NRC CAL – NOV (White)

On November 24, 2009, the NRC issued a parallel White finding to Constellation Energy as a result of inspections at Nine Mile Point Nuclear Station Unit 2. This parallel White finding was identified during a supplemental inspection to review the licensee's evaluation of the circumstances that led to the Mitigating Systems Performance Index for the cooling water system crossing the Green to White threshold. The performance indicator crossed the threshold because of service water pump unavailability for maintenance and reliability challenges caused by a November 4, 2008 event where the licensee failed to properly control diving operations while cleaning the intake bays. The inspectors identified significant weaknesses in Constellation's causal analysis for the November 4, 2008 event. Specifically, Constellation failed to identify that the initial work controls put into place for the diving evolution, and subsequent changes made to the work scope, were inadequate and directly contributed to the event. In addition, Constellation failed to identify that governing diving procedures were not followed during the event. Based on these NRC-identified weaknesses, a parallel White inspection finding was opened to allow for the NRC's continued review of Constellation's actions to address the significant weaknesses identified during the supplemental inspection.