05000412/FIN-2015007-03
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Finding | |
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| Title | Unit 2 Alternative Post-Fire Shutdown Procedures Deficiencies for Some Postulated Spurious Operations |
| Description | The team identified a finding of very low safety significance (Green) of BVPS Unit 2 License Condition 2.F, Fire Protection Program, for failure to implement and maintain all aspects of the approved FPP. Specifically, FENOCs alternative post-fire safe shutdown operating procedures for some postulated fire-induced spurious circuit operations did not provide adequate guidance to ensure that; (1) the charging system flow path was established for reactor coolant system (RCS) makeup; (2) service water was provided for emergency diesel generator (EDG) cooling; and (3) reactor coolant pump (RCP) seal injection flow was secured prior to reinitiating charging flow beyond a ten minute lapse to preclude a RCP seal loss of coolant accident (LOCA). This issue was determined to satisfy the criteria specified for the exercise of enforcement discretion for plants in transition to a fire protection program that meets the requirements of 10 CFR 50.48(C), National Fire Protection Association Standard NFPA 805. In response to a significant fire in the Unit 2 fire areas CB-1 (Instrument Relay Room), CB-2 (Cable Spread Room), CB-3 (Control Room), CB-6 (Control Building West Communication Room), and CT-1 (Cable Tunnel), control room operators would implement the 2OM-56C.4 series procedures. These procedures are collectively the alternative post-fire safe shutdown procedure. As directed by the alternative post-fire safe shutdown procedure, control room operators relocate to the alternate shutdown panel (ASP) to establish and maintain post-fire safe shutdown. The team reviewed these procedures and identified that procedures, specifically, 2OM-56C.4.B - Unit Supervisor Procedure, Rev. 32 effective October 21, 2014, 2OM-56C.4.F-1 ASP Activation, Rev. 12 effective March 2, 2007, and 2OM-56C.4.D -Nuclear Operator #1 Procedure, Rev. 24 effective October 21, 2014, did not provide adequate guidance to ensure that the alternative shutdown performance goals would be maintained considering some postulated fire-induced spurious operations. The team identified three deficiencies within these procedures: 2OM-56C.4.D directed operators to use a charging system flow path to establish RCS makeup that was not free of fire damage for associated alternative shutdown fire areas; 2OM-56C.4.F-1 did not have adequate steps to verify the 21A service water pump was operating and adequate service water cooling flow established to the 2-1 EDG; and, 2OM-56C.4.B did not have sufficient precautions or steps to preclude a RCP seal LOCA. The charging system flow path procedure errors occurred when FENOC made procedure changes effective October 21, 2014 to 2OM-56C.4.D to address a corrective action item for terminating a fire-induced spurious safety injection signal. FENOC inappropriately assumed a B train motor operated safety injection valve, 2SIS-MOV867B, would remotely operate open, but for the associated fire areas, its cables were subject to fire damage and the valve cannot be relied on to open. FENOC promptly initiated CR-2015-10757 and revised 2OM-56C.4.D to include a local operator manual action, consistent with the fire safe shutdown analysis, to establish charging flow for RCS makeup. The adequate service water flow for the 2-1 EDG procedure errors occurred because 2OM-56C.4.F-1 provided a table that included required positions for components on the ASP and did not specify alignment order or provide any precaution to verify adequate service water flow to the 2-1 EDG after it was started. The 21A SWP switch alignment was listed third in the table and the 2-1 EDG switch alignment was listed sixth in the table. For a LOOP scenario, the 21A SWP cannot be started until the 2-1 EDG is successfully started and its output breaker closed to the 4 kV vital bus. Additionally, during control room abandonment and relocation to the ASP, the 21A SWP could spuriously operate while the 2-1 EDG auto starts. For this scenario, the procedure lacked sufficient precaution to ensure service water flow was restored from the ASP in a timely manner. FENOC promptly initiated CR-2015-1116 for long term resolution and issued Standing Operating Order 15-006 that the 2-1 EDG may not auto start and load during ASP activation. The potential for a RCP seal LOCA during execution of 2OM-56C.4.B can occur during a loss of offsite power scenario if the charging pump auto starts when the 2-1 EDG is started from the ASP and more than ten minutes has elapsed since RCP seal cooling was lost. 2OM-56C.4.B lacked sufficient precautions and procedure steps for local operator manual actions to ensure a RCP seal LOCA did not occur during the postulated LOOP scenario. FENOC promptly initiated CR-2015-11044 for long term resolution as part of transition to NFPA 805 and established interim compensatory measures in the form of fire watch patrols in the fire areas where these circuit interactions could occur. For all three post-fire alternative safe shutdown procedure deficiencies, the team concluded that FENOCs immediate and long term corrective actions were appropriate and commensurate with the risk significance. Analysis. Failure to ensure that the alternative post-fire safe shutdown operating procedures for some postulated fire-induced spurious circuit operations provided adequate guidance to ensure that; (1) the charging system flow path was established for RCS makeup; (2) service water was provided for EDG cooling; and (3) RCP seal injection flow was secured prior to reinitiating charging flow beyond a ten minute lapse to preclude a RCP seal LOCA is a PD. This PD is more than minor because it is associated with the external events (fire) attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective of ensuring the reliability and capability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). FENOC reviewed the post-fire alternative safe shutdown procedure deficiencies and evaluated the issues through use of its fire PRA. FENOC determined that the change in core damage frequency attributed to the procedure issues was 1.9E-8 (Green). NRC staff reviewed this evaluation and concluded that the risk number was bounded by conservative assumptions and that this issue would be of no greater than very low safety significance. Cross-cutting aspects are not applicable to findings involving enforcement discretion. Enforcement. Beaver Valley Unit 2 License Condition 2.F requires in part that FENOC shall implement and maintain in effect all provisions of the approved fire protection program as described in the Final Safety Analysis Report (FSAR). BVPS Unit 2 Updated FSAR, Rev. 21, Section 9.5.1.1 states that the fire protection system is designed using the guidance of BTP CMEB 9.5-1, Rev. 2. BTP CMEB 9.5-1, Rev. 2, Section C.5.c.(3) requires that the alternative shutdown capability shall accommodate post-fire conditions where offsite power is available and where offsite power is not available for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and procedures shall be in effect to implement this capability. Contrary to above, since March 2, 2007, FENOC has not had procedures in effect to implement alternative shutdown capability that accommodates post-fire conditions where offsite power is available or is not available for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Specifically, the BVPS Unit 1 alternative post-fire safe shutdown procedures did not ensure that: (1) RCS makeup function was established; (2) service water cooling was provided to the 2-1 EDG; and (3) the RCP seal injection flow was isolated to preclude a RCP seal LOCA. FENOC is in transition to NFPA 805 and therefore this NRC-identified violation was evaluated in accordance with the criteria established by Section A of the NRCs Interim Enforcement Policy Regarding Enforcement Discretion for Certain Fire Protection Issues (10 CFR Part 50.48) for a licensee in NFPA 805 transition. Specifically, because all of the criteria were met, the NRC is exercising discretion and not issuing a violation for this issue. |
| Site: | Beaver Valley  |
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| Report | IR 05000412/2015007 Section 1R05 |
| Date counted | Sep 30, 2015 (2015Q3) |
| Type: | Violation: Green |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.05 |
| Inspectors (proximate) | C Cahill D Orr J Patel J Rady J Rogge S Galbreath |
| Violation of: | 10 CFR 50.48 License Condition - Fire Protection |
| INPO aspect | |
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Finding - Beaver Valley - IR 05000412/2015007 | |||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Beaver Valley) @ 2015Q3
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