STUDIES ON ARSENIC RICH MINE DUMPS .3. EFFECT ON THE RIVER WATER

The effect of arsenic rich abandoned mine dumps on the adjacent river was studied. Soil at the mine dumps contained (mean levels in mg/g) As 9.53, Cu 0.54, Ni 0.97, Co 0.08, Mn 0.84, Pb 0.34 and Zn 0.33. The to tal dissolved elemental concentration in the river was high near the m ine dump compared with upstream and levels gradually decreased along t he downstream. The river water sampled next to the mine dumps during t he rainy season had pH 5.67. The sample contained SO42- 1.59, As 0.025 , Cu 0.072, Ni 0.042, Mn 0.057 and Pb 0.010 (ppm).