2010-08-30_REVISION - C1981008 (3)

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Irrigated Pasture cover in the reclaimed area is 115.8% of the 90% mean reference area in 2007 and 128.7% of the 90% mean reference area in 2008. This demonstrates the successful achievement of the post-mining land use of Irrigated Pasture in the areas in question by generating successful cover and production of the desired species. Additionally, the strong presence of meadow brome, alfalfa, and orchard grass (an average of 75% of the species found) in the revegetation shows that the Irrigated Pasture area will be quality for livestock foraging. Dryland Pasture cover in the reclaimed area is 132.7% of the 90% mean reference area in 2008. The 2007 Dryland Pasture cover adequacy was demonstrated using a one-sample "standard null" t-test (see 1310-Logic report). This demonstrates the successful achievement of the post-mining land use of Dryland Pasture in the areas in questions by generating successful cover and production of the desired species. Please see the attached December 12, 2008 (Revised in July 2010) 1310-Logic reported, titled: 2007-2008 Vegetation Studies for Phase 3 Bond Release, First and Second Year Analysis, Irrigated Pasture and Dryland Pasture, page 15 & 16. As demonstrated in the 1310-Logic report, the Dryland Pasture cover has a t,, of 0.938. The 1- tailed t table value (tt) has a value of 1.323. The null hypothesis is accepted, and revegetation in the reclaimed Dryland Pasture area is deemed successful. 2. Structures Left No structures are left in place on any of the areas covered by this release application. The post-mine land use is irrigated and dryland pasture. 3. Topsoil Thickness Topsoil was replaced to the thicknesses shown by the sample points on Map R-2, in accordance with the mine permit. This was also addressed in the Phase 2 bond release from 2008. 4. Final Topography and Drainage Patterns The final topography of the original site has been restored to approximate original contour within the reclaimed areas. The enclosed Map R-2 shows this topography. The reclaimed areas all drain to the south to Calamity Draw. Some of the surface draining off of Area 3 will drain to Pond 007 before passing into Calamity Draw. 5. Surface and Ground Water The potential surface and ground water impacts from the New Horizon #2 Mine were detailed in Section 2.05.6(3) of the permit, under the Probable Hydrologic Consequences section. The main potential impact is the possible infiltration of water into the replaced overburden leading to the degradation of pyrite, and the subsequent effect this can have on the dissolved solids and pH of the water. 0 SL-12 DRAFT 20AUG10.wPd 37