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L. <br /> FFAgricultural spray drift (non-target) from the nearest agricultural production land affecting <br /> roperty could be a possibility, since agricultural production occurs all around the <br /> ct property. The region has been, and continues to be intensely farmed, so nitrate <br /> amination to the underlying groundwater from nitrogen fertilization is always a <br /> possibility. The agrichemical DBCP has been also detected in this locale. <br /> The science of pesticide residues in soil, air, surface water and groundwater is extremely <br /> complex and variable. Environmental models that attempt to predict pesticide behavior and <br /> transport in the environment are beyond the scope of this investigation. <br /> Agricultural pesticide documentation was obtained directly from the farmer, Mr. Gary <br /> Winters, who custom farms the property. He retains all pesticide application records to / <br /> document applied materials every year. Materials are mixed on-site, at the domestic well <br /> site. As noted in the attached photographs, there is a backflow prevention device on the <br /> water hose. In addition, Mr. Winters maintains an air gap between the hose nozzle and the <br /> tank contents while filling the spray tank. <br /> Available Environmental Fate Data for the pesticides used on the property for the past three <br /> years was obtained from the U.C. Davis and Oregon State University Extoxnet System, and <br /> is found in Appendix C. The Fate Data indicates most of the applied pesticides have <br /> comparatively short half-lives, other than Paraquat. As referenced below, although DDT was <br /> banned in 1972, its presence in San Joaquin Valley soils is indicative of its long half-life of <br /> 15.6 years. Consequently, there may be extremely small concentrations of DDT and its <br /> degradates in the subject property soils. <br /> The following chart summarizes the available Environmental Fate Data for the name and <br /> type of agrichemicals applied to the subject property. Noted times of duration are <br /> maximum values observed. The Fate Data is highly specific for various environmental <br /> conditions, and is normally expressed as half-lives in terms of days. In addition, the <br /> nitrogen fertilizer applied is 150 units of N,which is not excessive. <br /> Page -5- <br /> Chesney Consulting <br />