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OCR for page 34
Worker Protection and Potential for Offsite Release
The recovered chemical warfare materiel at the Pine Bluff
Non-Stockpile Facility (PBNSF) varies more widely in type,
agent content, and physical condition than do the stockpile
items at the same location. Many of the non-stockpile muni-
tions stored at the Pine Bluff Arsenal (PBA) were recovered
from burning pits and are badly corroded and difficult to
characterize. This chapter addresses the unusual challenges
presented by the handling of recovered chemical warfare
materiel, explosively or nonexplosively configured, intended
for PBNSF. It will not review nonmunition safety concerns,
such as conventional industrial accidents and fires not
involving either agent or high explosives.
PROTECTING PINE BLUFF NON-STOCKPILE FACILITY
PERSONNEL FROM EXPOSURE TO CHEMICAL
WARFARE AGENTS
PBNSF personnel will be protected from exposure to non-
stockpile agents by personal protective equipment (PPE), by
barriers, and by engineering controls. The PBNSF process
areas are categorized by hazard type, and personnel are
required to wear different levels of PPE depending on the
hazard category of the process area in which they are work-
ing. The allowable concentration of agent in the air in a given
area determines the type of PPE required. The air in areas
requiring Level A PPE is monitored for agent at the gross
detection level (GDL) or the maximum permissible limit
(MPL). These areas are usually monitored to the GDL
(0.2 mg/m3) but must be below the MPL (100 mg/m3) for
H/HD and HN-3 (U.S. Army, 2003a). The air in the agent-
free areas is monitored at the 8-hour time-weighted average
(TWA) level.) The TWA monitoring level for H/HD and
iTWA is the permissible 8-hour airborne concentration of a chemical
agent to which a worker may be exposed. A IWA exposure limit is gener-
ally set so that workers may be exposed 5 days per week for a working
lifetime with minimal risk of adverse health effects.
34
HN-3 is 0.003 mg/m3. The agent-free areas are monitored
24 hours a day, 7 days a week, to assure a safe working
environment.
Pine Bluff Non-Stockpile Facility Personal Protective
Equipment and Characterization of Process Area Hazards
PBNSF operating personnel entering known or poten-
tially agent-contaminated areas (i.e., hazard Categories A
and B) will use an industrial Level A zipper-type PPE suit.2
These suits are totally encapsulating (vapor-tight) chemical
protective suits with positive pressure, full facepiece, self-
contained breathing apparatus and have been approved by
the National Institute for Occupational Safety and Health
(U.S. Army, 2002a).
Hazard Category A and B areas are under negative air
pressure; Category A areas may be contaminated with liquid
agent and are assumed to be contaminated with agent vapor;
Category B areas may be contaminated with agent vapor.
Further details concerning hazard categories, as well as the
hazard categories assigned to the various process areas of
PBNSF, are provided in Table 3-1.
Pine Bluff Non-Stockpile Facility Chemical Agent
Monitoring Devices
The agents to be monitored are
· sulfur mustard (H. HS, and HD)
· nitrogen mustard (HN-3)
· arsenicals (PD)
2Vivian Graham, Non-Stockpile Chemical Materiel Product, "Pine Bluff
Non-Stockpile Facility Discussion: Safety Issues," briefing to the commit-
tee on April 22, 2003.
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WORKER PROTECTION AND POTENTIAL FOR OFFSITE RELEASE
The air monitoring equipment being considered for
PBNSF includes:
· MINICAMS3 with halogen-specific detectors for
mustard-containing chemical agents
Depot Area Air Monitoring System (DAAMS) moni-
tors (for chemical agents)
· MINICAMS adapted for detection of PD
(phenyldichloroarsine) when processing GTRs filled
with arsenicals
.
The MINICAMS and the DAAMS will be used to moni-
tor for chemical agents at the TWA level throughout the
facility. The MINICAMS is also used to monitor for agents
at the GDL and MPL levels. The DAAMS is frequently used
for perimeter monitoring at facilities, but it is unclear
whether perimeter monitoring will be conducted.
