NRC 2005-0108, Response to Request for Additional Information: Relief Request from the Provisions of ASME Section Xl, IWA-5244, Buried Components, Relief Request 15

Response to Request for Additional Information: Relief Request from the Provisions of ASME Section Xl, IWA-5244, Buried Components, Relief Request 15

ML052500533
Person / Time
Site:	Point Beach
Issue date:	08/26/2005
From:	Koehl D Nuclear Management Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NRC 2005-0108, TAC MC7770, TAC MC7771
Download: ML052500533 (4)

Text

Committed to Nuclear Excellence Point Beach Nuclear Plant Operated by Nuclear Management Company, LLC August 26, 2005 NRC 2005-0108 10 CFR 50.55a U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Point Beach Nuclear Plant, Units 1 and 2 Dockets 50-266 and 50-301 License Nos. DPR-24 and DPR-27 Response to Request for Additional Information:

Relief Request from the Provisions of ASME Section Xl, IWA-5244, "Buried Components," Relief Request 15 (TAC Nos. MC7770 and MC7771)

Reference:

1) Letter from NMC to NRC dated January 21, 2005 (NRC 2002-0015)

2) NRC Request for Additional Information (RAI) dated August 12, 2005 In Reference 1, Nuclear Management Company, LLC (NMC) submitted a request for relief for Point Beach Nuclear Plant (PBNP), Units I and 2, from certain requirements of the 1998 Edition through the 2000 Addenda of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section Xl, IWA-5244, "Buried Components", for the fourth inservice interval in accordance with the provisions of 10 CFR 50.55a(a)(3)(ii).

In Reference 2, the Nuclear Regulatory Commission (NRC) staff requested additional information to complete their review of Reference 1. The enclosure to this letter contains the NMC response to the staffs questions.

This letter contains no new commitments and no revisions to existing commitments.

A/~/

Dennis L. Koehl Site Vice-President, Point Beach Nuclear Plant Nuclear Management Company, LLC Enclosure tq 7 6590 Nuclear Road

• Two Rivers, Wisconsin 54241 Telephone: 920.755.2321

Document Control Desk Page 2 cc: Administrator, Region 111, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC Mike Verhagen, Department of Commerce, State of Wisconsin

ENCLOSURE 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST 15 REQUEST FOR RELIEF FROM THE EXAMINATION REQUIREMENTS OF ASME SECTION Xl, IWA-5244, "BURIED SERVICE WATER PIPING" The following information is provided in response to the Nuclear Regulatory Commission (NRC) staffs request for additional information (RAI) regarding Nuclear Management Company (NMC) letter dated January 21, 2005, which submitted a request for relief for Point Beach Nuclear Plant (PBNP), Units 1 and 2, from certain requirements of the 1998 Edition through the 2000 Addenda of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section Xl, IWA-5244, "Buried Components", for the fourth inservice interval in accordance with the provisions of 10 CFR 50.55a(a)(3)(ii). The NRC staffs questions are restated below with the NMC response following.

NRC Question 1:

The licensee stated that: "A review of previous PBNP pressures tests indicated that prior Inservice Inspection (ISI) intervals had not met Code requirements for performing pressure testing on buried portions of the main SW headers as required by IWA-5244 of the 1986 Edition of ASME Section Xl." Please explain in detail the tests that were performed in place of the required pressure tests and the actions taken as a result of not meeting the requirements of ASME Section Xi for the previous intervals.

NMC Response:

PBNP performed a hydrostatic pressure test on the buried service water piping during the second inservice inspection interval, and a system inservice (pressure) test during the third inservice inspection interval. These tests did not reveal leakage in the system.

The tests specifically ensured that piping and components within the test boundary withstood the test pressure without a loss of structural integrity. Test Procedure IT-07, "Inservice Testing of Service Water Pumps and Valves", ensured flow was unimpaired by verifying the system delivered the required amount of service water through the buried piping to plant components. The successful completion of both tests confirmed the buried piping was intact and capable of performing its function.

During the second and third ISI intervals, while ASME Section Xi Code rules were still evolving, the rules were interpreted to allow testing of buried piping by the methods described above. It was believed that the buried piping could not be practically isolated due to the design of the system, which included butterfly isolation valves. The system was determined to be incapable of isolation for the purpose of a pressure drop test.

Verifying piping integrity, by unimpaired flow, was the method selected. As a result, no relief request was submitted.

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NRC Question 2:

The licensee stated that the piping is not susceptible to Microbiologically Influenced Corrosion (MIC) because of continuous high flow rate of water through the piping.

Please identify the construction materials of the underground piping. State if either lining on the internal diameter or pipe wrapping on the outside diameter has been employed and the material used.

NMC Response:

Material specifications for this piping and its associated coatings are defined in Point Beach Design Guide DG-M03. The underground service water piping is 30-inch diameter, class HB-1 9 carbon steel piping. The piping is either fabricated with A-1 55 KC 60 CL 2 or ASTM A-672 GR B60 Class 20 material. Per design, the exterior surface of the buried pipe has a coat of primer, followed by a hot coat of coal-tar enamel. A single layer of asbestos felt wrap, finished with one coat of water resistant whitewash, or a single wrap of Kraft paper applied in accordance with AWWA C-203-62, is bonded with the coal-tar enamel. There is no requirement to have any coating on the inside of the pipe.

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