ML19326A242
| ML19326A242 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 08/05/1970 |
| From: | Tedesco R US ATOMIC ENERGY COMMISSION (AEC) |
| To: | Morris P US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 8002030100 | |
| Download: ML19326A242 (2) | |
Text
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Ae-AUG 5 1970 Peter A. Morris, Director, Division of Reactor Licensing
@nal signed by Roger S. Boyd, Assistant Director for Boiling Water N b s, g o T
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ACRS SUBCOMMITTEE MEETING ON THE DAVIS-BESSE PROJECT - PRDfARY AND SECONDARY SYSTEM FAILURE - DOCKET NO. 50-346 At the Subcommittee meeting held on August 4,1970, Bechtel (the A&E) indicated that failure of the secondary system was considered in its evaluation of the containment design following a LOCA. The acceptance criterion indicated by Bechtel was that the resulting pressure should not exceed the contairunent design pressure. Bechtel indicated that it would be acceptable to them if the resulting pressure even exceeded by some small margin the proposed design pressure.
I noted that up to now we had not been requested to review applications on the basis of a combined failure of the primary and secondary system.
All applications contained the design basis considering a rupture of the primary system only.
During our review of the Davis-Besse project, we noted that the appli-cant did not include design provisions to preclude failure of the secondary system due to a primary system rupture,and in our ACRS report we stated our position that suitable design provision be made to preclude this event.
Such provisions would include either a redesign of the containment or installation of suitable restraints on the primary piping to prevent failure of the secondary system.
Bechtel indicated that they only considered possible pressure incre-mental changes due to additicu of energy from the secondary system.
The consequences of direct fission product leakage, interaction with ECCS, possible effects of boron dilution due to mixing of the secen-dary system coolant with the primary system coolant were not evaluated.
l Secause of the questions raised during the meeting, Dr. Siess (Sub-committee chairman) stated that further discussions would be held at the full Committee meeting next week. In particular, he stated that the staff should be prepared to discuss how these matters have been treated on other plants. His concern is that perhaps we have not considered the effects of failure of the secondary system on plants that did not have suitable protection.
It certainly appears that a ME omer >..
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Ibrm AEC-318 (Rev. S-53) 3.1 sovtanmort renimG crMct. tus-o-w4-ese 8002030\\00 j
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0 meeting should be held with DRS to discuss this matter as well as possible action regarding past reviews so that we can discuss the matter with the full Conanittee at the August meeting. I believe that it would be appropriate for DRL and DRS to review the history of past plants as well as the philosophy and policy on sizing of containments.
Original signed by Robert L. Tedesco R. L. Tedesco, Chief BWR Branch No. 2, DRL cc:
E. G. Case
- 7. Schroeder R. DeYoung R. R. Maccary M. Rosen Branch Chiefs, DRL 3 ranch Chiefs, DRS
- 3. Grimes H. Spectar R. R. Powell Distribution:
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Form AEC.318 (Rev. b53) u.s.soutenuen mutme omaases-o-as.-see