05000275/FIN-2010007-05

Finding

Title

Inadequate Operability Determination Associated With the Offsite Degraded Voltage Protection Scheme

Description

On February 27, 2010, the inspectors identified a noncited violation of 10 CFR 50, Appendix B, Criteria V, \"Instructions, Procedures, and Drawings,\" after Pacific Gas and Electric failed to complete an adequate operability evaluation, as required by Procedure OM7.ID12, \"Operability Determination,\" Revision 14. The inspectors identified that the offsite power degraded voltage protection scheme time delay was inconsistent with key assumptions in the accident analysis. The licensee entered this nonconforming condition into the corrective action program as Notification 50301167 on February 24,2010. Plant operators subsequently requested plant engineering to perform an operability determination of the nonconforming condition per Operability Determination Procedure OM7.ID12. On February 27, 2010, the plant operating authority concluded that the protection scheme was operable based on the information provided in the operability determination. Contrary to the above, on March 2, 2010, the inspectors concluded that the licensee\'s operability determination was inadequate to demonstrate protection scheme operability and was not performed as required by Operability Determination Procedure OM7.ID12. Plant engineering only addressed the capability of the protection scheme at normal grid voltage following a mechanical failure of the 230kV load tap changer. Operability Determination Procedure OM7.ID12, Section 5.3, \"Write the Prompt Operability Assessment (POA),\" required that the licensee address the potential effect of the nonconforming condition to perform the specified safety function. The licensee has entered this finding into the corrective action program as Notification 50319258. Failure to complete an adequate operability evaluation, as required by Procedure OM7.ID12, \"Operability Determination,\" Revision 14, is a performance deficiency. Using Inspection Manual Chapter 0612, Appendix 8. The performance deficiency is more than minor because it is associated with the Mitigating Systems Cornerstone attribute of procedure quality. and the failure to perform an adequate operability evaluation affects the ability to ensure operability of the protection scheme at normal grid voltage following a mechanical failure of the 230kV load tap changer. The inspectors used Inspection Manual Chapter 0609. Appendix A, \"Determining the Significance of Reactor Inspection Findings for At-Power Situations,\" to analyze the finding because the violation represent the actual loss of safety function for greater than the Technical Specification 3.3.5 allowed outage time. Using Appendix M. of the \"Significance Determination Process Using Qualitative Criteria.\" the inspectors concluded that the finding was of very low safety significance (Green) based on a bounding qualitative evaluation. The inspectors based this conclusion on the low probability of an actual degraded grid condition coincidental with an accident or anticipated operational occurrence during the exposure time that protection scheme was available due to the performance deficiency. This finding had a crosscutting aspect in the area of problem identification and resolution associated with the corrective action program component because Pacific Gas and Electric did not thoroughly evaluate the nonconforming condition for operability and reportability.

05
Site:	Diablo Canyon
Report	IR 05000275/2010007 Section 1R21
Date counted	Jun 30, 2010 (2010Q2)
Type:	NCV: Green
cornerstone	Mitigating Systems
Identified by:	NRC identified
Inspection Procedure:	IP 71111.21
Inspectors (proximate)	T Farnholtz S Makor B Correll S Hedger R Kbpriva
CCA	P.2, Evaluation
INPO aspect	PI.2
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Finding - Diablo Canyon - IR 05000275/2010007

1(0)2(6)3(4)4(5)5(12)6(5)7(11)8(0)201(7)301(0)402(2)403(2)501(0)28(0)

