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KL E/NFEL DER a„gni PaPA,qsoy„,,,, The online Web Soil Survey published by the U.S. Department of Agriculture, Natural Resources Conservation Service (2020) refers to the near-surface soil within the project area as belonging to the Stomar clay loam soil series (Map Unit Symbol 252). Stomar clay loam soils have a rating of"very limited”for septic tank absorption fields. Other attributes are given in the table below: Map Soil Name Available Water Capacity, pH Organic Content, Symbol cm/cm percent 252 Stomar clay 0.17 7.4 0.28 loam 4.4 GROUNDWATER Groundwater was not encountered in the boring drilled to about 23 feet for percolation test hole P-2. The California Groundwater Information Center Interactive Map Application (https://gis.water.ca.gov/app/gicima) indicates groundwater depths at the site greater than 100 feet below ground surface. Historic ground water data from between 1958 and 1976 indicates that groundwater measured in a well about 800 feet north of the project site was consistently deeper than 70 feet below ground surface. It is possible that groundwater conditions at the site could change due to variations in rainfall, withdrawal or recharge, construction activities, well pumping and irrigation, or other factors not apparent at the time the study was performed. We understand the existing water supply well on the D. Hill Trucking property will continue to be used to supply water for the development. No new wells are planned. The location of the water supply well is shown on Figure 2. The results of the groundwater analysis to determine the concentrations of nitrate (N) in the water sampled from the on-site well indicated a concentration of 1.8 mg/L. This nitrogen concentration is below the state drinking water standard of 10 mg/L. A copy of the test results and the chain- of-custody are presented in Appendix B. We do not know of any existing and/or potential groundwater contamination issues in the project vicinity. There are no gas stations adjacent to the property. The on- and off-site septic tank/leach field systems in the project area are probably the largest contributors of nitrates to groundwater in the project vicinity. 20210068.001A/ST020R110989 Page 6 of 14 April 30, 2020 ©2020 Kleinfelder www.kleinfelder.com