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• • L J 2.0 Hydrologic Dara lnrrrpremrion and lmpac! Assessment for the Permit and Adjacent .4rcat spring runoff conditions, as well as some precipitation events, the quality of water in the North Fork of the Gunnison is much worse than the quality of discharges from MCC sediment ponds. The river is also well outside NPDES effluent limitations. During winter baseflow and summer conditions water quality in the North Fork is better and is usually within NPDES effluent limita- tions. However, this is the time of year when MCC's ponds are rarely discharged. MCC completed construction of MB-2R and MB-3 in early 1994. Both ponds were lined with ageotextile/clay liner. MB-1 was cleaned and ageotextile/clay liner was also installed later in 1994. Mine water discharge was directed to MB-1 or to MB-2R. Construction of the material storage bench was started at the facilities during the latter part of the year. MCC also initiated construction of auxiliary facilities in Lone Pine Gulch. MB-4 did not discharge during WY 1994 and records indicate it has not discharged since it was constructed. MB-4 sometimes catches hydraulic oil washdown from the Unit Train Loadout. When this occurs, sorbent materials are placed in the pond to capture the oil product or the pond is pumped by a licensed contract hauler or the MCC vacuum truck. The pumped oil and water is deposited in the shop oil/water separator, the "clean" water is then discharged to MB-2R and the oil is collected in the used oil tank. There were several spills resulting in the removal of approximately 4,800 gallons of oily water. Mountain Coal initiated an Incidence Reporting process in October 1994, which should result in more detailed future reporting. Flow volumes from MCC sediment ponds are low relative to the North Fork of the Gunnison flows. Even during low flow R1.210IIOA/OS/OS/95(8:04am) 25 conditions on the North Fork MCC dis- charges represent an imperceptible differ- ence in stream quality. Based on the analyses, sediment pond dis- charges have had no adverse impact on the North Fork of the Gunnison River. The quality of discharges usually is better than the quality of the North Fork. In addition, pond discharge flows are so small that incremental changes in concentrations in the North Fork are imperceptible. Discharges of surface runoff in 1994 are expected to be similar in 1995. 2.6 ADEQUACY OF MONITORING PROGRAM An evaluation of the adequacy of the current monitoring plan was conducted to determine whether the program is covering anticipated affects. The mine workings map (Figure 2) was overiaid on the resources maps to deter- mine the potential resources which may be affected. Although several resources are above the mined area and adjacent to the mined area, overburden depths are great enough so that no impacts are anticipated. In addition, the un-named stock ponds are typically small dugouts to capture spring runoff and precipitation. Because there is no regular source of water, they are usually dry. Spring G-4 was awide-spread, seepy area. No measureable flows existed, just wet soil. Springs G-7 and G-8 were indistinguishable seeps located in a steep, rocky draw. Flows from the seeps were usually measurable in the Spring, only in one spot where they could be accumulated before flowing into a U.S. Forest Service stock pond. Other times of the year the springs diminished to just wet soils. The F- seam was developed at this location (1st East Submains), but no pillars were recovered, as the panel was abandoned and