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standards and thereby meeting BLM's Land Health Standard 5. Surface water is typically alkaline and is a calcium- bicarbonate-sulfate chemical type. Suspended solids levels and total metals concentrations can increase in surface flows during snowmelt runoff and major thunderstorm events. Ground water quality can vary depending on its source. Perched ground water typically exhibits similar water quality to su,-face flows, while ground water within the water table system (:includes the coal seams) is commonly of poorer quality with moderate to high alkalinity, asodium- bicarbonate chemical type, and increased dissolved solids concentrations. Environmental Consequences & Mitigation: o d cti n: Because no surface disturbance, other than minor subsidence effects, is proposed or contemplated in conjunction with the proposed coal lease modification. it is not anticipated that surface drainage would be disturb?d or surface water quality impacted. Based on previous subsidence evaluations. surface subsidence effects would be negligible clue to overburden thicknesses averaging 2.500 feet in this area and arty minor surface subsidence effects would not affect surface drainages. The mine development and mining activities associated with [he proposed coal !ease modification •.vould result in some ground water drainage into the mine workings during and following active mining operations. however, ground water is not beneficially utiliz?d in this area so no water users would be impacted. Ground water chemistry and quality could be affected through contact with exposed coal and rack in the mine workings, however, available sampling information for mine water inflows and mine water discharge indicate that mine water quality meets all applicable state water quality standards. .4n Aquatic Impairment Study (Colorado School of Mines, 1994) was completed to evaluate the potential for mine water discharge from the ongoing Sanborn Creek mining operations to adversely impact aquatic resources in the North Fork of the Gunnison River. The results of this study confirmed that mine water discharge would have little or no impact on downstream aquatic resources and environments. No impact AJterttative 4 Because no additional surface or underground disturbance would occur under the No-Action Alternative, surface and ground water systems would not be disturbed or impacted. No impact. Signature of specialist: Dennis Murphy WILDERNESS, AREAS OF CRITICAL ENVIRONMENTAL CONCERN, WILD AND SCENIC RIVERS ffected Environment: The proposed lease modification area doe:; not include and is not in close proximity to any / designated Wilderness Area, Wilderness Study Area, Areas of Critical Environmental Concem, or Wild and Scenic ( Rivers. Environmental Consequences & Mitigation: Proposed Action: Given that no designated Wilderness. Areas of Special Environmental Concem, or Wild and Scenic Rivers exist within or near the subject area, there would be no impact. No impact. Alternative ~ Given that no designated Wilderness, Areas of Special Environmental Concem. or Wild and Scenic Rivers exist within or near the subject area, there would be no impact. No impact. Signature of speciaiist: Karen Tucker WILDLIFE, AQUATIC fA fected Environment: The only surface drainage or other sur.`ace water body in or in close proximity to the proposed lease modification area is Hawksnest Creek, a small ephemeral tributary to the North Fork of the Gunnison River. Due to steep channel gradients, brief, high-intensity seasonal flows, and the lack of a developed floodplain or riparian community characteristic of Hawksnest Creek, it does not support a viable aquatic community and does not meet the applicable criteria for aquatic environments and resource:; under Standard 3. The only other potential for