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| Site | Quarter | Title | Description | |
|---|---|---|---|---|
| 05000390/FIN-2015004-04 | Watts Bar | 2015Q4 | Shield Building Operability Requirements | The inspectors identified an unresolved item (URI) associated with the requirements of Watts Bar Unit 1 technical specification (TS) 3.6.15, Shield Building. Additional inspection is required to determine if the requirements of 3.6.15.B applied during a specific testing alignment. On September 10, 2015, the licensee conducted 0-SI-65-6-A, Emergency Gas Treatment System (EGTS) Train A 10-Hour Operation. During the 10-hour time period of the test when the EGTS was in service, the auxiliary gas building treatment system was also in service for a Unit 2 construction test. This unique ventilation combination is not normally experienced during the 0-SI-65-6-A surveillance. As a result, shield building annulus differential pressure fell below the limit established by TS surveillance requirement (TSSR) 3.6.15.1 limits for the entire duration of the 10-hr EGTS surveillance. TS limiting condition for operation (LCO) 3.6.15.B requires annulus pressure be restored when it is outside of limits with a required completion time of 8-hrs. The licensee considered the note associated with TS LCO 3.6.15.B, which states that the annulus pressure requirement is not applicable during ventilating operations, required annulus entries, or auxiliary building isolations not exceeding one hour in duration. The licensee considered the alignment they were in at the time to be ventilating operations and thus the requirements of TS LCO 3.6.15.B did not apply. The licensee further considered that the note, as written, allowed grace from the annulus pressure requirement for ventilating operations for an unlimited amount of time. The inspectors were concerned about a possible allowance in the TS to have grace from annulus pressure requirements for longer than the allowed LCO required action completion time. Furthermore, a basis for the note and what can be considered ventilating operations was not immediately apparent. Because more information is necessary to evaluate the proper applicability of TS LCO 3.6.15.B and the associated note, future inspection is required to determine if a more than minor performance deficiency or violation exists associated with this issue. Specifically, the inspectors need to determine if a TS compliance issue exists. This is identified as URI 0500390/2015004-04, Shield Building Operability Requirements. |
| 05000390/FIN-2009002-02 | Watts Bar | 2009Q1 | Acceptability of Plant Alterations Without NRC Submittal | A URI was identified following NRC review of a licensee decision not to provide a submittal in association with temporary alteration TACF 1-07-0002-065, implemented in March 2007 on the Emergency Gas Treatment System (EGTS). The temporary alteration (TACF 1-07-0002-065) changed the system start logic such that both trains would operate in automatic upon receiving the start signal. In their review of the licensees 10CFR50.59 evaluation, the inspectors found that the licensee had made a determination that no license amendment was required, though the supporting paragraph indicated a license amendment was appropriate and was to be accomplished in association with the licensees corrective action program (CAP). Upon further review, the inspectors determined that, as part of a 2005 functional evaluation, a single-failure vulnerability was determined to exist. That same evaluation also recognized that the dose consequence for the system, described in the UFSAR, was based on single fan operation. Given the calculation of record assumptions that all fan flow would be exhausted and the fact that both system fans could achieve flow via that path, the licensee determined that there was an increased beta dose consequence over that described in the UFSAR to Main Control Room operators. NUREG 0800, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants, limits beta dose in the control room to 30 rem. Nuclear Energy Institute (NEI) 96-07, Guidelines for 10 CFR 50.59, Section 4.3.3, states that the criterion for a more than minimal increase in consequence is greater than 10% of the margin to the limit. For this specific case, based on the UFSAR beta dose value of 6.803 rem, an increase of greater than 2.320 rem ((30 rem - 6.803 rem)*0.1) would indicate a more than minimal increase in the consequence. Using the licensee\'s re-evaluated beta dose value of 9.757 rem, the consequence difference was determined to be a 2.954 rem increase in beta dose for main control room operators, which exceeds the NEI 96-07 criterion for a more than minimal increase. The licensee\'s determination of the need for a license amendment was carried as an action item in PER 91670. Between 2005 and 2007 the licensee installed two temporary modifications to address the single-point failure vulnerability. The resulting configuration, at the time of inspection, did not resolve, nor compensate for the flow conditions which resulted in the licensees determination of the need for a submittal as of 2005. During the 2009 inspection, the inspectors found that no licensee amendment request had been submitted to the NRC to support changing the UFSAR while the calculations of record continued to indicate that one was warranted. This issue was unresolved pending additional NRC review to assess the adequacy of the licensees actions in response to the functional evaluation and the adequacy of 10 CFR 50.59 evaluations associated with the related temporary EGTS configuration modifications. This item is identified as URI 05000390/2009002-02: Acceptability of Plant Alterations Without NRC Submittal |