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PERCOLATION TEST RESULTS SHALLOW PERC TEST PERC RATE IN DEEP PERC TEST PERC RATE IN MIN/INCH MIN/INCH Shallow (42 in.) 3.7 min/in I Deep(25 ft) 3.6 min/in III. NITRATE LOADING STUDY RESULTS A. GROUNDWATER INFORMATION The static water level under the center of the project is located at approximately 75 ft below grade according to a newly constructed well at the Calaveras Cement Company, directly east of the subject site. The Lines of Equal Depth Map and the Lines of Equal Elevation map published by the San Joaquin County Flood Control District do not illustrate the groundwater depth and elevation in the Tracy location due to immense variability. From prior studies conducted, particularly at the Tracy Army Depot and the topography of the land surface, it is known the upper zone groundwater(above the Corcoran clay layer) flows in a northeast direction. From groundwater studies conducted by the United States Geological Survey (USGS), Lower zone water(under the Corcoran clay) flows in a west-northwesterly direction. Two wells of known nitrate concentration are referenced below. The cattle yard well is upgradient to the site approximately five miles and the cement company well is crossgradient approximately one-half mile. Interestingly, these two wells have almost identical nitrate concentrations: NITRATE CONCENTRATIONS - UPGRADIENT AND CROSSGRgDIENT NITRATE CONC.CATTLE YARD NITRATE CONC.CALAVERAS WELL CEMENT WELL 26 ppm as NO, 25 ppm as NO, B. SURFACE WATER INFORMATION LLbe ace water consists of all other water sources originating on the surface of the project, other septic system effluent. These sources include rainfall, surface runoff, and stormwater ntion. The San Joaquin County of Public Works - Isohyetal Map show 13inches of rainfall to he Mean Annual Precipitation in the area of the project. Page -4- Ch mq Consulting