Category A areas at PBNSF are designed to contain po-
tentially high concentrations of airborne agent vapor. Per-
sonnel are required to wear Level A protective gear in all
areas where concentrations could approach levels greater
than the immediately dangerous to life and healths level if
there is an accident. This approach protects workers from
doses that could lead to acute effects.
MINICAMS
The MINICAMS is considered a near-real-time auto-
mated air sampling system with response times that are typi-
cally 4 min for the GDL or MPL levels and 10 min for the
TWA level. The MINICAMS captures the agents on sor-
bent; the agents are then desorbed into a gas chromatograph.
The MINICAMS is configured with a halogen-specific de-
tector (the primary chemicals anticipated are H/HD, MN-3,
and industrial arsenicals, most of which contain the halogen
chlorine). The accuracy of the proposed MINICAMS-XSD
(halogen-specific detector) units is around the TWA level.
When operating in an atmosphere containing a lower con-
centration of agent (<10 TWA), the air is sampled directly
onto a solid sorbent sample tube. In environments with
higher concentrations of agent (>10 TWA), the flow auto-
matically switches to a low volume sample loop before the
3MINICAMS is a low-level, near-real-time monitor typically used to
provide early warning of airborne exposure hazards. The MINICAMS-XSD
(halogen-specific detector) unit is an automated air sampling system that
collects compounds, thermally desorbs them into a capillary gas-chroma-
tography column for separation, and detects the compounds with a halogen-
specific detector (U.S. Army, 2000). The combined sampling and analysis
time for the MINICAMS is 3 to 10 minutes, depending on the agent being
examined (U.S. Army, 2003a).
4Immediately dangerous to life and health is the maximum exposure
concentration from which an individual could escape within 30 min without
experiencing escape-impairing symptoms or irreversible health effects.
35
TABLE 3-1 Hazard Categorization of PBNSF Process
Areas
Process Area
Hazard Categorya
Receiving storage area (includes warming area)
Unpack area
Fill extraction preparation area
Fill extraction area
Detonation chamber area
Decontamination area
Holding tank area
Agent treatment area
Metal parts repackaging and storage area
D
C
A/B
A
A/B
A
A
A, B. C
C/D
aHazard categories are defined as follows: A identifies a toxic process
area under negative pressure, possibly contaminated with liquid agent and
assumed to be contaminated with agent vapor. It is a high-hazard area,
requiring the use of PPE. B indicates a toxic process area under negative
pressure, possibly contaminated with vapor chemical warfare agent. It is a
high hazard area requiring the use of PPE. C indicates work areas under
negative pressure and subject to inadvertent chemical warfare agent vapor
contamination. It is considered a low agent hazard area; protective gear is
not required to be worn unless monitoring indicates a need. Although chemi-
cal warfare agent contamination of Category C areas is not expected, PPE
must be available for use in Category C areas. D indicates areas under
ambient pressure that are not subject to contamination. It is considered a
negligible chemical warfare agent hazard area. These areas are typically
mechanical and electrical equipment support rooms and the facility
perimeter.
SOURCE: Adapted from U.S. Army (2002d).
solid sorbent tube to allow monitoring at higher levels
(MPL).
Depot Area Air Monitoring System Monitors
In the event of a TWA MINICAMS alarm, the DAAMS
is used to confirm the MINICAMS reading. The samples
will be collected using a vacuum pump, a sequencer, and
DAAMS sample tubes. The DAAMS sample tubes are
packed with solid sorbent to trap the airborne chemicals and
will be taken to the laboratory for analysis. DAAMS moni-
toring is also used for analysis of the air lines of the life
support systems to assure personnel they are agent free and
for historical monitoring at DAAMS-only sample stations in
Category D work areas. The DAAMS monitor is based on
solid sorbent preconcentration of the sampled air, followed
by thermal desorption and analysis by gas chromatography
using a flame photometric detector. Sample vapors are
passed directly into the sorbent tube. The preconcentrator
tubes are inserted into a heated inlet, where the contents are
desorbed into a gas chromatograph. A sulfur band-pass filter
and linearizer circuit are used to detect chemical agent.
