2016-12-05_REVISION - C1984065 (11)

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The operator originally proposed to disturb 104 acres of big sagebrush community, 113 acres of pinon-juniper woodland, 30 acres of irrigated hayland, and 9 acres of mountain shrub habitat during the life of the mine, but the extent of projected disturbance never occurred. At the time that operations ceased and final reclamation was initiated, approximately 45.2 (2000 Annual Reclamation Report) had been disturbed. Areas which originally supported sagebrush and mountain shrub vegetation are being restored to a dryland pasture/wildlife habitat postmining land use, and have been seeded with a diverse mix of adapted grasses, forbs, and shrubs. Irrigated hayland areas have been seeded with a mix of productive forage grasses and alfalfa, and the hayland areas will be irrigated with water from the Vulcan Ditch, which traverses the reclaimed area. Management during the liability period is to include proper management of livestock to promote the postmine land use, and control of noxious weeds. Weed control efforts were initiated in 1993, and will be continued annually as necessary to control infestations of Canada thistle, field bindweed, and Russian knapweed. Irrigation was initiated in the 1997 growing season, the operator has not irrigated the site in recent years, and due to the prohibitively high cost, no additional irrigation is anticipated. Quantitative sampling of revegetated areas was conducted in conjunction with a Phase II bond release, and will be accomplished in conjunction with final bond release during the final two years of the liability period. Phase II sampling of the dryland reclaimed areas was limited to vegetation cover, while Phase III sampling will include cover, production, and woody plant density. Phase II and Phase III sampling of the irrigated cropland will be limited to vegetation production. Statistically valid sampling techniques to be employed for demonstrations of revegetation success are described on pages 4-62a through 4-62c of the PAP. Sample adequacy demonstrations and statistical testing methods will be consistent with the Division's Bond Release Guidelines. Revegetation success standards are summarized below. Success standards are addressed in the PAP. Irrigated Hayland — 3000 pounds/acre. Sagebrush Community — Phase III vegetative success will be evaluated for cover, production and species diversity. Total perennial, non -noxious cover, as per Rule 4.15.8(3)(a), must be found to be greater than or equal to 90 percent of the reference area's total perennial, non - noxious cover with a 90 percent statistical confidence level. Additionally, herbaceous, perennial, non -noxious production, as per 4.15.8(4)(a), must be found to be greater than or equal to 90 percent of the reference area's herbaceous, perennial, non -noxious production with a 90 percent statistical confidence level. Species diversity success will be evaluated. Using relative cover for each species, the reclaimed areas will have at least four perennial species each with relative importance equal to or greater than 3%. No individual species which provides in excess of 60% relative cover Coal Ridge Mine Permit Renewal No. 7 18 December 5, 2016