2008-02-04_PERMIT FILE - C1982056A

Home Browse Search

Water quality in Middle Creek above Mine 3 (U.S.G.S. Station 09243700) is of magnesium-calcium sulfate- • bicarbonate type. Total dissolved solids ranged from 434 mg/1 in April 1992 to 920 mg/1 in September 1992. Field pH ranged from 8.6 units in June 1992 to 8.9 units in September 1992. Concentrations of total recoverable iron ranged from 0.9 mg/1 in April 1992 to 9.7 mg/1 in September 1992. Total recoverable manganese concentrations ranged from 0.8 mg/] on September 16, 1992 to 7.9 mg/1 on September 23, 1992. Total recoverable zinc concentrations ranged from below detection limit in April 1992 to 0.2 mg/1 in September 1992. Other metals analyzed were consistently below detection limit. (31 Alternative Water Supply Information The application shall identify the extent to which the proposed surface coal mining operations may approximately result in contamination, diminution. or interruption of an underp~ound or surface source of water within th~rooosedpermit area and adjacent areas for domestic. agricultural. industrial, fish and wildlife, or other leeitimate use. If contamination, diminution, or interruption may result, then the description shall identify the alternative source of water supply or sources of augmentations water that could be develooed to reRlace the existing_sources. The alternate or substituted water shall be of a quality and quantity so as to meet the requirements for which the water has normally been used. (See Articles 83 and 92 of Title 37 of the 1973 Colorado Revised Statutes.) RESPONSE The adjudicated water rights in the Foidel Creek and Fish Creek water-sheds aze listed in Table 12, Summary of Surface Water Rights. Included in the table are points of diversion, ownership, nature of use, annual usage in cfs (flow rights) or acre-feet (storage rights). In general, adjudicated water is used for industrial, commercial and domestic purposes; or agricultural and domestic use. The most senior adjudicated flow and storage rights in the area • are owned by Twentymile Coal Company. Irrigation ditches are utilized in the Twentymile Pazk basin to facilitate farming of forage crops such as grass hay and alfalfa. The ditches are equipped with headgates for direct diversion from perennial streams, to be utilized in the late Bowing season (August and September) when otherwise dry conditions exist. The irrigation ditches are listed in Table 12, Summary of Surface Water Rights. Most of the ditches are abandoned; that is, they have not been used since 1975, according to the 1976 irrigation year survey records at the Colorado Division of Water Resources (CDWR) office in Steamboat Springs. Several of the ditches are currently listed in the 1984 CDWR Abandonment List. The extent of impact of underground mining operations on groundwater and surface water resources in the permit and adjacent areas is identified and analyzed in the Protection of the Hydrologic Balance section under Rule 2.05.6 (3). The impact of mining on the registered water rights listed in Table 12, Summary of Surface Water Rights, is based on that assessment. There are two aspects of the planned operations, which may affect sources of water for beneficial use; the first is partial dewatering of the overburden aquifer, and the second is handling and treatment of excess water, The overburden aquifer will be partially dewatered by inflow and subsequent pumping from the undergound operations. Inflow to the mine may cause drawdown of water levels in adjacent water supply and monitor wells. Quantitative estimates of inflow and drawdown are presented in the Protection of the Hydrologic Balance section under Rule 2.05.6 (3). Because of the confined non-tributary nature of the overburden aquifer discussed under Rule 2.04.7 (1) above, dewatering will not cause any noticeable depletion of private wells within the general area, as • documented under Section 2.05.6(3). PR03-06 2.04-38 05/07/03