ML18038B007

LER 94-009-00:on 940420,missed TS Surveillance Before Reactor Startup as Result of Misunderstanding of Ts.Util Will Submit TS Change to Clarify Frequency for IRM & APRM Instrumentation Funtional tests.W/941104 Ltr

ML18038B007
Person / Time
Site:	Browns Ferry
Issue date:	11/04/1994
From:	Hsieh C, Machon R TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-94-009-01, LER-94-9-1, NUDOCS 9411170027
Download: ML18038B007 (18)

Text

AWA~~J A A LACCELERATED RIDS PROCI'.SSli J.

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9411170027 DOC.DATE 94/11/04 NOTARIZED- NO DOCKET g FACIL:50-260 Browns Ferry Nuclear Power Station, Unit 2, Tennessee 05000260

,AUTH. NAME AUTHOR AFFILIATION HSIEH, C. S. Tennessee Valley Authority MACHON,R.D. Tennessee Valley Authority RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 94-009-00:on 940420,missed TS surveillance before reactor startup as result of misunderstanding of TS.Util wi.ll submit TS change to clarify frequency for IRM & APRM instrumentation funtional tests.W/941104 ltr.

DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR I ENCL ( SIZE:

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

NOTES RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-4-PD 1 1 WILLIAMS;J. 1 1 INTERNAL: ACRS 1 1 AEOD~OAB/cDS P 2 2 AEOD/SPD/RRAB 1 1 PILE CENTER+02 1' NRR/ DE/EE LB 1' RR~DE7EMEB 1 1 NRR/DORS/OEAB 1 1 NRR/DRCH/HHFB 1 1 NRR/DRCH/HICB 1 1 NRR/DRCH/HOLB 1 1 NRR/DRSS/PRPB 2 2 NRR/DSSA/SPLB 1 1 NRR/DSSA/SRXB 1 1 NRR/PMAS/IRCB-E 1 1 RES/DSIR/EIB 1 1 RGN2 .FILE 01 1 1 EXTERNAL: L ST LOBBY WARD 1 1 LITCO BRYCE,J H 2 2 NOAC MURPHY,G.A 1 1 NOAC POORE,W. 1 1 NRC PDR 1 1 NUDOCS FULL TXT 1 1 4OTE TO AL'L "RIDS" RECIPIENTS:

PLEASE HELP L'S TO REDUCE iVASTE! COiTAC'I"II IE DOCL ifEY,'I CONTROL DESk, ROONI Pl-37'(EXT. SR- 083 ) TO ELDflb:KTE 5'OL'R iAXIL PRO%I DISTRIBUTION LISTS.I OR DOCL'MEi'I'S 5'OL'Oi "I if I'.I)!

FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED'TTR 27 ENCL 27'

4l Tevessee Varey At.;rcpt ty. Pcs: 0",.ce Box 20CO, Decare;. A'acta 356G9 2OOO R. D; (Rick) Machon Vce Prescert. Bred".a Fe;p korea; Pact November 4, 1994 U.S. Nuclear Regulatory Commission 10 CFR 50.73 ATTN: Document Control Desk Washington, D.C. 20555

Dear Sir:

BROGANS FERRY NUCLEAR. PLANT (BFN) - UNITS 1q 2~ AND' - DOCKET NOS. 50-259I 50-260I AND 296 - FACILITY 'OPERATING LICENSE DPR-33'2'ND 68 LICENSEE EVENT REPORT 50-260/94009 The enclosed report provides details concerning a missed Technical Specification (TS) surveillance on the intermediate range monitors and average power range monitors. A surveillance was not performed on these monitors before startup on April 20, 1994 following a Unit 2 reactor trip.

This report is submitted in accordance with 10 CFR 50.73 (a)(2)(i')(B) as a condition prohibited by the plant's'S.

Section VII describes the commitment provided in this report.

