ML17264B129

LER 97-006-00:on 971103,NIS Audible Count Rate Function Was Inoperable.Caused by Misinterpretation of Event Sequence Due to Not Verifying Boron Concentration.B Verification Occurred Every 12 H Per ITS LCO Action 3.9.2.C.3.W/971203 Ltr

ML17264B129
Person / Time
Site:	Ginna
Issue date:	12/03/1997
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-97-006, LER-97-6, NUDOCS 9712100274
Download: ML17264B129 (13)

Text

CATEGORY 1 REGUZATO ZNFORNATZON DZSTR1BUT1ON ISTEN (RZDS)

ACCESSION NBR:9712100274 .DOC'.DATE:"97/12'/03 NOTARIZED: NO DOCKET 4 FACZZ:50-244 Robert 2Znaet Ginna Nuclear Plant, Unit 1, Rochester G 05000244 AUTH.NAME ' 'UTHOR AFFILIATION ST.MARTIN,J.T. Rochester Gas & Electric Corp.

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

RECIP.NAME RECIPIENT AFFILIATION VISSING, G. S'.,"-;

SUBJECT:

LER 97-006;-00:on!'971103,NIS audible count rate function was inoperable. Caused by misinterpretation of event secpxence due to not verify3ng boron concentration.B verification .occurred every 12 h- per ITS LCO acti. on 3.9.2.C.3.W/971203 ltr.

0 DISTRIBUTION:CODE: IE22T 'OPIES RECEIVED:LTR"J ENCL l" SIZE:

TITLE: '50.73/50.9 Li.censee Event Report (LER), Incident Rpt', etc.

~ '\ I 4 1 NOTES:License Exp date in accordance wi.th 10CFR2,2.109(9/19/72). 05000244 G RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID '.CODE/NAME LTTR ENCL, R PD1-1 PD 1 1 VISSING,G. 1 1 INTERNAL: AEO 2 2 AEOD/SPD/RRAB 1 1 E CENTE 1 1 NRR/DE/ECGB 1 1 NRR DE E LB 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 NRR/DSSA/SRXB 1 1 RES/DET/EIB '1 1 RGN1 FILE 01 1 1 D

EXTERNAL: L ST LOBBY WARD 1 1 LITCO BRYCE,J H 1 0

1 NOAC POORE,W. 1 1 NOAC QUEENER,DS 1 1 NRC PDR 1 1 NUDOCS FULL TXT 1 1 U

NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRZBUTION 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 ElECTRIC CORPORATTON ~ 89 EASTAVENUE, ROCHESTER, M Y. l4649-D001 AREA CODE7I6 546-270D ROBERT C. MECREDY Vice President Nuctear operations December 3, 1997 U.S. Nuclear Regulatory Commission Document Control Desk Attn: Guy S. Vissing Project Directorate I-1 Washington, D.C. 20555

)

Subject LER 97-006, Verification of Boron Concentration Not Performed Due to Misinterpretation of Event Sequence, Resulted in Condition Prohibited by 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 97-006 is hereby submitted.

This event has in no way affected the public's health 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

"(- lllllllllllllllllllllllllllllllllllfllll a I 0 9'712i00274 'st7i20S PDR ADOCK 05000244 8 PDR

NRC FORM 366 U.S. N R REGULATORY COMNIISSIO AP ED BY OMB NO. 3150%104 (4-95) EXPIRES 04/30/98 ESTIMATED BURDEN PER RESPONSE To COMPLY WITH THIS MANDATORY INFORMATION COLLECTION REQUEST: 50.0 HRS.

LXCENSEE EVENT n REPORT,(LER) REPORTED LESSONS LEARNED ARE INCORPORATED INTO THE LICENSING PROCESS AND FED BACK To INDUSTRY. FORWARD (See reverse for required number'f COMMENTS REGARDING BURDEN ESTIMATE To THE 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 FACIUTY NAME Ill DOCKET irVMSER f2) PAD E I3I R.E. Ginna Nuclear Power Plant 05000244 1 OF 6 TrrLE fa)

Verification of Bof'on Concentration Not Performed Due to Misinterpretation of Event Sequence, Resulted in Condition Prohibited by Technical Specifications EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

SEQ ENTIAL REVISO FACILITYNAME DOCKET NUMBER MONlH DAY YEAR YEAR NUMBER MO DAY I:YEAR.

