AWWA Questions USEPA's Atrazine Method
In the midst of conducting an extensive triazine monitoring project this year, AWWA has learned that USEPA's approved method for compliance monitoring for atrazine has some problems that need to be resolved before they result in utilities potentially being out of compliance from using this method.
J. Alan Roberson, AWWA's director of Regulatory Affairs, has written to Cynthia Dougherty, director of USEPA's Office of Ground Water and Drinking Water, to recommend that revisions be made to the agency's recently approved atrazine immunoassay analytical method, referred to as the Method Syngenta AG-625.
"The problems need to be resolved as soon as possible, as this method is now approved for compliance monitoring," Roberson wrote. "We recommend that revisions should be made to the ... process to ensure that this problem is not repeated as more innovative methods are developed and considered for approval."
Roberson said AWWA's three major concerns are:
Directions for this method do not include requirements for dechlorination of samples prior to analysis, a step researchers have found is necessary to obtain accurate results.
When a water sample has been exposed to chlorine dioxide prior to analysis, an additional interference could occur, but more research is needed with the addition of a reducing agent for the elimination of chlorine products when chlorine dioxide has been added at the plant.
Other water quality constituents could introduce interferences with this method, but more research is needed.
AWWA has suggested that USEPA convene a technical panel to review the current procedures and to develop appropriate guidelines for the approval of the analytical methods for drinking water compliance.
In related action, Roberson recently met with USEPA's Science Advisory Panel to discuss AWWA's current review of atrazine. Among other things, he expressed concerns that many Midwestern utilities are unfairly facing an ongoing financial burden for atrazine removal. "We believe it is fair and equitable for this financial burden to be borne by manufacturers and growers who are responsible for it, not by the drinking water suppliers," Roberson said.
He also said AWWA recommends that the mitigation trigger for atrazine be set at 12 micrograms/L, rather than the 37.5 micrograms/L trigger established by USEPA in its Interim Registration Eligibility Decision in January 2003.
AWWA's ongoing atrazine project includes the weekly monitoring of 40 surface water sources, using both raw and finished water samples. Ten percent of the samples are further being analyzed for triazines and some of their metabolites.