ML20236V362
| ML20236V362 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 08/27/1975 |
| From: | Jennifer Davis, Dreher F, Thornburg H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PN-75-076, PN-75-76, NUDOCS 9808030115 | |
| Download: ML20236V362 (1) | |
Text
)
PDrm)W.6C4 l
l+ 2 hof PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE S
August 27, 1975
{$.-
PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE
--PN-75-76 l
This preliminary notification constitutes EARLY notice of events 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 OIE staff as of 1:30 p.m. on the date of this notification.
IT SHOULD BE SPECIFICALLY NOTED THAT THIS NOTIFICATION MAY CONTAIN INFORMATION THAT LATER MAY BE DETERMINED TO
}
BE INACCURATE OR INCONSISTENT. AN OFFICE OF INSPECTION AND ENFORCEMENT I
NOTIFICATION OF AN INCIDENT OR OCCURRENCE (BLUE SHEET) SUBSEQUENTLY WILL BE ISSUED IF WARRANTED.
' " " ' ~ '
Facility:
Vermont Yankee (DN 50-271)
Subject:
Unisolatable leak in 1-inch instrument line During a drywell inspection with the reactor at operating temperature and pressure, leakage was noted from a recirculation loop riser 1-inch instru-ment line. The leak appears to be a 3/16 inch circumferential crack adjacent to the heat affected zone of a weld at an elbow. The leak is downstream of a flow restricting orifice.
The crack poses no safety l
l related problem.
MM The licensee-will perform metallurgical examinations to characterize the failure mode.
(.==
The reactor is in cold shutdown.
The licensee estimates at least a two day outage to complete this repair and other repair work which was in progress when the leak was found. Region I inspectors are on site.
Media interest is expected because of interest and attention at this plant.
The State of Vermont has been and is being kept informed. A press release is not planned.
OIE received notification of this occurrence by inspector on site from licensee at 10:00 a.m. 8/27/75.
Contact:
FADreher, IE x7261 HDThornburg, IE x7353 JGDavis, IE x7541 Distribution:
Chairman Anders Commissioner Mason S.'J. Chilk, SECY Commissioner Gilinsky Commissioner Rowden G. F. Murphy, JCAE Commissioner Kennedy C. C. Kammerer. CA c~
l l
L. V. Gossick, EDO D. F. Knuth, IE J. A. Harris, PA l
B. C. Rusche, NRR H. H. Brown, ISP T. J. McTiernan, AIA l
K. R. Chapman, NMSS H. K. Shapar, ELD Transmitted: P Bldg.2
- H S t.2,
- MNBB
- Luge,um'[
n-,
PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE 9808030115 750827 PDR I&E PN-75-076 pyg l