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0 5.0 Ground Water Information <br />The data collected from Oxbow's groundwater monitoring sites, along with the results of <br />laboratory analyses are presented in Exhibit 2 - Groundwater Information. <br />The following site discussions are presented from west to east through the OMLLC property. <br />H-10 Well - B-Seam - Somerset Mine Workings - Hubbard Creek Drainage <br />The sealing of all of the abandoned Somerset Mine portals has precluded access into the mine to <br />obtain underground mine water samples from those abandoned workings. Instead, since the <br />Somerset mine was closed in 1985, monitoring wells H-10 and B-6 have historically been <br />utilized to monitor potential groundwater inflow and quality in order to predict the extent of <br />flooding in the abandoned underground workings. Monitoring water levels in these two wells <br />serves as a valuable predictive tool as to whether water from flooded mine workings could <br />impact the hydrologic balance. <br />The H-10 well is located in Hubbard canyon near the western limit of underground B seam <br />mining of the Somerset mine and near the north or down-gradient limit of the old mine workings <br />in that specific area. The elevation of the B seam in the well is - 6018 feet. From 1987 to 1989, <br />the water level in H-10 held steady at about elevation 6028 feet, and then in 1992 rose to <br />® approximately 6068 feet in elevation. From 1989 until 1999, the water level ranged from 6067 <br />feet to 6069 feet in elevation. In October 1999 and 2000 through 2008 no water could be <br />measured in the well. In 2009 the water level elevation was found to have reestablished and <br />ranged from 60887 to 6090'. In 2010, no water could be measured in the well. <br />Starting in 2006, the H-10 well was to have been used to monitor any B seam water level <br />resulting from the transfer of water from the D seam workings to the B seam workings through <br />borehole D2B2 located in the vicinity of the Hubbard Fansite. As of the data year 2008, no water <br />level had been encountered in H-10. With the sealing of the western mining district and sealing <br />of the Hubbard shaft on October 12, 2008, the pumping of water to D2132 was halted. <br />The reestablishment of a water level in the well in 2009 likely indicates inflow into the <br />abandoned mine workings in this vicinity. A comparison of the 2009 water quality data versus <br />the earlier pre-1997 data indicates little change with the exception of increased dissolved and <br />total iron concentrations and increased dissolved solids concentration, primarily as calcium. A <br />lack of a water level in 2010 indicates the variable nature of the ground water in the vicinity. <br />B-6 Well - B Seam - Somerset Mine Workings - Bear Creek Drainage <br />The B-6 monitor well is no longer in service and the following discussion is presented for <br />historical reference. <br />The B-6 well is also located in a down-gradient location in the abandoned Somerset Mine <br />workings in the vicinity of Bear Creek canyon. The elevation of B seam in this vicinity is 5925 <br />feet. In monitoring the B-6 well, the historical fluctuation of water levels has been different than <br />experienced in well H-10. After initially rising to elevation 6035 feet, the water level fell to <br />elevation 6014 feet in 1990. Water levels then recovered, with an increase to elevation 6033 feet <br />11