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DETERMINING FINAL REVEGETATION SUCCESS <br />CEC has elected to use standards developed from vegetation monitoring events between <br />1994 and 2005 at the Osgood Sand Reference Area, for the evaluation of revegetation <br />success at the Keenesburg Mine site. With the approval of TR -37 (6/15/2006), sampling <br />of the Osgood Reference Area was discontinued. Beginning with the 2006 sampling <br />event, total vegetation cover and total herbaceous production are evaluated through <br />values calculated from predictive equations based on growing season precipitation at the <br />mine. For the parameter of species composition, a quantitative success standard based on <br />relative cover has been developed by the Colorado Division of Reclamation, Mining and <br />Safety, and Coors Energy Company. Since there is no requirement for the replanting of <br />woody plants, there is no woody plain density success criterion. <br />In 2012, CEC revised the predictive equations for establishing final revegetation <br />success standards for vegetation cover and herbaceous production. The revised <br />equations removed plant species identified as ineligible by CDRMS, and <br />provided an equitable basis for comparison of the derived standards for current <br />and future revegetation at the mine. These revised equations (and standards) <br />were approved in TR -43. <br />Sampling Methods. The reclaimed area(s) will be sampled to allow a determination of <br />sample adequacy. The reclaimed area may be treated as a single type or divided into <br />parcels, based on seeding date or other logical criteria. Sample locations within all <br />reclaimed parcels will be randomly selected using randomly generated grid coordinates <br />overlain on a map of the mine. <br />Transect and quadrat locations are randomly selected prior to the commencement of field <br />work. The reclaimed area(s) to be sampled are divided into a grid on the mine map. <br />Horizontal and vertical axes are assigned a unique alphabetic or numeric character. <br />Characters are then randomly generated, and sample points established based on their <br />unique [x,y] Cartesian coordinates. Extra sample points are generated and plotted to be <br />used if a given location is not available for sampling (e.g., the sample point falls on an <br />existing road or other structure). <br />Total vegetation cover. Vegetation cover transects will be randomly located within the <br />reclaimed areas. Transects will be of a length consistent with Colorado Division of <br />Reclamation, Mining and Safety regulations. At this time, quadrants of 25-50 meters in <br />length are proposed for the reclaimed areas at the mine. A total of fifty points will be <br />collected per transect, using point transect methods. Each transect will serve as a sample <br />unit. Points will be collected using a stationary optical sighting device to maximize <br />reproducibility and precision. In multiple layers of vegetation, first hits are recorded for <br />total vegetation cover, while subsequent "hits" will be used to calculate relative <br />vegetation species cover. Vegetation cover data will be collected from the appropriate <br />reclaimed area(s). For bond release, sufficient numbers of samples will be collected to <br />reach sample adequacy. <br />116 12/12 <br />