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'r From previous nitrate loading and soil suitability studies done to the northeast, it is known that there gajhbg high *�n�entrations of nitrate in the underlyin¢dri^k;^� �uatrr ag�, uifers. However, it appears that nitrate levels over the Maximum Contaminant Level (MCL) have been the result of localized conditions,mainly due to nitrogen fertilizer spills. As noted on the attached Environmental Questionnaire, 150 units (pounds per acre) of nitrogen have been applied to the trees, per year. According to the Western Fertilizer Handbook published by the California Fertilizer Association, 200 pounds per acre are required of mature almond trees to produce an acceptable crop. Since there is organic material in the soil to provide an Estimated Nitrogen Release (ENR)that would supplement the applied N units, 150 units of nitrogen is probably a very accurate amount of nitrogen to apply. PUBLIC ENVIRONMENTAL RECORD/DATA SOURCES Static groundwater is found approximately 25 feet under the property as illustrated on the attached 2000 Lines of Equal Depth to Groundwater map. From the 2000 Lines of Equal Elevation of Groundwater,the groundwater directional flow appears to be toward the northeast. A groundwater depth of 25 feet can be considered a relatively shallow groundwater elevation which can be impacted from serious point source releases and to a somewhat lesser degree from agrichemicals such as pesticides, herbicides, or nitrates from fertilizers. The degree of impact from agrichemicals is particularly mitigated when there are intervening layers of clay or hardpan soil down to the static water table depth. It is known that a hardpan layer exists in this locale. Based upon personal communication with Doug Wilson of the Environmental Health Department, there are no records of above ground, or under ground (AST/UST) storage tanks at the subject property address. This is also illustrated on the attached GeoTracker Site Map, which shows no tanks near the site. A Leaking Underground Fuel Tank(LUFT) site is shown at the Gaging Station, 5,000 feet north of the property. This Gaging Station can be considered downgradient to the site. Potential environmental impacts from past, present or future facilities within a one mile radius is unknown at this time,but unlikely. Two sources of information which attempt to document and define on-site and surrounding past land use were also utilized. The first is the use of aerial photographs. Aerial photographs of the subject area from 1970 through 1977 found on USDA Soil Maps reveal the property to be the same as it currently is. The aerial photo shows that there appears to be no buildings on the property. The USDA Soil Map shows the soil to consist of a Honcut sandy loam (#175). Typically, these soil types are well drained with moderate permeability,which is a beneficial soil attribute for septic effluent management. There are sufficient soil "fines" to impede rapid percolation so treatment of effluent can occur before reaching the water table,unlike what would be encountered with a very sandy soil. The second source of information can be found on USGS maps. The property is on the border of the Manteca Quadrangle map, which is found in the Appendix. Page-3- ClestteY Consulting