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~J 1 lJ 1 1 ll g.) Expansion of the temporary lower refuse pile began in early 1986. Additional placement of refuse, approval of the permanent Lower Refuse Area, and additional expansion of the refuse area took place from early 1986 until Sept. of 1986. Table 2.1-1 shows baseline and subsequent sampling of monitoring well GP-1 in the Lacer Refuse Area. Based on these sample results the refuse area does not appear to behaving any significant impact on the groundwater in the area. Due to the low permeability of the colluvial soil and the fact that no groundwater exists in the colluvium beneath the refuse pile, except along the margin of Sylvester Creek, it is not anticipated that any significant future impacts to the groundwater regime will occur. Figure 2.4-1 has been provided to show the correlation between flows in Sylvester Creek and well water elevations in well GP-1. This figure clearly shows the close relationship of well water levels to Spring runoff in Sylvester Creek. Rainfall does not have a large effect on the well level since the runoff is much more rapid than snowmelt and does not infiltrate as much. 2.2 Assessment of Springs Five springs in the North Half of the Dry Fork Basin are monitored monthly for flow. Also, within the mine permit area and adjacent area ten springs are monitored quarterly for flay. A comparison of current monitoring data with pre-mining data shows no significant trends which can be associated with mining activity. Most springs are responsive to spring runoff, but flan rates are sporadic and many times do not correlate well with other seasonal parameters such as snowpack, streamflow, etc. Appendix D contains bar graphs of spring monitoring activity for past years as well as the current year. 2.3 Assessment of Surface Water and AVF's Efforts were made in previous annual reports to characterize baseline river water quality to evaluate potential changes in surface water quality due to mining activities at the Mt. Gunnison No. 1 Mine. Continuous monitoring of stream floras and periodic monitoring of spring discharge rates are performed to provide the long term data base from which possible impacts of mining can be assessed. 2.3.1 Baseline Characterization of Water Quality and Streamflow A baseline characterization of North Fork water quality was performed in previous annual reports to evaluate the potential changes in North Fork water quality that could result from discharges at the Mt. Gunnison No. 1 Mine. Baseline characterization was performed downstream of the mine using data from the USGS stream gaging station on the North Fork near Somerset and from the West Elk Coal Co. water quality monitoring station on the North Fork belay the mine for sample data prior to the start of cronstruction in August , 1981. Both stations were downstream of the surface facilities area and downstream of all discharge points. Baseline data and analysis of these data are provided in the Mining and Reclamation Plan for the Mt. Gunnison No. 1 Mine and in the First Annual Hydrology Report. (13)