540291016
        United States
        Environmental Protection
        Agency
Office of Solid Waste and
Emergency Response
Washington, DC 20460
EPA/540/2-91/016
September 1991
        Superfund
wEPA  Abstract Proceedings:

        Third Forum on
        Innovative Hazardous
        Waste Treatment
        Technologies:
        Domestic and
        International

        Dallas,  Texas
        June 11-13, 1991

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                                   September 1991
                                   EPA/540/2-91/016
    ABSTRACT PROCEEDINGS
THIRD FORUM ON INNOVATIVE HAZARDOUS WASTE
         TREATMENT TECHNOLOGIES:
        DOMESTIC AND INTERNATIONAL
                  Dallas, TX
               June 11-13,1991
         TECHNOLOGY INNOVATION OFFICE
   OFFICE OF SOLID WASTE AND EMERGENCY RESPONSE
      U.S. ENVIRONMENTAL PROTECTION AGENCY
             WASHINGTON, DC 20460
                    AND
      RISK REDUCTION ENGINEERING LABORATORY
       OFFICE OF RESEARCH AND DEVELOPMENT
      U.S. ENVIRONMENTAL PROTECTION AGENCY
              CINCINNATI, OH 45268
                               Printed on Recycled Paper

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                     ACKNOWLEDGMENTS
The Third Forum on Innovative Hazardous Waste Treatment Technologies:
Domestic and International was sponsored by the U.S. Environmental Protection
Agency's (EPA's) Technology Innovation Office - Walter Kovalick.i Director.
The Forum programs and activities were planned by a committee consisting of
the following members:
Ed Barth,  U.S. EPA, Center for Environmental Research Information (CERI),
Cincinnati, OH
Thomas De Kay, U.S. EPA, Technology Innovation Office (TIO), Washington, DC
Scott  Fredericks, U.S.  EPA, Office of Emergency and Remedial Response
(OERR), Washington, DC
Deborah Griswold, U.S. EPA, Region VI, Dallas, TX
Stephen James, U.S. EPA, Risk Reduction Engineering Laboratory (RREL),
Cincinnati, OH
Margaret Kelly, U.S. EPA, TIO, Washington, DC
John Kingscott, U.S. EPA, TIO, Washington, DC
Walter Kovalick, U.S. EPA, TIO, Washington, DC
Lisa Kulujian, JACA Corporation, Fort Washington, PA
Robert Olexsey, U.S. EPA, RREL, Cincinnati, OH
Richard  Steimle, U.S. EPA, TIO, Washington, DC
Thomas Voltaggio, U.S. EPA, Region III, Philadelphia, PA
The conference was coordinated by JACA Corporation, Fort Washington, PA
19034, under subcontract to SAIC, Cincinnati, OH 45203.

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                            Table of Contents
Biological Groundwater And Soil Vapor Treatment	1
Enhanced Composting For Cold-climate Biodegradation Of
Organic Contamination In Soil	y.	2
Extraction Of Mercury From Groundwater Using Immobilized Algae	3
Case Studies: Solidification/Stabilization	4
Wastech's Solidification/Stabilization Process	6
SITE Technology Demonstration Summary— SITE Program Demonstration
Of A Trial Excavation At The McColl Superfund Site	6
On Site Soil Vapor Extraction (SVE) Of Contaminated Soil	8
Mobile Extraction Technology For On-site Soil Decontamination:
Contex System	9
Zero Air Emissions Groundwater And Soil Remediation Using The
AWD Integrated System: A Site Project In Operation For 3-1/2 Years	10
Demonstration Of Debris Washing Technology	11
Developments And Operating Experience In Soilcleaning: A Progress
Report On The Developments In Cleaning Soils With Chlorinated
Hydrocarbons, And The Development Of A Wet Cleaning Method For
Contaminated Sand	12
Experience Acquired With The Oecotec High - Pressure Soil
Washing Plant 2000 In Cleaning Contaminated Soil	14
Extraction And Drying Of Superfund Wastes With The
Carver-Greenfield Process®	15
B.E.S.T. Solvent Extraction Treatment Of Toxic Sludge, Sediment And Soil	16
Purification Of Landfill Leachate Based On Reverse Osmosis And
Rochem Disc Tube""  Module DT	17
Innovative Concept For Evaluation Of In-srtu Treatment Of Contaminated
Soil And Groundwater	18
Incineration Plant For Toxic Wastes Of The Federal German Armed
Forces Defense Science Agency For NBC-Protection	19
In-situ Groundwater Remediation Of Strippable Contaminants By Vacuum
Vaporizer Wells (UVB): Operation Of The Well And Report About Cleaned
Industrial Sites	20
In Situ Groundwater Remediation Of Strippable Contaminants By
Vacuum Vaporizer Wells (UVB): Description Of The Circulation System
By Numerical Results	21

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A Combined Chemical Treatment And Ultrafiltration Membrane Process For
The Selective Removal Of Toxic Metals from Groundwater And Waste Water	49
B&W Cyclone Furnace For Waste Vitrification	50
Methanotrophic Bioreactor To Cooxidize Halogenated Aliphatic Hydrocarbons
SuchAsTCE	51
Biogenesis8"1 Soil Cleaning Process: Technology Summary	52
X*traxtm - Transportable Thermal Separator For Organic Contaminated Solids	54
Alternating Current Electrocoagulation ForSuperfund Site Remediation	55
Laser Induced Photochemical Oxidative Destruction Of Toxic Organics In
Aqueous Streams (LIPOD)	56
In-situ Bioremediation Of Deep Contaminated Sites Utilizing The I-SF Dual
Auger System	57
 Two-stage Fluidized-bed/cyclonic Agglomerating Incinerator	58
Pilot Plant Evaluation Of Photolysis/Biodegradation Treatment Of PCB
And PCDD/PCDF Contaminated Soils	59
Pilot Plant Demonstration Of Batch Steam Distillation/Metal Extraction
Treatment Of Contaminated Superfund Soils	.61
The Air-sparged Hydrocyclone: A Device For Recovery Of Metal Values
From Mining Wastes	62
Technical Description  Of The DAVE System	63
Sarex Chemical Fixation Process (SAREX CFP)	64
Chemical-physical Filter For Heavy Metals And Radionucllde Pollutants	65
Technology Support Center: The Robert S. Kerr Environmental
Research Laboratory	66
Subsurface Remediation Technology Database: A Superfund Technical
Assistance Tool	68
Description Of The Ultrox D-TOX Process	69
Treatment Of Nitroaromatic Residues In Soil: a Novel Anaerobic Process	70
High-energy Electrons For The Removal Of Hazardous Organic Compounds	71
A Transversal Flow Pervaporation System For The Removal And
Concentration Of Volatile Organic Compounds	72
Pact® System And Wet Air Oxidation Applications For Site Clean-up And
Treatment Of Hazardous Wastes And Wastewaters	73

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Chlorinated benzene and HCH were also removed, although beta and epsilon
HCH seemed not to be biologically degradable. Loadings of up to 2.2g/m /h
were used and still good results were attained.  Usage of the RBC resulted in a
cost reduction  of about 30-40 percent.  Both contaminated soil vapor and
groundwater were treated with good results. Stripping of volatile compounds
was less than 1 percent. Removal efficiencies of up to 99 percent were obtained.
Loadings of 22 g/m3/d were used. The UAC and Biopur are both very simple
processes and are easy to build. The costs to build and operate this system are
small and therefore the process will be competitive to physical/chemical treat-
ment systems.
ENHANCED COMPOSTING FOR COLD-CLIMATE
BIODEGRADATION OF ORGANIC CONTAMINATION IN
SOIL

James D. Berg
Aquateam - Norwegian Water Technology Centre A/S
P.O. Box 6326 Etterstad
0604 Oslo 6
Norway
Tel: (472) 679310
Fax: (472) 672012

Trinetggen
Terrateam - Norwegian Environmental Technology Centre A/S
P.O. Box 344
8601 Mo i Rana
Norway

Bioremediation of soils contaminated with hazardous wastes is becoming a
preferred technology because of Its simplicity, lack of residuals requiring special
handling, and low cost relative to traditional alternatives. Bioremediation was
evaluated for a coke works site in northern Norway near the Arctic Circle,
characterized in 1989 as having significant contamination by pdycyclic aromatic
hydrocarbons (PAHs).  About 20,000 tons of soil containing PAHs (ca. 500
mg/kg) were excavated.  Groundwater at the site contained ca. 2-3 mg/l and
0.4-1.6 mg/l,naphthalene and benzol. A pilot study was conducted in 1990, in
which 1,000m3 of soil were treated in an enhanced composting system.  Com-
posting was chosen over landfarming or slurry reactors because of:  low capital
and operating costs; on-site capability (lowarea requirement); minimal develop-
ment requirements; and capability for cold-climate, year-round operation.

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metal ions (over calcium and magnesium), functions well with solutions with high
dissolved solid content, and is Capable of reducing metal Ions to ppb levels.
Once bound to the AlgaSORB®, metal ions can be stripped in, a highly con-
centrated form.

This new technology has been demonstrated to be an effective method for
removing toxic metals from groundwater. Metal concentrations can be reduced
to very low ppb levels. An important characteristic of the binding material is that
high concentrations of common ions such as calcium, magnesium, sodium,
potassium chloride and sulfate do not interfere with the heavy metal binding.
Waters containing a total dissolved solids content of several thousand and a
hardness of several hundred ppm can be successfully treated to remove and
recover heavy metals.

