ABFA
U.S. Environmental
Protection Agency
Office of Solid Waste and
Emergency Response
Technology Innovation Office
EPA/540/M-91/005 No. 7 December 1991
BilgillV
The applied technologies journal for Superfund removals and remedial actions and RCRA corrective actions
Don't Miss
Special
Supplement
to tecfe Trends
ou wilt notice that this edition
Tech Trend$ contains an
insert on "innovations m
Monitoring and Measurement
Technologies", Although the
focus of Tech Trends is usually
on innovative cleanup
technologies ready for field
application, we also wantto
bring yog news of other
Innovative tools that can assist
you In emergency response,
remediation and corrective
action.
So, we include a special
Insert that highlights a
multimedia lead risk assessment
model, afield-portable
monitoring system that links up
to an onsite computerized
locating system and improved
metals'sampling techniques for
groundwater,
- - Also, dont miss the
description ol the Cleanup
Information Bulletin Board
System (CLU-IN) on page 4 of
the supplement^ CLLMN is
designed for hazardous waste
cleanup professionals to use for
finding current events
Information about innovative
technologies, consulting with
one'another online and
[ accessing data .bases,'
I i :
dS> Printed on Recycled Paper
PCBs Destroyed by Combining
Thermal & Chemical Treatments
by Paul de Percin, (v~~\"
Risk Reduction Engineering Laboratory Q PCBs
rr" I Anaerobic
aerobic thermal processor (ATP) technology involves a l$i processor
physical separation process that thermally desorbs organics xr^
such as polychlorinated biphenyls (PCBs) from soil and Soil and sludge
sludge. The ATP process is being used in conjunction with V. ^
dehalogenation to chemically destroy PCBs in the soil at the Wide Beach Development
Site hi Brant, New York. The technology can also be applied to many other types of or-
ganic contaminants. ATP was developed by Alberta Oil Sands Technology and Research
Authority and is licensed by SoilTech, Inc.
At Wide Beach, the transportable ATP unit processes about 10 tons of contaminated
soil per hour. The ATP system heats and mixes contaminated soils, sludges and liquids in
a unit that uses indirect heat for processing. The processor contains four separate internal
thermal zones: the preheat, retort, combustion and cooling zones. For this demonstration,
the contaminated soils are sprayed with a diesel fuel and oil mixture, containing alkaline
polyethylene glycol (APEG) reagents before entering the preheat zone. The oil mixture
acts as a carrier for the dehalogenation reagents.
In the preheat zone, water and volatile organic compounds (VOC) vaporize. At the
same time, the reagents dehalogenate or chemically break down chlorinated compounds
(including PCBs). The vaporized contaminants and water are removed via a vacuum to a
(see PCS page 2)
Innovative Treatment!! Selected for Superfund Sites
Contaminated by PCBs
.o
1
Q
Q
O
DC
"5
Dechlorination In Situ Solvent Thermal Bloremediatlon In Situ
Flushing Extraction Desorptlon Vitrification
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SITE Subjects
Flame Reactor for Hecpry Metdls
by Marta Richards, Risk Reduction Engineering Laboratory
m
Metals
Flame Reactor
Industrial
residues
• he Horsehead Resource Development (HRD)
Company, Inc., Flame Reactor is a patented and
proven high temperature thermal process that safely
treats industrial residues and wastes containing met-
als. As a Superfund Innovative Technology Evalua-
tion (SITE) Demonstration, approximately 72 tons of
waste material containing heavy metals from the Na-
tional Smelting and Refining site in Atlanta, Georgia,
were successfully treated with the HRD Hame Reactor. The waste material was a
granular secondary lead smelter blast furnace soda slag containing approximately
15.0% carbon, 10.3% iron, 12.2% sodium, 5.3% sulfur, 5.4% lead, 5% silicon,
2.5% chlorine, 0.4% zinc, 0.05% arsenic, 0.04% cadmium and approximately
15.0% water. ;
For this SITE demonstration the material was dried and passed through a
hammermill prior to treatment. This demonstration testing vfas run with natural
gas. At high temperatures inside the HRD Flame Reactor, ttie volatile metals in
the waste were volatilized and the organic compounds wereidestroyed, leaving a
non-leachable slag containing the non-volatile metals and gases, including steam
and volatile metal vapors. The metal vapors further reacted and cooled in the
combustion chamber and cooling system to produce a metal-enriched oxide that
was collected in a baghouse. The resulting metal oxides can be recycled to re-
cover the metals. Results from the demonstration are quite good.
