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Potential Groundwater Contamination Extensive water quality tests were conducted for the City of Tracy well (2,500 I.f. northwest of the project site). A multi-completion monitoring well was constructed to collect water quality samples at various depths. General mineral, physical,and inorganics were tested, indicating no results exceeded primary drinking water standards. TDS and some salts did exceed secondary standar . No organic contaminants were tested. Nitrate(NO3) ranged fr 6.3 I (upper zone at 370' 4.5 m (lowest zone at 550'). Water data was also collected from the well located at the project site (see below). Test results show several secondary drinking water standards exceed MCL's(TDS,chloride, sulfate, iron),and one primary drinking water standard (hexavalent chromium). Nitrate data collected from January, 2010 throughl November, 2016,show that nitrate is present, ranging from approximately 5 mg/j-N to 8.5 mg/1-N. However, data shows no clear trend in nitrate concentrations,so nitrate concentrations alfpears-stable at this time. On-Site Wells A small domestic well is used for drinking water for the existing warehouse(SJCEHD identified as Schulte Road Warehouse Water System, 15000 W.Schulte Road,APN209-24-025). 3 The well driller's report indicates the well was constructed in 1990, is 400'deep with perforations between 300'and 400' below grade, and a 10" casing. The proposed project will construct a small 8"well for potable water use in the building, and irrigation of low-water use plants and groundcover. Projected water demands are projected to range from approximately 5 gallons per minute (winter)to 40 gallons per minute(summer). A larger 16"fire suppression well is also planned for, but the groundwater demands are almost zero. Water Samples The water system is regulated by SJCEHD. Water quality data for this well has been previously submitted to and on file with County EHD. Soil Profile and Geologic Information Extensive soil investigations were conducted at the site in 2016. A soil boring was conducted near the proposed leach field to a depth of 16.5'. The report indicates that soils consist of a mixture of sil'is, sands,and clays. See Figure 1. Soil chemistry and texture were analyzed by an independent laboratory. The soil sample was taken at the proposed leach field area from a depth of approximately 3'. Test results indicate very low concentrations of nitrogen in the soil and neutral pH of 7.12. The laboratory test results are provided in 3 Actual parcel address is 14700 W.Schulte Road,Tracy,California(APN 209-240-034). LBA Nitrate Loading Study/Jan 2017 pg. 2