~0~   v|  DNAPL Remediation:   Selected Projects
,^m&J  Approaching  Regulatory  Closure	
              STATUS UPDATE
    Section                              Page

    1.0 Overview	1
    2.0 Challenges of DNAPL Characterization
       and Remediation	2
    3.0 Overview of DNAPL Remediation
       Technologies	6
    4.0 DNAPL Remediation Projects	7
    5.0 Summary of Findings	8
    References	10
    Appendix A -  DNAPL Remediation Project
                Profiles
    Appendix B -  Suspected DNAPL Thresholds
                Based on Solubility Relative to One
                Percent of Aqueous Solubility
    Appendix C -  Examples of Treatment Technology
                Providers
  1.0  OVERVIEW

  Remediation of dense nonaqueous-phase liquids
  (DNAPLs) in contaminated media such as soil
  and ground water is a particularly challenging
  problem.  DNAPLs, which consist of compounds
  such as chlorinated solvents and polycyclic
  aromatic hydrocarbons (PAHs), tend to sink in the
  subsurface and continue to release dissolved
  contaminants to surrounding media for an
  extended period of time. Significant quantities of
  DNAPLs are present at chlorinated solvent-
  contaminated sites such as manufacturing and
  degreasing facilities, dry cleaners, wood treaters,
  and former manufactured  gas plants (MGPs).
  Chlorinated solvents such as tetrachloroethene
  (PCE) and trichloroethene (TCE) are the most
  frequently occurring types of soil and ground
  water contaminants at Superfund and other
  hazardous waste sites. Site owners will likely
  spend billions of dollars over the next several
  decades to clean up DNAPL-impacted sites (U.S.
  Environmental Protection Agency [EPA] 2000).
The physical and chemical properties of
DNAPLs, including their relatively low
solubility, high specific gravity, and tendency to
remain sorbed to organic materials in an aquifer,
make DNAPLs difficult to locate and
characterize in the subsurface, and can impact
the effectiveness of conventional remedial
technologies such as groundwater pump-and-
treat (P&T).  Further, the presence of DNAPLs
can make it more difficult to reach regulatory
closure. As such, source reduction is
increasingly being used to remove or destroy
DNAPLs in the subsurface. Once a DNAPL
source is addressed, residual ground water
plumes may be more amenable to less aggressive
remedial techniques such as monitored natural
attenuation (MNA) (EPA 1999b).

The following types of technologies are
increasingly being used to treat DNAPL sources:

•  In situ thermal treatment
•  In situ chemical oxidation
•  Surfactant/co-solvent flushing
•  In situ bioremediation

Other technologies that have been used for
treating DNAPL sources include ground water
extraction (e.g., P&T or recirculation),
excavation, and containment (e.g., engineered
caps and slurry walls).
  EPA is interested in identifying additional sites
  where DNAPLs are present, a remedial
  technology has been used, and the site has since
  reached regulatory closure or is approaching
  closure. Please contact Rich Steimle at EPA's
  Office of Superfund Remediation and Technology
  Innovation to discuss further, at (703) 603-7195,
  or e-mail steimle.richard@epa.gov.
                                      Solid Waste and Emergency
                                      Response (5102G)
                           EPA 542-R-04-016
                              December 2004
                             http://clu-in.org

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                                  DNAPL Remediation:  Selected Projects Approaching Regulatory Closure
This paper is a status update on the use of
DNAPL source reduction remedial technologies,
and provides information about recent projects
where regulatory closure has been reached or
projects that are approaching regulatory closure,
following source reduction. Information is
presented about the challenges associated with
DNAPL remediation, the types of in situ
technologies used,  and data and findings
concerning the relative effectiveness of field
applications of these technologies. Appendix A
contains project profiles for eight field
applications that illustrate some of the findings
presented in this paper.

This paper is intended for use  by project
managers, federal and state regulatory staff, site
owners, consultants, and technology providers.
It provides current  information about selected
experiences with the technologies mentioned
above. Users of this paper are expected to have a
basic understanding of site remediation
approaches and terminology and are referred to
the references cited in this paper for further
information about specific remedial technologies.
 Mention of trade names or commercial products
does not constitute endorsement or
recommendation for use.

All the projects highlighted in this paper are
practical examples  of the use of in situ
technologies to  remediate DNAPL-impacted sites
in order to achieve  or partially achieve regulatory
requirements. Most of these sites were not
research test sites and did not involve direct
measurement of DNAPL quantity. For this
reason, significant uncertainties exist regarding
how the treatment of the DNAPL sources
affected the dissolved plumes. There currently is
no consensus among remediation professionals
about when source reduction should be
recommended over containment.  It is expected
that over the next few years, more applications of
aggressive source treatment technologies will be
completed. Information from  these applications
will be helpful in further understanding how best
to address the challenge of DNAPL
contamination.
Demonstration programs for DNAPL
remediation technologies have been performed or
are ongoing at several national test center sites
such as Dover Air Force Base, Delaware, and
Cape Canaveral, Florida.  Further information
about these programs and specific test results are
available from the following sources:

•  Federal Remediation Technologies
   Roundtable (FRTR) (http://www.frtr.gov]
•  Environmental Security Technology
   Certification Program (ESTCP)
   (http://www. eslcp. org)
•  Strategic Environmental Research and
   Development Program (SERDP)
   (http://www.serdp.org)
•  Interagency DNAPL Consortium
   (http://www.getf.org/dnaplguest)

2.0  CHALLENGES OF DNAPL
     CHARACTERIZATION AND
     REMEDIATION

As discussed  above, the physical and chemical
properties of DNAPLs pose challenges in the
characterization and remediation of this
contaminant in the subsurface.  The following
discussion provides additional detail about the
key challenges of treating DNAPLs that can
affect the ability of a site to reach regulatory
closure.

Locating and Verifying the Presence of
DNAPLs - DNAPL source zones are often
difficult to locate, and the size and spatial
distribution of the source zone are difficult to
determine, especially for complex scenarios such
as sites with large contaminant masses in
complex environments  (for example,
heterogeneous or fractured bedrock
environments).  With DNAPL characterization, it
is important to have accurate site characterization
and conceptual site models. Techniques that
have been effective in locating and
characterizing DNAPLs include surface
geophysics, direct-push sampling (sometimes
incorporating fluorescence sensors), membrane
interface probes, or partition well interface
testing (Kram and others 2001).
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                                  DNAPL Remediation: Selected Projects Approaching Regulatory Closure
                      Recent EPA Report by Expert Panel on DNAPL Remediation

  In December 2003, EPA issued a report prepared by an expert panel titled "The DNAPL Remediation
  Challenge: Is There a Case for Source Depletion?" (EPA 600/R-03/143). The panel, chaired by Michael
  Kavanaugh and P. Suresh Rao and under the direction of David Burden of the EPA National Risk Management
  Research Laboratory, examined seven questions related to DNAPLs.  These questions focused on potential
  benefits and adverse impacts of DNAPL source depletion, appropriate performance metrics, technologies for
  source characterization, the anticipated performance of depletion technologies, available tools for predicting
  performance, factors affecting technology application, and the decision-making process. The following are
  selected conclusions from the report (the full report is available at http://www.epa.gov/ada/piibs/reports.html):

  •  Substantial progress in development and deployment of technologies for DNAPL source zone
     characterization and mass depletion has been made in North America and Europe over the past two decades.

  •  Both conventional technologies (such as P&T and excavation) and innovative in situ technologies are capable
     of partial source zone depletion.

  •  As far as the panel is aware, there is no documented, peer-reviewed case study of DNAPL source zone
     depletion beneath the water table where U.S. drinking water standards or maximum contaminant levels
     (MCL) have been achieved and sustained throughout the affected subsurface volume, regardless of the in situ
     technology applied. Nonetheless, at a number of DNAPL-impacted sites, closure of the sites has been
     reported, signifying achievement of remedial action objectives (RAO).
In addition, it is difficult to verify the presence of
DNAPLs through direct observation. Generally,
their presence is indirectly estimated. One
approach is based on ground water concentration
data and the "1 percent of solubility" rule-of-
thumb (EPA 1992). Under this approach,
DNAPL is suspected to be present when the
concentration of a chemical in ground water is
greater than 1 percent of its pure-phase solubility
(for example, when the concentration of PCE  is
greater than 2,000 micrograms per liter [ug/L] in
the dissolved phase [1 percent of its pure-phase
solubility of 200,000 ug/L], PCE is inferred to be
present as a DNAPL). Appendix B provides
additional information on the 1 percent solubility
concentrations for selected chlorinated solvents.

The Interstate Technology and Regulatory
Council (ITRC) recently published Technology
Overview: An Introduction to Characterizing
Sites Contaminated with DNAPLs (ITRC 2003a),
which discusses characterization approaches,
data collection techniques, and investigation
methodologies for sites contaminated with
DNAPLs.
EPA has published a new report, Site
Characterization Technologies for DNAPL
Investigations (EPA 2004a) about specific
technologies useful in locating, quantifying, and
verifying the presence of DNAPLs. This report
addresses the use of both geophysical and non-
geophysical techniques for DNAPL
investigations.

DNAPL as a Continuing Contaminant Source
and Dissolved Plume Management - Because
DNAPLs have a tendency to remain sorbed to
organic materials in an aquifer, they can act as
continuing sources of ground water
contamination. The DNAPL will continue to
dissolve, making it more difficult to manage the
dissolved-phase plume.  For example, at sites
with P&T systems, the presence of DNAPL
source zones most likely will extend the time
needed to remediate the site, resulting in
increased operation and maintenance (O&M)
costs (EPA 1999a).

Treatment Technology Selection and
Approach - There are a number of challenges
associated with the treatment of DNAPLs. These
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                                  DNAPL Remediation: Selected Projects Approaching Regulatory Closure
include the effectiveness of partial source
removal; uncertainties in the location and
quantity of DNAPL in the subsurface; limited
availability of performance and cost data for
using innovative technologies to treat DNAPLs;
and uncertainties about the long-term
effectiveness of DNAPL source reduction.
There is an ongoing debate within the
remediation community regarding the utility of
partial source removal or reduction, where some
but not all of the DNAPL source is removed or
destroyed.  Although EPA policy generally
supports  active attention to sources (EPA 1993,
1999b, 2002), the published results of modeling
and/or laboratory-scale column studies suggest
that almost all DNAPL must be removed before
site risks are significantly reduced, at least in the
short term (Freeze and McWhorter 1997; Sale
and McWhorter 2001). A recent report issued by
the National Academy of Sciences emphasizes
the need  to perform site-specific analyses of the
effectiveness of partial source reduction in order
to better guide and justify remedy selection
(National Research Council 2003). ITRC also
published a recent report, Strategies for
Monitoring the Performance of DNAPL Source
Zone Remedies (DNAPLs-5) (ITRC 2004).  This
report describes approaches to performance
monitoring while implementing various in situ
remedial technologies for DNAPL treatment.

