PITTSBURGH -- A new 40-mgd drinking water treatment system, to go online by the end of the year, will be the largest ultraviolet disinfection system in the US for municipal drinking water, according to Calgon Carbon Corporation.
The contract with West View Water Authority in Pittsburgh, Pa., will provide a Sentinel UV disinfection system to help treat the water for this community of 200,000. In a ten-year service agreement, the company will also service and maintain the system. This will be the first UV disinfection system of its kind in Pennsylvania for surface water treatment.
Construction on the Sentinel unit has begun at Calgon Carbon's facility near Pittsburgh, and delivery is expected in the fourth quarter, according to Bob O'Brien, senior vice president of the company.
Currently, the plant uses chlorine to disinfect the drinking water after it goes through a standard process of coagulation, settling and activated carbon filtration. After chlorine is added, fluoride is added and the pH is stabilized with sodium hydroxide.
"Sentinel will not change anything in the treatment process, but it will provide an additional barrier against giardia, viruses and cryptosporidium," O'Brien said.
Since UV technology does not produce the byproducts that chlorine does, it would be helpful to West View to use the Sentinel instead of chlorine disinfection, but O'Brien explained that the State of Pennsylvania does not currently give CT credits for this type of disinfection.
"If this changes in the future," O'Brien explained, "West View Water may be able to reduce the amount of chlorine it uses for disinfection, which could have a positive effect on disinfection byproduct levels."
West View reported in its 1998 Consumer Confidence Report (available through http://www.waterdata.com) that its TTHMs ranged between 17 and 60 ppb, still well below the Environmental Protection Agency (EPA) maximum of 100 ppb.
For more information, visit Calgon Carbon Corporation's web site (www.calgoncarbon.com).
