Environmental radioactivity levels: Browns Ferry Nuclear Plant annual report, 1980

Increased levels of radioactivity were observed in milk, rainwater, air particulates, heavy particle fallout, vegetation, and in atmospheric radioiodine in October, November, and December following the atmospheric nuclear weapons testing conducted by the Republic of China in mid-October. This increase was seen in control stations as well as indicator stations, and was widely reported in the eastern portion of the United States. Levels of 131I in milk as high as 1.2 pCi/1 were observed. The primary radioisotopes identified in the atmospheric media were 95Zr, 95Nb, 131I, 214Bi, and 103Ru. Dose estimates were made from concentrations of radioactivity found in samples of environmental media. Media sampled include, but are not limited to, air, milk, meat, vegetation, drinking water, and fish. Doses estimated for persons at the indicator locations were essentially identical to those determined for persons at control locations. Greater than 99% of those doses were contributed by the naturally occuring radionuclide potassium-40, and by strontium-90 and cesium-137 which are long-lived radioisotopes found in fallout from nuclear weapon testing. It is concluded that there were no significant increases in environmental radioactivity attributable to the operation of Browns Ferry Nuclear Plant. 5 figures, 26 tables