ML14079A082
| ML14079A082 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 03/13/2014 |
| From: | Mark D. Sartain Virginia Electric & Power Co (VEPCO) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 13-435B | |
| Download: ML14079A082 (8) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 March 13, 2014 10 CFR 50.90 U. S. Nuclear Regulatory Commission Serial No.: 13-435B Attention: Document Control Desk NL&OS/GDM: R2 Washington, DC 20555-0001 Docket Nos.: 50-280/281 License Nos.: DPR-32/37 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 RESPONSE TO NRC REQUEST FOR CLARIFICATION PROPOSED LICENSE AMENDMENT REQUEST PERMANENT FIFTEEN-YEAR TYPE A TEST INTERVAL By letter dated August 12, 2013 (Serial No.13-435), Virginia Electric and Power Company (Dominion) requested license amendments in the form of changes to the Technical Specifications, for facility Operating License Numbers DPR-32 and DPR-37 for Surry Power Station (Surry) Units 1 and 2, respectively. The proposed amendments revise the Surry Units 1 and 2 Technical Specification (TS) 4.4.B, "Containment Leakage Rate Testing Requirements," by replacing the reference to Regulatory Guide (RG) 1.163 with a reference to Nuclear Energy Institute (NEI) topical report NEI 94-01, Revision 3-A, as the implementation document used to develop the Surry performance-based leakage testing program in accordance with Option B of 10 CFR 50, Appendix J. Revision 3-A of NEI 94-01 describes an approach for implementing the optional performance-based requirements of Option B, including provisions for extending the Type A primary containment integrated leak rate test (ILRT) intervals to fifteen years and the Type C local leak rate test intervals to 75 months, and incorporates the regulatory positions stated in RG 1.163.
On December 12, 2013, the NRC requested additional information regarding the proposed license amendment request (LAR). Dominion responded to the NRC request for additional Information (RAI) by letter dated January 24, 2014 (Serial No. 13-435A). The Surry NRC Project Manager subsequently contacted Dominion on February 20, 2014 and noted the NRC technical review staff had identified three discrepancies between the information provided in the initial LAR submittal and the RAI response. Two of the discrepancies concerned differing values for Type B and C leakage values, while the third discrepancy concerned the number of ASME Section XI Code repairs performed on the Unit 1 and Unit 2 Containment structures.
In resolving the discrepancies in the Type B and C as-found and as-left leakage values provided in the August 12, 2013 and January 24, 2014 submittals, a validation of the penetration leakage data obtained from the specific refueling outage test reports was performed using the peer review process. An independent review of the leakage data was also performed subsequent to the validation effort. As a result of these actions, additional discrepancies were identified. The validated and independently reviewed Type B and C as-found and as-left leakage values by outage date are provided in the attachment and supersede the previously provided leakage values in the August 12, 2013 and January 24, 2014 submittals. The conclusion that neither unit's overall Type B and C leakage has approached the 0.6 La leakage limit remains unchanged. The attachment also provides a correction to the August 12, 2013 letter regarding the number of penetrations
Serial No. 13-435B Docket Nos. 50-280/281 Page 2 of 3 currently being tested at an increased frequency due to leakage performance. To address the occurrence of these identified discrepancies in our previous submittals, a corrective action assignment was entered into the station Corrective Action Program to review the process used to compile Appendix J Program data and determine actions to ensure the maintenance of accurate information.
Regarding the Units 1 and 2 Containment ASME Section Xl Code repairs, the information provided in the January 24, 2014 RAI response letter (i.e., three Unit 1 and two Unit 2 Code repairs) is accurate and supersedes the numbers of Code repairs reported in the August 12, 2013 submittal.
As noted above, the Type B and C leakage values and the number of penetrations being tested at an increased frequency have been independently reviewed and validated for accuracy and included in this letter in the attachment. Separately, the Containment Code repair information in the previous RAI response was confirmed to be accurate. The revised information does not affect the conclusion of the significant hazards consideration discussed in the August 12, 2013 letter (Serial No.13-435).
