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NOW ./ The science of pesticide residues in soil,air, surface water and groundwater is extremely complex and variable. Environmental models that attempt to predict pesticide behavior and transport in the f environment are beyond the scope of this investigation. Agricultural pesticide documentation was obtained directly from Mr. Boersma, who personally farms the property. He retains all pesticide application records to document applied materials every year. Materials are mixed on an adjacent property to the subject property. Mr. Boersma maintains an air gap between the hose nozzle and the tank contents while filling spray tanks. Available Environmental Fate Data for the pesticides used on the property for the past three years was obtained from the U.C. Davis and Oregon State University Extoxnet System, and is found in Appendix C. The Fate Data indicates most of the applied pesticides have comparatively short half- lives,other than Paraquat. As referenced below, although DDT was banned in 1972, its presence in San Joaquin Valley soils is indicative of its long half-life of 15.6 years. Consequently,there may be extremely small concentrations of DDT and its degradates in the subject property soils. The following chart summarizes the available Environmental Fate Data for the name and type of agrichemicals applied to the subject property. Noted times of duration are maximum values observed. The Fate Data is highly specific for various environmental conditions,and is normally expressed as half-lives in terms of days. In addition, the nitrogen fertilizer applied is 100-150 units of N, which is not excessive. PESTICIDE OR TYPE SOIL PERSISTENCE WATER FERTILIZER PERSISTENCE APPLIED TO THE PROPERTY (Common Name) Nitrogen Fertilizer Immediate plant uptake Unknown i Paraquat Herbicide 1000+days 13+hrs Surflan Herbicide 20-128 days Unknown Glyphosate Herbicide 1 - 174 days 12 -70 days Pesticides with long half-lives that may have been used or drifted onto the property decades ago,primarily DDT, may be of an extremely slight concern. DDT was used extensively throughout the agricultural fields of the San Joaquin Valley and degradates of DDT can be found in nearly all these soils. Previous Exposure Assessments made on typical San Joaquin Valley soils suggest an extremely low probability of adverse health effects from soil ' DDT/DDD and DDE concentrations (if the concentrations even exist). The environmental fate data are presented below for DDT, and its degradates DDD and DDE. Page -5- Chesney Consulting