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VI. CONCLUSIONS AND RECOMMENDATIONS From visual observations, there is no surface contamination from hazardous materials or hazardous environmental conditions. The location of the referenced small fuel tank that existed on the subject property prior to 1980 is unknown to Mr. Tony Silva's children and grandchildren, and therefore cannot be investigated. Given the length of time since tank removal (25+years), the indigenous clay soils with hardpan and the depth of groundwater of approximately 65 feet, make subsurface contamination and potential groundwater impact from any tank leakage extremely unlikely. Secondly, there is apparently no documentation as where the tank was located. Without direct knowledge of the precise tank location, it would be extremely difficult to conduct a subsurface soil investigation for residual contamination. Thirdly, the property is to remain in the Inman/Silva Family and not be sold or developed. Section 9-905.12 of San Joaquin County Development Title states "Corrective Action: If the report indicates there are surface and subsurface contamination, corrective action shall be recommended in the report and concurred with by Environmental Health prior to the issuance of the building permit." Therefore, it is my professional opinion that no corrective action is required on the two proposed Parcels composing the subject property. The septic system density is extremely low on the property and surrounding areas. A small portion of the property served as a dairy for approximately 40 years and still shelters cows. The cattle on the property are in extremely low numbers in comparison to the property acreage. Manure is periodically removed from the corral areas to prevent manure runoff. Consequently, the degree of nitrate-nitrogen impact from these two sources can be considered minimal. The soils under the subject Parcels have very limited percolation. Therefore, sumps or seepage pits must be installed to manage septic effluent. As referenced, given the low density of septic system in this locale and the clay soil structures, there may be a comparatively lower nitrate impact from existing and future septic systems. Given that agricultural irrigation recharge is the largest single contributor to groundwater nitrate concentrations, and since the surrounding land has been farmed for several decades, it is assumed that the nitrate concentrations in the underlying groundwater would be in much higher concentrations than what has been observed in this area. Consequently, attenuating factors must be significant. As noted on the Lines of Equal Depth groundwater map, the static groundwater depth is approximately 65 feet. The lines of Equal Elevation map shows the groundwater directional flow to be in a northwesterly direction. This groundwater directional flow places the DaSilva Dairy facility with a Leaking Underground Fuel Tank (LUFT) crossgradient to the subject property and makes impact from this LUFT extremely remote. The roads bordering the property and the areas adjacent to these roads should be patrolled on a regular basis to ensure there is no dumping of hazardous materials such as drug manufacturing chemicals. 6 / Chesney Consulting