The process has been demonstrated to be effective for mercury removal from
contaminated groundwater by benchtop and pilot treatability studies through
EPA's SITE Emerging Technology Program.  In addition the process has been
shown to be effective for mercury and uranium removal from contaminated
groundwater  from  DOE sites at Hanford, Oak Ridge, and Savannah River
through DOE's Applied Research and Development Program.
 CASE STUDIES: SOLIDIFICATION/ STABILIZATION

 Steve Pegler
 Silicate Technology Corporation
 7655 E. Gelding Drive - Suite B-2
 Scottsdale, Arizona 85260
 USA
 Tel: (602)948-7100

 This abstract summarizes three case studies of use and performance of Silicate
 Technology Corporation (STC)solidification/stabilization processes:  a
 demonstration project for a coal gasification/car shredder facility, STC's EPA
 Superfund Innovative Technology Evaluation (SITE) demonstration project, and
 a full scale remediation project at a battery recycling plant. STC technologies
 have been used in the full scale remediation of over 400,000 cubic yards of
 contaminated soils and sludges in numerous projects throughout the country.


 STC performed an extensive pilot scale on-site stabilization study  in October
 1990. This site contained three major types of contamination from a coal
 gasification plant that used to exist on the site and an auto shredder salvage

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success rate of 98.7%.  The remaining 1.3% of the treated materials were
crushed and successfully retreated resulting in an effective 100% successful
treatment of all contaminated soils. STC professionals assisted the client's
engineers in the development of site work plans and in regulatory approvals.
WASTECH: SOLIDIFICATION/STABILIZATION PROCESS

E. Benjamin Peacock
WASTECH, INC.
114TulsaRd.
P.O. Box 4638
Oak Ridge, TN 37831-4638
USA
Tel: (615) 483-6515

WASTECH, INC. entered the  EPA SITE Program to illustrate the overall effec-
tiveness of its processes in dealing with organic contaminants. By applying the
results of a dedicated research and  development program,  WASTECH
demonstrates a high degree of success in treating volatile organics, semivolatile
organics, and heavier organic mediums found in sludges, soils, and debris as
well as actual raw waste streams. This treatment process proves effective at the
bench, pilot, and full scale.

This paper provided a brief summary of WASTECH's participation in the SITE
Program.  All analytical data presented were obtained by independent testing
laboratories for validation.
SITE TECHNOLOGY DEMONSTRATION SUMMARY- SITE
PROGRAM DEMONSTRATION OF A TRIAL
EXCAVATION AT THE MCCOLL SUPERFUND SITE

John Blevins
Region IX
U.S. Environmental Protection Agency
75 Hawthorne Ave.
San Francisco, CA 94105
USA
Tel: (415)744-1796

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ON SITE SOIL VAPOR EXTRACTION (SVE) OF
CONTAMINATED SOIL
                                                   i    I
F. Spuy, S. Coffa, C.Pyls, and L Urings
TAUW Infra Consult B.V.
P.O. Box 479
7400 Al Deventer
The Netherlands
Tel: 31 5700 99270
Fax: 31 5700 99666

The extent of soil contamination is enormous in the industrialized countries and
the overall costs of remediation  are extremely high.  Excavation of the con-
taminated soil Is a very effective method of removing pollution.  Nevertheless,
excavation can sometimes be difficult or even Impossible. Although there is a
lot of experience in the USA and Germany, SVE can be considered as a new
remedial technology.  However, good insight into the performance of SVE can
give more possibilities for the  application of the system.  In this paper three
applications of SVE are presented: first, an in situ SVE of a site contaminated
with toluene; second,  an air-based in situ bioreclamation of a site contaminated
with gasoline; third, an on-site application of SVE at a site contaminated with
 perchloroethylene.

To select the most suitable remedial technique for a specific site it is necessary
to calculate the costs. In order to estimate the duration of the SVE a relatively
simple spread sheet model has been developed.

At Site 1, a  former paint factory, toluene contamination was caused by the
spillage of solvents. Concentrations up to 2000 mg/kg were found. The remedial
action techniques considered  were excavation, soil flushing,  and SVE.  For
financial  and practical reasons SVE was considered the best method.  After 6
months of operation the toluene concentration in the soil dropped to ± 1 mg/kg.
The withdrawn concentration in  the soil vapor dropped from 8 gr/ma to ±50
mg/ms; the air flow was 1 SOma/h. A tracer experiment gave a good insight into
the geohydrological situation.

At site 2, a petrol station, an SVE extraction system was placed.  The con-
taminated area was situated under a highway and soil was heavily contaminated
with gasoline (11-18g/kg).  The withdrawn soH vapor and groundwater were
treated together in a biological treatment system developed  by TAUW Infra
Consult B.V (a patent is pending).  Within one year approximately 2700 kg of
gasoline was removed by means of the SVE  system.  The biological removal
rate was approximately 7 mg C/kg/day. The treatment efficiency of the new
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A documentation program has demonstrated the plant's decontamination ef-
ficiency for a number of soil types from Denmark, West Germany, and Norway,
and for very different contamination sources.

The successful tests have included soil contamination ranging from solvents
over oil products to heavy tar fractions. These trials prove that the plant can be
used to combat very concentrated  pollution and that the process can meet the
strictest decontamination requirements.

Concurrently with technical tests, the authorities' approval and comprehensive
safety analyses,  including the fire and emission  risks, have taken place as
documentation.
ZERO AIR EMISSIONS GROUNDWATER AND SOIL
REMEDIATION USING THE AWD INTEGRATED SYSTEM:
A SITE PROJECT IN OPERATION FOR 3-1/2 YEARS

Robert G. Hornsby
AWD Technologies, inc.
400 West Sam Houston Parkway South
Houston, TX 77042
USA
Tel: (713) 978-2960

The Lockheed Aeronautical Systems Company (LASC) was issued a cleanup
and abatement order by the Los Angeles Regional Quality Control Board based
on data obtained in late 1987. The soil and the groundwaterwere contaminated
with trichloroethylene (TCE) and perchloroethylene (PCE). The order required
soil cleanup to start August 1, 1988, and groundwater remediation to begin
September 15,1988.

AWD Technologies was selected on February 1, 1988, to design, install and
operate a remediation system. AWD used its fast track project techniques to
complete the $4 million project in seven and one-half months,  meeting the
mandated deadline. More importantly, the system developed by AWD and later
patented, provided the following benefits:

    Cost:           One-third of conventional technology cost
    Environment:     No air emissions
    Permitting:       Obtained in three weeks
    Image:          Positive television and newspaper coverage
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has been demonstrated on both bench-scale and pilot-scale systems. The DWS
entails the application of an aqueous solution during a high-pressure spray cycle
followed by a turbulent wash cycle. The aqueous cleaning solution is recovered
and reconditioned for reuse concurrently with the debris-cleaning process,
which minimizes the quantity of process water required to clean the debris.

This paper presented the results obtained during the second field demonstration
of the DWS, which was conducted at a pesticide-contaminated site in Chick-
amauga, Georgia. The data presented indicated the effectiveness of the system
for the removal of pesticide and herbicide from the surfaces of metallic debris,
as well as the efficiency of the closed-loop solution- reconditioning system that
is built  into the DWS. In  addition, this paper also addressed the conceptual
design of a full-scale debris washing system.
DEVELOPMENTS AND OPERATING EXPERIENCE IN
SOU-CLEANING, A PROGRESS REPORT ON THE
DEVELOPMENTS IN CLEANING SOILS WITH
CHLORINATED HYDROCARBONS, AND THE
DEVELOPMENT OF A WET CLEANING METHOD FOR
CONTAMINATED SAND

H.J. van Hasselt and A. Costerus
NBM Bodemsanering B.V.
P.O. Box 16032
2500 BA, The Hague
The Netherlands
Tel: 31 703814331
Fax: 31 703834013

NBM Bodemsanering B.V., subsidiary of NBM Amstelland N.V., the second
building and construction group In The Netherlands, has developed an indirect
heated thermal treatment system and has become one of the leading firms in
The Netherlands in the cleaning of soil and the execution of projects for soil
pollution.

Soil pollution comprises a broad spectrum of problems. In developing a soil
cleaning process it is necessary to define areas of interest. As a first area of
interest, NBM elected to clean soil containing pollutants which are hard to break
down. In the first phase, NBM concentrated on cyanide, aromatic hydrocarbons,
and oily-type pollutants. NBM  developed an indirect heated thermal system
using a  dryer and a rotary tube-furnace. The development of the system was
presented at last year's conference.
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EXPERIENCE ACQUIRED WITH THE OECOTEC HIGH -
PRESSURE SOIL WASHING PLANT 2000 IN CLEANING
CONTAMINATED SOIL

Winfried Brull and Michael Mackeprang
Klockner Oecotec
Neudorfer Strasse 3-5
4100 Duisburg
Federal Republic of Germany
Tel: 02 03 18-1 Centrale
Fax: 49 203 33 1917

As you are aware, soil exchange has been the most commonly used form of
land reclamation up to now.

This soil exchange does not solve the problem but only relocates it. Moreover,
this is becoming increasingly difficult,  as landfill space is becoming more and
more scarce, the fees for depositing at the landfill sites are  increasing cor-
respondingly and new administrative regulations for transporting and depositing
contaminated substances have been issued. There is, therefore, a demand for
an innovative solution to  soil  exchange and for an improvement from the
ecological point of view.

