United States
Environmental Protection
Agency
Hazardous Waste Engineering
Research Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S2-85/105 Jan. 1986
AEPA Project Summary
Decontamination
Techniques for Mobile
Response Equipment Used at
Waste Sites (State-of-the-Art
Survey)
John P. Meade and William D. Ellis
A state-of-the-art review of facility
and equipment decontamination, con-
tamination assessment, and contami-
nation avoidance has been conducted.
This review, based on an intensive
literature search and a survey of various
equipment manufacturers, provides pre-
liminary background material on the
subject. The information developed here
constitutes an important "head start"
for those who need to establish pre-
ventive measures, decontamination
plans, and procedures for response
personnel and cleanup equipment used
at hazardous waste sites.
The study discusses various decon-
tamination methods, such as use of
solvents to wash off contaminants, use
of chemical means to degrade contam-
inants, and use of physical means to
remove contaminants. Chemical and
physical testing methods designed to
assess the nature of the contaminant
and the quantity and extent of contam-
ination were also investigated. Also
discussed in the full report are proce-
dures that can be used to prevent
contamination of response equipment
and personnel. These preventive pro-
cedures are: enclosures to prevent
spread of contaminants, safety features
on response equipment to prevent spills
and leaks, protective coatings on re-
sponse equipment surfaces, and use of
protective clothing and furnishings for
personnel.
Three case studies were also re-
viewed: The Three Mile Island cleanup.
the "Vulcanus" incinerator ship cleanup
(dioxins and PCBs), and PCB cleanups
in Binghamton, New York. The review
has identified several methods that
could be of value in effectively decon-
taminating response equipment units,
such as a mobile incinerator at a reason-
able cost.
This Project Summary was developed
by EPA's Hazardous Waste Engineering
Research Laboratory. Cincinnati, 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).
Introduction
A state-of-the-art review of facility and
equipment decontamination methods
was conducted by the U.S. Environmental
Protection Agency (EPA) to provide waste
site response personnel with an introduc-
tion into the area of contamination avoid-
ance and decontamination techniques
that may be applicable to mobile response
equipment. The full report, based on an
intensive literature search and a survey
of various equipment manufacturers,
provides preliminary background mater-
ial on the subject. The information pre-
sented constitutes an important "head
start" for those who need to establish
preventive measures, decontamination
plans, and procedures for response per-
sonnel and cleanup equipment at haz-
ardous waste sites.
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Mobile response equipment that was
developed by the Releases Control Branch
of the EPA Hazardous Waste Engineering
Research Laboratory is also in need of
contamination control and decontamina-
tion procedures. The response unit pri-
marily in need of these procedures is the
EPA-developed Mobile Incineration Sys-
tem, which has been used for incinerating
dioxin-contaminated soils. The full report
refers to the decontamination of the
mobile incinerator, while providing in-
formation applicable to other types of
mobile response units.
Decontamination methods generally
rely on fundamental techniques for treat-
ing an assortment of hazardous/unwant-
ed substances. Areas that demand sur-
face decontamination, include:
Nuclear waste activities
Chemical/biochemical warfare agent
cleanup
Chemical process tank cleaning
Drum recycling.
An overview of decontamination methods
relative to these areas is provided in the
full report's introduction, and specific
case examples are also outlined in greater
detail.
The remainder of the report discusses
methods commonly used by chemical
manufacturing industries for reducing or
preventing contamination of equipment
at hazardous waste sites and outlines
methods to quantitatively measure the
levels of contaminants. This helps to
define decontamination procedures and
safety criteria to be used following con-
taminant detection and evaluation. Test
cases where contamination avoidance/
decontamination activities were actually
employed are also described.
Contamination Avoidance
One mode of minimizing exposure
potential to contaminants present at
waste sites is through contamination
avoidance to reduce or prevent contam-
ination of mobile response equipment.
Four methods of contamination avoidance
are discussed in the full report. These
methods appear to be most effective and
economically feasible. The methods in-
clude:
Enclosed structures and secondary
containment for the mobile response
units (e.g. mobile incinerator)
Mobile equipment safety features to
prevent spills and leaks
Protective coatings for the mobile
response equipment
Protective clothing and equipment for
personnel
Assessing Contamination
Levels
After a contaminated area and associ-
ated components are identified, a series
of chemical and/or physical tests are per-
formed to quantitatively measure the
levels of contaminants present in the
subject area. The full report outlines
considerations which must be addressed
when performing surface sampling and
analysis using applicable chemical and
physical tests. In addition, it notes various
difficulties in analyzing for compounds
such as dioxin.