Because  of uncertainties about the volume and
distribution of DNAPLs and limited cost and
performance data, project managers often do not
select innovative in situ technologies. In
addition, innovative technologies are often
presumed to have higher costs than conventional
systems such as P&T. Remediation
professionals often compare costs for an
innovative technology to that for a conventional
technology based on the life-cycle costs.  Life-
cycle costs  include the up-front cost for
construction as well as the cost for O&M over
the expected duration of the remediation. Net
present value calculations are  also typically
incorporated into life-cycle cost estimation to
factor in  the time-value of money.  Although the
construction cost for an innovative technology
may be higher than that for a traditional
technology, the costs for O&M over the life  of
the remediation may be lower, depending on the
system's scale and design. These lower lifetime
O&M costs may offset the higher up-front costs
for an innovative technology.  Factors affecting
O&M costs include  the frequency and level of
maintenance and the length of time for remedial
system operation. With some conventional
technologies like P&T, O&M costs might
include the costs associated with routine
maintenance, such as replacement of pumps and
valves, as well as longer-term maintenance
issues, such as replacement of extraction wells
over the life of the extraction system and the
maintenance, waste  disposal, and power
requirements for the treatment system.

Variation in Cleanup Levels and Closure
Criteria - At sites contaminated with DNAPL,
there is variation in the cleanup levels and
closure criteria, including a wide range of
quantitative goals as well as goals that specify
qualitative objectives only, as shown below.
     Examples of remedial action objectives
       established as qualitative criteria

      "Clean up of ground water to the extent
         practicable for the source area"

     "Removal of the source area, followed by
              natural attenuation"
Table 1 illustrates variation in site-specific
cleanup levels (for 44 sites across the country)
for soil and groundwater contaminated with
DNAPL constituents. As shown in this table,
cleanup levels for individual chlorinated solvents
have varied by as much as five orders of
magnitude.
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                                   DNAPL Remediation: Selected Projects Approaching Regulatory Closure
                       Table 1. Examples of Variation in Cleanup Levels for
                          DNAPL Constituents in Soil and Ground Water1
Contaminant
Maximum
Contaminant
Level
("8/L)
Range of Cleanup Levels at
Selected Sites (Number of Sites)2
Soil (mg/kg)
Ground Water (ug/L)
Chlorinated Ethenes
PCE
TCE
cis-l,2-DCE
1,1-DCE
5
5
70
7
0.03 - 529 (12)
0.015-20,400(11)
71,000(1)
0.08(1)
0.7 - 8.85 (16)
1 - 17,500 (25)
0.38 - 50,000 (9)
7(2)
Chlorinated Ethane
1,1,1-TCA
200
6 - 28.6 (2)
30 - 8,850 (5)
Chlorinated Methanes
Carbon Tetrachloride
Chloroform
Methylene Chloride
5
None
None
2-6(2)
0.3 - 6 (2)
5.77 - 227,000 (2)
5(2)
10(1)
2,000 (1)
Notes:

  1.   Cleanup levels are determined site specifically based on risk and resource factors, such as location, current
      and future use, contaminant transport, and technology capabilities
      Range of Cleanup Levels at Selected Sites based on information provided for 44 chlorinated solvent cleanup
      projects in cost and performance case study reports on the FRTR Website (http://www.frtr.gov).  The FRTR
      case study reports were reviewed to identify projects that provide cleanup levels for specific chlorinated
      solvent compounds. These projects are located across the United States and involve use of a variety of
      cleanup technologies.
Some states follow a tiered approach to
developing remediation objectives for
contaminated soil and ground water. For
example, Illinois EPA (IEPA) uses the Tiered
Approach to Corrective Action Objectives
(TACO) (Illinois EPA 2004) as defined in Title
35 of Illinois Administrative Code (Illinois
Administrative Code).  In this approach, the
remediation objectives emphasize the protection
of human health and also take into account site-
specific conditions and land use to provide
flexibility to site owners and operators in
developing site-specific remediation objectives.
In lEPA's Tier I approach,  the site owner or
operator compares site sample analytical results
to baseline remediation objectives  contained in
"lookup tables". These objectives are based on
simple, conservative models. A Tier II
evaluation involves consideration of data
gathered in Tier I,  in addition to the physical and
chemical properties of the contaminants, site-
specific soil and ground water parameters, and
the application of institutional controls and
engineered barriers.  Tier III involves more
complex evaluations than performed in Tier II,
including sites where remediation is limited due
to physical barriers or complex sites requiring
full-scale risk assessments or alternative
modeling.  An example of where a Tier III
approach was used in site closure is the Former
Manufacturing Facility, Skokie, Illinois,  where
Tier III cleanup levels for addressing chlorinated
solvents in ground water were approved by
IEPA. (Sites in bold print are discussed in
greater detail later in this paper)
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                                  DNAPL Remediation:  Selected Projects Approaching Regulatory Closure
Other examples of the tiered approach closure
criteria being used at the sites that received
closure letters include Texas Tier I Protective
Concentration Levels (PCLs) in soil and Tier I
commercial/industrial Class 3 risk-based
exposure levels for TCE and PCE in ground
water (Parkwood Former Dry Cleaner,
Texas), and Indiana Tier II cleanup goals for
industrial land use (Confidential Chemical
Manufacturing Facility, Portland, Indiana).

3.0  OVERVIEW OF DNAPL
     REMEDIATION TECHNOLOGIES

This section provides an overview of selected
technologies that have been used to treat DNAPL
sources.  Individual project profiles presented in
Appendix A document the use of these in situ
technologies as  well as P&T and excavation.
Examples of service providers for these
technologies are identified in Appendix C.
Additional information about in situ treatment
technologies is available in the  sources cited
below and in  the FRTR compilation of
remediation technology assessment reports
(http://www.frtr.gov/multisiterepoits.htm).

Several engineering considerations are associated
with the applications of these technologies. For
example, before the application of in situ thermal
treatment, issues to be considered include
potential migration of mobilized contaminants,
health and safety issues associated with high
temperatures  and pressures, and potential thermal
impacts on regional ground water. For the
application of in situ chemical oxidation, it is
important to consider the health and safety issues
associated with chemical oxidants such as ozone,
which can cause severe burns.

In Situ Thermal Treatment - This includes
technologies that employ heat in the source zone
to volatilize or mobilize DNAPL. Various
approaches have been used, including steam
injection (also referred to as steam-enhanced
extraction, or SEE), electrical resistive heating
(ERH; one variation of ERH is  referred to as six-
phase heating, or SPH), thermal conductive
heating (also referred to as in situ thermal
desorption, or ISTD), hot water injection, hot air
injection, and radio frequency (RF)-heating. In
some applications, high temperature conditions
have been created that destroy DNAPLs in place
through pyrolysis. In situ thermal treatment
technologies are described in more detail in In
Situ Thermal Treatment of Chlorinated Solvents:
Fundamentals and Field Applications (EPA
2004).

In Situ Chemical Oxidation - This includes
technologies that involve injecting chemical
oxidants or other amendments directly into the
source zone to destroy DNAPL constituents in
place. Three of the more common chemical
oxidants used for DNAPL treatment are
permanganate (either sodium or potassium
permanganate), hydrogen peroxide (when used
with iron catalysts, this is generally referred to as
Fenton's chemistry or Fenton's reagent), and
ozone. The injected oxidants react with the
contaminant, breaking chemical bonds and
producing degradation products such as carbon
dioxide, water, and chloride. In situ chemical
oxidation is described in greater detail in
Technical and Regulatory Guidance for In Situ
Chemical  Oxidation of Contaminated Soil and
Ground Water (ITRC 2001) and Technology
Status Review:  In Situ Oxidation (ESTCP
1999).

Surfactant/Co-solvent Flushing - This includes
technologies that enhance DNAPL removal
through injection and subsequent extraction of
chemicals to solubilize and/or mobilize DNAPL
constituents. The chemicals typically used are
aqueous surfactant solutions, co-solvents that
lower the interfacial tension (including alcohols
such as ethanol or isopropyl alcohol), or
electrolytes that aid in contaminant
solubilization.  The chemicals are injected into a
system of wells designed to  "sweep" the DNAPL
zone within the aquifer. The chemical "flood"
and the solubilized or mobilized DNAPL are
extracted from the subsurface and are separated
and treated aboveground.  Surfactant/co-solvent
flushing technology is described in greater detail
in Technical and Regulatory Guidance for
Surfactant/Co-solvent Flushing of DNAPL
Source Zones (ITRC 2003b).
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                                  DNAPL Remediation: Selected Projects Approaching Regulatory Closure
In Situ Bioremediation - This includes
technologies that use engineered conditions to
enhance the biological activity of subsurface
microbial populations.  Typically, electron donor
substrates such as lactate or molasses are
introduced into the subsurface, stimulating native
microbes to degrade contaminants through the
process of reductive dechlorination.
Nonindigenous microbes also have been
introduced into the subsurface (referred to as
bioaugmentation).  Although more commonly
applied to dissolved-phase plumes, in situ
bioremediation has been used at sites with
DNAPL sources.  In situ bioremediation is
described in greater detail in Engineered
Approaches to In Situ Bioremediation of
Chlorinated Solvents: Fundamentals and Field
Applications (EPA 2000).

Zero Valent Iron Injection - This includes
technologies that involve the injection of liquid
atomized and reactive zero-valent iron (ZVI)
powder into the DNAPL source zone.
Introduction of ZVI into the subsurface  promotes
chemical reduction of chlorinated solvents. Use
of ZVI for reduction of chlorinated solvents has
been studied in permeable reactive barriers
(PRBs) that treat the dissolved phase of the
contaminants present in the ground water plume.
ZVI delivery into the source area sometimes is
used in conjunction with pneumatic fracturing.
At this time, the technology is primarily being
used at field demonstration scale and only
limited information is available about cost and
performance of larger-scale applications. (U.S.
Department of the Navy [Navy] 2003)

4.0  DNAPL REMEDIATION PROJECTS

Eight remediation projects are presented to
illustrate remediation technologies that have been
used at contaminated sites for DNAPL treatment.
 The projects share the following characteristics:

•  They have been conducted at sites with
   DNAPL contamination (DNAPL has been
   observed or is suspected based on elevated
   contaminant concentrations).
•  The sites have reached regulatory closure or
   have ongoing remediation that is making
   substantial progress toward closure.

