Mitigation of Beyond-Design-Basis Events
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In early 2014, NRC staff proposed that certain post-Fukushima rulemaking activities be combined for a number of recommendations made in the NTTF report. On July 9, 2014, the Commission approved the consolidation and the effort was re-named "Mitigation of Beyond-Design-Basis Events." The scope includes the Onsite Emergency Response Capabilities and Station Blackout Mitigating Strategies work described below, as well as NTTF recommendations 9.1, 9.2, and 9.3 with one exception (maintenance of ERDS capability throughout the accident), 9.4 Emergency Response Data System (ERDS) (modernization only), 10.2, and 11.1. Consolidating SBOMS and onsite emergency response capability rulemakings includes consolidation of supporting implementation guidance. The final rule schedule remains unchanged; the final rule package is due to the Commission in December 2016.
- Consolidation of Post-Fukushima Rulemaking Activities (SECY-14-0046 enclosure 6) is available in ADAMS at ML14064A544 (April 17, 2014); Approval of Consolidation (SRM-SECY-0046) at ML14190A347 (July 9, 2014).
Station Blackout Mitigation Strategies (SBOMS)
At Fukushima, the earthquake and tsunami disabled both external and internal electrical power systems, leaving the plants with only a few hours' worth of battery power. Since nuclear power plants need electrical power to keep their reactor cores and spent fuel pools cool, this loss of internal and external power—known as a station blackout (SBO)—was a significant challenge to workers at Fukushima. The Mitigation of Beyond Design Basis Events rulemaking will permanently write into the agency's rules the requirements already imposed by the Mitigation Strategies Order that was issued by the NRC on March 12, 2012. The eventual rule will ensure that if a plant loses power, it will have sufficient procedures, strategies, and equipment to cope with the loss of power for an indefinite amount of time.
- All related documents are available in Docket NRC-2011-0299 on Regulations.gov
- Consolidation of Mitigation Strategies Order, SBOMS Rulemaking, and Spent Fuel Pool Makeup Capability (COMSECY-13-0002) (January 25, 2013); Approval of Consolidation (SRM-COMSECY-13-0002) (March 4, 2013)
Learn more about the NRC's rulemaking process.
Onsite Emergency Response Capabilities
At Fukushima, the combination of several severe events challenged the plants' emergency plans and procedures. The NRC is rewriting its rules to strengthen and integrate the various emergency response capabilities at U.S. nuclear power plants. Currently, U.S. plants may have several categories of response procedures that they draw upon, depending on the incident at their site. The Mitigation of Beyond Design Basis Events rulemaking will establish standards that ensure the plants can smoothly transition between the various procedures, keeping the plants' overall strategies coherent and comprehensive. The new rule will also have the plants improve strategies for large-scale events to promote effective decision-making at all levels. The new rule will also include training, qualification, and evaluation requirements for the key personnel expected to implement the procedures and strategies.
- All related documents are available in Docket NRC-2012-0031 on Regulations.gov