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One of the major problems of nuclear energy is the inability of scientists to discover a safe way to dispose of the radioactive wastes which occur throughout the nuclear process. Many of these wastes remain dangerously active for tens of thousands of years, while others have a life span closer to a quarter of a million years. Various methods have been used to date, but all have revealed weaknesses, forcing scientists to continue their search.
The nuclear process involves several stages, with the danger of radioactivity constantly present. Fuel for nuclear reactors comes from uranium ore, which, when mined, spontaneously produces radioactive substances as by-products. This characteristic of uranium, ore went undetected for a long time, resulting in the deaths, due to cancer, of hundreds of uranium miners.
The United States attempted to bury much of its radioactive waste material in containers made of s
A. discover the characteristic of nuclear process
B. discover the nature of uranium ore
C. save the life of uranium miners
D. store nuclear wastes in underwater tanks