2012-08-27_PERMIT FILE - C2009087A

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Cow Camp Project - Baseline Hydrology Work Plan Twentymile Coal Company — Revised July 23, 2012 Monitoring Well Installations Bedrock monitoring wells are proposed for three exploration hole locations planned for the Cow Camp Project, including ccu013, ccu014, and ccu023. Wells will be completed in the Wadge Underburden (WUB) at each location. An additional Wadge Coal (WC) and Wadge Overburden (WOV) will be completed at the location of the exploration hole CCU023. Total estimated depths of each well are as follows: Exploration hole WUB WC WOV ccu013 1140 N/A N/A ccu014* 1150 N/A N/A ccu023 1840 1760 1750 The exploration hole will be completed as WUB wells after coring and geophysical logging is completed. WUB wells will be drilled, screened and sealed to a depth of no more than 80 feet below the Wadge coal seam depending on the lithology encountered during exploration drilling. The WOV well ccu023 will be drilled to a depth of about 5 feet above the top of the Wadge coal seam, and will be screened for about 40 feet and sealed below the Lennox Coal Seam. Drilling and completion of WC and WOV monitoring wells at exploration hole ccu023 will occur at short distances away following completion of the WUB monitoring well. The geophysical log collected at ccu023 will be considered representative for all three monitoring wells completed at this location. Eight deep monitoring wells were completed in the Wadge Coal (WC and Wadge overburden (WOV) within the proposed Cow Camp mining area during the mid- 1980's. Total depths of each well are as follows: Existiniz Well ID Formation Total Depth (ft.bgs) 2637 WC 1019 2636 WOV 1008 2634 WOV 785 2635 WC 800 2633 WOV 803 2701 WC 974 2702 WOV 936 Well completion data from each well indicates the wells were completed properly in the formations monitored. Recent site visits conducted in May 2008 at the eight existing Cow Camp monitoring wells indicate the well remain viable for collecting baseline