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Golden Wonder Mine DRMS Mine Permit No M-1978-091 Storm Water Management Plan sump on the Leve16 pad, maintenance of the road run-on channel etc.), therefore the first portion of the season will be dedicated to monitoring the effectiveness ofthese controls. If in the event these controls need enhancement, additional structures (described in the following subsections) may be placed. A summary of the proposed management practices to address the Level 6 access road concerns as well as the Level 6 waste rock concerns include: Leve16 Access Road Setting: The portion of the Level 6 access road within the mine permitted area and falls within stormwater permit boundaries is approximately 0.25 miles along a steeply sloped hillside. As such, the road provides a stormwater path of travel for overland flows from the above hillside. These flows have sought a low point where erosive materials have been cut through to create a stormwater channel at the bottom of the road, just prior to entering the Leve16 pad. It appears that the combined flows over the distance of the road have created Yhis cut over the past several years (reported in Site Inspection reports since 1996). Au Mining has maintained arun-on channel on the road which routes stormwater to a sump on the Leve16 pad. This run-on channel and sump are maintained as a routine process. If these features are unable to control flows, then additional management practices may include; The flows from the existing run-on channels will be routed to stormwater culverts placed at equal distances along the length of the road. The actual locations are dependent upon suitable construction areas. • The flows routed through the culverts will be released to the hillside on the downhill side of the road, and carried through riprap baffles comprised of large cobble to boulder-sized materials. These baffles will dissipate flow energy and allow for sediment settling. They will also disperse flows into the natural hillside for easier absorption. The actual placement of the baffles is dependent upon the down-slope suitability/stability. • All flows from the access road length will have been circumvented by means of the above combination of features, meaning that the flows will not reach the Leve16 pad itself. Leve16 Waste Rock Pile Setting: The Level 6 waste rock pile is pad on which outside mine operations occur. It is less than 0.5 acres in size and currently retains several stormwater management practices including pad slope and contouring which routes pad stormwater towards the hillside base and not over the pad edge, berms along the perimeter of the pad confine water from precipitation to the pad footprint, a stormwater infiltration basin is located on the pad to