AWWA ACE65338

More and more utilities are using chloramines in place of free chlorine because of their greater stability for better compliance with both the Total Coliform Rule and more stringent requirements of the Disinfectants/Disinfection Byproducts Rule. New information about disinfectant-induced changes in oxidation reduction potential (ORP), lead chemistry, scale formation and interactions with natural organic matter have contributed to greater understanding of the factors influencing increased corrosion and metals release associated with a change in disinfectant. This paper provides a brief overview of Pb(IV) theoretical considerations as applied to metals release in the distribution system. In addition, this paper provides preliminary data and information based on ongoing laboratory and field studies aimed at understanding the impact of a change in disinfectant on lead, brass, and copper components in the distribution system. Results from this study will be of interest to utilities that are considering converting from free chlorine to chloramines, and/or utilities concerned with maintaining simultaneous compliance with the Lead and Copper Rule and the Stage 2 D/DBPR. Includes 29 references, figures.