You are here:
CONTROL OF CRYPTOSPORIDIUM OOCYSTS BY STEADY-STATE CONVENTIONAL TREATMENT
Citation:
Dugan*, N R., K R. Fox*, R J. Miltner*, D A. Lytle*, D J. Williams*, C J. Parrett*, C M. Feld*, AND J H. Owens*. CONTROL OF CRYPTOSPORIDIUM OOCYSTS BY STEADY-STATE CONVENTIONAL TREATMENT. Proceedings paper for 1999 AWWA Annual Conference, Chicago, IL, 6/20-24/99.
Description:
Pilot-scale experiments have been performed to assess the ability of conventional treatment to control Cryptosporidium oocysts under steady-state conditions. The work was performed with a pilot plant that was designed to minimize flow rates and, as a result, the number of oocysts required for continuous spiking. Viable oocysts were fed into the plant influent at a concentration of 106/L for 36 to 60 hours. The removal of oocysts and the surrogate parameters turbidity, total particle counts and aerobic endospores were measured through sedimentation and filtration. There was a positive correlation between the log removals of oocysts and all surrogate parameters through the coagulation and settling process. With proper coagulation control, the conventional treatment process achieved the 2 log total cryptosporidium removal credit granted by the Interim Enhanced Surface Water Treatment Rule (IESWTR). In all cases where 2 log total removal was not achieved, the plant also did not comply with the IESWTR's filter effluent turbidity requirements.