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The spring which is adjacent to the permit area ~.~i.11 not lac affected during and after <br />mining, since the area of the L~7~land Terrace Deposit, which ~,~ill be mined through <br />is down-gradient of this spring. <br />The quantity of water recharging the Sudduth coal seam is expected to decrease and <br />the ground water quality within this seam is expected to be degraded following mining. <br />Infiltration studies within reclaimed areas o£ Pit 1 have shor,m that the infiltration <br />rate will be decreased. This decreased infiltration will reduce the recharge to <br />the spoil aquifer and the strata affected by mining. The ground water quality within <br />the .spoil aquifer and disturbed strata will become degraded through the leaching of <br />soluble salts from broken-up overburden materials. There will be an increase in total <br />dissolved solids (TDS) and a shift from a sodium bicarbonate to a sodium sulfate <br />type of water. The decreased recharge of the reclaimed area will not affect water <br />use on- or off-site since no wells are completed in, and no springs eminate from, these <br />affected strata in the permit and adjacent areas. The degraded spoil water quality <br />will not affect water use or affect surface water quality i=~ithin the permit and <br />adjacent areas. The only regional aquifers which will be affected by degraded spoil <br />water are the Sudduth coal seam and the Upper Sanrly Member of the Pierre Shale. <br />Both of these aquifers have low permeabilities and the migration of ground water <br />high in TOS from the spoil aquifer will be extremely slow. Movement of ground water <br />within these aquifers will be do~,m the dip of the strata to the axis of the Johnny <br />Moore Syncline. Due to the Iower infiltration rate, very low precipitation rate <br />(i.e., I1 inches per year), the increased storage capacity of the spoil aquifer, and <br />the presence of no springs or seeps from coal or sandy Mender in the permit and <br />adjacent areas; the degradation of surface waters from spoil water seeps or springs <br />is not anticipated. <br />VII. Assessment of Probable Cumulative Impacts (2.05.6(3)) <br />As required by Section 2.07.6(2)(c), this Division hasmade an assessment of the <br />probable cumulative effects of mining in tl~e vicinity of the Canadian Strip mine on <br />the hydrologic balance. This assessment includes a review of the Kerr Coal Company <br />Marr Strip mine, the Wyoming Fuel Company Canadian Strip mine, and the Bourg Strip <br />mine, owned by Walden Coal Company, which lies approximately five miles north of <br />the Canadian Strip mine operations. All three mines lie within the Canadian River <br />watershed. Zt is not anticipated that any measurable effects on either the quality <br />or quantity of Canadian River water will occur due to mining operations in the region. <br />Justification for this conclusion is as follows: <br />1. The Canadian River receives the majority of its water from snowmelt in the <br />hfedi cine Bow Range to the east of an area unaffected by any of the mining activities. <br />2. The precipitation in the region averages only eleven inches, most of which <br />occurs as snow. Therefore, runoff is principally from snowmelt, is slight, and <br />must flow for some distance through ephemeral channels allowing for waters to he <br />diluted and lost to alluvium recharge. <br />3. All waters leaving the sites are treated in sediment ponds and the majority <br />of these waters are used at the sites for dust control. <br />Effects: Surface Waters <br />The effects discussed here are related only to Bolton Draw, as this is the receiving <br />stream for waters leaving the Canadian Strip mine s.itc. <br />