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<br />Underlying the Vermejo Formation is the Trinidad Sandstone, which is an aquifer of significant <br />regional extent. However, numerous old mine workings have had a serious affect on groundwater in <br />the mine area. Therefore, almost no water contained in the aquifer is used. The mine is located in a <br />recharge area for the Trinidad Sandstone. <br />Samples of water from local wells were found to contain extremely high levels of sodium, sulfate, and <br />bicazbonate. Plumes of water of degraded quality originate in the old mine workings and spread <br />downdip in a west-southwest direction. <br />Within the permit azea are two ephemeral drainages. The Maitland and Gordon Arroyos flow only in <br />direct response to rainfall or snowmelt. Both arroyos drain from the west to the east. <br />The region is characterized by a semiarid climate. The prevailing wind is from the west. Average <br />annual precipitation is 15.3 inches. The average annual growing season is approximately 200 days. <br />Soils at the mine site are of the orders Aridisol and Entisol, which characteristically demonstrate little <br />to no profile development. These soils aze chazacteristic of semiarid environments. Soil depth and <br />degree of development vary with topographic position and microclimate effects. Generally, the deeper <br />and better developed soils occupy valley bottoms while shallow soils of lesser horizon development are <br />located on slopes and ridge tops. <br />Vegetation is distributed as a result of the soil, slope, and aspect characteristics of the site. A pinon- <br />juniper community is found on foothills and upland areas above 6,300 feet, primarily in the south and <br />west portions of the proposed permit azea. This community is composed primarily of shrubs and trees <br />with a sparse understory. Pinon pine and Utah juniper are the dominant species in this community. <br />Cover is low (6 percent), as is productivity (250 lbs./ac). <br />A grassland community is found on the flat and gently rolling portions of the permit azea at elevations <br />below 6,300 feet. This community is composed of a mixture of cool and warm season grasses, <br />dominated by Blue Grama and Three Awn. Cover and production, 26 percent and 918 lbs./ac <br />respectively, are moderate to low. There are also several small disturbed vegetation communities. <br />These species have invaded areas where surface disturbance (mainly from mining) resulted in the <br />native community being weakened or destroyed. <br />Description of the Operations and Reclamation Plan <br />With the approval of TR-09, operations became oriented toward reclamation only. Forty-nine (49) <br />acres of Colorado Coal Mine No. 1 were reclaimed in late 1989; the test bum pit and ancillary struc- <br />tures. Kaiser Steel Resources applied for Phase I Bond Release on the property on July 20, 1990, and <br />the Division proposed an affirmative decision on the release on November 19, 1990. <br />Kaiser Steel Resources submitted Technical Revision No. 12 on September 27, 1991 to remove the <br />sediment ponds at the site. Hydrologic modeling successfully demonstrated that vegetation cover had <br />stabilized erosion from the site to conditions better than or equal to pre-mining conditions. Kaiser <br />6 <br />