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Topsoiling <br />All topsoil was redistributed at this site. No topsoil stockpiles remain. Distribution <br />of topsoil over the regraded areas improves the chances for revegetation success over <br />the bond liability period and reduces the likelihood of erosion problems developing. <br />Areas of exposed spoil and overburden materials were not observed during the final <br />field inspection, indicating all areas received at least a minimal application of topsoil <br />prior to reseeding. No significant rills or gullies exist on the reclaimed areas. <br />Revegetation <br />The original pre-mine community at the Trinidad Basin Mine (TBM) site was <br />pinyon juniper. According to limited sampling of the site, the pre-mine community <br />consisted of 3.3% absolute cover of perennial grasses, 0.7% cryptograms, 14.0% <br />shrubs and 35.3% trees. TBM proposed to return the site to rangeland comprised <br />primarily of grasses. <br />Stipulation numbers 7-12 in the original permit findings addressed deficiencies with <br />the baseline vegetation information, the revegetation plan and methods for <br />determining reclamation success. According to the permit system, these stipulations <br />were complied with, although the documentation regarding the reclamation success <br />standards is minimal. A reference area was sampled; however a map showing the <br />location could not be located. A letter proposing revegetation success standards was <br />received by the Division on February 18, 1992. <br />The standards proposed on February 18, 1992 are based on a range site description <br />suggested by the US Soil Conservation Service. Using the SCS information, TBM <br />proposed the following revegetation standard: <br />Total absolute areal cover: 32.0% <br />Relative vegetation cover: Grasses 45-60% <br />Forbs 35-40% <br />Shrubs 1-5% <br />Productivity 400 pounds (air dry) per acre <br />No correspondence acknowledging whether or not the standards were accepted was <br />located. <br />Revegetation Sampling Success Methods <br />Revegetation data was collected on the reclaimed areas on June 25-26, 2007 and <br />June 23-24, 2008. The sampling methodology was the same in both years. <br />Data was collected in the field for vegetative cover and herbaceous production by the <br />14