Laserfiche WebLink
detailed and comprehensive, several issues of concern were raised during the adequacy <br />review. <br />The Division questioned what field characteristics would be used to define appropriate <br />salvage depths and requested justification for complete or partial salvage variances <br />proposed for a number of soil map units. SCC provided appropriate detail in regard to <br />field salvage depth determinations. Generally, in shale derived soils dominated by <br />western wheatgrass /alkali sagebrush vegetation, a 6 inch depth was salvaged. In <br />sandstone derived soils dominated by mixed brush vegetation, salvage was terminated at <br />the sandstone bedrock contact or when a characteristic reddish brown clay subsoil was <br />encountered. <br />In response to the salvage variance concerns, various tables, exhibits and text sections <br />were revised to indicate that all suitable topsoil would be salvaged and that no salvage <br />variances were being requested. The proposed soil replacement depth was changed from <br />1.1 feet to 1.3 feet. Based on disturbed area modifications, updated soil balance <br />calculations, and reclamation plan changes made in association with PR -5, the approved <br />average replacement thickness in the original permit area is 1.3 feet, and average <br />replacement thickness in the South Extension area is 1.1 feet. Within designated aspen <br />planting exclosures, approved average replacement soil thickness is 4.0 feet; within <br />upland shrub establishment areas topsoiled in 2006, average replacement thickness is 0.6 <br />feet. <br />Certain statements in Tab 21 indicate that topsoil in map units 101, 103 and S 103 may be <br />of questionable suitability based on rock fragment content. Current information indicates <br />that topsoil in the subject map units is suitable and was salvaged. <br />Soil stabilization methods proposed by the operator consist primarily of minimal seed bed <br />preparation (resulting in a roughened soils surface) and use of either straw mulch or a <br />quick growing annual grain cover crop on all topsoiled areas. Reclaimed areas will be <br />inspected annually by the operator as required by the proposed rill and gully maintenance <br />plan, and additional stabilization measures will be implemented if results of the annual <br />evaluation warrant such modifications. Graded spoils with excessive clay content as <br />detected by monitoring described in Section III.E, above, were deep ripped to relieve <br />compaction, pursuant to 4.06.4(1). <br />A topsoil amendment program will be initiated if visual observation or annual vegetation <br />monitoring indicates symptoms of nutrient deficiency within reclaimed vegetation stands. <br />Generally, native species are adapted to the fertility levels of the replaced topsoils, and <br />fertilization has not been shown to be of significant long term benefit in the region. <br />SCC may prepare a roughened seedbed on slopes steeper than 25 % to be employed in <br />conjunction with broadcast seeding. The roughened seedbed entailed extensive gouging <br />Seneca II -W Findings Document 43 C- 1982 -057 <br />Permit Revision No. 6 January 6, 2012 <br />