ML17342B020

LER 87-024-00:on 871008,temp for Boric Acid Heat Tracing Circuit Number 6 Decreased Below 145 F.Caused by Cold Flushing of Crosstie Line.Flushing of Boric Acid Pump Crosstie Line Stopped & Sys Alignment restored.W/871109 Ltr

ML17342B020
Person / Time
Site:	Turkey Point
Issue date:	11/09/1987
From:	Wager V, Woody C FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
L-87-453, LER-87-024-01, LER-87-24-1, NUDOCS 8711160102
Download: ML17342B020 (7)

Text

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REGULA Y INFORMATION DISTRIBUTI SYSTEM (RIDS)

ACCESSION NBR: 8711160102 DOC. DATE: 87/1 1/09 NOT*R IZED: NO DOCKET FACIL: 50-251 Turkey Point Planti Unit 4I Florida Poeer and Light C 05000251 AUTH. NAME AUTHOR *FFILIATION WAGER'. Florida Power & Light Co.

WOODY'. O. Florida Power & Light Co.

RECIP. NAME RECIPIENT AFFILIATION

SUBJECT:

LER 87-024-00: on 871008. te'mp for Boric Acid Heat Tracing Circuit Number 6 decreased beloe 145 F. Caused bg cold flushing of crosstie line. Flushing of boric acid pump crosstie line stopped & sos alignment restored. W/871109 itr.

DISTRIBUTION CODE: IE22D COPIES RECEIVED: LTR J TITLE: 50. 73 Licensee Event Report (LER) i Incident Rpti ENCL g etc.SIZE:

NOTES:

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-2 LA 1 PD2-2 PD 1 1 McDONALD> D 1 1 INTERNAL: ACRS MICHELSON 1 1 ACRS MQELLER 2 2 AEQD/DQA 1 AEOD/DSP/NAS 1 1 AEQD/DSP/ROAB 2 2 AEOD/DSP/TPAB 1 1 ARM/DCTS/D*B 1 1 DEDRQ 1 1 NRR/DEST/*DS 1 0 NRR/DEST/CEB 1 1 NRR/DEBT/ELB 1 1 NRR/DEST/ICSB 1 1 NRR/DEST/MEB 1 NRR/DEST/MTB 1 1 NRR/DEST/PSB 1 1 NRR/DEST/RSB 1 1 NRR/DEST/SGB 1 1 NRR/DLPG/HFB 1 1 NRR/DLPG/GAB 1 NRR/DOEA/EAB 1 1 NRR/DREP/RAB 1 1 NRR/DREP/RPB 2 2 NRR/D /SIB 1 1 NRR/PMAS/ILRB 1 1 IL 02 1 1 RES DEPY GI 1 1 ES TELFQRDi J 1 1 RES/DE/EIB 1 1 RGN2 FILE 01 1 1 EXTERNAL: EG&G GROHIM 5 5 H ST LOBBY WARD LPDR 1 1 NRC PDR NSIC HARRISI J 1 NSIC MAYST G TOTAL NUMBER OF COPIES REQUIRED: LTTR 45 ENCL 44

NRC Form 345 U.S. NUCLEAR REOULATORY COA%IISSION (94)3) APPROVED OM 5 NO. 31400104 EXPIRES: 4ISIIBS LICENSEE EVENT REPORT tLER)

FACILITY NAME (II DOCKET NUMBER (2)

Turkey Point Unit 4 0 5 0 0 o 2 5 1 i oF 0 3

'TITLE (4)

Boric Acid Heat Tracing Circuit Number 6 Decreases to Less Than 145 Degrees EVENT DATE ISI LER NUMBER (4) REPORT DATE (7) OTHER FACILITIES INVOLVED (4)

YEAR EEOVENTIAL R4Vt) ION MONTH OAY YEAR FACILITYNAMES DOCKET NUMBER(s)

MONTH DAY YEAR @$ NVMSER NVMEEII N/A 0 5 0 0 0 1 0 0 8 8 7 8 7 024 0 0 0 9 8 7 N/A 0 5 0 0 0 THIS REPORT IS SUBMITTED PURSUANT T 0 THE REQUIREMENTS OF 10 CF R (It (Choco one or more ot tne Ioiioryincl 111)

