Disposal of Activated Carbon from Chemical Agent Disposal Facilities (2009)

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2 Uses and Management of Activated Carbon at Chemical Agent Disposal Facilities USED CARBON SOURCES • In bulk form in horizontal filter beds in the PFS units; and Activated carbon is used at every site where chemi- • In canister filters attached to M-40 protective cal weapons are being destroyed in the United States. masks. Its usefulness derives from its adsorptive properties that readily remove agent or other toxic chemicals from the Figure 2-1 is a picture of the nine filter units (“filter air. Activated carbon is used at chemical agent disposal farm”) for the air leaving a munitions demilitarization facilities to filter all air leaving agent-contaminated building (MDB) heating, ventilation, and air condition- areas where remote processing of agent and munitions ing (HVAC) system. At least one of the filter units in the takes place and all vent gas streams from processing filter farm is a spare, which allows a filter tray change- vessels. Activated carbon is used for other reasons as out during operations by shutting down and isolating well: the unit where changeout is taking place. Figure 2-2 is a schematic of the airflow through the six filter banks • To filter ventilation air supplied to occupied work that typically comprise each operational MDB HVAC areas that are normally free of agent; filter unit. The automatic continuous air monitoring • To capture any agent vapors from leaking weap- system (ACAMS) and the depot area air monitoring ons in chemical weapon storage bunkers; and system (DAAMS) (not shown in Figure 2-2), which are • To protect all personnel working within the chem- located between Banks 1 and 2, 2 and 3, 3 and 4, and ical limited area at each facility; it is contained in 4 and 5, monitor for the presence of agent. A filter tray a canister that is inserted into a face mask. is depicted in Figure 2-3, and the flow of air through the filter tray is shown in Figure 2-4. This filter tray is The activated carbon, which is granular, is used in used in all filtering units except the PFS filters and the three configurations: M-40 mask canisters. Figure 2-5 shows a PFS. Figure 2-6 is a schematic • Filter trays that are used in all air filter units except of the PAS/PFS flow configuration including the PFS the pollution abatement system (PAS) filtration units, and Figure 2-7 is a schematic of the combus- system (PFS) and the M-40 gas mask canisters; tion gas flow through the PFS. The PFS beds, shown in a vertical orientation in the schematic, are actually The “chemical limited area” is the fenced-in area at a facil- horizontal in the PFS; however, the flow path sequence ity subject to surety monitoring due to the presence of chemical is as shown in Figure 2-7. Figure 2-8 shows an M-40 agent(s). protective mask with the filter canister attached. 15 

16 DISPOSAL OF ACTIVATED CARBON FROM CHEMICAL AGENT DISPOSAL FACILITIES conclusion does not preclude plant management from changing out filters from Banks 1 and 2 for other rea- sons, e.g., to measure conditions of the carbon. As indicated in Table 2-1, changeout of the carbon in Banks 1 and 2 would take place if agent break- through above the short-term limit is detected between Banks 2 and 3 at the Tooele, Anniston, and Pine Bluff Chemical Agent Disposal Facilities (TOCDF, ANCDF, and PBCDF). At Umatilla Chemical Agent Disposal Facility (UMCDF), the policy is that changeout would occur if agent breakthrough above the short-term limit is detected between Banks 3 and 4. However, as has been and continues to be the case at the other sites, the committee does not expect that it would ever become necessary for MDB HVAC Bank 3 carbon at UMCDF to be changed out due to contamination. For this reason, for each site covered in this report the first two banks of MDB HVAC carbon will be considered to be exposed to agent and the last four banks will be considered to be unexposed carbon. The PFS filters are not expected to be exposed to agent during normal operation of the liquid incinerator (LIC), the metal parts furnace (MPF), or the