Klockner Oecotec has been working on the new technology of high-pressure
soil washing since 1986. To date, some 250,000 metric tonnes of different soils
have been cleaned with three industrial-scale plants. Other plants will be started
up in the near future.  The high-pressure soil washing process is used for
rehabilitating the former sites of steel and gas works,  coking plants, chemicals
factories and  shipyards. The capacity is up to 50 metric t/h.  This technology
can be used both in the form of a mobile plant on site and as a stationary plant
in a waste disposal centre.  It is characterized by a high degree of acceptance
among the population which has become sensitized to matters of pollution.

The high-pressure soil washing plant consists of sixty 40-foot containers  or
modules.  The single containers can  be transported either by truck or train.
Complete dismantling and re-construction of the plant including transportation
from one site to another takes about two weeks. As the plant is supplied with
power from its own diesel generators,  it is not reliant on the public supplies.

Thanks to its modular design, the plant may be readily adapted to changing soil
conditions and alternating contamination.
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Although C-G Process economics are a strong function of the feed properties
and capacity requirements, commercial experience to date indicates that a
complete C-G Unit can be built and operated for about $50 per dry ton of solids
processed.
B.E.S.T. SOLVENT EXTRACTION TREATMENT OF TOXIC
SLUDGE, SEDIMENT AND SOIL

Larry D.Weimer
Resources Conservation Company
3630 Cornus Lane
Ellicott City, MD 21043
USA
Tel: (301) 596-6066

This paper described the current status of the Resources Conservation Com-
pany (RCC) B.E.S.T. solvent extraction process. The latest bench and pilot scale
treatability test data were presented, demonstrating the excellent removal ef-
ficiency of  this process for a wide range of contaminants including
polychlorinated biphenyls (PCBs), polynuclear aromatic hydrocarbons (PAHs),
and pesticides.

Development of the B.E.S.T. process for treating hazardous oily wastes began
in 1984 following reauthorization of the Resources Conservation and Recovery
Act (RCRA).  Laboratory work by RCC demonstrated that the process can
separate RCRA-listed petroleum refining oily sludges Into three fractions; oil-free
water; recyclable oil; and dry, oil-free solids. A second-generation pilot plant
was designed, constructed, and operated to demonstrate the feasibility of this
process for treating oily sludges.

Based on data from the operation of this second-generation pilot unit, RCC
constructed a commercial scale B.E.S.t.  unit designed to treat petroleum
refining sludges (pumpable sludges). In  1987, this transportable B.E.S.T. unit
completed the cleanup of 3700 cubic yards of acidic, oily, PCB-contaminated
sludges at the General Refining Superfund site near Savannah, GA.

Recently, RCC constructed a third-generation pilot unit to develop data for a
B.E.S.T. process to treat non-pumpable wastes such as soils and sediments.
This unit is  currently being  operated at the U.S. Army  Corps of Engineers
Waterways Experiment Station.  This project is part of the EPA soil and debris
BOAT development program.
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INNOVATIVE CONCEPT FOR EVALUATION OF IN-SITU
TREATMENT OF CONTAMINATED SOIL AND
GROUNDWATER

Leo B. Langgaard
B. Hojlund Rasmussen Consulting Engineers and Planners
A/S Norregade 7A
1165 Copenhagen K
Denmark
Tel: 45 33 14 21 37
Fax: 45 33 14 21 77

A peninsula-shaped site in a fishing harbour situated  close to the greater
Copenhagen area was found to be contaminated with volatile aromatic com-
pounds, water-soluble organic solvents, chlorine-containing organic solvents
and hydrocarbons. Since 1914 the site has been used as a storage and handling
area. At first it as used for fuel oil products and later for organic solvents. Leaking
of materials from the storage area  uncovered the pollution and a number of
separate investigations were carried out.  The storage area has been charac-
terized horizontally and vertically with the following activities: drilling, chemical
analyses, ecotoxicdogical tests, soil characterization, groundwater modelling,
groundwater treatment, and full-scale in-situ treatment of soil and groundwater
combined with a laboratory study on the degradation potential on soil from the
actual site.

Two separate test areas (each of 25 m2) on the site were erected with strippers
down to a depth of 4 m2 in combination with air extraction units. The test area
was characterized with chemical analyses on soil and groundwater before and
after a test period of about 2 months.  Soil samples were also tested for the
content of micro-organisms.

The test results showed that values of the residual concentration in soil and
groundwater could be accepted by the Copenhagen County, especially for the
soil but also for the groundwater after treatment on site and recirculation to the
site.

As a result of the promising full-scale studies, a total full-scale in-situ and on site
treatment plant is now in the detailed planning phase. The treatment plant will
be erected in the  beginning of  1992, when the frost has left the soil and the
weather is getting warmer.
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IN-SITU GROUNDWATER REMEDIATION OF STRIPPABLE
CONTAMINANTS BY VACUUM VAPORIZER WELLS (UVB):
OPERATION OF THE WELL AND REPORT ABOUT
CLEANED INDUSTRIAL SITES

B. Herding, J. Stamm, E. J. Alesi, P. Brinnel, F. Hirschberger, M.R. Silk
Institute of Hydromechanics
University of Karlsruhe
Kaiserstrasse 12, D-7500
Karlsruhe
Germany
Tel: 0721 608 3896
Fax: 0721 608 4290

This paper presented an in-situ method that can remove strippable substances,
e.g., volatile chlorinated hydrocarbons and  BTEX, from the subsurface
groundwater zone, capillary fringe, and unsaturated zone.  The contaminated
groundwater is stripped in situ by air in a below-atmospheric pressure field within
a vacuum vaporizer Well (unterdruck-verdampfer-brunner, UVB).  The con-
taminated air employed for the stripping process and soil air removal via suction
is cleaned using activated carbon.

The UVB method uses a specially designed well with two screen sections, one
at the aquifer bottom and one at the groundwater surface. The UVB technique
produces a vertical circulation flow in the area surrounding the well, which
encompasses the whole aquifer. The general structure of the flow is represented
in longitudinal sections by numerical results. In three-dimensional views, the
calculated separating stream surfaces of the capture zone, the circulation zone,
and the downstream flowing zone are shown. Further, the sphere of influence,
the capture zone of a well or well field, and other parameters for dimensioning
a well or well field are presented using dimensionless diagrams.

The operation and the effects of the UVB technology were explained in detail as
well as the assumptions used for the numerical calculation of the three-dimen-
sional flow surrounding the wells. The numerical results were presented using
diverse plots and diagrams.

Two extended examples demonstrated groundwater and soil remediation at
sites located in the Rhine-Ruhr area and Berlin using different installations of the
UVB system. At both sites, the subsurface had been contaminated by volatile
chlorinated hydrocarbons by degreasing processes at metal treatment com-
panies. The respective UVB installations used for the remediation of the sites
and the success of the operations were demonstrated.  The decrease of con-
                                20

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air stripping and (b) without air stripping but with devices to add nutrients and/or
electron acceptors within the well to activate biodegradation in the circulation
system surrounding the well.

The circulation flow surrounding a UVB is generally represented for a vertical
longitudinal section in the direction of the natural groundwater flow by stream-
lines for different cases.  Colored photos presented a view of the calculated
three-dimensional separating stream surfaces of the different water bodies in the
outer flow field  of a UVB: the captured, the circulating, and the downstream
flowing water. For cleaning a wide plume, the corresponding water bodies for
three UVB installations in one line normal to the natural groundwater flow were
displayed.

Graphs derived  from the  numerical calculations can be used for the dimension-
ing of UVB installations.  For sites without natural groundwater flow, the sphere
of influence and the differences of the hydraulic heads between the top and
bottom of a double-screened well, through which a discharge is pumped, were
shown. For sites with natural groundwater flow, diagrams were presented
depicting the width at the top and bottom of the capture zone, the distance
between the well axis and the upstream or downstream stagnation point, the
maximum distance between two  wells between which  contaminated
groundwater cannot pass without being treated, and the ratio Qo/Q (upstream
discharge in the capture zone/total discharge through the well), which  is a
measure of the  dilution of the upstream inflow and the circulation flow. All the
latter parameters, made dimensionless by division through H, except Q0/Q, are
dependent on the ratiosQ/H2^, KnKv and a/H. Q denotes the well discharge,
H the aquifer thickness, v the Darcy velocity of the natural groundwater flow, KH
and Kvthe horizontal and vertical hydraulic conductivities and the length of the
screen section.

The advantages of the UVB technology were presented in comparison to a
standard pump and treat method and include: (1) no lowering of the ground
water level;  (2)  no groundwater extraction;  (3) no wastewater; (4) less perme-
able, horizontal  layers are  penetrated vertically;  (5) remediation of the
groundwater takes place down to the bottom of the aquifer;  (6) remediation
operation is continuous, even at low well capacity; (7) soil air extraction is
possible at  the same time;  (8) low space requirement;  (9) investment  and
operating costs are considerably lower.
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REMEDIATION OF CONTAMINATED SEDIMENTS IN THE
NETHERLANDS

H.J. van Veen
TNO Netherlands Organization for Applied Scientific Research
P. O. Box 342
7300 AH Apeldoorn
The Netherlands
Tel: 31 55 493 493
Fax: 31 55 419 837

H.J. van Hasselt
NBM Bodemsanering B.V.
P. O. Box 16032
2500 The Hague
The Netherlands
Tel: 31 703814331
Fax: 31 703834013

In the 1960s, the Dutch Water Boards were confronted with a deteriorating water
quality. Consequently, several actions were taken to reduce the discharge of
contaminants, such as heavy metals and organic micropollutants. At the time,
it was not realized that not only the surface water, but also the suspended matter
and sediment were polluted. Today, however, we are well aware of the sediment
being contaminated  in many watercourses. In the Netherlands, contaminated
sediments are mainly a dredged-sludge problem: many Dutch watercourses
must be dredged for nautical reasons and for water management. This means
that remediation of contaminated sediments in the Netherlands refers specifi-
cally to dredged-sludge remediation. Until a few years ago, all dredged material
was disposed of in confined disposal facilities.  Recently, treatment technology
has been applied to  improve the quality of the dredged sludge. Thus, several
harbors that were seriously contaminated with PAHs, oil, and metals have been
remediated.  Their remediation included the dredging  and  processing of the
sludge by classifying and dewatering into a fraction for beneficial use, and into
a concentrate for disposal. The WaterBodem Groep  Nederland (WBGN  =
Aquatic Soil  Group  Netherlands)  specializes in  dredging and treating  con-
taminated sediments.

