Recent regulations are now requiring lower chlorinated disinfection by-products (DBPs) and inactivation of chlorine resistant pathogens such as Cryptosporidium parvum. Ultraviolet light is now considered a compliance technology for primary disinfection of surface waters in the Stage 2 Rules.

The objectives to this project were to: 

• evaluate the efficacy of three different UV technologies for treatment of organic contaminants in waters of varying quality; 
• evaluate the UV technologies with additions of hydrogen peroxide (H2O2) to promote advanced oxidation (AOP) for treatment of the contaminants; 
• determine the extent of disinfection by-product (DBP) formation including aldehydes, carboxylic acids, and post-chlorination DBPs, following UV treatment; 
• pilot test two UV technologies alone and under AOP conditions at two utility field sites for contaminant treatment to develop operational experience and preliminary cost and design data.