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Environmental fate data for the herbicide Round-Up®applied to the subject parcel is documented below and illustrates the half-life is 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. CONCLUSIONS AND RECOMMENDATIONS From visual observations,there is no surface contamination. The probability of subsurface contamination from pesticides can be considered extremely low-to-nonexistent, considering the environmental fate data for Round-Up®,the soil type, and the fact that pesticides have not been applied to the farmable acreage for over a decade. Therefore, at this point in time, no corrective action is required within the boundaries of the subject property. If there were a petroleum release from the Chevron Banta Facility that impacted the subject property, this would obviously be the responsibility of Chevron Oil Company to mitigate. The domestic well that serves the Pombo's residence will be tested for nitrate and DBCP to complete that part of the Soil Suitability Study. Further information on this well will be addressed in the Soil Suitability Study. Therefore, at this point in time,we do not recommend the well water be tested for a multi-residue pesticide screen consisting of analysis for Dinitroanaline, Triazine, Organochlorine and Organophosphates. I Regardless of the nitrate concentration of the groundwater, it is recommended that bottled water be used for drinking and cooking in areas that have domestic wells in intensely farmed regions. It is our opinion that contamination originating from the existing septic tank and leachfield is a very slight possibility because the leachfield may be upgradient from the on-site domestic well. However, the precise groundwater directional flow cannot be determined without sophisticated groundwater monitoring, which is not recommended. Another factor to consider is the influence the weight of the house pad would have on ground water flow. It may be a possibility that the highest, or most shallow groundwater flows "around" the weight distribution of the house pad. Contamination from a septic tank is usually dependent upon the age and type of tank construction material. Since the tank is comparatively new and should be watertight,there should be no problems with infiltration. The density of septic systems in the surrounding area Lalsoonsidered extremely low. The density of septic systems is one of the primary trate contamination originating from septic effluent, of the underlying groundwater. Pae -4- Nadey Ag Research