Although samples of raw feed failed the Toxicity Characteristic Leaching
Procedure (TCLP) test due to high cadmium and lead levels, all samples of pro-
cessed waste slag passed the TCLP test for all metals. The processed waste slag
can be used as fill material. Lead and zinc were concentrated in the baghouse
dust, which potentially could be recycled for its lead content The process
showed better than 90 percent recovery for both lead and zinc. The lead and zinc
concentrations in the waste feed, the baghouse dust and the separator slag are
shownbelow. • < .; i !
Waste Feed Slag • Baghouse
Total Metal (% weight) (% weight) < (% weight)
Lead 5.4 0.6 j 17.4
Zinc 0.4 0.2 ,. ; 1.4
Overall, the weight of the waste was reduced by approximately 30%, largely
due to removal of water and carbon during pretreatment and treatment. SO2
emissions were high due to the amount of sulfur in the waste, but the SO2 emis-
sions could readily be controlled with the use of a scrubber. |
The HRD Flame Reactor technology can potentially be! applied to many
types of granular solids, soil, flue dust, slag and sludge containing high concen-
trations of heavy metals and hazardous organics. ;
An Applications Analysis Report and a Technology Evaluation Report de-
scribing the complete HRD SITE Demonstration will be available in the Spring
of 1992. For more information now, call Marta Richards at>the Risk Reduction
Engineering Laboratory on FTS 684-7783 or 513-569-7783.
PCB (from page 1)
preheat vapor cooling system consisting of a cy-
clone, condenser and a three-phase preheat separa-
tor. The noncondensed light organic vapors are
then fed by a blower directly into the combustion
chamber of the processor. The oil fraction is re-
cycled to a reagent blending tank, and recovered
water is sent to the onsite treatment system.
From the preheat zone, the hot, granular sol-
ids pass through a sand seal to the retort zone.
Here, heavy oils vaporize and thermal cracking of
hydrocarbons forms coke and low molecular
weight gases. The vapor stream from the retort
zone is removed via a vacuum and passes first
through a two-stage pair of cyclones to remove en-
trained particles. These dusts and fines are blended
with the treated soil. The vapor is then cooled by
oil circulating in two packed columns, acting as a
two-stage direct contact condenser for the higher
boiling point compounds. The uncondensed va-
pors are then cooled in a water-cooled noncontact
condenser and pass through a three-phase separa-
tor. The final noncondensable gases are returned
to the combustion chamber. The oil phase is com-
bined with the condensate from the packed col-
umns. This oil condensate is then sent to the re-
agent blending unit to mix with the APEG re-
agents. The blend is pumped at a measured rate
and is applied to the untreated soils in the feed
chute of the processor. Condensed water is
pumped directly to the onsite treatment system.
The coked soils pass through a second sand
seal into the combustion zone. Here the coked
soils are combusted and either recycled to the re-
tort zone or sent to be cooled hi the cooling zone.
Flue gas from the combustion zone is treated in a
system consisting of a cyclone and baghouse that
removes participates, a scrubber that removes acid
gases and a carbon adsorption bed that removes
trace organics. The treated flue gas is then dis-
charged to tiie atmosphere through a stack.
Treated soils exiting the cooling zone are quenched
with scrubber water and are then transported by
conveyor to an outside storage pile.
The ATP unit removed over 99% of the
PCBs hi the contaminated soil (original concentra- •
tions of 50 to 100 parts per million), resulting in
PCB levels below the desired cleanup concentra-
tion of 2 ppm. The ATP does not appear to create
dioxins or furans. Additionally, no volatile or
semivolatile organic degradation products or
leachates were detected hi the treated soil.
For more information, call Paul de Percin at
the Risk Reduction Engineering Laboratory on
FTS 684-7797 or 513-569-7797.
