05000458/FIN-2015004-05

Finding

Title

Failure to Follow Procedure Results in Inadvertent Draindown of Reactor Pressure Vessel

Description

The inspectors reviewed a self-revealing, non-cited violation of Technical Specification 5.4, Procedures, for the licensees failure to correctly implement procedure STP-200-0605, Remote Shutdown System Control Circuit Operability Test, Revision 307. The procedure was incorrectly performed leading to an unexpected configuration in which the reactor pressure vessel was aligned to the suppression pool, and approximately 360 gallons of reactor coolant were inadvertently transferred to the suppression pool. The licensee entered this issue into their corrective action program as Condition Report CR-RBS-2015-02354. The licensee restored compliance by restoring the system to a configuration that was consistent with plant operating procedures. Corrective actions included increased management oversight of remote shutdown system operation. The performance deficiency was more than minor, and therefore a finding, because it was associated with the Initiating Events Cornerstone attribute of configuration control, and adversely affected the cornerstone objective to limit the likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Specifically, a loss of reactor pressure vessel inventory occurred due to the establishment of an unintended system configuration caused by the inadvertent repositioning of the reactor pressure vessel suction valve. The inspectors initially screened the finding in accordance with NRC Inspection Manual Chapter 0609, Appendix G, Shutdown Operations Significance Determination Process. Using Exhibit 2 of NRC Inspection Manual Chapter 0609, Appendix G, Attachment 1, Phase 1 Initial Screening and Characterization of Findings, the inspectors determined that the finding required a Phase 2 evaluation because the loss of inventory resulted in leakage to the suppression pool that if undetected or unmitigated in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or less would cause shutdown cooling to isolate. A Region IV senior reactor analyst performed a Phase 2 evaluation of this issue and determined the issue was of very low safety significance (Green) and represented a change to the core damage frequency of 3.8E-8/year. The event sequence was an actual loss of inventory which occurred after core refueling in the shutdown. Risk was mitigated by prompt operator recovery action to stop the loss of inventory along with the operating plant configuration, which had two residual heat removal pumps aligned for automatic injection, one control rod drive pump in operation at the time of the event, and all manual injection paths fully available to mitigate the event. This finding has a cross-cutting aspect in the area of human performance associated with avoid complacency because the licensee failed to ensure that individuals recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes.

05
Site:	River Bend
Report	IR 05000458/2015004 Section 4OA2
Date counted	Dec 31, 2015 (2015Q4)
Type:	NCV: Green
cornerstone	Initiating Events
Identified by:	Self-revealing
Inspection Procedure:	IP 71152
Inspectors (proximate)	B Parks G Warnick J Sowa L Brandt L Carson M Hayes M Phalen M Stafford N Greene P Hernandez
Violation of:	Technical Specification - Procedures Technical Specification
CCA	H.12, Avoid Complacency
INPO aspect	QA.4
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Finding - River Bend - IR 05000458/2015004

1(3)2(2)3(2)4(7)5(0)6(0)7(3)8(4)9(6)10(5)301(0)401(0)402(0)403(2)405(1)406(3)409(0)501(0)

IR 05000458/2015004: 1 2 3 4 5 6 7

Finding List (River Bend) @ 2015Q4

CCA Matrix: 2015Q4

	Q	CCA	Title
05000458/FIN-2015001-01	2015Q1	H.11	Failure to Perform Adequate Operability Evaluations on Degraded High Pressure Core Spray System
05000458/FIN-2015001-03	2015Q1	H.4	Failure to Operate Condensate Demineralizer System Following Reactor Scram Results in Loss of All Feedwater
05000458/FIN-2015001-02	2015Q1	H.4	Inadequate Engineering Change and Work Instruction Review Results in Reactor Recirculation Pump Trip
05000458/FIN-2015009-01	2015Q2		Vendor and Industry Recommended Testing Adequacy on Safety-related and Safety-significant Circuit Breakers
05000458/FIN-2015009-05	2015Q2	P.2	Failure of the Plant-Referenced Simulator to Demonstrate Expected Plant Response
05000458/FIN-2015002-02	2015Q2		Failure to Maintain Design Control for 18 Upgraded Hydraulic Control Unit Accumulators
05000458/FIN-2015009-06	2015Q2	H.8	Failure to Identify and Classify Operator Workarounds that Impacted Scram Recovery Actions
05000458/FIN-2015009-04	2015Q2	H.12	Failure to Identify High Reactor Water Level as a Condition Adverse to Quality
05000458/FIN-2015009-03	2015Q2	P.2	Failure to Provide Adequate Procedures for Post-scram Recovery
05000458/FIN-2015406-01	2015Q2	H.9	Security
05000458/FIN-2015002-01	2015Q2		Inadequate Operating Margin for Reactor Protection System A Motor Generator Set for Overvoltage Protection Results in Loss of Shutdown Cooling
05000458/FIN-2015009-02	2015Q2	P.2	Failure to Establish Adequate Procedures to Perform Maintenance on Equipment that can Affect Safety-Related Equipment
05000458/FIN-2015406-02	2015Q2	H.14	Security
05000458/FIN-2015406-03	2015Q2	H.1	Security
05000458/FIN-2015008-01	2015Q3	H.1	Failure to Recognize Violations of Contamination Control Requirements as Adverse Conditions
05000458/FIN-2015008-02	2015Q3	H.9	Failure to Promptly Document Adverse Conditions in the Corrective Action Program
05000458/FIN-2015003-01	2015Q3	H.12	Failure to Operate the Unit 1 Feedwater System In Accordance With Procedures
05000458/FIN-2015405-01	2015Q3		Security
05000458/FIN-2015008-04	2015Q3	H.1	Failure to Identify an Adverse Trend in the Performance of Post Maintenance Testing on High Critical Components
05000458/FIN-2015008-03	2015Q3	H.2	Failure to Preclude Repetition of Consequential Gaps in Operator Performance
05000458/FIN-2015007-02	2015Q4		Failure to Obtain Prior NRC Approval for a Change in Reactor Core Isolation Cooling Injection Point
05000458/FIN-2015403-01	2015Q4		Security
05000458/FIN-2015004-01	2015Q4	H.8	Failure to Ensure Work Hours are Within Work Hour Limits
05000458/FIN-2015004-02	2015Q4	H.3	Failure to Properly Implement Surveillance Testing of Penetration Valve Leakage Control System Leads to Inoperability in Excess of Technical Specification Allowed Outage Time
05000458/FIN-2015004-03	2015Q4	H.5	Failure to Conduct Operations and Control Work Practices to Minimize Residual Radioactivity into the Site, including the Subsurface
05000458/FIN-2015004-05	2015Q4	H.12	Failure to Follow Procedure Results in Inadvertent Draindown of Reactor Pressure Vessel
05000458/FIN-2015004-06	2015Q4	H.8	Failure to Restore Main Steam Positive Leakage Control System to Operable Prior to Changing Modes
05000458/FIN-2015004-04	2015Q4		Failure to Make a Notification to NRC Operations Center Regarding a Radioactive Spill Reported to Another Government Agency
05000458/FIN-2015007-01	2015Q4	P.1	Failure to Establish Adequate Procedures for Severe Weather Operations

Self-Identified List (River Bend)

	Q	Title
05000458/FIN-2015003-02	2015Q3	Licensee-Identified Violation
05000458/FIN-2015007-03	2015Q4	Licensee-Identified Violation
05000458/FIN-2015004-07	2015Q4	Licensee-Identified Violation
05000458/FIN-2015403-02	2015Q4	Licensee-Identified Violation

[River Bend Findings full list]

05000458/FIN-2015004-05

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