ML15075A026
| ML15075A026 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 03/09/2015 |
| From: | Clark G Virginia Electric & Power Co (VEPCO) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML15075A026 (7) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 March 9, 2015 U. S. Nuclear Regulatory Commission Serial No.: 14-595A Attention: Document Control Desk NLOS/CDS: RO Washington, DC 20555-0001 Docket Nos.: 50-338/339 License Nos.: NPF-4/7 VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2 CLARIFYING INFORMATION RELATED TO RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION PROPOSED LICENSE AMENDMENT REQUEST PERMANENT FIFTEEN-YEAR TYPE A TEST INTERVAL In a letter dated June 30, 2014 (Serial No.14-272), Virginia Electric and Power Company (Dominion) requested license amendments in the form of changes to the Technical Specifications, for facility Operating License Numbers NPF-4 and NPF-7 for North Anna Power Station Units 1 and 2, respectively. The proposed amendments revise North Anna Power Station Units 1 and 2 Technical Specification (TS) 5.5.15, "Containment Leakage Rate Testing Program," 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 North Anna performance-based leakage testing program in accordance with Option B of 10 CFR 50, Appendix J.
On November 28, 2014, the NRC requested additional information associated with the proposed license amendment request. On January 28, 2015, Dominion provided a response to the NRC request for additional information. Subsequently, during a telephone conversation between the NRC staff and Dominion personnel on March 3, 2015, the NRC staff asked some clarifying questions related to the RAI's. Dominion personnel responded to the questions verbally and the NRC staff was satisfied with the responses. A summary of the questions and the associated Dominion responses is attached to this letter.
The next Unit 1 ILRT is currently due no later than October 2017. Based on the current outage schedule for Unit 1, the current ten-year frequency would require the next Unit 1 ILRT to be performed during the fall 2016 refueling outage. Due to lead time required to procure the services and equipment to perform a Type A test, Dominion requests approval of the proposed change by December 31, 2015.
A0i1-
Serial No. 14-595A Docket Nos. 50-338/339 Page 2 of 3 Should you have any questions or require additional information, please contact Mr. Jay Leberstien at (540) 894-2574.
Respectfully, Gianna C. Clark Vice President - Nuclear Support Services Commitment contained in this letter: None
Attachment:
- 1. Clarifying Information Related to Response to Request for Additional Information COMMONWEALTH OF VIRGINIA COUNTY OF HENRICO The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Gianna C. Clark, who is Vice President - Nuclear Support Services, of Virginia Electric and Power Company. She has affirmed before me that she 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 her knowledge and belief.
Acknowledged before me this . day of lM~e,. 2015.
My Commission Expires: &" -' "
Notary Public S
I WANDA D.Public 4Notary CRAFT Commonwealth of Virginia Reg. # 7520495 l My Commission Expires January 31, 20i(-
Serial No. 14-595A Docket Nos. 50-338/339 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 Mr. J. E. Reasor, Jr.
Old Dominion Electric Cooperative Innsbrook Corporate Center 4201 Dominion Blvd.
Suite 300 Glen Allen, Virginia 23060 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 North Anna Power Station
Serial No. 14-595A Docket Nos. 50-338/339 Attachment I Clarifying Information Related to Response to Request for Additional Information Virginia Electric and Power Company (Dominion)
North Anna Station Units 1 and 2
Serial No. 14-595A Docket Nos. 50-338/339 Page 1 of 3 CLARIFYING INFORMATION RELATED TO RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION TECHNICAL SPECIFICATION CHANGE PROPOSING PERMANENT FIFTEEN-YEAR TYPE A TEST INTERVAL
Background
By letter dated June 30, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML14183B318), Virginia Electric and Power Company (Dominion) requested an amendment to Operating License Numbers NPF-4 and NPF-7 in the form of changes to the Technical Specifications (TSs) for North Anna Power Station Units 1 and 2, respectively. The license amendment request (LAR) proposes a change to TS 5.5.15, "Containment Leakage Rate Testing Program," 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 North Anna performance-based leakage testing program in accordance with Option B of 10 CFR 50, Appendix J. On January 28, 2015, Dominion provided a response to an NRC staff request for additional information related to the amendment request. Subsequently, during a telephone conversation between the NRC staff and Dominion personnel on March 3, 2015, the NRC staff asked some clarifying questions related to the RAI's. Dominion personnel responded to the questions verbally and the NRC staff was satisfied with the responses. A summary of the questions and the associated Dominion responses is provided below.
