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<br />• Ground Water Quality <br />In Appendix 3-D of Snowmass Coal Companies permit application <br />a complete description of Hole #1 is given. The hole was drilled to <br />a total depth of 300 feet. The A, B, and C coal seams, the Rollins <br />Sandstone, and the Mancos Shale were encountered in this hole. <br />Approximately .25 GPM of water was encountered in this hole at a <br />depth of 140 to 165 feet. This depth corresponds to the layer be- <br />tween the A and B coal seams. According to the drill log the well was <br />cased the entire length of the hole and perferations were made in <br />the water bearing zone and at the bottom 20 feet. <br />The deteriorating quality of the water in the hole is due to the <br />to the completion of the well. When the water in the hole is allowed <br />to react with the Mancos Shale it tends to increase the TDS of the. <br />water from the increase in the concentrations of Calcium, Magnesium, <br />Sodium, and Sulfate. This problem could probably be corrected <br />with total evacuation of the water in the well before a sample is <br />taken, but as it will be seen, it is almost impossible to do this <br />using manual sampling techniques. <br />By knowing that the water level in the well is normally 100 feet <br />deep and the casing is 5 inches in diameter the volume of water in <br />the well is calculated to be 102 gallons. The sample tube that is <br />• used to draw water from this well is two inches in diameter and .4.25 <br />feet long. Therfore; thesample tube can hold .70 gallons of water. <br />If two to three volumes of water were taken out of the well prior to. <br />sampling it would be necessary to drop and retreive the tube 437 <br />times. Snowmass personel usually take 10- 15 tubes of water out of <br />the hole before sampling. This may be one reason why the water <br />quality in the well is deteriorating. <br />In order to correct this problem Snowmass is going to achieve <br />total evacuation of the well prior to sampling by droping a sub- <br />merisble pump into the well. As soon as the new data is received <br />the Findings will be forwarded to the Division. <br />Ground Water Field Data <br />Appendix 6 contains the field data that was obtained when each <br />of the ground wells were sampled. In addition, graphs of the water <br />level in each well verses time are included in this appendix. As it <br />will be noticed, it is almost impossible to define any trends in <br />these graphs. <br />A comparison of the field parameters show that the pH varies <br />accordingly with the time of year the samples were taken (higher in ~- <br />the winter and lower in the summer. The temperature of the water <br />u <br />