ML18101A312

LER 94-011-00:on 940929,manually-initiated Reactor Trip Signal Following Unplanned Closure of MSIV21 & 22 MS167. Caused by Personnel Error.Appropriate Procedures Changed. W/941019 Ltr

ML18101A312
Person / Time
Site:	Salem
Issue date:	10/19/1994
From:	Hagan J, Pastva M Public Service Enterprise Group
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-94-011-01, LER-94-11-1, NUDOCS 9411020250
Download: ML18101A312 (6)

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9 "Public Service Electric and Gas Company P.O. Box 236 Hanccicks Bridge, New Jersey 08038 Salem Generating Station October 19, 1994 U. s. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555

Dear S*ir:

SALEM GENERATING STATION LICENSE NO. DPR-75 DOCKET NO. 50-311

.UNIT NO. 2 LICENSEE EVENT REPORT 94-011-00 This Licensee Event Report is being submitted pursuant to the requirements of Code of Federal Regulation 10CFR50.73(a) (2) (iv).

Issuance of this repo~t is required within thirty (30) days of

• event discovery.

Sincerely yours, MJPJ:pc Distribution

,*- ~**: ~' 1 .-'~, :~;:

9411020250 941019 PDR ADDCK 05000311 S PDR The power is in your hanck 95-2189 REV 7-92

NRC FORCVI 366 (5,,92) e U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 5/31/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD

- . LICENSEE EVENT REPORT {LER) COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION AND RECORDS MANAGEMENT BRANCH (MNBB 7714), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF (See reverse for required number of digits/characters for each block) MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

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

Salem Generating Station Unit 2 05000311 1 OF 05 TITLE (4) Manually - Initiated Reactor Trip Signal Following Unplanned Closure of Main Steam I1=:nl::1 ;nn V::il,rP~ ?1 ::inrt ?? M~l/;

EVENT DATE (5) LER NUMBER l6 REPORT NUMBER l7\ OTHER FACILITIES INVOLVED (8 FACILITY NAME DOCKET NUMBER SEQUENTIAL REVISION . DAY MONTH DAY YEAR YEAR MONTH YEAR NUMBER NUMBER 05000

- FACILITY NAME* DOCKET NUMBER 09 29 94 94 -- 011 -- 00 10 19 94 05000 OPERATING THIS REPORT IS SUBMITIED PURSUANT TO THE REQUIREMENTS OF 10 CFR t: 7Check one or more (11 MODE (9) 1 20.402(b) 20.405(c) x 50.73(a)(2)(iv) 73.71(b)

I POWER LEVEL (10) I I 2a 20.405(a)(1 )(i) 20.405(a) (1) (ii) 20.405(a)(1) (iii) 50.36(c) (1) 50.36(c)(2) 50.73(a)(2)(i) 50.73(a)(2)(v) 50.73(a)(2)(vii) 50.73(a)(2)(viii)(A) 73.71 (c)

OTHER (Specify in Abstract below and in Text, NRC 20.405(a) (1) (iv) 50.73(a)(2)(ii) 50. 73(a) (2) (viii) (8) Form 366A) 20.405(a) (1 )(v) 50. 73(a) (2) (iii) 50-73(a)(2)(x)

LICENSEE CONTACT FOR THIS LER 12\

NAME TELEPHONE NUMBER (Include Area Code)

M. J. Pastva, Jr. Licensee Event Report Coordinator 609-339-5165 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 I

SUPPLEMENTAL REPORT EXPECTED 14 EXPECTED MONTH DAY YEAR SUBMISSION YES (If yes, complete EXPECTED SUBMISSION DATE) x NO.

DATE (15)

