ML18038B970

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LER 97-004-00:on 970909,TS Surveillances Were Not Performed During Refueling Outage Timeframe.Caused by Personnel Error. Incorporated Missed Snubber & Vacuum Breaker Surveillances Into Refueling Outage Schedule
ML18038B970
Person / Time
Site: Browns Ferry Tennessee Valley Authority icon.png
Issue date: 10/09/1997
From: Jay Wallace
TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML18038B969 List:
References
LER-97-004-03, LER-97-4-3, NUDOCS 9710210042
Download: ML18038B970 (12)


Text

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB No. 3150-0104 (4-95) EXPIRES 04/30/SB ESTIMATED BURDEN PER RESPONSE To COMPLY WITH THIS MANDATORY INFORMATION COLLECTION REQUEST: 50.0 LICENSEE EVENT REPORT (LER) HRS. REPORTED LESSONS LEARNED ARE INCORPORATED INTO THE LICENSING PROCESS AND FED BACK TO INDUSZTLY. FORWARD COMMENTS REGARDING BURDEN (See reverse for required number of ESTIMATE TO THE INFORMATION AND RECORDS digits/characters for each block) MANAGEMENT BRANCH IT e F33), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, OC 20555 FACIUTY NAME f11 DOCKET NIBNBtn tsl PAOE I3)

Browns Ferry Nuclear Plant (BFN) Unit 2 05000260 1 OF6 TITLE Ial Technical Specification ITS) surveillances were not performed during refueling outage timeframes. The root cause was a result of personnel error and not following procedure. This condition is prohibited by technical specifications.

EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACIUTIES INVOLVED (6)

FACIUTY NAME DOCKET SEQUENTIAL REVISION MONTH DAY .YEAR MONTH OAY YEAR NUMBER NUMBER BFN Unit 3 0500029 FACIUTY NAME DOCKET 09 09 97 97 004 00 10 09 , 97 NIA OPERATING THIS REPORT IS SUBMITTED PURSU ANT To THE REQUIREMENTS OF 10 CFR 5: (Check one or more) (11)

MODE (9) N 20.2201(b) 20.2203(a) (2) (v) X 50.73(a)(2)(I)(B) 50.73(a 20.2203(a) (1) 20. 2203 (a) (3) (I) 50.73 (a) (2) (ii) 50.73(a POWER LEVEL (10) 95 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 20.2203(a) (2)(iv) 50.36(c)(2) 50.73(a) (2) (vii) below or In LICENSEE CONTACT FOR THIS LER (12)

TELEPHONE NVMBEIISnerude Area Codel James E. Wallace, Licensing Engineer (205) 729-7874 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

REPORTABLE REPORTABLE CAUSE SYSTEM COMPONENT CAUSE SYSTEM COMPONENT TO NPRDS TO NPROS SUPPLEMENTAL REPORT EXPECTED (14) MONTH DAY YEAR EXPECTED YES SUBMISSION X No DATE (15)

(If yes, complete EXPECTED SUBMISSION DATE).

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

On September 9, 1997, at 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br />, Units 2 and 3 were approximately 100 and 95 percent power, respectively.

Unit 1 was defueled. At that time, TVA determined that previous testing of snubbers had not been performed during refueling outage timeframes in accordance with Technical Specification (TS) requirements. On September 19, 1997, TVA identified another similar occurrence regarding testing of the suppression chamber to reactor building vacuum breakers. These vacuum breakers were also not being tested during refueling outage timeframes.

These surveiliances were being performed as pre-outage or routine activities. The root cause for not performing the TS surveillances within the correct timeframe was the ineffective control of outage schedules. Specifically, Work Control (WC) personnel were not properly instructed to ensure that TS surveillances were incorporated in refueling outage schedules. Additionally, a procedure was not followed in that a special surveillance schedule was not provided for ail tests required to be completed during in refueling outages. The immediate corrective actions included placing these TS surveiliances into the refueling outage schedules. Corrective action to preclude recurrence was a review of TS surveillances to ensure no other surveillances were missed'being incorporated into refueling outage schedules. TVA will also provide guidance on job performance standards to WC personnel. This report is submitted in accordance with 10 CFR 50.73 (a)(2)(i)(B) as any operation or condition prohibited by the plant's technical specifications. No previous LERs were identified where TS surveillances were not incorporated into an outage schedule.

