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described, the drillers propose to first cement in a 8 inch diameter steel conductor pipe from the surface <br />through the alluvium zone of sand, gravel and boulders (projected to be 52 to 58 feet below the surface), <br />then drill to the floor of the Southfield mine workings with a 7.5 inch drill bit. Next, a 4.5 inch steel <br />casing will be installed to the floor of the mine workings. To penetrate the rubble zone in the mine <br />workings, the drillers will weld a 4.5 inch drill bit onto the end of the 4.5 inch well casing, rotating the <br />casing as necessary to penetrate the rubble zone. When the floor level of the mine workings is reached, <br />the 4.5 inch casing with the bit attached will permanently remain in place. This technique has been used <br />before by the drillers and they have a high level of confidence of success. Rubber packers are set on the <br />4.5 inch casing about 20 feet above the rubble zone and bentonite slurry will fill the annulus from the <br />packers to the surface. A tremie pipe will be used to inject the bentonite slurry into the annulus. The <br />bottom 20 vertical feet of the 4.5 inch steel casing will have prefabricated perforations encompassing the <br />bottom section (at the floor of the mine workings) of the casing to allow water to flow into the casing if <br />water is present. The perforations in the casing are 1/2 inch diameter, four (4) holes per lineal foot arranged <br />in a spiral configuration. The 4.5 inch steel casing will extend from the surface to the floor of the <br />Southfield mine workings and will provide access to the mine workings to determine if water is present, <br />to monitor the well and acquire water samples if necessary. Due to the potential of methane gas in the <br />mine workings, nitrogen gas will be used with the drilling operation. <br />To minimize disturbance on the ground surface, the disturbance boundaries that access the <br />existing MW -NW monitor well have been extended to the proposed site of MWNW-2. Disturbance area <br />within the additional disturbance boundaries for access to MWNW-2 and for the drill site "pad" (for the <br />drilling equipment) is approximately 0.8 acre. <br />Concerning applicable rules by the Division of Water Resources (DWR) for monitor wells, Form <br />GWS -46 "Monitor/Observation Water Well Permit Application" (recommended by the DWR), is <br />concurrently being submitted to the Division of Water Resources (DWR) in Pueblo, Colorado. A copy of <br />the Form GWS -46 application is included herein in Appendix "C" with this submittal. <br />Map 12, "Mine Area Surface & Groundwater Hydrology" has been revised to depict the location <br />of the proposed MWNW-2 site and is included in Appendix "D" with this submittal. Likewise, the <br />"Southfield Mine Permanent Closure Map" which depicts the Southfield mine underground workings has <br />been updated to show the proposed location of the replacement monitor well (MWNW-2) and is also <br />included in Appendix "D". Updated replacement pages for the approved permit document are included in <br />Appendix "E". <br />The availability of the drillers is limited and they are pressing to start the project as soon as <br />arrangements can be finalized. Accordingly, EFCI requests that the Division reviews and processes this <br />revision request as soon as possible. <br />If you have questions or require further information, please contact me. <br />Sincerely, <br />_� � <br />eorge V > atterson <br />Energy Fuels Coal, Inc. <br />