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

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42.04 APPLICATION FOR PERMIT FOR SDRFACE OR UNDERGROUND MINING ACTIVITIES -- MINIMUM REQUIREMENTS FOR INFORMATION ON ENVIRONMENTAL RESOURCES. • 2.04.7 Hydrology Description. (1) (b) (Cont'd.) the Paonia study area, and its water-quality analysis is atypical of analyses of water in the Mesaverde For- mation.". Well completion data, summarized in Table 4-A in Appendix 4, shows the casing is set to approxi- mately 5 ft. above the "D" coal seam. Analysis of the geophysical log of GR77-7 (U. S.G. S. open file report 78-540) depicts a 35 ft, [hick sandstone layer at 150 ft., which coincides with the upper perforated inter- val. It is believed that although the surficial mate- rial is approximately 40 ft. deep, the water probably originates in the colluvium or colluvial water re- charges of the shallower Mesaverde Formation litholo- gies. The depth of water in this well was approximate- Ly 10 ft. higher in 1984 than in 1983, suggesting a climatic relationship rather than deep bedrock origin for this well. The alternating lenticular channel sandstone and en- closing overbank claystone lithologies within the Upper • Mesaverde Formation have the potential to create perched water table conditions within the permit area. These conditions, which are a function of the deltaic- fluvial depositional environment, are charaterized by confined, saturated horizons of localized lateral and vertical extent within low porosity, unsaturated inter- vals. These perched, confined horizons may exhibit ar- tesian conditions; however, flowing conditions were not observed within the permit area. The perched horizons may be recharged from the colluvi- al-bedrock interface (as in DH-47 and GR77-7) or by fault-fracture zones present within the permit area. Superimposing Maps 10-1 and 2-8 (fence diagram of sat- urated intervals and exposed and inferred structures, respectively) suggest a slight degree of correlation between exposed and inferred structures and perched groundwater occurrences. Where exposed in outcrops, they may be recharged by meteoric processes. The erratic location of these perched groundwater oc- currences, low transmissivity and permeability, and ab- sence of development and exploitation diminishes the Revised 12/26/84 Added 03/07/85 Revised 10/01/87 38