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Coulson Excavating Company, Inc. -Stroh Gravel Pit <br />Exhibit G-Water Information <br />The proposed pit is located on the northeastern border of the Big Thompson Watershed <br />Basin. The local tributary watercourse is the Big Thompson River, which runs <br />immediately north and east of the site. Several irrigation trenches run through and azound <br />the site, and an irrigation ditch (Hillsborough ditch) runs south of the proposed area. In <br />addition, a shallow unconfined aquifer occurs at the site and adjacent properties at <br />approximately 7 ft to 8 ft depth from the surface extending down to approximately 20 ft <br />to 25 ft below ground surface. The local groundwater flow direction is north. See Exhibit <br />C for the location of the river and ditches. <br />Hillsborough Ditch <br />The Hillsborough Ditch occurs at a distance greater than 200 ft from the permit area to <br />the south. Due to potential hydrologic effects to the ditch, a plan to monitor and replace <br />water flow in the ditch is as follows; <br />Monitor baseline flows <br />Baseline or pre-mining ditch flows will be determined by taking flow measurements, and <br />surveying in cross sectional areas at two locations shown in Figure 1 (approximately <br />1000 ft upstream and 1000 ft downstream of the proposed permit azea). Flow <br />measurements will be taken during times of average ditch flow to be determined by <br />communication with the ditch rider, Gary Bower. Flows will be calculated and ditch loss <br />will be calculated from the field data. <br />Monitor flows durine minine and replace water as needed <br />Flow measurements will be taken at the same locations and using the same methods as <br />described above. Measurements will be taken daily until the pit dewatering operation has <br />reached steady state (pumped down) and performed weekly thereafter. Ditch loss during <br />mine de-watering will be calculated and water will be returned to the ditch in the amount <br />calculated to be in excess of baseline ditch loss. A flow meter will be installed on one of <br />the dewatering pumps to measure replacement as needed. <br />Operational Water Loss <br />The operation is expected to affect the groundwater/surface water system by exposing a <br />small amount of groundwater to the atmosphere. The only other water loss from the <br />operation will be pore water taken with the mined product. <br />Water Quality Protection <br />Water pumped from de-watering trenches will be piped to asediment-settling pond <br />located at the northwest border of the project azea. Pump rates for the dewatering <br />trenches are expected to be approximately 0.15 - 0.72 MGD. The water will be allowed <br />