Light Water Reactor Sustainability Program Reactor Safety Technologies Pathway Technical Program Plan

Abstract

In the aftermath of the March 2011 multi-unit accident at the Fukushima Daiichi nuclear power plant (Fukushima), the nuclear community has been reassessing certain safety assumptions about nuclear reactor plant design, operations and emergency actions, particularly with respect to extreme events that might occur and that are beyond each plant's current design basis. Because of our significant domestic investment in nuclear reactor technology (100 operating reactors in the fleet of commercial light water reactors (LWRs) with four under construction), the United States has been a major leader internationally in these activities. The U.S. nuclear industry is voluntarily pursuing a number of additional safety initiatives. The U.S. Nuclear Regulatory Commission (NRC) continues to evaluate and, where deemed appropriate, establish new requirements for ensuring adequate protection of public health and safety in the occurrence of low probability events at nuclear power plants; (e.g., mitigation strategies for beyond design basis events initiated by external events like seismic or flooding initiators). The Department of Energy (DOE) has also played a major role in the U.S. response to the Fukushima accident. Initially, DOE worked with the Japanese and the international community to help develop a more complete understanding of the Fukushima accident progression and its consequences, and to respond to various safety concerns emerging from uncertainties about the nature of and the effects from the accident. DOE research and development (R&D) activities are focused on providing scientific and technical insights, data, and analyses methods that ultimately support industry efforts to enhance safety. These activities are expected to further enhance the safety performance of currently operating U.S. nuclear power plants as well as better characterize the safety performance of future U.S. plants. In pursuing this area of R&D, DOE recognizes that the commercial nuclear industry is ultimately responsible for the safe operation of licensed nuclear facilities. As such, industry is considered the primary "end user" of the results from this DOE-sponsored work. vi ACKNOWLEDGEMENTS Successful preparation of this report required input and support from several individuals and organizations. To get a clear industry perspective, various nuclear industry organizations provided substantial in-kind contributions by providing technical experts to participate in this process at meetings