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LER 94-004-00:on 941103,Unit 3 Outside Design Basis Due to Two of Three Required Safety Injection Pumps Inoperable. Control Switches for 3A & 3B Safety Injection Pumps Immediately Returned to automatic.W/941110 Ltr
	ML17352A885
Person / Time
Site:	Turkey Point
Issue date:	11/10/1994
From:	Knorr J, Plunkett T; FLORIDA POWER & LIGHT CO.
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
	L-94-286, LER-94-004-03, LER-94-4-3, NUDOCS 9411150397
	Download: ML17352A885 (10)
	v • d • e

~ W~J.~MI L I (ACCELERATED RIDS PROCESSIX~

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESS'ION NBR:9411150397 DOC.DATE: 94/11/10 NOTARIZED: NO DOCKET g FACIL:50-250 Turkey Point Plant, Unit 3, Florida Power and Light C 05000250 AUTH. NAME AUTHOR AFFILIATION KNORR,J.E. Florida Power & Light Co.

PLUNKETT,T.F. Florida Power & Light Co.

RECIP.NAME RECIPIENT AFFILIATION

+'h

SUBJECT:

LER 94-004-00:on 941103,Unit 3 outside design basis due to two of three required safety injection pumps inoperable.

Control switches for 3A & 3B safety injection pumps immediately returned to automatic.W/941110 ltr.

DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL SIZE:

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

NOTES:

RECIPIENT . COPIES RECIPIENT COPIES ID CODE/NAKE LTTR ENCL ID CODE/NAME LTTR ENCL PD2-2 PD 1 1 CROTEAU,R 1 1 INTERNAL OD/~OAB/hDSQ 2 2 AEOD/SPD/RRAB 1 1 FILE CENTER 02 1 1 NRR/DE/EELB 1 1

/DE/EMEB 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 NRR/PMAS/IRCB-E RGN2 FILE 01 1:j1 1

1 1

1 NRR/DSSA/SRXB RES/DSIR/EIB 1

1 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 h

NOTE TO ALL"RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE iVASTE! CO!hh'TACTTHE DOCL'ifEYTCONTROL DESK. ROONI P 1-37 (EXT. 504-2083 ) TO F LIXIINATE YOI:R NAZIE F ROTI DISTRIBUTION LISTS I'OR DOC!.'!hf EX'I'S YOU DON "I'l.'I'.I)!

FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 26 ENCL 26

FPL ZOV >0 tsgrr L-94-286 10 CFR 50.73 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Gentlemen:

Re: Turkey Point Unit 3 Docket No. 50-250 Reportable Event: 94-004-00 Unit 3 Outside the Design 'Basis Due to Two of Three Re uired Safet In 'ection Pum s Ino erable The attached Licensee Event Report, 250/94-004-00, is being provided in accordance with 10 CFR 50.73(a) (2) (i) and 10 CFR 50.73 (a) (2) (ii) .

If there are any questions, please contact us.

Ver <truly urs, Vice President Turkey Point Plant jek enclosure cc: Stewart D. Ebneter, Regional Administrator, Region II, USNRC Thomas P. Johnson, Senior Resident Inspector, USNRC, Turkey Point Plant 9411150397 941110 PDR ADOCK 05000250 S PDR '

an FPL Group company

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LICENSEE EVENT REPORT (LER)

DOCKET NUMBER (2) PAGE (3)

FACILITY NAHE (1)

TURKEY POINT UNIT 3 05000250 QF 5

TITLE (4)

UNIT 3 OUTSIDE THE DESIGN BASIS DUE TO TWO OF THREE REQUIRED SAFETY INJECTION PUMPS INOPERABLE EVENT DATE (5) LER NUMBER(6) RPT DATE (7) OTHER FACILITIES INV. (8)

HON DAY YR YR SEQ Rh HON DAY YR FACI( ITY NAMES DOCKET 6 (S) 004 00 10 94 OPERATING MODE (5)

