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_. iii iiiiiiiiiiiii iii A 999 NEW PRYOR MINE EXISTING ENVIRONMENT DESCRIPTION The New Pryor Mine lies at the western edge of the Great Plains of Colorado in the Raton-Trinidad Coal Field south of Walsenburg. The area is predominately a semiarid, shortgrass ecosystem. The gently sloping portions of the permit area are characterized by a diversity of grasses, fortis, and low shrubs. The steeper slopes have a cover of pi non and juniper, interspersed with decidious shrubs. Land use is basically rangeland. Present rangeland conditions are poor to fair using Soil Conservation Service standards. This poor condition is due in part to the extensive past underground coal mining and the associated surface disturbances. Map 2 of this document shows the horizontal extent of past mining and the portals of other mines. Open shafts, waste piles, and subsidence features in the area have been mapped by the Inactive Mine Reclamation Program. There are no known cultural or historic resources listed on the National Register of Historic Places within the immediate area. This conclusion is based on a Colorado Historical Society letter which was included with the original mine permit application and is attached to this document. Geologically, the mine lies on the northern flank of the Raton Basin Coal Field. Outcropping formations in the general area are illustrated on Figure 1 of this document. The oldest exposed unit is the Trinidad Sandstone of Cretaceous age, a possible regional aquifer. This unit was followed by the shallow water, deltaic, and swamp deposits of the Vermejo Formation. Most of the past mining in the Walsenburg area has been concentrated in six of the eight lenticular coal beds of the upper Vermejo and lower Raton Formations. There are numerous, near vertical, Tertiary dikes exposed in the area. The dikes appear to have filled fractures in sediments as a result of tectonics related to the synclinal fold of the basin. Structural dips in the permit area are relatively gentle and range from 4o to 6o to the west-southwest towards the synclinal axis. Several faults striking north-south were interpreted to exist within the permit area as is shown on Figure 2 of this document. The Trinidad Sandstone, the only potential confined aquifer in the general area, outcrops within the permit area. The top of this formation outcrops in a discontinuous fashion between the confluence of Pryor Canyon and an unnamed drainage and Black Hawk Canyon. Being at such shallow depth and within 500 feet of the outcrop, the likelihood of a saturated aquifer is minimal. Streamflow generated recharge is the major water source for ground water in the aquifer. Part of a SOAP investigation included sampling of water stored in an old mine void in the Vermejo Formation directly north of the permit area. This water sample indicates the long term effects of exposing water to overburden materials in near proximity to the Cameron coal seam. The concentration of almost all of the parameters analyzed were well below the permissible limits. The only exceptions were iron and manganese which were slightly higher. The total dissolved solids were high and the water was generally hard.