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coal and underburden aquifers. This suggests that there is a high degree of spatial variability <br />within the aquifers. Storage coefficient for the various aquifers vary by four orders of magnitude. <br />The alluvial aquifer has the largest sforage coefficient (10-Z) and the coal and underburden aquifers <br />average about 10s. The spoils monitoring well (GW-N27) was completed in the fall of 1987. A <br />short term specific capacity and transmissivity test was conducted at the time of water quality <br />sampling at Well CW-N27. A K value of 40 ft/day was determined. This was the highest specific <br />rapacity and hydraulic conductivity values for any of the aquifers measured in the spoils aquifer. <br />In summary, aquifer yields at the New Horizon Mine are very low. The better aquifers, in terms of <br />transmissivitiesond 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 />underburden well. The aquifer characteristics show spatial variability suggesting anisotropic <br />properties within the medium and probable boundary effects. <br />Ground Water Quality <br />The following section discusses the results of chemical analyses for ground water samples <br />collected within and adjacent to the New Horizon mining areas. The monitor well locations are <br />presented on Map 2.04.7-1. <br />In the following water quality discussions, aquifers in the New Horizon 2 mining area are discussed. <br />Because of the significance of the irrigation water on the local ground water hydrology, an attempt <br />is made to separate irrigation period effects from non-irrigation period effects. Additionally, any <br />seasonal variability irrespective of irrigation periods is addressed. Data presented for trace <br />elements is limited to the period from 1985 to the present, because of the questionable nature of <br />the chemical data from earlier analyses. A further qualifier is that lead levels above the detection <br />limit, even after 1985 are ignored, because the only measurable values all occurred on the same <br />date in 1986 and measurable levels have not been detected since. Thus, the 1986 values are <br />considered lab errors. The special chemical parameters (Be, Co, Li and Vj required under ground <br />water agricultural standards from the Colorado Water Quality Control Commission were analyzed <br />in the New Horizon 2 mining area. <br />Revised 25 Jul 2002 2.04.7-12 <br />