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In the bond release application Flatiron Companies affirmed the SEDCAD <br />assumptions made in the permit application for the alternative sediment control <br />system. In calculating the soil loss from the reclaimed areas, a cover factor of 60% <br />was originally used. The 1998 vegetation cover data showed that the cover factor is <br />79% for the reclaimed area. This increased cover factor further reduces the <br />predicted sediment yield predictions off the reclaimed area. <br />Summary and Conclusions <br />Based upon a review of the mine permit, the applicant's bond release application, <br />and site inspections, the Division finds that Flatiron Companies has replaced topsoil <br />in accordance with the approved reclamation plan. The Division finds that the <br />reclaimed area subject to this bond release is not contributing suspended solids to <br />streamflow or runoff outside the permit area in excess of premining levels or in <br />excess of adjacent nonmined areas. <br />B. PHASE III <br />Reveeetation <br />'The revegetation plan at the Bourg Mine was designed to reestablish the pre- <br />mining land uses of rangeland and wildlife habitat. During the initial permitting <br />of the Bourg Mine, the Colorado Division of Wildlife (DOW) was very concerned <br />about the Denmark lek, a sage grouse strutting ground adjacent to the mine. This <br />was the largest strutting ground in North Park, and possibly the whole state. <br />DOW was concerned about the loss of sagebrush and potential impacts to the <br />grouse habitat. Therefore, the DOW strongly recommended that sagebrush and <br />other native grass and forb species be planted on the reclaimed lands to mitigate <br />the impacts of mining. Flatiron Companies agreed to this and planted a high <br />percentage of sagebrush and predominantly native grass and forb species. The <br />seedmix is presented in Table 4 (c) of the permit application. <br />Revegetation success standards for the Bourg Mine are found in Volume L of the <br />permit application starting on page F-10. The standazds are to be achieved during <br />the last two years of the liability period. Pre-determined standards were set for <br />shrub density and species diversity. The shrub density standard was set at 2,000 <br />stems/acre. The species diversity standard was based on undisturbed area data. <br />Two reference areas were established in a grassland community and sage shrubland <br />community to serve as the success standard for vegetative cover and productivity in <br />the reclaimed areas. The permit application on page F-l 1 says, "the data from the <br />reclaimed areas will be compazed to weighted averages of the cover and <br />productivity data from the reference aeeas. The sagebrush reference area will <br />receive 75% and the grassland reference area will receive 25% (75/2 weighted <br />standard). These figures correspond to the pre-mining acreage of each vegetation <br />type" The cover and productivity standard was set at 90% of the weighted means <br />from the reference aeeas. <br />Bourg Mine 5 Final Bond Release <br />Permit No. C-81-021 January 18, 2000 <br />