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Rule 2: Permits <br />established in the region by Howard (1982). A map of the potentiometric surface of this unit is <br />included as Map 2.04.7-5. <br />Characteristics of the Primero were determined via slug testing. A slug test was performed in well <br />MW~-C, and recovery of the well to static was not accomplished in 17 hours of data collection. <br />Approximately 65 percent of the recovery did take place in this time. This indicates an extremely <br />low hydraulic conductivity for the Primero. Estimated hydraulic conductivity as determined via <br />this testing was 1.22 x 10-' ft/day. This value can be translated to transmissiviry (T) by the <br />equation T = Kb, where T is transmissiviry, K is hydraulic conductivity, and b is the aquifer <br />thickness. Therefore: <br />T=Kb <br />T = (1.22 x 10"' ft/day) (5 ft) <br />T = 6.10 x 10-' fc~/day or 4.56 g/d/ft <br />Comparing this to the regional values: <br />T=Kb <br />T = (0.0408 ft/day) (5 ft) <br />T = 0.204 ft2/day or 1.53 g/d/ft <br />• Comparing this value to the established values determined in the regional srudy by Howard (1982), <br />this value is slightly higher. Based upon field data from bailing the wells at the site, the value <br />determined from site specific and regional data slug test would appear low. The potential pumping <br />rate from the well can be estimated from the equation Q=Ts/2000 (derived from Fetter, 1980). <br />In this calculation Q is the flow rate, T is the transmissivity (determined from the hydraulic <br />conductivity T=K6), s the available drawdown, and 2000 is a constant (accounts for conversion <br />of T in g/d/ft). Therefore: <br />Q = 4.56 g/d/ft [221 ft (for MW-4C)]/2000 <br />Q = 0.50 gpm (for site-specific data) <br />Q = 1.53 g/d/ft [221 ft (for MW~C)]/2000 <br />Q = 0.169 gpm (for regional data) <br />Generally, the rate of evacuation for the wells during the sampling events is estimated as 1.0 gpm. <br />This value and the potential pumping rate for the well (determined above utilizing site-specific <br />data) compares more favorably; therefore the range of the transmissivity in this zone is 0.169 <br />g/d/ft to 4.56 g/d/ft. <br />Storativity estimated by this method (Cooper, Pappadapoulous) was 9.93 x 1(16. Both values are <br />within acceptable ranges for a confined zone (Heath, 1983). The hydraulic conductivity <br />• <br />PERMIT.d]6\Darmber Z0, 1996 2.04-18 <br />