United States
                              Environmental Protection
                              Agency	
     EPA/540/S5-91/006
     September 1991
&EPA
                            SVPERFVND INNOVATIVE
                            TECHNOLOGY EVALUATION
                            Technology   Demonstration
                            Summary

                            Design  and  Development  of  a
                            Pilot-Scale  Debris
                            Decontamination   System
                            M.A. Dosani and M.L. Taylor

                              Metallic, masonry, and other solid
                            debris that may be contaminated with
                            hazardous chemicals  litter numerous
                            hazardous waste sites in the United
                            States.  Pplychlorinated  biphenyls
                            (PCBs), pesticides, lead, or other metals
                            are some of the contaminants of con-
                            cern. In some cases, cleanup standards
                            have been established (e.g., no greater
                            than 10ng PCBs/100 cm2 for surfaces
                            to which humans may be frequently
                            exposed).  If decontaminated, this debris
                            could be returned to the site as "clean"
                            fill or, in the case of metallic debris,
                            sold to a metal smelter.
                              This project involves the develop-
                            ment and demonstration of a technol-
                            ogy intended specifically  for onsite  de-
                            contamination  of debris. Both bench-
                            scale and pilot-scale versions of a  de-
                            bris washing system (DWS) have been
                            designed, constructed, and demon-
                            strated. The DWS entails  application of
                            an aqueous solution during a high-
                            pressure spray cycle,  followed by  tur-
                            bulent wash and rinse cycles. The
                            aqueous cleaning solution is recovered
                            and  reconditioned  for reuse concur-
                            rently with the  debris-cleaning process,
                            which minimizes the quantity of pro-
                            cess water required to clean the  de-
                            bris.
                                This Project Summary was devel-
                            oped by EPA's Risk Reduction Engi-
                            neering  Laboratory, Cincinnati, OH, to
                            announce key findings of the SITE  pro-
                            gram demonstration that is fully docu-
                            mented in a separate report of the same
                            title (see ordering information at back).
Introduction
  Numerous sites  in the United States
are contaminated with  hazardous waste,
and the cleanup of these sites is a top
environmental priority of the decade.  Cur-
rently, more than 1200 sites are included
on the National Priorities List  (NPL), and
many more have been proposed for in-
clusion on the list. A  typical  hazardous
waste site contains toxic organic and/or
inorganic chemical  residues that are fre-
quently  intermingled with remnants of
razed structures (e.g.,  wood,  steel,  con-
crete block, bricks) as well as contaminated
soil, gravel, concrete, and sometimes me-
tallic debris (e.g., machinery  and equip-
ment, transformer casings, and miscella-
neous  scrap  metal). Decontamination of
these materials is important to  prevent the
spread of contamination offsite and to fa-
cilitate  the disposal of the debris in an
environmentally safe  manner. Because
most of the  contaminated debris at
Superfund sites has no potential for re-
use, the purpose of a debris  decontami-
nation system would be to decontaminate
the material sufficiently to permit its return
to the  site as "clean"  fill or to  allow its
disposal in a Subtitle D sanitary landfill or
municipal incinerator rather than a Re-
source Conservation and  Recovery Act
(RCRA) Subtitle C  hazardous  waste land-
fill or incinerator.

Objectives
  The project was  conducted  in two
phases. The objectives of Phase I were:
  . to  evaluate  a hydromechanical
    cleaning system, an  innovative ap-
    proach for decontaminating debris,
                                                                           Printed on Recycled Paper

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   . to conduct bench-scale testing with
     a portable module  for the  decon-
     tamination of debris, and

   . based on bench-scale  results,  to
     develop  a pilot-scale experimental
     debris  decontamination  module
     (EDDM).

  The objectives of Phase II were:
   . to continue development  of  the
     EDDM into a proven technology for
     removing various contaminants from
     debris  found  on  hazardous  waste
     sites,
   . to conduct bench-scale tests to opti-
     mize the process,
   . to design and construct a transport-
     able pilot-scale DWS,
   . to field-test the  pilot-scale DWS at
     two  hazardous  waste  sites  where
     various types of  debris are present,
     and

     to prepare a conceptual design of a
     full-scale DWS.

