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The approved postmining land use of the Hayden Gulch Mine is livestock grazing, rangeland, <br />and wildlife habitat. The Division approved minimum values that must be met for final (Phase <br />III) bond release for the following four vegetation success criteria: cover, productivity, species <br />diversity, and woody plant density. Those minimum values serve as success criteria for Phase II <br />release as well because they were set high enough to support the postmining land use. Phase III <br />release requires that statistically valid data be collected in the last two consecutive yeazs of the <br />liability period, rather than just a single year as required in a Phase II release. <br />Phase III Bond Release <br />Information in the SL-03 application demonstrated that the 8.9 acres of this bond release met <br />cover requirements. Both 2004 and 2005 data again indicate that cover has been achieved on a114 <br />(combined) pazcels. <br />In 2004 a mean of 2751.6 woody stems per acre was measured within the three shrub areas. In <br />2005 a mean of 1767 woody stems per acre was measured on the three shrub areas. The woody <br />plant density standard of 750 stems per acre was exceeded for both years of sampling. <br />The 2004 data shows 3 species with greater than 5% relative cover. These three species are <br />Bromopsis inermis (Smooth Brome) at 75.42% relative cover, Thinopyrum intermedium <br />(Intermediate wheatgrass) 10.77% relative cover, and Seriphidium tridentatum (MRCS Plants <br />database accepted name Artemesia tridentata, Big sagebrush) 8.08% relative cover. <br />The 2005 data shows 4 species with greater than 5% relative cover. These four species aze <br />Bromopsis inermis (Smooth Brome) with 62.45% relative cover, Thinopyrum intermedium <br />(Intermediate wheatgrass) 15.16% relative cover, Seriphidium tridentatum (Big sagebrush) <br />6.86% relative cover, and Eleocharis palustris (Common spikerush) at 3.97% relative cover. <br />Both the 2004 data and the 2005 data do not show that the shrub pazcels meet the diversity <br />standazd. However, the three shrub parcels were withdrawn from the SL-3 bond liability release <br />for the purposes of shrub enhancement. Diversity for the 355 acres disturbed at the mine site, <br />including these parcels, was demonstrated (this criteria met) in the SL-03 bond release. <br />As for productivity, this was not a isolated criteria for the retained small pazcels established for <br />shrub enhancement and stability. <br />Productivity for the four parcels met the criteria for Phase III bond release criteria under the SL- <br />03 bond release. <br />Hayden Gulch Mine Page 13 July 31, 2006 <br />SL-04 <br />