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REQUIREMENTS AND CONSIDERATIONS FOR CHEMICAL DEMILITARIZATION TECHNOLOGIES 84 further judgment must be made about the ability of any alternative technology to decontaminate metal parts, explosives, propellants, dunnage, and other components. (It may be possible to deal with dunnage by disposal in hazardous landfills.) Decontamination Standards The Army has developed data over a number of years in support of the current 3X and 5X criteria (see Appendix H). Thins work has included a variety of tests on the liquid forms of all agent types, at various temperatures and times, and with and without oxygen present. Tests have also addressed the decontamination of solids containing the different agents. Previous Army experience showed that past chemical treatment processes left residual agent contamination on metal parts that was detectable on subsequent thermal treatment.2 However, these activities have not included the use of somewhat more reactive chemicals, such as ammonia gas or corrosive adds, at elevated temperatures and for longer times. In principle, with further research and proper choice of reagents, it may be possible to chemically decontaminate metal parts. New ways to certify such decontamination would have to be developed. In conjunction with a development program to chemically destroy agent from ton containers, research to identify low-temperature chemical processes that would match the 5X thermal treatment decontamination would be useful. These results suggest that some consideration should be given to the fundamentals of the problem to indicate the likelihood that similar alternative technology could achieve the equivalent of full 5X decontamination. Current analytical techniques can measure 0.6 ng/m3. For GB, with a molecular weight of 140, this is equivalent to 2.6 Ã 1012 molecules/m3. The typical solids waste debris box being sampled holds about I to 2 m3 of solid wastes. Because GB has a molecular diameter of roughly 10 angstroms, the detectable number of molecules in such a debris box, if spread out into a monomolecular layer, would have a surface area of only a few square millimeters. GB readily wets metal surfaces, and thus only a few small cracks or crevices would be required to contain more than the allowable residue of GB. Further, removal of agent from crevices is likely to be much slower than from an exposed flat surface, because of the limited surface area at the opening of a crevice, the possible blocking of the opening by reaction by-products, and the reduced vapor pressure of the liquid in a crevice. The incomplete reaction observed with decontamination solution is probably due 2 U.S. Army Program Manager for Demilitarization, presentations to the committee at its March 9-10, 1992, meeting.
