ML13360A210

Revision of Commitment for Inspection and Repair of Kapton Insulated Pigtails within Electrical Containment Penetrations

ML13360A210
Person / Time
Site:	Watts Bar
Issue date:	12/17/2013
From:	Hruby R Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML13360A210 (3)

Text

Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381-2000 December 17, 2013 10 CFR 50.34 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 NRC Docket No. 50-391

Subject:

WATTS BAR NUCLEAR PLANT (WBN) UNIT 2 - REVISION OF COMMITTMENT FOR INSPECTION AND REPAIR OF KAPTON INSULATED PIGTAILS WITHIN ELECTRICAL CONTAINMENT PENETRATIONS

References:

1. NRC letter dated August 15, 1995, "NRC Inspection Report Nos. 50-390/95-45, 50-391/95-45 and Notice of Violation"

2. TVA letter dated November 14, 1994, "Watts Bar Nuclear Plant (WBN) Unit 1 - NRC Inspection Report No. 50-390, 391/94-61, Reply to Notice of Violations - CDRs 390, 391/94-14 and CDR 390/94-15, Final Report"

3. NRC letter dated October 12, 1994, "Notice of Violation (NRC Inspection Report Nos. 50-390/94-61 and 50-391/94-61)"

4. TVA letter dated September 25, 1989, "Watts Bar Nuclear Plant (WBN) Unit 1 and 2 - Kapton Insulation Penetration Pigtail Damage -

WBRD-50-390/89 Final Report" The purpose of this letter is to revise the WBN Unit 2 commitment for the inspection of electrical penetration Kapton insulation pigtail damage.

..... 7

U.S. Nuclear Regulatory Commission Page 2 December 17, 2013 The inspection of the subject pigtails for damage has evolved since inspection deficiencies were initially identified by TVA (Reference 4). WBN Unit 1 addressed recurring inspection deficiency issues (Reference 2) identified by the NRC that resulted in a Notice of Violation (NOV) (Reference 3) through (1) the development of a specific training program for personnel involved with electrical penetrations; (2) requiring specifically trained personnel to perform the electrical penetration work; (3) site bulletins that were issued to increase awareness of recurring damage to electrical penetration wiring; and (4) the addition of precautionary notes to the applicable vendor manual, WBN existing programs, and work/maintenance procedures.

In addition to the corrective actions (Reference 2) taken by WBN Unit 1 to prevent recurrence and support closure of the NOV (Reference 3), only a final electrical penetration Kapton insulation pigtail damage verification inspection by a TVA Nuclear Engineering (NE) cable specialist or NE designee (References 1 and 2) was implemented. TVA has determined that only the WBN Unit 1 NE cable specialist or NE designee verification inspection process is appropriate for WBN Unit 2. The revised WBN Unit 2 commitment will result in an inspection of the WBN Unit 2 electrical penetration Kapton insulation pigtails for damage utilizing an NE cable specialist or NE designee. In addition, following construction activities at each penetration but prior to installing the protective polyolefin heat shrink on each bundle of cable, a final inspection of each bundle's outside cables will validate that there is no new damage to the Kapton due to current construction activities. The outside of a bundle is the most vulnerable to construction damage. In the event damage is found, the NE cable specialist/NE designee shall inspect the next layer of cables for damage and will continue this process until a layer of cables with no damage is found. A repair sheet will be completed for any damages found, and construction will complete the required repairs with a Quality Control inspector present. TVA has determined that this inspection process is sufficient to ensure that damaged Kapton insulated conductors have been identified and repaired as warranted.

If you have any questions, please contact Gordon Arent at (423) 365-2004.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 1 7 th day of December, 2013.

Respectfully, Raymond A. Hruby, Jr.

General Manager, Technical Services Watts Bar Unit 2 cc: (see page 3)

U.S. Nuclear Regulatory Commission Page 3 December 17, 2013 cc: U. S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 NRC Resident Inspector Unit 2 Watts Bar Nuclear Plant 1260 Nuclear Plant Road Spring City, Tennessee 37381