A survey for elevated levels of uranium north of the 300 Area on the Hanford Site

A comprehensive survey of soil uranium (U) concentrations in a study area due north of the 300 Area on the Hanford site has been conducted by Pacific Northwest Laboratory (PNL). The objective of the study was to determine the spatial distribution of uranium in the study area and to ascertain if background levels of uranium have been increased by Hanford operations. Based on the spatial distribution of 238U, the highest concentrations of uranium are located in the southern portion of the study area adjacent to the 300 Area complex and in the most eastern zone of the study site bordering the Columbia River. Uranium-236, an isotopic marker of fuel processing activities in the 300 Area, was detected in all eight samples selected from the study. A significant and positive regression was demonstrated between the ratios of 236U/238U in these eight samples and proximity to the 300 Area. 9 refs., 18 figs., 9 tabs