Areva EPR reactor computers still need work-NRC

NEW YORK, July 26 (Reuters) - The U.S. Nuclear Regulatory Commission told French nuclear engineering firm Areva SA CEPFi.PA the NRC staff still had safety concerns with the computer system in its new Evolutionary Power Reactor (EPR).

In a release Friday, the NRC said the staff continued to work with Areva on the EPR design certification but could not project whether this issue would delay the reactor certification.

The NRC in the past has projected it could decide on the EPR certification by late 2011.

Two power companies are seeking to build new EPRs - Constellation Energy Group Inc CEG.N/Electricite de France's EDF.PA Constellation Nuclear at Calvert Cliffs in Maryland and PPL Corp PPL.N at Bell Bend in Pennsylvania. PPL has said the new reactor could cost up to $10 billion.

The NRC has said it expects to complete the combined operating and construction licenses for both Constellation and PPL’s new reactors in 2012.

Areva is not alone in receiving questions on new reactor designs from the NRC staff.

The NRC has said staff questions were a normal part of the certification process.

Last year, for example, the NRC questioned Westinghouse Electric Co on the safety of the shield building on an amended version of its AP1000 reactor design. Westinghouse is owned by units of Toshiba Corp 6502.T, Shaw Group Inc SHAW.N, and others.

Specifically, the NRC staff said Areva needs to “better demonstrate that each safety division in the system can perform its function without relying on information originating from outside the safety division and is protected from adverse influence from outside the division.”

The staff said Areva also needs to “better demonstrate that data exchanged between safety and non-safety divisions are processed in a manner that does not adversely affect the function of the safety division.” (Reporting by Scott DiSavino; Editing by Alden Bentley)