Knowing the amount of chemical agent on the sorbent tube
and the total volume of air sampled, the average agent con-
OCR for page 34
36
centration in the air can be calculated. By increasing the
sample time or flow rate, the average concentration sensitiv-
ity can be increased. The DAAMS is much more sensitive,
and therefore more accurate, than the MINICAMS method
(the sensitivity of the DAAMS monitors is <0.0006 mg/m3~;
however, the response time is 1 to 12 hours.5
Arsenicals Monitoring
The Army plans to use MINICAMS adapted for detection
of phenyldichloroarsine (PD) for air monitoring when pro-
cessing German Traktor rockets (GTRs) filled with arseni-
cals (U.S. Army, 2003c). PD is the only arsenical to be con-
tinuously monitored because it is the only one with
significant vapor pressure and blistering properties. Other
industrial arsenicals either have very low vapor pressures or
lack vesicant properties.
Monitoring of airborne arsenic for historical purposes will
be carried out by drawing ambient air through filters that
will collect PD and the less volatile arsenical agents as well
as arsenic-containing particulates (U.S. Army, 2003a). Af-
ter sampling, the filters will be digested to convert the ar-
senic-containing materials into an aqueous solution. The
arsenic content of the solution will be determined by con-
ventional means such as atomic absorption spectroscopy or
inductively coupled plasma analysis (U.S. Army, 2003a).
PROTECTION OF PINE BLUFF NON-STOCKPILE
FACILITY PERSONNEL FROM ACCIDENTAL
DETONATIONS
PBNSF must be designed to withstand the accidental
detonation of a munition undergoing treatment while mini-
mizing the release of toxic chemical agents to the atmo-
sphere. Adequately withstanding accidental detonations will
be defined in terms of the explosion containment require-
ments of the individual areas at PBNSF where accidental
detonations could occur (Chapter 2~.
Munitions in specially designed overpack containers are
brought from the storage igloos to the PBNSF receiving dock
and then into PBNSF at the receiving/storage areas, where
they will be warmed during cold weather. After warming,
the overpacked munitions are moved to the unpack room,
where they are checked for leaking agent. Leakers will be
kept in their overpack and returned to storage for treatment
at the end of the destruction campaign for the agent being
processed. Nonleakers are removed from the overpack,
marked as either explosively or nonexplosively configured,
and transferred to the fill extraction preparation area.
In the fill extraction area, munitions are emptied either in
an explosive containment chamber (ECC) or by the projec-
5A variance in response time can be due to the use of different analytical
techniques and/or different sampling times.
lions:
ASSESSMENT OF THE ARMY PLAN FOR THE PINE BLUFF NON-STOCKPILE FACILITY
tile washout system (PWS), depending on whether or not
they are explosively configured. After draining the agent and
washing out the munition in the ECC or PWS, the munition
may be placed in a heel-dissolving tank before being placed
in the detonation chamber (DET), where shaped explosive
charges are used to access and detonate emptied munitions
that are explosively configured.
Accidental detonations are possible at the following loca-
· Receiving dock. This area is the outer entry point for
munitions coming from the storage igloos and is out-
side of the designed containment of PBNSF. There-
fore, the receiving dock could be the site of the most
significant dispersion of agent from an accidental deto-
nation. However, munitions brought to the receiving
dock will be overpacked in containers that are spe-
cially designed to contain leaks from the munitions
within, which will reduce the possibility of a release of
agent to the atmosphere. Accidental detonations, how-
ever, would not be contained by the overpack contain-
ers and would result in the release of explosive force
and agent to the atmosphere.
