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<br />Comparing this to the regional values: <br />Lorencila Cam~on Mint - Groundw•aler Technical <br />T=Kb <br />T = (0.0408 ft/day) (5 ft) <br />T = 0.204 ft~/day or 1.53 g/d/ft <br />Comparing this value to the established values determined in the regional study by Howard (1982) <br />(Table GW-7), this value is slightly higher. Based upon field data from bailing the wells at the <br />site, the value determined from site specific and regional data slug test would appear low. The <br />potential pumping rate from the well can be estimated from the equation Q=Ts/2000 (derived <br />from Fetter, 1980). In this calculation Q is the flow rate, T is the transmissiviry (determined from <br />the hydraulic conductivity T=Kb), s the available drawdown, and 2000 is a constant (accounts for <br />conversion 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-4C)]/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 />Storativiry estimated by this method (Cooper, Pappadapoulous) was 9.93 x 106. Both values are <br />within acceptable ranges for a confined zone (Heath, 1983). The hydraulic conductivity <br />determined was one order of magnitude lower than the value determined by Howard (1982) for <br />the Raton Formation coals. <br />Groundwater seepage velocity (v,) can be determined from the gradient (dh/dl, or I), effective <br />porosity (rte, and hydraulic conductivity (IC). Seepage velocity represents the rate at which water <br />actually moves through the pore spaces. The relationship vs=Ki/ne, is utilized to determine this <br />value (Fetter, 1980). From the above analyses: <br />K = 1.22 x 10l ft/day (for site specific tests), 0.0408 ft/day (for regional values) <br />I = 0.0078 ft/ft <br />4=10% <br /> <br />GroundwarcrA76\Deccmber 9. 1996 43 <br />