05000341/FIN-2007003-04
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Finding | |
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| Title | CHANGE OF REQUIREMENTS TO THE ULTIMATE HEAT SINK COOLING CAPABILITY (Section 1R21.3.b.4) |
| Description | The inspectors identified an unresolved item (URI) involving the adequacy of a 10 CFR 50.59 safety evaluation for UFSAR changes that the licensee had implemented. Specifically, the inspectors questioned the licensees basis for determining that revisions to UFSAR section 9.2.5, Ultimate Heat Sink, did not require prior NRC approval before implementation. The change concluded that the ultimate heat sink (UHS) capacity could only provide a seven days supply versus the originally approved 30-day supply without the need for a make-up water source. This issue is unresolved pending further NRC review of Fermis licensing basis for the period of time in which the ultimate heat sink needs to supply sufficient cooling capacity to the safety-related service water pumps without make-up. Description: On May 23, 1995, the licensee completed 10 CFR 50.59 safety evaluation (SE) 95-0017 that changed the period of time that the UHS needed to provide sufficient cooling capacity to the safety-related service water pumps without make-up. Before the change, the UHS was required to provide 30 days of water without make-up to the safety-related service water pumps, which includes the RHRSW pumps, the emergency equipment service water pumps, and the DGSW pumps. This safety evaluation changed this period of time requirement from 30 days to seven days. The reasons for this change, as stated by the licensee, were higher evaporation rates than originally accounted for, an added assumption of a structural crack in the UHS reservoir, and higher water level needed in the UHS reservoir due to safety-related service water pumps degradation. As a result of this evaluation, the licensee determined that the change did not involved an unreviewed safety question and therefore, it did not required prior NRC approval. The inspectors reviewed SE 95-0017 and were concerned about the adequacy of the licensees basis for determining that changes to UFSAR did not require a licensee amendment. More specifically, the inspectors were concerned that TS Limiting Conditions for Operations (LCO) stated, before the change, that a minimum water volume of 2,990,000 gallons, equivalent to an indicated water level of 25-feet, was required for each reservoir in order for the UHS to be operable. The TS basis for this LCO stated that 14 Enclosure sufficient cooling capacity was available for continued operation of safety-related equipment during normal and accident conditions. The original Fermi Safety Evaluation Report (NUREG-0798) provided the basis for this sufficient cooling capacity as 30 days of water without make-up. At the time of the change, 10 CFR 50.59 (2)(iii) stated, in part, that a proposed change, test, or experiment shall be deemed to involve an unreviewed safety question if the safety of margin for any TS basis was reduced. Following identification of this issue, the licensee entered the issue into their corrective action program as CARD 07-23998. This issue is unresolved pending further NRC review of Fermis licensing basis for the period of time required for the UHS to provide sufficient cooling capability to the safety-related service water pumps and to determine if the licensee had adequately analyzed if the changed involved an unreviewed safety question. (URI 05000341/200703-04) |
| Site: | Fermi  |
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| Report | IR 05000341/2007003 Section 1R21 |
| Date counted | Sep 30, 2007 (2007Q3) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.21 |
| Inspectors (proximate) | M Munir S Sheldon R Morris R Jones J Bozga M Jones T Hartmana Dunlopm Munir B Palagi D Passehl M Shlyamberg F Baxter C Acosta Aceved |
| INPO aspect | |
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Finding - Fermi - IR 05000341/2007003 | |||||||||||||||||||||||||
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Finding List (Fermi) @ 2007Q3
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