ML12306A352

Request for Additional Information Regarding Relief Request 2-ISI-28

ML12306A352
Person / Time
Site:	Browns Ferry
Issue date:	11/02/2012
From:	Ellen Brown Plant Licensing Branch II
To:	James Shea Tennessee Valley Authority
Brown, Eva A.
References
TAC ME8779
Download: ML12306A352 (3)

Text

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Mr. Joseph W. Shea Vice President, Nuclear Licensing Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402*2801

SUBJECT:

BROWNS FERRY NUCLEAR PLANT, UNIT 2

• REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST 2*ISI*28 (TAC NO. ME8779)

Dear Mr. Shea:

By letter dated May 24,2012, Tennessee Valley Authority (TVA) submitted a request for relief from weld examination coverage requirements specified in the American Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI. Specifically, this request for relief addresses a standby liquid control nozzle-to-vessel weld. Ultrasonic examinations were performed on the accessible areas of these welds to the maximum extent practical for the design configuration of the welds.

Based on our review of your submittal, the U. S. Nuclear Regulatory Commission staff finds that a response to the enclosed request for additional information is needed before we can complete the review.

A draft copy of the enclosed information request was e-mailedtoTVAonAugust22.2012.This request was discussed with Mr. Tom Hess of your staff on October 25,2012, wherein it was agreed that a call clarifying the information request was not needed. TVA agreed to respond to the request for information within 90 days of the date of this letter.

Should you have any questions, please feel free to contact me at (301) 415*2315.

Sincerely, IRA!

Eva A. Brown, Senior Project Manager Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-260

Enclosure:

Request for Additional Information cc w/encl: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION RELIEF REQUEST 2-ISI-28 BROWNS FERRY NUCLEAR PLANT UNIT 2 TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-2S0

1. The Table on page E-S, indicates that the request is for two welds. For each sketch provided, identify the weld{s) that relief is being requested by using standard American Welding Society weld symbols pointing to each weld face to identify that weld. If a weld face contains more than one weld designation, identify this on each sketch

2. Identify the American Society of Mechanical Engineers material designation for each part of each weld. If a material is clad with Stainless Steel or other metal, clearly identify that material.

3. Provide specific details of the basis that 100 percent ultrasonic testing cannot be accomplished, such as the specific design and the conditions that prevent the welds from being examined 100 percent by the ultrasonic testing technique.

4. Address whether any indications, detected on the RPV nozzle-to-vessel welds, were evaluated to be either relevant or nonrelevant indications. If any indications were detected, discuss the disposition of these indications.

5. Address how the coverage for the N10-IR inner radius examination was calculated.

Provide a coverage map showing the areas that were missed.

S. From the Coverage Data Sheets (CDSs), CDS-01 shows that the SO-degree probe can approach very close to the edge of the fillet. In CDS-02, the drawing shows that the 50-degree probe stops much earlier and the line labeled "50°" appears to be drawn with an angle of SO degrees. Provide a drawing that shows the regions inspected by the 50- and SO-degree probes.

7. In CDS-02, showing the circumferential examination for axial flaws, the drawing appears to show that the weld was inspected using a 50- and SO-degree skew. This drawing appears to be a drawing of the axial inspection. Please verify the skew angles used to calculate the coverage of the circumferential examination.

8. For Weld N 1O-NV, the calculation for circumferential ultrasonic examination coverage gives a higher weight to the lower 15 percent than the upper 85 percent. From the CDSs, it appears that the Composite Axial plus Circumferential Coverage is 81.7 percent, not 8S.2 percent. Confirm that the Composite Axial plus Circumferential Coverage is 8S.2 percent. If not, address the discrepancy.

Enclosure

'.. ML12306A352

• Via email OFFICE LPL2-21PM LPL2-21LA DE/EVIB/BC LPL2-21BC(A)

NAME EBrown BClayton SRosenberg* JQuichocho DATE 1112/12 1111112 08/21/12 1112112