Uoited States
Environmental Protection
Municipal Environmental Research
Cincinnati OH 45268
Research and Development
EPA-600/S2-81-189  Oct. 1981
 Project  Summary
Performance  Testing  of
Four  Skimming  Systems

H. W. Lichte, M. K. Breslin, and G. F. Smith
  A test program (conducted during
the 1979 season) evaluated skimmer
performance in collecting oil floating
on water using several wave condi-
tions,  tow speeds, and skimmer
operating parameters. Performance
tests were conducted at the U.S.
Environmental Protection Agency's
(EPA) Oil  and Hazardous Materials
Simulated  Environmental Test Tank
(OHMSETT) on four commercial oil
spill cleanup devices:  the Sapiens
Sirene* skimming system, the Oil Mop
remote skimmer, the Troil/Destroil
skimming system, and  the Versatile
Environment Products Arctic Skimmer.
  Tests described in this report were
sponsored  by the OHMSETT Inter-
agency Technical Committee (OITC).
The 1979  OITC members were the
Navy-NAVFAC, U.S. Coast Guard,
U.S. Geological Survey, and Envi-
ronment Canada. A 16-mm film "600
Foot Ocean," produced to summarize
the results presented in this report, is
available through the EPA, Office of
Research and Development,  Oil and
Hazardous Materials Spills Branch,
Edison, New Jersey 08837.
  This Project Summary was devel-
oped by EPA's Municipal Environ-
mental Research Laboratory, Cincin-
nati, OH, to announce key findings of
the research project that is fully
documented in a separate report of the
same title (see Project Report ordering
information at back).
'Mention of trade names or commercial products
does not constitute endorsement or recommenda-
tion for use.
  Results and methods used for tests
sponsored by the 1979 OITC are
presented in this report for the following
commercially  available spill  cleanup
equipment: (1 ) Sapiens Sirene Skimming
System, c/o Sapiens, 23-27 Avenue de
Neuilly, F75116 Paris, France; (2) Oil
Mop Remote Skimmer, Oil Mop Pollution
Control, Ltd.,  Toronto, Canada; (3)
Troil/Destroil Skimming System, Hyde
Products, Inc., 810 Sharon Drive,
Cleveland, Ohio 441 45; and (4) Versatile
Environment Products Arctic Skimmer,
60 Riverside Drive,  North Vancouver,
British Columbia, Canada V7H1T4.
  Each system was shipped from  a
foreign country on loan to OHMSETT.
Tests were conducted to evaluate (1)
best oil  collection  performance, (2)
environmental conditions limiting op-
eration, (3) mechanical problems, and
(4) device modifications for improving
performance,  or operating limits, or
  In the full report, quantitative  per-
formance data to support conclusions in
the above areas are presented based on
the  following parameters calculated
from steady state test results.
  (1) Throughput Efficiency (TE) — Per-
    centage of oil entering the skim-
     mer  that  is recovered. This pa-
    rameter is important for advancing
    TE=     Oil recovered
            Oil distributed
            (encounter rate)
  (2) Recovery Efficiency (RE)— Percent-
    age of oil in the fluid recovered by

     the skimmer; applies to all devices
     in this  report and is useful for
     evaluating storage  required to
     contain fluid recovered at a spill.
        RE =    Oil recovered
              Total Fluid

  (3) Oil Recovery Rate (ORR)— Volume
     of oil recovered per unit time; also
     applies to all devices in this report
     and is useful in determining time
     needed  to clean  up a spill of
     known volume.
      DRR=   Volume oil recovered
              Unit of time
  Direct comparison of test  results
should be avoided because all skimmers
were operated differently. The Oil Mop
remote skimmer  and the Versatile
Environment  Products Arctic skimmer
were operated as both stationary and
advancing skimmers, whereasthe other
two were operated as advancing skim-
mers only.

