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(Page 3) <br />MINE ID # OR PROSPECTING ID # M-1991-146 <br />INSPECTION DATE 6/13/03 INSPECTOR'S INITIALS WHE <br />General Inspection Topics <br />DMG last inspected the site on April 30, 2003, prior to spring runoff, and reported no problems or <br />possible violations. The June 13, 2003 inspection occurred towards the end of spring runoff, after <br />peak flow. During the spring runoff of 2003 peak flow was approximately 1,400 cubic feet per <br />second. Evidence of peak flow exceeding the bank full capacity of the channel was observed in <br />areas upstream of the permit area. Flow debris littered the channel. <br />Mine identification sign was posted near the mine entrance. Permit boundary markers were posted. <br />Mining activities appeared to have been confined to permit areas. The excavation and processing <br />area are separated from the main channel by a historic flood protection dike. Permit documents <br />indicate that the flood protection dike was constructed by Ouray County during the 1950's to protect <br />County Road 32 and adjoining property from flooding of the Uncompahgre River. The operation is <br />approved.to breach a portion of the dike and thereby divert portions of the river flow through the pit <br />during high water. Flow velocity through the pit area is reduced to encourage deposition of the <br />excess bedload and to control erosion. River flow is returned to the main channel through the <br />downstream portions of the permit area. After the high water season the operator restores the dike, <br />returning all flow to the main channel. Deposition of excess bedload within the side channel pit <br />ensures a renewable resource and minimizes impacts to the main channel. <br />Evidence of erosion was observed not only within the permit area but also upstream and downstream <br />of the permit area. The most significant erosion within the permit area and in areas adjacent to the <br />permit boundary appeared to be the removal of approximately 600 feet of the historic flood protection <br />dike. The dike had been constructed from alluvial cobbles and gravels piled approximately 6 feet tall <br />with 1.5H:1V side slopes and 18 feet wide at the base. The eroded portion of the dike extended <br />beyond the south (upstream) permit boundary and approached Mr. Patterson's property. Near <br />vertical cut banks were observed at several locations, the greatest being 6 (+/-) feet high at the end <br />of the eroded flood control dike. The pit area, located adjacent to the dike, appeared to have been <br />fully recharged with course sediments, as anticipated by the approved mine plan. <br />Evidence of recent erosion to a flood protection dike, similar to the eroded dike within the ZMK <br />property, was located approximately 1 mile upstream from the ZMK property. <br />Significant erosion was observed approximately 3 miles downstream from the ZMK permit, in a reach <br />of river also modified prior to the DMG permit. At this location pre-permit modification to the channel <br />included removal of meanders and constriction of flood flows. Near vertical cut banks, <br />approximately 10 feet high, had resulted from this seasons peak flow. <br />Significant erosion was observed approximately 4 miles downstream of the ZMK permit, at the <br />location of the river restoration project being conducted by the town of Ridgway. Large boulders, <br />approximately 1 cubic yard in size, had been displaced by this seasons peak flow. <br />Conclusion <br />A complete inspection of the ZMK Pit was conducted in response to the complaint submitted by Mr. <br />Patterson. As noted above, the stability of the river channel at this location appears low, by virtue of <br />