Water quality along the Sone River polluted by the Orient Paper Mill

Water quality was sampled at 15 stations along a 216 km stretch of the Sone river and similarity with respect to 7 quality parameters established by hierarchical cluster analysis. The river received effluents from the Orient Paper Mill, one of the largest in Asia, at Amlai, and maximal pollution levels were noted up to 30 km downstream from the mill. Further downstream, quality improved. The most marked quality difference was that between samples taken at the mill's intake point and samples from the effluent mixing point 2 km downstream.