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SNOWCAP COAL COMPANY, INC. HYDROLOGIC ANALYSIS OF UNIT TRAIN LOADOUT AND ROLLINS SANDSTONE GROUND WATER WELLS The following analysis and attachments are based on Snowcap Coal Company's Mining and Reclamation Permit #C-1981-041 and monitoring data from Snowcap's Annual Hydrology Reports. This data represents eight (8) ground monitoring wells reported as UTL 1, 2, 3 and 4 and Rollins 1, 2, 3 and 4. Volume 2, Tab 7 of the permit includes Appendix 7-1 which is a study performed in 1977 by Willard Owens Associates, Inc. titled Hydrology of Roadside Mining Corporation Operations". Page G-16 of this report states "The alluvial fill of the Colorado River in the project area is also an aquifer. It is recharged by the river and presumably discharges water to permeable units where they subcrop beneath it. However, coal mining operations will not physically contact the alluvium. Consequently, the effect of mining on ground water in the alluvium will be controlled by the hydrogeologic properties of the Mesaverde Group which will separate the mining area from the alluvium." Also, the summary on page 19-9 states The probable hydrologic effects of underground mining are associated with subsidence damage." Since no underground mining was conducted under the Unit Train Loadout area, the impact from subsidence would be negligible to nonexistent. The UTL wells were installed around the Unit Train Loadout to monitor water levels in the alluvial material. The monitoring of water levels for these wells began in 1984 and was discontinued in 1987. Quarterly water level monitoring was resumed on the four wells in 1994 along with annual quality monitoring for UTL 2 and 4. The enclosed diagram 2 is the graphical representation of water level elevations in these wells along with the CFS of the Colorado River on that same day. This graph shows how the water levels of the wells correspond with the flow of the adjacent Colorado River. The data is from Aug/Sept readings which correspond more closely with the annual water quality analysis which were performed. Diagram 3 is the data table listing the water quality analysis of UTL 2 and 4 wells and diagrams 4 through 15 are graphical representations of this data. UTL 2 well is located upstream of the mining surface disturbance and UTL 4 well is located more downstream. Locations are shown on the "Bond Release Exhibit" enclosed with this packet. We submit that water levels and water quality of these wells, as shown on the enclosed diagrams, have not been adversely impacted due to activities associated to mining. Pages 19-5 and 19-5a specifically speaks to the impacts of mining on the Rollins Sandstone. It states, "The Graystone report in Appendix 7-3, Volume 2, evaluated the hydrologic characteristics of the Rollins Sandstone which lies 5-22' below the Cameo B- seam. Their conclusion was that "Since no beneficial quantities of water are present in the Rollins Sandstone and an aquitard separates the Rollins Sandstone from the Cameo B-seam, minimal effects on the quantity of water are expected." They went on to say that the impact of mining on the quality of water in the Rollins Sandstone should also be minimal." Rollins 1 (aka RSN Well) and Rollins 4 (alga RSS Well) were both sealed in 2000 when the underground portals were sealed. Enclosed are diagrams 16 through 29 showing the quantity and quality annually for the Rollins 2 and 3 wells. The quantity (depth) of the wells, are depicted on the graph on diagram 17, which shows that the water levels have not been adversely effected since monitoring began in 1997. We also submit that the quality of these wells, as depicted on diagrams 18 through 29, has not been adversely impacted due to activities associated to mining. SL-7 07/10