Receiving/storage area. Overpacked munitions are
held in this area and, if necessary, warmed prior to
further processing. This area is inside PBNSF and the
effects of an accidental detonation would be greatly
mitigated by facility containment and the munition
overpack.
Unpack area. Once munitions are removed from their
overpacks in the unpack area, the potential for agent
release during an accidental detonation is dependent
on the containment design of PBNSF.
Fill extraction preparation area and fill extraction
and detonation area, including ECC-1, ECC-2, DET,
PWS, auxiliary processing vessels, and DET staging
area. Munitions are handled and moved through the
various emptying and cleaning processes in this area
and are subject to accidental detonation as a result of
handling errors and mishaps. Significant amounts of
agent could be released if a detonation occurs outside
an ECC.
Process hazard analyses are management tools used to
examine the accidents that could happen in segregated areas
of PBNSF. These analyses describe the accidents that could
happen during the processes that take place in the different
areas of PBNSF. Design changes or engineering controls are
instituted to reduce the probability of their occurrence or to
minimize the impacts if they do occur. Another manage-
ment tool, job hazard analyses, describes accidents that could
occur during individual operations in the distinct process
areas. The process and job hazard analyses were being per-
formed as this report was being prepared and were not avail-
able for review by the committee.
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WORKER PROTECTION AND POTENTIAL FOR OFFSITE RELEASE
Finding 3-1: The segregation of operations in the PBNSF
appears to be appropriate; however, the likelihood of acci-
dental detonation cannot be estimated until the process haz-
ard analyses and job hazard analyses have been completed.
Recommendation 3-1: The Army should complete process
hazard analyses and job hazard analyses to provide critical
information before finalizing the design of the Pine Bluff
Non-Stockpile Facility.
PROTECTION OF THE PUBLIC AND THE
ENVIRONMENT
The PBNSF is not designed to contain an occurrence of
the maximum credible event (MCE).6
The MCE at PBNSF is the accidental detonation of a com-
plete GTR (full warhead and rocket motor), resulting in an
energetic force of approximately 17 lb of trinitrotoluene
equivalent and the dispersion of 7 lb of agent. The PBNSF
building, however, is not designed to contain the effects of the
MCE.7 Rather, it is designed with blowout panels, which will
vent internal pressure in the event of the MCE. This design
seems not to be consistent with the mandate to provide maxi-
mum protections for the environment, the general public, and
the personnel who are involved in the destruction of the lethal
chemical agents and munitions (50 U.S.C. Section
1521(c)~1~(A)~. In the committee's view, the only methods of
providing maximum protection are to redesign the building to
contain the current MCE or to take action to reduce the MCE
so that the current design is adequate to contain it. This and
other issues should be resolved in the systematic design inte-
gration review (see Recommendation 2-3~.
The committee notes that the Army's calculations for the
no-effects distances for the MCE show that it extends far
beyond the boundaries of PEA (U.S. Army, 2002b). How-
ever, no deaths outside the boundaries of PEA are calculated
to be caused by an MCE at PBNSF (U.S. Army, 2002b).
The committee did not peer review the air dispersion
modeling performed for the no-effects distance calculation,
6The MCE is defined as the worst single event that could occur at any
time with the maximum release of a chemical agent from a munition, con-
tainer, or process as a result of unintended, unplanned, or accidental occur-
rence (U.S. Army, 1999).
7Peter Wells, Task Engineer, Shaw Environmental, Inc., "PBNSF
Bounding Challenge to HVAC Filters," briefing to the committee on Au-
gust 1, 2003.
The term "maximum protection" is defined in the Defense Appropria-
tion Act of 1996. Such terms are generally applied on a case-by-case basis.
See Appendix D in (NRC, 1999) for a compilation of Army definitions and
to learn how this term may fit into general regulatory risk management
policy.
