Three aerial radiological surveys were conducted during the period 16 June through 15 July 1986 over the towns of Pocatello, Soda Springs, and Fort Hall, Idaho and the surrounding areas. The surveys were performed for the United States Environmental Protection Agency (EPA) by the United States Department of Energy's (DOE) Remote Sensing Laboratory (RSL), utilizing the Aerial Measuring System (AMS). This work was completed in cooperation with a study by the EPA to conduct a dose assessment of human radiation exposure for industrial sources in Pocatello and Soda Springs, Idaho. The aerial surveys were performed to document the natural terrestrial radiological environment of the three localities and to map the spatial extent and degree of contamination due to phosphate milling operations. The results of these surveys will be used for planning ground-based measurements in addition to being incorporated into the dose assessment document. 4 refs., 14 figs., 6 tabs.