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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. the nuclear process involving the danger of radioactivity at its every stage
B. fuel for nuclear reactors producing dangerous wastes
C. the weakness scientists have found in every previous methods
D. the nature of nuclear wastes together with their lengthy life span