2016-07-28_REVISION - C1981008 (2)

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4.2 Production For Irrigated Pasture bond release production comparisons, permit section 2.05.4(2)(e) specifies that a soil type correction factor must be applied to mean production for the Irrigated Pasture reference area to allow for variation in productivity of different soil types. For the Irrigated Pasture Phase III Bond Release Block, the Soil Adjustment Factor was calculated based on the acres of each soil type in the reclaimed area tract, and the soil productivity factor associated with the soil types (Table 4). Table 4 Soil Adjustment Factor Acreage Relative Acreage Assigned Production Factor weightedSol Index 10 36.4 16% 1.0 0.16 77 100.2 44% 0.8 0.36 78 59.5 26% 0.7 0.18 81 29.7 13% 1.0 0.13 Sol Adjustment Factor = 0.83 To calculate the Soil Adjustment Factor, the acreages were tabulated by overlaying the Irrigated Pasture Phase III reclamation parcels on the NRCS Soil Survey to represent pre -mining soils. Assigned Production Factors for each soil were obtained from Jim Boyd's October 2, 2007 letter found in Attachment 2.05.4(2)(e) — 11 of the permit. Jim Boyd, the local NRCS representative, reviewed the capability of all soils in the reclaimed area and assigned a relative factor to each of these soils. The adjustment procedure elevates the production success standard in situations where pre -mining soils were potentially more productive than reference area soils, and lowers the standard in situations where pre - mine soils were on average potentially less productive than reference area soils. In 2014, a minimum of 30 quadrats were sampled in each unit but sample adequacy was not achieved (Sample Adequacy Table presented above). Per Rule 4.15.8, a Reverse Null Hypothesis t-test must be used to demonstrate success. Statistical testing results are found on Table 5. Chart 5 displays the results from production sampling in 2014, and reveals that the Irrigated Pasture Phase III Bond Release Block exceeds the reference area comparison with 2,030.4 pounds per acre of desirable perennial production versus the 1,426.3 pounds per acre desirable perennial production standard (90% of 1,909.4 times the Soil Adjustment Factor of 0.83). Page 16