Since  1985, technology has been applied to reduce the quantitative volume of
contaminated dredged sludge to be disposed.  The applied process consists of
                                  24

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include Hd from the reduction of chlorinated organics such as polychlorinated
biphenyls (PCBs) and methane and ethylene from reduction of straight-chain
and aromatic hydrocarbons. The absence of free oxygen in the reactor prevents
the formation of dioxin compounds.

ECO LOGIC has set up a demonstration facility for processing polyaromatic
hydrocarbons (PAH) and PCB-contaminated harbour sediments in Hamilton,
Ontario, and has been conducting destruction tests during the spring of 1991.

The demonstration-scale reactor is 2 m in diameter and 3 m tall and is mounted
on a 15 m drop-deck trailer.  A scrubber system and recirculation gas heating
system are also mounted on the trailer, as well as the electrical control centre.
A second trailer holds a propane boiler and waste pre-heating vessel. The boiler
also accepts a small portion of the scrubbed dechlorinated recirculation gas as
fuel. The processing rate for the demonstration unit is 4-5 kg/min.

Results from the demonstration testing including destruction efficiencies ob-
tained and processing costs estimates were discussed in the paper. The com-
plete demonstration program will consist of 15 characterization tests of short
duration and longer duration performance tests.
 DETERMINING THE APPLICABILITY OF X*TRAX  FOR
 ON-SITE REMEDIATION OF SOIL CONTAMINATED
 WITH ORGANIC COMPOUNDS

 Carl Swanstrom
 Chemical Waste Management, Inc.
 Geneva Research Center
 1950S. Batavia
 Geneva, IL 60134
 USA
 Tel: (708) 573-4578
 Thermal desorption is more and more being considered as a suitable technology
 for organically contaminated soils.  This paper focused on the types of con-
 taminated soils that are likely candidates for thermal desorption   The data
 presented and conclusions drawn applied only to the patented X*TRAX process
 developed by Chemical Waste Management, Inc. (CWM).

 The various soil characteristics such as soil type, debris, moisture and naturally
 occurring organic matter that affect performance were discussed. Results from
 laboratory and pilot scale tests were presented.  Typical removal efficiencies for
 PCB  volatile organics, semi-volatile organics, pesticides  and metals were
 reported.  Applicability  of the X*TRAX process to industrial wastes such as
 refinery wastes was also included.

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DEMONSTRATION OF FLAME REACTOR TECHNOLOGY

John F. Pusateri and Regis J. Zagrocki
Horsehead Resource Development Co., Inc.
300 Frankfort Road
Monaca, PA 15061
USA
Tel: (412) 773-2279
The HRD FLAME  REACTOR high-temperature metals recovery process was
demonstrated in March 1991 underthe EPA's Superfund Innovative Technology
Evaluation (SITE) program on a secondary lead smelter (SLS) rotary kiln soda
slag from the National  Smelting and Refining (NSR) Superfund site In Atlanta^
Georgia.  The SITE demonstration proved the ability of the FLAME REACTOR
process to recover metals in a salable oxide form and to produce a non-hazard-
ous vitrified slag. The detailed cost analysis for the HRD technology is continu-
ing.
Seventy-two tons of the SLS waste were collected, packaged, manifested and
shipped to Monaca from the Atlanta site. The waste was then dried and crushed
prior to feeding to the FLAME REACTOR process. The natural gas-fired process
then subjected the waste to high-temperature (> 1500°C) reducing conditions,
in a high-intensity, water-cooled furnace, to fume the volatile heavy metals and
fuse the slagging  materials.  The reactor off-gases then passed through a
cyclonic separator to remove the molten slag from the gaseous components;
the slag was then tapped from the separator and cooled on a vibratory conveyor.
The metal  fume-laden gases were combusted with air to form a paniculate
 metallic oxide, which was  recovered in a baghouse.

 During the demonstration, the SLS waste, containing about 8% lead, was
 converted to oxide assaying at about 20% lead and slag which easily passed
 the TCLP test.  The oxide is recyclable for recovery of lead metal values. The
 high-sodium content slag  exhibited poor physical integrity until silica flux addi-
 tions were made up to about 20% of feed weight. Extensive sampling conducted
 during the  demonstration  test also confirmed that the process stack gas emis-
 sions are all well within regulatory limits.

 Cost projections based on the demonstration test results for processing the NSR
 waste and a related stockpile at the Pedricktown, NJ,  Superfund site (about
 10 000 tons) indicate a net cost of $200-250Aon of raw waste, including drying
 and crushing, FLAME  REACTOR processing, product handling, and sale of the
 crude oxide. Not included are waste destocking, shipping, and slag disposal.
 HRD is developing costs  for constructing a "transportable" FLAME REACTOR
 unit for location at various Superfund sites.
                                  28

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ISV cost categories include:  1) treatability testing at engineering-scale ($40-
80 000 depending on contaminants and analytical requirements), 2) mobilization
and demobilization ($125-200,000 depending on transport distance), and 3)
vitrification operations ($300-400/ton depending on price of electricity, amount
of water present, and depth of processing).  Costs are not included for site
characterization, permitting/ARARs compliance, remedial design, site prepara-
tion, and other non-direct ISV activities.

The ISV technology is  capable of meeting national and state ARARs.   It is
considered highly protective of human health and the environment, and enjoys
excellent regulatory and public acceptance.

ISV technology has been selected as a preferred technology at ten private,
EPA-Superfund, and DOD sites.
 RAPID REMEDIATION OF A FORMER COKING PLANT SITE

 Ulrich Jacobs
 RWE Entsorgung AG
 Bamlerstrasse 61
 D-4300 Essen 1
 Federal Republic of Germany
 Tel: 09 49 201 31
 Fax: 09 49 201 3192450

 Within the framework of a risk assessment carried out in 1987, the soil of a coking
 plant site in Essen, shut down at the end of the 1950s, was found to be heavily
 contaminated down to a depth of 8 m with coking-plant-specific contaminants
 (PAHsandBTXs).

 The risk potential for soil, air and groundwater was considerable. At the end of
 1989, the property owner, the former coking plant operator, commissioned RWE
 Entsorgung AG to plan and execute the remedial action.

 On the basis of a remedial investigation, with the participation of experts and in
 coordination with the competent authorities, an integrated remediation concept
 was set up which was used for license application and defined the sequence of
 the individual remedial steps.

 The concept comprised ex-situ remediation, i.e., excavating the soil material (silt
 and fine sand)  layer by layer, and analytically  controlled soil classification
 (uncontaminated or contaminated), as well as decontamination by thermal
 treatment  in the Netherlands.
                                   30

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SANITATION OF THE CRESOL ACCIDENT IN THE AREA
SYLSBEK, HIGHWAY A-1, WEST GERMANY

Christoph Tiebel
ITU GmbH Hamburg
Amsinckstr.45
2000 Hamburg 1
Germany
Tel: 040 230307
Fax: 040 230569

Hannes Parti
TBU GmbH Innsbruck
Defreggerstr.18
6020 Innsbruck
Austria
Tel: 0512 493733
Fax: 0512 493022

In January 1989, the driver of a hazardous material transporter spilled about
5,000 liters of ortho-cresol (ortho-methylphenol) onto a parking area of the
highway. Two tents were built over the area to reduce toxic gaseous emissions.

Because of the fact that the contaminated soil would not be accepted anywhere,
the idea of biological on-site treatment was brought up. ITU got the job  of
providing concepts, managing and supervising the sanitation. ITU also worked
out a feasibility study in which all sanitation and disposal possibilities were
discussed. The perferred alternative included disposing of highly contaminated
soil at a hazardous-waste dump, mixing the large amount of less contaminated
soil with compost and biodegradation on site in ventilated containers.

Circumstances did not allow the start of this solution. Inhabitants and politicians
of the area were afraid of this "combination of poison and bacteria" and wanted
to have a "fast" possibility to get rid of the problem. But afterwards there were
 problems with transportation of the material because inhabitants did not want
to have any poison trucked  through their area. The final decision then was
washing highly contaminated soil, packing and disposing all material in gasproof
 "big bags" and storing it in a hazardous waste dump.

Waste compost filters for the ventilation of the tent were installed and worked
 more than satisfactorily for the whole time.

 After 3 weeks there was evidence of the fact that the contamination of the
 stockpile was a lot higher than first estimated by the authorities, and the washing
                                  32

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m3 (12,000 Tons) of polycyclic aromatic hydrocarbon (PAH) contaminated soil
were excavated and stored under secure conditions. The storage facility in-
cluded a concrete pad and plastic cover to prevent release of the contaminants
and infiltration of the precipitation, respectively.

