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~~ <br />southwest of the existing New Elk Mine workings. Both the Allen and <br />Idaxwell coal seams lie more than 300 ft. below the Purgatoire River. The <br />coal seams discharge to the center of the Raton Basin. No springs or <br />seeps have been identified which discharge from the coal seams. There <br />are no water wells completed in the coal seams. <br />The water quality data appears in Exhibit A of the renewal application. <br />Water from well LA 221A is believed to be representative of the <br />undisturbed waters in the coal seam. Water pumped from well LA 264 is <br />believed to be produced from a thin fracture zone in the overburden at a <br />depth of approximately 72 feet, as discussed previously. Though the <br />water sample from this well represents a zone high in the overburden, the <br />composition and total concentrations are very similar to the <br />corresponding parameters from well LA 221A completed in the coal. This <br />observation suggests a uniform water quality throughout the profile. <br />Both the coal water and the overburden water show a similar chemistry. <br />The water is a sodium-bicarbonate type water. The coal seam has higher <br />concentrations of carbonate, total iron, total manganese, total zinc, and <br />a slightly higher pH than found in the overburden water. Sulfate <br />concentrations in the coal seam were slightly lower than in the <br />overburden. Data on other trace metal concentrations were not provided. <br />Analysis of the water flowing from the fracture zone encountered in the <br />Second Right entries resembles that of the waters from wells LA 221 and <br />LA 264. It too is a sodium-bicarbonate type water with a TDS value of <br />802 very similar to the values for wells LA 221 and 264. <br />C. Ground Water - Alluvial Aquifers <br />Investigation of the alluvial ground water along the Middle Fork and main <br />stem of the Purgatoire River was conducted by drilling eight holes (3 at <br />the New Elk Mine, and 5 at the Golden Eagle Mine) through the alluvium to <br />bedrock and excavating several back hoe pits. Ground water was <br />encountered only in the alluvium in direct contact with the river. The <br />thickness and lateral extent of the saturated alluvial material is <br />limited. The water table depth in the alluvial wells ranged from about 4 <br />to 5 feet below the ground surface, and was largely controlled by the <br />water level in the river. <br />Drill holes and backhoe pits encountered no ground water in the strath <br />terraces and no prominent springs were observed near the contact between <br />the strath alluvium and bedrock. This indicates that the strath terraces <br />do not contain a water table aquifer and that these deposits are not <br />hydrologically connected to the alluvial terraces adjacent to the Middle <br />Fork and mainstem of the Purgatoire River. <br />Auger hole tests were performed to determine the hydraulic conductivity, <br />(permeability) of the alluvial flood plain materials. The permeability <br />determined from the auger hole tests ranged from 0.014 ft/d to 2 ft/d. <br />Attempts to conduct an auger hole test at one hole failed because the <br />permeability was too high. A pump test was performed on that hole, and <br />from the observed drawdown, the permeability was estimated to be about <br />1,880 ft/d. <br />-15- <br />