ML19270G641
| ML19270G641 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 04/27/1979 |
| From: | Moody D VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| WVY-79-50, NUDOCS 7906140328 | |
| Download: ML19270G641 (2) | |
Text
i' IM 3
l VERMONT YANKEM NUCLEAR POWER CORPORATION j
r SEVEPsTY SEVEN GROVE 5 s REET l
B4.2.1 I
RUTI.AND, VEttMONT 05701 l
.et, va.
Ef4GINEERING OFFICE t
l TUANPtME ROAD j
wEsToorv. -asuchosurs onsi April 27, 1979 ET 79-50 f
United States helcar Regalatory Cc=1ssica Region I 631 Park Avenue King of Prussia, Pennsylvania 19405 Attention: Inspect 1m aof Enforce:ent Office Boyce H. Grier, Director i
References:
(a)LicenseNo.DP3-28(DocketNo.50-271)
(b) USNRC Letter to VINPC dated April 14,1979; IE h lletin 79-07 (c) VINPC Letter to US;,EC date:i Hay 27, 1971
Dear Sir:
Subject:
Seismic Stress Iralysis of Safety Related Piping In rerpense to ymr letter, Reference (b), we submit the following infer:atien relative to the scistic analyses e: played in the desi&3 of the 7ernant Yankee helear Pcwer Station.
Ites 1, Resomse:
2342 iS8 Ebaseo Servlees, Inc., the Architect Egineer for Ver: nt Tankee, has notified us that all the 7e ont Tadet safety related pipirg they analyzed utilized a static analysis independent of the Stone & i'ebster techniques in question. Hwever, a statement in Reference (c) alludes to i
a dynamic analyses being ecnducted in cases vnere the static stress evalinticri criteria uns not cet. D asco personnel have been ccatacted and are presently inve:tigating if a dyratic analysis was used, and if so, on what systens.
I The piping syste::s sei:::ically analyzed by General Electric were actually perforced by a subcentracter enosen by GE. General Electric Ms ir.for cd us that none of the ethods specified ir. Ita: I wre c:plcyed er used in eo: pater codes for tha sci:::ic analyses of the racirculation or sten systes piping, 790614()4,2 74
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l United States Suclear Zegalatory Comission Page Two April 27, 1979 Ites 2, Respcnsee I
As noted above, to date, na codes have been identified which c plcyed the techniques delineated in Ites 1 of the bulletin. D.erefore, no ec: pater prcgma listings for the dymeic response amlysis particas of the codes will be subsitted. If Dasco's coatinued review identifies any subject techniques, the pmgrae listings of each will be forwarded to you.
Ites 3, Ressmsee Ebasco Services, Inc., and General Electric Cc pany and their i
subcontracter are presently reviewig inferratien relative to checking, bench =arking and caparision teenaiques used to verify the cce;;utar pmgress used in the original design analysis. The results of this revies vill be fccarded to you as soon as it becc es available.
Ites 4, Hes; case:
To date, we have mt identified any of the retiv>ds listed in Ites 1 as havig been coloyed in Zei=ic Catego y I analyses performed for the 7er: ant Yankee piping ryste:s. Taas, we have determined it to be 1:apprcpriate to re-naluate these piping syste s.
If we subsequently identify any met' ds relative to those listed in Ite= 1, we will sub:1t a m
plan of actim and schedale for re-evalmtica.
All piping syste:s ecdificatims and additiens copleted since Ver ent Yankee startus were analy:ed by the Tankee Nuclear,ervice Divisica or under the mrsa vision of Yankee. Tne analyses used m these modifications were equivalent static sc1=ic ar.alyses using either AEIS, er PIPS SD cc puter pregrams. Rase pregm s are standard, proven pmgraer nich have bem brach.ar,:el an1/cr verified for general incastry use.
As erntimed above, cutstanding infer:atitn resacsted by EC will be i
forwarded to you as som as it is received. If ycu require additional Ninfce..atic r on this subject, please contact us at year cor.venience.
j Yery truly yours, VEFKAT YANIEZ.'."JCI.DR PCiTR C3?CET C's h
2342
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