Sapiens Sirene
Skimmer System

Skimmer Description
  The  Sapiens Sirene,  as tested,  is a
two-stage oil skimming system com-
posed of five components (Figure 1). The
first stage is the oil herding section (side
floats); the second is the oil collection
section (rear  float, hoses, and pump).
The five components are:
  (1) a  14.5-m-long float of inflated
     flexible  fabric with an increasing
     boom draft from the forward to aft
     (right side or wing section);
  (2) a 7.5-m-long oil inlet section that
     includes the  narrowing funnel
     leading  into the suction box with a
     torpedo-like float  supporting the
     oil/water inlet in the center;
  (3) another 14.5-m long float of
     inflated flexible fabric with the
     boom draft increasing from for-
     ward to aft end (left side or wing
  (4) an aluminum suction box, with
     floats, that is clamped onto the
     upper part of the apex of the rear
     funnel to accept oil collected; and
  (5) 20 m of  110-mm hose and two air
     driven,  double-acting diaphragm
     pumps  (162  mVhr  capacity) to
     remove  the collected fluid from
     the Sirene  to the collection
  From July 9-20,1979,43 oil recovery
performance tests were conducted with
the Sapiens Sirene skimmer (Figure 1);
31 tests with a high viscosity oil and 12
with a medium viscosity oil.

Best Performance—
  Consistently,  the highest values of
RE, TE.and ORR were obtained during
tow tests with waves. This result was
surprising since waves generally cause
poorer performance in oil skimmers.
  The tests in high viscosity oil produced
better results than the tests in medium
viscosity oil. Medium viscosity oil was
entrained and  lost from the system
more easily than the high viscosity oil
because of interfacial shear forces.
  The best skimmer performance data
(highest numerical results) are presented
along with accompanying test conditions
in Table 1. Because of the skimmer's
operating principle, the highest values
of TE, ORR, and RE did not occur under
the same  test  conditions. Test  oil
logistics prevented using enough oil to
saturate the system over the entire tow
test, thus absolute maximums for ORR
and RE were not determined.
  No oil was lost  because of wave
splashover. The cylindrical design of the
continuous flotation elements caused
the oil and water to be  splashed
forward, in front of the boom; this was
true even at the highest tow speed run
in the roughest wave condition. Another
reason  for lack of splashover was  the
virtual absence of device heave relative
to  the  water's  surface. The great
amount of flotation coupled with  the
concave skirt  design, which  tends to
hold the device to the water's surface,
acted to maintain  a  relatively large,
constant freeboard.
Operating Limits—
  Based on quantitative and qualitative
test results, the operating limits of the
Sirene skimmer  appear to depend on
the following three items:
  (1) Oil  entrainment phenomena at
     tow speeds above 0.75 knot cause
     oil to escape the skimmer before it
     can be pumped out. Such losses
     occurred (1) beneath the points of
     attachment between the side sec-
     tions and the rear collection sec-
     tion, (2)  beneath the large floats
     on  either side of  the  oil/water
     inlet, and (3) out the water outlet
     located beneath the oil suction
     box in  the aft end of the device.
  (2) Limited pump capacity  allows oil
     to build up in front of the oil inlet
     and,  therefore,  is subject to
     entrainment and  shedding be-
     cause  of water flow beneath the
  (3) Oil  cannot  flow easily  to the oil
     suction box  after it enters the oil
     inlet. This allows the oil slick to be
     subjected to water passing below
     it for a longer period of time, thus
     increasing shedding and entrain-
     ment of oil droplets.
  The pumping system did not severely
emulsify  the collected  oil and water.
This  is evidenced  by the  similarity
between the recovery efficiency samples
obtained by allowing gravity to separate
the oil and water and those obtained by
centrifuging  oil/water samples.
  TE was not affected by slick thickness
whereas RE and ORR were directly

Device Modifications—
  Device modifications recommended
for improving  the performance of the
Sapiens Sirene system are:
Table 1.    Best Performance - Sapiens Sirene (High and Low Viscosity Oil).
High Viscosity—
Low Viscosity —


39.7 m3/hr

39.8 m3/hr




(m x m)

0.6 HC
0.6 HC

All waves
0.7 HC



36, 40.


