off gas
treatment is not selected presumptively and should be
addressed in the FS. As shown in Figure 3, the presumptive
technology should be matched with an appropriate mix of
conventional and innovative vapor treatment technologies.
The final step of the Presumptive FS would consist of
analyzing the No-Action and Presumptive Remedy
alternatives against the nine NCP evaluation criteria.
An example format for critical elements of a Presumptive FS
is provided in Figure 4. Please note that it is advisable to
expand the Introduction Chapter of your Presumptive FS or
EE/CA to include a brief discussion of the presumptive
remedy approach and justification for using this approach at
your site.
You may wish to consider technologies that enhance the
performance of the presumptive remedy based on site-
specific conditions. For example, SVE enhancements include
bioventing, capping, hot air injection, steam injection, and
subsurface mining. Additionally, you may consider using a
phased approach to designing and implementing an SVE
system similar to EPA's suggested phased approach to
characterizing and remediating contaminated groundwater
sites. In order to maximize engineering flexibility during
remedial design and remedial action, it is not always necessary
to address potential enhancements in your Presumptive FS.
Only where: (a) there is a high degree of confidence that the
enhancement is essential for cost-effective remediation; or,
(b) the addition of the enhancement significantly changes the
cost or scope of the base SVE alternative, should such
enhancements be included in the Presumptive FS. For more
information on whether to include enhancements in your FS
and determining what would require changes to a ROD, see
"Guide to Addressing Pre-ROD and Post-ROD changes,"
OSWER 9355.3-02FS-4, April 1991.
Figure 3. Example of a Possible SVE
Alternative Refinement
Alternative 1- No Action
Alternative 2- SVE with No Off Gas Treatment
Alternative 3- SVE with Off Gas Treatment (e.g., acti-
vated carbon, catalytic oxidation, flameless thermal oxi-
dation, resin adsorption, etc.)
Alternative 4- SVE with Off Gas Treatment and Capping
Figure 4. Example Format For
Critical Elements of A Presumptive FS
I. Introduction
A. Background to the Site
B. Introduction to the Presumptive Remedy
Approach
C. Determination to use the Presumptive Remedy
Approach
II. Description of the No Action Alternative, the
Presumptive Remedy Alternatives, and ARARs
III. Detailed (Nine Criteria) Analysis of the No Action
Alternative and the Presumptive Remedy Alternative
IV. Description of the Preferred Alternative
A. Rationale for the Preferred Alternative
ADMINISTRATIVE RECORD REQUIREMENTS
You must compile an administrative record in accordance
with the Final Guidance on Administrative Records for Selecting
CERCLA Response Actions, OSWER Directive 9833.3A.1. The
administrative record must contain both EPA guidance and
site-specific information documenting the selection of the
VOCs in soils presumptive remedy. Other required EPA
guidance documents include
Presumptive Remedies: Policies and Procedures, OSWER
9355.0-47FS
Presumptive Remedies: Site Characterization and
Technology Selection for CERCLA Sites with VOCs in
Soils, OSWER 9355.0-48FS
Feasibility Study Analysis for VOCs in Soils Sites, OSWER
9356.0-01. [Note The administrative record file index
should include a notice specifying the location of and
times when public access is available to the generic file
of backup materials used in developing this document.
The generic file contains background materials such as
technical references and previous feasibility studies.
Each EPA Regional office has a copy of this file.]
"Guide to Principal Threat and Low Level Threat Wastes,
OSWER 9380.3-06FS
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