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Page 14 <br /> 6.4.4 EXHIBIT D — Extraction Plan <br /> The later creation of farm to market County Road 396 eased access to the <br /> areas' agricultural fields, yet consequentially separates the fields at the TRP <br /> with its graveled surface, and subsequent rights-of-way and easements. <br /> The levees, public roads, cottonwood corridors and area tributaries are visible <br /> in the different map exhibit aerial images, and will not be impacted by planned <br /> extraction. All planned operations have conforming setbacks, and levee access <br /> will remain limited to wheeled vehicles during operations. <br /> Today, the upper terrace where extraction operations are planned, supports <br /> agricultural crops above the lower stream terrace formed further below and <br /> beyond the perimeter levees and cottonwood corridors that frame the adjacent <br /> active stream channels. The Fields designated for resource recovery (Central <br /> Field and North-West Field; as shown on Exhibit C - 2: Extraction Plan Map) lie <br /> over a nearly level upper terrace of the two rivers. The South Platte <br /> River borders the southern and eastern extent of planned extraction, and the <br /> Big Thompson River intersects the permit area north of the Fields. <br /> The stream terrace itself is a riparian area that supports on its flanking <br /> escarpment an uneven aged stand of Cottonwood trees. The uneven aged <br /> trees suggest this segment of the river has experienced some scouring in the <br /> past from periodic, yet commonly limited, flooding; which encourages natural <br /> regeneration of Cottonwoods. <br /> To determine the influence of past activities on groundwater, twelve (12) <br /> Piezometer Wells were located along and within the entire TRP boundary. <br /> Groundwater level information here, is based on 5.75 years of continuous <br /> monthly measurements at twelve (12) piezometer locations identified on the <br /> included Exhibit G: Water Information Map. Recorded groundwater depths <br /> vary in elevation below the surface, with a general (weighted) mean depth of <br /> 8.40± feet. <br /> Groundwater elevations are influenced by crop irrigation practices that run <br /> generally from April through September, and may occasionally lag into the <br /> middle of October. During this time groundwater depths may be skewed <br /> higher in elevation to the extreme North-eastern extents of Central Field, yet <br /> with few exceptions, groundwater elevations over the entire site remain <br /> significantly deeper than 5.11± feet from the surface, year over year, over the <br /> entire TRP area. <br /> Using the approximate surface elevation at the extreme eastern boundaries of <br /> North-West Field and Central Field, and noting that groundwater fluctuations <br /> will commonly meet at 8.40± feet below the surface, yet rarely rise more than <br /> 5.11± feet from the surface, we determined the Static Water Level using the <br /> VARRA COMPANIES, INC. TWO RIVERS SAND GRAVEL AND RESERVOIR PROJECT MARCH 2O22 <br /> A REGULAR IMPACT[1121 CONSTRUCTION PERMIT APPLICATION-COLORADO DIVISION OF RECLAMATION MINING&SAFETY <br /> OFFICE OF MINED LAND RECLAMATION <br /> l <br />