SUPPLEMENTARY INFORMATION:

DOE has conducted a multi-year program to remove the vast majority of the radioactive waste and key radionuclides contained in 16 underground, single-shell tanks (tanks which do not have secondary containment) and ancillary structures (a catch tank, a process vault with smaller tanks, diversion boxes and buried pipelines), located in WMA C at the Hanford Site. For example, approximately 96 percent of the waste volume and radionuclide activity has been removed from the largest (100 series) tanks using a series of advanced technologies. The tanks and ancillary structures previously stored or transferred a variety of wastes, including liquid waste generated by DOE and its predecessor agencies from the reprocessing of spent nuclear fuel to produce plutonium and other nuclear material for nuclear weapons during the Manhattan Project and Cold War eras.

DOE Manual 435.1-1, which accompanies DOE Order 435.1, Radioactive Waste Management, provides for a rigorous evaluation process that DOE uses to determine whether or not certain waste from the reprocessing of spent nuclear fuel is incidental to reprocessing, is not HLW and may be managed as LLW. This process, in relevant part, requires demonstrating that:

(1) The wastes have been processed, or will be processed, to remove key radionuclides to the maximum extent that is technically and economically practical;

(2) The waste will be managed to meet safety requirements comparable to the performance objectives set out in 10 Code of Federal Regulations (CFR) Part 61, Subpart C, Performance Objectives; and

(3) The waste will be managed, pursuant to DOE authority under the Atomic Energy Act of 1954, as amended, and in accordance with the provisions of Chapter IV of DOE Manual 435.1-1, provided the waste will be incorporated ( printed page 25658) in a solid physical form at a concentration that does not exceed the applicable concentration limits for Class C LLW as set out in 10 CFR 61.55, Waste Classification.

The Draft WIR Evaluation documents and demonstrates that the tanks, ancillary structures, and their residual waste at closure of the WMA C will meet the above-referenced criteria in DOE Manual 435.1-1. DOE is predicating this Draft WIR Evaluation on extensive analysis and scientific rationale, using a risk-informed approach, including analyses presented in the “ Performance Assessment of Waste Management Area C, Hanford Site, Washington” (WMA C PA). Specifically, this Draft WIR Evaluation shows that key radionuclides (those radionuclides which contribute most significantly to radiological dose to workers, the public, and the environment as well as radionuclides listed in 10 CFR 61.55) have been or will have been removed to the maximum extent technically and economically practical. Based on the analyses in the WMA C PA, this draft evaluation also projects that potential doses to a hypothetical member of the public and hypothetical inadvertent intruder for 1,000 years (and beyond) after WMA C closure will be well below the doses specified in the performance objectives and performance measures for LLW. In addition, the analyses demonstrate that there is reasonable expectation that safety requirements comparable to the NRC performance objectives at 10 CFR part 61, subpart C will have been met. As also shown in the Draft WIR Evaluation, the residuals, tanks, and ancillary structures at WMA C closure will have been incorporated into a solid form that does not exceed concentration limits for Class C LLW.

Although not required by DOE Manual 435.1-1, DOE is consulting with NRC on this Draft WIR Evaluation and also making the Draft WIR Evaluation available for comment from the States, Tribal Nations, and the public. After consultation with NRC, carefully considering comments received, and performing any necessary revisions of analyses and technical documents, DOE plans to issue a final WIR Evaluation and a potential determination as to whether the WMA C tanks, ancillary structures, and their residual waste at the time of WMA C closure is non-HLW, and may be managed and disposed of in place as LLW.

83 FR 25657