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Replacement of Topsoil Replacement of topsoil maybe considered an element of Phase II work. This mining operation was active before and at the time of issuance ofthe initial permit. There was insufficient salvaged topsoil to cover the entire site. No topsoil was reportedly available for the No. 1 or No. 3 Mine portal areas. Available soils were analyzed for suitability as plant growth media and found to be suitable with the addition of certain amendments. Cover An extended reference area is used to compaze reclaimed mine azeas to undisturbed native communities at the North Thompson Creek Mines. For vegetative cover, the revegetated area shall be considered acceptable if it is not less than 90 percent ofthe cover as deterrined from the reference azea. Vegetation cover on the reference area was measured in 2000 as 30.1%. Vegetation cover on the reference azea was measured in 2001 as 30.4%. Thus, the cover standazd for revegetated areas was 27.1 % in 2000, and 27.4% in 2001. AVF Agricultural Productivity The loadout conveyor corridor traversed 1.2 acres of meadow [grazed Roazing Fork River alluvial valley floor (AVF)]. This AVF meadow was grazed by domestic livestock and was thus unavailable for non-grazed productivity sampling. Due to the small area (1.2 acres) ofthe grazed AVF meadow, and the unavailability of non-grazed meadow as a reference azea, the Division and the operator agreed that the extended reference area productivity would be applied as the compazison standazd for the 1.2-acre reclaimed AVF area. Herbaceous production on the reference area was 13.6 grams/0.5 squaze meter in 2000. Application ofthe 90% reference azea criterion results in a production standard on the small segment of-AVF o€12.2 grams-per-half squaremeter in-2000: Herbaceous production ofthe - reference azea was 8.7 grams/0.5 MZ. in 2001. Thus the 2001 production standazd on the AVF was 7.8 grams per half square meter. Contribution of Suspended Solids Reclamation success was to be determined indirectly by a compazison of reclaimed ground soils and vegetative cover with adjacent nonrnined areas (the extended reference area). All functions of the equation used for comparison are, except for the cover parameter, constant. Thus a criterion for contribution of suspended solids is met if ground cover is better over reclaimed azeas than the reference area. This criteria applies to the areas of permanent structures for Phase II bond release. Restoration of Hydrologic Function The restoration ofthe essential hydrologic function ofthe AVF is a requirement For Phase II SL-O5, C-81-025, March 24, 2003 Page 10 of 26 Pages