Should you have any questions or require additional information, please contact Mr. Gary Miller at (804) 273-2771.
Sincerely, Mark D. Sartain Vice President - Nuclear Engineering Attachment - Validated Type B and C Penetration Test Results Since the Unit 1 2006 Type A Test and the Unit 2 2000 Type A Test and Corrected Number of Penetrations Being Tested at Increased Frequency due to Leakage Performance Commitments contained in this letter: An assignment has been made in the Corrective Action Program to review the process used to compile Appendix J Program data and determine required actions to ensure information accuracy.
COMMONWEALTH OF VIRGINIA COUNTY OF HENRICO The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Mr. Mark D. Sartain, who is Vice President - Nuclear Engineering of Virginia Electric and Power Company. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that company, and that the statements in the document are true to the best of his knowledge and belief.
Acknowledged before me this 13 day of Mayc-&. ,2014.
My Commission Expires: TEecgiýer- 31) .
ICRAIG 0SLY Notary Public __
Commonwealth of Virginia N P Reg. # 7518653 My Commission Expires December 31, 20A61
Serial No. 13-435B Docket Nos. 50-280/281 Page 3 of 3 cc: U.S. Nuclear Regulatory Commission - Region II Marquis One Tower 245 Peachtree Center Avenue, NE Suite 1200 Atlanta, GA 30303-1257 State Health Commissioner Virginia Department of Health James Madison Building - 7 th floor 109 Governor Street Suite 730 Richmond, VA 23219 Ms. M. C. Barillas NRC Project Manager Surry U.S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9A 11555 Rockville Pike Rockville, MD 20852-2738 Dr. V. Sreenivas NRC Project Manager North Anna U.S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9A 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Surry Power Station
Serial No. 13-435B Docket Nos. 50-280/281 Attachment Validated Type B and C Penetration Test Results Since the Unit 1 2006 Type A Test and the Unit 2 2000 Tvpe A Test and Corrected Number of Penetrations Being Tested at Increased Frequency due to Leakage Performance Virginia Electric and Power Company (Dominion)
Surry Power Station Units I and 2
Serial No. 13-435B Docket Nos. 50-280/281 Attachment Page 1 of 4 Validated Type B and C Penetration Test Results Since the Unit 1 2006 Type A Test and the Unit 2 2000 Type A Test Validated Type B and C Penetration Test Results since Unit 1 2006 Type A Test Type B&C Type B&C As-found /
As-found As-left As-left Valves Requiring Corrective Date Leakage Leakage Percent Increased Test Actions Min-Path Max-Path (AFIAL / Frequency 4 Required (scfh)1 (scfh)2 0.6 La x 100)3 05/2006 10.21 16.49 5.9 / 9.5 7 7 10/2007 3.19 18.15 1.9/10.5 5 5 05/2009 3.97 15.73 2.3 / 9.1 4 4 10/2010 6.45 21.99 3.7/ 12.7 5 5 05/2012 10.9 12.76 6.3 /7.4 6 6 10/2013 10.13 18.22 5.9/10.5 4 45
- 1. Per ANSI/ANS 56.8 - 1994 and NEI 94-01, "the combined As-Found leakage rates, determined on a minimum pathway leakage rate basis, for all newly tested penetrations when summed with the As-Left minimum pathway leakage rate for all other penetrations not tested shall be less than 0.6 La when Containment Integrity is required."
- 2. Per ANSI/ANS 56.8 - 1994 and NEI 94-01, "the combined As-Left leakage rates determined on a maximum pathway leakage rate basis for all penetrations shall be less than 0.6 La prior to entering a mode where Containment Integrity is required following an outage or shutdown that included Type B & C testing. These combined leakage rate determinations shall be done with the latest leakage rate test data available, and shall be kept as a running summation of the leakage rates."
