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middle, and south forks. The headwaters of the Purgatoire River • originate at an altitude in excess of 9000 feet above mean sea level in an area that receives substantial snowfall. The mean average pr_ecip-itation is 16.9 inches with snowmelt contributing approximately 5.0 inches to the total. The major drainages which could be impacted by this mining operation are the Purgatoire River, the Ciruela Canyon drainage, the Santistevan Canyon drainage, the Apache Canyon drainage and the Wet Canyon drainage. The Purgatoire River is a perennial stream and has an alluvial valley floor associated with it. The remainder of the drainages are classified as intermittent or ephemeral streams. The Colorado MLRD has added stipulations to the permit revision approval to protect the Purgatoire Alluvial Valley Floor resource. Because incomplete data were available, stipulations were added to the permit revision approval to require a complete hydrologic evaluation of Wet Canyon prior to Colorado MLRD approval of retreat mining in that area. Little or no bedrock groundwater had been encountered during the exploration activities, and only small volumes of water were encountered when the coal bed was intersected by mine development. Early in 1988, a substantial artesian flow of water (200-500 gpm) was encountered in conjunction with a fracture zone in the Second Right entry area of the mine. Its source is undetermined, but may be the underlying Trinidad Sandstone aquifer. Sandstone, shale, and coal seam discontinuity do not readily provide for the movement of groundwater through the area to be mined; the subject strata is situated above the Maxwell coal seam. The Maxwell coal seam is located near the middle of the Raton Formation and acts as a laterally extensive aquifer, but has limited permeability and poor quality. The Quartenary age alluvial deposits along the Purgatoire River contain ground water. These alluvial deposits are a major ground water source in the region. Most of the domestic, livestock, and irrigation wells identified in the permit and adjacent areas are completed in the alluvium adjacent to the Purgatoire River. The quantity and the quality of the water in this aquifer is dependent on the quality and the quantity of water in the river and the domestic, agricultural, and industrial activities on, and adjacent to the alluvial body. The Ciruela Canyon is an ephemeral or intermittent tributary to the Purgatoire River that flows primarily in response to snowmelt or moderate to heavy rainfall. This tributary receives mine water discharge from a settling pond. Water that is collected underground is pumped immediately to the surface and is held in this pond. This pond discharges through a dewatering device into the Ciruela Canyon drainage. This discharge is monitored regularly in accordance with the applicant's NPDES permit. The Ciruela Canyon Drainage has been permanently diverted to make room for the expansion of the coal refuse pile. The Colorado MLRD has reviewed 7