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in well GW -N27, is 40 ft/day, which is far greater than any measurement made in the overburden. <br />K values in the overburden generally range from 3.0 to 5.5 ft/day. The New Horizon #1 site has had <br />continued seasonal irrigation from the North Lateral and its secondary ditch which flows <br />immediately north of the New Horizon #1 reclaimed areas. Water from this irrigation and some <br />added precipitation have moved through the spoil and saturated it until it discharges at the low point <br />of the base of the coal which is at the Spoil Spring and the Pond 001 discharge. Flow from this point <br />fluctuates in response to the use of irrigation. It is believed that the spoil in the New Horizon #2 <br />Mine area will remain relatively dry until irrigation is resumed from the West Lateral Ditch. Once this <br />irrigation is resumed, recharge will rapidly infiltrate into the spoil, move to the southwest according <br />to the basal gradient and develop a spring at the low point of the lowwall crest, as was experienced <br />at the New Horizon #1 Mine. This point can be seen on Map 2.04.7 -1 A, near the northwest corner <br />of the permit area near Tuttle Draw. This point was calculated in CAD using the entire excavated <br />area for the mine compared to the surface topography. If any spring develops here, it would <br />discharge into Tuttle Draw. The Morgan property should not experience any spoil springs. <br />Although a large diameter HDPE pipe will be used to carry the ditch water through the permit area, <br />infiltration will begin when the permanent HDPE pipe will be used in re- establishing irrigation in the <br />reclaimed area. This will occur in 2003 for the area east of 2700 Road and will occur after 2010 for <br />the remainder of the mine area west of 2700 Road. It is estimated that full irrigation of the <br />reclaimed area will take place by year 2013. Although the pipe will be used to carry the ditch flow <br />until the end of its useful life in 30 -50 years, its use is not relevant to the prediction of irrigation <br />recharge since this recharge will occur over 99% of the area even when the permanent pipe is in <br />place. <br />From soil information, knowledge of the irrigation practices, discussions with USGS, and the rainfall <br />date for the site, the following recharge data has been calculated: 2" from rain and snowmelt, 13" <br />from irrigation and 1" from underburden recharge and overburden recharge at the uphill <br />spoil /overburden contact. Total long -term recharge is therefore 16" per year. These predictions are <br />approximate but suffice in predicting the behavior of the groundwater in the spoil. <br />Revised September 2014 JR -64) 2.05.6(3) -23 <br />