2012-08-31_HYDROLOGY - C1981014 - Laserfiche WebLink

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energy fuels coal, inc. southtield mine • post office box 459 • tlorence, colorado 81226 • (719) 784 -6395 August 28, 2012 Ms. Janet Binns — Reclamation Specialist Colorado Division of Reclamation Mining & Safety 1313 Sherman St — Room 215 Denver, CO 80203 RE: Monitor Well MW -NW - Broken Cable Removal Energy Fuels Coal, Inc. — Permit No. C -81 -014 — Southfield Mine o cerveo AEG 312412 Of R 50060, pWi W ppr►n9 & L'/ Dear Janet Binns: This is to advise that the broken 1/16 inch diameter cable (354 feet) that was coiled in the MW- NW monitor well at the Southfield mine was removed August 27, 2012. Two photos showing the removal tool and the coiled cable after removal are enclosed. The tool used was a modified version of that which was suggested by Kent Gorham, formerly with the DRMS. The fabricator added a scissor action to the tool that allowed the tool to close on the entangled coils for successful removal. Pursuant to the removal of the cable, an electronic water probe, having been pretested for operation, was lowered to the 356 ft level in the well. The probe was raised and lowered approximately 10 ft a dozen times in the range of the 356 ft well level to assure any contact with potential water in the well. As had been reported in previous water probing reports, no water was detected in the MW -NW monitor well at or above the 356 ft level in the well. As further assurance, it was noted that there was no moisture on the end of the probe when it was retrieved from the well. The DRMS concurred (letter of August 8, 2012) "that there is hydrologic connection of the well with the mine workings". This was evidenced from the 1,500 gallon water test dumped down the well on April 17, 2012. It should be noted here that the well at issue was formerly used as a dewatering well in the 1s North Section of the mine. As a `dewatering' well the bottom of the well (380 ft depth) would be positioned at the floor level (or below) of the mine, not at the roof level, for dewatering purposes. Borehole drill logs identify the thickness of the coal seam near the MW -NW as 5.5 ft. This would place the roof level of the mine at the 374.5 or 374 ft level of the well casing. Given that the measured depth to the current obstruction in the well is 356 ft from the top of the well, that leaves a distance of 18 or 18.5 vertical feet of void area between the obstruction and the projected roof level in the mine. Given that the mine was not pillared in that area and considering that the well is located in an `intersection' of a mine entry and a crosscut, an 18 foot void of roof fall or caving is not unusual. Energy Fuels reiterates that the 356 ft level in the well, being open to flow to the mine void, is adequate for monitoring and sampling mine water and concurs with the statement in the DRMS inspection report of April 17, 2012, " - - based on the previous fact that this well entered the mine workings and that our findings from this inspection that this well serves the purpose of detecting, measuring and sampling water in the [potential] flooded Southfield mine workings".