ML17264B011

LER 97-003-00:on 970730,high Steam Flow Bistable Instrument Setpoint Plus Instrument Uncertainty Could Exceed Allowable Value in ITS Was Identified.Caused by Entry Into ITS LCO 3.0.3.Switches Placed in Tripped configuration.W/970827 Ltr

ML17264B011
Person / Time
Site:	Ginna
Issue date:	08/27/1997
From:	Mecredy R, St Martin J ROCHESTER GAS & ELECTRIC CORP.
To:	Vissing G NRC (Affiliation Not Assigned), NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-97-003, LER-97-3, NUDOCS 9709040289
Download: ML17264B011 (7)

Text

CATEGORY REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9709040289 DOC.DATE: 97/08/27 NOTARIZED: NO DOCKET FACIL:50-244 Robert'Emmet Ginna Nuclear Plant, Unit 1, Rochester G 05000244 AUTH. NAME AUTHOR AFFILIATION ST MARTIN,J.T. Rochester Gas & Electric Corp.

MECREDY,R.C. Rochester Gas a Electric Corp.

RECIP.NAME RECIPIENT AFFILIATION VISSINGiG.S.

SUBJECT:

LER 97-003-00:on 970730,high steam flow bistable instrument setpoint plus instrument uncertainty could exceed "allowable value" in ITS was identified. Caused by entry into ITS LCO 3.0.3.Switches placed in tripped configuration.W/970827 ltr.

DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL SIZE:

TITLE: 50.73/50.9 Licensee Event Report (LER), Inciden Rpt, etc.

NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72). 05000244 0

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD1-1'D 1 1 VISSING,G. 1 1 INTERNAL: -~99/RAB 2 2 AEOD/SPD/RRAB 1 1 ILE CENTER 1 1 NRR/DE/ECGB 1 1 NRR/DEERE B 1 1 NRR/DE/EMEB 1 1 NRR/DRCH/HHFB 1 1 NRR/DRCH/HICB 1 1 NRR/DRCH/HOLB 1 1 NRR/DRCH/HQMB 1 1 NRR/DRPM/PECB 1 1 NRR/DSSA/SPLB 1 1 D

NRR/DSSA/SRXB 1 1 RES/DET/EIB 1 1 RGNl FILE Ol 1 1 EXTERNAL: L ST LOBBY WARD 1 1 LITCO BRYCE,J H 1 1 NOAC POOREgW 1 1 NOAC QUEENER,DS 1 1 NRC PDR 1 1 NUDOCS FULL TXT 1 1 NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD) ON EXTENSION 415-2083 FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 24 ENCL 24

AND ROCHESTER GAS AND EIECTRIC CORPORATION e 89 EAST AVENUE, ROCHESTER, N. Y, Id6d9 0001 ~'REA CODE 7I6 546.2700 ROBERT C. MECREDY Vice Pres:eeet i've'ecs ORe cecns August 27, 1997 U.S. Nuclear Regulatory Commission Document Control Desk Attn: Guy S. Vissing Project Directorate I-1 Washington, D.C. 20555

Subject:

LER 97-003, Bistable Instrument Setpoint (plus Instrument Uncertainty) Could Exceed Allowable Value, Causes a Condition Prohibited by Plant Technical Specifications R.E. Ginna Nuclear Power Plant Docket No. 50-244

Dear Mr. Vissing:

In accordance with 10 CFR 50.73, Licensee Event Report System, item (a) (2) (i) (B), which requires a report of, "Any operation or condition prohibited by the plant's Technical Specifications", the attached Licensee Event Report LER 97-003 is hereby submitted. A further assessment will be provided in a supplement to this LER which is expected to be submitted by September 29, 1997.

This event has in no way affected the public's h'ealth and safety.

Very truly yours, Robert C. Mecredy xc: Mr. Guy S. Vissing (Mail Stop 14B2)

PWR Project Directorate I-1 Washington, D.C. 20555 U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406 Ginna Senior Resident Inspector 9709040289 970827 Illlllilllllllllllllll PDR ADQCK 05000244 lliiiiliiilllllll!

PDR

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSIO APPROVED BY OMB NO. 31504)104 (4-95) EXPIRES 04/30/98 ESTIMATED BURDEN PER. RESPONSE To COMPLY WITH THIS MANDATORY INFORMATION COLLECTION REQUEST: 50.0 HRS.

