ML20248E825
| ML20248E825 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 10/03/1989 |
| From: | Michael Ray TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-88-008, IEB-88-8, NUDOCS 8910060038 | |
| Download: ML20248E825 (2) | |
Text
_ _.
TENNESSEE VALLEY AUTHORITY
' CHATTANOOGA, TENNESSEE 37401 SN 157B Lookout Place 00T03388 U.$. Nuclear Regulatory Commission ATTN: Document Control Desk
'Hashington, D C.
20555 Gentlemen:
In the Matter of
)
Docket Nos. 50-327 Tennessee Valley Authority
)
50-328 SEQUOYAH NUCLEAR PLANT (SQN) - N'4C BULLETIN 88-08, THERMAL STRESSES IN PIPING CONNECTED TO REACTOR COOLANT SYSTEMS
References:
1.
TVA letter to NRC dated August 24, 1988 2.
TVA letter to NRC dated.lanuary 10, 1989 This letter provides Revision 2 :o TVA's response to Bulletin 88-08 for SQN-Units 1 and 2.-
In~ Reference 1. TVA identified seven sections of unisolable piping that could be subjected to thermal stresses. Reference 2 revised the original response by identifying two of the seven sections of piping, the 3-inch alternate charging path and the 3-inch normal charging path, that should not be subjected to thermal stresses.
TVA has now determined that the four 1.5-inch high-head injection. lines will not be subjected to thermal stresses subsequent to the boron injection tank (BIT) bypass removal. This removal is currently scheduled for the Unit 1 Cycle 4 and Unit 2 Cycle 4 refueling outages.. Double isolation of the injection lines from the charging pumps will be provided by the four normally closed BIT isolation valves for each utilt.
Additionally, the 2-inch pressurizer spray line from the charging path should not be subjected to thermal stresses. The differential pressure is low, approximately seven pounds per square inch differential, and a reliable pressure boundary exists. There also is a cold trap downstream of the last check valve, and the inleakage temperature would only be approximately 495 degrees Fahrenheit.
Based on the'above information, TVA does not intend to monitor any piping for thermal stresses on SQN Unit 1.
The monitoring equipment currently in place on Unit 2 will no longer be required when BIT removal is complete.
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An Equal opportunity Employer
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' OCT 03M U.S. Nuclear Regulatory Commission.
t No commitments are contained in this submittal. Please direct questions concerning this issue to Kathy S. Whitaker at (615) 843-7748.
L Very truly yours, TENNESSEE VALLEY AUTHORITY M. J. Ray, Ma1ager Licensing Project Management Swornjo d.subscr d efore me.
this d day of 1989 n
NoFary'Public My Commission Expires cc: Ms. S. C. Black, Assistant Director for Projects TVA Projects Division U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 Mr. B. A. Wilson, Assistant Director for Inspection Programs
-TVA Projects Division U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 NRC Resident Inspector Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy Daisy, Tennessee 37379 l
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