these locations more precisely and also lists a numberof other successive positions occupied by each ship between the times of arrival and cessation of fallout. From the tabulated data, the approximate courses of the ships during their sampling intervals may be reconstructed. The given coordinates represent Loran fixes, however, and cannot be considered accurate to better than +500 yards. Further, the ships did not always proceed from one point to another with constant velocity, and an uncertainty of +1,000 yards should be applied to any intermediate position calculated by assuming uniform motion ina straight line between points. The ships were directed to the initial positions listed in Table 2.4 by messages from the Program 2 Control Center (see Section 2.4.1); but once fallout began to arrive, each ship performed a fixed maneuver which led to the remaining positions. This maneuver, which for Shots Cherokee and Zuni consisted of moving into the surface wind at the minimum speed (< 3 knots) necessary to maintain headway, was a compromise between several requirements: the desirability of remaining in the same location with respect to the surface of the earth during the falloutcollection period, and yet avoiding nonuniform sampling conditions; the importance of preventing sample contamination by washdown water— particularly on the forward part of the YAG 40 where the SIC was located; and the necessity of keeping the oceanographic probe (SIO-P) away from the ship. It was found, however, that the ships tended to depart too far from their initial locations when surface winds were light; and this maneuver was modified for the remaining shots to include a figure eight with its long axis (<2 nautical miles) normal to the wind, should a distance of 10 nautical miles be exceeded. The YAG 40 and LST 611 ordinarily left their sampling sites soon after the cessation of fallout and returned to Eniwetok by the shortest route. The YAG 39, on the other hand, after being relieved long enough to unload samples at Bikini to the vessel, Horizon (Scripps Institution of Oceanography), remained in position for an additional day to conduct water-~sampling operations before returning to Eniwetok. 2.4 OPERATIONS 2.4.1 Logistic. Overall project operations were divided into several parts with one or more: teams and a separate director assigned to each. Both between shots and during the critical D—3 to D+3 period, the teams functioned as the basic organizational units. In general, instrument maintenance was accomplished during the interim periods, instrument arming between D—3 and D-1, and sample recovery and processing from D-day to D+ 3. Control-center operations took place in the Program 2 Control Center aboard the command Ship, USS Estes. This team, which consisted of three persons headed by the project officer, constructed probable fallout patterns based on meteorological information obtained from Task Force 7 and made successive corrections to the patterns as later information became available. The team also directed the movements of the project ships and performed the calculations required to reduce and interpret early data communicated from them. . Ship operations featured the use of the YAG 40, YAG 39, and LST 611 as sampling stations. These ships were positioned in the predicted fallout zone before the arrival of fallout and reMained there until after its cessation. Each ship was manned by a minimum crew and carried One project team of three or four members who readied the major array instruments, operated them during fallout, and recovered and packed the collected samples for unloading at the sample~ distribution center on Site Elmer. Water sampling, however, was accomplished by separate twoman teams aboard the YAG’s, and early-sample measurements were performed by a team of six Persons in the YAG 40 laboratory. ; Bikini operations included the maintenance, arming, and recovery of samples from all project stations in the atoll area. Because every station had to operate automatically during fallout and samples had to be recovered at relatively early times, three teams of four or five men each Were required. The barge team was responsible for the major sampling arrays on the YFNB 13, YFNB 29, and Site How, as well as for the special sampling facility located on the latter. The raft team was responsible for the minor sampling arrays on the rafts and atoll islands, and the 25