Location(s) for Measurement of Filtered Water Turbidity. This policy provides the criteria by which EPA Region 8 determines whether filtered water turbidity is being measured in the appropriate location(s) for determining compliance with the Surface Water Treatment Rules. Turbidity is measured by turbidimeters (which meet the analytical requirements of 40 CFR 141.74(a)).

• Surface Water Treatment Rule Policy #5 (PDF)(6 pp, 241 K, 02/12/2020)