R. D. M on Site Vice President Enclosure cc: See page 2

'008.5 9411170027 941104 PDR ADQCK 05000260 8 PDR

II U.,S. Nuclear Regulatory Commission Page 2 November 4, 1994 cc (Enclosure):

INPO Records Center Suite 1500 1100 Circle 75 Parkway Atl'anta, Georgi'a 30339 Paul Krippner American Nuclear Insurers Town Center, Suite 300S 29 South Main Street West Hartford, Connecticut 06107 NRC Resident Inspector Browns Ferry Nuclear Plant Route 12,,Box 637 Athens,. Alabama 35611 Regional Administrator U.S. Nuclear Regulatory Commission Region 101 II Marietta Street, NW,, Suite 2900 Atlanta, Georgia 30323 Mr. J. F. Williams, Project Manager U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852

II 41 f~r

NRC FORH 366 U.S. NUCLEAR REGULATORY 'C<NIIISSION APPROVED BY <WB NO. 3150-0104 (5-92) EXPIRES 5/31/95 ESTIHATED BURDEN PER RESPONSE TO COMPLY NITH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS ~

LICENSEE EVENT REPORT (LER) FORNARD COHMENTS REGARDING BURDEN ESTIHATE TO THE INFORMATION AND RECORDS MANAGEHENT BRANCH (HNBB 7714), U.S. NUCLEAR REGULATORY COHHISSION, (See reverse for required nunbcr of digits/characters for each block) NASHINGTON, DC 20555-0001 AND TO THE PAPERNORK REDUCTION PROJECT <3140-0104), OFFICE OF HANAGEHENT AND BUDGET MASHINGTON DC 20503.

FACILITY NAME (1) DOCKET NINIBER (2) PAGE (3)

Browns Ferr Nuclear Plant BFN Unit 2 05000260 1 OF 6 TITLE (4) Hissed Technical Specification (TS)Surveillance before Reactor Startup as a Result of a Hisunderstanding of TS EVENT DATE 5 LER NN<BER 6 REPORT DATE 7 OTHER FACILITIES INVOLVED 8 SEQUENTIAL REVISION FACILITY NAHE HA DOCKET NUHBER HONTH DAY YEAR YEAR HOHTH DAY YEAR NUHBER NUHBER FACILITY NAHE NA DOCKET NUHBER 20 94 94 009 00 11 04 OPERATING N

THIS REP<XIT IS SUBHITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR: Check one or more 11 H<SE (9) 20.402(b) 20.405(c) 50.73(a)(2)(iv) 73.71 (b)

PONER 20.405(5)(1)(i) 50.36<c)(1) 50.73(a)(2)(v) 73.71(c) 000 LEVEL (10) 20.405(a)(1)(ii) 50.36(c)(2) 50.73(a)(2)(vii) OTHER 20.405<a)(1)(iii) 50.73(a)(2)(i)(B) 50.73(a)(2)(viii)(A) (Specify in 20.405(a)(1)(iv) 50.73(a)(2)(ii) 50 '3(a)(2)(viii)(B) Abstract below and in Text, 20.405(a)(1)(v) 50 '3(a)(2)(iii) 50.73(a)(2)(x) NRC Form 366A LICENSEE CONTACT FOR THIS LER 12 NAHE TELEPHONE NUMBER (Include Area Code)

Clare S. Hsieh, Compliance Licensing Engineer (205) 729-2635 CNIPLETE ONE LINE FOR EACH C<NPONENT FAILURE DESCRIBED IN THIS REPORT 13 REPORTABLE REPORTABLE CAUSE SYSTEM COMPONENT HANUFACTURER CAUSE SYSTEH COMPONENT HANUFACTURER TO NPRDS TO NPRDS

~4i~ggg SUPPLEMENTAL REPORT EXPECTED 14 EXPECTED HONTH DAY YEAR YES SUBMISSION (If yes, complete EXPECTED SUBHISSION DATE).

X NO DATE (15)

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

On October 5, 1994, during a review of the plant's Technical Specification (TS) surveillances, TVA determined that the Intermediate Range Monitor (IRM) instrumentation functional test was not performed before the Unit 2 startup on April 20, 1994. Further review also determined that a similar test for the Average Power Range Monitors (APRMs) was not performed. This is a condition prohibited by the plant's TS requirements and is reportable per 10 CFR 50.73(a)(2)(i)(B). BFN TS requires that they be tested before each startup and once a week for IRMs during refueling and weekly for APRMs when required to be operable. The root cause of this event was a misunderstanding of TS resulting in inadequate procedures. The General Operating Instructions (GOIs) for Unit Startup did not require the IRMs and the APRMs to be functionally tested before each startup.

