Duizenden scheurtjes gevonden in Belgische kerncentrale (en)

BRUSSELS - Belgium’s nuclear safety chief, Willy De Roovere, on Thursday (16 August) said there could be thousands of cracks in the reactor vessel of the ageing Doel 3 nuclear reactor situated 25 km outside Antwerp and 3 km from the Dutch border.

The inspector said the cracks are parallel to the surface of the walls and pose no immediate threat but the large number has left him concerned, reports AFP i. Repairs, he noted, would be almost impossible.

It is in the reactor vessel that the water of the main primary system flows through the core, where it is heated by the nuclear fuel.

The cracks, which possibly date back to the reactor's construction some 40 years ago, were discovered using ultra-sound during inspections in June and July.

Belgium’s nuclear regulator, the federal agency for nuclear control (FANC), said the reactor is in shutdown mode for inspections and its fuel has been discharged.

The reactor poses no threat to the population, workers or the surrounding environment, stated FANC. The agency says the cracks had only now been discovered because the ultra-sound inspection had never before been carried out.

The announcement follows a meeting in Brussels on Thursday organised by FANC along with nuclear experts from the United States, France, Switzerland, Sweden, the Netherlands, Germany, Spain and the United Kingdom.

"We are considering these flaw indications very seriously and they were the focus of the international meeting of the nuclear safety authorities held today," said the FANC in statement.

Dutch company Droogdok Maatschapij (DRM), which is no longer in business, built the Doel 3 reactor vessel. The company also built another 21 casings for other reactors around the world.

These include another one for Belgium's Tihange 2 reactor, two in The Netherlands, two in Germany, two in Spain, one in Sweden, two in Switzerland, 10 in the United States and one in Argentina, reports Belgium's Le Soir newspaper.

Belgium has since shut down the Doel 3 but aim to reportedly restart the reactor in October. Authorities also aim to shut down its Tihange 2 reactor for one week.

The vessel at Tihange 2 will undergo the same type of inspection in mid-August as the one carried out on Doel 3. Both were constructed by DRM in the 1970s, said the FANC.

"I wish to point out that Doel 3 and Tihange 2 are currently in shutdown mode and as such, there is no danger for the population, the workers and the environment," said Roovere.

Belgian passes EU i nuclear stress tests

The EU initiated nuclear stress tests on all of Europe's 143 reactors in April 2011 in the aftermath of the Fukushima disaster in March.

The tests were meant to assess whether a EU-based nuclear power plant could withstand, for instance, natural disasters such as earthquakes or terrorist attacks.

FANC submitted its peer-reviewed EU stress tests on Belgium's reactors in April 2012, two months before the cracks were discovered.

"The assessments of the robustness of the plants and situations taken into account are considered adequate. In general, the robustness of the facilities is considered satisfactory by Belgian regulatory body," says the report.

The report noted, however, that further tests are needed to truly assess the impact of earthquakes and other severe weather conditions.

FANC says the cracks were not highlighted in the stress tests because they focused solely on extreme external phenomena.

"Results of the stress tests are still perfectly valid. In any case they had an altogether different purpose," says FANC.

Belgium’s nuclear reactors are managed by Electrabel, a company of the GDF-SUEZ Energy and Services Group.