October 22, 2009 

U.S. Environmental Protection Agency 

Office of Pesticide Programs (OPP) 

Regulatory Public Docket (7502P) 

1200 Pennsylvania Ave NW 

Washington, DC 20460-0001 

RE: Atrazine Evaluation 

 Docket EPA-HQ-OPP-2009-0759 

Dear Docket: 

The American Water Works Association (AWWA) is an international, nonprofit, 

scientific and educational society dedicated to the improvement of drinking water quality 

and supply. Founded in 1881, the Association is the largest organization of water supply 

professionals in the world. Our 57,000-plus members represent the full spectrum of the 

drinking water community: treatment plant operators and managers, environmental 

advocates, engineers, scientists, academicians, and others who hold a genuine interest in 

water supply and public health. Our membership includes more than 4,200 utilities that 

supply roughly 80 percent of the nation's drinking water. 

AWWA appreciates the opportunity to comment on the new comprehensive evaluation of 

atrazine. AWWA has been closely following the re-registrations for atrazine and the 

other triazines since Maximum Contaminant Levels (MCLs) for these herbicides were 

promulgated in the early ‘90s. Atrazine and other triazine herbicides have been a 

significant issue for AWWA and its member utilities for many years, due to the potential 

for groundwater and surface water contamination from these herbicides. Protection of 

drinking water sources and prevention of contamination should be the ultimate objective 

for EPA’s regulatory programs. 

Many surface water utilities in the Midwest had to install carbon treatment (and pass on 

those costs to their customers) to comply with these MCLs in the ‘90s. Typical carbon 

treatments used in water treatment plants to remove these herbicides have significant 

operation and maintenance costs (beyond the initial capital construction costs) that will 

be borne by their customers in perpetuity. EPA’s regulatory programs should address 

this cost shifting issue within its regulatory programs so that the registrants are ultimately 

responsible for these life-cycle costs. 

Government Affairs Office 

1401 New York Avenue 

Suite 640 

Washington, DC 20005 

T 202.628.8303 

F 202.628.2846 

www.awwa.org

Headquarters Office 

6666 W. Quincy Avenue 

Denver CO 80235 

T 303.794.7711 

F 303.347.0804 

The Authoritative Resource on Safe Water SM
Docket EPA-HQ-OPP-2009-0759 

October 22, 2009 

Page 2 

For more than 20 years, AWWA has written multiple letters to EPA and Congress 

expressing our concern with the impacts of agricultural chemicals, including the triazines, 

on drinking water supplies. AWWA has written extensive comments on EPA’s proposals 

as part of the atrazine reregistration process. Additionally, AWWA and the Water 

Research Foundation have conducted substantial research on the impacts of these 

herbicides to utilities, and a list of some of the published papers resulting from that 

research is included at the end this letter. 

AWWA would like to emphasize three issues to EPA and the Scientific Advisory Panel 

(SAP) as part of the comprehensive evaluation of atrazine: 

1. AWWA strongly supports the use of “...the best available, peer-reviewed 

science...” in the regulatory development process, as this specific language is one 

of the cornerstones of the Safe Drinking Water Act (SDWA). AWWA supports 

EPA and the SAP in its efforts to evaluate the new scientific evidence and 

determine how this new evidence might (or might not) impact the agency’s 

human health risk assessment of atrazine. 

2. AWWA believes that the policies and regulations from both the Office of 

Pesticide Programs (OPP) and the Office of Groundwater and Drinking Water 

(OGWDW) must protect drinking water sources. Atrazine MCL violations have 

been reduced from 81 in 1995 to three in 2007, but what is not known is how 

much of the reduction is due to improved stewardship at the farm level or whether 

the reduction is due to many surface water utilities in the Midwest installing 

carbon treatment, as previously discussed. 

3. AWWA supports registrant monitoring requirements being a typical component 

of the re-registration process for pesticides with moderate to significant drinking 

water exposure. The monitoring data developed by Syngenta has been useful in 

developing a better understanding of atrazine drinking water exposure. This type 

of monitoring program should be a typical component of the re-registration 

requirements in OPP. 

