2025-04-29_HYDROLOGY - M2007044

• Permit No: M2007044
• IBM Index Class Name: Hydrology
• Doc Date: 4/29/2025
• Doc Name: Hydrology Report
• From: Energy Fuels Resources Inc
• To: DRMS
• Annual Report Year: 2025
• Report Quarter_Month: 1
• Permit Index Doc Type: Hydrology Report
• Email Name: ACY
• Email Name: THM
• Media Type: D
• Archive: No

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WHIRLWIND MINE, PERMIT NO. M-2007-044
FIRST QUARTER 2025 HYDROLOGICAL REPORT
Attachment 2. Whirlwind Decline
Monitoring Sample Inflow Rate(') Field pH Temperature Dissolved Specific Oxygen-
Date Location (gpm) (s.u.) (deg. C) Oxygen Conductance Reduction Comments
(mg/L) (US/cm) Potential (mV)
3/10/2008 WW Sump 2.4 8.30 11.0 NM NM NM See Table 1
6/19/2008 WW Sump 2.8 10.26 11.5 0.78 592 114 See Table 1
9/8/2008 WW Sump 2.2 9.11 11.0 8.48 649 62 See Table 1
12/16/2008 WW Sump 1.7 8.75 10.7 5.22 609 149 See Table 1
3/5/2009 WW Sump 2.1 8.52 11.1 8.24 618 151 No analytical samples collected
4/20/2009 WW Sump 2.2 8.41 11.2 6.68 626 177 No analytical samples collected
8/11/2009 WW Sump 1.6 8.76 11.9 6.44 599 152 No analytical samples collected
12/1/2009 WW Sump 1.4 8.61 11.5 6.54 624 160 No analytical samples collected
2/2/2010 WW Decline 2.0 7.06 11.3 7.02 597 170 No analytical samples collected
4/21/2010 WW Decline 1.9 8.07 12.3 6.76 576 201 See Table 1
9/8/2010 WW Decline 1.7 8.65 11.9 4.53 592 133 No analytical samples collected
11/4/2010 WW Decline 3.4 8.49 11.6 2.22 578 207 No analytical samples collected
2/7/2011 WW Decline 1.7 8.49 11.3 2.26 590 151 See Table 1
6/20/2011 WW Decline 1.2 8.17 11.7 2.42 620 159 No analytical samples collected
8/20/2011 WW Decline 1.3 8.54 11.6 2.54 644 163 No analytical samples collected
10/25/2011 WW Decline 1.0 8.48 11.5 2.63 618 157 No analytical samples collected
11/9/2011 WW Decline 1.0 8.19 11.5 3.09 631 234 See Table 1
3/28/2012 WW Decline 0.7 8.32 11.5 1 2.41 592 173 See Note 2 3
(1) From First Quarter 2008 to Fourth Quarter 2009, the inflow rate was estimated over the quarter by calculating the volume of water pumped out of the mine and treated
and estimations of the volume of water evaporated off the untreated water tank and brought out of the mine as moisture in waste rock, ore, and ventilated air.As of the First
Quarter 2010, water inflow is estimated based on the approximate water elevation and the void volume of the mine workings.
(2)Access to the mine was temporarily restricted as of the third quarter 2012.
(3)Access was regianed in mid-2023, however no significant flows have been identified.Flow rates, field parameters, and other monitoring requirements will be completed and
reported in accordance with the permit(Exhibit T, Section 10.2 ) and can be collected safely.