Friday, May 10, 2013

The State-of-Play of Nuclear Safety After Fukushima

If anything set the table for the American nuclear industry’s response to the accident at Fukushima Daiichi, it was the September 11, 2001 terrorist attacks. After that event, the security of all essential infrastructure was rethought. For all kinds of power plants, an important issue was keeping them functional after a devastating attack.

What happened at Fukushima was a devastating attack, albeit one without human agency. Because of the 2001 terrorist attack, the American industry was in many ways much better prepared for such an episode than the Japanese industry; still, Fukushima presented new lessons to be learned and new ways to enhance safety. The first lesson: never let a disaster go to waste. It has a lot to teach you.

The industry and the NRC are in broad agreement on the high-priority actions that should be taken at America's reactors. The industry's Fukushima response priority has been to identify those activities that provide maximum tangible safety benefits in the shortest time and implement them first.

That’s Anthony Pietrangelo, NEI’s senior vice president and chief nuclear officer, and he gets right to plant and public safety – “provide maximum tangible safety benefits in the shortest time.” The earthquake in Japan was unpredicted, but the workers at Fukushima Daiichi were already working to bring the reactors offline when the tsunami hit. That swept away the emergency generators and other emergency equipment.

The greatest safety improvement to protect against extreme events, regardless of their cause, comes from the FLEX response strategy that the industry began implementing last year. The heart of this effort is adding more portable, backup safety equipment at each reactor. More than 1,500 pieces of equipment have been acquired or ordered, including portable generators, diesel-driven pumps and satellite phones. The additional portable equipment will provide power and water to maintain key safety functions in the absence of AC power and heat transfer capability from permanently installed safety systems. These functions are reactor core cooling, used fuel pool cooling and containment integrity.

We may say, though, that the Fukushima workers didn’t expect emergency gear to wash away. Though the FLEX equipment is stowed at the facilities in order to prevent being destroyed, what if it were anyway? How do the plant workers deal with that?

In addition to new equipment being placed at all U.S. reactors, 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, radiation protection equipment, electrical generators, pumps and other emergency response equipment to an affected site within 24 hours after an extreme event.

Of course, the world came together to offer help to the Japanese as needed and requested. Why not formalize that effort to respond to emergencies here and internationally?

In addition, the Institute of Nuclear Power Operations has upgraded its emergency response center, and the facility is operational. This center will facilitate the sharing of equipment and technical expertise whenever and wherever it is needed. Thus, between the equipment available via the regional response centers and the equipment purchased by each site, the industry will have significantly enhanced its capability to assist any site in an emergency.

INPO is the right venue for this because it already maintains a database of parts available at the various facilities.

Pietrangelo also addresses what the industry and NRC have done to deal with the most frightening aspect of a nuclear energy accident, the potential release of radiation. It is potential rather than inevitable; the goal is to keep it in the former category. The best answer is to install a filtering option well suited to the nature of each facility and the potential threats it faces, but the NRC and regulators in general tend to prefer singular solutions.

One prominent area of industry/NRC interactions of late is the NRC staff recommendation for external, filtered containment vents for boiling water reactors with Mark I and II containments. The Electric Power Research Institute concluded after intensive analysis that filtered vents aren't necessarily the most effective way to filter potential radioactive releases from fuel damage. The industry believes the optimal filtration method should be determined on a plant-specific basis. The NRC's Advisory Committee on Reactor Safeguards shares that view. The five-member Commission ultimately will decide the future course of action in this area.

If it were just the industry wanting this flexibility, one might conclude that it smells cynically of an industry wanting to go cheap, safety be damned. But no: the approach is probably not, in aggregate, the least expensive way to address filtering, but it acknowledges that a large country provides a range of potential disaster scenarios that are not the same from one to another region. That’s one thing – well, two things. More importantly, other regulatory bodies and watchdogs believe it is the correct approach, too. I’m not sure this quite rises to the level of a contention. We’ll see how it goes.

Pietrangelo makes a simple, strong case for nuclear energy.

Because the long-term fundamentals show a continued, if not growing, need for nuclear energy around the globe, it is paramount that existing facilities are operated safely even as advanced-design reactors are brought to market in the years ahead. Innovation, knowledge transfer, training, and strong safety cultures are among the elements that will define the future ability of nuclear energy technologies to help meet societal needs.

There are a lot of moving parts to this piece, written for Power Engineering. I’ve focused on some key safety points here, but there’s more, including a section on industrial preparedness and another on regulation. The whole thing is worth a careful read if you’re interested in the state of play of post-Fukushima safety planning.

For a little more background, here is NEI’s video on FLEX:

A detailed overview of the nuclear industry's FLEX approach to enhancing safety post Fukushima.

1 comment:

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Having or showing the capacity to develop into something in the future.