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Q 4.0) LOCAL GROUNDWATER AND SURFACE WATER INFORMATION (§ 4.1) Static groundwater is found approximately seven feet under the property. This is based upon water observed in the adjacent unlined irrigation canals and laterals. The 1999 Lines of Equal Depth to Groundwater map and the 1999 Lines of Equal Elevation of Groundwater do not illustrate the groundwater depth or directional flow in the Delta region. From recent groundwater studies done at a nearby dairy, it is known that the groundwater directional flow is to the east and southeast, although this is surely influenced by tidal action. A groundwater depth of seven feet or less, can be considered a very shallow groundwater elevation, and a water table determination must be conducted if there is an application to build on the subject property. The Delta area obviously has heavy peatland soils, as discussed below, that may impede agrichemical impact and possibly promote denitrification. No Well Drillers' Logs for nearby domestic wells were found in the microfiche files at EHD. Therefore, the underground lithology surrounding the subject property could not be discerned. From other well drilling projects in the Delta region, it is known that sand and clay compose underlying strata. The property is in the Flood Zone and subject to flooding, with the flood elevation at 8 feet. Surface water runoff from the residential structure and metal building is diverted into the surrounding cropland. (§ 4.3 and 4.5) The on-site domestic well is located adjacent to the north of the referenced metal building. This well was sampled on October 29, 2008 after the pump was operated for 15 minutes to insure that well casing water and tank water had been purged. A nitrate water sample was drawn into a one-half liter plastic bottle and the DBCP sample was drawn into three VOC glass vials. (§ 4.5 and 4.6) All samples were placed in a cooled ice chest and transported to A &L Labs in Modesto under the attached Chain of Custody found in Appendix B. Due to an extraordinary turnaround time for the DBCP analysis, test results were received on December 18, 2008 (§ 4.4) Water analysis results reveal a high nitrate concentrations in domestic wells at 123 ppm. The Maximum Contaminant Level (MCL) for nitrate in drinking water is 45 ppm. DBCP was Below Detectable Limits (BDL). A summary of the test results are illustrated in Table 2, below. (§ 4.2) Considering the area has been intensely farmed for the past several decades, these nitrate concentrations were to be expected in the tested well. TABLE 2 WELL WATER ANALYSIS WELL ANALYTE CONCENTRATION MAXIMUM CONTAMINANT LEVEL I FOUND Domestic Well Nitrate(As Nitrate) 123 ppm 45 ppm DBCP BDL 0.2µ/, Page -4- Chesney Consulting