•  A destruction or removal technology
   (preferably at full scale) has been used to
   address the DNAPL source zone.

•  Information is available that describes the
   destruction or removal activities.

Table 2, at the end of this paper, summarizes
information about the eight DNAPL remediation
projects. These include three projects using in
situ thermal treatment, four projects using in situ
chemical oxidation, and one project using in situ
bioremediation. For each of the projects, efforts
were made to contact regulatory officials and
technology providers in order to obtain
information that was current as of Spring 2004.
Appendix A provides a brief profile for each of
the projects shown in Table 2.  Specific sources
used in preparation of the profiles as well as
points of contact for further information are
provided in the profiles.

It is important to note that the eight projects
discussed in this paper are examples of the types
of projects where DNAPLs have been
remediated; these projects are not intended to be
statistically representative of the range of
projects performed. For the eight projects,
DNAPL was reported to have been observed at
one site and was reported as suspected at seven
sites, based on elevated contaminant
concentrations in ground water (using the 1
percent solubility rule of thumb).

In addition to the eight project profiles, the
following sources provide further information
about specific DNAPL-contaminated sites where
aggressive in situ treatment technologies  have
been used:

•  "In Situ Treatment of Groundwater
   Contaminated with NAPL Contamination:
   Fundamentals and Case Studies." Chicago,
   Illinois; December 10 to 12, 2002
   (hltp://duin.org/sludio/naplJ21002/)
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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
•  Internet Databases - In Situ Thermal
   Treatment (http://duin. org/products/thermal)
   and In Situ Chemical Oxidation
   (http://cluin.org/producls/chemox)

•  FRTR Cost and Performance Case Studies
   (http://www.frtr.gov/costperf)

•  State Coalition of Dry Cleaner Case Studies
   (http://www. drycleancoalition. org)

5.0  SUMMARY OF FINDINGS

The following general and technology-specific
findings about DNAPL characterization and
remediation are based on available information,
including data on the field technology
applications highlighted in this paper.

General Findings

Sites with DNAPL Contamination Have
Reached Regulatory Closure - Seven of the
eight sites have received closure letters (or the
equivalent) from regulators. These include  a
former electronics manufacturing facility, a
chemical manufacturing facility, a site where
film coating operations were performed, three
dry cleaner sites, and one MGP site.  Innovative
treatment technologies used at these seven sites
involved in situ thermal treatment (three sites), in
situ chemical oxidation (three sites), and in  situ
bioremediation (one site). Source removal was
used at some of the sites including removal  of
aboveground  storage tanks (Avery Dennison
Site, Illinois), and  soil excavation (Avery
Dennison Site, Illinois and  Arlington Cleaners,
Texas). The timespan from beginning use of in
situ treatment technology to receiving a closure
letter at these seven sites varied from 10 months
to about three years.

Sites with Ongoing Remedial Systems Have
Made Substantial Progress Toward Closure -
For the one site that has not yet reached closure
(King's Bay Naval Submarine Base (NSB),
Site 11, Georgia),  project contacts reported that
substantial progress toward closure is being
made and closure is expected in  the next 1 to 2
years. At this site,  injection of chemical oxidant
reduced contaminant levels in ground water to
below cleanup levels for most of the site;
monitoring is ongoing.

Closure Criteria Varied by Site - For the seven
sites that have received closure letters (or the
equivalent) from regulators, there have been
variations in the criteria applied and in the
concentrations achieved by the remedial systems.
Some examples of the criteria applied at the sites
that received closure letters include Tier III
cleanup criteria, which allow performance of
variable-scale risk assessment activities (Former
Manufacturing Facility, Illinois); Tier II
cleanup goals for industrial land use
(Confidential Chemical Manufacturing
Facility, Indiana); Tier I commercial/industrial
Class 3 risk-based exposure levels for TCE and
PCE in ground water and Tier I Protective
Concentration Levels in soil (Parkwood
Former Dry Cleaner Site, Texas); and
industrial cleanup objectives (Former MGP Site
(South California Edison [SCE]), California).

In the following cases, regulators have approved
risk-based site closure with significant
concentrations of contaminants left in place:

•  Former Manufacturing Facility, Illinois -
   State regulators  approved a closure goal for
   TCE of 17,500 ug/L using risk-based criteria
   under the state voluntary cleanup program.

•  Parkwood Former Dry Cleaner Site,
   Texas, and Arlington Cleaners, Texas -
   Risk-based cleanup goals for PCE and TCE in
   ground water were set at 500 ug/L at these
   sites.

Although Former MGP Site (SCE), California
reported site closure without restrictions, at other
sites, restrictions or conditions were placed on
closure. For example, the "No Further Action"
(NFA) letters obtained for the Avery Dennison
Site, Illinois and the Parkwood Former Dry
Cleaner Site, Texas required implementation of
institutional controls, and the NFA letter for
Former Manufacturing Facility, Illinois
required ongoing, passive, subsurface venting to
prevent soil vapors from entering  adjacent
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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
buildings. For the Former Cowboy Cleaners
Site, Colorado the NFA letter permitted only
commercial use.

Site Characterization Challenges Affected
DNAPL Remediation Performance - Because
of the difficulties with locating and quantifying
DNAPLs in contaminated media, it is difficult to
correctly design and operate a remedial system.

Partial Source Zone Removal Reduced the
Size of Residual Ground Water Plumes - The
effects of partial source zone removal on residual
ground water plumes were evaluated at some
sites with substantial reductions in residual
plumes observed over time.

•  King's Bay NSB, Site 11, Georgia - The
   source area was treated using a series of
   injections of Fenton's reagent followed by an
   injection of vegetable oil to facilitate
   bioremediation. Levels of total chlorinated
   hydrocarbons in the most contaminated area
   were reduced from nearly 200,000 ug/L in
   1999 to 120 ug/L in 2002.  U.S. Geological
   Survey (USGS) modeling supported by field
   data indicates that MNA  will completely
   clean up a residual plume of approximately
   100 ug/L total chlorinated hydrocarbons in
   approximately 3 years.

Technology-Specific Findings

Technology-specific findings are presented
below for use of in situ thermal treatment, in situ
chemical oxidation, and in situ bioremediation
for remediating DNAPL sources.

In Situ Thermal Treatment - The three
projects that used in situ  thermal treatment were
implemented at manufacturing facilities.  Two of
the  sites were treated using electrical resistive
heating and one was treated  using conductive
heating, with all operations performed at full
scale. The geology at these  sites was
heterogeneous, consisting of lower-permeability
soils.  These sites required use of between 27 and
185 electrodes or heater/vacuum wells. The
following three sites received closure letters after
less than one year of thermal treatment:
•  Former Manufacturing Facility, Illinois -
   Used an ERH system consisting of 185
   electrodes and 37 recovery wells to reduce
   TCE, 1,1,1-trichloroethane (TCA), and cis-
   1,2-dichloroethene (DCE) concentrations in
   ground water from more than 100,000 ug/L to
   less than state risk-based cleanup goals
   (17,500 ug/L for TCE, 8,850 ug/L for 1,1,1-
   TCA, and 25,500 ug/L for cis-l,2-DCE) in 10
   months.

•  Confidential Chemical Manufacturing
   Facility, Indiana - Used an in situ thermal
   conductive heating system consisting of 148
   heater/vacuum wells to reduce TCE, PCE,
   and 1,1-DCE concentrations in soil from more
   than 3,500 mg/kg to less than state risk-based
   cleanup goals for industrial land use (25
   mg/kg for TCE, 8 mg/kg for PCE, and 0.08
   mg/kg for 1,1-DCE) in five months.

•  Avery Dennison Site, Illinois - Used an
   ERH system consisting of 95 electrodes and
   34 recovery wells to reduce methylene
   chloride concentrations in soil from more than
   40,000 mg/kg to less than the state risk-based
   cleanup goal (24 mg/kg) in 11 months.

Generally, these projects showed that in situ
thermal treatment has remediated sites with
varying subsurface conditions in both the
saturated and unsaturated zones to satisfy
regulatory requirements.

In Situ Chemical Oxidation - The four projects
that used in situ chemical oxidation, all  at full
scale, involved a naval base, two dry cleaning
facilities, and a former MGP site. Two  of the
sites were treated at full scale using Fenton's
reagent injection, one with ozone and one with
permanganate. The geology at these sites ranged
from coarse-grained sands and gravel (Kings
Bay NSB, Site 11, Georgia) to stiff clay
(Cowboy Cleaners, Colorado). The projects
typically involved multiple (up to four)  phases of
chemical injection. Three of the four sites
received closure letters.

•  Parkwood Former Dry Cleaner Site, Texas
   - Used Fenton's reagent introduced  at four
   injection points  to  reduce PCE concentrations
December 2004

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
   in ground water from 2,900 ug/L to less than
   500 ug/L (the state risk-based cleanup goal)
   in approximately 2.5 years.

•  Former MGP Site (SCE), California -
   Used in situ ozonation to reduce total PAH
   concentrations in soil from 2,500 mg/kg to
   less than 1.4 mg/kg (the site-specific risk-
   based cleanup goal) in approximately three
   years.

•  Former Cowboy Cleaners Site, Colorado -
   Used potassium permanganate to reduce PCE
   concentrations in ground water from 1,900
   ug/L to 48 ug/L in approximately one year.

In Situ Bioremediation - In  situ bioremediation
(at full scale) was used at a dry cleaning facility.
Proprietary Hydrogen Release Compound
(HRC®) was injected to generate reductive
conditions in the contaminated area in order to
encourage reductive dechlorination of
contaminants. The geology at this site consisted
of low-permeability clayey silt underlain by
medium to dark gray shade. The project resulted
in a conditional certificate of completion for the
site from state regulators, requiring satisfactory
maintenance of post-response action care (such
as maintenance of engineering controls,
remediation systems and/or use of non-
permanent institutional controls.) At this site,
HRC® was injected at 45 borings over
approximately 11 months, and chlorinated
solvent contaminant (PCE, TCE, DCE, and VC)
concentrations in ground water were reduced
from as high as 7,300 ug/L to less than the risk-
based cleanup goals for the site (500 ug/L for
PCE and TCE; 7,000  ug/L for DCE; and 200
ug/L for VC).
    References

    General

    Freeze, Allan R., and David B. McWhorter.
    1997. A Framework for Assessing Risk
    Reduction Due to DNAPL Mass Removal from
    Low-Permeability Soils. Ground Water. Vol.
    35, No. 1.

