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Soils - 10 - No topsoil was stockpiled prior to the existing disturbance at the P1cClane Canyon site. Future planned disturbances that will occur after permit issu- ance will be the sediment pond and topsoil storage area. Topsoil will be stripped from the area of the proposed sediment pond. Analyses indicated that these soils are good sources for topsoil for use in reclamation of the mine. The applicant proposes to strip the Nihill Loam soil to a depth of 12 inches and the Rivra Variant to a depth of 18 inches. This will yield a volume of 900 BCY of topsoil from the disturbed area. Part of this topsoil will be re- spread over one acre of the mine bench and the rest will be spread over the disturbed area of the sediment pond. These soils will be respread at a mini- mum depth of 4". A portion of the bench and outslopes along the reclaimed road will not be top- soiled. These areas consist of fill which was used for grading the road and original ground. The applicant has supplied a few analyses from grab samples of this material. Although these analyses indicated that the material is suitable for reclamation, it is insufficient for the determination.ef reclama- Lion feasibility. - The information provided with respect to the fill is too limited in depth and extent of sampling. The daterial will be mixed and rearranged during the re- grading process. For this. reason it Ss important that it be sufficiently demonstrated that any material which may be exposed during the regrading pro- cess is suitable for use as a plant growth medium and this stipulation is the . - preferred alternative to assure compliance. ' The applicant proposes to test the soil and add the appropriate fertilizers ;''~'- ' one year after seeding and planting. The applicant's justification for this - is that fertilization prior to seeding will encourage undesirable weedy spe- - cies to invade the reclaimed site. However, because phosphorous is relatively immobile and does not readily leach into the soil, it is best to incorporate it into the soil prior to seeding and consequently stipulated in the preferred alternative section. I The McClane Canyon site is located in an area that normally receives less than 10 inches of rainfall annually. This may be detrimental to revegetation. For this reason the surface manipulation of the soils is needed prior to seeding. Contour furrowing would protect the soil from erosion as well as enhance water holding capacity and availability to vegetation. Salt Creek Mining Company plans to rough the surface in areas to be broadcast seeded but intends to grade other areas. See required stipulation regarding this in preferred al- ternative, Ve~eta[Son The ;tunher Canyon project contains the same vegetation types and is located contiguously to the tlcClane Canyon site. Ablotic factors affecting the occur- .- rence of vegetation communities are similar. For [his reason, data from the two sites for productivity of the above communities were compared to determine if the conmunities of McClane and 'lunger Canyon were from differing popula-