DELETED VERSION ONLY HISTORY of TASK GROUP 7.4 participation in OPERATION CASTLE 1 January 1953 - 26 June 1954 Prepared by the Historical Division Office of Information Services Air Force Special Weapons Center (Air Research and Development Command) Prepared under provisions of AF Regulation 210-3, 210-3A, and ARDC Regulation 210-1 as a part of the USAF Historical Program. "This Document contains information affecting the National Defense of the United States within the meaning of the Espionage Laws, Title 18, U. S. C., Sections 793 and 794. Its transmission or the revelation of its contents in any manner to an unauthorized person is prohibited by law." Classified material in this report is classified under the provisions of paragraph 23, AFR 205-1, dated 15 December 1953, and in ac-— cordance with Classification Guide for Atomic Energy, dated 6 November 1953. Classified material in this document cannot be reproduced in whole or in part without permission of the office of origin, except under pro-~ visions of paragraph 12, ARDC Regulation 205-4, dated 31 August 1953. Kirtland Air Force Base, New Mexico 8 November 1954 AEWLIHC ad