Skinner, Dawn J., authorWhicker, F. Ward, advisorOlson, H. G., committee memberIbrahim, Shawki A., committee member2022-07-052022-07-051982https://hdl.handle.net/10217/235419This study concerned 226Ra contamination of soils and foliage as a function of distance downwind from a uranium mill tailings pile. In soils the radium contamination was primarily associated with particle sizes < 0.045 mm and mainly found within the 0-0.6 cm soil horizon. The 0-0.6 cm soil horizon showed a decrease in activity concentration with distance. The 0-15 cm and 0-30 cm soil depth samples also showed a significant decrease with distance. An attempt was made using ultrasonic washing to separate internal from external 226Ra contamination in Artemisia tridentata. Internal contamination appeared to be a larger contributor to total contamination at distances ? 0.16 km downwind from the tailings pile. At distances > 0.16 km, external contamination became a larger contributor to the total 226Ra contamination. Concentration ratios (based on total contamination and internal contamination) were determined as a function of distance downwind from the tailings pile. Concentration ratios appeared to be highly site specific, however higher values (0.8-2.8) were generally associated with distances ? 0.16 km from the mill. At distances > 0.16 km. In most soil samples 226Ra concentrations approached background levels at a distance of 1.1 km from the tailings pile. Total vegetation contamination approached background at 6.6 km. A trend of decreasing internal and external 226Ra contamination with distance downwind was found to be significant (p < 5%). This study suggested that a combination of root uptake and foliar absorption were responsible for internal contamination and further studies were suggested.masters thesesengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.Uranium mill tailings -- Environmental aspectsRadioactive pollution of soilsPlants -- Effect of radioactive pollution onText