USING RSSCTS TO PREDICT FIELD-SCALE GAC CONTROL OF DBP FORMATION

The primary objective of this study was to evaluate the use of the rap id small-scale column test (RSSCT) for predicting the control of disin fection by-product (DBP) formation by granular activated carbon (GAC). DBP formation was assessed by using a simulated distribution system ( SDS) test and measuring trihalomethanes and total organic halide in th e influent and effluent of the laboratory- and field-scale columns. It was observed that for the water studied, the RSSCTs effectively predi cted the nonadsorbable fraction, time to 50 percent breakthrough, and the shape of the breakthrough curve for DBP formation. The advantage o f RSSCTs is that conclusions about the amenability of a GAC for DBP co ntrol can be reached in a short time period instead of at the end of a long-term pilot study. The authors recommend that similar studies be conducted with a range of source Waters because the effectiveness of G AC is site-specific.