PERMFILE55264 - Laserfiche WebLink

Home Browse Search

significantly higher for grasses, fortis and total densities a[ [he .99 percent level and at the .95 percent level for shrubs on the non-mulched sites. Diversity, as measured by [he Shannon-Weiner Diversity Index, was 33 percent • ~,reater on the non-mulched sites. Using direct species counts, the non-mulched sites had 3.9 times more species present than sites planted to a gram mulch. In summary, these data document that the planting of an annual grain mulch hinders the development of perennial species present in [he topsoil. Continued use of an annual grain mulch under these conditions makes it difficult to achieve the regulatory goals of restoring species diversity. It has long been the assumption that the addition of a straw mulch to reclaimed sites is necessary due to the inability of those sites to produce a level of biomass necessary to stabilize the site. This supposition was tested by sampling and comparing biomass data collected on sites seeded to an annual grain mulch and areas supporting atutual weeds that volunteered from respread topsoil. Results from transects established adjacent to the proposed permit area by CYCC are presented in Table 57, Annual Grain Versus Volunteer Weed Biomass. The annual weed biomass growing on respread topsoil was equal to, if not greater than, the biomass produced from the planted annual grains. Statistically there was no difference in these values. Since the growth of annual weeds is a natural process of plant succession and produces a biomass equal to that produced by the planted annual grains without sacrificing the perennial plant species which volunteer from topsoil, TCC believes that it is desirable, from a revegetation standpoint, to seek a variance from the mulching requirement itt connection with this permit applicant. In support of a mulching variance, it is requested that CMLRD consider the ameliorative effect of chisel-plowing aitd contour furrowing on respread topsoil as described under Rule 2.05.4(2)(c), Reclamation Plan, Soil • Stabilization. The water detention capacity resulting from these surface manipulation techniques and the inherent infiltration potential of the soil, will allow all rainfall from a 10-year, 24-hour storm event to be potentially available fot' plant growth with no surface runoff expected from the reclaimed lands. Under Section 4.15.4(5) authority is granted to CMLRD to "suspend the requirement for mulch if [Ite pennittee can demonstrate that alternative procedures will achieve the requirements of 4.15, and do not cause or contribute to air or water pollution." If is the opinion of TCC that the present request contains sufficient documentation to demonstrate that pollution will be controlled and that the species diversity and woody plant density requirements of Section 4.15.8 would be best served by elimination of the mulching requirement on the Proposed TCC Underground Mine permit area. ~~~ ~ fi We r_ (, 7 Given these data and supporting literature collected at other sites, TCC requests that its proposed soil stabilization program involving chisel plowing, seeding of the proposed perennial mixture, and contour furrowing be accepted by CMLRD as an approved technique for reclaiming all lands disturbed as a result of mining activities. DETERMINING REVEGETATION SUCCESS Grazing Land reclaimed as pastureland may be grazed by livestock during the liability period in order to augment the livestock production capability of the adjacent ranch operation. If such grazing is conducted, a grazing management plan will be implemented which will include Flexible stocking rates and current livestock management practices to ensure the appropriate level of annual forage consumption. • The guidelines suggested by the SCS (197G) will be used [o formulate the proposed grazin, management program. Intensity and duration oFuse will be based upon growing conditions at the time grazing activities are initiated. MR 97-I ~-l 3.05-I 14 Rerised 9/9/97