  This report is presented in two volumes.
Volume  describes the design and devel-
opment of the  Phase  I and II  pilot-scale
debris  decontamination systems and  pre-
sents the results of the decontamination
demonstrations conducted  at three haz-
ardous waste sites.  Volume  II contains
copies of the analytical data submitted by
the various  laboratories  involved  in the
project.

Phase  I: Development and
Testing  of Experimental
Modules
   During Phase I of the project, a  hydro-
mechanical cleaning  system,  an  innova-
tive approach  to decontaminating debris,
was  developed and evaluated.  A bench-
scale,  portable module  consisting of an
enclosure where debris was placed and a
closed-loop  solvent-delivery  system  was
tested. Based  on the bench-scale results,
a  pilot-scale  EDDM was developed  and
field-tested.
  A  300-gal-capacity   pilot-scale   EDDM
was  designed, assembled, installed (on a
48-ft semitrailer), and tested at the Carter
Industrial  Superfund  Site  in Detroit, Ml.
This site  contained large quantities of dif-
ferent types of  PCB-contaminated debris,
including scrap metal, 55-gal metal drums,
tools,  equipment, and  some  furniture items.
  Two 200-lb batches of  metallic debris
were  cleaned  in the system.  Before  and
after treatment, surface-wipe samples were
obtained  to determine  the contaminant re-
moval efficiency  of the system. The per-
centage reduction of PCBs  achieved dur-
ing cleaning  ranged from  33% to 87%
(average reduction of 58%) for Batch  1
and from 66% to 99% (average reduction
of 81%) for Batch 2.
  The  surfactant solution in the  EDDM
was  sampled twice  during the  actual
cleaning process, and PCS concentrations
of 928 and 420  ng/L were  found. Upon
completion  of the  debris-washing  experi-
ment, the cleaning solution was pumped
through  a series of particulate filters and
finally through activated carbon. The PCS
concentration  was reduced  to 5.4 n.g/L
during this  treatment. Most  municipalities
allow water containing a  PCS concentra-
tion  of  <1p.g/L to be sewered, and this
level was achieved by recycling the pro-
cess water through carbon a second time.

Phase  II:   Design, Construction,
and Demonstration  of a Trans-
portable  Debris-Washing
System
   Phase II of this project was directed
toward  further  development of   debris
washing into  a proven technology  for  re-
moving  various contaminants from debris
found on hazardous waste sites in prepa-
ration for full-scale  demonstrations  at
Superfund  and.  other hazardous waste
sites. An initial series of bench-scale tests
were performed in  a controlled environ-
ment to optimize the newlydesigned debris
washing system. After  the  bench-scale
evaluation,  a  transportable pilot-scale ver-
sion of the  DWS was  designed, con-
structed, and demonstrated at actual haz-
ardous waste sites.
   Based on experience gained during the
Carter site field test, a  bench-scale (20
gal of surfactant solution  capacity) debris
washing unit was  designed,  constructed,
and  assembled.  This system consisted  of
a spray tank, wash tank,  oil-water  separa-
tor, and ancillary equipment  (i.e.,  heater,
pumps,  strainers,  metal  tray, etc.). This
bench-scale  DWS was developed to de-
termine  the  ability of the system to  re-
move contaminants  from debris  and to
facilitate selection of the  most  efficient
surfactant solution.
   During these  bench-scale experiments,
surface-wipe  samples of the six pieces  of
control debris were taken before and after
treatment and analyzed for oil and  grease.
Based  on the results, a nonionic surfac-
tant  solution was selected as the solution
best suited for cleaning  oily metal parts
and  debris.
   As part of the continuing  investigation
into  the performance of the DWS, the
representative  pieces of debris were spiked
with  a mixture  of spiking  material  (used
motor oil, grease, topsoil, and sand) con-
taining representative contaminants  (DDT,
lindane, PCBs, and  lead sulfate) and
washed in  the  DWS with the selected
surfactant solution. Three trials were per-
formed. Surface wipe samples  of  debris
from the first two trials were analyzed  for
PCBs,  lindane, and DDT; the surface wipe
samples from the third trial were analyzed
for total lead.
  Table 1  summarizes  the  quantities of
PCBs  and  pesticides on  the surface of
each piece of debris before and after
cleaning (Trial 2). Table 2 summarizes the
quantities of  lead found before  and after
treatment (Trial  3).  The  average  overall
reductions  of PCBs  and  pesticides
achieved  during Trials  1 and 2 were
greater than  99% and 98%,  respectively.
The  overall reduction  of lead was greater
than 98%.
  After completion of the bench-scale de-
bris-washing  experiments,  the  cleaning
solution was  neutralized to a pH of 8 and
then pumped through  a  series of particu-
late  filters  and finally through  activated
carbon. During this treatment, the PCS,
lindane.  and  DDT  concentrations  were
reduced to <2.0, 0.03, and 0.33 ^g/L,  re-
spectively. The concentration of lead was
reduced to 0.2  mg/L after  treatment.

