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Tl
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/A newsletter about soil, sediment, and groundwater characterization and remediation technologies
Issue 45
7)zw mt/e o/Technology News and Trends highlights innovative strategies for in-situ treatment of
contaminated groundwater through subsurface injection of reagents to promote chemical oxida-
tion (chem/ox) or biodegradation through enhanced reductive chlorination of contaminants.
Sequential In-Situ Chem/Ox and ERD Treatment of
Groundwater Destroys CVOCs
Five chlorinated volatile organic compound
(CVOC) plumes originate from sources
beneath degreasing areas at the former Pall
Aeropower facility in Pinellas Park, FL.
Chemical oxidants in the form of Fenton's
reagent and potassium permanganate
(KMnO4) and emulsified soybean oil as an
electron donor were sequentially injected
into the saturated zone to directly destroy
contaminants and biodegrade them through
enhanced reductive chlorination (ERD).
After five years of injections and associated
groundwater conditioning, monitoring of
continuing source area ERD and plume
attenuation continues.
Chloroethenes used at the site from 1972 to
1998 were the most abundant and
widespread contaminants. Pre-remedial
sampling detected trichloroethene (TCE)
concentrations as high as 470,000 (Ig/L and
tetrachloroethene (PCE) concentrations as
high as 110,000 (Ig/L. Based on chemical
solubilities, dense non-aqueous phase liquid
(DNAPL) was suspected at four locations.
The PCE and TCE daughter compounds cis-
1,2-dichloroethene (cDCE) and vinyl chloride
and eight additional VOCs also were present.
Numerous physical and chemical challenges
were considered during remedy selection and
design. For example, site soil varies
considerably with depth. The upper 30-foot
surficial aquifer consists of fine silica sand
overlying silty, fine silica sand. A two-foot
layer of clay and silt separates the upper silica
soils from an underlying intermediate
confining unit—layers of silty sand, bioclastic
sand, and silt and clay that contain decomposed
limestone and shell fragments extending to
100 feet below ground surface (bgs).
Varying flow rates of groundwater, which is
encountered 3-4 feet bgs, also complicated
the treatment strategy. Low hydraulic
conductivity limits the annual groundwater
movement to 8 ft/yr at 11-16 feet bgs, 2 ft/yr
at 21-26 feet bgs, 10 ft/yr at 39-44 feet bgs,
and 0.25 ft/yr at 65-70 feet bgs. Another
challenge was the range of pH in background
groundwater, which is around 5.5 in the
surficial aquifer and between 7 and 8 in the
intermediate aquifer.
The majority of CVOCs were found in the
lower surficial aquifer (20-28 ft bgs, with
groundwater flow rate of 2 ft/yr), where low
hydraulic conductivity limits the recovery of
groundwater and distribution of injected
reagent solutions. Smaller quantities of
CVOCs in the upper surficial aquifer (over 20
ft bgs, with 8 ft/yr)) and in the upper
intermediate aquifer (30-50 ft bgs, 10 ft/yr)
also required treatment.
The treatment strategy focused on in-situ
destruction of DNAPL and the high
concentrations of dissolved-phase CVOCs,
which would most cost-effectively destroy
contaminant mass and decrease dissolved-
phase loading to the plumes. Natural
attenuation is anticipated to reduce the sizes
and concentrations of the plumes over time.
Chem/ox using Fenton's reagent was the first
technology implemented based on its ability
[continued on page 2]
December 2009
Contents
Sequential In-Situ
Chem/Ox and ERD
Treatment of
Groundwater
Destroys CVOCs page 1
Vegetable Oil
Emulsion Promotes
Contaminant
Degradation in
Bedrock
Groundwater
page3
Benzene and Xylene
Degradation
Accomplished
through Ozone
Sparge Technology page 4
EPA Issues New
Policy and Strategy
to Reduce
Environmental
Footprints of
Cleanup
page6
Online Resources
CLU-IN's online area for
vendor support offers tools
to help technology developers
and vendors advance innova-
tive methods for using
technologies such as in-situ
chemical oxidation. The tools
span product development
stages ranging from bench-
scale testing through full
commercialization, and
address business planning,
marketing, financing, and
related technical issues
(www.cluin.org/vendor/).
