the remainder of the afternoon and early evening and, by 2000 hours, 1 March, when fallout ceased, average topside intensities on COCOPA were 110 mR/hr. Figure 3.4 depicts the topside radiation environment on COCOPAresulting from Shot BRAVOfallout. There is no mention in the ship's log of the washdownsystem being utilized during fallout; however, the rapid decrease in topside intensities between 2000 and 2400 hours, 1 March (H+13.25 to H+17.25), and again from 0400 to 1200 hours, 2 March (H+21.25 to H+29.25), indicates that some shipboard decontamination was likely accomplished prior to COCOPAreturning to the Nan anchorage at approximately 1530 hours, 2 March. Reference 8 states that all major ships exposed to BRAVO fallout at Bikini required decontamination. During the period 3-4 March, COCOPA spent most of the time in the Nan anchorage performing duties to support Project 1.4. These duties included aiding in the decontamination of YC-1081, a Project 1.4 barge that had been left in the lagoon for Shot BRAVO. During the afternoon of 5 March, COCOPAsteamed to Area Charlie (see figure 2.1) to lay the moor for Project 1.4 instrumentcans being set up for Shot ROMEO. The following day, the ship departed Bikini enroute to Enewetak Atoll, returning to Bikini at approximately 0830 hours, 9 March. On 10 and 11 March, COCOPA completed laying Project 1.4 buoys and instrument cans in Area Charlie and, on 12 March, the ship got underway with the two Project 1.4 barges (YCV-9 and YFN-934) in tow for its assigned operating area for Shot ROMEO, scheduled for the following day. Shot ROMEOwas postponed due to unfavorable weather and COCOPAreturned to Bikini and anchored in the Nan anchorage at 1043 hours, 13 March. Continued unfavorable weather delayed Shot ROMEO for two more weeks. During the interim period, COCOPA remained in the lagoon performing various duties as directed, primarily in support of Project 1.4. Because of the long weather delay, batteries and time clocksin the instrument cans had run down and it was necessary to recover the instrument cans for maintenance (Reference 12). At 2012 hours on 26 March, COCOPAproceededto its assigned operating area for Shot ROMEO with only one project barge (YFN-934) in tow (the decision had been made to leave YCV-9 in the Nan anchorage for Shot ROMEO). When Shot ROMEO was detonated at 0630 hours, 27 March, COCOPA was approximately 40 nmi southeast of surface zero. At approximately 1400 hours, the ship returned to Bikini and anchored in the Nan anchorage off Eneu Island. The ship shifted berths to the Tare anchorage just north of EnemanIsland (see figure 2.1) during the morning of 28 March and, during the late afternoon, the ship began receiving secondary fallout from the Shot ROMEOcloud. Topside intensities peaked at midnight on 28 March when radiological survey indicated average 31