Preliminary study of river water in gold mining areas of Cambodia

In Cambodia, artisanal mining has recently come to a social concern because of the possibility to cause environmental degradation and human health problems. The General Department of Mineral Resources of Cambodia is collecting environmental specimens in mining sites to watch the situation. This time, four water samples from Sampov Loon and one from Memong mining site were sent from the Department to Hiroshima University, Japan, and the samples were analyzed by means of PIXE at the University. A volume of 10 μl from each sample was separated and dropped onto 4 μm polypropylene backing foil. The measurement was carried out by using 2.5 MV single-ended Vande Graaff accelerator. A Si(Li) detector (active area, 80mm2; sensitive depth, 5 mm; Be-window's thickness, 25 μm; resolution, 167 eV fwhm at 5.9 keV) was used for both of in vacuo PIXE and non-vacuum external beam PIXE measurement. A computer code PIXS was used for the quantification. The result indicates that there are at least two kinds of water in Sampov Loon and one of them possibly represents polluted condition. (author)