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Depth of Pond The depth of water in the pond will be directly related to ground water fluctuations unless water quality is enhanced by other sources. Pond basins should be deep enough to provide year- round aquatic habitat. This is currently the case in Phase 1. This pond is deep enough in areas to prevent fish mortality from low dissolved oxygen and accumulation of metabolites during summer and winter stratification. Its habitat is enhanced by the continual flow through the pond of groundwater and runoff. Shallow water areas of less that two meters deep usually support emergent and subemergent aquatic plants that provide food and cover for fish and wildlife species. These shallow productive zones should make up 20 percent of the surface area of the pond. The existing pond is probably approaching that percent due to the shelving of the gravel deposits throughout the lake, especially at the north end, that prevented deeper maximum mining. It is recommended that some areas of the shoreline drop off rapidly to keep a portion of the shoreline free of vegetation for species requiring deeper, open water. Additionally, a good distribution of vegetation patches can be attained by creating an uneven and rolling bottom where shallow areas are mixed with deeper open water sites, we are under certain restrictions from the Colorado Division of Minerals and Geology as to shoreline slope into the water. We plan to create the mixed slope and uneven depths in places where possible at time of final reclamation and feel that some of these areas already exist. Shoreline Configuration and Slope In general, waterfowl require a greater ratio of land/water edge. An undulating shoreline, with points, coves, and bays provides more land or water edge. Islands can provide suitable nesting sites for ducks and geese than do the uplands adjacent to the pond as they are typically free of predators. We are committed to slope the edge of the ponds to at least a 2:1 (horizontal to vertical) slope above water and a 3:1 slope for 5-10' underwater. Although some animals will not use sites when the banks are too high, steep slopes do provide burrow sites for bank-nesting birds anc3 mammals such as belted kingfishers and swallows. We are committed to varying the slope within our safety and mining permit limits, undulating the shoreline where possible. We will create some 4:1 and 5:1 slopes, particularly at the north end of the existing pond. Pond Substrate and Structure Many aquatic organisms have specific substrate requirements for reproduction or cover. For example, crayfish either require material in which to dig burrows or need rocky areas with abundant spaces for shelter. A variety of sizes and bottom materials (from sand to large cobbles and small boulders) should 4