2021-10-13_GENERAL DOCUMENTS - C1980007 (2)

Home Browse Search

percent total live vegetation cover. This value is derived from the mean of the total vegetation cover values from the 1996, 1997, 1998, and 2010 quantitative data obtained from the historic records vegetation community sampling. Reclaimed areas will be considered successfully reclaimed to the final revegetation success criterion if the total vegetation cover on the reclaimed area is not less than 90 percent of the total vegetation cover value of 53.04 percent, with 90 percent statistical confidence using a one-tailed "t"test. The woody plant density standard has been waived at the West Elk Mine. The approved postmining land use for the parcels described in Table I is Rangeland and Wildlife Habitat; accordingly the revegetation objective is to achieve a self—sustaining vegetative cover of hardy grasses, forbs and shrubs that will become a productive and ecologically stable biotic community which will support the grazing of livestock and provide a suitable habitat for wildlife. III. OBSERVATIONS AND FINDINGS PHASE II The parcels described in Table 1 were reclaimed between 2010 and 2015. Topsoil was distributed on the parcels in Table 1 immediately after the disturbance had been backfilled and graded. As discussed in Section II of these Findings,there is no minimum topsoil depth requirement for the parcels in Table 1. It was verified through visual inspection that all stockpiled topsoil had been distributed across the reclaimed area. Seeding of the parcels in Table I took place soon after topsoil had been spread,typically between September and November of the year in which the parcel was reclaimed. Sampling to assess vegetative cover and to support a sedimentology evaluation was completed between June 19 and July 1, 2019,by Cedar Creek Associates,Inc. The sampling methodology was approved by the Division before the sampling took place. Sample locations were laid out using a hybrid protocol, where a random(x, y)coordinate was used to establish the datum of a systematic grid. 10-meter transects were initiated at the grid vertices in a pre-determined random orientation. A I-meter bar, emitting laser beams at I0-centimeter intervals,was placed at 1-meter intervals along each transect. The ground cover at each point of intercept of the laser beam was recorded,giving a total of 100 ground cover measurements per transect. Each transect represented a single sample. The parcels included in the SL-13 application were sampled as a single block. According to the vegetation sampling report,40 samples were taken,which satisfied sample adequacy. Total live vegetation cover of 55.68%was reported; a value which includes several noxious weed species:Bromus tectorum, Cheatgrass(0.18%); Cirsium arvense, Canada Thistle(0.53%); and Cynoglossum ofcinale, Houndstongue(0.23%). Noxious weed cover was 0.93% in total, (relative cover of 1.66%). Non- noxious weed vegetative cover was 54.75% in total, (relative cover of 98.34%). The data show that vegetative cover exceeds the revegetation success criterion of 47.74% (that is, 90% of 53.04%). The vegetation community is progressing toward one that will support the postmining land use. The sampling data show good species diversity,dominated by perennial grasses and forbs, and a low relative C-1980-007 Page 7 of 11