05000413/FIN-2005002-02
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Finding | |
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| Title | Inadequate 10 CFR 50.59 Documentation |
| Description | The inspectors identified a non-cited violation for making a change to the facility (implemented as a change to the UFSAR in 1995) that involved an Unreviewed Safety Question (USQ), for which no written evaluation provided an adequate bases for the determination that the change did not require a license amendment pursuant to 10 CFR 50.90. Specifically, the UFSAR change reflected an increased length of time for incore instrumentation room sump instrumentation, as well as gaseous and particulate radiation monitors, to detect a 1 gpm leak. This increased the consequences of an accident or malfunction of equipment important to safety previously evaluated in the safety evaluation report for the reactor coolant system loss of coolant accident (LOCA) leak rate predictions, because the ability to detect a 1 gpm leak within one hour was relied on and credited in the leak-before-break design analysis. The significance of the violation was evaluated under the 10 CFR 50.59 Rule that was in effect at the time of the change, as well as the current 10 CFR 50.59 Rule. The current 10 CFR50.59 Rule requires, in part that "records must include a written evaluation which provides the bases for the determination that the change does not require a license amendment". This information (i.e., the ability to detect a 1gpm leak within one hour) was relied on in part, by NRC for approval of the leak-before-break analysis. Since, the NRC Enforcement Manual states that violations which existed under the old and new rule should be categorized using the current enforcement guidance, this finding was assessed as a SL IV violation. The significance of this violation was not formally evaluated under the Reactor Oversight Process per the Enforcement Policy, because the Agency views 10 CFR 50.59 issues as potentially impeding the regulatory process (i.e., it precluded NRC review of a change to the facility). The finding was not suitable for evaluation using the SDP. Given that the change to the incore instrumentation room sump instrumentation sensitivity capabilities and the gaseous and particulate radiation monitor sensitivities increased the length of time to detect a 1 gpm leak, and the fact that a diverse means of detecting a 1 gpm leak within one hour existed in accordance with Technical Specification (TS) requirements, the delta core damage frequency for the applicable core damage accident sequences stemming from LOCA initiating events were determined to be of very low safety significance. |
| Site: | Catawba  |
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| Report | IR 05000413/2005002 Section 1R15 |
| Date counted | Mar 31, 2005 (2005Q1) |
| Type: | TEV: Severity level IV |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.15 |
| Inspectors (proximate) | A Sabisch E Guthrie L Miller M Ernstes R Cortes |
| INPO aspect | |
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Finding - Catawba - IR 05000413/2005002 | |||||||||
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Finding List (Catawba) @ 2005Q1
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