2016-02-03_PERMIT FILE - C1981038 (2)

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42.04 APPLICATION FOR PERMIT FOR SDRFACE OR UNDERGROIIND MINING ACTIVITIES -- MINIMUM REQUIREMENTS FOR INFORMATION ON ENVIRONMENTAL RESOURCES. 2.04.6 Geology Description. (2) (a) (Cont'd.) horizons may also change drastically, making correla- tion difficult. The base of the barren member is ap- proximately 700 ft. above the top of the Rollins sand- stone and the total thickness varies greatly as a re- sult of topographic elevation and erosional geomorphol- ogy. The coal bearing member of the Mesaverde formation is stratigraphically between the Rollins sandstone and the barren member, with the approximate 700 ft, thickness completely present, except near the outcrop areas. The three principal coal seams within the Permit Area are the B, C, and D, in ascending order, from the top of the Rollins sandstone. The "B" coal zone directly overlies the Rollins sand- stone and is present in mineable thickness in the west- ern and southern portions of Lease C-37210. Toward the north and east, the "B" coal zone splits into several • thin, high ash coal seams. Affolter, et al (1980) pos- tulate a lagoonal or barrier island depositional envi- ronment, although evidence to the west suggests an in- terdistributary environment. Thickness ranges from a maximum of 10.2 ft. to non-deposition. The "B" seam has been previously worked at the Black Diamond, Dor- rance, and Converse abandoned mines. The "C" coal zone overlies the Rollins sandstone by ap- proximately 100 to 150 ft ., and is 60 to 100 ft. above the uppermost split of the "B" seam. Thickness ranges from 18 ft. plus, to less than 2 ft. The "C" coal zone commonly consists of upper and lower splits, with an irregular middle unit present. The "C" coal seam thickens to the north and undergoes local thinning and thickening. Due to the irregular extent, the coals within the "C" zone are considered unmineable at pres- ent conditions. The "D" coal zone overlies the Rollins Sandstone by 175 to 200 ft. and is 40 to 150 ft. above the "C" coal seam. The "D" coal zone consists of upper and lower splits, although locally, either coal seam is • Revised 08/01/84 Revised 10/01/87 20