05000341/FIN-2013005-04
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Finding | |
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| Title | Evaluation of Apparent Unacceptable Preconditioning of High Pressure Coolant System Air Operated Valve Prior to Stroke Time Testing |
| Description | On August 26, 2013, the inspectors observed portions of surveillance test procedure 24.202.01, HPCI Pump and Valve Operability Test at 1025 PSI [Pounds per Square Inch], and subsequently reviewed the test results. This surveillance test procedure was performed, in part, to satisfy the IST Program requirements in TS 5.5.6 and 10 CFR 50.55a, Paragraph f, Inservice testing requirements. The inspectors noted that the redundant HPCI turbine supply drain pot to main condenser drain line isolation valves (E4100-F028 and E4100-F029) automatically closed when the HPCI turbine was started. These two normally open valves were required by design to close upon HPCI turbine start to isolate seismically qualified portions of the piping system from non-seismically qualified portions. The valves were verified closed at step 5.1.49 of the test procedure after the HPCI turbine was started. After the HPCI turbine was secured, E4100- F028 and E4100-F029 were then reopened at steps 5.1.104 and 5.105, respectively. At step 5.1.109, E4100-F028 was then closed and its stroke time was measured. No stroke time testing of E4100-F029 was performed since the licensee excluded the valve from its IST Program because it concluded the valve does not perform a safety function in either the open or closed position. The inspectors questioned whether the test sequence inappropriately preconditioned E4100-F028 prior to its stroke time measurement since the valve closed when the HPCI turbine started and was then manually reopened after the HPCI turbine was secured. Cycling this AOV prior to measuring its stroke time masked the as-found condition and did not appear necessary to place the system in the configuration for testing. It appeared to the inspectors that a stroke time measurement could have been performed prior to running the HPCI turbine by manually cycling the valve closed and open. In addition, the inspectors questioned the exclusion of the redundant isolation valve (E4100-F029) from the licensees IST Program since it appeared to have the same design function as E4100-F028. The inspectors noted that Inspection Manual Technical Guidance Part 9900 defines unacceptable preconditioning, in part, as: The alteration, variation, manipulation, or adjustment of the physical condition of an SSC before or during TS surveillance or ASME [American Society of Mechanical Engineers] Code testing that will alter one or more of an SSCs operational parameters, which results in acceptable test results. Such changes could mask the actual as-found condition of the SSC and possibly result in an inability to verify the operability of the SSC. In addition, unacceptable preconditioning could make it difficult to determine whether the SSC would perform its intended function during an event in which the SSC might be needed. The Part 9900 Technical Guidance further states that influencing test outcome by performing valve stroking does not meet the intent of the as-found testing expectations described in NUREG-1482, Guidelines for Inservice Testing at Nuclear Power Plants, (April 1995), and may be unacceptable. The inspectors also noted that cycling an AOV prior to performing an as-found stroke time test measurement would not be in accordance with the licensees procedural guidance. MOP03, Operations Conduct Manual, Enclosure E, Position Paper Defining the Fermi 2 Policy on Preconditioning, Revision 35, states, in part, AOVs shall be stroke timed on the first stroke of a functional surveillance test .... Basis: Timing a stroke other than the first one constitutes preconditioning because the first stroke of an air operated valve after an extended period is typically longer than the following strokes. The Part 9900 Technical Guidance states that some types of preconditioning may be considered acceptable, but that this preconditioning should have been evaluated and documented in advance of the surveillance. Since the licensee had not performed an evaluation to justify preconditioning of the valve was acceptable prior to completing the testing, the inspectors have questioned whether the licensees surveillance testing sequence that cycled the valve prior to obtaining stroke time data constituted unacceptable preconditioning of the valve. The licensee initiated CARD 13-26877 to evaluate the apparent preconditioning concern. This issue is considered to be an Unresolved Item pending additional review by the Inspectors. |
| Site: | Fermi  |
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| Report | IR 05000341/2013005 Section 1R22 |
| Date counted | Dec 31, 2013 (2013Q4) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.22 |
| Inspectors (proximate) | B Kemker J Jandovitz M Kunowski P Smagacz S Bellm Jonesm Kunowski N Adorno P Smagacz R Morris B Kemker B Palagi C Zoia J Laughlin J Nance K Carrington M Bielby |
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Finding - Fermi - IR 05000341/2013005 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Fermi) @ 2013Q4
Self-Identified List (Fermi)
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