EPA/540/8-91/009
May 1991
Synopses of Federal
Demonstrations of Innovative
Site Remediation Technologies
Prepared by the Member Agencies of the
Federal Remediation Technologies Roundtable:
U.S. Environmental Protection Agency
Department of Defense
U.S. Army
U.S. Army Corps of Engineers
U.S. Navy
U.S. Air Force
Department of Energy
Department of Interior
Bureau of Reclamation
Summer 1991
Printed on Recycled Paper
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NOTICE
The information in this document has been funded wholly by the United States Environmental Protection
Agency under Contracts 68-CO-0083 and 68-01-7481 to ICF Incorporated. It has been subject to
administrative review by all agencies participating in the Federal Remediation Technologies Roundtable,
and has been approved for publication. Mention of trade names or commercial products does not
constitute endorsement or recommendation for use.
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Table of Contents
BIOREMEDIATION
Above-Ground Biological Treatment of Trichloroethylene , 1
Aerated Static Pile Composting 3
Aerated Static Pile Composting 6
Biodecontamination of Fuel Oil Spills 8
Biodegradation 10
Biodegradation of Lube Oil Contaminated Soils 11
Biological Aqueous Treatment System 12
Bioremediation / Vacuum Extraction 13
Biotreatment Enhanced with Pact®/Wet Air Oxidation 14
Enhanced In Situ Biodegradation of Petroleum Hydrocarbons
in the Vadose Zone 16
Geolock / Bio-Drain Treatment Platform 17
In Situ Biodegradation 19
In Situ Biodegradation 20
In Situ Biological Treatment 22
In Situ Bioremediation Process 24
Liquid/Solid Contact Digestion 25
Submerged Aerobic Fixed-Film Reactor 26
TNT Slurry Reactor 27
U1/U2 Ground-Water Biological Treatment Demonstration 28
CHEMICAL TREATMENT
Chemical Detoxification of Chlorinated Aromatic Compounds 29
Chemical Oxidation/Cyanide Destruction 31
Combined Chemical Binding / Precipitation and
Physical Separation of Radionuclides 32
THERMAL TREATMENT
Centrifugal Reactor 33
Circulating Bed Combustor 34
Desorption and Vapor Extraction System 35
Flame Reactor 37
Infrared Thermal Destruction 38
Low-Temperature Thermal Stripping 40
Low Temperature Thermal Treatment (LT3) 41
Pyretron® Oxygen Burner 44
Radio Frequency (RF) Thermal Soil Decontamination 46
Waste-to-Fuel Recycling 48
X*TRAX™ Low-Temperature Thermal Desorption 49
VAPOR EXTRACTION
Ground-Water Vapor Recovery System 51
In Situ Air Stripping with Horizontal Wells 52
In Situ Soil Venting 55
In Situ Soil Venting 57
In Situ Steam/Air Stripping Process 58
Integrated Vapor Extraction and Steam Vacuum Stripping 60
Terra Vac In Situ Vacuum Extraction 62
Vacuum-Induced Soil Venting 64
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Table of Contents (cont'd)
SOIL WASHING
BEST Solvent Extraction 65
Biogenesis Soil Cleaning Process 67
Biotrol Soil Washing System 68
Debris Washing System 70
Ghea Associates Process 72
Soil Treatment with Extraksol 74
Solvent Extraction 75
SOLIDIFICATION/STABILIZATION
Chemfix Solidification / Stabilization Process 77
IM-TECH Solidification / Stabilization Process 79
In Situ Solidification / Stabilization Process 81
Soil-Cement Mixing Wall (S.M.W.) 83
Solidification / Stabilization 84
Solidification / Stabilization with Silicate Compounds 85
Solidrtech Solidification / Stabilization Process 86
Stabilization with Lime 88
OTHER PHYSICAL TREATMENT
Carver-Greenfield Process for Extraction of Oily Waste 89
Catalytic Decontamination 90
Catalytic Ozone Oxidation 92
Chemtact™ Gaseous Waste Treatment 94
Freezing Separation 95
Geosafe Process 97
In Situ Vitrification 99
Membrane Microfiltration 101
Precipitation, Microfiltration, and Sludge Dewatering 103
Rotary Air Stripping 105
Treatment with Ultra Violet, Hydrogen Peroxide, and Ozone 107
Ultrafiltration 108
Ultraviolet Radiation / Oxidation ; 109
Wetlands-Based Treatment m
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PREFACE
This collection of abstracts, compiled by the Federal Remediation Technology Roundtable,
describes field demonstrations of innovative technologies to treat hazardous waste. The collection is
intended to be an information resource for hazardous waste site project managers for assessing the
availability and viability of innovative technologies for treating contaminated ground water, soils, and
sludge. It is also intended to assist government agencies coordinate ongoing hazardous waste
remediation technology research initiatives, particularly those sponsored by the U.S. Environmental
Protection Agency (EPA), the U.S. Department of Defense (DoD), and the U.S. Department of Energy
(DOE). Innovative technologies, for the purposes of this compendium, are defined as those technologies
for which detailed performance and cost data are not readily available.
The demonstrations contained herein have all been sponsored by EPA, DoD, and DOE. In total,
75 demonstrations in seven different technology categories are described. A matrix listing these
demonstrations, the type of contaminant, media that can be treated, and the treatment setting for each
innovative technology is provided in Exhibit 1 on page vii.
This document represents a starting point in the review of technologies available for application to
hazardous waste sites. This compendium should not be looked upon as a sole source for this information
- it does not represent all innovative technologies nor all technology demonstrations performed by these
agencies. Only Federally-sponsored studies and demonstrations that have tested innovative remedial
technologies with site specific wastes under realistic conditions as a part of a full-scale field demonstration
are included. Those studies included represent all that were provided to the Federal Remediation
Technology Roundtable at the time of publication. Information collection efforts are ongoing.
The enclosed abstracts were obtained from the following resources:
• U.S. Department of Energy and U.S. Air Force, Joint Technology Review Meeting on Soil and
Ground Water Remedial Technologies, The Hazardous Waste Remedial Actions Program, Air
Force Engineering Services Center, Office of Technology Development, Atlanta, Georgia,
February 6-8, 1990.
• U.S. Department of Defense, Installation Restoration and Hazardous Waste Control
Technologies, prepared for the U.S. Army Toxic and Hazardous Materials Agency by ITT
Research Institute, The National Institute for Petroleum Energy Research, Bartlesville,
Oklahoma, August 1990, (Report No. CETHA-TS-CR-90067).
• The Alternative Treatment Technology Information Center (ATTIC), sponsored by the U.S.
Environmental Protection Agency, Office of Environmental Engineering and Technology
Demonstration.
• U.S. Environmental Protection Agency, The Superfund Innovative Technology Evaluation (SITE)
Program: Technology Profiles, Office of Solid Waste and Emergency Response and Office
of Research and Development, Washington, DC, November 1990, (EPA/540/5-90/006).
The Federal Remediation Roundtable
This publication was prepared under the auspices of the Federal Remediation Technologies
Roundtable (Roundtable). This organization was created to establish a process for applied hazardous
waste site remediation technology information exchange, to consider cooperative efforts of mutual interest,
and to develop strategies and analyze remedial problems that will benefit from the application of
innovative technologies. The Roundtable is comprised of representatives from several Federal agencies:
Federal Remediation Technologies Roundtable
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Environmental Protection Agency, Technology Innovation Office (EPA/TIO)
The mission of the Technology Innovation Office (TIO) is to increase applications of innovative
treatment technology by government and industry to contaminated waste sites, soils, and ground
water. TIO intends to increase usage of innovative techniques by removing regulatory and
institutional impediments and providing richer technology and market information to targeted
audiences of Federal agencies, States, consulting engineering firms, responsible parties,
technology developers, and the investment community. The scope of the mission extends to
Superfund sites, corrective action sites under the Resource Conservation and Recovery Act (RCRA),
and underground storage tank clean-ups. By contrast, TIO is not a focus for EPA interest in
treatment technologies for industrial or municipal waste streams, for recycling, or for waste
minimization. I
Environmental Protection Agency, Office of Research and Development (EPA/ORD)
The Office of Research and Development (ORD) Superfund Innovative Technology Evaluation
(SITE) program supports development of technologies for assessing and treating waste from
Superfund sites. The SITE program was authorized by the Superfund Amendments and
Reauthorization Act of 1986 with the goal of identifying technologies, other than land disposal, that
are suitable for treating Superfund wastes. The program provides an opportunity for technology
developers to demonstrate their technology's capability to successfully process and remediate
Superfund waste. EPA evaluates the technology and provides an assessment of potential for future
use for Superfund cleanup actions. The SITE program has currently evaluated or supported
research efforts for more than 100 innovative treatment technologies. The SITE program is
administered by EPA's Risk Reduction Engineering Laboratory (RREL) in Cincinnati, Ohio.
Department of Defense (DoD), Defense Environmental Restoration Program (DERP)
The Office of the Secretary of Defense (OSD), operating through the Deputy Assistant
Secretary of Defense, Environment (DASD (E)), establishes policy and monitors the Armed Force's
execution of the DoD hazardous waste site cleanup program. The Defense Environmental
Restoration Program (DERP) funds activities at over 17,000 DoD sites located on nearly 1,700
properties through the Installation Restoration Program (IRP). The DoD works cooperatively with
the Environmental Protection Agency and the States toward the goal of taking timely, effective, and
efficient actions at all stages of the DERP. Research and development of better methods for site
investigation and cleanup is an important part of DERP. Many innovative technologies have been
developed and demonstrated to improve the speed and cost-effectiveness of DoD site cleanups.
U.S. Army Corps of Engineers
In support of the Army's Installation Restoration (IR) Program, the U.S. Army Corps of
Engineers has the responsibility of ensuring the development of necessary and improved
technology for conduct of the Program. The U.S. Army Corps of Engineers is also charged with
the responsibility for developing improved pollution abatement and environmental control
technology in support of the U.S. Army Material Command industrial complex (Pollution Abatement
or PAECT Program). The purpose of the IR Decontamination Development Program is to provide
R&D support to required assessment and cleanup actjons at Army installations. Efforts include
evaluating commercially available state-of-the-art technologies as well as developing new, innovative
technologies that are more economical and efficient than existing technology. The PAECT program
addresses waste minimization and disposal alternatives for the Army's industrial operations.
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U.S. Army Toxic and Hazardous Materials Agency (USATHAMA)
The U.S. Army Toxic and Hazardous Materials Agency (USATHAMA), a Field Operating
Activity (FOA) of the U.S. Army Corps of Engineers, is a major focal point in the program
management and support efforts of the Army-wide environmental program. With its principal focus
directed toward supporting the installation in achieving and maintaining environmental compliance,
the Agency's activities fall into five major categories:
Environmental Compliance;
-- Installation Restoration Program (IRP);
— Environmental Training and Awareness;
- Research and Development (R & D); and
Environmental Information Management.
U.S. Air Force/Engineering and Services Center (AFESC)
The Air Force Engineering and Services Center (AFESC) is responsible for identifying,
developing, and testing technologies that may be useful for remediating contaminated sites as part
of the Air Force's Installation Remediation Program.
U.S. Navy, Naval Energy and Environment Support Office (NEESA)
The Naval Energy and Environmental Support office (NEESA), in Port Hueneme, California,
provides technology transfer information to Navy and Marine Corps Installations with hazardous
waste cleanup responsibilities. NEESA wrote and periodically updates the Navy's Remedial Action
Technology Guide, which provides guidance to Navy commands on preview technologies including
cost data. NEESA is also involved in developing Remedial Action Contracts, which will be available
Navy-wide to implement cleanups. NEESA coordinates closely with the Navy Civil Engineering
Laboratory, in Port Hueneme, California, to match new R&D efforts to actual field sites in order to
test new technologies. The technology transfer mission extends to CERCLA actions, RCRA
corrective actions and UST cleanups/removals.
Department of Energy, Office of Technology Demonstration (DOE/OTD)
The Department of Energy's (DOE) Office of Technology Demonstration (OTD) was
established to identify technologies in the research and development and demonstration (RD&D)
stage, and to demonstrate, test, and evaluate those technologies that will provide DOE with
accelerated and/or improved methods for achieving its environmental goals as specified in its Five-
Year Plan.
Future Demonstrations
This publication will be updated on a periodic basis. If you will be conducting a demonstration
featuring an innovative hazardous waste treatment technology in the future, or if you are aware of any
project that is relevant to this collection, but has been omitted, please forward this information to TIO:
Daniel M. Powell
Environmental Protection Specialist
Technology Innovation Office
U.S. Environmental Protection Agency
401 M Street, SW, OS-110
Washington, DC 20460
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For your convenience, we have included, at the end of this volume, the Innovative Remedial
Technologies Information Collection Form to guide you in formatting the information for inclusion in this
compendium. The Roundtable developed this form as a model for use in collecting findings On innovative
technologies and their applications, effectiveness, and costs.
The form is intended to facilitate new data collection efforts and to indicate the data we are most
interested in capturing. If, however, you have already collected and recorded the information in an
alternative format, please feel free to forward any previously written abstract or summary. We will reformat
it to be included in this compendium.
If you have any comments on the usefulness and clarity of this publication, please complete the
suggestion form on the last page, and send it to Daniel Powell at the address listed above.
vi
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Exhibit 1
Matrix Showing the Various Technology/Contaminant/Media
Combinations Addressed within this Compendium
Solidification/Stabilization
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Bioremediation
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Bioremediation
Above-Ground Biological Treatment of Trichloroethylene
Trichloroethylene (TCE) in Ground Water
Technology Description
In this treatment, methane-degrading bacteria
co-metabolize short-chain, chlorinated aliphatic
hydrocarbons. This technology is applicable to
the removal of short chain (C1 and C2)
chlorinated aliphatic hydrocarbons from water.
It can be used as an above-ground "pump and
treat" method of treating contaminated ground
water. Other applications can include in situ
decontamination or the removal of similar
compounds from any water stream.
An enzyme, a non-specific oxygenase that
metabolizes methane, attacks trichloroethylene
(TCE). The bacteria cannot, however, use TCE
as "food" but must have methane as a carbon
source. The reaction can take place in a
bioreactor or in situ. A mixture of oxygen and
methane is passed through the reactor or
reaction zone to sustain the microbial population.
The contaminated water is allowed to percolate
down through the bed. The packing material
can be soil, but care must be taken to avoid
plugging.
Technology Performance
A field pilot testing of this treatment was
conducted at Tinker Air Force Base, Oklahoma,
during 1989. Approximately 80 percent
destruction of TCE was achieved. Complete
biodegradation may be achieved with
lengthening of the reactor columns. Flow rate
for the contaminated water in this process is two
to three Lymin, with a retention time of 20 to 50
minutes in the reactor, depending upon the
packing material used. No hazardous
intermediate compounds are created with this
process.
Remediation Costs
Cost information is not available.
Contacts
Captain Catherine M. Vogel
HQ AFESC/RDVW
Tyndall AFB, Florida 32403-6001
904/ 283-4628
Autovon 523-4628/2942
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Roof
Concr«« pad (IS'Xayxa" thick)
2
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Bioremediation
Aerated Static Pile Composting
Explosives (TNT, RDX, HMX) in Lagoon Sediments
Technology Description
Composting is a process by which organic
materials are biodegraded by microorganisms,
resulting in the production of organic and
inorganic byproducts and energy in the form of
heat. This heat is trapped within the compost
matrix, leading to the self-heating phenomenon
known as composting. Composting is initiated
by mixing biodegradable organic matter
(explosives in this study), with organic carbon
sources and bulking agents, which are added to
enhance the porosity of the mixture to be
composted.
In "static pile" composting, an aeration/heat
removal system is utilized to increase process
control over the composting system. The
aeration/heat removal system typically takes the
form of a network of perforated pipe underlying
the compost pile. The pipe is attached to a
mechanical blower and air is periodically drawn
or forced through the compost to effect aeration
and heat removal.
The composting test facilities were constructed
of concrete test pads with runoff collection
systems and sumps, covered by a roof to
protect the compost piles from weather and to
minimize the amount of moisture collected in the
sump. Bulking agents and carbon sources
consisted of horse manure, alfalfa, straw, fertilizer
and horse feed. Baled straw was used to
contain the pile contents, and was arranged in a
ring around the perimeter of each pile. Sawdust
and hardwood mulch were used to construct the
pile bases, provide additional bulking material,
and insulate the piles. After mixing, the compost
was transported to the composting pads. Each
compost pile contained a system of pipes
connected to a blower, as described above. A
cross-sectional schematic diagram of a compost
pile is provided.
Technology Performance
The primary objective of this study was to
evaluate the utility of aerated static pile
composting as a technology for remediating soils
and sediments contaminated with the explosives
TNT, HMX, RDX, and tetryl.
Secondary objectives included evaluating the
efficacy of thermophilic (55°C) versus mesophilic
(35°C) composting, evaluating different materials
handling and process control strategies, and
determining transformation products when
Standard Analytical Reference Materials (SARMs)
were available.
Temperature was the primary test variable
investigated. The temperature of one set of
compost piles was kept within the mesophilic
range; the temperature of the second set of piles
was kept in the thermophilic range. The initial
concentration of explosives in test sediments
collected from the lagoon was 17,000 mg/kg.
Phase I,(piles 1 and 2) was conducted with a
mixture of lagoon sediments, sawdust, wood
chips, and a straw/manure mixture. Based on
data received from phase I, phase II (piles 3 and
4) added alfalfa and horse feed to the compost
mixture to increase the concentration of
biodegradable organic carbon in the compost
mixture. After 153 days of composting, the
sblvent-extractable total explosives were reduced
to 376 mg/kg and 74 mg/kg in the mesophilic
and thermophilic piles, respectively. The mean
percent reductions of extractable TNT, RDX and
HMX were 99.6, 94.8, and 86.9 weight percent in
the mesophilic piles, and 99.9, 99.1, and 95.6
weight percent in the thermophilic piles.
The results of this field demonstration indicate
that composting is a feasible technology for
decontaminating explosives-contaminated soils
and sediments. Further investigation is
warranted for optimizing the materials balance
and soil loading rate for mixtures to be
composted, minimizing bulking agent used, and
developing a design and operation management
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plan for a full-scale composting facility. In
addition, the compost residue should be
subjected to a toxicity evaluation and more
extensively analyzed to determine the final fates
of HMX, RDX, TNT, and tetryl.
Remediation Costs
Cost information is not available.
General Site Information
This field-scale demonstration project was
conducted at the Louisiana Army Ammunitions
Plant (LAAP). Compost piles were constructed
and tested at LAAP between December 1987
and April 1988. Phase I piles were tested for 33
days; phase II piles were tested for 153 days.
Approximately 21 cubic yards of sediment was
excavated from Pink Water Lagoon No. 4 for use
in this study,
LAAP was built to load and pack ordinance for
the U.S. Army. Explosives have never been
manufactured at the facility, but are brought in
and utilized in loading, assembling, and packing
lines. Initially, the. area where the field
demonstration was conducted was used as a
burning grounds to dispose of out-of-
specification ordnance. These burning pits were
converted to lagoons in the mid-1940s. The
lagoons were used to dispose of wastewater
generated during wash down of the munitions
loading lines. Equipment used to load munitions
was washed with water, and the resulting
wastewater contained high concentrations of
suspended explosives ("pink water"). Pink water
was transported to the unlined lagoons and
dumped into individual lagoons via a concrete
spillway. Suspended explosives settled to the
bottom of the lagoons. Over the period of
approximately 30 years during which pink water
was disposed of in the lagoons, high
concentrations of explosives accumulated in the
upper sediment. The highest concentrations
(300,000-600,000 mg/kg) accumulated near the
spillways. In October 1984, the pink water
lagoon site at LAPP was proposed for inclusion
on the National Priority List (NPL).
Contacts
USATHAMA - Aberdeen Proving Grounds:
Gregory B. Mohrman - CETHA-TS-D
Aberdeen Proving Ground, Maryland 21010-5401
301/671-2054
Technology Developer Contacts:
Richard T. Williams - Section Manager
P. Scott Ziegenfuss - Project Scientist
Peter J. Marks - Project Manager i
Roy F. Weston, Inc.
One Weston Way
West Chester, Pennsylvania 19380
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Roof
Wood chip
cover and
base
Concrete pad (18'X30'X8" thick)
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Bioremediation
Aerated Static Pile Composting
Propellants (Nitrocellulose) in Soil and Sediments
Technology Description
Composting is a process by which organic
materials are biodegraded by microorganisms,
resulting in the production of organic and
inorganic byproducts and energy in the form of
heat. This heat is trapped within the compost
matrix, leading to the self-heating phenomenon
known as composting. Composting is initiated
by mixing biodegradable organic matter
(nitrocellulose (NC) in this study), with organic
carbon sources and bulking agents, which are
added to enhance the porosity of the mixture to
be composted.
In "static pile" composting, an aeration/heat
removal system is utilized to increase process
control over the composting system. The
aeration/heat removal system typically takes the
form of a network of perforated pipe underlying
the compost pile. The pipe is attached to a
mechanical blower and air is periodically drawn
or forced through the compost to effect aeration
and heat removal. The primary objective of
hazardous materials composting is to convert
hazardous substances into innocuous products
for ultimate disposal, such as land application.
The composting test facilities were constructed
of concrete test pads with runoff collection
systems and sumps, covered by a roof to
protect the compost piles from weather and to
minimize the amount of moisture collected in the
sump. Bulking agents and carbon sources
consisted of a cow manure slurry, alfalfa, straw,
and horse feed. Baled straw was used to
contain the pile contents, and was arranged in a
ring around the perimeter of each pile. Sawdust
and hardwood mulch were used to construct the
pile bases, provide additional bulking material,
and insulate the piles. After mixing, the compost
was transported to the composting pads. Each
compost pile contained a system of perforated
and non-perforated pipes connected to a blower.
The blowers were used to pull air through the
compost piles to promote aeration and remove
excess heat. A cross-sectional schematic
diagram of a compost pile is provided.
Technology Performance
The primary objective of this study was to
evaluate the utility of aerated static pile
composting as a technology for NC fine (out-of
specification NC) remediation and destruction of
soils contaminated with NC. Secondary
objectives included evaluating the efficacy of
thermophilic (55°C) versus mesophilic (35°C)
composting, determining a maximum soil loading
rate, and comparing different process control
and material handling strategies.
The test variable in compost piles 1 and 2
(phase I) was temperature. The temperature of
pile 1 was kept within the mesophilic range, and
the temperature of pile 2 was kept in the
thermophilic range. The concentration of NC in
test soils collected from the dredge basin were
18,800 mg/kg for phase I tests. After mixing,
total NC concentrations in pile 1 were 3,670
mg/kg, and concentrations in pile 2 were 3,608
mg/kg. After 152 days of the study, mean total
NC concentrations were 651 mg/kg and 54
mg/kg, respectively. Information concerning the
effect of temperature on the NC concentration
was inconclusive, however, because there were
apparent discrepancies in the starting data
gathered for pile 1.
The test variable in piles 3 and 4 (phase II) was
the degree of soil loading within each pile. The
initial soil loading was increased from 19 percent
in phase I to 22 percent in pile 3, and 32.5
percent in pile 4. The concentration of NC in
tests soils collected for phase II was 17,027
mg/kg. After mixing, the concentrations of NC in
pile 3 were 7,907 mg/kg, and. 13,086 mg/kg in
pile 4. After 112 days of the study, total mean
concentrations of NC were 30 mg/kg and 16
mg/kg, respectively. Both piles showed greater
than 99.5 percent reduction of NC from the
starting point of the test. These results suggest
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that successful composting will likely occur at
sediment loading rates of up to 50 percent or
exceeding 50 weight percent.
The results of this field demonstration indicate
that composting is a feasible technology for
reducing the extractable NC concentration in
contaminated soils. In addition, this study
provides tentative evidence indicating that NC
can be degraded when incorporated into a
mixture to be composted at a high
concentration. The fate of the NC could not be
determined; however, microbial degradation of
the likely process.
Remediation Costs
Cost information is not available.
General Site Information
This field-scale demonstration project was
conducted at the Badger Army Ammunitions
Plant (BAAP) in Sauk County, Wisconsin. Four
compost piles were constructed at BAAP during
the period from April 1988 to January 1989. The
first set of compost piles was tested for 151
days; the second set was tested for 112 days.
Approximately 13 cubic yards of test soils were
excavated from Dredge Spoil Basin No. 1 for use
in this study.
Constructed in 1942, the plant operated
intermittently over a 33-year period, producing
single- and double-base propellants for rocket,
cannon, and small arms ammunition. During the
plant's period of active operation, various
chemical materials were produced, and the
associated wastes and manufacturing
byproducts were disposed on-site. The wastes
included acids, nitroglycerin, and nitrocellulose
(NC). As a result of the disposal practices,
contamination of soils, the underlying aquifer,
and, to some extent, surface waters have
occurred.
Contacts
USATHAMA - Aberdeen Proving Grounds:
Wayne Sisk - CETHA-TS-D
Aberdeen Proving Ground, Maryland 21010-5401
301/671-2054
Technology Developer Contacts:
Richard T. Williams - Section Manager
P. Scott Ziegenfuss - Project Scientist
Peter J. Marks - Project Manager
Roy F. Weston, Inc. ,
One Weston Way
West Chester, Pennsylvania 19380
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Bioremediation
Biodecontamination of Fuel Oil Spills
Fuel Oil in Soil
Technology Description
In this treatment, biodegradation is
accomplished by applying special oil-degrading
bacteria to a bioreactor while filling the reactor
with leachate water. As the reactor overflows,
bacteria are carried to a spray field sump and
then to injection wells and the spray field.
Surface sprayers apply the treated leachate
water on the spray field while the injection wells
apply the treated leachate water to soil under the
buildings. As more water is added to the system
and the ground under the buildings, the
contaminated area becomes saturated. Run-off
water along with leachate water is collected in a
trench down-slope from the contaminated area.
The collected water is pumped back to the
aerated reactor where bacterial growth on the
high surface area matrix, on which some of the
bacteria are immobilized, occurs. Clean
nutrient-, detergent-, and oxygen-enriched water
with bacteria is recirculated to the spray field
and injection wells.
Technology Performance
The microorganisms function best
temperatures between 20° and 35° C.
at
Remediation Costs
The site was cleaned to a satisfactory level for
approximately $37,000, not including shipping
the equipment to the site, installation labor
supplied by facility personnel, and analytical
costs.
General Site Information
This method was implemented to clean up a fuel
oil spill resulting from leaking pipes at a Naval
Communication Station atThurso, Scotland. The
contaminated area had a considerable slope,
and the contaminated soil was a thin layer over
a relatively impermeable rock substrate. In this
case, oil was entrapped in the soil matrix
beneath boiler and power buildings, an area
approximately 800 m . The project lasted from
February to October 1985.
Contact
Deh Bin Chan, Ph.D.
Environmental Protection Division, Code L71
Naval Civil Engineering Laboratory
Port Hueneme, California 93043-5003
805/982-4191
Autovon 551-4191
8
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NUTRIENTS
LEACHATE COLLECITON PUMP—*-[l
BIOREACTOR I
DETERGENT
SPRAY FIELD PUMF
INJECTION
WELLS
LEACHATE
SPRAY FIELD SYSTEM COLLECTION
TRENCH
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Bioremediation
Biodegradation
TCE in Soil and Ground Water
Technology Description
This biodegradation process has two phases: (1)
use of pump and treat bioreactors to degrade
trichloroethylene (TCE) and polychloroethylene
(PCE) in ground water and (2) use of vegetation
to encourage a rhizosphere that can degrade
TCE and PCE in surface soil. The first phase
has three parts: isolating microbes from TCE-
contaminated soil that are capable of degrading
TCE and PCE in water; optimizing the
degradation capabilities of these microbe in
laboratory bioreactors; and building and testing
a pilot-scale (10 gpm) bioreactor at C&P Burning
Rubble Pits.
One benefit from this task is that large-scale
bioreactors can be used in various pump and
treat scenarios of ground water to remove both
TCE and other volatile and non-volatile organics.
