SEPA
United States
Environmental Protection
Agency
Office of Solid Waste and
Emergency Response (5203P)
EPA 542-F-12-029
October 2012
Green Remediation Best Management Practices:
Implementing In Situ Thermal Technologies
Office of Superfund Remediation and Technology Innovation
Quick Reference Fact Sheet
The U.S. Environmental Protection Agency (EPA) Principles for
Greener Cleanups outline the Agency's policy for evaluating
and minimizing the environmental "footprint" of activities
undertaken when cleaning up a contaminated site.1 Use of
the best management practices (BMPs) recommended in
EPA's series of green remediation fact sheets can help project
managers and other stakeholders apply the principles on a
routine basis while maintaining the cleanup objectives,
ensuring protectiveness of a remedy, and improving its
environmental outcome.
Over recent years, the use of in situ thermal (1ST) systems
to remediate contaminated sites has notably increased.
Since fiscal year 2005, for example, remedies involving
1ST technology have been selected for 18 Superfund sites.
1ST technologies also have been used more frequently for
RCRA corrective actions, brownfield sites, or military
installations needing accelerated cleanup. When properly
applied in well-defined contaminant source zones, 1ST
technologies may effectively remediate a site within
months rather than years.
1ST implementation typically involves independent or
combined use of three primary technologies to apply heat
in targeted subsurface zones: electrical resistance heating
(ERH), thermal conductive heating (TCH), and/or steam
enhanced extraction (SEE). 1ST implementation also relies
on soil vapor extraction (SVE) to collect and carry the
chemical vapors to the surface for treatment. Other
remediation system components that may be used in
conjunction with 1ST technologies include pumping
networks to control groundwater flow in the treatment
zone and dual-phase extraction wells to extract source
water, non-aqueous phase liquid (NAPL), and vapor. By
aggressively treating the source area, 1ST implementation
can significantly reduce the amount of contamination
needing to be addressed by groundwater cleanup efforts.
1ST technologies can be used to:
• Treat contaminant source areas in diverse geologic
strata, including clay, silt, sand, and fractured bedrock
• Remove volatile organic compounds (VOCs) and
semivolatile organic compounds sorbed to the soil in
both the saturated and unsaturated (vadose) zones of
the subsurface
• Capture and treat contaminants existing in the non-
aqueous phase, or
• Strip dissolved contaminants from groundwater.
The environmental footprint of implementing these
technologies can be reduced by adhering to EPA's
Principles for Greener Cleanups. The core elements
of a greener cleanup involve:
• Reducing total energy use and increasing the
percentage of renewable energy
• Reducing air pollutants and greenhouse gas (GHG)
emissions
• Reducing water use
and negative impacts
on water resources
• Improving materials
management and
waste reduction
efforts, and
Protecting ecosystem
Materials
& Waste
Energy
Land&
Ecosystems
Air&
Atmosphere
Water
EPA's suite of green remediation BMPs describes
specific techniques or tools to achieve a greener cleanup.
Associated documents in EPA's "BMP fact sheet" series
provide detail about BMPs applying to various
remediation technologies, cleanup phases, or common
issues.2 The BMPs are intended for general use or
adaptation wherever feasible; for example, BMP
modifications may be necessary to account for the
relatively short duration of most 1ST applications.
Opportunities to reduce the environmental footprint of 1ST
applications correlate to the common cleanup phases:
> Design, including ERH, TCH, and SEE components as
well as vapor extraction systems
> Construction
> Operation and maintenance, and
> Monitoring.
Design
Green remediation strategies for designing an 1ST system
depend on a thorough understanding of the site
hydrogeology and contaminant location(s) to assure that:
• The target zone, including the majority of source-area
NAPL, receives treatment
• System modifications such as reduced heating rates or
duration can be made for selected areas during project
design or as treatment progresses, and
• Areas outside the target zone are not heated.
