ML17325A621

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LER 87-023-01:on 871109 Problem Discovered Re Fuses Required for Isolation Between Local Shutdown & Indication Panels. Problems Confirmed on 871222.Caused by Engineer Design Oversight.Design Changes made.W/880218 Ltr
ML17325A621
Person / Time
Site: Cook American Electric Power icon.png
Issue date: 02/18/1988
From: Beilman T, Will Smith
INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:
NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
RTR-REGGD-01.097, RTR-REGGD-1.097 IEIN-84-09, IEIN-84-9, LER-87-023-01, LER-87-23-1, NUDOCS 8802230067
Download: ML17325A621 (7)


Text

REGULATORY INFORMATION DISTR IBUTIQl'J SYSTEM (R IDS)

ACCESSION NBR: 8802230067 DOC. DATE: 88/02/18 NOTARIZED: NO DOCKET 0 FACIL: 50-315 Donald C. Cook Nuclear Poeer P AUTHOR AFFILIATION lant'nit ii Indiana 5 05000315 AUTH. NAME BEILMANiT. P. Indiana Michigan Power Co. (formerly Indiana 8. Michigan Ele SMITHi W. G. Indiana Michigan power Co. (formerly Indiana 5 Michigan Ele RECIP. NAME RECIPIENT AFFILIATION

SUBJECT:

LER 87-023-01: on 871109 problem discovered re fuses required for isolation between local shutdoen 8c indication panels.

Problems conf iTmed on 871222. Caused bg engineer design oversight. Design changes mode. W/880218 ltr.

DISTRIBUTION CODE: IE22D COPIES RECEIVED: LTR ENCL SIZE:

TITLE: 50. 73 Licensee Event Report (LER>i Incident Rpti etc.

REC IP IENT CQP IES REC I P IENT CQP IES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD3-3 LA 1 1 PD3-3 PD 1 1 WIGGINGTQNi D INTERNAL: ACRS MICHELSON 1 ACRS MOELLER 2 2 AEOD/DOA 1 AEOD/DSP/NAS 1 1 AEOD/DBP/ROAB AEOD/DBP/TPAB 1 1 ARM/DCTS/DAB 1 DEDRO 1 1 NRR/DEBT/ADS 0 NRR/DEBT/CEB 1 NRR/DEST/ELB 1 NRR/DEBT/ I CSB 1 1 NRR/DEST/MEB 1 NRR/DEBT/MTB 1 1 NRR/DEST/PSB 1 NRR/DEST/RSB 1 1 NRR/DEBT/SGB 1 NRR/DLPG/HFB 1 1 NRR/DLPG/GAB 1 NRR/DOEA/E*B 1 1 NRR/DREP/RAB 1 NRR/DREP/RPB 2 2 B 1 NRR/PM*8/ I LRB 1 1 REG FILE 02 1 RES TELFORD> J 1 1 IB 1 RES/DRPS DIR 1 1 RGN3 FILE 01 1 EXTERNAL: EG5G GROHi M FORD BLDG HOYi A 1 1 H ST LOBBY WARD LPDR 1 1 NRC PDR NSIC HARRIS' 1 1 NSIC MAYSi G TOTAL NUMBER OF COPIES REQUIRED: LTTR 46 ENCL 45

Indiana Michigan Power Company Cook Nuclear Plant P.O. Box 458 Z

Bridgman, MI 49106 616 465 5901 INDUNA NlCHtGAM POD February 18, 1988 United States Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555 Operating License DPR-58 Docket No. 50-315 Document Control Manager:

In accordance with the criteria established by 10 CFR 50.73 entitled Licensee Event Re ortin S stem, the following report is being submitted:

87-023-01 Sincerely, W. G. Smith, Jr.

Plant Manager WGS:afh Attachment cc: D. H. Williams, Jr.

A. B. Davis, Region M. P. Alexich III R. F. Kroeger H. B. Brugger R. W. Jurgensen NRC Resident Inspector J. F. Stang, NRC R. C. Callen G. Charnoff, Esq.

