Laserfiche WebLink
• The ground water inflow rate appears to be very low for all of the mines located in the Lumsden <br />Canyon area because there is currently no flow out of the many mine portals that daylight into the <br />canyon. Since the mine drifts (i.e., tunnels) follow the ore zone and the ore zone dips toward the <br />canyon, these mines are essentially self draining. As discussed below, the combined inflow into the <br />Whirlwind and Packrat workings is estimated to be 10 gpm or less. During previous mining operations, <br />this water was used to support drilling and other mining activities. Currently, the water appears to <br />collect and infiltrate into the sandstone formation in the lower portions of the mine. <br />Most of the ground water inflow probably originates from the lower Brushy Basin sandstone units <br />since they are located closest to the mine workings. If the lower Brushy Basin water were subject to <br />Colorado water quality regulations, such as a discharge from a mine, it would probably need to be <br />treated to reduce radium to less than the 5 pCi/L water quality standard. Once this water enters the <br />mine workings, its quality deteriorates further due to contact with the ore zone, which contains <br />elevated levels of uranium, radium, and trace metals. This is evident from water quality sampling <br />conducted by Umetco and the BLM of the Packrat and other nearby mines during the 1990s and more <br />• recent sampling of standing water within the Packrat Mine by Energy Fuels. Water quality data for the <br />various mine waters are compiled in Table E-2 of Appendix E. <br />7.1 Current Mine Conditions <br />Most of the water that has accumulated in the lower portion of the Whirlwind Mine appears to be <br />seeping from the decline where it intersects the lower portion of the Brushy Basin. Ground water can <br />be clearly seen seeping into the decline and then flowing down to the bottom of the Whirlwind <br />workings. The flow was estimated to be 1 to 2 gpm during a recent inspection. <br />Analytical data for two water samples collected from the decline within the Brushy Basin intercept <br />area in early May 2007 are presented in Table E-2. The first sample, called the Whirlwind Seep, had <br />levels of selenium (0.023 mg/L), uranium (0.0814 mg/L), and radium-226 (6.5 pCi/L) above some <br />regulatory standards plus an elevated arsenic concentration (0.024 mg/L). The second sample from the <br />Upper Whirlwind Sump in the Brushy Basin unit had similar concentrations of selenium (0.038 mg/L), <br />uranium (0.0993 mg/L), and arsenic (0.029 mg/L). Radium-226 was not tested in this sample. These <br />• <br />Whirlwind Mine 07 (rev. April 08) G-15 <br />