Because no other amphibious aircraft were available, the same UF-1 and crew returned after a brief lunch at Kwajalein, where the cargo originally meant for Rongerik was offloaded. The UF-1 returned to Kwajalein at about 1330 with the remaining 20 men from Rongerik (Reference 84). A conference was held at 1330 at which the task force radsafe officer, the task force and task group commanders, and the Scientific Director reviewed what was known of the fallout situation. A decision had been made, albeit at the local level, to evacuate the U.S. personnel on Rongerik, and now the other atolls in the vicinity had to be considered. As part of the offsite fallout monitoring program of the AEC Health and Safety Laboratory, postshot flights were conducted over all the Marshalls. Several patterns, designated Able, Baker and Charlie, were flown by VP-29. Able, a flight over the northern Marshalls, was underway on 2 March. Before the conference was over, an inflight report from flight Able indicated 1.350 R/hr at 1340, 2 March, extrapolated to ground level at Rongelap Island, 0.400 R/hr at 1328 at Ailinginae, and 0.001 R/hr at 1300 at Wotho. It was decided that evacuation of Rongelap was necessary and that other islands likely to be involved would be determined from the readings of the remaining portion of the flight Able pattern (Reference 26). Accordingly, the destroyer Philip left for Rongelap immediately. In- structions were issued to dispatch an Air Force SA-16 amphibian flight with two radsafe monitors to check surface conditions at Rongelap before dark. The destroyer was directed to be off Rongelap ready to start evacu- ation at dawn the following day. A Trust Territory representative and an interpreter were requested to move by PBM seaplane from Kwajalein to arrive at Rongelap at the same time. The SA-16 flight was set up and the two monitors were especially briefed to make readings at waist height, to use several meters of the same type for comparison, and to use different types for cross-checking. 227