AWWA WQTC50379

In this study, the formation of HAA9 was examined at granular activated carbon (GAC) run times when HAA5-based treatment objectives were exceeded. The relative control of HAA9 formation based on MCLs set for HAA5 is an important public health issue because although the toxicological properties of these compounds are not fully understood, health effects studies indicate that these compounds are carcinogens. As mandated by the Information Collection Rule (ICR), surface water utilities serving a population over 100,000 (treating a source water with total organic carbon (TOC) concentration greater than 4.0 mg/L) or groundwater utilities serving a population over 50,000 (providing a finished water with TOC concentration greater than 2.0 mg/L) were required to perform a treatment study to evaluate GAC or membranes for the removal of DBP precursors. The rapid small-scale column test was utilized as the bench-scale method to simulate precursor removal by GAC. Both a 10 and 20 minute empty-bed contact time were simulated during each of the four quarterly runs used to evaluate seasonal variability. DBP formation by disinfection with free chlorine was simulated in the GAC effluent samples by utilizing site-specific chlorination conditions designed to match the distribution system conditions of the utility (SDS chlorination). Includes 5 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

01/01/1999

File Size:

1 file , 250 KB