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A Supplement to TECH Htf!if0£
December 1991
Innovations in
^•WK. JwWw»^BBF^Wi^8PTMFwl ^tiF WWl^tJP' MJBIW
innovative Site investigation
techniques are of increasing
interest to those attempting
to reduce the cost and
increase the effectiveness of
site remediation. This is one
of a series of occasional
supplements to Tech frewcfe, ,
the applied technologies
, f ournal for Superftind remov«"
als and remedial actions and
RCRA corrective actions.
U*S» Environmental Protection
Agency
Otflee of Solid Waste and
emergency Response
-Technology Innovation Office
Walter W* Kovalick, fr^ ph,D,
Director ;,-
Field-Ready Hardware Links Portable XRF
with Automated Locating Systems
By William Engelmann,
Environmental Monitoring Systems Laboratory
EPA now has field-ready hardware that links the field portable X-ray
fluorescence (FP-XRF) analyzers of inorganic (metallic) compounds with
automated locating (geographical-positioning) systems. This link has the
potential of truly revolutionizing FP-XRF operations. The analyst can see
a "growing picture" of the "hot spots" or "hills" on the contour diagram
as it is developed on a computer screen on-site. Further, the ability to
gather additional data points, as needed, while still in the field is another
major advantage over earlier field screening methods. Thus, the systems
can gather field analytical data in real time at the site and keep computer
files of the coordinate points of the measurement. The automated
locating system was developed earlier by Oak Ridge National Labora-
tory, which named it the ultrasonic ranging and data system (USRADS).
USRADS is made up of a surveyor's backpack, several tripod-
mounted receiver modules and a master receiver-computer system,
located in a van or trailer. The backpack, worn by a surveillance
member, transmits data ultrasonically to the receiver-computer. Up to
see XRF Links, page 3
Lead Risk Assessment Model Helps Set Multimedia Cleanup Standard
By Harlal Choudhury, Environmental Criteria and Assessment Office, Cincinnati,
and Christina Haviland, Labat Anderson, Inc.
EPA has developed a Lead Uptake/Biokinetic (UBK) Model that is used to assess human health risk based on
multimedia lead contamination. Lead is a common contaminant at Superfund sites. However, it has been
difficult to assess health risk from lead because of the complexity of the issues. Now, the UBK model provides
a method for'predicting blood lead levels in populations exposed to lead through multiple pathways. The
see UBK, page 3
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A Supplement to ffiCif flf f NfXIS
December 1991
Improved Metals Sampling Techniques for Groundwater
By Robert Puls, Robert S. Kern Environmental Research Laboratory
EPA has tested sampling tech-
niquesfor inorganics in ground-
water that minimize the distur-
bance ofthesubsurfaceground-
water environment. This has
plagued the acquisition of rep-
resentative and accurate heavy
metal concentrations for risk
assessments at hazardous waste
sites. Intuitively, itmakessense
to minimize disturbance of the
sampling zone to obtain repre-
sentative and accurate data and
excessive turbidity has been
the most common manifesta-
tion of disturbance. Excessive
pumping or purging relative to
local hydrogeological conditions
is the most common cause of
artificial turbidity. Aeration and
oxidation can be both causes
and effects of excessive turbidity.
EPA's Robert S. Kerr Envi-
ronmental Research Laboratory
(RSKERL) has field tested sam-
pling techniques that call for:
(1) isolating the sampling zone
with inflatablepackerstomini-
mize purge volume; (2) pump-
ing at a low flow rate to mini-
mize aeration and turbidity;
(3) monitoring water quality
parameters while purging to
establish baseline or steady-
state conditions to initiate sam-
pling; (4) maximizing pump tub-
ing thickness and minimizing
length to exclude atmospheric
gases; and, (5) using filtration for
estimating [dissolved species and
collection of unfiltered samples for
estimates of contaminant mobility.
The above sampling techniques
were evaluated at three geologi-
cally-differentsites. The Final Creek
Site in Arizona, contaminated with
copper mining wastes, is an upland,
extremely heterogenous alluvial
aquifer with sediment sizes ranging
from fine sand to coarse gravel. The
Saco, Mairie, Site, contaminated
with chromium waste from a leather
tannery, consists of glacial till de-
posits underlain by a sloping frac-
tured bedrock surface. The Eliza-
beth City, North Carolina, Site, con-
taminated with acidic chromium
wastes from a chrome plating shop,
is on Atlantic coastal plain sedi-
ments characterized by complex and
variable sequences of surficial sands,
silts and clays. Results showed that,
in wells deeper than 30 feet, a blad-
der pump was most successful in
producing representative and repro-
ducible resjjlts, regardless of filter
poresize. In shallow wells less than
30 feet deep, a peristaltic pump
consistently produced the most
reproducible results. Pumping
rate was the single most impor-
tant parameter affecting equili-
brated turbidity values and con-
taminant concentrations. Equili-
brated turbidity levels observed
at the three sites ranged from 1
to 58 nephelometric turbidity
units. Turbiditydifferenceswere
strongly related to geology and
water chemistry.
