NRC Details Long-Term Plans for Fukushima Response

The following news article originally appeared in NEI’s Nuclear Energy Overview.

The NRC staff has outlined its plans for tackling the long-term recommendations from the Fukushima task force and its progress on high-priority items in a paper released last week. The paper also reiterates the agency’s position that 10-mile emergency planning zones are adequate.

In the paper, NRC staff also said progress on higher-priority, or Tier 1 and 2, recommendations has been significant.

“The staff’s continued high-level focus on these [high-priority] actions has ensured that steady progress has been made, with stakeholder engagement, consistent with the established schedules,” the paper said. “The staff has succeeded in performing these actions while ensuring that its efforts do not displace ongoing work of greater safety benefit, work that is necessary for continued safe operation or other existing high priority work.”

The section of the report on long-term recommendations includes details on future schedules and milestones for addressing each separate recommendation.

The NRC staff said that in some cases it would wait for more information to emerge from implementation of higher-priority recommendations before proceeding. For example, hydrogen control and mitigation would have to await analysis from high-priority activities, the staff said.

“The direction from the commission on the forthcoming … paper describing potential options for additional performance requirements for reliable … hardened containment vents (including consideration of filters) will have a definitive impact on the path forward,” the agency staff wrote. “The staff will integrate the results … into a final report that will be used to determine whether any additional regulatory action is needed to address [the recommendation on hydrogen mitigation].”

The NRC staff also clarified and reiterated its stance on certain topics including used fuel transfer and emergency preparedness zones. The NRC staff said that the 10-mile EPZ remains adequate.

“The staff believes that the existing basis for the EPZ size remains valid (including for multiunit events),” the paper said. “With regard to this recommendation, the staff plans a longer-term action that is already being evaluated.”

The staff said it would evaluate the distribution of potassium iodide beyond the 10-mile EPZ, but that analysis had shown that other methods—such as evacuation—had proven more effective at reducing exposure to radiation.

The staff also said it that it intends to confirm a long-standing agency position that both fuel pools and dry casks are safe for storing used fuel.

“There is ample regulatory basis for the current agency position that spent fuel storage is safe,” the paper said. “The staff has determined that it should confirm, using insights from Fukushima, that both spent fuel pools and dry cask storage continue to provide adequate protection, and assess whether any significant safety benefits (or detriments) would occur from expedited transfer of spent fuel to dry casks.”

The paper also provides the staff’s second update on higher-priority task force recommendations, including:

NRC staff has deferred initiating work on a rulemaking on spent fuel pool makeup capability until the staff has “gained sufficient insights from implementing the related Tier 1 requirements” on mitigating strategies and flooding and seismic re-evaluations.

A separate paper is being developed to address performance requirements for hardened containment vent systems, including the need for filters. The paper is schedule to be presented to the commission in November.

The staff is on track to issue an endorsement of guidance on seismic and flooding revaluations in November.

The staff expects to begin preparation of a request-for-information letter on other natural external hazards other than earthquakes and floods “following implementation of Tier 1 regulatory actions related to seismic and flooding hazard walkdowns and reevaluations.”