Another benefit from this task is that whenever
organic chemicals contaminate surface soils,
selective vegetation and cultivation techniques
can be used to remediate the site in a very
aesthetic and cost effective manner.
Technology Performance
This process was recently tested at DOE's
Savannah River site. The results from the first
task were positive:
• Bacteria was isolated from native soil that
can aerobically degrade TCE;
• Propane or methane was found to
stimulate TCE degradation more than
several other electron donors;
• Fluidized expanded bed bioreactors, using
propane or methane as a primary energy
source, were 99 percent and 50 percent
efficient in reducing TCE concentrations in
water, respectively; and
• Other wastes were also degraded when
mixed wastes were used in the reactor.
The results from the second task were also
positive:
• Vegetated soil was demonstrated to
oxidize TCE-contaminated soil faster than
unvegetated soil or sterilized soil at the
Miscellaneous Chemical Basin;
• Vegetation analysis showed ho difference
with normal vegetation succession for the
area;
• Four of the dominant plants at the test site
were compared and found to have
significantly different abilities to encourage
TCE degradation; and
• Phospholipid fatty acid analysis of the
rhizosphere defined the physiological
state of rhizosphere microbes.
Remediation Costs
Cost information is not available.
General Site Information
Biodegradation technology was : tested at
Savannah River Site, Miscellaneous Chemical
Basin, and C&P Burning Rubble Pits to remove
TCE from soil and ground water.
Contacts
Terry C. Hazen
Westinghouse Savannah River Company
Savannah River Laboratory
Environmental Sciences Section
Aiken, South Carolina 29802
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Federal Remediation Technologies Roundtable
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Bioremediation
Biodegradation of Lube Oil Contaminated Soils
Motor Oil in Soil
Technology Description
This treatment process requires the addition of
inoculant and nutrients to the contaminated soils
during disking. (The nutrients in the pilot studies
have consisted of sodium acetate, minerals
(potassium, magnesium, ammonium, phosphate,
and sulfate ions), and Tween 80, a surfactant.)
Afterward, the site is covered with plastic
sheeting. The plastic sheeting must have holes
to allow the transport of air.
This method is applicable for oil spills at
maintenance facilities, air strips, along roadways
and streets, and parking lots. Although research
on the method has been directed to degradation
of used lubrication oil, it should be applicable to
almost any nonfunctionalized aliphatic
hydrocarbon.
Technology Performance
A small-scale pilot test has been conducted at
the U.S. Army Construction Engineering
Laboratory in Champaign, Illinois. Noticeable
reduction in contaminant concentrations were
evident after four to six weeks. Pilot plots
consisted of plastic tubs containing eight
kilograms of contaminated soil placed outside
and covered with plastic. Flask tests were
conducted initially to identify optimum conditions.
Remediation Costs
Cost information is not available.
Contacts
Jean Donnelly
U.S. Army Construction Engineering Research
Laboratory
P.O. Box 4005
Champaign, Illinois 61820
217/352-6511
Federal Remediation Technologies Roundtable
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Bioremediation
Biological Aqueous Treatment System
Organic Compounds in Ground Water and Process Water
Technology Description
The Biotro! Aqueous Treatment System (BATS)
is a patented biological treatment system that is
effective for treating ground water and process
water contaminated by pentachlorophenol,
creosote components, gasoline and fuel oil
components, chlorinated hydrocarbons,
phenolics, or solvents. Other potential target
waste streams include coal tar residues and
organic pesticides. The technology may also be
effective for treating certain inorganic
compounds such as nitrates; however, this
application has not yet been demonstrated. The
system does not treat metals.
The BATS system uses an amended microbial
mixture, i.e., a microbial population indigenous to
the wastewater to which a specific
microorganism has been added. This system
removes the target contaminants as well as the
naturally occurring background organics.
Contaminated water enters a mix tank, where the
pH is adjusted and inorganic nutrients are
added. If necessary, the water is heated to an
optimum temperature, using a heat exchanger to
minimize energy costs. The water then flows to
the reactor, where the contaminants are
biodegraded.
The microorganisms, which perform the
degradation, are immobilized in a three-cell,
submerged, fixed-film bioreactor. Each cell is
filled with a highly porous packing material to
which the microbes adhere. For aerobic
conditions, air is supplied by fine bubble
membrane diffusers mounted at the bottom of
each cell. The system may also run under
anaerobic conditions.
As the water flows through the bioreactor, the
contaminants are degraded to carbon dioxide,
water, and chloride ion. The resulting effluent
may be discharged to a publicly owned
treatment works (POTW) or may be reused on-
site. In some cases, discharge with a National
Pollutant Discharge Elimination System (NPDES)
permit may be possible.
Technology Performance
In 1986-87, Biotrol performed a successful nine-
month pilot field test of BATS at a wood
preserving facility. Since that time, several other
demonstrations and commercial installations
have been completed. In 1989, EPA conducted
a SITE demonstration of the BATS technology at
the MacGillis and Gibbs Superfund site in New
Brighton, Minnesota, in which the system was
operated continuously for six weeks at three
different flow rates. Results from the
demonstration showed that PCP was reduced to
less than one ppm at all flow rates. Removal
percentage was as high as 97 percent at the
lowest flow rate. EPA released the Technology
Evaluation Report in December 1990.
Remediation Costs
Cost information is not available.
General Site Information
The SITE demonstration of the BATS technology
took place from July 24 to September 1,1989 at
the MacGillis and Gibbs Superfund site in New
Brighton, Minnesota.
Contacts
EPA Project Manager:
Mary K. Stinson
U.S. EPA
Risk Reduction Engineering Laboratory
Woodbridge Avenue
Edison, New Jersey 08837
908/321-6683
FTS: 340-6683
Technology Developer Contact:
John K. Sheldon
BioTrol, Inc.
11 Peavey Road
Chaska, Minnesota 55318
612/448-2515
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Federal Remediation Technologies Roundtable
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Bioremediation
Bioremediation / Vacuum Extraction
Petroleum Fuels in Soil
Technology Description
The bioremediation/vacuum extraction process
decontaminates soils that have been
contaminated with fuels by removing the
contaminated soil and stockpiling it for treatment.
This technology can be applied to soils
contaminated with diesel, JP5, or other fuels that
have leaked from underground storage tanks.
In order to decontaminate the stockpiled soil, it
is processed through a screen to eliminate rocks
greater than four inches in diameter. The
screened soil is transported to a site that is
protected by a 40-millileter liner with eight inches
of sand base. Three feet of contaminated soil is
spread along the base of the prepared pile and
then a series of vacuum extraction pipes are
trenched in the soil and connected to the
Vacuum Extraction System (VES) blower. The
VES blower provides movement of oxygen
through the pile. The remaining soil is piled into
a trapezoid shape about 15 feet high, 200 feet
long, and 60 feet wide. Fertilizer is added, and
an irrigation system is installed. Computer-
controlled sensors are placed within the pile to
monitortemperature, pressure, and soil moisture.
Technology Performance
The field pilot test conducted in Bridgeport,
California, showed two results:
After approximately two months of
operation, the average concentration of
total petroleum hydrocarbons (TPH) is 120
ppm; and
The Navy declared the tested site was
"clean" in a report prepared for the
California Regional Water Quality Control
Board.
Remediation Costs
Remediation costs are estimated at
approximately $80 per ton of soil at the
Bridgeport, California, pilot project.
General Site Information
A field pilot test was conducted at Bridgeport,
California in fiscal year 1989. Full-scale
implementation at the 29 Palms, California, MC
Air Ground Combat Center is anticipated.
Contacts
Denise Barnes
NCEL Code L71
Port Hueneme, California 93043
805/982-1651
Federal Remediation Technologies Roundtable
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u
Bioremediation
Biotreatment Enhanced with Pact®/Wet Air Oxidation
Organic Contaminants in Wastewater
Technology Description
This technology is applicable to municipal and
industrial wastewaters, as well as ground water
and leaehates containing hazardous organic
pollutants. This treatment system combines two
technologies: the PACT® treatment system and
wet air oxidation (WAO). The PACT® system
uses powdered activated carbon (PAC)
combined with conventional biological treatment
(e.g., an activated sludge system) to treat liquid
waste containing toxic organic contaminants.
The WAO technology can regenerate the PAC
for reuse in the PACT® system. The system is
mobile and can treat from 2,500 to 10,000
gallons of wastewater per day. Larger stationary
systems, treating up to 53 million gallons per
day, are already in operation. In the PACT®
system, organic contaminants are removed
through biodegradation and adsorption. Living
microorganisms (biomass) in the activated
sludge system are contained in liquid
suspension in an aerated basin. This biomass
removes biodegradable toxic organic
compounds from the liquid waste. PAC is added
to enhance this biological treatment by
adsorbing toxic organic compounds.
The degree of treatment achieved by the PACT®
system depends on the influent waste
characteristics and the system's operating
parameters. Important waste characteristics
include biodegradability, absorbability, and
concentrations of toxic organic compounds and
inorganic compounds, such as heavy metals.
Major operating parameters include carbon
dose, hydraulic retention time of the aeration
basin, solids retention time of the biomass-
carbon mixture, and biomass concentration in
the system. Liquid wastes fed into the PACT®
system should have sufficient nutrients (nitrogen
and phosphorous) and biodegradable
compounds to support the growth of active
biomass in the aeration basin. The temperature
of the waste should be in the range of 40° F to
100° F, and the influent pH should be in the
range of six to nine. Solids retention times affect
both the concentration and type of biomass in
the system; these vary from two days to 50 days.
Hydraulic retention times affect the degree of
biodegradation achieved and typically range
from two hours to 24 hours for relatively dilute
wastes, such as contaminated ground water,
and up to several days for concentrated wastes
and leachate. Carbon doses vary widely,
depending on the biodegradability and
adsorptive characteristics of the contaminants in
the waste. Higher PAC concentrations improve
the settleability of the PAC-biomass mixture and
reduce air stripping of volatile organic
contaminants.
Excess solids (PAC with adsorbed organics,
biomass, and inert solids) are removed
periodically from the system through the
system's clarifier (settling tank) or thickener (see
Figure 1). These excess solids are routed to the
WAO system reactor to regenerate the spent
PAC and destroy organics remaining in the
biomass. Temperatures and pressures in the
WAO system will be about •
480° F and 800 to 850 pounds per square inch,
respectively. After treatment in the WAO system,
the regenerated PAC may be separated from the
ash formed from destruction of the biomass and
returned to the aeration basin for reuse.
Technology Performance
The PACT® system has successfully treated a
variety of industrial wastewaters, including
chemical plant wastewaters, dye production
wastewaters, pharmaceutical wastewaters,
refinery wastewaters, and synthetic fuels
wastewaters, in addition to contaminated ground
water and mixed industrial/municipal wastewater.
In general, the PACT® system can treat liquid
wastes containing wide ranges of biochemical
oxygen demand (BOD), from 10 to 30,000 parts
per million (ppm), and chemical oxygen demand
(COD), from 20 to 60,000 ppm. Toxic volatile
organic compounds can be treated up to the
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Federal Remediation Technologies Roundtable
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level where they interfere with biomass growth,
about 1,000 ppm. Treatability studies have
shown that the PACT system can reduce the
organics in contaminated ground water from
several hundred ppm to below detection limits
(parts per billion range).
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
John F. Martin
U.S. EPA
! Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7758
FTS: 684-7758
Technology Developer Contact:
William M. Copa
Zimpro/Passavant Inc.
301 West Military Road
Rothschild, Wisconsin 54474
715/359-7211
Federal Remediation Technologies Roundtable
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Bioremediation
Enhanced In Situ Biodegradation of Petroleum Hydrocarbons
in the Vadose Zone
Petroleum Hydrocarbons in Unsaturated Soil
Technology Description
This enhanced in situ biodegradation process is
a modification of soil venting technology and
treats unsaturated soils contaminated with
petroleum hydrocarbons. This technology can
be applied to JP-4 fuels in the vadose zone.
Bioventing technology modifies the soil venting
process. Soil venting introduces large volumes
of air into the soil, providing oxygen needed to
enhance the biodegradation of hydrocarbon
contaminants. Bioventing uses soil venting
coupled with nutrient and moisture
augmentation.
This technology has a number of benefits:
• A large amount of volatile organics can be
removed from unsaturated soil without
destroying the remaining soil;
• The contaminants are merely transferred
from one phase to another and the soil
venting off-gas will probably require
further treatment;
• By modifying soil venting rates in
conjunction with supplying nutrients and
moisture to the subsurface, the in situ
biodegradation of the fuel components will
be enhanced; and
• This process will provide complete
destruction of a large portion of the in situ
contaminants and minimize the amount of
off gas requiring additional treatment.
This technology, however, is limited to
treating soil in the unsaturated zone.
Technology Performance
The pilot-scale field test was successful:
• Under optimum conditions, approximately
80 percent hydrocarbon removal was
achieved;
• Biodegradation removal rates ranged from
two to 20 mg/kg of soil per day. The
stabilized value averaged five mg/kg of
soil per day; and
• The system was not operated long
enough to determine the lower level of
treatment that could be achieved.
Remediation Costs
Remediation costs are estimated at
approximately $12-$15 per cubic yard of soil.
This estimate assumes no off-gas treatment will
be required.
General Site Information
A pilot-scale field test was conducted at POL
Area B at Tyndall Air Force Base, Florida,
between July 1989 and August 1990. This field
study only involved four small treatment plots,
approximately twenty feet by six feet by five feet
deep. The site was previously used as a JP4 jet
fuel storage area.
Contacts
/
Dr. Rob Hinchee
Battelle Columbus
Columbus, Ohio
614/424-4698
Captain Catherine Vogel
Project Officer
HQ AFEC/RODW
Tyndall AFB, Florida 32403
904/283-6036
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Federal Remediation Technologies Roundtable
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ft \
Bioremediation
Geolock / Bio-Drain Treatment Platform
Biodegradable Contaminants in Soils
Technology Description
The Geolock/Bio-Drain treatment platform is a
bioremediation system that is installed in the soil
or waste matrix. All types and concentrations of
biodegradable contaminants can be treated by
this system. Through direct degradation or
cometabolism, microorganisms can degrade
most organic substances. This technology can
be adapted to the soil characteristics of the area,
the concentration of contaminants, and geologic
formations. The system is composed of an in
situ tank, an application system, and a bottom
water recovery system.
The tank, an in situ structure, is composed of
high density polyethylene (HOPE), sometimes in
conjunction with a slurry wall. An underlying
permeable waterbearing zone facilitates the
creation of ingradient water flow conditions. The
tank defines the treatment area, minimizes in-
trusion of off-site clean water, minimizes the
potential for release of bacterial cultures to the
aquifer, and keeps contaminant concentration at
levels that facilitate treatment. The ingradient
conditions also facilitate reverse leaching or soil
washing. The application system, called Bio-
Drain, is installed within the treatment area. Bio-
Drain delivers bacterial cultures, nutrients, and
oxygen or any other proprietary chemical to the
soil profile. Bio-Drain acts to aerate the soil
column and any standing water. This creates an
aerobic environment in the air pore spaces of
the soil. The cost of installation is low, and Bio-
Drains can be placed in very dense
configurations.
Existing wells or new wells are used to create
the water recovery system for removal of con-
taminated soil washing water. By controlling the
water levels within the tank, reverse leaching or
soil washing and the volume of off-site clean
water entering the system can be controlled and
minimized. This minimizes the potential for off-
migration. It also creates a condition such that
the direction of existing contaminants and bac-
terial degradation products is toward the surface.
Conventional biological treatment is limited by
the depth of soil aeration, the need for physical
stripping, or the need to relocate the
contaminated media to an aboveground
treatment system. The Geolock/Bio-Drain
treatment platform surpasses these limitations as
well as reduces or eliminates the health risks
associated with excavation and air releases from
other treatment, technologies. Extremely dense
clays may be difficult to treat with this
technology. Rock shelves or boulders may
render installation impossible.
Technology Performance
EPA accepted this technology into the SITE
Demonstration Program in August 1990. EPA
began preparation of the Quality Assurance
Project Plan and site selection.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Randy Parker
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7271
FTS: 684-7271
Technology Developer Contact:
Lynn D. Sherman
YWC Midwest and IET
6490 Premier Avenue, N.W.
North Canton, Ohio 44720
216/499-8181
Federal Remediation Technologies Roundtable
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Geolock
E-XI Oxyien (H^K:J3 Otjita hS
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Federal Remediation Technologies Roundtable
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Bioremediation
In Situ Biodegradation
Fuels, Fuel Oils and Nonhalogenated Solvents in Soil and Ground Water
Technology Description
This in situ biodegradation process treats soil or
ground water contaminated with hydrocarbons
such as fuels, fuel oils, and nonhalogenated
solvents. This technology can be applied to fuel
spills, leaky storage tanks, and fire training pits.
Nutrients (especially nitrogen and phosphorus),
soil-conditioning chemicals, and hydrogen
peroxide are introduced through infiltration wells,
ditches, or soil surface irrigation. Pumping wells
remove excess fluids or contaminated ground
water. Contaminated water can be treated on
the surface or reinjected for treatment in the soil.
Monitoring wells must be placed within and
surrounding the site. Increased fluid throughput
might be accomplished by surface spray
irrigation techniques. Stoichiometrically, three
pounds of oxygen delivered in the hydrogen
peroxide is required for each pound of
hydrocarbon treated. In practice, more oxygen
will be required to satisfy other demands, such
as the oxidation of iron.
Technology Performance
Results from testing this technology at Kelly Air
Force Base, Texas, were negative:
• Degradation of petroleum hydrocarbons
was indicated;
• Although biodegradation of these
compounds by indigenous bacteria had
been demonstrated in laboratory scale
microcosms under anaerobic and aerobic
conditions respectively, this site was not
ideal for this method;
• Injection wells became clogged from
precipitation of calcium phosphate, which
reduced their injection capacity by 90
percent; and
This test showed that the design of
hydraulic delivery systems and the
compatibility of injection chemicals with
soil minerals is as important to successful
treatment as enhancement of bacteria.
Remediation Costs
Exclusive of site characterization, one estimate of
the cost range of this method is from $100 to
$200 per ton of contaminated soil. Monitoring
could be expensive, depending upon the type of
contaminant. Site characterization must be done
to determine soil/chemical compatibility. Another
estimate is that a nonresearch project would
cost between $230 and $300 per gallon of
residual fuel in the soil.
General Site Information
A large-scale pilot field test was conducted at
Kelly Air Force Base, Texas, from May 1985 to
February 1986. A large-scale pilot test is
planned for a tank farm at the Naval Air Station,
Patuxent River, Maryland.
Contacts
Captains Edward Heyse and Doug Downey
HQ AFESC/RDV
Tyndali AFB, Florida 32403
904/283-2942
Autovon 523-2942
Ron Hoeppel
NCEL
Environmental Protection Division
Port Hueneme, California 93043
805/982-1655
Federal Remediation Technologies Roundtable
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Bioremediation
In Situ Biodegradation
Organic Compounds in Soil
Technology Description
This in situ biodegradation process reclaims
contaminated soil in-place. It can be applied to
organic compounds released from fuel spills,
leaky storage tanks, fire training pits, and other
contaminant sources.
In situ biodegradation involves the enhancement
of environmental conditions that facilitate
biodegradation of organic contaminants by
native or exotic soil or sediment microorganisms.
Aerobic degradation is normally the most
efficient means by which microorganisms break
down organic contaminants. Direct exposure to
the atmosphere is one means to provide aerobic
conditions for in situ biodegradation. For
flooded or poorly drained soils or subsurface
soils, it may not always be possible to provide
direct exposure to atmospheric oxygen without
improving drainage. In such situations, in situ
biodegradation can be enhanced by providing
alternate electron acceptors, such as nitrate or
hydrogen peroxide, to the system. The
efficiency of in situ biodegradation enhancement
procedures can be tested in laboratory reactors
before scale-up for field application is carried
out.
Nutrients (especially nitrogen and phosphorus),
soil-conditioning chemicals, and hydrogen
peroxide can be introduced through infiltration
wells, ditches, or soil surface irrigation. Another
source of oxygen for aerobic biodegradation
may be fresh air introduced during the process
of soil venting for remediation of volatile organic
compounds (VOCs) from the soil. Pumping
wells remove excess fluids or contaminated
ground water. Contaminated water can be
treated on the surface or reinjected for treatment
In the soil. Monitoring wells must be placed
within and surrounding the site. Water
requirements can be met by surface spray
irrigation techniques. Although every pound of
hydrocarbon contaminant requires about 10
pounds of molecular oxygen for complete
degradation, in practice, more oxygen will be
required to satisfy other demands, such as
oxidation of iron.
This technology has numerous advantages:
• Excavation is not required;
• Resulting products are not toxic;
• Contaminant concentrations are reported
to have been reduced by bacteria to less
than one ppm; and
• Theoretically, in situ treatment of
contaminated soil can be accomplished
faster than the long-term flushing required
for surface-based water treatment.
In situ biodegradation, however, also has
limitations:
• High calcium, magnesium, or iron
concentrations in the soils and plugging
and loss of soil permeability limit the
effectiveness of the method;
• The method currently is limited primariiy to
sandy soils having a hydraulic
conductivity of at least 0.0001 cm/sec;
• Some mobilization of heavy metals can
occur;
• Applicability is site-specific;
• Considerable oxygen is required; and
• Daily maintenance might be necessary if
hydrogen peroxide is in the lines and
pumps and if special metals are not used.
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Federal Remediation Technologies Roundtable
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Technology Performance
Results from preliminary full-scale testing at Eglin
Air Force Base, Florida, were negative:
• After 15 months of operation at this site, it
was concluded that using hydrogen
peroxide as an oxygen source for
biodegradation has limitations which could
restrict its successful application to
relatively few Air Force sites.
Results from a large-scale pilot field test at Kelly
Air Force Base, Texas, were mixed:
• Degradation of petroleum hydrocarbons
was indicated;
• The site was not ideal for this method;
• Injection wells became clogged from
precipitation of calcium phosphate, which
reduced their injection capacity by 90
percent; and
• Design of hydraulic delivery systems and
compatibility of injection chemicals with
soil minerals is as important to successful
treatment as enhancement of bacteria.
Remediation Costs
The cost varies depending on site-specific
conditions. Exclusive of site characterization,
one estimate of the cost range for this method is
from $100 to $200 per ton of contaminated soil.
Monitoring could be expensive, depending upon
the type of contaminant. Site characterization
must be done to determine soil/chemical
compatibility. Another estimate is that a
nonresearch project would cost between $230
and $300 per gallon of residual fuel in the soil.
General Site Information
This method was implemented at Eglin Air Force
Base, Florida, starting in November 1986. Full-
scale implementation began in early summer of
1987. In addition, a large-scale pilot field test
was conducted at Kelly Air Force Base, Texas,
from May 1985 to February 1986. The
Waterways Experiment Station (WES) currently
is assisting the US Navy in evaluation of
anaerobic in situ biodegradation for cleanup of
a gasoline spill from an underground tank
located in a wetland area.
Contacts
Ron Hoeppel
NCEL, Code L71
Port Hueneme, California 93043
805/982-1651
Captain Ed Marchand
HQ AFESC/RDVW
Tyndall AFB, Florida 32403-6001
DSN 523-6023
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Bioremediation
In Situ Biological Treatment
Organic Constituents in Soil, Sediment, Sludge, and Water
Technology Description
Biological processes can be applied to water,
soil, sludge, sediment, and other types of
materials contaminated with organic
constituents. This bioremediation technology is
designed to biodegrade chlorinated and non-
chlorinated organic contaminants by employing
aerobic bacteria that use the contaminants as
their carbon source. This proposed technology
has two configurations: in situ biotreatment of
soil and water; and on-site bioreactor treatment
of contaminated ground water.
A primary advantage of in situ bioremediation is
that contaminants in subsurface soils and
ground water can be treated without excavating
overlying soil. This technology uses special
strains of cultured bacteria and naturally
occurring microorganisms in on-site soils and
ground water. Because the treatment process is
aerobic, oxygen and soluble forms of mineral
nutrients must be introduced throughout the
saturated zone. The end products of the aerobic
biodegradation are carbon dioxide, water, and
bacterial biomass. (This system must be
engineered to maintain parameters such as pH,
temperature, and dissolved oxygen (if the
process is aerobic), within ranges conducive to
the desired microbial activity.)
Contaminated ground water can also be
recovered and treated in an aboveground
bioreactor. Nutrients and oxygen can then be
added to some or all of the treated water, and
the water can be recycled through the soils as
part of the in situ soil treatment.
Because site-specific environments influence
biological treatment, all chemical, physical, and
microbiological factors are designed into the
treatment system. Subsurface soil and ground-
water samples collected from a site are analyzed
for baseline parameters, such as volatile
organics, metals, pH, total organic carbon, types
and quantities of microorganisms, and nutrients.
A treatability study, which includes flask and
column studies, determines the effects of
process parameters on system performance.
The flask studies test biodegradation under
optimum conditions, and the column studies test
the three field applications: (1) soil flushing;
(2) in situ biotreatment, and (3) in situ
biotreatment using ground water treated in a
bioreactor.
Technology Performance
The planned demonstration of this technology on
a wide range of toxic organic compounds was
canceled after the completion of treatability
studies in April 1990. EPA released the
treatability study report in January 1991.
Although the demonstration was canceled at the
first site, the technology may be demonstrated at
another hazardous waste site in the future.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Naomi P. Barkley
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7854
FTS: 684-7854
Technology Developer Contact:
Michael Nelson
Ecova Corporation
3820 159th Avenue Northeast
Redmond, Washington 98052
206/883-1900
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Federal Remediation Technologies Roundtable
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Microbes, nutrients
oxygen source
Biological
Treatment
Makeup
water
Clarlfler
Bloreactor
Recharge
Recovery
Federal Remediation Technologies Roundtable
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C3
Bioremediation
In Situ Bioremediation Process
Volatile Organics in Soil
Technology Description
This in situ bioremediation process increases the
quality and acceleration of biodegradation in
contaminated soils. Different contaminants may
have different degrees of success. High
concentrations of heavy metals, non-
biodegradabletoxicorganics, alkaline conditions,
or acid conditions could interfere with the
degradation process. Although volatiles may
volatilize during remediation, volatilization has
been minimized by adding a hood around the
auger assembly and treating the captured
gases. The Dual Auger System was also
developed for the treatment of inorganic
contaminated soils, by injecting reagent slurry
into the soil to solidify/stabilize contaminated
waste.
This in situ bioremediation process uses a
specialized equipment system to inject site-
specific microorganism mixtures, along with the
required nutrients, and homogeneously mix them
into the contaminated soils. The injection and
mixing process effectively breaks down fluid and
soil strata barriers, and eliminates pockets of
contaminated soil that would otherwise remain
untreated.
The process uses a twin, five-foot diameter
auger system powered and moved by a
standard backhoe. The auger drills into
contaminated soil with hollow shafts, allowing the
microorganism and nutrient mixture to pass.
The allocation of the microorganisms and
nutrients occurs during the initial auger action.
The auger flights break the soil loose, allowing
mixing blades to thoroughly blend the
microorganism and nutrient mixture with the soil.
This occurs in an overlapping manner to ensure
the complete treatment of all contaminated soil.
The mixing action is continued as the augers are
withdrawn. Treatment depth can exceed 100
feet. Water, nutrients, and bacteria are added to
the contaminant area as needed.
Technology Performance
EPA accepted this technology into the SITE
Program in June 1990 and is currently locating
a site to demonstrate this project.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Edward J. Opatken
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7855
FTS: 684-7855
Technology Developer Contact:
Richard P. Murray
In Situ Fixation Company
P.O. Box 516
Chandler, Arizona 85244-0516
602/821-0409
24
Federal Remediation Technologies Roundtable
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Biodegradation
Liquid/Solid Contact Digestion
Organic Materials in Soil and Sludge
Technology Description
Remediation Technologies (formerly Motec, Inc.)
has developed a liquid-solid contact digestion
(LSCD) process which biodegrades liquids,
sludges, and soils with high organic
concentrations. Specifically, this technology can
treat halogenated and nonhalogenated organic
compounds, including some pesticides and
herbicides. In this process, organic materials
and water are placed in a high energy
environment, in which acclimated
microorganisms biodegrade the organic
constituents.