This site is under the jurisdiction of The Quebec Ministry of the Environment
(MENVIQ)  The Plant was ordered by MENVIQ to propose a cleanup technology
and to initiate the cleanup by March 1991.  MENVIQ required compliance with
a list of criteria "B." These criteria (in mg/Kg) limit Mineral Oil and Grease levels
to 1000, Naphthalene and Phenanthrene to 5, and total PAHs to 10.  Some
specific PAHs, assumed or proven to be carcinogenic, are limited to a maximum
concentration of 1 mg/Kg.

Due to the heterogeneity of the soil, the screening analysis indicated that these
levels for some samples were exceeded.

Several remediation technology options were reviewed  before the technology
selection was made. Treatment processes were studied  and sites visited by the
project team.

For studying the feasible remediation options, a pilot scale particle separation
study was carried out at Union Carbide's Technical Center. It was hypothesized
by the members of the project team that separation of the soil into size fractions
would make the treatment simple, and could possibly reduce the volume
remaining for washing and/or off-site disposal. Thus, a sequential combination
of size separation, washing, and treatment/disposal technologies offered  a
viable, low-cost management option.

Based on the results of the laboratory, pilot, and field experiment, a full scale soil
treatment process was designed and  implemented. The full scale implementa-
tion of the project was contracted to Lavalin Envirotech Inc. of Montreal, Quebec.
                                   34

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A major problem has occurred at the site because the treated material becomes
"quick" when water is applied. One can walk across the material but slight
vibrations result in loss of bearing strength. The reasons for the "quick  condi-
tions are still being investigated. Whatever the reason, the treated material
cannot be used as backfill as originally conceived.

As to the applicability and effectiveness of the process used at Wide Beach,
conclusions cannot be totally drawn until all the costs have been accounted and
a total review of the data performed. The treatment system appears to be
reducing the PCB levels to undetectaWe levels in the soil (approximately 4 ppb).
 BIOREMEDIATION DEMONSTRATION AT THE COAST
 GUARD FACILITY, TRAVERSE CITY, MICHIGAN

 John T. Wilson, Steven R. Hutchins, Don H. Kampbell
 R.S. Kerr Environmental Research Laboratory
 U.S. EPA
 Ada, OK 74820
 USA
 Tel: (405) 332-8800

 The efficacy and relative costs of three distinctly different approaches for
 bioremediation of fuel spills have been evaluated at a U.S. Coast Guard Air
 Station in Traverse City, Michigan. The water table aquifer underlying the Air
 Station is in medium sand. Two large plumes emanate from an aviation gasoline
 spill and a jet fuel spill.

 A portion of the spill of aviation gasoline was remediated  using conventional
 practice with hydrogen peroxide 500 to 1,000 mg/L A portion of the spill of JP-4
 jet fuel was remediated using innovative technology that supplied nitrate as an
 electron acceptor for microbial metabolism 40 to 50 mg/L Another portion of
 the aviation gasoline spill was remediated through bioventing. Bioventing is a
 modification of vacuum extraction that uses biodegradation in the unsaturated
 zone to destroy the vapors recovered during vacuum extraction. Bioventing was
 applied to an area of the aviation gasoline spill where most of the fuel was trapped
 in the capillary fringe above the water table. The rate of injection allowed 8 to 24
 hours residence in the unsaturated zone before the air vented to the atmosphere.

 All three technologies successfully reduced the concentration of carcinogenic
 alkylbenzenes in groundwater below federal drinking water standards. Air emis-
 sions from the demonstrations were acceptable. However, none of  the tech-
 nologies reached total petroleum hydrocarbon standards (e.g., 10 to 100 mg/kg)
                                   36

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as 1.439 mg/l. Other parameters encountered during site investigations are as
follows:
           Parameter        Maximum Value Identified

              NH3                  118 mg/l

              TKN                  121 mg/l

              NO3                   13.8 mg/l

              TSS                 1510 mg/l

              p                      17.8 mg/l

              pH             Between 3 and 8 Units

Various metals were also encountered In the landfill leachate. Specific metals
of concern included arsenic, chromium, copper, cyanide, lead, mercury, and
zinc.  The concentration of these metals was generally minor, typically lower
than 50  parts per billion. The treatment plant was provided with enforceable
discharge limits by the State of Ohio.

Operation of the treatment plant consists of chemical precipitation for metals
contained within the influent stream, followed by biological treatment for the
organic, biodegradable portion, and activated carbon for the refractory or-
ganics.
 FIELD DEMONSTRATION OF ENVIRONMENTAL.
 RESTORATION USING HORIZONTAL WELLS

 B.B. Looney, D.S. Kabach, and J.C. Corey
 Westinghouse Savannah River Company
 Savannah River Laboratory
 Aiken, SC 29808
 USA
 Tel: (803) 725-5190

 Under sponsorship from the U.S. Department of Energy, technical personnel
 from the Savannah River Laboratory and other DOE laboratories, universities
 and private Industry have completed a full scale demonstration of environmental
 remediation using horizontal wells.  The 139 day long test was designed to
 remove volatile chlorinated solvents from the subsurface using two horizontal
 wells. One well, approximately 90m long and 45m deep drilled below a con-
                                 38

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3  The operational problems of the waste water treatment In the large chemical
industry facility connected with the bulking of activated sludge resulted after
laboratory tests in the modification followed by the spontaneous carbonatlon.
The efficiency of the biological step increased from 75 to 95 percent (BODs); the
carbonated sludge connecting microcrystals of calcium carbonate improved Its
settling and dewatering  properties totally. The leachate properties of the
sludge - the mobility of heavy metals (zinc, mercury) - decreased. The improved
efficiency has been achieved on the account of the higher operational costs, but
not more than by 3 percent (lime is being used for the neutralization of waste
water in flow in any case).
CATALYTIC OXIDATION FOR EMISSIONS CONTROL OF
SITE REMEDIATION ACTIVITIES

Captain Ed Marchand
U.S. Air Force
HQ AFESC/RDVW
Tyndall AFB, FL 32403
Tel:  (904)283-6023

The presentation summarized the results of three field tests using catalytic
oxidation for emissions control. The remediation activities are pilot- and full-
scale testing of air stripping and also a pilot scale soil vapor extraction system
test. Costs of catalytic oxidation vary from one-ninth to more expensive than
activated carbon for emissions control options for the different remediation
processes.  The catalytic oxidation process is extremely dependent on not only
the contaminants and their concentrations, but also any poisons that may be in
the airstream. It is well known that different catalyst chemical formulations are
 neded for  different  target contaminants to be oxidized.   However, different
 reactor types may also be needed (i.e., a fluldized bed for higher concentrations,
 or with particuiates in the air stream).  Information on the long run operation of
a fluidized bed catalytic oxidation unit used to clean 1200 cubic feet per minute
 of trichloroethylene contaminated air from an air stripping operation was also
 presented.

To support the field  activities the Air Force has been working in two areas. The
first area includes development of poison-resistant catalysts. Two formulations
 have shown promise at the lab scale. The second area includes development
 of a catalyst testing and  selection protocol to ensure the optimum catalyst is
 used for a given waste stream. A field test of the protocol and the new catalyst
 formulations is planned for May 1992 when the Air Force will test a new air
                                  40

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Waste compressed gas cylinders represent one of the most hazardous waste
materials. Potential hazards include all those which are associated with other
chemical wastes. Additionally, there are hazards associated with the energy of
compression and the mobility of the materials when released.

Containers used to store compressed gases can also compound management
problems. Cylinders that have been mishandled, incorrectly labeled, or other-
wise Inappropriately stored may no longer be structurally capable of containing
the gas during handling.  In addition, valves  may become damaged or in-
operable through misuse.

Additional concerns include the use of the contents and cylinder.  Research
facHities will often use common manifolds that may not restrict backflow due to
differential pressures. Dangerous combinations of gases may result. Nonstan-
dard cylinders may have been used to store incompatible gases.  In addition,
some gases or mixtures may chemically decompose over time, creating un-
stable mixtures within the container.

Historical management  methods have included burial, uncontrolled release,
detonation, valve actuation in a pressure vessel, and cold and hot tapping,
among others. Each of these methods does not provide sufficient engineering
controls  to eliminate potential uncontrolled releases, exposures to physical
and/or chemical hazards, or contingencies for valve or cylinder failure on- site.

Methods for safely managing compressed gas cylinders begin with a  simple
decision analysis to correctly classify cylinders.  Following  the analysis, the
appropriate methodology may be employed to safely manage these cylinders.
Techniques are available to provide disposal for even the most difficult cylinder
to manage: a cylinder in an advanced state of corrosion, with a nonoperable
valve and unknown contents.

Methods to safely and  successfully manage compressed gas cylinders have
been successfully employed at Superfund and federal agency sites. The paper
discussed case histories, defining the problem, evaluating the hazards, and
illustrating the actions used to safely identify, dispose, or treat these cylinders.
                                  42

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test unit it was estimated that a full-scale unit would necessarily be set at a power
dosage of 0.67 KW/gpm to achieve treatment objectives at the design condition.

The extraction wells and treatment plant were completed In November 1989.
Since the extraction was started in November of 1989, the lateral extent of
contaminant has been reduced. The treatment plant has operated with effluent
TCE  at or near the detection limit.  Power dosage In the field has generally
varied from 0.3 to 1.0  KW/gpm and hydrogen peroxide residuals (i.e., the
measured  HaCk in the effluent of  the  reaction chamber)  have varied from
about 8 ppm to over 20 ppm.

