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• stones. Due to the migration of groundwater down dip from its <br />recharge area along the crest of the anticline and the confining <br />nature of the shaley siltstones, water is under artesian head when <br />encountered at depth during drilling. Water levels in drill holes <br />that penetrate these confined aquifers will rise in response to the <br />hydrostatic head until the equilibrium level is reached. This <br />equilibrium level is a function of the elevation of the recharge <br />area, the permeability of the sand unit and the confining ability <br />of adjacent strata. <br />Aquifer Characteristics. <br />Previous analyses for Pit 1 outlining the hydraulic character- <br />istics of the overburden, coal and underburden, demonstrate that <br />the Coalmont Formation is, in general, a poor aquifer. Although <br />varying artesian heads may be exhibited throughout the lease area <br />in varying formations, these pressures are in response to highly <br />localized conditions. It is not easy, in fact very doubtful, that <br />• a meaningful consistent piezometric surface is mappable over large <br />regions in the Coalmont Formation. <br />The observed permeability of the sediments previously mined <br />at the Canadian Strip Mine are examplementary of the generally poor <br />aquifer characteristics in the vicinity of the permit area. These <br />extremely low permeabilities were previously confirmed in both <br />direct analysis of core samples taken from an existing highwall in <br />the original pit, as well as from aquifer tests performed on ground <br />water monitoring wells for Pit 1. The direct permeability <br />measurements from cores are found in Table 14. Table 15 shows the <br />resultant transmisivities and permeabilities in the Pit 1 area <br />which were calculated from aquifer tests. <br />As can be seen by a comparison of the permeabilities in Table <br />14 and 15, the results obtained from aquifer tests in the wells <br />show permeabilities greater than those of the cores. This would <br />• indicate that actual groundwater movement is enchanted by a minimal <br />fracture or fault system *_hat promotes greater flow than the direct <br />-58- <br />~` -- - - -- °° - a- - - <br />