2012-12-20_GENERAL DOCUMENTS - C1981038

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Degradation of ground water quality could occur in three locations. The train loadout and auxiliary coal stockpile are located on an alluvial terrace of the North Fork of the Gunnison. Runoff infiltration could result in the dissolution of salts. The operator installed and monitors three wells downgradient from these facilities and has not detected any significant water quality changes. The Division has expressed some concern about the narrow band of alluvium found downdip of the underground waste development stockpile. The operator has installed a well (Node 22) and is monitoring that location for impacts. No impacts have been detected to date. Lastly, there is a slim probability that subsidence related impacts to springs might result in the modification of the springs' water quality due to a change in routing of the water. The operator is monitoring springs in currently affected areas quarterly for major cations and anions, and no changes have been detected. When mining was in progress, water utilized for mine operations was obtained from a well in the Steven's Gulch well field. Consumption from this alluvial/ colluvial deposit was measured with a wellhead gage. From July 1990 through June 1991, BRL produced 720,000 tons of coal and imported approximately 18,000 gpd from the Steven's Gulch well. Water quality information is also collected and reported to the Division. In 1986, CWI produced 333,292 tons of coal and consumed 8,700 gpd while in operation. In 1983, the Bowie No. 1 Mine produced 1.3 million tons of coal and consumed 27,400 gpd. There has not been any detectable impact to the groundwater /surface water regime in this well field since they initiated pumping at the site. Dewatering will occur at the Bowie No. 1 Mine but will be insignificant in extent. Mine inflows may be derived from fractures associated with perched aquifers within the overlying Mesaverde, surficial alluvial /colluvial sediments, and stream flows associated with fracture systems as well as from dewatering of the coal aquifer itself In 1983, approximately 300,000 gallons of water flowed into the mine from perched, discontinuous, water bearing sandstones overlying the D seam. A Division inspection in March 1986 documented inflows of 200 gallons per day. This inflow gradually slowed once this perched aquifer was completely dewatered. Inflows during 1991 failed to produce over 3 gpm for any significant period of time. Because the portals at the Bowie No. 1 Mine were sealed in 2001 and the Bowie No. 1 West Mine portals were sealed in 2000, there is no current information on mine inflows. BRL has established an extensive monitoring system to monitor water levels in colluvial /alluvial deposits in the permit area and in the alluvium of streams overlying mine entries. Permeability tests on colluvium in the East Roatcap Creek drainage averaged 7.2x102ft /day. No significant water level fluctuations have been noted in conjunction with mine inflows. Mine inflows in the mains underlying East Roatcap Creek averaged less than 1 gpm from 1987 to 1993. The permeability of the coal aquifer was measured in 1986 at 1.4x102ft /day. This insignificant aquifer has yet to make a visible contribution to mine inflows. BRL imported water for dust suppression from their wells in Steven's Gulch. In 1983, for example, the operator estimated that approximately 6.24 million gallons of water is consumed as moisture on the coal, 0.5 million gallons is consumed through increased humidity in the ventilation air, and less than 0.5 million gallons is lost through seepage into the floor of the mine. C'iirfarP Water The Bowie No. 1 Mine area will not significantly affect the local surface water hydrology or the regional hydrology. Sediment control measures will ensure protection to stream quality. No mine water will discharge from the portals and no water will be withdrawn from the creek. An Page 24 of 42