The system consists of two or three portable
tank digesters or lagoons: (1) a primary contact
or mixing tank; (2) a primary digestion tank; and
(3) a polishing tank. Treatment may take ten
days or more, depending on the type and
concentration of the contaminants and the
temperature in the tanks.
In the primary contact tank, water is mixed with
influent sludge or soil. The mixing process is
designed to achieve a 20 to 25 percent solids
concentration. Water is obtained either from the
contaminated source or a fresh water source.
Emulsifying chemicals may be added and pH is
adjusted to increase the solubility of the organic
phase. After water is added, the batch mixture
is transferred to the primary digestion tank,
where acclimated seed bacteria are added and
aerobic biological oxidation is initiated. Most of
the biological oxidation occurs during this phase.
reached, the supernatant from the polishing tank
is recycled to the primary contact tank and
biological sludge is treated in prepared bed solid
phase bioreactors.
Technology Performance
This technology has not been demonstrated to
date. The developer is seeking private party co-
funding for a three- to four-month demonstration
on petroleum or coal tar-derived wastes.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Ronald Lewis
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7856
FTS: 684-7856
Technology Developer Contact:
Randy Kabrick
Remediation Technologies, Inc.
1301 West 25th Street, Suite 406
Austin, Texas 78759
512/477-8661
When the biodegradation reactions decrease
significantly, the batch mixture is transferred to
the polishing tank for final treatment. Once the
pH has been readjusted in the polishing cell, co-
metabolites and nutrients are added to maintain
and enhance the biomass. In this phase,
organic constituents are degraded to target
concentration levels. Because the system runs
on a negative water balance, water is added
throughout the process. Once target levels are
Federal Remediation Technologies Roundtable
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Bioremediation
Submerged Aerobic Fixed-Film Reactor
Biodegradable Materials in Liquid
Technology Description
This biological treatment system relies on
aerobic microbial processes to metabolize
contaminants present in a liquid waste stream.
This system can treat liquid waste containing low
concentrations (less than 20 ppm) of readily
biodegradablematerialsandyield concentrations
in the low parts per billion (ppb) range.
This technology is typically used to treat ground
water and industrial process waters, but is also
applicable to contaminated lagoon and/or pond
waters. The water to be treated must fall within
a pH of 6.5 to 8.5, a temperature of 60-90°F, and
be free of toxic and/or inhibitory metals. Readily
biodegradable compounds, such as methyl ethyl
ketone and benzene can be treated, along with
some organic chemicals that are initially more
resistant to biodegradation, such as
chlorobenzene. Halogenated compounds are
not readily biodegraded and cannot be treated
by this system.
This system consists of an above-ground fixed-
film reactor, supplemental nutrient storage tank
and pump, cartridge filter, and final activated-
carbon filter. High surface area plastic media is
used to fill the reactor and the water level within
the reactor is set to cover the plastic media.
Bacterial growth is attached as film to the
surface of the plastic media.
The bioreactor is operated on a one-pass,
continuous-flow basis at hydraulic retention times
as low as one hour. The process begins when
contaminated water from a well or equalization
tank is pumped into the bioreactor. The influent
waste stream is evenly dispersed over the
reactor packing by a header-distribution system.
As the waste stream passes through the reactor,
the biofilm removes the biodegradable organics.
An air distribution system below the plastic
media supplies oxygen to the bacteria in the
form of fine bubbles. An effluent water header
system collects water from the reactor after is
has been treated. Water exiting the reactor is
first passed through a cartridge filter, to remove
any excess biological solids, followed by
activated carbon treatment, to further remove
any remaining organic compounds. Depending
upon the effluent water discharge criteria, the
cartridge and carbon filters may not be needed.
Technology Performance
The demonstration for this treatment system is
expected to start in the spring or summer of
1991.
Remediation Costs
Cost information is not available. \
Contacts
EPA Project Manager:
Ronald Lewis :
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive i
Cincinnati, Ohio 45268
513/569-7856
FTS: 684-7856
Technology Developer Contact:
David Allen
Allied Signal Corporation
P.O. Box 1087R
Morristown, New York 07962
201/455-5595
26
Federal Remediation Technologies Roundtable
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Bioremediation
TNT Slurry Reactor
Explosives (TNT, RDX, HMX) in Soil
Technology Description
In this treatment, a slurry of TNT-contaminated
soils and water are bio-treated in a thoroughly
mixed environment. Loss transfer effects, as well
as biological conditions are controlled via mixing
rate, oxygen, and nutrient addition. Reactor
designs being considered include a knife blade
slurry reactor and rotary sequencing batch
reactors (SBRs). Work includes culture microbe
studies of TNT degraded using C14 tracers. This
treatment may be applied to soils contaminated
with TNT, RDX, HMX, and other potential wastes
associated with explosives.
Remediation Costs
Cost information is not available.
Contacts
Captain Craig Myler
USATHAMA
CETHA-TS-D
Aberdeen Proving Ground, Maryland 21010
(301) 671-2054
Technology Performance
A bench-scale study has been performed. A
demonstration and feasibility study was
scheduled at Argonne National Laboratory in
fiscal year (FY) 1990.
Federal Remediation Technologies Roundtable
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Bioremediation
U1/U2 Ground-Water Biological Treatment Demonstration
Nitrates and Organics in Ground Water and Wastewater
Treatment Description
This biological treatment system simultaneously
removes nitrates and organics from
contaminated aqueous streams. This
technology can be applied to ground water and
wastewater.
Biodenitrification is a technology for the
simultaneous removal of nitrates and organics
from contaminated aqueous streams. At
Hanford, the U1/U2 Groundwater Biological
Treatment Project will demonstrate a biological
process for simultaneous destruction of nitrates
and specific organic contaminants in Hanford
ground waters.
The treatment process uses facultative anaerobic
microorganisms isolated from the Hanford Site
that have been shown to degrade both nitrates
and carbon tetrachloride. These contaminants
have been identified in U1/U2 ground water from
the 200 West Area of the Hanford Site at levels
exceeding the drinking water standard.
Treatment Performance
Results from demonstrations at the Hanford Site
were positive:
• Based on tests with a simulated ground
water feed, greater than 99 percent of the
nitrates and 93 percent of the carbon
tetrachlorides were destroyed at influent
concentrations of 400 ppm and 200 ppb,
respectively; and
• Analysis of the product streams indicated
that the concentrations of nitrates and
carbon tetrachlorides were below the
drinking water standards of 44 ppm and 5
ppb, respectively.
Remediation Costs
Cost information is not available.
General Site Information
This process was demonstrated with a simulated
ground water feed in fiscal year (FY) 1989 and
will be demonstrated at the Hanford Site,
Washington, in FY 1991. Liquid wastes
containing radioactive, hazardous, and regulated
chemicals have been generated throughout the
40 years of operations on the Hanford Site.
Some of these wastes were discharged to the
soil column and many of the waste components,
including nitrates and carbon tetrachloride, have
been detected in the Hanford ground water.
Contacts
Thomas M. Brouns
Pacific Northwest Laboratory
P.O. Box 999, MSIN P7-44
Richland, Washington 99351
509/376-7855
(FTS) 444-7855
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Chemical Treatment
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Chemical Treatment
Chemical Detoxification of Chlorinated Aromatic Compounds
Dioxin and Herbicides in Soil
Treatment Description
This chemical detoxification of chlorinated
aromatic compounds detoxifies soils that have
been contaminated with dioxin, herbicides or
other chlorinated aromatic contaminants.
The contaminated soil is excavated and a
determination of the water content is made. If
the water content is too high, the soil is
dehydrated. Soil is placed in the reactor with
the reagent and heated to 100 to 150 degrees
Celsius. The reagent is a 1:1:1 mixture of
potassium hydroxide, polyethylene glycol, and
dimethyl sulfoxide. After reaction, the reactor is
drained and the soil is rinsed with clean water to
remove excess reagents. Treated soil might be
replaced in its original location depending upon
the effectiveness of the decontamination and
local environmental regulations.
Technology Performance
Demonstrations of this method achieved greater
than 99.9 percent decontamination. Several
advantages of this method were indicated:
• It is relatively inexpensive for contaminants
at low concentrations (in the ppm range);
• The reagents can be recycled;
• The products of the decontamination are
not toxic and are not biodegradable;
• Bioassay studies show that the reaction
products do not bioaccumulate or
bioconcentrate, they do not cause
mutagenicity, nor are they toxic to aquatic
organisms or mammals;
• The chlorine atoms are replaced by glycol
chains producing non-toxic aromatic
compounds and inorganic chloride
compounds; and
• The equipment components are
commercially available.
Despite the numerous advantages of this
technology, it also has limitations:
• For high contaminant concentrations in
the percent range, incineration could be
less expensive to use;
• Water might interfere with the reactions
between the reagents and the chlorinated
aromatic compounds; and
• Some chlorinated compounds, such as
hexachlorophene 24, are not degraded as
effectively as others.
Remediation Costs
The costs are in the range of $100 to $200 per
ton. The Naval Civil Engineering Laboratory
(NCEL) reports that the costs might be on the
order of $300 per cubic yard. The most
expensive item is the reagent.
General Site Information
Small-scale pilot testing (one to ten drums) has
been conducted on dioxin- contaminated soil by
the Air Force in the laboratory. Larger-scale
pilots are planned for the near future by the EPA
at Edison, New Jersey. A large-scale pilot (less
than ten drums) for PCB decontamination is
scheduled for testing in January 1988 in Guam.
The pilot will treat about 30 cubic yards to
determine cost effectiveness and develop design
criteria. Full-scale implementation is scheduled
for the end of 1988. The pilot reactor has a
capacity of two cubic yards. The capacity of the
full-scale reactor will be 20 to 30 cubic yards.
Federal Remediation Technologies Roundtable
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Contacts
Captain Edward Heyse
HQ AFESC/RDV
Tyndal! AFB, Florida 32403
904/283-2942
AutOVOn 523-2942
Deri Bin Chan
Environmental Protection Division
Naval Civil Engineering Laboratory
Port Hueneme, California 93043
805/982-4191
Atrtovon 360-4191
Additional information is available from:
Charles Rogers
EPA-HWERL
26 West St. Clair
Cincinnati, Ohio 45286
513/569-7757
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o
Chemical Treatment
Chemical Oxidation/Cyanide Destruction
Organics and Cyanide in Water, Soils, and Sludges
Technology Description
This treatment system uses chlorine dioxide,
generated on-site by a patented process, to
oxidize organically contaminated aqueous waste
streams, and simple and complex cyanide in
water or solid media. Chlorine dioxide is an
ideal oxidizing agent because it chemically alters
contaminants to salts and non-toxic organic
acids. This technology is applicable to aqueous
wastes, soils, or any teachable solid media
contaminated with organic compounds. This
technology also is applicable to ground water
contaminated .with pesticides or cyanide;
sludges containing cyanide, pentachlorophenol
(PCP) or other organics; and industrial
wastewater similar to refinery wastewater.
Chlorine dioxide gas is generated by reacting
sodium chlorite solution with chlorine gas, or by
reacting sodium chlorite solution with sodium
hypochlorite and hydrochloric acid. Both
processes produce at least 95 percent pure
chlorine dioxide.
In aqueous treatment systems the chlorine
dioxide gas is fed into the waste stream via a
venturi, which is the driving force for the
generation system. The amount of chlorine
dioxide required depends on the contaminant
concentrations in the waste stream and the
concentration of oxidizable compounds, such as
sulfides.
In soil treatment applications, the chlorine
dioxide may be applied in situ via conventional
injection wells or surface flushing. The
concentration of chlorine dioxide would depend
on the level of contaminants in the soil.
Chlorine dioxide treatment systems have been
applied to drinking water disinfection, food
processing sanitation, and as a biocide in
industrial process water. Since chlorine dioxide
reacts via direct oxidation rather than
substitution (as does chlorine), the process does
not form undesirable trihalomethanes.
Technology Performance
The SITE program has accepted two proposals
from Exxon Chemicals, Inc. and Rio Linda
Chemical Company to perform two separate
demonstrations: one of cyanide destruction and
the other of organics treatment. Site selection
for these demonstrations is currently underway.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Teri Shearer
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7949
FTS: 684-7949
Technology Developer Contact:
Tony Kurpakus
Exxon Chemical Company
4510 East Pacific Coast Highway
Mailbox 18
Long Beach, California 90805
213/597-1937
Federal Remediation Technologies Roundfable
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Chemical Treatment
Combined Chemical Binding / Precipitation
and Physical Separation of Radionuclides
Radionuclides and Heavy Metals in Water, Sludges or Soils
Technology Description
This chemical binding and physical separation
method involves rapid, turbulent, in-line mixing of
a proprietary fine powder (RHM1000) containing
complex oxides and other reactive binding
agents. RHM 1000 absorbs, adsorbs, and
chemisorbs most radionuclides and heavy
metals in water, sludges, or soils (pre-processed
into slurry), yielding coagulating, flocculating and
precipitating reactions. The amount of RHM
1000 required for processing ranges from 0.1
percent to less than 0.01 percent, depending on
the application. The pH, mixing dynamics, and
processing rates are carefully chosen to optimize
the binding of contaminants.
Water is separated from the solids using a
reliable, economical, two-stage process based
on two processes: (1) particle size and density
separation, using clarifier technology and
microfiitration of all particles and aggregates;
and (2) dewatering, using a filter press, to
produce a 70 to 85 percent dry filter cake with
the concentrated radionuclide(s), heavy metal(s),
and other solids. The filter cake is collected and
stabilized for disposal.
The process is designed for continuous through-
put for water (50-1500 gal/min) or batch mode
sludge and soil processing (300 tons per eight-
hour day). This technology can accommodate
trace levels, naturally occurring radioactive
materials (NORM), and low-level radioactive
wastes. The equipment is trailer-mounted for
use as a mobile field system. Larger capacity
systems could be skid-mounted.
This technology can be used for most
radionuclides and heavy metals in water,
sludges, or soils: (1) cleanup and remediation of
water, sludges, and soils contaminated with
radium, thorium, uranium and heavy metals from
uranium mining/milling operations; (2) cleanup of
water containing NORM and heavy metals from
oil and gas drilling; and (3) cleanup and
remediation of man-made radionuclides stored in
underground tanks, pits, ponds, or barrels. This
technology is not applicable to water containing
tritium.
Treatment Performance
EPA accepted this technology into the SITE
Demonstration Program in July 1990. The
Department of Energy (DOE) is working with EPA
to evaluate the TechTran's chemical binding and
physical separation process.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Annette Gatchett
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7697
FTS: 684-7697
Technology Developer Contact:
Tod S. Johnson
TechTran, Inc.
7705 Wright Road
Houston, Texas 77041
713/896-8205
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Federal Remediation Technologies Roundtable
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Thermal Treatment
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Thermal Treatment
Centrifugal Reactor
Metals and Organic Compounds in Soils and Sludges
Technology Description
The Centrifugal Reactor is a thermal treatment
technology that uses heat from a plasma torch
to create a molten bath that detoxifies soils and
sludges contaminated with metals and
hard-to-destroy organic compounds. Developed
by Retech, Inc., this technology vaporizes
organic contaminants at very high temperatures
to form innocuous products. The technology
melts solids and incorporates them into the
molten bath. When cooled, the result is a non-
leachable matrix that immobilizes the metals.
Contaminated soils enter the reactor through a
bulk feeder. The interior of the reactor (the
reactor well) rotates during waste processing.
Centrifugal force created by this rotation
prevents waste and molten material from flowing
out of the reactor through the bottom. It also
helps to transfer heat and electrical energy
evenly throughout the molten phase.
Periodically, a fraction of the molten slag is
tapped and falls into the collection chamber to
solidify.
Gases travel through the secondary combustion
chamber, where they remain at a high
temperature for an extended period of time. This
allows for further thermal destruction of any
organics remaining in the gas phase.
Downstream of the secondary combustion
chamber, the gases pass through a series of air
pollution control devices designed to remove
particulates and acid gases. In the event of a
process upset, a surge tank has been installed
to allow for the reprocessing of any off-gases
produced.
Technology Performance
A demonstration is planned for late 1991 at a
Department of Energy research facility in Butte,
Montana. During the demonstration, the reactor
will process approximately 4,000 pounds of
waste at a feed rate of 100 pounds per hour. All
feed and effluent streams will be sampled to
assess the performance of this technology. A
report on the demonstration project will be
available after its completion.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Laurel Staley
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7863
FTS: 684-7863
Technology Developer Contact:
R.C. Eschenbach
Retech, Inc.
P.O. Box 997
100 Henry Station Road
Ukiah, California 95482
707/462-6522
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Thermal Treatment
Circulating Bed Combustor
Halogenated and Non-Halogenated Hydrocarbons in
Soils, Slurries, and Sludges
Technology Description
The Ogden Circulating Bed Combustor (CBC)
uses high velocity air to entrain circulating solids
and create a highly turbulent combustion zone
for the efficient destruction of toxic
hydrocarbons. The CBC technology is
applicable to soils, slurries, and sludges
contaminated with halogenated and
nonhalogenated hydrocarbons. This technology
was recently applied at two site remediation
projects for treating soils contaminated with
polychlorinated biphenyls (RGBs) and fuel oil.
The CBC is one of seven incinerators permitted
to burn PCBs.
The Ogden CBC operates by feeding waste
material and limestone into the combustion
chamber along with the recirculating bed
material from the hot cyclone. The limestone
neutralizes acid gases. Hot gases produced
during combustion pass through a convective
gas cooler and baghouse before being released
to the atmosphere. The treated ash is
transported out of the system by an ash
conveyor for proper disposal.
The CBC technology operates at relatively low
temperatures (approximately 1600° F), thus
reducing operation costs. The high turbulence
produces a uniform temperature around the
combustion chamber, hot cyclone, and return
leg. It also promotes the complete mixing of the
waste material during combustion. The effective
mixing and relatively low combustion
temperature also reduce emissions of carbon
monoxide and nitrogen oxides.
can attain a destruction and removal efficiency
(ORE) of 99.99 percent for hazardous waste and
99.9999 percent for PCB waste.
Remediation Costs
Cost information is not available.
General Site Information
A test burn/treatability study of waste from the
McColl Superfund site was conducted in March
1989. EPA is currently reviewing results from
this pilot-scale demonstration.
Contacts
EPA Project Manager:
Joseph McSorley ;
U.S. EPA
Air & Energy Engineering
Research Laboratory
Alexander Drive
Research Triangle Park, North Carolina 27711
919/541-2920
FTS: 629-2920
Technology Developer Contact:
Brian Baxter
Ogden Environmental Services
10955 John J. Hopkins Drive
San Diego, California 92121
619/455-2613
Technology Performance
The commercial-size combustion chamber (36
inches in diameter) at the McColl Superfund site
can treat up to 100 tons of contaminated soil
daily, depending on the heating value of the feed
material. Ogden states that the CBC technology
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Federal Remediation Technologies Roundtable
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o
Thermal Treatment
Desorption and Vapor Extraction System
Volatile and Semivolatile Organics and Volatile Inorganics in
Soils, Sediments, and Sludges
Technology Description
The Desorption and Vapor Extraction System
(DAVES) uses a low-temperature, fluidized bed
to remove volatile and semivolatile organics,
including polychlorinated biphenyls (PCBs),
poly nuclear aromatic hydrocarbons (PAHs),
pentachiorophenol (PGP), volatile inorganics
(tetraethyl lead), and some pesticides from soil,
sludge, and sediment. In general, the process
treats waste containing less than 5 percent total
organic contaminants and 30 to 90 percent
solids/Nonvolatile inorganic contaminants (such
as metals) in the waste feed do not inhibit the
process, but are not treated.
Contaminated materials are fed into a co-current,
fluidized bed, where they are well mixed with hot
air (about 1,000 to 1,400° F) from a gas-fired
heater. Direct contact between the waste
material and the hot air forces water and
contaminants from the waste into the gas stream
at a relatively low fluidized-bed temperature
(about 320 ° F). The heated air, vaporized water
and organics, and entrained particles flow out of
the dryer to a gas treatment system.
The gas treatment system removes solid
particles, vaporized water, and organic vapors
from the air stream. A cyclone separator and
baghouse remove most of the particulates in the
gas stream from the dryer. Vapors from the
cyclone separator are cooled in a venturi
scrubber, counter-current washer, and chiller
section before they are treated in a vapor-phase
carbon adsorption system. The liquid residues
from the system are centrifuged, filtered, and
passed through two activated carbon beds
arranged in series.
By-products from the DAVES treatment include:
(1) approximately 96 to 98 percent of solid waste
feed as clean, dry solid; (2) a small quantity of
centrifuge sludge containing organics; (3) a
small quantity of spent adsorbent carbon; (4)
wastewater that may need further treatment; and
(5) small quantities of baghouse and cyclone
dust.
Technology Performance
EPA is currently selecting a demonstration site
for this process. The wastes preferred for the
demonstration are harbor or river sediments
containing at least 50 percent solids and
contaminated with PGBs and other volatile or
semivolatile organics. Soil with these
characteristics may also be acceptable. About
300 tons of waste are needed for a two-week
test. The demonstration may potentially be held
at the selected demonstration site or wastes may
be transported to a facility in Arizona that is
owned by the developer. Major test objectives
are to evaluate feed handling, decontamination
of solids, and treatment of gases generated by
the process.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Laurel Staley
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7863
FTS: 684-7863
Technology Developer Contact:
William C. Meenan
Recycling Sciences International, Inc.
30 South Wacker Drive
Suite 1420
Chicago, Illinois 60606
312/559-0122
Federal Remediation Technologies Roundtable
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' Qein Coine
Solidj
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Federal Remediation Technologies Roundtable
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T
Thermal Treatment
Flame Reactor
Volatile and Nonvolatile Metals in
Solids, Soils, Flue Dusts, Slags, and Sludges
Technology Description
This Flame Reactor process is a patented,
hydrocarbon-fueled, flash smelting system that
treats residues and wastes containing metals.
The Flame Reactor has been successfully tested
using electric arc furnace dust, lead blast
furnace slag, iron residues, zinc plant leach
residues and purification residues, and brass mill
dusts and fumes. Metal bearing wastes
previously treated contained zinc (up to 40
percent), lead (up to 10 percent), cadmium (up
to 3 percent), chromium (up to 3 percent), as
well as copper, cobalt, nickel and arsenic.
The reactor processes wastes with a very hot
(greater than 2000° C) reducing gas produced
from the combustion of solid or gaseous
hydrocarbon fuels in oxygen-enriched air. In a
compact, low-capital cost reactor, the feed
materials react rapidly, allowing a high waste
throughput. The end products are a non-
leachable slag (a glasslike solid when cooled)
and a recyclable, heavy metal-enriched oxide.
The volume reduction achieved (of waste to
slag) depends on the chemical and physical
properties of the waste.
This Flame Reactor technology applies
specifically to granular solids, soil, flue dusts,
slags, and sludges containing heavy metals.
The volatile metals are fumed and captured in a
product dust collection system, the nonvolatile
metals are encapsulated in the slag. At the
elevated temperature of the Flame Reactor
technology, organic compounds are destroyed.
In general, the process requires that wet
agglomerated wastes be dry enough (up to 15
percent total moisture) to be gravity-fed and fine
enough (less than 200 mesh) to react rapidly.
Larger particles (up to 20 mesh) can be
processed; however, a decrease in the efficiency
of metals recovery usually results.
Technology Performance
The Flame Reactor demonstration plant at
Monaca, Pennsylvania, has a capacity of 1.5 to
3.0 tons/hour. A SITE demonstration is
scheduled to be conducted at the Monaca
facility under a RCRA RD&D permit that will allow
the treatment of Superfund wastes containing
high concentrations of metals, but only negligible
concentrations of organics. The major objectives
of the SITE technology demonstration are to
evaluate: (1) the levels of contaminants in the
residual slag and their leaching potential; (2) the
efficiency and economics of processing; and (3)
the reuse potential for the recovered metal
oxides. Approximately 120 tons of contaminated
materials are needed for the test. The most
likely candidate wastes include mine tailings or
smelting waste such as slag, flue dust, and
wastewater treatment sludges. Pretreatment
may be required to produce a dryer feed and to
reduce the particle size.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Donald Oberacker and Marta K. Richards
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7510 and 513/569-7783
FTS: 684-7510 and FTS: 684-7783
Technology Developer Contact:
John F. Pusateri
Horsehead Resource Development Co., Inc.
300 Frankfort Road
Monaca, Pennsylvania 15061
412/773-2279
Federal Remediation Technologies Roundtable
37
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UI
C3
Thermal Treatment
Infrared Thermal Destruction
Organic Compounds, PCBs and Metals in Soil
Technology Description
This electric infrared incineration technology
(originally developed by Shirco Infrared Systems,
Inc. of Dallas, Texas) is a mobile thermal
processing system that is suitable for soils or
sediments contaminated with organic
compounds, polychlorinated biphenyls (PCBs),
and metals. Liquid organic wastes can be
treated after mixing with sand or soil.
This technology uses electrically-powered silicon
carbide rods to heat organic wastes to
combustion temperatures. Any remaining
combustibles are incinerated in an afterburner.
One configuration for this mobile system is
comprised of four components: an electric-
powered infrared primary chamber, a gas-fired
secondary combustion chamber, an emissions
control system, and a control center.
The infrared incineration technology process
operates by feeding waste into the primary
chamber on a wire-mesh conveyor belt and
exposing the waste to infrared radiant heat (up
to 1850° F) provided by the horizontal rows of
electrically-powered silicon carbide rods above
the belt. A blower delivers air to selected
locations along the belt and can be used to
control the oxidation rate of the waste feed. The
ash material that drops off the belt in the primary
chamber is quenched using scrubber water
effluent. The ash is then conveyed to the ash
hopper, where it is removed to a holding area
and analyzed for PCB content.
Volatile gases from the primary chamber flow
into the secondary chamber, which uses higher
temperatures, greaterresidencetime, turbulence,
and supplemental energy (if required) to destroy
these gases. Gases from the secondary
chamber are ducted through the emissions
control system. In the emissions control system,
the particulates are removed in a venturi
scrubber. Acid vapor is neutralized in a packed
tower scrubber. An induced draft blower draws
the cleaned gases from the scrubber into the
free-standing exhaust stack. An emergency stack
is installed prior to the venturi scrubber system
so that if the temperature control system and its
interlocks fail, the emissions control system will
not be melted by the hot gases. The scrubber
liquid effluent flows into a clarifier, where
scrubber sludge settles out for disposal, and
through an activated carbon filter for reuse or to
a publicly-owned treatment work (POTW) for
disposal.
Technology Performance
EPA has conducted two Superfund Innovative
Technology Evaluation (SITE) demonstrations for
the infrared thermal destruction technology. The
first demonstration was conducted at the Peak
Oil site in Tampa, Florida and the second
demonstration was performed at the Rose
Township-Demode Road site in Michigan. The
results of the two SITE demonstrations and eight
other case studies are summarized below:
• In both tests, at standard operating
conditions, PCBs were reduced to less
than one ppm in the ash, with a
destruction and removal efficiency
destruction and removal efficiency (DRE)
for air emissions greater than 99.99
percent (based on detection limits).
• In the pilot-scale demonstration, the
Resource Conservation and Recovery Act
(RCRA) standard for paniculate emission
(180 mg/dscf) was achieved. In the full-
scale demonstration, however, this
standard was not met in all runs due to
scrubber inefficiencies.
• Lead was not immobilized; however, most
lead remained in the ash and only in
significant amounts were transferred to
the scrubber water or emitted to the
atmosphere.
38
Federal Remediation Technologies Roundtable
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• The pilot testing demonstrated satisfactory
performance, with a high feed rate and
reduced power consumption, when fuel oil
was added to the waste feed and the
primary chamber temperature was
reduced.
