ML18036A282

LER 91-013-00:on 910605,loss of Primary Containment Integrity Occurred When Both Drywell Personnel Airlock Doors Opened Due to Personnel Error.Operating & Maint Instructions revised.W/910705 Ltr

ML18036A282
Person / Time
Site:	Browns Ferry
Issue date:	07/05/1991
From:	Wetzel S, Zeringue O TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-91-013-01, LER-91-13-1, NUDOCS 9107120243
Download: ML18036A282 (18)

Text

ACCELERATED DT TRIBUTION DEMONS TION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9107120243 DOC.DATE- 91/07/05 NOTARIZED: NO DOCKET FACIL:50-260 Browns Ferry Nuclear Power Station, Unit 2, Tennessee 05000260 AUTH. NAME'UTHOR AFFILIATION WETZEL,S.A. Tennessee Valley Authority ZERINGUE,O.J. Tennessee Valley Authority RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 91-013-00:on 910605,tech spec violation ocurred following loss of primary containment. Caused by personnel r.

error. Corrective acitions include training for plant personnel 6 procedure revisions.W/910705 ltr.

DISTRIBUTXON CODE: IE22T COPIES RECEIVED:LTR ENCL J Jincident SIZE: V TITLE: 50.73/50.9 Licensee Event Report (LER), Rpt, etc.

NOTES RECIPIENT ID CODE/NAME COPIES LTTR ENCL 'DRECIPIENT CODE/NAME COPIES LTTR ENCL KREBS,M. 1 1 HEBDON,F 1 1 ROSS,T. 1 1 INTERNAL: ACNW 2 2 ACRS 2 2 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1 AEOD/ROAB/DSP 2 2 NRR/DET/ECMB 9H 1 1 NRR/DET/EMEB 7E 1 1 'RR/DLPQ/LHFB10 -1, 1 NRR/DLPQ/LPEB10 1 1 NRR/DOEA/OEAB 1 1 NRR/DREP/PRPB11 2 2 NRR/DST/SELB 8D 1 1 NRR/DST/SICB8H3 1 1 N .DST/SZLB8D1 1 1 NRR/DST/SRXB 8E RES/DSIR/EIB 1

1 1

1 EG RGN2

~LE~FILE 01 02 1 1

1 1

EXTERNAL: EGGG BRYCE,J.H 3 3 L ST LOBBY WARD 1 1 NRC PDR 1 1 NSXC MURPHY,G.A 1 1 NSIC POORE,W. 1 1 NUDOCS FULL TXT 1 1 NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE iVASTE!-CONTACTTHE DOCUMENT CONTROL DESK, ROOib'I PI-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!

FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 33 ENCL 33

0>> 0 Tennessee Vattey Autleiity. Post Offce Box 2000. Decatur,'Alabaina 35609 O. J. 'Ike'eringve Vice President, Browns Ferry Operations July 5, 1991 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington,,D.C. 20555

Dear Sir:

TVA BROWNS FERRY NUCLEAR PLANT (BFN) UNIT 2 DOCKET NO. 50-260 FACILITY OPERATING LICENSE DPR-52 REPORTABLE, OCCURRENCE REPORT BFRO-50-260/91013

'The enclosed report provides details concerning a technical specification violation that occurred following the breach of primary containment that occurred when both drywell airlock doors were simultaneously open. This report is. submitted in accordance with 10 CFR 50.73(a)(2)(i).

Very truly yours, TENNESSEE VALLEY AUTHORITY

0. J. Zerzngue Enclosure cc: see page 2 910712024 FOR'DOCK 0910705 i000260 PDR

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UPS. Nuclear Regulatory Commission July 5, 1991 cc (Enclosure):

INPO Records Center Suite 1500 1100 Circle 75 Parkway Atlanta, .Georgia 30339 NRC Resident Inspector, BFN Regional Administration U.S. Nuclear Regulatory Commission Office of Inspection and Enforcement Region II 101 Marietta Street, Suite 2900 Atlanta, Georgia 30323'hierry M. Ross U.S. Nuc3.ear Regulatory Commission One White Flint, North 11555 Rockville Pike .

