Along with this On the 9th of April, the original test area was -1- Survey trip, preparation of manuals covering radiation measurement and regulations pertaining to public dissemination of the survey results. These recommendations were tinalized by the Radioactivity Countermeasure Headquar ers. The operation unit of this group, gradually formulated recommendations in regards to the operational aspects of the In order to complete executive planning and to promote the survey trip, the Survey Vessel Dispatch Group was organized on the 15th of May by the Ministries and Agencies concerned, aided by individuals possessing knowledge and experience within this field. During this period the Radioactivity Countermeasure Headauarters, in conjunction with the Fisheries Agency, decided to send one of the Agency's survey vessels, the Shoyo-Maru, to the test area to perform the surveys and tests necessary to fulfill the second requirement. sequent to 25 April, at the Tsukiji Fish Market. survey vessel to the test area in order to determine the exact amount and extent of radioactive fallout and contamination within the mid Pacific area. To fulfill the first requirement, tne Tokyo Metropolitan Government, started a sample survey of fish acquired from the test area sub- Fisheries Agency, concerning plans to send a radiological program during the resumption of nuclear tests, to conduct a survey of fish, available in Japan, that were acquired near the test area. Also, discussions were held with the a meeting and decided, as a part of the radiological safety During the test period, a total of 36 nuclear devices were detonated. In view of the JERRIN PEP3c tonations, the Radioactivity Countermeasure Headquarters of Japan held Island, established. partially enlarged and another test area, near Johnston outlined. announcement, the testing area, near Christmas Island, was on the Sth of April in the Pacific area. Statement that testing of nuclear devices would take place On the 4th of April 1962, the United States issued a HISTORICAL The S.V. Shoyo-Maru was renovated and equipped with the ® Name and health physicist Ship doctor and radiation oth r marjne biologica Specimens plankton and ampling and radfoaot iW iey" measuremen in air and rainwate Radioactivity measurements of oO servaty ong measurements of sea water and Sampling radioactivity environmental radioactivity Measurements_of Duties Director of operation PRIVACYACT MATERIAL REMOVED —-2— and members of the crow issist— Captain 63 well ed the survey team members in oceanographic observe*iois as biological sampling. National Institute of Radiological Sciences Fisheries Agency Seikai Regional Fisheries Research Laboratory, National Institute of Radiological Sciences Japan Hydrographic Office Institute of Physical and Chemical Research Naikai Regional Fisheries Research Laboratory, Fisheries Agency Parent Organization Scientific Personnel Assigned to the Ship cal and meteorological samples for radiochemical analysis. ““diation contamination and to collect biological, oceanographi- OPERATIONAL The operational cruise, conducted in the waters adjacent _to Johnston and Christmas Islands, was designed to survey ra- trip. ni departed from Takeshiba Pier, Tokyo, for the scheduled 55 day necessary instruments and equipment. On the 27th of July 1962, . -the S.V. Shoyo-Maru with a specially assigned Survey team, -f PRIVACY ACT MATERIAL REMOVED PRIVACYACT MATERIAL REMOVED