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4.0 GROUNDWATER ANALYSIS <br />4.1 Description of the depth to groundwater, seasonal fluctuations of groundwater depth, <br />directional flow and gradient: Description of depth to groundwater, seasonal fluctuations of <br />groundwater, directional flow and gradient are referred to in Section 4 of the Soil Suitability <br />Report prepared by Dillon & Murphy that is attached in the Appendix. <br />4.2 Description/discussion of any existing and/or potential groundwater <br />contamination issues in the general location of the site: Description of existing or potential <br />groundwater contamination issues in the general location of the site are referred to in Section 4.2 <br />of the Soil Suitability Report prepared by Dillon & Murphy (See Appendix). <br />4.3 Description of the current use of groundwater at the site and of the future expected use <br />of groundwater as related to the proposed development project: Based on the most recent <br />results from San Joaquin County's "Flood Control and Water Conservation District" report on <br />groundwater from Spring 2018, the estimated depth to groundwater was determined to be <br />160-170 feet below the surface. This was verified with the California Department of Water <br />Resource's Water Data Library. The results of the historic depth to ground water show that the <br />relative depth has not changed drastically throughout the years. It fluctuates minimally on a <br />yearly basis. The proposed improvements will not have a negative effect on the current depth to <br />ground water as the proposed usage is less than that of agriculture. See appendix for the site's <br />depth groundwater tables and diagrams. <br />5.0 SOURCES AND CALCULATED IMPACT OF NITRATE TO <br />GROUNDWATER <br />5.1 Description of all current off-site sources of nitrate to soil and groundwater in the general <br />up gradient area and the contribution of nitrate load from these sources to the project <br />site: Current off-site source of nitrate to soil and groundwater in the general up gradient area and <br />the contribution of nitrate loads are agriculture and neighboring sites with septic systems with <br />minimal to no current impact to the site. <br />5.2 Description of impact of rainfall contribution of nitrate load to the project site: The <br />impact of rainfall contribution on the project site was obtained to determine the nitrate load. The <br />average monthly precipitation and evapotranspiration are required to calculate the site nitrate <br />load. These two values are used to estimate the deep percolation. The deep percolation is <br />estimated by analyzing the difference between the monthly average precipitation and the <br />evapotranspiration when the evapotranspiration exceeds the monthly average precipitation. The <br />available evapotranspiration was adjusted with an adjustment factor based landscaping on-site. <br />These calculations are attached in the Appendix. The calculations were done for the proposed <br />3.98 acre Financing Parcel and 83.43 Designated Remainder Parcel. <br />The data for the potential evapotranspiration water was obtained from the California Irrigation <br />Management Information System (CIMIS). The project is located within an area designated as <br />Zone 12. Based on the values for this area along with the average monthly precipitation values <br />obtained from the Western regional Climate Center (Station 262) for the Linden region an <br />estimate of the deep percolation of rain for the project was determined. <br />OA <br />