Page:Operation Crossroads 1946.pdf/80

 The nine programs managed by the Instrumentation Division are discussed in the following paragraphs. Where appropriate, individual projects within each program are discussed.

Program I -- Bomb Preparation


 * Agency:
 * Los Alamos Laboratory


 * Operations: The bomb for ABLE was prepared at Kwajalein and loaded onto the B-29 drop aircraft on Kwajalein airfield. The bomb for BAKER was prepared on Kwajalein and on medium landing ship LSM-60 in Bikini Lagoon. It was placed in a waterproof caisson and lowered 90 feet (27 meters) under the LSM.


 * Staffing: Seventy Los Alamos Laboratory employees worked on this program. The radioactivity of the nuclear components of the bombs presented a very low risk of exposure. Personnel in this program were not required for reentry operations so they should not have been exposed to significant amounts of radiation. According to exposure records only three individuals were badged (see Table 6).

Program II -- Blast, Pressure, and Shock


 * Agencies: Los Alamos Laboratory
 * Navy Bureau of Ordnance (BuOrd)
 * Navy Bureau of Ships (BuShips)
 * Army Air Force
 * Navy Air Group
 * Air Blast Group (013A)


 * Operations: This program had 28 projects, some with several subprojects (see Appendix C). Except for Project II-12, which measured fireball growth using cameras, all these projects were associated with pressure, blast, and shock measurements. A variety of self-recording airblast gauges were placed on Bikini islands, in the lagoon, on target ships, and on aircraft aloft in the area above the target area. Condenser gauges were dropped from two B-29 aircraft just before each detonation and they transmitted readings to recorders in the B-29 aircraft. Water-shock gauges were also used. All B-29, F-13, and B-17 aircraft participating in either shot carried instrumentation also.


 * Staffing: Personnel from the Air Blast Group, Los Alamos Laboratory Group, Electronics Group, and the BuOrd Instrumentation Group worked on projects in Program II. Although there were probably more, 51 personnel have been identified with this project from existing records, 35 of whom were badged. The highest exposure of these 35 was 0.99 R for an individual working on project II-18 who got all of his exposure the first week in August.


 * Placement of gauges in aircraft, target ships, islands, etc. should have provided little or no exposure to project personnel. Removal of gauges after ABLE should have been relatively easy as radioactivity was limited to a few target ships and decayed rapidly. BAKER, however, contaminated islands due north of the detonation, the lagoon, and most of the target

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