    Illinois Environmental Protection Agency
    (IEPA).  2004. Fact Sheet.  Tiered Approach to
    Correction Action Objectives (TACO). On-Line
    Address:  http://www. epa.state.il. us/land/taco/l-
    introduction.html. Downloaded July 20, 2004.

    Illinois Administrative Code.  Title 35, Subtitle
    G, Chapter I, Subchapter f, Part 742:  Tiered
    Approach to Corrective Action Objectives.

    Interstate Technology Regulatory and Council
    (ITRC).  2004. Strategies for Monitoring the
    Performance of DNAPL Source Zone Remedies
    (DNAPLs-5).

    ITRC. 2003a.  Technology Overview: An
    Introduction to Characterizing Sites
    Contaminated with DNAPLs.

    Kram, Mark L., Arturo Keller, Joseph Rossabi,
    and Lome Everett. 2001. DNAPL
    Characterization Methods and Approaches, Part
    1: Performance Comparisons. Groundwater
    Monitoring and Remediation. Fall. Pages 109-
    123.

    National Research Council. 2003.
    Environmental Cleanup at Navy Facilities:
    Adaptive  Site Management. National Academy
    Press.

    National Research Council. 1997. Innovations
    in Ground Water and Soil Cleanup -  From
    Concept to Commercialization.  National
    Academy Press.
December 2004
10

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                                DNAPL Remediation: Selected Projects Approaching Regulatory Closure
Sale, Tom C., and David B. McWhorter. 2001.
Steady State Mass Transfer from Single-
Component Dense Nonaqueous Phase Liquids in
Uniform Flow Fields. Water Resources
Research. Vol. 37, No. 2.  Pages 393-404.

U.S. Environmental Protection Agency (EPA).
2004a. Site Characterization Technologies for
DNAPL Investigations. EPA 542 R-04-017.

EPA.  2002. Handbook of Groundwater
Protection and Cleanup Policies for RCRA
Corrective Action. EPA 530 F-01-021.

EPA.  1999a.  Groundwater Cleanup: Overview
of Operating Experience at 28 Sites.  EPA 542-
R-99-006. On-Line Address: http://clu-in.org.

EPA.  1999b. Use of Monitored Natural
Attenuation at Superfund, RCRA Corrective
Action, and Underground Storage Tank Sites.
Office of Solid Waste and Emergency Response
(OSWER) Directive 9200.4-17P.

EPA.  1997. Cleaning  Up the Nation's Waste
Sites:  Markets and Technology Trends (1996
Edition).  EPA542-R-96-005.

EPA.  1996. The Role of Cost in the Superfund
Remedy Selection Process. Publication 9200.3-
23FS. EPA540F-96/018.

EPA.  1993. Guidance for Evaluating the
Technical Impracticability of Ground Water
Restoration. OSWER Directive 9234.2-25.

EPA.  1992. Estimating Potential for
Occurrence of DNAPL at Superfund Sites.
OSWER Publication 9355.4-07FS. National
Technical Information Service (NTIS) Order
Number PB92-963338CDH.

In Situ Bioremediation
EPA.  2000. Engineered Approaches to In Situ
Bioremediation of Chlorinated Solvents:
Fundamentals and Field Applications. EPA
542-R-00-008.
    In Situ Chemical Oxidation
    Environmental Security Technology Certification
    Program (ESTCP).  1999.  Technology Status
    Review: In Situ Oxidation.

    ITRC. 2001. Technical and Regulatory
    Guidance for In Situ Chemical Oxidation of
    Contaminated Soil and Groundwater.
    In Situ Surfactant/Co-solvent Flushing

    ITRC. 2003b.  Technical and Regulatory
    Guidance for Surfactant/Co-solvent Flushing of
    DNAPL Source Zones.

    In Situ Thermal Treatment
    EPA. 2004b. In Situ Thermal Treatment of
    Chlorinated Solvents - Fundamentals and Field
    Applications. EPA 542-R-04-010. On-Line
    Address: http://cluin. org

    Zero Valent Iron Injection
    U.S. Department of the Navy.  2003.  Final Cost
    and Performance Report - Feroxsm Injection
    Technology Demonstration Parcel C, Remedial
    Unit C4, Hunters Point Shipyard, San
    Francisco, California, July 11, 2003.
    DS.A013.10177
           NOTICE AND DISCLAIMER

    Preparation of this report has been funded wholly
    or in part by the U.S. Environmental Protection
    Agency (EPA) under Contract Number 68-W-
    02-034. Mention of trade names or commercial
    products does not constitute endorsement or
    recommendation for use.

    A PDF version of this report is available for
    viewing or downloading from the Hazardous
    Waste Cleanup Information (CLUIN) system
    web site at .

    For more information regarding this report,
    contact Rich Steimle, EPA Office of Superfund
    Remediation and Technology Innovation, at
    (703) 603-7195 or steimle.richard@epa.gov.
December 2004
11

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                                                                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
                                          Table 2. Summary of Selected DNAPL Remediation Projects
Site Name,
Location, Vendor
Technology,
Period of Operation
Scale, Media,
Quantity Treated
Project Goals, Program
Contaminant Concentrations
(Before Treatment)
Contaminant
Concentrations
(After Treatment)
Project Status,
Comments
IN SITU THERMAL TREATMENT PROJECTS
Former Manufacturing
Facility,
Skokie, IL
CES
Confidential Chemical
Manufacturing
Facility,
Portland, IN
Terratherm
Avery Dennison Site,
Waukegan, IL
CES
Steam injection with
SVE, 1991 - 1998;
ERH (185 electrodes/
37 recovery wells),
6/1998 - 4/1999
In situ conductive
heating (148
heater/vacuum wells),
7/1997-12/1997
ERH (95 electrodes/
34 recovery wells),
12/1999-11/2000
Full-scale, soil and
GW, 23,000 ft2, 24 ft
deep
Full-scale, soil,
8,100ft2, 11-18 ft
deep
Full-scale, saturated
and unsaturated soil,
16,000yd3,
17,000 ft2', 24 ft deep
1,1,1-TC A -8,850 ug/L
TCE - 17,500 ug/L
cis-l,2-DCE- 35,500 ug/L
(IEPA Tier III), State
Voluntary Cleanup Program
PCE - 8 mg/kg
TCE - 25 mg/kg
1,1 -DCE- 0.08 mg/kg
(IDEM Tier II, Industrial
Land Use), State Voluntary
Cleanup Program
MC - 24 mg/kg
(IEPA TACO), State
Voluntary Cleanup Program
1,1,1-TCA- 150,000 ug/L
TCE - 130,000 ug/L
cis-l,2-DCE- 160,000 ug/L
(maximum in GW prior to
ERH)
Observed DNAPL
PCE - 3,500 mg/kg
TCE - 79 mg/kg
1,1 -DCE -0.65 mg/kg
Suspected DNAPL
MC - 40,000 mg/kg (maximum
in soil)
MC- 1,900 mg/kg
(average in soil)
Suspected DNAPL
All GW below Tier III
cleanup levels approved
by IEPA
PCE - 0.53 mg/kg
TCE - 0.02 mg/kg
(average in soil)
1,1-DCE-No
confirmation samples were
available
MC- 2.51 mg/kg
(average in soil)
IEPA NFA letter
(7/29/2002) requires
passive subsurface
venting
IDEM NFA letter
(Date not provided)
IEPA NFR letter
(4/2001) requires
institutional controls
IN SITU CHEMICAL OXIDATION PROJECTS
King's Bay NSB, Site
11, GA
GeoCleanse
Parkwood Former Dry
Cleaner, TX
IVI Environmental
Fenton's reagent
injection (23
injectors, 3 injection
phases),
11/1998-1/2002
Fenton's reagent with
surfactant (4 injection
points),
12/1998-5/2002
Full-scale, GW,
4,800 ft2,
30-40 ft deep
Full-scale, soil and
GW, 32,000 ft2
Total cVOCs - 100 ug/L
RCRA Corrective Action
Program
PCE - 5 mg/kg
TCE -3. 4 mg/kg
(TRRP Tier 1 PCL)
PCE - 500 ug/L
TCE - 500 ug/L
(TRRP Tier 1 C&I Class 3
GW REEL)
State Voluntary Cleanup
Program
PCE - 8,500 ug/L
TCE - 550 ug/L
DCE - 24 ug/L
(maximum in GW)
Suspected DNAPL
PCE - 47,350 mg/kg
TCE -1,500 mg/kg
(maximum in soil)
PCE - 2,900 ug/L
TCE - 320 ug/L
DCE - 900 ug/L
(maximum in GW)
Suspected DNAPL
TCEinGW
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                                                                                       DNAPL Remediation: Selected Projects Approaching Regulatory Closure
                                       Table 2.  Summary of Selected DNAPL Remediation Projects (continued)
Site Name,
Location, Vendor
Former MGP Site
(SCE), Long Beach,
CA
In-Situ Oxidative
Technologies
Former Cowboy
Cleaners Site,
Broomfield, CO
ESN Rocky Mountain
Technology,
Period of Operation
In situ ozonation,
1998 - 2001
Potassium
Permanganate
9/2001 - 8/2002
Scale, Media,
Quantity Treated
Full-scale, soil and
GW
Full-scale, soil and
GW, 29,000 ft2
Project Goals, Program
B(a)P-eq-1.75mg/kg
(Site-specific risk-based
cleanup level)
California DISC
Project goals not identified;
State Voluntary Cleanup
Program
Contaminant Concentrations
(Before Treatment)
Total PAH - 2,484 mg/kg
>100 mg/kg B(a)P-eq
(maximum in soil)
Suspected DNAPL
PCE -1,900 ug/L
(maximum in GW)
Suspected DNAPL
Contaminant
Concentrations
(After Treatment)
B(a)P-eq- 1.4 mg/kg
(average in soil)
PAH concentrations in
GW were reduced to ND
PCE - 48 ug/L
(source area)
Project Status,
Comments
Site was granted
closure by the
California DTSC
NFA letter issued by
State of Colorado
(2/2003), requires
commercial use
7N SITU BIOREMEDIATION PROJECTS
Arlington Cleaners,
TX
Regenesis
HRC® injected into
45 borings, 12/1999
-11/2000
Full-scale, soil and
GW, 3,500 ft2, 22 ft
deep
PCE - 500 ug/L
TCE - 500 ug/L
DCE - 7,000 ug/L
VC - 200 ug/L
(Target cleanup
concentrations based on
CEAM)
State Voluntary Cleanup
Program
PCE - 4,500 ug/L
TCE -1,000 ug/L
DCE - 7,300 ug/L
VC - 870 ug/L
(maximum in GW)
Suspected DNAPL
PCE - 408 ug/L
TCE - 87.4 ug/L
DCE - 438 ug/L
VC - 132 ug/L
(Average in GW)
Conditional COC
from the TCEQ
Voluntary Cleanup
Program
(10/26/2001).
Source: Project profiles in Appendix A
December 2004
13

