Occurrence of uranium in drinking water in the U.S.

Uranium is found in ground and surface waters due to its natural occurrence. In some cases, its presence is due to human activities such as mining and milling uranium. Thus, it is also found in drinking water. The range of concentrations existing in drinking water supplies in the U.S. is tabulated and examined. The range of isotopic abundances are also listed. Projections from the available data lead to estimates that of the 59,812 community drinking water supplies in the U.S., 25-650 would exceed a uranium concentration of 20 pCi/l., 100-2000 would exceed 10 pCi/l. and 2500-5000 would exceed 5 pCi/l.