Laserfiche WebLink
33503 S Koster Road Project No. 2021-00073 P a g e | 4 <br />ground water aquifers. Therefore, soils of this type typically present a low risk of excessive <br />mass transport of nitrate or other constituents of concern. <br />4.0 GROUNDWATER INFORMATION <br />4.1 Groundwater Depth and Gradient <br />The San Joaquin County Flood Control and Water Conservation District (2017 and 2018) <br />groundwater reports were reviewed to determine the groundwater levels near the Site. The <br />Fall 2017 and Spring 2018 maps are the most current official maps available from the <br />County. According to these maps, (Plates 5 and 6) in Appendix A, groundwater elevation is <br />approximately 45 and 55 feet below mean sea level (msl) in the fall and spring, respectively. <br />The elevation of the land, as previously mentioned in Section 1.1, is approximately 125 feet <br />above mean sea level. Therefore, the depth to groundwater (the difference between the <br />elevation of the Site and the elevation of groundwater), is approximately 80 and 70 feet <br />below the ground surface (bgs) in the fall and spring, respectively. The groundwater in the <br />vicinity of the Site appears to flow to the northeast, at a gradient of approximately 10 feet <br />per mile. <br />No groundwater was encountered by the staff of Petralogix, Inc. during the shallow <br />percolation test hole auguring on September 6, 2021. <br />4.2 Potential Groundwater Contamination Issues <br />No above- or below-ground off-site potential or known sources of contamination were <br />identified from current uses of the surrounding properties, except for the following: <br />Surrounding properties are used for agriculture; agricultural chemicals may be <br />applied to these properties. <br />The site and surrounding properties utilize septic systems. <br />The Site is located within an agricultural region; groundwater contamination can result from <br />activities related to farming practices where chemicals are applied to crops which may <br />permeate to groundwater. The site and surrounding properties utilize septic systems; <br />leakage from septic tanks or failed septic systems can introduce bacteria to groundwater. <br />4.3 Water Sample Locations and Constituents <br />A domestic well groundwater sample was obtained from the site on September 7, 2021 by <br />Tonya Scheftner. Laboratory supplied containers, an ice-chest, ice, chain-of-custody <br />documentaion, and sampling equipment (plastic gloves, plastic bags) were obtained prior to <br />sampling. The sample was collected after flushing the system with a reduced steady stream <br />for a minimum of five minutes. No filtration system was observed or reported.