2008-03-31_PERMIT FILE - C1980007A (34)

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West Elk Mine • • Table 16 Location, Flow; and Overburden Thickness for Springs in the Permit Area Overburden Overburden Spring Basin Flow Range (gpm) Source Thickness Thickness Spring Fall (feet from B- (feet from E- Seam Mining) Seam Mining) J-10 D Fork 0.07-7.5 1.5-8.1 300 WCC-12 D Fork See * 590 WCC-14 D Fork See * 590 WCC-15 D Fork 0.48* 600 WCC-2 D Fork See * 690 WCC-1 D Fork See * 740 D-9 D Fork See * 780 D-8 D Fork 2.88* 480 J-5 D Fork 0.94-6.0 See 500 21 D Fork 3.75-7.5 1.25-11.5 620 J-2 Lick Creek See *-0.23 Seep-0.08 380 WCC-22 Lick Creek See * 420 R-5 Lick Creek See * 500 R-10 Lick Creek See * AC 650 WCC-3 Lick Creek 0.94 920 * = One Measurement Only C = Colluvium A = Alluvium M = Snow Melt interference B = Bedrock S = Fed by upgradient spring = Post-mining Data 2 = Resource has been undermined, but data are baseline. Since 1978, discharge rate data have been collected from 83 springs. Flow rates range from 0 gpm to 120 gpm. It is important that a majority of the springs have at least 300 feet of overburden above the highest seam to be mined. The significance of this is discussed in detail in the Probable Hydrologic Consequences discussion in Section 2.05.6. Four springs in the permit area exhibit significant flows: Spring G-26a (peak flow during spring runoff up to 75 gpm) in Lone Pine Gulch, G-24 (up to 120 gpm) in Sylvester Gulch, and G-25 (up to 90 gpm) and G-31 (up to 45 gpm) in Gribble Gulch. The springs with the largest past flow rates in the Apache Rocks pen-nit revision area are identified as D- 2, J-4, and J-10 with peak discharge rates ranging from 8.9 gpm to 30 gpm. The flow rates of all springs are highly seasonal. Most spring flows will peak during the late spring/early summer and will diminish throughout the sununer until only flowing at a trickle or drying up. The increased flows usually will not return until the following spring except for short duration flows in response to intense stonn events. An ideal example of the seasonal cycle is represented by Spring G-26a located in Lone Pine Gulch, (see Map 37) and shown in Figure 11. There are approximately 50 springs in the South of Divide permit area. Most of the springs are located along the 5 g valley floors of Dry Fork, Poison Gulch, and Lick Creek. There is only one spring (Spring 21 - Deer Creek Domestic Springs Pipeline) that has been decreed in the South of Divide area to the south of Minnesota Reservoir. The State Engineer's Office does not have diversion records for the structure. so it is not clear if the spring is still in use. There are three springs (WCC-24, J-7, and J-2) that had flow at all of the initial observations (Map 37). Of these springs only J-7 is within the influence of the projected longwall panels. Springy J-7 is located along Dry Fork with an overburden depth of 680 feet over longwall panel E2. Additional spring information is contained in Exhibit 71, updated for Dry Fork Lease. 2.04-104 Revised A'ovewber 2004 PRI G: Rev. Apri12006 PRIO: Sep. 2007 PR12; Feb. 2008 PR 12