An impromptu inspection last July by the French nuclear safety authority ASN of the Areva nuclear reprocessing plant at La Hague in Normandy found that in certain areas, both explosion protection and hydrogen monitoring did not comply with established safety standards. La Hague contains the largest amount of radioactive materials on one site in the whole of the EU.
The ASN report is dated July 31 and was made available on its website on September 12.
It found that in some work areas, a backup air supply system designed to dilute the quantities of hydrogen produced from building up to levels where there was an explosion risk did not operate effectively within the specified time frame.
It also found a higher than permitted explosion risk from hydrogen buildup in tank domes containing nuclear materials.
There were also corrosion issues across the plant, according to ASN, particularly in pipework.
Areva is currently undergoing restructuring after a period of economic difficulties, and is due to be subsumed within the EDF group. A company spokesman told AFP that “an analysis had been launched with a view to implementing actions of improvement”.
The La Hague site, which reprocesses fuel from French reactors and those of a number of other countries, currently employs 2,900, excluding subcontractors.