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APPENDIX <br /> GROUNDWATER DIRECTION AND FLOWTE CALCULATIONS <br /> The groundwater monitoring network consists of eight monitoring wells and a piezometer. Two <br /> water-bearing zones are monitored. To monitor the shallow,perched aquifer, MW-4, MW-5; <br /> SB-1, PZ-1, MW-8 MW-9A, MW-10A, MW-11A are used. Well SB-1 was originally installed <br /> to provide additional water level data. SB-1 was added to the monitoring well network on <br /> December 2, 1996. Piezometer PZ-1 was added July 30, 2003. Water elevations taken at these <br /> five points are used to define the direction and gradient of groundwater flow in the vicinity of <br /> CHLF. The average groundwater velocities in this water bearing zone were calculated using the <br /> following equation(Darcy's Law): <br /> V= Ki <br /> n <br /> V=maximum linear velocity <br /> K=permeability <br /> i =hydraulic gradient <br /> n =porosity <br /> K= 8.1 lx 10-5 centimeters per second(cm/s) <br /> = 83.69 feet per year (ft./yr) <br /> i = 0.026 foot per foot(ft/ft) northeasterly <br /> n =0.30 <br /> The northeasterly groundwater flow velocity of about 7.439 ft/yr was calculated as follows: <br /> V = 83.69 ft/yr(0.026 ft/ft) = 7.439 ft/yr <br /> 0.30 <br /> The hydraulic conductivity was determined with a slug test in well MW-4 to be 8.11 x 10-5 cm/s <br /> in the perched water-bearing zone beneath the landfill. An average porosity value of 0.30 was <br /> used, based on published porosity values for similar geologic materials. <br /> The deep water-bearing zone is monitored by wells MW-1, MW-2,MW-6, and MW-7. Wells <br /> MW-1 and MW-2 were dry. MW-6 and MW-7 were installed in 2003 and water elevations were <br /> used to calculate groundwater flow and generate a groundwater contour map. The average <br /> groundwater velocity was also calculated using the equation based on Darcy's law: <br /> K= 8.11 x 10-5 centimeters per second (cm/s) <br /> = 83.69 feet per year(ft./yr) <br /> i = 0.004 foot per foot (ft/ft)northeasterly <br /> n =0.30 <br /> The northeasterly groundwater flow velocity of about 1.115 ft/yr from well MW-7 to MW-6 was <br /> calculated as follows: <br /> V = 83.69 ft/yr(0.004 ft/ft) 1.115 ft/yr <br /> 0.30 <br /> Corral Hollow Sanitary Landfill G-1 Department of Public Works/Solid Waste <br /> 1 s'Quarter 2014 Groundwater Monitoring County of San Joaquin—March 15,2014 <br />