LD-84-042, Forwards Items for Updating When SER Generated to Close Out Remaining Issues.Items Include Steam Generator Tube Rupture,Radiological Consequences of DBA & Shutdown Cooling (RHR) Sys

Forwards Items for Updating When SER Generated to Close Out Remaining Issues.Items Include Steam Generator Tube Rupture,Radiological Consequences of DBA & Shutdown Cooling (RHR) Sys

ML20094J105
Person / Time
Site:	05000470
Issue date:	08/03/1984
From:	Scherer A ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY
To:	Eisenhut D Office of Nuclear Reactor Regulation
References
LD-84-042, LD-84-42, NUDOCS 8408140230
Download: ML20094J105 (2)

Text

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C-E Power Systems Tel. 203/6881911 Combustion Engineering. Inc.

1000 Prospect Hill Road Telex: 99297 CCf O

Windsor, Connecticut 06095 k

POWER M SYSTEMS Docket No.: STN-50-470F August 3, 1984 LD-84-042

.Mr. Darrell G. Eisenhut, Director Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Subject:

Safety Evaluation Report Suggested Changes

Dear Mr. Eisenhut:

During work with the CESSAR Safety Evaluation Report (SER) and its supplements, four (4) Items have been identified which we suggest should be be updated.

These items are identified in the enclosure to this letter along with justification for each change. Combustion Engineering suggests that these items be updated when the SER is generated to close out the remaining issues on CESSAR.

If you have any questions or comments, please feel free to call me or Mr. T. J. Collier of my staff at (203) 285-5215.

Very truly yours, COMBUSTION ENGINEERING, INC.

A.E[Scherer ~

Director Nuclear Licensing AES:las Enclosure cc: K. Eccleston, Project Manager, USNRC 8408140230 840803 Go*3 PDR ADOCK 05000470 I a E PDR D

. e LD-84-042 Enclosure 6

SER SUGGESTED CHANGES SUPPLEMENT #2 Section 15.3.7 Steam Generator Tube Rupture The SER states, "We require C-E to provide an interface requirement on the need to classify the block valves upstream of the ADVs as safety-related and, therefore, required to be designed to safety grade requirements consistent with the assumptions in the SGTR analysis". As a result of the re-analysis, required-by the NRC, C-E added an interface requirement for ADV block valves to be installed. Failure of a block valve would constitute a second failure which is beyond the basis for licensing analysis. Thus, C-E believes that the r_equirement to make the ADV block valves safety grade should be deleted.

In addition, the SER description of the re-analysis states, " 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". Actually, however, in the revised CESSAR analysis, credit was taken for operator action thirty (30) minutes after realization that the ADV was stuck open. C-E believes, therefore, that the ten (10) minutes in the SER should be changed to-thirty

-(30) minutes.

SUPPLEMENT #2: Section 15.4 Radiological Consequences of Design Basis Accidents Item-(2) of the site-related interface requirements for CESSAR reference plants states that Steam-Generator tube leakage be 0.1 gpm primary to secondary. This value was based on the Reactor Coolant Pump locked rotor / shaft seizure analysis originally submitted with CESSAR and was required to show acceptable off-site doses. : Subsequent analyses evaluated in SER Supplement #2 have shown acceptable consequences for steam generator. tube leakage of 1.0 gpm.

l Therefore, the ma,ximum steam generator tube leakage should be changed tc 1.0 -

gpm, consistent 'with analyses for worst case assumptions used ,in design basis.

accidents.

SUPPLEMENT-#1 Se.: tion 5.4.3 Shutdown Cooling (Residual Heat Removal) System

. Pages 5-2 and 5-3 provide a discussion of the applicability of Power Operated Relief Valves (PORVs) to C-E plants. The discussion is-concluded with the statement, "Should the NRC decide that design or procedural changes are

. necessary, C-E will be required to implement them for CESSAR". Since the NRC has deferred the decision.on P0RVs to the resolution of Unresolved Safety Issue

- A-45, C-E believes that this should be reflected in the SER.-

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