In an Oct. 15 letter, the U.S. Nuclear Regulatory Commission has informed Westinghouse Electric Co. that it will have to modify design of the shield building for its proposed AP1000 nuclear reactor before the agency proceeds on its certification review. The NRC letter says Westinghouse must also retest any design changes to the shield building, the structure that protects the reactor’s primary containment from weather and other impacts, to make sure the structure meets safety requirements. NRC says it won’t know if and how the required redesign could impact the AP1000 review schedule until it meets with Westinghouse. In a statement, Shaw Group, which aims to build AP1000 reactors and is teamed with Westinghouse, says it does not expect any delay in certification and expects the first AP1000 plant to operate by 2016. “Certain portions of the design have already been addressed, and this expected confirmation from the NRC now allows the remainder of items to be resolved,” says J.M. Bernhard Jr., Shaw chairman, president and CEO. “We believe all issues outlined by the NRC can be addressed from a technical perspective.”