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                                                                                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
        Notes:

        ug/L
        B(a)P-eq
        CEAM
        CES
        coc
        cVOC
        DCE
        DNAPL
        DISC
        EPA
        ERH
        ft
        ft2
        GW
        HRC®
        IDEM
Micrograms per liter
Benzo(a)pyrene equivalent                   IEPA
Center for Exposure Assessment Modeling      L
Current Environmental Solutions              MC
Certificate of completion                     MCL
Chlorinated Volatile Organic Compound       mg/kg
Dichloroethene                             MGP
Dense Nonaqueous-Phase Liquid              MNA
Department of Toxic Substances Control       ND
U.S. Environmental Protection Agency         NFA
Electrical Resistive Heating                   NFR
Foot                                      NPL
Square foot                                NSB
Ground water                              PAH
Hydrogen Release Compound                 PCE
Indiana Department of Environmental          REEL
Management                               RCRA
Illinois Environmental Protection Agency
Liter                                      SCE
Methylene chloride                          SVE
Maximum Contaminant Level (EPA)           TACO
Milligram per kilogram
Manufactured Gas Plant                     1,1,1 -TCA
Monitored natural attenuation                 TCE
Non-detectable                             TCEQ
No Further Action
No Further Remediation                     TRRP
National Priorities List                      VC
Naval Submarine Base                      yd3
Polycyclic Aromatic Hydrocarbon
 Tetrachloroethene
 Risk-Based Exposure Level
Resource Conservation and Recovery
Act
Southern California Edison
Soil Vapor Extraction
Tiered Approach to Correction Action
Objectives
Trichloroethane
Trichloroethene
Texas Commission on Environmental
Quality
Texas Risk Reduction Program
Vinyl chloride
Cubic yard
December 2004
                                                            14

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           Appendix A




DNAPL Remediation Project Profiles

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                                  DNAPL Remediation:  Selected Projects Approaching Regulatory Closure
Electrical Resistive Heating at Former
Manufacturing Facility, Skokie, Illinois
Site Name:

Site Location:
Technology Used:

Regulatory Program:

Remediation Scale:
Project Duration:
Former Manufacturing
Facility
Skokie, Illinois
Electrical Resistive
Heating (ERH)
Illinois Voluntary Site
Remediation Program
Full
1991 to 1999
Site Information: The site is a former
electronics manufacturing facility located in
Skokie, Illinois. Manufacturing at this location
began in  1958 and included machining,
electroplating, heat-treating, silk screening,
silicon chip production, and research and
development.  Trichloroethene (TCE) and 1,1,1-
trichloroethane (1,1,1-TCA) were feedstock
chemicals associated with various manufacturing
processes. By 1988, all processes had been
discontinued, and the facility was sold and
redeveloped.

Contaminants: Chlorinated solvents (TCE and
1,1,1-TCA, as well as degradation products cis-
and trans-1,2-dichloroethene [DCE], 1,1-DCE,
1,1-dichloroethane [DCA], vinyl chloride [VC],
and chloroethane); sampling indicated that dense
nonaqueous-phase liquids (DNAPL) were
present in clays at depths of five to eight feet
below ground surface (bgs), and in the soil pores
from the  water table (seven feet bgs) to depths of
18 to 20 feet bgs.  Concentrations in ground
water at the initiation of ERH for cis-l,2-DCE
were as high as 160,000 inicrograms per liter
(|j.g/L), for TCE as high as 130,000 ng/L, and for
1,1,1-TCA as high as 150,000 ng/L.

Hydrogeology: The facility overlies
heterogeneous silty sands with clay lenses to 18
feet bgs and has a hydraulic conductivity ranging
from 10"4 to 10"5 centimeters per second
(cm/sec). Below 18 feet bgs, a dense clay till or
ground moraine forms an aquitard with a
hydraulic conductivity of 10"8 cm/sec. Ground
water is encountered at seven feet bgs.
Project Goals: The following table shows the
Tier III cleanup criteria for ground water
proposed by the vendor and approved by Illinois
Environmental Protection Agency (IEPA) as the
cleanup goals for the site. According to lEPA's
Site Remediation Program guidelines, Tier III
allows conduct of variable-scale risk assessment
activities and more complex contaminant fate
and transport modeling than is allowed in more
stringent cleanup tiers.

 Cleanup Criteria for Former Manufacturing
      Facility, Skokie, Illinois (Tier III)
Contaminant
cis 1,2-DCE
1,1,1-TCA
TCE
Tier III Cleanup Level
for Ground water (jlg/L)
35,500
8,850
17,500
                              Cleanup Approach: From 1991 to 1998, steam
                              injection combined with ground water and vapor
                              extraction was used to clean up the site.  After
                              seven years of operation, the area of
                              contamination had been reduced from about
                              115,000 square feet to about 23,000 square feet.
                              As of early 1998, the remaining area to be
                              remediated represented four source locations
                              where artificial subsurface features limited the
                              effectiveness of the previously used steam-based
                              remediation system.

                              To complete the remediation, the site owner
                              employed an ERH system initially consisting of a
                              network of 107 electrodes, with 85 of the
                              electrodes constructed beneath the floor of a
                              warehouse building. After five months of
                              operation, the system was shut down for about 1
                              month, while 78 more electrodes were installed
                              (185 electrodes total). All electrodes were
                              designed to be electrically conductive throughout
                              a depth interval of 11 to 21 feet bgs and to
                              increase the subsurface temperature in the depth
                              interval of five to 24 feet bgs to the boiling point
                              of water. A network of 37 soil vapor extraction
                              wells, screened to five feet bgs, were used to
                              capture vapors. The off-gas system consisted of
                              a vacuum extraction blower and a steam
                              condenser.  The ERH process operated at the
                              Skokie site  from June 4, 1998 to April 30, 1999.
                                               A-l

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
Project Contacts:

William Heath, Current Environmental
Solutions, (509) 371-0905, bill@cesiweb.com

Stan Komperda, IEPA, (217) 782-5504,
epa4207 @ epa. state.il.us

Project Time Line:

1991-3/98      Steam injection and soil and
               ground water extraction
6/4/98         ERH system began operation
10/98          ERH system temporarily shut off
12/98          Additional ERH system began
               operation
4/30/99        System shut off and
               demobilization began
7/29/99        Illinois EPA issues a No Further
               Remediation letter
5/99 - 12/99    Post-remedial monitoring
               conducted

Project Results:  Tier III cleanup goals were
achieved for the three constituents of concern in
all seven monitoring wells. In addition,
contaminant concentrations in a number of wells
were reduced to more stringent Tier I cleanup
levels. For example, the Tier I cleanup level for
1,1,1-TCA was met in all seven wells, for cis-
1,2-DCE in one well, and for TCE in two wells.
The IEPA issued a letter on July 29, 1999
granting the site's request for a No Further
Action (NFA) determination with several
conditions and terms for the determination,
including installation of a passive ventilation
system (vent wells) to provide a preferential
pathway for vapors to migrate.  Two additional
rounds of ground water monitoring sampling
were performed following completion of ERH.
This monitoring showed that the concentrations
of TCE, 1,1,1-TCA, and cis-l,2-DCE were
remaining below the Tier III ground water
cleanup levels, and that contaminant
concentrations remained stable or continued to
decrease.
Source:

Federal Remediation Technology Roundtable.
2003. "Cost and Performance Report: Electrical
Resistive Heating at a Former Manufacturing
Facility, Skokie, Illinois."
http://costpeijbrmance.ors.
                                              A-2

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
In situ Conductive Heating at a Confidential
Chemical Manufacturing Facility, Portland,
Indiana
Site Name:

Site Location:
Technology Used:


Regulatory Program:

Remediation Scale:
Project Duration:
Confidential Chemical
Manufacturing Facility
Portland, Indiana
In situ Conductive
Heating (In situ Thermal
Desorption)
State Voluntary Cleanup
Program
Full
July to December 1997
Site Information:  The site is a 16-acre
chemical manufacturing facility located in the
southern portion of Portland, Indiana, southeast
of the Salmonie Puver. The site has operated
since 1886, initially as a lumberyard, then for
wheel manufacturing.  The site was used for the
manufacture of hard rubber products used in
automobiles and then for the manufacture of
plastic exterior automobile parts. The site has
four buildings including a north plant building
that is currently being used part-time for the
reworking of automotive parts. A sampling
event conducted in June 1994 revealed the
presence of volatile organic compounds (VOCs)
in soil and ground water. Additional
investigations performed from July 1995 to
February 1996 confirmed the presence of VOCs
in subsurface soils in two areas near the north
plant building. Contamination in one area
covered 150 feet by 50 feet to a depth of 18 feet,
and the contamination in the other extended to an
area of 30 feet by 20 feet to a depth of 11 feet.

Contaminants: Chlorinated solvents (PCE,
TCE and 1,1-DCE) were detected in the
unsaturated zone at levels up to 3,500 mg/kg, 79
mg/kg and 0.65 mg/kg, respectively.  The
elevated concentration of PCE suggested the
presence of DNAPL.  VOCs were not found
above the cleanup goals in  ground water after
treatment.
Hydrogeology: The facility overlies a
heterogeneous combination of fill, clayey sand
and construction debris, to a depth of about
seven feet.  Tills, consisting  of moist, silty clay
extend to a depth of 18 to 19 feet bgs.  Fine to
coarse gray sand with some gravel are found
beneath the till at depths greater than 19 feet and
extending to a maximum of 30 feet.  The
estimated hydraulic conductivity of this zone was
10"8 cm/sec.

