Biogeochemistry of 226Ra in contaminated bottom sediments and oilfield waste pits
Document Type
Article
Publication Date
6-1-1998
Abstract
Solubility of 226Ra in sediments contaminated by produced water discharges was investigated using integrated microcosm, geochemical modelling and field sampling techniques. These studies strongly indicate that the biogeochemical control on 226Ra solubility in these sediments is coprecipitation with barite (BaSO4). The role of barite was confirmed by selective extractions of contaminated sediments, geochemical measurements of solution saturation, theoretical coprecipitation calculations, and direct measurement of barite using X-ray diffraction. Despite elevated activities that are three orders of magnitude higher than background, fluxes of 226Ra from these contaminated sediments are of the same order of magnitude as those measured in natural systems. Remobilization of 226Ra was observed in the Humble Bayou sediment under anaerobic, sulfate-reducing conditions. Management of these contaminated sites will involve understanding the role of barite solid-solution chemistry on the fate and mobility of 226Ra.
Publication Source (Journal or Book title)
Journal of Environmental Radioactivity
First Page
239
Last Page
253
Recommended Citation
Pardue, J., & Guo, T. (1998). Biogeochemistry of 226Ra in contaminated bottom sediments and oilfield waste pits. Journal of Environmental Radioactivity, 39 (3), 239-253. https://doi.org/10.1016/S0265-931X(97)00047-7