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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 peak <br />flow. During the spring runoff of 2003 peak flow was approximately 1,400 cubic feet per second. <br />Evidence of peak flow exceeding the bank full capacity of the channel was observed in areas upstream <br />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 area <br />are separated from the main channel by a historic flood protection dike. Permit documents indicate that <br />the flood protection dike was constructed by Ouray County during the 1950's to protect County Road 32 <br />and adjoining property from flooding of the Uncompahgre River. The operation is approved to breach a <br />portion of the dike and thereby divert portions of the river flow through the pit during high water. Flow <br />velocity through the pit area is reduced to encourage deposition of the excess bedload and to control <br />erosion. River flow is returned to the main channel through the downstream portions of the permit area. <br />After the high water season the operator restores the dike, returning all flow to the main channel. <br />Deposition of excess bedload within the side channel pit ensures a renewable resource and minimizes <br />impacts to the main channel. <br />Evidence of erosion was observed not only within the permit area but also upstream and downstream of <br />the permit area. The most significant erosion within the permit area and in areas adjacent to the permit <br />boundary appeared to be the removal of approximately 600 feet of the historic flood protection dike. The <br />dike had been constructed from alluvial cobbles and gravels piled approximately 6 feet tall with 1.5H:1 V <br />side slopes and 18 feet wide at the base. The eroded portion of the dike extended beyond the south <br />(upstream) permit boundary and approached Mr. Patterson's property. Near vertical cut banks were <br />observed at several locations, the greatest being 6 (+/-) feet high at the end of the eroded flood control <br />dike. The pit area, located adjacent to the dike, appeared to have been fully recharged with course <br />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 property, <br />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 of <br />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, approximately 10 <br />feet high, had resulted from this seasons peak flow. <br />Significant erosion was observed approximately 4 miles downstream of the ZMK permit, at the location of <br />the river restoration project being conducted by the town of Ridgway. Large boulders, approximately 1 <br />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 />seasonal deposition of excess bedload and by the constriction of the channel created by the flood <br />