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Bob Liddle -9- Dacemher 2, 1981 <br />5) The outcrops and subcrops of the two overlying sandstone aquifers <br />should be plotted on a topographic map. A determination of the recharge and <br />discharge characteristics of these aquifers should also be made to determine <br />if the aquifers are recharged from the North Thompson Creek Alluvitim or <br />discharging to the alluvium and stream. <br />6) Snowmass Coal Company should conduct a spring survey of the entire <br />area to be undermined by both the 1/I and b3 mines, the areas which may be <br />effected by the subsidence angle of draw, and of the loadout area. All perennial <br />and ephemeral springs should be located on a geologic map. A description of <br />the source of water (i.e., fault, fracture, landslide body, bedrock contact, <br />~ete.) and the geologic formation from which the spring eminate. The flow rate, <br />pH, electroconductivity and temperature should be taken on each of these springs <br />on a quarterly basis. An assessment should be made of the contribution of <br />these springs to surface water flows and the impacts of mining on these springs. <br />Conducting a spring survey at this time of year will be next to impossible. <br />A preliminary survey, however, could be conducted from areal photography of the <br />mine area and the loadout area. <br />7) The mine inflow diagram (Figure B-2, Section 3.0) within the responses <br />is inadequate. This map is only for a limited area within the b1 mine in~the <br />A-seam, no map is provided showing inflows into the !13 mine in Anderson Seam. <br />New mine inflow maps should be drafted on updated mine workings maps of the kl <br />and b3 mines. All point inflows and seeps within accessible areas and all dis- <br />charge points from mined out areas should be plotted on these maps, along with <br />the measured or estimated rates of flow. Surface streams and the topography <br />(i.e., Maps A and B of Subsidence section) should be super-imposed over the mine <br />workings maps for reference. A description of the fluctuation in observed flow <br />rates; the pH, conductivity and temperature and the source of each inflow or <br />seep (i.e., faults; joints; fractures; cleating; weeping floor, roof or face; <br />etc.), should accompany and be keyed to the mine inflow map. The mine inflow <br />maps and descriptions are needed to evaluate the present impacts of mining on <br />the hydrologic balance. The information gained in this mine inflow study should <br />be used in projecting the potential future impacts of mining and included in the <br />section titled Hydrologic Consequences of Mining. A study of the quality and <br />consumption of water within the mine area should be conducted by Snowmass. <br />This study should include the amount of imported water, water made in the mine, <br />water discharged from the mine, water consumed by evaporation in surface sediment <br />pond, and the quality and quantity of water discharges into North Thompson <br />Creek. The studies of water quality and consumption should be used in the <br />evaluation of impacts of the mine on water rights downstream of the mine and on <br />the need for alternative sources of replacement waters to downstream uses. <br />8) The monitoring section should include the monitoring of mine inflows <br />and water consumption within the mine area. This monitoring should include a <br />yearly submittal of a mine inflow map with description of inflows, and a water <br />balance study for the mine area, as outlined in the above section. <br />