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At the Overland Conveyor Area, we inspected the location where structures were demolished <br />and removed in 2001. This area contains a "mapped wetland" and a silt fence has been installed <br />as a sediment control for a road that runs parallel to a portion of the small wetland area (see <br />Photograph No. 12). The Permanent Flood Control Dike, which was approved and constructed <br />in 1985 using large rip -rap, was also observed (see Photograph No. 13). The dike remains stable <br />and is functioning properly. Lastly, we observed the new road /bridge construction associated <br />with Coal Creek Crossing (see Photograph Figure 14). Impacts to Coal Creek were minimized <br />during construction of the bridge and no issues or concerns were identified at any of these site <br />locations. <br />Monitoring wells UTL -01, 02, 03 and 04 and Rollins -2 were viewed during the walk through. <br />The wellheads were intact and secure and no concerns were identified. Upon approval of this <br />final Phase III bond release application, SCC intends to permanently seal and reclaim these five <br />wells and one additional Rollins Sandstone monitoring well (Rollins -3) located just to the east of <br />Interstate 70. The locations of these wells are shown on Attachment 1 - Bond Release Area <br />Map. SCC submitted a groundwater quality and quantity impact analysis with the SL -07 bond <br />release application for the six wells they intend to permanently abandon. Along with this <br />analysis the Division also reviewed the permit document including Tab 19 Probable Hydrologic <br />Consequences of Mining at the Roadside North and South Portals (PHC) and previously <br />submitted Annual Hydrology Reports. Based on this review the Division finds that mining <br />operations at the Roadside North and South Portals has not adversely impacted the quantity or <br />quality of groundwater in the alluvium of the UTL area or in the underlying Rollins Sandstone. <br />The following information is presented in Volume 2, Tab 7 of the permit document and is <br />summarized here for the alluvial groundwater of the UTL area. The alluvial fill of the Colorado <br />River in the project area is considered an aquifer. It is recharged by the river and presumably <br />discharges water to permeable units where they subcrop beneath it. Coal mining operations did <br />not physically contact the alluvium, and consequently, the effect of mining on ground water in <br />the alluvium will be controlled by the hydrogeologic properties of the Mesaverde Group which <br />separate the mining area from the alluvium. Also, the summary on page 19 -9 of the PHC states <br />"The probable hydrologic effects of underground mining are associated with subsidence <br />damage." Since no underground mining was conducted under the Unit Train Loadout area, the <br />impact from subsidence is nonexistent. The UTL wells were installed around the Unit Train <br />Loadout to monitor water levels in the alluvial material. The monitoring of water levels for these <br />wells began in 1984 and was discontinued in 1987. Quarterly water level monitoring was <br />resumed on the four wells in 1994 along with annual quality monitoring for UTL 2 and UTL 4. <br />SCC presented graphical information for water levels and water quality data for key constituents <br />in the groundwater impact analysis. The graphical representation of water level elevations shows <br />stable conditions with a slight decrease in water levels in all four alluvial wells. The water <br />quality data for UTL 2 (up gradient) and UTL 4 (down gradient) show stable trends with no <br />significant anomalies or adverse water quality impacts identified. Data from both wells showed <br />a minor overall decrease in pH. Total dissolved solids (TDS) remained relatively constant with <br />data from UTL 2 showing a slightly increasing trend and data from UTL 4 showing a slight <br />decreasing trend. <br />Page 12 <br />