ML20037C746
| ML20037C746 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 02/13/1981 |
| From: | Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| RO-3-81-8-1P, NUDOCS 8102200456 | |
| Download: ML20037C746 (2) | |
Text
U-
' f PHILADELPHIA ELECTRIC COMPANY
. Peach Botton Atomic Power Station Delta,. Pennsylvania 17314 February 13, 1981 Mr. Boyce H. Grier Office of Inspection and Enforcement Rogion 1 United States Nuclear Regulatory Commission 631 Park Avenue Klag of Prussia, PA 19406
SUBJECT:
REPORTA3LE OCCURRENCE PROMPT NOTIFICATION Confirming R.
S.
Fleischmann's conversation with Mr. Cowgill on Fobruary 11, 198t.
Roference:
Docket No. 50-278 Peach Botton Unit 3 Technical Specification
Reference:
3.~.A.2 5 6.9.2a(3)
Roport No. 3 31-S/IP.
Occurrence Date.
February 11, 1931 Identification of Occurrence:
During the installation of a new penetration test connection to a containment atmospheric dilution line, primary containment integrity was breached for a short time period.
With the unit at
-ntially full load, permission vas obtained from the operacing gr.,
so i r. s t a l l a new test connection on the CAO con-teinment penetration.
The operating group had supposedly losiated the section of piping to be codified by closing the sanual valve botween containment and the location where the pipe was to be cut.
Due to an incorrect location identification for the manual valve on a system check-off list, the operator closed the manual isolation volve on the
'S' CAD loop instead of the isolation valve on the
'A' icop which was being modified.
Construction then proceeded to cut the
'A' loop 1" piping and install a 1"
socket-weld Tee connection.
In attempting to make the closure veld on this new Tee, the slight differential pressure which existed between primary containment and secondary containment alerted the craftsman to the error.
Pri=ary containment was breached for less than 90 minutes.
((00 Conditions Prior to the Occurrence:
Unit 2 operating at essentially full power.
Apparent Cause of occurrence:
Icproper designation of valve location on a system procedure resulted.
81 0 220 0Yh 6
- 1
+
in an operator being dzrected to close a manual containment isolation volve on the incorrect loop.
The isolation valves in this location did not have identification tags.
Analysis o f O c c u r r e n c _e_ :
Primary containment was breached to secondary containment fo r opproximate y 90 minutes.
Differential pressure between primary containment and secondary containment was very small, thereby cinimi-ing leakage and making it difficult to identify the valving orror immediately upon cutting the 1"
pipe.
The 1" pipe was cut in tuo locations and a socket weld Tee with the test connection and valves already fabricated was inserted.
Leakage from containment was, there-fore, minimum during this 90 minute period.
A manual valve was available between containment and the cut which would have permitted isolating this line quickly had a significant dif feren tial pressure between primary and secondary containment occurred.
Containment integrity was recovered after the probles was
.d en t i fied.
Corrective Action:
Icmediate corrective action was taken to isolate the leak by closing the inboard manual isolation valve.
This re-established p r i= 2 ry c o n t a i nme r, t integrity.
Until the valving associated with this work could be corrected, both containment atmospheric dilution penetrations were isolated.
This condition is permissible for a period of 30 days in a c c o rd a n c e with paragraph 3.7.A.6.a.
Operabiltty of the
'B' CAD system was re-established within one hour.
Additional corrective action associated with correcting the eqbiprent location on the system procedure and installation of identification tags on these valsas will be completed in the near future.
Previous Failures:
None siellar.
'Tery truly yours, MAW d k.
T.
Ullrich Station Superintendent WTU:1ja
.