Project 2.7 - SURVEYOF~RADIOCLOGICAL FALL-~OUT BY OCEANOGRAPHIC METHODS (T.R. Folsom; F.D. Jennings, J.D. Isaacs, R. Revelle) (Scripps Institution of Oceanography) Objectives To determine the distribution of the major fall-out downwind by oceanographic msthods. To measure depth and rate of diffusion of fall~out required for an estimate of the integral activity over the area, To collect otherwise wmattainable specimens, technical data, and field experience essential for the success of future operational planning and instrumentation. . General Character of the Survey The ATF-75 (Sioux) was hurriedly fitted with hydrographic gear and with improvised radiation detectors capable of being towed and lowered vertically into the sea. Between Y+6 hours and Y+l days an 800 mile long traverse of the suspected downwind area was made, sections being made near radii 30, 50, 100, 150, and 200 miles. Hydrographic casts were made at stations evidencing distinctly active watery water samoles were taken to depths as great as 2,00 feet. Surface water was collected frequently along the traverse while the Ship was in motion. - Between stations, radiation indicators were towed astern so that the Surface water activity could be continuously monitored, At three stations a special geiger counter device was lowred to the &nd of a 300 ft cable and its reading was recorded as a fimction of depth. In two instances, it passed through the contamination and into the clear water Selow giving the extent of diffusion directly, Provide further information of this type. POPIED/DOE LANL RG.” ® : __* Water samples, of course, will