Additionally, the IRM functional test surveillance did not specify the correct frequency.

To prevent recurrence, the GOIs have been revised to require IRM and APRM tests be performed before each startup. 'The surveillance for the IRMs was also revised to require IRM testing before each startup. TVA will train licensed operators on this event. As an enhancement, TVA will submit a TS change to clarify the frequency for the IRM and APRM instrumentation functional tests.

NRC FORM 366A U.S. IN)CLEAR REGULATORY CQOIISSION APPROVED BY M8 NO. 3150-0104 (5-92) EXPIRES 5/31/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY IIITH THIS INFORMATION COLLECT IOM'EQUEST: 50.0 HRS FORNARD COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION AND RECORDS IIAMAGEHENT LICENSEE EVENT REPORT BRANCH (HNBB 7714), U.S. NUCLEAR REGULATORY COHHISSIOM, TEXT CONTZNUATZON 'WASHINGTON, DC 20555-0001, AND TO THE PAPERMORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT 'AND BUDGET, llASHING'TOH, DC 20503 FACILITY IUL% (1) DOCKET NINIBER (2) LER NQIBER (6) PAGE (3)

YEAR SEQUENT IAL REVISION NUMBER 'NUMBER Browne Ferry Unit 2 05000260 94 009 00 2 of 6 TEXT If more s ce is r uired use additional co ies of NRC Form 366A (17)

PLANT CONDITIONS At the time of this event, Unit 2'as starting up on April 20, 1994 following, the April 18, 1994 reactor trip. Units 1 and 3 were shutdown and defueled.

DESCRIPTION OP EVENT A. Event:

The NRC Senior Resident Inspector expressed a concern regarding the operability of the Intermediate Range Monitors (IRMs) [IG],

from a Technical Specification (TS) aspect, following the Unit 2 shutdown on October 1, 1994. In response to this concern, TVA conducted a review of the plant's TS surveillance requirements and functional tests performed during previous outages. It was during

.this review that on October 5, 1994, TVA determined the ZRM instrumentation functional test was not performed before the Unit 2 startup on April 20, 1994. Further review also determined that a similar functional test for the Average Power Range Monitors (APRMs) [IG) was not performed. The tests are required by TS to be performed once a week when in their operable mode and before each startup to verify the operability of the IRM and APRM functions in the neutron monitoring system.

TVA,performed the IRM and APRM functional tests after a Unit 2 reactor trip on April 15, 1994. However, when the reactor tripped again on April 18, 1994, the functional tests were not performed before the reactor restarted on April 20, 1994. BFN TS requires that IRMs and APRMs be tested before each startup. This is a condition prohibited'y the plant's TS and is reportable per 10 CFR 50.73(a)(2)(i)(B).

B. Ino erable Structures Com onents or S stems that Contributed to the Event:

None.

C. Dates and A roximate Times of Ma'or Occurrences:

April 15, 1994 'Unit 2 reactor scram occurred. Following the scram, APRM functional test was performed and APRMs were found to function properly.

April 16, 1994 IRM functional test was performed and'RMs were verified to be operable.

NRC FORH 366A U.S WCLEAR REGULATORY CQBII SSI ON APPROVED BY (WB NO. 3150-0104 (5-92) EXPIRES 5/31/95 ESTIHATED BURDEN PER RESPONSE TO COHPLY IJITH THIS IHFORHATION COLLECT ION REQUEST: 50.0 HRS ~ "FORMARD COMMENTS REGARDING BURDEN EST IHATE TO THE INFORHATIOH AND RECORDS HANAGEHEHT LICENSEE EVENT REPORT BRANCH (HNBB'714), U.S. NUCLEAR'EGULATORY COHHISSION, TEXT CONTINUATION MASHIHGTOH,, DC 20555-0001, AND TO THE PAPERMORK REDUCTION PROJECT (3150-0104), OFFICE OF HANAGEHEHT AND BUDGET, MASHIHGTOH DC 20503 FACILITY NAIK (1) DOCKET HIER (2) LER IRNBER (6) PAGE (3)

YEAR SEQUENTIAL REVISION NUHBER NUHBER Browns Ferry Unit 2 05000260 94 009 00 3 of 6 TEXT tf more s ce is r ired use additional co ies of NRC Form 366A (17)

April 17, 1994 Unit 2 was restarted.

