CORTLANDT, NY — The Nuclear Regulatory Commission has decided to allow Entergy to defer seismic and flooding evaluations of Indian Point. Those evaluations are part of a series of new requirements imposed on the nation’s nuclear power plants after the Fukushima disaster in 2011.
The NRC required all U.S. nuclear power plants to perform a new evaluation of their seismic and flooding risks. Based on information developed during an initial assessment, plant owners might have had to conduct further evaluations and possibly make modifications to the facilities.
However, in January Entergy announced its intention to permanently shut down the two operating reactors at Indian Point, Units 2 and 3, in 2020 and 2021, respectively.
Subsequently, the company asked for a deferral of remaining seismic and flooding evaluations/changes in light of work that was already performed and the limited operational timeframe for the plant. On May 10, 2017, Entergy requested a deferral of the remaining seismic responses, including seismic probabilistic risk assessments (SPRAs) and spent fuel pool evaluations. On July 24, 2017, the company requested a deferral of the remaining flooding responses.
The NRC has concluded that the deferral of the remaining seismic and flooding evaluations/changes at the Indian Point nuclear power plant – until after the facility is permanently shut down — is acceptable and poses no immediate safety concerns, said spokesman Neil Sheehan.
Among other things, this is based on:
- Indian Point’s compliance with NRC post-Fukushima requirements on Mitigating Strategies for Beyond Design Basis events and enhanced spent fuel pool instrumentation. With respect to the former, the plant has acquired FLEX equipment, including portable pumps and generators, that allow it to respond to an event involving the loss of off-site power and on-site backup power. NRC inspectors are scheduled to conduct inspections in these areas before the end of 2017.
- The results and pertinent risk insights of the partially completed Indian Point 2 and 3 seismic probabilistic risk assessments (SPRAs), which were audited by NRC staff as supplemented by the staff’s independent seismic risk analysis of these sites.
- The expedited seismic evaluation process (ESEP) information for the plant, and the NRC staff assessment of the ESEP submittal
- The seismic design margin existing in nuclear power plants
- Information regarding the seismic capacity of the plant’s spent fuel pools.
- The NRC staff considered Indian Point submittals which indicated that the impact to the site from the re-evaluated flooding hazards is limited and the site is able to cope with it. Interim actions to address the re-evaluated hazards have been implemented by the company, as documented in the flooding hazard re-evaluation report and have been inspected by the staff.
- The limited timeframe for continued operation of Indian Point 2 and 3
If Entergy decides to continue to operate the units beyond 2020 and 2021, respectively, the company would need to provide the seismic and flooding information by the deferral dates approved by the NRC staff.