Rockville, Maryland 20852

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NRC Form 366 CLEAR REGULATORY COMMISSION Approved OHB No. 3150-0104 (6-89) Expires 4/30/92 LICENSEE EVENT REPORT (LER)

FACILITY NAME (1)

B w F ni V'. [DOCKET NUMBER (2)

TITLE (4) i N Y ISEqUENTIAL I )REVISION) ( ) / FACILITY. NAMES IDOCKET NUHBER(S)

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I I I I I I l I 070 59 I I 1

I OPERATING I ITHIS REPORT IS SUBMITTED'PURSUANT TO THE RE()UIREHENTS OF 10 CFR g' MODE I m wi N IZO 402(b) F20.405(c) )50.73(a) (2) (iv) )73.71(b)

POWER I IZO 405(a)( l)(i) F50.36(c)(l) )50.73(a) (2) (v) [73.71(c)

LEVEL I [20.405(a)( l)(ii) [50.36(c)(2) ]50.73(a)(2)(vii) (OTHER (Specify in (20.405(a)( l)(iii) I&I50.73(a)(2)(i) [50.73(a)(2)(viii)(A) ( Abstract below and in (20.405(a)( l)(iv) )50.73(a)(2)(ii) (50.73(a)(2)(viii)(B) [ Text, NRC Form 366A)

.4 7 NAME

.I AREA CODE I lin wr A.W 1 NT F IREPORTABLEI I I I IREPORTABLEI I I NT P T T 0 14 I >

SUBMISSION I I I f m 1 P D B 0 T 1 ABSTRACT (Limit to 1400. spaces, i.e., approximately fifteen single-space typewritten lines) (16)

On June 5, 1991 at approximately 0245 a 'loss of primary containment integrity occurred when both drywell personnel airlock doors were opened. This condition occurred after the interlock which prevents, both doors from being simultaneously open was disarmed.

The root cause of this event was personnel error. The individual involved (utility, non-licensed) performed unauthorized work by disarming the interlock on the drywell airlock. A contributing cause of this event was the lack of action taken by those in the direct area when the event took place.

TVA's corrective actions to address the" specifics of this event included general and specialized training for plant personnel, procedure revisions to ensure Operations personnel are responsible for the operati'on of the drywell doors, and personnel corrective action in accordance with TVA policy. In addition, TVA performed an independent review to identify areas in which improvements may be prudent to further enhance maintenance-related activities and to reinforce requisite operational attitudes. This review resulted in additional procedure revisions, guidelines to enhance pre-test briefings and identification of future training upgrades.

NRC Form 366(6-89)

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NRC Form 366A U. S CLEAR REGULATORY COMMISSION Approved OMB No. 3150-0104 (6-89) Expires 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) IDOCKET NUMBER (2)

)SEQUENTIAL / (REVISION/ /' ) (

I I I I I I rw rr TEXT (If more space is required, use additional NRC Form 366A's) (17)

On June 5, 1991 at approximately 0245 a loss of primary containment integrity occurred when both drywell personnel airlock doors were opened. This condition occurred after the interlock which prevents both'doors from being simultaneously'pen was disarmed.

During the power ascension test program, entries were required to verify proper thermal expansion of primary system piping. This testing was to be performed under Test Instruction (TI) 190, t , with reactor coolant system pressure at approximately 150 psig. Mechanical Maintenance craftsmen were designated to operate the drywell airlock doors. These individuals were the assigned and qualified personnel to perform this task.

At approximately 0040 on June 5, 1991 three Mechanical Maintenance craftsmen were dispatched to perform the task of operating the airlock doors to support the thermal expansion testing. After supporting three entries into the drywell to determine the radiological conditions, a brief discussion took place between one of the three maintenance craftsmen and a Radiological Controls technician. Based on this discussion the craftsman understood it was acceptable to defeat the airlock interlock and open both inner .and outer doors, providing an unobstructed pathway into the drywell. After defeating the .airlock interlock, the craftsman reported his action to his foreman and general foreman. These individuals also did not question this action and failed 'to notify the Shift Operations Supervisor (SOS).

The condition of a breached primary .containment remained in place, until approximately 0600 on June 5, 1991,'when the status of the airlock was questioned and the condition reported to the SOS. Following this, notification the SOS took appropriate actions and reestablished primary containment integrity.

't the time of this event Unit 2 was in the startup mode with reactor moderator temperature of 365 degrees Fahrenheit and reactor vessel pressure of 150 psig. No fuel handling or operations over spent fuel were in progress. The loss of primary containment is a violation of Technical Specification 3.7.A.2, which 'is reportable in accordance with 10 CFR 50.73(a)(2)(i).

