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EXHIBIT D <br /> MINING PLAN <br /> Kiewit plans to operate a sand and gravel mine on Section 36 Township 11 North Range 67 West, <br /> encompassing an area of roughly 640 acres and designated by Kiewit as the Carr Pit given its proximity to <br /> the town of Carr, Colorado. The mine will consist of a total of 13 cells as outlined in the mine phasing plan <br /> attached as Sheet C-1. The property is bifurcated by Lone Tree Creek. A 300' buffer on each side of the <br /> Lone Tree Creek is required and planned for as part of the plan to mine the property. A buffer around the <br /> existing cultural resources are also included in the mining plan. The intent is to leave the cultural resources <br /> in place and provide an appropriate buffer around them; the recommended buffers are also shown on the <br /> mine plan on Sheet C-1. <br /> For this site Kiewit plans to incorporate a pit mining approach,which is a common type of open excavation <br /> for sand and gravel. This type of pit tends to be shallow and generally have limited surface extent. Pit <br /> Mining produces relatively little waste because unmarketable overburden or other materials may be <br /> bypassed during mining or returned to the pit after processing.Headwalls of the pit will be mined at a slope <br /> of 1:1. <br /> During the underground soil exploration of the property by Terracon completed in March of 2020 (and <br /> attached for reference as Appendix A), it was observed that the property on the west side of Lone Tree <br /> Creek had an average of 1.9' thick layer of topsoil overburden that was underlain with a significate sand <br /> and gravel deposit to approximately 10' to 15' below the surface grade(BSG). Below that sand and gravel <br /> layer from 10-15' BSG to the total depth of excavation white grey sand was found. Ground water varied in <br /> depth from 16.5' to 24' BSG. The intent is to mine this property dry and not excavate into the ground water <br /> table. The deepest sand and gravel layer found during exploration was 12.5' which will be the maximum <br /> depth of the mine; therefore, the pit bottom will be at least 4' above the witnessed ground water elevation. <br /> It is anticipated that the ground water could fluctuate seasonally but not to a degree that would result in the <br /> water table rising to the pit bottom.However,if during mining operations ground water is encountered then <br /> it will be backfilled to at least 2' above that elevation; a depth of 2' above ground water will be maintained <br /> in all areas of the mine. <br /> The material that Kiewit is interested in mining is the sand and gravel that begins at 1' to 2' BSG and <br /> extends to the layer of sand at 10` to 12.5' BSG. This material would be screened and sorted according to <br /> size. The sand and squeegee will be separated and stockpiled for use in Kiewit's hot mix asphalt plants <br /> along the Front Range. The larger diameter rock will be sorted and crushed to produce '/2" and 3/4" gravel <br /> for use in Kiewit's hot mix plants along the Front Range. <br /> The process used in mining this material will be as follows. The topsoil from cell 1 will be removed and <br /> stockpiled in order to expose the sand and gravel layer. Sorting, crushing, stockpiling, loading and all <br /> processing equipment will be set up on cell 3. The sand and gravel will be sorted, crushed, and stockpiled. <br /> The sand below the primary mining layer may not be financially feasible to mine; if it is mined it will be <br /> excavated only to a depth of at least 2' above the ground water level. Further evaluation will be conducted <br /> to determine if this sand is of value. Upon completion of the mining of the useable sand and gravel from <br /> cell 1, cell 2 will be stripped of its topsoil. The topsoil that is stripped off the new cell will be placed in the <br /> previous cell to reclaim the cell. Further details of reclamation will be outlined in Exhibit E. This process <br /> will be repeated throughout the property until the sand and gravel is exhausted or it becomes finically <br /> unfeasible to mine this property. <br /> As shown on Sheet C-1,the west side of the site will be accessed near the southwest corner of the property, <br /> with material hauled one of two directions: <br /> Kiewit <br /> DRMS 112 Permit Application <br /> Page D-1 <br />