Meeting #1377, 28 May 1958: om pepee . OS a Additional personnel in attendence at this meeting included Bradbury, Brown, Graves, Sewel, and Teller. The lengthy discussion in which / these gentlemen participated on weapons test limitations and the ' possibility and effects of a moratorium are classified SECRET and a copy will be obtained to keep in our classified files. The afternoon session of this 28 May meeting addressed the possible additiongt of shots to Hardtack. Libbey had calculated that approximately 8 megatons of fission yield would be contributed to the atmosphere by those shots already approved and the discussion of the additional fallout contribution of the new shots took place. The Commissioners were addressing whether to request the additional shots for the President's authorization and what to present as the request for Project Millrace. A couple of the points brought up were: That the President was very concerned about the number of weapons and the amountoffallout being contributed by Hardtack; That, in.view of the present intérnational climate with respect to weapons testing and a possible moratorium, . the President might not question inclusion of additional shots since Hardtack might be the last test series. Apparently the total estimated fission yield with the new shots included in the Hardtack would be 8.4 megatons. The Commission approved for preparation and later revision possibly a letter to the President requesting the complction of Hardtack with two additional and one contingency shot. Alsu it would request that Millrace be approved and, if Millrace were not approved, then Hardtack would require one additional atmospheric and a l-point | Uo”