Dottie Sherman, ANI Library D. Hahn INPO PNSRC A. A. Blind M~pN P. A. Barrett/P. Lauzau

NRC Form 345 US. NUCLEAR REOULATOAY COMMISSION (943)

APPROVED OMB NO. 31500104 LICENSEE EVENT REPORT (LER) EXPIRES: 5/31/SB FACILITY NAME (I) DOCKET NUMBER (2) PA E 3 D. C. Cook Nuclear Plant Unit 1

"'"""Deficient Design Results in Failure to Provide 0 5 00 0315>OF05 Electrical Isolation Between Local Shutdown and Indication Panels EVENT DATE (5) LER NUMBER (5) REPORT DATE (7) OTHER FACILITIES INVOLVED (Sl MONTH OAY YEAR YEAR jPP SEQUENTIAL

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REVISION MONTH OAY YEAR FACILITYNAMES DOCKET NUMBERIS)

NUMBER NUMBER D.C. Cook Unit 2 0 5 0 0 0 3 1 1 0 9 8 7 8 7 0 2 3 0 1 0 0 5 0 0 0 THIS REPORT IS SUBMITTED PURSUANT T 0 THE REQUIREMENTS Of 10 CFR (Ir fCneclt one or more Of thr follovfinPI (11 OPERATINQ MODE (9) 20402(B) 20AOS(e) 50.73(e) (2) (N) 73.71(B)

POWE R 20AOS(e)(l ) (I) SOW(e)(I) 50,73(sl(2)(v) 73.71(c)

LEVEL

00) (vill)(BI 0 9 0 20AOS(s)II)(S) 50.35(el(2) 50.73(el(2)(vill OTHER (Specify In Abrtreet below enrf In Test, HRC Form 20AOS(e)(1)(ill) 50.73(e) (2) (I) 50.73(e) (2) (vllI) (AI 3SEAI 20AOS(e) (1)(N) 50.7 3(e) (2) (5) 50.73(e) (2) 20AOS( ~ )(1)(v) 50.73(e) (2)(llil 50,73(el(2)(rr)

LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER T. P. Beilman AREA CODE Instrumentation & Control Department Superintendent COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13) 616465-5901 CAUSE SYSTEM COMPONENT MANUFAC- REPORTABLE I g+(p. 'NoI MANUFAC. EPORTABLE TURER TO>>ROS: ROu%a. 4 CAUSE SYSTEM COMPONENT TURER TO NPRDS

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g A 'o&N " 'P P n N'n...... Sk4 o

.-8o SUPPLEMENTAL REPORT EXPFCTED (14) MONTH OAY YEAR EXPECTED SUBMISSION DATE (15)

YES (if yrr, complere EXPECTED SUSIeIISSIOH DATE) NO ABSTRACT fLlmit to 1400 epecer, I.r., rpprorrlmetrfy filtrrn elnpleeprcr typewritten Ilneel (IS)

The primary purpose of this supplemental report is to provide additional information regarding the sequence of events.

On November 9, 1987, during a review of an investigation con-cerning Regulatory Guide 1.97 compliance, it was discovered that a potential problem could exist involving the fuses required for isolation between the various Local Shutdown and Indication (LSI) panels (improperly located on Unit 2 and not incorporated into the existing design on Unit 1). On December 22, 1987 confirmed that a condition existed that, in the event of a fire it was local to a LSI panel, power (both normal and alternate) to some or all of the same units'emaining panels could have been lost.

The cause of the event was an oversight by design engineers in the design and verification process associated with the initial Appendix R modifications.

Fire watches were assigned to tour the affected areas. Design changes have been implemented which provide the necessary isola-tion in the event of a fire. To prevent recurrence the appro-priate engineering procedures have been prefaced to address this specific electrical isolation concern.

8802230067 880218 PDR ADOCK 05000315 NRC Form 355 S PDR

'OCKET NRC Form 366A U.S. NUCLEAR REGULATORY COMMISSION (943)

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVEO OMB NO. 3150-0104 EXPIRES: 8/31/85 FACILITY NAME (I) NUMBER (2) LER NUMBER (6) PAGE (3)

SEOUENTIAL REVISION YEAR ~@@ NUMBER NUMBER D.C. Cook Nuclear Plant Unit 1 0 5 0 0 0 3 1 5 8 7 0 2 3 0 1 0 OF 0 5 TEXT /lfmoro spsso /s isr)eked, oso sddi lions/ //RC Form 366A's/ (I2)

The primary purpose of this supplemental report is to provide additional information regarding the sequence of events leading up to the determination that the event was reportable.

