Theavailable radiological data for MOLALAandnearby ships on 1 Marchare air sample activities rather than topside intensities. As only partial measurement of the airborne concentrationsof radioactive fallout are available during fallout deposition on MOLALA,the more complete measurements obtained onboard YAG-40 (1,550 feet behind) are used to estimate the environment on MOLALA. Shot BRAVO wind data obtained at H-hour and H+6 hours reveal very little change in wind direction and speedin the layer from the surface to 6.1 km,1.-e., easterly trade winds of 10 to 15 knots below 2.1 km and west-northwesterly winds of 10 to 15 knots between 2.1 and 6.1 km (Reference 2). Based on these winds, fallout originating from the BRAVOcloud stem in the upper portion of the latter layer, at about a 5 km height, would have been deposited in a wide area extending tens-of-miles southwest of ground zero. The mid-time of fallout deposition on YAG-40 was H+12.5 hours, implying an average particle fall speed of approximately 400 m/hr. Air samples on YAG-40 measured about 0.5 uCi/m3 ofactivity throughout a 7-hour period of fallout deposition, and imply a buildup rate of approximately 200 wCi/m2/hr. With decay accounted for, some 1.2 Ci/m2 had deposited on the weather decks by the time fallout ceased at H+16 hours. This corresponds to a peak intensity of approximately 6 mR/hrat the conclusion of fallout deposition (Reference 14). Figure 3.9 depicts the estimated topside radiation environment of MOLALAbased on the YAG-40 air sampling data. Radiological decay after 2300 hours, 1 March (H+16), is based on measured decay rates on other ships receiving Shot BRAVOfallout. At 1317 hours, 2 March, MOLALAshortened the tow wire to YAG-40as it prepared to enter Enewetak Lagoon (Reference 3). At 1708 hours, YAG-40 was cast off in berth G-7, approximately 2 nmi west of Parry Island (see figure 1.3); MOLALAanchored approximately 500 yards north in berth F-7. MOLALAremained at anchor in Enewetak Lagoon until 11 March, when, after embarking several Project 6.4 personnel, it got underway for Bikini Atoll in company with YAG-39 and YAG-40. These three ships arrived at Bikini at 0830 hours on 12 March and,at 1630 hours, they got underwayfortheir assigned operating area for Shot ROMEO, scheduled for 13 March. Shot ROMEOwaspostponed andall three ships reentered Bikini Lagoon during the morning of 13 March and anchored in the Nan anchorage area (figure 2.1). On 14 March, MOLALA moored alongside YAG-40to refuel from 1625 to 1747 hours. Topside intensities on YAG-40 had decayed to less than 0.5 mR/hrby this time (Reference 13); hence, exposure to MOLALA's crew while alongside YAG-40is insignificant (see Appendix). Shot ROMEO wasdelayed until 27 March, and during the interim period 15-25 March, except for a brief 4-hour sortie out of the lagoon on 21 March, MOLALAremained in the southern 46