ML20055F615
| ML20055F615 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 07/13/1990 |
| From: | Wallace E TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-88-010, IEB-88-10, NUDOCS 9007180170 | |
| Download: ML20055F615 (2) | |
Text
g,m My
.g b$
A y
it-3, #.
TENNESSEE VALLEY AUTHORITY-fp CHATTANOOGA, TENNESSEE 374ol 4;
-5N 157B Lookout Place K'9 JUL 131990
- f 5
U.S. Nuclear Regulatory Commission l
-ATTN:' Document Control Desk
-Washington, D.C..
20555 Gentlemen:
y
't In the Matter of-'
)
Docket Nos. 50-327 Tennessee Valley Authority
)
50-328 1
y'
-SEQUOYAH NUCLEAR' PLANT (SQN) - NRC BULLETIN 88-10 NONCONFORMING MOLDED-CASE 1
' CIRCUIT BREAKERS 4
References:
'1.
TVA' letter to NRC dated March 20, 1990, "Sequoyah Nuclear e
Plant (SQN) - NRC Bulletin 88-10, Nonconforming Molded-Case
' Circuit Breakers" a.
j
- 2. 'TVA letter to NRC dated February 10, 1988, "Sequoyah Nuclear 0
Plant (SQN) - Replacement' Items Program-(RIP) Supplemental Program. Plan" 7(
In Reference'1,'TVA proposed no further reviews to identify maintenance direct-charge, molded-case circuit breakers procured between August 1983 and r
3
-December >1984_
1 The proposal was based upon the resource-intensive search'of records that would be required, the' high expectation that a quite small number of direct-charge breakers would be :Identifled, and the high probability. that csurveillance~ testing was performed at the time of replacement. This submittal provides-additional bases'for TVA's proposal.
i
' TVA'has reviewed the -list' of molded-case circuit breakers that were identified 4
asiuntraceable for SQN.- Of the 250 breaker installations, only 3 were gidentified for the August 1983 -to December 1984 period, and none of these were
' maintenance direct-charge-breakers. There we're'247' breaker. replacements:
4
'procuredLbetween. January 1985 and August 1988 Out of these 247 breakers, 32 (13 percent) were maintenance direct-charge breakers.
(This distribution can-
'best'be explained by the fact.that the SQN restart' effort between 1985 and
' 1988 included several major modifications resulting fror the electrical
-calculations-review and-the ampacity issue.) The sme' atio of 1985 to 1988 i
period.' direct-charge breakers to the total 1985 to 15 4 period breakers, and the:very small number-of,1983 to 1984 stock replacemei..s. suggest that the total' number of direct-charge installations for August 1983 to December 1984=
- would also be quite small.
Additionally as noted in Reference 2, results from SQN's RIP indicate that
- 93. percent of maintenance replacements historically come from stock; the s
remaining 7 percent come from direct-charge procurement. This, too, supports the conclusion that there should be very.few maintenance direct-charge breaker replacements from August.1983 to December:1984.
i 9007180170 900713 il PDR ADOCK 05000327
/,
- o PDC
/\\
An Equal Opportunity Employer
)
RJ
.t
~' -
~
py 1% i J3 3
w
- , ; r u
c:
m-a h U.S. Nuclear Regulatory Commission 9
' {:
- TVA has also reviewed the contracts that purchased molded-case circuit breakers for SQN from'1983 to 1988. Of the 961 breakers purchased, only 52 breakers (less than six percent) were procured in 1983 and 1984.- There f
were-909 breakers procured from 198b to 1988. The small number of total j
breakers procured in 1983 and 1984-is another supporting basis for expecting 1
very few direct-charge breaker installations from August 1983 to December 1984
.p A preliminary review of TVA records indicates that approximately 15,000 work requests would'have to be retrieved and evaluated to identify any additional w
direct-charge maintenance breaker replacements for the August 1983 to j
becember 1984 period. TVA has concluded that no significant assurance would e
.be expected from the' additional resource expenditures, m
~
No commitments are contained in this submittal.- The information provided has been previously discussed by telephone with NRC staff.
Please direct questions concerning this issue to Kathy S. Whitaker at (615) 843-7748.
- Very truly yours,
- [
v i
TENNESSEE VALLEY AUTHORITY
- h. /
1 E
G. Wallace, Manager
?
Nuclear' Licensing and i
-Regulatory Affairs
'l ec:
Ms. S. C. Black, Deputy Director Project Directorate II-4 1
p
[U.S.NuclearRegulatoryCommission f:[
~
L
-One White Flint, North 11555 Rockville Pike j
Rockville, Maryland 20852 1
Jack N. Donohew
(
U.S. Nuclear Regulatory Commission One-White Flint, Not' 11555'Rockville Pike l
Rockville, Maryland' 20852-s NRC Resident Inspector Sequoyah Nuclear Plant 2600 Igou Ferry Road 1
i Soddy Daisy. Tennessee 37379 i
Mr. B.rA.' Wilson.-Project Chief U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900
-Atlanta, Georgia 30323 vi:
.j