April 18, 1994 Another Unit 2 reactor scram occurred.

April 20, 1994 Unit 2 was restarted. IRM and APRM functional tests were not performed pri'or to this startup.

October 1, 1994 Unit 2 shutdown for refueling outage.

October 4, 1994 IRM and APRM functional tests were performed satisfactory.

October 4-5, 1994 Responding to NRC's concern with the operability of the IRMs following shutdown, TVA conducted a review of TS re(Luirements and a historical research of surveillances performed during previous outages. On October 5, 1994, TVA determined that a missed IRM functional test occurred prior to Unit 2 startup on April 20, 1994. Further review also determined that the APRM functional test was not performed.

D. Other S stems or Seconda Functions Affected:

None.

E. Method of Discove As noted in the event description, TVA discovered this event during a review of TS surveillance requirements and functional tests performed during previous outages.

F. 0 erator Actionst None.

0. Safet S stem Res onses:

None.

0 l,

NRC FOHN 366A U.S. WCLEAR REGULATORY CQBIISSION APPROVED BY (NB NO. 3150-0104 (5-92) EXPIRES 5/31/95 ESTIHATED 'BURDEN PER RESPONSE TO COHPLY NITH THIS INFORHATIOH COLLECTION REOUEST: 50.0 HRS. FORIIARD COHNEHTS REGARDING BURDEN EST IHATE TO THE INFORHAT I OH AND RECORDS HANAGEHENI'RANCH LICENSEE EVENT REPORT (HNBB 7714), U.S. NUCLEAR REGULATORY COHNISSIOH, TEXT CONTINUATION NASHINGTON, DC 20555-0001, AND TO THE PAPERNORK REDUCTIOH PROJECT (3150-0104), OFFICE OF HANAGEHEHT AND BUDGET, NASNINGTOH DC 20503 FACILITY NAlK (1) DOCKET NN8ER (2) LER NQNER (6) PAGE (3)

YEAR SEQUENTIAL REVISION NUHBER NUNBER Browne Ferry Unit 2 05000260 94 009 00 4 of 6 TEXT tf more s ce is r ired use additional co ies of HRC Form 366A (17)

ZZI ~ CAUSE OF THE EVENT A. Immediate Causet None.

B. Root Causes The root cause of this event was a misunderstanding of the TS resulting in inadequate procedures. TS Table 4.1.A requires that the frequency for the IRM and APRM instrumentation functional tests be performed before each startup and once a week for IRMs during refueling and weekly for APRMs when required to be operable. However, the General Operating Instructions (GOZs) for Unit Startup did not require the IRM and APRM functional tests to be performed before each startup because it was believed that to meet the plant's TS requirements, the tests were only needed to be performed once every seven days. Additionally, the Surveillance Instruction (SI) for the IRM functional test did not specify the correct frequency.

C. Contributin Factors:

Since the APRM and IRM instrumentation functional tests were performed on April 15 and 16, 1994, respectively, they were considered to be within their seven-day periodicity. Thus, the tests were not performed again before the Unit 2 reactor startup on April 20', 1994 following the April 18, 1994 scram. However, this was not in strict compliance with the BFN TS.

IV. ANALYSIS OF THE EVENT At BFN, the IRMs are quality related instrumentation. No credit is taken for the ZRM high flux scram in any design basis event. The APRM high flux (less than or equal to 15 per cent of rated power) provides the safety related function. Eight IRMs are provided to monitor and record core neutron flux between the startup range and the power range during reactor startup and shutdown. Protective trips (Control Rod Blocks and SCRAMS) are initiated through instrument channels to protect against rapid increases in reactor power. Three IRMs per Reactor Protection System (RPS) channel are required to be operable by the TS. The APRMs, which utilize the inputs from the local power range monitors, determine the core bulk thermal flow, rod blocks, and scram trips. The APRMs provide outputs to the rod block monitor system, reactor control system, and RPS. The APRMs are required to be operable in all plant modes except shutdown.

