ML19256C888
| ML19256C888 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 07/20/1979 |
| From: | Klinger G, Mckee P, Reisland J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PNO-79-270, NUDOCS 7910150655 | |
| Download: ML19256C888 (2) | |
Text
p PRELIMINARY NOTIFICATION July 20, 1979 FRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-79-270 This oreliminary notification constitutes EARLY notice of events of POSSIBLE safety or oublic interest sianificance.
The information presented is as initialiy received without verification or evaluation and is basically all tnat.is known by IE staff on this date.,
Facility:
Sacramento Municipal Utility District
~
Rancho Seco Nuclear Power Plant Docket No. 50-312 Sacramento, California Subiect:
RESULTS OF ANA'_YSIS AND TESTING ON CLASS 1 PIPING SUPPORTS D.ancho Seco has partially completed the analysis and testing of piping supports as required by IE Bulletin 79-02.
There are 197 Class 1 piping supports involved. Of these,138 have been determined by analysis to have safety factors greater than 5, 36 have safety factors greater than 2 but less than S,11 have safety factors greater t*an 1 but less than 2, and 12 have not yet been analyzed.
Of the 36 supports having safety factors between 2 and 5, 27 are accessible and hive been tested.
Of the 120 anchors involved, ? failures were identified (insufficient embedment - 1/8" to 1/4" less than required).
Also, 10 anchors were found to be degraded (thread engagement 1/8" less than desired).
These defects have been corrected.
Design modifications are required to upgrade the 11 supports that have safety fa: tors between 1 and 2.
The modifications on 2 of the supports have been ccmpleted.
Modifications for the other 9 supports are scheduled for completion by 7/25/79.
This matter is being evaluated by Region V and NRC Headquarters
(;E and NRR), with a conference call with licensee personnel scheduled for 7/20/79.
Media interest is expected.
The licensee does not plan to issue a news release.
A ne..
V. Stello, IE L. V. Gossick, EDO H. R. Denton,'NRR Region H. L. Ornstein, EDO R. C. DeYoung, NRR J. J. Fouchard, PA R. J. Mattson, NRR N. M. Haller, MPA D. Vassallo, NRR (MAIL)
R. G. Ryan, OSP D. Eisenhut, NRR J. J. Cummings, OIA H. K. Shapar, ELD SS Bldg R. Minogue, SD W. J. Dircks, NMSS S. Levine, RES PRELIMINARY NOTIFICATION o
.