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Page 4 <br />Section 3.03.1 <br />demonstrations, the applicant has used the RUSLE equation, this time on each <br />separate reclamation parcel independently. Table 4 of the application provides the <br />RUSLE parameter input and the estimated values for the pre-mining and post-mining <br />condition. <br />The Division agrees with the fixed value for the R factor as 19 for both the pre-mining <br />and post-mining condition on all reclamation parcels. <br />The Division agrees with the pre-mining values of the K factor based on the weighted <br />average of soils within each parcel and the weighted average value of .24 for the post- <br />mining condition, derived from the weighted average of all parcels. <br />The Division generally agrees with the variation of the LS factor for the pre and post- <br />mining condition, with the following comments. While the Division understands that <br />post-mining topography may from the pre-mining topography, overall the site after <br />reclamation will generally have an equal amount of steep slope areas in the post-mining <br />condition as were present in the pre-mining condition. The premise would also be true <br />for moderate and gentle slopes as well. Parcel by parcel, there are noted, significant <br />differences in the LS factors. However, the total of the pre-mining LS factors used is <br />166.45, compared to a total of the post-mining LS factors of 184.66. This would indicate <br />that site-wide, post-mining slope and grades are similar to the pre-mining condition. <br />The Division does not agree with the C factors used for either the pre-mining or the <br />post-mining condition. The applicant ignores the Phase II vegetation data when <br />selecting pre-mining C factors on a parcel by parcel basis. Instead, they apparently use <br />somewhat arbitrary information based on the pre-mining vegetation community. It is not <br />valid to compare a reclamation parcel sampled for total cover in 2006-2009 to pre- <br />mining information collected decades prior to the Phase II sampling. The applicant <br />should select the C factor on a parcel by parcel basis using the pre-mining vegetation <br />community to develop a weighted average of Mountain Shrub versus Sagebrush, then <br />use the 2006-2009 reference area vegetation data, specifically vegetation and litter <br />cover, to calculate a C factor. Using the reference area data fairly compares the <br />seasonal climatic conditions and growth of the reference area with the seasonal growth <br />of the actual reclaimed area. Both were subjected to approximately the same climatic <br />conditions as since the comparison is an estimate of the "annual" amount of soil loss, it <br />is only fair to compare using data accurately reflecting the annual variations. It is noted <br />that each of the applicant's four years of sampling data included both reference area <br />sampling and reclaimed area sampling. <br />The applicant used a uniform, site-wide C factor of .010 for the post-mining condition. <br />Again, this is not appropriate, as the C factor can be readily and accurately estimated <br />using the Phase II vegetation sampling data from the individual parcels. The Division <br />notes that applicant used specific information for each parcel for the K factor and the LS <br />factor.