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A = 103,500 ft2 (Dakota Coal at Cross Section A) <br /> A = 36,000 ft2 (Dakota Coal at Cross Section A) <br /> A = 298,479 ft2 (Underburden) <br /> Q = 15,255 ft 3/day (Overburden through flow discharge at Cross Section A) <br /> Q = 46,816 ft 3/day (Overburden through flow discharge at Cross Section B) <br /> Q = 9,288 ft 3/day (Overburden through flow discharge at Cross Section C) <br /> Q = 492 ft 3/day (Dakota coal through flow discharge at Cross Section A) <br /> Q = 171 ft 3/day (Dakota coal through flow discharge at Cross Section B) <br /> Q = 4,133 ft 3/day (Underburden through flow discharge) <br /> Drainage from storage in the overburden aquifer also contributes to the baseflow of <br /> Calamity and Tuttle Draws. To determine discharge from storage the following drain <br /> equation was used as described by Lohman (1972): <br /> Qs = 2s ST <br /> 'fY t <br /> where: <br /> s = saturated thickness <br /> S = storage coefficient <br /> T = transmissivity <br /> t = time <br /> Q = 1 ,521 ft 3/day (Discharge from storage at overburden Cross Section A) <br /> Q = 3,796 ft 3/day (Discharge from storage at overburden Cross Section B) <br /> Q = 382 ft 3/day (Discharge from storage at overburden Cross Section C) <br /> By adding the overburden aquifer through flow quantity with the quantity of water released <br /> from storage (inflow) and comparing it with the respective stream baseflow (outflow) the <br /> values should be similar. <br /> Calculations of ground water flow (inflow) from the overburden, Dakota coal and <br /> underburden indicate that the aquifers are discharging 77,058 ft3/day, 663 ft3/day, and <br /> 4,133 ft3/day, respectively through the defined cross sections. Discharge from the Dakota <br /> coal and the underburden is relatively small compared to the overburden. As seen on <br /> 7-16 Revised 04/11/88 <br />