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II.C.3.h Groundwater Monitoring Program The Deserado Mine groundwater monitoring program <br />originally consisted of monitoring water levels and quality in the bedrock and in the White River alluvium. <br />This program included hydrology monitoring from eleven (11) bedrock monitoring sites and hydrology <br />monitoring of six (6) White River alluvium sites. The location of sites presently being monitored is shown <br />on Map 137. Table II.0 -12 shows which zones are monitored at which site and where water samples are <br />collected and water levels measured. Since ground water monitoring began in 1981, several events have <br />occurred which have changed the monitoring program. Table II.0 -13 gives the current hydrologic <br />monitoring parameters. <br />In the fall of 1984, Kenney Reservoir behind the Taylor Draw Dam was filled and the resulting rising water <br />flooded and destroyed five of the six alluvial monitor holes. Only one alluvial monitor hole (Qal -5) is now <br />being monitored. Monitor hole 2 -17L was cemented in October of 1985 as the hole was bypassed by <br />mining. The hole was cemented to prevent rapid discharge of water from the hole into the mine workings. <br />This monitor hole was replaced by drilling and completing a new hole in 1986 in the general vicinity of the <br />other 2 -17 holes. <br />Monitor hole 2 -12U was located near the center of longwall panel No. 1. This hole showed a significant <br />drop in water levels that corresponded in time with the passage of the longwall and subsequent <br />subsidence. Subsidence caused cracks, etc. obviously disrupted the "upper sandstone facies" <br />piezometric levels locally. The water level somewhat recovered and appeared to have stabilized. <br />However, this data was questionable and 2 -12U was dropped from the monitoring program. Well 2 -17M <br />was replaced by Well 2 -17TWM due to the plugging of the holes, apparently, by sloughing of the wall of <br />the well. <br />The Colorado Mined Land Reclamation Division in October of 1984 relaxed the monitoring requirements <br />for those monitor holes located in Federal Coal leases C -8424 and C -8425 with the stipulation that <br />monitoring would again resume at these holes. The resumption of monitoring at holes located at sites <br />29-4, 30 -8, 31 -7, 32 -7, and 33 -8 began one year prior to any mining activity in the lease in which the holes <br />were located. Water samples from the middle coal facie zone were to be collected and analyzed prior to <br />entering these leases. BME resumed monitoring of these wells in 1996 and collected and analyzed water <br />samples as required. Well 31 -7 is an upgradient well and will not be mined out. This well will be sampled <br />one more time within one year prior to bond release. The remaining wells are located within the longwall <br />extraction area and will be sampled one more time prior to mining through them. This will provide valuable <br />information because these wells are located down gradient and in some cases will not be mined out for ten <br />years. Each of the remaining wells will be sampled within six months prior to being mined out. Wells 29-4 <br />and 33 -8 are scheduled to be mined out. Well 30 -8 ended up in a pillar at the end on a longwall panel. <br />Well 32 -7 was mined through. These wells have been or will be sampled once before they are mined out <br />for the alluvial well parameters listed on Table II.0 -13. Water levels of all bedrock monitor holes identified <br />above will be measured annually during the summer (June 15 - September 15). <br />Minor Revision #149 (01/2012) II.0 -7 3 <br />