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• The total volume of water that could be evapotranspired from the vegetation study is assumed to <br />be under ideal conditions. In reality the evapotranspiration rates are slightly less. In many areas <br />shallow soils and rock ledges restrict rooting depths and inhibit maximum plant growth, thereby <br />reducing ET rates. <br />Aquifer Characteristics of the New Horizon Mining Areas <br />Eleven aquifertests were conducted within the New Horizon 1 leasehold, the proposed New Horizon <br />2 mining area and the immediate vicinity. Awide variety ofaquifertesting and analysis techniques <br />were employed because of the range ofwell yields and aquifertypes. Aquifertesting techniques <br />include constantdischarge tests (Theis, 1935; Neuman, 1975; and Cooperand Jacob, 1946); slug <br />injection and withdrawal tests (Cooperet a1., 1967, and Papadopulos et a1., 1973); modifed slug <br />tests (McWhorter, 1982); and specific capacity tests. Analysis techniques primarily involve <br />matching the drawdown of recovery data plots against theoretical type curves or tangent lines <br />defining the slope ofthe data. With the modified slug tests, data analyses included eithertype curve <br />matching or analytical solutions. <br />TransmissivityandhydraulicconductivityvaluesthroughoutandimmediatelyadjacenttotheNew <br />Horizon Mine are low to very low. The overburden and underburden aquifers have the highest <br />values and the coal aquifer has the lowest transmissive properties. There is an approximately one <br />order of magnitude range in the transmissivity and hydraulic conductivity values for the overburden, <br />coalandunderburdenaquifers. This suggeststhatthereisahighdegreeofspatialvariabilitywithin <br />the aquifers. Storage coefficient for the various aquifers vary by four orders of magnitude. The <br />alluvial aquifer has the largest storage coefficient (10-Z) and the coal and underburden aquifers <br />average about 10'5. The spoils monitoring well (GW-N27) was completed in the fall of 1987. A short <br />term specific capacity and transmissivity test was conducted at the time ofwater quality sampling <br />at Well CW-N27. A K value of 40 ft/day was determined. This was the highest specific capacity <br />and hydraulic conductivity values for any of the aquifers measured in the spoils aquifer. <br />In summary, aquifer yields atthe New Horizon Mine are very low. The better aquifers, in terms of <br />transmissivitiesavd hydraulic conductivities, are the overburden and the underburden. Yields were <br />so low that constant discharge tests were only attempted on one alluvial, one overburden and one <br />• (REVISED6/28101) 2.04.7-11 <br />