Summary of NRC Questions Table B. 1 of Attachment 5 to the LAR provides the list of findings from the 2013 peer review and provides an assessment of the impact on the ILRT extension application. In response to the request for additional information PRA RAI-I.a (ADAMS Accession No. ML15034A353) the licensee provided a list of F&Os and the associatedSR, which did not meet Capability Category / requirements of the ASME/ANS RA-Sa-2009 PRA standardendorsedby RG 1.200, Revision 2.
- a. The licensee's disposition for F&Os IE-A6-01, DA-B2-01, DA-C14-01 and QU-B5-01 included in the response to PRA RAI-1.a states that the impact of each of these findings is "expected to be bounded by an order of magnitude increase" and that
"[tihe sensitivity study in Enclosure I of the LAR demonstrates that an order of magnitude increase in CDF or LERF does not impact acceptabilityof the results for this application." Justify how the cumulative effect of all of these open findings not meeting CapabilityCategory I is acceptable for the ILRT extension application.
Serial No. 14-595A Docket Nos. 50-338/339 Page 2 of 3
Response
The sensitivity study in Enclosure 1 of the proposed LAR demonstrated that an order of magnitude increase in core damage frequency (CDF) would not invalidate the results of the ILRT extension application. Although this sensitivity was referenced for individual Facts and Observations (F&Os), the sensitivity study is also considered bounding for the cumulative impact of the open findings. The F&Os which credited the bounding sensitivity study have been further evaluated using sensitivity studies, and their risk impact has been shown to be acceptable. The CDF and Large Early Release Frequency (LERF) increase for IE-A6-01 are 2E-8/yr and IE-9/yr, respectively; for DA-B2-01 are 3E-9/yr and 3E-9/yr, respectively; for DA-C14-01 are 4E-8/yr and 1E-9/yr, respectively; and for QU-B5-01 are 1E-8/yr with no change in LERF. The bounding sensitivity in Enclosure 1 of the LAR considered the risk impact of an order of magnitude increase in CDF, or a CDF increase of 1.55E-5/yr.
Although each of these F&Os was evaluated individually, their cumulative impact is not expected to exceed the increase in risk evaluated by the bounding sensitivity study. As a result, the cumulative effect of the open F&Os on the ILRT extension application is acceptable.
- b. F&Os SY-A 14-01, HR-G2-01, IFQU-A9-01, and IFSO-A4-01 were listed in Table B. I of Attachment 5 to the LAR but not in the response to PRA RAI-I.a. Requirements for Capability Categories I and II are the same for SRs related to those findings. If related SRs meet the requirements for Capability Category I (and II) of ASME/ANS RA-Sa-2009 PRA standard endorsed by RG 1.200, Revision 2, justify how those findings were resolved, as they were initially identified in Table B. I of Attachment 5 to the LAR, or otherwise, justify how the cumulative effect of all of the F&Os (identified in parts a and b of this RAI) 'not meeting Capability Category I is acceptable for the ILRT extension application.
Response
F&Os SY-A14-01, HR-G2-01, IFQU-A9-01, and IFSO-A4-01 were listed in Table B.1 of Attachment 5 to the LAR because all of the F&Os from the peer review report were included in the LAR. The related Supporting Requirements (SRs) for these four F&Os were considered met in the peer review report. Consequently, they were not included in the response to PRA RAI-1.a, which requested only the SRs that did not meet Capability Category I requirements.
Serial No. 14-595A Docket Nos. 50-338/339 Page 3 of 3 References
- 1. Letter from Dominion to U.S. Nuclear Regulatory Commission, "Virginia Electric Power Company, North Anna Power Station Units 1 and 2 Proposed License Amendment Request, Permanent Fifteen-Year Type A Test Interval," dated June 30, 2014.
- 2. Letter from Dominion to U.S. Nuclear Regulatory Commission, "Virginia Electric Power Company, North Anna Power Station Units 1 and 2, Response to Request for Additional Information Proposed License Amendment Request, Permanent Fifteen-Year Type A Test Interval," dated January 28, 2015.