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WATER INFORMATION EXHIBIT G <br /> 1. Surface Water General Discussion <br /> Pre-mine surface water features at the Ralston Quarry consist of ephemeral ditches on the east <br /> side of the property,the Denver Water ditch that passes through the water tunnel to Upper Long <br /> Lake Reservoir, and a pair of sediment ponds southeast of the processing area. Mining will only <br /> affect the ephemeral ditches on the east side of the site, which will be removed. The remaining <br /> features will be either completely unaffected(Denver Water ditch and water tunnel)or reclaimed <br /> after mining is complete (sediment ponds). The post mine condition will see a net reduction in <br /> the runoff leaving the site. Map C-2 shows the drainage basins, drainage patterns, and surface <br /> water control improvements for the site. Map F-1 shows the post mine drainage patterns. <br /> 2018 Slide Area <br /> —i Disturbance associated with the 2018 slide will be regraded,topsoiled, and revegetated as soon <br /> as possible following approval of this amendment. This area drains to the Denver Water Ralston <br /> Reservoir. Map C-4 shows the drainage areas that are affected by activity related to the slide, and <br /> the surface water runoff systems to be used to prevent sediment discharge. <br /> 2. Hydrology and Sediment Control for Mining <br /> The only water that will be found within the disturbed area is stormwater runoff and water <br /> 21 transported to the mining area and used in processing and for dust control. <br /> Uphill Runoff <br /> 2.2 Due to the topography of the site, most uphill areas are on the ridge upon which mining is taking <br /> place. There are no outside areas that drain onto the operation area. <br /> Disturbed Area Runoff <br /> Disturbed area on site consists of four drainage basins: <br /> 1. North platform above water tunnel: drains to quarry during mining <br /> 2. Quarry south of water tunnel: drains into itself(pit bottom) <br /> 3. Processing and storage area in the southwest corner of the site: drains to the sediment <br /> ponds to its southeast. <br /> Ralston Quarry CrM 1. icki and Ax ialc%PIA A' <br /> January 2019 G-1 <br />