ML19031B067

LER 1977-002-01 for Salem, Unit 1, Pipe Failure on Letdown Vent Line

ML19031B067
Person / Time
Site:	Salem
Issue date:	01/28/1977
From:	Schneider F Public Service Electric & Gas Co
To:	O'Reilly J NRC/IE, NRC Region 1
References
LER 1977-002-01
Download: ML19031B067 (4)

Text

Frederick W. Schneider Public Service Electric and Gas Company 80 Park Place Newark, N.J. 07101 201/622-7000 Vice President Production

~\egulatory Docket Fi Mr. James P. O'Reilly Director of USNRC Off ice of Inspections and Enforcements Region 1 631 Park Avenue King of Prussia, Pennsylvania 19406 D~ar Mr. O'Reilly:

LICENSE NO. DPR-70 DOCKET NO. 50-272 REPORTABLE OCCURRENCE 77-02/3L Pursuant to the requirements of Salem Generating Station Unit No. 1 Technical Specifications, Section 6.9.1, we are submitting Licensee Event Report for Reportable Occurrence 77-02/3L. This report is required within thirty (30) days of the occurrence.

Sincerely yours, CC: Director, Office of Inspection and Enforcement (30 copies)

Director, Office of Management Information and Program Control 1033 (3 copies)

Report Number:

Report Date:

Occurrence Date:

• -02/3L 1/12/77 1/03/77 Facility Salem Generating Station Public Service Electric & Gas Company Hancocks Bridge, New Jersey 080~8 IDENTIFICATION OF OCCURRENCE:

• Pipe failure on letdown vent line.

CONDITIONS PRIOR TO OCCURRENCE:

Mode 3 operation, Plant pressure 2235 psig, Plant temperature 547°F.

DESCRIPTION OF OCCURRENCE:

No. 15 Containment Fan Coil Unit leak detection system alarmed and con-tainment humidity increased. Normal letdown was in service. The containment sump pumps started and makeup to the VCT increased. Letdown flow indicated zero while charging flow was normal. Normal letdown was isolated and excess letdown initiated. All indications of a RCS leak terminated. Investigation revealed a pipe break in the letdown vent line ahead of valve 1CV396. Approximately 2400 gallons of reactor cool-ant spilled in the 78' elevation of the containment and drained into the containment sump.

DESIGNATION OF APPARENT CAUSE OF OCCURRENCE:

Excessive vibration of the 3/4" vent line caused the pipe to shear down-stream of the joint to the main letdown line.

ANALYSIS OF OCCURRENCE:

Airborne activity in the reactor containment was less than the maximum permissible concentration. The spilled coolant drained into the contain-ment sump and was pumped to the waste holdup tanks for processing. The leak rate was reduced to less than the Technical Specification limit of paragraph 3.4.1.2 within the allowed time and all action statements were cancelled. At no time was there any danger to the general public or site personnel.

CORRECTIVE ACTION:

The 3/4" letdown vent line was removed. The remaining socket was plugged and welded. NDE was performed on the new weld and the system was hydrostat' ical.ly tested. Ten similar vent lines in the eve System were identi-f ied and NDE was performed on the 3/4" to header welds. No indications were identified.

- - *l Report No. 77-02/3L

• 1/12/77 Page 2

~

FAILURE DATA:

Pipe: 3/4" Schedule 40 ASTM A-403 TP-304 Prepared by T. Spencer SORC Meeting No. 8-77

CONTROL BLOCK

• LICENSEE EVENT REPORT

• 6 LICENSEE LICENSE EVENT NAME LICENSE NUMBER TYPE TYPE REPORT REPORT CATEGORY TYl'E SOURCE COCKET NUMBER EVENT CATE REPORT CATE fOTtl CON'T lE.lQj l.1J L!!.J ~p I 51 0 I -I 0 I 2 I 71 2J !Oili'Oi317171 I750 111 1 I. 2 I 7 17J t-1 57 5B 59 60 69 74 EVENT DESCRIPTION

@n]IDuring Mode 3 operation. nopnal letdown in service. a pipe break occurred!

1 89 ao

@)) in a vent line on the letdown header. Alternate letdown was available.

7 8 9

@El 2400 gal of coolant leaked into the containment sump. Vent line was re-7 8

[Q]i]!moved, plugged and welded. Hydrostatic test was satisfactory. This is I 7 8 9 . 80

~1the first occurrence of this type. (76-02/3L) 1-7 8 9 SYSTEM CAUSE PRIME COMPONENT COMPONENT ao COOE COOE COMPONENT CCOE SUPPLIER MANUFACTURER VIOLATION

@ill tR.J£j lEJ IZ I Z I Z I Z I Z-1ZJ llJ IU 10 18 10 I l.NJ 7 8 9 10 11 12 17 43 44 47 48 CAUSE DESCRIPTION

~1 Excessive vibration caused failure of 3/4" Sch. 40 yent line 9 Simi 1 ar so I

~I8 9uQut 7

liuei;; uuc;1e:r:weut NDE. No indications noted ..

ao I

[Ifil':--~__,..~~--~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

1 89 ao FACILITY METHOO OF STATUS 'JloPOWER OTHE*R STATUS CISCOVERV OISCOVERV CESCRIPTION

[ill] l,gJ. 10 10 10 I NIA I LJ I Ni8 I 1 a. g 10 12 13 44 45 46 80 FORM OF ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY LOCATION OF RELEASE 0!J 7 8 9

~ ~

10 I

11 N/A 44 I I45 N/A so I

PERSONNEL EXPOSURES r:r.:I NUMBER TYPE CESCRIPTION l..!.l:..11010101 lk,J l~~----N~/~A __________________________________- - ; d 7 8 9 11 12 13 sJ PERSONNEL INJURIES NUMBER CESCRIPTION

~I 0 I 0 I 0 I I N/A I 7 8 9 h 12 so OFFSITE CONSEQUENCES rtrsl I N/A

~9 .

LOSS OR DAMAGE TO FACILITY J

TYPE OESCRIPT*ION

~IZI I N/A 7 8 '§'""" 10 J 80 ao 80 NAME: _ _ _ T_._L_._S-=p_e_n_c_e_r__________ PHONE: (609) 365-7000 Ext.Salem- 528 1

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