 Oil Suction Hose
        and floats
Floats and
Fabric Funnel
(second stage)
Rear float (second
                                                                             Port Side Float (first stage)
                                                                  Variable Depth Skirt
                                                                           Adjustable Skirt
                                                                           Ballast Chain
                                                                        Direction of Tow
Starboard Side Float
(first stage)
 Figure  1.    Sapiens Sirene skimming system.
   (1) Extend the oil inlet  across the
      entire rear section of the device.
      Eliminate the floats on either side
      of the oil inlet or place outside the
      side  flotation  elements. The oil
      would travel directly from the side
      sections into the narrowing funnel
      behind the oil inlet,  thus elimi-
      nating  the severe angle change
      that developed at the point where
      the  side  sections join  the  rear
   (2) Improve the  narrowing funnel
      behind the oil  inlet to allow oil to
      move more easily through it to the
      oil  suction box.  If oil could be
      transported through  the funnel
      area  at the same flow rate as the
      encounter rate, there would be no
      pool  of oil to be subjected to the
      interfacial shearing forces of the
      water passing beneath  the  pool
      and out the water exit. Longitudi-
      nally arranged flotation elements
      spaced across the funnel would
      allow oil to pass easily by keeping
                            the fabric above the slick's sur-
                         (3) Increase the system pumping
                            capacity by improving  the ar-
                            rangement of the two  double-
                            acting diaphragm pumps used to
                            transfer the oil/water fluid from
                            the suction box to the collection
                            barrels. The pumps would be 12%
                            more  efficient if used indepen-
                            dently of each other rather than in
                            a common  inlet, common  outlet
                            arrangement.  A  doubling  of
                            present  pump capacity is recom-
                         (4) Replace  the center torpedo float
                            on the oil/water inlet with two
                            floats, spaced  at  one-third and
                            two-thirds the distance acros»the
                            mouth, to eliminate turbulence
                            generated  by the float  directly
                            upstream of the oil suction box.
                         If the recommended modifications or
                       ones that serve the same purpose are
                       incorporated into the system,  another
                       test program  should be  performed at
 OHMSETT. The system shows promise
 through  its innovations in design and
 material  use.

 Oil Mop  Remote Skimmer

 Skimmer Description
  The Oil Mop remote skimmer model
 (Figure 2)  was fabricated by Oil Mop
 Pollution Control, Ltd., Toronto, Canada,
 as a preliminary model of a full-size unit
 to be used for Arctic oil spill recovery
 service. The skimmer is designed as an
 unmanned unit controlled by an umbili-
 cal electric cable. The operating principle
 is that of oil slick sorption onto a bank of
 polypropylene rope mops, rotating in the
 vertical plane to produce zero velocity
 relative  to the  surface of the water
 during forward motion of the skimmer.
  From August 6-10,  1979, 19  oil
pickup performance tests were con-
ducted with the Oil Mop remote skimmer:

                    Sump Pump
                                                                                   Sump Pump
                              Dirve Rollers
                       Foam-Filled Hulls
                                                                                              Fixed Prop
                                                          Plywood Bulkhead Added for Test,
                       Drive Rollers
Figure 2.     Oil Mop remote skimmer.
6 with high viscosity o\\ and 13 with
medium viscosity oil.
  The  primary  test  objective was to
generate design information for future
construction of a larger version to be
built -for Arctic service  in Canadian
waters. The following test conclusions
relate to the design criteria for the larger
  (1) At  least three powered rollers
     must be provided to  prevent
     slippage of the oil mop, especially
     when saturated with high viscosity
  (2) The mop-to-oil slick contact length
     and rotational mop speed of the
     full-scale skimmer  should be
     selected after conducting a series
     of oil-mop saturation tests with
     the various viscosity oils expected
   to be encountered. The oil-mop
   saturation times can be compared
   with various values of skimmer
   length divided by mop  speed.
   Sufficient time was not available
   during the  single  test week to
   determine  mop-oil saturation
   time for the two test oils. In tests
   with oils of 185  cSt viscosity,
   however, ORR was unaffected by
   reducing the mop-to-oil  slick
   contact length from 1.9 m to 1.2
   m. ORR performance did fall  off
   rapidly, however, when the con-
   tact length was reduced to 0.6 m.
(3) To maximize oil recovery rate, the
   full-scale  skimmer  hulls  should
   be open on the sides, if possible,
   to allow oil to enter from the sides
   as well  as  the  front.  This will
     increase the  ORR by allowing
     more oil to come in contact with
     the tops of the oil mops floating
     above the water surface.  The
     skimmer  beam should be maxi-
     mized to  increase the oil-mop
     surface area being laid down on
     top of the slick  as it  enters the
     front of the skimmer.
  (4) A positive displacement type off-
     loading pump is necessary to
     ensure rapid  offloading  of  col-
     lected oil over  a wide oil viscosity

Best Performance—
  The objective of these tests was to
obtain design information for a larger
unmanned Oil Mop remote oil skimmed

The highest numerical results obtained
in these tests may not be the maximum
obtainable with the full-scale Oil Mop
skimmer. The highest numerical values
of the three performance parameters of
TE,  RE,  and  ORR for the present
OHMSETT tests are summarized in
Table 2.

