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Mountain Coai Company 1997 Annual Hydrology Reporl West Eik Mute monitoring and evaluation will continue in an effort to determine an explanation for the • decreasing water level. Monitoring well So.W-1 also shows a declining water level. Given its location upgradient of the B-Seam workings, it should not be impacted by mining, so there is likely another explanation. As the well is currently being monitored for baseline conditions, insufficient water level and water quality data aze available to assess the significance of these observations. WY96 marked the reinstatement of well SOM-23-H-1 into the monitoring program by reinitiating baseline monitoring. This baseline monitoring continued in WY97. Water level observations made during this year are similar to those for WY96 which show an increase of more than 550 feet from those observed in 1978. As discussed previously, the SOM-23 cluster of wells have been affected by a landslide in the immediate vicinity. Observations from WY97 indicate that there is cascading water entering the well. Therefore, the WY96 and WY97 observed water levels and water quality results are considered to be associated with anear- surface source. Because of [he observed cascading water and known landslide activity at the well cluster, SOM-23-H-1 will likely be removed from the monitoring program in a future revision application. WY97 water level observations for well SOM-129-H show a leveling off of the falling water levels first observed starting in WY95. The WY97 data indicate a stabilization of the water table approximately 95 feet above the total depth of the well. Water quality analyses conducted in WY97 show results within baseline conditions with the exception of TDS (2800 mg/L) which is • below the baseline range (3200-4000 mg/L). Rollins Sandstone Wells There are currently three monitoring wells which are completed in the Rollins Sandstone. These include: LP-1, So.W-3 and SOM-128-H. Reliable water level observations in well LP-] have not been recorded since 1995, afrer collecting one year of data. These water level measurements reported dry, moist or muddy conditions at a depth of approximately 135 feet, which is the total depth of LP-l. Field observations from WY96 indicated that the casing was blocked or bent between 75 and 85 feet below the ground surface. Observations from WY97 indicate the blockage may now be between 65 and 70 feet below the ground surface. It is believed that the lazge and continuously active historic landslides in the azea have damaged the well casing sufficiently to deter full depth measurements. As a result, MCC was unable to collect water samples in WY96 or WY97, and the well will likely be removed from the monitoring program in a future revision application. Water level data obtained in WY97 for monitoring well So.W-3 in the Dry Fork of Minnesota Creek continue to show dry conditions approximately 220 feet above the completed bottom of the well (i.e., is blocked or damaged) during its second year in the monitoring program. As a result, no water quality samples were obtained. MCC will further investigate the blockage or damage of the well. • 1-0 .a50 age rig r arer ngineers