2012-02-28_PERMIT FILE - C2009087A (3)

Home Browse Search

• Cow Camp Baseline Hydrology Work Plan Twenty Mile Coal Company — Revised June 5, 2008 Monitoring Well Installations Bedrock monitoring wells are proposed for three exploration hole locations planned for the Cow Camp Project, including ccu013, ccu014, ccu025. Wells will be completed in the Wadge underburden (WUB) at each location. An additional Wadge Coal (WC) and Wadge overburden (WOV) well will be completed at the location of exploration hole ccu025. Total estimated depths of each well are as follows: Exploration hole WC WOV ccu013 1140 N/A N/A ccu014 1150 N/A N/A ccu025 1840 1760 1750 * (depths estimated from ccu013) The exploration hole will be completed as a WUB well 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 at ccu025 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 the WC and WOV monitoring wells at exploration hole ccu025 will occur at short distances away following completion of the WUB monitoring well The geophysical log collected at ccu025 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: Existing 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 wells remain viable for collecting baseline