ML18113A759

LER 78-046/03L-0 on 781211:during Routine Surveillance, Discovered Failure of Heat Tracing Circuit 25A (Panel 2) Unit 1 Boron Injection Tank Recirculation to Boric Acid Tank.Caused by Boric Acid Attack on Heat Tracing Circuit

ML18113A759
Person / Time
Site:	Surry
Issue date:	01/02/1979
From:	BAUCOM T L VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML18113A757	List: ML18113A756 ML18113A758 ML18113A759 ML18113A760
References
LER-78-046-03L, LER-78-46-3L, NUDOCS 7901090230
Download: ML18113A759 (2)

Text

NRC FORM 366 17-7:J) U.S. NUCLEAR REGULATORY COMMISSION

' elCENSEE EVENT REPORT e CONTROL t:!LOCK: LI _..____,_~-'--'-----....JI 0 (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION) 1 6 I v I A I s IP Is I 1 101 o I ol -Io Io I o I o I o I -Io Io 101 41 1 I 1 I 1 I 1101 I 10 7 8 9 LICENSEE CODE 14 15 LICENSE NUMBER

• 25 26 LICENSE TYPE ;JO 57 CAT 58 CON'T 7 8 L!JG) I o I s I o I o I o I 2 I 8 I o 1011 I

• 2 I 1 I 1 I 1 I 8 101 o I 1 I a I 2 I 1 I 9 I G) 60 61 DOCKET NUMBER 68 69 EVENT DATE 74 75 REPORT DATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES@

I During normal operation_, routine surveillance revealed the failure of heat tracing circuit 25A (panel 2h Unit #1 boron injection tank recirc. return to boric acid tank. I This is a degraded mode of operation permitted by T.S. 3.3.B.5 and is reportable as l]]:IJ I per T.S. 6.6.2.B. (2). The health and safety of the public were not affected.

IT]]] 7 8 9 ITII] 7 8 SYSTEM CAUSE CAUSE COMP. VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE I SI HI@ ~@ ~@ I HI EI A I TI E I R 1@ ~@ LU@ 9 10 11 12 13 18 19 20 @ LE R/RO CV ENT YEAR SEQUENTIAL OCCURRENCE REPORT . REPORT I 7 I 81 . l.==.I NUMBER 21 22 23 ACTION FUTURE EFFECT SHUTDOWN TAKEN ACTION ON PLANT METHOD . REPORT NO. CODE TYPE I Oj 4/6 I j/j I O I 3 I l.=J 24 26 27 28 29 30 31 PRIME COMP. HOURS SUBMITTED NPRD-4 FORM SUB. SUPPLIER REVISION NO

• 32 COMPONENT MANUFACTURER 80 l.U@LU@ ~@ ~ 33 34 35 36 37 @ ATTACHMENT OJO I Oj I L':J@ 40 41 ~ ~@ 1c1 216 JB !@) CAUSE DESCRIPTION AND CORRECTIVE ACTIONS @ 42 43 44 47 .. l _A_r_e_v_i_ew

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a ___ _.! attack on the heat tracing circuit. The corrective action implemented was to replace £III] .I the heat tracing tape. ITTIJ 7 8 ... 9 FACILITY STATUS % POWER OTHER STATUS till] W@ I 1 IO IO !@)._I __ NA ___ ___. 10 12 13 CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY ITEJ w @) W@._I _ _..::.;N=A

_____ __. 7 8 9 10 11 8 9 . ACTIVITY 7 44 44 PERSONNEL EXPOSURES . r:;;;,. 80 METHOD OF A DISCOVERY DISCOVERY DESCRIPTION

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45 46 . _LOCATION OF RELEASE@ 80 NA 45 80 NUMBER TYPE DESCRIPTION 8!J j O l O IO lLJ@),___=NA=----~--------------------~

7 8 9 11 12 13 PERSONNEL INJURIES NUMBER DESCRIPTION~

EliJ I O J O IO l@.__ ___ -=N=A=-------------------------~

7 8 9 11 12 LOSS OF OR DAMAGE TO FACILITY '43' TYPE DESCRIPTION

\!.;:J W@ . NA 80 80 7 8 9 10 so PUBLICITY r:-;;,,. ISSUED~ DESCRIPTION~

'( 9 0 1 0 9 O ~3D NRC USE ONLY "' ITli] NA I I I !. I I I I I I I I I 7 8 91 --0-------------------------------~68 69 NAME OF PREPARER T. L. Baucom PHONE: ;1(804) 357-3]84 80 0: 0 0. t, (Attachment, page 1 of 1) Surry Power Docket No: Report No: Event Date: Station, Unit 1 50-280 78-046/03L-0 12-11-78 e Title of Report: Low Current on Heat Tracing 1. Description of Event: e With the unit in normal operation at rated power, routine surveillance found that heat tracing circuit 2:SA (panel 2) was operating at less than the current* specified in the surveillance document.

No low temperature alarms were indicated.

Investigation for faulty heat tracing tape was initiated.

Faults were found on circuit 25A (panel 2) Unit 1 boron injection tank recirculation turn to boric acid tank, and were identified as being the result of boric acid attack on the tape. The tape was replaced and circuit current verified to be within specs of the surveillance document.

This is a degraded mode of operation permitted by T.S. 3.3.B.5 *and is r~portable in accordance with Technical Specif1cation 6.6.2.b.(2).

2. Probable Consequences and Status of Redundant Systems: At all times during the event, the temperature of the affected line was maintained as required.

The redundant circuit was operable.

There was at all times two operable flow paths for boric'acid to the reactor. Therefore, the health and safety of the public were not affected.

3. Cause: The reduced currents were due to boric acid damage to the heat tracing tape on the affected circuit. 4. Immediate Corrective Action: The heat tracing tape was replaced.

5. Scheduled Corrective Action: The problem was corrected immediately and no further action is required.

6. Action Taken to Prevent Recurrence:

Continuous surveillance is maintained on _the Heat Tracing System. No additional action is considered necessary.

7. Generic Implicaticns:

This failure~ as with .others in the system, is considered random since no specified circuit has exhibited repeated failure.