The United Kingdom’s Office for Nuclear Regulation (ONR) issued an improvement notice to EDF Energy Nuclear Generation Ltd. earlier this month for a problem involving the pressure systems safety regulations (PSSR) at the two-unit Heysham 1 nuclear power station. The notice was served following an inspection of the Unit 1 pressure vessel at the Lancashire site.
Out of more than 600 sealed penetrations in the unit, “ONR found that EDF Energy had failed to examine 11 penetrations within the intervals specified in the written maintenance scheme,” a June 4 news release from the agency stated. ONR also concluded, however, that nuclear safety had not been compromised and that EDF Energy had “presented an adequate safety case to justify the continued safe operation of the reactor.”
A British subsidiary of France’s Électricité de France, EDF Energy must comply with the improvement notice by completing the 11 overdue examinations by December 18, 2020.
Getting noticed: ONR issued two improvement notices to EDF Energy regarding the Heysham 1 PSSR last year following a serious incident that occurred in November 2018, when a valve failed on a steam system causing injury to three of the utility’s employees. There was no release of radioactive material, and the two reactors remained operational following the incident, according to ONR. EDF was back in compliance by December 2019, the agency said.
Stats: Heysham 1’s Unit 1, a 485-MWe advanced gas-cooled reactor (AGR), entered commercial operation in July 1983. Unit 2 is a 575-MWe AGR that started providing electricity to the grid in October 1984.