OPERATINO MODE (4) 20.402(b) 20.405(c) 50,73(a) (2) (Ia) 73.71(b)

POWER 20.405 (a) llI (5 SODS lc) (I I 50.73(a)(2 )ix) 73.71(c)

LEVEL OTHER ISpecity In Abttract 1 p p 20.405 (a I (I I (4 I SOM(cl(21 50.73(a)(2) (YE) below end In Text, HRC Form 20.405(all)I(rII) X '50,73(a)(2) (I) 50.73(a)(21(YIII)(A) 366AI 20AOS(a) lllltx) 50.73(a)(2)(EI 50,73(a) (2) (x(4 (5 I 1

20.405( ~ I (I I (el 50.73(a)(2) (III) 50.73(aH2) I a)

LICENSEE CONTACT FOR THIS LER ('12l NAME TELEPHONE NUMBER AREA CODE Virgi'~ager, Licensing Engineer 305 2 46 -64 76 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

CAUSE SYE 7MPONENT MANUFAC TURER REPORTABLE TO NPRDS lN~(! CAUSE SYSTEM COMPONENT MANUFAC.

TVRER EPORTABL TO NPRDS

?c iyai ..........k.....

FE SPT OCTO. r Hn N :I.'.3yiWMh:

a%%5~~ ..%Ã '~iR SUPPLEMENTAL REPORT EXI'ECfEO l14) MONTH OAY YEAR EXPECTED SV 5 M I SS ION DATE (15)

YES IIIyn, compiete EXPECTED SVB4IISSIDH DATEI X No ABSTRACT ILimit to I400 tpecer, I.e., approximately fitteen tincle.t'pace typewritten Iineai 114)

At '0, on October 8, 1987, with Unit 4 in Mode 1 at lOOX power, the tern ature for Boric Acid Heat Tracing Circuit Number 6 (HT-6), decreased be )45 degrees fahrenheit. This circuit is located on the crosstie pip Ig and valves between the 4A and 4B Boric Acid pumps, and on the pump s discharge line to the inlet of the Unit 4 Boric Acid Filter.

Preparations were made to shut down the unit as required by Technical Specification (TS) 3.0.1. The temperature decrease occurred during the time the 4B Boric Acid pump crosstie line was being flushed to facilitate maintenance work on valve 4-374. The flushing was stopped and the system was restored to the normal alignment. A blended makeup flow was pumped through the boric acid flowpath to verify that there was no blockage in the pipe and to assist with the temperature increase in the circuit.

At 1915, the temperature started increasing and continued to increase steadily until it was above 145 degrees at 2007 hours0.0232 days <br />0.558 hours <br />0.00332 weeks <br />7.636635e-4 months <br />. Also found as a part of the investigation of the heat tracing temperature was a sensing bulb that was not adequately attached to the piping. This was not a contributing factor to the temperature drop since the system had been functioning properly prior to the flushing of the system. The sensing bulb was reanchored and the Heat Tracing Periodic Test was performed on HT-6.

e7lt>6Ol02 8~000~5l 7li09 PDR (5)DOCH, PDR S

NRC Form 344 (9 53)

NRC Form 355A US. NUCLEAR REGULATORY COMMISSION (983!

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVED OM8 NO. 3150-OIOS EXPIRES: 8/31/88 FACILITY NAME III DOCKET NUMEER 12) LER NUMBER (51 PAGE 13)

YEAR aror. SEGVENTIAL v~.v~i REYrdraN NVMEER 'M.'VMEER Turkey Point Unit 4 o s o o o 251 87 0 2 4 0 0 p 2 " p 3 TEXT IIImoro s/rsso is rsr/v/rod, vss sdd/o'orrsl IVRC Form 36SA's/ nll EVENT At 1750, on October 8, 1987, with Unit 4 in Mode 1 at 100X power, the temperature for Heat Tracing Circuit Number 6 (HT-6) decreased below 145 degrees. This circuit is located on the crosstie piping and valves between the 4A and 4B Boric Acid pumps and on the pump s discharge line to the inlet of the Boric Acid Filter.

