To restart two Belgian nuclear power plants which have been shut since the discovery of cracks in their reactor vessels could have “catastrophic consequences”, according to a new study.

The study claims to have found indications of radiation embrittlement of the reactor pressure vessel at Doel-3 plant, near Antwerp.

Yesterday Belgian Green MP Kristof Calvo told a press conference at the European Parliament: “If you have these problems in Belgium, all the other reactors [in Europe] should be checked for the same defects.”

Doel-3, along with Tihange power plant near Liege, was shut last August when Belgium’s nuclear regulator said that problems in its construction had caused a “malaise” with a large number of non-hazardous defects.

Belgium’s nuclear safety authority is expected to give the two plants a clean bill of health in a report to the Belgian government on 15 January, but no official decision on their future has yet been taken.

But the new study, commissioned by the Green Party group in the European Parliament and written by consultant Ilse Tweer, states: “A possible failure of the reactor due to sudden crack growth in case of local thermal stresses cannot be excluded and would have catastrophic consequences, especially in the vicinity of densely populated and high-economic activity areas.”

“If a melted reactor core reached the lower plenum area where steam explosions are entrained, it would sooner or later cause containment failure with the consequence of severe radioactive releases to the environment.”