Switzerland’s nuclear power plants could withstand a severe earthquake without consequences for the public or the environment, according to the Swiss Federal Nuclear Safety Inspectorate.
On Monday, the nuclear watchdog announced that Switzerland’s nuclear power plants had provided proof that the cooling systems for their reactors and the associated spent uranium storage pools could resist a so-called “10,000-year” earthquake and any subsequent flooding.
They would also be able to stay well within the limit set for radiation exposure in the event of a major quake, according to the inspectorate.
The results of the evaluation confirmed that there is no reason for the five existing Swiss nuclear facilities to be taken out of service at this time, concluded the regulatory authority.
“The Swiss nuclear power plants demonstrate a high level of safety - also in international comparisons,” said inspectorate director Hans Wanner.
Although their ability to withstand an earthquake was demonstrated, all five plants were asked to provide additional information.
The results of the five installations’ ability to withstand major earthquakes are also only temporarily valid, said Georg Schwarz, head of the inspectorate's nuclear power plant division.
The regulator had instructed the five Swiss plants to provide proof of their resistance to earthquakes following the March 2011 nuclear disaster in Fukushima, Japan.
It is unclear how the report will affect the Federal Administrative Court’s March ruling to close the Mühleberg atomic plant near Bern. The judges ruled that the facility will lose its operating licence at the end of June 2013 on safety grounds.
Among the safety issues cited in the decision were the existence of fissures in the reactor’s core shroud, inconclusive evaluations of security in the event of an earthquake, and the absence of a cooling system independent of the River Aare.
In response to the Fukushima disaster, parliament last year voted in favour of a government plan to abandon the use of nuclear power in Switzerland by 2034.
Anti-nuclear campaigners have criticised the report.
The non-governmental Swiss Energy Foundation said the conclusions are contradictory and ignore results of a study commissioned by the safety watchdog in 2007.
"Today's statements by the inspectorate are based only on preliminary findings," a statement argues.
It remains unclear how well the nuclear power plants really can withstand tremors, according to the critics.
Greeenpeace described the report as ill-advised.