Flocculation Treatment BMPs for Construction Water Discharges

This report presents the evaluation of chemical treatment practices known as flocculation for purifying construction site runoff of sediment, suspended solids and colloidal particles. Flocculation is generally used in combination with traditional sedimentation and filtration methods related to stormwater pollution prevention and dewatering fluid treatment. In particular, this report presents the best management practices (BMPs) for evaluation and design of flocculant treatment methods and technologies and the associated sizing for flows representative of field operations. Soil samples from across Minnesota, representing the wide range of geologic and geomorphological conditions, were used to identify differences in flocculant applicability and effectiveness.