2016-03-04_REPORT - C1981014 - Laserfiche WebLink

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2015 Annual Hydrology Report Energy Fuels Coal, Inc. - Southfield Mine 3.0 GROUNDWATER AND SURFACE WATER MONITORING RESULTS 3.1 Groundwater Monitoring Results Mine Area In the Mine Area, groundwater occurs in surficial alluvial/colluvial deposits and as water table conditions in the sequence of sedimentary rocks corresponding to the Vermejo, Raton, and Poison Creek formations. Due to semi -arid conditions and the limited extent and continuity of the alluvial/colluvial deposits, these units do not store or transmit appreciable quantities of groundwater in the general mine area. There is limited lateral or regional continuity of potential water -bearing units due to variable lithology and significant cross -bedding and inter -bedding within the bedrock units. As a result, there are no known aquifers in the mine area, and bedrock groundwater occurrences are limited to isolated units and zones that have sufficient local recharge and characteristics that allow it to store and transmit water. Therefore, only isolated shallow perched groundwater zones may develop. Additional "minor" groundwater storage may occur in abandoned and flooded mine workings, which serve as small collection and storage reservoirs as well as for origination of fracture flows. Additional supporting information may be found in Section 2.04.7 of the Southfield permit application. In the mine area, the approved groundwater monitoring program included, prior to approval of TR - 43, the following monitoring wells, shown on Map 12, Mine Area Surface and Groundwater Hydrology: WELL LOCATION I.D.* MW -16 E'/2NW'/4, Sec 30 MW -23 E'/2SW'/4, Sec 19 MW -65 W'/zSW'/4, Sec 24 MW -NW W'/zSW'/4, Sec 19 DEPTH/COMPLETION GEOLOGIC COMPLETION ZONE ZONE 136'/ 106'-136' Jack O'Lantern Coal Seam 179'/ 149'-179' Red Arrow Coal Seam 1448'/ 968'-988' Jack O'Lantern Coal Seam 380' / 360'-380' Red Arrow Coal Seam (mine void) *All wells sealed and reclaimed in Nov. 2015 The approved groundwater monitoring schedule, prior to approval of TR -43, required semi-annual well sampling, typically conducted during the second and fourth quarters. Field measurements and laboratory data for active monitoring wells are summarized in the following discussions. Field and laboratory data for 2015 are provided in Appendix C. Measured water levels for all wells are summarized in in Appendix A, on Table 3, Monitor Well Water Levels for years 2000-2015. Past well water level data for all monitoring wells are documented in AHR's on file at the Division. All available water level data are presented graphically for the four monitoring wells in Appendix A, on Figures 1, 2, 3, and 4. Page 3