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t 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 20 feet under the property as illustrated on the attached depth to groundwater map. From the results of the Nitrate Loading Study, the groundwater directional flow is toward the northwest. A groundwater depth of 20 feet can be considered a shallow groundwater elevation. Shallow groundwater can be easily impacted from pesticides or nitrogen in the form of nitrates. This is particularly true when there are no intervening layers of clay soil down to the static water table depth. However, during our drilling procedures for the Soil Suitability Study; the soil profile to a depth of 12 feet consists lifedominately of silty sand/sandy silt with a hardpan layer at approximately four feet below grade: This layer may have an attenuating effect on the downward migration of nitrate molecules. Since the subject property has been in agricultural production, an evaluation of environmental fate data for agrichemical residues as a nonpoint source of potential contamination was done. 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. II E Environmental fate data for the pesticides applied to the subject property is documented below. For agrichemicals with available environmental fate data, the list indicates the half-lives are comparatively fast. Data was obtained from the Illustrated Handbook of Physical-Chemical Properties and Environmental Fate for Organic Pesticide Chemicals: ROUND-UP. Common name: Glyphosate. Half-lives in the environment: Air: Unknown. Surface water: Half life> 9 wks. Groundwater: Unknown. Soil: <60 d. DIAZINON. Photooxidation: 4.1 hr. Surface water: 43 d. Soil:12 wks. ROVRAL. Data Not Available, but probably similar to Captan. CAPTAN. Half-lives in the environment: Air: 2.6 hrs. Surface water: 170 min. Groundwater: 10.5 min. Soil: 40-1440 hrs. OMITE. Data Not Available. Fertilizers are water run through the flood irrigation system, with the proper amounts for almond tree uptake, thus preventing excessive leaching past the root zone. 4 - Vafky Ag.research