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I~ L • ~J West Elk Mine 2002 Annual Hydrology Report However, it is possible that the water level has also been impacted by mining of Panel 13 that was completed in years 2000 and 2001. Well SOM 129-H showed a sharp rise in water level early in WY2002 of about 50 feet. Water levels have remained steady since October 2001. The cause of the water level change is not understood and MCC will watch this situation carefully. Well 01-11-1, completed in the B-Seam, showed a rise in water level from November 2001 to April 2002 and has steadily dropped about 10 feet through September 2002. This may be due to mining of the Panels 14, 15 and 16 and dewatering of the B-Seam. These panels are located up gradient of the Well 01-11-1. The water level changes may also be a function of connectivity between the well and the North Fork. Flows in the North Fork were very low in the fall of 2002. No other wells showed changes during WY2002. 6.0 ADEQUACY OF THE MONITORING PROGRAM In the past 3 years the West Elk monitoring program was modified as a result of Technical Revision No. 88 (approved in August 1999) and Minor Revision No. 208 (approved January 1998). The monitoring program in WY2002 remained the same as WY2001. In WY2002 the West Elk Mine monitoring system was operating as designed and provided adequate data to assess potential mine induced impacts to the area's hydrologic system, with the exception of data collected at three stream stations and five wells. Upper Deep Creek, Lower Deep Creek, and Upper Dry Fork surface water stations are not functioning properly due to changing stream characteristics and casings wells SOM-45-H1, SOM-2-H, SOM-16-H, 96-27-1, and SO.W-1 have collapsed during the past several years, likely the result of mining induced subsidence. Pressure transducers and dataloggers were installed in the open stream channels at the Deep Creek stations. Control channel sections were established at each site. Flumes were not installed at these locations to limit impacts based on U.S. Forest Service (USFS) conditions. The Deep Creek stream channel is very dynamic and has changed considerably since the sites were established. As a result of erosion and sediment deposition the control channels used to calibrate the pressure transducers and gauge the stream flows are constantly changing and the flow data collected for Deep Creek in WY2001 and WY2002 is not considered accurate. The data and graphs presented in this report were developed using a rating curve developed from channel geometries measured in May 2002, but the raw data remains suspect. The Upper Dry Fork stream station was submerged by a beaver pond in WY2002 and the limited flow data that was collected is not considered accurate. Project # 00301 27 HydroGeo, Inc.