Pluris Wedgefield, Inc. has been conducting a study with the University of Central Florida Environmental Systems Engineering Institute and Kimley Horn Engineers to address recent detection of elevated levels of total trihalomethanes (“TTHM”). TTHM is a disinfectant by-product of chlorine, which is used to insure bacteria is eliminated in drinking water.
The US Environmental Protection Agency (EPA) in 2006 established the Stage 2 maximum contaminant level (MCL) for TTHM at 80 micrograms per liter (µ/L) and all utilities have been challenged in meeting the Stage 2 MCL. Furthermore all utilities recognize the EPA plans to further reduce TTHM MCLS with additional stages in the future. It is not known for certain when the EPA will implement the next stages, nor what MCLs will be, but utilities and industry experts contemplate the TTHM MCL for Stage 3 to be in the range of 40 µ/L to 60 µ/L. MCLs for Stage 4 is contemplated to be in the range of 20 µ/L to 40 µ/L.
With the challenge of meeting the current Stage 2 and future MCLs, utilities are seeking treatment technologies to insure ongoing compliance.
Findings from the current Pluris study indicate an innovative treatment using chlorine dioxide over traditionally used liquid chlorine as a disinfection is effective in reducing TTHM formation. Although the EPA and the Florida Department of Environmental Protection (FDEP) have approved the use of chlorine dioxide for disinfection; to insure the efficacy, Pluris is conducting a pilot study using chlorine dioxide for disinfection at Wedgefield. The FDEP issued an approval letter to begin the pilot study on November 29, 2016 and upon startup, the pilot study will take 90 days to complete.
Chlorine dioxide has been approved for use in Florida and one utility includes a Volusa County Utility, Magnolia Village. As part of the current Pluris study, Pluris met with Magnolia Village operators, who made the conversion from liquid chlorine to chlorine dioxide when the utility experienced elevated levels of TTHM in excess of 100 µ/L in their drinking water. Regarding the conversion to chlorine dioxide as the disinfectant, the chief water plant operator, Carlos Tola, stated,
“We are extremely pleased with the effectiveness of chlorine dioxide to provide proper disinfection while allowing us to deliver water that is relatively free of TTHMs”.
In the most recent laboratory analytical testing following conversion to chlorine dioxide, documented TTHM levels in Magnolia Village water were between 10 µ/L and 12 µ/L.
To learn more about chlorine dioxide, readers are encouraged to visit the TwinOxide’s website at http://www.twinoxide.us, or contact Joe Kuhns, Regional Manager for Pluris at [email protected].
