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Public access is controlled and limited to certain defined areas within the Permit • Boundary used for accompanied tours. Teller County Land Use Zoning is agricultural (A-1) within the District with a special overlay district (Cripple Creek Mining Overlay District) recognizing that this is an area where mining has historically occurred and will most likely continue to occur. 4.4 Geoloev There have been no changes in the description of the general site geology from that provided in the Amendment No. 8 application. 4.5 Geochemistry and Ground Water Ouality The District and surrounding azeas aze drained through historic drainage tunnels created in the late 1800's and eazly 1900's to lower the ground water table in order to facilitate underground mining. The Carlton Tunnel is the primary point of water outflow from the District and surrounding azea. The drainage tunnels lowered the ground water in the District to an elevation of approximately 7,000 feet AMSL, or approximately 3,000 feet below the ground surface. The Cazlton Tunnel continues to flow at approximately 1,500 gallons per minute. CC&V holds a CDPHE, Water Quality Control Division ("WQCD") dischazge permit for the Tunnel. . In 1998 and again in 2000, Shepherd Miller Inc. ("SMP') and Adrian Brown Consultants ("ABC") conducted extensive investigations of the ground water hydrology and geochemistry of the District for Amendment Nos. 7 and 8. These studies were reviewed and approved as part of the referenced Amendments. The results of the studies aze summarized below: The 1998 study reached three pertinent conclusions: Surface mining activities aze not expected to cause a meaningful change in the hydrologic behavior of [he system; Any potential acid generation that might occur at the surface or in historical underground mines will be neutralized along the subsurface flow to the ground water system that eventually flows to the Cazlton Tunnel; and Zinc concentrations in the Cazlton Tunnel aze affected by hydrological and geochemical processes but remain low and are expected to remain low in the future. The results of the Amendment No. 8 investigations indicate the following: ^ As with Amendment No. 7, Amendment No 8 surface mining activities aze not expected to cause a meaningful change to the hydrologic behavior of the system; • The overburden mined under Amendment No. 8 is not expected to be acid generating; 6