POWER LEVE( (10) 100%

10 CFR 10 CFR 50.73 50.73 a a

2 2

iii LICENSEE CONTACT FOR THIS LER (12)

TELEPHONE NUMBER J. E. Knorr, Regulation and Compliance Specialist 305-246-6757 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

CAUSE SYSTEM COMPONENT MANUFACTURER NPRDSI CAUSE SYSTEM COHPONENT HANUFACTURER NPRDSI SUPPLEHENTAL REPORT EXPeCTeD (14) NO 0 Yes 0 expecTeD SUSHI S BIO N

DAY YEAR DATE (15)

(If yea, conylete EXPECTED SUBMISSION DaTE)

ABSTRACT (16)

At 0906 EST on November 3, 1994, during performance of the Unit 4 "A" train safeguards testing required by Technical Specifications, the two Unit 3 high head safety injection pumps'ontrol switches were incorrectly placed in a pull-to-lock position. This configuration resulted in both Unit 3 high head safety injection pumps being inoperable. The Unit 4A safety injection pump was functional but technically inoperable due to the requirements of the safeguards procedure. Additionally, the 4B pump was operable throughout this event. Recovery from this condition of the plant, assuming an accident, is covered under Turkey Point Emergency Operating Procedures. Since the current licensing basis assumes two high head safety injection pumps, the functionality or operability of the 4A and 4B pumps provide the systems required.

The cause of this event was human error by a licensed operator while 41 performing the safeguards test procedure on Unit 4. The condition was discovered by Operations management in its oversight role.

Corrective actions have been put in place to enhance communications and revise procedures to ensure correct system alignment.

0 LICENSE%VENT REPORT (LER) TEXTObNTINORTION FACILITY NAME DOCKET NUMBER LER NUMBER PAGE NO.

TURKEY POINT UNIT 3 05000250 94-004-00 02 oF 05 X. DESCRZPTXON OF THE EVENT At 0906 EST on November 3, 1994, with Unit 4 in Mode 5, during performance of the Unit 4 "A" train safeguards test, and with Unit 3 at 100% power, the two Unit 3 high head safety injection pumps'BQ:P] control switches [BQ:JS]

were incorrectly placed in a pull-to-lock position. This configuration resulted in both Unit 3 high head safety injection pumps being inoperable.

The Unit 4A safety injection pump was functional yet technically inoperable due to the 4A sequencer [JE:34] testing requirements of procedure 4-OSP-203.1, "Train A Engineered Safeguards Integrated Test." The 4B safety injection pump remained operable throughout the event. Technical Specification 3.5.2 requires three high head safety injection pumps to be operable when the opposite unit is in Mode 4, 5, or 6. Therefore Unit 3 was not in compliance with Technical Specification 3.5.2 for approximately 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months and 45 minutes. Also, Unit 3 was in Technical Specification 3.0.3 since no ACTION statement covered the condition found. No shutdown was initiated since the plant was returned to compliance with the Technical Specifications as soon as the condition was discovered.

Step 7.4.26 of 4-0SP-203.1 requires the 3A and 3B safety injection switches to be placed in the STOP position after completion of the pumps'ontrol "Loss of Offsite Power Coincident with Safety Injection" test. This operation normally returns the pumps to automatic such that they would respond to an actual safety injection signal. On November 3, however, the pump control switches were incorrectly placed in the pull-to-lock position thereby rendering the pumps inoperable.

The 3A and 3B pump control switches were discovered in the pull-to-lock position at approximately 1145 EST on November 3, and were immediately returned to the automatic start position. Unit 3 was returned to its design basis configuration at that time.

The condition was reported to the NRCOC at 1324 on November 3, 1994.

