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below the water table. Therefore, drawdown impacts to these wells are expected <br />to be small. The wells are righted for irrigation water use. This area has been <br />mined and reclaimed for over 6 years ago and there has not been any problem <br />identified with these wells. <br />2. Impact of spoil material on groundwater flow and recharge. <br />The mine pit will remain open only until the coal has been removed. Following <br />the short-term water level decline on the groundwater system as a result of <br />pumpage of groundwater inflow to the pit, a potential long-term impact to the <br />local groundwater flow is the period of time necessary for resaturation of the spoil <br />material and reestablishment of a flow gradient. Another potential impact is <br />increased recharge into the spoil from precipitation and irrigation, resulting in <br />spoil springs developing downgradient. Fiuiire 2.05.6(31-1 in the nermit <br />application package shows a general cross-section downgradient through the New <br />Horizon #2 mine spoil. <br />Spoil material at the New Horizon 2 mine will be replaced into the mine pit areas <br />using 3 techniques: 1) cast blasting, end dumping of trucks from the spoil bench <br />and dozing. These techniques will increase permeabilities of the material in <br />comparison to the original overburden. Due to truck dumping from the spoil <br />bench, large rock will settle near the bottom of the pit and provide a permeable <br />channel for groundwater flow. The hydraulic conductivity (K) of the spoil, as <br />measured in well GW-N27, is 40 ft/day, which is far greater than any <br />measurement made in the overburden. K values in the overburden generally range <br />from 3.0 to 5.5 ft/day. The New Horizon #1 site has had continued seasonal <br />irrigation from the North Lateral and its secondary ditch which flows immediately <br />north of the New Horizon #1 reclaimed areas. Water from this irrigation and <br />some added precipitation have moved through the spoil and saturated it until it <br />discharges at the low point of the base of the coal which is at the Spoil Spring and <br />the Pond 001 discharge. Flow from this point fluctuates in response to the use of <br />irrigation. It is believed that the spoil in the New Horizon #2 Mine area will <br />remain relatively dry until irrigation is resumed from the West Lateral Ditch. <br />Once this irrigation is resumed, recharge will rapidly infiltrate into the spoil, <br />move to the southwest according to the basal gradient and develop a spring at the <br />low point of the lowwall crest, as was experienced at the New Horizon #1 Mine. <br />This point can be seen on Map 2.04.7-1A, near the northwest corner of the permit <br />area near Tuttle Draw. This point was calculated in CAD using the entire <br />excavated area for the mine compared to the surface topography. If any spring <br />develops here, it would discharge into Tuttle Draw. The Morgan property should <br />not experience any spoil springs. <br />Although a large diameter HDPE pipe will be used to carry the ditch water <br />through the permit area, infiltration will begin when the permanent HDPE pipe <br />will be used in re-establishing irrigation in the reclaimed area. This will occur in <br />2003 for the area east of 2700 Road and will occur after 2010 for the remainder of <br />32