Project Goals:  Soil cleanup goals were
established based on the Indiana Department of
Environmental Management (IDEM) Tier II
Cleanup Goals for Industrial Land Use.

 Cleanup Criteria for Confidential Chemical
  Manufacturing Facility, Portland, Indiana
                   (Tier II)
Contaminant
1,1 -DCE
TCE
PCE
Tier II Cleanup
Level for Soil
(mg/kg)
0.080
25
8
                             Cleanup Approach: Site investigations began
                             in 1994, and remedial activities began in 1997.
                             The in situ conductive heating system began
                             operation in July 1997 to treat the contaminated
                             soil in two source areas.  A total of 130
                             heater/vacuum wells were installed on a 7.5-foot
                             triangular spacing in the first area to a depth of
                             19 feet. The second area had 18 heater/vacuum
                             wells on a 7.5-foot triangular spacing to depths
                             of 12 feet. These wells were used to heat (1,400
                             - 1,600°F) the subsurface and to extract soil gas.
                             Off-gases were treated with a flameless thermal
                             oxidizer and were cooled by a heat exchanger,
                             then passed through a carbon adsorption bed.
                             Off-gases were monitored for hydrogen chloride,
                             which was used as an indicator of the
                             decomposition of chlorinated solvents. Off-gases
                             were treated with an 1800 standard cubic feet per
                             minute (scfm) flameless thermal oxidizer with an
                             operating temperature range of 1,800 - 1,900°F,
                             cooled by a heat exchanger, then passed through
                             a carbon adsorption bed.
                                              A-3

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
To determine the effectiveness of the treatment
system, about 50 soil samples were collected
from the coldest locations farthest from each
heater well and analyzed for VOCs. Based on
the results from soil samples, heating was
discontinued in December 1997.  Confirmation
sampling was conducted after monitoring the soil
temperatures for six months.

Project Contacts:

Ralph Baker, Ph.D. TerraTherm, Inc.,
rbaker@terrallierm.com.

Peggy Dorsey, Indiana Department of
Environmental Management (IDEM),
(317)234-0966
Project Time Line:

1994 - 1996    Site investigations performed

7/97 - 12/97    Remediation performed

Project Results: Results of confirmation
sampling after treatment showed that PCE and
TCE concentrations were below the cleanup
goals. No confirmation samples were available
for the smaller, 1,1-DCE contaminated zone
area. The following table shows contaminant
concentrations at locations that had relatively
higher concentrations before treatment. Based
on the results, the IDEM issued a No Further
Action (NFA) letter for this property.
Information about the date or conditions of the
NFA letter was not provided.
        Comparison of Selected Pre-Heating and Post-Heating Contaminant Concentrations
Sampling Location
SA13
GP31
SA4
SB 20
SB 19
Depth
(feet)
9-10
15-16
4-5
4-5
12-14
Contaminant Concentration (mg/kg)
Before Treatment
PCE
3,500
570
23
2.9
76
TCE
79
Not sampled
0.25
0.67
1.6
After Treatment
PCE
0.011
0.18
0.530
0.046
0.048
TCE
0.020
0.008
ND
ND
ND
ND - non-detect (detection limits not provided)

Source:

Federal Remediation Technology Roundtable.
2003. "Cost and Performance Report: In situ
Conductive Heating at the Confidential Chemical
Manufacturing Facility, Portland, Indiana."
hlW://cosWerfonnance.ors.
                                              A-4

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
Electrical Resistive Heating at the Avery
Dennison Site, Waukegan, Illinois
Site Name:
Site Location:

Technology Used:

Regulatory Program:

Remediation Scale:
Project Duration:
Avery Dennison Site
Waukegan-Gurnee
Industrial Park, Illinois
Electrical Resistive
Heating (ERH)
Illinois EPA Site
Remediation Program
Full
December 1999 to
November 2000
Site Information: The site is located in the
Waukegan-Gurnee Industrial Park in Waukegan,
Illinois. Film coating operations were performed
at this site from 1975 through 1992.  Methylene
chloride (MC) was used in these operations, and
was transferred to above-ground storage tanks
via underground piping.  Site investigations
showed the occurrence of MC in the soil and
ground water in several areas at the  site.

Contaminants: Approximately 17,000 square
feet of soil along the north side of the building
on the site was contaminated with MC to depths
as great as 24 feet bgs, with concentrations as
high as 40,000 mg/kg. MC  concentrations in the
soil in this area averaged 1,900 mg/kg.
Information about the concentration of MC in
ground water was not provided.

Hydrogeology: The underlying geology at the
site is predominantly heterogeneous silty-clay,
glacial till to a depth of about 180 feet bgs.
Depth to ground water varies from six feet to 25
feet bgs.  Bedrock is encountered at depths
ranging from 180 feet to 270 feet bgs.

Project Goals: The remediation objective was
to reduce the concentration of MC in the soil to
below 24 mg/kg, based on lEPA's Tiered
Approach to Corrective Action Objectives
(TACO).

Cleanup Approach: The treatment area was
divided into 20 treatment cells. For each
treatment cell,  electrodes were installed around
the perimeter to a depth of 24 feet. A total of 95
copper electrodes were installed including six
installed below an active street, and 16 installed
inside the existing building. Two thermocouples
were installed in the center of each treatment
cell, at the shallowest and deepest levels of
contamination, four and 24 feet bgs.  In addition,
34 recovery wells were installed at 20 locations
to extract soil vapor and steam. The designed
power input was 610 kilowatts (kW).  The
treatment system was expected to raise soil
temperatures at a rate of at least 1°C per day until
a temperature above 75 °C was achieved.

Project Contacts:

Chris Thomas, Current Environmental Solutions,
(847) 298-2764, chris@cesiweb.com

Jennifer Seul, Illinois Environmental Protection
Agency, (217)785-9399,
jennifer.seul@epa.state.il.us

Project Time Line:

1985           Removal Action
1988           Installation of grout curtain
               around the former bulk storage
               area
1991 -1994     Soil vapor extraction performed
               at former bulk storage area.
               This was ineffective and
               discontinued at the end of 1994.
1992-1994     Pump and treat of ground water
1994-1998     Air sparging of ground water
12/99          ERH initiated in western portion
6/00           ERH initiated in eastern portion
11/00          ERH completed
4/01           IEPA issued NFR letter

Project Results: A total of 125 soil samples
were collected and  analyzed for MC. Average
MC concentrations in soil were reduced to 2.51
mg/kg, below the cleanup goal. Based on the
results of the confirmatory samples, the IEPA
issued a No Further Remediation (NFR) letter for
this property in April 2001, which specified
several engineering and institutional controls,
including a prohibition on the installation and
use of potable water supply wells in a specified
area around the site.
                                              A-5

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                                  DNAPL Remediation: Selected Projects Approaching Regulatory Closure
Source:
Federal Remediation Technology Roundtable.
2003.  "Cost and Performance Report: Electrical
Resistive Heating at the Avery Dennison Site,
Waukegan, Illinois."
http://costperformance.ors.
                                               A-6

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                                 DNAPL Remediation:  Selected Projects Approaching Regulatory Closure
In Situ Chemical Oxidation at the Kings Bay
Naval Submarine Base (NSB). Site 11.
Georgia
Site Name:
Site Location:

Technology Used:
Regulatory Program:

Remediation Scale:
Project Duration:
Kings Bay NSB, Site 11
Old Camden County,
Georgia
In situ Chemical
Oxidation (Fenton's
Reagent)
RCRA Corrective
Action
Full
November 1998 to
January 2002
Site Information:  The site is a former landfill
used for disposal of municipal waste during the
mid-1970s to 1980.  It encompasses an area of
25 acres in Camden County in southeastern
Georgia.  PCE was disposed in the landfill,
resulting in ground water contamination with
PCE and degradation products TCE, cis-1,2-
DCE, and VC. Site investigations indicated that
the extent of contaminant was 120 feet long by
40 feet wide and at a depth of 30 to 40 feet bgs.
The treatment area was estimated to consist of
approximately 3,000 tons of contaminated soil
and 80,000 gallons of contaminated ground
water.  Remedial activities began in the early
1990s.

Contaminants:  Chlorinated solvents (PCE,
TCE and cis-l,2-DCE); the maximum
concentrations of contaminants were 8,500 |ig/L
for PCE, 550 ng/L for TCE, and 24 ng/L for cis-
1,2-DCE in ground water.

Hydrogeology:  The site geology is
characterized as fine to medium quartz sand
interbedded with silty and/or clayey sands.
Ground water is encountered at six feet bgs. An
unconfined surficial aquifer is approximately 90
feet thick in the vicinity of the landfill.
Hydraulic conductivity is reported as  30 feet/day
in the 30- to 40-foot depth interval.
Project Goals:  The remediation objective was
to reduce the concentration of total chlorinated
aliphatic compounds (CAC) in the ground water
to 100 |ig/L, based on natural attenuation
modeling of the downgradient plume.

Cleanup Approach: Treatment operations
began in November 1998 with installation of 23
specially designed injectors in and around the
area of concern. During Phase 1, a total of 8,257
gallons of Fenton's reagent (an elemental
iron/hydrogen peroxide slurry) were injected
over a 19-day period, followed by Phase 2, with
the injection of an additional 3,788 gallons over
a 7-day period in June and July 1999. Ground
water samples were collected before, during  and
after both phases of treatment from seven
monitoring wells and two ground water recovery
wells. Phase 1 treatment focused on the central
part of the contaminant plume, while Phase 2
focused on the downgradient areas that were not
treated in Phase 1. Following Phase 2, elevated
CAC concentrations (1,700 |ig/L) were detected
near injector 1-14,  indicating the presence of a
previously unidentified contamination source
area. Further treatment of this area was
performed during Phase 3 of remediation, which
included injection of additional chemical oxidant
as well as additives (including a vegetable oil) to
enhance biodegradation. Specific materials  and
quantities injected in Phase 3 were not identified.

Project Contacts:

Clifton C. Casey, Southern Division, NAVFAC
Environmental Department (843) 820-7422,
caseycc@efdsouth.navfac.navy.mil

Mary Brown, Georgia Department of Natural
Resources, Mary Brown@dnr.state.ga.us

Project Time Line:

11/98-2/99     Phase  1 treatment performed
6/99-7/99      Phase 2 treatment performed
7/99-1/02      Phase 3 treatment performed
                                              A-7

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                                 DNAPL Remediation:  Selected Projects Approaching Regulatory Closure
Project Results: The contaminated area was
treated in a series of injections of Fenton's
reagent, followed by an injection of vegetable oil
to help support biodegradation. Levels of total
chlorinated hydrocarbons in the most
contaminated area have been reduced from
nearly 200,000 ug/L in 1999 to 120 |ig/L in
2002 and currently range from <1 to 13.9 ug/L.