- 3. La = 290 scfh and 0.6 La = 174 scfh.
- 4. Type B and C leakage results have not exceeded the 0.6 La acceptance criteria.
Administrative limits for leakage rates in the test procedure are established and documented for each Type B and C component prior to performance of local leakage rate test. The administrative limit assigned to each component is specified such that it is an indicator of potential valve or penetration degradation. In accordance with the Performance Based Containment Leakage Rate Program, exceeding the administrative limit triggers increased testing for each individual valve or penetration until two successful As-Found Type B or C tests are completed. Administrative limits are specific to individual penetrations or valves and are not the surveillance acceptance criteria for Type B and C tests.
- 5. The Surry Periodic Test Procedure for Containment Isolation Valve Local Leak Rate Testing (Type C Containment Testing) specifies that any valve exceeding the maximum leakage acceptance criterion shall be repaired/replaced or evaluated/approved by the Facility Safety Review Committee. During the Unit 1 Fall 2013 refueling outage, four Containment Isolation
Serial No. 13-435B Docket Nos. 50-280/281 Attachment Page 2 of 4 Valves had Local Leakage Rate Test results with a measured leakage greater than the maximum leakage acceptance criteria of the Periodic Test Procedure. The corrective action taken to address these four valves is discussed in the following paragraphs.
- Penetration 70, Valve 01-RS-MOV-156B As-found measured leakage: 5.3 scfh (Administrative limit = 4.5 scfh)
Resolution: Limit switch adjustments were performed and the seating torque was increased to address the leakage. However, these actions did not reduce the leakage to an acceptable value, so the valve seat was also replaced.
Consistent with Note 4 above, valve 01-RS-MOV-156B will require testing each refueling outage until two successful leakage rate tests are recorded.
As-left measured leakage: 0.0 scfh
- Penetration 90, Valves 01-VS-MOV-100C, 100D, 101 As-found measured leakage: 4.1 scfh (Administrative limit = 3.5 scfh)
Resolution: An engineering evaluation was performed and provided the technical basis for accepting the measured Type C leakage for Penetration 90. It was determined that the as-left leakage of the Penetration 90 containment isolation valves 01-VS-MOV-100C, 100D, 101 is acceptable, and repair or replacement of the leaking containment isolation valves may be deferred to the next Unit 1 refueling outage. This deferral is acceptable since the total as-left Type B and C leakage (including the as-left leakage for Penetration
- 90) for the Unit 1 Fall 2013 refueling outage is below the maximum allowable Type B and C leakage value of 174 scfh (0.6 La), and sufficient margin exists to 0.6 La. Consistent with Note 4 above, valves 01-VS-MOV-100C, 100D, 101 will require testing each refueling outage until two successful leakage rate tests are recorded.
As-left measured leakage: 4.1 scfh
Serial No. 13-435B Docket Nos. 50-280/281 Attachment Page 3 of 4 Validated Type B and C Penetration Test Results since Unit 2 2000 Type A Test Type B&C Type B&C As-found / Valves As-found As-left As-left Requiring Corrective Date Leakage Leakage Percent Increased Actions Min-Path Max-Path (AF/AL I Test Required (scfh)1 (scfh) 2 0.6 La x 100)3 Frequency 4 10/2000 4.6 13.23 2.7/7.6 5 5 05/2002 37.38 22.65 21.5/13.1 5 5 10/2003 13.38 10.72 7.7/6.2 4 4 05/2005 4.67 16.29 2.7 / 9.4 5 5 10/2006 7.53 10.55 4.4/6.1 2 2 05/2008 5.15 8.17 3.0/4.7 4 4 10/2009 11.36 15.43 6.6/8.9 3 3 05/2011 7.53 11.7 4.4/6.8 3 3 10/2012 16.15 12.72 9.3 /7.4 2 25
- 1. Per ANSI/ANS 56.8 - 1994 and NEI 94-01, "the combined As-Found leakage rates, determined on a minimum pathway leakage rate basis, for all newly tested penetrations when summed with the As-Left minimum pathway leakage rate for all other penetrations not tested shall be less than 0.6 La when Containment Integrity is required."
