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~ ~ iii iiiiiiiiiiiii iii <br />.XBOw <br />Sanborn Creek Mine <br />December 23, 1997 <br />William J. Carter <br />Environmental Protection Specialist <br />State of Colorado <br />Division of Minerals and Geology <br />1313 Sherman Street, Room 215 <br />Denver, Colorado 80203 <br />RECEIVED <br />~aa i 5 ~sse <br />Division of Minerals 8 Geology <br />Fax: (303)832-8106 <br />Re: December Quarterly Sampling for Groundwater Monitoring Well SC-2 <br />Dear Mr. Carter: <br />As we discussed by telephone this morning, during the routine December Quarterly sampling for <br />Groundwater Monitoring Well SC-2, we have encountered difficulty in collecting the required <br />sample. We have been able to measure the depth to water in the well with the small~iameter <br />electrical cable, and the depth appears to be about as expected at ] 59 feet. <br />However, when attempting to lower the baler in the 2-inch, PVC-cased well, the baler apparently <br />does not reach the water level. Additionally, the pull on the rope when retrieving the baler indicates <br />the baler has the potential to stick in the well. We baled the well with a smaller~iameter baler, and <br />were successful in obtaining a sample. Apparently, there is some obstruction, such as possible <br />ciushing of the casing, that has occurred since the September Quarterly sampling. <br />Groundwater Monitoring Well SC-2 was drilled from November 7 to November 11, 1990 to a depth <br />of 610 feet into the Rollins Sandstone below the coal seams. The bottom 110 feet of the hole was <br />grouted and the monitoring well was installed to 500 feet. While drilling, water was encountered in <br />a rider coal seam in the vicinity of the D-Seam coal at a depth range from 127 to 130 feet. The main <br />D-Seam coal was logged at a depth range from 135 to 161 feet. <br />After completion of Well SC-2, a hole was drilled nearby to a depth of 168 feet. Well SC-3 was <br />installed to 145 feet in this hole. After completion of Well SC-3, a hole was drilled near the portals <br />to a depth of 230 feet into the Rollins Sandstone. Well SC-i was installed to 230 feet in this hole. <br />After completion of Well SC-1 on November 19, 1990, monitoring of the wells was started on <br />November 29, 1990. <br />P O Box 5 3 5 Somerset C o l o r a d o 8 1 4 3 4 U S A <br />TEL (9 7 0) 9 2 9- 5 1 2 2 FAX (9 7 0) 9 2 9- 6 2 6 1 <br />