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This assurance helps allocate resources effectively and
avoid unnecessary expenditure of water, energy, and
other natural resources. It also helps minimize emission of
air contaminants, generation of additional waste, and
disturbance to land and existing ecosystems throughout
the life of the project. Green remediation BMPs
particularly applying to 1ST system design include:
• Test and refine the conceptual site model previously
developed during site investigation, and prepare for
additional refinements during system construction and
operation
• Conduct comprehensive soil sampling to assure that
data used for determining baseline electrical resistivity
represent the entire treatment area; for example, wetter
soil areas may need lower power inputs than dryer
areas in order to propagate an electricity current and
meet target temperatures
• Maximize use of waterless direct-push drilling tools for
screening purposes, such as a membrane interface
probe for VOCs or a laser-induced fluorescence probe
for petroleum hydrocarbons, rather than more invasive
and energy-intensive rotary drilling techniques needed
for confirmatory sampling, and
• Use other high-resolution imagery techniques such as
seismic reflection to confirm stratigraphic continuities.3
Additional BMPs are described in Green Remediation Best
Management Practices: Site Investigation.2"
Effective 1ST system design also relies on analytical models
to optimize the spacing of heating wells in relation to
energy use and heating duration and the efficiency of
vapor recovery equipment. Modeling efforts may be aided
by applying EPA's A/lefhodo/ogy for Understanding and
Reducing a Project's Environmental Footprint, which
provides an approach to quantifying a project's energy,
air, water, materials, and waste components.4
EPA's footprint assessment "methodology" was used for
designing 1ST implementation and excavation with offsite
disposal to remediate the South Tacoma Channel Well
12A site in Washington. Although 1ST technology is energy
intensive, its estimated environmental footprint was found to
be lower at this site when compared to excavation. The lower
footprint was attributed to the site's available electricity, which
is supplied by offsite facilities where more than 98% of the
power is generated from hydroelectric and nuclear resources.
Based on the footprint assessment results, remedial designs
were modified to reflect smaller excavation areas (involving
an approximate 50% reduction in the excavation volume) and
a corresponding, larger 1ST target zone. BMPs used to reduce
the footprint of the remaining excavation/disposal efforts and
construction of the 1ST system included:
* Using cleaner engines, cleaner fuel, and diesel emission
control technology on all diesel equipment
* Segregating and locally recycling excavated concrete, and
• Selecting the nearest soil "borrow" sources and waste
disposal facilities, to minimize transport and associated air
emissions.
Green remediation BMPs for general design of 1ST
systems include:
• Minimize piping runs from the extraction well field to the
treatment system
• Explore combined thermal treatment technologies at
sites with varying geologic units, to maximize efficiencies
• Consider a phased approach that sequentially heats
subareas of large sites, to reduce equipment needs and
identify opportunities for conserving energy and other
resources over time
Integrate sources of
renewable energy at
various scales, such as
small re-useable or
portable photovoltaic
systems or wind turbines
to provide supplemental
power for equipment
such as pumps or
blowers, and/or utility-
scale systems that may
be used for ongoing or
future site activities or
for sale as distributed
power,2b and
Establish a project base-
line on information such as electricity and water
consumption, volumes of material purchases, and
offsite disposal volumes, which can be used to identify,
implement, and measure continuous improvements to
an operating system and identify opportunities for
modifications resulting in major efficiency gains.
Sources of renewable
energy may include:
* Solar energy captured by
photovoltaic, solar ther-
mal, or concentrated so-
lar power technology
* Wind energy gathered by
mechanical windmills or
electricity-generating
turbines
* Biomass such as forestry
or agricultural waste
• Methane recovered from
landfill gas, and
• Hydropower from flowing
surface water or ocean
Most green remediation BMPs for 1ST implementation apply
to ERH, TCH, and SEE technologies, although different
processes and equipment involved in each can provide
unique opportunities to reduce their environmental footprint.
Electrical Resistance Heating
ERH technology involves subsurface placement of
electrodes that can accept three- or six-phase electrical
current. Resistance to the current's passage among the
electrodes causes heating of soil across the entire
treatment area or at selected subsurface intervals. To
facilitate soil contact with the electrode, graphite or steel
shot is placed around each electrode. Target
temperatures are generally 100 °C or the boiling point of
water, which may be higher at increased depths below the
water table. Loss of heat at ground surfaces is minimized
by installing a cap.
The contaminants are steam stripped or vaporized and the
steam/vapor is collected by vacuum vapor recovery wells
for treatment at the ground surface. At some sites, the
recovery wells can be constructed as dual-phase (liquid
and vapor) recovery wells. As the water boils off near
electrodes in the vadose zone, additional water is added
to maintain soil electrical conductance, usually through
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use of a drip tube system. The subsurface heating process
is monitored by thermocouples and pressure transducers.
The ex situ vapor treatment system typically includes
piping, one or more blowers, a knockout tank to separate
vapor from entrained water, a condenser for pre-
treatment cooling, and treatment equipment such as
granulated charcoal or thermal oxidation units. If
groundwater and/or NAPL is extracted, additional
equipment such as a separator tank with a water-
treatment system is required.
