Environmental impact of the coal industry
http://en.wikipedia.org/wiki/Environmental_impact_of_the_coal_industry#Radiation_exposureRadiation exposure[edit]
Coal also contains low levels of uranium, thorium, and other naturally occurring radioactive isotopes whose release into the environment may lead to radioactive contamination.[20][47] Coal plants emit radiation in the form of radioactive fly ash which is inhaled and ingested by neighbours, and incorporated into crops. A 1978 paper from Oak Ridge National Laboratory estimated that coal-fired power plants of that time may contribute a whole-body committed dose of 19 µSv/yr to their immediate neighbours in a 500 m radius.[48] The United Nations Scientific Committee on the Effects of Atomic Radiation's 1988 report estimated the committed dose 1 km away to be 20 µSv/yr for older plants or 1µSv/yr for newer plants with improved fly ash capture, but was unable to confirm these numbers by test.[49] A single PWR spent fuel bundle, after 10 years cooldown, with no shielding, emits 2.3 MSv/yr, a trillion times more than coal.[50] However, if we exclude contained waste and ignore unintentional releases from nuclear plants, coal-plants carry more radioactive wastes into the environment than nuclear plants producing the same amount of energy. Plant-emitted radiation carried by coal-derived fly ash delivers 100 times more radiation to the surrounding environment than does the normal operation of a similarly productive nuclear plant.[51] This comparison does not consider the rest of the fuel cycle, i.e., coal and uranium mining and refining and waste disposal.
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