'i)7i02i0042 97iOOTI PDR ADQCK 05000260 S PDR

Ik NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (4 95L LICENSEE EVENT REPORT (LZR)

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

IA I I NUMBER NUMBER Browns Ferry Unit 2 05000260 2 of 6 97 -- 004 -- 00 hldfd dpdCO Id fdqUIld ~ Udd d hldhd Cdpldd O PLANT CONDITIONS At the time of the discovery of the condition, Unit 2 and Unit 3 were approximately 100 and 95 percent power, respectively. Unit 1 was shutdown and defueled.

DESCRIPTION OF EVENT A. Event NRC had questioned whether recent testing of snubbers in the standby liquid control system (SLCS) [BR) while the unit was at power was in conformance with Technical Specification (TS) requirements. On September 9, 1997, at 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br />, TVA's review determined that previous testing of snubbers had not been in compliance with the TS requirements.

SNUBBER EVENT Specifically, TS surveillance requirement 4.6.H.4 states: "during each refueling outage, a representati.ve sample of 10 percent of the total of each type of safety-related snubbers in'se in the plant shall be functionally tested either in place or in a bench test."

Refueling outage is defined as "the period of time between the shutdown of the unit prior to a refueling and the startup of the unit after that refueling." However, the snubber survei.llances were scheduled and performed based on a time interval (18 months).

Consequently, some of the snubber surveillances were not performed, during a refueling outage as defined by TS.

,Guidance given to Work Control personnel (utility, licensed) did not explicitly address the need to review TS to assure that TS surveillances were also incorporated into the refueling outage schedule. Therefore, the snubber TS surveillance was not added to refueling outage schedules. Additionally, Site Standard Practi.ce (SSP)-8.2, Surveillance Testing Program, Secti.on 3.4.3.D states, in part, a special surveillance schedule will be provided for all tests required to be completed during refueling outages. The snubber testing was not included in this schedule.

This snubber scheduling condition existed for Unit 2 since the Unit 2, cycle 8 outage (March 23, 1996), during the Unit 3, cycle 7 outage (February 22, 1997), until the Unit 2, cycle 9 outage, when the snubber TS surveillances were incorporated into the refueling outage schedules on September 11, 1997.

NRC FORM 366A (4-95l

NRC FORM 366A. U.S. NUCLEAR RMULATORYCOMMISSION

{4-96)

LICENSEE'VENT REPORT (LER)

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

A SQUNIAL IS ION NUMBER NUMBER Browns Ferry Unit 2 05000260 3 of 6 97 -- 004 -- 00 more specs rs reqirire . use e mons copies o 0 fnl VACUUM BREAKER On September 19, 1997, another similar occurrence was identified during the review of a scheduled ASME,Section XI quarterly surveillance. Specifically, during the review of a request to perform Unit 2 suppression chamber to reactor building [BF] [NG) vacuum breaker [VACB) cycling while the plant was at power, a

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conflict was identified with TS 4.7.A.3.b. This TS requires that:

"a visual examination and determination that the force required to open each vacuum breaker (check valve) does not exceed 0.5 psid will be made each refueling outage."

TVA reviewed past performances of the vacuum breaker surveillances, and the review revealed that these surveillances had been performed as ASME,Section XI tests on a quarterly basis but had not been performed during some refueling outages. As with the snubber event discussed 'above, SSP-8.2, Section 3.4.3.D, was not followed.

This vacuum breaker scheduling condition existed for Unit 2 since the Unit 2,,cycle 7 outage (October 1, 1994), during the Unit 3, cycle 7 outage (February 22, 1997), until the Unit 2, cycle 9 outage, when the vacuum breaker TS surveillances were 'incorporated into the refueling outage schedules on September 19, 1997.

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

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

None.

C. Dates and A roximate. Times of Ma'or Occurrencess September 9, 1997 at 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br /> CDT NRC had questioned whether recent testing of snubbers in the standby liquid control system while the unit was at power was in conformance with Technical Specification (TS) requirements. At this time, TVA's review determined that previous testing of snubbers had not been in compliance with the TS requirements.

NRC FORM 366A (4-95)

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NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION

'4-95I LICENSEE EVENT REPORT (LER)

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

QU IA I N NUMBER NUMBER Browns Ferry Unit 2 05000260 4 of 6 97 004 00 more specs is rerIuire, use s irioris copies o oim September 11, 1997 The snubber TS surveillances were incorporated into the refueling outage schedule.

September 19,1997 at 0835 hours0.00966 days <br />0.232 hours <br />0.00138 weeks <br />3.177175e-4 months <br /> CDT TVA personnel identified that vacuum breaker surveillances were scheduled to be performed while the unit was at power in conflict with TS requirements.

September 19," 1997 The vacuum breaker TS surveillances were incorporated in the refueling outage schedules.