Green remediation BMPs for ERH system design include:
• Consider co-locating electrodes and recovery wells in
the same borehole, particularly in the saturated zone, to
minimize land disturbance
• Assure all electrodes are free of rust or debris before
placement, to maximize heat transfer
• Use condensate or treated water as makeup water for
the condenser cooling tower or recycle them into the
drip system, and
• Use off-gases from a thermal oxidation unit to help heat
recycled water for the drip system.
In 2007, an ERH system was installed at the Total
Petrochemicals & Refining USA Inc. former hulk fuel
terminal in Greensboro, North Carolina. This 1ST application:
* Used high resolution techniques and analytical modeling to
divide the site into four 1.2-acre zones and develop a
phased heating approach that optimized use of electricity
and natural gas
* Used a real-time control system that allowed discrete
targeting of specific subsurface depth intervals for heating
on a minute-by-minute basis to increase heating efficiency
• Reused treated water to maintain moisture at electrodes
* Used an air-water heat exchanger that allowed the thermal
oxidizer off-gas to serve as a source of heat for pre-heating
water prior to its reuse at the electrodes
* Included frequent process review and optimization to focus
the use of power and other resources on hotspots, and
* Repurposed the recovered/recondensed waste product
(gasoline) through sale to local fuel recyclers.
By the end of active heating in the fourth (final) zone in 2012,
approximately 880,000 pounds of contaminant mass
(approximately 75% of the original mass estimate) had been
recovered. A total of 10.4 MW/hr of electricity was used to
operate the ERH system, at a cost of $1.8 million. The overall
unit cost for this 1ST remedy was $90-95 per cubic yard.
2007 Groundwater Remediation Award
National Ground Water Association
Thermal Conductive Heating
Thermal conductive heating (also known as in situ thermal
desorption) supplies heat to the soil through steel wells
that contain heaters reaching to various depths. In areas
of shallow groundwater, TCH implementation may involve
horizontal in addition to vertical wells for vapor extraction
in order to minimize upwelling caused by vacuum
extraction. BMPs for TCH design include:
• Assure suitable sizing of in-well heating units, to
optimize energy use
• Include feedback loops in the process control system, to
allow precise application of heat and the desired
temperature and duration
• Explore the use of natural gas-fired systems that enable
in-well combustion of the contaminants and recovery of
associated heat, resulting in a lower energy demand
• Integrate a combined heat and power (CHP) system
powered by natural gas or cleaner diesel, to generate
electricity while capturing waste heat that can be used
to condition air inside buildings used for vapor
treatment or other onsite operations, and
• Choose designs that allow post-cleanup reuse of the
underground piping network for infrastructure
components such as geothermal systems.
Steam Enhanced Extraction
SEE technology involves introduction of steam to the
subsurface by injecting it from ground surface into wells.
The resulting condensate and excess steam are extracted
for above-ground treatment through conventional water
and vapor treatment systems. Green remediation BMPs
unique to SEE technology include:
• Choose a water-tube boiler rather than a fire-tube
boiler wherever feasible; the smaller tubes in water-tube
boilers increase boiler efficiency by allowing more heat
transfer from exhaust gases
• Consider adding pipe insulation to prevent heat loss
and increasing insulation wherever feasible for other
components most susceptible to heat loss
• Install heat recovery equipment such as feedwater
economizers and/or combustion air preheaters, to
recover and use heat otherwise lost in exhaust gas
• Minimize excess air in the steam generation process, to
reduce the amount of heat lost through the stack, and
• Install solar thermal equipment to preheat boiler feed-
water and makeup water, to reduce the energy needed
for raising water temperatures to the target levels.
More information about opportunities to improve steam
system performance and tools to assess steam systems is
available from the U.S. Department of Energy.5
SEE System Optimization: Rules of Thumb
Small changes in boiler efficiency can result in significant fuel
conservation and related cost savings. For example:
• A typical natural-gas fired 120,000 pounds/hour industrial
boiler producing 700 °F steam at a pressure of 400 psig
could cost $13 million to operate over one year;7 a boiler
efficiency improvement as small as 1% could reduce the
operating cost by $130,000.
* Boiler efficiency can be increased by 1% for each 15%
reduction in excess air or 4 °F reduction in stack gas
temperature.
