Ra-226 collective dosimetry for surface waters in the uranium mining region of Pocos de Caldas

Graphs of the collective dose equivalent for the whole body, bone, gastro-intestinal tract (lower large intestine), kidneys, and liver, via the pathways of drinking water and ingestion of food grown in irrigated fields are presented as a function of the 226Ra concentrations in the surface waters of the Pocos de Caldas region. The collective dose equivalent calculated from the 226Ra concentrations measured in the baseline studies are compared with those collective dose equivalent estimated from the projected higher 226Ra concentrations in the river waters. The 226Ra concentrations in river waters of the region are expected to be enhanced due to 226Ra releases from uranium mining and milling operations. The dose equivalent commitment for the exposed population for the referred pathways is also estimated for the contribution of the mine during its predicted time of operation. The assumptions for the dose calculations are presented and the results obtained are discussed. (H.K.)