Recycled/Recy cl abl e
Printed with Soy/Canola Ink on paper that
contains at least 50% recycled fiber
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Table 1. Interim source
removal actions at the
Pinellas Park site over
the past five years have
involved sequential
injections ofFenton 's
reagent, KMnO4 and
emulsified oil substrate.
[continued from page 1]
to destroy large masses of
CVOCs in a short period
of time. Implementation
involved separate injections
of 50% hydrogen peroxide solution and
soluble ferrous iron salts. In the course of
three events, approximately 18,000
gallons of solution were injected at a rate
of 0.75-1.5 gpm in permanent treatment
wells and direct push locations. The
highest dissolved TCE concentrations
were reduced 90% or more within three
months. Levels then began to rebound as
CVOCs desorbed from the soil, signaling
the point to implement follow-on remedial
technologies.
Since KMnO4 is a longer-lived chemical
oxidant than Fenton's reagent, it was
administered after the majority of DNAPL
and high dissolved concentrations of
CVOCs were depleted and the slow
desorption of parent CVOCs had begun.
Emulsified soybean oil, serving as an
electron donor, and proprietary bacteria
were injected to enhance and augment
reductive dechlorination after chem/ox was
complete. Additional solutions were
injected to raise groundwater pH or increase
nutrient concentrations in an effort to
further enhance reductive dechlorination.
As of September 2009,16 events involving
reagent injection or groundwater
conditioning had been completed (Table 1).
A network of 216 permanent treatment
wells screened over three depth intervals
and 96 direct push locations have been
employed. Potable water or very weak
reagent solutions were typically injected
last into each well to minimize inorganic
| Reagent Injection or Groundwater Conditioning Event
I Fenton's reagent injection: source areas 1, 2, 3, and 4
1 First pH adjustment
1 Emulsified oil substrate (electron donor) injection
1 Second pH adjustment
1 Bacterial inoculation
1 Groundwater pH adjustment
1 Groundwater pH adjustment
I Groundwater pH adjustment
1 Emulsified oil substrate injection: source area 1
1 Groundwater pH adjustment: SA1, source area 1
1 Fenton's reagent injection: SA, source areas 2, 3, and 4
Fenton's reagent injection: SA, source areas 2, 3, and 4
KMnO 4 injection: SA, source areas 2, 3, 4, and 5 and ICU2 source areas 1 and 2
Emulsified oil substrate injection: source area 1
Groundwater pH adjustment: source areas 1, 2, and 4
KMnCUinjection: SA, source areas 2, 3, 4, and 5
Date
September 2004
October 2004
December 2004
January 2005
January 2005
May 2005
August 2005
August 2006
August 2006
April 2007
April-August 2007
February 2008
April 2008
May 2008
May 2008
June 2008
' SA (surficial aquifer) 2 ICU (intermediate confining unit)
and biological screen plugging. This
technique allowed many treatment wells to
be used ten times or more, although several
wells were damaged beyond reuse
(particularly during Fenton's treatment).
The Fenton's reagent produced a
significant volume of reaction gases,
particularly in lower portions of the surficial
aquifer where groundwater flow rates are
low and reagent doses were highest. The
low soil permeability limited the spread of
reaction gases and allowed pressure to
build, forcing groundwater and reagent
solutions upward along treatment well
casings or injection tooling. Depending on
the competence of building floors or
pavement, liquids remained below grade or
flowed onto the surface. Daylighted liquid
was neutralized with a reducing solution.
Chem/ox also depressed pH of the
groundwater to a sub-optimal level for
reductive dechlorination. Groundwater pH
was further reduced, in some cases to below
5.0, during reductive dechlorination due to
the low buffering capacity of the surficial
aquifer. As a result, approximately 3,000
pounds of potassium hydroxide and
potassium bicarbonate (in solution) have
been injected to raise the pH.
Naturally high aquifer temperatures
averaging 75°F provided excellent
conditions for ERD following chem/ox.
Edible oil substrate (EOS) was injected in
the form of soybean oil. One month after the
initial EOS delivery, an anaerobic bacterial
blend containing Dehalococcoides
ethenogenes (DHE) was inoculated.
Augmentation of the existing population
of DHE, the only bacteria found to
completely dechlorinate PCE to ethane,
provided a low-cost method for significantly
accelerating biodegradation. Over three
events, approximately 65,000 pounds of EOS
were injected.
During a June 2009 sampling event, 134
monitoring wells were sampled for 11
VOCs. Results indicated that the highest
pre-treatment TCE concentration (470,000
|Ig/L) had decreased 99.9%, to 240 |lg/L.