deactiva- tion furnace system (DFS) and their respective PAS units. The PFS units at the more recently constructed FIGURE 2-1  The nine activated carbon filter units for the ANCDF, PBCDF, and UMCDF were not required MDB HVAC system. SOURCE: Robie Jackson, Waste by the regulations applicable to these facilities that Management Manager, ANDCF, and Tracy Smith, Trial Burn implement the Resource Conservation and Recovery Manager, ANCDF, “The use of carbon at ANCDF,” Presenta- Act (RCRA), but they were included in the design of tion to the committee, June 5, 2008. these facilities as an extra precaution to relieve public concerns about the possibility of uncontrolled gaseous emissions. The report Carbon Filtration for Reducing A list of typical uses for carbon filter units in a Emissions from Chemical Agent Incineration examined chemical agent disposal facility using incineration various technical and risk-related aspects surrounding for agent destruction is given in Table 2-1. The used the use of PFSs at chemical agent disposal facilities carbon from most processes is not expected to be con- (NRC, 1999). From the start of operations in 1996, taminated with agent. The only two places where used TOCDF has operated without a PFS but was adding carbon is expected to become exposed to agent during units downstream of the two LICs and the MPF as this normal operations are the unit filters for the agent col- report was being prepared. Sulfur-impregnated carbon lection system (ACS) and Banks 1 and 2 of the MDB is being installed in these units to capture mercury from HVAC filters. The semicontinuous monitoring (noted in the incineration of mercury-containing mustard agent. Table 2-1) by a combination of near-real-time ACAMS The PFS at ANCDF, PBCDF, and UMCDF will also and DAAMS after Banks 1, 2, 3, and 4 establishes that use sulfur-impregnated carbon when these facilities there is no exposure to agent beyond Bank 2. This are processing mustard agent-containing munitions and ton containers. Table 2-2 estimates total quantities of used carbon The DAAMS monitors consist of adsorption tubes that confirm expected to be generated during disposal operations the ACAMS monitors since they sample any agent in the airstream on a continuous basis but are analyzed only periodically (several and site closure for each of the incineration-based times daily). Measurements to date beyond Bank 2 have been non- chemical agent disposal facilities currently operating detect for agent. and for the neutralization (hydrolysis)-based Newport 

USES AND MANAGEMENT OF ACTIVATED CARBON AT CHEMICAL AGENT DISPOSAL FACILITIES 17 FIGURE 2-2  Schematic representation of airflow through the six filter banks that make up each MDB HVAC filter unit. Carbon filters each contain 48 filter trays arrayed in six columns and eight rows, with each tray oriented in horizontal position. The 85 FIGURE 2-2.eps indicates 85 percent efficiency for the particulate prefilter; H indicates HEPA filter; F indicates filter; and C indicates carbon bitmap filter. SOURCE: Robie Jackson, Waste Management Manager, ANCDF, and Tracy Smith, Trial Burn Manager, ANCDF, “The use of carbon at ANCDF,” Presentation to the committee, June 5, 2008. Chemical Agent Disposal Facility (NECDF), which vides complementary estimates of the quantities of car- recently completed destruction of the stockpile of bulk bon that can be considered unexposed to agent and the VX nerve agent stored in ton containers at the site. operations where this carbon was used. These estimates Table 2-2 also indicates the quantities of carbon that include used carbon from both operations and closure the Army currently anticipates for off-site and on-site and are based on data provided by the Army showing treatment. which carbon it expects will be treated on-site in the Table 2-3 estimates the quantities of carbon antici- MPF (exposed) and which can be slated for off-site pated to be exposed to agent and the operations that shipment (unexposed.) produce them at each of the Chemical Materials It is important to note that the numbers in Tables Agency (CMA) incineration facilities. Table 2-4 pro- 2-3 and 2-4 represent calculated estimates