Testing the PCSA Tool for a Pre-Closure Safety Analysis of a Potential Yucca Mountain Repository

摘要

The U.S. Department of Energy (DOE) has been mandated by Congress to develop a high-level waste (HLW) repository at the Yucca Mountain (YM) in Nevada. The DOE will submit a license application to the U. S. Nuclear Regulatory Commission (NRC) for construction authorization which will contain necessary information needed by the NRC to determine whether the repository can operate safely. The pre-closure period during which the HLW will be packaged and emplaced in the repository has specific radiation protection limits as specified in 10 CFR 63. In order to systematically perform a pre-closure safety analysis (PCSA), a software program was developed by the Center for Nuclear Waste Regulatory Analyses for the NRC. This software, named the "PCSA Tool", allows the user to input information categorizing and identifying event sequences. This leads to the development of a library of event sequences and their corresponding frequencies to which estimated potential doses to the public can be added. As stated in 10 CFR Part 63, potential doses to the public are separated into two different classifications. The first is a category 1 event, which has a limit of 15 mrem/yr, and is for event sequences which are expected to occur at least once during the pre-closure period. The second is a category 2 event with a limit of 5 rem/yr and is for event sequences which have a chance of at least 1 in 10,000 of occurring during the pre-closure period.