A down-hole camera was
used during purging and sam-
plingto evaluate the disturbance
caused by pump tubing em-
placement and pumping down-
hole. Little impactwas observed
when a peristaltic pump was
turned on after both the pump
tubing and the camera had been
left in the screened interval over
night. Emplacement of the cam-
era itself created the greatest tur-
bidity and required overnight
reequilibration in the absence of
pumping.
The demonstration results
strongly argue for dedicated sam-
plingequipmentandtechniques.
For more information, call Bob
Puls at RSKERL on FTS 743-2262
or 405-332-8800.
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A Supplement to TM€H TRSN&S
December 1991
UBK
from page 1
blood lead levels can then be
used to guide risk assessors in
determining cleanup levels that
will protect current and future
populations at the site.
Infants and young children
are the most vulnerable popula-
tions exposed to lead and are
the focus of EPA's risk assess-
ment efforts. Both behavioral
and environmental data are
needed to run the model. Be-
havioral data include the time
the population spends indoors
vs. outdoors, gardening habits,
the consumption of produce grown
on site and pica behavior. Environ-
mental data include lead concen-
trations in indoor air, outdoor air,
drinking water, soil and dust. Sev-
eral age-specific default parameters
are used including breathing vol-
ume, soil intake and percent lead
absorption via different pathways.
These defau It val ues along with the
site specific data are used to calcu-
late route-specific lead uptakes. The
sum of all these route-specific up-
takes isthetotal lead uptake, which
is applied to the model's curve to
predict blood lead levels.
The UBK model has been tested
at several Superfund sites since its
inception, including the Bunker Hill
Site in Region X. Bunker Hill is an
inactive smelter site located in a
residential area. Lead contami-
nation has been found in the soil
as well as in area homes. Media-
specific lead concentrations are
being used with the UBK model
to define an appropriate reme-
dial design for the site.
The UBK model is under EPA
Science Advisory Board review,
and draft copies are available for
use at Superfund sites through
the EPA's ten Regional offices.
For more information, contact
Harlal Choudhury at EPA's Envi-
ronmental Criteria and Assess-
ment Office at FTS 684-7536 or
513-569-7536.
XRF Links
fro>m page 1
15 tripod-mounted stationary
units can be set up around the
perimeter of the site. Each has
an ultrasonic receiver and a
radio transmitter. Any one of
these modules can receive ul-
trasonic data signals and each
has a unique radio-transmitting
frequency to allow the master
receiver to identify which unit
received the ultrasonic signal.
The master receiver has 15 radio
receivers, each tuned for a correspond-
ing stationary module. Finally, atrans-
ceiver allows voice communication
between the surveyor who walks the
site and the receiver-computer op-
erator in the mobile van.
This advanced version of
USRADS can link up with other ana-
log analytical devices as well. In
addition, another interface within
the master receiver allows connec-
tion to any personal computer with-
out the need for a computer inter-
face card. This allows any IBM-
compatible computer to be di-
rectly connected, including lap
top portables (most of which have
no expansion slot for plug-in in-
terface cards).
The advanced prototype of
the USRADS is expected to be
delivered to EPA's Environmen-
tal Monitoring Systems Labora-
tory-Las Vegas (EMSL-LV) by late
1991. For information, contact
William Engelmann, EMSL-LV on
FTS 545-2664 or 702-798-2664.