Conditions Prior to Occurrence (Conditions date of discovery)

Unit 1 Mode 1 (power operation) 90 percent Reactor Thermal Power Unit 2 Mode 1 (power operation) 80 percent Reactor Thermal Power Descri tion of Event On November 9, 1987, during an investigation into the feasibility of using existing Reactor Coolant System Wide Range T-Hot and T-Cold indications (EIIS/AB-TI) for Regulatory Guide 1.97 com-pliance,it was discovered that a potential problem could exist involving the fuses (EIIS/FU) required for isolation between the various Local Shutdown and Indication (LSI) panels (EIIS/PL)

(improperly located on Unit 2 and not included in the existing design on Unit 1). On December 22, 1987 condition existed that, in the event of a it was confirmed that a fire local to an LSI panel, power (both normal and alternate) to some or all of the same units'emaining LSI panels could be lost. If powerwould was lost to all panels, those indications available locally be lost. In addition, all Wide Range T-Hot and T-Cold indications, 1 of 4 channels of pressurizer level indication (EIIS/AB-LI), and both trains of the Reactor Vessel Level Indication System (EIIS/AB-LI) would be lost in the control room. This condition is not consistent with the requirements of 10 CFR 50, Appendix R and has existed since initial installation of the Appendix R modifications (Unit 1 September, 1985; Unit 2 June, 1986)'.

With the exception of the sub'ject LSI panels, there were no inoperable components, systems or structures that contributed to this event.

The following provides the reason for time between (1) the date (November 9, 1987) that the configuration(i.e., a potential problem with the electrical isolation between power feeds to NRC FORM 3ddA (9 83)

u NRC Form 366A (94)3)

FACILITY NAME (I)

D.C. Cook Nuclear

'OCK LICENSEE EVENT REPORT (LER) TEXT CONTINUATION Plant Unit 1 0 ET NUMBER (2) 5 0 0 0 3 1 5 8 7 2 3 U.S. NUCLEAR REGULATORY COMMISSION LER NUMBER (6) jSI SEGUENTIAL 0

NUMBER APPROVEO OMB NO. 3150-0104 EXPIRES: 6/31/95 AIPieo REVISION 66'O NUMBER 0 1 0 3 PAGE (3)

QF 0 5 TEXT illmore spsoeis required, use sddicionsl llRC Form 3654's) (17)

Descri tion of Event (Continued)

Local Shutdown Indication panels) was initially questioned and (2) the date (December 22, 1987) when the known problem was re-ported. Specifically, on November 9, 1987 the engineer who iden-tified the concern initiated a Problem Report. Problem Reports are used to document either known nonconformances or potential nonconformances and to assure proper investigation into the documented concern. For the case reported in this LER, the engineer later concluded, on November 9, 1987, that the concern identified on the Problem Report was not a problem (i.e., a condition which was contrary to regulatory requirements was not identified). Therefore, the engineer did not forward the Problem Report to management. Approximately seven to nine days later, the engineer's supervisor questioned the engineer about the status of the concern. At that time (approximately, November 18, 1987) the supervisor concluded that the electrical isolation concern may have an impact on regulatory (10 CFR 50, Appendix R) compliance. Therefore, the supervisor had the Problem Report forwarded to the appropriate management (Problem Assessment Group), so that an investigation would be conducted pursuant to the procedural requirements which govern such an investigation.

On December 21, 1987 engineering and licensing reviews concluded that even though certain process variables required by 10 CFR 50, Appendix R could be lost in certain fire scenarios, sufficient alternative information was still available. Therefore, it was concluded that a regulatory compliance problem did not exist.

However, on December 22, 1987 it was concluded that a problem did exist. Specifically, a single fire might eliminate the redundant Alternative Shutdown Capability instrumentation required by 10 CFR 50 Appendix R, Section III.L. At this time (December 22, 1987), when this problem was first identified as reportable:

(1) the requirements of 10 CFR 50.72 were fulfilled (1650 hours0.0191 days <br />0.458 hours <br />0.00273 weeks <br />6.27825e-4 months <br />) and (2) a report per 10 CFR 50.73 was initiated.

