Implementing Lessons Learned from Fukushima

Timeline

Key Topics

  Current Fukushima Status
     TEPCO Status Reports
     Unit 4 Spent Fuel Pool
     Stability

Filtered Vents Commission Paper

Japan Task Force Report

Japan Lessons Learned Project Directorate

NRC Response Fact Sheet

FOIAs and Operations Center Transcripts

Japan Event Overview

On Friday, March 11, 2011, a 9.0-magnitude earthquake struck Japan and was soon followed by a tsunami, estimated to have exceeded 45 feet (14 meters) in height, resulting in extensive damage to the six nuclear power reactors at the Fukushima Dai-ichi site. Upon learning of the event that morning, the NRC began monitoring the situation. Later that afternoon, the NRC activated and staffed its Emergency Operations Center at headquarters in Rockville, Maryland, to closely monitor the Japan events and assess the potential impact on U.S. nuclear plants and materials, particularly those on the West Coast and in Hawaii, Alaska, and U. S. Territories in the Pacific. The agency also began interacting with its Japanese regulatory counterparts and dispatched two experts to Japan to help at the U.S. Embassy in Tokyo. By Monday, March 14, the agency had dispatched a total of 11 NRC staff to provide technical support to the American Embassy and the Japanese government. The NRC was there to assist the Japanese government and respond to requests from its Japanese regulatory counterparts. The agency also provided support to the U. S. ambassador and the U.S. government assistance effort.

NRC Assessment of Event

Since that time, the NRC has been working to understand the events in Japan and relay important information to U.S. nuclear power plants. In particular, the NRC established a task force of senior agency experts to determine lessons learned from the accident and to initiate a review of NRC regulations to determine if additional measures needed to be taken immediately to ensure the safety of U.S. plants. The task force issued its report on July 12, 2011, which concluded that there was no imminent risk from continued operation and licensing activities. The Task Force also concluded that enhancements to safety and emergency preparedness are warranted and made a dozen recommendations for Commission consideration. The staff subsequently prioritized and expanded upon the task force recommendations (see SECY-11-0137) and continues to make additions and modifications, as appropriate:

Tier 1 Recommendations

Tier 1 Recommendations
The first tier consists of those actions which the staff determined should be started without unnecessary delay and for which sufficient resource flexibility, including availability of critical skill sets, exists.

Seismic and flood hazard reevaluations (Recommendation 2.1)

Seismic and flood walkdowns (Recommendation 2.3)

Station blackout regulatory actions (Recommendation 4.1)

Mitigating strategies for beyond design basis events (Recommendation 4.2)

Reliable hardened vents for Mark I and Mark II containments (Recommendation 5.1)

Spent fuel pool instrumentation (Recommendation 7.1)

Strengthening and integration of emergency operating procedures, severe accident management guidelines, and extensive damage mitigation guidelines (Recommendation 8)

Emergency preparedness regulatory actions (staffing and communications)(Recommendation 9.3)

Tier 2 Recommendations

Tier 2 Recommendations
The second tier consists of those actions which could not be initiated in the near term due to factors that include the need for further technical assessment and alignment, dependence on Tier 1 issues, or availability of critical skill sets. These actions do not require long-term study and can be initiated when sufficient technical information and applicable resources become available.

Spent fuel pool makeup capability (Recommendation 7.2, 7.3, 7.4, and 7.5)

Emergency preparedness regulatory actions (Recommendation 9.3)

Other External Hazards Reevaluation (tornados, hurricanes, drought, etc.)(additional Issue)

Tier 3 Recommendations

Tier 3 Recommendations
The third tier consists of those actions that require further staff study to support a regulatory action, have an associated shorter-term action that needs to be completed to inform the longer-term action, are dependent on the availability of critical skill sets, or are dependent on the resolution of NTTF Recommendation 1. The staff has focused its initial efforts on developing the schedules, milestones, and resources associated with Tier 1 and Tier 2 activities. Once the staff has completed its evaluation of the resource impacts of the Tier 1 and Tier 2 recommendations, it will be able to more accurately address the Tier 3 recommendations.

Ten-year confirmation of seismic and flooding hazards (dependent on Recommendation 2.1) (Recommendation 2.2)

Potential enhancements to the capability to prevent or mitigate seismically-induced fires and floods (long-term evaluation) (Recommendation 3)

Reliable hardened vents for other containment designs (long-term evaluation) (Recommendation 5.2)

Hydrogen control and mitigation inside containment or in other buildings (longterm evaluation) (Recommendation 6)

Emergency preparedness enhancements for prolonged station blackout and multiunit events (dependent on availability of critical skill sets) (Recommendation 9.1/9.2)

Emergency Response Data System capability (related to long-term evaluation Recommendation 10) (Recommendation 9.3)

Additional emergency preparedness topics for prolonged station blackout and multiunit events (long-term evaluation) (Recommendation 10)

Emergency preparedness topics for decision-making, radiation monitoring, and public education (longterm evaluation) (Recommendation 11)

Reactor Oversight Process modifications to reflect the recommended defense-indepth framework (dependent on Recommendation 1) (Recommendation 12.1)

Staff training on severe accidents and resident inspector training on severe accident management guidelines (dependent on Recommendation 8) (Recommendation 12.2)

Basis of emergency planning zone size (additional issue)

Prestaging of potassium iodide beyond 10 miles (additional issue)

Transfer of spent fuel to dry cask storage (additional issue)

NRC Actions in Response to Event

On March 12, 2012, based on the prioritized task force recommendations, the NRC issued the first regulatory requirements for the nation’s 104 operating reactors based on the lessons-learned at Fukushima Dai-ichi. The NRC continues to evaluate and act on the lessons learned to ensure that appropriate safety enhancements are implemented at nuclear power plants here in the U.S. In accordance with Commission direction, the NRC’s activities are being led by a steering committee comprised of senior NRC management. Additionally, the NRC established the Japan Lessons Learned Project Directorate, a group of more than 20 full-time employees focused exclusively on implementing the lessons learned.