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

The Nuclear control Operator (NCO) . with balance of plant (BOP) responsibilities mistakenly_ closed main steam line isolation valves 21 and 22MS167. The other*operating crew NCOs recognized this mistake however, they had insufficient time to inter~ene.in order to avoid an automatic protective response. The BOP NCO, realizing the mistake, immediately initiated a manual reactor trip signal, at 0232 hours0.00269 days <br />0.0644 hours <br />3.835979e-4 weeks <br />8.8276e-5 months <br /> *on 9/29/94. Expected plant response occurred and Emergency Operating Procedures were entered. Main steam was isolated to limit Reactor Coolant system cool down and the Unit was stabilized in HOT STANDBY at 0317 hours0.00367 days <br />0.0881 hours <br />5.241402e-4 weeks <br />1.206185e-4 months <br /> (same day). This event is attributed to personnel error by the BOP NCO, as a result of inadequate self-checking and inattention to detail. A Human Performance Enhancement System evaluation of this event has been conducted. Appropriate personnel corrective actions have been taken. Observations of Operations personnel are ongoing to ensure adequacy of self verification techniques. During the trip recovery, an incorrect attempt was made to reset the Safeguards Equipment Controllers (SECS) and Technical Specification (TS) 3.0.3 was entered. Two SECs were reset and TS 3.0.3 was exited. Subsequent review showed the TS 3.0.3 entry was invalid and the involved overhead I alarm (OHA) response procedure was inadequate. Appropriate procedure chancres will be made reqardinq the attempt to reset the SECs.

NRC FORM 366 (5-92)

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION Salem Generating station DOCKET NUMBER LER NUMBER PAGE Unit 2 5000311 94-011-00 2 of 5 PLANT AND SYSTEM IDENTIFICATION:

Westinghouse - Pressurized Water Reactor Energy Industry Identification System (EIIS) codes are identified in the text as {xx}

IDENTIFICATION OF OCCURRENCE:

Manually Initiated Reactor Trip Signal Following Unplanned Closure Of Main Stearn Isolation Valves 21 and 22MS167 Event Date: 9/29/94 Report Date: 10/19/94 This report was initiated by Incident Report Nos.94-278 and 94-279.

CONDITIONS PRIOR TO OCCURRENCE:

Mode 1 Reactor. Power 28% Unit Load 230 MWe Ascension to full power was in progress and reactor power was being increased at 5% per hour. Shortly before 0232 hours0.00269 days <br />0.0644 hours <br />3.835979e-4 weeks <br />8.8276e-5 months <br /> on September 29, 1994, the Nuclear Control Operator (NCO) with balance of plant (BOP) responsibilities, was preparing to close main steam line drain valves21-24MS7,. in accordance with step 5.1.5.E. of

• procedure S2.0P-IO.ZZ-0004(Q), "Power Operation".

DESCRIPTION OF OCCURRENCE:

The BOP NCO mistakenly closed main steam line isolation valves (MSIVs) 21 and 22MS167 by removing the protective plastic bezel cover and depressing the valve control pushbuttons located on the BOP control panel. The mistake was observed by the other operating crew NCOs and they verbally informed the BOP NCO of the mistake. The other operating crew NCOs had insufficient time to intervene in order to avoid an automatic protective r~sponse. The BOP NCO, realizing the mistake, immediately initiated a Rec:tctor Protection System (RPS)

{JC} manual reactor trip signal, at 0232 hours0.00269 days <br />0.0644 hours <br />3.835979e-4 weeks <br />8.8276e-5 months <br /> on September 29 1994.

The manual trip was anticipatory to an automatic reactor trip signal, which occurred approximately five seconds later.

Plant response was as expected following the trip. Emergency*

Operating Procedures, EOP-TRIP-1, "Reactor Trip Or Safety Irijection"

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION Salem Generating Station DOCKET NUMBER LER NUMBER PAGE

.Unit 2 5000311 94-011-00 3 of 5 DESCRIPTION OF OCCURRENCE: (cont'd) and EOP-TRIP-2, "Reactor Trip Response" were entered and at 0237 hours0.00274 days <br />0.0658 hours <br />3.918651e-4 weeks <br />9.01785e-5 months <br /> (same day) main steam was isolated tQ limit cooldown of the Reactor Coolant System (RCS). ThE? Unit was stabilized in MODE 3(HOT STANDBY) and at 0317 hours0.00367 days <br />0.0881 hours <br />5.241402e-4 weeks <br />1.206185e-4 months <br /> Integrated Operating Procedure (IOP)-8, "Maintaining Hot Standby", was entered. At 0323 hours0.00374 days <br />0.0897 hours <br />5.340608e-4 weeks <br />1.229015e-4 months <br /> (same day), the Nuclear Regulatory Commission (NRC) was notified of this event, in accordance with 10CFR50.72(b) (2) (ii).

ANALYSIS OF OCCURRENCE:

Following the-BOP NCO's mistake, insufficient time existed to avoid an automatic prote~tive response-. The manual reactor trip was anticipatory to an expected automatic reactor trip and in accorda*nce with management expectations. It is intended to reduce the probability of challenge to plant safety systems.

