2010-01-22_REVISION - C1981008 (2)

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C-1981-008 PR-06 PAR 22-Jan-2010 Page 23 of 26 c) Field harvest yield determination methods for reclaimed area and reference site are addressed generally in subsection 6.1.3 and more specifically in subsection 6.1.4. Statements in both sections indicate that fresh bale weights would be recorded in both reference and reclaimed sites, with no adjustment to dry weight. However, subsection 6.1.4 narrative states that the harvest measurement method would be consistent with the method used in 1987 to determine baseline production. The 1987 methods are described in subsection 4.7 of Section 2.04.10. With respect to drying, the procedure is detailed as follows: At the time of weighing, sub-samples of hay were collected from a portion of the bales, weighed using Pesola field scales, bagged and labeled, and returned to the laboratoryfor analysis. In the laboratory, sub-samples were dried at 30 deg. Cfor 72 hours, or until constant weight was obtained, and re-weighed using an Ohaus top-loading electronic balance which is accurate to 0.01 gm. This provided an adjustment factor needed to determine dry weight production for the fields. The hay production in the fields, expressed on a dry weight basis as pounds/acre, was calculated by multiplying the total number of bales counted in afield by the average adjusted bale weight and dividing by the size of the field in acres. Obtaining fresh weight and dry weight subsamples in the manner described to derive an adjustment factor is important to ensure an "apples to apples" dry weight based comparison of reclaimed area and reference site production. Please amend the yield determination procedure in subsections 6.1.3 and 6.1.4 to address subsample collection, weighing and drying, and derivation of "dry weight adjusted" bale weights consistent with the 1987 baseline procedure, for use in production success comparisons. d) The production success demonstration approach proposed is in essence a total harvest method, since the entire reference field and the entire bond release field would be mowed and baled. The sampling component of the demonstration would be limited to weighing an adequate number of randomly selected bales to establish an accurate average bale weight, with sub-sampling of the selected bales to establish an appropriate fresh/oven dry adjustment factor. The bond release area adjusted production (avg. adj. Bale wt. * number of bales divided by acreage) would be determined for each of the three sampling years and the 3 year average adjusted production would be compared to the appropriate 3 year (+) average adjusted reference field production determined in the same manner. Given the fact that the approach is a modified total harvest involving comparison of averages derived from harvest data collected over multiple years, much of the sampling and statistical detail provided in sub-section 6.1.4 would not apply. We recommend that the 3`d sentence following the sample adequacy formula be amended to state "Sampling will continue as necessary to reach sample adequacy."The remainder of the sentence should be deleted. The following paragraph beginning with "Reclaimed area production will be compared..." should be revised to correspond to the approach