The nuclear energy industry and the U.S. Nuclear Regulatory Commission are in broad agreement on the actions to be taken in response to the Fukushima Daiichi nuclear plant accident in Japan. The industry's priority has been to identify those activities that provide maximum tangible safety benefits in the shortest time and implement them first.
The NRC has issued the highest priority (Tier 1) requirements related to the post-Fukushima recommendations. The industry is making excellent progress implementing those requirements along with additional steps that companies are taking proactively. Industry guidance documents to facilitate implementation of the Tier I orders were developed in 2012, and the NRC has endorsed the industry's path forward on these issues.
The design and construction of U.S. nuclear plants are robust. This enables facilities to withstand a broad range of events safely as our operating experience has demonstrated. However, the U.S. industry is taking many additional actions to assure that our plants remain safe even under extreme conditions. The greatest improvement to protect against extreme events, regardless of their cause, comes from the Diverse and Flexible Coping Strategy (FLEX) that the industry began implementing in 2012. The heart of this effort is adding more capacity and capability to assure power and water are available to maintain key safety functions. Industrywide, more than 1,500 pieces of major equipment have been acquired or ordered, including portable generators and diesel-driven pumps that can be quickly deployed by trained plant personnel. In the absence of AC power and heat transfer capability from built-in safety systems, these measures will assure that reactor core cooling, used fuel pool cooling and containment integrity are maintained. FLEX modifications at all U.S. reactors will be complete by 2016.
In addition to every reactor’s new equipment, which each power station is poised to share with another plant affected by an extreme event, the industry is developing regional response centers in Memphis and Phoenix that will serve as dispatch points for additional equipment and resources. The regional response centers will be capable of delivering another full set of portable safety equipment to a facility affected by an extreme event within 24 hours after it is requested by site personnel. The regional response centers will be operational by August 2014. The startup cost, to be shared by all U.S. companies operating nuclear energy facilities, is approximately $40 million. The shared average annual cost thereafter will total about $4 million.
STATUS OF PRIORITY ACTIONS
Plant seismic and flooding inspections to confirm safety against severe natural events.
Enhanced site emergency response capabilities: Staffing analysis (first phase); on-site communications capability and ability to make public notifications.
NRC order on mitigation strategies for prolonged loss of electricity, also known as a station blackout: Utilities have procured additional portable equipment; 20 plants will complete their FLEX preparations this fall. Two regional response centers, each housing five full sets of backup safety equipment that can be delivered to any U.S. site within 24 hours, will be in operation by August 2014
NRC order on used fuel pool cooling water level instrumentation: Design, testing and procurement of instrumentation systems; 20 plants will install pool level instrumentation this fall.
NRC order on reliable hardened containment vents (for Mark I and Mark II boiling water reactors): The original 2012 order was revised in 2013; NRC endorsed industry guidance, and designs are progressing.
Seismic re-evaluations: Re-evaluations of reactors in the central and eastern United States based in part on updated seismic models will be submitted to the NRC by end of March 31.
Flooding re-evaluations: Two-thirds of the re-evaluations will be complete by the end of 2014.
Expedited transfer of used nuclear fuel to dry storage: Final NRC decision on this issue is expected soon; NRC staff studies showed that used fuel storage pools are safe as they are operated today and recommended no action to require expedited used fuel transfer from the pools.