SR0081147_SSNL & OWTS - Laserfiche WebLink

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GROUNDWATER INFORMATION NLS§ 2.1, SSS§ 4.1, SSS§ 4.4. Groundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. However, due to the known high water table in this locale since it is at the southern edge of the Delta, a backhoe test pit was dug to determine water table depth. After several hours of stabilization, the water table was measured at 5.7 ft below grade. This can be considered the highest elevation of the year due to irrigation recharge. Consequently, the leachfield must be constructed at-grade to maintain a five-ft separation distance between the soil-effluent interface and the depth to the water table. NLS§ 2.3, SSS§ 4.3, 4.5, 4.6. There is one well on the subject Parcel as noted on the attached Design Site Plans. Construction details of the well are unknown. Currently, a surface pump is used to draw water kr watering the animals and for the sampling/testing for this report. The pump was run for 20 minutes before sampling. Samples were refrigerated and then transported under attached Chain of Custody. A new submersible pump will be installed under permit, at which time re-sampling, testing and analysis will be completed. The following Table illustrates the test results for constituents tested from the water well and the backhoe test pit water. TABLE 3 WELL WATER AND WATER TABLE ANALYTICAL RESULTS OF TESTED CONSTITUENTS SAMPLE ID NITRATE AS NITRATE TOTAL KIELDAHL NITROGEN (TKN) DBCP TOTAL ALKALINITY Ec PH Well Water 0.880 mg/L . 4.76 mg/L ND 189 1.6 7.4 Groundwater 5.67 mg/L _ <0.5 -- -- 7.1 NLS§ 2.2, 3.1, SSS§ 2.1, 4.2. Since the subject property and surrounding properties have been under agricultural production for a number of decades, the potential for nitrate contamination to the underlying groundwater could be considered significant. However, this not observed. Additionally, the well water alkalinity is low, thus impeding nitrification. Somewhat elevated TKN concentrations have been routinely observed in areas of the Delta and can be attributable to historical organic matter decomposition. SURFACE WATER INFORMATION Storm water drainage management will be on-site due to the large surrounding open area. Since the Ag Building and the Abattoir will not constitute a commercial business since no resale will be conducted, a storm water permit is not required. Page -4- Chesney Consulting