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r�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. It is usually only after a contaminant plume has impacted a domestic well that buried pesticide containers are usually discovered. Because the majority of the property has been excavated, the probability is high that subterranean objects would have been discovered. Additionally, due to the high water table, it is highly unlikely this practice occurred in this locale. No petroleum or natural gas pipelines traverse the property; however, there are PG&E easements. The Mobile Home Park to the northeast has had extensive problems with its sewage system. Raw sewage had been spilling onto the subject property. This discharge has since been stopped and there has not been a release for several months. As noted at the south end of the USGS map, there are sewage disposal ponds 1.5 miles to the southwest of the subject property. These ponds can be considered upgradient from the site, but due to the distance involved, it is unlikely impact has occurred to the property. The static groundwater table is found approximately 8 to 12 feet under the property. This is considered a very shallow groundwater elevation and may be easily impacted from nitrates and/or agrichemicals. The soil profile to the depth of groundwater consists clay and silt or sandy loams, depending on the soil type as denoted on the soil map. Intervening layers of the heavier clay and silt soils down to underlying aquifers can attenuate possible impact from adverse constituents better than sandy soils. Underlying clay strata are illustrated on the attached well log. Since an artificial lake has been created from the dredging process, the subject property is a zone of groundwater recharge. Groundwater directional flow is influenced by this artificial lake. However, from a regional standpoint,the flow direction appears to be very slowly toward the San Joaquin River, as denoted on the attached lines of equal elevation groundwater map. Although 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 should not be performed since the property is still undergoing significant changes. 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 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 to the environment, as a whole. With recent advances in fertilizer application technology and awareness of input economics, it is assumed that fertilizers are applied carefully to the surrounding acreage with the proper techniques and controls such as soil and leaf tissue analyses. This allows for an equal distribution of nitrogen, phosphorous and potassium (NPK) for crop uptake, thus preventing excessive leaching past the root zone. 4 Va(�ey Aq Research