Office for Nuclear Regulation

Enforcement at Dungeness B Power Station

19 October, 2021

The Office for Nuclear Regulation (ONR) has served a formal ‘direction’ to EDF Energy Nuclear Generation Ltd requiring the company to reassess safety arrangements at Dungeness B Power Station.

A direction is formal enforcement action which allows us to direct a site operator (licensee) to take specific actions to address legal compliance shortfalls.

The enforcement action follows ONR enquiries into an event at the site in May 2021 which occurred while components were being tested in one of the reactors.

Although the reactors were safely shutdown at the time, there was a failure to control the quality of feedwater in the boiler tubes at the plant.

Boiler tubes play a key role in cooling the reactors and the quality of feedwater is tightly controlled to protect these steel components. This is done by purifying the water and adjusting its qualities by carefully adding chemicals in small amounts.

On this occasion, the failure to properly control the feedwater quality caused minor damage within the boiler tubes. However, tests show they are still within the required safety limits.

A spokesperson for ONR said: “We are satisfied that this event posed no nuclear safety risk to workers or the public, but we require the necessary improvements to be identified and made in line with the high safety standards expected at nuclear facilities.”

The direction requires EDF to review and reassess its arrangements for controlling feedwater quality at Dungeness B. The company must demonstrate a detailed schedule of improvement plans and actions to ONR by 1 December 2021.