as of Sep- tember 2008 and are subject to changes based on operational factors, design modifications, and ongoing developments and negotiations concerning permitting and regulatory requirements for on-site analysis and treatment and off-site shipment and disposal. There is also some variation in how the data from which these tables were generated was compiled at each site (e.g., dry weight or actual weight, frame and hardware weight included or not). However, the main point made by Tables 2-3 and 2-4 is that the anticipated total amount of exposed carbon (~508,400 lb) is about one-fourth the anticipated total amount of unexposed carbon (~2,107,800 lb), or only about one-fifth the total used carbon (~2,616,200 lb) expected from operations and closure at the four incineration sites. FIGURE 2-3  A filter tray. SOURCE: Robie Jackson, Waste Also evident from Table 2-3: The overwhelming Management Manager, ANCDF, and Tracy Smith, Trial Burn majority of exposed carbon comes from the MDB Manager, ANDCF, “The use of carbon at ANCDF,” Presenta- HVAC system, which is also the source of about half tion to the committee, June 5, 2008. the unexposed carbon, as shown in Table 2-4. The PFS 

18 DISPOSAL OF ACTIVATED CARBON FROM CHEMICAL AGENT DISPOSAL FACILITIES FIGURE 2-4  Airflow path through a filter tray. SOURCE: Susan Ankrom, SAIC Task Manager, ANCDF, “Published values for agent loading capacity of MDB and PFS carbon,” Presentation to the committee, June 6, 2008. FIGURE 2-4.eps bitmap carbon, including the sulfur-impregnated carbon that the bulk of the remaining carbon that can be consid- will be used to capture mercury emissions from the ered unexposed to agent, as discussed later. It is also processing of mustard agent munitions, constitutes worthwhile noting that RCRA regulations at 40 CFR 261.10(a)(2)(ii) allow generators of solid waste to use the “knowledge of their waste” to determine whether the RCRA regulations apply to it. The data provided from the neutralization-based NECDF indicate that the used carbon generated during the now-completed disposal operations and ongoing facility closure comes primarily from MDB HVAC and process filters (270,000 lb) but also from other sources (nearly 11,000 lb). At the time this report was being prepared, 200,000 lb of this carbon had been shipped to Calgon Carbon Corporation, a carbon supplier, for reactivation and has never been returned to the NECDF inventory. The Army has released it for sale on the open market. There is no requirement for NECDF to sample and analyze the used exposed carbon, which is managed as a listed hazardous waste under the Indi- FIGURE 2-5  PFS filter unit. SOURCE: Robie Jackson, Waste Management Manager, ANCDF, and Tracy Smith, Tri- What is commonly termed “generator knowledge” as applicable al Burn Manager, ANCDF, “The use of carbon at ANCDF,” to used carbon from chemical agent disposal facilities is discussed Presentation to the committee, June 5, 2008. further in Chapter 3 and later chapters. 

USES AND MANAGEMENT OF ACTIVATED CARBON AT CHEMICAL AGENT DISPOSAL FACILITIES 19 FIGURE 2-6  Schematic of the PAS/PFS flow configuration including the PFS filter unit. The carbon filter units refer to two zones of the PFS unit, which are actually in series and not in parallel as shown. SOURCE: Robie Jackson, Waste Manage- FIGURE 2-6.eps ment Manager, ANCDF, and Tracy Smith, Trial Burn Manager, ANCDF, “The use of carbon at ANCDF,” Presentation to the committee, June 5, 2008. bitmap FIGURE 2-7  Schematic representation of the combustion gas flow path through the PFS. The carbon filters, denoted by “C,” are actually horizontal beds with gas flow from the first bed through the second bed and then out through the HEPA filter, denoted by “H.” “F” is a generic denotation for various types of filters. The efficiency of the particulate prefilter is 85 percent. SOURCE: Robie Jackson, Waste Management Manager, ANCDF, and Tracy Smith, Trial Burn Manager, ANCDF, “The use of carbon at ANCDF,” Presentation to the committee, June 5, 2008. FIGURE 2-7.eps bitmap 