TVA is performing, an assessment of the safety significance of this event. The results of this assessment will be reported in a revision to this LER.

NRC Form 366(6-89)

ii 0 NRC Form 366A U. S. LEAR REGULATORY COHHISSION Approved OHB No. 3150-0104 (6-89) Expires 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAHE (1) IDOCKET NUHBER (2)'

/SEQUENTIAL / /REVISION/

I Y I I I I wn TEXT (If more space is required, use additional NRC Form 366A's) (17)

The root cause of this event was personnel error. The Mechanical Maintenance craftsman (utility, non-licensed) performed unauthorized work by disarming the interlock on the drywell airlock. Prior to this act the craftsman had received no direction from his supervisor or the SOS to perform this task. ln addition, the craftsman did not have written authorization allowing him to perform this work. A contributing cause of this event was the lack of action taken by those in the direct area when the event took place.

There have been no previous occurrences of loss of primary containment integrity.

Corrective actions have been implemented in several areas to address the specifics of this event. The areas and their respective corrective action(s) are provided below.

modified the assigned scope of work. The foreman and general foreman failed to communicate to the SOS the scope change of the work activity after becoming aware of it.

Q training package and conducted employee training sessions for plant personnel from June 7 through June 12, 1991. These sessions provided final event description; plant personnel responsibilities; SOS responsibility/authority; attitude and response to issues; and specific examples of previous events involving poor foreign material control, failures to perform adequate self-verification and problems associated with configuration control and equipment manipulation.

authorization and work documentation as required by plant procedures.

has trained maintenance craft and craft supervision on the requirements for the performance and documentation of assigned work. 1VA will also provide more in-depth training and will include this type of training in the craft annual requalification certification.

3. Pr h n Ev t n Risks and consequences associated with changing the method of defeating interlocks were not adequately reviewed or assessed for applicability during a 1987 revision of the procedure for defeating the interlocks.

NRC Form 366(6-89)

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NRC Form 366A U. S LEAR REGULATORY CONHISSION Approved OHB No. 3150-0104 (6-89) Expires 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) IDOCKET NUMBER (2)

I I I SEQUENTIAL I I REVISION I I I I I I I I I Br F r n' TEXT (If more space is required, use additional NRC Form 366A's) (17) tv t Operating instructions have been revised to ensure Operations personnel are responsible for operation of the drywell doors.

Maintenance instructions for defeating drywell interlocks have been revised to ensure correct drywell airlock door status is indicated in the control room with the interlocks defeated, and to remove responsibility and authority of operation of the drywell airlock from 'the Maintenance craft. A review of over 2000 plant procedures to ensure that interlock mechanisms are properly controlled has been completed. Based on the results of this review 36 procedures are being revised to improve communications.

personnel on several occasions to emphasize the importance of recognizing that BFN is becoming an operating plant, including the increased technical specification and operating requirements which would be in effect. Discussions included emphasis on correct job performance (e.g., ensure adequate time is taken; ensure each activity is clearly understood, if not, stop; if equi.pment failures occur, ensure proper actions are taken to determine root cause; self-checking). Several in-house assessments, including independent reviews (e.g., Operational Readiness Review, Senior'anagement Assessment) were conducted to assess the readiness of personnel to resume operations. 'While significant improvements were noted, management recognized that continuous, sustained emphasis and actual operating performance would be necessary to obtain desired levels of excellence. Frequent management assessments of performance were planned during initial operations..

Qgzr~~ty~~tj,~n Training as discussed in item 1 above was given to plant personnel. Site Quality Assurance (QA) performed surveys to determine the effectiveness of this training. Based on these surveys, additional training was

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provided in the maintenance area. In addition, the site Training department has enhanced its program on the requirements of the. plant's safety barriers and the responsibility to maintain their effectiveness.

5 ~ln .zqp~r', yt~Zg~czgg~lctj.eg The personnel involved performed unauthorized work in violation of plant procedures.

action in accordance with TVA policy.

In addition, TVA management performed an independent review of the event to identify areas in which improvements may 'be prudent 'to further enhance maintenance-related activities and to reinforce requisite operational attitudes. This review resulted in the development of the comprehensive set of improvements listed below.

