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EXECUTIVE SUMMARY 11 demilitarization processes has not been developed, with research this approach might well be successful. All the above low-temperature, low-pressure, liquid-phase processes might be used to treat liquid waste streams but not be directly applicable to contaminated metal parts or energetics. Moderate-Temperature, High-Pressure Oxidation In wet air oxidation, organic materials in a dilute aqueous mixture axe oxidized at elevated temperatures and pressures. Supercritical water oxidation operates at still higher temperatures and pressures (above the critical point of water at which hydrocarbons, for example, are highly soluble). Both wet air and supercritical water oxidation processes can detoxify and convert residual organics to carbon dioxide. Wet air oxidation requires residence times of greater than 1 hour. Even then, more refractory organic compounds remain; however, these compounds are judged to be suitable for subsequent biological degradation. Supercritical water oxidation can achieve a greater conversion of all organics in less than 10 minutes. Because pure oxygen is used in this process, waste gas is primarily carbon dioxide, which can, if necessary, be removed as solid calcium carbonate (limestone). Adaptation of wet air oxidation to use pure oxygen would require a pilot plant program. Both processes can treat all three principal agents in the U.S. stockpile (GB, VX, and the mustard compounds). Both are expected to be capable of treating a slurry of finely divided energetics if care is exercised in the control of feed rates. Some mechanical addition to the disassembly process would be required to remove and make a slurry of the energetics. Their removal from containers is not expected to be complete, so some energetics residues would still need to be destroyed in a metal deactivation process involving high-temperature treatment, as in the baseline system. Supercritical water oxidation could also be used as an afterburner to oxidize gas products of pyrolysis or other processes. This approach is an alternative to the combustion variations discussed later. It has the disadvantage of requiring gas compression to 3,000 psi or higher. However, it also offers high conversion efficiency. Application of these processes to chemical agents would still require a problem-solving stage and would require pilot plant studies. The high operating pressure would require appropriate confinement, as in industrial practice. Currently, baseline facilities are remotely operated and designed for energetics explosions and capture of agent release. The high-pressure oxidation process would call for some extension of these safeguards.