Operating Limits—
   Based  on numerical and qualitative
test results, the operating limits for this
skimmer  appear to depend  on  two
factors: (1) oil mop-to-oil slick contact
area and (2) slippage of oil-soaked mops
through the squeezing roller assembly.
   First factor.  During stationary tests
with medium viscosity oil, areas of clear
water appeared under the point where
the oil soaked mops were lifted out of
the water at the stern of the skimmer.
This indicated that the mops, at least on
the side facing the oil slick, were fully
saturated  with test  oil. The ORR
performance increased when the entire
skimmer hulls were lifted clear of the
water  by an overhead crane, thereby
exposing the tops of the floating oil mop
to splashing contact  with oil from the
sides. In the full-scale device, the ORR
can  be increased  by maximizing the
skimmer beam and opening the skimmer
hulls along the length of the skimmer to
allow oil to splash onto the mops from
the sides.
   Second factor. It  is essential that
future skimmers include three powered
rollers instead of two as in the present
Oil Mop  remote unit. Two rollers are
needed to squeeze oil from the saturated
rope  mop. A  third  roller,  operating
against one of the other two rollers, is
needed to provide the mop tension to
maintain the oil mop rotational speed.
By visual observation, in almost all tests
with high viscosity oil and in some with
medium viscosity oil, slippage of the
mops occurred at  the two  squeezing
rollers. This  resulted  in the  mops
remaining on the oil slick after they had
become fully saturated, reducing  the
net oil pickup per unit time.

Troil/Destroil Skimmer System

Skimmer Description
  The  Troil/Destroil  skimmer system
assembled for  OHMSETT testing com-
bined the Troilboom Giant 1.5-m boom
manufactured byTrelleborg AB, Sweden,
and the Destroil Model DS210 skimmer
pump  manufactured  by DESMI A/S,
Table 2.    Best Results - OMI Remote (High and Medium Viscosity Oil).
High Viscosity —
Medium Viscosity —

2.6 m3/hr

2.7 rtf/hr


(m x ml

0.3 x 4.2

0.3 x 4.2
0.2 x 7.0


  The Troilboom consisted of four 6.4-m
sections of a 1.5-m-high  collection
boom (Figure 3). At the center of the
boom is a 3.5-m-wide opening with an
additional section of boom attached that
provides a pocket to collect the swept oil
and contain the floating skimmer pump.
The  boom panels are supported by
curved fiber glass battens that provide a
concave boom profile while under tow.
The boom is towed by an independent
external load line that connects to the
battens  by individual bridles.  This
arrangement allows each boom section
to conform to waves and maintain a
nearly constant waterline.
  The Destroil skimmer pump (Figure 4)
is a  hydraulically-driven screw pump.
Oil is recovered as it flows over the
central  hopper weir  into the  exposed
pump  screw. Skimmer  flotation is
provided by two fixed-position floats and
one that is adjusted by remote ballasting
with compressed air. The pump is driven
by a remote diesel-hydraulic powerpack
that  provides pump power  and air
ballast control.  The pump discharges
through a  127-mm, flexible discharge
hose.  The  screw  and hopper have a
macerator  cutting  edge for chopping
debris that may enter the pump with the

  The Troil/Destroil  skimmer system
was tested at OHMSETT August 15-24,
1979. The tests were conducted to
measure the  recovery performance of
the combined boom and  skimmer
system and observe the interaction of
the boom and floating skimmer.

Best Performance—
  Table 3  shows the  best skimmer
performance for high  and low viscosity
oils. The skimmer performance param-
eters RE and ORR were at their highest
when the boom preload oil volume was
at the test maximum. Because of  the
high skimmer pump capacity,  it was
necessary to change the preload charge
volume. Tests  were conducted with
various boomed preload volumes to
determine performance changes and
guidance for operator control.

