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Table 5 New Horizon North Mine <br />Baseline Study Area - Reference Area Statistical Comparison <br />Dryland Pasture Baseline (2009) vs. Old Peabody <br />Sage Reference Area (2014) <br />Reference Area <br />Baseline <br />Comparable/ <br />Incomparable <br />Perennial Cover <br />Estimated Mean (% cover) <br />25.15 <br />16.67 <br />Sample Variance <br />Sample Size Collected <br />Pooled Variance <br />Cakulated t-statistk (t*) <br />15.71 <br />20 <br />182.95 <br />15 <br />Incomparable, <br />Reference Area <br />Higher <br />86.66 <br />86.66 <br />2.6679 <br />Tabular Value for t(o.95,n,+n2-2) <br />2.0345 <br />Production (Herbaceous Perennial) <br />Estimated Mean (g/0.25m2) <br />7.90 <br />9.78 <br />Sample Variance <br />18.93 <br />68.68 <br />Sample Size Collected <br />Pooled Variance <br />40 <br />50 <br />Comparable <br />46.63 <br />46.63 <br />Cakulated t-stat&tk (t*) <br />1.3030 <br />Tabular Value for t(0.95,.1 +n2-2) <br />1.9873 <br />While the statistical testing of the Dryland Pasture Baseline (2009) and the Old Peabody Sage <br />Reference Area did not yield a comparable result, the reference area is still an appropriate option. Rule <br />4.15.8 (2) states that vegetative cover and production must be at least equal to the pre -mining <br />conditions (through use of a reference area comparison). Therefore, using a reference area which <br />exceeds the vegetative cover and production of the pre -mining conditions for comparison meets the <br />intent of the rule, by reclaiming to a higher or better use (4.16.1 (2)). <br />Any reference area selected for comparison (whether statistically comparable or not) must adhere to <br />rules and be achievable. The Old Peabody Sage Reference Area represents higher success criteria than <br />required by the rules. However, New Horizon firmly believes these success criteria are achievable for the <br />following reasons: <br />• Baseline data collected in 2009 included degraded land (particularly north of Meehan Draw). <br />These degraded areas were subject to overgrazing and encroachment of prairie dogs which lead <br />to diminished cover values observed in 2009 surveys. New Horizon will use proper land <br />management practices during the liability period to ensure that reclamation meets the success <br />Attachment 2.04.1OC Page 25 May 2017 (TR -14) <br />