In addition to receiving fallout while at Bikini and Enewetak, the SIOUX was utilized to "map out" the over-water extent of the fallout following Shots YANKEE and NECTAR. While aiding in this experiment (Project 2.7), the SIOUX was required to steam through water contaminated by fallout and take periodic water samples and sea surface intensity readings. The ship's path through contaminated water and water intensity readings are well documented for a five day period following Shot YANKEE (Reference 13) and it is possible to reconstuct the radiation environment to which the crew was exposed while participating in this experiment. Similar documentation is not as complete following Shot NECTAR since the USS MOLALA (ATF-106) served as the primary water sampling platform during this experiment. The few intensity readings obtained from the SIOUX indicate the ship was in water much less contaminated than it was after Shot YANKEE (Reference 13). The resultant crew exposure would thus be much less. Figure 2-32 depicts the reconstructed radiation intensity of the water through which the SIOUX steamed following Shot YANKEE. Several simultaneous measure- ments made on the deck of the ship indicated deck level (topside) intensities due to "shine" from the contaminated water were approximately 40 percent of the measured water intensities. Prior to its Project 2.7 activities during May, the SIOUX was in and out of Bikini Lagoon on nine occasions between 6 March and 17 April. Integrated intensities due to hull contamination while contamination model. in the lagoon have been determined from the These are detailed below for each period in and out of the lagoon, : Month March ship Time at Bikini Lagoon In 06/1726-09/1316 11/2102-12/0456 13/0810-19/0910 21/1926-22/1908 Integrated Intensity (mR) Out In 110.6 09/1316-11/2102 12/0456-13/0810 19/0910-21/1926 22/1908-26/0141 113 , 5.1 102.4 8.5 Out 38.7 9.5 15.8 16.7