ML19326B409

Advises That B&W Analysis Shows Facility Can Be Safely Operated at 100% Full Power If Operator Acts within 10 Minutes During ECCS Small Break Loca.Permanent Fix Is Being Formulated

ML19326B409
Person / Time
Site:	Arkansas Nuclear
Issue date:	04/21/1978
From:	Rueter D ARKANSAS POWER & LIGHT CO.
To:	Reid R Office of Nuclear Reactor Regulation
Shared Package
ML19326B397	List: 05000313/LER-1978-009, Forwards LER 78-009/01T-0 05000313/LER-1978-009-01, /01T-0:on 780413,B&W Advised Util That Results of 0.04 Ft Squared RCS Pump Discharge Break Analysis Unacceptable.Caused by ECCS Analysis re-evaluation Performed for Newer B&W Plants ML19326B406 ML19326B409 ML19326B416
References
1-048-14, 1-48-14, NUDOCS 8004150773
Download: ML19326B409 (2)

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A A K A N S A S P O W E R & L I G H ~r C O M P A N Y A c. BCX 551

• UTTLe ACCK. A4GNSAS 722C3. (5C13 3714191 April 21, 1976 CCNALC A. AUETER CIAECTCA TECHNICAL ANO ENVIACNMENTAL SERVICES 1-048-14 Director of Nuclear Reactor Regulation ATTN:

Mr. R. W. Reid, Chief Operating Reactors Branch #4 U.

Nuclear segulatory Commission Washington, D. C.

20555

Subject:

Arkansas Nuclear One-Unit 1 Docket No. 50-313 License No. DPR-51 Reportable Occurrence No. 50-313/78-9 ECCS Small Break Analysis Interim Solution

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Gentlemen:

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As a result of further analysis, Babcock & Wilcox (B&W) has informed us that our interim solution to the subject item as proposed to you in our letter of April 17, 1978, is sufficient to allow operatien of ANO-1 at 100% rull Power (FP) provided that the operator action is taken within 10 minutes rather taan the 20 minutes mentioned in our earlier letter.

We have performed a test at ANO-1 in which we performed the operations required and timed the actions. The results indicate that an cperator can be dispatched and perform the actions required in less than 5 minutes, thus allowing 5 minutes for detection of the need for the action which is adequate for all scenarios.

We therefore conclude that ANO-1 can be safely operated at 100% FP while we formulate and implement a permanent fix. We have included the necessary actions in our emergency procedures at this time.

Your staff has also requested information on the power level at which we could oper. ate if wc took no action with regard to this event.

In response to enat request that power level would be 68% FP.

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l' 1-048-14 If you require further information at this time, please contact us.

l Very truly yours, t

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