A 40-year old Spanish nuclear power plant built to the same design model as Fukushima’s disaster-struck reactor number one has become engulfed by calls for it to be shut down, while Brussels is questioning the safety of EU installations and has pushed for stress tests of nuclear power plants.
Antonio Cornado, communications manager for Spain’s Consejo de Seguridad Nuclear (Nuclear Safety Council) regulator, confirmed to EurActiv that the Santa Maria de Garona plant, about 70 miles south of Bilbao, contains a General Electric Mark 1 Boiling Water Reactor (BWR) system, of a similar variety to that in Fukushima’s reactor number one.
“It’s the same type,” he said. “It is a Mark 1, but there are several performance [enhancements] that are better than the original design. There have been a lot of safety modifications.”
Questions about the model’s safety were “closed” 20 years ago, he added.
German MEP Jo Leinen, chair of the European Parliament’s environment committee, told EurActiv that other EU member states should follow Germany’s lead in announcing a moratorium to halt the operations of older nuclear power stations until stress tests had been carried out.
“If a Fukushima-type nuclear reactor exists in the European Union, there should be a very quick risk assessment and the necessary consequences for that type of old-fashioned nuclear power technology,” he said.
On 15 March, EU Energy Commissioner Günther Oettinger told MEPs that all European nuclear reactors would be stress-tested for their capacity to deal with disasters such as earthquakes and floods, as well as their age, construction type, back-up systems and capacity to guarantee operations.
A nuclear safety directive in July 2011 would follow the study. But Leinen urged a German-style moratorium for Spain.
“We need the same security for everybody in the European Union and not second-class security in some member states,” he said.
His words were echoed by Greenpeace’s nuclear campaigner, Jan Haverkamp. “Garona should have been closed down long ago already,” he said. “It should be switched off as soon as possible.”
Warnings over Mark 1 reactor
In the 1970s and 80s, the Mark 1 reactor faced serious criticism from US regulatory officials over its pressure containment system. A safety official with the US Atomic Energy Commission, Stephen Hanauer, recommended in 1972 that the Mark 1 system be discontinued because of its “preponderant” safety disadvantages.
In the mid-1980s, Harold Denton, an official with the Nuclear Regulatory Commission, had asserted that the Mark 1 reactors had a 90% probability of bursting if the fuel rods overheated and melted in an accident, according to a report in the New York Times.
But, according to Haverkamp, nuclear campaigner with Greenpeace, even the most modern nuclear plant would have had problems coping with the climactic disaster that hit Japan – supporting his contention that all nuclear reactors should be shut down.
Several retrofits and safety modifications were demanded by the US nuclear regulators – and commissioned by GE. These were also installed in all the BWR Mark 1 containment units at Fukushima Daiichi.
In the months ahead, investigators will doubtless try to establish whether the various upgrades were sufficient, or whether previous warnings of design flaws might need to be re-examined.
Michael Tetuan, a spokesman for General Electric, told EurActiv that it was “hard to say” if all the modifications recommended by the US regulator had been applied at Garona, but that they had been communicated.
He stressed that “during the magnitude 9.0 earthquake – the fifth largest earthquake in recorded history – the GE BWR reactors performed as designed and initiated safe shut down”.
“The reactor is safe,” he reiterated. “But we want to look at the details of what happened here. There is going to be a lot of discussion, and we’re part of that process.”
Dr Helmut Hirsch, an independent nuclear consultant, who has advised the Austrian government’s environment ministry, the German state government and Greenpeace, told EurActiv that the jury was still out on whether Harold Denton’s analysis had now been confirmed.
“There was certainly containment failure in two units in Fukushima, so this would be like a confirmation,” he said. “On the other hand, the failure was not a dramatic bursting but rather a [radiation] leakage. The failure was in a smaller way, with smaller leakages.”
The problem with the GE Mark 1 BWR reactor type, Hirsch said, was that its secondary containment structure to prevent radiation leakage “has very small volume which then can lead more easily to failure due to over-pressure”.
Spanish plant ‘operating perfectly’
In Spain though, Cornado stressed that Garona was “operating perfectly” at the moment, and that post-Fukushima safety checks would have to wait for more details of the accident to emerge.
In the meantime, there was no reason to shut the site down, he said.
“The question is not if Fukushima is similar to Garona,” he commented. “The question is if Japan is similar to Spain in risk and the answer is ‘no’.”
Standing 500m high, the reactor was taller than the one at Fukushima, and as it was further inland, “a tsunami is not possible,” he said, adding: “An earthquake so dangerous is not possible because the zone is very quiet.”
But northern Spain has experienced minor earthquakes in the past, and a tremor measuring 6.2 on the Richter scale shook Granada a year ago.
“Philosophically, that’s not a good attitude,” Dr Hirsch said, “because unexpected things can happen. There can be greater loads to the plant than we anticipated in the design”.
These could vary from heatwaves that knocked out electricity supplies, droughts that affected access to freshwater for cooling purposes, and terror attacks that targeted the Mark 1’s containment structure.
“What would be appropriate now is to really look into the robustness of the design for safety reasons,” Dr Hirsch told EurActiv.