ML18005A582

LER 88-023-00:on 880812,control Operator Observed Midposition Indication on Control Board for Gagged Open Porv,Resulting in Tech Spec Noncompliance.Caused by Isolation of Nitrogen/Air Supply to actuator.W/880908 Ltr

ML18005A582
Person / Time
Site:	Harris
Issue date:	09/08/1988
From:	Howe A, Watson R CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
HO-880186-(O), LER-88-023, LER-88-23, NUDOCS 8809140359
Download: ML18005A582 (6)

Text

AC CELE RAT@ NZNi5 DIRKROMQ~(RID@~~M ACCESSION NBR:8809140359 DOC.DATE: 88/09/08 NOTARIZED: NO, DOCKET FACIL:50-400 Shearon Harris Nuclear Power Plant, Unit 1, Carolina 05000400 AUTH. NAME AUTHOR AFFlLZATION HOWE,A.J. Carolina Power & Light Co.

WATSON,R.A. Carolina Power & Light Co.

RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 88-023-00:on 880812,reactor coolant sys vent opened less than required Tech Spec due to failure of. valve gagging.

W/8 ltr.

DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR i ENCL I SIZE:

TITLE: 50.73 Licensee Event Report (LER), Incident Rpt, etc.

NOTES:Application for permit renewal filed. 05000400 RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL h PD2-1 LA 1 1 PD2-1 PD ,1 1 BUCKLEYiB 1 1 INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 2 ACRS WYLIE 1 1 AEOD/DOA 1 1 AEOD/DSP/NAS 1 1 AEOD/DSP/ROAB 2 '2 AEOD/DSP/TPAB 1 1 ARM/DCTS/DAB 1 1 DEDRO 1 1 NRR/DEST/ADS 7E 1 0 NRR/DEST/CEB 8H 1 1 NRR/DEST/ESB 8D 1 1 NRR/DEST/ICSB 7 1 1 NRR/DEST/MEB 9H 1 1 NRR/DEST/MTB 9H 1 1 NRR/DEST/PSB 8D 1 1 NRR/DEST/RSB 8E 1 1 NRR/DEST/SGB 8D 1 1.

10 NRR/DLPQ/QAB 10 1 1 NRR/DLPQ/HFB NRR/DOEA/EAB NRR/DREP/RPB ll 10 1

1 2

1 1

2 NRR/DREP/RAB NRR/DRED/H IB 10 9A 1

1 1

1 NUDOCS-ABSTRACT 1 1 1 1 RES TELFORD,J 1 1 RES/DSIR DEPY 1 1 RES/DSIR/EIB 1 1 RGN2 FILE 01 1 1 EXTERNAL: EG&G WILLIAMSiS 4 4 FORD BLDG HOY,A 1 1 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC HARRIS,J 1 1 NSIC MAYS,G 1 1 S h

TOTAL NUMBER OF COPIES REQUIRED: LTTR 46 ENCL 45

NRC Form 355 U.S. NUCLEAR REOULATOAY COMMISSION (843)

APPROVED OMB NO. 3160410I EXPIRES: BI31I88 LICENSEE EVENT REPORT (LER)

FACILITY NAME (I)

SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1'OCKET 05000pp1OFp NUMBER l2) PA E 3I TECHNICAL SPECIFICATION NON-COMPLIANCE: REACTOR COOLANT SYSTEM VENT LESS THAN RE UIRED DUE TP FAILURE OF VALVE GAGGING DEVICE EVENT DATE (6) LER NUMBER (5) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

~+c'SEQUENTIAL REY~~ DAY YEAR FACILITYNAMES OOCKFT NVMBERIS)

MONTH DAY YEAR YEAR NUMBER NUMSER MONTH 0 5 0 0 0 0 8 12 88 8 0 2 3 ppp 9 0 8 8 0 5 0 0 0 THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR (): (Check one or morr of thr follovffnEI (11)

OPERATINO MODE (8) 20A02(b} 20A05(c) 50.73(e) l2) llv) 73.71(D)

POWER 20A05(e)(1)(0 50M(c)(I) 60.73(e)(2)(v) 73.71(c)

E,EVEL (10) 20A05(e)(1)(D) 60.38(c)(2) 60.73(e)(2) (vE) OTHER ISpeClfy In Ahrtrett Orlove end ln Text, HRC Form 20A05(e)(1)llil) 50.73(e)l2)(I) 60.73(e)(2)(vill)lA) 366AI

. 5.'R'4 20A05(e)II)(lv) 50.73(e)(2)DI) 50.73(e) (2)(vill)(8) 20A05( ~ )(1)lv) 50.7 3(e) (2) (lii) 50.73( ~ ) (2) le)

LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER AREA CODE ANDREW J. HOWE SR. ENGINEER 9 19 362 -2 719 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

CAUSE SYSTEM COMPONENT MANVFAC TUAER REPORTABLE TO NPADS re@

n~ '

$ <r CAUSE SYSTEM COMPO N E NT MANUFAC.

