vot a ree ‘eee wet Dee mt oe te ean ant hkl td 1. Fallout Deposition 1.1 Monthly Precipitation 1.11 sSr?° ana sr89 in Monthly Deposition at World Land Sites Precipitation and dry fallout are collected over oF monthly periods at stations in the United States and overseas. The samples are analyzed for Sr-90 and Sr-89 when it is expected to be present. A description of the sampling network and available data for each site are given in the Appendix, sectionA. Other Isctopes at Selected Sites At a number of stations in the United States, monthly deposition ccllections were analyzed for radiostrontium and other nuclides of interest to the Atomic Energy Commission. Multinuclide anal- yses were discontinued as of July 1967 ard the complete data reported in HASL~193, p. Ii-4 through It-25., Plutonium analyses of monthly depositicn are continuing at New York City, Melbourne, Seatrle, Honolulu, Salisbury, Durban, and Rio de Janeiro. Available data are given in the Appendix, Section C. 1.2 Radiostrontium Deposition at Atlantic Ocean Weather Staticns Measurements Of radicstrontium in precipitation and dry fallout collecticns at four U. S. Ccast Guard Stations in the North Atlantic Ocean are carried out for comparison with land stations in the same latitude band. A description of the stations and availiable data are given in the Appendix, Section B. Surface Air Sampling Prodqram The Health and Safety Laboratory has been collecting surface air particulate samples at stations in the Western Hemisphere since January 1963. The filters are analyzed for a number cf fission and activation product radionuclides. available data are given in A description of the program and the Appendix, Section D. Il ~- 2 % yt te ie oy ween coer Re NT, ape ee ea ETREo -7