20 DISPOSAL OF ACTIVATED CARBON FROM CHEMICAL AGENT DISPOSAL FACILITIES Only the used activated carbon from the PFS is handled in bulk form; i.e., the used carbon is not con- tained in filter trays. The used carbon from PFS filters is emptied as a loose solid into plastic bags, and the bags are placed in polyethylene drums for storage and disposal. The PFS filter beds are arranged in two hori- zontal zones in series in the process vent gas stream with ACAMS monitoring between the zones. In some facilities, combustion gas flowing to Zone 1 is not monitored for agent because it is expected to be free of agent during normal plant operation based on tests performed when the facility was licensed for operation. While the PFS carbon is not expected to be exposed to agent, each disposal facility has installed a DAAMS FIGURE 2-8  An M-40 protective mask with the filter C-2 monitor downstream of Zone 1. The sampling tubes canister attached. SOURCE: Robie Jackson, Waste Manage- in this monitor are regularly removed and analyzed in ment Manager, ANCDF, and Tracy Smith, Trial Burn Man- the laboratory. ager, ANCDF, “The use of carbon at ANCDF,” Presentation to the committee, June 5, 2008. Finding 2-1.  At some chemical agent disposal facili- ties, no depot area air monitoring system monitor has been installed in front of Zone 1 of the pollution abate- ment system filtration system. ana Department of Environmental Management 1001 waste code and is to be disposed of accordingly, at Recommendation 2-1.  If the activated carbon in a an approved treatment, storage, and disposal facility pollution abatement system filtration system unit at a (TSDF). chemical agent disposal facility is ever to be changed out, consideration should be given to installing a depot area air monitoring system (DAAMS) upstream of MANAGEMENT OF USED CARBON Zone 1 (the first carbon bed) of the pollution abatement Two considerations dictate how used carbon is system filtration system if none exists now. The addi- handled on-site: tion of this DAAMS unit would document the absence of agent in the gas stream flowing to the carbon in Zone • Is the carbon contaminated with agent? 1, even though no agent is expected to be released as a • How much agent is present on the carbon? result of incineration and subsequent scrubbing of the incineration flue gases. The current practice when a filter tray containing exposed carbon is removed from operation is to first While current management philosophy dictates han- bag the tray in two plastic bags and then place the dling the used carbon as contaminated material, most double-bagged tray in a 95-gallon polyethylene drum of the used carbon will be unexposed even at the end of (see Figure 2-9), which is stored for future disposal. agent disposal operations, barring an airborne release This practice avoids unnecessarily exposing personnel on-site. Furthermore, standard operating procedures to agent as would be the case if the carbon were to be may preclude the exposure of filters in air streams that removed from the filter trays prior to packaging for contain agent. Four key factors that reduce the agent storage and disposal. While this approach minimizes loading on the MDB HVAC filter are these: any chance of exposure to agent during packaging, it makes it difficult to characterize the amount of agent 1. Keeping agent vapor levels low in Level A (the that might be present on the used carbon. Recall from most contaminated) process areas by periodic Table 2-1 that each MDB HVAC filter unit typically decontamination with caustic to clean up spills consists of six banks and each bank consists of 48 filter and leaks. trays. Each filter tray is specified to contain 48.3 lb of 2. Providing ACAMS and DAAMS monitoring carbon. between zones. A vestibule is provided to change 

