(Lawrenceville, Ga., May 8, 2009) - Gwinnett County's Water Resources Department is taking proactive steps that will assist the advancement of the science tdetermine the presence of human and veterinary pharmaceuticals and traces of products like cleaners, lotions, and sunscreens in the water supply.

In March 2007, the County contracted with a research group at the University of North Carolina ttest Gwinnett's water for 19 compounds* at four points: the raw water intake for the Shoal Creek Filter Plant at Lake Lanier, processed drinking water after filtration and treatment, wastewater entering the Hill Water Resources Center and treated effluent being returned tthe Chattahoochee River. Part of the purpose was tdetermine whether the best practicable treatment techniques used by Gwinnett facilities was effective at removing these compounds.

The U.S. Environmental Protection Agency sets national standards for water quality under the Safe Drinking Water Act but has not issued regulations for these particular compounds, collectively known as PPCPs. "We believe this study will help develop the science for determining future EPA regulations," said Lynn Smarr, Gwinnett's acting director of Water Resources. "We try tbe on the cutting edge tprotect our residents and keep our environment healthy and safe."

The study by the University of North Carolina used an unusually low reporting limit (MRL) of 10 ng/L (nanograms per liter or parts per trillion), which requires specialty lab equipment tanalyze such low concentrations. Tprovide perspective, one part per million would be $1 out of $1 million, while one part per billion would be $1 out of $1 billion and one part per trillion would be $1 out of $1 trillion. Taken from another angle, Lake Lanier holds over twtrillion liters of water, and it would take 34 years for Gwinnett's drinking water plants tproduce a trillion gallons of water.

Results of the study show:

For wastewater treatment

Most of the 19 targeted compounds were removed tbelow detection limits by the Hill plant:

• Only four (sulfamethoxazole, primidone, caffeine, DEET) were detected at concentrations above 10 ng/L, and those ranged from 10 t140 ng/L;
• Intermediary treatment steps of biological treatment and membrane filtration reduced by more than 80% the concentrations of six compounds (caffeine, acetaminophen, ibuprofen, DEET, tetracycline, 17a-ethynylestradiol);
• The intermediary treatment step of granular activated carbon effectively removed most of the targeted compounds except for DEET, primidone and caffeine; and
• Ozonation oxidized most of the remaining compounds by more than 50%, except for DEET, primidone and caffeine.

For water supply and treatment

• Only caffeine, DEET and carbamazepine were detected in the lake water entering the Shoal Creek Filter Plant for treatment.
• This is consistent with previous studies by the U.S. Geological Survey which, for example, found traces of caffeine and acetaminophen in the Chattahoochee River.
• None of these compounds were found at concentrations above the MRL of 10 ng/L in the finished drinking water
• DEET was occasionally detected, with estimated concentrations ranging from 3 t7 ng/L, which is below the minimum reporting limit.

PPCPs can enter the environment when people flush medications or rinse other products down the drain, through excretion by humans or animals, or by improper disposal methods. They alsenter the environment through normal and proper use, as when we spray ourselves from head ttoe with mosquitrepellant. The reason DEET is spopular in bug spray may be its persistence.

"Although it's not been required, we believe it's important tknow what's in our water and how effective our treatment processes are at removing these compounds," Smarr said. "We are pleased with the results of the study, which shows that if and when the EPA develops regulations that we have the best and most appropriate technology."

Last February, the EPA published on its website a strategy for addressing the issue of PPCPs that includes expanding the science as well as providing education, partnerships and regulations as necessary.

The Hill Water Resources Center has been widely praised for its state-of-the-art process that uses ozone disinfection in addition tfiltration and membranes. Ozone is one of the strongest and most effective oxidizing agents known for the elimination and removal of PPCPs. Gwinnett currently discharges treated wastewater intthe Chattahoochee River and is scheduled tbegin returning it tLake Lanier later this year. The lake is alsthe source of raw water for both of Gwinnett's filter plants that produce finished drinking water for more than 800,000 residents. The filter plants alsuse ozone disinfection in addition tfiltration and chlorination tprovide safe drinking water.

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*Testing was conducted for the presence for the following PPCPs: