Inspectors find safety irregularities at Creusot nuclear forge in France

An international team of inspectors has found evidence of doctored paperwork and other failings at a forge in France that makes parts for nuclear power stations around the world.

The UK nuclear regulator said the safety culture at the site, which has produced forgings for British plants including Sizewell B and the planned new reactors at Hinkley Point, fell short of expectations.

Last December regulators from the UK, US, China, Finland and Canada visited the Creusot forge run by the French state-owned nuclear builder Areva, to address their concerns after the country’s regulator ASN discovered quality-control problems and falsification of records in 2014.

A report of the inspection by the UK’s Office for Nuclear Regulation (ONR), obtained via a freedom of information request, concluded the improvement measures ordered by ASN were not yet effective.

The visit uncovered an example of an employee at the forge “amending a manufacturing record in an uncontrolled manner” as recently as September 2016, two years after similar problems were uncovered. The doctoring went undetected by Areva’s on-site quality control, Areva’s independent third-party body and inspectors from EDF.

The international inspectors also discovered the use of correctional fluid – like Tipp-Ex – at the forge’s operational control room. Correctional fluid is banned at the site, where a manager told the inspection team she regularly searched workstations for it.

Experts said the report was worrying and would damage Areva. Paul Dorfman of the Energy Institute at University College London, who obtained the document, said: “Given nuclear regulation is all about safety, this kind of language is extraordinarily damaging coming, as it does, from the UK nuclear regulator.”

Areva is already suffering serious financial problems. The company recently reported a €665m (£575m) net loss for 2016, though that is smaller than the €2bn net loss it posted in 2015.

The ONR said there was a greater quality control presence “on the shop floor” of the Creusot, and much of the top management had been replaced since ASN told it to improve. But it said the international team of inspectors “were not confident that the improvement programmes and associated remedial actions … were sufficiently resourced, prioritised and integrated in order to bring about sustained improvements in manufacturing performance and nuclear safety culture”.

The report said the UK regulator should reflect on whether EDF’s oversight of Areva was up to scratch, given it is a key supplier to the Hinkley Point C power station that EDF is building in Somerset.

The ONR told the Guardian that since the visit to Creusot it had put in place plans to ensure any forgings destined for UK reactors, including Hinkley, met UK standards.

A spokeswoman said: “Since this multinational inspection, ONR has developed its intervention plans to ensure that the licensee has in place and implements adequate management and assurance arrangements to clearly demonstrate that all components are manufactured to the required standards.

“These plans will include a series of targeted inspections and other assessments of both the licensee and the supply chain, specification of appropriate regulatory hold-points, and a targeted regulatory review at an appropriate time in the next year to assess the progress and performance of both the licensees oversight and assurance activities and the expected improvements within the supply chain.”

A spokesman for EDF said: “Steel forgings for Hinkley Point C will be manufactured to the most stringent nuclear standards which are reviewed and assessed by the independent UK regulator, the Office for Nuclear Regulation. EDF Energy also has its own inspection and quality assurance programme to provide the required confidence that the components manufactured by Areva for Hinkley Point C meet those exacting standards.”