2012-02-27_REVISION - C1981010 (10)

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1.2 Documentation of Successful Vegetation Establishment Trapper Mine reclaimed rangelands in Flintlock and East Flintlock (Z) pits, as outlined on Map 1, were sampled during 2010 to determine the success of vegetation establishment. Canopy cover, shrub stem density and plant composition were the parameters sampled. The purpose of the sampling was to evaluate the readiness of reclaimed parcels /blocks for Phase II bond release. 1.2.1 Methods Vegetation transects were systematically located on the Trapper Mine rangeland block evaluated for Phase II bond release during 2010, as outlined on Map 2. A grid system utilizing 400 -foot vertical and horizontal spacing was overlaid on 1"=400' topography maps to establish systematic transect locations. Transect starting points were field located using a G.I.S. satellite survey system in combination with large - scale topographic maps. Transects were 50 meters in length and run in a random direction from the starting point. All transects were kept within reclaimed parcel boundaries. If the randomly selected transect direction resulted in the possibility of the transect line crossing a parcel boundary, the transect line was turned 180 degrees to avoid crossing the boundary. Plant canopy cover and plant species composition were estimated by using the point -hit technique (Optical Point Bar). Each 50 -meter line transect was monitored at each site with 10 observations recorded along each line transect at 5 -meter intervals (total 100 contacts /transect). Woody stem density was calculated using belt transects. All woody stems located within one meter of either side of the 50 -meter transect line were counted and tallied by shrub species. Transect data were designed to be summarized by individual transects and by reclaimed land "parcels" and "blocks." Parcels were delineated on the basis of: 1) reclaimed pit area, 2) initial year of seeding and 3) range site. Blocks consist of a logical grouping of parcels lumped together for bond release evaluation purposes. Plant cover sample adequacy (i.e. number of transects required) was determined by block for Phase II bond release criteria using equations specified by the Colorado Division of Reclamation, Mining and Safety (CDRMS). 1.2.2 Results and Discussion Postmine ground cover and woody stem density data for all reclaimed rangelands sampled are summarized by reclaimed block and compared against Trapper's bond release technical standards (Table 1.2 -1). Tables 1.2 -2 and 1.2 -3 summarize reclaimed block ground cover and woody stem density, respectively, by life form and by plant species. A complete list of plant species encountered on reclaimed