PCE and cDCE in the same well had
decreased 99.3% and 23%, respectively,
while vinyl chloride concentrations
increased 1,800%. Vinyl chloride
concentrations in a monitoring well 120 feet
downgradient were found to decrease from
a post-treatment high of 1,200 to 310 |lg/L,
documenting shrinkage of the plume.
Although concentrations of daughter
compounds (which are more soluble than
their parents) had risen for three to six
months in some monitoring wells during
the course of treatment, June analytical
results indicated that total moles of PCE,
TCE, cDCE, and vinyl chloride in most wells
continues to decrease.
Review of the project to date shows that
chem/ox was able to destroy DNAPL and
reduce dissolved PCE and TCE
[continued on page 3]
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[continued from page 2]
concentrations to a greater degree than
reductive dechlorination in the short term;
however, desorption of soil-adsorbed
CVOCs typically caused a rebound in
contaminant concentrations after
oxidants were consumed or dissipated. In
contrast, ERD has continued to destroy
contaminants one to two years after each
EOS injection. Additional remedial
technologies will be evaluated for achieving
the final cleanup goals, due to the extended
cleanup duration caused by production and
subsequent degradation of less chlorinated
daughter products during ERD.
Contributed by Simone Core, FL
Department of Environmental Protection
(Simone.Core@dep.state.fl.us or
813-632-7600), Farsad Fotouhi, Pall
Corporation (Farsad_Fotouhi@pall. com
or 734-913-6130), and Jerry B. Lisiecki,
Ph.D., Fishbeck, Thompson, Carr &
Huber, Inc. (jblisiecki@ftch.com or
616-464-3751)
Vegetable Oil Emulsion Promotes Contaminant Degradation in Bedrock Groundwater
ERD of CVOCs was implemented in 2007
within a fractured bedrock aquifer at Solid
Waste Management Unit 87 (S WMU 87)
of the former Naval Surface Warfare
Center (NSWC) in White Oak, MD. Work
focused on bioremediation of
contaminant hot spots through injection
of an emulsified oil substrate (EOS)
containing commercial-grade vegetable oil
directly into the bedrock aquifer, which
required pneumatic fracturing to enhance
distribution of the emulsion. The project
was initiated on a field-scale test basis,
and one year of quarterly monitoring
showed successful results.
SWMU 87 is one of 120 remedial areas of
concern that were identified after closure
of NSWC White Oak in the early 1990s.
The area encompasses three acres
located 50 feet from a large creek within a
steep valley. Site geology consists of
coastal plain deposits over fractured
metamorphic and igneous bedrock.
Groundwater depth ranges from 15 feet
bgs in low-lying areas along the creek to
more than 25 feet bgs at higher elevations.
The upper five feet of the fractured
bedrock has been weathered to saprolite
through which groundwater flows at a
rate of 0.4 ft/day. Contaminants existed
primarily in the saprolite surficial aquifer
but some were detected in the bedrock
aquifer. The primary contaminant of
concern was PCE, which was detected in
concentrations ranging from 9 to 120 (Ig/L.
exceeding the 5 |J.g/L maximum
contaminant level (MCL). TCE and cDCE
also were detected at concentrations
exceeding the site's risk-based media
cleanup goals, which were set at the 5 (Ig/L
MCL for TCE and 70 |ig/L MCL for cDCE.
Several rounds of vegetable-oil emulsion
injections were previously performed
successfully for bioremediation at NSWC;
however, pneumatic fracturing was added
to the injection process at SWMU 87 due to
limited permeability of the saprolite. Based
on information from the site investigations,
remedial work targeted a 14,000-ft2 area at
the depth of 15-35 feet bgs to treat
groundwater in the bedrock aquifer. Prior to
treatment, the aquifer was mildly aerobic,
with an average dissolved oxygen
concentration of 5 mg/L and an average
oxidation/reduction potential of +240 mV.
Pneumatic fracturing was performed to
increase bulk permeability of the formation
and dilate the existing fracture network
within the weathered bedrock matrix, thereby
increasing interconnecting fractures that
would provide more contact between the
injected carbon substrate and contaminants.
High-pressure nitrogen was used to create
fractures emanating at six 3-foot intervals in
each of 45 30- to 45-foot boreholes that would
be used for substrate injection.