USES AND MANAGEMENT OF ACTIVATED CARBON AT CHEMICAL AGENT DISPOSAL FACILITIES 21 TABLE 2-1  Uses of Activated Carbon Filters at Chemical Agent Disposal Facilities Use Typical Configuration Expected Agent Exposure Level ACS filter 1 filter tray per ACS High. Filters are exposed to vent gases flowing from headspace of the agent collection tanks, which feed agent to the LIC. Banks 1 and 2 of each filter unit of the Each filter unit bank contains 48 horizontal High. Filters in Banks 1 and 2 are exposed to any agent MDB HVAC system filtersa filter trays typically arranged in 6 columns vapors in air from the processing rooms. Filters in Banks 1 and 8 rows. Bank 1 is the first bank that and 2 are changed if agent breakthrough above the short-term MDB air encounters and Bank 2 is the limit is detected between Banks 2 and 3. A filter housing second bank. Semicontinuous monitoring vestibule is installed for removal of Bank 1 and 2 filter trays (ACAMS/DAAMS) is used after Banks 1 in a controlled environment.b and 2. Banks 3, 4, 5, and 6 of each unit of the Each filter unit bank contains 48 horizontal None. ACAMS monitoring between Banks 2 and 3 provides MDB HVAC system filters filter trays typically arranged in 6 columns data that demonstrate the lack of exposure.b and 8 rows. Air from Bank 2 flows through Banks 3 to 6 before flowing to the plant stack. Semicontinuous monitoring (ACAMS/ DAAMS) is used after Banks 3, 4, and 5. PAS/PFS filters 3 filter units; 2 banks of bulk carbon/unit None. By design, agent is destroyed by incineration in the DFS, LIC, and MPF. Agent would only be present in offgas during upset operations. DFS cyclone enclosure filter 1 filter unit; 2 filter banks; 12 trays/bank None. Agent could be present in ash during upset operations. At TOCDF the cyclone ash collection system enclosure has no filter and is vented to the MDB HVAC system filters. Laboratory hood exhaust filter 1 filter unit; 2 banks/unit; 48 filter trays/bank None. Normally not expected based on laboratory procedures. M-40 mask canisters 1 canister/mask None unless a mask used in area where agent vapors are present. Control room ventilation air supply filter 1 filter unit; 2 banks/unit; 48 filter trays/bank None. No agent expected in ambient air. Laboratory ventilation air supply filter 1 unit; 2 banks/unit; 48 filter trays/bank None. No agent expected in ambient air. Personnel and maintenance building 1 filter unit; 1 bank/unit; 36 filter trays/bank None. No agent expected in ambient air. ventilation air filters Site maintenance facility; mechanical 2 filter units each; 5 filter trays/unit None. No agent expected in ambient air. maintenance facility; electrical maintenance facility, protection facility ventilation air supply filters aTypically, there are 9 MDB HVAC filter units each consisting of 6 banks of filters arranged in series with respect to airflow. bAt UMCDF, the policy is to change the filters in Banks 1, 2, and 3 if agent breakthrough above the short-term limit is detected between Banks 3 and 4. However, in this report, the committee has formulated its findings and recommendations and supporting text on the expectation that MDB HVAC Bank 3 filter at UMCDF will not experience agent exposure above the short-term limit. This expectation is based on the monitored experience to date concerning Banks 1 and 2 carbon at all sites. SOURCE: Adapted from Timothy Garrett, Site Project Manager, ANCDF, “Carbon management by site,” Presentation to the committee, July 23, 2008. out the filter trays in Banks 1 and 2 when agent loading. The nerve agent GB, which is more breakthrough is detected at the outlet of Bank 1 volatile, presents the potential for high carbon filters. Figure 2-10 shows a vestibule on the side filter loading. of an MDB HVAC unit. Thus, used activated car- 4. The degradation of agent on activated carbon at bon from Bank 3 and higher is never exposed to varying rates in the presence of moisture in the chemical agent during normal operation. filtered gas stream (see Chapter 4). 3. The low volatility of VX and distilled mustard agent, HD, which results in low carbon filter Current evaluations of the long-term behavior of agents on activated carbon indicate that chemical agents are hydrolyzed by the water adsorbed on the See footnote b in Table 2-1. carbon. (See Table 2-5 for information on properties of 

