By Olivia Bugault and Max Bernhard
French utility Electricite de France SA (EDF.FR) shares plunged on Tuesday morning after its majority-owned business Framatome found anomalies in its manufacturing of nuclear-reactor components.
At 0816 GMT, shares in EDF were down almost 6.6% at 10.14 euros ($11.18), the biggest loser on France's SBF 120 index.
EDF said the anomalies concern components that are currently in service as well as ones which haven't yet been installed, and that it has been conducting in-depth investigations to identify affected parts and reactors and to "ascertain their fitness for service."
An EDF spokesman declined to provide the names of the plants impacted by the anomalies. The shut down of a nuclear reactor is an option but not the preferred one, he said.
EDF, which is largely owned by the French state, said it informed France's nuclear regulatory authority of its initial investigations on Monday.
The company has had problems with a number of its nuclear reactors recently. Last year, it suspended operations at its Hunterston B plant in the U.K. after engineers discovered cracks in some of the reactors' graphite cores. The plant was approved to restart operations last month. In July, EDF pushed back the planned completion date for a nuclear plant in Flamanville in the north of France by another three years after finding problems with the welds inside the reactor. The plant was initially due for completion in 2012.
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