Only limited data has been gathered to date at this site. The results should be
considered site-specific and not extrapolated for other situations.
DEVELOPMENT OF BIO-SCRUBBER FOR REMOVING
HAZARDOUS ORGANIC EMISSIONS FROM SOIL, WATER
AND AIR DECONTAMINATION PROCESSES

Paul K.T. Liu
Alcoa Separations Technology, Inc.
181 Thorn Hill Rd.
Warrendale, Pa 15086
USA
Tel: (412)772-1332

The "bio-scrubber" concept was identified by Alcoa Separations Technology
Inc. (ASTI) in 1989 as an innovative emission control technology for airborne
volatile organic  carbons (VOCs).  The concept combines thin-film microbial
decomposition and traditional  granular  activated carbon (GAG)  adsorptK/e
processes on a proprietary support media. ASTI proposed development of the
bio-scrubber  through an EPA cooperative agreement under the  Superfund
Innovative Technology Evaluation (SITE) Program in January 1990.

The development project includes five major tasks:
1. Laboratory feasibility determination (completed)
2. Bench-scale operating parameter evaluation (in progress)
3. Engineering evaluation
4. Superfund site selection
5. Economic analysis and commercialization plan development

Feasibility of the technology was demonstrated in 1989 during preliminary lab
studies, which indicated that the addition of specific microbial cultures to a
                                 44

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provide a very high removal rate when they are coupled with ASESs patented
immobilized cell support system.

The basic ICB system consists of the i) bioreactor, ii) media and microbes, iii)
nutrient mix tank, iv) feed pump, and v) blower for aerobic system. There are no
moving parts within the reactor. The blowers, pumps and electrical equipment
are located in a dry, protected area adjacent to the reactor.

ICB Systems range in capacity from 2000 GPD to over 300,000 GPD. The system
is modular and can be expanded inexpensively to meet your growing needs.

High treatment capacity of an ICB system provides the benefits of easy installa-
tion,  low capital cost, minimum operating and maintenance cost.

ASES provides a full range of technical services to assure best possible treat-
ment system  for your short and long term needs. We have developed an
extensive series of laboratory treatability tests and field pilot equipment to
simulate full  scale operation of treatment processes and equipment. These
procedures are based on our thorough knowledge of water treatment processes
and design. Inexpensive laboratory tests can produce design information quick-
ly and economically, while our field pilot equipment subjects our designs to the
real-world rigors of your treatment requirements. Together or separately, these
services can provide you with the extra margin of safety required on critical
projects, and the assurance that your treatment system will  work right the first
time.
PYROKILN SYSTEM THERMAL ENCAPSULATION
PROCESS

John N. Lees
Allis Mineral Systems
1126 South 70th Street
Milwaukee, Wl  53214
USA
Tel: (414) 475-3862

Allis Mineral Systems is developing the PYRQKILN System Thermal Encapsula-
tion Process under the EPA Emerging SITE Program.  The goal is to trap toxic
metals in a controlled  melting process while incinerating organic wastes.

This research, development and demonstration program builds upon work done
in past industrial minerals and hazardous waste systems. Phase I of the project
                                 46

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METALEEPsm - THE TOTAL SOLUTION FOR ON-SITE
REMEDIATION

Werner Steiner and Barry Rugg
ART International
273 Franklin Road
Randolph, NJ 07869
USA
Tel: (201)361-8840

The Low Energy Extraction Process (LEEP8™) is a patented continuous solvent
extraction process for on-site remediation in which hydrophobic organic con-
taminants (HOC) are removed from solid  matrices.  While the process was
originally designed to remove polychiorinated biphenyls (PCBs) from sedi-
ments, it has been shown, both theoretically and experimentally, to have much
broader applications. Some of the most notorious organic pollutants that can
be  removed  in addition  to  PCBs  are: petroleum hydrocarbons (PHC),
poiyaromatic hydrocarbons (PAH), pesticides, wood preserving chlorophend
formulations and tars removed (leached) from contaminated soils, sediments
and sludges.

ART International has developed an analog to LEEPsm called METLEX8"1 which
can be used to extract metals from a contaminated solid stream.  METLEXsm
can be combined with LEEPsm to remove both organic and metal contaminants.
The combined process is called METALEEPsm. METALEEPsm consists of trailer
mounted process modules in which the organic and inorganic leaching solvents
are internally recycled while the contaminants are concentrated for disposal. In
some instances, metals can be recovered for by-product value. Cleaned solid
can be returned to the environment.

The METALEEPsm process scheme consists of  organic  decontamination
(LEEPsm) followed by metals clean-up (METLEX8"1). The process is applicable
to a wide range of solid matrices containing particle sizes down to the submicron
range and having water concentrations from a few percent up to 90% +. The
leaching process is carried out in a counter-current contactor.  Fresh (organic
or inorganic) leaching solvent enters one end of the device while contaminated
solids enter the opposite end. The contaminants are transferred from the soil to
the solvent by virtue of mass transfer driven by solubility, concentration gradients
and partitioning effects.

The METALEEPsm technology can be used to remove  a  wide  range of
hydrophobic chemicals in combination with metals from contaminated solids.
By prudent choice of solvents, cosolvents and flow rates of solid and liquid
streams, the process can be used to clean up contamination such as refinery
                                 48

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bench-scale and pilot-scale, and finally with a skid-mounted mobile unit. Results
obtained from various tests have indicated successful removal of dissolved
cadmium, mercury and lead from solution.

The AECL process involves contacting contaminated aqueous solutions with a
water-soluble poiyelectrdyte.  Size enlargement of the metal ions arises by
forming selective "metal-pdyelectrolyte complexes" at specific pH and tempera-
ture conditions. The pdyelectrolyte quantities needed to achieve the desired
size enlargement and hence the separation of metal ions are generally in the
part-per-million range.  Once the desired size for the metal complex is achieved,
the solution containing the complex is then processed through a cross-flow
ultraffltration membrane. The membrane system retains the complexes as a
concentrate stream, while allowing uncomplexed ions to pass through the
membrane with the filtered water. The filtered water is recycled, or discharged
depending on the goal set out for metal contaminant removal.  The sole residue
generated by the  process is  the ultrafiltration concentrate.   The concentrate
generally constitutes 5 to 20  percent of the feed volume.   Once the target
concentration  is reached, the concentrate stream is  withdrawn for further
treatment, after which it can be readily solidified and safely disposed.

The mobile ultrafiltration unit is capable of providing filtered water rates of up to
8 gpm. The unit has undergone testing at Chalk River Laboratories. Preliminary
field trials with the  unit were completed at a  uranium mine tailings site. The unit
is currently available  for treatability/demonstration tests for contaminated
groundwater and leachate.
B&W CYCLONE FURNACE FOR WASTE VITRIFICATION

Jean M. Czuczwa, Hamid Farzan, Stanley J. Vecci, and James J. Warchoi
Babcock & Wilcox
Research and Development Division
1562 Beeson Street
Alliance, OH 44601
USA
Tel: (216) 821-9110

The Babcock & Wilcox cyclone vitrification furnace appears  well suited to
treating high inorganic content hazardous wastes (e.g., solids) which exist at
many Superfund sites.  In the first phase of a study performed under the U.S.
EPA Superfund Innovative Technology Evaluation (SITE) Emerging Tech-
nologies Program, the B&W 6 million Btu/hr pilot cyclone furnace was used to
vitrify an EPA Synthetic Soil Matrix (SSM). The SSM was spiked with 7,000 ppm
                                  50

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TCE and related  compounds pose a new challenge to biological treatment
because, unlike non-halogenated aromatic hydrocarbons (BTEX), for example,
they cannot be used as primary substrates for growth by bacteria.  Their
degradation depends upon the process of cometabollsm which Is attributed to
the broad substrate specificity of certain bacterial enzyme systems. Aeroblcally,
many enzyme systems have been purported to cooxldize TCE, but the methane
monooxygenase  (MMO) of methanotrophic bacteria, because of Its favorable
kinetics, has the most promise.

For more than four years, BloTrol has supported research at the University of
Minnesota under Richard Hanson and Lawrence Wackett on methanotrophic
degradation of halocarbons.  Although It is known that MMO can be expressed
in two different forms (soluble or membrane-bound),  BioTrd-sponsored re-
search has shown that the soluble form is responsible for extremely rapid rates
of TCE degradation.  (Stemming from this work, BioTrd has a process patent
pending.)

