ML20074A464

Notifies That Steam Generator Tube Rupture Analysis Addressed in Will Be Performed,Per SER Confirmatory Item 18 & Will Be Submitted by 830715

ML20074A464
Person / Time
Site:	05000470
Issue date:	05/10/1983
From:	Scherer A ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY
To:	Eisenhut D Office of Nuclear Reactor Regulation
References
LO-83-043, LO-83-43, NUDOCS 8305130081
Download: ML20074A464 (2)

Text

e. .

C-E Power Systems Tel. 203/688 1911 Combustion Engineenng Inc. Teler 99297 1000 Prospect Hill Road Windsor, Connecticut 06095 POWER M SYSTEMS Docket No.: STN 50-470-F May 10,1983 LD-83-043 Mr. Darrell G. Eisenhut, Director Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Subject:

Confirmatory Item 18, Steam Generator Tube Rupture Analysis

Reference:

Letter, C. O. Thomas to A. E. Scherer, dated April 26, 1983

Dear Mr. Eisenhut:

Discussions have been held between Combustion Engineering (C-E) and members of the Reactor Systems Branch (RSB) and the Accident Evaluation Branch (AEB) to determine the Staff requirements for a re-analysis of the steem generator tube rupture (SGTR) event for CESSAR-F. The reference letter documents the Staff requirements for the resolution of Confirmatory Item 18.

As a result, we shall perform the SGTR analysis assuming offsite power is unavailable subsequent to reactor trip. Per the Standard Review Plan, operator actions will be considered to assure that the most severe case has been considered. Since the currently docketed analysis was submitted prior to the final formulation of CEN-152, " Combustion Engineering's Emergency Procedure Guidelines", the guidelines were not considered for operator actions. Our re-analysis, however, will take into account the guidelines per CEN-152. It will be assumed that the operator uses the atmospheric dump valves (ADV's),

subsequent to an appropriate time after reactor trip, to facilitate the primary system depressurization and cooldown to a set of conditions which would not challenge the main steam safety valves; and, then the affected steam generator would be isolated. As required by the reference letter, however, we i shall assume that an ADV on the affected steam generator is stuck open at the operating position which would result in the fastest cooldown rate allowed.

Credit will be taken for operator action ten (10) minutes after it would become apparent that an ADV on the affected steam generator is stuck open. It will be i assumed that the operator closes a block valve upstream from the stuck open ADV I

and thus limits the release. Cycling of the remaining ADV's during the i analysis will be allowed should it become necessary to prevent overfilling of the steam generators. The calculated doses shall be within the guidelines of 10 CFR Part 100.

8305130081 830510 PDR ADOCK 05000407 E PDR b[

.mo. .

Mr. Darrell G. Eisenhut LD-83-043 May 10,1983 Page 2

! We are proceeding with the above analysis and will submit the revised CESSAR-F analysis by July 15, 1983. If there are any questions or comments on our intentions, or if the above is not in accordance with the Staff's requirements, please notify us immediately. Please feel free to contact myself or Mr. G. A.

Davis of my staff at (203) 688-1911, extension 2803.

Very truly yours, COMBUSTION ENGINEERING, INC.

f24 A. E. cherer Director Nuclear Licensing AES:las F72086 cc: Gary Meyer (Project Manager / USNRC) i l

l

. - . .