Challenges Faced by the U.S. Nuclear Regulatory Commission for Activities related to U.S. Department of Energy Waste Determinations

Under the National Defense Authorization Act for Fiscal Year 2005 (NDAA), the Department of Energy (DOE) can determine that certain material resulting from the reprocessing of spent nuclear fuel is not high-level waste (HLW), and therefore does not need to be disposed of in a geologic repository in order to manage the risks that the waste poses. Reprocessing wastes can take a variety of forms including, but not limited to, liquid and sludge waste stored in underground tanks, waste removed from tanks and disposed of elsewhere after processing, and equipment that was utilized in waste processing which has been prepared for disposal. Section 3116 of the NDAA requires DOE to consult with the Nuclear Regulatory Commission (NRC) regarding DOE's non-HLW determinations performed pursuant to the NDAA. The NDAA also requires the NRC to monitor DOE's disposal actions to assess compliance with 10 CFR 61, Subpart C. The NDAA applies only to the States of Idaho and South Carolina. Although the NDAA applies only to the States of Idaho and South Carolina, similar waste determinations may be performed at DOE's Hanford site and West Valley Demonstration Project. The NRC expects to perform similar technical reviews for waste determinations performed at those sites. The Commission directed the staff to take the time necessary to complete its reviews to ensure protection of public health and safety, to make decisions that are transparent, traceable, complete, and as open to the public as practical, and to inform the Commission on how the staff intends to implement its monitoring responsibilities. NRC's waste determination reviews under the NDAA are watched closely by many stakeholders, including environmental groups, other Federal and State agencies, and the public. The complexity associated with the key aspects of making a non-HLW determination imposes significant challenges on the NRC staff. This paper provides an overview of the technical challenges faced by the NRC after passage of the NDAA and describes how those challenges are being addressed. The main challenge addressed in this paper is the differences between disposal of non-HLW and traditional low-level waste. Secondarily, this paper briefly addresses how to ensure consistency of technical reviews, and how to develop risk insights for a complicated system including estimating the impact of real-world features and complexity with simplified computer models. (authors)