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road at the former location of weigh scales just north of Tunnel Drive. The sediment pond will be constructed to contain a minimum of one acre foot of storm water and will include: a contingency design for handling storm flows in excess of the 100 year event, which may overfill the retention pond. An approved spillway device will be included that will allow for low velocity release of stormwater from sediment pond #4 to the Tunnel Drive area should this situation ever occur. The goal of this Stormwater Management Plan is to result in a acro ~irc.harge of stormwaters to the Tunnel Drive area up to a maximum 100 year event. Sediment pond # 1, located at the western edge of the mining zone, will intercept all storm flows entering the mining zone from the undisturbed watershed west of the mining area. #1 sediment pond will be configured in an elongate shape minimally twice as long as it is wide, 100' long by 50' wide, and will include a bentonite or other water impermeable liner to minimize loss of stormwater to percolation through the sediment ponds walls and/or floor. A spillway will be located at the opposite end of the sediment pond's inlet which will be designed for ul~ to 200 cfs of flow. The spillway device will deliver storm Flows into a storm ditch excavated into granite bedrock which will flow in a northerly direction at 1-2% grade and will intercept all storm flows from the mining zone as well as storm flows from the undisturbed watershed above and west entering the mining zone. The storm ditch profile may vary, as shown in the attached drawings, to facilitate mobile mining equipment movement across the site. The stone ditch will convey al stormwaters to the north to the SWMP area noted on the attached maps. Sediment pond(s) #5 area is actually a series of elongate sediment and stormwater containment structures connected by inlets and spillways designed to handle maximum stormwater velocities and volumes as projected by the Sed-Cad and STORM program results utilized in the surface hydrological study The thirty acre addition to the affected land acreage is specifically for the containment and management of storm flows formally flowing to the Tunnel Drive area and does not contain minable reserves nor will be mined for construction materials in the future. The sediment pond/retention pond structures in the north SWMP area will be constructed from course alluvium materials currently in place on site and will be built to minimize disturbance to the area. That is, the construction will take place in narrow bands of disturbed alluvium necessary to construct the berms, outslopes, and basins of the elongate sediment ponds oridVtted in a north- south direction. The juniper-pinon cover will be retained as much as possible over thy; SWMP area. By increasing the flow paUt distance and decreasing storm flow velocities, it is intended to promote percolation of storm flows into the course alluvium materials underlying tltc area and result in no overland flow to neighboring areas to the east of the SWMP area., No negative impacts are anticipated to lands bordering the SWMP area to the east. The land currently bordering the SWMP acreage to the east is Tezak Heavy Equipment Co, Inc. Property. Colorado State land administered by the Pueblo Community College is located east o1'this area between Tezak Heavy Equipment Co. Property and Sand Gulch, the main N-S drains€;e paralleling US Highway 50. PCC has been notified in detail as to the SWMP plan and has not responded to date. All disturbed areas within the SWMP acreage will be reclaimed via establishment of native grasses, Forbes, and shrubs, as noted in the species list included in the original amendment application package. Tree species such as pinon and juniper and shrubs such Mm mahogany and four-wing saltbush may be included in the direct seeding of the b~