ML18153D323

LER 93-001-00:on 930420,RHR Rendered Inoperable When CC Sys Flow Heat Exchanger Inadvertently Isolated.Caused by Cognitive Personnel Error.Evaluation of Decay Heat Removal Sys Configuration Will Be performed.W/930430 Ltr

ML18153D323
Person / Time
Site:	Surry
Issue date:	04/30/1993
From:	Kansler M VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
93-270, LER-93-001-03, LER-93-1-3, NUDOCS 9305070101
Download: ML18153D323 (6)

Text

ACCEL.ERATED DOCUlvlEN'f DIS'TRIBU'fION SYSTEM

_REGULAT~ INFORMATION DISTRIBUTIO~STEM (RIDS)

ACCESSION ,NBR:9305070101 DOC.DATE: 93/04/30 NOTARIZED: NO DOCKET#

FACin:50-281 Surry Power Station, Unit 2, Virginia Electric & Powe 05000281 AUTH.NAME AUTHOR AFFILIATION KANSLER,M.R. Virginia Power (Virginia Electric & Power Co.)

RECIP.NAME RECIPIENT AFFILIATION R

SUBJECT:

LER 93-001-00:on 930420,RHR rendered inoperable when CC sys l flow heat exchanger inadvertently isolated.Caused by cognitiv~ personnel error.Evaluation of decay heat D removal sys configur~tion will be performed.W/930430 ltr.

DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR L ENCL _, SIZE:_.>"----- s TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.

I NOTES:lcy NMSS/SCDB/PM. 05000281 A

REClPIENT COPIE*s RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL D PD2-2 LA 1 1 PD2-2 PD l 1 BUCKLEY,B 1 1 D INTERNAL: ACNW 2 2 ACRS 2 2 s AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1 AEOD/ROAB/DSP 2 2 NRR/DE/EELB 1 1 NRR/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/DRIL/RPEB 1 1 NRR/DRSS/PRPB 2 2 ~SA/SPLB 1 1 NRR/DSSA/SRXB 1 1 - ~ 02 1 1 RES/DSIR/EIB 1 1 RGN2 FILE 01 1 1 EXTERNAL: EG&G BRYCE,J.H 2 2 L ST LOBBY WARD 1 1 R NRC PDR 1 1 NSIC MURPHY,G.A 1 1 NSIC POORE,W. 1 1 NUDOCS FULL TXT 1 1 I NOTES: 1 1 D

I A

D D

NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, s ROOM Pl-37 (EXT. 504-2065) TO ELIMINATE YOUR NAME FROM DISTRIBUTJON LISTS FOR DOCUMENTS YOU DON'T NEED!

FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OP COPIES REQUIRED: LTTR 33. ENCL 33.

."'" I

10CFR50.73

... r Virginia Electric and Power Company Surry Power Station P.O.Box315 Surry, Virginia 23883 April 30, 1993 U.S. Nuclear Regulatory Commission Serial No.: 93-270 Document Control Desk SPS:BCB Washington, D. C. 20555 Docket No.: 50-281 License No.: DPR-37

Dear Sirs:

Pursuant to Surry Power Station Technical Specifications, Virginia Electric and Power Company hereby submits the following Licensee Event Report applicable to Surry Power Station Unit ~t

. BEPQRTNUMBER 50-281/93-001-00 This report has been reviewed by the Station Nuclear Safety and Operating Committe~

and will be forwarded to the Management Safety Review Committee for its review.

Very truly yours, .

Enclosure cc: Regional Administrator 101 lV.1:arietta Street, NW, Suite 2900 Atlanta, Georgia 30323 M. W. Branch

• NRC Senior Resident Inspector Surry Power Station 060061

~6250l&Ag~ 6;8ci~ia1 5.

e NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (6-~9) a APPROVED 0MB NO. 3150-0104 EXPIRES: 4/30/92

-ATED BURDEN PER RESPONSE TO COMPLY WTH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD LICENSEE EVENT REPORT (LERI COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS AND REPORTS MANAGEMENT BRANCH (P-530). U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1) 'DOCKET NUMBER (2) I .PAGE 131 Surry Power Station, Unit 2 o 15 Io Io Io 12 1 81 l 1 I loFI O 14 TITLE !4l Momentary Loss of Component Cooling Flow to Heat Exchanger Renders Residual Heat Re~oval Loop Inoperable -- Violation of Technical Specifications EVENT DATE (5) LER NUMBER 16) REPORT DATE 17) OTHER FACILITIES INVOLVED 18)

MONTH DAY YEAR YEAR ttt SEQUENTIAL NUMBER (\/( REVISION NUMBER MONTH DAY YEAR FACILITY NAMES DOCKET NUMBER(SI 01s1010101 I I 0 14 210 9 3 9 I 3 - 01011 - o lo oj4 3j 0 9 I 3 o,s,o,o,o, I I THIS REPORT IS SUBMITTED PURSUANT TO THE R~QUIREMENTS OF 10 CFR §: /Ch*ck one or more of th* following/ 111)

OPERATING MODE (9) N 20.4021b) 20.4061c) 50.7311H2lliv) 73.711b)

I 20.40611111)11) 50.38(c)l1) 50.7311112)M 73.711c)

POWER ,___

LEVEL n. 0 0 .___ ~ ~

110) '-1 1 20.40611H1llii)

-X 50.3111cll2)

B) 50.7311H211vlil

~

OTHER /S,,.cify in Absrrocr b*low *nd in Texr. NRC Form 11:lflllt=

20.4061*)11 Hilil so.1311l12111i ( .....__ 50.7311112llviii)IA) 366A) 20.4061aH1Hlv) 20.40611)11 )Iv) --- li0.7311H2Hii) 50.7311)12) (iii) 1--

50.7311H2HvliiHB) 50.7311)1211*)

LICENSEE CONTACT FOR THIS LER 112)

NAME TELEPHONE NUMBER M, R. Kansler, Station Manager AREA CODE 8 I O I 4 3 15 I 7 I - 13 I 1 18 I 4 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 113)

MANUFAC- MANUFAC-CAUSE SYSTEM COMPONENT TURER TURER I I I I I I I I I I I I I I I I I I I I I I I I I I I I SUPPLEMENTAL REPORT EXPECTED 1141 MONTH DAY YEAR EXPECTED SUBMISSION r-i YES_(lf yos, complot* EXPECTED SUBMISSION DATE/

DATE 1151 I I I ABSTRACT (Limir to 1400 ::paces. i.t1.* approxim.rttly fiftatm 1inglt1*1pac11 typewritten lint11) 1161 The operating loop of the Unit 2 residual heat removal system (AHR loop A) was rendered inoperable on April 20, 1993, at 2050 hours0.0237 days <br />0.569 hours <br />0.00339 weeks <br />7.80025e-4 months <br />. The event occurred with Unit 2 at cold shutdown when the component cooling (CC) system flow to the AHR loop A heat exchanger (2-RH-E-1A) was inadvertently isolated. This condition resulted when CC system trip valve 2-CC-TV-209A closed. The valve actuation occurred when an electrical lead in the valve's power circuit was inadvertently de-terminated by station electricians.

The control room annunciator for CC outlet header 1 A low flow alarmed when 2-CC-TV-209A closed. Control room operators responded immediately by directing electricians to terminate the electrical lead. The lead was terminated and 2-CC-TV-209A was reopened at approximately 2051 hours0.0237 days <br />0.57 hours <br />0.00339 weeks <br />7.804055e-4 months <br />. CC flow to 2-RH-E-1A .returned to normal.

_This event resulted in no safety consequences or implications since the loss of CC flow was immediately recognized and prompt corrective actions were taken to restore it. The event was caused by a cognitive personnel error in that inadequate information was provided for use in developing tagout instructions. To prevent recurrence, procedures that control the process of de-terminating electrical leads will be reviewed and strengthened, as appropriate. This event is being reported pursuant to 10 CFR 50.73(a)(2)(i)(B). .

NRC Form 366 (~9)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (6-891 APPROVED 0MB NO. 3150-0104 EXPIRES, 4/30/92 ATEO BURDEN PER RESPONSE TO COMPLY WTH THIS LIICENSEE E . REPORT (LER) RMATION COLLECTION REQUEST, so.a HRS. FORWARD

• ENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRA.NCH IP-5301. U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555. AND TO.