USGS modeling, supported by field data,
indicate that at a level of approximately 100 |ig/L
total chlorinated hydrocarbons, monitored natural
attenuation at the site will complete cleanup of
the plume in approximately three years. As of
May 2003, there were no longer any exceedences
of MCLs in any of the off-site monitoring wells,
and most of the on-site monitoring wells have
had no measurable levels of contaminants.  The
cleanup goal of 100 |ig/L has been  successfully
met.
Sources:

Federal Remediation Technology Roundtable.
2000. Cost and Performance Summary Report:
"In Situ Chemical Oxidation Using Fenton's
Reagent at Naval Submarine Base Kings Bay,
Site 11, Camden County, Georgia."

Mary Brown, Georgia Department of Natural
Resources.  July 2, 2003. E-mail to Richard
Weisman, Tetra Tech EM Inc. Status of Kings
BayNSB, Site 11  Cleanup.

Mary Brown, Georgia Department of Natural
Resources.  May 14, 2004.  E-mail to Raji
Ganguli, Tetra Tech EM Inc.  Update on ISCO at
Kings Bay NSB, Site  11, Georgia.
                                              A-8

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
In Situ Chemical Oxidation at the Parkwood
Former Dry Cleaner Site, Piano, Texas
Site Name:

Site Location:
Technology Used:
Regulatory Program:
Remediation Scale:
Project Duration:
Parkwood Former Dry
Cleaner Site
Piano, TX
In situ Chemical
Oxidation (Fenton's
reagent)
Texas Commission on
Environmental Quality
(TCEQ) Voluntary
Cleanup Program
Full
December 1998 to May
2002
Site Information:  The site is a former dry
cleaner facility located in Piano, Texas.

Contaminants: Chlorinated solvents (PCE and
TCE); Maximum initial concentrations were
2,900 ug/L for PCE, 320 ug/L for TCE, and 900
ug/L for cis-l,2-DCE in ground water. After
monitoring well installation, soil samples showed
maximum initial PCE concentrations of 10,000
jig/kg to 47,000 |ig/kg at one to five feet bgs, and
a TCE concentration of 1,500 |ig/kg at six feet
bgs.

Hydrogeology: The site soils consist of black or
brown clay, medium to fine gravel, and traces of
coarse to fine sand from the surface to  18 feet
bgs. The vertical limits of the contaminant
ground water plume were found at the top of the
Austin Chalk bedrock, located 16 feet to 18 feet
bgs.

Project Goals: The remediation objective was
to reduce the concentration of chlorinated
hydrocarbons in the soil to Texas Risk Reduction
Program (TRRP) Tier 1 Commercial/Industrial
Class 3 Ground water Risk-Based Exposure
Level (REEL) (500 ug/L for both PCE and TCE)
and soil to the TRRP Tier 1 Protective
Concentration levels (PCLs) (5 mg/kg PCE and
3.4mg/kgforTCE).
Cleanup Approach: The approximate area of
contamination was 0.74 acre. Remediation
activities included installation of four in situ
chemical oxidation injection points used to inject
Fenton's reagent as well as a proprietary
surfactant. Information about the type of
surfactant used or the quantities injected were
not provided. For post-remediation monitoring,
four soil borings were advanced and post-
remediation ground water sampling was
conducted as well. Based on the January 2001
post-remediation sampling event, the
concentration of total VOCs in ground water had
been reduced by 83.2 percent to 100 percent with
an average of 94 percent.

Project Contacts:

David R. Lent, CPG, IVI Environmental, Inc.,
(914) 694-9600

Merrie Smith, TCEQ, (512)  239-1000

Project Time Line:

1/00-11/00     Conducted in-situ chemical
               oxidation activities
2001           Conducted 3 rounds of post-
               remediation ground water
               sampling
11/02          Certificate of completion letter
               issued by TCEQ

Project Results: Three post-remediation ground
water-sampling events indicated that no
contaminants were found above their respective
standard in any of the monitoring wells. Final
concentrations detected are listed as follows:
300 ug/L PCE, 52 ug/L TCE, and 91 ug/L cis-
1,2-DCE. A certificate of completion letter was
issued by TCEQ, stating that the property is
suitable for non-residential use and does not
require maintenance of engineering controls,
remediation systems, post closure care,
permanent institutional controls or non-
permanent institutional controls.  The COC
required the implementation of deed restrictions
to ensure only non-residential use of the
property.
                                              A-9

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
Sources:
IVI Environmental, Inc. 2002. Ground water
Monitoring Report.

Texas Commission on Environmental Quality.
2002. Voluntary Cleanup Program Final
Certificate of Completion.
                                             A-10

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                                 DNAPL Remediation:  Selected Projects Approaching Regulatory Closure
In Site Chemical Oxidation at Former
Southern California Edison (SCE)
Manufactured Gas Plant (MGP) Site, Long
Beach, California
Site Name:

Site Location:
Technology Used:


Regulatory Program:
Remediation Scale:
Project Duration:
Former MGP Site, Long
Beach, California
Long Beach, CA
In situ Chemical
Oxidation (Fenton's
Reagent and Ozonation)
California Department
of Toxic Substances
Control (DTSC)
Pilot and Full
1998 to 2003
Site Information:  The site was used from 1902
to 1913 to produce gas from oil and coal.  These
processes resulted in soil and ground water
contamination with PAH and total petroleum
hydrocarbons (TPH).

Contaminants: Initial concentrations of
contaminants were 2,484 mg/kg total PAH and
27,800 mg/kg TPH.  The chemicals of potential
concern identified for soil included seven
carcinogenic PAHs and nine noncarcinogenic
PAHs, as well as TPH.  A benzo(a)pyrene
equivalent (B(a)P-eq) value was calculated for
each carcinogenic PAH and summed together to
estimate the total B(a)P-eq concentration.  Prior
to treatment, B(a)P-eq in soil was slightly higher
than 100 mg/kg.

Hydrogeology: The site soils consist of fill
material overlying poorly sorted medium to fine
grain sand. The water table is located at
approximately ten feet bgs.

Project Goals:  The remedial strategy was to
clean up soil to meet an industrial cleanup
objective of 1.75 mg/kg B(a)P-eq.

Cleanup Approach:  The cleanup included a
pilot study using Fenton's chemistry and a full-
scale use of in situ ozonation.  A system of
injection wells and direct-push points was used.
Injections were made during 3-four day periods
and events were conducted 3 weeks apart. An
in-situ ozonation system was operated in
December 1998 to test the basic operation of the
system components and to determine the
subsurface flow characteristics prior to ozone
injection. Ozone generation was initiated in
January 1999 and continued until January 2001,
when the system was shut down. During the
operation of the system, 19,100 pounds of ozone
and 280,000 pounds of oxygen were generated
and injected.

Project Contacts:

Chris Nelson, In-Situ Oxidative Technologies,
(303) 843-9079

Mike Vivas, California DTSC, (916) 255-3727

Project Time Line:

10/98-11/98    In-situ ozonation system
               constructed
12/98          Initial oxygen sparging
               conducted
1999-2003      Ozone generation conducted

Project Results: Site-wide concentrations were
reduced from more than 100 mg/kg to 1.4 mg/kg
of B(a)P-eq. PAH and TPH concentrations in
ground water were reduced to non-detect levels
after the first injection. Final post remediation
contaminant concentrations in soil were not
available. The site vendor reported that the site
was granted closure by the California DTSC.

Sources:

In-Situ Oxidative Technologies, Inc. Case
Study: Former MGP Site.

Southern California Edison. Not Dated.
Remedial Action Report, Long Beach Former
MGP site (excerpts).
                                             A-ll

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
In Site Chemical Oxidation at Former
Cowboy Cleaners Site, Broomfield, Colorado
Site Name:

Site Location:
Technology Used:
Regulatory Program:

Remediation Scale:
Project Duration:
Former Cowboy
Cleaners Site
Broomfield, Colorado
In Situ Chemical
Oxidation
(permanganate)
Colorado Voluntary
Cleanup Program
Full
2001 to 2002
Site Information:  The site is a former dry
cleaning facility located near Denver, Colorado.
A site investigation revealed the presence of soil
and ground water contamination, with a ground
water plume covering approximately 1.5 acres.
The remediation was handled under the Colorado
Voluntary Cleanup Program. The plume
occupied portions of five separately owned
properties and crossed a street. Small portions of
the plume also flowed beneath a retail building
and a residence. The State of Colorado
determined that the low risks to potential
receptors justified a remediation of the source
area (soil), allowing the ground water to clean up
naturally over time.

Contaminants: Ground water at the site is
contaminated with PCE.  Maximum initial
concentration of PCE was 1,900 ug/L (suspected
DNAPL).

Hydrogeology: Depth to ground water at the
site is 25 bgs. The  site consists of stiff clay to
silty (sometimes sandy) clay at 3 ft bgs and a
sandy clay layer at 8 ft bgs.

Project Goals:  Cleanup goals not identified

Cleanup Approach: A system of 12 nested
injectors was installed in the source area. Semi-
permanent injectors manufactured using 1" PVC
screen and riser were installed to allow the
controlled injection of permanganate reagent
directly into the area of contamination. Each
injector was installed with a sand pack to just
above the screen, and grouted to the surface.
Upon setting of the grout, a charge of
permanganate was pressure injected into each
injector. A 10% by weight solution of
permanganate was introduced into each injector,
with as much volume as each injector would
take, to a maximum of 100 gallons.  The
injectors were then connected to each other in
ranks, and to a head tank by PVC piping. The
gravity feeding to all of the injectors on a
continuous basis was then started. Each injector
was equipped with valves to control flow, and
the system was kept in balance for about four to
five months. Up to 300 gallons per day of 1-2%
solution were fed into the system during
remediation.

Most of the injectors were completely above the
water table to avoid drainage of reagent directly
into ground water without extensive soil contact.
To control PCE that was mobilized into ground
water from the soil source area, aline of injectors
(curtain wall) was installed down stream. These
injectors were operated at very low volumes, and
controlled based on the results of a monitoring
well immediately downgradient.

