on July 2; FirstEnergy Nuclear Operating Company personnel initiated criticality on June 28. During a refueling outage that began on February 28, cracks were discovered on multiple control rod drive mechanism nozzles in the vessel head, which was a replacement with only about six years of service. The 908-MWe pressurized water reactor near Oak Harbor, Ohio, is operating under a confirmatory action letter from the Nuclear Regulatory Commission that among other things calls for the reactor to be shut down no later than October 1,2011, for the replacement of the vessel head (NN, July 2010, p. 67).
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