9The no-effects distance is the downwind distance beyond which no
adverse human health effects (em., excessive contractions of the pupil of
~ "a- 7 —
the eye, muscle tremors, airway tightening, nausea, vomiting, and diarrhea)
would be expected to occur (U.S. Army, 2002b).
37
although members of the committee did perform some lim-
ited confirmatory calculations that included meteorological
data; these calculations suggested that the Army's calcula-
tions were conservative (i.e., more likely to overestimate
concentrations than to underestimate them).
The committee recognizes that the Army is investigating
possible methods for removing the rocket motors from the
warheads so that only the warheads will enter PBNSF, and it
encourages that effort. Based on the information reviewed
by the committee, one or more methods of removing the
motors appear feasible.
Finding 3-2: The committee finds that the safety of personnel
outside the PBNSF may be compromised because the building
is not designed to contain the release of agent from the MCE.
Separating the warhead from the rocket motor and process-
ing only the warhead in PBNSF will increase the safety of
operations inside PBNSF by eliminating the only situation
where the energetic capacity of the munition exceeds the
containment capacity of the building.
Recommendation 3-2: The German Traktor rocket war-
heads should be separated from the rocket motors and only
the warheads should be allowed to enter the Pine Bluff Non-
Stockpile Facility so as to reduce the maximum credible
event to a level that can be fully contained by the structure.
The Army should continue to investigate thoroughly the fea-
sibility of separating the German Traktor rocket motors from
their warheads to determine how and where these operations
can be accomplished safely.
External Monitoring
The heating, ventilation, and air conditioning system will
be monitored at the TWA level using both MINICAMS and
DAAMS placed at the midpoint of the carbon filters, at the
filter-housing vestibules, and at the effluent stack of the heat-
ing, ventilation, and air conditioning system. It is unclear
whether perimeter monitoring will be performed. The PEA
perimeter monitors (DAAMS) for the stockpile disposal fa-
cility might be employed to fulfill this function.
Once the systems contract for PBNSF is awarded, a site
monitoring plan will be finalized in coordination with the
PEA, the Pine Bluff Chemical Activity responsible for stock-
pile storage, and the Centers for Disease Control. This moni-
toring plan presumably will encompass the ability to distin-
guish the point from which any agent is being emitted.
Sampling and Analysis of Liquicl and Solicl Secondary
Wastes at the Pine Bluff Non-Stockpile Facility
Liquicl and Solicl Waste Streams
As noted in Chapter 2, the agent contained in each muni-
tion is sampled and analyzed, first at the Pine Bluff muni-
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38
lions assessment system and again at PBNSF, to ensure that
the subsequent processing and monitoring operations are
appropriate. In general, processing of the munitions gener-
ates three secondary liquid waste streams:
· neutralents
· spent decontamination solutions
· miscellaneous process fluids (hydraulic fluids, sol-
vents, etc.)
The first two liquid waste streams will be monitored for
chemical agent at various points during processing at
PBNSF. All three will be sampled and analyzed before re-
lease from Army control.
Munitions processing generates several types of second-
ary solid wastes:
· metal scrap from munition bodies
· spent carbon from filters
· miscellaneous solid wastes (wipes, personal protective
equipment, dunnage, overpacks, etc.)
The metal scrap may either be decontaminated to the 3Xi°
level and sent to another Army site or government contractor
for recycling or thermally decontaminated to the 5Xii level
on-site and released to civilian recyclers. The spent carbon
and other solid wastes will be sent to a treatment, storage,
and disposal facility (TSDF) for treatment and disposal after
an analysis of the vapors in the headspace of the waste con-
tainers to ensure that the waste conforms to the 3X release
standard.
