Natural Radium 226 Content of Illinois Water Supplies

Abstract

The concentration of Ra/sup 228/ has been measured in 200 water samples from 159 municipal water sources. Uni-form low concentrations of radium were found in the treated water from all surface sources, whereas both high and low values were found in well water sources. High concentrations of Ra/sup 226/ in nonsandstone wells have been correlated with infiltration of deep sandstone water. Concentrations of Ra/sup 226/ from 1 to 25 mu mu g/l were found in wells obtaining water from the three deep sandstone formations. The highest concentrations of radium are associated with water from the St. Peter formation. Although only a few samples have been analyzed, it appears that the concentration of Ra/sup 226/ in shallow sandstone well water is low in northern and central Illinois and high in southern Illinois. Average concentrations of Ra/ sup 226/ in water from the various source types are tabulated. The averages in this table do not include treated-water samples, raw-water samples, or samples known to contain water from a different source type. It is seen that concentrations of Ra/sup 22/ in excess of 2 mu mu g/l are only found in water from sandstone sources. The effects of various types of treatment ofmore » the water, such as filtration, iron removal, and softening, have not been determined because both raw and treated samples were obtained from a single water source at only twelve sites. All types of treatment appear to reduce the concentration, however. (auth)« less