NUMBER

~ I FACIUTY NAME 03 97 97 006 00 1'2. 03 97 DOCKET NUMBER OPERATING THIS REPORT IS SUBMITTED PUBS UANT TO THE REQUIREMENTS OF 10 CFR E: (Check one or Illore) (1 1)

MODE (9) 20.2201(b) 20.2203(a) (2)(v) 50.73(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) 000 20.2203(a) (2) (i) 20.2203(a) (3)(ii) 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 Form 366A 20.2203(a)(2)(lv) . 50.36(c) (2) 50.73(a) (2)(vii)

LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE kUMBER Bncrude Area Code)

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

CAUSE SYSTEM COMPONENT REPORTABLE REPORTABLE MANUFACTURER CAUSE SYSTEM COMPONENT MANUFACTURER TO NPRDS To NPRDS SUPPLEMENTAL REPORT EXPECTED (14) MONTH DAY YEAR EXPECTED YES SUBMISSION (If yes, complete EXPECTED SUBMISSION DATE). X NO DATE (15)

ABSTRACT (Limit to 1400 spaces, I.e., approximately 15 single-spaced typewritten lines) (16)

On November 3, 1997, at approximately 1708 EST, the plant was in Mode 6, and refueling activities had been completed two days earlier. The reactor coolant system being maintained at a temperature of 75 degrees F, and the reactor cavity filled to greater than 23 feet. It was discovered that the nuclear instrumentation system audible count rate function was inoperable.

Immediate action was to ensure future compliance to the Ginna Technical Specifications for loss of this function.

This included verifying that the most recent boron concentration was within specified limits and formally tracking the time for future verification of boron concentration.

Due to a misinterpretation of the event sequence, the v'erification of boron concentration may not have been performed within the time period specified by Ginna Technical Specifications Required Actions for the most limiting event sequence.

Corrective action to prevent recurrence is outlined in Section V.B.

NRC FORM 366 (4-95)

I NRC FORM 366A . NUCLEAR REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER)

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

YEAR SEQUENTIAL REVISION NUMBER NUMBER R.E. Ginna Nuclear Power Plant 2 OF 6 05000244 97 006 00 TEXT (Ifmore spaceis required, use additional copies of NRC Form 366A/ (17)

PRE-EVENT PLANT CONDITIONS: < ~ ~

. ~ '

C ~ i l ~

lil ~

On November 3, 1997, the plant was in Mode 6 with the reactor coolant system (RCS) being maintained at a temperature of approximately.75 degrees F, and the reactor, cavity filled to greater than 23 feet. The plant was shut down for'refueling, and refueling activities (core alterations) had already been completed two days earlier, At approximately 0753 EST, the nuclear instrumentation system (NIS) Comparator and Rate drawer was removed from service for calibration per procedure CPI-COMP/RATE-N46/37 (Calibration of Comparator and Rate Drawer N46/37). At this time, the audible count rate function was operable.

DESCRIPTION OF EVENT:

DATES AND APPROXIMATE TIMES OF MAJOR OCCURRENCES:

November 3, 1997, 0025 EST: RCS boron concentration verified at 2463 PPM.

November 3, 1997, 0753 EST: NIS Comparator and Rate drawer is removed from service.

November 3, 1997, 1300 EST: RCS boron concentration verified at 2453 PPM.

November 3, 1997: Event date.

November 3, 1997, 1708 EST: Discovery date and time.

November 4, 1997, 0100 EST: RCS boron concentration verified at 2470 PPM.

November 4, 1997: NIS audible count rate is restored to operable status.

