ML18127A545

Reference to Telephone Call of 5/16/1978, Enclosed Is Additional Information from Florida Power & Light Concerning Interruption of Off-Site Power to St. Lucie Plant on 5/14/1978

ML18127A545
Person / Time
Site:	Saint Lucie
Issue date:	05/17/1978
From:	Reis H Florida Power & Light Co, Lowenstein, Newman, Reis & Axelrad
To:	Paton W NRC/OGC
References
Download: ML18127A545 (5)

Text

LAW OFFICES LOWE'NSTEIN, NEWi~IAN, HEIS 8C AXHLRAD IO25 CONNECTICUT AVENUE, N. W.

ROSCRT LOWCNSTCIN WASHINGTON, O. C. 2OO36 JACK R. NEWMAN HAROLD F. RCIS MAVRICC AXCLRAD 202 862-8400 KATHLECN H, SHCA J. A SOVKNIGHTI JR.

MICHAEL A, OAVSCR ALSERT V. CARR, JR, ROSCRT H CVLP

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WILLIAMJ. FRANKI.IN I'RCOCRIC S. GRAY LINDA L. HODGC JONATHAN R, SHCINCR JOCL S. WIGHT (AOH, CAL1D William D. Paton, Esq.

Counsel for NRC Regulatory Staff U.S. Nuclear Regulatory Commission Washington, DC 20555 Re: In the Matter of Florida Power and Light Company (St. Lucie Nuclear Power Plant, Unit 2) Docket No. 50-389

Dear Mr. Paton:

This is with further reference to my telephone call to you yesterday morning, May 16, 1978. I then advised you that, on Sunday morning, May 14, 1978, off-site power to the St. Lucie nuclear power plant was inter-rupted and that the appropriate reports to the Commission would be made. I also told you that I would obtain from Florida Power 6 Light Company additional information concerning the outage and supply them promptly. I have now received such further information and am supplying it in the enclosure to this letter.

Sincerely, Harold F. Reis HFR/jm Enclosure cc (w/enc.): See attached service list

UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION Before the Atomic Safet and Licensing Appeal Board In the Matter of FLORIDA POWER 6 LIGHT COMPANY )

Docket No. 50-389 (St. Lucie Nuclear Power Plant, Unit No. 2)

CERTIFICATE OF SERVICE I hereby certify that copies of the attached letter to William D. Paton, Esp., dated May 17, 1978, together with the enclosure to that letter have been mailed the 17th day of May, 1978, to the persons shown on the attached service list by deposit in the United States mail, properly stamped and addressed.

AROLD F. REIS Lowenstein, Newman, Reis 6 Axelrad 1025 Connecticut Avenue, NW Washington, DC 20036 Telephone: (202) 862-8400 Date: May 17, 1978

UNiTED STATES OF A>4ERiCA NUCLEAR REGULATORY COMMISSION Before the Atomic Safety and Licens'ng Apaeal Boa d, in the Matter of FLORiDA POWER & LiGHT COAPAvVv ) Docket No. 50-389 (S . ucle Nuclea Powe>> Plan )

Uni" 2)

SERViCE LiST Mr. C. R. Stephens Supervisor, Docketing and Service Section Off'ce of the Secretary of the Commission Vuclear Regulatorv Commiss'n Washington, D. C. 20555 M'chael C. Far=ar, Escuire Chairman Atomic Safetr & Licens'ng Appeal Board Nuclear Regulatory Commission Wash'ngton, D. C. 20555 Dr. W. Reed Johnson A"omic Safety & Licensing Appeal Board Nuclear Regulatory Comm'ssion Wash'ngton, D. C. 20555 Richard S. Salzman, Esauire Atomic Safetv & Licensing Appeal Board Nuclear Regulatory Commission Wasnington, D. C. 20555 Alan S. Rosenthal, Escuire Chairman Atom' S af ety & Licens 'g Vuclear Regu'torv Commission Appeal Panel Wash.'rqton, D. C. 20555 Edward Luton, Escui"e Chairman Atomic Safetv & Licensing Boa " Panel Nucl a" Regula ory Commission Washington, D. C. 20555

Michael Glaser, Escuire Alt mat,e Cha'rman Atom'c Safetv and Licens'ng Board 1150 17th St= et, N. N.

Nashirgton, D. C. 20036 Dr. Harvin N. Mann Technical Advisor Atomic Safetv Z Licensing Board Nuclear Regulatory Commiss'on Washington, D. C. 20555 Dr. David L. Het=ick P=ofessor of Nuclear Erg'nee incr Un'versity o" Arizona Tucson, Arizor a 85721 Dr. Frank F. Pooper Cha'rman, Resource Ecology Program School o= Natu al Resources Univers.tv of iMich'gan Ann Ar'"or, .Iichigan 43104

&Ir. Angelo Giamhusso Deouty Director for Reactor Projects Nucle r Regulatorv Commission Nash'rg"or., D. C. 20555 William D. Paton, Esauire Counsel for VRC Regulatorv Sta=.

Nuclear Regul to y Commission Nasnington, D. C. 20555 Pie Harold Hodder, Esauire Hartin 1130 N. E. 86 Street Miami, Florida 33138 Norman A. Coll, Esp.

Steel, Hector 6 Davis Southeast First National Bank Building Miami, FL 33131 Local Pualic Document Room Indian River Junior College Library 3209 Vi "ginia Avenue Ft. "ce, F lorida 33450 Nil1 iam J . t Olms cad, E scuir e U. S. Nuclear Regulatory Commiss ion Nash'ngton, D. C. 20555 W

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ENCLOSURE On Sunday morning, May 14, 1978, at approximately 7:45 a.m.,

offsite power to St. Lucie Nuclear Power Plant was interrupted due to a combination of two factors: a switching error at the Pratt 6 Whitney Substation and a wiring error on the transformer at the Midway Station. Approximately 100 MW's out of a total load of approximately 3500 MW's were lost for 8 minutes.

Midway Substation is fed from the south by two major high voltage lines coming from Ranch Substation. One of these lines goes through the Pratt 6 Whitney Substation where the switching for maintenance purposes was taking place. Midway Substation also has two lines coming into it from the north from Malabar Substation, as well as three other lower voltage (one 69KV, two 138KV) lines, When the switching error occurred at the Pratt S Whitney Substation.a flashover occurred and both lines from Ranch to Midway were interrupted. Because of the wiring error (reversal of polarity in current transformers) in the Midway Substation, the protective relay system interpreted this incident as a fault on the Malabar lines and interrupted those lines. The three lower voltage lines opened on the power surges and the result was a complete loss of power to the Midway Substation, thereby interrupting the power supply to St. Lucie Unit 1, which was down for refueling. The diesel generators at St. Lucie 1 immediately started, thereby providing emergency power to the unit. This interruption did not in any way jeopardize plant system or safety.

Power was restored to Midway Substation in approximately 8 minutes and complete power was restored to all lines in approximately 15 minutes. The wiring error has been corrected and the cause of the switching error has been determined and resolved.