2012-09-06_REPORT - C1980006 (2)

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collected in 2009. These data are referred to as the RIVE 2005 data. These data are included only to document historic trends and not in any way to satisfy any of the required bond release vegetation sampling requirements. Statistical Analysis of Data. As required by the Division's regulations, it is not necessary to achieve sample adequacy for reclamation monitoring corresponding to the Phase III bond release sampling efforts provided that the success standard has been achieved, the reverse null hypothesis is used and that the required minimum number of transects have been sampled. According to the Regulations found in Rule 4.15.11 (2), a minimum of a least 15 transects for cover and 30 transects for production and shrub density must be collected even if sample adequacy is achieved with fewer transects. Therefore, all of the data collected in this evaluation were analyzed for sample adequacy in order to determine whether the Division's requirements had been satisfied. The sample adequacy formula contained in the DRMS regulations was used, wherein a precision of 0.10 was used for cover and production and 0.15 for shrub density. On all of the areas sampled, the field data were analyzed in terms of "total plant cover" to determine whether sample adequacy was achieved prior to leaving the site being sampled. On the reclamation blocks and reference areas sampled for production and shrub density, a minimum of 30 samples were collected and the data analyzed for sample adequacy before the reverse null approach was applied to determine revegetation success. According to previous written guidance received from Mr. Dan Mathews and Ms. Sandy Brown of the DRMS, if sample adequacy is achieved on both the reclaimed and reference areas, and the reclamation sample mean exceeds 90% of the standard, no statistical testing is required and revegetation success can be demonstrated by direct comparison. If sample adequacy is not achieved for one or both of the reclaimed or reference areas sampled, but the reclaimed sample mean exceeds 90% of the approved standard, then the reverse null statistical hypothesis, as found in the CDRMS regulations can be used. Results Field Sampling Dates. Most of the data utilized in this evaluation were collected between July 21 -25, 2009. Subsequent evaluation of the data revealed that some additional cover transects were needed, so the sampling was finished on August 29, 2009. At the time of the field sampling, all of the plants were actively growing and it is believed that the sampling was performed close to the period of optimum plant growth, when the plant cover and production were near their peak. A total of 75 plant species were identified in the 67 cover transects and 60 shrub density transects sampled in this evaluation. A list of all of the 93 plant species encountered in the field sampling efforts in this evaluation is presented in Table 1, Kerr Mine Plant Species List, Sample Adequacy. A statistical summary and analysis of the data collected to characterize the plant cover, production, and shrub density is presented in Table 2, Man Mine - 2009 Statistical Summary and Sample Adequacy Calculations. This table documents that a sufficient number of