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<br /> <br /> <br /> <br /> 23 <br />X. Backfilling and Grading <br /> <br /> The North Thompson Creek Mine has been backfilled, and graded, and fully reclaimed. <br />A discussion of the final reclamation is found in Section 4.4.2.3 of the permit <br />application package (PAP). The Division has previously approved Phase I and II bond <br />release on all regraded areas of the mine. <br /> <br />XI. Revegetation <br /> <br />Revegetation information is found in Section 4.4.2.3-Revegetation Plan of the permit, <br />inclusive of pages 4 -54 through 4-65. All disturbed areas of the Permit , other than <br />the permanent Developed Water Resources area and the area of four reclaimed water <br />monitoring flumes, have been reclaimed and Phase III Bond Release approved. <br /> <br /> The Division approved the inclusion of several introduced species in the seed mix. <br />These species include: Russian wildrye (Elymus junceus), Crested wheatgrass <br />(Agropyron cristatum), Cicer milkvetch (Astragalus cicer), and Orchardgrass (Dactylis <br />glomerata). None are considered poisonous or noxious. Four different seed mixes were <br />approved. Seed Mix No. 1 was developed for use on south-facing slopes and harsh <br />locations, like the dry, exposed Mancos Shale areas. Seed Mix No.2 utilized species <br />adapted for more mesic, cooler, and flatter sites. Seed Mix No.3 contained species for <br />use on the reclaimed refuse disposal area, mine area, and less harsh road cuts. The <br />fourth seed mix provided a quick effective cover for topsoil stockpiles. <br /> <br />The mine was reclaimed between 1986 and 1987 with final grading, seed preparation, <br />and seeding practices performed in the fall of 1987. Seed was planted using a drill <br />seeder in accessible areas with straw mulch crimped for stability . In locations <br />where steep slopes prohibited drill seeding, the appropriate seed mix was broadcast <br />and straw mulch applied and netted for stability. Woods rose (Rosa woodsii), <br />mountain mahogany (Cercocarpos montanus), and serviceberry (Amelanchier <br />alnifolia) were added to the seed mixes prior to planting. The operator committed to <br />live transplant additional shrubs if necessary, to achieve the required woody plant <br />densities. <br /> <br />In 1992, TR-12 was submitted to modify the reclamation success standards for the <br />majority of the loadout area due to an approved post-mining land use change to <br />residential/recreational. Reclamation success for the small remaining area at the <br />loadout was measured by comparing it to an extended reference area. <br /> <br />The revegetation success criteria for the reclaimed lands are: species diversity, <br />vegetative cover, herbaceous production, and woody plant density. Success was <br />determined by comparison with an undisturbed extended reference area. Baseline data <br />was not collected on the mine area prior to disturbance. The mine area was <br />disturbed prior to the enactment of the current law. In the original permit <br />application, a reference area was delineated in an undisturbed area which the <br />operator felt most closely approximated pre-mining conditions. Upon further analysis,