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Since no water contribution was found in the Pictured Cliffs Sandstone while drilling, T <br />40 and S values cannot be determined from well testing. However, porosity and <br />permeability can be accurately determined by laboratory analyses. A detailed lab <br />analysis of a core from the top of the Pictured Cliffs Sandstone has been included as <br />Exhibit G. <br />The Pictured Cliffs Sandstone has an effective porosity of 14.07 percent and an effective <br />permeability of zero. Permeability was analyzed with respect to water, air, kerosene and <br />hydrogen (Exhibit G). Also, the Pictured Cliffs Sandstone is dry downdip of the mine <br />next to the Animas River indicating no general flow in the sandstone toward the river. <br />The one spring noted on revised Map 4 -3 (Mine Hydrology Map) is from a fractured <br />system in the exposed sandstone, based on a visual observation. <br />Substantial water was encountered when drilling hole 82 -4 from the interval 383 feet to <br />390 feet. As can be seen from the attached electrical logs, this strata (See Log IOB.) is <br />not a sandstone but laminated sandy shale. By reference to logs on Holes IOB and 82 -1, <br />one can see that the water is not available in other drill holes at this interval. <br />Consequently, the water is likely to be flowing from a fracture system. <br />Also, water is encountered in the coals and coal- overburden interfaces. Water <br />encountered in drill Holes 17B and 82 -5 are representative of the groundwater found in <br />the coals and interfaces. Holes 17B and 82 -5 are monitored for water levels and quality; <br />the results of which are included in the reporting for this permit. Ground -water <br />measurements have been shown in Exhibit G. <br />In summary, field observation and laboratory analyses indicate the following: <br />1) Water of pumpable quantity has been encountered in isolated drill holes and is <br />found in fracture systems or lenticular siltstones. These systems are perched and are <br />expected to bleed down with time when pumped because of the lenticularity of the strata. <br />2) Water is encountered in the coal and interfaces. Typically, the flows are 1 to 3 <br />gpm and are of the quality so shown from lab analysis. <br />3) No water is found in the Pictured Cliffs Sandstone. The absence of permeability, <br />which is a transmissivity relationship, indicates that no definable water will infiltrate, <br />percolate or invade the sandstone from the mining operation. If water is available in the <br />open pores (14% porosity), it is definitely immobile. <br />4) There are no aquifers in the permit area or the areas adjacent to the permit area. <br />Refer to electric logs and strata identification. <br />Pit inflows were projected to be 100 to 200 gpm in the early pit development based upon <br />very generalized extrapolations from drill hole data. This contribution is comprised of 20 <br />to 30 gpm from coal seams and the remainder from fracture systems. During mining the <br />pit did not encounter flows of water from fracture systems or perched water. In order to <br />Abridged Permit Document 4-6 Feb 2008 <br />