ML111090262

Response to Request for Additional Information Relief Request RR-04-05 Alternate Pressure/Flow Testing for Service Water Buried Piping

ML111090262
Person / Time
Site:	Millstone
Issue date:	04/18/2011
From:	Price J Dominion, Dominion Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
11-166, TAC ME4472
Download: ML111090262 (5)

Text

Dominion Nuclear Connecticut, Inc.

5000 Dominion Boulevard, Glen Allen, Virginia 23060 Web Address: www.dom.com April 18, 2011 U. S. Nuclear Regulatory Commission Serial No.11-166 Attention: Document Control Desk NSSLl\NDC RO Washington, DC 20555 Docket No. 50-336 License No. DPR-65 DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2 REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST RR-04-05 ALTERNATE PRESSURE/FLOW TESTING FOR SERVICE WATER BURIED PIPING, (T AC NO. ME4472)

Dominion Nuclear Connecticut, Inc. (DNC) submitted the Millstone Power Station Unit 2 (MPS2) fourth 10-year lSI program and associated proposed alternatives and relief requests in a letter dated July 29, 2010 and supplemental letter dated August 5, 2010. ONC requested the use of alternatives to certain American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI requirements. Included in the submittal was Relief Request RR 05, which requests the use of alternative pressure testing requirements for service water system buried piping segments. In a letter dated March 16, 2011, the NRC transmitted a request for additional information (RAI) related to RR 05. ONC agreed to respond to the RAI by April 27, 2011.

Attachment 1 provides ONC's response to the NRC RAI.

If you have any questions regarding this submittal, please contact Wanda Craft at (804) 273-4687.

Sincerely,

Serial No.11-166 Docket No. 50-336 RAI Response for RR-04-05 Page 2 of 2

Attachment:

1. Response to Request for Additional Information Regarding Relief Request RR-04-05 Alternate Pressure/Flow Testing for Service Water Buried Piping Commitments made in this letter:

1. None cc: U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-1415 J. 0 Hughey Project Manager - Millstone Power Station U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 08-B1A Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station

Serial No.11-166 Docket No. 50-336 ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST RR-04-05, "ALTERNATE PRESSURE/FLOW TESTING FOR SERVICE WATER BURIED PIPING" DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

Serial No.11-166 Docket No. 50-336 RAI Response for RR-04-05 Attachment 1, Page 1 of 2 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST RR-04-05. "ALTERNATE PRESSUREIFLOW TESTING FOR SERVICE WATER BURIED PIPING" Dominion Nuclear Connecticut, Inc. (DNC) submitted the Millstone Power Station Unit 2 (MPS2) fourth 10-year lSI program and associated proposed alternatives and relief requests in a letter dated July 29, 2010 and supplemental letter dated August 5, 2010.

ONC requested the use of alternatives to certain American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI requirements.

Included in the submittal was Relief Request RR-04-05, which requests the use of alternative pressure testing requirements for service water system buried piping segments. In a letter dated March 16, 2011, the NRC transmitted a request for additional information (RAI) related to RR-04-05. This attachment provides DNC's response to the NRC RAI.

Question 1 The Piping and Instrument Diagram (P&ID) that is included with the relief request shows buried piping and four flow elements in grid coordinate C-13.

a) Is the buried piping indicated in grid coordinate C-13 the only piping being covered in this relief request, or is the 24"-KE-1 piping (flagged on the P&ID) in tunnels also being covered?

b) Are the flow elements downstream of the buried piping in grid coordinate C-13 the flow elements used for pump inservice testing (1ST) surveillance?

c) Are there piping segments, covered by this relief request, that are downstream of the flow elements used for pump 1ST surveillance and, if so, what means will be used to detect pipe leakage in these segments?

DNC Response a) The buried piping in grid C-13 is the only piping covered in this request. The 24"-

KE-1 piping in the pipe tunnel is accessible and receives a visual VT-2 examination in accordance with the requirements of the ASME Section XI Code.

The line number 24"-KE-1 that is flagged on the P&IO (two places) was only meant to highlight the line number, not to indicate relief request coverage for that portion of piping.

b) Yes, the flow elements downstream of the buried piping in grid coordinate C-13 are the flow elements used for pump 1ST surveillance.

c) The piping downstream of the flow elements used for pump 1ST surveillance is not covered by this relief request. The piping downstream of the flow elements

Serial No.11-166 Docket No. 50-336 RAI Response for RR-04-05 Attachment 1, Page 2 of 2 receives a visual (VT-2) examination in accordance with the requirements of the ASME Section XI Code.

Question 2 What is the total length of 24"-KE-1 piping considered in this relief request?

ONC Response The total length of 24"-KE-1 piping subject to this relief request is approximately 494 feet.

Question 3 Provide a brief summary of the 24"-KE-1 lining inspection results and pipe leak history.

ONC Response Internal visual inspections of the lining of the buried piping segments of 24"-KE-1 has identified no significant degradation of the liner. There is no history of leakage for the buried piping segments of line 24"-KE-1.