The U.S. Nuclear Regulatory Commission (NRC) said that components in U.S. nuclear plants made at the Creusot Forge in France that were implicated by an ongoing controversy over high-carbon concentrations and paper work irregularities had performed well and revealed no problems during safety inspections. As such, while releasing the names of the U.S. plants with Creusot manufactured components, the NRC the agency was confident the parts did not pose any safety risk.
“Our confidence is based on the U.S. material qualification process, preliminary structural evaluations of reactor components under scrutiny in France, U.S. material-aging management programs, our participation in a multinational inspection of Creusot Forge, and information supplied by AREVA about the documentation anomalies,” the agency said in a blog posting attributed to Public Affairs Officer David McIntyre.
The controversy began with the discovery of high carbon concentrations in critical components in place at the under-construction Flamanville nuclear power plant in Normandy. The follow up investigation revealed paperwork irregularities at the plant, including missing information regarding quality test results for parts that went into various reactors around the globe.
The NRC requested information about the investigation from AREVA, which was provided on Dec. 15, identifying which U.S. plants used Creusot Forge parts. AREVA, in corresponding with the agency, agreed that it was best to make the information public.
The parts, installed at 17 U.S. reactors in 13 different states, are “mostly replacement reactor vessel heads, replacement steam generator components or pressurizers,” McIntyre said.
There is, however, more information yet to come. By way of explanation: The first facet of the investigation in France involves the higher than expected concentrations of carbon that “occur naturally during the casting of steel ingots.” High concentrations imply increased brittleness or compromised toughness. “Though there are no indications it would exceed U.S. limits … we've asked AREVA if any components supplied to U.S. reactors were manufactured using that same process [that lead to problematic levels of carbon in Flamanville components] and we expect the company's answer soon,” he said.
The NRC has also conducted detailed assessments at three of the implicated U.S. reactors and found that AREVA's information on the potential problems was consisted with their own findings. “AREVA had made a reasonable assessment of no safety concerns,” McIntyre noted.
Similarly, the paperwork anomalies have yet to indicate any elevated safety concerns at U.S. plants. “We are not taking this issue lightly. Complete and accurate documentation provides assurance that components were forged to the proper procedures and specifications,” McIntyre intoned.