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EXHIBIT G WATER INFORMATION <br /> 1. General <br /> Pre-mining current conditions of the site include dry rangeland and native grass vegetation, a <br /> high mesa top, and lower valley areas including the now dry Bradford Reservoir. The disturbed <br /> areas of the site are approximately 1 mile south of the Bradford Canal and approximately 1 mile <br /> east of the Homestead Canal. Associated canals connecting the above mentioned waterways are <br /> further than 0.75 miles from the disturbed areas of the site. The closest major water of the U.S. is <br /> the Huerfano River, 3.75 miles to the northwest of the site. The site is well outside of FEMA <br /> identified floodplains. <br /> Surface water flows will be limited and surface waters are expected to infiltrate prior to <br /> accumulating and leaving the site. Surface water flows to the west and southwest and are <br /> temporarily captured in a sump located in the western area of the processing area. Nine foot tall, <br /> 3H:1 V sloped, and seeded overburden berms surrounding the sump ensure that no surface flows <br /> may exit the disturbed areas of the site. <br /> Due to the coarse soil textures found at the sight, permeability is moderate and most precipitation <br /> and runoff percolates quickly into the ground. Surface water that does not reach the sump will <br /> infiltrate into the underlying fractured Pierre shale and porous sand and gravel overburden and <br /> will occur within 72 hours. Surface flows that do not occur within the active mining area will be <br /> diverted around the disturbed area via two foot tall berms and/or small ditches. No sediment will <br /> be allowed to leave the site and cloud any downstream waters. <br /> NRCS Custom Soil Resource Report details Group D soils for the area of the Bradford Mesa <br /> Quarry site that will drain to the western sump. The runoff coefficient for Group D soils that <br /> cover open space with grass cover<50% is 0.89. The runoff coefficient for disturbed dump soils <br /> with <50% grass cover is approximately 0.75. The storage volume to prevent discharge is <br /> calculated as the volume of the drainage area above the water table. The water table lies greater <br /> than 100 feet below the surrounding surface. Processing area and dump acreage was calculated <br /> using a scaled map image from 2016 in AutoCAD software, see Map C-2 in Appendix B. <br /> Bradford Mesa Quarry <br /> August 2019 G-1 <br />