LR-N14-0047, Response to Request for Additional Information (RA133 - RAI36)- Relief Request SC-14R-133, Alternative Repair for Service Water System Piping

Response to Request for Additional Information (RA133 - RAI36)- Relief Request SC-14R-133, Alternative Repair for Service Water System Piping

ML14058A228
Person / Time
Site:	Salem
Issue date:	02/27/2014
From:	Duke P Public Service Enterprise Group
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LR-N14-0047
Download: ML14058A228 (5)

Text

PSEG Nuclear LLC P,O, Box 236, Hancocks Bridge, NJ 08038-0236 NudeayLLC FEB 27 2014 10 CFR 50.55a LR-N 14-0047 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Salem Generating Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-70 and DPR-75 NRC Docket Nos. 50-272 and 50-311

Subject:

Response to Request for Additional Information (RA133 - RAI36)-

Relief Request SC-14R-133, Alternative Repair for Service Water System Piping

References:

(1 ) PSEG letter LR-N13-0064, "Request for Relief from ASME Code Defect Removal for Service Water Buried Piping," dated April 3, 2013, ADAMS Accession No. ML13093A382 (2) PSEG letter LR-N13-0171, "Response to Request for Additional Information - Relief Request SC-14R-133, Alternative Repair for Service Water System Piping," dated August 15, 2013, ADAMS Accession No. ML13227A338 (3) PSEG letter LR-N13-0302, "Response to Request for Additional Information (RAI 31 and RAI 32) - Relief Request SC-14R-133, Alternative Repair for Service Water System Piping," dated January 8,2014, ADAMS Accession No. ML14016A123 (4) NRC email to PSEG, "Request For Additional Information: Salem Units 1 and 2 - Relief Request SC-14R-133 Repair of Service Water piping (TAC MF1375 & 1376)," dated February 6,2014 In Reference 1, as supplemented by References 2 and 3, PSEG Nuclear LLC (PSEG) requested NRC approval of proposed relief request SC-14R-133 for Salem Generating Station, Units 1 and 2. The proposed relief will allow PSEG to repair bell and spigot joints in the buried portions of Service Water System piping in lieu of defect removal requirements in ASME Section XI, IWA 4422.1.

In Reference 4, the NRC staff provided PSEG with a Request for Additional Information (RAI). to this submittal provides the responses to the RAI.

There are no commitments contained in this letter.

FEB 272014 10 CFR 50.55a Page 2 LR-N14-0047 If you have any questions or require additional information, please do not hesitate to contact Ms.

Emily Bauer at 856-339-1023.

Sincerely,

~~e,~Y Manager - licensing Attachment 1 - Response to Request for Additional Information, RAI 33 - RAI 36 cc: Mr. W. Dean, Administrator, Region I, NRC Mr. J. Hughey, Project Manager, NRC NRC Senior Resident Inspector, Salem Mr. P. Mulligan, Manager IV, NJBNE Mr. L. Marabella, Corporate Commitment Tracking Coordinator Mr. T. Cachaza, Salem Commitment Tracking Coordinator

LR-N14-0047 Attachment 1 Response to Request for Additional Information, RAI 33

• RAI 36

LR-N 14-0047 RA133:

What is the length of the harness bolts at the bell-spigot joint of the buried service water piping as shown in Figure 3, page 6, of Attachment 1 to the April 3, 2013 submittal?

PSEG Response to RAI 33:

The harness assembly consists of a clevis on each end and multiple harness bolts connected with couplings, spanning a maximum piping run of approximately 48 feet. Many piping runs are less than 48 feet.

RA134:

l:'Vhat is the length of the harness bolts that will/can be inspected?

PSEG Response to RAI 34:

If a degraded bell and spigot joint is found and the corresponding harness assembly requires inspection, an area including and immediately surrounding the joint will be excavated. The harness assembly will then be inspected, including the portion of the harness bolt in the vicinity of the degraded joint, and the harness bolt coupling. If the entire harness bolt is not uncovered during the initial excavation, PSEG intends to utilize guided wave technology to check for signs of corrosion on the section of the harness bolt that remains buried.

The following Salem event provides quantification of the potential corrosion rates that could be experienced by the harness bolts. In 2010, Salem completed buried pipe inspections for the buried 4 inch, carbon steel Auxiliary Feedwater (AFW) piping that supplies the #12 and #14 steam generators. The AFW piping was found without its protective external coating, and UT measurements were taken. The worst case wall thickness reading was a localized area of 0.077 inches remaining wall out of a nominal pipe thickness of 0.337 inches. This represents a wall loss of 0.26 inches after being buried for approximately 36 years.

As discussed in the response to RAI 26 in the Reference 2 letter, the minimum diameter required of the harness bolt to perform its design requirement is 1.07 inches out of a nominal diameter of 2 inches. Based on previous inspections, it is expected that all harness bolts are indeed coated. However, this operating experience shows that even if a harness bolt was not coated and was corroding, it would be unlikely to experience corrosion at a rate that would approach its minimum required diameter.

As detailed in the response to RAI 25 in Reference 2, previous inspections of the harness bolts identified no signs of corrosion. The use of the guided wave technology, the AFW piping operating experience, and the history of harness bolt inspections at Salem provide reasonable assurance that the targeted inspections proposed by PSEG ensure that the harness assembly will perform its design function.

Any additional scope of the harness bolt inspection will be determined based on the condition of the harness assembly upon initial inspection.

RA135:

What is the harness bolt made of?

PSEG Response to RAI 35:

The harness bolts are constructed of coated SAE Grade 5 carbon steel.

2

LR-N 14-0047 RA136:

Discuss whether the inspections of bell thickness is only from the inside surface and only at the gap between pipes.

PSEG Response to RAI 36:

The bell thickness will be inspected from inside the pipe, at the gap between the concrete core.

This is the only area of the bell surface that is exposed to service water.

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