Pneumatic fracturing followed by EOS
injection was conducted from May 7 until
June 3, 2007, using a fracturing/injection
process that required less than three hours
for each injection well. Pressures required
to "break the formation" and initiate
fracturing ranged from 60 to 700 psi, which
indicated a very heterogeneous aquifer. The
typical initial fracturing pressure was
approximately 300 psi. Once the formation
yielded to initial pressure, typically a few
seconds later, the maintenance pressure
required to continue fracturing decreased
to 140 psi. At this pressure, nitrogen
flowed into the formation at approximately
2,000 cfm for the duration of the pneumatic
fracturing process. Sixteen intervals could
not be fractured with pressures reaching
700 psi (the upper limit of safe operation
of the pneumatic fracturing unit). This
indicated competent bedrock rather than
the targeted unit of saprolite. In addition
to monitoring the nitrogen flow rates and
pressure in fracturing wells, pressures in
adjacent wells were recorded and
associated ground heave was measured.
Minimal ground heave occurred, with a
maximum of 0.5 inches that occurred during
initial fracturing and an average of 0.1-0.2
inches throughout the fracturing process.
Immediately following pneumatic
fracturing, the emulsified oil substrate was
pumped under low pressure (ranging from
35 to 250 psig) into each of the 45
boreholes. The average volume pumped
into each interval of a borehole was 53
gallons of a 60% vegetable oil emulsion
followed by 57 gallons of chase water.
Since some intervals had not fractured,
the balance of oil was pumped into
adjacent intervals or injection wells to
ensure the full target volume of 10,440
pounds was placed in the formation. Five
existing monitoring wells located within
30 feet of the injection points were used
to monitor substrate distribution and
[continued on page 4]
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[continued from page 3]
persistence and to assess treatment
effectiveness over time.
Substrate distribution was immediately
evident in adjacent injection wells through
visual observation of the vegetable oil
emulsion and measurements of elevated
total organic carbon (TOC) in groundwater
collected from monitoring wells. Field data
from the first round of quarterly monitoring
showed a significant TOC increase in all
monitoring wells (indicating sufficient
organic substrate was available for
biological activity) and a dissolved oxygen
increase from2.5 mg/L to a maximum of 6.3
mg/L. A sharp decline in dissolved oxygen
after six months of treatment, followed by a
non-detect level after nine months, indicated
that anaerobic biodegradation had
occurred. Further evidence of biological
activity included an increase in methane,
soluble iron, and soluble manganese
concentrations in all monitoring wells.
PCE concentrations in groundwater
decreased to below 5 mg/L in all treatment-
area wells within six months after the
injection (Figure 1). Over the following
year, notable rebound in contaminant
concentrations was observed in two
monitoring wells (87WP102 and 87WP202)
located 40 feet downgradient and 20 feet
crossgradient, respectively, of the
treatment zone. Monitoring at the
downgradient well closest to the creek
(87WP103) indicated a steady decline in
PCE concentrations and moderate
increases in PCE daughter products after
the injection, which suggested that PCE
migration was not occurring.
100
Oct 06 Apr 07
Oct 07 Apr 08
Date
Oct 08
Figure 1. A 97%
reduction in PCE
concentrations was
measured in treatment-
area monitoring wells
approximately nine
months after EOS
injection at the former
Naval Surface Warfare
Center SWMU 87.
Apr 09
Groundwater sampling data on PCE
degradation products such as DCE and vinyl
chloride indicated that PCE reduction by way
of sequential dechlorination had occurred.
Average DCE concentrations increased from
approximately 1 mg/L to 23 mg/L during the
first six months after the injection but
decreased to 8 mg/L approximately 12 months
later. cDCE remained relatively unchanged
from an average of approximately 1 mg/L for
the first three months after the injection but
increased to 23 mg/L over the next three
months. Concentrations of vinyl chloride
reached 5 mg/L approximately one year after
the injection, with a high of 17 mg/L in one
well. Over the following 10 months, the average
vinyl chloride concentration decreased to
0.6 mg/L, as concentrations of daughter-
product ethene increased dramatically (315%);
treatment well monitoring showed that
dissolved-phase ethene concentrations
peaked at 6.5 mg/L. Total CVOC
concentrations averaged approximately 12
mg/L in August 2008, a 55% reduction from
the pretreatment average of 3 0 mg/L.
