length of a test operation, which is primarily determined by the delays incident to obtaining weather conditions favorable for "safe" firing situations, could be shortened if the more difficult shots from the standpoint of radiological hazard were fired at Taongi. 11. The laboratories! requirements for testing have increased over the 17 shots of REDWING and the 6 of CASTLE. At the same time there is a greater awareness of the radiological effects of fallout and greater effort and care is being exercised in preventing deposition of fallout on inhabited areas; this has resulted in a more critical appraisal of safe firing situations. Both of these effects tend to increase the duration of a test operation. This tendency has been attacked by the development of a full dual capability concept which would enable firing two high-yield shots within twenty-four hours of each other. However, the necessity for evacuation, re-entry and recovery operations for large shots at Bikini does not permit full advantage to be taken of the flexibility and efficiency inherent in the dual atoll concept. Further reduction in the length of the operation can be obtained only by firing large shots at Taongi. This would allow the operation at Bikini to proceed without the above delays, and would decrease the weather delays for large shots because of a more favorable radiological safety situation at Taongi. le. The firing of very large shots at Bikini can cause considerable damage to the test structures, diagnostic stations, and. temporary camp buildings in the atoll. - 13 - Appendix "a"