ML20082T054

Responds to Jf Streeter 831209 Request for Documentation of Actions Taken to Assure Adequacy of Station Distribution Sys Voltages.Procedures Issued,Historical Low Values Reviewed & Safety Evaluation Completed

ML20082T054
Person / Time
Site:	Prairie Island
Issue date:	12/08/1983
From:	Musolf D NORTHERN STATES POWER CO.
To:	Office of Nuclear Reactor Regulation
References
TAC-53312, TAC-53313, NUDOCS 8312150136
Download: ML20082T054 (59)

Text

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, o Northem States Power Company 414 Nico%t Man Minneapobs. Minnesota 55401 Telephone (612) 330 5500 1

December 8, 1983 1 Director Office of Nuclear Reactor Regulation i U S Nuclear Regulatory Commission Washington, DC 20555 PRAIRIE ISLAND NUCLEAR GENERATING PLANT Docket Nos. 50-282 License Nos. DPR-42 50-306 DPR-60 Procedures to Assure Adequacy of Station Distribution System Voltages On November 7 and 10, 1983 Mr John F Streeter, Chief, Engineering Branch #1, Region III, USNRC, visited the Prairie Island Nuclear Generating Plant as part of a special inspection into the circumstances surrounding an actuation of the degraded voltage protection logic at our Monticello Nuclear Generating Plant. Af ter his visit Mr Streeter requested that the following actions, related to prevention of a similar event at Prairie Island be documented:

a) Safety evaluation to support allowable ranges for substation voltages currently specified in procedures to maintain adequate safeguards bus voltages.

b) Procedures issued following the Monticello event to be upgraded to provide more operator guidance.

c) Review of historical low values in Prairie Island substation voltages.

A response by December 4, 1983 was requested by Mr Streeter.

A detailed safety evaluation has now been completed and reviewed by the Prairie Island Operations Committee to support currently specified allowable substatien voltages. A copy of this evaluation is available on site for inspection. Copies have also been provided to Mr Streeter and the Prairie Island Project Manager in the Division of Licensing for their use.

Our temporary operating procedure issued following the Monticello event has now been upgraded and approved by the Prairie Island Operations Committee.

A copy of this procedure is available on site for inspection. Copies have also been provided to Mr Streeter and the Prairie Island Project Manager in the Division of Licensing for their use.

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8312150136 831200 PDR ADOCK 05000282 i I

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NORTHERN STATES POWER COMPANY Dir, NRR *

-December 8, 1983 Page 2 Historical variations in the substation bus voltages have been reviewed.

The scope and this review was limit.ed to the current calendar year because of the short time allowed to complete our response. The results of this

. review are summarized in the attached table.

Please contact us if you have any questions related to the information we have provided.

be David Musolf Manager - Nuclear Suppor Services DMM/ dab c: J G Keppler NRC Resident Inspector NRR Project Manager, NRC G Charnoff Attachment

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