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It is also to be noted that the data from the two reference areas is weighted in accordance with the <br />original relative abundance of the types in the pre- mining landscape (83% mountain brush, 17% <br />sagebrush /snowberry). It was necessary to sample each to adequacy (see above) but in the process of <br />weighting, a reliable estimate of variance is lost. Thus the reference area standard is thereafter in the <br />process treated as a technical standard (i.e. without confidence limits) and one - sample t- testing is used. <br />HYPOTHESIS TESTING APPROACHES <br />For formal hypothesis testing relative to Phase III Bond Release the following procedures were followed: <br />Cover and Production <br />Phase III Revegetation success for cover and production will be demonstrated by one of following <br />statistically approved approaches. Although the CDMG 2010 proposed rules revisions are not finalized at <br />the time of this report, it is ESCO's understanding that they will be by the time the second year of <br />sampling is complete and the final report is written. Therefore, hypothesis testing of BRB -5 relative to <br />revegetation success standards includes approaches found within the CDMG 2010 proposed rules <br />revisions. <br />If sample adequacy has been achieved (minimum of 15 samples) in BRB -5 and the reference areas, and <br />the reclaimed area mean total allowable herbaceous cover and mean allowable herbaceous production <br />are above 90% of the reference area - derived standard, All criteria are met for a direct comparison and <br />revegetation would be deemed successful (CDMG 2010 proposed rules revisions 4.15.1 (2)(a)). <br />Were the mean allowable herbaceous cover and /or production of the reclaimed area above 90% of the <br />reference area - derived standard, and sample adequacy was met for the reference areas but not for BRB - <br />5 (minimum of 30 samples, technical standards not subject to sample adequacy), then the hypothesis of <br />reclamation success would be tested using a parametric test of the "reverse null" hypothesis. This would <br />be conducted using the following expression (CDMG 2010 proposed rules revisions, 4.15.11 (2)(c)): <br />x —Q <br />S_ <br />X <br />Where: x = Bond Release Block Sample Mean <br />Q = 90% of Standard <br />S_ = Standard error of mean [ s / V ] <br />X <br />S = Sample standard deviation <br />n = Sample size <br />tc = Calculated t value <br />6 <br />