ML20084P388

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Responds to Request for Addl Info on Extension of Schedule Completion Dates,Confirming Commitments for Suppl 1 to NUREG-0737,identified in 840221 Order.Extension Date for Submittal of Summary Rept to Reg Guide 1.97 Requested
ML20084P388
Person / Time
Site: Davis Besse Cleveland Electric icon.png
Issue date: 05/10/1984
From: Crouse R
TOLEDO EDISON CO.
To: Eisenhut D
Office of Nuclear Reactor Regulation
References
RTR-NUREG-0737, RTR-NUREG-737 1047, TAC-54497, NUDOCS 8405180189
Download: ML20084P388 (3)


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s TOLEDO Docket No. 50-346 EDISON License No. NPF-3 RicHAno P. CROUSE vc. presem Serial No. 1047 ***'

I4191259-5221 May 10, 1984 Mr. Darrell G. Eisenhut, Director Division of Licensing Office of Nuclear Reactor Regulation United States Nuclear Regulatory Commission Washington, D.C. 20555

Dear Mr. Eisenhut:

This is in response to a verbal request from Mr. A.-W. DeAgazio, Davis-Besse Project Manager, concerning additional information on our extension of schedule completion dates, confirming Toledo Edison's commitments for Supplement 1 to NUREG-0737, as identified in the Order dated February 21, 1984 (Log No. 1456). Toledo Edison has requested an extension on the submittal date for the summary report for Regulatory Guide 1.97, Detailed Control Room Design Review (DCRDR), from April 15, to June 30, 1984, for the Davis-Besse Nuclear Power Station Unit No. 1.

Our review of Reg Guide 1.97 has been ongoing in conjunction with the B&W Owner's Group Task Force on Reg Guide 1.97. The Owner's Group Task Force's last meeting was held on April 5 - 6, 1984, to discuss the group report. The purpose of the Task Force is to formulate and fully justify a generic position on Reg Guide 1.97 for B&W NSSS plants. The Task Force has identified a need for evaluation of certain variables in the context of the B&W plants. The Task Force desired that for each of the forty-two (42) selected Reg Guide 1.97 variables, an evaluation be performed to:

a. Determine the significance of the variable to monitoring and manage-ment of design basis accident for a B&W plant.
b. Define the qualification criteria considered necessary to support the accident monitoring function,
c. Assess whether the typically supplied instrumentation is adequate for the required monitoring function.

The next scheduled meeting of the B&W Owner's Group Task Force is in June.

At the Owner's Group meeting in April, the report was reviewed and the need was established for additional input by the member utilities. Also, at that meeting Toledo Edison identified iteme for our submittal that require clarification, technical basis, and justification of exceptions.

This review is ongoing at the present time. After Toledo Edison's report is completed, it will be reviewed by appropriate departments within the THE TOLEDO EDISON COMPANY EOISON PLAZA 300 MADISON AVENUE TOLEDO. OHIO 43652 8405180189 840510 g9 ponAnocnosooop4)

Dsckst Ns. 50-346 Lictn a No. NPF-3 i Serial No. 1047 May 10, 1984 Page 2 Nuclear Mission as to the effect this will have on them and the complete-ness of the document.

The DCRDR Program Plan submitted on June 15, 1983, (Serial 958), indicated  !

that the systems function review and task analysis were to be based on

' hypothesized event sequences following the postulated occurrence of each ,

of the six initiating events. These six initiating events are considered in the Davis-Besse Abnormal Transient Operating Guidelines (ATOG), and are as follows:

1. Loss of Main Feedwater
2. Excessive Feedwater
3. Loss of Offsite Power
4. Small LOCA ,
5. Steam Line Break
6. Steam Generator Tube Rupture During the course of the DCRDR project, the review team became concerned about the completeness in addressing emergency operations in the Control Room from a systems function review and task analysis that is based solely ,

on the above mentioned selected set of initiating events. Furthermore, ,

the systems review and task analysis approach.that is based on hypothe-sized event sequences following the postulated occurrence of an initiating event is necessarily event oriented as opposed to being function oriented.

In order to adequately address the above concerns, the scope of the Toledo Edison DCRDR effort has been expanded to include a comprehensive systems review and task analysis that is based on the symptom / function-oriented Emergency Operating Procedures (EOP's). These procedures are currently in the final stages of the verification and validation process. However, it is recognized that such an approach has the potential for co-validation and circular logic, in the sense that the systems function review and task analysis would be internally consistent, since the symptom oriented E0P's are based on the existing controls and displays in the Control Room at Davis-Besse.

In order to avert the potential problems of co-validation and circular logic, the scope of the DCRDR project is being expanded further to include a systems function review that is independent of the symptom-oriented E0P's. This additional systems function review is based on the safety sequence diagrams originally prepared for the ATOG effort. Information requirements in the Control Room to support the function and system requirements are being established without consideration of the avail-ability and suitability of information from the existing controls and displays in the Control Room at Davis-Besse. These requirements will then

.be compared to the results of the system function review and task analysis based on the symptom-oriented E0P's. The effort will provide an indepen-dent assessment of the system function review and task analysis based on ,

the symptom-oriented E0P's to assure that it was not unduly biased by a prior knowledge of the Control Room instrumentation and controls.

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Drck'et No. 50-346 Lican;a Ns.' NPF-3 Serial No. 1047 May:10, 1984 Page 3 P

In an effort to provide a comprehensive report on Reg Guide 1.97 and DCRDR, Toledo Edison will review the reports against each other. This type of review has taken place with the Fire Protection Program in February for its effect on Reg Guide 1.97 for which several items were addressed. This review is a necessary process, as the Reg Guide 1.97 and DCRDR reports are being prepared by different groups within Toledo Edison.

Any change proposed by either group could have a direct relationship on the other group efforts. The comparison of proposed changes would maxi-mize the allocation of Toledo Edison's resources and prevent duplication of effort.. The documents submitted will provide a greater cohesive relationship between them and compliance with the requirements.

l Very truly yours, b M. ,

'RPC: GAB:JRL:lah cc: DB-1 NRC Resident Inspector e

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