• The process is capable of meeting both
RCRA and Toxic Substances Control Act
(TSCA) ORE requirements for air
emissions. Operations on waste feed
contaminated with PCBs have consistently
met the TSCA guidance level of two pprn
in ash;
• Improvements in the scrubber system
resulted in compliance with RCRA and
TSCA paniculate emission standards. In
some cases, restrictions in chloride levels
in the waste and/or feed rate may be
necessary to meet particulate emissions
standards; and
Data evaluated during the SITE Application
Analysis suggest that additional preprocessing
may be needed to meet suitable ranges for
various waste characteristics:
• Particle size, 5 microns to 2 inches;
• Moisture content, up to 50 percent (wt.);
• Density, 30-130 Ib/cf;
• Heating value, up to 10,000 Btu/lb;
• Chlorine content, up to 5 percent (wt.);
• Sulfur content, up to 5 percent (wt.);
• Phosphorus, 0-300 ppm;
• pH, 5-9; and
• Alkali metals, up to 1 percent (wt.).
Remediation Costs
Economic analysis and observation of the test
results suggest a cost range from $180/ton to
$240/ton of waste feed, excluding waste
excavation, feed preparation, profit, and ash
disposal costs. Overall costs may be as high as
$800/ton.
General Site Information
EPA conducted two evaluations of the infrared
system. EPA conducted a full-scale unit
evaluation from August 1 to 4, 1987, during a
removal action by Region IV at the Peak Oil site,
an abandoned oil refinery in Tampa, Florida.
During the cleanup, a nominal 100-ton per day
system treated nearly 7,000 cubic yards of waste
oil sludge containing PCBs and lead. A second
demonstration of the system, at pilot scale, took
place at the Rose Township-Demode Road site,
a National Priority List (NPL) site in Michigan,
from November 2 to 11, 1987. The pilot-scale
operation allowed the evaluation of performance
under varied operating conditions. Infrared
incineration was also used to remediate PCB-
contaminated materials at the Florida Steel
Corporation Superfund site and the LaSalle
Electric NPL site in Illinois.
Contacts
EPA Project Manager:
Howard O. Wall
U.S. EPA, RREL
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7691
FTS: 684-7691
Technology Developer Contact:
John Cioffi
Ecova Corporation
3820 159th Avenue, NE
Redmond, Washington 98052
206/883-1900
Technology Vendor Contacts:
George Hay
OH Materials Corporation
419/423-3526
Richard McAllister
Westinghouse Haztech, Inc.
404/593-3803
Federal Remediation Technologies Roundtable
39
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Thermal Treatment
Low-Temperature Thermal Stripping
Volatile Organic Compounds in Soil
Technology Description
Low-temperature thermal stripping of volatile
organic compounds (VOC) from soils removes
volatile components such as chlorinated solvents
and fuels. It can be applied to contaminated
soils associated with fire training pits, burn pits,
spills, and lagoons. Contaminants having boiling
points as high as 500 degrees Celsius have
been removed from soils.
During this process, a direct-fired boiler heats a
heat transfer fluid. The heated fluid then passes
through the shaft and flights of an auger and
through the trough jacket surrounding the auger.
Contaminated soil is introduced to the auger and
trough by a feed hopper that has a rotary valve
to ensure air-tight operation. Preheated air or an
inert gas is passed over the auger and sweeps
the volatilized contaminants to the treatment
system.
This method does, however, have a number of
limitations: this is a media transfer technique
rather than a destructive technique; treatment of
the gaseous effluent prior to discharge might be
required, depending upon local regulations;
bench-scale evaluation should be conducted
before pilot testing or implementation; the
equipment for the bench-scale test is available
and will fit in a standard laboratory hood; lower
explosive limits must be considered when
treating soils contaminated with flammable
solvents; an inert gas such as nitrogen might be
considered as an alternative to air to reduce the
risk of combustion or explosion; and since this is
a tow-temperature method, metal contaminants
will not be removed.
Remediation Costs
To treat a site containing 15,000 to 80,000 tons
of contaminated soil, the optimally sized process
costs would range from $74/ton to $160/ton,
respectively, without flue gas treatment. If
afterburner exhaust gases are treated prior to
discharge, the respective costs range from
$87/tonto$184/ton.
General Site Information
A large-scale pilot test (> 10 drums) was
conducted at Letterkenny Army Depot,
Chambersburg, PA. The contaminants were
primarily trichloroethylene, and xylene. More
than 99.9 percent of the total volatile organic
compounds were removed from the soil. Bench-
scale tests were also conducted on soils
contaminated with JP-4 and No.2 fuel oil, but the
results from these tests are not yet available.
Contacts
Greg Mohrman
USATHAMA
AMXTH-TE-D
Aberdeen Proving Ground, Maryland 21010-
5401
301/671-2054, Autovon 584-2054
Technology Performance
The results from this technology at Letterkenny
Army Depot were extremely positive in that more
than 99.9 percent of the total volatile organic
compounds were removed from the soil.
40
Federal Remediation Technologies Roundtable
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Thermal Treatment
Low Temperature Thermal Treatment (LT )
JP-4 and Other VOCs in Soil
Technology Description
Low Temperature Thermal Treatment (LT3) is a
demonstrated ex-situ process that provides
evaporation of VOCs from contaminated soil
without heating the soil matrix to combustion
temperatures. The primary element is the
thermal processor, an indirect heat exchanger
used to dry and heat contaminated soils, thus
stripping the moisture and VOCs from the soil.
A demonstration was designed to test the LT3
System by attempting to remove jet propulsion
fuel (JP-4) and chlorinated organic compounds,
such as triehloroethene (TCE), from
contaminated soil. The only modification to the
basic LT3 was the addition of a scrubber system
to control acid gas emissions.
The LT3 Process can be best described by
separating the system into three main
components: soil treatment, emissions control,
and water treatment. The soil treatment process
involves soil being fed into the thermal processor
(heat is provided by the self-contained hot-oil
system burner), where the VOCs in the soil are
vaporized and are drawn by an induced-draft
fan. Water is sprayed on the processed soil to
provide cooling and to minimize dust emissions.
Processed soil is stored in an enclosed dump
truck for transportation to a soil staging area.
The emission control system involves several
steps. A fabric filter is used to remove
particulates from the vapor drawn by the
induced draft fan. Particulates are removed from
the filter and added to the contaminated soils for
reprocessing. An air-cooled condenser is used
to remove condensable water vapor and
organics from the exhaust gas. Condensed
liquid is pumped into the water treatment
system. The process gases from the condenser
pass through an afterburner to destroy organics
that remain in the exhaust. A continuous
emissions monitoring system monitors
afterburner exhaust for oxygen, carbon
monoxide, carbon dioxide, and total
hydrocarbons. Gases entering the scrubber are
cooled to saturation temperature, and acidic
gases are neutralized.
Liquid exiting the condenser is collected and
pumped to a gravity operated oil/water
separator. Light organics are removed by a
skimmer; water is syphoned off. Heavy liquids,
such as TCE, are syphoned with the water and
later filtered in the carbon system. The organics
are stored in 55 gallon drums for off-site
disposal. The water is directed through two
carbon adsorption units for removal of soluble
organics. After leaving this system, the water is
stored in a fresh water tank, to be used later in
dust control. No water is discharged from the
LT3 system.
Technology Performance
Remedial investigation reports from the Tinker Air
Force Base site in Oklahoma City, Oklahoma
indicate that the contamination was extensive
and varied in composition. The feed soil
contamination levels and cleanup goals identified
for some contaminants were: average TCE
concentration - 743,270 ug/kg, cleanup goal - 70
ug/L; average total xylenes - 13,044 ug/kg,
cleanup goal - 150 ug/L; and average toluene
concentrations - 39,341 ug/kg, cleanup goal -
330 ug/L.
The demonstration showed conclusively that the
LT3 technology was effective in reducing the
concentration of not only JP-4 but also all
compounds originally specified in the Test Plan.
All goal cleanup levels could be met by heating
the processed soil above 215° F. This was a
considerably lower temperature than anticipated.
As a result, all goal cleanup levels were met
while processing soil at rates 25 percent in
excess of the design capacity. The treatment
capacity was 18,000 - 20,000 Ibs per hour.
Although an evaluation of the effectiveness of
stripping agents in the removal of the
compounds was an original objective, this was
Federal Remediation Technologies Roundtable
41
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not accomplished. The demonstration was
discontinued when polychlorinated biphenyls
(PCBs) were discovered in the feed and
processed soils because the system was not
designed to process PCBs. Although definitive
stack testing was not conducted to verify system
performance, all Federal, State, and local
emissions standards, as specified in the permit,
were believed to have been met.
Remediation Costs
The unit cost for processing and
decontaminating soil with similar contaminants is
$86.00 per ton of soil at an average processing
rate of 8 tons per hour. Total estimated costs,
including mobilization and demobilization, to
process 5,000 tons would be $116.00 per ton.
Fixed costs for mobilization, start up, and
demobilization are approximately $150,000.00.
General Site Information
This full-scale demonstration was conducted at
Tinker Air Force Base in Oklahoma City,
Oklahoma. The demonstration was conducted
between July 17 and August 18,1989. The feed
soils were excavated from the Landfill 3 sludge
dump area, which received waste oils and liquids
from industrial operations at Tinker Air Force
Base between 1961 and 1968.
Four types of materials were encountered in the
Landfill 3 sludge area: overburden, or fill;
crumbled asphalt mixed with clay; a sludge
marbled with native clay; and a dry red clay. At
no time was water or a saturated layer
encountered at depths of less than 14 feet. The
sludge/clay layer (with a strong solvent odor)
was found to be the source of contamination.
This layer was found at a depth of 2 to 15 feet
below surface, and was 1 to 12 feet thick. A
total of 3,000 cubic yards of material was
excavated during the operation.
Contacts
EPA Project Manager:
Roger K. Nielson ;
U.S. EPA Region VI
USATHAMA - Aberdeen Proving Grounds:
Craig A. Myler - CETHA-TS-D
Aberdeen Proving Ground, Maryland
21010-5401
301/671-2054
Technology Developer Contact:
Peter J. Marks - Program Manager
Roy F. Weston, Inc.
One Weston Way
West Chester, Pennsylvania 19380
42
Federal Remediation Technologies Roundtable
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Thermal Treatment
Pyretron® Oxygen Burner
Hazardous Organics in Solids, Sludges, and Liquids
Technology Description
The Pyretron® technology uses advanced fuel
injection and mixing concepts to burn solid
wastes contaminated with hazardous organics.
Specifically, the Pyretron® oxygen-air-fuel burner
incinerates pure oxygen combined with air and
natural gas, destroying solid hazardous waste in
the process. The burner operation is .computer-
controlled to automatically adjust the amount of
oxygen to sudden changes in the heating value
of the waste.
The burner can be fitted onto any conventional
combustion unit for burning liquids, solids and
sludges. Solids and sludges can be
co-incinerated when the burner is used in
conjunction with a rotary kiln or similar
equipment. In general, the technology is
applicable to any waste that can be incinerated.
However, the technology is not suitable for
processing aqueous wastes, RCRA heavy metal
wastes, or inorganic wastes.
Technology Performance
This technology was tested in a SITE
demonstration project at EPA's Combustion
Research Facility using a mixture of 40 percent
contaminated soil from a Superfund site and 60
percent decanter tank tar sludge from coking
operations. Six polynuclear aromatic
hydrocarbon compounds were selected as the
principal organic hazardous constituents (POHC)
for the test program: naphthalene,
acetaphthylene, fluorene, phenanthrene,
anthracene, and fluoranthene.
The Pyretron® technology achieved greater than
99.99 percent destruction and removal
efficiencies (ORE) of all POHCs measured in all
test runs performed. Several promising results
were observed in the demonstration:
* The Pyretron® technology, with oxygen
enhancement, achieved double the waste
throughput possible with conventional
incineration;
• All particulate emission levels in the
scrubber system discharge were
significantly below the hazardous waste
incinerator performance standard of 180
mg/dscm at seven percent oxygen;
• Solid residues were contaminant-free;
• There were no significant differences in
transient carbon monoxide level emissions
between air-only incineration and
Pyretron® oxygen enhanced operation;
and
• Costs savings were able to be achieved in
many situations.
Field evaluations were conducted under the SITE
Demonstration Program, yielding several
conclusions:
• The Pyretron® burner system is a viable
technology for treating Superfund wastes;
• The system is capable of doubling the
capacity of a conventional rotary kiln
incinerator. This increase is more
significant for wastes with low heating
values;
• In situations where particulate carryover
causes operational problems, the
Pyretron® system may increase reliability;
and i
• The technology can be an economical
addition to an incinerator when operating
and fuel costs are high, and-oxygen costs
are relatively low.
EPA has published both the Technology
Evaluation Report and Application Analysis
Report for this technology.
44
Federal Remediation Technologies Roundtable
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Remediation Costs
General Site Information
The capital costs for the Pyretron® system used
in the SITE demonstration was $150,000. In
addition, $50,000 was spent in design and
development work on the system.
Since this demonstration was done at a research
facility and not under actual field conditions, the
incremental effect that using the Pyretron® has
on the cost of incinerating a ton of hazardous
waste cannot be directly determined. It is likely
that the major factor in determining the cost
effectiveness of the Pyretron® will remain the
oxygen and fuel. These costs vary widely
depending upon location and scale of operation.
The two major utility costs for the demonstration
were for auxiliary fuel (propane) and for oxygen.
Oxygen was supplied to the program by Big
Three Industries at no cost. The demonstration
tests consumed about 36,800 sm3 (1,300 MSCF)
of oxygen. At typical oxygen costs, between
$3,250 and $4,875 worth of oxygen was
consumed over the test program.
A total of 1,760 GJ (1,670 million Btu) of propane
was consumed over the demonstration test
program. At typical propane costs between
$5,000 and $10,000 worth of propane was
consumed during the oxygen enhanced test
program. About 40 percent of the propane was
fired during the Pyretron® system tests. The
remaining 60 percent was consumed during the
conventional incineration tests.
EPA conducted the demonstration project at its
Combustion Research Facility in Jefferson,
Arkansas, using a mixture of 40 percent
contaminated soil from the Stringfellow Acid Pit
Superfund site in California and 60 percent
decanter tank tar sludge from coking operations
(RCRA listed waste K087). The demonstration
began in November 1987 and was completed in
January 1988.
Contacts
EPA Project Manager:
Laurel Staley
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7863
FTS: 684-7863
Technology Developer Contact:
Gregory Gitman
American Combustion Technologies, Inc.
2985 Gateway Drive, Suite 100
Norcross, Georgia 30071
404/662-8156
Federal Remediation Technologies Roundtable
45
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Thermal Treatment
Radio Frequency (RF) Thermal Soil Decontamination
Solvents and Volatile and Semi-volatile Petroleum in Soils
Technology Description
The radio frequency (RF) thermal soil
decontamination process removes volatile
hazardous waste materials through in situ radio
frequency heating of the soil and volatilization of
the hazardous substances. This technology can
be applied to fire training pits, spills, and sludge
pits containing solvents and volatile and semi-
volatile petroleum.
Radio frequency heating is performed by the
application of electromagnetic energy in the
radio frequency band. The energy is delivered
by electrodes placed in holes drilled through the
soil. The mechanism of heat generation is
similar to that of a microwave oven and does not
rely on the thermal properties of the soil matrix.
The power source for the process is a modified
radio transmitter. The exact frequency of
operation is selected after evaluation of the
dielectric properties of the soil matrix and the
size of the area requiring treatment. The gases
and vapors formed in the soil matrix can be
recovered at the surface or through the
electrodes used for the heating process.
Condensation and collection of the concentrated
vapor stream is used to capture the contaminant
above ground. The system is made up of four
components: (1) RF energy deposition electrode
array; (2) RF power generation, transmission,
monitoring, and control system; (3) vapor barrier
and containment system; and (4) gas and liquid
condensate handling and treatment system.
This technology has a number of advantages:
• Demonstrations have shown higher than
90 percent reduction of jet fuel
components from soils;
• Contaminants are recovered in a relatively
concentrated form without dilution from
large volumes of air or combustion gases;
• This is an in situ method;
• All equipment is portable; and
• The soil does not have to be excavated.
Limitations of this technology include:
• High moisture or presence of ground
water in the treatment zone will result in
excessive power requirements to heat the
soil; and
• The method cannot be used if large
buried metal objects are in the treatment
zone.
Technology Performance
The full-scale field demonstration at Volk Field Air
National Guard Base, Camp Douglas, Wl
produced positive results:
• 94 to 99 percent decontamination of a 500
cubic feet block of soil was achieved
during a 12-day period. 97 percent of
semivolatile hydrocarbons and 99 percent
of volatile aromatics and aliphatics were
removed; ;
• Contaminant removal at the 2 meter
depth, the fringe of the heated zone,
exceeded 95 percent;
• The 70-76 percent contaminant reduction
in the immediate area outside the heated
zone indicates that there was no net
migration of contaminant from the heated
area to the surrounding soil; and
• Results show that substantial removal of
high boiling contaminants can be
achieved at temperatures significantly
lower than their boiling point. This occurs
due to the long residence time provided at
lower temperatures and steam distillation
provided by the native moisture.
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Federal Remediation Technologies Roundtable
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Remediation Costs
It is estimated that the treatment cost will vary
between $28 to $60 per ton of soil. Based upon
the bench-scale tests, it is estimated that the
treatment of a 3-acre site to a depth of 8 feet
containing 12 percent moisture raised to a
temperature of 170 degrees Celsius would cost
$42 per ton. The treatment of such a site would
require about one year. The initial capital
equipment investment for full-scale projects is
estimated to be about $1.5 million. Power
requirements are approximately 500 kwhr per
cubic yard to reach a temperature of 150
degrees Celsius.
Contacts
Capt. Ed Marchand
HQ AFESC/RDVW
Tyndall AFB, Florida 32403-6001
DSN 523-6023
Lt. Col. Brady
HQ/AFEC/YE
Tyndall AFB, Florida 32403
904/283-6259, Autovon 423-6295
General Site Information
A bench-scale pilot test (volume < 20 drums)
has been conducted at ITT Research Institute
facilities. A full-scale demonstration was
completed at Volk Field (ANGB), Wl during
October 1989. Full-scale implementation began
during the Fall of 1990 at Kelly AFB, San
Antonio, Texas.
RF Power
Source
Vapor Barrier
Exciter Electrodes
Ground Electrodes 8
— Gas and Vapor
Treatment System
Federal Remediation Technologies Roundtable
47
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s
Thermal Treatment
Waste-to-Fuel Recycling
Petroleum Hydrocarbons in Sludges
Technology Description
This thermal treatment process is a mobile, low-
temperature, recycling process that produces
solid fossil fuel from otherwise hazardous, oily
petroleum sludges. A thick, sticky tar or waste
is converted into a light, organic liquid and a
solid cake, that can be more easily handled. A
screw flight dryer (auger) dries the petroleum
sludges, resulting in a fossil fuel product. Other
by-products include a light hydrocarbon liquid
and water. These by-products condense from
vapors emitted during the heating stages of the
process. Hydrocarbons are recycled and the
water is treated before release.
This process is applicable to petroleum sludges.
The sludge must not have a low pH and must be
dewatered to a maximum of 50 to 60 percent
moisture. The sludge must be screened to
prevent large debris from entering the dryer.
Technology Performance
Pilot scale tests have been conducted on
hazardous petroleum refinery sludges. This
technology was accepted into the SITE
Demonstration Program in June 1990.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Paul dePercin '.
U.S. EPA [
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7797
FTS: 684-7797
Technology Developer Contact:
George Lane
Thermal Waste Management
237 Royal Street
New Orleans, Louisiana 70130 '.
504/525-9722
48
Federal Remediation Technologies Roundtable
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\
\
o
Thermal Treatment
X*TRAX™ Low-Temperature Thermal Desorption
Organics in Soil
Technology Description
The X*TRAX™ technology is a low-temperature
(200 to 900° F) thermal separation process
designed to remove organic contaminants from
soils, sludges, and other solid media. It is not
an incinerator or a pyrolysis system. Chemical
oxidation and reactions are not encouraged, and
no combustion byproducts are formed. The
organic contaminants are removed as a
condensed high BTU liquid, which must then be
either destroyed in a permitted incinerator or
used as a supplemental fuel. Because of lower
operating temperatures and gas flow rates, this
process is less expensive than incineration.
An externally-fired rotary dryer is used to
volatilize the water and organic' contaminants
into an inert carrier gas stream. The processed
solids are then cooled with condensed water.
The moisture content is adjusted to eliminate
dusting and produce a solid that is ready to be
placed and compacted in its original location.
The feed rate, the dryer temperature, and the
residence time of materials in the dryer can be
adjusted to control the degree of contaminant
removal.
The organic contaminants and water vapor
driven from the solid are transported out of the
dryer by an inert nitrogen carrier gas. The
carrier gas flows through a duct to the gas
treatment system, where organic vapors, water
vapors, and dust particles are removed and
recovered from the gas. The gas first passes
through a high-energy scrubber. Dust particles
and 10 to 30 percent of the organic
contaminants are removed by the scrubber. The
gas then passes through two heat exchangers in
series, where it is cooled to less than 40°F.
Most of the remaining organic and water vapors
are condensed as liquids in the heat
exchangers.
The majority of the carrier gas passing through
the gas treatment system is reheated and
recycled to the dryer. Approximately 5 to 10
percent of the gas is cleaned by passing it
through a filter and two carbon adsorbers,
before it is discharged to the atmosphere. The
volume of gas released from this process vent is
approximately 100 to 200 times less than an
equivalent capacity incinerator. This discharge
helps maintain a small negative pressure within
the system and prevents potentially
contaminated gases from leaking. The
discharge also allows makeup nitrogen to be
added to the system, preventing oxygen
concentrations from exceeding combustibility
limits.
Technology Performance
Chem-Waste Management currently has three
X*TRAX systems available: laboratory, pilot, and
full-scale. There are two laboratory-scale
systems being used for treatability studies. One
system is operated by Chem Nuclear systems,
Inc. in Barnwell, SC for mixed
(RCRA/Radioactive) wastes; and the other by
CWM RD&D at its facility in Geneva, IL, for RCRA
and Toxic Substances and Control Act (TSCA)
wastes. More than 30 tests have been
completed since January 1988. Results from
these laboratory-scale tests included 97.9
percent removal efficiency for soil contaminated
with 805 ppm polychlorinated biphenyls (PCBs).
The pilot-scale system is in operation at the
CWM Kettleman Hills facility in California. During
1989-90, ten different PCB- contaminated soils
were processed under a TSCA RD&D permit
which expired in January 1990. For soils
containing 120 to 6,000 ppm PCBs, the removal
efficiency ranged from 97.2 to 99.5%. Nine of
the ten soils were reduced to less than 25 ppm.
The first Model 200 full-scale X*TRAX system
was completed in early 1990. The system will be
used to remediate 35,000 tons of PCB-
contaminated soil. EPA plans to conduct a SITE
demonstration during this remediation.
Federal Remediation Technologies Roundtable
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This technology was developed primarily for on-
site remediation of organic contaminated soils.
The process can remove and collect volatiles,
semivolatiles, and PCBs, and has been
demonstrated on a variety of soils ranging from
sand to very cohesive clays. Filter cakes and
pond sludges have also been successfully
processed. In most .cases, volatile organics are
reduced to below 1 ppm and frequently to below
the laboratory detection level. Semivolatile
organics are typically reduced to less than 10
ppm and frequently below 1 ppm. Soils
containing 120 to 6,000 ppm PCBs have been
reduced to 2 to 25 ppm.
This process is not applicable to heavy metals,
with the exception 'of mercury. However,
stabilization agents can be added to the feed or
treated solids before cooling for metals
treatment. Tars and heavy pitches create
material handling problems.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Paul dePercin
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive ,'
Cincinnati, Ohio 45268
513/569-7797
FTS: 684-7797
Technology Developer Contact:
Carl Swanstrom
Chemical Waste Management, Inc.
Geneva Research Center
1950 S. Batavia
Geneva, Illinois 60134
708/513-4578
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Vapor Extraction
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Vapor Extraction
Ground-Water Vapor Recovery System
Volatile Organic Compounds in Ground Water
Technology Description
In this treatment, injection and extraction wells
are placed outside and inside of an area of
contamination. Positive pressure, from either
water or air, is placed on the injections wells.
Water is pumped from the extraction wells to a
thermal aeration system to drive off the
contaminants. Resulting vapors go to an internal
combustion engine. If enough free product is
available in the ground water during the cleanup
process, waste hydrocarbons could be used to
power the engine without the need for additional
fuel.
Technology Performance
Full-scale implementation of this system is
scheduled in 1991 at the Seal Beach Navy
Weapons Station. This method is applicable for
volatile fuels or other volatile organic
compounds. This treatment requires that the
contaminant be combustible. Air permits are
required in some areas.
Remediation Costs
The capitol cost for purchasing and installing the
engine and wells is between $70,000 and
$100,000.
Contacts
Vern Novstrup
Naval Energy and Environmental Support
Activity, Code 112E
Port Hueneme, California 93043
805/982-2636
Rebecca Coleman-Roush
Remediation Service, International
P.O. Box 1601
Oxnard, California 93032
805/644-5892
Federal Remediation Technologies Roundtable
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Vapor Extraction
In Situ Air Stripping with Horizontal Wells
TCE and PCE in Soil and Ground Water
Technology Description
In situ air stripping using horizontal wells is
designed to concurrently remediate unsaturate-
zone soils and ground water containing volatile
organic compounds (VOCs). The in situ air
stripping concept utilizes two parallel horizontal
wells: one below the water table and one in the
unsaturated (vadose) zone. A diagram of the
technology has been provided. The deeper well
is used as a delivery system for the air injection.
VOCs are stripped from the ground water into
the injected vapor phase and are removed from
the subsurface by drawing a vacuum on the
shallower well in the vadose zone. The
technology is based on Henry's Law, and the
affinity of VOCs for the vapor phase. The
technology is probably most effective in soils
with high permeability and likely works best in
sandier units with no significant aquitards
between the injection and extraction wells.
Horizontal wells are utilized because they
provide more surface area for injection of
reactants and extraction of contaminants and
they have great utility for subsurface access
under existing facilities.
First, a vacuum was drawn on the shallow well
for a period of two weeks. Concentration and
temperature of the extracted vapors were
measured at least three times a day. Air
injection was then added at three different rates
and at two different temperatures. Each of the
operating regimes was operated for a minimum
of two weeks. Helium tracer tests were also
conducted to learn more about vapor flow paths
and the heterogeneity of the system between the
two wells. To assist with analysis and monitoring
of the demonstration, tubes of varying lengths
were installed in both horizontal wells to monitor
pressure and concentrations along their entire
length.
Technology Performance
Almost 16,000 pounds of solvents were removed
during the test at the U.S. Department of
Energy's (DOE) Savannah River Site (SRS).
Extraction rates during the vapor extraction
phase averaged 110 pounds of VOCs per day.
The extraction flow rate was constant at
approximately 580 scfm during the entire length
of the test. During the air injection periods with
medium (170 scfm) and high (270 ,scfm). rates,
approximately 130 pounds of VOCs were
removed daily.
Concentrations of chlorinated solvents removed
during vapor extraction only decreased rapidly
during the first two days of operation. Initial
concentrations were as high as 5,000 ppm but
stabilized at 200 to 300 ppm. Concentrations of
VOCs in the ground water were significantly
reduced in several of the monitoring wells. For
example, ground water from two monitoring wells
showed changes from 1600 and 1800 ug/L TCE
at the beginning of the test to 10 to 30 ug/L at
the end of the 20-weeks. However, ground
water in several of the wells showed no
significant change and ground water in three
wells actually had trichlorethylene (TCE)
concentrations increase. One possible
explanation for this was that more contaminated
water at depth (below the monitoring point) was
being forced upward due to air injection.
The activity of indigenous microorganisms was
found to increase at least an order of magnitude
during the air injection periods. This activity then
decreased when the air injection was terminated.
It is possible that simple injection of air
stimulated microorganisms that have the
potential to degrade TCE. Injection of heated air
appeared to have no effect on the amount of
contaminant extracted from the shallow well.
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Remediation Costs
The cost of the remediation project, not including
site characterization was approximately
$300,000, or $20/pound of contaminant removal.
Site preparation costs, including well installation
were $300,000 to $450,000. Equipment for this
demonstration test was rented, however
purchase of the vacuum blower and compressor
would be in the range of $200,000.