Results from the last round of groundwater
monitoring in August 2008 indicate that the
average total CVOC concentration had
continued to decrease due to natural
attenuation, to approximately 55% of the
concentration prior to the single EOS
injection in 2007. Follow-up sampling to
evaluate continued natural attenuation is
scheduled for November 2009. Project
costs to date total approximately $712,000,
including costs for installing the 45
injection wells and two monitoring wells
and performing pneumatic fracturing/
injection at each injection well.
Contributed by Dave Steckler, U.S. Navy
(david.steckler@navy.mil or
202-685-8056), Steven G. Kawchak
(Shaw Environmental and
Infrastructure Inc.
(sgkawchak@shawgrp.com or
609-588-6349), and Michael Liskowitz,
ARS Technologies
Benzene and Xylene Degradation Accomplished through Ozone Sparge Technology
A RCRA corrective action involving ozone
sparging was undertaken in 2008 at a
gasoline- and diesel-contaminated site in
eastern Louisiana to remediate soil in a low-
permeability formation. Sparging with
ozone as an oxidant was selected over
other in-situ chem/ox techniques because
it was projected to meet cleanup goals
within three to six months. Final performance
results and follow-up monitoring indicated
that cleanup goals were reached within three
months, allowing complete shutdown of the
system five months later.
The site is located in the City of Vidalia
along the Mississippi River. In general, the
site's upper 16 feet of soil consists of moist
silty clay. In most of the 23 borings
advanced at the site, saturated soil
conditions were encountered at depths
ranging from 4 to 16 feet bgs. Adsorbed
benzene and xylenes were identified as the
constituents of concern, with
[continued on page 5]
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[continued from page 4]
concentrations of 160 and 1,050 mg/kg,
respectively. The site-specific Louisiana
Risk Evaluation Corrective Action Program
(RECAP) cleanup standards for benzene
andxylenes in soil are 9.7 and 490 mg/kg,
respectively. Residual constituents in
groundwater were below the site-
specific RECAP standards and therefore
did not require further remediation. The
target treatment area encompassed
approximately 750 ft2, with no apparent free
product in groundwater. Based on
quantities of dissolved and adsorbed
contaminants in the saturated zone and
smear zone, the contaminant mass was
estimated at approximately 100 pounds.
In contrast to applications typical of other
in-situ chem/ox techniques, use of ozone gas
as a subsurface injectant allows for
continuous delivery of an oxidation agent.
The sparge process involves injection of
ozone gas into the groundwater through a
microporous oxidation point placed below
the water table. Injected ozone migrates
outward and upward through the
groundwater, initiating contaminant
oxidation as it moves through the
saturated region. Typical reaction
byproducts include carbon dioxide, water,
and inorganic chloride.
Ozone delivery to the subsurface
typically involves use of an air
compressor that pulls in ambient air and
passes it through an oxygen concentrator.
The concentrator removes ambient
nitrogen and delivers 90% pure oxygen to
the ozone generator after drying the air
stream. The ozone generator uses a high-
voltage electrical current to convert the
pure oxygen to ozone at 6%
concentration, by weight, of ozone. An
additional air compressor is used to blend
ambient air with the ozone, allowing the
ozone to be injected into the subsurface
at typical flow rates of 1 -4 cfm and up to
10 cfm at pressures reaching 50 psi.
This mixture of air and ozone is injected
directly into the groundwater through a
series of oxidation points equipped with a
microporous diffuser. A field programmable
PLC-based controller with an interface panel
viewer is used to control the manifold,
allowing field personnel to enable and
disable oxidation points, switch between
ozone and oxygen injection, set lag time
between sparge cycles, and set sparge
duration, as necessary.
Calculation of the ozone mass required at the
site considered inorganic compounds in
groundwater that could act as oxygen
receptors and potentially increase the demand
for ozone during treatment. In the absence of
these data, the anticipated ozone mass to be
delivered was increased by 25%.
Sparging began in mid December 2008. Ozone
was generated by a portable unit capable of
producing up to 2.72 pounds of ozone per
day (Figure 2). The ozone was delivered to
the subsurface through 20 sequential
injection points by use of a pump with a
maximum delivery rate of 3.8 cfm at 50 psi.
