Abstract |
Plant-scale studies at seven water utilities using the Ohio, Allegheny, Beaver, and Monongahela Rivers as their source of supply evaluated various water treatment process modifications for both the control of trihalomethane levels and the modifications' impact on bacteriological quality of the finished water. Process modifications studied, based on comprehensive organic analysis, included relocation of the chlorine application point, chlorination/ammoniation, partial or complete substitution of chlorine dioxide for chlorine, and placement of four different types of virgin granular activated carbons in filter beds. Supplemental studies included organic analysis of monthly raw and finished water samples collected for a one-year period at each of 11 participating water utilities. In addition to providing plant facilities and personnel, the 11 utilities joined USEPA in funding this project, which was conducted by the Ohio River Valley Water Sanitation Commission. |