ML19323F922

Forwards Safety Evaluation Supporting Mods to Power Supplies Providing Addl Assurance That Loss of Offsite Power Would Not Cause Diesel Generator Overload.Single Failures Causing Spurious Starting of Emergency Loads Should Be Addressed

ML19323F922
Person / Time
Site:	Point Beach
Issue date:	04/21/1980
From:	Schwencer A Office of Nuclear Reactor Regulation
To:	Burstein S WISCONSIN ELECTRIC POWER CO.
Shared Package
ML19323F923	List: ML19323F922 ML19323F924
References
TAC-42249, TAC-42250, NUDOCS 8005290644
Download: ML19323F922 (3)

Text

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NUCLEAR REGULATORY COMMISSION y.

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April 21, 1980 Cocket No.

/201 Mr. Sol Burstein Executive Vice President Wisconsin Electric Power Company 231 West Michigan Street Milwaukee, Wisconsin 53201

Dear Mr. Burstein:

We have reviewed your April 30, May 2, and May 21, 1973 submittals concerning the modifications to the design of the vital instrurent power supply for the Point Beach Nuclear Plant Units Nos.1 and 2.

These modifications were designed to correct an unacceptable arrangement of cower sources.

Based on our review, as presented in the enclosed safety evaluation, we have concluded that this problem is unique to Point Beach and the previous mod-ification to the power supplies provided additional assurance that a loss of offsite power would not cause the diesel generators to be overloaded and, therefore, was an acceptable interim fix. However, we do not believt that the modification provided protection against single failures causing the spurious starting of all emergency loads in both units.

(Such an event could result from a loss of offsite power and a LOCA in Unit 1, and a failure of the B battery or Unit 1 inverter under the present design.)

It i3 our understanding that additional modifications are being considered be your engineering group to correct this deficiency. We, therefore, request

.Jat you review the enclosed safety evaluation to er.sure that your modifi-cations will resolve the issues presented therein and inform us, within 30 days of your receipt of this letter, of your planned nodifications and your schedule to implement those modifications. Consideration should also be given to the changes which will be needed in the Technical Specifications.

800526 O

!!r. Sol Burstein Acril 21,1980 1

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Since we would like to have a timely resolution of this matter, we are available for a meeting if you so desire.

If you have any questions on this matter, please contact us.

Sincerely, f

.?b4 b"A

, ff A. Schwencer, Chief

[st Operating Reactors Eranch #1 Division of Operating Reactors

Enclosure:

Safety Evaluation cc w/ encl:

See next page

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Mr. Sol Burstein Wisconsin Electric Pcwer Company April 21, 1980 t

j cc: Mr. Bruce Churchill, Esquire Shaw, Pittman, Potts and Trowbridge j!

1800 M Street, N.W.

Washington, D. C.

20035 t

Document Department j

University of Wisconsin i

Stevens Point Library l

Stevens Point, Wisconsin 54481 Mr. Glenn A. Reed, Manager Naclear Operat'f ons 4

Wisconsin Electric Pcwer Company Point Beach Nuclear Plant 6610 Nuclear Road Two Rivers, Wisconsin 54241 i

Ms. Kathleen M. Falk i

General Counse)

Wisconsin's Environmental Decade 114 E. Mifflin Street Madison, Wisconsin 53703 4

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