THE PAPERWORK REDUCTION PROJECT (3150-01041. OFFICE I

! FACILITY NAME Ill OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

I

• DOCKET NUMBER 121 LER NUMBER 161 PAGE 131 I VEAR REVISION Suriy Power Station, Unit 2 NUMBER

• 0 5 0 O O 2 8* 1 9 3 - 0 0 1 - 0 0 0 2 OF O4 TEXT /ff mom $p/JCO i* n,qui,-,J, Uiltl additioMI NRC Form 366A'*I 1171

1. O Q!:SCRIPTION OF THE EVENT The operating loop of the Unit 2 residual heat removal system (RHR loop A) was rer1dered inoperable on April 20, 1993, at 2050 hours0.0237 days <br />0.569 hours <br />0.00339 weeks <br />7.80025e-4 months <br />. The event occurred with Unit 2 at cold shutdown when the component cooling system flow to the RHR loop A heat exchanger (2-RH~E-1A) was inadvertently isolated.

The Unit 2 RHR system consists of two redundant loops (RHR loop A and RHR loop B).

Each loop has a pump [EIIS: BP,P] and a heat exchanger [EIIS: BP,HX] that is supplied with cooling water by the component cooling (CC) water system. Technical Specification 3.1.A.1.d requires that a minimum of two loops, consisting of any combination of reactor coolant system [EIIS: AB] loops or RHR loops, be operable when the average reactor coolant system (RCS) temperature is s 350 °F. At least one of the RCS or RHR loops is also required to be operating.

2-RH-P-1A FiiCS Loop A~~~~~~~~

Hlot Leg 2-RH-P-18 CC Loop A CC Loop B 2-RH-E-18 2-CC-TV-209A 2-CC-TV-2098 RCS Lo1,p B Cold Leg RCS Lot>p C Cold Leg RHR / CC Systems Simplified Diagram NRC F.orm 366A (6-891

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION 16-89\ APPROVED 0MB NO. 3150-0104 EXPIRES 4130/92 ATED BURDEN PER RESPONSE TO COMPLY WTH THIS LICENSEE EV- REPORT (LERI MATION COLLECTION REQUEST: 50.0 HRS. FORWARD

• C ENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH (P-5301, U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO THE PAPERWORK REDUCTION PROJECT (3150-01041, OFFICE OF MANAGEMENT AND BUDGET. WASHINGTON, DC 20503.

FACILITY NAME 111 DOCKET NUMBER 121 LER NUMBER 161 PAGE 131 Surry Power Station, Unit 2 YEAR I<> se~~~~~':L f:2 ~~v~s~~~

Q l5jOjOjOj 2j8[1 913 _ 01011-010013 OF O j4 TEX(/lf more space is n,quimd, use additional NRC Form 366A '*I 1171

1. 0 DESCRIPTION OF THE EVENT (Continued)

The: RCS loops were filled (with level in the pressurizer [EIIS: AB,PZR]), but not vented, and therefore not considered to be operable when this event occurred. RHR loop A was operating and RHR loop B was operable. CC flow to 2-RH-E-1A was isolated at 2050 hours0.0237 days <br />0.569 hours <br />0.00339 weeks <br />7.80025e-4 months <br /> when CC system trip valve [EIIS: CC,ISV] 2-CC-TV-209A closed. This condition rendered RHR loop A inoperable. The valve actuation occurred when an electrical lead (located behind the vertical board in the control room) in the valve's power circuit was inaclvertently de-terminated by station electricians. The electricians were implementing tagc,ut instructions that were intended to isolate power to sampling system (SS) trip valve

[EIIS: KN,ISV] 2-SS-TV-204A to facilitate maintenance on the valve.

The control room annunciator [EIIS: IB,FA] for CC outlet header 1A low flow, "CTMT CC OUT HDR 1A LO FLOW", alarmed when 2-CC-TV-209A closed. Control roorn operators responded immediately by directing the electricians to terminate the electrical lead. The lead was terminated and 2-CC-TV-209A was reopened at approximately 2051 hours0.0237 days <br />0.57 hours <br />0.00339 weeks <br />7.804055e-4 months <br />. CC flow to 2-RH-E-1A returned to normal.

