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r�7�An important concern associated with the environmental assessment of agricultural properties is the issue of buried pesticide containers or discarded items. It was an occasional practice to dispose of containers by this method many years ago. To detect these types of underground artifacts is difficult even with the use of ground penetrating radar or other types of non-intrusive, subsurface analyses. The land surface did not exhibit visual indicators for buried containers such as surfacing of product residue, soil mounding or soil depressions. It is usually only after a contaminant plume has impacted a domestic well that pesticide containers are discovered. The static groundwater is found approximately 35 feet under the property as illustrated on the attached depth to groundwater map. This is considered a medium groundwater elevation. Deep groundwater cannot be easily impacted from pesticides or nitrogen in the form of nitrates. This is particularly true when there is intervening layers of clay soil down to the static water table depth. During our drilling procedures for the Soil Suitability Study; however,the soil profile to a depth of 12 feet consists predominately of sand. There is a hardpan layer which may have an attenuating effect on the downward migration of nitrates. The groundwater directional flow appears to be toward the northeast. Since the subject property has been in agricultural production for several years, an evaluation of environmental fate data for agrichemical residues as a nonpoint source of potential contamination was performed. The science of pesticide residues in soil, air, surface water and groundwater is extremely complex and variable. Environmental models which attempt to predict pesticide behavior and transport in the environment are beyond the scope of this investigation. It has been clearly evident over the last five decades that the risk/benefit ratio regarding pesticides has been overwhelming benefit and comparatively low risk to the United States population and the environment, as a whole. Environmental fate data for the following pesticides which may have been applied to the subject parcel are documented below. This list illustrates environmental fate data, indicating the half-lives are comparatively fast. Data was obtained from the Illustrated Handbook of Physical-Chemical Properties and Environmental Fate for Organic Pesticide Chemicals: CHLOROPICRIN. Common name: Nemax, Acquinite. Half-lives in the environment: Air: half-life 20 d by photodegradation. Groundwater: degradation time 4.3 h. Soil: Half-lives in loam are 1 d. Phytolysis: Under optimum exposure conditions to sunlight, half life is appro. 20 d. GUTHION. Common name: Azinphos-Methyl. Half-lives in the environment: Air: 12.6 hrs. Surface water: 3.2-200 hrs. Groundwater: 3.2-1440 hrs. Soil: 97-251 hrs in dry soil, 4458-4688 hrs in saturated soil. METASYSTOX-R. Half-lives in the environment: Air: 0.469-4.69 hrs. Surface water: 264-1344 hrs. Groundwater: 528-2688 hrs. Soil: 264-888 hrs. 4 Nafley Ag Research