ML19256C620
| ML19256C620 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 04/20/1979 |
| From: | Bryan S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PNO-79-088, PNO-79-88, NUDOCS 7910100622 | |
| Download: ML19256C620 (1) | |
Text
N PRELIMINARY NOTIFICATION April 20,1979 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-79-88 This' preliminary notification constitutes EARLY notice of an event of POSSIBLE safety or public interest significance.
The information presented is as initially received without verification or evaluation and is basically all that is known by IE staff on this date.
FACILITY:
Virginia Electric and Power Company North Anna, Units 1 and 2 Docket Numbers59-338 and 50-339 Mineral, Virginia
SUBJECT:
PROBLEM IN R5 ANALYSIS OF PIPING STRESSES Stone and ':.bster (S&W), during reanalysis of main steam piping, found that stress analysis assumptions used for Unit 1 were also used for Unit 2.
Since Unit 2 main steam valve housing (MSVH) has a soil foundation, while Unit 1 MSVH is founded on rock, response character-istics are different and more severe for Unit 2 piping in the MSVH.
The reanalysis also indicated that incorrect displacement assumptions were used in the pipe loading in the MSVH on Unit 1.
The incorrect displacements involve 26 pipe hangers in 3 safety-related systems.
Presently, Unit 1 is in cold shutdown and Unit 2 is in preoperational testing.
Local media interest is expected due to the close attention given to activities at this site.
A news release is not planned by the licensee or the NRC.
The Commonwealth of Virginia has been informed.
Region II (Atlanta) received notification of this information by telephone from the Resident Inspector at 10:00 a.m. on April 20.
Contact:
S. E. Bryan, IE x28019 Distribution:
Transmitted H St 2.*d Chairman Hendrie Commissioner Bradford S. J. Chilk, SECY Commissioner Kennedy Commissioner Ahearne C. C. Kammerer, CA Commissioner Gilinsky (For Distribution) e Transmitted:
MNBB 2.M P. Bldg 3(CS J. G. Davis, IE L. V. Gossick, ED0 H. R. Denton, NRP, Region 1 j7/o 2 H. L. Ornstein, EDO R. C. DeYoung, NRR J. J. Fouchard, PA R. J. Mattson, NRR N. M. Haller, MPA V. Stello, NRR (MAIL)
R. G. Ryan, OSP R. S. Boyd, NRR J. J. Cummings, 0IA l
H. K. Shapar, ELD SS Bld9 2 J i~/
R. Minogue, SD W. J. Dircks, NMSS S. Levine, RES
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\\4' PRELIMINARY NOTIFICATION 7910100 2