05000237/FIN-2013007-05
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Finding | |
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| Title | Failure to Provide Complete and Accurate Information on the Isolation Condenser when ITS was Submitted |
| Description | The inspectors identified an Unresolved Item (URI) associated with the information provided to the NRC in a license amendment application. Specifically, in a letter dated March 3, 2000, the licensee inaccurately stated the TS limits established for the IC provided sufficient capability for 20 minutes of operation without makeup water, before beginning to uncover the tube bundles. However, based on the licensee s 1996 design calculation, the IC tube bundles would become significantly uncovered. As part of the review for the NCV documented in Section 1R21.3.b.(4) of this report, the inspectors noted the licensee had provided the NRC inaccurate information in a previous correspondence. In a letter dated March 3, 2000, the licensee requested the NRC to approve a license amendment to upgrade to Improved TS. The proposed change included adding explicit values for the IC minimum starting shell side water level and maximum starting water temperature. The previous version of the TS had no explicit values listed, so the limits were controlled by the licensee administratively. As a result, the proposed change was intended to be more restrictive on plant operation. The inaccurate information was included as part of the above mentioned letter under Enclosure A, Dresden ITS [Improved Technical Specification] Conversion Document, Volume 5. Specifically, the basis for TS SR 3.5.3.1 stated, in part: Based on a scram from 2552.3 MWt (101% RTP), a minimum water level of 6 feet at a temperature of A 210aF in the condenser provides sufficient decay heat removal capability for 20 minutes of operation without makeup water, before beginning to uncover the tube bundles [emphasis added]. The volume and temperature allow sufficient time for the operator to provide makeup to the condenser. On March 26, 1996, the licensee developed calculation BSA-D-95-07, Dresden Isolation Condenser Performance, in order to determine whether the IC would meet its safety function. The calculation determined the water in the shell side would boil down below the top of the tube bundles before makeup was established based on the proposed TS. Specifically, the licensee determined the liquid water level could reach as low as 26.3 percent tube bundle height and result in 75 percent of the tube bundles being uncovered. Therefore, in 1996 the licensee determined the tube bundles would actually become uncovered, before make-up could be established. This was contrary to both statements in the UFSAR and TS Bases that stated the tubes would remain covered for the first 20 minutes. As part of process for implementing BSA-D-95-07 as a design calculation, the licensee should have updated the UFSAR and TS Bases statements be in agreement with the new calculation results. However, the licensee did not update the documents as required. This discrepancy was identified during a subsequent NRC inspection on December 18, 2003. The licensee documented the discrepancy under AR 00191696, Uncovering of the Isolation Condenser Tubes. As part of the corrective actions, the licensee initiated change request 04001 and 04003 to correct the TS Bases and UFSAR respectively. Although the discrepancy was identified, it was not recognized that the inaccurate information was previously submitted to the NRC as part of the Improved TS process. Based on the licensee s 1996 design calculation, a portion of the tube bundles would be exposed before the makeup could be established at the IC proposed limits contrary to information provided to the NRC in the March 3, 2000, submittal. The NRC was unaware of this discrepancy and approved the requested amendment by letter dated March 30, 2001. Based on the new information, it was unclear as to whether the NRC would have approved the IC values included in TS. As stated in Section 1R21.3.b.(4), the licensee implemented administrative limits on the IC level and water temperature; therefore, this unresolved item does not involve an immediate safety concern. This issue is considered Unresolved Item (URI) pending additional information regarding the adequacy of the existing TS values for the IC. (URI 5000237/2013007-05; 05000249/2013007-05, Inaccurate Information Provided During Improved TS Submittal) |
| Site: | Dresden  |
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| Report | IR 05000237/2013007 Section 1R21 |
| Date counted | Jun 30, 2013 (2013Q2) |
| Type: | URI: |
| cornerstone | No Cornerstone |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.21 |
| Inspectors (proximate) | G Roach J Cameron J Corujo-Sandin J Rutkowski J Wojewoda R Elliott T Gob Sherbina Stone J Corujo-Sandin G Morris A Dunlop M Munir B Palagi |
| INPO aspect | |
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Finding - Dresden - IR 05000237/2013007 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Dresden) @ 2013Q2
Self-Identified List (Dresden)
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