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After the spoil aquifer has been fully rechazged, a mound of ground water will begin to develop in <br />the spoils. Eventually the spoil aquifer will begin to dischazge water to the bedrock aquifers, stream <br />alluvium, and ultimately to Stollsteimer Creek. <br />The rate of spoil water discharge will be a function of the recharge rate (infiltration and deep <br />percolation rates) of the reclaimed spoils. The estimated rechazge rate for the 13 acres of reclaimed <br />spoils over the East Pit spoil aquifer is 1 gallon per minute (gpm). Therefore, the rate of dischazge <br />from the spoil aquifer will be less than 1 gpm for the East Pit. A calculation of the discharge rate for <br />the spoils aquifer developed in the Barren Ridge Area has also been estimated to be less than 1 gpm. <br />Given a mean value for spoil water quality of approximately 5,000 mg/1 for TDS (data from other <br />surface mines in the state), a mean value for alluvial water quality of approximately 650 mg/1 for <br />TDS, an estimated flow rate within the alluvial aquifer of 55,555 gpm across the alluvial valley floor, <br />and a flow rate from the two spoils aquifer of 2 gpm, the total degradation which would result from <br />the two spoil aquifers will be 0.03 percent or an increase of 0.18 mg/1 TDS. These estimates aze <br />based on average or linear flow situations, whereas under actual field conditions, the increased TDS <br />levels would be concentrated in the area of the greatest amount of spoil material. However, it is <br />believed that the above-projected estimates are close to the potential actual field conditions and, with <br />the projected increases in TDS levels as low as those given here, the potential impacts would be <br />negligible. These projected TDS levels are similaz to those derived from a study done on the Barren <br />Ridge Area by Piteau Associates. This study concluded that both the water quality and water <br />quantity in Stollsteimer Creek would be impacted by less than one percent (Piteau Report, September <br />15, 1983, Exhibit 38, Federal Lease permit revision application). <br />The above information is sufficient to show that potential changes to water quantity or quality will be <br />negligible and, thus, there will be no material damage on site or off site to the water recharging the <br />AVF. <br />C. An environmental monitoring system was installed, maintained, and operated by the <br />permittee on the alluvial valley floors during surface coal mining and reclamation operations. The <br />Division approved suspension of the ground water monitoring until two years prior to the submittal <br />of a Phase III bond release application. The monitoring system will continue to be in effect until al] <br />bonds aze released in accordance with Rule. 3 (4.24.4). <br />XI. Operations on Prime Farmland <br />A. The Division has made a negative determination for the presence of prime farmlands within <br />the approved permit areas. The decision was based on the facts that there are no prime farmland <br />mapping units (see Exhibit 19, Volume N, of the approved permit application), and the land has not <br />been historically used as cropland. <br />Contact with Mr. Hancynn of the U.S. Soil Conservation Service in Pagosa Springs by Mariah <br />Associates, Inc. also verified that no prime farmland exists on the Revision No. 1 azea (page 5, Soils <br />Baseline Report by Maziah Associates, August 1983). The existing operations are in compliance <br />with (4.25.2). <br />18 <br />