05000336/FIN-2012003-01
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Finding | |
|---|---|
| Title | Inadequate Operability Determination for 3FWS*CTV41 Feedwater Isolation Valve Hydraulic Actuators |
| Description | An NRC identified finding of very low safety significance (Green) was identified for Dominions failure to adequately assess the operability of the Unit 3 Feedwater isolation valves, 3FWS*CTV41A, B, C and D in accordance with OP-AA-102-1001, Development of Technical Guidance Basis to Support Operability Determinations, and C OP 200.18, Time Critical Operator Action Validation and Verification. Specifically, Dominion did not properly validate or credit manual operator actions to isolate the main feedwater lines during a feedline break inside containment as a compensatory measure for degraded hydraulic valve actuators. Dominion entered this issue into their corrective action program (CAP) as condition report number 478020, and conducted a reanalysis of the operability determination. The finding is more than minor because it is similar to NRC Inspection Manual Chapter (IMC) 0612, Appendix E, Examples of Minor Issues, Example 3.k; in that the inadequate assessment of operability resulted in a condition where there was a reasonable doubt on the operability of the feedwater isolation function and the feedwater isolation valves. This issue is associated with the Equipment Control attribute of the Mitigating Systems cornerstone and affected the cornerstone objective to ensure the availability, reliability and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, Dominion did not explicitly take credit for manual operator actions to trip the main feedwater pumps as a compensatory measure for the degraded capability of the 3FWS*CTV41 feedwater isolation valves to perform their safety function during a feedline break event inside containment. The inspectors determined this finding was not a design qualification deficiency resulting in a loss of functionality or operability, did not represent an actual loss of safety function of a system or train of equipment, and was not potentially risksignificant due to a seismic, fire, flooding, or severe weather initiating event. Therefore, the finding is considered to be of very low safety significance. The inspectors did not assign a cross cutting aspect to this finding because the finding was not reflective of current performance. Operability determination OD000237 was completed in 2009 and OP-AA-102-1001 does not require periodic reassessment of active operability determinations. |
| Site: | Millstone  |
|---|---|
| Report | IR 05000336/2012003 Section 1R15 |
| Date counted | Jun 30, 2012 (2012Q2) |
| Type: | Finding: Green |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.15 |
| Inspectors (proximate) | B Haagensen J Krafty J Laughlin W Raymond S Shaffer J Nicholson R Bellamy J Ambrosini O Masnyk-Bailey |
| INPO aspect | |
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Finding - Millstone - IR 05000336/2012003 | ||||||||||||||||||||||||||
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Finding List (Millstone) @ 2012Q2
Self-Identified List (Millstone)
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