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especially when extrapolated from well tests. Well tests are often biased by fracture <br />systems and faults, which give erroneous T and S values. <br />Since no water contribution was found in the Pictured Cliffs Sandstone while drilling, <br />T 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 />Appendix 4-3(a) hereto. <br />The Pictured Cliffs Sandstone has an effective porosity of 14.07 percent and an <br />effective permeability of zero. Permeability was analyzed with respect to water, air, <br />kerosene and hydrogen (See Appendix 4-3(a)). Also, the Pictured Cliffs Sandstone is <br />dry downdip of the mine next to the Animas River indicating no general flow in the <br />sandstone toward the river. The one spring noted on revised Map 4-3 is from a <br />fractured 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 lOB and 82- <br />1, 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 <br />quality; the results of which are included in the reporting for these permit. Ground- <br />water measurements have been shown in Appendix 4-3b. <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 <br />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 <br />permeability, which is a transmissivity relationship, indicates that no definable water <br />will infiltrate, percolate or invade the sandstone from the mining operation. If water is <br />available in the open pores (14% porosity), it is definitely immobile. <br />L~ <br />Technical Revision 09 (v 1.0) 45 Revised 3/1998 <br />