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Whirlwind Mine Groundwater Characterization Report <br /> 4.2.1.2 Whirlwind Decline <br /> As mentioned, the Whirlwind Decline was constructed in 1979 as an access tunnel to uranium <br /> ore bodies known to exist (by exploration drilling) in the Top Rim sandstone of the Salt Wash <br /> Member. The decline was collared in the Brushy Basin Member and driven approximately <br /> 3,200 ft at a minus 6% grade. As described in the DRMS Whirlwind Mine Permit(Exhibit G), and <br /> the BLM Plan of Operation (Exhibit 8) groundwater seeping into the Whirlwind Decline <br /> originates where the decline intersects the lower portion of the Brushy Basin. The flow was <br /> estimated to be 1 to 2 gpm. <br /> Reconnaissance by WWL in June 2008 showed seepage in the decline at four general <br /> locations: 1) Upper Decline, 2) Lower Decline, 3) Sump Area, and 4) Drift Area. Detailed <br /> descriptions of WWL's observations are in the letter report submitted to DRMS on May 5, 2009 <br /> (WWL, 2009). The seepage observed in the Sump and Drift areas (Salt Wash Member) were <br /> interpreted to be local discharge of stored mine flood waters that had flooded the working as a <br /> result of years of mine inactivity (1982 to 2007). Seepage observed in the upper decline was <br /> minor, enough to cause moist to wet conditions of Brushy Basin shale and mine road base <br /> materials at a location approximately 200 ft from the portal. The material showed wet conditions <br /> for a distance of about 40 ft down the decline. No concentrated flow was observed. It was <br /> theorized that this moisture was related to the contact between the surface colluvium and the <br /> underlying Brushy Basin Member. <br /> Seepage in the lower decline was observed where a sandstone bed or lense intercepts the <br /> decline at an elevation of approximately 6,940 ft. The sandstone unit was less than or equal to <br /> 5 ft thick and interpreted as a lower sandstone lense (channel sand)within the Brushy Basin <br /> Member. Characteristic to the Brushy Basin, the channel sand is overlain and underlain by <br /> sequences of maroon-colored mudstone with light gray to green mottling. The point of highest <br /> elevation where seepage was observed was covered by timber supports on the right rib. Further <br /> down the decline the sandstone unit and contact with the lower mudstone was visible. <br /> Seepage in the decline at this sandstone intercept is somewhat diffuse and is only partially <br /> channelized on the decline floor along the right rib. Observed flow was estimated to be 1 to <br /> 2 gallons per minute (gpm). Several areas of obvious flow were observed on the sandstone <br /> face, at the base of the sandstone, or near the contact with the underlying mudstone. These <br /> Western Water& Land, Inc. 16 <br />