XX. CAUSE OF THE EVENT The cause of the event was a cognitive error by licensed personnel. The test director (a licensed operator) while restoring systems to normal, incorrectly directed another licensed operator to place the 3A and 3B safety injection pump control switches in the pull-to-lock position. The error was discovered by Operations management (in its oversight role) after approximately 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months and 45 minutes at which time the control switches were returned to the correct position. Procedure 4-OSP-203.1 requires the control switch to be placed in the STOP position. The switch position labels have the STOP position labeled "pull to stop," which may have contributed to the error.

The pre-job briefing of the Unit 3 operators for the Unit 4 safeguards test did not include adequate information about the expected Unit 3 system response (e. g., annunciation to be received) during the Unit 4 safeguards test.

LICENS REPORT (LER) TEXTNTINURTION FACILITY NAME DOCKET NUMBER LER NUMBER PAGE NO.

TURKEY POINT UNIT 3 05000250 94-004-00 03 oF 05 11Z . ANALYSIS OF THE EVENT S stem Descri tion:

Turkey Point Units 3 and 4 have four shared high head safety injection pumps (3A, 3B, 4A and 4B) which normally take suction on two refueling water storage tanks, with both units operating.

At the time of this event, all four safety injection pump suctions were aligned to the Unit 3 refueling water storage tank. When a safety injection signal is generated all four pumps receive a start signal. When only one unit is operating in Mode 1, 2, 'or 3, only three safety injection pumps are required to be operable. Therefore, in this event 3 safety injection pumps were required to be operable. Technical Specification 3.5.2, ACTION statement a, allows an operating unit with the opposite unit in Mode 4, 5, or 6 to have only two safety injection pumps operable for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .

In this ca'se, only one pump, the 4B, was operable for 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months and 45 minutes. The Unit 4A safety injection pump was also functional yet technically inoperable, due to test equipment attachments, and would have started upon demand.

The Unit 3 and 4 common control room has controls for all four safety injection pumps on both the Unit 3 and Unit 4 vertical panels. The switch positions are visible from the opposite unit switch positions. In this event, the control switches for the 3A and 3B pump on the Unit 4 vertical panel were placed in the pull-to-lock position; the control switches on Unit 3 vertical panel for the 3A and 3B pump would not run the pumps. Indication of the 3A and 3B switch positions in STOP or pull-to-lock is available at the Unit 4 switch'location and the Unit 3 and Unit 4 annunciator panels (H3/1 and H3/2) above the vertical panel switch locations.

Anal sis:

In the event of an accident, with the need for safety injection, Emergency Operating Procedure 3/4-EOP-E-O, "Reactor Trip or Safety Injection,"

'mmediate action step 4 requires the manual actuation of safety injection automatic actuation has not occurred. Even if this step is misdiagnosed, if two other success paths to initiate safety injection are subsequently available. The foldout pages for 3/4-EOP-E-0 and other transition procedures, for example 3/4-EOP-ES-0.1, "Reactor Trip Response," direct the actuation of safety injection based upon specific actuation criteria.

Foldout pages are required,to be monitored on a continuous basis throughout the use of the procedures. Therefore, the use of the EOP set will require the initiation of safety injection even the pull-to-lock position.

if the control switches are put in On November 4, 1994, two scenarios were run on the Unit 3 simulator at Turkey Point. In the first scenario the 3A and 3B pump vere in pull-to-lock on the Unit 4 control board and the 4A pump was out of service The 4B safety injection pump was the single failure assumed. The first scenario also assumed that the crew correctly diagnosed the need for safety injection and the use of 3/4-EOP-E-0 to direct the manual initiation of safety injection. The simulator crev diagnosed the condition and the Response-Not-Obtained section of step number 4 resulted in the manual initiation of safety injection. Step 8 of 3/4-EOP-E-0 also verifies that safety injection pumps are running and would lead to the starting of the pumps been missed in step 4 ~

if they had The second scenario was the same as the first from a system standpoint, however, the crew was directed to intentionally misdiagnose the need for safety injection and transfer to another procedure

LICENSEEOTENT REPORT (LER) TEXT ONTINURTION FACILITY NAME DOCKET NUMBER LER NUMBER PAGE NO.