General Site Information
This 20-week field demonstration project was
conducted at the U.S. Department of Energy's
(DOE) Savannah River Site (SRS) in Aiken,
South Carolina, between July and December,
1990. Trichloroethylene (TCE) and
tetrachloroethylene (PCE) were used at SRS as
metal degreasing solvents for a number of years.
The in situ test was conducted at the SRS
Integrated Demonstration Site in the M-Area,
along an abandoned process sewer line that
carried wastes to a seepage basin which was
operated between 1958 and 1985. A ground-
water plume containing elevated levels of these
compounds exists over an area greater than one
square mile. The sewer line acted as a source
of VOCs as it is known to have leaked at
numerous locations along its length. Because
the source of contamination was linear at this
particular location within the overall plurne,
horizontal wells were selected as the
injection/extraction system.
The Savannah River Site is located on the upper
Atlantic Coastal Plain. The site is underlain by a
thick wedge of unconsolidated Tertiary and
Cretaceous sediments that overlay the
basement, which consists of preCambrian and
Paleozoic metamorphic rocks and consolidated
Triassic sediments. Ground-water flow at the
site is controlled by hydrologic boundaries: flow
at and immediately below the water table is to
local tributaries; and flow in the lower aquifer is
to the Savannah River or one of its major
tributaries. The water table is located at
approximately 135 feet. Ground water in the
vicinity of the process sewer line contains
elevated concentrations of TCE and PCE to
depths of greater than 180 feet.
Contacts
Facility Contact:
Mike O'Rear
DOE Savannah River
Aiken, South Carolina
803/725-5541
Contractor Contacts:
Dawn S. Kaback
Westinghouse Savannah River Company
Aiken, South Carolina
803/725-5190
Brian B. Looney
Westinghouse Savannah River Company
Aiken, South Carolina
803/725-5181
Federal Remediation Technologies Roundtable
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Injection Point for Air
Extraction of Air Containing Volatile Compounds
Ground Surface
""^ Slotted Casing
Contaminated Zone
f13120-1
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Vapor Extraction
In Situ Soil Venting
Fuels and Trichloroethylene in Unsaturated Soils
Technology Description
The in situ soil venting process removes volatile
contaminants such as fuels and trichloroethylene
from unsaturated soils. This technology can be
applied to fire training pits, spills and the
unsaturated zone beneath leach pits. The
method is most applicable for contamination at
depths greater than 40 feet .in fairly permeable
soils.
Venting wells are placed in the unsaturated zone
and connected to a manifold and blower. A
vacuum is applied to the manifold, and gases
are extracted from the soil and fed to the
treatment system. The air flow sweeps out the
soil gas, disrupting the equilibrium existing
between the contaminant adsorbed on the soil
and its vapor phase. This results in further
volatilization of the contaminant on the soil and
subsequent removal in the air stream.
Depending upon the individual site and the
depth of the contaminated zone, it might be
necessary to seal the surface to the throughput
of air.
This technology has a number of advantages.
Specifically, it is inexpensive, especially if the
emissions require no treatment. The equipment
is easily emplaced. It is less expensive than
excavation at depths greater than forty feet, and
the costs are similar for depths between 10 and
40 feet. Operation is simple, excavation of
contaminated soil is not required, and the site is
not destroyed.
Despite the advantages of this technology,
limitations do exist. This process is a transfer-of-
media method - the waste is not destroyed. At
depths of less than 10 feet, excavation could be
less expensive, depending upon the type of
waste treatment required. The contamination
must be located in the unsaturated zone above
the nearest aquifer. Prior bench-scale testing is
important in determining the effectiveness of the
method to a specific site. To date, few field data
exist on the level of cleanup. If the
contamination includes toxic volatile organic
carbons, then treatment of the vented gases
may be required. The level of treatment is
based upon local requirements.
Technology Performance
Analysis of the technology demonstration at Hill
Air Force Base (AFB) have shown the following
results:
• Soil gas venting may provide oxygen for
biodegradation;
• Based on data from extracted gases, 80
percent of a 100,000-liter fuel spill was
removed in 9 months of operation;
• Soil analysis following a full-scale in situ
field test indicated an average fuel
residual of less than 100 ppm in the soils;
• At initial air flow rates of 250 cubic feet per
minute, the full-scale system was
removing 50 gallons per day of JP-4 from
the soil. The venting rates were then
increased to over 1,000 cubic feet per
minute. After ten months of venting, over
100,000 pounds of JP-4 had been
removed. Hill AFB continues to operate
the system at a reduced flow rate to
enhance the in situ biodegradation of
remaining hydrocarbons; and
• Approximately 20-25 percent of the
reduction in fuel hydrocarbons was
caused by biodegradation.
Remediation Costs
The costs range from $15 per ton of
contaminated soil, excluding emission treatment,
up to approximately $85 per ton using activated
carbon emission treatment. Estimated costs of
this technology for sandy soils is $10 a cubic
Federal Remediation Technologies Roundtable
55
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yard. Catalytic incineration of VOCs can double
this cost. However, at Hill AFB, catalytic
incineration only cost $10 per cubic yard.
General Site Information
Operation of a full-scale in situ soil-venting
system at a 27,000-gallon JP-4 spill at Hill AFB
began in December 1988. A full-scale in situ
field test was completed in October 1989 at Hill
AFB, Utah.
Contacts
Hill Air Force Base Demonstration:
Capt. Edward G. Marchand
HQ AFESC/RDV
Tyndall AFB, Florida 32403-5001
504/283-4628
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Federal Remediation Technologies Roundtable
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Vapor Extraction
In Siltu Soil Venting
Volatile Contaminants in Unsaturated Soil
Technology Description
This in situ soil venting process removes volatile
contaminants from unsaturated soils. This
technology can be applied to fire training pits,
spills, and the unsaturated zone beneath leach
pits. The method is most applicable for
contamination at depths greater than 40 feet in
fairly permeable soils.
Venting wells are placed in the unsaturated zone
and connected to a manifold and blower. A
vacuum is applied to the manifold, and gases
are extracted from the soil and fed to the
treatment system. Depending upon the
individual site and depth of the contaminated
zone, it might be necessary to seal the surface
to prevent channeling. Air injection wells can be
used to increase the throughput of air.
General Site Information
This method has been implemented by the Army
at the Twin Cities Army Ammunition Plant
(TCAAP) in Minnesota.
Contacts
Greg Mohrman
USATHAMA
AMXTH-TE-D
Aberdeen Proving Ground, Maryland 21010
301/671-2054
Technology Performance
Pilot-scale testing at the Twin Cities Army
Ammunition Plant (TCAAP) has removed 70 tons
of contaminants from the soil in one area, but
the absolute extent of cleanup has not yet been
determined. This method is considered most
applicable for contamination at depths greater
than 40 feet in fairly permeable soils.
Remediation Costs
The costs for in situ soil venting can be as low
as $15 per ton of contaminated soil, excluding
emission treatment. If carbon adsorption
treatment is used, the costs could be around
$85 per ton. Based upon the pilot study at
TCAAP, the cost to treat a site contaminated to
a depth of 20 feet was between $15 and $20 per
cubic yard, including carbon adsorption
treatment of the contaminated air and soil
sampling.
Federal Remediation Technologies Roundtable
57
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UI
O
Vapor Extraction
In Situ Steam/Air Stripping Process
VOCs in Soil
Technology Description
The two main components of the Toxic
Treatments (USA) Inc. in situ steam/air stripping
process are the process tower and process train.
The process tower contains two counter-rotating
hollow-stem drills, each with a modified cutting
bit five feet in diameter, capable of operating to
a 27-foot depth. Each drill contains two
concentric pipes. The inner pipe is used to
convey steam to the rotating cutting blades. The
steam is supplied by an oil-fired boiler at 450°F
and 450 psig. The outer pipe conveys air at
approximately 300°F and 250 psig to the rotating
blades.
Steam is piped to the top of the drills and
injected through the cutting blades. The steam
heats the ground being remediated, increasing
the vapor pressure of the volatile contaminants
and thereby increasing the rate at which they
can be stripped. Both the air and steam serve
as carriers to convey these contaminants to the
surface. A metal box, called a shroud, seals the
process area above the rotating cutter blades
from the outside environment, collects the
volatile contaminants, and ducts them to the
process train.
In the process train, the volatile contaminants
and the water vapor are removed from the
off-gas stream by condensation. The condensed
water is separated from the contaminants by
distillation, then filtered through activated carbon
beds and subsequently used as make-up water
for a wet cooling tower. Steam is also used to
regenerate the activated carbon beds and as the
heat source for distilling the volatile
contaminants from the condensed liquid stream.
The recovered concentrated organic liquid can
be recycled or used as a fuel in an incinerator.
This technology is applicable to organic
contaminants, such as hydrocarbons and
solvents with sufficient vapor pressure in the soil.
The technology is not limited by soil particle size,
initial porosity, chemical concentration, or
viscosity.
Technology Performance
The SITE demonstration of the technology at the
Annex Terminal in San Pedro, California
exhibited promising results:
• Greater than 85 percent of the volatile
organic compounds (VOCs) in the soil
were removed;
• As much as 55 percent of semivolatile
organic compounds (SVOCs) in the soil
were removed;
• Fugitive air emissions from the process
were very low; and
• No downward migration of contaminants
occurred due to the soil treatment.
Remediation Costs
Cost information is not available.
General Site Information
A SITE demonstration was performed the week
of September 18, 1989 at the Annex Terminal,
San Pedro, California. Twelve soil blocks were
treated for VOCs and SVOCs. EPA collected
various liquid samples and closely monitored
and recorded operating procedures. During the
demonstration EPA collected and analyzed post-
treatment soil samples of EPA 8240 and 8270
chemicals. In January 1990, six blocks, which
had been previously treated in the saturated
zone, were analyzed for EPA 8240 and 8270
chemicals. Currently, the Technology Evaluation
Report has obtained EPA clearance for
publication. The Application Analysis Report is
being prepared.
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Contacts
EPA Project Manager:
Paul dePercin
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7797
FTS: 684-7797
Technology Developer Contact:
Phillip N. LaMori
Toxic Treatments (USA) Inc.
151 Union Street
Suite 155
San Francisco, California 94111
415/391-2113
or
P.O. Box 789
San Pedro, California 90733
213/514-0881
Federal Remediation Technologies Roundtable
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\
tu
a
Vapor Extraction
Integrated Vapor Extraction and Steam Vacuum Stripping
VOCs in Ground Water and Soil
Technology Description
The integrated AquaDetox/SVE system
simultaneously treats ground water and soil
contaminated with volatile organic compounds
(VOCs). The integrated system consists of two
basic processes: an AquaDetox moderate
vacuum stripping tower that uses low-pressure
steam to treat contaminated ground water, and
a soil gas vapor extraction/reinjection (SVE)
process to treat contaminated soil. The two
processes form a closed-loop system that
provides simultaneous in situ remediation of
contaminated ground water and soil with no air
emissions.
This technology is suitable for removing VOCs,
including chlorinated hydrocarbons, in ground
water and soil. AquaDetox is capable of
effectively removing over 90 of the 110 volatile
compounds listed in 40 CFR Part 261, Appendix
VIII.
AquaDetox is a high efficiency, countercurrent
stripping technology developed by Dow
Chemical Company. A single-stage unit will
typically reduce up to 99.99 percent of VOCs
from water. The SVE system uses a vacuum to
treat a VOC-contaminated soil mass, inducing a
flow of air through the soil and removing vapor
phase VOCs with the extracted soil gas. The
soil gas is then treated by carbon beds to
remove additional VOCs and reinjected into the
ground. The AquaDetox and SVE system share
a granulated activated carbon (GAC) unit.
Noncondensable vapor from the AquaDetox
system is combined with the vapor from the SVE
compressor and decontaminated by the GAC
unit. By-products of the system are a free-phase
recyclable product and treated water. Mineral
regenerable carbon will require disposal after
approximately three years..
A key component of the closed-loop system is a
vent header unit designed to collect the
noncondensable gases extracted from the
ground water or air that may leak into the portion
of the process operating below atmospheric
pressure. Furthermore, the steam used to
regenerate the carbon beds is condensed and
treated in the AquaDetox system.
Technology Performance
This system is currently being used at an
aeronautical systems facility in Burbank,
California, to treat ground water contaminated
with as much as 2,200 ppb of TCE and 11,000
ppb PCE, and soil gas with a total VOC
concentration of 6,000 ppm. Contaminated
ground water is being treated at a rate of up to
1,200 gpm while soil gas is removed and treated
at a rate of 300 cfrri. The system occupies
approximately 4,000 square feet. ;
This technology was also tested in a SITE
demonstration in September 1990. EPA is
currently preparing demonstration results and
expects to make these results available in early
1991.
Remediation Costs
Cost information is not available.
General Site Information
The AWD AquaDetox/SVE system is currently
being used at the Lockheed Aeronautical
Systems Company in Burbank, California. In
addition, EPA conducted a SITE demonstration
of the technology in September 1990 as part of
an ongoing remediation effort at the San
Fernando Valley Ground-Water Basin Superfund
site in Burbank, California.
Contacts
EPA Project Managers:
Norma Lewis and Gordon Evans
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U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7665 and 513/569-7684
FTS: 684-7665 and FTS: 684-7684
Technology Developer Contact:
David Bluestein
AWD Technologies, Inc.
49 Stevenson Street, Suite 600
San Francisco, California 94105
415/227-0822
Federal Remediation Technologies Roundtable
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0
Vapor Extraction
Terra Vac In Situ Vacuum Extraction
VOCs in Soils
Technology Description
The Terra Vac in situ vacuum extraction
technology can be used to remove and treat
volatile organic compounds (VOCs) from the
vadose or unsaturated zone of soils. This
technology is applicable to organic compounds
that are volatile or semivolatile at ambient
temperatures in soils and ground water. Often,
these compounds can be removed from the
vadose zone before they contaminate ground
water. Contaminants must have a Henry's
constant of 0.001 or higher for effective removal.
During the in situ vacuum extraction process, a
well is used to extract soil gas containing
organic contaminants like trichloroethylene
(TCE). The extracted contaminant stream
passes through a vapor/liquid separator, and the
resulting off-gases undergo treatment, before
being released into the atmosphere. Removing
VOCs from the vadose zone using a vacuum is
a patented process.
The technology does not require soil excavation
and is not limited by depth. The technology
works best at sites that are contaminated by
liquids with high vapor pressures. The success
of the system depends on site conditions, soil
properties, and the chemical properties of the
contaminants. The process works in soils of low
permeability (clays) if the soil has sufficient air-
filled porosity. Depending on the soil type and
the depth to ground water, the radius of
influence of a single extraction well can range
from tens to hundreds of feet.
The technology uses readily available equipment
such as extraction and monitoring wells,
manifold piping, a vapor/liquid separator, a
vacuum pump, and an emission control device,
such as an activated carbon canister. Once a
contaminated area is completely defined, an
extraction well is installed and connected by
piping to a vapor/liquid separator device. A
vacuum pump draws the subsurface
contaminants through the well, to the separator
device, and through a treatment system
consisting of activated carbon or a catalytic
oxidizer before the air stream is discharged to
the atmosphere. Subsurface vacuum and soil
vapor concentrations are monitored using
vadose zone monitoring wells.
Typical contaminant recovery rates range
between 20 and 2,500 pounds per day, and are
a function of the degree of contamination at the
site. Typically, the more volatile the organic
compound, the faster the process works. The
process is cost-effective at sites where
contaminated soils are predominantly above or
below the water table; dual vacuum extraction
systems have been designed for both vapor and
ground-water recovery.
Technology Performance
An in situ vacuum extraction demonstration at
the Groveland Wells Superfund site used four
extraction wells to pump contaminants to the
process system. Four monitoring wells were
used to measure the impact of treatment on site
contamination. During the SITE demonstration,
1,300 pounds of volatile organics, mainly TCE,
were extracted during a 56-day operational
period. The volatiles were removed from both
highly permeable strata and low permeability
clays. The process achieved nondetectable
levels of VOCs in the soil at some locations at
the test area. The VOC concentration in soil gas
was reduced 95 percent.
The Terra Vac system was also tested at several
other Superfund and non-Superfund sites.
These field evaluations yielded several
conclusions:
• The process represents a viable
technology to fully remediate a site
contaminated with volatile organic
compounds. Cleanup to non-detectable
levels in soil can be achieved under
certain conditions;
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The two major considerations in applying
this technology are the volatility of the
contaminants (i.e., Henry's constant) and
the site soil porosity;
The process performed well in removing
volatile organic compounds from soil with
measured permeabilities of 10"4 to 10"
8 cm/sec;
Pilot demonstrations are necessary at
sites with complex geology or contaminant
distributions; and
Remediation Costs
Based on available data, treatment costs are
typically $40 per ton of contaminated soil, but
can range between $10 and $150 per ton
depending upon requirements for off-gas or
wastewater treatment.
General Site Information
EPA first applied this technology at a Superfund
site in Puerto Rico, where carbon tetrachloride
had leaked from an underground storage tank.
In situ vacuum extraction processes have been
used at more than 100 waste sites across the
United States, such as the Verona Wells
Superfund Site in Battle Creek, Michigan, which
contains trichloroethylene and contaminantsfrom
solvent storage and spills. The SITE Program
performed a field demonstration of the process
at the Groveland Wells Superfund site in
Groveland, Massachusetts, ' which was
contaminated with TCE. EPA published the
Technology Evaluation Report and Applications
Analysis Report.
Contacts
EPA Project Manager:
Mary K. Stinson
U.S. EPA
Risk Reduction Engineering Laboratory
Woodbridge Avenue
Edison, New Jersey 08837
908/321-6683
FTS: 340-6683
Technology Developer Contact:
James Malot
Terra Vac, Inc.
356 Fontaleza Street
P.O. Box 1591
San Juan, Puerto Rico 00903
809/723-9171
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Vapor Extraction
Vacuum-Induced Soil Venting
Gasoline in Unsaturated Soil
Technology Description
The vacuum-induced venting process provides
in situ cleanup of gasoline contamination above
and below the water table. It reduces
contamination to levels low enough to eliminate
further leaching or desorption of gasoline into
the ground water. This technology can be
applied to hydrocarbon fuels in unsaturated soil.
A vapor/ground-water extraction well, and a well
for monitoring the vacuum induced venting were
installed in the gas spill area. The vapor
extraction/monitor wells each have five
individually screened intervals in the unsaturated
zone and two screened intervals below the water
table. A vacuum-extraction system with thermal
oxldizer is installed using one well to remediate
the spill area. The vacuum-extraction system
operates with a vacuum of between 20-25 inches
of mercury and with a flow rate of approximately
60 cfm. The present system uses an open pipe
at the top of an air-driven pump, which is
manually adjusted to follow the gasoline water
interface. Both wells are used for skimming
gasoline.
Technology Performance
Results from testing the vacuum-induced soil
venting technology at the Department of
Energy's (DOE) Lawrence Livermore National
Laboratory (LLNL) are positive:
• Approximately 100 gallons of free product
have been removed with this system;
• Approximately 5000 gallons of gasoline
have been removed through vacuum-
induced venting through the calendar year
1989;
• Over the calendar year 1989, total fuel
hydrocarbon concentrations (measured at
the inlet of the thermal oxidizer), have
decreased from 16,000 ppm in January
1989 to about 3,000-4,000 ppm at year
end; and
The thermal oxidizer that destroys the
gaseous hydrocarbons as they are
removed has operated with a 99.8 percent
destruction efficiency.
Remediation Costs
Cost information is not available.
General Site Information
Prior to 1979, approximately 17,000 gallons of
regular gasoline leaked into the soil and ground
water from an underground fuel storage tank at
the DOE's Lawrence Livermore National
Laboratory. Vacuum-induced venting was
demonstrated at this site as a method to clean
the gasoline contamination in situ.
Contacts
DOE, Lawrence Livermore National Laboratory
University of California
P.O. Box 808
Livermore, California 94550
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Soil Washing
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Soil Washing
BEST Solvent Extraction
Hydrocarbons and Other Organic Containments in Soils and Sludges
Technology Description
This BEST process is a mobile solvent extraction
system that uses one or more secondary or
tertiary amines, usually triethylamine (TEA), to
separate hydrocarbons from soils and sludges.
This technology is applicable for most organics
or oily contaminants in sludges or soils,
including polychlorinated biphenyls (P.CBs) (see
Table 1).
Solvent extraction is potentially effective in
treating the contaminants by separating the
sludges into three fractions: oil, water, and
solids. As the fractions separate, contaminants
are partitioned into specific phases. For
example, PCBs are concentrated in the oil
fraction, while metals are separated into the
solids fraction. The overall volume and toxicity of
the original waste solids are thereby reduced
and the concentrated waste streams can be
efficiently treated for disposal.
The BEST technology is based on the fact that
TEA is completely soluble in water at
temperatures below 20° C. Because TEA is
flammable in the presence of oxygen, the
treatment system must be sealed from the
atmosphere and operated under a nitrogen
blanket. Prior to treatment, it is necessary to
raise the pH of the waste material to greater than
10, creating an environment where TEA will be
effectively conserved for recycling through the
process. This pH adjustment may be
accomplished by adding sodium hydroxide.
Pretreatment also includes screening the
contaminated feed solids to remove cobbles and
debris for smooth flow through the process.
The BEST process begins by mixing and
agitating the cold solvent and waste in a
washer/dryer. The washer/dryer is a horizontal
steam-jacketed vessel with rotating paddles.
Hydrocarbons and water in the waste
simultaneously solvate with the cold TEA,
creating a homogeneous mixture. As the solvent
breaks the oil-water-solid bonds in the waste, the
solids are released and allowed to settle by
gravity. The solvent mixture is decanted and fine
particles are removed by centrifuging. The
resulting dry solids have been ciea'nsed of
hydrocarbons but contain most of the original
waste's heavy metals, thus requiring further
treatment prior to disposal.
The liquids from the washer/dryer vessels,
containing the hydrocarbons and water extracted
from the waste, are heated. As the temperature
of the liquids increases, the water separates from
the organics and solvent. The organics-solvent
fraction is decanted and sent to a stripping
column, where the solvent is recycled and the
organics are discharged for recycling or
disposal. The water phase is passed to a
second stripping column, where residual solvent
is recovered for recycling. The water is typically
discharged to a local wastewater treatment plant.
Technology Performance
The BEST technology is modular, allowing for
on-site treatment. Performance of the BEST
solvent extraction process can be influenced by
the presence of detergents and emulsifiers, low
pH materials and reactivity of the organics with
the solvent. Based on the results of many
bench-scale treatability tests conducted at the
General Refining Superfund site, the process
significantly reduces the hydrocarbon
concentration in the solids.
Other advantages of the technology include the
production of dry solids, the recovery and reuse
of soil, and waste volume reduction. By
removing organic contaminants, the process
reduces the overall toxicity of the solids and
water streams. It also concentrates the
contaminants into a smaller volume, allowing for
efficient final treatment and disposal.
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Remediation Costs
Cost information is not available.
General Site Information
The first full-scale BEST unit was used at the
General Refining Superfund site in Garden City,
Georgia. This solvent extraction technology is
the selected remedial action at the Pinnete's
Salvage site in Maine and is the preferred
alternative at the F. O'Connor site in Maine. The
demonstration of the BEST process under the
SITE Program is pending selection of an
appropriate site.
Contacts
EPA Project Manager:
Edward Bates
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7774
FTS: 684-7774
Technology Developer Contact:
Paul McGough
Resources Conservation Company
3006 Northup Way
Bellevue, Washington 98004
206/828-2400
TABLE 1
SPECIFIC WASTES CAPABLE OF TREATMENT
USING SOLVENT EXTRACTION
RCRA Listed Hazardous Wastes
Creosote-Saturated Sludge
Dissolved Air Flotation (DAF) Float
Slop Oil Emulsion Solids
Heat Exchanger Bundle Cleaning Sludge
API Separator Sludge
Tank Bottoms (Leaded)
Non-Listed Hazardous Wastes
Primary Oil/Solids/Water Separation Sludges
Secondary Oil/Solids/Water Separation Sludges
Bio-Sludges
Cooling Tower Sludges
HF Alkylation Sludges
Waste FCC Catalyst
Spent Catalyst
Stretford Unit Solution
Tank Bottoms
Treated Clays
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Soil Washing
Biogenesis Soil Cleaning Process
Hydrocarbons in Soil
Technology Description
The BioGenesis™ process uses a specialized
truck, gravity and cyclone separators, and a
bioreactor to wash hydrocarbon-contaminated
soil. The wash rate for hydrocarbon
contamination up to 5,000 ppm is 25 tons per
hour; higher contamination levels require slower
wash rates. After the first wash, 100 to 200 ppm
of the residuals remain. A second wash reduces
residuals even further. A single wash removes 95
to 99 percent of hydrocarbon concentrations up
to 16,000 ppm. One or two additional washes
are used for concentrations up to 45,000 ppm.
The residuals biodegrade at an accelerated rate
due to contact with BioVersal™, a light, alkaline,
organic formula used to reduce oil
contamination. Twenty-five tons of contaminated
soil are dumped into a mixture of water and
BioVersal™. For 15 to 30 minutes, aeration
equipment agitates the mixture, washing the soil
and encapsulating oil molecules with
BioVersal™.
After washing, the liquid products are recycled
or treated, and the soil is dumped out of the soil
washer. The bioreactor processes the minimal
amount of wastewater produced by the soil
washer. Recovered oils are recycled. PCBs,
metals, and other hazardous materials are
extracted in the same manner, then processed
using specific treatment methods. All equipment
is mobile, and treatment is normally on-site.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Diana Guzman
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7819
FTS: 684-7819
Technology Developer Contact:
Mohsen C. Amiran
BioVersal USA, Inc.
1703 Victoria Drive
Suite 303
Mount Prospect, Illinois 60056
708/228-7316
or
Charles L. Wilde
10626 Beechnut Court
Fairfax Station, Virginia 22039
703/250-3442
Technology Performance
This technology is used commercially in Europe.
It is applicable to soil contaminated with volatile
and nonvolatile hydrocarbons. These include
asphaltenes, polychlorinated biphenyis (PCBs),
polycylic hydrocarbons, and epichlorhydrin.
This technology was accepted into the SITE
Program in July 1990.
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Soil Washing
Biotrol Soil Washing System
Wood Preserving Wastes, Petroleum Hydrocarbons, Pesticides, PCBs,
Industrial Chemicals, and Metals in Soil
Technology Description
The Biotrol Soil Washing System is a patented,
water-based, volume reduction process for
treating excavated soil contaminated with wood
preserving wastes, petroleum hydrocarbons,
pesticides, polychlorinated biphenyls (PCBs),
various industrial chemicals, and metals. This
soil washing technology may be used to treat
fine grained soils (silt, clay, and soil organic
matter) and coarse grained soils (sand and
gravel). The objective of the process is to
concentrate the contaminants in a smaller
volume of material separate from a washed soil
product, with the goal that this soil product meet
appropriate cleanup standards.
After debris is removed, soil is mixed with water
and subjected to various unit operations
common to the mineral processing industry.
Process steps can include mixing trommels, pug
mills, vibrating screens, froth flotation cells,
attrition scrubbing machines, hydrocyclones,
screw classifiers, and various dewatering
operations. The core of the process is a multi-
stage, counter-current, intensive scrubbing
circuit with interstage classification. The
scrubbing action disintegrates soil aggregates,
freeing contaminated fine particles from the
coarser sand and gravel. In addition, surficial
contamination is removed from the coarse
fraction by the abrasive scouring action of the
particles themselves. Contaminants may also be
solubilized as dictated by solubility
characteristics or partition coefficients.
The efficiency of soil washing can be improved
using surfactants, detergents, chelating agents,
pH adjustment, or heat. In many cases,
however, water alone is insufficient to achieve
the desired level of contaminant removal while
minimizing cost. The volume of material
requiring additional treatment or disposal is
reduced significantly by separating the washed,
coarser soil components from the process water
and contaminated fine particles. The
contaminated residual products can be treated
by other methods. Process water is normally
recycled after biological or physical treatment.
