2012-10-29_GENERAL DOCUMENTS - C1981012

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lies from 450 to 900 feet below the surface. Immediately above the coal are interbedded sandstones, siltstones, and shales. Interbedded sandstones, shales, and siltstones also underlie the seam. The alluvium of the Middle Fork of the Purgatoire River is a significant aquifer in the permit and adjacent areas. The Purgatoire River originates several miles west of the mine in the Sangre de Cristo Mountain Range. It flows into the Arkansas River near Las Animas, Colorado, approximately 120 miles northeast of the mine. Portions of the Apache Canyon, Pete Canyon, and Ciruela Canyon drainages are found within the permit area. These basins contain intermittent and ephemeral streams that flow predominately in response to runoff from snowmelt during the spring and intense rainfall during the summer. A portion of the flow in intermittent drainages is sustained by groundwater discharges. Pete Canyon is tributary to the North Fork of the Purgatoire River, while Apache and Ciruela Canyons are tributary to the main stem of the Purgatoire River. The region is characterized by a semi -arid climate. The prevailing wind is from the southwest and average annual precipitation is 16.92 inches. The length of the growing season in the area varies from 90 to 110 days. Vegetative communities in the area of the mine can be separated into two physiognomic types: the low grassland and riparian communities along the Purgatoire River valley bottom, and forest communities dominating the slopes and upland areas along the river valley. Communities on the north- facing slope and the river valley were inventoried and found to contain four distinct vegetative communities at the New Elk Mine area: a Ponderosa pine - Douglas fir -oak community, a Ponderosa pine -oak community, a grassland community, and a riparian willow carr community. The Ponderosa pine - Douglas fir -oak community is found on the north - facing slope above the mine facilities at elevations above 7,600 feet. The overstory consists of mature Ponderosa pine and Douglas fir with interspersed pinon pine and Rocky Mountain juniper. The dominant shrub species is Gambel's oak. Vegetative cover is relatively sparse (12 percent) and productivity is low (62 lb. /ac). The Ponderosa pine -oak community occurs on the north facing slopes above 7,500 feet on the eastern two- thirds of the permit area. Pure Ponderosa pine stands are interspersed with Gambel's oak, pinon pine, and Rocky Mountain juniper. Vegetative cover is low (4 percent), as is productivity (44 lb /ac). The grassland community was inventoried at the adjacent Golden Eagle Mine on a plateau above the river at 7,200 feet elevation, since no undisturbed grassland communities could be found at the New Elk Mine. Dominant grass species were blue grama and western wheatgrass, with many other minor graminoids including a number of forbs. Sage and snakeweed were the dominant shrubs. Vegetative cover can be characterized as moderate (18 percent), as is productivity (560 lb. /ac). The willow carr riparian community is located in the Purgatoire River drainage at an elevation of 7,400 feet at the New Elk Mine. The dominant species was willow with a diverse graminoid and forb understory. Vegetative cover is high (43 percent), as is productivity (2,140 lb. /ac). Soils in the area range from very shallow on the steep side slopes to deep, well- drained loams with a dark- colored surface layer found in the valley bottom along the Purgatoire River. The Jansen Loadout is located in an unincorporated area on the west side of Trinidad, Colorado. Land use of the site has been industrial for at least two decades. The site is located immediately north of and adjacent to the Burlington Northern Santa Fe (BNSF) railroad grade on a thin layer of Purgatoire River alluvial deposits capping bedrock sedimentary formations. No intermittent, ephemeral, or perennial 1.1