" Minimizing the non-condensable matter in blowdown from
condensing equipment for boiler systems is critical; every
1% of non-condensables in steam can cause a 10%
reduction in the heat transfer coefficient.7
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Cleanup of Operable Unit 2 at the Grove/cmd Wells
Superfund Site in Grove/and, Massachusetts, in 2010-
201 1 involved ERH technology with enhanced in situ steam
production to address a trichloroethene (TCE) source area.
Implementation included:
• Subsurface injection of water-conditioning salts to increase
electrical conductivity of the soil
• Installation of a sound-absorbing curtain to reduce
transmission of high frequency sounds emitted by the vapor
extraction system blowers
• Use of a steam generator to operate 14 steam "spears"
that increased moisture content and electrical conductivity
in targeted portions of the shallow vadose zone, and
* Installation of two 2-inch-thick polystyrene insulating
boards directly above the concrete vapor cover, to reduce
heat loss by approximately 98% during unexpected winter
operations.
Electricity costs for the six-month ERH application, steam
enhancement, and extraction systems totaled approximately
$604,000. Upon system shutdown, performance data
indicated removal of over 1,300 pounds ofVOCs and a 97%
reduction in source area TCE concentrations.
Soil Vapor Extraction
The environmental footprint of systems used for ex situ
treatment of vapors extracted from 1ST systems is affected
significantly by generation of material waste and
wastewater as well as consumption of energy. Roughly
70% of SVE systems at Superfund sites have used granular
activated carbon (GAC) treatment and approximately 25%
used thermal or catalytic oxidation. Wastes potentially
needing offsite treatment and disposal include spent non-
regenerable carbon canisters or liquid condensate from
air/water separators. Green remediation BMPs for
designing vapor extraction systems include:
• Use the minimum air flow rate that can meet the
cleanup objectives and schedule while minimizing
energy consumption
• Assure suitable sizing of vacuum pumps and blowers
that are used to extract air from the subsurface, which
will optimize energy use
• Consider using combined cryogenic compression and
condensation technology instead of thermal oxidation to
treat vapor streams with high contaminant
concentrations; a cryogenic system allows recovery of
contaminant vapor as a liquid for potential recycling or
resale
• Treat condensate in onsite systems where contaminant
types and concentrations permit, rather than
discharging it to (and increasing the burden on) the
publically owned treatment works (POTW)
• Plan to recycle condenser water as supplemental
cooling water where concentrations permit, to minimize
use of fresh water
• Minimize sizing of above-ground structures that house
extraction or treatment equipment and use green
building elements such as passive lighting, rainwater
collection systems, and federally designated green
products,8 and
• Consider including horizontal wells in the well network,
to improve overall efficiency of air extraction.
Additional BMPs regarding vapor extraction system design
are available in Green Remediation Best Management
Practices: Soil Vapor Extraction & Air Sparing.2c
Since late 2009, a
cryogenic compression
and condensation process
has been used to recover
hydrocarbons from SVE
operations at the State
Road 114 Superfund site
in Levelland, Texas. Over
the first seven months of
operation, the process
brought in project revenue
of approximately $45,000,
approximately 70% of the
SVE system's electricity
costs.
Construction
Well installation can significantly contribute to the
environmental footprint of 1ST system construction. Green
remediation BMPs that can help reduce the environmental
footprint of construction activities relating to wells and
other 1ST system components include:
• Use direct-push technology (DPT) for well installation
wherever feasible, to eliminate drill cuttings and
associated waste disposal, avoid consumption or
disposal of drilling fluids, and reduce drilling duration
by as much as 50-60% when compared to conventional
rigs; for example, DPT can be used to install standard
2-inch diameter vacuum extraction wells, air injection
wells, groundwater depression wells, and monitoring
points
• Segregate drill cuttings by appropriately stockpiling next
to a borehole and awaiting analytical results; under
many cleanup programs, clean soil may be distributed
near boreholes or backfilled into a boring
• Choose ground surface capping materials containing
recycled contents9
• Install a thermal insulation vapor cover to maximize 1ST
operations in cold climates, and
• Winterize all above-ground piping before onset of
freezing temperatures, to avoid downtime and
inefficiencies associated with freezing temperatures.
Evaluating the options may include consideration of
potential environmental tradeoffs. In the case of using
DPT, for example, its deployment ease can reduce fuel-
intensive field activities; however, attempted DPT use at
depths approaching the technology's typical limit (100
feet) could result in wasted fuel or well installation failure.
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Another example is the use of small-diameter injection
wells that can lead to large pressure drops and increased
energy consumption of the system.
