Energy Dispersive Analysis of Actinides, Lanthanides, and Other Elements in Soil and Sediment Samples

Abstract

A model is under development at this laboratory to predict the mobilization of Th from an estimated 20,000 metric ton deposit, in place and weathering as long as 80 million years on the Morro do Ferro, a hill on the Pacos de Caldas plateau in Minas Gerais, Brazil. The significance of this deposit lies in the marked similarities, chemically, between Th and Pu with reference to the problem of Pu waste management from the nuclear fuel cycle. One of the objectives of this program is to determine the elemental composition of the Morro do Ferro soil and its relationship to the mobilization of Th from the deposit. X-ray fluorescence is used for the analysis of Th, U, Ba, La, Ce, Pr, Nd, Sm, Dy, Eu, Gd, Yb, Hf , Fe, Zr, N b , Mo and Pb. This paper describes the XRF system and methodology used for the determinations and presents the results of 72 core, soil and sediment sample analyses for the above 18 elements. Analyses of three United States Geological Survey (USGS) rock standards are also presented.

Laboratory-based characterization of plutonium in soil particles using micro-XRF and 3D confocal XRF

“…3 In contrast, use of XRF has been rather limited to detect actinides in bulk soils. 4 For detection of trace amounts of Pu, investigation of individual particles, and in cases where spatial information is desired, micro-XRF based elemental imaging techniques are required. As a result there is more interest in this area of spatially resolved Pu characterization.…”