LICENSEE EVENT REPORT (LER) REPORTED LESSONS LEARNED ARE INCORPORATED INTO THE LICENSING PROCESS AND FED BACK To INDUSTRY. FORWARD COMMENTS REGARDING BURDEN ESTIMATE To THE (See reverse for required number of INFORMATION AND RECORDS MANAGEMENT BRANCH IT.6 F33).

digits/characters for each block) U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555.0001, AND To THE PAPERWORK REDUCTION PROJECT FAGIUTY IIAME(t I DOCKET NUMBER (21 PAGE (3)

R.E. Ginna Nuclear Power Plant 05000244 1 OF4 Bistable Instrument Setpoint (plus Instrument Uncertainty) Could Exceed Allowable Value, Causes a Condition Prohibited by Plant Technical Specifications EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

SEQUENTIAL REVISION FACIUIY NAME DOCKETNVMEER MONTH DAY YEAR NUMBER NUMBER MONTH DAY YEAR FACIUTY NAME DOCKET NUMBER 07 30 97" 97 003 00 0B . 27 97 OPERATING THIS REPORT IS SUBMITTED PUR SUANT TO THE REQUIREMENTS OF 10 CFR 5: (Chock one or moro) (11)

MODE (9) 20.2201(b) 20.2203(a) (2) (v) 50. /3(a) (2) (i) 50.73(a) (2) (viii)

POWER 20.2203(a)(1) 20 2203(a)(3)(i) 50.73(a)(2)(ii) 50.73(a)(2)(x)

LEVEL (10) 100 20.2203(a) (2) (i) 20.2203(a)(3)(n) 50.73(a)(2)(iii) 73.71 20.2203(a) (2) (ii) 20.2203(a) (4) 50.73(a)(2)(iv) OTHER 20.2203(a) (2) (iii) 50.36(c)(1) 50.73(a) (2)(v) Specify in Abstract below or in NRC Foim 366A 20.2203(a)(2)(iv) 50.36(c)(2) 50.73(a)(2) (vii)

LICENSEE CONTACT FOR THIS LER (12)

NAME TE(EPHONE NVM8ER (Indude Area Code)

John T. St. Martin - Technical Assistant (716) 771-3641 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

REPORTABLE REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER CAUSE SYSTEM COMPONENT MANUFACTURER TO NPRDS TO NPRDS SUPPLEMENTAL REPORT EXPECTED (14) MONTH DAY YEAR EXPECTED YES SUBMISSION X (If yes, complete EXPECTED SUBMISSION DATE). NO DATE (15) 09 29 97 ABSTRACT (Limit to 1400 spacos, i.o., approximately 'I 5 single-spaced typewritten lines) (16)

On July 30, 1997, at approximately 1430 EDST, the plant was in Mode 1 at approximately 100% steady state reactor power. It was identified that the High Steam Flow Bistable Instrument Setpoint plus the Instrument Uncertainty could exceed the "Allowable Value" listed in the Ginna Station Improved Technical Specifications.

Immediate corrective action was to declare all four channels of High Steam Flow inoperable and enter Limiting Condition for Operation 3.0.3. When action was taken to place the affected bistable proving switches in the tripped position, the plant exited Limiting Condition for Operation 3.0.3.

The cause of this condition was insufficient margin between the High Steam Flow setpoint and the Allowable Value to account for process and instrument uncertainties.

Corrective action to prevent recurrence is outlined in Section V.B. Additional corrective actions will be identified in a supplement to this LER.

NRC FORM 366 (4-95)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION I4-95)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME I1) DOCKET LER NUMBER I6) PAGE I3)

YEAR SEQUENTIAL REVISION NUMBER NUMBER 2 OF 4 R.E. Ginna Nuclear Power Plant 05000244 97 003 00 II TEXT iifmore spece is required, use addi rionaf copies of NRC Form 366Ai (17)

PRE-EVENT PLANT CONDITIONS:

Personnel from Nuclear Engineering Services (NES) had been evaluating the impact of instrument uncertainties, including validation of actual plant-specific data.

j On July 30, 1997, at approximately 1430 EDST, the plant was in Mode 1 at approximately 100% steady state reactor power. In activities unrelated to plant conditions, NES personnel identified that the High Steam Flow Bistabie Instrument Setpoint, when added to the Instrument Uncertainty, could exceed the "Allowable Value" listed in the Ginna Station Improved Technical Specifications (ITS).

II. DESCRIPTION OF EVENT:

A. DATES AND APPROXIMATE TIMES OF MAJOR OCCURRENCES:

0 July 30, 1997, 1430 EDST: Event date and time.

July 30, 1997, 1430 EDST: Discovery date and time.

July 30, 1997, 1527 EDST: High Steam Flow Bistable proving switches are placed in the tripped position, thus restoring the channels to operable status.

EVENT:

On July 30, 1997, at approximately 1430 EDST, the plant was in Mode 1 at approximately 100%

steady state reacto'r power. In activities unrelated to plant conditions, NES personnel reported to Operations supervision that the High Steam Flow Bistable Instrument Setpoint, when added to the Instrument Uncertainty, could exceed the Allowable Value for this Engineered Safety Feature Actuation System (ESFAS) Instrumentation, as listed in ITS Table 3.3.2-1, Function 4.d.