Design, Fabrication,  and
Demonstration  of Pilot-Scale
DWS
   Based on the results  obtained from
bench-scale studies, a  Phase II SOOgal
capacity pilot-scale  DWS was  designed
and  constructed. The process  flow dia-
gram of the pilot-scale system is presented
in Figure 1.
   The pilot-scale DWS was assembled in
a warehouse in Cincinnati, OH, and sev-
eral tests  were conducted.   After  the
warehouse testing,  the  DWS was  disas-
sembled, loaded onto a  48-ft semitrailer,
and  transported to the Gray PCS  site in
Hopkinsville.  KY, which  was selected  for
the field demonstration.  The entire DWS
was reassembled on  a 25-ft x 24-ft con-
crete  pad.  A  temporary  enclosure  (ap-
proximately  25 ft high)  was built  on  the
concrete pad to enclose the DWS  and to
protect the equipment and the  surfactant
solution from rain and cold weather. The
Gray PCS site  contained between 70 and
80 burned out transformer casings  and
other large amounts of  scrap metal.  The
demonstration  took  place in  December
1989,  and  ambient temperatures were at
or below freezing during the entire  opera-
tion.

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Table 1.  Summary of Bench-Scale Results of Controlled Debris Analyzed for PCBs and Pesticides (Trial 2)
Controlled
Debris Contaminant
Lindane
Metal 4.4' DDT
PCB- 1260
Lindane
Metal 4.4' DDT
PCB- 1260
Lindane
Metal 4.4' DDT
PCB- 1260
Lindane
Brick 4.4' DDT
PCB- 1260
Concrete Lindane
Block 4,4' DDT
PCB- 1260
Lindane
Plastic 4.4' DDT
PCB- 1260
. U indicates that the target compound
Pretreatment Posttreatment . Percent Average
fog/WO cm*) fag/lOO cm") Reduction Reduction
11,800
9320
1770
8180
7540
f 780
6750
5840
7450
5870
5660
7220
6440
6670
7390
70,300
8400
7620
was not detected at
Table 2. Summary of Bench-Scale Results of Controlled
Controlled
Debris Contaminant
Metal Lead
Metal Lead
Metal Lead
Brick Lead
Concrete
Block Lead
Pretreatment
fag/1 00 cm *)
876
414
450
508
474
0.73 U
2.32
2.0 u
0.37 u
4.8
2.79
0.41
2.61
2.0 u
3.49
10.5
4.1
397
389
66.7
52
223
35
this level.
Debris Analyzed for Lead (Trial 3)
Posttreatment Percent
(\ig/100 cm *) Reduction
6.0 99.31
6.0 98.55
<3.0 >99.33
<3.0 >99.4 (
<3.0 >99.27
700
99.97
299.89
700
99.94 >99.91,
99.84 for metal
99.99
99.95
>99.86
99.94
99.87 99.80
99.66
93.83
94.11 94.39
95.24
99.49
97.34 98.22
97.84








  Plastic
                        Lead
                                         446
                                                             <3.0
                                                                                >99.33

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                                                                                            •— Sl«p 1 • Sprty Cyd«
                                                                                            •ftfft. sup 2 - W»h Cydt
                                                                                            »•• sup 3. Rinit Cyd«
                                                                                            	 DE F»t«r
                                                                                            • " i W«Ur Traimwd Sltp

