ML17328A616

Responds to Generic Ltr 89-19 Re Safety Implications of Control Sys in LWRs (USI A-47).Both Units Have Steam Overfill Protection Sys That Would Automatically Prevent Water Carryover Into Steam Lines If Control Sys Failed

ML17328A616
Person / Time
Site:	Cook
Issue date:	03/20/1990
From:	Alexich M INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
REF-GTECI-A-47, REF-GTECI-SY, TASK-A-47, TASK-OR AEP:NRC:1106, GL-89-19, NUDOCS 9003270334
Download: ML17328A616 (7)

Text

ACCELERATED DIRIBUTION DEMON~TION SY%i"EM INFORMATION DISTRIBUTION SYSTEM (RIDS)

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ACCESSION NBR: 9003270334 DOC. DATE: 90/03/20 NOTARXZED: YES DOCKET FACIL:50-315 Donald C. Cook Nuclear Power Plant, Unit 1, Indiana 6 05000315 50-316 Donald C. Cook Nuclear Power Plant, Unit 2, Indiana 6 05000316, AUTH. NAME AUTHOR AFFILIATION ALEXICH,M.P.

NOTES'EGULATORY Indiana Michigan Power Co. (formerly Indiana G Michigan Ele RECIP.NAME RECIPIENT. AFFILIATION R Document Control Branch (Document Control Desk)

SUBJECT:

Provides response to Generic Ltr 89-19 re A-47:safety implications of control sys in LWR nuclear po r plants.

DISTRIBUTION CODE: A001D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: OR Submittal: General Distribution S RECXPIENT COPIES RECIPXENT COPIES A ID CODE/NAME LTTR E CL ID CODE/NAME LTTR E CL PD3-1 LA 1 PD3-1 PD 1 GXXTTER,J. 5 INTERNAL: NRR/DET/ECMB 9H NRR/DOEA/OTS B1 1 NRR/DST 8E2 NRR/DST/SELB 8D NRR/DST/SICB 7E NRR/DST/SRXB 8E NUDOCS-ABSTRACT 0 ENB OGC/HDS 1 REG FILE 01 RES/DSIR/EIB EXTERNAL: LPDR NRC PDR NSIC R

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NO'IE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTEl CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISHUBUTION LISIS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 21 ENCL 1

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Indiana Michigan Power Company P.O. Box 16631 Columbus, OH 43216 AEP:NRC:1106 Donald C. Cook Nuclear Plant Units 1 and 2 Docket Nos. 50-315 and 50-316 License Nos. DPR-58 and DPR-74 GENERIC LETTER 89-19, ISSUE A-47: SAFETY IMPLICATIONS OF CONTROL SYSTEMS IN LWR NUCLEAR POWER PLANTS U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Attn: T. E. Murley March 20, 1990

Dear Dr. Murley:

The following information is provided in response to Generic Letter 89-19. Generic Letter 89-19 recommends that licensees with light water reactor (LWR) nuclear power plants provide an automatic steam generator overfill protection system. The purpose of this system is to prevent water carryover into the main steam lines.

Both Cook Nuclear Plant units have an automatic steam generator overfill protection system, designed by Westinghouse that meets the design and functional testing criteria described in Section 2a and 2b of Enclosure 2 of the generic letter. This overfill protection system has been in operation since the initial startup of each unit.

Upon high water level in a steam generator, the steam generator overfill protection system will initiate a trip of the main feedwater-pumps (and the main feedwater pumps discharge isolation valves) and close both the main feedwater regulation valves and the main feedwater isolation valves. Our design is based on automatic initiation when two-out-of-three high steam generator level signals are present. The three high steam generator level signals provide input into two protection logic trains. Output signals from each protection train trip redundant main feedwater regulation valve solenoids thereby ensuring closure of these valves. In addition, the steam generator overfill protection signals trip the main feedwater pumps (and the main feedwater pumps discharge isolation valves) and the main feedwater isolation valves. The portion of the overfill protection system from the level sensors through the valve trip signals are safety grade, physically separated between trip channels and between trains. Each channel and each train are powered by independent IE power sources.

9003270334 900320 ooi PDR ADOCK 050003i5 r aI l(P

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Dr. T. E. Murley AEP:NRC:1106 In addition, manual action can be initiated which could close the main feedwater regulating and isolation valves, and trip the main feedwater pumps and their'ischarge isolation valves.

Technical Specification Section 3/4.3.2, "Engineered Safety Feature Actuation System Instrumentation," requires channel checks, channel calibrations and channel functional tests to be performed at defined intervals to the safety grade portions of the instrument channels.

This verifies the operability of the instrument channels.

Appropriate plant procedures are in place to perform the surveillance required by the above mentioned technical specifications. The plant's Technical Specifications also require appropriate limiting conditions of operation for the steam generator overfill protection system channels.

In conclusion, we believe that Cook Nuclear Plant has a steam generator overfill protection system that would automatically prevent water carryover into the steam lines even if the steam generator water level control system partially or completely failed.

This letter is submitted pursuant to 10 CFR 50.54(f) and, as such, an oath statement is enclosed.

Sincerely, M. . A xich Vice President ldp Attachment cc: D. H. Williams, Jr.

A. A. Blind - Bridgman R. C. Callen G. Charnoff A. B. Davis - Region III NRC Resident Inspector - Bridgman NFEM Section Chief

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COUNTY OF FRANKLIN Milton P. Alexich, being duly sworn, deposes and says that he is the Vice President of licensee Indiana Michigan Power Company, that he has read the forgoing Response to Generic Letter 89-19, Issue A-47: Safety Implications of Control Systems in LWR Nuclear Power Plants and knows the contents thereof; and that said contents are true to the best of his knowledge and belief.

Subscribed and sworn to before day of me this 1 199

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NOTARY PUBLIC R)TA D. HILL OHI(

NOTARY PUELIC. STATE OF

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