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Mr. Humphries - 2 - February 9, 1987 Also in a letter from Wayne Sowards (Utah International, Inc. March 19, 1982) to Mike Savage (MLRD) the statement was made in reference to the Appendix E paper "Reestablishment of Shrubs at the Trapper Mine" that "Although we did not precisely define success standards for shrubs; it seems logical to judge success based on the size of the changes, the distance between them, and % survival of the transplanted shrubs within the changes." In summary, in the Division's opinion there is at this time no clearly established shrub density standard. Item 2) Is the Division's standard of 1,000 stems per acre technically justifiable at Trapper Mine and consistent with the approved post-mining land use? There are several issues involved here, each issue will be discussed individually as follows: a. Is the proposed standard of 1,000 stems/acre excessive because it would eliminate the rangeland element of the land use? Trapper Mining, utilizing an SCS canopy cover of shrubs formula from SCS Colorado Range Note, No. 27, 1987 (is this date a typo?), and an estimated average shrub crown diameter of 5 feet, concluded that with a stem density of 1,000 stems per acre the canopy cover would be 45%. Rather than utilizing a formula and estimated canopy diameters, MLRD has calculated the actual diameters of shrubs on each range site in its current condition, which is probably similar to what, over many years, the reclaimed site will return. These diameters were calculated from pre-mine shrub densities (Table 2.3-9 of the permit application) and shrubby cover (Table 2.3-13 of the permit application). Actual average canopy diameters on the pre-mined areas are 0.26 feet on Range Site A, 0.17 feet on Range Site B and 0.28 feet on Range Site C, or approximately 0.215 feet on Range Sites A and B averaged. With these diameters, the average canopy cover at 1,000 stems/acre would be 1.55%, which certainly would not provide a hindrance to the use of the areas for grazing, although this percent shrub cover would be very minimal for winter wildlife use. b. According to USSCS, Standard and Specifications-Brush Management, 1984, shrubs should be thinned when canopy cover exceeds 10 to 15% dependent on shrub species. However, this publication defines brush as species which are not part of the natural (climax) plant cortmunity or that occur in amounts significantly in excess of that natural to the site. This is not the case at the Trapper Mine. Also as previously discussed Range Sites A and B will not exceed 10 to 15% canopy cover.