.NRC Form 366(6-89),

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NRC Form 366A V. S. EAR REGULATORY COMMISSION Approved OHB No. 3150-0104 (6-89) Expires 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) IDOCKET NUMBER (2)

I I I ISEQUENTIAL I IREVISIONI I . I I I I I I I I TEXT (If more space is required, use additional NRC Form 366A's) (17)

- The plant instruction governing work request control, Site Director's Standard Practice (SDSP) 7.6, contained adequate controls to ensure operations notifications and authorization prior to commencing work. The procedure has, however, been enhanced to improve the process for notifying Operations of the status of in-progress work.

Specifically, it has been revised to ensure that if during performance of a work order (WO) any significant delays (over four hours) and scope changes occur, the SOS and unit operator are notified. The work planner's guide has also been revised to reflect this enhancement. In addi.tion, f'r work that affects certain critical systems, a "red sheet" must be filled out and inserted in the front of the work package as a flag to alert craftsmen of potential adverse impacts on plant operations.

SOS turnover meetings, General Operating Instruction 300-1, Attachment A, g}$

t, was revised to clearly identify the indivi.duals scheduled to to include a attend the shift turnover. The turnover checklist was also revised listing of power ascension tests that would be carried over into the oncoming shift., Also, the checklist now requires the listing of prejob briefings to ensure the oncoming shift receives a briefing on the work activities/test activities in progress.

QA Ri~v' The site QA organization performed a review of all open WOs ~ No WOs were identified where Operations notifications were not being made. The review revealed that 12 of the WOs required minor changes or improvements in the way Operations notifications were being provided, and 14 WOs were unnecessary and needed to be closed or canceled. TVA determined that no problems would have resulted from execution of these work orders. The remaining WOs were found to have adequate scope and work controls. QA also independently reviewed over 700 o'f the procedures discussed previously in Item 3, v t t To enhance the conduct of job briefings, guidelines have been issued, to test directors to reemphasize compliance with procedural requirements for conducting briefings for power ascension testing. These guidelines require that pretest briefings be held on the shift during which the test is performed; that personnel directly or indirectly involved in performance of the test be present at the briefings; and that the test director conduct two pretest briefings: one prior to the test crew assuming shift duties (a general test overview, usually at the Operations shift turnover meeting) and a second prior to commencing the test (a detailed briefing). Briefings will ensure, the test crew understand the test criteria, expected plant responses, and required actions.

have been addressed, TVA reviewed the task qualification process and found it to be satisfactory. In addition, QA will monitor the implementation of this program on an ongoing basis to evaluate the adequacy and effectiveness of the program.

NRC Form 366(6-S9)

(Qi il NRC Form 366A U. S LEAR REGULATORY COHHISSION Approved OHB No. 3150-0104 (6-89) Expires 4/30/92 LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) IDOCKET NUMBER (2)

I I I I SEQUENTIAL I lREVISIONI I I I I I I I I I F F TEXT (If more space is required, use additional NRC Form 366A's) (17)

6. w v' To ensure that support activities are completely specified and documented, TVA reviewed the power ascension tests. Nineteen tests were reviewed; seven of which were improved.

' v TVA reviewed the, current 'STA training 7 ~

program, which includes senior reactor operator qualification, and found it adequately covers. primary containment requirements. Interviews with individual STAs found them knowledgeable of these requirements.

8. ~m training t

program which foremen TVA is developing will attend.

a continuing supervisory obtain the applicable access level, TVA reviewed access levels of site personnel and changed the level of 108 individuals.

10. v' 't v't' To ensure proper control by Operations, TVA reviewed other critical activities, such as those related to fire protection, radiation monitors, and high 'radiation doors. No deficiencies were identified.

11. /gal m t To preclude a similar event from occurring on BFN's secondary containment airlocks, TVA checked secondary containment interlocks and verified proper functionality.

12. int n n M n m nt t t To ensure that BFN has an optimum Maintenance management organization, TVA will evaluate the existing two-level Maintenance supervisory structure.

TVA's June 13, 1991 letter from D. A. Nauman to S. D. Ebneter previously committed to perform these corrective actions.

MM IENT TVA will perform an assessment of the safety significance of this event. The results of this assessment will be reported in a revision to this licensee event report. This revision should be submitted by August 5, 1991.

NRC Form 366(6-89)

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