By Geert De Clercq
PARIS (Reuters) - The Creusot Forge foundry unit of French nuclear group Areva, which is under judicial investigation for suspected falsification of manufacturing documentation, had recurring quality issues, according to an external audit of the firm.
The 2015 audit report by Lloyd's Register Apave, which was ordered by Areva, was published by French anti-nuclear group Sortir du Nuclear, which said it obtained it from French nuclear regulator ASN under a freedom of information request.
Areva did not immediately return a request for comment on the report, but Areva components manufacturing head David Emond said on Wednesday irregularities in its manufacturing tracking records posed no safety problems and that Areva is overhauling its quality control monitoring.
Inspection agency Lloyd's Register Apave, which interviewed Creusot staff and did audit checks in June-July 2015, said that since 2010 activities at Areva Creusot Forge have been generally well-organized and controlled.
But it added that records of internal audits from 2011 to 2014 demonstrate that there are "consistently over 40 negative quality-related findings each year", and that Creusot Forge has not carried out comprehensive root-cause analysis.
In addition, Apave said that it continued to exceed its own targets for closing non-conformance issues.
"This indicates that wider and common issues requiring management attention may not be recognized within Areva Creusot Forges," the report said.
Apave said it was not possible to reach an overall conclusion regarding activities before 2010.
"This is really worrying. It shows that the internal processes are not straight," Sortir du Nucleaire spokeswoman Charlotte Mijeon said.
Following the discovery of weak spots in the reactor vessel of a nuclear plant under construction in Flamanville, France in 2014, the ASN ordered Areva to audit its Creusot foundry.
Areva said in May 2016 that some manufacturing documentation for components made at Creusot Forge may have been falsified and launched a review of 6,000 nuclear component manufacturing files from the 1965-2013 period.
French and foreign nuclear regulators - including the U.S. Nuclear Regulatory Commission - have said that the documentation irregularities, of which Areva has informed its customers, pose no safety risk.
But utility EDF <EDF.PA> in June 2016 halted its Fessenheim 2 reactor after irregularities were found in tracking files for one of its steam generators, while in October it extended the outage of its Gravelines 5 reactor after finding a major irregularity in the control files for a new Creusot-made steam generator it was about to install.
The Paris prosecutor in December opened an investigation into suspected falsifying of documents at Le Creusot.
(Reporting by Geert De Clercq; Editing by Ruth Pitchford)