Section 3 SHIP OPERATIONS This section describes the assignments, activities, and movements of the eight TG 7.3 ships ofinterest at the Pacific Proving Grounds during Operation CASTLE,and correlates these movements with the radiation environment following the six detonations in the test series. Ship movements are reconstructed primarily from data contained in the deck logs (Reference 3). 3.1 PROJECT SUPPORT. As indicated in the following chronologies, task unit assignments do notfully describe the activities of the various ships. In several cases, ships were called upon to provide assistance and services to projects conducted at several of the events. To the extent that these assignments involved radiation exposures, they are documented and included in the dose calculations for the personnel. However, such activities that involved boarding of other vessels by limited parties are not included in the determination of dose to typical crewmembers. A brief discussion of the projects and activities conducted by the various ships supporting the projects follows. 3.1.1 Project 3.4 - Sea Minefield Neutralization by Means of a Surface Detonated Nuclear Explosion (Reference 10). RECLAIMER, SHEA, and LST-1157 participated in this project, conducted by the U.S. Navy Bureau of Ordnance. The project involved emplacementof a field of 121 naval mines in a set of “strings” at various distances from surface zero prior to Shot UNION. NOTE: Dose calculations for USS LST-1157 have been provided previously--Reference 11.) Prior to the actual mine laying operations, RECLAIMER,assisted by LST-1157, laid marker buoys for the minefield in Areas Dog and Fox (figure 2.1). The mines, which wereinert, had been assembled in strings aboard LST-1157 and were then transferred to RECLAIMER. RECLAIMERplanted thefirst set of 96 mines during the period 10-13 April in anticipation of the originally-scheduled date for Shot UNION (16 April). The remaining 25 mines wereoriginally planned for emplacement at Shot YANKEE. Several weather delays reduced the time window available between Shot UNION (ultimately rescheduled for 26 April) and Shot YANKEE(5 May), 19