The goal of this Emerging Technology project is an innovative bioreactor which
effectively exploits these rapid degradation rates. Continuous-flow, bench-scale
experiments have been conducted during the first year, and the data collected
justify proceeding to the pilot scale. Design, fabrication and field testing of a 1
gpm system is planned for the second year of the project.
 BIOGENESIS8"1 SOIL CLEANING PROCESS
 TECHNOLOGY SUMMARY

 Mohsen Amiran
 BioVersal USA, Inc.
 330 South Mount Prospect Road
 Des Plaines, IL  60016
 USA
 Tel: (708) 827-0024

 BioGenesis  is an ex-situ extraction technology which washes soil using a
 complex bioremediating surfactant and water.  The process is  capable of
 extracting volatile and non-volatile oils, chlorinated hydrocarbons, pesticides,
 and other organics from most types of soil including clays. Throughput ranges
 from 20 to 35 tons per hour depending on contaminant, contamination level, and
 soil type. Costs range from $60 to $180 per ton for oils. Hazardous chemical
 cleaning costs are higher.
                                 52

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            - TRANSPORTABLE THERMAL SEPARATOR
FOR ORGANIC CONTAMINATED SOLIDS

Carl Swanstrom and Carl Palmer
Chemical Waste Management, Inc.
Geneva Research Center
1950S. Batavia
Geneva, IL  60134
USA
Tel: (708) 513-4578

The remediation of solids such as soils, filter cakes and pond sludges that are
contaminated with organic chemicals is a major problem for the environmental
industry.  Many of these wastes can be treated using a thermal  separator;
essentially, by drying them.  Chemical Waste  Management (CWM) has
developed a patented system, trademarked X*TRAX™, that thermally separates
organics from solids in an indirectly heated rotary dryer. The volatilized organics
and water are carried to a gas handling system with an inert gas (nitrogen) where
they are condensed and collected as a liquid.  The carrier gas is reheated and
recycled to the dryer in a closed loop. Only a small portion of the carrier gas is
vented to atmosphere  through carbon adsorbers to control noncondensables
in the recirculation loop. CWM has constructed a full scale transportable thermal
separator with a nominal capacity  of 125 tons per day.  This unit has been
contracted for treatment of PCB-contaminated soils at the Resolve, Inc. Super-
fund site in Massachusetts.  CWM  has been operating both a 5 ton/day pilot
system and a 2-4 Ib/hr lab scale system since early  1988. The pilot unit has
performed extensive testing on TSCA wastes in 1989 at CWM's Kettleman Hills
Facility in  central California, and  is presently testing RCRA wastes.  The
laboratory unit is available for treatability testing.
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aluminum hydroxides; phosphate Is removed as the Insoluble aluminum phos-
phate species.

Alternating current electrocoagulation is foreseen either as a primary treatment
technology (for example, for suspended solids removal) or as a "polishing"
technology for effluents to which chemicals (alum, lime) had previously been
added for gross contaminant reduction. The technology Is effective In reducing
the volume of a potentially  hazardous slurry by concentrating the clays and
metais into a readily dewaterable and filterable solid phase. Electrocoagulation
offers equivalent or slightly better treatment than chemical polymer addition and
has the added attributes of producing more readily filterable sludges without
introduction of soluble species.  In terms of solids and metals reductions, the
results achieved by electrocoagulation are far superior to those achieved by
alum addition.
LASER INDUCED PHOTOCHEMICAL OXIDATIVE
DESTRUCTION OF TOXIC ORGANICS IN AQUEOUS
STREAMS (LIPOD)

James H. Porter
Energy and Environmental Engineering, Inc.
P. O.Box215
East Cambridge, MA 02141
USA
Tel: (617) 666-5500

Organic compounds and specifically chlorinated  aromatic and unsaturated
organics are major contaminants in groundwaters. These latter species also tend
to rank high on the list of EPA priority pollutants, even at the low (g/l) concentra-
tions that they are normally found in groundwaters. The technology described
in this report has been developed under the Emerging Technologies section of
the  Superfund Innovative Technology Evaluation  (SITE)  Program to
photochemically oxidize organic  compounds in wastewater by applying
ultraviolet radiation using an excimer laser. The  photochemical reaction is
capable of producing the complete destruction of moderate to extremely low
concentrations of toxic organics in water. The energy supplied  by the laser is
sufficient to stimulate photochemical reactions between the organics  and
hydrogen peroxide employed as a chemical oxidant, causing photo-oxidation
and/or phototransformation of the toxic species to carbon dioxide, water,  and
the corresponding halogenated acid. Additionally the radiation is not absorbed
to any significant extent by the water molecules in  solution. The process has
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During the drilling operation, the auger flights break the soil  loose allowing
the mixing blades to Wend the reagent(s) and the  soil  into a homogeneous
mixture. As the auger advances to a greater depth, the soil and reagent(s) are
remixed by an additional set of augers and mixing blades located above the
preceding set on each shaft.  When the desired depth is reached, the augers
are reversed and withdrawn and the mixing process is repeated on the way to
the surface. Left behind is a homogeneously treated block of soil. Each treated
block of soJI is composed of two overlapping columns. The pattern of columns
is  extended laterally In rows of  treated  blocks,  in a  repetitive manner to
encompass the total area of the  required remediation.  The depth of the
columns, which can exceed 100 feet,  encompasses the vertical extent of the
remediation.
 TWO-STAGE FLUIDIZED-BED/CYCLONIC
AGGLOMERATING INCINERATOR

Amir Rehmat and Mike Mensinger
Institute of Gas Technology
3424 South State Street
Chicago, IL 60616
USA
Tel: (312) 567-5819

Teri Shearer
U.S. Environmental Protection Agency
26 W. Martin Luther King Drive
Cincinnati, OH 45268
USA
Tel: (513) 569-7949

Pat Duggan
Gas Research Institute
Chicago, IL 60631

Under the joint sponsorship of U.S. Environmental  Protection Agency, Gas
Research Institute, and IGT's Sustaining Membership Program, the Institute of
Gas Technology (IGT) is developing a natural-gas-based two-stage incineration
(TSI) technology for the remediation of contaminated soils at the Superfund
sites.  Although initially targeted for this limited application, the technology holds
a promise for much broader application for the disposal of such wastes as
municipal solid wastes, pulp and paper mill sludge, non-metallic automotive
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IT is testing this treatment process on a PCB contaminated soil and TCDD
contaminated soil. The soils are photoiyzed using both natural sunlight and
artificial UV light for comparative purposes. The effects of adding a photolysis-
enhancing surfactant to the soils is also being evaluated.  Biodegradation is
being evaluated on the photdytically-transformed PCB contaminated soH only.
This is because typical TCDD contamination in soils is in the low to mid parts
per billion range which makes tracking and quantitation of any photolytically
transformed contaminants difficult.

The combined technologies of  photolytic decomposition  followed  by
biodegradation of residuals offer promise of a cost-effective politically accept-
able solution for contaminated soil.  A primary feature of this technology com-
bination is the possibility of treating applicable soils in-situ. It is an alternative
to the conventional methods of treating those soils - dig and haul, which is
contrary to the goals of Superfund, and thermal incineration which encounters
significant resistance to acceptance from environmental groups and the public.
It is also  an alternative to emerging technologies such as soil flushing, soil
extraction and KPEG treatment.

Other attributes of this technology combination are relative ease in setup of
equipment, use of conventional earth  moving  equipment, no air emissions,
processing at ambient temperatures and minimal and innocuous residuals. All
of these  features make this technology combination very attractive to  the
Superfund program.

The primary area of application of this technology is sites with relatively shallow
contamination  where in-situ treatment  involving tilling of the soil and surface
photolysis can be effective. The experimental program proposed for this evalua-
tion and demonstration will yield data that can also be used for application to
sites where the soil is  excavated  and treated  in a land treatment type unit
 (spreading contaminated soil on ground for treatment).

This technology combination is expected  to be  especially cost-effective for
 smaller sites where per unit treatment costs are typically high.  Higher costs at
these smaller sites are the result of high fixed costs (mobilization, demobilization,
 capital recovery)  associated with  other treatment technologies.  This  in-situ
treatment capabilities of this technology will eliminate many of these high fixed
 cost factors and provide a viable  alternative to the "dig and  haul" treatment
 option.
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Therefore, these coupled technologies will have the added benefits of greater
acceptability and lower risk In remediation decisions.
THE AIR-SPARGED HYDROCYCLONE: A DEVICE FOR
RECOVERY OF METAL VALUES FROM MINING WASTES

Theodore S. Jordan
Montana College of Mineral Science & Technology
West Park Street
Butte,MT 57901
USA
Tel: (406)496-4112
The Air-Sparged Hydrocyclone is a recently-developed flotation machine which
is especially suited to the recovery of fine mineral particles through the froth
flotation process. The device is currently being tested at the Montana Tech
Research Center in Butte, Montana, to evaluate Its efficacy in the separation and
recovery of metallic minerals from mining/milling wastes.

Froth flotation is presently the primary method for separating metallic minerals
from their ores. It may also be applied to the extraction of mineral values from
wastes which were laid down at a time when mineral processing technology was
less advanced than it is today and significant amounts of presently-recoverable
 mineral values remained in the waste (tailings) remaining after mineral process-
 ing.
 In the flotation process, certain of the minerals in aqueous slurry are rendered
 water repellent through contact  with organic chemicals,  which are  termed
 "collectors". Other minerals remain water wetted. In the presence of  moving
 air bubbles, the water repellent minerals adhere to the bubbles and are levitated
 to the surface of the slurry, where they are skimmed off.  As a result of the
 reduced inertia of small particles,  the flotation process diminishes in efficiency
 as particle size decreases, resulting in high concentrations of otherwise floatable
 particles 50 micrometers in diameter or smaller.

 The Air-Sparged-Hydrocyclone (ASH), which was developed at the University
 of Utah by Dr. J. D. Miller, promises improved flotation recovery of small particles
 through two features, both of which increase the probability of mineral/bubble
 collision and adhesion:

 1)  Introduction of air through a porous membrane produces a very high con-
     centration of bubbles.
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The hydrocarbons and water in the dirty water storage tank are pumped to a
centrifuge, where the hazardous hydrocarbons are spun out into a pasty sludge
ready for final disposal. This process concentrates the contaminants, which are
typically one-half of one percent of the total incoming mass.