Planning for the closure of PBNSF will require analytical
procedures that can certify the suitability of materials such
as soil, concrete, and metal for recycling or disposal. A pre-
vious National Research Council (NRC) report (NRC,
2001 c) noted that agent in soil or concrete "is a potential
problem during cleanup and closure operations when these
materials must be certified as agent free." The Armv' s cro-
gram for stockpile demilitarization is developing experience
on the necessary analytical procedures. Research on the fate
of chemical agents in the environment may also be relevant
(Rosenblatt et al., 1996~.
i°3X refers to a level of decontamination at which solids are suitable for
transport for further processing.
ii5X refers to a level of decontamination at which solids may be re-
leased for general use or sold (e.g., as scrap metal) to the general public in
accordance with applicable federal, state, and local regulations. A common
misconception is that 5X means simply that the solid has been placed in a
temperature zone of 1000°F or higher for 15 minutes. In fact, a 5X condi-
tion indicates that the solid has been completely heated to and then held at
a temperature of at least 1000°F for 15 minutes.
ASSESSMENT OF THE ARMY PLAN FOR THE PINE BLUFF NON-STOCKPILE FACILITY
Liquids Sampling and Analysis
Neat agent. As previously noted, PBNSF operations will
include a reconfirmation of the contents of each munition to
be processed. Vapor samples will be drawn from within the
auxiliary processing vessel containing the munition body af-
ter initially accessing the munition fill. Similarly, when muni-
tions are being processed in the PWS, a hole is drilled in the
projectile body to permit removal of a vapor sample for analy-
sis. The agent vapor will be analyzed by gas chromatography
and mass spectrometry according to Army procedures.
Aqueous solutions. The neutralents generated in the
chemical processing trailer reactors as well as other aqueous
streams (e.g., water and 10 percent sodium hydroxide rinses)
likely to be contaminated with agents will be analyzed for
agent concentration before release. These streams will be
sampled by drawing liquid from the neutralization reactors,
the waste retention tanks, or the spent decontamination solu-
tion tanks. The samples will be tested to ascertain that agent
concentrations are below the Army's established 50 ppm
release standard for blister agents. Procedures similar to
those used to characterize wastes from the EDS or the legacy
Munitions Management Device mobile systems will be used
(U.S. Army, 2001a). HD in neutralent will be detected by
coupled gas chromatography and mass spectrometry. The
detection limit of this method is below 5 ppm, which pro-
vides a substantial margin for certifying that the HD concen-
tration is 50 ppm or less. (This method is described in the
Utah Resource Conservation and Recovery Act (RCRA)
permit application for the MMD [DEQ, 19991.) The gas
chromatography/mass spectrometry method for HD in hy-
drolysate is a routine operation, and the committee antici-
pates that the Army can reliably and in a timely manner make
these measurements. The committee did not receive or re-
view information on whether all of the measurements could
be made; such a review is beyond the scope of the charge to
the committee.
The contents of liquid waste storage tanks will be sampled
to ascertain compliance with RCRA standards for hazardous
wastes prior to shipment off-site. Analysis of residual agent
was covered in some detail in at least three earlier NRC re-
ports. The report Integrated Design of Alternative Technolo-
gies for Bulk-Only Chemical Agent Disposal Facilities
(NRC, 2000a) discusses possible reasons for the presence of
residual agent in hydrolysate even though adequate residence
time is provided. The report Occupational Health and Work-
place Monitoring at Chemical Agent Disposal Facilities
(NRC, 2001 c) shows in depth the mustard hydrolysis path-
ways and discusses the high toxicity of some of the mustard
degradation products. Another report, Evaluation of Alter-
native Technologies for Disposal of Liquid Wastes from the
Explosive Destruction System (NRC, 2001a), discusses the
possible presence of residual agent in suspended solids in
EDS hydrolysates and in the cracks and crevices of metal
OCR for page 34
WORKER PROTECTION AND POTENTIAL FOR OFFSITE RELEASE
parts. It concludes that any nonincineration technology used
to treat the hydrolysate must be robust and able to deal with
these issues. The various categories of liquid waste will be
analyzed for toxicity characteristic metals and organics us-
ing the toxicity characteristic leaching procedure.l2 Signifi-
cant concentrations of some metallic corrosion products can
be expected in the GTRs because the chemical agents have
been in contact with the steel casings for nearly 60 years.
