2014-08-27_GENERAL DOCUMENTS - C1982057

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• Modeling results (from SEDIMOT II and SEDCAD) showing very low levels of sediment loads from both the pre - mining and post - mining areas. Based on the information provided by SCC, it is the professional judgment of Division staff that sediment load quantities from the SL -05 areas would essentially be equal to the quantities of sediment loads from pre- mining conditions. Vegetation Establishment During the adequacy review of SL -5, the Division requested that a mesic drainage of Gulch 006 (PD -4) be removed from the bond release application. Mesic drainage vegetative success needs to be compared to pre- mining data of the Dry Creek drainage type. SCC had not provided this comparison, and had not sampled the mesic drainage type as a separate parcel. SCC removed the mesic drainage of Gulch 006 from the SL -5 application. The portion of Gulch 006 (4.7 acres) was removed from associated maps, and the requested bond release acreage adjusted to reflect exclusion of this drainage from the bond release request. The Southern expansion parcel 2005 -11 required additional maintenance. SCC conducted this work during 2013. As such, this 49.7 acre parcel was removed from the SL -5 application. During an inspection at the mine site on June 17, 2014, the Division found that drainage PM -4D to Pond 015, and the unnamed drainage east of culvert PM -10, had eroded significantly and required substantial repairs. Removal of a 4.2 acre 2002 reclamation parcel from the SL -5 application is necessary to allow for SCC repair to these two drainages. This same 2002 parcel containing PM -4D had previously been removed from SL4 application and has not been approved for Phase I Bond Release. The removal of this parcel from the bond release was discussed with, and agreed by, SCC staff in a telephone conversation on July 1, 2014. The total area that will be removed from the original SL -5 application totals 58.6 acres (49.7 + 4.7 +42 acres). SCC requests a revised Phase II bond release of 800.90 acres. The vegetation data was collected to adequacy. SCC collected 59 sample transects within the Bond Release Block. Sample adequacy calculations determined that a minimum of 25 samples were required. Removal of the excluded parcels data does not alter the adequacy calculations or the results significantly. SCC documented that success standards were still achieved with the excluded area data removed from the evaluation. SCC excluded noxious weed species from the reclamation success data. Only two noxious species were recorded in the sample data: Circium vulgare and Cynoglossum officinale. SCC excluded annual and biennial cover in excess of 10% relative cover, with the resulting adjusted cover value deemed "allowable cover ". The resulting cover standard is equal to 31.1% (90% of the extended reference area allowable cover value). 2009 allowable cover on the Bond Release Block was 45.93 %. The Division finds that the Bond Release Block exceeds the cover standard at the Seneca II -W mine. SCC was not required to Page 14 of 18