TABLE I AEC OCEANOGRAPHY PROGRAM 1968 Expenditures Estimate _Research Activities_ Division of Biology and Medicine $4,000,000 Studies of uptake, concentration, distribution and effects of radioisotopes on marine life, of geochemical cycling of elements, and of geophysical diffusion and transport. Division of Research 25,000 Geological dating of corals and other marine and terrestrial materials. Division of Isotopes Development 190,000 Radioisotope applications to devices for marine systems, such as current meters, analysis and recovery of sedimentary minerals, and underwater sound transmission. Division of Reactor Development and Technology 197,000 Studies of factors affecting dissolution and dispersal of accidentally released radionuclides, and site evaluations. Division of Space Nuclear Systems 275,000 Nuclear power sources for aerospace applications. Division of Military Applications 850,000 Ocean environmental observation and prediction. _Total—Research Activities_ 5,537,000 _Engineering Activities_ Division of Reactor Development and Technology 5,900,000 Radioisotope and reactor power development. Division of Naval Reactors 1,320,000 Deep submergence research vehicle. _Total —Engineering Activities_ 7,220,000 _Total—ABC Oceanographic Activities_ 12,757,000 Radionuclides (radioactive atoms) can find their way into the sea from natural radiation sources or from nuclear energy operations undertaken by the United States and other countries since 1945. Specific man-made sources in the past may have included nuclear weapons tested in the atmosphere and under water, the cooling water and wastes of nuclear reactors, laboratories and nuclear-powered ships, containers of radioactive waste disposed of at sea[5], radioisotope energy devices, and intentional injection of radioisotope tracers for scientific research. In the future, they may also include reentry from space of upper-stage nuclear rockets or satellite-borne nuclear energy sources.