Ik NRC FORH U S IRICLEAR REGULATORY'QI(ISSI(NI APPROVED BY (IGI NO. 3150-0104 366A'5-92)

EXPIRES 5/31/95 ESTIHATED BURDEN PER RESPONSE TO COHPLY WITH THIS INFORHATIOH COLLECTION REQUEST: 50.0 NRS. FOR'WARD COHHENTS REGARDING BURDEN ESTIHATE TO THE INFORHATION AND RECORDS HANAGEHENT LICENSEE EVENT REPORT BRANCH (HNBB 7714), U.ST NUCLEAR REGULATORY COHHISSION, TEXT CONTZNUATZON WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF HANAGEHENT AND BUDGET, WASHINGTON DC 20503 FACILITY NAHE (1) DOCKET NIMBER (2) LER NLIIBER (6) PAGE (3)

YEAR SEQUEHI'IAL REVI SIGH NUHBER NUHBER Browns Ferry Unit 2 05000260 94 009 00 5 of 6 TEXT tf more s ce is r ired use edditions( co ies of NRC Form 366A (17)

Since the APRMs and IRMs were verified to be operable on April 15 and 16, 1994, respectively, and verified again to be operable on October 4, 1994 following the October 1, 1994 shutdown, the RPS would have been able to respond properly, if needed, under the startup condition or at power. Therefore, the plant's safe shutdown capabilities were not diminished, and plant safety was not adversely affected.

V CORRECTIVE ACTIONS A. Immediate Corrective Actionsl None.

.B. Corrective Actions to Prevent Recurrence)

TVA has revised the GOIs for Unit Startup to require the IRM and APRM instrumentation (Control Rod Blocks/SCRAMS) be tested before each startup. The SZ for the IRM functional test was also revised to require IRMs testing before each startup. Additionally, TVA will train licensed operators on this event.

A review of other TS conditional procedures related to startup has not found any other GOIs and SIs for nuclear instrumentation with incorrect testing frecpency.

C. Other Actions As an enhancement, TVA will submit a TS change to clarify the frequency for the IRM and APRM instrumentation functional tests.

VI+ ADDITIONAL ZNFORMATION A. Failed Com onents(

None.

B. Previous LERs on Similar Events:

There were no previous LERs that were caused by missed neutron monitor surveillance functional tests due to inadecpxate procedures. However, there have been several previous LERs on missed surveillances as a result of personnel errors, ambiguous instructions, and inadequate control and tracking. The corrective actions on these LERs would not have precluded the event in this LER.

NRC. FORN 366A U.S. NUCLEAR REGULATORY CQBIISSION APPROVED BY (NB NO. 3150-0104 (5-92) EXPIRES 5/3'I/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS. FORllARD COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION AND RECORDS MANAGEMENT LICENSEE EVENT REPORT BRANCH (HMBB 7714) ~ U.S. NUCLEAR REGULATORY COMMISSION, TEXT 'CONTINUATION I!ASH INGTOM, DC 20555-0001, AND TO THE PAPERNORK REDUCTION PROJECT (3150-0104), OFF ICE OF MANAGEMENT AMD BUDGET, NASHINGTON DC 20503 FACILITY NAME (1) DOCKET IRNBER (2) LER IRHQER (6) PAGE (3)

YEAR SEQUENTIAL REVI SIGH NUMBER NUMBER Browne Ferry Unit 2 05000260 94 009 00 6 of 6 TEXT If more s ce is r ired use additionsl co ies of NRC Form 366A (17)

'VII. Commitment TVA will train licensed operators on this event before the startup from the Unit 2 Cycle 7 outage.

Energy Industry Identification System (EZIS) system and component codes are identified in the text with brackets (e.g., [XX].

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