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2005 Subsidence and Geologic Field Observations Box Canyon, West Flatiron, Apache Rocks, and South of Divide Mining Areas 4.13 Traverse L-L' Traverse L-L' begins at the fork in drill roads at I' and ends at MDWs 17-08 b, c. The drill road winds above mined longwall panels 14 through 17. The overburden thickness to the B-Seam varies from 1,450 to 1,600 feet. The traverse was first in weathered and fractured siltstone, claystone, and sandstone bedrock of the Barren Member of the Ohio Creek Formation, then changed to colluvium and light gray to brown soil as much as 3 to 5 feet deep. The weathered and fractured bedrock looked similar to its appearance prior to mining, except that it looked somewhat more weathered. No subsidence features were observed. 4.14 Traverse M-M' Traverse M-M', which begins at fork in the drill roads at I' and L and ends at the fork in drill ' roads in Sylvester Gulch, goes above the southern edge of mined longwall panel 14, above mined longwall panel 15, and ends above the northern edge of mined longwall panel 16. Overburden ' depth to the B-Seam varies from about 1,000 to 1,650 feet. The traverse was through light gray to brown soil and colluvium, as well as alluvitm in the ' Sylvester Gulch drainage. No subsidence features were observed. ' The Twin Ponds (ponds P27-2 and P27-3 and USFS Water Resources numbers 188 and 154 respectively) are located above the head gate pillars of mined longwall panel 15. Although ' detailed analyses were not made, the water levels in the Twin Ponds were observed to be similaz to what they were in July 2004 and in the years prior to mining. The ponds, which are located in ' about 1,150 feet of overburden to the B-Seam, are about 50 feet in diameter and 3 to 5 feet deep. The estimated depth range of the clay /silt alluvium and colluvium beneath the ponds is 50 to 100 feet. 831-032.710 Wdght Water Engineers, Inc. Page 29 November 2005