B. EVENT:

At the beginning of the afternoon shift on November 3, the operability of the NIS audible count rate function was questioned, since the normal audible beeping did not seem to be occurring. At this time, it was assumed that the audible count rate function had been made inoperable at the time procedure CPI-COMP/RATE-N46/37 was initiated. For convenience, this time was documented as the time administrative tracking had been initiated for the Comparator and Rate Drawer, at approximately 0753 EST on November 3. Therefore, using this event sequence and the assumed time of inoperability, the initial administrative tracking (which did not address the loss of audible count rate function) was supplemented by administrative procedure A-52.4 (Control of Limiting Conditions for Operating Equipment) at approximately 1708 EST. The A-52.4 tracking was initiated effective at 0753 EST as a "late entry".

NRC FORM 366A (4-95)

t NRC FORM 36BA . NUCLEAR 'REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER)

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

YEAR SEQUENTIAL REVISION NUMBER NUMBER R.E. Ginna Nuclear Power Plant 05000244 3 OF 6 97 006 00 TEXT ilfmore speceis required, use edditionel copies of NRC Form 368AJ (17)

Based on the event sequence that inoperability occurred at 0753 EST, the Control Room operators concluded that the plant continued to be in compliance with'Ginna Improved Technical Specifications (ITS) Limiting Condition for Operation (LCO) REQUIRED ACTIONS 3.9.2.C.1 and 3.9.2.C.2, since, there had been no core alterations or positive reactivity additions during this. time.

However, REQUIRED ACTION-3.9.2.C.3, for'RCS boron concentration verified to be within the limits specified in the Core Operating Limits Report (COLR), had only been accomplished at approximately 0025 EST and 1300 EST on November 3.

~ i. Xl Thus, at approximately 1708 EST on November 3, it was discovered that the NIS audible count rate was inoperable. 'Due to the assumed event sequence, it was concluded that inoperability occurred at 0753 EST, and the Control Room operators immediately entered ITS LCO 3.9.2 at, 1708 EST. The RCS boron concentration had been verified at approximately 1300 EST. Since the operators concluded that RCS boron concentration had not been verified within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of the assumed time of inoperability, the 1300 EST boron concentration was used to initiate the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> time requirement of ITS LCO REQUIRED ACTION,3.9.2.C.3. Subsequent RCS boron concentration verification would be required every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The next RCS boron concentration verification was performed at approximately 0100 EST, on November 4, and the NIS audible count rate function was restored to operable status later that morning.

Upon further review, activities performed per procedure CPI-COMP/RATE-N46/37 did not render the NIS audible count rate inoperable. Therefore, the event sequence concluding that inoperability occurred at 0753 EST is incorrect. The precise time that the NIS audible count rate function became inoperable on November 3 is not known, but the most limiting event sequence is if it occurred after 1300 EST, or between 0753 and 0900 EST. In either of these scenarios, ITS LCO REQUIRED ACTION 3.9.2.C.3 was not performed within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of the event.

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

None D. OTHER SYSTEMS OR SECONDARY FUNCTIONS AFFECTED:

None E. METHOD OF DISCOVERY:

This event was indicated during routine operations review of plant status during a shift turnover meeting, and was formally discovered shortly after shift turnover. However, the actual event sequence, including the fact that the precise time of inoperability is not known, was not discovered until several days later.

NRC FORM 366A (4-95)

NRC FORM 366A . NUCLEAR REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER)

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

YEAR SEQUENTIAL REVISION NUMBER NUMBER R.E. Ginna Nuclear Power Plant . 05000244 4 OF 6 97 006 00 TEXT Iifmore speceis required, use eddirional copies of NRC Form 366AJ (17)

F. OPERATOR ACTION:

The Control Room bperators'identified that there was no administrative tracking of the audible count. rate function, and submitted administrative procedure A-52.4 for formal tracking of the

~

audible'count.rate function. Based on their assumed event sequence, ITS LCO REQUIRED ACTION

~

3.9.2.C.3 had not been performed within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of inoperability, but a subsequent (1300 EST) boron concentration verification was used to initiate the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> time requirement. Future RCS boron concentration verification would be performed every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, per this REQUIRED ACTION.