IR 05000275/2010007: 1 2 3 4 5 6 7 8 9 10 11

Finding List (Diablo Canyon) @ 2010Q2

CCA Matrix: 2010Q2

	Q	CCA	Title
05000275/FIN-2009004-04	2009Q3	P.1 P.1(a)	Failure to Update the Final Safety Analysis Report Update with Current Accident Analysis
05000275/FIN-2009004-03	2009Q3	H.7	Failure to Follow Emergency Operating Procedures Following a Reactor Trip
05000275/FIN-2009004-02	2009Q3	P.5 P.2(a)	Failure to Perform Corrective Actions Resulted in an Unplanned Trip
05000275/FIN-2009004-01	2009Q3	P.2	Failure to Identify and Correct a Degraded Fire Barrier
05000275/FIN-2009008-01	2009Q3	H.7	Safe Shutdown Procedure Not Consistent With Safe Shutdown Analysis
05000275/FIN-2009005-04	2009Q4	P.1 P.1(a)	Less than Adequate Replacement Reactor Head Modification Design Control
05000275/FIN-2009005-03	2009Q4	P.2	Inadequate 50.59 Evaluation for Steam Generator Tube Rupture Analysis
05000275/FIN-2009005-05	2009Q4	P.2	Less than Adequate Change Evaluation to the Facility as Described in the Final Safety Analysis Report Update
05000275/FIN-2009005-01	2009Q4	H.4 H.9	Less Than Adequate Work Planning Resulted in the Release of Two Gas Decay Tanks
05000275/FIN-2009005-02	2009Q4	H.5	Failure to Properly Plan a Maintenance Activity
05000323/FIN-2009009-02	2010Q1	P.2 P.1(a)	Failure to Conduct an Adequate Post-Modification Test
05000275/FIN-2010402-02	2010Q1		Security
05000275/FIN-2010402-01	2010Q1		Security
05000275/FIN-2010002-01	2010Q1	P.3	Failure to Effectively Implement the Seismically-Induced Systems Interaction Program
05000275/FIN-2010002-04	2010Q1	P.2	Less Than Adequate Evaluation Following a Failure of Both Motor Driven Auxiliary Feedwater Trains
05000323/FIN-2009009-01	2010Q1	P.2	Failure to Follow Design and Configuration Control Requirements
05000323/FIN-2009009-03	2010Q1	P.2	Failure to Evaluate a Change to the Facility as Described in the Final Safety Analysis Report Update Associated with the Addition of Manual Actions in the Safety Analysis
05000275/FIN-2010002-02	2010Q1	P.2	Failure to Update the Final Safety Analysis Report with the Current Plant Design Bases
05000275/FIN-2010002-03	2010Q1		Failure to Report a Condition That Could Have Prevented the Fulfillment of a Safety Function
05000275/FIN-2010002-05	2010Q1	P.2	Failure to Submit a LERE for a Common-Cause Inoperability of Independent Trains or Channels
05000275/FIN-2010007-08	2010Q2	P.2	Inadequate Drawings and Procedures to Align Emergency Makeup Water Supply from Diablo Canyon Creek to Support the Auxiliary Feedwater System
05000275/FIN-2010003-02	2010Q2		Inadequate Corrective Actions Following Identification of a Nonconservative Technical Specification
05000275/FIN-2010003-03	2010Q2	P.2	Failure to Report a Condition that Could Have Prevented the Fulfillment of a Safety Function
05000275/FIN-2010007-01	2010Q2	H.14	Less than Adequate Change Evaluation to the Facility as Described in the Final Safety Analysis Report Update
05000275/FIN-2010007-07	2010Q2		Nonconservative Inputs into Motor Operated Valve Calculation
05000275/FIN-2010007-06	2010Q2		Second Level Undervoltage Relay Time Delay to Initiate Load Shed and Sequencing Upon the Diesel Generator is Adequate to Assure Plant Safety
05000275/FIN-2010007-05	2010Q2	P.2	Inadequate Operability Determination Associated With the Offsite Degraded Voltage Protection Scheme
05000275/FIN-2010007-03	2010Q2	H.14	Non-Conservative Decision Making resulted in a Violation of Technical Specification
05000275/FIN-2010007-02	2010Q2	P.2	Failure to Adequately Evaluate Changes to the Diesel Testing as Described in the Final Safety Analysis Report Update
05000275/FIN-2010007-04	2010Q2	P.2	Failure to Update the Final Safety Analysis Report Update with the Current Plant Design Bases Section
05000275/FIN-2010007-09	2010Q2		Failure to Update Feedwater Rupture Accident Analysis in the Final Safety Analysis Report Update
05000275/FIN-2010007-10	2010Q2		Failure to Update Text to Reflect Credited Design Class I Makeup Flowpath to Component Cooling Water Expansion Tank in the Final Safety Analysis Report Update
05000275/FIN-2010003-01	2010Q2	P.2	Failure to Perform Unit 1 Containment Concrete Inspections

Self-Identified List (Diablo Canyon)

	Q	Title
05000275/FIN-2009403-01	2009Q4	Licensee-Identified Violation
05000275/FIN-2009005-06	2009Q4	Licensee-Identified Violation
05000275/FIN-2010002-06	2010Q1	Licensee-Identified Violation
05000275/FIN-2010007-11	2010Q2	Licensee-Identified Violation
05000275/FIN-2010003-04	2010Q2	Licensee-Identified Violation

[Diablo Canyon Findings full list]

05000275/FIN-2010007-05

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