where available, because experience at IVY indicated that blueboxes were not always reliable. Hcwever, toward the end of this operation bluebox signals were used where feasible, because cf the satisfactory performance of the modified blueboxese At the raft stations, the IFC timing signal came from the Project 25a nondirectional, photoelectric, trigger mechanism. 204 MOUNTINGS At the Bikini land stations, the IFC and its batteries were usually mounted in concrete foundations (Fig. 2.9). At the Bikini lagoon stations, the equipment was mounted on wooden platforms bolted to 60-man Navy life floats (Fig. 2.10). These floats were moored to floats identical to those used by Project 2.5b. The Project 2.5a floats in turn were tied to mooring buoys furnished by Holmes and Narver, Inc, At the Eniwetok land stations, the IFC and the wooden battery boxes were dug into the ground flush with the surface (Fig. Zell 2-5 ® PROJECT PARTICI PATION This project participated in Shots 1, 2, 3, and 4 at Bikini Atoll and in Shot 6 at Eniwetok Atoll. It had been originally intended to participate in Shot 5. However, water wave damage to the stations from Shot 4 made participation in Shot 5 impractical. Generally, IFC's were placed in groups of two at Bikini loca~ tions, and singly at the Bikiri IFC's were on an island or raft hr at 30-min intervals and the min at lemin intervals or for 2 raft and Eniwetok stationse Where two station, one was set to sample for 12 other was set to sample for either 24 hr at 5-min intervals. The l-min samples were collected for Project 2.6b to deterrtine the degree which the base surgs was contributing to the residual contamination pattern. The 5-min interval instruments documented the early fallout and the 30=min interval instruments documented the fallout for the mximum length of time possible with this instrument. Where one IFC was located at a station or raft, it was set to sample at 30—min intervals for 12 hr. The station locations and timing intervals are listed in Tables 2ely 202, and 2.3 and shown in Figse 2.12 and 2.16. 2.6 OPERATIONS Operations were extremely difficult following Shot 1. Immediately following this event, the project's main base of operations at Tare was razed by fire and most spare parts, auxiliary equipment, and operational supplies were lost. Th? long delay before Shots 2, 4, and 6 imposed additional difficulties because the batteries readily dis- charged in the hot waather,requiring frequent trips to the stations with battery replacements. Heavy seas in the Bikini Lagoon caused the cancellation of the Bikini raft station program. The rafts broke away from their moor~ ings with distressing frequency. Locating and mooring the rafts in 19