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// PAGE 3 <br />EXHIBIT E <br /> <br /> <br />Raptor Materials, LLC Cogburn Sand, Gravel, and Reservoir Project February 2025 <br />A Regular Impact (112) Construction Permit Application – Colorado Division of Reclamation Mining and Safety, Office of Mined Land Reclamation <br /> <br />Figure 1. Typical Concurrent Lining and Regrade for Pit Depths below 30 ft <br /> <br />Lining of basins involves the placement of low permeability compactable fill, from on-site or other suitably <br />sourced geologic materials, into the keyway (dewatering trench); the same keyway used to facilitate <br />discharge to keep the basins dry and free of groundwaters at the time of extraction. The balance of the <br />basin floors (where needed) and slopes are also covered and compacted with the same materials until it <br />meets the standards established under the August 1999 State Engineer Guidelines for Lining Criteria. <br />Typical to obtaining approval for the constructed liner, the lined basin must pass a 90-day leak test. <br />Correspondence from the OSE approving the construction of the lined basin will be submitted to the OMLR <br />on receipt; or as part of any request for release of the permit, in part or whole. <br /> <br />Raptor has extensive experience successfully constructing lined storage reservoirs with several prior <br />projects completed, tested and approved by the OSE. The deposit contains extensive materials suitable for <br />use in constructing the liner including shale, claystone, clay, sandstone-claystone-siltstone and sandstone- <br />siltstone bedrock, clay lenses in the sand and gravel deposit, and overburden often comprised of low <br />plasticity sandy silty clay to silty sand. Excess topsoil has also been successfully used as a liner construction <br />material and could be used if excess material is available. Other materials encountered within the sand and <br />gravel deposit during excavation would be stored in temporary piles on the excavation floor. Parameters <br />such as plasticity, percentage of fines etc. have not been determined for the deposit materials at this time <br />but extensive experience in constructing several approved lined storage reservoirs with similar materials <br />along the Saint Vrain Creek and other rivers and streams provides high confidence in the availability of <br />suitable materials within the extraction area. <br /> <br />The liner will be progressively constructed once the pit is developed sufficiently to allow regrading and any <br />problems with the efficacy of the liner can usually be detected prior to leak testing through evidence of <br />seeps in the constructed liner which can have remedial action taken. Similarly, although not common, seeps <br />are sometimes observed in the bedrock floor. While these have generally in Raptor’s extensive experience <br />proved to be self-healing, where needed remedial action and spot lining and compaction would be <br />undertaken. <br />