It is likely that similar release standards will be applied to
the neutralents and rinses generated from arsenical agents con-
tained in the GTRs. PD, which has vesicant properties in addi-
tion to being a vomiting agent, will probably be held to a
50 ppm release standard like HD and MN-3. Procedures to
analyze for arsenicals are still being developed. The aqueous
streams generated from the arsenical agents will contain toxic
arsenic salts. Arsenic and other toxicity characteristic metals
(as well as toxicity characteristic organics) will be analyzed
under RCRA protocols before the solutions are released to a
TSDF for treatment and disposal. No specific release standard
for total arsenic concentration has been set.l3
Solicis Sampling and Analysis
Decontamination of metal scrap to the 3X level will be
established by analysis of the headspace vapor in the metal
decontamination units (MDUs) in accordance with require-
ments outlined in Army regulations and Department of the
Army document 385-61 (U.S. Army, 2002a). In this proce-
dure, the MDU is sealed and the headspace vapor is ana-
lyzed using MINICAMS systems adapted to the particular
agent being handled in each munitions campaign. Typically,
the MDU is held at 70°F for 4 hours before headspace sam-
pling. The 3X decontamination level requires a headspace
vapor concentration below 0.003 mg/m3 for sulfur mustard
agent.
Other categories of solid wastes are sampled and ana-
lyzed by similar procedures. Typically, the wastes are packed
in a drum, and the sealed drum is allowed to stand at 70°F
i2The toxicity characteristic leaching procedure is discussed at greater
length in Chapter 5.
Conformation obtained at a meeting of the committee, National Research
Council staff, Army personnel, and Stone & Webster staff, Boston, Mass.,
May 21-22, 2003.
39
for 4 hours before headspace sampling. Again, the require-
ment for a 3X decontamination level in campaigns dealing
with HD is a vapor concentration of less than 0.003 mg/m3.
A question has been raised about the suitability of this pro-
cedure for release of packages containing spent carbon or
other filter material. A previous NRC report (NRC, 2001 c)
noted that activated carbon "has a high adsorptive capacity
and could therefore give a very low agent vapor pressure
from headspace sampling even if a substantial loading of
agent remained in the carbon. If the temperature of the car-
bon were raised, this agent could be released, posing a dan-
ger to anyone not properly prepared or equipped."
Nonvolatile Agents in Sorbent Materials
A potentially troublesome problem is the handling of solid
materials containing chemical agents having little vapor
pressure. One example might be the handling of wipes and
dunnage from the processing of GTRs containing diphenyl-
chloroarsine (DA). The soiled materials may contain signifi-
cant quantities of DA, which would not be detectable by the
standard vapor test used to certify 3X level decontamina-
tion. Given proper handling and packaging, these materials
might not be a major hazard to current workers but could be
of concern during subsequent treatment and disposal, par-
ticularly in the event that the Army sends these materials to
off-site TSDFs, as planned. Looking ahead to closure of
PBNSF, similar concerns may apply to concrete or soil on
which DA has been spilled. Recent work in Japan has shown
that DA sorbed on celluloid or pumiced has persisted for
more than 60 years if not exposed to hydrolytic conditions
(Science Council of Japan, 2002~. Even after hydrolysis, ar-
senic-containing residues remained. Research done by the
Japanese Chemicals Evaluation and Research Institute in-
cludes development of methods for analysis of DA and other
arsenicals in the presence of solids (Science Council of
Japan, 2002~.
i4Among the Japanese munitions abandoned in Manchuria after World
War II were cylinders of Agent Red containing mixtures of DA and DC
sorbed on celluloid and pumice as well as projectiles containing neat Agent
Red (a DA/DC mixture).