TVRER EPORTAB LE TO NPRDS N~(

FA%ÃlkYi fAN3(d(L}t SUPPLEMENTAL REPORT EXPECTED (IE) MONTH DAY YEAR EXPECTED SUBMISSION DATE (16)

YES Ilfyrr, complrre EXPECTED SVBkrISSIDH DATE/ NO ABSTRACT I(.lmlt ro rr00 rpecrr. I.e., epproxlmetely fifteen rlnolrrpece typrvrrlrtrn llnrd (15)

ABSTRACT:

On August 12, 1988, the plant was in Mode 5, 100'F, with the Reactor Coolant System (RCS) drained and vented through a gagged open pressurizer Power Operated Relief Valve (PORV) in compliance with Technical Specification 3.4.9.4 for low temperature overpressure protection. An operator observed a midposition indication on the control board for the gagged open PORV at 1515, and this was locally verified at 1540. Since it was unknown whether the midposition PORV provided the minimum 2.9 square inch vent path required by the Technical Specifications, the remaining two PORVs were returned to operational status and opened at 1620.

An cinitial evaluation of vent path opening available with a PORV at midposition yielded only a 1.25 square inch vent, and a total of only 1.47 square inches was determined to have existed when taking credit for all other openings in the RCS. Thus the requirements'f Specification 3.4.9.4 were not met.

Over time, the packing in the PORV was compressed .by the valve gag, allowing the valve to drift approximately 1/4 inch closed. A longer gagging device was installed on the PORV to ensure it remained fully open until two pressurizer safety relief valves could be removed to provide an RCS vent. A new device which will not be subject to this potential failure mechanism will be designed for the PORV prior to its next use as a vent. Additional procedural controls for the use of valve gags will be implemented to reduce the potential for i 88091~03m 88090e PDR RDOCK 05000400 NAC Form 358 S PNU, ln nv I

NRC Form 3SEA U.S, NUCLEAR REGULATORY COMMISSION (943(

LICENSEE EVENT REPORT (LERI TEXT CONTINUATION APPROVED OMB NO. 3(50M(0<

EXPIRES: 8/3l/88 FACILITYNAME (ll DOCKET NUMBER (ll LER NUMBER PSI PAGE (Sl SEQUENTIAL REVISION SHEARON HARRIS NUCLEAR POWER PLANT YEAR NVM ER NUMBER UNIT 1 0 5 0 0 0 OF TEXT ///more epeoe i /tu/I/e L uee ~ ///Or'M/ ///IC Form 355AB/ (Ill INITIAL CONDITIONS:

The plant was in Mode 5, 100'F, with the Reactor Coolant System (RCS) drained down to approximately four inches below the reactor vessel head flange and vented to the Pressurizer Relief Tank via a gagged open valve.

DESCRIPTION:

On August 1'2, 1988, at 1515, a control operator observed a midposition indication on valve 1RC-114, Pressurizer Power Operated Relief Valve (PORV)

(EIIS: AB:PCV). This valve had been previously opened and a gag device installed to ensure a minimum 2.9 square inch vent path for the RCS in compliance with Technical Specification 3.4.9.4, Low Temperature Overpressure Protection. The valve was locally checked and was verified to be approximately midposition at 1540.

Since it was not known whether the midposition PORV provided the minimum required 2.9 square inch vent, the remaining two PORVs were restored to operational status by re-establishing nitrogen to the valve operators, and the two PORVs were opened at 1620, ensuring compliance with Specification 3.4.9.4.

An initial evaluation of the midposition PORV configuration concluded that it had provided only a 1.25 square inch opening. The existing configuration of the RCS at that time also had two other openings, 3/8 inch pipes for the reactor vessel head vent and reactor vessel level indicator, for a cumulative vent path of 1.47 square inches. This was determined at 1745, and the Shift Foreman reported the situation to the NRC at 1900, as required by 10 CFR 50.72(b)(2)(iii). (Further evaluation based on the increased length of the longer gag subsequently installed on the PORV determined that the actual PORV position 'provided approximately 2 square inches of vent path.) r CAUSE:

The PORV uses a spring close, nitrogen/air open actuator. The .nitrogen/air supply to the actuator had been isolated for outage activities, and without this force acting against the spring, the valve packing was gradually compressed sufficiently to allow the PORV to move from the fully open posltlon ~

The gag was originally installed on the PORV under 'the control of a work request/authorization (WR&A) to support surveillance test activities.,

Although the WR&A provides the administrative control of the 'use of valve gags, no specific .procedure provides guidance on the acceptability of the design of such devices. It was not realized that slight valve movement could result in noncompliance with the Technical Specifications.

