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than the Denver Basin sandstone and siltstone aquifers. Due to the low permeability, the gneiss <br />and schist in the Schwartzwalder area do not even meet the definition of an aquifer. Id. <br />(E) The Schwartz Trend Is Not a Conduit Between the Mine Pool and Ralston <br />Creek. <br />Paragraph 27 of the Order found that future contribution from the Schwartz Trend is <br />inevitable because of the direction of the hydraulic gradient, but the Whetstone Report indicates <br />that fracture permeability decreases with depth in bedrock systems. Thus, contribution from the <br />Schwartz Trend is not inevitable. Moreover, faults may act as barriers to groundwater flow, and <br />faults or fractures are often sealed (or annealed) at depth. See Whetstone Report, Exh. 4, at 5-6. <br />(F) Mine Flooding Is a Recognized Remedial Strategy. <br />The Order relied on the Division's testimony that the situation at the Lokken Mine had <br />deteriorated by 2009, and Cotter became aware of the Division's position at the hearing. As set <br />forth in the Whetstone Report, Exh. 4, at 1-2, the Division failed to recognize that the major <br />source of copper at this mine was from mine tailings at the mine site, not the mine pool itself. <br />There are no such tailings at the Schwartzwalder Mine, and copper has not been detected in mine <br />pool water above the method detection limit for the last five years. While the principle of mine <br />flooding to reduce oxidation applies at both sites, the Lokken Mine is an acid sulfide system with <br />a pH near 2. In contrast, the Schwartzwalder Mine is a neutral pH system with high buffering <br />capacity and copper below detection. <br />The Whetstone Report provides additional information about other examples used by the <br />Division. At Summitville, Colorado, adit plugging has in fact successfully reduced copper <br />loading to surface waters. See Whetstone Report, Exh. 4, at 2. Moreover, the need for <br />refurbishment of parts of the Summitville system, as stated in the Division testimony at the <br />hearing, does not mean that bulkheading has been ineffective. Id. At the Wismut uranium mine <br />16