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• 2.3 Determination of Current Annual Herbaceous Production <br />At each sample site, current annual herbaceous production was collected from a '/Z m2 quadrat <br />frame placed one meter and 90° to the right (clockwise) of the ground cover transact to fadlitate <br />avoidance of vegetation trampled by investigators during sample site location (see Fgure 1). Because of <br />observed field condifions, longer quadrats of 2 meters length (total of 1 rr~ were used in the reference <br />azea. Resutfing raw data were then divided by two to facilRate direct comparison with data from the <br />revegetated area. From within each quadrat, all above ground wrrent annual vegetation, with the <br />exception of woody species, within the vertical boundaries of the frame were clipped and bagged <br />separately by life form as follows: <br />Perennial Grass Perennial Forbs <br />Annual Grasses and Forbs Noxious Weeds <br />All production samples were returned to the lab for drying and weighing. Drying occurred at 105° C <br />until a stable weight was achieved (24 hours). Samples were then re-weighed to the nearest 0.1 gram. <br />Wet weights determined in the field were used to faalitate the collection of an adequate sample. <br />2.4 Sample Adequacy Determination and Testing for Strceess <br />Subsequent to development of the original bond release text within approved permit documents for <br />the North Thompson Creek Mines, the Colorado DMG promulgated new guidelines (April 18, 1995) that <br />offer new and possibly more statistically appropriate testing procedures for the determination of <br />revegetation success. Since these new testing procedures do not supersede (predate) those in the <br />approved permit, the Applignt reserves the option of selecting the statistical procedures to be utilized for <br />final testing. For purposes of this current evaluation, the Applicant has opted to use the new protocols <br />preferred by the State (One Sample -Reverse Null Hypothesis Testing). <br />When the redalmed area has entered the final two years of the responsitility period (2000 and <br />2001), mean cover and production values and assoaated variances will be determined for both the <br />herbaceous and shrub strata. These parameters will be determined using pant-intercept abng line- <br />trensects for ground cover and harvest methods for production from the revegetated community and the <br />extended reference area Sampling in these areas will continue until: 1) a minimum of 15 samples have <br />been collected and 2) sampling adequacy (nmr,J has been attained in accordance with the promulgated <br />2`S®~ Q7R~ Q~4168, [NC. Page 7 North Thompson Creek Mines Ptsise II !III Bon° Release EraluaNOn <br />