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MINING AND RECLAMATION PLAN January 1986 <br />MT. GUNNISON NO. 1 MINE Revised October, 1989 • <br />Wells completed in the F seam are SOM-C76, SOM-23-H-3, SOM-2H, and <br />SOM-16H. Because several wells are dry, it would be inappropriate <br />to create a piezometric map to estimate a direction for groundwater <br />movement for the F seam coal. <br />The two wells, WR-2 and WR-3, were completed in the colluvium above <br />and below the initial waste rock pile. Monthly water level <br />recordings were initiated in September 1981. Well WR-2 was <br />destroyed in June 1982 during construction of the parking lot and <br />shop warehouse. Anew well, WR-2, was completed in November, 1982 <br />at a location 49 feet upslope of the original well. The initial <br />waste rock pile was removed in 1985. Consequently, the wells, WR-1 <br />and WR-2, were abandoned. <br />Wells B-16 and B27-2 were also completed in the colluvium and <br />Mesaverde Formation below the F seam. These wells were destroyed <br />during construction of the Mt. Gunnison Mine. These wells plus <br />the WR wells demonstrate the dry conditions associated with the <br />colluvium and Mesaverde Formation beneath the mine's surface <br />facilities area. <br />Water levels for the monitoring wells completed subsequent to <br />initial permit approval are included in the quarterly monitoring <br />reports. Three wells, A-1 (AV-1), A-2 (AV-2) and A-3 (AV-3), were <br />completed in the alluvium of Dry Fork Minnesota Creek in August of • <br />1984 (see Appendix D-5). These wells were monitored for a period <br />of time after the installation, but are not part of the current <br />groundwater monitoring program. water levels and water quality <br />monitoring will be resumed one year prior to mining in the area of <br />the Dry Fork. Wells will be installed and monitored in Lick Creek <br />as well, one year prior to mining in the area of this drainage. <br />Seven monitoring wells, SOM-38-H3, SW-1, SW-2, SW-3, SW-4, SW-5, <br />and SW-6 were completed over the first panel (1W15) to be subsided <br />and are used for subsidence evaluation. See Appendix A-19. Also, <br />four monitoring wells were completed in the colluvium'to monitor <br />groundwater above and below the waste rock and gab pile. See <br />Appendix B-9. The current well water level program is included in <br />Table 2.8.2.Y. <br />Aouifer Characteristics <br />Preliminary pump tests were run in cased and uncased holes <br />(SOM-C76A, SOM-22-H-2, SOM-64, and SOM-55) in the Barren Member. <br />Pump tests were also run in the F seam in wells SOM-C76, SOM-C76A, <br />SOM-23-H-3, and SOM-C35 (Exhibit 2.8.1.C). Transmissivity values <br />were estimated from Lohman 1975, using this method: <br />2-480 • ~ <br />