Following the trip, 21 and 22 steam generator levels decreased to approximately llt. RCS temperature decreased to 530 degrees Fahrenheit and the remaining MSIVs, 23 and 24MS167, were closed to adequately limit the cooldown rate.

Prior to performing Step 5.1.5.E, "CLOSE 21-24MS7", the BOP NCO acknowledged his understanding of the intent of the step. However, as a result of inadequate self-checking and inattention to detail, he removed the bezel cover over the 21 and 22MS167 pushbutton controls and depressed the pushbuttons for the valves. The 21-24MS7 pushbuttons are located in the top portion of the control bezel, the 21-24MS18 pushbuttons (main steam warmup valves) in the middle, and the 21 and 22MS167 pushbuttons in the bottom portion of the bezel.

Following completion of immediate actions prescribed in EOP~TRIP-1, the BOP NCO was relieved by the Senior Nuclear Shift Supervisor (SNSS}. .

While performing EOP-TRIP-2, the Nuclear Shift Supervisor inadvertently crossed over the flow chart logic lines, and read two steps resulting in an inappropriate attempt to reset the Safeguards Equipment Controllers (SEC) {JC} through depressing the 230 volt (V)

Control C_enters Reset pushbuttons. This initiated the "Non-Mode Op" automatic test insertion (ATI) fault feature on the SECs, which caused the Control Room overhead Alarm (OHA) A-29, "2A, 2B, & 2C SEC TRBL" to annunciate. In accordance with the OHA response procedure, the three SECs (2A, 2B, and 2C) were declared inoperable and Technical Specification (TS) 3.0.3 was entered at 0245 hours0.00284 days <br />0.0681 hours <br />4.050926e-4 weeks <br />9.32225e-5 months <br /> (same day). The SEC automatic test faults tested satisfactorily and TS 3.0.3 was

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION

• - Salem Generating Station DOCKET NUMBER. PAGE LER NUMBER Unit 2 5000311 94-011-00 4 of 5 ANALYSIS OF OCCURRENCE: (cont'd) subsequ~ntly exited at 0338 hours0.00391 days <br />0.0939 hours <br />5.588624e-4 weeks <br />1.28609e-4 months <br /> (same day), following reset of 2A and 2B SECs. Subsequent review by Engineering showed that the SECs were not rendered inoperable by being reset therefore, the TS 3.0_.3 entry was invalid. In addition, this review showed that the alarm response procedure did not adequately address ATI alarms when either the. 11 230V Control Centers Reset" or the Emergency Loading Reset" pushbuttons are depressed.

As the result of prior excessive post~trip RCS cooldowns, design changes have been implemented and EOP-TRIP-1 has been revised to provide direction on throttling auxiliary f eedwater flow (reference LER 272/94-011-00). Engineering is conti~uing to assess additional corrective actions to minimize cooldowns following reactor trips.

APPARENT CAUSE OF OCCURRENCE:

This event is attributed to "Personnel Error", as classified in Appendix B of NUREG-1022. *This ~as exemplified by the BOP NCO's inadequate self-checking and inattention to detail, which resulted in the incorrect closing of 21 and 22MS167.

PREVIOUS OCCURRENCES:

Revie~ of documentation shows this is an isolated occurrence.

SAFETY SIGNIFICANCE:

This occurrence had minimal safety significance and is reportable pursuant to 10CFR50.73(a) (21 (iv). The RPS functioned as designed and the heat sink was maintained.

CORRECTIVE ACTION:

A Human Performance Enhancement System evaluation of this event has been conducted.

Based upon the circumstances of this event and other prior performance issues regarding the involved individual, appropriate disciplinary action has been taken, including removal from the station Operations Department.

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION Salem Generating Station DOCKET NUMBER LER NUMBER PAGE Unit 2 5000311 94-011-00 5 of 5 CORRECTIVE ACTION: (cont'd)

Observations of Operations personnel are ongoing to ensure adequacy of self verification techniques.

Appropriate procedure changes will be made to incorporate lessons learned from the s_equence of activities resulting in the resetting of the SEC controllers during performance of- EOP-TRIP-2.

The OHA response procedure associated with this event will be revised, as required.

Genera anager -

Salem Operations MJPJ:pc SORC Mtg.94-081