Nine 1-inch diameter oxidation points set
approximately 16 feet bgs and positioned in
a triangular grid were used to achieve a 10-
foot radius of influence. The system was
programmed to sparge ozone alternating
between each oxidation point for 20 to 30
minutes cycles and then shut down for a
30-minute cool-down period before
restarting the next cycle. All equipment was
made of ozone-compatible material such as
stainless steel, Teflon, Kynar, Viton, and
schedule 80 PVC, instead of high-density
polyethylene and natural rubbers that
could easily degrade.
Soil samples taken after three months of
ozone sparging indicated a benzene
concentration of 0.57 mg/kg and total
xylene concentrations of 44.9 mg/kg, a
respective 99.6% and 95.7% reduction
from pre-treatment concentrations. The
ozone sparge system was shut down in
March 2009 when an additional soil
sampling event indicated that benzene
and total xylene concentrations were
below the site-specific RECAP
standards. Demobilization and the
plugging and abandonment of monitoring
wells were conducted in August 2009,
after confirmation soil sampling indicated
successful remediation of benzene and
xylenes. A "No Further Action" letter is
anticipated, pending final approval of the
data by the LDEQ.
Costs for installing the ozone sparge
system and three months of operation
totaled approximately $134,570, including
$ 118,220 for equipment, installation, and
startup expenses. The remaining project
costs were allocated to three months of
operation and maintenance, which
averaged $5,450 each month and included
$200 per month for utilities.
Contributed by Durwood Franklin,
LDEQ (durwood.franklin@la.gov or
318-362-5439) and
Charles R. Plummer,
IMT, LLC
(rickplummer@imtco.net
or 318-325-1830)
Figure 2. Ozone
sparge equipment used
at the City of Vidalia
site consisted of a 20-
point, 52-g/hr (2.72
Ib/day) ozone sparging
system housed in a
mobile trailer.
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Solid Waste and
Emergency Response
(5203P)
EPA 542-N-09-006
December 2009
Issue No. 45
United States
Environmental Protection Agency
National Service Center for Environmental Publications
P.O. Box 42419
Cincinnati, OH 45242
Official Business
Penalty for Private Use $300
Presorted Standard
Postage and Fees Paid
EPA "
Permit No. G-35
EPA Issues New Policy and Strategy to Reduce
Environmental Footprints of Cleanup
The U.S. EPA recently released its Principles for Greener Cleanups to improve the
decisionmaking process for cleanup activities in a way that reduces adverse impacts
of cleanups on communities (www.epa.gov/oswer/greencleanups). In light of the
principles, EPA concurrently released a Superfund Strategy for Green Remediation to
outline the Agency's actions and initiatives for reducing the footprints specifically at
Superfund sites (www.epa.gov/superfund/greenremediation). The principles and
strategy aim to reduce the environmental footprint by:
> Minimizing energy consumption and maximizing use of renewable energy
> Minimizing air pollutants and greenhouse gas emissions
> Minimizing water use and impacts to water resources
> Reducing, reusing, and recycling material and waste
> Protecting land and ecosystems
To help project managers and other stakeholders routinely apply the principles and
strategy, the Agency is developing a series of fact sheets recommending best
management practices for commonly used technologies such as soil vapor extraction,
bioremediation, and ex situ treatment of groundwater. For more information about the
practices, contact Carlos Pachon in EPA's Office of Superfund Remediation and
Technology Innovation (pachon.carlos@epa.gov). The full range of environmental,
energy, and economic aspects of green and sustainable remediation also will be
addressed at the International Conference on Green Remediation to be held in Amherst,
MA, in June 2010 (www.umass.edu/tei/conferences/).
Contact Us
Technology News and Trends
is on the NET! View, download,
subscribe, and unsubscribe at:
www.epa.gov/tio
www.clu-in.org/newsletters
Contributions may be submitted to:
John Quander
Office of Superfund Remediation
and Technology Innovation
U.S. Environmental Protection Agency
Phone:703-603-7198
quander.john@epa.gov
DNAPL Guidance
The Interstate Technology & Regulatory
Council (ITRC) offers a three-part series
of guidance documents on in-situ
bioremediation of chlorinated ethene
DNAPL source zones. The series
provides an overview of the issues, case
studies, and a review of technical and
regulatory considerations. To download
the guidance, visitwww.itrcweb.org/
guidancedocument.asp?TID=47.
EPA is publishing this newsletter as a means of disseminating useful information regarding innovative and alternative treatment techniques and
technologies. The Agency does not endorse specific technology vendors.
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