The Control Room operators notified higher supervision.

V a ~" >,'} 1<

A Control Room operator manually restored the NIS audible count rate function during the midnight shift on November 4, 1997.

G. SAFETY SYSTEM RESPONSES:

None III. CAUSE'OF EVENT:

A. IMMEDIATECAUSE; The immediate cause of the condition prohibited by Technical Specifications was not verifying RCS boron concentration within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after discovering that the audible count rate function was inoperable, using the most limiting event sequence for loss of this function.

B. INTERMEDIATE CAUSE:

The intermediate cause of not verifying boron concentration was a misinterpretation of the event sequence.

ROOT CAUSE:

The misinterpretation of the event sequence led to a decision that was incorrect. Note that the precise time that the NIS audible count rate function became inoperable is not known.

This misinterpretation was made possible because there is no positive indication of when the audible count rate function became inoperable. Procedures were deficient in that the applicability of ITS LCO 3,9.2 at all times while in Mode 6 was not addressed in plant operating procedures.

Procedures were also deficient in that actions needed to verify the operability of the NIS audible count rate were not specified in calibration and test procedures.

NAC FOAM 366A (4-95)

NRC FORM 366A . NUCLEAR REGULATORY COMMISSION (4-95)

LXCENSEE EVENT REPORT (LER)

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

YEAR SEQUENTIAL REVISION NUMBER NUMBER R.E. Ginna Nuclear Power Plant 05000244 5 OF 6 97 006 00 TEXT llfmore spaceis required, use additional copies of NRC Form 366A/ (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

'pecifications": With the NIS audible count rate inoperable, not verifying RCS boron concentration within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after discovery. is not permitted by ITS LCO REQUIRED ACTION 3.9.2.C.3.

An assessment'was performed considering both the safety consequences and implications of this event with the following results and conclusions:

I I' 1" ~ Ili + ~

were no operational or safety consequences or implications. attributed to the delayed I'here verification of boron concengration because:

\

~ No core alterations and no positive reactivity additions occurred during this time period.

~ RCS boron concentration verification was being performed every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. Previous RCS boron samples had confirmed consistent boron concentrations that were well within the limit specified in the COLR.

Based on the above, it can be concluded that the public's health and safety was assured at all times.

CORRECTIVE ACTION:

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

~ The most recent RCS boron concentration was verified to be within the limit specified in the, COLR.

~ Subsequent boron verification occurred every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, as per ITS LCO Required Action 3.9.2.C.3.

~ After investigation of the cause for loss of this function, the audible count rate function was restored to operable status.

B. ACTION TAKEN OR PLANNED TO PREVENT RECURRENCE:

~ The requirement to have audible count rate operable at all times while in Mode 6 appears to be conservative. The High Flux at Shutdown alarm may provide adequate assurance of no adverse changes in core reactivity while in Mode 6 (and no core alterations or positive reactivity additions are occurring). Nuclear Safety and Licensing will be requested to evaluate a License Amendment to change this requirement in ITS.

NRC FORM 366A (4-95)

NRC FORM 366A . NUCLEAR REGULATORY COMMISSION (4.95)

LXCENSEE EVENT REPORT (LER)

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

YEAR SEQUENTIAL REVISION NUMBER NUMBER R.E. Ginna Nuclear Power Plant 05000244 6 OF 6 TEXT iifmore spaceis required, use additional copies of NRC Form 366A j (17)

Appropriate calibration and test procedures will be reviewed, and changed as necessary, to ensure audible count rate operability after completion of calibrations or tests.

Operating procedures will be reviewed, and changed as necessary, to ensure audible count rate operability is verifi6d when..in Mode 6.

( ~ ~ ',d Vl ~ ADDITIONALINFORMATION: ~ ~

II 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 Station could be identified.

C. SPECIAL COMMENTS:

None NRC FORM 366A (4-95)

0 I