2024-01-31_REVISION - M1977344 (19)

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Portland Limestone Quarries (M-1977-344) Permit Amendment-02 Holcim US Inc, 3500 Highway 120, Florence, CO 81226 Revised pursuant to preliminary adequacy review November 20, 2023 Phone (719) 288-1443 www.holcim.us 80 2.5 Exhibit E: Reclamation Plan (Rule 6.4.5) Post-mining land use will be rangeland, consistent with post-mining land use of BCQ. Rangeland will blend successfully with the vicinity land uses and post-mining land uses of the area mines. In addition, rangeland is suitable for the challenges of semi-arid high desert conditions of the area. Reclamation will improve available forage for cattle. This reclamation plan is in addition to the reclamation plans for BCQ and the Plant Area that were approved by the Division in the original BCQ application (M-1977-344) and AM-01. Due to the extensive life of RCQ, 100 years, Holcim intends to initially post bond for Sections 24 and 25 in Fremont County or approximately 30 years of quarry material. The bond will include reclamation for the conveyor and conveyor service road, quarry infrastructure and approximately 1000 acres of limestone and sandstone mining disturbance. The access road from the plant to RCQ and the Hwy 96 access road will not be reclaimed. At approximately year 20, Holcim will notify DRMS that a bond estimate for reclamation of anticipated disturbance in the subsequent 1000 acres will be forthcoming. Holcim will adjust the bond as appropriate in response to DRMS inspection, comments and recommendations. Bonding adjustments will continue in like manner for the life of the mine. All natural material above the translime geologic layer will be salvaged. Native plant growth material ranges in thickness from 0 inches where limestone outcrops to eight inches deep. The plant growth material will be segregated from the overburden and stockpiled along the perimeter in berms approximately 10 feet high and 100 feet inside the permit boundary. All overburden above the translime layer will be salvaged for use in construction of the perimeter berm and final reclamation. The perimeter berms will be seeded with a temporary seed mix to stabilize the surface. Stockpiling will continue until approximately Year 20 when contemporaneous reclamation will commence. Reclamation will occur contemporaneously with mining after Year 20 and continue in like manner through the life of the mine. At the end of mining, all reclamation will be completed within two years. Reclamation will include sloping benches, backfilling the sandstone pit and bringing up the elevation of the mine floor. An abundance of overburden exists to the extent that the lowest two benches will be completely backfilled thus raising the elevation of the mine floor . Two distinct reclamation efforts will be implemented to reclaim RCQ. The mined out area will be reclaimed beginning in Year 20 using stockpiled overburden and plant growth material using traditional equipment. At the end of the life of the mine, RCQ infrastructure including buildings, conveyor corridor and utilities will be demolished, and footprint reclaimed. Because of the 100-year life of the mine and ever-changing costs of reclamation tasks, Holcim suggests a phase bonding approach. Holcim proposes submitting a bond for the conveyor and access corridor, Sections 24 and 25 in Parcel 3, and the access to Hwy 96. This area will be developed and mined for 20 to 30 years. After Year 20, Holcim will review the bond to progress into Pueblo County sections for subsequent years. 2.5.1 Reclamation of Material Extraction Areas Reclamation of mined out sections of the mine will begin by rebuilding slopes using the salvaged overburden. A mined out area will be marked by up to 4 benches or 140 feet of highwall. Haul trucks will transport the stockpiled overburden to the toe of the benches. Bulldozers will push the overburden into the bench forming slopes 3H:1V or gentler (Figures 2.5.1-1). Excess overburden after rebuilding slopes will be used to elevate the pit floor. When the slopes are stable and the pit floor is at a suitable elevation, the area will be prepared for seeding. The rebuilt slopes and pit floor will be graded with a motor grader and compacted. The topsoil will