* Staff shortages at suppliers slows reactor restarts
* Regulators ASN and IRSN overwhelmed by numerous dossiers
* Bottlenecks could impact reactor restarts into 2018
* EDF shares close 10.4 percent lower after warning (Adds quotes, detail on reactors)
By Geert De Clercq
PARIS, Nov 13 (Reuters) - Bottlenecks at French utility EDF’s suppliers as well as at the French nuclear regulator are delaying the restart of several nuclear reactors and could postpone some until early next year, a source familiar with the matter said.
EDF shares fell as much as 13 percent on Monday, losing up to 4.7 billion euros in market value, after EDF warned of “lower availability of some nuclear reactors at the beginning of 2018” and dropped a long-held pledge of becoming cash-flow positive next year.
The source said that with about one third of EDF’s 58 nuclear reactors currently offline for maintenance, fuel recharging or safety investigations, the utility’s suppliers and subcontractors have so much work that they are struggling to complete the necessary works on schedule.
“Because of these bottlenecks, EDF anticipates that some of the restarts will be delayed, and this could run into the start of next year,” the source said.
The source said this might force EDF to buy power on the market, as a large part of its planned production is already sold under forward contrats.
“There are not so many specialised nuclear welders, it is not a banal skill, which means that they have to run from site to site and that some operations simply have to wait,” the source said.
Areva, EDF’s main supplier and service provider, was not immediately available for comment.
The source said regulator ASN and its technical arm IRSN were facing the same problem of having insufficient staff numbers to tackle so many dossiers in good time.
ASN declined to comment, although its director Pierre-Franck Chevet has repeatedly said his organisation needs more staff to handle the extra workload caused by an investigation into manufacturing irregularities at Areva-owned nuclear foundry Creusot-Forge.
EDF is expected to give more details about reactor restarts when it releases nine-month results late on Tuesday.
At a parliament hearing last week, Dominique Miniere, the head of EDF’s nuclear fleet, said EDF teams were working flat-out to make sure that as many reactors as possible will be available in January, usually the coldest period in winter.
He said this year’s maintenance campaign was complicated by “difficulties with competencies” at its main suppliers.
Miniere said he hoped the four reactors at Tricastin - which the ASN orded be halted pending repairs to a dike along a cooling water canal - would return to service soon.
He said EDF had completed the works at the dike and sent the dossier to the ASN, which is now reviewing it.
“One can reasonably hope for the return of these units by the end of November, but I am not in charge of the ASN calendar,” he said.
Miniere said he hoped that only two reactors -- Fessenheim 2 and Paluel 2 -- would remain offline during the coldest months of the winter, compared with four last year.
Fessenheim 2 remains under ASN investigation because of the discovery of weak spots in the steel of one of its steam generators, while work is ongoing at Paluel 2 to replace one of its steam generators, which crashed onto the reactor floor during maintenance in March 2016.
EDF shares closed 10.4 percent lower, their biggest fall since December last year. (Reporting by Geert De Clercq; Editing by Richard Lough and David Evans)