Further, although wind patterns could develep in whieh mid-level resultant vindslay im the aceeptable sector, the vector summation of these winds must have sufficient southerly comporent to carry the bulk of the mid-lowe] detris far encugh north of Ground Zero eo that the crosewind ond upwind epreed of comtemination over the atoll does act overlap the camp sites. 4 not wicomen condition appeared at BYIWETOX several tines during tho cperntion in whic the midelevals to afout 40,000 feet had southerly wind with westorlics above, euch that the vector summation of ali the levals placod the bulk of con- tamination within fifty miles to the north of Ground Zero. The proximity of the eanmp sites to the fall-cut from weh patterns, plus the added me certainty of ite stability (i.e. the uncertainty of the scutherlies holding favorable) we the prine factor in not aecepting such « pattern for BITWETK. Taxis problen was rolatively insigrificant for Biking “toll shots, atoll comtarmination not being a problem due to eompletely ship-based operations at that atell. ‘The only “real estate” risk taken on BIKINI shots wisthat on the airstrip and on stations to ba re-estivated for ancther shot, Vortunately, the forner risk turned out insignificant; the lattor risk ws overcons through efficient control of ro-untry rosovery and work parties. La a generel statexenh, it would appear that the weight given to yield as 0 factor in the decision and cAhcise of « shot atoll, should bo revised. It would now appear that barge shots with yields and vdinds on the order of ROMEO, ONION om YiNKRS could be detonated in the vicinity of MIKE crator at SHIWBTOK without undue risk from fall-out. It wuld eppsar reasonable however, to neintain an evacuation capability in the event sueh becare nesessary. 65 }