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Mike Boulay <br />-12- July 8, 2011 <br />CAM - Response: The Division's comments regarding the perceived potential bias of <br />the vegetation sampling program are confusing and difficult to understand. Part <br />of the problem appears to be that the DRMS appears to have made assumptions <br />on how the data were collected that are inconsistent with the sampling approach <br />used. For example, they state that "the sampling sequence in the pre - <br />disturbance area is sequential" while the sampling on the Greasewood <br />Reference Area involved a combination of sequential and selective sampling. <br />These comments are not correct. All of the sampling on the site, baseline and <br />reference area was performed using a "random" sampling approach. None of the <br />sampling was performed in a "sequential" manner as suggested by the DRMS. <br />Perhaps in the theoretical world of textbook ecology, this is how it is done, but in <br />the field no one takes one sample, then travels miles away to the next sample <br />and then several miles back and so forth. In performing field work, time is not <br />wasted traveling back and forth across a mine site or project areal several miles <br />in width, to ensure that sampling is done in a "sequential" order. <br />What the DRMS has seemingly ignored is the excellent discussion found in Part <br />3, entitled "Vegetation Sampling Methods, Considerations and Design <br />Approaches" found in Division's Bond Release Guideline. Therein it states a <br />total of at least five times on pages 15 and 16 that all sampling must be <br />performed in an "efficient" manner. The concept of "efficiency" is totally ignored <br />in the DRMS comment which concentrates totally on the "theoretical" aspects of <br />"sequential" sampling and specifically concludes that unless "sequential" <br />sampling is performed the data a somehow biased. <br />The Bond Release Guideline which states on page 1 that this document takes <br />"precedence" of this document over the Vegetation Guideline, and further states <br />on page 15 that "vegetation sampling design approaches acceptable to the <br />Division include simple random sampling, and stratified random sampling design <br />modifications including proportional allocation and area weighted sampling. <br />Although not addressed in detail in this document, multi- stage, or cluster <br />sampling and systematic designs as discussed below may be adaptable to <br />certain reclamation situations, and may meet regulatory requirements when <br />design assumptions are met and specified procedures are followed." This <br />document further states that in instances where there is "difficulty of attaining <br />sample adequacy... operators are advised to give careful consideration to <br />sampling approaches which minimize variation among sample observations. <br />Such approaches might include with -in parcel stratification and acreage <br />weighting. Multistage or cluster sampling has been suggested as an approach <br />which might be of use in this respect." <br />This document also states on page 15 that in certain situations "systematic <br />sampling may be more efficient than random sampling." This concept is seems <br />to have been ignored by the DRMS who now states that random and systematic <br />sampling cannot not be performed together as this violates the "consistency in <br />sampling" requirement found in Rule 4.15.11(1) and yields biased data. <br />