Since the setpoint plus the uncertainty could be non-conservative with respect to the Allowable Value, all four channels of High Steam Flow were declared inoperable at approximately 1438 EDST. There is no ITS Limiting Condition for Operation (LCO) to address the condition of four channels inoperable, so ITS LCO 3.0.3 was entered.

The Plant Operations Review Committee (PORC) reviewed this condition and concurred with the recommendation to place the bistable proving switches for the affected bistables in the tripped position.

The Control Room operators placed the affected bistable proving switches in the tripped position.

This action ensured that any variation in the trip setpoint would not affect the completion of affected functions for High Steam Flow. Since the four affected channels of High Steam Flow were now performing their intended function by being maintained in the tripped configuration, these four channels were declared operable at approximately 1527 EDST on July 30, 1997.

NRC FORM 366A I4.95)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION f4.SSI LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) DOCKET LER NUMBER (6) PAGE (3)

YEAR SEQUENTIAL R NUMBER NUMBER 3 OF 4 R.E. Ginna Nuclear Power Plant 05000244 97 003 00 TEXT llfmoro spaceis required, use additional copies of NRC Form 366AI (17)

C. INOPERABLE STRUCTURES, COMPONENTS, OR SYSTEMS THATCONTRIBUTED TO THE EVENT:

None D. OTHER SYSTEMS OR SECONDARY FUNCTIONS AFFECTED:

None E. METHOD OF DISCOVERY:

This condition was selt-identified by an NES engineer while performing validation of calculated instrument uncertainties.

F. OPERATOR ACTION:

When notified of the results of the impact of the instrument uncertainty on operability of the High Steam Flow'Bistables, Operations supervision notified the Shift Supervisor of this condition.

Operations supervision also notified the NRC Resident Inspector.

Following notification, the Control Room operators declared all affected functions provided by the four channels of High Steam Flow inoperable and entered ITS LCO 3.0.3. After the affected bistable proving switches were placed in the tripped position and holds placed on these switches, they returned the four channels to operable status and exited ITS LCO 3.0.3.

G. SAFETY SYSTEM RESPONSES:

None III. CAUSE OF EVENT:

A. IMMEDIATECAUSE:

The immediate cause of the condition prohibited by Technical Specifications was entry into ITS LCO 3.0.3 due to four channels of High Steam Flow being declared inoperable.

B. INTERMEDIATE CAUSE:

The intermediate cause of all four channels of High Steam Flow being declared inoperable was a potential for instrument uncertainty to allow a trip setpoint to exceed the Allowable Value as listed in ITS Table 3.3.2-1 for ESFAS Instrumentation.

C. ROOT CAUSE:

The underlying cause of the potential to exceed the Allowable Value was that the existing margin between the High Steam Flow setpoint and the ITS Allowable Value is insufficient to account for process and instrument uncertainties.

NRC FORM 366A (4-95)

l NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION I4.85)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME I1) DOCKET LER NUMBER I6) PAGE I3)

YEAR SEQUENTIAL REVISION NUMBER NUMBER 4 OF 4 R.E. Ginna Nuclear Power Plant 05000244 97 003 00 TEXT (Ifmore space is required, use addi donal copies of NRC Form 366AI (17)

IV. ANALYSIS OF EVENT:

This event is reportable in accordance with 10 CFR 50.73, Licensee Event Report System, item (a) (2) {I)

{B), which requires a report of, "Any operation or condition prohibited by the plant's Technical Specifications." Having all four channels of High Steam Flow inoperable is a condition prohibited by the Ginna Station Improved Technical Specifications.

An assessment will be performed considering both the safety consequences and implications of this condition. A supplement to this LER will be submitted with the results of this assessment.

V. CORRECTIVE ACTION:

A. ACTION TAKEN TO RETURN AFFECTED SYSTEMS TO PRE-EVENT NORMAL STATUS:

The bistable proving switches were placed in the tripped configuration, and the affected functions for High Steam Flow were restored to operable status at approximately 1527 EDST on July 30, 1997.

B. ACTION TAKEN OR PLANNED TO PREVENT RECURRENCE:

The affected bistable proving switches are held in the tripped configuration. These switches will not be reset until completion of further evaluations.

o Additional corrective actions will be identified in a supplement to this LER.

VI. ADDITIONALINFORMATION:

A. FAILED COMPONENTS:

None B. PREVIOUS LERs ON SIMILAR EVENTS:

A similar LER event historical search was conducted with the following results: No documentation of similar LER events with the same root cause at Ginna Nuclear Power Station could be identified.

C. SPECIAL COMMENTS'one NRC FORM 366A (4-95)