2020-12-09_REVISION - C1994082 (11)

Home Browse Search

In addition to seeding a mixture of grasses, forbs, and shrubs, on regraded areas where topsoil has been redistributed, selected areas received supplemental shrub seeding,planting, and transplanting. Species composition was generally consistent with the species reported in the application with relatively large quantities of forage grasses comprised of Elymus cinereus (Great basin wild rye),Agropyron smithii (western wheatgrass),Elymus trachycaulus (slender wheatgrass), forbes included Achillea millefolium (western yarrow),Medicago sativa (alfalfa),Linum lewisii (lewis flax), and woody plants included Artemisia alnifolia(silver sage) and Artemisia tridentata(big sagebrush),Rosa wodsii (woods rose). Numerous other desirable species were noted throughout the inspection consisting of a mix of forbs, grasses and shrubs. Noxious and invasive vegetation continue to be present at low levels in some areas requested for bond release under SL8. Weeds that have historically been of concern and continue to be the focus of control efforts on the Yoast Mine site include Cirsium arvense (Canada thistle), Cynoglossum officinale (houndstongue) considered an invasive species, and Cardaria draba(whitetop). The operator's weed management program has been successful in reducing densities of these species and minimizing expansions of weed populations. No noxious or invasive weed infestations or large patches of weeds were observed during the inspection. PHASE H As per Rule 3.03.1(1), 3.03.1(2)(a), and 3.03.1(2)(b), the applicant is requesting Phase II bond release on 193 acres that have achieved Phase I release with the approval of the SL2, 4, and 6 bond release applications. Topsoil Redistribution Topsoil was redistributed on regraded spoils within the release request area beginning in 2001 and ending in 2007. The required topsoil replacement depth at the Yoast Mine is an average of 1.8 feet(1.0 foot min.), on regraded mined areas, and 1.1 feet on reclaimed haul roads and facilities areas. For SU, SPL submitted results from 172 depth samples taken over 818 acres. The samples were evenly distributed throughout the reclaimed area. The results indicate that an average of 1.8 feet of topsoil had been replaced on the sample area. The Division finds that topsoil on the partial Phase II release areas has been replaced in accordance with the approved permit requirements. Revegetation Success Demonstration The approved revegetation plan is discussed in Tab 22 of the permit application package. Tab 22 describes the goals of reclamation,provides a revegetation plan and a description of how revegetation success will be demonstrated. The post mining land use approved for the site is for livestock grazing and wildlife habitat with a greater emphasis placed on livestock grazing. Attachment D of the SL8 bond release application includes a report and supporting documentation of how successful revegetation was measured. Attachment D was prepared by Cedar Creek Associates, Inc. ("CCAI"). The SL8 application discusses the livestock stocking rates and wildlife monitoring at the site,indicating that the reclaimed lands provide excellent habitat for wildlife and ample forage for livestock. SPL and CCAI largely refer to the SL8 bond release area as Bond Release Block No. 2a(BRB-2a), and BRB-3. BRB-2a comprising 123.7 acres, BRB-3 comprising 69.3 acres, and the appropriate reference areas were sampled and tested for the applicable revegetation success standards in 2016. The revegetation success standards for vegetation cover is based on a comparison of the monitoring results Permit Number C1994 082 Page 10 of 15