negative pressure relative to the surroundings. Operating temperatures for materials contaminated with mustard will be in the range of 275°F to 350°F. Total estimated cycle time from start up to cooldown is 19 to 22 hours, depending on the material and the degree of contamination.

The autoclave is an industrial vacuum cycle unit, 26 in. wide by 78 in. deep by 62 in. high in internal volume. The door opening is 26 by 62 in. The floor loading capacity is approximately 300 pounds. The autoclave is designed to operate at up to 267°F at pressures of 2 to 32 pounds per square inch gage (psig). Materials contaminated with mustard will be heated with steam to a maximum temperature of 267°F and then cooled by the application of a vacuum. Total cycle time is estimated between 7.5 to 8.5 hours.

Thus, PCAPP is not planning to heat secondary and closure wastes to 1000°F for 15 minutes, the traditional method for certifying waste as agent-free and suitable for off-site disposal. Instead, PCAPP will take advantage of the approach based on waste control limits (WCLs) that went into effect in June 2004. There are several variations of the WCL approach. The State of Colorado has approved a vapor screening level (VSL) for certifying waste treated in the SDU or autoclave as agent-free. A gas/vapor sample will be taken at the end of each thermal cycle to determine if the cycle was sufficient to achieve the desired decontamination of less than 1 VSL. Monitoring will require at least two consecutive readings below 1 VSL that are not rising. The monitoring MINICAMS® must pass a post-test agent challenge to ensure that the presence of interferents did not suppress the agent readings. The VSL has been set as 1 short-term exposure limit (0.00001 mg/m3), established by the Army in coordination with the Centers for Disease Control and Prevention (NRC, 2007).

The SDU and autoclave planned for PCAPP should be of sufficient size to handle the secondary and closure waste expected to be generated at BGCAPP. The SDU would have to be operated at higher temperature and possibly for longer times in treating waste contaminated with VX. Available data indicate that the half-life for VX is 4 minutes at 482°F and 0.6 minute at 563°F. Assuming that the rate of destruction is first order with respect to time, the estimated times to achieve six nines (99.9999 percent) destruction and removal efficiency are 80 minutes and 11 minutes, respectively. An appropriate WCL and associated sampling and analysis method would need to be approved by the State of Kentucky. Maximum temperatures in the autoclave may be insufficient to handle VX contaminated wastes.

Finding. The BGCAPP permit would require modification if the MTU/SDU/autoclave were to be used instead of the MPT because the process design would be totally different.

Finding. If used at BGCAPP, the MTU, like the full-size MPT, would first require acceptance testing at the manufacturer’s facility. Both units would then undergo first-of-a-kind testing during systemization.

Finding. Although the footprints of both the MPT and the MTU are similar in area, the MTU will have a longer and narrower footprint that will require modification of the floor plan at BGCAPP.

Finding. The use of supplemental decontamination units and autoclaves at BGCAPP will be required to treat secondary and closure waste if the MTU is selected for processing munitions bodies at BGCAPP. The supplemental decontamination unit and autoclave operating temperatures will not be the same as at PCAPP because higher temperatures are required for GB and VX than for H or HD to achieve thermal decomposition rates suitable for anticipated waste production rates.

Finding. The use of waste control limit guidelines will be required for the disposal of waste exposed to H, HD, GB, and VX if supplemental decontamination units and an autoclave are used at BGCAPP. These guidelines for waste exposed to these agents have already been implemented at other chemical demilitarization facilities.

Finding. A method has not been developed for treating squibs and fuzes from the energetics batch hydrolyzer waste streams in either the MTU/supplemental decontamination unit or the MPT.

Finding. The off-gas treatment systems for BGCAPP and PCAPP are quite similar for the MPT and the MTU. The MTU does not require a particulate cyclone downstream of the bulk oxidizer unit.

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