Emission of GHG and particulate matter from trucks and
other mobile sources during 1ST construction can be
reduced through BMPs such as:
• Retrofit equipment for cleaner engine exhaust
• Use ultra low-sulfur diesel in heavy machinery, and
• Institute a reduced idling plan.
Additional BMPs regarding fuel conservation and reduced
air emissions from stationary as well as mobile sources
are provided in Green Remediation Best Management
Practices: Clean Fuel & Emission Technologies for
Cleanup211
Other BMPs that can be used during 1ST system
construction involve minimizing disturbance to the land,
ecosystems, and nearby residents or workers.
• Include sound-proofing material in aboveground
housing for vapor extraction equipment that often
generates high levels of noise; acoustic barriers with
recycled or recyclable components may be constructed
onsite or obtained commercially
• Choose centrifugal blowers rather than positive
displacement blowers (which tend to generate more
noise) if the applied efficiencies are comparable
• Install air-line mufflers to decrease equipment noise
• Install directional shields on significant lighting sources
such as safety beacons for the power distribution
system, to minimize visual disturbance of nearby human
or animal populations
• Limit tree removal to only those truly obstructing
construction or operation of the treatment systems, and
• Transplant any shrubs from proposed extraction points
to other onsite locations.
Project footprints on water resources may be reduced
during construction by BMPs such as:
• Install mechanisms to reclaim treated groundwater for
onsite use such as dust control, vegetation irrigation, or
process input for other treatment systems
• Devise methods to re-inject uncontaminated
groundwater that was pumped solely for the purpose of
depressing the water table (and consequently preventing
upwelling) rather than discharging it to the POTW
• Create grassed swales or grass-lined channels outside
the treatment area, to minimize incoming stormwater
runoff and route it to landscaped areas for gradual
infiltration or evapotranspiration, and
• Choose porous asphalt that allows water percolation,
rather than impermeable concrete, to cover ground
surfaces of adjacent work or storage areas.
Additional BMPs regarding treatment, conservation and
management of water during site cleanup are available in
Green Remediation Besf Management Practices: Pump
and Treat Technologies.2"
Operation and Maintenance
Potential inefficiencies contributing to the environmental
footprint of 1ST applications often relate to release of
contaminant vapors through vertical short-circuiting,
incomplete treatment of off-gases, or migration of vapors
beyond the treatment zone. Unintended vapor emissions
or system inefficiencies can be reduced by BMPs such as:
• Consider adding a low-permeability soil cap at an area
with negative pressure to prevent intrusion of clean air
that can short circuit the extraction system
• Assure that the zone of influence of vapor extraction
wells completely covers the treatment area
• Properly maintain surface seals around all wells and
monitoring points
• Avoid or minimize dewatering when lowering of the
water table is unneeded to treat the smear zone or
otherwise unnecessary, by reducing the applied vacuum
or installing additional extraction vents
• Maintain flow rates sufficient to prevent vapors from
migrating beyond the treatment area without
overloading the treatment system
• Regenerate adsorbtive media such as GAC filters, and
• Modify the vapor treatment system as needed, to
accommodate changing influent vapor concentrations
as treatment progresses.
Periodic remedial system evaluation can help identify
BMPs to improve performance and efficiency of 1ST system
operations (including vapor or dual-phase extraction
processes) as cleanup progresses, such as:
• Re-evaluate efficacy of the air/vapor treatment on a
periodic basis, to identify any opportunity for reduced
material use or waste generation
• Periodically re-sample groundwater of a dual-phase
extraction system to assure adequate characterization
and treatment of light non-aqueous phase liquid
(LNAPL); for example, mineral spirit LNAPL associated
with VOC contamination can generate a need for
increased backwashing
• Adjust flow rates as needed to obtain the minimum air
flow and maximum amount of contaminants per volume
of vapor removed
• Shut down equipment no longer needed; for example,
electrodes or recovery wells in some areas may be shut
down as soon as performance levels are met while
others continue to operate
• Modify any wells no longer contributing contaminants
within a given manifold system, despite proper well
functioning, or take them offline, and
• Develop an exit strategy, including performance values
that trigger termination of the active heating process;
for example, a pre-defined level of diminishing returns
could prompt heating system shutdown and conversion
to one or more remediation "polishing" technologies
with a smaller environmental footprint.
