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cover transect and calculated that 64 quadrats were necessary to achieve sample adequacy. Due <br />to the small size of the reference azea, 0.8 acres, Greystone was unable to collect additional <br />samples without the concern of double sampling. <br />Greystone also chose to analyze the data from 2001 differently than the data collected in 2002 <br />although the sample design was the same. 2001 production data was compiled with respect to <br />the cover transect as called for in the design plan. 2002 data was analyzed as independent <br />quadrats. Both years of data collected needs to be analyzed using the same methodology. The <br />Division ran the adequacy statistics for 2001 data using each production quadrat data as an <br />individual value. Analyzing the 2001 production data in the same method as Greystone <br />analyzed the 2002 data found the 2001 reclaimed pasture data to have been sampled to <br />statistical adequacy, however, the 2001 reference azea pasture did not meet sample adequacy <br />using the same method of analysis. <br />Rule 4.15.8(4)(a) Requires that, "For herbaceous production the revegetated area shall be <br />considered acceptable if it is: <br />Not less than 90% of the production as determined from the reference area or approved <br />standard with 90%statistical confidence. <br />Fifteen transects lines with three production quadrats per line were collected in July 2001 <br />irrigated pasture. This data achieved statistical sample adequacy. 2001 irrigated pasture <br />reference area achieved sample adequacy with twelve transect lines with three production <br />quadrats collected per transect. 2001 Dry production weight on the irrigated pasture reference <br />area was 50.3 gf0.5 MZ. Productivity success required on the irrigated pasture for the 2001 data <br />is ninety percent of this value, 45.3 g/0.5 MZ. Herbaceous productivity measured on the <br />irrigated pasture in July 2001 was 137 g/0.5 M2. In 2001 productivity on the reclaimed irrigated <br />pasture faz exceeded productivity on the reference azea pasture. <br />Since statistical sample adequacy was not achieved on the 2002 productivity data, the Division <br />used the reverse null hypothesis testing to determine reclamation success. The "reverse null" <br />hypothesis presumes that the sample (reclaimed azea) mean is less than or equal to 90% of the <br />standazd and thus unsuccessful. Calculation of the reverse null hypothesis: ""The reclaimed area <br />mean is less than or equal to 90% of the reference area mean." was proven to be a false <br />statement indicating that the reverse is true, "the reclaimed azea mean is greater than 90% ofthe <br />reference azea mean." Thus, using the reverse null hypothesis, the Division can state that the <br />data supports that the reclamation is successful. <br />The "reverse null" hypothesis test is a more stringent test because the assumption is that the <br />reclamation has not been successful. In this situation, it is in the operator's interest to design a <br />powerful test so as to detect a true difference between the reclaimed area parameter and the <br />standard, if one exists, in order to reject the null hypothesis. For this reason, no statistical <br />sample size adequacy demonstration is required, as long as the minimum sample size as <br />specified in the bond release guidelines is met. In situations where the sample mean exceeds the <br />standazd by a substantial margin, it may be more efficient for an operator to demonstrate success <br />6 <br />