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Tag Archives: Fukushima

Taking a Look at an Independent Review of Spent Fuel Pool Safety and Security

Scott Burnell
Public Affairs Officer

 A recently published National Academy of Sciences report includes the academy’s latest thoughts on enhancing the safety and security of spent nuclear fuel storage. The NRC gave NAS the funding for the study at the direction of Congress. This report is Phase 2 of the NAS work; we’ll recap Phase 1 in a moment.

The agency sponsored the two-phase NAS study to identify lessons learned from the Fukushima accident and to follow up on previous NAS recommendations on spent fuel safety and security. The earlier NAS work looked at these same topics after the Sept. 11, 2001, terrorist attacks, and led to a 2004 report (our response to Congress about the 2004 report is on the agency’s website).

As the NAS gathered information for the latest report, they talked with NRC staff and received NRC documents related to relevant regulatory programs and requirements.

Our first look at the Phase 2 NAS report did not identify any safety or security issues that would require immediate action by the NRC. U.S. nuclear power plant security is extremely robust; the plants are some of the best protected facilities in the world. We have a long record of studying and analyzing the safety and security of spent fuel storage. Some of these studies have resulted in security enhancements. For example, after the 9/11 terrorist attacks, the NRC’s security assessments resulted in improvements to security at nuclear power plants, and strengthened the plants’ coordination with other federal and state agencies in responding to security threats.

Our post-Fukushima requirements for U.S. reactors have enhanced spent fuel pool safety. For example, we required plants to improve the ability of operators to monitor the water level in spent fuel pools. We also required plants to develop new strategies for adding water to these pools to keep them cool, even under the conditions that might exist following an extreme natural event, like a severe earthquake or flood.

Looking at all the available information, we remain confident U.S. spent fuel is safely and securely stored. The Phase 2 NAS report looks ahead to some areas that NAS believes warrant further study or action. We’ll evaluate the NAS report and its recommendations to see if we need to take any further action in the long run. The staff plans to provide the Commission with its assessment of the NAS Phase 2 report later this year.

We know the public has questions about safely and securely storing spent nuclear fuel, so the NRC website includes key points and frequently asked questions and answers. We expect to update this information once we’ve finished assessing the NAS report.

We looked at the NAS Phase 1 report in 2014. That report looked at the causes of the Fukushima accident and also identified lessons for improving nuclear power plant safety systems and operations. The staff provided the Commission an assessment of the Phase 1 report in SECY-15-0059. In our final assessment of the Phase 1 report, we determined that all of the NAS recommendations were being addressed by completed and ongoing NRC activities.

NRC Actions Stack up Well Against International Reviews

William Orders
Senior Project Manager
Japan Lessons Learned Division

Ever since the March 2011 nuclear accident at Japan’s Fukushima Daiichi plant, regulators around the world have asked “what have we learned?” The Fukushima accident led the nuclear power industry worldwide to reconsider how we approached nuclear safety in the case of extreme natural events. Regulators and the nuclear industry have put a high priority on addressing the accident’s lessons and implementing safety enhancements.

Last year, the United Nations’ International Atomic Energy Agency, issued a report that took another look at the accident and detailed what was learned. The NRC has reviewed the report to see if it might lead us to additional actions here in the United States.

At this point, we see that either the NRC, the U.S. government, or the nuclear industry are already addressing the IAEA report’s lessons. U.S. actions on these lessons are consistent with the international community’s approach to the issues. A more detailed comparison of the report’s recommendations with relevant U.S. actions is available here.

JLD vertical CReviews of the accident have focused on the effects of earthquakes and floods, as well as positioning plants to deal safely with a complete loss of off-site and back-up power. Nuclear power plants worldwide are addressing these issues with steps that include:

  • re-examining external hazards,
  • improving electrical systems,
  • adding ways to cool the fuel in the reactor core,
  • protecting the reactor containment,
  • adding ways to cool the  spent fuel in storage pools, and
  • developing capabilities to quickly provide equipment and assistance from on-site or off-site emergency preparedness facilities.

The NRC and our international counterparts have compared our post-Fukushima approaches before. In 2014, an IAEA team report looked at several of the lessons the NRC has learned from the accident. The report, after examining our efforts at that time, concluded the NRC has “acted promptly and effectively.” The team also said the NRC’s inspections on Fukushima-related issues were “exemplary.”

As the NRC continues reviewing the IAEA 2015 report in detail, we are heartened that our international counterparts are all addressing the same concerns. Our collective actions are enhancing safety worldwide.

More information on the NRC’s response to the Fukushima accident can be found on NRC’s Japan Lessons Learned website. A description of the accident is available here.

Considering Plant Circumstances for Post-Fukushima Requirements

Lauren Gibson
Project Manager
Japan Lessons-Learned Division

When the NRC establishes a new requirement or asks its licensees for information, the agency sets appropriate deadlines. Plants usually meet those deadlines, but sometimes there are complications and a licensee needs more time than was originally anticipated.

The NRC established such deadlines for its post-Fukushima actions and, in some cases, licensees have asked for more time to complete the work. For instance, a plant might need information from the U.S. Army Corps of Engineers to finish reevaluating its flooding hazard.

JLD vertical CWhat happens if the U.S. Army Corps of Engineers is still working on that information as the NRC’s deadline approaches? Another plant might be nearing compliance with all aspects of the Mitigating Strategies Order, but unforeseen prolonged and severe winter weather causes construction delays with the equipment storage building.

Other plants have announced that they will be shutting down in a few years, but after some deadlines for Fukushima-related work will have passed. What do all these plants do? They formally ask the NRC to revise the plant’s deadlines or relieve the plant of its requirement.

