The two nuclear reactors were first put offline in 2012 as thousands of small cracks were discovered in the metal nuclear vessels. The reactors were out of service for 1 year, while a whole series of tests were being carried out.
They were restarted in the summer of 2013, but the nuclear watchdog FANC ordered a series of new tests to be on the safe side. These tests eventually triggered the decision to put the reactors offline again, last March. The walls of the reactor vessel showed new problems. A third series of tests was started. A final report will only be published in a couple of weeks, but the VRT found out that the first findings confirm the existing problems.
The latest hiccups mean that the two reactors will not be restarted before or during next winter, with next spring being the earliest possible date for a restart. It also turns out that there is "an increased chance that they will never be restarted again."
The company that supplied the walls of the reactor vessel, supplied similar material for 22 nuclear reactors worldwide, including 10 in the United States. Problems could emerge at these sites as well.