ML20101B569

Suppls 910724 Response to Edsfi Insp Repts 50-254/91-11 & 50-265/91-07.Corrective Actions:Project Plan Developed to Determine Exact Scope,Schedule & Resource Requirements to Perform EDG Dynamic Analysis

ML20101B569
Person / Time
Site:	Quad Cities
Issue date:	06/01/1992
From:	Kovach T COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9206040198
Download: ML20101B569 (2)

Text

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Commonwealth Edison 1 C 1400 Opus Place O'O Downers Grove. Illinois 60515 June 1,1992 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 4

Attention: Document Control Desk

Subject:

Ouad Cities Nuclear Power Station Units 1 and 2 4

Supplementai Response to Electrical Distribution System Functional Inspection (EDSFI) Report 50-254/91011;50-265/91007

biflC_QQche1Nosm50:254md10-265 i

References:

(a) H.J. Miller letter dated June 24,1991 4

transmitting NRC Inspection Report 50-254/91011;50-265/91007 (b) T.J. Kovach letter to NRC dated July 24,1991 transmitting CECO's response to IR 50-254/91011; 50-265/91007 (c) P.L. Piet letter to D. Butler dated April 27,1992

transmitting Dresden ECCS Full Flow Functional Test I

(d) H.J. Miller letter to Cordell Reed dated May 8,1992

EDG Response acknowledgement 4

Reference (b) provided the Commonwealth Edison Company (CECO) response to the EDSFI report of Reference (a). As a result of a discussion between Mr. David Butler, NRC Region ill, and CECO, the actions to be taken to address Unresolved item 254/910011-03; 265/91007-03 were revised. Attachment A provides the revised CECO

response and current status to the subject Unresolved item.

i If your staff has any c uestions or comments concerning this letter, please contact Jim Watson, Compliance Engineer, at (708) 515-7205.

Sincerely, l __

g60Q QQh T.J. Kovach l G PDR Nuclear L,i censing Manager I

Attachments 9 0f cc: A.B. Davis, Regional Administrator- Region 111 ' I

D. Butler, Region til

• T. Taylor, Senior Resident inspector L. Olshan, Project Manager- NRR

o ATTACHMENT A UNRESOLVED ITEM 254/91011-03;265/91007-03 During the EDSFl Inspection, the team identified a number of weaknesses with calculation No. 7318-33-19-3, dated October 5,1990, in regard to the capability of the Diesel Generator (DG) to meet load sequencing and totalload capacity requirements.

Also, it was unclear how a designated design reviewer could determine calculation acceptability since key acceptance criteria of the calculation and DG loading ca 3 ability criteria were not stated in the body of the calculation. Pending further analysis ay the licensee and subsequent NRC review, this item was considered unresolved.

CECO Response:

During the EDSFI inspection at Quad Cities Station, the NRC team members identified weaknesses with the Emergency Diesel Generator loading calculations.

Originally, CECO committed to revise the Diesel Generator calculations by the end of the first quarter of 1992.

On February 19,1992, Chris Grier (CECO Engineering) and Mr. David Butler (NRC Region lil) discussed improved alternative actions to resoive thic issus. At that time, Mr. Butler acknowledged the revised actions which were:

1. Complete an evaluation of Dresden's Diesel Generators Automat lc load Sequencing for Units 2 and 3 (DG 2,3, and 2/3). This evaluation shows the relat'onship between Emergency Diesel Generator Loading Sequence and the DBA LOCA Accident Scenario. Resuts of the evaluation shows the diesel generator response to the automatic load sequence adequately characterizes the DG resaonse during an actual DBA. Th' report was sent to Mr. Butler in the letter o1 Reference (c) and acknowledged in the letter of Reference (d).

CECO has reviewed this evaluation and verified that it is applicable to Quad Cities Station.

2. Prepare a project plan to determine the exact scope, schedule, and recource requirements to perform a EDG dynamic analysis for Dresden Station (also applicable to Quad Cities Station). The objectivo of inis report is to present a generic methodology for performing dynamic DG loading analysis at CECO nuclear power plants. .

The above mentioned reports have been completed. These reports resolve the NRC concerns on the EDG loading calculations and the ability of the EDG's to handle the required emergency electricalloads at Dresden and Quad Cities Stations.

, ZNLD/1814/2 1

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