The regulatory policies in both OPP and OGWDW must assure that the use patterns of 

the pesticides are managed and water supply contamination prevented so that drinking 

water suppliers are not left with the major responsibility to prevent or limit human risks. 

The primary control of human exposures and the potential public health impacts of 

pesticides and herbicides must reside with the producers, users, and applicators of these 

agricultural products. 

It is not clear how OGWDW will incorporate the risk assessments put forward by OPP in 

its Six-Year Review process, as there has been a fundamental difference in how the two 

offices have addressed these risk assessment issues in their own separate rulemakings. 

Essentially, OPP must conclude that the likely exposures do not exceed its level of 

concern and will therefore, approve the use of the pesticide. In contrast, OGWDW must 

establish MCLGs and MCLs. 
Docket EPA-HQ-OPP-2009-0759 

October 22, 2009 

Page 3 

Regardless on how the risk assessment is incorporated into rulemaking, when OGWDW 

issues an MCL, the usual quarterly monitoring regimen of chemical contaminants in 

drinking water may or may not be appropriate for these herbicides for surface water 

utilities in the Midwest because of the application occurs during a limited period of time 

during the year, and therefore, runoff will result in contamination in some watersheds 

during limited times. Seasonal or stratified monitoring may be (or may not be) necessary. 

Regulatory controls under OPP to address potential ecological effects may or may not 

result in any revisions to the atrazine drinking water standard. We are finalizing a paper 

to submit to a peer-reviewed journal of our multi-year statistical analysis of the atrazine 

monitoring data that should provide a foundation for future monitoring requirements, if 

OGWDW ultimately determines that the monitoring requirements need to be revised 

based on the final OPP risk assessment. 

It is not completely clear at this time whether OGWDW will revise some of the 

individual standards for the parent compound as part of it Six-Year Review process, 

develop standards for the degradation products, or develop a combined standard. EPA 

needs to clearly articulate how the agency plans to reconcile the differences in the risk 

assessment, regulatory development, and decision policies and processes between OPP 

and OGWDW. 

If you have any questions about these comments, please feel to call Alan Roberson or me 

in our Washington Office at 202-628-8303. 

Yours Sincerely, 

Thomas W. Curtis 

Deputy Executive Director 

cc: Peter Silva—OW 

Steve Owens—OPPTS 

Bob McNally—OPP 

Melanie Briscoe—OPP 

Cynthia Dougherty—OGWDW 

Pam Barr—OGWDW 

Ed Ohanian—OST 

Alan Roberson 

Steve Via 
Docket EPA-HQ-OPP-2009-0759 

October 22, 2009 

Page 4 

Peer-Reviewed Publications Resulting from Triazine Research 

• Graziano, N., McGuire, M., Adams, C., Roberson, A., and Blute, N. National 

Atrazine Occurrence Monitoring Program (2003) Using the Beacon ELISA 

Method. Journal AWWA, 98:10:111 (October, 2006). 

• Jiang, H., Adams, C., Graziano, N., Roberson, A., McGuire, M., and Khiari, D. 

Occurrence and Removal of Chloro-s-Triazines in Water Treatment Plants. 

Environmental Science & Technology (40:11:3609). 

• Jiang, H., Adams, C., Graziano, N., Roberson, A., and McGuire, M. Enzyme 

Linked Immunoassay Analysis (ELISA) of Atrazine in Raw and Finished Water. 

Environmental Engineering Science (23:2:357). 

• Graziano, N., McGuire, M., Roberson, A., Adams, C., Jiang, H., and Blute, N. 

2004 National Atrazine Occurrence Monitoring Program Using the Abraxis 

ELISA Method. Environmental Science & Technology (40:4:1163). 

• Adams, C., Jiang, H., McGuire, M., Graziano, M., Roberson, A and Frey, M. 

Accuracy and Interferences for Enzyme-Linked Immunoassay Tests for Atrazine. 

Journal AWWA, 96:12:126 (December, 2004). 

• Jiang, H., Adams, C., and Koffskey, W. Determination of Chloro-s-Triazines 

Including Didethylatrazine Using Solid-phase Extraction Coupled with Gas 

Chromotography-Mass Spectrometry. Journal-Chromotography-A, 1064:2:219.