[American Society of Agricultural and Biological Engineers 21st Century Watershed Technology: Improving Water Quality and Environment Conference Proceedings, 29 March - 3 April 2008, Concepcion, Chile - ()] 21st Century Watershed Technology: Improving Water Quality and Environment Conference Proceedings, 29 March - 3 April 2008, Concepcion, Chile - Quantitative Performance Screening Method for Flocculants Based on Particle Size Distribution Data