Preparations were made to shut down the unit as required by Technical Specification (TS) 3.0.1. Investigation for the cause of the temperature decrease revealed the event occurred during the time that the 4B Boric Acid pump crosstie line was being flushed to facilitate maintenance work on valve 4-374. During the flush the temper-ature decreased to 117 degrees. The flushing was stopped and the system was restored to the normal alignment. .At 1915, the temperature for HT-6 began increasing. The decision as made to postpone the load reduction for removing the unit from the line until 2130, which would leave sufficient time for an orderly shutdown. At 1930, a blended makeup flow was pumped through the normal boric acid flowpath to ensure the piping was not blocked by crystalized boric acid and to accelerate the rate of the temperature increase . The temperature increased steadily until was above 145 degrees at 2007 hours0.0232 days <br />0.558 hours <br />0.00332 weeks <br />7.636635e-4 months <br /> . This terminated the shutdown action requirement it for TS 3.0.1. Also found as a part of the investigation conducted when the heat tracing circuit temperature dropped was a temperature sensing bulb that was not adequately attached to the piping. This was determined not to have been a contrib-uting factor since the heat tracing circuit was functioning properly prior to the start of the flushing processing. The temperature sensing bulb was reanchored and the Heat Tracing Periodic Test was performed on HT-6.

CAUSE OF EVENT The event was caused by the cold flushing of the crosstie line . The temperature of the primary water which is used for flushing is relatively cold compared to the temperature of the borated water in the system. The temperature could not be maintained due to the heat being removed by the flush exceeding the heat input capacity of the heat tracing circuit.

ANALYSIS OP EVENT The boric acid flowpath was not blocked during the event and this was verified with the blended makeup to the Reactor Coolant System (RCS). Additionally, the boric acid flowpath from the Refueling Water Storage Tank (RWST) via the charging system to the RCS was operable at the time of the event. The capability to borate the RCS was not impacted by the event. Based on the above the health and safety of the public were not affected.

NRC FORM SddA 19S13I

NRC ForSr 344A U.S. NUCLEAR REOULATORY COMMISSION (Ml3)

LICENSEE EVENT REPORT ILER) TEXT CONTINU ION APPROVEO OMB NO. 319)WIOd EXPIRES: 8/31/88 FACILITY NAME (1) OOCKET NUMBER (1) I.ER NUMBER (4) PACE (3)

YEAR 54OUENTIAI NN REVI5K)N NUMSER NUM55R Turke Point Unit 4 o s o o o 2 5 1 8 7 0 2 4 0 0 3 OF 0 3 TEXT /// more dpeoe /I rer)rr/red, Iree edd dooe///RC Form 3SSA3/ (17)

CORRECTIVE ACTIONS

1) Preparations were made to shut down the unit when the heat tracing temperature decreased below 14S degrees, as required by TS 3.0.1.

2) The flushing of the 4B Boric Acid pump crosstie line was stopped and the normal system alignment was restored .

3) A blended makeup flow of borated water was pumped through the normal flowpath to ensure there was no blockage in the line, and to accelerate the rate of temperature increase in the line.

4) The temperature sensi.ng bulb was re-anchored to the boric acid pi.pe, and the Heat Traci.ng Periodic Test was performed on HT-6 to ensure the temperature controls were functioning properly.

.5) An evaluation will be made to determine if enhancements can be made to the flushing method, that would minimize the impact on the heat tracing temperature.

ADDITIONAL DETAILS Similar Occurrences: None.

NRC FORM 344A (983)

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P OX 14000, JUNO BEACH, PL 33408.0420 NOVEMBER 0 9 1987 L-87-453 IO CFR 50.73 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Gentlemen:

Re: Turkey Point Unit 4 Docket No. 50-251 Reportable Event: 87-24 Date of Event: October 8, l 987 Boric Acid Heat Tracing Circuit Number 6 Decreases to Less Than l45 De rees The attached Licensee Event Report is being submitted pursuant to the requirements of IO CFR 50.73 to provide notification of the subject event.

Very truly yours, C. O. Woody Group Vice President Nuc I ear Energy COW/PLP/gp Attachment cc: Dr. J. Nelson Grace, Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant SDF I /073/ I an FPL Group company

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