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Cleanup Information
Bulletin Board
November 11991
EPA
The Cleanup Information Bulletin Board System (CLU-IN) is designed for hazard-
ous waste cleanup professionals to use for finding current events information about
innpvative technologies, consulting with one another online, and accessing
databases. CLU-IN is used by those involved in the cleanup of Superfund and
Resource Conservation and Recovery Act corrective action sites, including EPA,
other Federal Agency and State personnel, consulting engineers, technology
vendors, remediation contractors, researchers, community groups, and individual
citizens. j
Features of CLU-IN i
• Electronic message capabilities (which may be communicated to large audi-
ences or to individual users, depending on the preference of the sender)
• Bulletins that can be read online (such as summaries of Federal Register notices
on hazardous wastes, descriptions and listings of EPA documents, a calendar of
EPA training programs, directories of EPA experts on|hazardous waste cleanup,
and articles from Tech Trends, EPA's newsletter on innovative technologies)
• Files that can be downloaded for use on the user's own computer (directories,
databases, models, a listing of National Priorities List1 sites, and documents such
as abstracts of selected Superfund directives and reports and the Innovative
Treatment Technologies Semi-Annual Status Report)]
• Online databases that can be searched on CLU-IN (such as a databases of EPA
technical experts and training course announcements)
Special Interest Group Areas
CLU-IN also has a number of special interest groups (SIGs) or sub-areas with all the
capabilities listed above, but limited to a specific subjett. Some SIGs are open to
all users while others are limited to a specified group di users. Security is deter-
mined by the SIC Moderator. Examples of SIGs currently on CLU-IN are:
• Groundwater and Engineering Forums j
• On-Scene Coordinators/Removal Actions |
• Innovative Technologies
How to Log On i
To log onto CLU-IN, you need a computer, a modem, la phone line, and telecom-
munications software (such as CrossTalk™, Procomm1^, or SmartCom™). Set your
communications parameters to 8 data bits, no parity, ahd 1 stop bit. The phone
number is 301 -589-8366. If you have trouble logging on, either through your
modem or through a LAN system or data switch, contact the System Operator
(SYSOP) at 301-589-8368. '
or
The CLU-IN Bulletin Board was formerly known as tpe Office of Solid Waste
and Emergency Response (OSWER) Bulletin Board. [
-------
Bforennedidtion Infernintien in the ATfIC
by Curtis Harlin, Office of Research and Development
W hris Hibberd is a project manager for BIOREM Corporation. BIOREM works in collaboration with the Microbial Biotech-
nology Laboratory at the University of Waterloo to develop and enhance the unique biodegradation capabilities of micro-
organisms for the bioremediation of toxic organic wastes. Chris frequently checks ATTIC for any new information on
bioremediation or related topics. He recently contacted ATTIC to find information on slurry biodegradation and was able to
download many abstracts regarding slurry biodegradation as well as a Superfund Engineering Bulletin. Slurry biodegradation has
been shown to be effective in treating highly contaminated soils and sludges for a wide range of organic contaminants including
pesticides, fuels, creosote, PCP, PCBs, and some halogenated volatile organics. BIOREM maintains a file library of
bioremediation information obtained from ATTIC and other sources for use in its research. Chris also checks the Bioremediation
Special Interest Group on the ATTIC Bulletin Board to keep track of new technologies and ideas. If you would like to access
ATTIC online, dial 301-670-3808 or contact the System Operator at 301-670-6294.
Heavy Metdls in Seiis and Sludfpes Heittoveel with
Plasma Centrifugal Furnciee
by Laurel Staley, Risk Reduction Engineering Laboratory
Hie major components of Retech's process
are the plasma torch, a rotating reactor well, an
afterburner, a secondary combustion chamber
and an off-gas treatment system. Contaminated
soil is placed in a bulk screw feeder and gradu-
ally fed into me rotating reactor well. At Butte,
the soil was fed to the furnace at the rate of ap-
proximately 1:20 pounds per hour. Solid mate-
rial was retained in the tub by centrifugal force
while a plasma arc heated the material to about
3000° F. At this temperature, organic contami-
nation was volatilized from the soil. Any com-
bustible gases remaining after volatilization and
oxidation were incinerated by the afterburner lo-
cated downstream of the reactor well. Atthe
end of the process, the molten mass of treated
solids flowed through the secondary chamber
and into a slag collection chamber.
