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0 -_ 0 There is a storage shed near the SWC of the subject site (Lot 16), directly north of Harney Lane. This shed was inspected for hazardous materials and/or agrichemical storage. No hazardous materials were observed,. The only agrichemical storage consisted of several pallets and empty, bags of sulfur dust which is used for mildew control on the grapes. An important concern associated with the environmental assessment of agricultural properties is the issue of buried pesticide containers. 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. In addition, it is highly unlikely containers would have been buried on-site due to the past history of the property and the fact that there is a likelihood of severe hardpan under the soil surface. The static groundwater is found approximately 130 feet under the property as illustrated on the attached depth to groundwater map. This is considered a deep 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. Well logs were reviewed at the Environmental Health Department to ascertain underlying soil strata types. Although the closest well log was over one mile to the north, the soil strata consists predominately of clay strata. The groundwater directional flow appears to be slightly towards the northeast, to an area of recharge. Found in the Appendix is an Application Material Report listing all pesticides applied to the subject property for the crop year 1997 and 1998. Since the subject property has been in viticulture production for only a couple of years, an evaluation of agrichemical residues as a nonpoint source of potential contamination was not 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. The following is environmental fate data of the herbicides (except sulfur)which were applied to the subject property, as documented. This list illustrates environmental fate data, indicating the half-lives are comparatively fast. Data, if available,was obtained from the Illustrated Handbook of Physical-Chemical Properties and Environmental Fate for Organic Pesticide Chemicals: 3 vaffey Ag Pfsearch