Environmental Effects on sup 222 Rn Fluence Rate from Reclaimed Uranium Mill Tailings

摘要

The author measured (222) Rn fluence rate from 2 plots with uranium mill tailings buried beneath 30 cm of overburden and 30 cm of topsoil. An additional 30 cm of clay covered the tailings on 1 of the plots and each plot was subdivided into bare soil and vegetated subplots. The author also measured a control plot, identical to the plot without a clay cap but having no tailings. In addition to fluence rate, The author measured moisture in each of the plot layers, atmospheric pressure, air temperature and relative humidity during each sampling period. The author used linear correlation, two-way ANOVA and stepwise multiple regression to analyze the effects of the plot characteristics and the environmental variables on (222) Rn fluence rate. The mean fluence rate from the plot having both a clay cap and a vegetated surface was over 3 times that of the vegetated plot without a clay cap and 14 times that of the bare plot with a clay cap. The interaction effect may be due to the proliferation of roots in the moist clay and active transport of dissolved (222) Rn to the surface in water. (ERA citation 12:035695)