a. The tests would provide the Armed Forces with an invaluable opportunity to participate in atomic weapon development; would therefore prove an excellent training vehicle; and would, from the overall viewpoint, be of inestimable value in the gain - to national preparedness and security. b. Although the Commander, Joint Task Force Seven, was charged with responsibility for the conduct of the entire operation, Sandstone was primarily a scientific test with the Armed Forces in a supporting role. c. The security requirements imposed by the Atomic Energy Act of 1946 would be a controlling factor in the conduct of the operation. d. The major expenditure of effort by the Armed Forces in support of this operation would be logistical in nature. e. The international political situation would be an influencing consideration in conducting the operation. The fact that Operation Sandstone was conducted for the fundamental purpose of scientific proof-testing an improved design of atomic weapons by the Atomic Energy Commission, but was under the command of a military officer, posed a special problem of organization within the Task Force. This problem was solved by the organization of Task Group 7.1, to which all AEC members of the Task Force, both civilian and military, were assigned. The Test Director and Commander of Task Group 7.1, Captain Russell, and the Scientific Director, Doctor Darol K. Froman, who also headed Task Unit 7.1.1 within Task Group 7.1, were not subject to staff direction of the Joint Task Force Staff. By mutuai agreement the channel between this Task Group and the Task Force Commander was direct. This solution did not impair the command function of the Commander, Joint Task Force Seven, while at the same time it provided the freedom of action necessary to the scientific elements of the Task Force. Viewed in perspective, it might be said that the Task Force existed and operated to support one of its own subordinate elements. The security provisions of the Atomic Energy Act of 1946 served to make the personnel of Joint Task Force Seven security conscious to a high degree. Throughout the op eration, extreme care was exercised to prevent unauthorized access to any data or material of a nature classified as “Restricted Data.” The provisions of the Atomic Energy Act were an important consideration in arriving at the establishment of post-test safeguards at the proving ground. All individuals assigned tr -m associated with the Task Force during this operation were appropriately screened b} me FBI of the Department of Justice. The results of these screenings are noteworthy. A total of over 13,000 persons, including 1,873 who were given the full AEC “Q” clearance, were investigated. Of this number, 11 were rejected because of Communistic tendencies and 20 were rejected for character reasons. Efficiency and economy in the solution of administrative and logistic problems dictated the decision to rely on the existing command channels of the respective Armed Services for this operation. This solution proved to be eminently satisfactory. Normal Zone of the Interior supply installations and ports for all three Services, and the existing Pacific Command channels, namely CincPacFlt, Pacific Air Command and ATC, and US Army Pacific, were utilized for this purpose. Support provided by the Services was unfailingly of the highest order at all times. Designation of an Executive Agent for the Joint Chiefs of iv