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PERCOLATION TEST yRE.SULTS PPERCDEPTH WEST PARCEL - MIDDLE PARCEL EAST PARCEL H PERC RATE PERC RATE PERC RATE 35.7 min/in @ 42 Inch Depth 41.7 minlin @ 42 Inch Depth Failed @ 42 Inch Depth TE No Pere Test Conducted at the 13.0 min/in @ 10.2 Ft.Depth Failed @ 8 Ft.Depth C H Intermediate Depth - Failed @ 23.5 Ft.Depth 5.0 min/in @24.5 Ft.Depth 7.3 min/in @ 24.5 Ft.Depth H (Possibly due to cave-in) III. NITRATE LOADING STUDY RESULTS A. GROUNDWATER INFORMATION 1. GROUNDWATER GRADIENT, VELOCITY AND ANALYSES The static water level under the center of the project is located approximately 73 feet below grade according to the 1999 Lines of Equal Depth Map published by the San Joaquin County Flood Control District. 'The 1999 Lines_ofEqual Elevation map illustrate the groundwater to be approximately -25 ft MSL. The 1992 Lines of Equal Elevation map illustrates the groundwater to be -62 ft MSL. Therefore, the static groundwater level appears to have risen 37 feet in the past seven years. �-/ Current groundwater directional flow is in a north-northeasterly direction according to the Lines of Equal Elevation Contour map.. From this map,.it appears the gradient is to the north-northeast under the property, and then changes to an east-northeasterly direction south of the property. The 1992 Equal Elevation Map indicates the groundwater flow to the north-northwest due to apparent heavy groundwater pumping in this area. The groundwater gradient under the subject site is estimated to be -20 ft - (-30 ft)- 5,800 ft j� 0.00172 ft/ft,based on the distance between-contour lines under the property. The velocity of the top groundwater formation under the-site can be estimated by the following formula: Kms,-12A Vaquifer L 7.5 p l Where: K=Hydraulic conductivity of aquifer formation in gals/day/fF ;z500 gals/day/ftz (Estimated based on a silty clay formation denoted on well log for 7425 Orford Road below the 70-foot depth.) h,_ -20 ft h2= -30 ft L= 5,800 ft p = porosity of aquifer z 35% (estimated) Vaquifer=2.3 ft/day or 840 ft/yr Chesney Consulting-