22 DISPOSAL OF ACTIVATED CARBON FROM CHEMICAL AGENT DISPOSAL FACILITIES TABLE 2-2  Estimated Carbon Waste Inventories (in TABLE 2-3  Summary of Sources and Estimated Pounds) for CMA Chemical Agent Disposal Facilities as of Inventories (in Pounds) of Carbon Exposed to Agent at September 29, 2008a CMA Incineration Sites During Operations and Closurea Changeout Total On-site MDB M-40 Mask Existing Prior to Generated Off-site Treatment Site ACS Laboratory HVAC Canistersb Other Site Inventory Closure at Closure Shipment in MPF ANCDF 3,600 <100 153,800 1,400 ANCDF 18,000 209,700 573,700 642,700 158,700 UMCDF 4,800 <100 47,500 2,100 UMCDF 148,100 60,400 304,000 598,200b 54,400 TOCDF 200 15,300c 159,000 3,100 20,800d TOCDF 367,700 40,000 325,000 537,400 195,300 PBCDF 1,200 <100 95,600 <100 PBCDF 33,100 48,500 302,400 295,100c 96,900 NECDF 235,000 0 35,000 270,000 0 Total 9,800 15,300 455,900 6,600 20,800 aWeights aWeights may include carbon, carbon tray materials, and packaging. may include carbon, carbon tray materials, and packaging. Quantities have been rounded. Information is as of September 29, 2008. Estimates of exposed carbon made bInformation updated as of March 17, 2009. Includes 140,000 lb ad- on basis of anticipated on-site treatment. Quantities have been rounded. ditional PFS carbon since September 29, 2008, estimate. bCarbon from M-40 mask canisters, while normally not exposed to agent, cInformation updated as of March 18, 2009. is generally expected to be treated as exposed at most sites in view of the relatively small amounts involved. SOURCE: Adapted from information provided to the committee by Timothy cThis carbon amount is the result of the significantly larger amounts Garrett, Site Project Manager, ANCDF, as of September 29, 2008. and greater variety of materials tested over the longer duration of TOCDF operations compared to other sites. dThis carbon amount is the result of a ton container sampling operation unique to the site. agents.) Chapter 4 provides a detailed discussion of the SOURCE: Adapted from information provided to the committee by Timothy chemical reactions of agent on activated carbon. Garrett, Site Project Manager, ANCDF, September 29, 2008. At chemical agent disposal facilities using incinera- tion to destroy agent, the ACS filters and personnel protective equipment canister carbon are expected The ACS filter trays and gas mask canisters, includ- to be disposed of on-site in the MPF. CMA plans ing the metal canister frames and canister bodies, to dispose of all other used carbon by bagging and are double bagged, placed in 95-gallon polyethylene drumming it and eventually shipping it to a qualified drums, and sent to storage. Subsequently, when operat- TSDF. As noted previously, the bulk carbon from the ing schedules permit, they are removed from the drums, PFS will be bagged and drummed as loose material. placed in waste incineration containers, and treated in All other used carbon will be contained in metal filter the MPF. In the MPF, the spent carbon and container trays similar to those used in the MDB HVAC (see are treated to an agent-free condition for several hours Figures 2-3 and 2-4). as they pass through each zone. The MPF process meets TABLE 2-4  Summary of Sources and Estimated Inventories (in Pounds) of Unexposed Carbon Used at CMA Incineration Sites During Operations and Closurea PFS Sulfur- PFS Carbon MDB Impregnated Control Site (Regular) Laboratory HVAC Carbon Room Other ANCDF 115,500 15,400 414,700 69,300 15,400 12,400 UMCDF 270,000b 10,600 95,000 200,000b 5,300 17,300 TOCDF 0c 6,300 318,000 240,000d 5,000d 2,500d PBCDF 80,800e 15,900 127,500 48,500f 8,000 14,400 Total 466,300 48,200 955,200 557,800 33,700 46,600 aWeights may include carbon, carbon tray materials, and packaging. Information is as of September 29, 2008, unless otherwise noted. Estimates of unexposed carbon made on basis of anticipated off-site treatment. Quantities have been rounded. bInformation updated as of March 17, 2009. cPFS was only recently added at TOCDF for the processing of mercury-contaminated mustard agent and therefore only sulfur- impregnated carbon is to be used. dInformation updated as of March 19, 2009. eInformation updated as of March 18, 2009. Of this amount, 48,500 lb has already been shipped off-site. fInformation updated as of March 18, 2008. SOURCE: Adapted from information provided to the committee by Timothy Garrett, Site Project Manager, ANCDF, September 29, 2008. 

