2008-03-03_PERMIT FILE - C2006085 (2)

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Eight residE~ntial wells were identified in shallower stratigraphic intervals above the 1000-foot drawdown zone, as summarized in Appendix 5. As stated above, water level changes are not expected in these wells because they are not completed in the same stratigraphic interval as either the mine or the rubble zone, but because of the remote possibility of impacts to these wells due to fracturing of the formations above the rubble zone, we recommend that these eight wells are included in the well monitoring program. Cross sections A - A' and B - B' illustrate the geologic setting and the well completion interval information discussed above. The cross sections illustrate the separation between the nearby wells both horizontally and vertically from the mine area and from the Ocean Wave coal. The results of this evaluation of potential impact indicate that all the nearby wells are completed in shallower geologic units not hydraulically connected with the Ocean Wave coal seam. There appears to be one well potentially penetrating the coal. This well, permit number 222887, was constructed within the fast two months to a depth of approximately 600 feet, and a Northfield representative had the opportuinity to visit the well site during the construction process. The Northfield representative interviewed the well driller and learned that the well did not penetrate the coal based on the driller's observations and comments. However, we conservatively believe that the well may penetrate close to the coal based on structural mapping of the coal ;seam and the reported well depth. This well is located approximately 2500 feet from the proposed mine boundary and the projected water level change in this one well ranges from 0 to 15 feet based on information available on the hydrologic properties of the Vermejo sediments. GroundwatE~r Use Groundwater use within the basin encompassing the proposed permit area and acljacent areas is generally limited to small volume domestic and agricull:ural/stock watering applications. A review of well permits within the cleneral area indicate that wells are completed in alluvial deposits within the Chandler Creek drainage system or shallow wells in the Raton and Vermejo Formations. Existing wells located within one mile of the mine boundary are listed in Exhibit K. The State's records were reviewed by Bishop-Brogden hydrologists and identified v~~rious wells that likely produced alluvial ground water from the ChandlE~r Creek alluvial deposits. These wells and comments on each well acre provided below. 2.04-21 Revised 11/05/07