A．solid mining wastesB．the slurry in which the waste is……
Passage One
Questions 57 to 61 are based on the
following passage. The most pressing nuclear energy issue is
the disposal of nuclear waste. Even if all the reactors in existence were
completely safe to operate, there would still be unsolved issue of what to do
with the waste from generating electricity by means of nuclear energy. Those who
claim that they feel comfortable with nuclear energy are, none the less,
concerned about waste disposal methods. Seven states, including California, have
put the building of nuclear plants on hold until legislators are convinced that
there is a safe way to dispose of the radioactive waste from the
plants. In the meantime, pools of liquid waste and piles of
solid waste from private industry and governmental bomb production grow. Since
1962, the volume of radioactive waste produced by the nuclear power industry has
amounted to about 4,300 cubic meters. By the end of the twentieth century, if
production continues at the same rate, there will be 40,000 cubic meters of
nuclear waste. Power plants and bomb-making are not the only
sources of waste. Uranium mining and milling operations have dumped 24 million
metric tons of radioactive tailing wastes at dumping sites around the nation. At
places where uranium is currently milled, there is another 100 million metric
tons of tailings. Uranium tailings are solid materials in the slurry (or watery
mixture) of depleted ore-bearing rock, chemicals, and liquids that result from
milling. Usually, the slurry is piped to holding ponds. When a uranium mill goes
out of business, the ponds are left to evaporate, uncovering piles of dried
tailings. Uncovered piles of tailings give off radioactive radon gas. Once in
the air, the gas finds its way into the water supply and the food chain.
Consequently, many nuclear experts agree that uranium mill tailings may be more
dangerous than high-level radioactive wastes from reactors and
bombs.
It can be inferred from the passage that the most dangerous by-product of uranium mining and milling is ______.
A．solid mining wastes B．the slurry in which the waste is stored C．the radon gas that is emitted by the waste D．the uranium that is recovered in the mining operations