USES AND MANAGEMENT OF ACTIVATED CARBON AT CHEMICAL AGENT DISPOSAL FACILITIES 23 FIGURE 2-10 Vestibule on the side of an MDB HVAC unit. SOURCE: Photograph taken at ANCDF and provided courtesy of ANCDF. For the used carbon that is to be shipped to a quali- FIGURE 2-9  A 95-gallon drum for storage of used carbon fied TSDF, a permitted protocol is needed. At the time filter trays. SOURCE: Robie Jackson, Waste Management this report was being written, CMA was working on Manager, ANCDF, and Tracy Smith, Trial Burn Manager, such a protocol that uses sampling, extractive analysis, ANCDF, “The use of carbon at ANCDF,” Presentation to the and transportation risk assessment (TRA) guidelines to committee, June 5, 2008. establish the conditions under which the carbon can be safely transported to an off-site qualified TSDF with- out prior on-site treatment (see Chapter 4 for further discussion on an analysis protocol). The waste control the temperature and time criteria, 1000°F for at least 15 limits for off-site shipment at operating sites other than minutes, to allow the treated residual materials leaving UMCDF are 20 parts per billion (ppb) for GB and VX the MPF to be safely released to a commercial disposal and 200 ppb for mustard agent; for UMCDF, the state facility. However, any carbon must be kept in the MPF has set permit compliance concentrations that serve until it has finished smoldering. Treating all the carbon a similar purpose: at 13 ppb for VX, 16 ppb for GB, filter units in the MPF would seriously delay the sched- and 152 ppb for HD (see Chapter 3). The CMA TRA ule for completion of facility operations and closure. approach requires the chemical agent disposal facility TABLE 2-5  Pertinent Physical Properties of the Chemical Agents and Mercury Nerve Agent Blister Agent Elemental Property GB VX HD Mercury Vapor pressure (torr) 2.48 at 25°C 8.78 × 10–4 at 25°C 0.106 at 25°C 1.2 × 10–6 at 20°C 0.410 at 0°C 4.22 × 10–5 at 0°C Volatility (mg/m3) 18,700 at 25°C 12.6 at 25°C 75 at 0°C 0.884 3,370 at 0°C 0.662 at 0°C 906 at 25°C Boiling point (°C) 150 292 218 357 Freezing point (°C) −56 <−51 14.45 −38.87 Solubility (g/100 g water) Miscible 5% at 21.5°C 0.092 at 22°C Insoluble SOURCE: Lide (1985) and U.S. Army (2005). 

24 DISPOSAL OF ACTIVATED CARBON FROM CHEMICAL AGENT DISPOSAL FACILITIES to estimate the maximum amount of agent that might is known as “generator knowledge” (as described in be present in each carbon container. This amount will Chapter 3). It should be the basis for determining which then be compared to the maximum amount determined used carbon can be considered unexposed to agent and for safe shipment by a “bounding” TRA prepared thereby minimizing the use of sampling and analysis for the anticipated size and method of shipment (see for final disposition of the carbon. Chapter 7). REFERENCES Finding 2-2.  Carbon is used at many locations in a chemical agent disposal facility. However, it will be Lide, D.R. 1985. Handbook of Chemistry and Physics, 66th edition. Boca Raton, Fla.: CRC Press. exposed to agent-contaminated air or process vent NRC (National Research Council). 1999. Carbon Filtration for Reducing streams in only two locations during normal operation: Emissions from Chemical Agent Incineration. Washington, D.C.: Na- the agent collection system vent filters and Banks 1 tional Academy Press. U.S. Army. 2005. Potential Military Chemical/Biological Agents and and 2 of the heating, ventilation, and air conditioning Compounds. FM3-11.9/MCRP3-37.1 B/NTRP3-11.32/AFTTP (I) filter units. 3-2.55, January. Fort Monroe, Va.: U.S. Army Training and Doctrine Command. Recommendation 2-2.  A recognized means for char- acterizing hazardous waste for regulatory purposes