In summary, on November 9, 1987, the engineer who had first questioned the LSI panel electrical isolation, concluded that a problem did not exist. On approximately November 18, 1987, the engineer's supervisor, through consultation with her assistant supervisor and a licensing engineer, concluded that the concern warranted formal investigation. On December 21, 1987 engineering and licensing concluded that the requirements of Appendix R were being fulfilled, in spite of electrical isolation concerns. On December 22, 1987, the conclusion was reached that certain concerns post-fire process variables (e.g., T-HOT and T-COLD) could not be assured. Therefore, appropriate reportability actions were initiated.

NRC FORM 366A

0) 63I

NRC Form 366A U.S. NUCLEAR REOULATORY COMMISSION (643)

LICENSEE EVEN REPORT (LER) TEXT CONTINUATION APPROVED OMB NO. 3150M(04 EXPIRES: 6/31/85 FACILITY NAME (I) DOCKET NUMBER (3) LER NUMBER (6) PACE (3) y 6 AR NUMSER

~ i W <5 R 5 V I5 I0 N Q M; 5 6 0 U 6 N T I A L ~

i&rr NUMBER D.C. Cook Nuclear Plant Unit 1 0 5 0 0 0 3 1 5 8 7 0 2 3 0 1 0 4 QF 0 5 TEXT /// more epeee /I requIred, uee eddi r)rrur//VRC Form 3564'5/ ()7)

Cause of Event The cause of the event was an oversight by design engineers in the design and verification process associated with the initial Appendix R modif ications.

Anal sis of Event The condition is not consistent with the requirements of 10 CFR 50, Appendix R, and as such, is not consistent with our design basis.

The event has been determined reportable per 10 CFR 50.73, (a)(2)(ii)(B). Appendix R requires that adequate instrumentation be available to ensure safe shutdown in the case of a single fire.

If a fire at one of the LSI panels had led to the loss of power to all of one Units'SI panels, Wide Range T-Hot and T-Cold indications would have been lost (both local and control room).

According to IE Information Notice 84-09, these process variables are requ'ired for safe shutdown. However, sufficient information would have been available to the operator for achieving safe shutdown in the use of the in-core thermocouple indications and/or the use of main steam pressure and saturation temperature curves.

If power was lost to all LSI panels due to a fire at any LSI panel location, all indications on all LSI panels would be lost. However, with the exception of Wide Range T-Hot and T-Cold, all of the process variables indicated locally at the LSI panels would not be required locally due to their availability in the control room and the fact that a fire at any LSI panel location would not require remote shutdown.

Therefore, for the reasons detailed above, that the condition reported in this LER represents neither a it has been concluded significant risk to public health and safety, nor a significant degradation of our Appendix R safe shutdown capability.

Corrective Actions Roving fire watches were assigned to tour the affected areas The on December 22, 1987 (LSI panel locations within both units).

roving fire watches were upgraded to continuous fire watches on December 24, 1987. These steps were taken to serve as an interim compensatory action until the necessary design changes could be implemented.

For Unit 2, design changes were implemented December 30, 1987 that removed the improperly located fuses and installed replacements to remedy the inadequacy. For Unit 1, fuses were installed on NRC FORM 35@A (9 63)

U.S. NUCLEAR REGULATORY COMMISSION

'OCKET NRC Form 366A (94)3)

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVED OMB NO. 3(50-0 I 04 EXPIRES: 6/31i65 FACILITY NAME ('I) NUMBER (3) LER NUMBER (6) PAGE (3)

YEAR oSs'EGUENTIAL REVISION NUMBER io. NUMBER D.C. Cook Nuclear Plant Unit 1 0 5 0 0 0 3 1 5 8 7 0 2 3 0 1 0 5 OF 0 5 TEXT ilfmore speosis seqoired, use eddirionel NRC Form 3654's) (17)

Corrective Actions (Continued)

December 29, 1987. The existing configuration now provides the electrical isolation necessary in the event of a fire. We believe that this condition is an isolated event. Although consideration of 10 CFR 50, Appendix R electrical isolation criteria in the engineering and design process is required, additional emphasis will be placed on these electrical isolation with requirements. The appropriate engineering procedures, dealing Appendix R design details, have been prefaced (via a letter) to include this electrical isolation concern. The letter was reviewed during a monthly training session (01/21/88) attended by electrical engineering personnel.

Failed Com onent Identification None Previous Similar Events None NRC FORM 366A (9 93I