Project Contacts:

James H. Viellenave, ESN Rocky Mountain,
(303) 278-1911. jviellenave@esn-rm.com

Mark Walker, Colorado Department of Public
Health and Environment, (303) 692-3449,
mark, walker @state.co.us

Project Time Line:
                             09/01
                             01/02
                             08/02

                             02/03
               Application of permanganate
               Post-treatment monitoring
               Post-treatment monitoring
               concluded
               No Action Determination letter
               issued by Colorado Department
               of Public Health and
               Environment
                                             A-12

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                                 DNAPL Remediation:  Selected Projects Approaching Regulatory Closure
Project Results: In the source area, PCE
concentration started at 1,900 ug/L.  One month
into the remediation process, PCE concentration
had dropped to 926 ug/L and continued to
decrease further to 284 ug/L three months after
initiation of the remedy. Post-remediation PCE
concentration, monitored 8 months later, was
found to be 48 ug/L. Downgradient PCE
concentrations decreased from 40 ug/L to 15
ug/L within a year.

In February 2003, the State of Colorado issued a
No Action Determination Approval, stating that
the property could be used for commercial
purposes, and did not pose an unacceptable risk
to human health and the environment.

Sources:

Colorado Department of Public Health and
Environment. 2003. No Action Determination
Approval.

James Viellenave. December 16, 2003. E-mail
to Raji Ganguli, Tetra Tech EM Inc providing
information on the Former Cowboy Cleaners Site
in Broomfield, Colorado.

Viellenave, J.H., J.P. Lauer,  and J.V. Fontana.
2002. Using Risk Based Cleanup Goals for In
Situ Chemical Oxidation of PCE in Vadose Zone
Soils Under a Voluntary Cleanup Program.
Paper presented at IPEC 2002. On-line address:
http://ipec. utulsa.edu/Ipec/Conf2002/tech sessio
ns.himl.
                                             A-13

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
In situ Bioremediation Using HRC  at a
Arlington Cleaners, Arlington, Texas
Site Name:
Site Location:
Technology Used:

Regulatory Program:
Remediation Scale:
Project Duration:
Dry Cleaning Facility
Arlington, Texas
In situ Bioremediation
Using HRC®
Texas Commission on
Environmental Quality
(TCEQ) Voluntary
Cleanup Program
Full
December 1999 to
November 2000
Site Information:  The site is located in
Arlington, Texas, covering approximately seven
acres. A former dry cleaner was situated in a
small suite and operated at the site between 1982
and 1992.  Environmental site assessments were
conducted in 1996 and the site was admitted into
the TCEQ Voluntary Cleanup Program. An
unknown amount of chlorinated solvents was
released at the site and had contaminated soil and
ground water. The concentrations of
contaminants of concern (COC) in subsurface
soils at a depth of approximately eight feet below
the building were in excess of site target
concentrations.  Site investigations revealed that
the ground water with COC concentrations above
the site target levels occupied approximately
3,500 square feet directly beneath and
downgradient of the source area.

Contaminants: Chlorinated solvents (PCE,
TCE, cis-l,2-DCE, and VC). Immediately prior
to injection of HRC®, the ground water
concentrations of COCs were 4,500 |ig/L for
PCE, 1,000 n.g/L for TCE, 7,300 |ig/L  for cis-
1,2-DCE, and 870 ug/L for VC.

Hydrogeology: The underlying rock at the site
is predominantly medium to dark gray shale,
which readily weathers to a thick, clayey soil.
Two TCEQ-designated aquifers exist beneath the
site. Site geology consists of a very low
permeability light to dark brown, soft, moist clay
from the ground surface to approximately 22 feet
bgs. Ground water is encountered at 7 feet bgs.
Project Goals:  The following table shows the
target cleanup concentrations at the site,
established by Conceptual Environmental
Assessment Model (CEAM), a health-based risk
assessment for ground water.

 Cleanup Criteria for Dry Cleaning Facility,
              Arlington, Texas
Contaminant
PCE
TCE
cis-l,2-DCE
VC
CEAM Cleanup Criteria
for Ground water (M-g/L)
500
500
7,000
200
                             Cleanup Approach: The cleanup approach
                             included soil excavation from the source area,
                             performed in 1998, followed by in situ
                             bioremediation using HRC® in 2002.  In May
                             2000, HRC® was injected into 45 borings that
                             are located within the shallow aquifer area to a
                             depth of approximately 22 feet bgs. Of the 45
                             injection borings, 29 borings were advanced
                             perpendicular to the ground surface, and 16
                             borings were advanced at angles of 15 to 30
                             degrees from vertical to extend beneath the
                             building's foundation.  A total of approximately
                             7,000 pounds of HRC® were injected at the rate
                             of 10.37 Ib/foot.  Quarterly sampling of ground
                             water was conducted as a part of the response
                             action.

                             Project Contacts:

                             Rick Gillespie, Regenesis Inc., (972) 377-7288,
                             rick@regenesis.com.

                             Jacqueline Hardee, P.E.,  Director Remediation
                             Division, TCEQ

                             Project Time Line:
                             1998
                             5/00
                             10/01
               Soil Excavation
               HRC® Injection
               Conditional Certificate of
               Completion issued by TCEQ
                                             A-14

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                                 DNAPL Remediation: Selected Projects Approaching Regulatory Closure
Project Results: Approximately 18 months
after HRC injection, PCE, TCE, cis-l,2-DCE,
and VC in the monitoring well located nearest to
the contaminant source area had decreased to
408 ng/L, 87.4 ng/L, 438 ng/L, and 132 ng/L,
respectively. Based on these results, the site
received a Conditional Certificate of Completion
from the TCEQ Voluntary Cleanup Program on
October 26, 2001.

Sources:

Koenigsberg, Stephen  S. (Ed). 2002.  "Case
Study: Dry Cleaning Facility, Arlington, TX."
In:  Accelerated Bioremediation with Slow
Release Electron Donors and Electron Acceptors
- Selected Battelle Conference Papers 2001-
2002.

Rick Railsback, Hardy, Shawn G., and Rick
Gillespie.  2002.  "Enhanced Reductive
Dechlorination Results in Conditional Closure at
Texas Dry Cleaner Facility." Battelle Press.

Texas Commission on  Environmental Quality
(TCEQ). 2001. Voluntary Cleanup Program
Conditional Certificate of Completion.
                                              A-15

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                 Appendix B

Suspected DNAPL Thresholds Based On Solubility
  Relative to One Percent of Aqueous Solubility

-------
                                DNAPL Remediation: Selected Projects Approaching Regulatory Closure
                                         Appendix B

                            Suspected DNAPL Thresholds Based on
                      Solubility Relative to 1 Percent of Aqueous Solubility
Chlorinated Solvent (CAS Number)
PCE (127-18-4)
TCE (79-01-6)
cis-l,2-DCE (156-59-2)
trans-l,2-DCE (156-60-5)
1,1-DCE (75-35-4)
Vinyl Chloride (75-01-4)
1,1,1-TCA (71-55-6)
1,1,2-TCA (79-00-5)
1,2-DCA (107-06-2)
1,1-DCA (75-34-3)
Chloroethane (75-00-3)
Carbon Tetrachloride (56-23-5)
Chloroform (67-66-3)
Methylene Chloride (75-09-2)
Chloromethane (74-87-3)
Aqueous Solubility
(ug/L @ 25 T)
200,000
1,472,000
3,500,000
6,300,000
2,250,000
8,800,000
1,334,000
4,420,000
8,524,000 1
5,057,000
5,678,000 1
793,000
7,920,000
1,030,000
5,325,000
1 % of Aqueous Solubility
(ug/L @ 25 T)
2,000
14,720
35,000
63,000
22,500
88,000
13,340
44,200
85,240
50,570
56,780
7,930
79,200
10,300
53,250
Notes:

    1.  The reference temperature is 20* C for the properties of these compounds.

    2.  Source for Aqueous Solubility: EPA. 2004.  In Situ Thermal Treatment of Chlorinated Solvents
       Fundamentals and Field Applications. EPA 542-R-04-010.

    3.  Source for 1 Percent Rule-of-Thumb: EPA. 1992. Estimating Potential for Occurrence of
       DNAPL at Superfund Sites.  OSWER Publication 9355.4-07FS. NTIS Order Number PB92-
       963338CDH.

    4.  DCA  Dichloroethane
       DCE  Dichloroethene
       PCE   Tetrachloroethene
       TCA  Trichloroethane
       TCE   Trichloroethene
                                             B-l

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              Appendix C




Examples of Treatment Technology Providers

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                                DNAPL Remediation: Selected Projects Approaching Regulatory Closure


                                         Appendix C

                         Examples of Treatment Technology Providers
In Situ Thermal Treatment Providers

Current Environmental Solutions
http://www. cesiweb. com

Integrated Water Resources
http://www. integratedwater. com

McMillan-McGee
http://www.mcmillan-mcgee.com

SteamTech Environmental Services, Inc.
http://www.steamtech.com

TerraTherm Environmental Services, Inc.
http://www. terratherm. com

Terra Vac
http ://www. terravac. com

Thermal Remediation Services, Inc.
htlp://www. ihermalrs. com
In Situ Chemical Oxidation Providers

Cleanox - The C3 Group
http://www. c3 group, com

Environmental Business Solutions International
(EBSI)
http://www. ebsi-inc. com

ESN Rocky Mountain
http ://www. esn-rm. com

Geo-Cleanse International Inc.
http://www.geocleanse.com

In-Situ Oxidative Technologies
http://www. insituoxidation. com

Kerfoot Technologies Inc. (formerly K-V
Associates)
http://www.kva-equipment.com

Xpert Design and Diagnostics (XDD)
http://www.xdd-llc. com
Surfactant/Co-solvent Flushing Providers

Surbec Environmental, LLC
http://www.surbec-an.com
In Situ Bioremediation Providers

Arcadis
http://www.arcadis-us. com

Golder Associates
http://www.golder. com

North Wind Inc.
http://www.nwindenv. com

Regenesis
http://ww.~w. regenesis. com

Solutions Industrial & Environmental Services
(IBS)
http://www.solutions-ies.com
Zero Valent Iron Providers

ARS Technologies
http://www.arstechnologies. com
Sources:

1.   EPA REmediation And CHaracterization
    Innovative Technologies (REACH IT)
    http://www. epareachit. org

2.   In Situ Chemical Oxidation Site Profiles
    http://www. cluin. org/products/chemox

3.   In Situ Thermal Treatment Site Profiles
    http://www. cluin. org/products/thermal
                                             C-l

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