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Monitoring
Decreases in field visit frequency and associated fuel and
material consumption or waste generation during system
monitoring can be achieved through BMPs such as:
• Increase automation through use of equipment such as
electronic pressure transducers and thermo-couples with
an automatic data logger (rather than manual readings)
to record data at frequent intervals
• Use electrical resistance tomography to monitor soil
moisture levels that may vary over time, which affects
the project's soil resistivity estimates and associated
energy demands
• Use field test kits or analyze for only indicator
compounds whenever possible
• Monitor soil temperatures on a regular basis to assure
uniform heating in target areas and avoid unexpected
heating and energy waste in non-targeted areas, and
• Use a control system that can be remotely accessed to
avoid bringing staff to the site daily.
Implementing In Situ Thermal Technologies:
Recommended Checklist
Design
Establish a conceptual site model
Maximize use of high-resolution imagery techniques
Consider a phased heating approach
Integrate sources of renewable energy
Establish a baseline on resource consumption and
waste generation
Construction
Consider co-locating wells with heating equipment
Choose materials with recycled contents
Employ direct-push technology wherever feasible
Screen drill cuttings for potential onsite reuse
Integrate techniques to lower or buffer noise
Reclaim treated or clean pumped water for onsite
use or return to the aquifer
Employ cleaner fuels, clean emission technologies,
and fuel conservation techniques
Operation and maintenance
Maintain surface seals
Modify flow rates to meet changing site conditions
Continuously evaluate the potential for downsizing
or shutting down equipment as cleanup progresses
Monitoring
Maximize automated and remote monitoring
capabilities
Use field test kits whenever feasible
Include data collection from areas immediately
beyond the target area
Natural resource efficiencies during 1ST implementation can
he gained through acquisition of environmentally preferable
goods and services. EPA's Green Response and
Remedial Action Contracting and Administrative
Toolkit contains sample language for cleanup contracts and
potential reporting structures to help track associated
environmental improvements.10 Use of a performance-based
contract with clear criteria such as target heating
temperatures can also help assure a minimized
environmental footprint while controlling costs throughout the
life of an 1ST project.
References [Web accessed: October 2012]
1 U.S. EPA Principles for Greener C/eonups; August 27, 2009;
http://www.epa.gov/oswer/greenercleanups
2 U.S. EPA; Green Remediation Best Management Practices:
"Site Investigation; EPA542-F-09-004; December 2009
b Integrating Renewable Energy into Site Cleanup; EPA 542-F-l 1 -006;
April 201 1
c Soil Vapor Extraction & Air Sparging; EPA 542-F-l 0-007; March
2010
d Clean Fuel & Emission Technologies for Site Cleanup; EPA 542-F-
10-008; August 2010
e Pump and Treat Technologies; EPA 542-F-09-005; December 2009
3 U.S. EPA; Site Characterization Technologies for DNAPL
Investigations; EPA542-R-04-01 7; September 2004
4 U.S. EPA; CLU-IN Green Remediation Focus; Footprint Assessment:
http://www.cl uin.org/greenremediation/subtab_b3.cfm
5 U.S. DOE Advanced Manufacturing Office; Steam Systems;
http://wwwl .eere.energy.gov/manufacturing/tech_deployment/stea
m.html
6 U.S. DOE/EERE; DOE's Best Practices Steam End User Training;
September 8, 2010;
http://wwwl .eere.energy.gov/manufacturing/pdfs/efficiencydefinitio
n.pdf
7 U.S. DOE/EERE; Steam Generation, Distribution, Energy Use, and
Recovery;
http://wwwl .eere.energy.gov/manufacturing/tech_deployment/stea
mbasics.html#generation
8 U.S. General Services Administration; Green Products Compilation;
http://www.gsa.gov/portal/content/198257
9 U.S. Department of Transportation Federal Highway Administration;
User Guidelines for Waste and Byproduct Materials in Pavement
Construction;
http://www.fhwa.dot.gov/publications/research/infrastructure/structu
res/97148/
10 U.S. EPA; Greener Cleanups Contracting and Administrative Toolkit;
http://www.clu in.org/green re mediation/docs/Greener_Cleanups_C
ontracting_and_Administrative_Toolkit.pdf
EPA/OSWER appreciates the many contributions to this fact sheet, as
provided by EPA regions and laboratories or private industry.
The Agency is publishing this fact sheet as a means of disseminating
information regarding the BMPs of green remediation; mention of specific
products or vendors does not constitute EPA endorsement.
Visit Green Remediation Focus online:
http://www.cluin.org/greenremediation
For more information, contact:
Carlos Pachon, OSWER/OSRTI (pachon.carlos@epa.gov)
U.S. Environmental Protection Agency
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