ML092440434
ML092440434 | |
Person / Time | |
---|---|
Site: | Kewaunee ![]() |
Issue date: | 08/24/2009 |
From: | Dominion Energy Kewaunee |
To: | Office of Nuclear Reactor Regulation |
References | |
09-491 | |
Download: ML092440434 (14) | |
Text
Serial No.09-491 ATTACHMENT 4 LICENSE AMENDMENT REQUEST 249 KEWAUNEE POWER STATION CONVERSION TO IMPROVED TECHNICAL SPECIFICATIONS APPLICABILITY OF WCAP-14333 AND WCAP 15376 TO KEWAUNEE POWER STATION NON-PROPRIETARY KEWAUNEE POWER STATION DOMINION ENERGY KEWAUNEE, INC.
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 1 of 13 APPLICABILITY OF WCAP-14333 AND WCAP-15376 TO KEWAUNEE The following tables demonstrate the applicability of WCAP-14333 and WCAP-15376 to Kewaunee Power Station (Kewaunee). The tables were taken directly from the Westinghouse Owners Group (WOG) implementation guidance letters and fulfill part of condition 1 from both NRC SERs approving the above WCAPs. Table 1 and 2 show applicability of the general analysis parameters from the WCAPs. Table 3 shows the applicability of the reactor trip actuation signals while Table 4 shows the applicability of the ESFAS actuation signals. Table 5 demonstrates the applicability of the human reliability analysis and fulfills condition 4 of the WCAP-15376 NRC SER.
Table 1 WCAP-14333 Implementation Guidelines:
Applicability of the Analysis General Parameters WCAP-14333 Analysis Plant Specific Parameter Assumptions Parameter Logic Cabinet Type (1) SSPS or Relay Relay Component Test Intervals (2)
- Analog channels 3 months 1 month (12)
- Logic cabinets (SSPS) 2 months NA
- Logic cabinets (Relay) 1 month 1 month
- Master Relays (SSPS) 2 months NA
- Master Relays (Relay) 1 month 1 month
- Slave Relays 3 months 18 months
- Reactor trip breakers 2 months 1 month (13)
Analog Channel Calibrations (3)
- Done at-power Yes Yes
- Interval 18 months 18 months (3)
NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 2 of 13 Table 1 (continued)
WCAP-14333 Implementation Guidelines:
Applicability of the Analysis General Parameters Parameter WCAP-14333 Analysis Plant Specific Assumptions Parameter Typical At-Power Maintenance Intervals (4)
- Analog channels 24 months Equal to or greater than 24 months
- Logic cabinets (SSPS) 18 months NA
- Logic cabinets (Relay) 12 months Equal to or greater than 12 months
- Master relays (SSPS) Infrequent (5) NA
- Master relays (Relay) Infrequent (5) Infrequent
- Slave relays Infrequent (5) Infrequent
- Reactor trip breakers 12 months 18 months AMSAC (6) Credited for AFW pump AMSAC initiates AFW start pump start Total Transient Event Frequency (7) 3.6 1.2 ATWS Contribution to CDF (current PRA model) (8) 8.4E-6 7.2E-7 Total CDF from Internal Events (current PRA model) (9) 5.8E-5 3.2E-5 Total CDF from Internal Events (IPE) (10) Not Applicable 6.6E-5 NOTES FOR TABLE 1:
- 1. Both types of logic cabinets, SSPS and Relay, are included in WCAP-14333. The analysis is applicable to Kewaunee.
- 2. Test intervals are equal to or greater than those used in WCAP-14333 or are justified in notes 12 and 13.
Therefore, the WCAP-14333 analysis is applicable to Kewaunee.
NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 3 of 13 NOTES FOR TABLE 1 (CONTINUED):
- 3. Channel calibrations can be performed at power and most calibration intervals are equal to or greater than that used in WCAP-14333. The exception is the Nuclear Power Range, which is calibrated quarterly at power. The frequency of this calibration will not change with this proposed amendment. This difference in calibration frequency does not effect the conclusions of the WCAP. Therefore, the WCAP analysis is applicable to Kewaunee.
- 4. Kewaunees maintenance intervals are equal to or greater than those used in WCAP-14333, and therefore, the analysis is applicable to Kewaunee.
