05000323/FIN-2009009-01

Finding

Title

Failure to Follow Design and Configuration Control Requirements

Description

The inspection team identified a noncited violation of 10 CFR 50, Appendix B, Criterion III, Design Control, which requires licensees to implement measures to assure that applicable regulatory requirements and the design basis are correctly translated into specifications, drawings, procedures, and ins ructions. These design control measures include verifying or checking the adequacy of design, such as by the performance of design reviews, by the use of alternate or simplified calculation methods, or by the performance of a suitable testing program. Specifically, on February 16, 2008, plant engineering personnel failed to implement the design control process for a modification to the Unit 2 residual heat removal containment sump valves when they inappropriately used maintenance procedures to reduce the valve stroke leng1hs from 15.5 to 13.8 inches. The invalid design change resulted in the inoperability of both emergency core cooling trains between April 8, 2008, (when the plant entered Mode 4) and October 22,2009. The reduced sump valve stroke length also caused a portion of the sump valve disc to remain in the residual heat removal suction flow path, reducing the available residual heat removal pump net positive suction head. The licensee entered this condition into their corrective action program as Notification 50277252. The inspection team concluded that the failure of plant engineering to use the design control process was a performance deficiency within the licensees ability to foresee and correct. The finding is more than minor because it affected the Mitigating Systems Cornerstone initial design control attribute and objective to ensure the availability, reliability, and capability of systems that respond to initiating events. Using Manual Chapter 0609.04, Phase 1 - Initial Screening and Characterization of Findings, the finding required a Phase 2 analysis because the finding represented the loss of a safety system function. The Phase 2 analysis determined that this finding was potentially greater than Green; therefore, a Phase 3 analysis was completed by a regional senior reactor analyst. The Phase 3 analysis determined that this issue was of very low safety significance (Green), owing principally to the fact that operators could have opened the affected valves locally with a very high probability of success. This finding had a crosscutting aspect in the area of problem identification and resolution associated with the corrective action program component because the licensee did not thoroughly evaluate the failure of the valves to meet the specified stroke time to ensure that the resolution fully addressed the causes and extent of condition, as necessary P.1(c)

01
Site:	Diablo Canyon
Report	IR 05000323/2009009 Section 1R02
Date counted	Mar 31, 2010 (2010Q1)
Type:	NCV: Green
cornerstone	Mitigating Systems
Identified by:	NRC identified
Inspection Procedure:	IP 71111.02
Inspectors (proximate)	M Peck P Elkmann M Runyan R Caniano M Williams
CCA	P.2, Evaluation
INPO aspect	PI.2
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Finding - Diablo Canyon - IR 05000323/2009009

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)

IR 05000323/2009009: 1 2 3

Finding List (Diablo Canyon) @ 2010Q1

CCA Matrix: 2010Q1

	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-2009005-01	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
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-2009005-03	2009Q4	P.2	Inadequate 50.59 Evaluation for Steam Generator Tube Rupture Analysis
05000275/FIN-2010002-05	2010Q1	P.2	Failure to Submit a LERE for a Common-Cause Inoperability of Independent Trains or Channels
05000275/FIN-2010002-04	2010Q1	P.2	Less Than Adequate Evaluation Following a Failure of Both Motor Driven Auxiliary Feedwater Trains
05000275/FIN-2010002-03	2010Q1		Failure to Report a Condition That Could Have Prevented the Fulfillment of a Safety Function
05000275/FIN-2010002-02	2010Q1	P.2	Failure to Update the Final Safety Analysis Report with the Current Plant Design Bases
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-2010002-01	2010Q1	P.3	Failure to Effectively Implement the Seismically-Induced Systems Interaction Program
05000275/FIN-2010402-01	2010Q1		Security
05000275/FIN-2010402-02	2010Q1		Security
05000323/FIN-2009009-02	2010Q1	P.2 P.1(a)	Failure to Conduct an Adequate Post-Modification Test
05000323/FIN-2009009-01	2010Q1	P.2	Failure to Follow Design and Configuration Control Requirements

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

[Diablo Canyon Findings full list]

05000323/FIN-2009009-01

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