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

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42.04 APPLICATION FOR PERMIT FOR SURFACE OR UNDERGROUND MINING ACTIVITIES -- MINIMUM REQUIREMENTS FOR INFORMATION ON ENVIRONMENTAL RESOURCES. 2,04,7 Hydrology Description. (1) (b) (Cont'd.) possibility of being used as a groundwater resource in the foreseeable future. Although a degree of correlation is suggested on Map 10-1, the continuity of the perched groundwater above the "D" coal seam is very unreliable. The intent of the fence diagram is to show that the saturated inter- val below the "D" coal seam is more highly developed than the perched horizon, which is in agreement with the regional stratigraphy of the permit area. colluvial Near Surface Storage Within the lease area, there are several well developed colluvial/alluvial deposits. These deposits are con- tained in the mixtures of clay, sand, and silt with some large rock fragments. These strata were formed by slow downslope movements of near surface materials, lo- cally reworked by fluvial processes. The lateral ex- • tent of these strata is shown on Map 2-2, where the colluvial/alluvial quarternary deposits have a symbol "Qac". The most significant of these deposits is pres- ent in the Steven's Gulch drainage, around and upstream of the CWI wellfield. Another area covered with these sediments is developed in the central portion of the East Roatcap Creek. The greatest thickness of the col- luvial/alluvial sediments (97 ft .) was reached in Well ~6SG-A, installed in Steven's Gulch wellfield. The thickness of these sediments in the other areas is not believed to be grea[er [han 100 ft. Unconsolidated quarternary deposits are the primary sources of springs and seeps within the Permit Area. Typically, discharge is small (less than 5 gpm) and sa- linity low to moderate (100-500 umhos - refer to Ground Water Appendix, Volume 4). The recharge-discharge re- lationships are functions of geomorphology and seasonal variations in precipitation. Recharge occurs as a re- sult of percolation and infiltration in the upland areas, and discharge occurs usually near the topograph- ically lower stream drainages. Many of the discharges are also ,associated with small scale mass wasting • Revised 12/26/84 Revised 10/01/87 39