Decontamination of Mobile
Response Equipment
Chemical and physical properties of
hazardous substances in the water or soil
being treated are major considerations in
designing equipment decontamination
procedures. Procedures for decontamina-
tion may be divided into three categories:
Solvent and solubilization methods
Chemical degradation of surface con-
taminants
Physical decontamination methods.
Each procedure utilizes different mech-
anisms for removing contaminants. They
vary with regard to operation efficiency,
safety, cost, and requirements for pre-
treatment and cleanup steps. The full
report provides a comprehensive over-
view of these methods.
Case Studies
Published documen.ation on the fol-
lowing decontamination projects was
assessed to identify techniques poten-
tially applicable to the chemical decon-
tamination of mobile treatment units:
Binghamton State Office Building:
Decontamination of PCBs, dibenzofur-
ans, and dibenzodioxins following a
building fire;
Incinerator Ship M/T "Vu/canus":
Decontamination of 2,3,7,8-TCDD
from ship surfaces and holding tanks
during and following incineration op-
erations;
Three Mile Island Reactor No. 2:
Decontamination of radiation from a
variety of surfaces.
Decontamination methods developed and
tested for these projects include the use
of nonionic detergents, salt water and
acetone rinses, and electropolishing tech-
niques.
Sufficient evidence on the actual ef-
fectiveness of the methods used in these
projects was available only for the Bing-
hamton Office Building decontamination
project. The specific nonionic detergents
which were applied to the building re-
duced the level of PCB, dibenzodioxin,
and dibenzof uran contamination to levels
that were acceptable for human exposure.
Other aspects of these case studies
were also considered. The personnel
protection plans, which were documented
for two of the three cases, indicate that
several approaches for personnel protec-
tion may be implemented. These methods
include isolating contaminated areas,
using disposable protective clothing, and
monitoring work space air and surface
areas to avoid unpredicted exposures.
Conclusions and
Recommendations
The decontamination and contamina-
tion avoidance methods outlined in this
Project Summary, such as the physical
and chemical cleaning methods, protec-
tive coatings, personnel protective cloth-
ing and equipment, and containment
structures, have a wide range of advan-
tages. The following paragraphs present
several promising decontamination sce-
narios, based on combinations of the
methods described in the full report.
Seamless surface coatings of heat and
chemically resistant, durable polymers
will increase the ease and effectiveness
of most decontamination methods that
are used for mobile response units. Also,
the presence of a drainage and collection
system beneath the mobile units to
contain rinses and other surface cleaning
wastes will facilitate the decontamination
process.
Decontamination can be simple. Vacu-
uming can effectively remove gross con-
tamination such as particulates from
coated surfaces. Final decontamination
may then be accomplished using either
detergents and high pressure water or
wet abrasive blasting. Spent wash and
rinse waters may be collected and proper-
ly stored for incineration, or off-site
disposal.
Vacuuming, or an initial water rinse to
remove gross contamination, followed by
the application of a solvent, or acid-based
foam or gel, is another approach. After
allowing time for contaminant solubiliza-
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tion, the formulation may be rinsed off
and collected for disposal. This process
may be repeated to accomplish sufficient
decontamination.
Areas of mobile response units that are
most heavily contaminated, such as the
loading area and hopper system on the
mobile incinerator, may be stripped to
bare metal to ensure the highest level of
decontamination. One of the most prom-
ising techniques is exposure to high
intensity UV light or flash blasting, which
destroys contaminants at temperature
flashes of 2,760°C. Insomecases, heavily
contaminated areas may be disassembled
and cleaned separately via high pressure
FREON* or ultrasonic cleaning.
J. P. Meade and W. D. Ellis are with JRB/SAIC, McLean, VA 22102.
Mary K. Stinson is the EPA Project Officer (see below).
The complete report, entitled "Decontamination Techniques for Mobile Response
Equipment Used at Waste Sites (State-of-the-Art Survey)." (Order No. PB 85-
247 021 /AS; Cost: $11.95, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield. V'A 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Releases Control Branch
Hazardous Waste Engineering Research Laboratory
U.S. Environmental Protection Agency
Edison, NJ 08837
*Mention of trademarks or commercial products does
not constitute endorsement or recommendation for
use by the U S Environmental Protection Agency
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United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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EPA/600/S2-85/105
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