                                                                                            Q Pump

                                                                                                Activated Ctrbon
Figure 1. Schematic of Pilot - Scale Debris Washing System.
  Before the cleaning process  began, the
transformer casings (ranging from 5 gal to
100  gal  in size) were cut  in half with  a
metal-cutting partner saw. A pretreatment
sample was obtained from one-half of each
of the  transformer casings  by  a surface-
wipe technique.  The transformer halves
were  placed  into a  basket and lowered
into the spray tank, which was equipped
with  multiple water jets  that blast loosely
adhered  contaminants and dirt from the
casings. After the spray cycle,  the basket
of casings was removed and transferred
to the  wash tank,  where the debris was
washed with a high-turbulence wash.  Each
batch of  debris was  cleaned for a period
of 1  hr in the spray tank and 1 hr in the
wash tank.  During both the  spray  and
wash  cycles, a  portion of the cleaning
solution was cycled through a closed-loop
system in which the oil/PCB-contaminated
cleaning  solution was passed through an
oil/water  separator, and  the cleaned  solu-
tion was  then recycled into the DWS. Af-
ter the wash cycle,  the  basket containing
the casings was returned  to  the  spray
tank, where it was rinsed with fresh water.
  On completion of the  cleaning process,
posttreatment wipe samples were obtained
from each of  the  transformer  pieces to
assess the post-decontamination  PCS
levels.  The average PCS  concentrations
on the internal surfaces of the transformer
casings  before  and  after cleaning are
summarized in Table  3. The before-treat-
ment concentrations ranged from  0.1  to
98 ng/100 cm2. The after-treatment analy-
ses  showed  that  all  the  cleaned trans-
formers had  a  PCS  concentration  lower
than the acceptable level  of  10  ^g/100
cm2.
  After treatment of all the transformers
at the site,  the surfactant solution and the
rinse water were placed in the water treat-
ment system, where  they were  passed
through a series of particulate filters, then
through  an activated-carbon  drum,  and
finally  through an  ion-exchange column.
The before-  and  after-treatment water
samples were collected and analyzed  for
PCBs  and selected  metals  (cadmium,
copper, chromium,  lead,  nickel and  ar-
senic).
  The water treatment system reduced
the   PCS  concentration in the water  to
below  the detection limit.  The  concentra-
tions of  each of the  metals (except  ar-
senic)  were reduced to the allowable dis-
charge levels set by the city of Hopkinsville.
On   receipt of the analytical results, the
treated water was  pumped into a  plastic-
covered 1 0,000-yd3 pile  of contaminated
soil  at the site.
  During this site cleanup, 75 transform-
ers were cleaned in the DWS. All of them
are now considered clean  and acceptable
for  sale to scrap metal dealers or to a
smelter for reuse.

Demonstration at the Shaver's
Farm  Drum  Disposal  Site
  In August 1990, a second demonstra-
tion  of  the DWS was  conducted  at the
Shaver's Farm  drum  disposal  site near
Chickamauga,  GA,  where 55gal  drums
containing varying amounts of a herbicide,
Dicamba  (2-methoxy-3,6 dichlorobenzoic
acid), and benzonitrile (a precursor in  the
manufacture  of Dicamba) were  buried.
EPA Region IV had excavated more than
4000  drums from one location on this  5-
acre  site when this  demonstration  oc-
curred.
  The pilot-scale system was transported
to this site on a 48-ft semitrailer and  as-
sembled on a 25x24 ft concrete pad. The
temporary enclosure used at the Gray site
was reassembled  to  protect  the  equip-
ment from rain. Ambient  temperature  at
the site during  the demonstration ranged
from 75° to 105° F.
  The 55-gal   herbicide-contaminated
drums were cut into  four  sections,  and
pretreatment surface-wipe  samples were

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obtained from  each section.  The  drum
pieces were first placed in the spray tank
of the DWS for 1 hr of surfactant spray-
ing, then  in the wash  tank for an  addi-
tional  hour of  surfactant washing, and  fi-
nally in the spray tank for 30 min of  water
rinsing. The drum  pieces were  then  al-
lowed to air-dry before the posttreatment
surface-wipe  samples  were  taken. Ten
batches of 1 to 2 drums per batch  were
treated during  this demonstration.
  Tables 4 and 5 summarize the surface-
wipe  concentrations of benzonitrile and
Dicamba,  respectively, on the internal sur-
faces  of the drums before and after clean-
ing.   Pretreatment concentrations   of
benzonitrile  in  surface wipe samples
ranged from 8 to 47,000 ng/100cm2 and
averaged 4556 |j.g/100cm2; posttreatment
samples ranged from below detection limit
to 117 m)/100cm2 and  averaged 10 \ig/
100 cm2.  Pretreatment  Dicamba values
ranged from below detection limit to 180
H.g/100cm2 and  averaged 23 ng/1oocm2;
posttreatment concentrations ranged from
below  detection  limit to 5.2 ng/100cmz
and averaged 1  ng/100cm2.
  All site activities described in this docu-
ment were  governed  by EPA-approved
Health and Safety and Quality Assurance
Plans.

