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with rip-rap armoring as proposed. The "catchpoint" areas along both sides of the proposed roadway define the area influencing the drainage ditch which wit{ carry storm runof7'from the roadway and neighboring upslope areas along the length of the road from the highest (west) end to the influence of the culvert crossing the road easement approximately at mid-point of the easement length. The ditches along both sides of the access road will be typical "V" shaped ditches two feet deep and three feet wide at top cut directly in the cobble stone and gravel material at the site. The coursely sized gravels and cobble will act as adequate Iininl; for the ditch itself with no addition of rip-rap or liner necessary. The ditch will be monitored for any potential erosion or gullying development and rip-rap up to 1 foot in diamater will bc: placed in any areas of ditch showing potential problem areas. Directly below the 30" culvert, a detention pond of approximate volume of 58,750 cubic feet (1.34 acre-feet) will be constructed to detain stormflows from the upper one half of the access road as shown on the accompianin€; map titled "PROPOSED ACCESS ROAD FROM TUNNEL DRIVE". The sediment pond will be constructed from on site, course gravel and cobble that outcrops at this location. The: former river cobblestone material will allow for rapid percolation of stormwater flows into additional cobblestone and gravel materials which underlie the Canon City property directly do~Hrrslope from the sediment pond. The flow path from culvert including the bottom of the sediment pond will be lined with rip-rap up to 1' diameter, 2 feet deep for water energy dissipation. The inlet to the culvert on the upstream size will be lined with rip-rap in a similiar manner. The size of sediment pond was based on the following criteria: The size of the watershed along the upper half of access road right-of--way is limited to the road and the area directly above the upper half of the roadway to the city's water treatment plant, app. 8 acres of potential watershed. Due to the diversion of stormflows from mining area and watersheds above, stormflow potentials were estimated utilizing a 8.2 acre watershed with an average slope of 10% and flowpath of 600 feet. The watershed surface is a ancient course river gravel with numerous cactii species growing over the area. High percolation rates and topographic control (A former ditch right of-way crosses the slope above the road construction, intersecting all potential downslope flews) results in storm event estimations for ten years, twenty-five year, and one hundred year events to total, .5 acre feet of discharge into the detention pond, .85 acre feet of stormwater into the detention pond, and 1. l acre feet of stormwater discharge into the detention pond, respectively. The is no spillway planned for the sediment pond. The outslope and disturbed areas will be revegetated with native grass, forbe, and shrub seeding and mulched as per described in the reclamation details of the permit application. In the extreme event that stormflows should ever breach the detention basin, stormflows will cross over Canon City property and flow into the concrete storm drainage channel currently in use which crosses Tunnel Drive and drains into the hydraulic ditch. The mine operator has engineered the size of the detention pond to contain and disperse stormflows with no overflow of the pond or drainage into the hydraulic ditch up to and exceeding one hundred year storm events. The lower half of the proposed access road will drain along the existing path of the City of Canon City's unpaved road to the water treatment plant. The ditches along both sides; of the access road will be constructed as the upper half, a "V" shaped cross section ditch 2 feet deep and three feet across at the top of the ditch cut directly in the course gravels outcropp~ ng at this 2