The water is then pumped through a potable water filtration system which
includes a depth filter, a water clarlfier, and two stages of activated carbon. The
water is pumped to the clean water storage tank where It is tested to assure it is
clean.
The cleansed material, less a pound or so perton of concentrate, can be returned
to the excavated site or recycled back Into the marketplace.
 SAREX CHEMICAL FIXATION PROCESS (SAREX CFP)

 William Sheehan
 Separation and Recovery Systems, Inc. (SRS)
 1762 McGaw Avenue
 Irvine, CA 92714
 USA
 Tel: (714) 261-8860

 The SRS "SAREX CFP" Chemical Stabilization and Solidification  process
 provides lime-based chemical fixation  of hazardous organic and inorganic
 sludges.  The lime is specially prepared and contains  proprietary nontoxic
 chemicals  that catalyze and control the reactions between the lime and the
 waste. Results are better than competing fixation processes because chemical
 reactions change and bind the hazardous constituents.  The technology has
 been  demonstrated at commercial sites and the vendor is experienced in
 commercial application.

 The process has been developed over a number of years to be applicable to a
 broad spectrum of organic and  inorganic  wastes.  This has proven to be
 advantageous since most on-site clean up programs focus on a sludge pond or
 impoundment that has received many different wastes over several years. Oily
 sludges and organic chemical sludges are particularly suited to the technology.
 Few, if any, fixation-type technologies actually provide the chemical bonding of
 organics that is achieved by the SRS technology. Inorganic sludges and wastes
 can be handled by the technology as well. Metals are captured in the treated
 matrix and have been shown to pass the TCLP test.
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Inc has developed an inorganic chemical complexing agent (RHM-1000) that
will remove heavy metals and/or radionuclides from industrial waste water, pond
water, ground water, or container water.

Laboratory and field test data have demonstrated that RHM-1000 efficiently
complexes essentially all the heavy metals and NORM and man-made
radionuclides.  RHM-1000 yields high Decontamination Factor values as a
flocculation agent, and is also efficient when used as a filter bed  material to
remove pollutants existing as colloids, colloidal aggregates, and submicro-
scopic particles that escape conventional filters.

RHM-1000 is currently being tested for use as a colloid  or polishing filter.
Engineering and field tests are being conducted for the purpose of:

1) evaluating removal of heavy metals from industrial waste waters

2) removal of NORM from uranium mining water, ground water and remediation
of man-made radionuclides

The methodology has application for  remediation of heavy metals or
radionuclide contaminated water and can be used in conjunction with soil and
sludge washing methods.


TECHNOLOGY SUPPORT CENTER
THE ROBERT S. KERR ENVIRONMENTAL RESEARCH
 LABORATORY

 D.S. Burden
 U.S. EPA
 Technology Support Center
 R. S. Kerr Environmental Research Laboratory
 Ada, OK 74820
 USA
 Tel: (405) 332-8800

The Superfund Amendment and Reauthorization Act (SARA) directs the U.S.
 Environmental Protection  Agency  (EPA) to conduct a program of research,
 evaluation, and demonstration of alternative and  innovative technologies for
 remedy response actions that will achieve more permanent solutions.  In-
 dividuals making  decisions concerning remedial  action options  must select
 and/or approve effective remediation activities and technologies for  each
 specific site that will be protective of human health and the environment.
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SUBSURFACE REMEDIATION TECHNOLOGY DATABASE:
A SUPERFUND TECHNICAL ASSISTANCE TOOL

D.S. Burden
U.S. EPA
Technology Support Center
R. S. Kerr Environmental Research Laboratory
Ada, OK 74820
USA
Tel: (405) 332-8800


The Subsurface Remediation Technology (SRT) Database Is a program
designed to provide site specific information concerning subsurface contamina-
tion and remediation activities presently being conducted or proposed at Super-
fund sites throughout the United States. The target audience for the SRT
Database includes:  EPA Scientists,  Remedial Project Managers, On-Scene
Coordinators, Superfund site contractors, and other key federal and  state
personnel associated with subsurface contamination and remediation activities.
The purpose of the database is to provide a single comprehensive source of
information which can be shared and compared to other sites having similar
problems or scenarios.  The SRT Database consists of five related components:
site characterization, methods of remediation, contaminants, consulting firms,
and references cited.

The site component serves as the core and has a one-to-many relationship with
the other components and Includes historical  notes, descriptions of the con-
taminants, soil, geology and hydrogeology, alternative remediation methods
considered, and the names of EPA Regional personnel associated with the sites.

The SRT Database allows searching for over 60 contaminants which are most
frequently found at hazardous waste sites. These represent contaminant clas-
ses, including: metals, pesticides, chlorinated solvents, polynuclear aromatic
hydrocarbons (PAH), hydrocarbons and derivatives, and  a general class com-
posed of such contaminants as cyanide, pentachlorophenol, and vinyl chloride.

The SRT Database also allows searching based on the type or types of remedia-
tion technology being applied at a site. The technologies included range from
the passive, such as barriers, drains, and covers, to the active, such as pump
and treat, in-situ biological, and soil vacuum extraction.
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TREATMENT OF NITROAROMATIC RESIDUES IN SOIL: A
NOVEL ANAEROBIC PROCESS

Douglas Sell
J.R. Simplot Corporation
P.O. Box 15057
Boise, ID 83715
USA
Tel: (208) 389-7265

Russell Kaake, Deborah Roberts, Don Crawford, and Ron Crawford
Center for Hazardous Waste Remediation Research
University of Idaho
Moscow, ID
USA
Nitroaromatlc compounds are used in the agricultural industry as herbicides, in
ordnance manufacturing and as precursors in a variety of chemical industry
processes.   These compounds have become  serious  environmental  con-
taminants throughout the world, and methods for their removal from soil and
water are needed. Compounds with more than one nitro group have not  been
shown to be mineralized aerobically or anaerobically. Initial microbial transfor-
mations that have been observed usually involve the reduction of nitro groups
to amines.  Reduction continues, forming hydroxylamine intermediates. Under
aerobic conditions, these intermediates react with one another and undergo
nonenzymatic oxidation to form azoxy bonds. Such polymeric compounds bind
to soH organic matter and have been found, in some cases, to be  more
mutagenic  than their parent compounds. We are investigating an anaerobic
biological treatment process for soils contaminated with nitroaromatic  com-
pounds. A complete remediation process has been developed for soils con-
taminated with dinoseb (2-sec-butyl-4,6 dinitrophend) and a similar process for
TNT (2,4,6 trinitrotoluene) contaminated soils is under investigation.
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The major advantages of this treatment process over other advanced oxidation
processes are:

1.  Approximately equal concentrations of reducing species, e~ aq and H •
   and the oxidizing specie OH •  are formed at the same time in solution.
   This allows for the simultaneous treatment of complex mixtures of hazard-
   ous chemicals.

2.  The reaction of the reactive species with most organic chemicals is very
   rapid allowing a continuous flow through treatment process of various
   water qualities, including streams with suspended sediment or suspended
   solids in amounts up to 8 to 10 percent. Removal is less affected by water
   quality in this process than in other processes.
A TRANSVERSAL FLOW PERVAPORATION SYSTEM
FOR THE REMOVAL AND CONCENTRATION OF VOLATILE
ORGANIC COMPOUNDS

Pierre Cote and Chris Lipski
Zenon Environmental Inc.
867 Lakeshore Rd.
Box 550
Burlington, Ontario
Canada
Tel: (416) 336-4605

Pervaporation is a new membrane process for the removal and concentration
of volatile organic compounds (VOCs) from contaminated water. This process
can be used to treat groundwater, leachate and wastewater containing VOCs
such as chlorinated solvents. About half of the 129 US EPA priority pollutants
are VOCs and are known to be toxic and/or carcinogenic.

In pervaporation, one side of a dense, polymeric membrane is in contact with
water containing organic compounds, while the other side of the membrane is
exposed to a vacuum. Organic compounds and water are absorbed in the
membrane and diffuse through to the other side where they are drawn off by a
vacuum. Materials passing through the membrane are contained by condensa-
tion.

The membrane is made of an organophilic polymer which exhibits high fluxes
for the organic compounds while  allowing very little permeation  of water.
 Organic  compounds are concentrated in the condensate by orders of mag-
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oxidation that occurs at  elevated temperature and pressure.   PACT, when
coupled with WAO, provides complete destruction of many toxic components
and reduces sludges to a stable, sterile, inorganic residue.

As part of the SITE demonstration, contaminated groundwater from the Syncon
Resins Site in Keamy, New Jersey, was treated at the Zimpro Passavant Testing
and Development facility (a permitted hazardous waste treatment, storage, and
disposal facility, No. WID044393114) in Rothschild, Wisconsin. All eleven priority
pollutants in the groundwater were reduced to below detection limits.  Unfor-
tunately, the Syncon Resins Site was not available for the full-scale demonstra-
tion. EPA is continuing to search for a suitable site.

WAO systems have recently been employed  in Belgium, Taiwan, Texas, and
Louisiana in the destruction of sulfide and organics accumulations in caustic
scrubbing liquors. WAO systems have been tested and are currently being built
for treatment of pharmaceutical production wastewaters in the United Kingdom
as an alternative to disposal in the North Sea. PACT systems have recently come
on-line for treatment of process wastewaters in Korea,  India, .Canada,  and in
several locations in the United States.
                                   74      *U.S. Government Printing Office: 1991 — 545-187/4056

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