Evaluation of techniques for control of disinfection by-products: a pilot study.

The purpose of this study was to evaluate the effects of various treatment processes as they relate to the development of disinfection by-products (DBPs). At an existing municipal water supply, several tests were performed, including: air-stripping, potassium permanganate (KMnO4) addition, pH adjustment, evaluation of corrosion control inhibitors, final disinfection, and granular activated carbon (CAC) filtration. Several HAAs were shown to increase at higher pH. The use of air stripping greatly reduced the required amount of chlorine disinfectant. Air stripping, permanganate addition, and chloramination reduced DBPs below 20 microg/L. Stiles-Kem 7840 addition effectively controlled lead and copper concentrations in the distribution system. The use of chloramination its a secondary disinfectant is recommended to meet stage 1 of the disinfection by-product rule.