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4.0 GROUNDWATER ANALYSIS 4.1 Description of the depth to groundwater, seasonal fluctuations of groundwater depth, directional flow and gradient: Description of depth to groundwater, seasonal fluctuations of groundwater,directional flow and gradient are referred to in Section 4 of the Soil Suitability Report prepared by Dillon& Murphy that is attached in the Appendix. 4.2 Description/discussion of any existing and/or potential groundwater contamination issues in the general location of the site: Description of existing or potential groundwater contamination issues in the general location of the site are referred to in Section 4.2 of the Soil Suitability Report prepared by Dillon& Murphy that is attached in the Appendix. 4.3 Description of the current use of groundwater at the site and of the future expected use of groundwater as related to the proposed development project: Based on the most recent results from San Joaquin County's "Flood Control and Water Conservation District"report on groundwater from fall 2017, the estimated depth to groundwater was determined to be 120 feet below the surface. This information is close to the data collected from the California Department of Water Resource's Water Data Library. The results of the historic depth to ground water show that the relative depth has not changed drastically throughout the years. The proposed improvements will not have a negative effect on the current depth to ground water. See appendix for the site's depth groundwater tables and diagrams. 5.0 SOURCES AND CALCULATED IMPACT OF NITRATE TO GROUNDWATER 5.1 Description of all current off-site sources of nitrate to soil and groundwater in the general up gradient area and the contribution of nitrate load from these sources to the project site: Current off-site sources of nitrate to soil and groundwater in the general up gradient area and the contribution of nitrate loads are agriculture and neighboring sites with septic systems with minimal to no current impact to the site. 5.2 Description of impact of rainfall contribution of nitrate load to the project site: The impact of rainfall contribution on the project site was completed to determine the nitrate load. The average monthly precipitation and evotranspiration are required to calculate the site nitrate load. These two values are used to estimate the deep percolation. The deep percolation is estimated by adding up the estimated monthly precipitation using 75%as a deep percolation rate.The estimated total precipitation for the year is (13.41 in) as done by (Crites and Tchobanoglous). The estimated monthly precipitations were obtained from Station 70 in the California Irrigation Management Information System (CIMIS) located in Manteca, CA. This is the closest active station to the project site and is still within the San Joaquin Valley and Zone 12. These calculations are attached in the Appendix. The results for the deep percolation at the site were 10.06 in./year. The nitrate concentration is estimated to be about 1 mg/L-N. (Hantzche and Finnemore, 1992).