Conclusions
  Field-test results obtained with the pilot-
scale DWS in demonstrations at two Re-
gion IV hazardous waste  sites showed
the unit to be both transportable and rug-
ged. Extreme high and  low  temperatures
had little effect  on the operation of the
equipment. The  system successfully  re-
moved PCBs from transformer casing sur-
faces and herbicides and pesticides resi-
dues from drum surfaces.
  The cleaning  solution  was  recovered,
reconditioned, and reused during the ac-
tual  debris-cleaning process;  this  mini-
mized the  quantity  of  process water re-
quired for the decontamination  procedure.
The water treatment system was effective
in reducing contaminant concentrations,
with the exception of arsenic and possibly
Dicamba, to below the  detection limit.
  Planned  progression  of this EPA-devel-
oped  technology includes design,  devel-
opment, and demonstration of a full-scale,
transportable version of the DWS unit.
  The full  report was submitted  in  fulfill-
ment of EPA Contract No. 68-03-3413 by
ITEP,  Inc.,  under the sponsorship  of the
U.S. Environmental  Protection Agency.
                           TABLE 3.     Results Obtained During Field Demonstration of DWS at Gray PCB Site
                                                   Average PCB Concentration of Surfaces fog/lOO cm 'l)

Number

1.
2.
3.
4.
5.
6.
7.
6.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
Before

Average
19.7(1^=10)
9.9 (N=6)
6.6 (N=4)
4.1 (N=6)
4.0 (N=8)
2.0 (N=4)
2.8 (N=2)
23.5 N=5)
8.3 (N=4)
5.2 (N=4)
9.4 (N=4)
48.8 (N=4)
12.3 (N=2)
16.7 (N=2)
18.5 (N=4)
11.3 (N=2)
24.8 (N=4)
8.4 (N=5)
8.3 (N=4)
24.0 (N=3)
18.6 (N=8)
25.0 (N=4)
8.6 (N=4)
6.8 (N=8)
Cleaning

Range
< 0.1-94.0
4.8- 17.0
5.0 - 9.9
<0. 1- 12.0
<0. 1 -28.0
<0.1 - 7.8
1.4 - 4.3
<0. 1 -70.0
2.9 - 23.0
<0.1 - 9.7
<0.1 - 17.0
2.3 - 98.0
9.6 - 15.0
8.7 - 25.0
8.1 - 27.0
8.6 - 14.0
1.1 - 80.0
<0.1 - 19.0
<0.l- 18.0
13.0 - 45.0
<0. 1 - 44.0
12.0 - 35.0
1.5 - 18.0
<0. \ - 31.0
After

Average
1.5 (N=10)
1.5 (N=6)
1.4 (N=4)
0.8 (N=6)
<0. 1(N=8)
2.9 (N=4)
3.9 (N=2)
1.3 (N=5)
3.1 (N=4)
1.9 (N=4)
3.0 (N=4)
1.1 (N=4)
5.1 (N=2)
*01(N=2)

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   Table 4.  Results of Surface Wipe Samples Analyzed for  Benzonitrile, 2,4-Dichlorophenol, 2,  6-Dichlorophenol, and 1,2,4-Trichlorobenzene
          During Field Demonstration of DWS at Shaver's Farm Site (\ig/100cm*)
                         Benzonitrile
                                                      2,4-Dichlorophenol
2,6 Dichlorophenol
1,2,4-Tricholorbenzene
Batch Sample Pre-
Number Number treatment
\

2

3

4

5

6

7

8
9

10

\
2
1
2
1
2
J
2
f
2
1
2
J
2
J
1
2
1
2

180'(50)t
130"(50)
125
90
43
28
4400
2700
4700
2200
10*(5)
8 "(5)
200
320
1400
3000
3500
22*©
1400