Options for the contaminated fines can include
off-site disposal, incineration, stabilization, or
biological treatment.
This technology was initially developed to clean
soils contaminated with wood preserving wastes
such as polyaromatic hydrocarbons (PAHs) and
pentachlorophenol (PCP). However, the
technology is also applicable to soils
contaminated with petroleum hydrocarbons,
pesticides, polychlorinated biphenyls (PCBs),
various industrial chemicals, and metals.
Technology Performance
During the SITE demonstration of this technology
at the MacGillis & Gibbs Superfund site, a pilot-
scale unit with a treatment capacity of 500
pounds per hour was operated 24 hours per day
during the demonstration. Feed for the first
phase of the demonstration (two days) consisted
of soil contaminated with 170 ppm PCP and 240
ppm total PAHS. During the second phase
(seven days), soil containing 980 ppm PCP and
340 ppm total PAHs was fed to the system.
Contaminated process water from soil washing
was treated biologically in a fixed film reactor
and recycled. A three-stage, pilot-scale EIMCO
Biolift™ reactor system, supplied by the EIMCO
Process Equipment Company, was used to
biologically treat a portion of the contaminated
fines generated during soil washing.
Preliminary demonstration results showed that
PCP levels in the washed soil were reduced by
91 to 93 percent. Biological treatment reduced
PCP levels in the process water by 89 to 94
percent. Removal efficiencies increased as the
test proceeded. Near the completion of the test,
PCP removal was about 92 percent, while PAH
removal ranged from 86 to 99 percent.
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Remediation Costs
Cost information is not available.
General Site Information
EPA conducted the SITE demonstration of this
soil washing technology from September 25 to
October 27, 1989 at the MacGillis & Gibbs
Superfund site in New Brighton, Minnesota. EPA
expects to release the demonstration reports in
the first quarter of 1991.
Contacts
EPA Project Manager:
Mary K. Stinson
U.S. EPA
Risk Reduction Engineering Laboratory
Woodbridge Avenue
Edison, New Jersey 08837
908/321-6683
FTS: 340-6683
Technology Developer Contact:
John K. Sheldon
BioTrol, Inc.
11 Peavey Road
Chaska, Minnesota 55318
612/448-2515
Fax: 612/448-6050
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v
.m.
Soil Washing
Debris Washing System
Hazardous Chemicals in Solid Debris
Technology Description
EPA's Risk Reduction Engineering Laboratory
(RREL) staff and PEI Associates, Inc. developed
the Debris Washing System (DWS) to
decontaminate debris currently found at
Superfund sites throughout the country. The
DWS can be applied on-site to various types of
debris (metallic, masonry, or other solid debris)
contaminated with hazardous chemicals such as
pesticides, polychlorinated biphenyls (PCBs),
lead, and other metals. EPA demonstrated the
Debris Washing System under EPA's Innovative
Technology Program and PEI Associates, Inc.
will commercialize the technology.
The DWS consists of 300-gallon spray and wash
tanks, surfactant and rinse water holding tanks,
and an oil/water separator. The decontamination
solution treatment system includes a
diatomaceous earth filter, an activated carbon
column, and an ion exchange column. The DWS
unit is transported on a 48-foot semitrailer. At
the treatment site, the DWS unit is assembled on
a 25 by 24 foot concrete pad and enclosed in a
temporary shelter.
The DWS process operates by placing a basket
of debris in the spray tank with a forklift where it
is sprayed with an aqueous detergent solution.
An array of high pressure water jets blast
contaminants and dirt from the debris.
Detergent solution is continually recycled
through a filter system that cleans the liquid.
The wash and rinse tanks are supplied with
water at 140° F, at 60 psig. The contaminated
wash solution is collected and treated prior to
discharge. An integral part of the technology is
treatment of the process detergent solution and
rinse water to reduce the contaminant
concentration to allowable discharge levels.
Process water treatment consists of particulate
filtration, activated carbon adsorption and ion
exchange. Approximately 1,000 gallons of liquid
are used during the decontamination process.
Technology Performance
During the first pilot-scale testing at the Region
V Carter Industrial Superfund site, PCB
reductions averaged 58 percent in batch 1 and
81 percent in batch 2. RREL and PEI then
incorporated design changes and tested these
changes on the unit, prior to additional field
testing.
Field-testing of the upgraded pilot-scale DWS
unit conducted at a Region IV Superfund site
yielded promising results. PCB levels on the
surfaces of metallic transformer casings were
reduced to less than or equal to 10 micrograms
PCB/100 cm2. All 75 contaminated transformer
casings on-site were decontaminated to U.S.
EPA acceptable cleanup criteria and sold to a
scrap metal dealer.
The unit also was field tested at a site
contaminated with Dicamba and benzonitrile.
During the test, fifty-five gallon drums were cut
into sections, placed in the DWS, and carried
through the decontamination process. Results
from this study are currently being prepared.
Remediation Costs
Cost information is not available.
General Site Information
RREL performed the first pilot-scale testing at the
Region V Carter Industrial Superfund site in
Detroit, Michigan. RREL field tested the unit
using the upgraded pilot-scale DWS unit at a
Region IV PCB-contaminated Superfund Site in
Hopkinsville, Kentucky, during December 1989.
RREL also field tested the unit at the Shaver's
Farm site in Walker County, Georgia.
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Contacts
EPA Project Manager:
Naomi Barkley
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7854
FTS: 684-7854
Technology Developer Contact:
Michael L. Taylor
PEI Associates, Inc.
11499 Chester Road
Cincinnati, Ohio 45246
513/782-4801
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Soil Washing
Ghea Associates Process
Inorganic and Organic Contaminants in Soil
Technology Description
The Ghea Associates process uses selected
surfactants (detergent-like chemicals) in a water
solution to extract both inorganic and organic
contaminants from the soil. The technology is
applicable to mixtures of widely varying
compositions, including organic, inorganic,
volatile, and nonvolatile contaminants. The
resulting mixture is purified by separating out the
surfactant/contaminant complex and splitting it
into a surfactant fraction, which is recovered for
repeated use and a contaminants fraction.
The cleaning power of surfactants comes from
the presence of both hydrophilic ("water-liking")
and lipophilic ("oil-liking") groups on the same
molecule. Therefore, surfactants can link an oily
contaminant with the water, pulling it from its
matrix the way laundry soap (a detergent) pulls
soil from cloth into the wash water. Surfactants
enable water to hold large quantities of oil
contaminants by forming "micelles," tiny capsules
of surfactant filled with the contaminant.
A variation of the process called "foam flotation,"
uses surfactants to form stable bubbles, which
can lift heavy particles to the top of the solution.
This process combines "foam flotation" with
ultrafiltration to achieve complete recovery of the
surfactants from the surfactant/contaminant
complex and the reduction of dissolved metals.
After extraction, solids are filtered out of the
washing solution. These solids are rinsed and
disposed of after they are confirmed to be pure.
The temperature or pH of the solution is
changed so that the surfactant/contaminant
separates from the water. The water is again
treated and recycled through the system or
discharged to the sewer. The surfactant is
separated from the contaminants and also
recycled. The contaminated fraction will be
disposed of according to federal regulations.
This process uses the appropriate surfactant or
surfactant mixtures to separate the contaminants
of interest. Dosages, mixing time, and the
precise means of separating the fraction of the
wash water will vary with the situation.
Technology Performance
Treatability tests conducted by Ghea Associates
have been promising. When tested with tar-
contaminated soil, the process was able to
remove more than 99 percent of the organic
materials and 65 to 85 percent of some metallic
contaminants from the matrix. Other treatability
tests using BTX in water, trinitrotoluene in water,
and gas and diesel fuel in soil have been equally
successful. ;
Remediation Costs
Cost information is not available.
General Site Information :
EPA accepted the technology into the SITE
Emerging Technologies Program in July 1990.
The developer is preparing the work plan and
quality assurance project plan for U.S. EPA
approval.
Contacts
EPA Project Manager:
Annette Gatchett
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7697
FTS: 684-7697
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Technology Developer Contact:
Itzhak Gotlieb
New-Jersey Institute of Technology
Department of Chemical Engineering
Newark, New Jersey 07102
201/596-5862
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Soil Washing
Soil Treatment with Extraksol
Organic Contaminants in Soil
Technology Description
The Sanivan Group has developed Extraksol, a
mobile solvent extraction technology which
extracts organic contaminants from solids. It has
been successfully tested in a number of pilot
projects on a range of contaminants, including
polychlorinated biphenyls (PCBs),
pentachlorophenol (PGP), polyaromatic
hydrocarbons (PAHs), monoaromatic
hydrocarbons (MAHs), pesticides, oils, and
hydrocarbons. The process extracts these
contaminants from the soil by using
nonchlorinated, non-persistent organic solvents,
which are regenerated by distillation. The
contaminants are concentrated in the distillation
residues.
The three treatment steps - soil washing, soil
drying, and solvent regeneration - occur on a
flatbed trailer. The extraction fluid (solvent) is
circulated through the contaminated matrix
within a tumbling vat to wash the soil.
Controlled temperature and pressure optimize
the washing procedure. Hot inert gas dries the
soil. The gas vaporizes the residual extract fluid
and carries it from the tumbling vat to a
condenser, where the solvent is again separated
from the gas. The now solvent-free gas is
reheated and reinjected into the soil as required
for complete drying. After the drying cycle, the
decontaminated soil may be returned to its
original location.
Distillation of the contaminated solvent achieves
two major objectives: (1) it minimizes the
amount of solvent required to perform the
extraction by regenerating it in a closed loop,
and (2) ft significantly reduces the volume of
contaminants requiring further treatment or off-
site disposal by concentrating them in the still
bottoms.
The Extraksol process has several soil
restrictions:
• Maximum clay fraction, 40 per cent;
• Maximum water content, 30 per cent;
• Maximum particle size if porous material,
2 inches; and
• Maximum particle size if non-porous
material, 1-2 feet.
Technology Performance
This technology was accepted into the SITE
program in June 1990. Plans are currently
underway to demonstrate this technology at a
Superfund site located in the northeastern part
of Maine in late Summer 1991.
Remediation Costs
Cost information is not available.
Contacts:
EPA Project Manager:
Mark Meckes
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268 \
513/569-7348
FTS: 684-7348
Technology Developer Contact:
Peter Z. Colak
Sanivan
7777 Boulevard L.H. Lafontaine
Anjou (Quebec)
H1K4E4
514/355-3351
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(9
Soil Washing
Solvent Extraction
Organics, Oil, and Grease in Wastewater, Soils, and Sludges
Technology Description
-This technology uses liquified gas solvent to
extract organics, oil, and grease from wastewater
or contaminated sludges and soils. Specifically,
this technology can be applied to waste
containing hydrocarbons, carbon tetrachloride,
chloroform, benzene, naphthalene, gasoline,
vinyl acetate, furfural, butyric acid, higher organic
acids, dichloroethane, oils and grease, xylene,
toluene, methyl acetate, acetone, higher
alcohols, butanol, propanol, phenol, heptane,
polychlorinated biphenyls (PCBs) and other
complex organics.
In this solvent extraction system, carbon dioxide
is the gas used for aqueous solutions, while
propane and/or butane is used for sediment,
sludges and soils (semisolids). First,
contaminated solids, slurrys or wastewaters are
fed into the extractor. Solvent (gas condensed
by compression) is also fed to the extractor,
making nonreactive contact with the waste.
Typically, more than 99 percent of the organics
are separated from the feedwaste.
Following phase separation of the solvent and
organics, treated water is removed from the
extractor while the mixture of solvent and
organics passes to the separator through a
valve, where pressure is partially reduced. In the
separator, the solvent is vaporized and recycled
as fresh solvent. The organics are drawn off
from the separator, and either reused or
diposed.
The extractor design is different for contaminated
wastewaters and semisolids. For wastewaters,
a tray tower contactor is used, whereas for
semisolids a series of extractor/decanters
operating countercurrently is employed.
Technology Performance
This technology was demonstrated concurrently
with dredging studies managed by the U.S.
Army Corps of Engineers. The CF Systems Pit
Cleanup Unit treated contaminated sediments
using a liquified propane and butane mixture as
the extraction solvent.
The following test results include the number of
passes made during each test and the
concentration of PCBs before and after each
test:
Extraction efficiencies were high, despite some
operating difficulties during the tests. The use of
treated sediment as feed to the next pass
caused cross-contamination in the system. Full
scale commercial systems are designed to
eliminate problems associated with the pilot
plant design.
The following conclusions were drawn from this
series of tests and other data:
• Extraction efficiencies of 90-98% were
achieved on sediments containing
between 350 and 2,575 ppm PCBs. PCB
concentrations were as low as 8 ppm in
the treated sediment;
• In the laboratory, extraction efficiencies of
99.9% have been obtained for volatile and
semivolatile organics in aqueous and
semi-solid wastes;
• Operating problems included solids being
retained in the system hardware and
foaming in receiving tanks. The vendor
identified corrective measures that will be
implemented in the full-scale commercial
unit; and
• Projected costs for PCB cleanups are
estimated at approximately $150 to $450
per ton, including material handling and
pre- and post-treatment costs. These
costs are highly sensitive to the utilization
factor and job size, which may result in
lower costs for large cleanups.
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Remediation Costs
Cost information is not available.
General Site Information
EPA tested the pilot-scale system on PCB-laden
sediments from the New Bedford
(Massachusetts) Harbor Superfund site in
September 1988. PCB concentrations in the
harbor ranged from 300 ppm to 2,500 ppm.
EPA published the Technology Evaluation Report
(TER) in early 1990 (EPA/540/5-90/002).
Commercial systems have been sold to Clean
Harbors in Braintree, Massachusetts, for
wastewater cleanup; and to Ensco in Little Rock,
Arkansas, for incinerator pretreatment. A unit is
in operation at Star Enterprise in Port Arthur,
Texas, treating API separator sludge to meet
Best Demonstrated and Available Technology
(BOAT) standards for organics.
Contacts
EPA Project Manager:
Laurel Staley
U.S. EPA
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7863 or FTS: 684-7863
Technology Developer Contact:
Chris Shallice
CF Systems Corporation
140 Second Avenue
Waltham, Massachusetts 02154
617/890-1200 (ext. 158)
Test2
Tests
Test 4
PCB
Passes
9
3
6
Concentration
Before
360 ppm
288 ppm
2575 ppm
After :
8 ppm
82 ppm
200 ppm ,
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Solidification /Stabilization
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Solidification/Stabilization
Chemfix Solidification / Stabilization Process
Solid Waste in Soil and Sludge
Technology Description
This solidification/stabilization process involves
an inorganic system in which soluble silicates
and silicate setting agents react with polyvalent
metal ions and other waste components to
produce a chemically and physically stable solid
material. This technology is suitable for
contaminated soil, sludge, and other solid
wastes. It can also be used for base, neutral, or
acid extractable organics of high molecular
weight, such as refinery wastes, creosote, and
wood-treating wastes. Additionally, solidification/
stabilization can be applied, to electroplating
wastes, electric arc furnace dust, and municipal
sewage sludge containing heavy metals such as
aluminum, antimony, arsenic, barium, beryllium,
cadmium, chromium, iron, lead, manganese,
mercury, nickel, selenium, silver, thallium, and
zinc.
The Chemfix solidification/stabilization process
operates by blending feed waste in the reaction
vessel with certain reagents that are dispersed
and dissolved throughout the aqueous phase.
The reagents react with polyvalent ions in the
waste. Inorganic polymer chains (insoluble
metal silicates) form throughout the aqueous
phase and physically entrap the organic colloids
within the microstructure of the product matrix.
The water-soluble silicates then react with
complex ions in the presence of a siliceous
setting agent, producing amorphous, colloidal
silicates (gels) and silicon dioxide, which acts as
a precipitating agent. Most of the heavy metals
in the waste become part of the silicate. Some
of the heavy metals precipitate with the structure
of the complex molecules. A very small
percentage (estimated to be less than one
percent) of the heavy metals precipitates
between the silicates and is not chemically
immobilized.
Because some organics may be contained in
particles larger than the colloids, all of the waste
is pumped through processing equipment,
creating sufficient shear to emulsify the organic
constituents. Emulsified organics are then
solidified and discharged to a prepared area,
where the gel continues to set. The resulting
solids, though friable, encase any organic
substances that may have escaped
emulsification.
The system can be operated at 5 to 80 percent
solids in the waste feed; water is added for drier
wastes. Portions of the water contained in the
wastes are involved in three reactions after
treatment: (1) hydration, similar to that of
cement reactions; (2) hydrolysis reactions; and
(3) equilibration through evaporation. There are
no side streams or discharges from this process.
Technology Performance
From fall 1989 through winter 1990, Chemfix
Technologies, Inc.'s subsidiary, Chemfix
Environmental Services, Inc. (CES), applied a
high solids CHEMSET®
reagent protocol approach to the treatment of
about 30,000 cubic yards of heavy metal-
contaminated waste. The technology met the
goal of reducing leachable hexavalent chromium
to below 0.5 ppm in the Toxicity Characteristic
Leaching Procedure (TCLP), as well as the goal
of producing a synthetic clay cover material with
low permeability (less than 1 x 10~6 cm/sec).
The technology also met the production goal of
exceeding 400 tons per day. This included
production during many subfreezing days in
December, January, and March.
The CES technology was also effective in
reducing the concentrations of lead and copper
in the TCLP extracts. The concentrations in the
extracts from the treated wastes were 94 to 99
percent less than those from the untreated
wastes. Total lead concentrations in the raw
waste approached 14 percent.
The CES solidification/stabilization technology
performed well in several areas:
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The volume of the excavated waste
material increased from 20 to 50 percent
as a result of treatment;
In the durability tests, the treated wastes
showed little or no weight loss after 12
cycles of wetting and drying or freezing
and thawing;
The unconfined compressive strength of
the wastes varied between 27 and 307 psi
after 28 days. Permeability decreased by
more than one order of magnitude;
The air monitoring data suggest there was
no significant volatilization of
polychlorinated biphenyls (PCBs) during
the treatment process; and
The treated waste matrix displays good
stability, a high melting point, and a friable
texture. The matrix may be similar to soil,
depending upon the water content of the
feed waste.
Remediation Costs
Cost information is not available.
General Site Information
The technology was demonstrated in March
1989 at the Portable Equipment Salvage
Company site in Clackamas, Oregon. EPA
published the preliminary results in the SITE
Demonstration Bulletin (October 1989), and also
released a single draft report describing the
demonstration and future application of this
technology. EPA released the final
demonstration report in early 1990. During the
summer of 1990, CES engaged in another high
solids project involving lead.
Contacts
EPA Project Manager:
Edwin Barth
U.S. EPA
Center for Environmental Research Information
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7669
FTS: 684-7669
Technology Developer Contact:
Philip N. Baldwin, Jr.
Chemfix Technologies, Inc.
Suite 620, Metairie Center
2424 Edenborn Avenue
Metairie, Louisiana 70001
504/831-3600
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01
O
Solidification/Stabilization
iM-TECH Solidification / Stabilization Process
Organic Compounds, Heavy Metals, Ore and Grease in Soil and Sludge
Technology Description
The IM-TECH solidification/stabilization process
immobilizes contaminants in soil or sludge by
binding them into a concrete-like, leach-resistant
mass. This treatment technology is suitable for
soil and sludge contaminated with organic
compounds, heavy metals, oil and grease.
These wastes can be treated together or
individually.
Contaminated soil or sludge can be excavated
and/or treated in situ. If excavated, the waste is
screened for oversized material and fed into a
field blending unit. The blending unit may
consist of concrete ready-mix trucks or huge
batch plants capable of blending 100 tons per
hour.
The solidification/stabilization process mixes
hazardous wastes, cement or flyash, water, and
a patented additive called Chloranan that
encapsulates organic and inorganic molecules.
First, the Chloranan and water are added to the
blending unit. Next, the waste is added and the
ingredients mixed for about one minute. Finally,
the cement or flyash is added and the whole
mass mixed for a final minute. After 12 hours,
the treated output hardens into a concrete-like
mass that binds and immobilizes the
contaminant.
Technology Performance
The comparison of results from the seven-day,
28-day, nine month, and 22-month soil sample
tests at Douglassville, Pennsylvania, are
generally favorable. The physical test results
were very good, with unconfined compressive
strength between 220 to 1570 psi. Very low
permeabilities were recorded, and the porosity of
the treated wastes was moderate. Durability test
results showed no change in physical strength
after the wet/dry and freeze/thaw cycles. The
waste volume increased by about 120 percent.
However, refinements on the technology now
restrict volumetric increases to the 15-25 percent
range. Using less additives reduces strength,
but toxicity reduction is not affected. There
appears to be an inverse relationship between
physical strength and the waste organic
concentration.
The results of the leaching tests were mixed.
The Toxicity Characteristic Leaching Procedure
(TCLP) results of the stabilized wastes were very
low; essentially all values of metals, volatile
organics and semivolatile organics were below
one ppm. Lead leachate concentrations
dropped by a factor of 200 to below 100 ppb.
Volatile and semivolatile organic concentrations,
however, did not change from the untreated soil
TCLP. Oil and grease concentrations were
greater in the treated waste TCLPs than in the
untreated waste, from less than two ppm up to
four ppm.
The IM-TECH solidification/stabilization
technology performed well in several areas:
• It solidified contaminated material with
high concentrations (up to 25 percent) of
organics; however, organic contaminants,
including volatiles and base/neutral
extractables, were not immobilized to any
significant extent;
• It immobilized heavy metals - in many
instances, leachate reductions were
greater than 100 fold;
• The physical properties of the treated
waste exhibited high unconfined
compressive strengths, low permeabilities,
and good weathering properties; and
• The volume of treated soil increased.
Remediation Costs
The process, based on tests at Douglassville,
Pennsylvania, was economical, with costs
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ranging from $40-60 per ton for processing
heavy metals waste, and between $75-100 per
ton for wastes with heavy organic content.
General Site Information
The technology was demonstrated in October
1987 at a former oil reprocessing plant in
Douglassville, Pennsylvania. The site contained
high levels of oil and grease (25 percent) and
heavy metals (2.2 percent lead), and low levels
of VOCs (100 ppm) and PCBs (75 ppm). A
Technology Evaluation Report (September 1988)
and Applications Analysis Report (May 1990)
describing the completed demonstration are
available from EPA's Center for Environmental
Research Information (CERI). A report on long-
term monitoring will be available by 1990.
Since the demonstration, the technology has
been used to remediate a sludge with 85
percent oil from a refinery lagoon in Alaska,
several organic sludges for refineries on the Gulf
Coast, and a California Superfund site
contaminated with very high levels of heavy
metals.
Contacts
EPA Project Manager:
Paul R. dePercin
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7797
FTS: 684-7797
Technology Developer Contact:
Ray Funderburk
IM-TECH
Route 1, Box 250
Oakwood, Texas 75855
1-800-227-6543
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o
Solidification/Stabilization
In Situ Solidification / Stabilization Process
Inorganic and Organic Compounds in Soil, Sediment, and Sludge
Technology Description
i .
This in situ solidification/stabilization process
immobilizes organic and inorganic compounds in
wet or dry soil, using reagents (additives) to
produce a cement-like mass. This technology
can be applied to soil, sediments, and sludge-
pond bottoms contaminated with organic
compounds and metals. The process has been
laboratory-tested on soil containing
polychlorinated biphenyls (PCBs),
pentachlorophenol, refinery wastes, and
chlorinated and nitrated hydrocarbons.
There are two basic components of this
technology: (1) Geo-Con's deep soil mixing
system (DSM), a system to deliver and mix the
chemicals with the soil in situ; and (2) a batch
mixing plant to supply the International Waste
Technologies' (IWT) proprietary treatment
chemicals. The DSM system can be used in
almost any soil type; however, mixing time
increases with fineness. It can be used below
the water table and in soft rock formations.
Large obstructions must be avoided.
The IWT additives generate a complex,
crystalline, connective network of inorganic
polymers. The structural bonding in the
polymers is mainly covalent. The process
involves a two-phased reaction in which the
contaminants are first compiexed in a fast-acting
reaction, and then in a slow-acting reaction,
where the building of macromolecules continues
over a long period of time. The amount of
additives used varies for each type of waste.
Treatability tests are recommended.
The DSM system involves mechanical mixing
and injection. The system consists of one set of
cutting blades and two sets of mixing blades
attached to a vertical drive auger, which rotates
at approximately 15 rpm. Two conduits in the
auger are used to inject the additive slurry and
supplemental water. Additive injection occurs on
the downstroke; further mixing takes place upon
auger withdrawal. The treated soil columns are
36 inches in diameter, and are positioned in an
overlapping pattern of alternating primary and
secondary soil columns.
Technology Performance
Testing of the technology's performance at a
PCB-contaminated site in Hialeah, Florida,
indicated promising results:
» Immobilization of PCBs appears likely, but
could not be confirmed because of low
PCB concentrations in the untreated soil.
Leachate tests on treated and untreated
soil samples showed mostly undetectable
PCB levels. Leachate tests performed one
year later on treated soil samples showed
no increase in PCB concentrations,
indicating immobilization.
• Sufficient data were not available to
evaluate the performance of the system
with regard to metals or other organic
compounds.
• Each of the test samples showed high
unconfined compressive strength, low
permeability, and low porosity. These
physical properties improved when
retested orie year later, indicating the
potential for long-term durability.
« The bulk density of the soil increased 21
percent after treatment. This increased
the volume of treated soil by 8.5 percent
and caused a small ground rise of one
inch per treated foot of soil.
« The unconfined compressive strength
(DCS) of the treated soil was satisfactory,
with values up to 1,500 pounds per
square inch (psi).
« The permeability of the treated soil was
satisfactory, decreasing four orders of
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magnitude compared to the untreated soil,
or 10"6 and 10~7 compared to 10~2 cm/sec.
• The wet/dry weathering test on treated
soil was satisfactory. The freeze/dry
weathering test of treated soil was
unsatisfactory.
• The microstructural analysis, scanning
electron microscopy (SEM), optical
microscopy, and x-ray diffraction (XRD),
showed that the treated material was
dense, non-porous, and homogeneously
mixed.
* The Geo-Con DSM equipment operated
reliably.
This technology demonstration site was
composed primarily of unconsolidated sand and
limestone. The demonstration yielded several
conclusions about the performance of the
technology:
• Microstructural analyses of the treated soil
indicated a potential for long-term
durability. High unconfined compressive
strengths and low permeabilities were
recorded.
• Data provided by IWT indicate some
immobilization of volatile and semivolatile
organics. This may be due to
organophilic clays present in the IWT
reagent. There are insufficient data to
confirm this immobilization.
• Performance data are. limited outside of
SITE demonstrations. The developer
modifies the binding agent for different
wastes. Treatability studies should be
performed for specific wastes.
Remediation Costs
Remediation costs for this process are estimated
at $194 per ton of contaminated soil for the one-
auger machine used in the demonstration, and
$111 per ton for a commercial four-auger
operation.
General Site Information
EPA conducted a SITE demonstration at a PCB-
contaminated site in Hialeah, Florida, in April
1988. Two 10 x 20-foot test sectors of the site
were treated, one to a depth of 18 feet, and the
other to a depth of 14 feet. Ten months after the
demonstration, EPA performed long-term
monitoring tests on the treated sectors. EPA
published the Technology Evaluation Report and
Applications Analysis Report.
Contacts
EPA Project Manager:
Mary K. Stinson
U.S. EPA, RREL
Woodbridge Avenue
Edison, New Jersey 08837
908/321-6683
Technology Developer Contacts:
Jeff P. Newton
International Waste Technologies
150 North Main Street, Suite 910
Wichita, Kansas 67202
316/269-2660
Brian Jasperse
Geo-Con, Inc.
P.O. Box17380
Pittsburgh, Pennsylvania 15235
412/856-7700
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Solidification/Stabilization
Soil-Cement Mixing Wall (S.M.W.)
