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Cross Gold Mine <br />December 2024 E-7 <br /> <br /> <br />and subgrade together where there is access and safety is not compromised. The seedbed will be <br />loosened (four to six inches (4" to 6") deep) and smoothed. <br />GIR will replace topsoil in as even a manner as equipment and terrain allows. Topsoil will be sourced <br />locally in Nederland, CO (approximately 5,750 CY.). Because of the shallow, cobbly and rocky soil <br />types at this site, there is no available site soil for reclamation. Soil amendments will be as <br />recommended by the local NRCS. Currently, they recommend that if soil tests are not performed, forty <br />(40) pounds per acre of each of the major nutrients (nitrogen and phosphoric acid [H3PO4]) be applied. <br />If phosphoric acid is applied, it will be applied on the overburden prior to plant growth medium <br />replacement. This nutrient is not mobile. Placing it in the root zone prior to plant growth medium <br />replacement will ensure optimal utilization by plant roots. <br />Soils having been compacted by traffic or other equipment will be tilled (approximately 0.7387 acres) <br />(deep-chiseled or ripped if necessary) breaking up restrictive or compacted layers, and then harrowed <br />and rolled or packed to produce the required firm seedbed. Seed will be broadcast seeded. The <br />seedbed will be settled and firm but left rough enough to catch the seed and allow some coverage by <br />soil when tracked in by equipment or harrowed and packed into the soil surface. Seedbed preparation <br />will be avoided when the soil is wet to prevent seedbed compaction. <br />Topsoil will be replaced to a depth of 8 to 12 inches in area with thin and rocky soils (approximately <br />0.178 acres [Costs in Appendix L-1 reflect soil to 12 inches.]). Soil will need to be deep enough to <br />encourage root growth. Other areas (WRL footprint for instance) topsoil will be placed to a depth of 2 <br />feet (approximately 1.25 acres). <br />Because this is an underground mine, no overburden was removed, and none will be replaced. The <br />operation will not conduct backfill operations as one would expect for open pit or strip mine. There is <br />always the possibility some minor backfilling may occur (ponds). Where backfilling should occur, it will <br />be done in such a manner that the backfilled material will be appropriately compacted to prevent <br />slippage or settling, provided it can be done in a manner that does not endanger operators and <br />equipment. No toxic or acid forming material will be backfilled on site. Therefore, leaching of toxic or <br />acid forming materials shall not occur. No topsoiling of revegetation will be conducted at the Comstock <br />Area outside of that need at the Caribou 300 Level portal itself. <br />Table E-3. Topsoil Replacement Requirements <br />Portion of Site Area (acres) Topsoil Thickness (inches) Topsoil Quantity (CY) <br />Stockpile Yard 3.1 8 3335 <br />Tailings Storage Facility 1.9 8 2299 <br />Total 5.0 5,634 <br />The following seed and planting mixes were developed based on vegetation descriptions found in <br />Exhibit J, recommendations from the Colorado Division of Reclamation, Mining, and Safety (DRMS), <br />and research by O’Shea-Stone and Ash (2008). Actual seed and planting selections may be adjusted <br />depending on availability at the time of reclamation or if site conditions change. <br />The primary goal of revegetation is to restore meadow-like conditions, rather than to fully replace all trees <br />and shrubs. For this purpose, the DRMS Inactive Mine Lands Program recommends a specific high-