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Wattenberg Lakes Amendment, Exhibit E—Reclamation Plan May 2023 EXHIBIT E - RECLAMATION PLAN 1.0 GENERAL Area 1 and Area 2 will be mined and reclaimed as part of the development of Pond 1 (Struck Pond)that the landowner, the City of Westminster,will own and use for water storage. Pond 3, previously reclaimed through construction of the slurry wall,will also be used by the City of Westminster for water storage; please see Technical Revision JR) 1 for slurry wall technical specifications and construction completion report(12/18/2014), approved by DMRS (1/8/2015). Other un-reclaimed but previously mined areas within the permit boundary will also be reclaimed through backfilling, as needed, and minor grading, and establishment of plantings and ground covers to restore and enhance all areas disturbed by current or previous mining activities. The primary changes in the current DRMS permit amendment reclamation plan compared with the 2004 DRMS permit reclamation plan include the following (changes to the mining plan are noted in Exhibit D): • Pond 1, now called the Struck Pond, has an expanded footprint to the west of the originally planned pond in the area previously identified for wetland mitigation area and slightly north as well; this adjustment to the north results in an addition to the affected area covered under the 2004 permit, thus requiring this amendment. • Pond 2, identified in 2004 in the west-northwest part of the permit area, now is planned for wetland mitigation with part of the area to remain dedicated for access to two remaining producing oil wells. • The Pond 3 boundary along the west side was straightened during mining and a slurry wall was constructed around the revised pond perimeter. • Some of the previously identified wetland mitigation areas are changed in location to accommodate revised plans for future use of the site. • The wetland planting list is updated based on recent information including a wetland survey. Key considerations for preparing this reclamation plan include the following: • All wetlands on the site were located and delineated in June and August 2022. Existing wetlands will be avoided to the extent feasible during mining, earthmoving, and reclamation activities.Also,wetlands will be created in the identified wetland mitigation areas. • Maintenance activities on the site will also include a comprehensive Weed Management Plan to limit the spread of invasive species into the riparian areas and wetlands. • The Pond 1 (Struck Pond) reservoir will be isolated from the surrounding alluvial aquifer by constructing a slurry wall; a perimeter drain will also be constructed to minimize impacts of the slurry wall on groundwater flow through this area. • Multiple groundwater monitoring wells are located within the permit area and will continue to be monitored before, during, and after the mining and reclamation are completed. The wells will be used to monitor effects from mining and provide information for mitigation of potential impacts on groundwater levels and riparian vegetation, as necessary. See Exhibit G for more information. 2.0 RECLAMATION OVERVIEW As discussed in the Mining Plan (Exhibit D), Holcim anticipates conducting operations under this DRMS permit amendment in three phases for a total duration of 18 months,with mining of Area 1 and Area 2 planned for only 2 months of that duration (in Phase 1 only). The reclamation activities in these three phases will occur concurrently (for Phase 1)or within nine months after completion of Phase 1 (for Phases 2 and 3). Reclamation will focus on constructing the pond liner/slurry wall and also general backfilling and earthwork leading up to planting and seeding to establish vegetation in the disturbed areas. Reclamation, including regrading and seeding, will be completed within 2 to 5 years following initiation of these remaining reclamation activities. The three phases are: 1. Phase 1 —Concurrent activities (10 months) a. Grade/fill to achieve side slopes of 3:1 OTETRA TECH P a g e 1 1 6