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This report is being made pursuant to 10CFR50.72(b)(3)(v)(D), Event or Condition that could have prevented fulfillment of a Safety Function needed to Mitigate the Consequences of an Accident. During routine Instrument Maintenance Surveillance Testing (LIS-HP-205), the High Pressure Core Spray System (HPCS) minimum flow valve pressure switch set point was found outside the Technical Specification allowable value. This could have prevented the High Pressure Core Spray System (HPCS), a single train safety system, from performing its design function. This is reportable as an 8 hour ENS notification. The required actions of Technical Specification (TS) 3.5.1 were entered on 7/01/13 at 1646 (CDT) when the system was made inoperable for surveillance testing. At 1705, maintenance personnel reported minimum flow valve pressure switch set point was found at 112.6 psig, which is outside of the TS Allowable Value of greater than or equal to 113.2 psig (0.6 psig below the Allowable Value). The minimum flow valve pressure switch set point has been calibrated and was left within Technical Specification allowable values, HPCS was declared OPERABLE at 1815 on 7/01/13." The licensee has notified the NRC Resident Inspector.

• * * RETRACTION FROM STEVE CHURCHILL TO JOHN SHOEMAKER AT 1346 EDT ON 8/5/2013 * * *

The event notification was reported by LaSalle Generating Station on 7/01/2013 at 2147 EDT. This update is being provided for the purposes of retracting that notification. On July 1, 2013, during surveillance testing, the Unit 2 High Pressure Core Spray System (HPCS) minimum flow valve pressure switch setpoint was found below the Technical Specification (TS) 3.3.5.1 allowable value. HPCS was declared inoperable, and TS Required Actions (RA) were entered on July 1, 2013, at 1646 hours (CDT). Because HPCS is a single train system, an ENS report was made pursuant to 10 CFR 50.72(b)(3)(v)(D), as an event or condition that could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident. The minimum flow valve pressure switch setpoint was calibrated to within TS allowable values, and HPCS was declared operable on July 1, 2013, at 1815 hours. A post-event review determined that declaring HPCS inoperable was not required. The inoperability of the pressure switch would not have impacted the function of the HPCS minimum flow valve to automatically open as required to prevent overheating of the HPCS pump. The as-found setpoint was 0.6 psig below the TS allowable value, which would have resulted in the minimum flow valve opening slightly sooner. The inoperability would also not have prevented or delayed the automatic closing of the valve at the required system flow to assure that adequate ECCS flow is available. It should be noted that the LaSalle ECCS (Emergency Core Cooling System) LOCA (Loss Of Coolant Accident) analysis assumes that the HPCS minimum flow valve is open during an injection. TS 3.3.5.1 RA D.4 requires that the minimum flow valve pressure switch be restored to operable status within 7 days. If it cannot be restored within that time, RA G.1 requires that the supported system (HPCS) be declared inoperable, precluding extended operation with the minimum flow pressure switch inoperable. The pressure switch was re-calibrated to within TS allowable values within approximately 1 hour and 29 minutes of being declared inoperable. Therefore, the HPCS system was operable with the minimum flow pressure switch 0.6 psig out of calibration for 1 hour and 29 minutes. This event did not constitute a loss of safety function of the HPCS system, and the event was not reportable under 10 CFR 50.72(b)(3)(v)(D). The licensee has notified the NRC Resident Inspector. Notified R3DO (Lara).

During fact gathering in response to an NRC inspection inquiry, it was determined that documentation does not exist that demonstrates that the Reactor Core Isolation Cooling (RCIC) Electronic Governor Module (EGM) would be able to operate during the required Station Blackout (SBO) coping mission time at the postulated post SBO RCIC room temperature of 206.4F. Current documentation supports operation up to 150F. The EGM is a skid-mounted module that provides speed control signals for the RCIC Woodward Governor. Failure of the EGM would result in a loss of speed control for the RCIC turbine. This could result in an overspeed, underspeed or no change condition. Overspeed of the turbine would result in a mechanical overspeed trip. This device is not in the EQ program but is Augmented Quality. RCIC continues to perform its Technical Specification required functions as defined in the Bases of Technical Specification (TS) 3.5.3. The TS function is to respond to transient events by providing makeup coolant to the reactor. The RCIC Room temperatures for the postulated TS transient events is less than the currently documented component qualification temperature. The RCIC is not an ESF system and no credit is taken in the safety analysis for RCIC system operation but is retained in the TS based on its contribution to the reduction of overall plant risk per Criterion 4 of 10 CFR 50.36. The RCIC system design requirements ensure that the criteria of 10CFR50 Appendix A, GDC 33, are satisfied. Due to the lack of supporting documentation for the EGM, the beyond design basis regulatory SBO rule requirements of 10 CFR 50.63 may not be met. This condition could potentially result in an unanalyzed condition that could significantly degrade plant safety and is therefore reportable under 10 CFR 50.72(b)(3)(ii). An analysis of the RCIC Room Heat Up Rate calculation is being performed as there are conservatisms built into the calculation that when removed will result in a lower temperature than 206.4F. Additional actions in progress include, establishing appropriate protected pathways to minimize the potential for a Loss Of Off-Site Power which could result in a SBO, performance of temperature qualification testing at SBO temperatures for the EGM, and performance of an extent of condition review for remaining RCIC components to ensure temperature qualification is met for the SBO rule. In parallel with temperature qualification testing, a modification to relocate the EGM to an area outside the RCIC room that has a lower SBO profile temperature is being pursued in the event that temperature qualification is not successful. The licensee notified the NRC Resident Inspector.

• * * RETRACTION FROM D. COVEYOU TO W. GOTT AT 1427 EDT ON 8/16/05 * * *

A 8-hour notification was made on July 14, 2005, in accordance with 10 50.72(b)(3)(ii)(B), Unanalyzed condition. The report was made because documentation did not support the continued operation of Reactor Core Isolation Cooling (RCIC) Electronic Governor Module (EGM) during the required Station Blackout (SBO) coping mission. Since the initial report, the post SBO room heatup calculation was evaluated and determined that the decay heat removal function during the SBO coping mission was met. The decay heat removal function during SBO coping period is achieved by either High Pressure Core Spray (HPCS) or RCIC systems. In addition, the other RCIC functions (i.e., Remote Shutdown, and Safe Shutdown Fire) were evaluated and determined to be met. Since the RCIC functions and the decay heat removal and vessel inventory functions during the SBO coping mission were maintained, the plant was not in an unanalyzed condition and this issue is not reportable. Since the condition is not reportable EN 41844 is retracted. The licensee notified the NRC Resident Notified R3DO (K. O'Brien)