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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 Spring 2018, the estimated depth to groundwater was determined to be 90 feet below the surface. This was confirmed with the California Department of Water Resource's Water Data Library which showing similar groundwater levels to the San Joaquin County's Ground water report. The results of the historic depth to ground water show that the relative depth has not changed drastically throughout the years. The proposed improvements may affect the current depth to ground water as the site project will require water services, although the lots will be served by the San Joaquin County (CSA 29) and not require private wells. 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 source of nitrate to soil and groundwater in the general up gradient area and the contribution of nitrate loads are agriculture neighboring agriculture and neighboring home sites with septic systems with minimal to no current impact to the site. The neighboring sites are all residential/agricultural with no major sources of pollution that could affect this project site. The site was formerly used as a dairy and the development could reduce the nitrates from historical levels. 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 analyzing the difference between the monthly average precipitation and the evotranspiration,when the evotranspiration exceeds the monthly average precipitation. These calculations are attached in the Appendix. 2