The Three Mile Island and Chernobyl nuclear accidents each prompted a profound rethinking of safety requirements. But as events slipped into history, the nuclear industry, regulators and governments reassured that nuclear power was once again safe and in expert hands.
So it’s probably too early to be confident about the impact of the Fukushima accident in Japan last March. But it is clear that, as security collapsed at the Fukushima Daiichi power plant, so did the fundamental dogma of modern nuclear security: that a series of back-up and redundant security systems, combined with physical security, contradicted expert estimates. Strong enough to cause external threats, there was a catastrophic slowdown in the environment and enough to make the release of radioactivity impossible.
As the disaster’s first anniversary draws near, and supporters and opponents of nuclear power prepare to use it to outline their position, will Fukushima be a turning point for the nuclear enterprise, or will the industry be as business as ever. Will I return?
Andre-Claude Lacoste, the head of France’s Nuclear Safety Authority (ASN) in Paris, suggested in a press conference last week that things had already changed. “There will be before and after Fukushima,” he promised.
is he right? Some in the industry will always oppose the cost of tighter regulation, and short-sighted or ideological politicians and companies will continue to insist that a recurrence of Fukushima is impossible in their own backyard. But many in the nuclear industry were actually and deeply shocked to see a sequence of events at Fukushima that they believed to be impossible.
The world’s major nuclear operators are interested in establishing the cause of the disaster and learning the lessons – they know all too well that if another major accident occurs, an already struggling industry in the eyes of many will end .
For example, the World Association of Nuclear Operators has stressed the need for its members to respond properly to Fukushima, and has increased its own oversight and monitoring of plants (see Nature 472, 274 and http:// doi.org/hj5; 2011).
So for France, the world’s leading user of nuclear power and arguably the country that has suffered the most from global rejection. Last week, ASN released a report announcing comprehensive safety upgrades to all reactors in the country (see page 121). The planned multi-billion-euro improvements are part of a program of testing to assess how well the French reactors will stand up to extreme events, and how prepared the plants are to deal with a major accident.
The ASN report is written with astonishing clarity, explicitly stating that a loss of coolant or power could, in the worst cases, see reactors slow down in hours. It also lists a number of deficiencies detected during the ‘stress test’, in which certain safety aspects of the plants were found to be not up to the existing standards.
Critics would wonder why the ASN had not noticed these problems earlier, given that it is responsible for regulating plants. Others will question how the authority can reconcile its statement that France’s reactors are fundamentally safe, with the insistence that they should be upgraded on safety grounds.
But it would be a mistake to penalize France for listing its nuclear shortcomings, especially when other nations seem less enthusiastic about publicly discussing the problems with their reactors and regulations. The French report is a breath of fresh air in the post-Fukushima environment in which worldwide public reassurance has often given priority to transparent debate.
To address the (universal) dilemma of how to protect a plant from external threats such as natural disasters, ASN has come up with an elegant technological solution. The report recommends that all reactors, regardless of their perceived vulnerability, should add a ‘hard core’ layer of protection systems, with control rooms, generators and pumps housed in bunkers that far outweigh those physical hazards. , for which the plants themselves are designed. Oppose.
There will be doubts about whether France will eventually implement the new measures. The bunker concept could prove to be technically difficult, and Electricité de France – the operator of the reactors – would need to pay for systems that some in the company would probably feel is an expensive luxury.
Whatever happens in the long term, the French plans have an immediate benefit: they raise the Fukushima safety bar for other countries. Governments, regulators and companies that have yet to propose anything close to such far-reaching measures must now explain why not.