Skip to main content

NRC Chairman Jaczko Responds to Questions from EPW Chairman Boxer on Fukushima-Daiichi

On March 17, Environment and Public Works Committee Chairman Barbara Boxer (D-CA) asked for a thorough review and posed a number of questions to the Nuclear Regulatory Commission on US nuclear power plants. Chairman Jaczko responded on April 8 (the pdf was posted on 4/15). Below are a few highlights from the letter:

1. Please identify all U.S. nuclear facilities subject to significant seismic activity and/or tsunamis.

Although we often think of the US as having "active" and non-active" earthquake zones, earthquakes can actually happen almost anywhere. Seismologists typically separate the US into low, moderate and high seismicity zones. The NRC requires that every nuclear plant be designed for site-specific ground motions that may be expected at their locations. In addition, the NRC has specified a minimum ground motion level to which all nuclear plants must be designed. The designation of the general type of seismic zone that may apply at any specific site is subject to interpretation but a conservative interpretation -meaning a larger zone-might include the following plants, based upon a preliminary estimate:

High Seismicity -Diablo Canyon, SONGS [San Onofre]
Moderate Seismicity -Brunswick, Robinson, Summer, Vogtle, Hatch, Clinton, Watts Bar, Sequoya, North Anna
Low Seismicity -all other plants

2. What extra safety features does the NRC currently require for facilities that have a credible threat of an earthquake or tsunami?

… With regard to the type of containment design used by the most heavily damaged plants in Japan, the NRC initiated a Boiling Water Reactor (BWR) Mark I Containment Improvement Program in the late 1980. This led to installation of hardened vent systems for containment pressure relief, as well as enhanced reliability of the automatic depressurization system.

Additionally, following the 9/11 events, reactor licensees have been required to develop strategies to maintain and restore core cooling, containment, and spent fuel pool cooling capabilities under the circumstances associated with the loss of large areas of the plant due to explosions or fire. Licensees are required to develop strategies for fire fighting, operations to mitigate fuel damage, and actions to minimize radiological release.

4. What increased risk is associated with exposure to mixed oxide fuel?

… NRC has evaluated the use of MOX fuel and concluded that the design basis accidents consequences were within the acceptance criteria and the differences between MOX and uranium fuel were within the dose consequences calculation uncertainties. The staff has concluded that the presence of a small number of MOX fuel assemblies in Fukushima Daiichi Unit 3 constitutes an insignificant change from non-MOX fuel in core operating conditions and accident consequences.

There are a few other answers worth checking out so be sure to stop by (pdf).

Comments

Popular posts from this blog

Wednesday Update

From NEI’s Japan micro-site: NRC, Industry Concur on Many Post-Fukushima Actions Industry/Regulatory/Political Issues • There is a “great deal of alignment” between the U.S. Nuclear Regulatory Commission and the industry on initial steps to take at America’s nuclear energy facilities in response to the nuclear accident in Japan, Charles Pardee, the chief operating officer of Exelon Generation Co., said at an agency briefing today. The briefing gave stakeholders an opportunity to discuss staff recommendations for near-term actions the agency may take at U.S. facilities. PowerPoint slides from the meeting are on the NRC website. • The International Atomic Energy Agency board has approved a plan that calls for inspectors to evaluate reactor safety at nuclear energy facilities every three years. Governments may opt out of having their country’s facilities inspected. Also approved were plans to maintain a rapid response team of experts ready to assist facility operators recoverin...

Fluor Invests in NuScale

You know, it’s kind of sad that no one is willing to invest in nuclear energy anymore. Wait, what? NuScale Power celebrated the news of its company-saving $30 million investment from Fluor Corp. Thursday morning with a press conference in Washington, D.C. Fluor is a design, engineering and construction company involved with some 20 plants in the 70s and 80s, but it has not held interest in a nuclear energy company until now. Fluor, which has deep roots in the nuclear industry, is betting big on small-scale nuclear energy with its NuScale investment. "It's become a serious contender in the last decade or so," John Hopkins, [Fluor’s group president in charge of new ventures], said. And that brings us to NuScale, which had run into some dark days – maybe not as dark as, say, Solyndra, but dire enough : Earlier this year, the Securities Exchange Commission filed an action against NuScale's lead investor, The Michael Kenwood Group. The firm "misap...

Activists' Claims Distort Facts about Advanced Reactor Design

Below is from our rapid response team . Yesterday, regional anti-nuclear organizations asked federal nuclear energy regulators to launch an investigation into what it claims are “newly identified flaws” in Westinghouse’s advanced reactor design, the AP1000. During a teleconference releasing a report on the subject, participants urged the Nuclear Regulatory Commission to suspend license reviews of proposed AP1000 reactors. In its news release, even the groups making these allegations provide conflicting information on its findings. In one instance, the groups cite “dozens of corrosion holes” at reactor vessels and in another says that eight holes have been documented. In all cases, there is another containment mechanism that would provide a barrier to radiation release. Below, we examine why these claims are unwarranted and why the AP1000 design certification process should continue as designated by the NRC. Myth: In the AP1000 reactor design, the gap between the shield bu...