May 13, 2011 – In the aftermath of the problems at the Japanese Fukushima Daiichi Nuclear Station resulting from the earthquake and tsunami, the NRC asked various nuclear plants in the U.S. to assess their capabilities to respond to extraordinary consequences. The plants were asked to evaluate measures to address their ability to mitigate problems from large fires or explosions; station electrical blackouts; internal and external flooding; and the impact from seismic events.
The NRC found both Peach Bottom and Berwick were in good shape for any of the listed catastrophic events.
At the Peach Bottom facility, no deficiencies were found addressing blackout conditions. On flooding events, the NRC noted that the licensee identified several minor barrier and door discrepancies, and procedural enhancements were entered into its corrective action program.
On the other issues, the NRC inspector noted that equipment was available and functional, and no significant deficiencies were identified. However, the licensee identified several enhancements needed to improve the long-term reliability of equipment and several enhancements needed to increase the survivability of portable equipment.
At Berwick, plant operator PPL identified a vulnerability in a blackout because a portable diesel generator may be unavailable for use because it is not routinely stored in a hardened building or enclosure. This problem was entered into the plant’s corrective action program. The NRC also observed that no concerns were identified from flooding events, although some issues were entered into a corrective action program.
On the other issues, certain vulnerabilities were identified in case of a major seismic event, and corrective actions are planned.
