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EPA orders City of Nogales, Ariz. to correct drinking water violations

Release Date: 05/19/2008
Contact Information: Margot Perez-Sullivan, 415.947.4149

SAN FRANCISCO –The U.S. Environmental Protection Agency recently ordered the City of Nogales to correct violations of the nation’s Safe Drinking Water Act, specifically, monitoring for disinfection byproducts.

According to the EPA, the City of Nogales failed to submit a plan detailing how it will monitor and sample for disinfection byproducts that could be produced when chlorine, ozone, or chlorine dioxide are used to disinfect the water. If the city fails to comply with the order, it could face fines of up to $32,500 per day.

“Public water systems must comply with the disinfection byproducts rule to ensure the public is provided safe, clean drinking water,” said Alexis Strauss, Water Division director for the EPA’s Pacific Southwest region. “Providing people with safe drinking water is essential and the City of Nogales must take steps to comply with all federal regulations.”

The City of Nogales provides drinking water for approximately 20,000 customers. Under the terms of the order, the city is required to submit its monitoring plans within thirty days.

Disinfection is a chemical process in which chlorine, ozone or chlorine dioxide is added to drinking water to kill disease causing pathogens. The EPA regulates the concentrations of disinfection byproducts such as trihalomethanes, haloacetic acids, bromate and chlorite, which can be produced when disinfectants are used in water treatment and react with natural organic matter.

After many years of consumption, these chemicals may cause liver, kidney or central nervous system problems and may increase the risk of cancer.

The EPA established new disinfection byproduct regulations in January 2006 to protect public health from potentially harmful byproduct chemicals that form when chlorine reacts with natural organic compounds during the treatment process. The Disinfectants and Disinfection Byproducts rule began regulating public water systems serving 10,000 to 49,999 customers in October 2007.

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