Pilgrim's 2010 License Amendment Request For defective Three Stage Safety Relief Valves

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Proposed License Amendment to Technical Specifications: Revised Technical Specification for Setpoint and Setpoint Tolerance Increases for Safety Relief Valves (SRV) and Spring Safety Valves (SSV), and Related Changes

March 15, 2010

The SRVs require replacement because the current two-stage Target Rock SRVs have been unreliable performers with respect to leaking while in-service and the subject of setpoint drift. SRV pilot valve leakage has led to multiple plant shutdowns and the setpoint drift problem resulted in exceeding current TS limits and numerous Licensee Event Reports (LERs). It has been determined that pilot valve leakage is due to low simmer margin and high as-found lift setpoints are due to corrosion bonding at the pilot valve disc/seat. To address current SRV performance problems, Entergy has performed extensive investigations and feasibility studies. The preferred option for correcting these problems is to replace all SRVs and SSVs during the next refueling outage. RFO-1 8 is currently planned to start on or about April 17, 2011.