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Ron Thompson Page 2 January 16, 1998 stream at either of these stations. However, field inspection indicated the evidence of a significant flow in September of 1997 due to storm events. Ground Water Quantity and QualitX The Division expressed concerns as a result of the 1996 AHR review that bedrock water level declines are greater than predicted in the probable hydrologic consequences section of the permit application. Drawdown estimates of bedrock water levels due to mining and subsidence were estimated in the permit to be one foot at up to 2.1 miles (I 1,088 feet). Review of the average depth- to-water readings for coal and overburden wells indicate drawdowns are substantially more than predicted (Table A). However, 1997 data indicates that the declining trend has reversed at NM-21 in the coal seam and water levels are rising. This is likely a result of flooding of the northern section of the workings as water moves down dip to the north and east. Declines in overburden well NM-20 continue, but at a slower rate than previously measured. Table A Well Zone Distance from mined area Depth to water 1994 Depth to water 1995 Depth to water 1996 Depth to water 1997 NM-20 Overbrdn 6000 ft 275 ft 320 ft 357 ft 363 ft NM-21 Coal 4000 ft 664 ft 796 ft N/A 762 ft NM-22 Overbrdn 10,000 ft 268 ft 374 ft 436 ft 440 ft SF-2 Overbrdn 3000 ft 518 ft 526 ft 653 ft 681 ft This is also true at NM-22, which returned a similar water level reading in 1997 as compared to 1996. This well is in the vicinity of two other wells, likely domestic wells for ranchette development. SF-2, completed in the overburden 3000 feet southeast of the mined area has shown over 350 feet of decline between 1994 and 1996. Rate of decline of the water level in the well has slowed in 1997, likely as a result of water levels beginning to recover in the flooded mine workings. One possible explanation for the decline in this well is the connection to the fault inflows encountered in the eastern development workings of the mine. Large fault inflows caused the abandonment of this area of the mine, and until flooding is complete, inflows may cause a continued drawdown of this well. The Division will continue to review semi-annual water level data to verify recover of these wells. Bedrock ground water quality sampling requirements were dropped from the monitoring program due to the distance from the mined area. Previous sampling had indicated an improvement in salinity due to gradient reversal caused by mining drawdown. As the mine workings flood, the natural groundwater gradient to the north-northeast will be re-established.