NRC FORM ESSA *U.S GPO:(988.0 82E 538/455 (9831

NRC Form 3ddA U.S. NUCLEAR REGULATORY COMMISSION (943)

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVEO OMB NO. 3)50-0(BE EXP)RES( 8/31/88 FACILITY NAME (II OOCKET NUMBER (2( LER NUMBER (6I pAGE (3)

SEOVENTIAL REVISION SHEARON HARRIS NUCLEAR POWER PLANT- YEAR NVMSER NVMSE/I IT 1 OF 0 5 0 0 0 TEXT /1/ more Eeece /r reEM)e/6 eoe ~ I////e/ HRC Form 355A'g/ (IT)

CAUSE: (continued)

There have been no previous similar events with failures of valve gags. A pressurizer PORV has been gagged open during previous outages without occurrence of failure. The packing on the PORV had been recently replaced and the compressibility of new packing material contributed to the event. In addition, in previous situations with the PORVs gagged, the nitrogen/air supply was not isolated, so that this was the first time the gagging device alone was holding the valve open against the spring.

ANALYSIS:

Technical Specification 3.4.9.4 requires either two OPERABLE PORVs of the Low Temperature Overpressure Protection System, or a minimum 2.9 square inch vent, which corresponds to the area provided by a single PORV in the fully open position. This ensures protection of the RCS against the overpressure transient associated with either 1) the start of an idle Reactor Coolant Pump (RCP) with secondary side of the steam generators less than 50'F above primary coolant temperature, or 2) the start of an idle charging/safety injection pump (CSIP) and injection into a water-solid RCS. These transients are associated with the 10CFR 50 Appendix G limits based on protecting the reactor vessel integrity, assuming a vessel metal irradiation at 4 Effective Full Power Years (EFPY).

With the RCS drained and vented, the RCPs could not be started'ithout violating several prerequisites for pump start. In fact, the RCP breakers were not in service, greatly reducing any potential for inadvertent start-up due to personnel error. One CSIP was in operation during the event, with the

'ther available pump breaker, racked out as required by Technical Specifications below 335'F.

During this event, a 1.47 square inch vent was calculated to be available to relieve any pressure transient, based on the PORV being at midposition.

Additional data obtained shows that the PORV had slipped approximately 1/4 inch from the fully open position, and this wo'uld indicate that up to 2 square inches of vent path actually existed.

Since a substantial vent path actually existed, and with the RCPs out of service and the RCS not water-solid, and with vessel irradiation levels not yet at the limiting value of 4 EFPY, the probability 'of a limiting pressure transient is not likely. The required vent .path was unavailable for at least one hour and five minutes, based on the time of discovery until correction.

This event is reportable in accordance with 10 CFR 50.73(a)(2)(v) as a condition- that could have prevented the plant from being maintained in a safe shutdown condition due to an equipment failure.

'RC FORM SSSA RU.S GPO,(985.0.52d 538/E55 (983)

0 NRC Form 388A U,S. NUCLEAR RECULATORY COMMISSION (983 l LICENSEE EVENT REPORT {LER) TEXT CONTINUATION APPROYEO OMS NO. 3(50&104 EXPIRES; 8/31/88 FACILITY NAME (11 OOCKET NUMBER (2l LER NUMSER (Sl PACE (31

.ao, SEQUENT/AL P(j'( REV/SION SHEARON HARRIS NUCLEAR POWER. PLANT YEAR PL NUMOSR NUMOSR UNIT 1 OF 0 5 0 0 0 8 8 TEXT IIImoro sosso is /sr(son/, rrss 8//OOP8/ HRC form 3///IA's/((Tl CORRECTIVE ACTION:

1. The PORV packing was tightened and a longer gagging device was installed until two of the three pressurizer safety relief valves were removed to provide the required RCS vent.

2. A different device will be designed for installation on the pressurizer PORV which does not risk compression of the valve packing and closure of the valve. This new design will be in place prior to using an open PORV to comply with Specification 3.4.9.4

3. A procedure to control the use of valve gagging devices will be implemented, requiring such devices to be either vendor supplied or designed as a plant modification with appropriate engineering reviews and controls.

NRC FORM 388A *U.S.GPO;1988 0 824 538/455 19831

Carolina Power & Light Company HARRIS NUCLEAR PROJECT P.O. Box 165 New Hill, NC 27562 SEP 0 Sm80 File Number'SHF/10-13510C Letter Number'. HO-880186 (0)

U.S. Nuclear Regulatory Commission ATTN: NRC Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO. 50-400 LICENSE NO. NPF-63 LICENSEE EVENT REPORT 88-023-00 Gentlemen.'n accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. This report fulfills the requirement for a written report within thirty (30) days of a reportable occurrence and is in accordance with the format set forth in NUREG-1022, September 1983.

Very truly yours, R. A. Watson Vice President Harris Nuclear Project RAW:tbb Enclosure cc'Dr. J. Nelson Grace (NRC RII)

Mr. B. Buckley (NRR)

Mr. W. H. Bradford (NRC SHNPP)

Zp MEM/LER-88-023/1/Osl