2015-10-13_REVISION - C1981014 (12)

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According to the CDRMS regulations and previous written guidance received from Mr. Dan Mathews and Ms. Sandy Brown of the CDRMS for other projects, if sample adequacy is achieved on both the reclaimed and reference area with the minimum number of transects, and the reclamation sample mean exceeds 90% of the revegetation success standard, no statistical testing is required and success can be demonstrated by direct comparison. If sample adequacy is not achieved for any of the areas sampled, but the reclaimed sample mean exceeds 90% of the approved standard, then the "reverse null" statistical hypothesis can be used. As explained on page 18 of the Bond Release Guideline: If the parameter sample mean for the bond release block is equal to or greater than 90 percent of the reference area or weighted reference area sample mean, or 90 percent of the approved technical standard, revegetation is considered successful for the parameter. Other than a demonstration of adequate sample size, no statistical calculations are required in this case to document success. If the parameter sample mean for the bond release block is less than 90 percent of the standard, an operator may employ hypothesis testing to demonstrate that the difference is not statistically significant. Historical Data. There has been considerable historic data collected from the Southfield Mine area. While it is recognized that these data cannot be used to document the successfulness of the current reclamation efforts located at the Southfield Mine and Loadout Areas, it is felt that these data are useful in that they clearly document baseline conditions and trends for the reclamation being evaluated in this bond release evaluation. The initial baseline vegetation studies started in 1980, when Keenan, Inc., issued a report entitled "Vegetation Inventory - Reference Area Cover and Density Analysis, which has been carried forward in every permit renewal since that time. Included in this report were vegetation data pertaining to the Refuse Site Reference Area, Mine Portal Reference Area, and the Loadout Reference Area. Plant over was collected using the basal cover sampling methodology. The woody plant density analysis consisted of actual tree and shrub density counts. No forage production sampling was completed in connection with this sampling effort. In the summer of 2013, the first year of Phase III final bond release reclamation monitoring was performed. Data were collected for the parameters of plant cover, forage production and woody plant densities. These data were included in a report entitled "Revegetation Monitoring Report for the Phase III Bond Release Areas Sampled on the Energy Fuels Coal, Inc. Southfield Mine. The vegetation sampling methodologies used in 2014, were identical to those used in the 2013 sampling effort. In the summer of 2010, interim reclamation monitoring was performed on three reclaimed areas. The Loadout Reclamation was also sampled in this monitoring effort. Data were collected for the parameters of plant cover, forage production and woody plant densities. These data were included in a report entitled "Revegetation Monitoring Report for Reclaimed Areas Sampled in 2010 at the Southfield Mine. " Plant cover data were collected using the point intercept method and forage production measurements were taken by plant species