AS an integral part of the proving ground, aside from considerations of housing, utihties, etc., facilities for drone plane operations were constructed on Eniwetok island. These facilities involved construction of a radiological-chemistry laboratory for the handIing and dispatching of air radiolo@wl samples, drone Plane arrester gear, drone control insta~ations and a parking area for the contaminated drone planes. Also, on Eniwetok, a reinforced vault for temporary storage of bomb parts was constructed and an air-conditioned film storage space was provided. In general, these were the tasks that developed and confronted Joint Task Force Seven as the planning stage of Operation Sandstone progressed through October and November 1947, passing into the operating stage in the latter part of November. In the beginning, during the period of preparation for construction, the job broke down into four segments of development, the burden of which was upon the Engineer Section and J-4. One group of Engineers worked closely with the AEC Engineers and participating Services in developing test construction designs and accompanying bills of material. A second group concerned itself with construction and materials estimates for housing and utilities and the formation of construction and equipment lists. A third group developed and, through JA, put into operation the Engineer procurement plan. The mapping and survey requirements of the operation were developed and the organization of the field forces which would perform the construction of the proving ground was devised by still another group. Operational planning and the equipping of the field construction force occupied the attention of the Task Force Engineer. By 7 October, 11 days prior to the actual activation of Joint Task Force Seven, decision had been reached by General Hull to contract for the erection of all towers and to perform the balance of the work with soldier labor, pending examination of the test site. The Western Ocean Division of the Corps of Engineers completed an agreement with the contractors, ~orrison Knudsen-Peter Kiewit Sons, Inc., for tower construction on 13 October. By 14 October, the Task Force commander had completed arrangements to use the 18th Engineer Construction Company and the 2nd Engineer SpeciaI Brigade as construction troops. One bit of foresight at this time later paid off in substantial savings in time. The AEC had previously purchased the three 200-foot towers and had them in storage at Sandia, N. M. These towers had been especially designed for the proving ground and had no record of previous erection. Test erection of one of the towers was made at Sandia, resulting in a familiarity with the component parts that greatly helped in the construction at the test site. Based on a reconnaissance of the forward area during the latter part of November it was decided to contract with the Hawaiian Dredging Company, Ltd., for the construction of the connecting causeway between Aomon and Biijiri islands as well as for construction of the foundation for the 75-foot photographic tower to be placed on the coral shoal in the lagoon. In both cases, steel sheet piling was to be used. By this time agreements had been reached between concerned Task Force members, including the staff of the Scientific Director, and members of the participating Services, which laid the basis of co-ordination for all future work and for the control of all subsequent construction operations. From these agreements was evolved the test construction 95