DOE OSTI2015
Greater-Than-Class C (GTCC) waste is a low level radioactive waste (LLRW) that exceeds the Class C concentration limits in Part 61.55 of Title 10 of the Code of Federal Regulations. Typically, this waste consists of irradiated metal components from reactors such as core shrouds, support plates, and core barrels, as well as filters and resins from reactor operations and decommissioning. Sealed sources used at hospitals, medical schools, research facilities, and universities can also be classified as GTCC waste. A third category, 'Other Waste', consisting of contaminated equipment, rubble, scrap metal, filters, soil, and solidified sludges may be classified as GTCC waste based on their differing radionuclides and concentration levels. The Low-Level Radioactive Waste Policy Amendments Act of 1985 requires the Federal Government to take responsibility for the disposal of GTCC waste. All GTCC waste created from U.S. Nuclear Regulatory Commission (NRC) licensed activities, under the Atomic Energy Act of 1954, as amended, must be disposed of in an NRC licensed facility that has been determined to be adequate to protect public health and safety. Information from Argonne National Laboratory's supplemental report on GTCC waste from 2010 anticipates that the total volume of GTCC waste will be approximately 8,800 m{sup 3} (311,000 ft{sup 3}) and the projected activity of that waste will be 5.92 x 10{sup 6} TBq (160 MCi) with generation activities ending in 2083. Currently, there is no pathway for the disposal of GTCC waste in the United States. A performance-based approach may be used to subdivide GTCC waste into various waste streams by reviewing the characteristics of GTCC waste with its associated hazards. Characteristics of GTCC waste include half-life and concentration. In creating the 10 CFR Part 61 waste classification tables, which define GTCC concentrations, a number of assumptions were made regarding waste inventory and exposure scenarios for the inadvertent intruder for a generic LLRW disposal facility. The findings from other exposure scenarios (e.g., construction, agriculture, well drilling), together with the findings from evaluations of radiological characteristics of GTCC, could be used as part of a performance-based approach for categorizing GTCC waste. The findings may determine that some GTCC waste streams will be closer in characteristics to Class C waste, while other GTCC waste streams will have characteristics similar to high-level waste and may require a higher degree of isolation from the public. The application of a site-specific and performance-based approach to GTCC waste stream characterization could assist the NRC in developing specific technical requirements for future disposal of various types of GTCC waste. Examples of part of a performance-based approach that examine and evaluate the radiological characteristics of GTCC waste will be presented. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