NRC Generic Letter 81-16, NUREG-0737 Item I.C.1 SER on Abnormal Transient Operating Guidelines (ATOG)

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WASHINGTON, D. C. 20555

June 1, 1981

TO ALL B&W LICENSEES (Except Arkansas Nuclear One, Unit One)

Gentlemen:

SUBJECT: NUREG-0737, ITEM I.C.1, ABNORMAL TRANSIENT OPERATOR GUIDELINES (ATOG) (Generic Letter No. 81-16.)

The staff has completed a preliminary review of the ATOG prepared for Arkansas Nuclear One Unit One and submitted as generic guidelines in response to NUREG-0737, Clarification of TMI Action Plan Requirements, Item I.C.1. We have identified the following deficiencies in areas that were identified in NUREG-0737, but are not addressed by the ATOG submittal:

1. The bases for the consideration of multiple and consequential failures is not provided. The sequence-of-event diagrams are not complete (i.e.,

ATWS following an initiating event).

2. Supporting analyses for multiple failures are not presented for all cases. The description of the computer programs used to analyze the events is not provided.

3. Operator errors of omission or commission are not addressed.

4. The following multiple failure events are not addressed:

(a) SG tube rupture in more than one steam generator;

(b) Failure of the high-pressure reactor coolant makeup system;

(c) ATWS following an initiating event (with or without a turbine trip); and

(d) Failure of main and auxiliary feedwater with partial or complete loss of HPI.

5. The transition from emergency procedures into an adequate core cooling (ICC) procedure is not developed or included. (We understand that B&W is incorporating ICC into the ATOG program for some future submittal.)

Since you have referenced this report as applicable to your facility, please advise us within 30 days of your receipt of this letter of your schedule for response to these items and the impact this will have on your schedule for implementing a program of emergency operating procedures that comply with the requirements of NUREG-0737, Item I.C.1.

.

All B&W Licensees Except -2-

ANO-1

Since the responses required by this letter affect fewer than 10 licensees and are required to obtain a benefit, they are not subject to Office of Management and Budget clearance as required by P.L. 96- 511.

Sincerely,

Thomas M. Novak, Assistant Director for Operating Reactors Division of Licensing