ML19275A694
| ML19275A694 | |
| Person / Time | |
|---|---|
| Site: | 05000363 |
| Issue date: | 09/27/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Finfrock I JERSEY CENTRAL POWER & LIGHT CO. |
| References | |
| NUDOCS 7910180127 | |
| Download: ML19275A694 (1) | |
Text
- ' \\py* "%,j%,
fg i
UNITED STATES 8 (} ') e (-[ g NUCLEAR REGULATORY COMMISSION 3 j',[j/.. j REGION 1 S j's g
631 PARK AVENUE
% ' b' KING OF PRUSSIA, PENNSYLVANIA 1940G 9.....,o Docket No. 50-363 sip 27 @
Jersey Central Power & Light Company ATTN:
Mr. I. R. Finfrock, Jr.
Vice President 260 Cherry Hill Road Parsippany, New Jersey 07054 Gentlemen:
The enclosed Bulletin 79-24 is forwarded to you for information. If you desire additional information regarding this matter, please contact this office.
Sincerely, sere #f.
~
oyce H. Grier Director
Enclosures:
1.
List of IE Bulletins Issued in the Last Six Months cc w/encls:
M. K. Pastor, Project Manager 1185 130 7910180 g
ENCLOSURE 1 Accession No. 7908220114 SSINS No:
6820 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE Bulletin No. 79-24 Date:
September 27, 1979 Page 1 of 2 FR0 ZEN LINES Summary:
On January 3, 1979, an unusual event occurred at Davis-Besse, Unit 1.
The event involved the freezing of the water in a portion of the high pressure coolant injection (HPCI) system recirculation line that is common to both high pressure coolant injection pumps.
The line was not thawed until January 5, 1979, and the event was not reporten to NRC until March 12, 1979.
In addition, over the past five years, there have been several events involving frozen instrument and sampling lines.
Description of Circumstances:
The condition was discovered on January 3, 1979, while the reactor was operating at approximately 96 percent power.
During a monthly surveillance test of the HPCI pumps, there was no flow through the recirculation line from the pump discharge to the Borated Water Storage Tank (BWST).
Investigation revealed that water in a portion of the line exposed to the outside weather was frozen.
This portion of the line to the BWST is common to both HPCI pumps.
The line has redundant heat tracing (a heated wire tn prevent freezing); it is insulated; and it has a low-temperature alarm system to warn of freezing conditions.
Water in the line froze apparently because of prolonged sub-freezing temperatures and a defect in the insulation.
There was no apparent malfunction of the heat tracing or temperature alarm circuits, although the temperature sensing elements are located in an area not exposed to the coldest temperature conditions.
This recirculation line serves two purposes:
Onc is to provide a flow path for surveillance testing, and the other i:, to provide a minimum flow path to prevent possible damage to the pump in the event it is operated against a closed discharge valve or a reactor coolant system pressure greater than the maximum discharge pressure of the pump (approximately 1600 psig).
In the initial review of the event on January 3, 1979, the licensee concludad that the pumps were still operable with no immediate action was taken to thaw tl January 5, 1979, the line was thawed anc was successfully completed.
DUPLICATE DOCU!ENT Entire document previously l
g:-
9yI,) ;I entered into system under:
Ud ANO No. of pages: