AWWA ACE93106

Starting in 1990, pilot-plant and full-scale studies of ozone treatment at North American utilities were conducted by the University of North Carolina (UNC). This AWWARF study was performed in association with the Metropolitan Water District of Southern California and other utilities. The project had two objectives: 1) to survey ozonation facilities to determine the occurrence and control of DBPs, including aldehydes, bromate, and chlorination DBPS, and 2) to conduct broad-screen testing and unknown ozone DBPs, first in the laboratory and then in the field. Additionally, the University of Colorado at Boulder has been conducting a nationwide bromide survey to evaluate bromide occurrence and its impact of THM and bromate formation. In particular, both studies have focuses on special investigations into the occurrence and control of bromate. This paper reports principally on the findings of the UNC/AWWARF pilot- and full-scale studies and discusses possible options for controlling/minimizing the formation of bromate in ozonated drinking water. Furthermore, these data and the UCB/AWWARF findings were used as part of a regulatory impact analysis (RIA) for bromate during the D/DBP reg neg. The RIA and implications of the proposed bromate regulation is also discussed.