TURKEY POINT UNIT 3 05000250 94-004-00 04 OF 05 as directed by 3/4-EOP-E-0 to determine still have safety injection manually if the condS.tions were present to initiated. This scenario also led to a success path because the foldout page requires the continual monS.toring of safety injectS. on actuation criteria. On November 5, 1994, simulator runs were conducted to determine the success path using different crews. In all cases safety injection was started as directed by 3/4-EOP-E-O.

These simulator exercises described above gave assurance that the use of Emergency Operating Procedures (EOPs) would successfully start the required safety injectS. on pumps even assuming a single active failure.

In 1991, Florida Power and Light Company (FPL) directed Westinghouse (NSSS and Fuel Supplier) to re-analyze the Turkey Point large break loss of coolant accident (LOCA), small break LOCA and non-LOCA analyses. These analyses are complete. The Westinghouse best-estimate LOCA methodology is currently under review by the NRC. These analyses justify the ne'ed for only one safety injection pump for a response to a LOCA. This best estimate LOCA analysis focuses on the use of a refined methodology to quantify the statistical combination of uncertainties. By using plant specific parameters such as system configuration, flows, operating conditions, delay times, percent of steam generator tubes plugged, etc,, the best estimate LOCA computer code can more accurately calculate the expected performance of the unit as a function of the event. Upon completion of the NRC review of the Turkey Point specific analyses, expected to be submitted in late 1995, the Final Safety Analysis Report design basis will be revised to reflect the results of the new analyses. These new analyses support the conclusion that only a single high head safety injection pump is required to mitigate an accident.

If, as in this event, the 4B pump is operable, the one safety injection pump required by the best estimate LOCA will start, and the EOPs will direct the start of more if necessary. Also note that the Unit 4A safety injection pump was also functional yet technically inoperable and would have started upon demand. Therefore, the health and safety of the public and plant personnel were not compromised.

For 20 minutes (11:25 to 11:45 on November 3, 1994) the operability of the 4B high head safety injection pump could have been affected by the design deficiency of the 4B sequencer discussed in LER 250-94-005.

This event is reportable in accordance with 10 CFR 50.73 (a) (2) (i) (B) and 10 CFR 50.73 (A) (2) (ii) (A) and (B) .

IV. CORRECTIVE ACTIONS The following corrective actions address the causes identified above and the Human Performance Evaluation System review conducted on this event.

1. Upon discovery of the misposition, the control switches for 3A and 3B safety injection pumps were immediately returned to automatic.

2. The event was discussed with each crew when taking watch, with a focus on the need for self checking. Operations department guidance will be developed to provide for procedures of this task type to be in the hands of the personnel performing the procedure steps.

3. Steps were added to each section of the safeguards procedure, 4-OSP-203.1 and 4-0SP-203.2, to independently verify the equipment lineup.

0 LICENSEEalENT REPORT (ZaER) TEXT 'NTINOATION FACILITY NAME DOCKET NUMBER LER NUMBER PAGE NO.

TURKEY POINT UNIT 3 05000250 94-004-00 05 oF 05 4 ~ The procedure steps for the stop of each safety injection pump are clarified to return to automatic.

5. The procedure will be revised to require each crew to be briefed on the effect of the test on common equipment prior to the beginning of each section of the safeguards procedure.

6. Caution tags will be installed on all common equipment during the safeguards test to further identify the operability of the opposite unit equipment .

7. An independent test oversight supervisor was assigned for the safeguards testing sequence V. ADDXTXOMAL XNFORMATXON EIIS Codes are shown in the format (EIIS SYSTEM: IEEE component function identifier, second component function identifier (if appropriate)].

During the past two years LER 250/93-003 dated January 23, 1993, was similar in nature with two trains of containment spray out of service at the same time due to personnel error.

ML17352A885

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