Laserfiche WebLink
• Lorencira Carron Mine - Graundwnter Technical ReDOrt <br />three proposed wells at the MW-3 site were not installed, since groundwater was not encountered. <br />Data from the drilling at MW-2 and MW-3 indicates that the aquifer is discontinuous, at best. <br />Ciruela Coal <br />Drilling of the Ciruela seams was at locations MW-1, MW-lA, MW-2, and MW-3. Drilling in <br />these areas encountered limited water (<5 gpm) in the location MW-lA. Drilling at the MW-1 <br />location was moved to the MW-lA location after the initial boring determined the coal was <br />pinched out at the MW-1 location. Drilling in the MW-2 and MW-3 locations did not encounter <br />any water. Two of the three wells in the MW-3 site were not installed, since water was not <br />encountered. <br />Interburden <br />Drilling in the second interburden zone (Primero) did not indicate large quantities of water in this <br />zone. Water was encountered in the drilling for MW-4 at approximately 25 feet below grade, but <br />this well is located in an alluvial valley, and the alluvium is thought to be the source of this water. <br />Increased production of water was not noted as the boring progressed. Wells were set in the <br />sandstone immediately overlying the Primero, since water production more than 5 gpm was not <br />• noted during drilling. The location MW-6 encountered water at approximately 110 feet below <br />grade, but groundwater flow from this formation was also nominal. The location MW-5 <br />encountered groundwater in the boring at 50 feet below grade, and a flow of 125 gpm was <br />estimated from this zone. This zone is also thought to represent a fractured sandstone that is in <br />contact with the alluvium; therefore, during the installation of these wells this zone was cased off. <br />Well screens at these locations were set in the consolidated sandstones overlying the coal. <br />Primero Coal <br />No increase in water flow was noted during drilling through the Primero Coal at well locations <br />MW-4, MW-5, and MW-6. All wells in this zone were set as per the aforementioned <br />methodology. <br />Underburden Wells <br />Underburden wells were installed in the sandstone encountered below the Primero Coal at well <br />sites MW-4, MW-5, and MW-6. With the exception of MW-5, no increase in flow was noted <br />during [he drilling of this zone. At MW-5 an increase of 5 gpm was estimated during the drilling <br />of this well through this zone. <br />• <br />Groundwater 475\December 9, 1996 12 <br />