ML20056E973

Summary of 930728 Meeting W/Util in Rockville,Md to Discuss Proposed Mods to Reactor Vessel Water Level Instrumentation, Per NRC Bulletin 93-03.List of Attendees Encl

ML20056E973
Person / Time
Site:	Clinton
Issue date:	08/09/1993
From:	Pickett D Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
IEB-93-003, IEB-93-3, NUDOCS 9308250361
Download: ML20056E973 (25)

Text

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'l i UNITED STATES (gs ' /g

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E NUCLEAR REGULATORY COMMISSION WASHINGTON D.C. 2055>-0001

....+ i August 9, 1993  :

Docket No. 50-461 I

LICENSEE: Illinois Power Company FACILITY: Clinton Power Station

SUBJECT:

MEETING

SUMMARY

OF JULY 28, 1993 On July 28, 1993, repremdatives of Illinois Power Company met with members of the NRC staff at fGC headquarter; in Rockville, Maryland, to discuss their proposed modificatio,1s to the reactor vessel water level instrumentation in accordance with the requirements of NRC Bulletin 93-03, " Resolution of Issues i Related to Reactor vessel Water Level Instrumentation in BWRs." The list of meeting attendees and handouts presented by Illinois Power Company at the meeting, are enclosed.

The licensee reques ted the meeting to discuss their plans to implement a design that is unique from other facilities. Divisions I and 2 (both divisions of low-pressure ECCS) would incorporate a keep-fill modification '

with water from the control rod drive (CRD) pumps maintaining a low flow to the condensing chamber to flush out non-condensible gases. Divisions 3 and 4 (high pressure core spray system) would not have a keep-fill system, but would incorporate a tie-in between the fuel zone and narrow range instrumentation such that the variable leg from the narrow range monitor connects with the reference leg of the fuel zone monitor. ,

The licensee maintained that their design would provide diversity and would also eliminate concerns associated with common mode failures. The keep-fill piping between the condensing chamber and the CRD pumps for divisions 1 and 2 would include two diverse check valves (one being a lift check and the other being a spring-assisted check to close on zero flow) and a needle valve to i provide damping between the systems. The keep-fill piping would only affect the low pressure ECCS pumps as this is the area of concern of Bulletin 93-03.

The high pressure core spray system is designed to operate outside of the concerns of the Bulletin and the modification to divisions 3 and 4 would not make it susceptible to a loss-of-offsite power event or other failure in the CRD system.

PRA studies performed by the licensee demonstrated that the proposed design was advantageous over a design that would include a keep-fill system for all i four divisions.

Implementation of this modification is currently scheduled for the fourth refueling outage which is to begin on September 26, 1993. Final engineering e design and formal in-plant review will not be complete until the middle of f August and procurement of highly sensitive mechanical flow meters is not '

expected prior to late August. Citing the recent midwest floods, the difficulty Illinois Power is currently having transporting coal to its y [0j ,

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i 9308250361 930809 l ADDCK 0500 1

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Illinois Power Company August 9, 1993  ;

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fossil fuel facilities, and the urgent need to maintain the Clinton facility i on the southern Illinois grid, the licensee indicated that relief from the  :

recommended implementation date of the bulletin may be necessary if the [;

facility is brought to a cold shutdown prior to the planned outage.

Original signed by:  !

Frank L. Brush for

• Douglas V. Pickett, Senior Project Manager Project Directorate III-2 i Division of Reactor Projects III/IV/V ,

Office of Nuclear Reactor Regulation

Enclosures:

, I. Meeting Attendees

2. Handouts cc w/ enclosures:

See next page  ;

DISTRIBUTION '

- Enclosure I only: Enclosures 1 and 2: -

TMurley/FMiraglia Docket File f JPartlow NRC & Local PDRs JRoe PDIII-2 r/f .

JZwolinski DPickett  !

JDyer BClayton, RIII .

CMoore RGardner, RIII l OGC  !

. EJordan l AGody, Jr, ED0 i RJones, SRXB  !

! WLyon, SRXB JClifford i MPeck i

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0FC ;LA: P0llI-2 PM:PDIII-2 D:PDIII-2 i NAME biOOkE \I DPICKEfi[^ JDYER M DATE 65 / ( /93 s 67/ 1]93 23 /9_/93 / /93 / /93 / /93 COPY YES/Nd' [kES)NO [YEh)/NO YES/NO YES/NO YES/N0

Clinton Power Station Unit No. 1 l cc:  :

i Mr. J. S. Perry Illinois Department Senior Vice President of Nuclear Safety Clinton Power Station Office of Nuclear Facility Safety i Post Office Box 678 1035 Outer Park Drive Clinton, Illinois 61727 Springfield, Illinois 62704 j Mr. J. A. Miller Mr. J. W. Blattner Manager Nuclear Station Project Manager Engineering Department Sargent & Lundy Engineers j Clinton Power Station 55 East Monroe Street i Post Office Box 678 Chicago, Illinois 60603 Clinton, Illinois 61727 Mr. Richard F. Phares Sheldon Zabel, Esquire Director - Licensing '

Schiff, Hardin & Waite Clinton Power Station 7200 Sears Tower P. O. Box 678  !

233 Wacker Drive Mail Code V920 j Chicago, Illinois 60606 Clinton, Illinois 61727 Resident Inspector '

U.S. Nuclear Regulatory Commission RR#3, Box 229 A ,

Clinton, Illinois 61727 l

Mr. R. T. Hill Licensing Services Manager General Electric Company <

175 Curtner Avenue, M/C 481  !

San Jose, California 95125 l

Regional Administrator, Region III 799 Roosevelt Road, Building 4 Glen Ellyn, Illinois 60137 Chairman of DeWitt County c/o County Clerk's Office DeWitt County Courthouse Clinton, Illinois 61727 '

Mr. Robert Neumann Office of Public Counsel State of Illinois Center 100 W. Randolph, Suite 11-300 Chicago, Illinois 60601 l

ENCLOSURE 1 JULY 28. 1993 MEETING ATTENDEES NRC ILLIN0IS POWER Robert Jones Randy Langley Warren Lyon Wayne Shurlow James Dyer Pete Walberg Michael Peck Dick Phares James Clifford Douglas Pickett MEMBERS OF THE PUBLIC Scott Wingate, NUS Corporation l

ENCLOSURE 2 P@WER .

NRC/IP MEETING REACTOR WATER LEVEL MONITORING JULY 28,1993 Y

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1. R. Langley Director-Design & Analysis Engineering l W. L. Shurlow Supervising Specialist; Electrical Design

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P. E. Walberg Supervisor -IPE R. F. Phares Director-Licensing ILLINOIS POWER 1

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NRC/IP REACTOR LEVEL

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MONITORING MEETING '

3 AGENDA 1

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fNTRODUCTION R. F. Phares 1

1 CPS DESIGN J. R. Langley 1

i j DESIGN REVIEW W. L. Shurlow l

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l l RISK ASSESSMENT P. E. Walberg IMPLEMENTATION & TESTING W. L. Shurlow

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RISK ASSESSMENT (continued) .

. Case 2 - Reference Leg Fill - 4 Divisions

- Loss of off-site power scenario Probabilistic risk assessment (PRA) inputs

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RISK ASSESSMENT  ;

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