NRC CAL – NOV (White)

On March 26, 2015, the NRC issued a Notice of Violation associated with a White Significance Determination Process finding to Exelon Generation Company, LLC, for a violation, identified as a result of an inspection at its Dresden Nuclear Power Station, Unit 3, involving the failure to establish measures to ensure the suitability of materials, parts, equipment, and processes essential to the safety-related functions of structures, systems, and components as required by 10 CFR 50, Appendix B, Criterion III. Specifically, the licensee failed to ensure that the application of the Automatic Depressurization System electromatic relief valve (ERV) actuators, which are essential to perform the safety-related reactor vessel depressurization and overpressure protection functions, remained suitable for operation. As a result, multiple failures of the 3E ERV occurred during testing prior to operating cycle D3C23, as well as an indeterminate period of inoperability and unavailability greater than allowed by the Unit 3 Technical Specifications during operating cycle D3C23. The 3E ERV inoperability during the operating cycle was identified after the failure of the valve during its first operational test following the Unit 3 shutdown for refueling.