2015-04-23_REVISION - C1981014 (2)

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George V. Patterson, Energy Fuels Coal, Inc. Page 3 April 23, 2015 `potential" to be impacted due to its location. However, records document that the Thompson Well was out ofservice prior to Southfield mining operations. Since TR43 is not being approved at this time, the updated Table 11 should be incorporated into the permit with an MR, as should the record of the new Corley well. The Division is aware of, and accepts, the discussion regarding the Thompson well on page 2.04.7 -12 of the PAP. c) Impacts to Groundwater Quantity DRMS: The Division agrees with the general assertion made by EFCI, that the monitoring data that has been presented supports the predictions, however this is not sufficient for approval of TR43. As was laid out in the opening paragraph of this letter, the operator should provide a detailed analysis showing, among other things, that onsite impacts have been minimized and offsite impacts prevented, and should include... an evaluation of any impact trends which may exist in the available data. In the context of impacts to groundwater quantity, this will require that EFCI collect monitoring data from MWNW. EECL Referring to "available data "stated above, EECI's available data has been analyzed and trends evaluated. However, data from MW -NW is not available because the well is dry at the 353 ft depth bgs a mere 20 vertical feet above the roof of the Southfield mine workings. An evaluation of the available data and trends analyzed has been prepared by Weaver Engineering Services and is located in APPENDIX `A " attached to this submittal. DRMS: Currently water levels in MW23 are a little less than 10 feet higher than the screened interval in the Red Arrow coal seam. Water levels in MW65are approximately 700 feet above the screened interval in the upper and middle Jack O' Lantern seams. These two monitoring wells indicate that groundwater on either side of the mine has a head above the elevation of the mine workings. It is assumed that the workings have not completely filled with water yet; and in any case the workings are either relatively open or filled with unconsolidated rubble with a large pore volume, and at atmospheric pressure (at least in the vicinity of MWNW) since MWNW is not sealed. Therefore the local groundwater flow direction from these two monitoring points is probably towards the mine. MW 16 has been reported as dry, although the level indicated as dry is higher than previously recorded water levels, so further clarification is necessary. Using these two (or, if MW 16 can be clarified, three) data points alone it is not possible to make any meaningful assessment of the rate at which the mine workings are filling with water and the local hydrologic balance is returning to equilibrium. EM: Mine inflows were monitored and recorded throughout the life of mining operations and the post mining reclamation period (Annual Hydrology Reports). As documented throughout the Annual Hydrology Reports, approximately 85% of inflows were pumped and accurately metered and the minor balance was estimated by qualified