This event is being reported pursuant to 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by the Technical Specifications.

2. O SAFETY CONSEQUENCES AND IMPLICATIONS This event resulted in no safety consequences or implications since the loss of CC flow was immediately recognized by control room operators and prompt corrective actions were taken (in approximately one minute) tornstore it.

Forc,9d RHR loop A flow continued during the event. In addition, decay heat was relatively low since the unit had been shutdown for 45 days (for refueling) and 68 new fuel assemblies had been loaded in the core. These factors, in conjunction with the prompt corrective actions, resulted in no measurable change in RCS temperature.

Furthermore, a refueling outage safety assessment had been performed which ensured that several alternate decay heat removal options were available, had they been needed:

a) The RHR loop B was operable and with local operator action could have been promptly placed in service. b) The A low head safety injection pump was operable and could have been placed in service from the control room to provide long term cooling flow

("feecj and bleed"). The source of water would initially be the refueling water storage tank J:EIIS: BP,TK] and subsequently by recirculating water from the containment sump.

c) The high head safety injection pumps [EIIS: BQ,P] were operable and could have been placed in service from the control room to provide cooling flow ("feed and bleed")

from 1he refueling water storage tank. Therefore, the health and safety of the public vyere not affected. '

NRC Form 366A 16-891

-*-* 1

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION APPROVED 0MB NO. 3150-0104 16-891 EXPIRES: 4/30/92 ATED BURDEN PER RESPONSE TO COMPLY WTH THIS LliCEN_SEE EV- REPORT (LERI MATION COLLECTION REQUEST: 50.0 HRS. FORWARD

• ENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH (P-5301. U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO I l"HE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE 1

OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME 11) DOCKET NUMBER 12) PAGE (31 LER NUMBER 161 YEAR  !:;::::::::: SEQUENTIAL ::::::::::: REVISION

[::::::::::: NUMBER  ;'.;'.;'.;::: NUMBER Surry Power Station, Unit 2 o 1s Io Io Io I 2 18 I 1 9 I 3 - o Io 11 - o !O O 14 OF O 14 TEXT /ff more Sl)IJCtJ is required, use addit}ona/ NRC Form 3156:A 's) 117) 3 .0 .c.AJJ..S..E ThE! root cause of this event was a cognitive station personnel error in that inadequate infc,rmation was provided for use in developing the tagout instructions for SS trip valve 2-SS-TV-204A. Specifically, the information included wire and terminal numbers, but did

• not identify the cable numbers and did not specify that the field side cables should be de-*terminated .

. A t)pographic error in the tagout instructions and a mislabeled electrical lead contributed to tl1is event. Th.e tagout instructions had not been independently verified with respect to t11e applicable drawings. These factors resulted in an incorrect electrical leod being de-terminated, which caused.2-CC-TV-209A to close.

4. O 1.M.MEDIATE CORRECTIVE ACTION{$}

Control room operators responded immediately to the "CTMT CC OUT HDR 1A LO FLOW" alarm by directing station electricians to terminate the electrical lead. The lead was terminated and 2-CC-TV-209A was reopened at approximately 2051 hours0.0237 days <br />0.57 hours <br />0.00339 weeks <br />7.804055e-4 months <br />.

5. 0 . AD[,)ITIONAL CORRECTIVE ACTION{$}

A Human Performance Enhancement System Root Cause Evaluation (HPES/RCE) was initiated on April 21, 1993, to determine the cause of the event.

6. O A.CJIONS TO PREVENT RECURRENCE Procedures that control the process of de-terminating electrical leads will be reviewed and strengthened, as appropriate.

The mislabeled electrical lead will be physically verified and labeled, as appropriate.

An evaluation of the decay heat removal system configuration during unit shutdowns will be p,erformed.

7. 0 .filM!LAR EVENTS LER $1-89-009-00 Inadvertent Isolation of Component Cooling Water to Operating RHR Heat Exchanger Due to Inadequate Awareness of System Configuration LER $2-86-004-00 Isolation of Component Cooling to Operating Residual Heat Removal Loop 8.0 MANUFACTURER/MODEL NUMBER N/A NRC Form 366A 16-891 .