The exhaust from the furnace is passed
through a gas treatment system that consists of a
quench tank, a venturi scrubber, a packed-bed
scrubber and a demister. A mildly caustic solu-
tion is supplied to the quench tank and scrubbing
unit to help remove acidic gases and particulates
in the off-gas. Moisture droplets entrained in the
flow are removed by the demister. A stack
blower maintains a vacuum on the system and
i he Superfund Innovative Technology
Evaluation (SITE) Demonstration program
recently evaluated Retech, lhc.'s plasma
centrifugal furnace at the Department of
Energy's ComponentDevelopment and In-
tegration Facility in Butte, Montana.
Retech's process is a thermal technology that
uses heat generated by a plasma torch to de-
contaminate soils and sludges containing
heavy metals and organic hazardous com-
pounds by melting metal-bearing solids. In
the process, it thermally destroys organic
contaminants. The molten soil, when
cooled, forms a hard, glass-like non-leach-
able mass. At the demonstration in Butte,
the waste consisted of soil from the Silver
Bow Creek Superfund Site spiked with con-
taminants for the demonstration. Contami-
nants were at or above the following levels:
28,000 parts per million (ppm) zinc oxide
and 1,000 ppm hexachlorobenzene mixed in
a 90/10 weight ratio with No. 2 diesel oil.
The zinc oxide was added as a tracer metal
to determine the teachability of the slag.
Hexachlorobenzene was the Principal Or-
ganic Hazardous Constituent (POHC) used
to determine organic destruction.
Metals and
organics
Plasma
Centrifugal
Furnace
Soil and sludge
draws the
clean gases
into the ex-
haust stack. ^ ""
The destruction and removal efficiency
of the POHC was greater than 99.99% (based
on detection limits) in all of the tests. The so-
lidified treated soil was non-leachable for
both organic and inorganic compounds that
were leachable in the waste feed. A high per-
centage of the metals from the feed soil were
captured and retained in the vitreous slag. An
average of 0.374 grains per dry standard cu-
bic foot (dscf) of paniculate were emitted in
the stack gas throughout the three tests. This
exceeds the Resource Conservation and Re-
covery Act regulatory limit of 0.08 grains/
dscf; so, additional air emission controls
would have to be used. Additionally, NOx
controls may be required.
A Technical Evaluation report and an
Applications Analysis Report describing the
complete demonstration will be available in
the Summer of 1992. For more information
now, call Laurel Staley at the Risk Reduction
Engineering Laboratory on FTS 684-7863 or
513-569-7863.
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New for the
Bookshelf \
Innovative Treatment Technologies: Semi-Annual Sta-
tus Report. Documents the selection and use of innova- i
live treatment in the Superfund program.
Document No. EPA/540/2-91/001 >
I
Fate of Poly chlorinated Biphenyls (PCBs) in Soil Pol- i
lowing Stabilization with Quicklime. Reports on EPA in-
vestigation conducted to verify claims that use of quick- j
lime alone can promote decomposition of PCBs. i
Document No. EPA/600/2-91/052 I
Recent EPA publications are available from
ORD's Center for Environmental Research Infor-
mation (CERI) in Cincinnati. You can order them
electronically on the CLU-IN Bulletin Board or |
directly from CERI. To contact CERI's Publica- i
ttons Unit, call FTS 684-7562 or 513-569-7562. !
You must have the EPA document number or the
exact title to order a document. i
Conference
Alert
Bioremedidtion
Satellite
Semincir
Januarys, 1992
Together with the Hazardous Waste Action Coali-
tion, and in cooperation with EPA, the Department of
Energy, and a number of other professional organi-
zations, the Air and Waste Management Association
is producing a video conference on bioremediation
which will be sent via satellite to more than 80 video
conference sites across the U.S. and Canada. You
can register to attend at a ssite near your office. For
more information, phone Bob Hurley, Air and Waste
Management Association at 412-232-3444.
To order additional copies of this or previous issues of Tech Trends, can the publications unit at CERI
(513) 569-7562 or FTS 684-7562 and refer to the document number on the cover of the Issue,
To be Included on the permanent mailing list for Tech Trends, call 703-308-8800.
st/'£"h-i ^ ,,„ /;
Tech Trends welcomes readers' comments, suggestions for future articles and contributions.
Address correspondence to; Managing Ed!tot?Teeh Trends (O&110W)>
U.S. Environmental.Protection Agency, 401 M Street, S.W., Washington, DC 20460.
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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