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n 3.1 Aquifer Information: Groundwater Depth, Direction of Flow and Flow Velocity NLS§ 2.1,2.3 Unfortunately, no well log exists for the on-site domestic, or irrigation well. The attached well logs from domestic wells to the south of the project illustrate potential water bearing strata and depth to the static water within the casing. These wells are approximately one mile to the south and the strata encountered may not be applicable to lithology under the property. However, it appears that the Corcoran Clay layer was encountered in all three wells, which extends from approximately 30 ft to 125 ft. The depth to first water in a recently drilled well one mile south of the property indicates a static water depth at 22 ft. This corresponds with the on-site domestic well measurement. However, the actual water table was encountered at 13 ft at this project one mile to south of the subject property. As referenced, no groundwater was encountered in the 15 ft backhoe test pits. Estimated Groundwater Gradient and Velocity SSS§4.1 According to the most recent Groundwater Lines of Equal Depth Map (1999)provided 3 by the San Joaquin County Flood Control District, the static water level under the center of the project is approximately 15 ft below grade. As referenced above, the on-site domestic well water depth was sounded at 22 feet below grade, which is the most probable water table depth. The 2003 Lines of Equal Elevation map illustrate the groundwater directional flow to be north- northeast, which has been confirmed in a nest of monitoring wells one mile to the south. Whether the gradient under the subject property flows northeasterly or westerly toward the San Joaquin i River is unknown at any point in time without highly sophisticated monitoring conducted over a number of years. The groundwater gradient is calculated below based upon the 2003 Lines of Equal Elevation Map. As the groundwater flow descends from the project site, the distance is estimated to be 10 ft 11,088 ft (2.1 mi) = 0.000902 ft/ft, which can be considered comparatively flat. The velocity of the groundwater directly downgradient from the subject site can be estimated by the following formula: I K(h,—h2) Vaquifa L 7.5 p Where: K=Hydraulic conductivity of aquifer formation in gals/day/ft2 =5000 gals/day/ft2 (est. based on a silty, medium sand formation) h,=0 ft hz= -loft L=2.1 mi= 11,088 ft 6 =porosity of aquifer z 37% (est.) Vaq,,;f,=0.91 ft/day The groundwater flow velocity is approximated to be 1 ft/day. Given that the property is 600 ft north to south, and if the directional flow is north to south, it may take groundwater approximately 1.6 years to flow under the N-S length of the property. Page -11- Chesney Consulting