2011-01-13_REVISION - C1981038 (8)

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Transfer of Wells - The transfer to the Bowie No. 2 Mine of four exploration wells and portions of their associated access roads, along with their reclamation liability, is being proposed in Permit Revision No. 4. The four exploration wells are BRL-1-03-01, BRL-1-08-1, BRL-1-08-04 and 2010-2. Discharge of Water into an Underground Mine - Discharge of water into underground workings will not occur. Stream Buffer Zones - No disturbance is anticipated within 100 feet of a stream with a biological community. Probable Hydrologic Consequences - Ground Water - The Bowie No. 1 Mine has the potential to affect ground waters in three ways - degradation of water quality, mine consumption of water, and dewatering of insignificant bedrock aquifers. Each of these cases will be discussed in detail in the following paragraphs. 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 28