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Degradation of ground water quality could occur in three locations. The train loadout and <br />auxiliary coal stockpile are located on an alluvial terrace ofthe NorthFork ofthe Gunnison. <br />Runoff infiltration could result in the dissolution of salts. The operator installed and <br />monitors three wells downgradient from these facilities andhas not detected any significant <br />water quality changes. The Division has expressed some concern about the narrowband <br />of alluvium found downdip of the underground waste development stockpile. The operator <br />has installed a well (Node 22) and is monitoring that location for impacts. No impactshave <br />been detected to date. Lastly, there is a slim probability that subsidence related impacts to <br />springs might result in the modification of the springs' water quality due to a change in <br />routing of the water. The operator is monitoring springs in currently affected areas <br />quarterly for major cations and anions, and no changes have been detected. <br />When mining was in progress, water utilized for mine operations was obtained from a well <br />in the Steven's Gulch well field. Consumption from this alluvial/colluvial deposit was <br />measured with a wellhead gage. From July 1990 through June 1991, BRL produced <br />720,000 tons of coal and imported approximately 18,000gpdfrom the Steven's Gulch wull. <br />Water quality information is also collected and reported to the Division. In 1986, CWI <br />produced 333,292 tons of coal and consumed 8,700 gpdwhile in operation. In 1983, the <br />Bowie No. 1 Mine produced 1.3 million tons of coal and consumed 27,400 gpd. There has <br />not been any detectable impact to the groundwater/surface water regime in this well field <br />since they initiated pumping at the site. <br />Dewatering will occur at the Bowie No. 1 Mine but will be insignificant in extent. Mine <br />inflows may be derived from fractures associated with perched aquifers within the <br />overlying Mesaverde, surficial alluvial/colluvial sediments, and stream flows associated <br />with fracture systems as well as from dewatering of the coal aquifer itself. In 1983, <br />approximately 300,000 gallonsofwater flowed into the mine from perched, discontinuous, <br />water bearing sandstones overlying the D seam. A Division inspection in March 1986 <br />documented inflows of 200 gallons per day. This inflow gradually slowed once this <br />perched aquifer was completely dewatered. Inflows during 1991 failed to produce over <br />3 gpm for any significant period of time. Because the portals at the Bowie No. 1 Mine <br />were sealed in 2001 and the Bowie No. 1 West Mine portals were sealed in 2000, there is <br />no current information on mine inflows. <br />BRL has established an extensive monitoring system to monitor water levels in <br />colluvial/alluvial deposits in the permit area and in the alluvium of streams overlying mine <br />entries. Permeability tests on colluvium in the East Roatcap Creek drainage averaged <br />7.2x l 02ft/day. No significant water level fluctuations have been noted in conjunction with <br />mine inflows. Mine inflows in the mains underlying East Roatcap Creek averaged less <br />than 1 gpm from 1987 to 1993. <br />The permeability of the coal aquifer was measured in 1986 at 1.4x102ft/day. This <br />insignificant aquifer has yet to make a visible contribution to mine inflows. BRL imported <br />water for dust suppression from their wells in Steven's Gulch. In 1983, for example, the <br />operator estimated that approximately 6.24 million gallons of water is consumed as <br />moisture on the coal, 0.5 million gallons is consumed through increased humidity in the <br />25 <br />