Operating Limits—
  The  Troil/Destroil skimmer system,
as tested,  has the following operating
  (1) The  maximum towing speed at
     which the Troilboom can retain
     collected oil,  without significant
     loss, is 1 knot.
  (2) The  maximum pumping rate of
     the  Destroil  skimmer  pump is
     approximately 37.4 mVhr.
  At a boom towing speed of 1 knot, the
Troilboom  lost oil at a rate of approxi-
mately 2.3  mVhr. when the  towing
speed was increased to 1.25 knots, the
oil loss rate increased to approximately
23 mVhr. Oil losses were consistently
observed to be the  result of vortex
shedding occurring near the side walls
of the skimmer collection pocket.
  The Destroil skimmer has an advanc-
ing screw pump that increases pumping
rate  as the viscosity  of the pumped
mixture increases.  The maximum vis-
cosity of the test oil was approximately
925 cSt.
  The test series did not determine the
pumping  capabilities of the  skimmer
with higher viscosity  mixtures. The
skimmer pump was capable of ingesting
a quantity of floating debris deposited
during one of the test  runs. The boom
and skimmer  system  showed good
wave-following in test waves up to 0.47
m harbor chop. The independent towing
bridle allowed the boom to maintain a
relatively constant  waterline  while in
the wave.

                                     Bridle Lines
                                                                        Boom Panels
                                                   Fiberglass Battens
Figure 3.     Troilboom illustration.
                            Remotely Adjustable Air Ballast Float

Mechanically Adjustable Floats (3 positions)
                                                            Pump Discharge
Figure 4.    Destroil skimmer pump.

  The Troil/Destroil skimmer system,
as tested, should be used at speeds not
exceeding 1 knot.  The device can be
used in moderate waves without signifi-
cant performance reduction.  Once
rigged, a single operator can control the
recovery operation by adjusting pumping
rate and skimmer height.  Skimmer
performance for RE and ORR can be
increased  if the operator  allows a
precharge oil volume to remain  in the
skimmer pocket while operating the
pump. At least  3.8 m3 is necessary to
provide an appropriate precharge volume
in the boom pocket for good performance.
  The ORR of the skimmer is limited by
the pump capacity.  A larger pump with
about three times the pumping capacity
should be  considered for the Troil/
Destroil skimmer system. The boom and
skimmer must  be able  to survive a
variety of weather and towing condi-
tions. Towing bridles and boom stiffener
battens should be made stronger so that
the  boom can survive greater towing
loads. The bridle  attachment points
should  be  redesigned to  provide for
quick rigging adjustments  to allow a
proper boom towing attitude.

Versatile  Environment
Products Arctic Skimmer

Skimmer Description
  The Versatile  Environment  Products
Arctic Skimmer (Figure 5) is a  non-self-
propelled advancing weir skimmer with
an adsorbent rotating belt. The skimmer
is equipped with a hydraulic power pack
that powers the collection belt mecha-
nism, the oil offloading pump, and a
water pump for ballasting and powering
the water jet booms. The skimmer can
be operated with the power  pack and
control station onboard the skimmer, or
with  the power pack removed, the
skimmer can be remotely controlled by
means  of a 27.4-m  umbilical hose

  The Versatile  Environment  Products
Arctic Skimmer was tested at OHMSETT
October 15-23,  1979. This  skimmer is
an air-transportable, remotely controlled
version  incorporating the  original
Bennett  oil collection principle. The
Arctic Skimmer  is a prototype version
developed for Environment Canada and
intended for cold-weather use.
  The objectives of the Arctic  Skimmer
 ssts were to observe the  operator
TableS.    Peak Performance - Troil/Destroil Skimmer System (High and Low
           Viscosity OH).
(m x m)
 High Viscosity—

 Low Viscosity—
20.9 m3/hr

23.7 m3/hr



Figure 5.    Versatile Environment Products Arctic skimmer as tested at OHMSETT.
control and mechanical performance.
Skimmer performance was measured
over several tank test conditions to gain
operator control experience that would
maximize skimmer performance,  and
the following conclusions  were deter-
mined from the test series:
  (1) The skimmer can be controlled
     from either onboard with the
     power  pack  mounted  on the
     skimmer  or remotely  with the
     power pack removed and con-
     nected  to  the skimmer through
     the hydraulic control lines.  The
     several adjustable skimmer
     settings can be preset for remote
     skimmer operation.
  (2) The water jet nozzles can effec-
     tively concentrate and sweep oil
     into the skimmer at speeds from 1
                        knot to 4 knots in both calm and
                        wave conditions.
                     (3) The settings of the three adjustable
                        skimmer doors  are critical for
                        maximum  performance at each
                        speed. A graph of  skimmer door
                        settings was developed from
                        performance tests.

