In this eighth data release report, radium-226 and uranium results are presented that supplement data from previous releases of October 1962, January 1963, July 1963, January 1964, July 1964, January 1965, and July 1965. The data indicate evidence of uranium mining and milling from analysis of composite water samples at stations of the Radium Monitoring Network of the Colorado River Basin Water Quality Control Project. The network is a surveillance system consisting of continuous surface water sampling at 27 locations throughout the basin. It assays the radiological content of river water over the entire basin. Tabular data are given.