D. Other S stems or Seconda Functions Affectedr None.

E'. Method of Discove NRC had questioned whether recent testing of snubbers in the standby liquid control system while the unit was at power was in conformance with Technical .Specification (TS) requirements.

TVA's review determined that previous testing of snubbers had not always been in compliance with the TS requirements.

Subsequently, TVA also identified that vacuum breaker surveillances were scheduled to be performed while the unit was at power, in conflict with TS requirements.

F,. 0 erator Actions:

None.

G. Safet S stem Res oases:

None.

CAUSE OF THE EVENT A. Immediate Cause:

The immediate cause of the condition was that some surveillances were not performed during refueling outages as required by TS.

NAC FOAM 366A I4-95I

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NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (4.95I LICENSEE EVENT REPORT (LER)

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

UN NUMBER I L VI I N NUMBER Browns Ferry Unit 2 05000260 5 of 6 97 -- 004 -- 00 mOfO SpSCO IS fSqUlfS USO S IUOflS COplOS 0 0fm B. Root Cause:

The root cause for not performing the TS surveillances within the correct timeframe was the ineffective control of outage schedules. .Specifically, Work Control personnel were not properly instructed to ensure that TS surveillances were a incorporated in refueling outage schedules. Additionally, procedure was not followed in that special surveillances were not incorporated in the refueling outage schedules in accordance with procedural requirements.

C, CONTRIBUTING FACTOR None.

IV. ANALYSIS OF THE EVENT Snubbers are designed to prevent unrestrained pipe or component motion under dynamic loads as might occur during an earthquake or severe transient, while allowing normal thermal motion during startup and shutdown. The consequence of an inoperable snubber is an increase in the probability of structural damage to piping and components as a result of a seismic or other event initiating dynamic loads.during To the verify snubber operability, functional tests are performed refueling outages. In this event, some snubber testing was performed prior to the outages. Namely, in the Unit 2, cycle 8 outage, 24 of the 41'nubbers tested were not performed during the refueling outage; and in the Unit 3, cycle 7 outage, 18 of the 34 snubbers tested were not performed during the refueling outage. However, the functional snubber tests were performed for all required snubbers on 18-month intervals.

Removal of snubber(s) for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to perform testing during power operation is permitted by TS 3.6.H. The operability requirements do not require consideration of associated system redundancy or impact until a snubber is out of service in excess of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The snubber within testing performed by TVA during power operations was completed the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed outage time. Thus, the snubber testing performed by TVA at power did not render any-system(s) inoperable and did not adversely affect plant personnel or the public.

The purpose of the suppression pool to the reactor building vacuum breakers is to open and equalize the air pressure between the suppression pool and the reactor building so that structural integrity is maintained. The functional testing ofthethese vacuum breakers on a of the ASME quarterly basis is necessary to satisfy, requirementsSection XI code requirements. In addition, the pressure suppression chamber reactor building vacuum breakers remain operable, both during the visual examinations and during the determination that the force required to open each vacuum breaker did not exceed 0.5 psid.

Thus, the testing of the vacuum breakers at power did not adversely NRC FoRM 366A (4-95I

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

LICENSEE EVENT REPORT (LER)

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

Y AR S aUEN IAL VI I N NUMBER NUMBER Browns Ferry Unit 2 05000260 6 of 6 97 -- 004 00 moro specs is require, use e rrione copies o 0fm affect plant personnel or the public.

Vo CORRECTIVE ACTIONS A. Immediate Corrective Actions t The Scheduling organization incorporated the missed snubber end vacuum breaker surveillances into the refueling outage schedule.

B. Corrective Actions to Prevent Recurrencet The snubber and the suppression pool to reactor building vacuum breaker surveillances were incorporated into the current refueling outage work schedule. A review of TS surveillance program was initiated to verify if other TS surveillances were met and incorporated into refueling outage -schedules. Based on this review, it was confirmed that these two surveillances were the only surveillances that were not incorporated in refueling outage schedules. Snubber and vacuum breaker functional tests were incorporated in standard refueling surveillance instructions to ensure that these activities are performed in future refueling outages. Work Control Management will ensure proper policy, guidance expectations, and )ob performance standards are provided to Work Control personnel in the outage organization.

VI. ADDITIONAL INFORMATION A. Failed Com onents:

None.

B. Previous LERs on Similar Events:

No previous LERS were, identified where TS surveillances were not properly incorporated into a refueling outage schedule.

VII+ COMMITMENTS Work Control Management will ensure proper policy, guidance expectations, and )ob performance standards are provided to Work Control personnel in the outag'e organization. This task will'be completed by March 16, 1998.

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

NRC FORM 366A (4-95)

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