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a chemical substance or mixture if it 'presents or will present an unreasonable risk of injury to health or 

 the environment.' Under section 4, EPA may require industry to test a chemical substance or mixture 

 if the agency finds it "may present an unreasonable risk of injury to health or the environment." If the 

 EPA decides that it lacks important information about toxicity or exposure, it can specify what 

 information the industry must provide through additional testing if necessary. 



Research on Transport and Transformation of Contaminants — In order to predict the movement of 

 contaminants in the subsurface, and thereby predict potential human and ecological exposure, EPA's 

 Office of Research Development (ORD) maintains a research program in transport and transformation of 

 contaminants. Some of this research is done to predict the leaching behavior of agricultural chemicals. 

 This includes advances in integrating process level information into predictive tools such as the pesticide 

 soils leaching model PRZM, the pesticide ground water leaching model RUSTIC, and the development 

 and application of the comprehensive environmental management model CEEPES to agricultural 

 chemicals. In addition, a new effort is underway to support the Office of Water in determining the 

 sorptive properties of soil as a factor in protecting wellheads from contaminant migration. 



EPA has joined with the United States Department of Agriculture (USDA) and the U.S. Geological 

 Service (USGS) in the Midwest Initiative on atrazine. Under a coordinated plan of study drafted in 1989, 

 the three agencies selected the mid-continent soybean and corn-growing region to determine the regional 

 factors affecting the distribution of atrazine, a herbicide of long-standing use, through the environment. 



Information Systems for Preventing Ground Water Contamination from Pesticides — Tools exist to 

 locate pesticide problem areas, and develop strategies for use of pesticides on a local level. These tools 

 include models that have been developed to predict the leaching of pesticides to ground water, data that 

 have been collected on soil properties and other relevant environmental factors, and geographical 

 information systems for displaying and analyzing spatial information. These types of tools, however, have 

 not been systematically integrated into a workstation framework of state and local risk management. ORD 

 has initiated research to provide such a framework for states upon which they can develop locally 

 meaningfiil pesticide management plans. The work will also include field evaluation and modeling 

 schemes. The project is coordinated with related research on the effects of agricultural chemicals on 

 water quality at USGS and USDA, in order to ensure integration of information and dissemination of 

 results. 



Methods for Assessing Aquifer Sensitivity to Pesticides — To assist states in assessing ground water 

 vulnerability to pesticides as part of their efforts to develop pesticide management plans, EPA's Office 

 of Ground Water and Drinking Water is preparing a technical assistance document on methods for 

 assessing the natural sensitivity of aquifers to pesticide contamination. 



President's Water Quality Initiative — The President's Water Quality Initiative (WQI), established during 

 the Bush Administration, called for a vigorous effort to protect ground and surfece water from 

 contamination by agricultural chemicals, commercial fertilizers, and wastes, especially pesticides and 

 nutrients. The WQI is using the combined expertise of USDA, USGS, EPA, and NOAA, to promote the 

 use of environmentally and economically sound farm production practices, and to develop improved 

 chemical and biological pest controls. 



Under the WQI, USDA has established the USDA Water Quality Program to determine the precise nature 

 of the relationship between agricultural activities and ground water quality; and develop and induce the 

 adoption of agrichemical management and agricultural production strategies that protect ground and 

 surface water quality. 



