ML032900938
| ML032900938 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 10/08/2003 |
| From: | Salas P Tennessee Valley Authority |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML032900932 | List: |
| References | |
| Download: ML032900938 (3) | |
Text
October 8, 2003 10 CFR 50.50(a)(3)(ii)
U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 Gentlemen:
In the Matter of Docket No. 50-327 Tennessee Valley Authority SEQUOYAH NUCLEAR PLANT (SQN) - UNIT 1 - CHANGE TO A COMMITMENT ASSOCIATED WITH REQUEST FOR RELIEF FROM AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) CODE FOR REPLACEMENT OF ASME CODE CLASS 3 PIPING
References:
Request for Relief from American Society of Mechanical Engineers (ASME) Code for Replacement of ASME Code Class 3 Piping
- 2) TVA letter to NRC dated June 14, 2003, Sequoyah Nuclear Plant (SQN) - Supplemental Information for Request for Relief from American Society of Mechanical Engineers (ASME) Code for Replacement of ASME Code Class 2 Piping The purpose of this letter is to inform you of a revision to a TVA commitment previously provided in reference 1. The TVA commitment is associated with a pin-hole leak on an 8-inch diameter carbon steel pipe in the essential raw cooling water system. The original TVA commitment as stated in enclosure 2 of reference 1 reads as follows:
U.S. Nuclear Regulatory Commission Page 2 October 8, 2003 TVA will replace the effected piping in accordance with the American Society of Mechanical Engineers code prior to startup from the Unit 2 Cycle 12 refueling outage (currently scheduled to begin November 2003).
Due to material procurement scheduler constraints, TVA is now planning to modify the effected piping to completely remove the existing flaw and restore the piping to meet ASME Code Class 3 pressure boundary requirements. The modification consists of drilling out the degraded area to fully remove the flaw (which is a pinhole leak attributed to micro-biological induced corrosion) and weld an engineered fitting (i.e., pipe cap or branch connection) to the outer wall of the pipe. This modification will restore the structural integrity of the pipe to original design and ASME Code pressure boundary requirements.
Accordingly, TVA is revising the original commitment to read as follows:
TVA will modify the effected piping in accordance with the American Society of Mechanical Engineers code prior to startup from the Unit 2 Cycle 12 refueling outage (currently scheduled to begin November 2003).
Leakage from the pipe continues to be less than one gallon per minute. TVA is continuing weekly walkdowns and quarterly ultrasonic examinations in accordance with commitments in the reference 1.
This letter is being sent in accordance with NRC RIS 2001-05.
If you have any questions about this change, please telephone me at (423) 843-7170 or J. D. Smith at (423) 843-6672.
Sincerely, Original signed by:
Pedro Salas Licensing and Industry Affairs Manager cc: See page 3
U.S. Nuclear Regulatory Commission Page 3 October 8, 2003 cc: Mr. Michael L. Marshall, Jr., Senior Project Manager U.S. Nuclear Regulatory Commission Mail Stop O-8G9A One White Flint North 11555 Rockville Pike Rockville, Maryland 20852-2739