2022-09-26_PERMIT FILE - M2022042 (5)

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Windsor East Mine, Exhibit E – Reclamation Plan September 2022 Page 2 | 4 Martin Marietta will concurrently mine and reclaim this site. Reclamation, including regrading and seeding, will be completed within two to five years following the completion of mining or filling operations for each phase. The mining and reclamation will leave no high walls on the property. No acid forming or toxic materials will be used or encountered in the mining. There will be no auger holes, adits, or shafts. 3.0 RECLAMATION MEASURES – MATERIAL HANDLING Site reclamation measures are illustrated in Exhibit F. Reclamation of the site will include 2 water storage ponds (54.7 acres) and 95.6 acres of upland vegetation. The ponds will be reclaimed as water storage ponds. All mine walls will be re-graded with overburden material to create a compacted liner. Slopes above the post-mine high water level will be 3:1 and slopes below the post-mine high water level will not exceed 3:1. Topsoil will be spread to a minimum depth of 6” over the surface of all areas outside the water storage basins that are to be revegetated as uplands. Scrapers will be used to place the backfilled material. Using scrapers to layer the lifts at a maximum 3:1 slope ensures a stable configuration. Reclamation quantities and costs are summarized in Exhibit L. 4.0 WATER Overburden and mine materials will be inert and impacts to local surface water or groundwater quality are not anticipated to occur because of mining activities. Martin Marietta Materials, Inc. will comply with all applicable Colorado water laws and all applicable Federal and State water quality laws and regulations and appropriate storm water management and erosion control to protect the adjacent Cache la Poudre River and riparian vegetation. Cell B will be backfilled above the water table leaving a 5-foot depression as defined in our lease. No stormwater will be directed to this depression, but any stormwater collected will dissipate into the ground. GWIP, LLC, the landowner, intends to use this depression as part of their stormwater detention when they develop on adjacent land and will work with Town of Windsor on their development once our reclamation permit is released. Martin Marietta is not required to install any structures as part of the depression including but not limited to headwalls, outlets, piping and forebays. 5.0 WILDLIFE Presently, the area is used for general agriculture. There is significant habitat for many wildlife species along the river corridor which is outside our permit boundary. Please see Exhibit H (Wildlife Information) for more information pertaining to the recommendations and conclusions from the environmental report. 6.0 TOPSOILING Topsoils in the proposed mine areas are predominantly Aquoll and Aquents, Ellicott, Colombo clay loam, Kim loam, and Nunn clay loam. All suitable soil material will be salvaged for topsoil replacement. Topsoil will be replaced, where required, in reclaimed areas at a depth of a minimum of 6 inches. The topsoil will be segregated and stored separately from the overburden material as required by Rule 3.1.9(1). Sufficient topsoil will be stockpiled within each phase to reclaim all disturbed areas. The mine plan map depicts the location and configuration of the berms. The berms will be protected from wind and water erosion by vegetative cover if in place for more than 180 days and will be vegetated depending on the seeding “window” parameters for dryland grass, which are typically between September and April. Soil amendments are not expected to be required due to the nature of the soils. However, topsoil samples will be subjected to agricultural testing prior to reclamation to assess fertilizer requirements. The Soil Conservation