                   Best Performance—
                     Table  4  lists the  best  skimmer
                   performance for high and low viscosity
                   oils. In addition to regular towing tests
                   with a 3-mm slick, several tests were
                   performed to establish the maximum
                   ORR of the skimmer. In these tests, at
                   least 25.0-mm thickness of oil  was
                   presented  to  the  skimmer and the
                   skimmer then adjusted  for maximum
                   recovery rate.
                                                                            S. GOVERNMENT PRINTING OFFICE:1981--559-092/3312

    Operating Limits—
      Each of the performance parameters
    can be maximized by the  operator as
    1. To maintain high throughput effi-
       ciency,  the skimmer  should  be
       operated at speeds not greater than
       2 kt. The maximum  safe skimming
       speed in calm water is 5 kt.
    2. To maintain high recovery efficiency,
       a thick oil layer should be maintained
       at the collection belt. The belt should
       be raised to be even with the oil/
       water interface.
    3. The oil recovery rate  of the skimmer
       is limited by the maximum pumping
       rate of the skimmer pump. The actual
       rate will vary with the viscosity and
       discharge hose requirements. Maxi-
       mum pumping rates observed for the
       8-mm discharge hose  with 4.5-m
       head was 23.6 m3/hr.
      The  Arctic skimmer  was tested in
    waves 0.18-m high by 9.4-m long. The
    maximum height of wave in which the
    skimmer can perform  is about 0.3-m
    height, which is about the maximum
    depth of the bow door. As the skimmer is
    able to respond to longer period waves,
    the actual height of  the wave can
    increase if the relative  wave height at
    the skimmer mouth remains nearO.3 m.

      (1) The Arctic skimmer is intended to
         be transported partially disassem-
         bled.  The skimmer  could arrive
         with the belt mechanism removed
         and lowered, flotation collars
         removed,  and  additional  equip-
         ment stored within the skimmer.
         Clear rigging,  reassembly, and
         system check-out  procedures
         should be fixed on the skimmer to
         facilitate quick deployment.
      (2) The skimmer operating manual
         should be  updated to include
        Table 4.    Peak Performance  -  Versatile Environment Products Arctic Skimmer
                   (High and Low Viscosity Oil).
                                               Tow         Waves           Slick
          Performance          Highest         Speed         H x L           Thk.
           Parameter            Value          (kt)         (m x m)          (mm)
High Viscosity—
Low Viscosity—

20 m3/hr

19.4 m3/hr






              optimal skimmer door settings,
              belt speed,  and pump  control
              calibration curves.
           (3) An  auxiliary  cooler  should be
              provided for the hydraulic reservoir
              for extended operation in warm
           (4) The rigging  for  the water jet
              sweep booms should be simplified
              to allow quick adjustment from
              the skimmer.
           (5) The squeeze belt collection sump
              could be enlarged to contain belt
              splashover at high speed.
  (6) The adjustment screws for the aft
     and middle gill door should be
     modified to make readjustment
  The full report was submitted in ful-
fillment of Contract No. 68-03-2642 by
Mason & Hanger-Silas Mason Co., Inc.,
Leonardo, New Jersey 07737, under
the sponsorship  of  the U.S. Environ-
mental  Protection  Agency. Technical
direction and evaluation of the Oil Mop
Remote  skimmer  and the  Versatile
Environment Products Arctic Skimmer
were subcontracted to PA Engineering,
Corte Madera, California.
           H.  W. Lichte. M. K. Breslin, and G. F. Smith are with Mason & Hanger-Silas
             Mason Co., Inc., Leonardo, NJ 07737; D. J. Graham andR. W. Urban are with
             PA Engineering, Corte Madera, CA 94925.
           Richard A. Griffiths is the EPA Project Officer (see below).
           The complete report, entitled "Performance Testing of Four Skimming Systems,"
               (Order No. PB 82-101 353; Cost $9.50, subject to  change) will be available
             only from:
                   National Technical Information Service
                   5285 Port Royal Road
                   Springfield, VA 22161
                   Telephone: 703-487-4650
           The EPA Project Officer can be contacted at:
                   Oil and Hazardous Materials Spills Branch
                   Municipal Environmental Research Laboratory—Cincinnati
                   U.S. Environmental Protection Agency
                   Edison, NJ 08837
United States
Environmental Protection
Center for Erwironmenta) Research
Cincinnati OH 45268
                Postage and
                Fees Paid
                EPA 335
Official Business
Penalty for Private Use $300

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