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its Notice and requests that the Board proceed with the enforcement hearing set for <br />the Board's November 17-18, 2010 meeting. The Board's August 11 Order is in <br />effect and Cotter is required to comply with it. <br />BACKGROUND <br />This matter concerns Cotter's mining operation contaminating Ralston Creek <br />with uranium. Ralston Creek flows into Ralston Reservoir, a drinking water source <br />for Denver and Arvada. Given the public health and safety issues involved, it is <br />important to summarize some of the Board's findings and conclusions contained in its <br />August 11, 2010 Order specific to the mine pool; the Board made findings and <br />conclusions about the alluvial fill as well. <br />In its August 11`" written order, the Board found among other facts, the following: <br />1. Cotter's mining operation, the Schwartzwalder Mine, is located adjacent to Ralston <br />Creek and flows into Ralston Reservoir, which is a drinking water source for Denver <br />and Arvada. <br />2. Since Cotter shut down its water treatment system in 2002 and stopped re- <br />circulating water from Sump No. 1 in 2008, uranium levels in Ralston Creek have <br />exceeded regulatory limits. <br />3. Although Cotter agreed to capture and treat some of the alluvial ground water, it <br />did not agree to draw down and treat the mine pool. <br />4. The mine pool was created when Cotter allowed the underground mine to flood. <br />The mine pool now contains an estimated 144 million gallons of water laden with <br />elevated levels of uranium, molybdenum and other dissolved solids. <br />5. At the hearing, Cotter argued that the mine pool was not seeping because Cotter <br />theorized that the pool was contained. However, Cotter's statements were <br />inconsistent with prior statements it made in its April 2010 Environmental Protection <br />Plan in which Cotter stated that the mine pool was a possible conduit for uranium into <br />Ralston Creek and that the mine pool could be contributing 0.8% to 8% of the alluvial <br />flow. <br />6. Other possible conduits include unplugged boreholes drilled by Cotter and the <br />Schwartz Trend, a geologic formation characterized by brittle fracturing and which is <br />the primary host for the uranium. <br />7. The hydraulic gradient of the mine pool water is now toward Ralston Creek and <br />Ralston Reservoir. It is an application of basic hydrology and scientific common <br />sense that the mine pool will migrate in the direction of the hydraulic gradient. <br />2