- 2. Per ANSI/ANS 56.8 - 1994 and NEI 94-01, "the combined As-Left leakage rates determined on a maximum pathway leakage rate basis for all penetrations shall be less than 0.6 La prior to entering a mode where Containment Integrity is required following an outage or shutdown that included Type B and C testing. These combined leakage rate determinations shall be done with the latest leakage rate test data available, and shall be kept as a running summation of the leakage rates."
- 3. La = 290 scfh and 0.6 La = 174 scfh.
- 4. Type B and C leakage results have not exceeded the 0.6 La acceptance criteria.
Administrative limits for leakage rates in the test procedure are established and documented for each Type B and C component prior to performance of local leakage rate test. The administrative limit assigned to each component is specified such that it is an indicator of potential valve or penetration degradation. In accordance with the Performance Based Containment Leakage Rate Program, exceeding the administrative limit triggers increased testing for each individual valve or penetration until two successful As-Found Type B or C tests are completed. Administrative limits are specific to individual penetrations or valves and are not the surveillance acceptance criteria for Type B and C tests.
- 5. The Surry Periodic Test Procedure for Containment Isolation Valve Local Leak Rate Testing (Type C Containment Testing) specifies that any valve exceeding the maximum leakage acceptance criterion shall be repaired/replaced or evaluated/approved by the Facility Safety Review Committee. During the Unit 2 Fall 2012 refueling outage, two Containment Isolation Valves had Local Leakage Rate Test results with a measured leakage greater than the
Serial No. 13-435B Docket Nos. 50-280/281 Attachment Page 4 of 4 maximum leakage acceptance criteria of the Periodic Test Procedure. The corrective action taken to address these two valves is discussed in the following paragraphs.
- Penetration 56A, Valve 02-SS-TV-206A As-found measured leakage: 10.4 scfh (Administrative limit = 1.0 scfh)
Resolution: To address the leakage, a new gasket, plug, and spring were installed, and the valve seats were lapped. Consistent with Note 4 above, valve 02-SS-TV-206A will require testing each refueling outage until two successful leakage rate tests are recorded.
As-left measured leakage: 0.9 scfh
- Penetration 56A, Valve 02-SS-TV-206B As-found measured leakage: 13.6 scfh (Administrative limit = 1.0 scfh)
Resolution: To address the leakage, a new plug was installed, and the valve seats were lapped. However, these actions did not reduce the leakage to an acceptable level, so an engineering evaluation was performed and provided the technical basis for accepting the measured Type C leakage for valve 02-SS-TV-206B. It was determined that the as-left leakage of valve 02-SS-TV-206B is acceptable, and repair or replacement of the leaking valve may be deferred to the next Unit 2 refueling outage. This deferral is acceptable since the total as-left Type B and C leakage (including the as-left leakage for valve 02-SS-TV-206B) for the Unit 2 Fall 2012 refueling outage is below the maximum allowable Type B and C leakage value of 174 scfh (0.6 La),
and sufficient margin exists to 0.6 La. Consistent with Note 4 above, valve 02-SS-TV-206B will require testing each refueling outage until two successful leakage rate tests are recorded.
As-left measured leakage: 3.0 scfh Corrected Number of Penetrations Being Tested at Increased Frequency due to Leakage Performance On page 10 of 20 in Attachment 1 of the August 12, 2013 letter, it is stated that "Currently there are four (4) penetrations in Unit 2 and eight (8) in Unit 1 that are being tested at an increased frequency due to leakage performance." As a result of the validation effort and independent review, it was found that the number of penetrations being tested at an increased frequency due to leakage performance is one (1) in Unit 2 and two (2) in Unit 1.