Post- Pre-
treatment treatment
ND§
ND
117
7.8"(5)
ND
ND
ND
HO
10* (5)
7.9'(5)
ND
ND
ND
W(5)
28
ND
7'(5)
ND
ND
ND(50)
ND(50)
34
43
ND
ND
NM
HA
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND

ND
ND
ND
ND
16*(5)
14*(5)
NA
NA
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND

Pre-
treatment
ND(50)
ND(50)
ND
ND
ND
ND
NA
NA
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND

Post- Pre-
treatment teatment
ND
ND
ND
ND
ND
ND
NA
NA
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND

ND (50)
ND (50)
ND
ND
ND
ND
NA
NA
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND

Post-
treatment
ND
ND
ND
ND
ND
ND
NA
NA
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND

. Estimated result less than 5 times detection limit.
/ Numbers  in parenthesis indicate the minimum detectable  concentration  of the analyte.
§ None detected in excess of the minimum detectable concentration of 5  \ig/100crr?  unless otherwise specified.
A Not  analyzed.
   Table 5. Results of Surface Wipe Samples Analyzed for Dicamba,  2,4-D, and 2,4,5-7 During Field Demonstration of DWS at Shaver's Farm Site
           fag/I 00cm2)
                                   Dicamba                            2.4-D                                  2,4,5-7
Batch
Number
4

5

6

7

8

9

10

Sample
Number
1
2
1
2
1
2
f
2
1
2
1
2
1
2
Pre-
treatment
1.9
3.4
ND
ND
ND(2.7)
ND(2.7)
7.3*(2.7)
15
55
13
1.7
ND(2.7)
41
180
Post-
treatment
0.63*f0.27)*
ND
ND
2.6
ND
ND(2.7)
1.8
2.3
5.7*(2.7)
0.62*(0.27)
0.63'(0.27)
ND
0.30*(0.27)
0.34*(0.27)
Pre-
treatment
ND§
NM
ND
ND
ND(12)
ND(12)
ND
ND(12)
ND(12)
ND
ND
ND(12)
ND(12)
ND(12)
Post-
treatment
ND
NA
ND
ND
ND
ND( 12)
ND
ND
ND(12)
ND
ND
ND
ND
ND
Pre-
treatment
ND
NA
ND
ND
ND(2.0)
ND(2.0)
ND
ND(2.0)
ND(2.0)
ND
ND
ND(2.0)
ND(2.0)
ND(2.0)
Post-
treatment
ND
NA
ND
ND
ND
ND(2.0)
ND
ND
ND(2.0)
ND
ND
ND
ND
ND
' Estimated result less than 5 times detection limit.
* Numbers in parenthesis indicate  the minimum detectable concentraiton of the analyte.
§ None detected in excess of minimum detectable concentration of\Dicamba at 0.27: 2,4-D at 1.2;  and 2.4.5-7 at 0.20 unless otherwise specified.
A Not analyzed.
                                                                                   6U.S. GOVERNMENT PRINTING OFFICE: 1991 •

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M.A. Dosani and M. L Taylor, are with IT Environmental Programs, Inc., Cincinnati OH
     45246.
 Naomi P. Berkley is the EPA Project Manager (see below).
 The complete report, entitled "Technology Evaluation Report: Design and
     Development of a Pilot-Scale Debris  Decontamination System,"
     consists of two volumes:
 "Volume /"(Order No. PB91-231456AS; Cost: $19.00, subject to change)
     discusses the  development, demonstration, and evaluation of the debris
     decontamination system.
 "Volume II" (Order  No. PB91-231464AS; Cost: $35.00, subject to change)
     contains copies of the analytical data submitted by the various laboratories
     involved in the project.
 Both volumes of this report will be available from:
         National Technical Information Service
         5285 Port Royal Road
         Springfield, VA 22 16 f
         Telephone:  703-487-4650
 The EPA Project Manager can be contacted at:
         Risk Reduction Engineering Laboratory
         U.S.  Environmental Protection Agency
         Cincinnati, OH 45268
United States
Environmental Protection
Agency
Center for Envirnmental Research
Information
Cincinnati, OH 45268
BULK RATE
POSTAGE & FEES PAID
EPA PERMIT NO.  G-35
Official Business
Penalty for Private Use $300

EPA/540/S5-91 /006
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                  JOHN  KING
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                  PARAMUS
    NJ  07652

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