Preliminary to the shot phase of IVY, installation of special equipment in various ships and planes of the Task Group to support the scientific projects had been no small part of the planning and preparation, The final planing phase included the stationing of scientific personnel on the ships ‘to carry out their missions, 1. . Project 5.4a, including the Dan Buoy Project (Fallout Distribution and Particle Size), involved 4 ships and thePatrol Plane Unit on a primary mission basis and 10 ships on a supporting basis. the project was sponsored by the Department of Defense, conducted by the Naval Radiological Defense Laboratory, UavshipYd, San Francisco, and the project officer was LCDR HEIDT of the Buroau of Ships. | The project involved some hazard to security due to radar contacts on Dan Buoys hindering A3v! patrols but was considered important enourh to accept & calculated rink. The original concept was to lay 3 lincs of 10 Dan Buoys each at 30, 100 and 150 :.iles from Ground Zero, A letter was addressed to Cammandor in Chief, U.S. Pacific Fleet, via QJTF 132, recommending accoptance. of the reduced security, CJIF 132 returned the letter by endorsenent indicating approval, However, by later despatch action, Commander in Chicf, U.3. Pacific. Fleet, considered the innor line of buoys as an unacceptable security risk. Thus, only two lines of van Buoys were laid, cancelling all buoys inside 75 miles of Ground Zero. _ The UiS YUMA participated on a primary mission basis frow 0630, }. minus 3 to 0910 to :. minus 2 Day to lounch Dan Buoys and was scheduled froz 0700 . “Dy - BEST AVAILARLE Copy