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<br />,~ ~ <br />New Horizon Mina: 2(H3T Vegatafrorr Sampling for Phase 3 Bored Release <br />1.4 PUl2P©SE <br />Western Fusis Colorado, LLC (iIUFC}seeks Phase 3 bond release on portions of the New <br />Horizon Mine {NH-2} reclaimed coat mine lands near Nuda, Colorado {see Figure 3); under the <br />terms of a permit issued by the Slats of Colorado, Division of Reclamation, Mining, and Safety <br />(CDRMS). The reclaimed lands consist of lands with a designated post-mine Land use of <br />Dryland Pasture, Irrigated Pasture, and Irrigated Swats {Irrigated Pasture and Irrigated Swats <br />were combined for purposes of vegetation sampling and are considered together as "Irrigated <br />Pasture" in this report}. For Phase 3 bond release, WFC must demonstrate to CDMMS that <br />vegetation on the reclaimed lands meets standards far cover and production in 2 out of 3 <br />consecutive years beginning na earlier than year 9 after reclamation activities are completed. <br />Summer 2007 was the first year of Phase 3 measurement eligibility far the Lands described in <br />this report. in .tune 2007, t31Q-Logic Environmental (Bfp-Logic} measured cover and production <br />an NH-2 reclaimed lands and nearby reference areas, in support of Phase 3 bond release. This <br />report presents the sampling results and an analysis of the vegetation da#a for purposes of <br />demonstrating adequacy of revegetation far Phase 3 bond release. <br />DafinJfians <br />Cover. CDRMS regulations allow cover to be defined'as either canopy or basal cover of living <br />herbaceous or herbaceous and woody vegetation. For this study we use canopy cover of living <br />herbaceous and woody vegetation. For cover measurements on redaimed lands. CDRMS <br />regulations allow the inclusion of annual grasses and (orbs up to 10°~ of total cover, and cover <br />of annuals aver f 0% of total cover is allowed up to the amount of total cover of annuals <br />measured at the reference area. <br />Prodactton. CDRMS regulations define production (on pasture, rangeland, and for forage <br />crops such as hay} as current year above-ground biomass of herbacsous vegetation. <br />StandaM. CDRMS regulations for Phase 3 bond release and the NH-2 permit specify the <br />standard for cover and production as the mean value far the reference area. Revegetation is <br />considered "successful" for the parameter in question 'rf the mean value for the reclaimed area is <br />demonstrated to squat or exceed "t2" (Q~OQIa of the standarcf)> at the !30% confidence Level. <br />Comparison of Measured Parameters. The following summarizes CDRMS regulations and <br />guidance on comparing vegetation measurements at redairned lands to standards for purposes <br />of determining adequacy far Phase 3 bond reisass. {rec} =reclaimed area, (ref) =reference <br />area. Minimum sample size of n =15 is required at each site. <br />1. If mean (rec) equals or exceeds Q, and 'rf sample adequacy exists at (rec} and {ref}, then <br />revegeta#ion is successful. If mean (rec) is less #han Q, then statistical hypothesis <br />testing is required, as fellows. <br />2. t€ sample adequacy exists at (rec) and (ref), use aone-sample "standard nult" #-test. A <br />one-sampis test assumes that the reference arsa mean is a "standard" rather than a <br />sample mean, and doss not require an evaluation of the variance of the reference arsa <br />mean or other statistical complications inherent intwo-sample tests. ,The null hypothesis <br />bring tested is that the mean (rec) is equal to or greater than Q. If the null hypothesis is <br />NOT rejected, revegetatian is successful. <br />@ID-Gogh Environmental <br />November 12, 2U07 <br />Attachment 1-4 <br />