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Trapper's approved postmining land use is rangeland. Three different rangeland veeetative communities are designated on reclaimed areas of the Trapper Mine; these are called A, B, and C. The bond release parcels in this bond release request are only rangeland A and B. The vegetative cover success standard for rangeland A is 52 percent, with a[ leas[ 33 percent herbaceous cover and no more than 19 percent litter. For rangeland B, the cover standard is also 52 percent, but herbaceous cover has to be at least 29 percent while litter cannot exceed 23 percent. (For rangeland C, the cover standard is 47 percent; the herbaceous cover must be at least 25 percent and the litter cannot be greater than 22 percent.) When counting the plants in the field which comprise cover, the Division's bond release Guideline prohibits counting any noxious weeds. Also any annual or biennial species which comprise more than 10% of the total cover should not be included in the count (page 7 of the Division's bond release Guideline). Trapper's bond release submittal addresses revegetation success with revegetation data that Trapper has collected. Sediment Yield Limitation The amount of bond that can be released in a Phase II release is limited by Section 3.03.1(3)(b) if the released lands are contributing excessive sediment to adjacent lands. The limitation is: " No more than sixty (60) percent of the bond shall be released so long as the lands to which the release would be applicable are contributing suspended solids to streamflow or runoff outside the permit area in excess of premining levels as determined by baseline data or in excess of levels determined on adjacent nonmined areas". Trapper addresses this requirement by including in the bond release submittal a computation (using the SEDCAD 4 computer program) of the amount of sediment that the released lands yield before and after mining as a result of a 101-year, 24-hour precipitation event. The submittal also contains a comparison of pre-mining versus post-mining soil loss predicted by the Universal Soil Loss Equation. Special Conditions Section 3.03.1(2)(b) of the Regulations imposes special conditions on a Phase II release if mining operations have impaired the use of prime farmland or an alluvial valley floor. Those special conditions do not apply in Trapper's bond release request because there is no prime farmland or alluvial valley floor affected by the bond release parcels. In addition, Trapper's postmining rangeland use exempts the bond release from the special conditions required by Section 3.03.1(3)(e) for a Phase II release which involves industrial, commercial or residential postmining land uses. Topsoil Replacement Thickness The Division's bond release Guideline/calls for verification of replaced topsoil thicknesses in a _~ Phase II bond release evaluation. Trapper s approved reclamation plan specifies that topsoil is to be replaced to a minimum thickness of 12 inches on rangeland sites A, B and C. (There is no Trapper Mine Phase II Bond Release Page 4 12/21/99