High-hazard waste, disposal technology

Based on these principles, the hazardous waste classification system recommended by NCRP includes three classes of waste exempt, low-hazard, and high-hazard waste. Each waste class is defined in relation to the type of disposal system (technology) that is expected to be generally acceptable in protecting public health as follows ... 

High-Hazard Waste - Requires disposal technology more isolating than dedicated near-surface facility for hazardous wastes (e.g., geologic repository)... 

Technical requirements on treatment and disposal of spent fuel, high-level waste, and transuranic waste established under AEA should be largely unaffected by the presence of waste classified as hazardous under RCRA Some of these wastes meet technology-based treatment standards for hazardous chemical waste established by EPA (e.gvitrified high-level waste is an acceptable waste form under RCRA). Alternatively, a finding that disposal of the radioactive component of the waste complies with applicable environmental standards established by EPA under AEA can serve to exempt the disposal facility from prohibitions on disposal of restricted hazardous chemical wastes under RCRA [e.g., disposal of mixed transuranic waste at the Waste Isolation Pilot Plant (WIPP)]. 

A number of dispositions could be acceptable for high-hazard chemical waste, including destruction (e.g., incineration), treatment to reduce the hazard to levels that would be acceptable for near-surface disposal, or disposal using a technology considerably more isolating than a near-surface facility. At the present time, there are no planned alternatives to near-surface facilities for disposal of high-hazard chemical wastes in the United States.16 However, there do not appear... 

At the present time, there is essentially only one class of hazardous chemical waste (i.e., a waste either is hazardous or it is not), without regard for the amounts of hazardous substances in the waste. Establishment of a risk-based waste classification system would allow for the possibility of two classes of hazardous chemical waste based on the amounts of hazardous substances, consistent with the present situation for radioactive waste, with the attendant implication that high-hazard chemical waste that contains the highest amounts of hazardous substances would require a disposal technology substantially more isolating than a near-surface system. 

MGC-PLASMA Ltd. in Muttenz, Switzerland has developed (under licence from Californian Retech Inc.) a process technology that uses plasma burners to treat hazardous waste and contaminated soil in the available high-temperature zone. A special feature is that the residue is completely harmless and does not need to be disposed of at a hazardous waste dumping site. In this case arsenic will be firmly bound in a glass matrix as slag. 

According to the vendor, only particles from about 2 mm to 50 p,m in size can be processed by magnetic barrier separation. Some bench-scale studies suggest that high feed rates decrease separation efficiency. Materials undergoing magnetic barrier separation must then be processed by some treatment technology before the hazardous component of the waste can be disposed. 

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