The NRC considers many things when reviewing these schedule change requests, including:

  • Has the plant adequately justified its request?
  • Is the amount of extra time requested reasonable?
  • How will the plant continue to ensure safety in the period between the initial and proposed due dates?

If a licensee does not provide enough information for the NRC to make a decision, it will either request additional information from the licensee or deny the request. The NRC takes extension requests very seriously and ensures that each is thoroughly reviewed – by project managers, technical experts, NRC lawyers and enforcement experts, and NRC management (in some cases, up to the Director of the Office of Nuclear Reactor Regulation).

Plants that are permanently shutting down have other options. Depending on the timing of their shutdown, they may request that NRC orders requiring certain actions be cancelled or rescinded for them. The NRC will only rescind an order after the plant has certified it has permanently ceased operations and is no longer an operating reactor. This ensures the requirements stay in place if the plant later decides to keep operating.

Plants can also ask to delay certain work on the orders, which was the case for the recently-approved Oyster Creek relaxation request. The delay is not indefinite, though. If Oyster Creek does not shut down as planned, it must complete the work by a specified date.

Plants would follow a similar process to ask for schedule relaxations on the information requests (for example, the Vermont Yankee licensee requested to be relieved of responding to the request once the plant was shut down).

All of these requests get plenty of NRC review time. The NRC staff carefully considers each request on a plant-specific basis, and the NRC would only approve a relaxation request if a licensee provides good justification and demonstrates that safety would be maintained if the request were approved.

Even with the limited number of relaxation requests approved by the NRC, the industry is well on its way to appropriately implementing all post-Fukushima safety enhancements.

 

 

Plenty of Progress to Report on Fukushima-related Enhancements

Scott Burnell
Public Affairs Officer

fukushimaThe NRC’s technical staff, industry executives and a public interest group will brief the Commissioners Thursday on the agency’s efforts to implement what we’ve learned from the Fukushima nuclear accident. The bottom line is the NRC is ahead of schedule on several fronts.

Some of the best news involves U.S. reactors meeting requirements from two of the NRC’s Fukushima-related Orders issued in March 2012. By the end of this spring, almost a quarter of the U.S. fleet will comply with the Mitigation Strategies and Spent Fuel Pool Instrumentation Orders. We expect more than half the fleet will meet those Orders by the end of December, which is a full year before the Orders’ deadline.

Every U.S. reactor will comply with the instrumentation requirements by the December 2016 deadline. Every reactor will also comply by that time with a major Mitigation Strategies requirement – additional, well-protected onsite portable equipment to support key safety measures if an extreme event disables a plant’s installed systems. The U.S. industry has already set up two response centers with even more equipment that can be transported to any U.S. reactor within 24 hours. By the time we say good-bye to 2016, almost every reactor will also have made all modifications needed to use those portable systems. In preparing to meet the deadlines, U.S. reactors have already enhanced their ability to keep the public safe.

About a dozen plants will have made all those modifications except changes closely related to the third Order, which requires Hardened Vents for reactors with designs similar to those at Fukushima. These vents would safely relieve pressure in an emergency and help other systems pump cooling water into the core. All the reactors subject to the Order have completed plans for the first set of vent enhancements or installation of new vents.

The NRC staff finished reviewing these plans earlier this month, ahead of schedule, and issued written evaluations to each plant. The agency is also about ready to issue guidance on how these plants can meet the second part of the Order, which involves an additional vent or other methods to protect the structure surrounding the reactor.

The staff’s presentation will also cover topics including revising the NRC’s rules in these areas, as well as the ongoing effort to re-evaluate flooding hazards for all U.S. nuclear power plants. The NRC’s regional offices will provide their perspective on the overall implementation effort’s progress.

Documenting a Sobering Trip to Fukushima

Scott Burnell
Public Affairs Officer

Reflections on FukushimaAs we mentioned on the blog last year, senior NRC leaders visited the site of the Fukushima nuclear accident and the surrounding area. Now, the agency has published a report that includes essays on what the team members learned. The report helps ensure current and future NRC staff can benefit from the team’s experience in the future.

The group included managers from the agency’s reactor oversight, research and emergency preparedness programs. They make up most of the agency’s Fukushima Steering Committee, which guides the staff’s implementation of what we learned from the accident. They also take active roles in ensuring U.S. nuclear power plants are prepared to deal with events similar to what happened at Fukushima experienced.

It’s clear from the team members’ essays that the visit affected them deeply. For example, Bill Dean (now director of the NRC’s Office of Nuclear Reactor Regulation) was Administrator of the NRC’s Region I office outside Philadelphia when he took part in the trip. “Most importantly, it enabled us to observe firsthand the far-reaching impacts of a nuclear disaster—not only its physical effects on the facility and the surrounding countryside but also its impact on a nation’s psyche and its people,” Dean writes. “What resonated with each and every one of us is that we cannot allow a Fukushima-like event to occur in the United States.”

Marc Dapas, Adminstrator of the Region IV office in Arlington, Texas, reflects on discussing the accident with plant staff at Fukushima. “Hearing these TEPCO employees describe what they faced and then seeing the actual physical configuration of equipment at the Fukushima sites left an indelible impression on me regarding the importance of being prepared for the unexpected,” Depas writes. “In that context, I considered the safety measures and enhancements that the NRC has required … The key in my view is to ensure that these safety measures are rigorously implemented and maintained.”

The team’s visit covered both the damaged Fukushima Dai-ichi plant and the nearby Fukushima Daini plant, which safely withstood the 2011 earthquake and tsunami. The visit also covered Kashiwazaki-Kariwa, a nuclear power plant on Japan’s west coast that survived a strong 2007 earthquake.

You can read the essays from Dean and the other trip participants in the report, and you watch a summary video about the trip on the NRC’s YouTube channel.

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