Metals and Semivolatile Organic Compounds in Soil
Technology Description
The Soil-Cement Mixing Wall (S.M.W.)
technology involves the in situ fixation
stabilization . and solidification of soil
contaminated with metals and Semivolatile
organic compounds, including pesticides,
polychlorinated biphenyls (PCBs), phenols, and
polyaromatic hydrocarbons (PAHs). Multi-axis
overlapping hollow stem augers, mounted on a
crawler-type base machine, inject
solidification/stabilization agents and blend them
with the contaminated soil in situ.
The machine can treat 90 to 140 cubic yards of
soil per eight-hour shift at depths up to 100 feet.
The in situ solidification/stabilization technology
produces a monolithic block down to the
treatment depth. The volume increase ranges
from 10 to 30 percent, depending on the nature
of the soil matrix and the amount of fixation
reagents and water required for treatment.
This technique has been used in mixing soil,
cement, or chemical grout for more than 18
years on various construction applications,
including cutoff walls and soil stabilization.
Technology Performance
This project was accepted into the
Demonstration Program in June 1989.
selection is currently underway.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
S. Jackson Hubbard
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7507
FTS: 684-7507
Technology Developer Contact:
David S. Yang
S.M.W. Seiko, Inc.
100 Marine Parkway
Suite 350
Redwood City, California 94065
415/591-9646
SITE
Site
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o
Solidification/Stabilization
Solidification / Stabilization
Organics and Inorganics In Soil, Sludge, and Liquid
Technology Description
This solidification/stabilization technology applies
proprietary bonding agents to soil, sludge, and
liquid wastes containing volatile or semi-volatile
organic and inorganic contaminants to fix
pollutants within the wastes. The treated waste
is then mixed with cementitious materials and
placed in a stabilizing matrix. The specific.
reagents used are custom-selected based on the
particular waste to be treated. The resultant
material is a high-strength, non-leaching
monolith that can be placed into the ground.
This process uses standard engineering and
construction equipment. Since the type and
dose of reagents depend on the waste's
characteristics, treatability studies and site
investigations must be conducted to determine
the proper reagent mix. The process begins
with a front end loader and/or a backhoe
excavating the waste material.
Material containing large pieces of debris must
be prescreened. The waste is then placed, in
measured quantities, into a pug mill or other
mixer, where it is mixed with a controlled amount
of water and reagent. From there, the waste-
reagent mixture is transferred to the cement
batcher, where it is mixed with dry blends of a
pozzolanic mixture. The operation does not
generate waste byproducts.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Terry Lyons
U.S. EPA
Risk Reduction Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7589
FTS: 684-7589
Technology Developer Contact:
E. Benjamin Peacock
Wastech, Inc.
P.O. Box 1213
114TulsaRoad
Oak Ridge, Tennessee 37830
615/483-6515
Technology Performance
EPA is in the process of selecting a site for the
technology demonstration. To date, this
technology has treated a wide variety of waste
streams consisting of soil, sludge, and raw
organic streams, such as lubricating oil, aromatic
solvents, evaporator bottoms, chelating agents,
and ion exchange resins, with contaminant
concentrations ranging from parts per million
(ppm) levels to 40 percent by volume. The
technology can also be applied to mixed wastes
containing radioactive materials along with
organic and inorganic contaminants.
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I
o
Solidification/Stabilization
Solidification / Stabilization with Silicate Compounds
Organics and Inorganics in Ground Water, Soil, and Sludge
Technology Description
This technology uses silicate compounds to fix
and solidify soil and sludge contaminated with
metals, cyanide, fluorides, arsenates, ammonia,
chromates, and selenium in unlimited
concentrations. This technology also removes
organics from contaminated water. Higher
weight organics .in ground water, soil, and
sludge, including halogenated, aromatic, and
aliphatic compounds, can also be treated by this
process. However, the process is not as
successful for low molecular weight organics
such as alcohols, ketones, glycols, and volatile
organics. For soil and sludge, proprietary
silicate reagents selectively adsorb organic and
inorganic contaminants before the waste is
mixed with a cement-like material to form a high-
strength, non-leaching cement block (monolith).
For water, the same reagents can be used in
conjunction with granular activated carbon to
remove organics from the ground water. The
resulting waste material is then solidified by the
first technology.
In this combined technology, the type and dose
of reagents depend on the waste characteristics.
Treatability studies and site investigations are
conducted to determine reagent formulations.
The process begins with pretreatment of the
contaminated waste material. Coarse material is
separated from fine material and sent through a
shredder or crusher to reduce the material to the
size required for the solidification technology.
The waste is then loaded into a batch plant,
weighed, and the proportional amount of silicate
reagent is added. This mixture is conveyed to a
concrete mixing truck, pug mill or other mixing
equipment where water is added and the mixture
is thoroughly blended. The treated material is
then placed in a confining pit on-site for curing,
or cast into molds for transport and disposal off-
site.
A self-contained mobile filtration pilot facility is
used to treat organic-contaminated ground
water. The contaminated • water is passed
through a column filter containing the silicate
reagent to separate the high molecular weight
organics from the water. The effluent from this
column filter is then passed through a second
column filter containing granulated activated
carbon to remove the low molecular weight
organics.
Technology Performance
A demonstration of this technology was
scheduled to occur during October or November
1990 at a wood treating site near Fresno,
California. Contaminants at the site include
pentachlorophenol, chromium, copper, and
arsenic. Results are currently unavailable.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Edward R. Bates
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7774
FTS: 684-7774
Technology Developer Contact:
Steve Pegler
Silicate Technology Corporation
Scottsdale Technology Center, Suite B2
7650 East Redfield Road
Scottsdale, Arizona 85260
602/941-1400
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SB
o
Solidification/Stabilization
Soliditech Solidification / Stabilization Process
Organic and Inorganic Compounds, Metals, Ore and
Grease in Soil and Sludge
Technology Description
This solidification/stabilization process
immobilizes contaminants, particularly organic
compounds, metals, inorganic compounds, and
oil and grease, in soil and sludge by binding
them in a concrete-like, leach-resistant matrix.
Wastes treated during the demonstration were
soil, filter cake, and oily wastes from an old
storage tank. These wastes were contaminated
with petroleum hydrocarbons, polychlorinated
biphenyls (PCBs), other organic chemicals, and
heavy metals. Batch mixers of various capacities
are available to treat different volumes of waste.
Contaminated waste materials are collected,
screened to remove oversized material, and
introduced to the batch mixer. The waste
material is then mixed with: (1) water;
(2) Urrichem, a proprietary chemical reagent; (3)
proprietary additives; and (4) pozzolanic material,
kiln dust, or cement; cement was used for the
demonstration. Once thoroughly mixed, the
treated waste is discharged from the mixer.
Technology Performance
The Soliditech demonstration at the Imperial Oil
Company/Champion Chemical Company
Superfund site in Morganville, New Jersey,
presented several key findings:
• Chemical analyses of extracts and
leachates showed that heavy metals
present in the untreated waste were
immobilized;
• Solid and liquid wastes with high organic
content (up to 17 percent) as well as oil
and grease were solidified;
• Volatile organic compounds in the original
waste were not detected in the treated
waste;
Treated waste is a solidified mass with
significant unconfined compressive
strength, high stability, and a rigid texture
similar to that of concrete. Physical test
results of the solidified waste samples
showed: (1) unconfined compressive
strengths ranged from 390 to 860 psi; (2)
very little weight loss after .12 cycles of
wet/dry and freeze/thaw durability tests;
(3) low permeability of the treated waste;
and (4) increased density after treatment;
The solidified waste increased in volume
by an average of 22 percent. The bulk
density of the waste material increased by
approximately 35 percent due to
solidification;
Semivolatile organic compounds (phenols)
were detected in the treated waste and
the Toxicity Characteristic Leaching
Procedures (TCLP) extracts from the
treated waste but not in the untreated
waste or its TCLP extracts. The presence
of these compounds is believed to result
from chemical reactions in the waste
treatment mixture;
Oil and grease content of the untreated
waste ranged from 2.8 to 17.3 percent
(28,000 to 173,000 ppm). Oil and grease
content of the TCLP extracts of the
solidified waste ranged from 2.4 to 12
ppm;
The pH of the solidified waste ranged from
11.7 to 12.0. The pH of the untreated
waste ranged from 3.4 to.7.9;!
PCBs were not detected in any extracts or
leachates of the treated waste; and
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• Visual observation of solidified waste
showed dark inclusions approximately 1
mm in diameter. Ongoing microstructural
studies are expected to confirm that these
inclusions are encapsulated wastes.
A Technology Evaluation Report was published
in February 1990 in two volumes: Volume I
(EPA/540/5-89/005A) is the report itself and
Volume II (EPA/540/5-89/005B) contains the data
that accompanies the report. An Applications
Analysis Report was scheduled for publication in
late November 1990.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Walter E. Grube, Jr.
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7798
FTS: 684-7798
Technology Developer Contact:
Bill Stallworth
Soliditech, Inc.
1325 S. Dairy Ashford, Suite 385
Houston, Texas 77077
713/497-8558
General Site Information
EPA demonstrated the Soliditech process in
December 1988 at the .Imperial Oil
Company/Champion Chemical Company
Superfund site in Morganville, New Jersey. This
location formerly contained both chemical
processing and oil reclamation facilities.
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C3
Solidification/Stabilization
Stabilization with Lime
Hydrocarbons and Organics in Sludge
Technology Description
This technology uses lime to stabilize acidic
sludge containing at least five percent
hydrocarbons (typical of sludge produced by
recycling lubricating oils). The technology can
also stabilize waste containing up to 80 percent
organics. The process tolerates low levels of
mercury and moderate levels of lead and other
toxic metals. No hazardous materials are used
in the process. The lime and other chemicals
are specially prepared to significantly improve
their reactivity and other key characteristics.
Sludge is removed from a waste pit using
conventional earthmoving equipment and mixed
with lime in a separate blending pit. The
temperature of the material in the blending pit
rises for a brief time to about 100° C, creating
some steam. After 20 minutes, almost all of the
material is fixed, however, the chemicals mixed
in the sludge continue to react with the waste for
days. The volume of the waste is increased by
30 percent by adding lime.
The fixed material is stored in a product pile until
the waste pit has been cleaned. The waste is
then returned to the pit and compacted to a
permeability of 10~10cm/sec.
Technology Performance
EPA is seeking a suitable site to demonstrate
this technology. A SITE demonstration is
planned for the spring or summer of 1991.
Remediation Costs
Cost information is not available.
Contacts !
EPA Project Manager:
Walter Grube
U.S. Environmental Protection Agency
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7798
FTS: 684-7798
Technology Developer Contact:
Joseph DeFranco
Separation and Recovery Systems, Inc.
1762 McGaw Avenue
Irvine, California 92714
714/261-8860
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Other Physical Treatment
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1
Other Physical Treatment
Carver-Greenfield Process for Extraction of Oily Waste
Oil-Soluble Hazardous Compounds in Sludge and Soil
Technology Description
The Carver-Greenfield Process® is designed to
separate materials into their constituent solid, oil
(including oil-soluble substances), and water
phases. It is primarily intended for soils and
sludges contaminated with oil-soluble hazardous
compounds. The technology uses a food-grade
"carrier oil" to extract the oil-soluble
contaminants. Pretreatment is necessary to
achieve particle sizes less than 3/8-inch.
The carrier oil, with a boiling point of 400° F,
typically is mixed with waste sludge or soil and
the mixture is placed in the evaporation system
to remove any water. The oil serves to fluidize
the mix and maintain a low slurry viscosity to
ensure efficient heat transfer, allowing virtually all
of the water to evaporate.
Oil-soluble contaminants are extracted from the
waste by the carrier oil. Volatile compounds
present in the waste are also stripped in this
step and condensed with the carrier oil or water.
After the water is evaporated from the mixture,
the resulting dried slurry is sent to a centrifuging
section that removes most of the carrier oil from
the solids.
After centrifuging, residual carrier oil is removed
by a process known as hydroextraction. The
carrier oil is recovered by evaporation and steam
stripping. The hazardous constituents are
removed from the carrier oil by distillation. This
stream can be incinerated or reclaimed. In some
cases, heavy metals in the solids will be
complexed with hydrocarbons and will also be
extracted by the carrier oil.
Technology Performance
The process has been successfully tested in a
pilot plant on refinery "slop oil," consisting of 72
percent water, and on a mixed refinery waste
consisting of dissolved air flotation sludge, API
separator bottoms, tank bottoms, and biological
sludge. EPA has identified the PAB Oil site in
Louisiana as a potential site for demonstrating
this technology. The PAB oil site contains
petroleum wastes and contaminated-soils, and a
demonstration was tentatively planned for
January 1991.
The Carver-Greenfield process can be used to
treat sludge, soil, and other water-bearing
wastes containing oil-soluble hazardous
compounds, including PCBs, PNAs, and dioxins.
The process has been commercially applied to
municipal wastewater sludge, paper mill sludge,
rendering waste, pharmaceutical plant sludge,
and many other wastes.
Contacts
EPA Project Manager:
Laurel Staley
U.S. EPA
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513-569-7863
FTS: 684-7863
Technology Developer Contact:
Thomas C. Holcombe
Dehydro-Tech Corporation
6 Great Meadow Lane
East Hanover, New Jersey 07936
201-887-2182
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Other Physical Treatment
Catalytic Decontamination
Volatile Organic Compounds (VOC) in Ground Water
Technology Description
This catalytic decontamination process is a
closed system that treats volatile organic
compounds in ground water producing
innocuous end products. This technology can
be useful when cross media transfer of the
contamination, which may occur with other
processes, such as air stripping, is
unacceptable. This technology is primarily a
ground-water restoration technique, although
surface water can be treated as well. It is
especially applicable for highly contaminated
waters such as leachates.
The ULTROX system used in the pilot study
consists of two "loops." The first loop consists of
air drying, ozone generation, and injection of the
ozone into the vapor-liquid contact tank. Air
effluent passes through a catalytic destruction
unit and returns to the air drier. The second
loop is open and consists of a water inlet from
the ground-water source, pretreatment,
introduction into the vapor-liquid contact tank,
and discharge. The water pretreatment might
consist of filtering, water softening, iron removal,
or defoaming.
This technology has a number of advantages:
• The process is closed circuit, .i.e., there is
no air effluent;
• It operates at negative air pressure, thus,
reducing the risk of accidental
contamination due to leaks; and
• It is a destructive, rather than a cross
media transfer technique.
Despite these advantages, this technology also
has limitations:
• The method might not be cost effective
with respect to methods that have air
effluents;
When treating high concentrations, a
potentially large consumption of ozone will
result;
When treating anoxic leachates, reduced
metal compounds are likely to be present;
These reduced metal compounds will
react with the ozone and can form
insoluble precipitates as well as result in
large ozone consumption;
The metal precipitates could require
extensive system cleaning;
The method requires considerable energy
for the generation of UV light, dry air,
ozone, pumps, and blowers; and
Biofouling can occur on the UV light
tubes.
Technology Performance
The results from a small-scale pilot test
conducted at Fort Dix, New Jersey were both
positive and negative:
• Although total organic carbon
concentration was not reduced, the
concentration of volatile halogenated
organics (VHO) was reduced up to 90
percent; and
• Without the inclusion of UV light in the
treatment, the VHO concentration was
reduced, but methylene chloride was not
affected and dichloroethanes were not
reduced below detection limits.
Remediation Costs
Based on limited experience to date, the
operating and maintenance costs of this method
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have not been developed in detail, but are
expected to be in the range of $1 to $8 per
1,000 gallons, depending upon the concentration
of the contaminants and the amount of
pretreatment required. Uninstalled equipment for
treating 50,000 gpd of ground water, with an
organic halide concentration in the range of 75
to 100 g/L, would cost in the range of $150,000
to $200,000.
General Site Information
A small-scale pilot testing (1 to 10 drums) has
been conducted at Fort Dix, New Jersey.
Contacts
Steve Maloney
USACERL
P.O. Box 4005
Champaign, IL 61820
217/373-6740
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o
Other Physical Treatment
Catalytic Ozone Oxidation
Organfcs and Inorganics in Soil, Solid, Sludge, Leachates, Ground Water
Technology Description
This technology is designed to treat soils with
organic and inorganic contaminants. The
technology is a two-stage process: the first
stage extracts the contaminants from the soil,
and the second stage oxidizes contaminants
present in the extract. The extraction is carried
out using ultrapure water and ultrasound.
Oxidation involves ozone, ultraviolet light, and
ultrasound. The treatment products of this
technology are decontaminated soil and inert
salts.
After excavation, contaminated soil is passed
through a 1-inch screen. Soil particles retained
on the screen are crushed using a hammermill
and sent back to the screen. Soil particles
passing through the screen are sent to a soil
washer, where ultrapure water extracts the
contaminants from the screened soil. Ultrasound
acts as a catalyst to enhance soil washing.
Typically, 10 volumes of water are added per
volume of soil, generating a slurry of about 10-20
percent solids. This slurry is conveyed to a
solid/liquid separator, such as a centrifuge" or
cyclone, to separate the decontaminated soil
from the contaminated water. The
decontaminated soil can be returned to its
original location or disposed of appropriately.
After the solid/liquid separation, any oil present
in the contaminated water is recovered using an
oil/water separator. The contaminated water is
ozonated prior to oil/water separation to aid in oil
recovery. The water then flows through a filter to
remove any fine particles. After the particles are
filtered, the water flows through a carbon filter
and a deionizer to reduce the contaminant load
on the multi-chamber reactor.
In the multi-chamber reactor, ozone gas,
ultraviolet light, and ultrasound are applied to the
contaminated water. Ultraviolet light and
ultrasound catalyze the oxidation of
contaminants by ozone. The treated water
(ultrapure water) flows out of the reactor to a
storage tank and is reused to wash another
batch of soil. If makeup water is required,
additional ultrapure water is generated on-site by
treating tap water with ozone and ultrasound.
This treatment system is also equipped with a
carbon filter to treat the off-gas from the reactor.
The carbon filters are biologically activated to
regenerate the spent carbon in-situ.
System capacities range from one cubic foot of
solids per hour, with a water flow rate of one
gallon per minute, to 27 cubic yards'of solids per
hour, with a water flow rate of 50 gallons per
minute. The treatment units available for the
SITE demonstration can treat 1 to 5 cubic yards
of solids per hour.
Technology Performance
This technology was tentatively scheduled for a
demonstration in late 1990. This technology can
be applied to soil, solid, sludge, leachates and
ground water containing organics such as PCB,
PCP, pesticides and herbicides, dioxins, and
inorganics, including cyanides. The technology
could effectively treat total contaminant
concentrations ranging from 1 ppm to 20,000
ppm. Soil and solids greater than 1 inch in
diameter need to be crushed prior to treatment.
Contacts
EPA Project Manager:
Norma Lewis
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513-569-7665 :
FTS: 684-7665
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Technology Developer Contact:
Lucas Boeve
Excalibur Enterprises, Inc.
314 West 53rd Street
New York, N.Y. 10019
212-484-2699
Florida Office:
3232 S.W. 2nd Avenue
Suite 107
Ft. Lauderdale, Florida 33315
305-763-9507
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4
ul
CJ
Other Physical Treatment
Chemtact™ Gaseous Waste Treatment
Organics and Inorganics in Waste Streams
Technology Description
The Chemtact™ system uses gas scrubber
technology to remove gaseous organic and
inorganic contaminants through efficient gas-
liquid contacting. This technology can be used
on gaseous waste streams containing a wide
variety of organic or inorganic contaminants, but
is best suited for volatile organic compounds.
The system is applicable for use with source
processes that generate a contaminated
gaseous exhaust, such as air stripping of ground
water or leachate, soil aeration, or exhausts from
driers or incinerators.
Droplets of a controlled chemical solution are
dispersed by atomizing nozzles within the
scrubber chamber. Very small droplet sizes
(less than 10 microns), along with a longer
retention time than traditional scrubbers, results
in a once-through system that generates low
volumes of liquid residuals. These residuals are
subsequently treated by conventional
techniques.
Gas scrubbing is a volume reduction technology
that transfers contaminants from the gas phase
to a liquid phase. The selection of absorbent
liquid is based on the chemical characteristics of
the contaminants.
Two mobile pilot units are currently available: a
two-stage, 800 cubic feet per minute (cfm)
system; and a one-stage, 2,500 cfm system.
This equipment is trailer-mounted and can be
transported to waste sites.
Technology Performance
EPA is currently locating a suitable site to
demonstrate this technology.
Contacts
EPA Project Manager:
Ronald Lewis
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513-569-7856
FTS: 684-7856 :
Technology Developer Contact:
Harold J. Rafson
Quad Environmental Technologies Corporation
3605 Woodhead Drive, Suite #103
Northbrook, Illinois 60062
312-564-5070
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Other Physical Treatment
Freezing Separation
Organics and Inorganics in Aqueous Streams
Technology Description
This freeze crystallization technology will remove
both organics and inorganics from contaminated
aqueous streams. It works on both surface
water and ground water, as well as directly on
process wastes and mixed (radioactive and
hazardous) wastes. Freeze technologies can
process all contaminant types in a single, stage.
It is also capable of concentrating residuals to
higher concentrations than other liquid
separation processes.
This process is applicable to free liquids,
whether the liquid is water or an organic solvent.
It can be used in conjunction with other
processes to treat wastes contained in non-
aqueous media. For example, contaminated
soils can be washed to transfer the contaminant
into a liquid medium. The low concentrations in
the washing medium are concentrated by
freezing to allow by-product recovery or more
economical final destruction.
The freeze crystallization process operates on
the principle that when water freezes, the crystal
structure that forms naturally excludes
contaminants from the water molecule matrix. In
this freeze crystallization process, refrigerant is
injected directly into the feed, thus, removing
heat until a phase change from liquid to solid is
achieved. Pure crystals of solute and solvent
form separately and are separated from each
other by gravity. The crystals are recovered and
washed with melt-water to remove any adhering
contaminants and then melted in a heat pump
cycle before being discharged from the plant.
Mixed liquid waste enters the system through the
feed heat exchanger, where it is cooled within a
few degrees of its freezing temperature. The
cooled feed then enters the crystallizer, where it
is mixed directly with boiling refrigerant. The
water molecules are crystallized in the stirred
solution and are maintained at a uniform ice
concentration by continuous removal of ice slurry
(a combination of ice crystals and liquid) from
the crystallizer. The slurry is pumped to a
eutectic separator (also called a growth tank)
where gravity segregates the crystal of solvent
and solute into different streams. A heat
pump/refrigeration cycle removes refrigerant
vapor from the crystallizer and compresses it so
that it will give up its heat to melt the purified
crystals.
Ice slurry from the growth tank is pumped to the
crystal separator, where ice crystals form a
porous pack. The liquid from the slurry is
drained by gravity from the wash column via
screened openings, and is then returned to the
growth tank to transport more ice. Hydraulic
forces generated by the flow of liquid to the
screens in the middle of the ice pack propel the
ice pack upward in the crystal separator. Melted
product is used to transport the ice to a
melter/condenser, where the slurry is melted and
where hot refrigerant gas is condensed.
All refrigerants are soluble in water to some
degree. Consequently, decanters and strippers
are used to remove this refrigerant from the melt,
the concentrate, and any other liquid phases
produced from the process prior to their
discharge from the plant. The strippers operate
under a vacuum and contain heaters that
generate low-pressure steam to enhance
refrigerant removal, if necessary.
Technology Performance
This project was accepted into the SITE
Demonstration Program in July 1988. Treatability
studies have been completed. A demonstration
of this technology was scheduled for early 1991
at the Stringfellow Superfund Site in Glen Avon,
California.
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Contacts
EPA Project Manager:
S.Jackson Hubbard
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513-569-7507
FTS: 684-7507
Technology Developer Contact:
James A. Heist
Freeze Technologies Corporation
2539-C Timberlake Road
P.O. Box 40968
Raleigh, North Carolina 27629-0968
919-850-0600
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ul
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Other Physical Treatments
Geosafe Process
Inorganics in Soils and Sludges
Technology Description
The Geosafe in situ vitrification (ISV) process can
be used to destroy or remove organics and/or
immobilize inorganics in contaminated soils or
sludges. Geosafe has performed more than 90
tests of various scales applying ISV on
polychlorinated biphenyl (PCB) wastes, industrial
lime sludge, dioxins, metal plating wastes and
other solid combustibles and liquid chemicals.
The ISV process uses an electrical network to
melt soil or sludge at temperatures of 1600 to
2000° C; thus, destroying organic pollutants by
pyrolysis. Inorganic pollutants are incorporated
within the vitrified mass, which has properties of
glass.
The vitrification process begins by inserting large
electrodes into contaminated zones containing
sufficient soil to support the formation of a melt.
An array (usually square) of four electrodes is
placed to the desired treatment depth in the
volume to be treated. Because soil typically has
low conductivity, flaked graphite and glass frit
are placed on the soil surface between the
electrodes to provide a starter path for electric
current. The electric current passes through the
electrodes and begins to melt soil at the surface.
As power is applied, the melt continues to grow
downward, at a rate of one to two inches per
hour. Individual settings (each single placement
of electrodes) may grow to encompass a total
melt mass of 1000 tons and a maximum width of
30 feet. Single setting depths as great as 30
feet are considered possible. Depths of 17 feet
have been achieved to date with the existing
large-scale ISV equipment. Adjacent settings
can be positioned to fuse to each other and to
completely process the desired volume at a site.
Stacked settings to reach deep contamination
are also possible.
Both the organic and inorganic airborne
pyrolysis byproducts are captured in a hood,
which draws the contaminants into an off-gas
treatment system that removes particulates and
other pollutants of concern. Air flow through the
hood is controlled to maintain a negative
pressure. An ample supply of air provides
excess oxygen for combustion of any pyrolysis
products and organic vapors from the treatment
volume. The off-gases, combustion products,
and air are drawn from the hood (by induced
draft blower) into the off-gas treatment system,
where they are treated in several ways: (1)
quenching; (2) pH controlled scrubbing; (3)
dewatering (mist elimination); (4) heating (for
dewpoint control); (5) patticulate filtration; and
(6) activated carbon adsorption (Figure 2).
Because the void volume present in particulate
materials (20-40 percent for typical soils) is
removed during processing, a. corresponding
volume reduction occurs. Volume is further
reduced as some materials present in the soil,
such as humus and organic contaminants, are
removed as gases and vapors during
processing.
The ISV system is mounted on three semi-trailers
for transport to a site. Electric power is usually
taken from a utility distribution system at
transmission voltages of 125 or 138 kilovolts
(kV); power may also be generated on-site by a
diesel generator. The electrical supply system
has an isolated ground circuit to provide
appropriate operational safety.
In saturated soils or sludges, the initial
application of the electric current must reduce
the moisture content before the vitrification
process can begin. This increases energy
consumption and associated costs. Also,
sludges must contain a sufficient amount of
glass-forming material (non-volatile, non-
destructible solids) to produce a molten mass
that will destroy or remove organic and
immobilize inorganic pollutants. The ISV process
is limited: (1) individual void volumes cannot
exceed 150 cubic feet; (2) rubble cannot exceed
10 percent by weight; and (3) combustible
organics in the soil or sludge cannot exceed 5-
10 weight percent, depending upon the heat
Federal Remediation Technologies Roundtable
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value. These limitations must be addressed for
each site.
Technology Performance
Based on tests conducted by the technology
vendor, the large-scale ISV system melts soil at
a rate of four to six tons per hour. After cooling,
the process results in the formation of a vitrified
silicate glass monolith with a microcrystalline
structure. This monolith possesses excellent
structural and environmental properties.
Remediation Costs
Cost information is not available.
Contacts
EPA Project Manager:
Teri Shearer
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7949
FTS: 684-7949 ' i
Technology Developer Contact:
James E. Hansen
Geosafe Corporation
303 Park Place, Suite 126
Kirkland, Washington 98033
206/822-4000
General Site Information
ISV technology has been selected as part of a
Record of Decision (ROD) or equivalent for use
at eight sites within the U.S. and one site in
Europe. EPA's SITE Program is planning a
technology demonstration at an unspecified site.
Contaminated
Soil Region
(1)
Vitrified Monolith
(2)
(3)
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Other Physical Treatments
In Situ Vitrification
Organics, Inorganics, and Radionuclides in Soils
Technology Description
The in situ vitrification (ISV) process fixes fission
products and immobilizes or destroys hazardous
chemicals in soils at mixed hazardous waste
sites. This technology can be applied to
radionuclides, heavy metals, and hazardous
organic-contaminated soil.
