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• i (Page Z) MINE ID # OR PROSPECTING ID #: M-loon-On7 M-2c~o f -OV I INSPECTION DATE: r,-77-nt INSPECTOR'S INITIALS: nCS This inspection was conducted to evaluate the condition of the Dolores riverbanks through the Line Camp reach. Parties to the consideration of the Lined Camp Pit reclamation permit application have raised the concern that the riverbanks could erode during a flood and ultimately reroute the main channel of the river through the excavated pits. The Division of Minerals and Geology has evaluated the potential for such an occurrence and determined that the undisturbed buffer zones between the pit and the river are adequate to prevent river capture during a 700-year flood. Certain objectors to the Line Camp Pit application requested that the Division conduct this second of two pre-operational inspections in order to evaluate the riverbank conditions (the Division previously inspected this proposed piton March 15, 2001>. The Dolores River in the immediate vicinity of the Line Camp Pit is very straight, characteristic of a rifflelrun riverne setting with large bottom substrate size, minimal meandering, and swik flow during high water. Discharge of the Dolores River at the gauge in the Town of Dolores at the time of this inspection was approximately 700 cubic feet per second. The river was flowing well below the top of the banks and well below the ordinary high water line. A series of slight bends in the river were observed above, through, and below the Line Camp Pit reach. In each of these bends, it was observed that the energy of the river is focussed on the outside of the bend, and that bank cutting has occurred on the outside of the bends. The insides of each of the bends are characterized by gently sloping and stable riverbanks. The entire right bank of the river was inspected from a location north of the proposed gravel pits to the property line on the south. It was determined that that the entire riverbank adjacent to where the pits will be excavated is on the inside of a slight river bend, and that the riverbank is stable. South of the area where the pits will be, but still on the Line Camp property, the energy of the river shifts to the right bank. As this occurs, the Line Camp property riverbanks are being undercut and are unstable. The bank cutting continues into the Robinson property to the south. It was noted that the riverbank around the Akin residence on the opposite side of the river is an aggrading bank, and is stable. The left bank below the Akin house once again begins to cut. It was observed that the lowest or southernmost 400 feet of the Line Camp property riverbank is cutting. The property owner has attempted to eliminate bank cutting in certain locations though the placement of piles of river cobble and boulders on the riverside of the cutting bank. Since the southernmost of the proposed pits will be located 800 to 900 feet north of the property line, the entire reach through the pit areas will be characterized by aggrading and stable banks. These observations support the Division's determination that the river will not divert through the pits during a 700-year Flood. I & E Contact Address NAME: Aryol Brumley OPERATOR: Four States Arereeates LLC STREET: ~O Box 1568 CITY/STATE2IP: Cortez CO 8 7 921-1 568 cc Carl Mount, DMG Wallace Erickson, DMG John E. Akin Carol A. Stepe PO Box 596 Dolores, CO 81323 Marilyn Boynton 700 E. 2nd Street, #20 Cortez, CO 87321 ^ CE ^ BL ^ FS ^ HW ^ HMWMD (CH) ^ SE ^ WQCD (CH) ^ OTHER