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Affected Environment and Environmental Consequences Changes in groundwater discharge quantity and quality. Cumulative water resources impacts were assessed by water balance and mass loading calculations for the mine through measured discharge points. 3.3.3 Affected Environment 3.3.3.1 Surface Water The Dry Fork LBA tract area encompasses portions of Deep Creek, Upper Dry Fork of Minnesota Creek, portions of the South Fork of Minnesota Creek, and the Lower Dry Fork of Minnesota Creek watersheds. All of the watersheds are tributaries to the North Fork of the Gunnison River (Figure 3-5). Based on the RFMP described in Section 1.8.1, it is assumed that the perennial stream Deep Creek and the perennial flow supplied to the Upper Dry Fork by the Deep Creek Ditch could be affected by mining subsidence in the Dry Fork LBA. The LBA tract includes a portion of the Deep Creek drainage, which flows north for about 5,000 feet across the Dry Fork LBA tract. The RFMP for the Dry Fork tract assumes the coal in [he E Seam would be extracted from longwall panels [rending northwest- southeast. Under [he RFMP, the longwall panels would be oriented roughly perpendicular to the Deep Creek drainage and parallel with the Dry Fork drainage. Deep Creek originates in a landslide feature on the northwest flank of Mount Gunnison immediately south of southern tract boundary. Deep Creek flows into Raven Gulch, which in tum flows to the North Fork of the Gunnison River. Deep Creek is ahigh-energy fluvial system that has carved a deep, incised channel between high mesas and is prone to flash floods that can carry voluminous debris from the exposed landslide materials in the headwaters. Deep Creek is a Rosgen-type G stream (Rosgen 1996) in the LBA area, with its channel incised in fluvial and colluvial deposits. The channel substrate consists of cobbles and boulders in a sandy matrix. The depth of this material below the streambed was estimated to be 15 to 20 feet based on the shot-hole logs from a shallow seismic survey on Deep Creek (Trace Ventures Explorations 1999). The average slope of Deep Creek through the Dry Fork LBA tract is 7.8 percent. Three unnamed ephemeral drainages enter the Upper Deep Creek drainage in the south half of Section 36, T13S, R90W (see Figure 3-1). Three Chapter 3 additional drainages enter Deep Creek in the south half of the LBA in Section 2 of T14S, R90W. MCC monitors Upper Deep Creek at a flume equipped with a continuous data logger located at the north edge of the Dry Fork LBA tract in the N 'h of Section 35. Monthly average stream discharge data collected at this flume ranged from 0.02 to 0.23 cubic feet per second (cfs) in 2003 (HydroGeo 2003). Water samples from the Upper Deep Creek flume indicate good water quality with low total dissolved solids (TDS) (HydroGeo 2003). The portion of the Dry Fork of Minnesota Creek within the LBA tract is an intermittent drainage that flows during high runoff events and during irrigation season (July to September), due to the contribution of approximately 12 to 14 cfs from the Deep Creek Ditch. Three tributary ephemeral drainages enter the Upper Deep Creek drainage in Section 2 of T14S, R90W. The southwest comer of the LBA tract in Section 11 of T14S, R90W also includes a portion of Lick Creek, a tributary ephemeral stream of the South Fork of Minnesota Creek. Mapping done by MCC found seven springs within the Dry Fork tract in sections 2 and 35 (See Figure 3-6). Springs in the general area are mostly seasonal, and issue from local water tables of limited lateral extent. Most springs are associated with colluvial deposits, and some issue from bedrock strata or fractures. Data from the ongoing hydrologic monitoring program show that spring flows in the area vary seasonally, and flow changes with variations in precipitation (HydmGeo 2004). The Deep Creek Ditch, operated by Minnesota Canal and Reservoir Company, traverses approximately 9,000 feet of the Dry Fork LBA tract along its south and southeastern boundary. The ditch delivers between 12 and 14 cfs to its discharge point in Minnesota Creek during the irrigation season (MCRC 2004). The ditch crosses Deep Creek in a closed flume (pipeline) supported by a steel trestle. Effects on the ditch and flume are addressed in Section 3.6 Land Use and Recreation. The existing West Elk Mine hydrologic monitoring program proximate to the Dry Fork LBA includes continuous flow monitoring on Upper Dry Fork, Lick Creek, and Upper Deep Creek, and Upper 3-16 Dry Fork Lease-By-Application FENS