ISV is the conversion of contaminated soil into a
durable glass and crystalline waste form through
melting the soil by joule heating. Contaminants
are destroyed by or immobilized in molten glass
(melted soil). Soil is melted by electrical energy
from electrodes that are placed in the ground.
Off-gas from this process is treated by
conventional off-gas treatment methods.
This technology has a number of benefits.
Specifically, ISV may safely immobilize or destroy
both radioactive and hazardous chemicals
before they impact the ground water or other
ecosystems. It is applicable to soils
contaminated with fission products, transuranics,
hazardous metals, and hazardous organics. It
reduces the risk to the public by immobilizing or
destroying radioactive and hazardous materials
in the soil. Finally, in situ treatment poses a
lower potential risk to workers than traditional
treatments because contaminants are not
brought to the surface. This technology,
however, has not yet been demonstrated at
depths beyond twenty feet.
Technology Performance
A small-scale ISV test at DOE's Hanford Nuclear
Reservation produced the following conclusions:
• Injection of a conductive glass frit and
sodium silicate slurry into the rocky layer
below the crib enhances the downward
penetration of the ISV melt;
• Wood pyrolysis rates calculated from the
small-scale test results indicate that the
increased heat load to the off-gas system
from the wooden timbers in the crib will
raise the off-gas temperature to about 300
degrees Celsius, well within the operating
limits of the off-gas system and hood;
A full-scale field demonstration at Hanford was
also successful:
• The product passed the TCLP and
reduced the risk to workers and the
public;
• Waste volume was reduced by 25
percent;
• ISV can treat 100 tons of soil per day;
• Residual wastes include scrub solution
from off-gas treatment (approximately 0.25
gallons per ton of waste), treated waste is
a delistable glass and crystaline block;
and
• Obsidian-like glass and crystalline product
will not require long term monitoring.
Remediation Costs
Approximately $150 to $350 per ton of soil.
General Site Information
A field demonstration at DOE waste tanks was
conducted at the Hanford Nuclear Reservation,
Washington. A one meter diameter by one
meter tall instrumented underground tank was
melted in September 1990. Hazardous
constituents of the tank, the tank itself and soil
beneath the tank were converted to a 30 ton
block which passes the TCLP leach rate criteria.
A 6000 gallon tank will be vitrified by summer
1991.
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The 116-B-6A CRIB full-scale field demonstration
was conducted at the 100-B Area in Hanford
between 1988 and 1991. The site in the crib
contained approximately 900 mCi of Strontium-
90, 150 mCi of Cesium-137, and a mixture of
other hazardous constituents including
chromium and lead.
Contacts
Sydney S. Koegler
Pacific Northwest Laboratory
P.O. Box 999
Richland, Washington 99352
509/376-0492
FTS: 444-0492
W.F. Bonner
Manager Vitrification Programs
M.S. P7-44 Battelle
P.O. Box 999
Richland, Washington 99252
509/376-5207
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Ill
a
Other Physical Treatment
Membrane Microfiitration
Organic, Inorganic, and Oily Wastes in Ground Water, Wastewater, and Soil
Technology Description
This rnicrofiltration system is designed to remove
solid particles from liquid wastes, forming filter
cakes typically ranging from 40 to 60 percent
solids. The system can be manufactured as an
enclosed unit, requires little or no attention
during operation, is mobile, and can be trailer-
mounted.
This treatment technology is applicable to
hazardous waste suspensions, particularly liquid
heavy metal- and cyanide-bearing wastes (such
as electroplating rinsewaters); ground water
contaminated with heavy metals; landfill
leachate; and process wastewaters containing
uranium. The technology is best suited for
treating wastes with solid concentrations less
than 5,000 parts per million; otherwise, the cake
capacity and handling become limiting factors.
The developers claim the system can treat any.
type of solid, including inorganics, organics, and
oily wastes with a wide variety of particle sizes.
Moreover, because the unit is enclosed, the
system is said to be capable of treating liquid
wastes containing volatile organics.
The DuPont/Oberlin rnicrofiltration system uses
Oberlin's automatic pressure filter combined with
DuPont's special Tyvek filter material (Tyvek T-
980). made of spun-bonded olefin. The filter
material is a thin, durable plastic fabric with tiny
openings (about one ten-millionth of a meter in
diameter) that allow water or other liquids, along
with solid particles smaller than the openings, to
flow through. Solids in the liquid stream that are
too large to pass through the openings
accumulate on the filter, and can be easily
collected for disposal.
The automatic pressure filter has two chambers:
an upper chamber for feeding waste through the
filter, and a lower chamber for collecting the
filtered liquid (filtrate). At the start of a filter
cycle, the upper chamber is lowered to form a
liquid-tight seal against the filter. The waste feed
is then pumped into the upper chamber and
through the filter. Filtered solids accumulate on
the Tyvek surface, forming a filter cake, while
filtrate is collected in the lower chamber. Air is
fed into the upper chamber at about .45 pounds
per square inch, and used to further dry the
cake and remove any liquid remaining in the
upper chamber. When the cake is considered to
be dry, the upper chamber is lifted and the filter
cake is automatically discharged. Clean filter
material is then drawn from a roll into the system
for the next cycle. Both the filter cake and the
filtrate can be collected and treated further prior
to disposal if necessary.
Technology Performance
The DuPont/Oberlin microfiltration system was
recently demonstrated at the Palmerton Zinc
Superfund site in Palmerton, Pennsylvania. The
system was tested for treating a shallow aquifer
contaminated with dissolved heavy metals (such
as cadmium, lead, and zinc). Pilot studies on
ground water at this site have shown that the
microfiltration system can produce a 35 to 45
percent-solids filter cake, and a filtrate with non-
detectable levels of heavy metals.
During this demonstration the DuPont/Oberlin
microfiltration system the results were positive:
• Zinc and total suspended solids removal
efficiencies ranged from 99.75 to 99.99
percent;
• Solids in the filter cake ranged from 30.5
to 47.1 percent;
• Dry filter cake in all test runs passed the
RCRA permit filter liquids test;
• Filtrate met the applicable National
Pollution Discharge Elimination System
standard for zinc, but exceeded the
standard for pH; and
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• A composite filter cake sample passed the
EP Toxicity and TCLP tests for metals.
EPA prepared a Demonstration Bulletin
summarizing the results of the demonstration in
August 1990 and is currently finalizing a
Technology Evaluation Report, Applications
Analysis Report, and video of the demonstration.
General Site Information
This technology was demonstrated over a four-
week period in April and May 1990 at the
Palmerton Zinc Superfund site in Palmerton,
Pennsylvania.
Contacts
EPA Project Manager:
John F. Martin
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7758
FTS: 684-7758
Technology Developer Contact:
Ernest Mayer :
E.I. DuPont de Nemours and Company
Engineering Department L1359
P.O. Box 6090
Newark, Delaware 19714-6090
302/366-3652
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Other Physical Treatment
Precipitation, Microfiltration, and Sludge Dewatering
Heavy Metals, Oil and Grease, Bacteria in Water
Technology Description
This technology is applicable to water containing
heavy metals, pesticides, oil and grease,
bacteria, suspended solids, and constituents that
can be precipitated into particle sizes greater
than 0.1 micron. The system can handle waste
streams containing up to 5% (50,000 ppm)
contaminant, producing a filtrate with less than
1.0 ppm and a semi-dry cake of 40-60%.
Nonvolatile organics and solvents can also be
treated by adding powdered adsorbents. Soils
and sludge can be decontaminated through acid
leaching of the metals followed by precipitation
and microfiltration. Lime sludges from municipal,
industrial, and power plant clarifiers can also be
treated using this process.
In the first step of this process, heavy metals are
chemically precipitated. The precipitates, along
with all particles down to 0.2 - 0.1 micron, are
filtered through a unique fabric crossflow
microfilter (EXXFLOW). The concentrated stream
is then dewatered in an automatic tubular filter
press of the same fabric material (EXXPRESS).
EXXPRESS filter cakes of up to 60 percent solids
(weight per weight) are possible.
Microfiltration involves a proprietary woven
polyester array of tubes. Waste effluent is
pumped into the tubes and forms a dynamic
membrane, which produces a high quality filtrate
removing all particle sizes below 0.2 - 0.1 micron.
The membrane is continually cleaned by the flow
velocity, thereby preventing flux reduction.
Metals are removed via precipitation by adjusting
the pH in the EXXFLOW feed tank. The metal
hydroxides or oxides form the dynamic
membrane with any other suspended solids.
The concentrated stream will contain up to 5
percent solids for discharge to the EXXPRESS.
Water recoveries are above 90 percent in most
cases.
Other constituent removals are possible, using
seeded slurry methods in EXXFLOW: hardness
can be removed using lime; oil and grease can
be removed using adsorbents; and nonvolatile
organics and solvents can be removed using
seeded, powdered activated carbon or
powdered ion exchange adsorbents. The
concentrate stream produced by EXXFLOW
enters EXXPRESS with the discharge valve
closed. A semi-dry cake up to 1/4 inch thick is
formed on the inside of the tubular cloth. When
the discharge valve is opened, rollers on the
outside of the tubes move to form a venturi
within the tube. The venturi creates an area of
high velocity within the tubes, which aggressively
cleans the cloth and discharges the cake in chip
form onto a wedge wire screen. The discharge
water is recycled back to the feed tank. In cases
where the solids in the raw feed water are
extremely high, EXXPRESS can be used first,
with EXXFLOW acting as a final polish for the
product water.
In special circumstances, chelating agents can
also be used to remove a particular metal. The
leached slurry containing the solubilized metals
is separated by an automatic cake discharge
tubular filter press. The resulting filtrate is
chemically treated to precipitate the heavy
metals in hydroxide form.
Residual organic contamination in this precipitate
can be removed with activated carbon. Heavy
metals in the precipitate are separated and
concentrated by microfiltration, using an
innovative and flexible woven textile material that
can separate particles as small as 0.1 microns.
The process is capable of handling widely
varying incoming solids concentrations.
The demonstration unit is transportable and is
skid-mounted. The unit is designed to process
approximately 30 pounds of solids per hour.
Technology Performance
Bench-scale tests of this technology have been
conducted. The first application was scheduled
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in late 1990 on acid mine drainage at the Iron
Mountain Mine Superfund Site in Redding,
California.
Contacts
EPA Project Manager:
S. Jackson Hubbard
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH 45268
513-569-7507
FTS: 684-7507
Technology Developer Contact:
Ray Groves
EPOC Water, Inc.
3065 Sunnyside, #101
Fresno, CA 93727
209-291-8144
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Other Physical Treatment
Rotary Air Stripping
Volatile Contaminants in Ground Water
Technology Description
A rotary air stripper is a vapor and liquid
contactor which uses centrifugal force to push
contaminated water through packing material
while air is pushed counter current to the flow of
water. The centrifugal force results in a high
mass transfer rate of the contaminant from the
water to the air. The main advantage of this
rotary air stripper is the reduction of the height of
the stripping equipment. Large, tall towers are
inherent in conventional packed column air
stripping.
Technology Performance
In the first tests with a rotary air stripper
conducted at the Traverse City Coast Guard
Station, a 100-gpm rotary air stripper showed
removal of the contaminant as a function of the
liquid to gas ratio and the speed (rpm) of the
spinning rotor. The data showed that the
removal efficiency increased with an increase in
the gas-to-liquid ratio up to a value of about 30
(vol/vol). Above this value, minimal increases in
removal efficiencies were realized with increased
gas-to-liquid ratios. A similar phenomenon was
observed when assessing the effect bf the rotor
speed on the removal efficiency. Increasing the
rotation above approximately 600 rpm produced
minimal changes in the removal efficiency. In all
the tests, high removal efficiencies (greater than
99 percent) were achieved with the highly volatile
contaminants, while relatively low removal
efficiencies were observed for the less volatile
contaminants. In these tests, only one size and
type of packed rotor was used, and only influent
and effluent data could be taken.
In the second tests, conducted at Elgin AFB,
three different sizes of rotors and two different
types of packing materials were used, along with
an internal sampling mechanism.. Using the
different packed rotors, data was obtained to
develop and compare equations for predicting
the mass transfer pressure drops, and power
consumption of the rotary air stripper. The
equations can be used to design the size,
rotating speed, air-to-water ratios, and energy
necessary for a rotary air stripper to meet site
specific performance requirements.
The only limitation noted was that plugging
occurred due to mineral deposits in the rotors at
one site where the ground water has a very high
iron content (approximately 9 ppm).
General Site Information
Field tests have been conducted at Elgin AFB
and at the U.S. Coast Guard Station at Traverse
City, Michigan.
Contact
Capt. Edward G. Marchard
AFESC
Tyndall AFB, Florida 32403-6001
(904) 283-2942
Federal Remediation Technologies Roundtable
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INFLUENT AIR
EFFLUENT AIR
t
ROTATING PACKING
EFFLUENT WATER
INFLUENT WATER
X-VALVE
-*- DIRECTION OP
106
Federal Remediation Technologies Roundtable
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Other Physical Treatment
Treatment with Ultra Violet, Hydrogen Peroxide, and Ozone
Trichloroethene in Ground Water
Technology Description
This oxidation process uses ozone, ultraviolet
radiation, and hydrogen peroxide for the
treatment of ground water contaminated with
trichloroethene (TCE).
Technology Performance
Results from the full-scale, advanced oxidation
process tested at the DOE Kansas City plant
were mostly inconclusive:
• The plant is effective in the destruction of
individual volatile organic compounds but
seems to reach a plateau for gross
parameters such as total organic carbon
and total chlorinated hydrocarbons;
• The plant has been out of service for
maintenance and repair approximately 30
percent of the time;
• The flow rate has averaged approximately
15 percent of the design flow rate, so the
determination of costs has been
inconclusive; and
An evaluation of the true plant capacity
indicates that it can accommodate twice
the rated flow rate.
Remediation Costs
Actual costs are not available; however, the
costs are competitive with other processes.
General Site Information
A full-scale, advanced oxidation process was
tested at the DOE Kansas City Plant.
Contacts
Sidney B. Garland II
Oak Ridge National Laboratory
P.O. Box 2008
Oak Ridge, Tennessee 37831-6317
615/574-8581 or (FTS) 624-8518
Federal Remediation Technologies Roundtable
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Other Physical Treatment
Ultrafiltration
Toxic Metals in Ground Water
Technology Description
This combination chemical-ultrafiltration
treatment process is intended for use on toxic
metals in ground water. Ultrafiltration has thus
far been applied exclusively to the removal of
colloidal solids and fairly large molecules. This
technology may potentially be used to separate
toxic heavy metals such as cadmium, chromium,
lead, mercury, selenium, silver and barium (as an
in-situ formed precipitate) from ground water
generated at Superfund sites. Other inorganic
and organic materials present as suspended and
colloidal solids may also be removed.
Ultrafiltration can be applied in combination with
chemical treatment to selectively remove
dissolved metal ions from dilute aqueous
solutions. A high molecular weight chelating
agent is added to the incoming waste solutions
to form macromolecular complexes. The metal
ions can then be easily removed.
Usually, each chelating polymer is marked for
one metal or for a group of similar cations.
Once the polymer is added, the solution is
processed through an Ultrafiltration membrane
system that collects the macromolecular
complexes (retentate) on the membrane, but
allows uncomplexed ions such as sodium,
potassium, calcium, chloride, sulfate, and nitrate,
to pass through as filtered water (permeate).
The filtered water can be recycled or discharged
depending upon the metal removal
requirements. A removal efficiency approaching
100 percent can be achieved for metal ions in
ground water.
The retentate, which constitutes about 5 to 20
percent of the feed volume, contains the
separated heavy metal ions and must be treated
further. The retentate is either solidified to
prevent the release of toxic metals back to the
environment or recycled through the treatment
process for further volume reduction.
Because many simple and non-toxic ions are
allowed to pass through the membrane as per-
meate, they are not concentrated together with
the metal ions. The retentate will have a smaller
volume and the solidified product will be more
resistant to leaching, due to its smaller salt
content and the presence of chem-icals that
retard the migration of toxic metals.
Technology Performance
Results of bench-scale tests showed the
following removal rates: cadmium and mercury,
up to 99 percent; lead, 90 percent; and arsenic,
10 to 35 percent. Arsenic is an anionic species,
and is not as effectively removed as the other
metals. Separation of non-arsenic metals was
found to be more efficient in alkaline conditions.
This research also indicated that Ultrafiltration,
unlike conventional precipitation technologies,
does not require the production of large particles
and, thus, may be more applicable to feed
streams with high variability in metals
concentration.
Contacts
EPA Project Manager:
John F. Martin
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
(513) 569-7758
FTS 684-7758
Technology Developer Contact:
Leo P. Buckley
Atomic Energy of Canada Ltd.
Waste Management Technology Division
Chalk River Nuclear Labs
Chalk River, Ontario KOJ IJO
Canada
(613)584-3311
108
Federal Remediation Technologies Roundtable
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Other Physical Treatment
Ultraviolet Ftadiation / Oxidation
Toxic Organic Compounds in Water
Technology Description
This ultraviolet (UV) radiation/oxidation process
uses UV radiation, ozone (O3), and hydrogen
peroxide (H2O2) to destroy toxic organic
compounds, particularly chlorinated
hydrocarbons in water. Contaminated ground
water, industrial wastewaters and leachates
containing halogenated solvents, phenol,
pentachlorophenol, pesticides, polychlorinated
biphenyls (PCBs), and other organic compounds
are suitable for this treatment process. The
process oxidizes compounds that are toxic or
refractory (resistant to biological oxidation) in
concentrations of parts per million (ppm) or parts
per billion (ppb).
The Ultrox system consists of a reactor module,
an air compressor/ozone generator module, and
a hydrogen peroxide feed system. It is skid-
mounted and portable, and permits on-site
treatment of a wide variety of liquid wastes, such
as industrial wastewater, ground water, and
leachate. The expected wastewater flow rate and
the necessary hydraulic retention time to treat
the contaminated water determine the reactor
size. Pilot-scale studies determine the
approximate UV intensity, and ozone and
hydrogen peroxide doses.
Influent to the reactor is simultaneously exposed
to UV radiation, ozone, and hydrogen peroxide
to oxidize the organic compounds. Off-gas from
the reactor passes through an ozone destruction
(Decompozon) unit, which reduces ozone levels
before air venting. The Decompozon unit also
destroys gaseous volatile organic compounds
(VOCs) stripped off in the reactor. Effluent from
the reactor are tested and analyzed before
disposal.
Technology Performance
The test program was designed to evaluate the
performance of the Ultrox System for several
combinations of five operating parameters:
(1) influent pH, (2) retention time, (3) ozone
dose, (4) hydrogen peroxide dose, and (5) UV
radiation intensity. Contaminated ground water
treated by the Ultrox system at a San Jose,
California hazardous waste site met regulatory
standards at the following operating conditions:
• Retention time - 40 minutes;
• Influent pH - 7.2 (unadjusted);
• O3 dose -110 mg/L;
• H2O2 dose -13 mg/L; and
• UV lamps - all 24 operating at 64 watts
each.
Out of 44 VOC samples, three were chosen to
be used as indicator parameters. The VOC
removal efficiencies at these conditions are
presented in Table 1.
Removal efficiencies for trichloroethylene (TCE)
were about 99 percent. Removal efficiencies for
1,1-DCA and 1,1,1-TCA were about 58 percent
and 85 percent, respectively. Removal
efficiencies for total VOCs were about 90
percent. For some compounds, removal from
the water phase was due to .both chemical
oxidation and stripping. Stripping accounted for
12 to 75 percent of the total removal for 1,1,1-
TCA and 5 to 44 percent for 1,1 -DCA. Stripping
was less than 10 percent for TCE and vinyl
chloride, and was negligible for other VOCs
present.
The Decompozon unit reduced ozone to less
than 0.1 ppm (OSHAstandards), with efficiencies
greater than 99.99 percent. VOCs present in the
air within the treatment system, at approximately
0.1 to 0.5 ppm, were not detected after passing
through the Decompozon unit. Very low TOG
removal was found, implying that partial
oxidation of organics occurred without complete
conversion to CO2 and H2O. The average
electrical energy consumption was about 11
kW/hour of operation.
Federal Remediation Technologies Roundtable
109
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General Site Information
EPA completed a field-scale demonstration in
March 1989 at a hazardous waste site in San
Jose, California. EPA published the Technology
Evaluation Report in January 1990 (EPA/540/A5-
89/012). EPA published the Applications
Analysis Report in December 1990.
Contacts
EPA Project Manager:
Norma Lewis
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive >
Cincinnati, Ohio 45268
513/569-7665
FTS: 684-7665
Technology Developer Contact:
David B. Fletcher
Ultrox International
2435 South Anne Street
Santa Ana, California 92704
714/545-5557
Run 9
TCE
1,1-DCA
1,1,1-TCA
Total VOCs
Run 12
TCE
1,1-DCA
1,1,1-TCA
Total VOCs
Run 13
TCE
1,1-DCA
1,1,1-TCA
Total VOCs
PERFORMANCE
Mean Influent
fao/U
65
11
4.3
170
52
11
3.3
150
49
10
3.2
120
TABLE 1
DATA FOR REPRODUCIBLE RUNS
Mean Effluent
fcra/U
1.2
5.3
0.75
16
0.55
3.8
0.43
12
0.63
4.2
0.49
20
Percent Removal
98
52
83
91
99
65
87
92
99
58
85
83
110
Federal Remediation Technologies Roundtable
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Other Physical Treatment
Wetlands-Based Treatment
Metals in Influent Waters
Technology Description
This constructed wetlands-based treatment
technology uses natural geochemical and
biological processes inherent in a man-made
wetland ecosystem to accumulate and remove
metals from influent waters. The wetlands-based
treatment process is suitable for acid mine
drainage from metal or coal mining activities.
These wastes typically contain high metals
concentrations and are acidic in nature.
Wetlands treatment has been applied with some
success to wastewater in the eastern regions of
the United States. The process may have to be
adjusted to account for differences in geology,
terrain, trace metal composition, and climate in
the metal mining regions of the western United
States. The treatment system incorporates
principal ecosystem components found in
wetlands, including organic soils, microbial
fauna, algae, and vascular plants.
Influent waters, which contain high metal
concentrations and have low pH levels, flow
through the aerobic and anaerobic zones of the
wetland ecosystem. Metals are removed by
filtration, ion exchange, adsorption, absorption,
and precipitation through geochemical and
microbial oxidation and reduction. In filtration,
metal flocculates and metals that are adsorbed
onto fine sediment particles settle in quiescent
ponds, or are filtered out as the water percolates
through the soil or the plant canopy. Ion
exchange occurs as metals in the water come
into contact with humic or other organic
substances in the soil medium.
Oxidation/reduction reactions that occur in the
aerobic/anaerobic zones, respectively, play a
major role in removing metals as hydroxides and
sulfides.
Technology Performance
EPA approved second-year funding for the
project under the Emerging Technologies
Program. A pilot-scale system has been built to
assess the effectiveness of constructed wetlands
in treating the effluent from the Big Five Tunnel
near Idaho Springs, Colorado. After two years of
operation, the pilot study is yielding optimum
results:
pH raised from 2.9 to 6.5;
Copper reduced to below detection limit;
Zinc reduced by 97 percent;
Iron reduced by 80 percent;
Aluminum, Cadmium, and Lead decreased
90-100 percent;
• Cobalt and Nickel decreased 50 percent;
and
• Biotoxicity to fathead minnows and
Ceriodaphnia reduced by factors of 4 to
20.
General Site Information
EPA has selected this technology for the SITE
Demonstration Program. A full-scale
demonstration site has not yet been selected,
but candidate sites include mineral mining
facilities.
Contacts
EPA Project Manager:
Edward R. Bates
U.S. EPA
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
513/569-7774
FTS: 684-7774
Technology Developer Contact:
Thomas Wildeman
Colorado School of Mines
Golden, Colorado 80401
303/273-3642
Federal Remediation Technologies Roundtable
111
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INNOVATIVE REMEDIAL TECHNOLOGY
INFORMATION REQUEST FORM
INSTRUCTIONS FOR SUBMITTING AN ABSTRACT
The following is the suggested format for submitting a remedial technology abstract for
inclusion in the Synopses of Federal Demonstration Projects for Innovative Hazardous
Waste Treatment Technologies. The format has been divided into five sections, each
designed to gather specific information for the abstract. These five sections are:
• Technology Description;
• Technology Performance;
• Remediation Costs;
• General Site Information; and
• Contacts.
Although a form has been provided for your convenience, you may submit abstract
information without use of this form, or you may attach additional information to this form,
as necessary. If possible, this information should be presented in the same order as it
appears in this example. It is understood that many abstracts will contain only partial
information, as the projects are still being tested; however, please submit as much
information as possible, as this will assist others in better understanding the innovative
treatment technology.
Abstract information, comments, and questions relating to this project should be directed
to:
Daniel M. Powell
Technology (novation Office
U.S. Environmental Protection Agency
401 M Street, S.W., OS-110
Washington, D.C. 20460
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INNOVATIVE REMEDIAL TECHNOLOGY
INFORMATION REQUEST FORM
1. TECHNOLOGY DESCRIPTION
Type of Technology and Exact Technology Name (e.g., Bioremediation: Aerobic Biodegradation of
Trichloroethylene):
Waste Description (e.g., RGB's in sludge):
Media Contaminated (e.g., groundwater, soil, surface water):
Targeted Contaminants and Concentrations (e.g., RGB's at 500 ppm):
Description of Treatment Process:
Description of Preliminary or Secondary Treatment, If Any:
Summary of Monitoring Results (e.g., air emissions, waste water discharge):
Limitations of Technology (e.g., weather, soil type, depth of water table):
* * Page 2 * *
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2. TECHNOLOGY PERFORMANCE
Overall Attainment of Clean-Up Goals (e.g., residual contamination):
Summary of Data Used to Evaluate Technology Effectiveness:
Treatment Capacity (e.g., gallons per day, tons per day):
Types and Amounts of Residual Wastes (e.g., ash, steam, wastewater):
Ultimate Disposal Options (e.g., landfilling of ash):
Malfunctions and Disruptions Encountered:
Interfering Compounds:
Description and Length of Future Maintenance and Monitoring Required:
Additional Comments:
* * Page 3 * *
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3. REMEDIATION COSTS
Total cost of Remediation Project, Not Including Site Investigations:
Cost of Remediaiton Project per Unit of Waste,
Not Including Site Investigations (e.g., dollars per ton):
Design Costs:
Time Required for Design:
Site Preparation:
Equipment Costs:
Start-up and Fixed Costs (e.g., transportation, insurance, shakedown, training):
Labor Costs (e.g., salaries and living expenses):
Consumables and Supplies (e.g., chemicals, cement):
Utilities (e.g., fuel, electricity):
Effluent Treatment and Disposal:
Residuals/waste shipping and handling:
Analytical Services:
Maintenance and Modification:
Demobilization:
Projected Costs of Future Maintenance and Monitoring per Year:
Estimated Time Required for Operation and Maintenance:
Page 4 * *
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4. GENERAL SITE INFORMATION
Site Name:
Site Location:
Time Period Covered by the Project:
Scale of Project (i.e., treatability study, bench scale, pilot test, field demonstration or full-scale
remediation):
Site Characterization Data (to the extent that it affects the treatment process):
Volume of Area Contaminated:
Facility's Current and Previous Uses:
Facility Contact:
Remedial Action Contractor:
Contractor Contact:
Other Contacts:
* * Page 5 *
U.S. GOVERNMENT PUNTING OmCE:1S01-S4B-ie7/S5(>31
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Suggestions
If you know of additional projects that should be included in this compendium, or if you are often in need
of this type of information and don't know how to find it, please make a note on this page. This is a self-
addressed mailer - just add postage, and drop it in the mail.
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fold here
Daniel Powell
Environmental Protection Specialist
Technology Innovation Office
U.S. Environmental Protection Agency
401 M Street, SW, OS-110
Washington, D.C. 20460
fold here
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