ML20084G040
| ML20084G040 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 05/26/1995 |
| From: | Shell R TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TAC-91988, TAC-91989, NUDOCS 9506020408 | |
| Download: ML20084G040 (2) | |
Text
(
o?e IUA lennessee Vailey Aut y Post Ottce Bos 2000. Soddy Dasy Tennessee 37379 May 26,1995 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 Gentlemen:
In the Matter of
)
Docket Nos. 50-327 Tennessee Valley Authority
)
50-328 SEQUOYAH NUCLEAR PLANT (SQN) - ADDITIONAL INFORMATION TO TECHNICAL SPECIFICATION (TS) 94-19, " ELIMINATION OF UNNECESSARY DIESEL GENERATOR (D/G) STARTS" (TAC NOS. 91988 AND 91989)
Reference:
TVA letter to NRC dated April 6,1995, "Sequoyah Nuclear Plant (SON) - Technical Specification (TS) Change 94-19, ' Elimination of Unnecessary Diesel Generator (D/G) Starts" As requested by NRC staff, this letter provides additional justification :or the subject proposed TS change. Specifically, additional justification has been requested with respect to the acceptability of relaxing the 24-hour test requirement for the operable D/Gs in the absence of common cause failure.
TVA considers the frequency specified by Table 4.8-1 for Surveillance Requirement 4.8.1.1.2 of the SON TSs to provide adequate assurance of D/G operability. This position is supported by the overall reliability of the D/Gs.
Note that the last D/G reliability data report for 1994 was submitted to NRC on February 22,1995. This report indicated that there were two valid failures for 190 D/G starts; one valid failure has subsequently been removed, implementation of the maintenance rule will further ensure that D/G reliability remains high. Based upon the D/G reliability exhibited at SON, the probability of failure of a redundant D/G during the time that the other D/G is inoperable is judged to be sufficiently low.
020018 pD) p 9506020408 950526 PDR ADOCK 05000327 P
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U.S. Nuclear Regulatory Commission Page 2 May 26,1995 Please direct questions concerning this issue to J. D. Smith at 843-6672.
Sincerely, R. H. Shell Manager SON Site Licensing cc: Mr. D. E. LaBarge, Project Manager Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852-2739 NRC Resident inspector Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy-Daisy, Tennessee 37379-3624 Regional Administrator U.S. Nuclear Regulatory Commission Region ll 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323-2711 l