- 5. Only corrective maintenance is performed on master and slave relays. The maintenance interval on typical relays is relatively long, that is, experience has shown they do not typically fail completely. Failure of slave relays usually involves failure of individual contacts. This is consistent with Kewaunees experience and WCAP-14333 applies to Kewaunee.
- 6. AMSAC will initiate AFW pump start and WCAP-14333 is applicable to Kewaunee.
- 7. This entry includes the total frequency for initiators requiring a reactor trip signal to be generated for event mitigation to assess the importance of ATWS events to CDF. Events initiated by a reactor trip are not included.
Since the plant specific value is less than the WCAP-14333 value, this analysis is applicable to Kewaunee.
- 8. This entry includes the ATWS contribution to core damage frequency (from at-power, internal events). This is required to determine if the ATWS event is a large contributor to CDF.
- 9. This entry indicates the total CDF from internal events (including internal flooding) for the most recent PRA update.
This is required for comparison to the NRCs risk-informed CDF acceptance guidelines.
- 10. This entry indicates the total CDF from internal events from the IPE model submitted to the NRC in response to Generic Letter 88-20, Individual Plant Examination for Severe Accident Vulnerabilities - 10 CFR 50.54(f). See Note 11 for differences between the most recent Kewaunee PRA model update and that included in the Kewaunee GL 88-20 response.
NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 4 of 13 NOTES FOR TABLE 1 (CONTINUED):
- 11. The Kewaunee PRA has been frequently updated since the final IPE submittal in December 1992, and incorporates plant design changes and upgraded methods to be consistent with the current state of the art. This list is not an exhaustive list, but a list of the major changes.
- Removed operator action to stop RHR pumps running on miniflow
- Took credit for RWST refill
- Took credit for air accumulators on certain AOV's
- Modeled alternate means of cooling air compressors
- Changed reactor cavity configuration from dry to wet
- Test and maintenance modeled for both trains instead of just one
- Loss of DC bus modeled for each train instead of most conservative
- Loss of AC Bus modeled for each train instead of most conservative
- Component cooling modeled so each train has a 0.5 probability of being in standby
- Charging pump relief valve model corrected
- Service water strainers removed based on analysis
- Pressurizer PORV block valves no longer assumed open
- Converted from Grafter to WinNUPRA
- Updated all failure rate data, including initiating events
- Recalculate all important HEPs
- Redesigned steam line break, modeling PTS concerns
- Resolved numerous Peer review Facts & Observations
- Reperformed all thermal hydraulic computer code calculations incorporating new steam generators and power uprate. Addressed Category A and B Facts and Observations from the Westinghouse Owners Group peer review.
- Added new flooding model to address inadequacies in the IPE model.
NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 5 of 13 NOTES FOR TABLE 1 (CONTINUED):
- 12. Analog channel test is at the original licensed interval of one month. The STI increase to three months was justified and approved by the NRC in WCAP-10271-P-A, which has not been implemented at Kewaunee.
However, this analysis remains applicable.
- 13. RTB testing is at the original licensed interval of one month. This interval was not evaluated in the WCAP.
Therefore, the WCAP RTB STI is not applicable and Kewaunee will not implement any change to RTB test frequency.
NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 6 of 13 Table 2 WCAP-15376 Implementation Guidelines:
Applicability of the Analysis General Parameters a,c NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 7 of 13 Table 2 WCAP-15376 Implementation Guidelines:
Applicability of the Analysis General Parameters a,c NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 8 of 13 NOTES FOR TABLE 2 (CONTINUED): a,c NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 9 of 13 Table 3 WCAP-14333 and WCAP-15376 Implementation Guidelines:
Applicability of Analysis Reactor Trip Actuation Signals a,c NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 10 of 13 NOTES FOR TABLE 3: a,c NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 11 of 13 Table 4 WCAP-14333 and WCAP-15376 Implementation Guidelines:
Applicability of Analysis Engineered Safety Features Actuation Signals a,c NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 12 of 13 NOTES FOR TABLE 4: a,c NON-PROPRIETARY
NON-PROPRIETARY Serial No.09-491 Docket No. 50-305 Attachment 4 Page 13 of 13 APPLICABILITY OF WCAP-14333 AND WCAP-15376 TO KEWAUNEE Table 5 WCAP-15376 Implementation Guidelines:
Applicability of the Human Reliability Analysis NON-PROPRIETARY