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<br />DETERMINING FINAL REVEGETATION SUCCESS <br />CEC has elected to use standards developed from vegetation monitoring events between 1994 <br />and 2005 at the Osgood Sand Reference Area, for the evaluation of revegetation success at the <br />Keenesburg Mine site. With the approval of TR-37 (6/15/2006), sampling of the Osgood <br />Reference Area was discontinued. Beginning with the 2006 sampling event, total vegetation <br />cover and total herbaceous production are evaluated through values calculated from predictive <br />equations based on growing season precipitation at the mine. For the parameter of species <br />composition, a quantitative success standard based on relative cover was developed by the <br />Colorado Division of Reclamation, Mining and Safety, and CEC. Since there is no requirement <br />for the replanting of woody plants, there are no woody plant density success criteria. <br />In 2012, CEC revised the predictive equations for establishing final revegetation success <br />standards for vegetation cover and herbaceous production. The revised equations <br />removed plant species identified as ineligible by CDRMS, and provided an equitable <br />basis for comparison of the derived standards for current and future revegetation at the <br />mine. These revised equations (and standards) were approved in TR-43. <br />In 2020, CEC revised the species composition standard to remove the species <br />seasonality requirement for current and future revegetation at the mine. This revised <br />standard was approved in TR-47. <br />Sampling Methods <br />The reclaimed area(s) will be sampled to allow a determination of sample adequacy. The <br />reclaimed area may be treated as a single type or divided into parcels, based on seeding date or <br />other logical criteria. Sample locations within all reclaimed parcels will be randomly selected <br />using randomly generated grid coordinates overlain on a map of the mine. <br />Transect and quadrat locations are randomly selected prior to the commencement of field work. <br />The reclaimed area(s) to be sampled are divided into a grid on the mine map. Horizontal and <br />vertical axes are assigned a unique alphabetic or numeric character. Characters are then <br />randomly generated, and sample points established based on their unique \[x,y\] Cartesian <br />coordinates. Extra sample points are generated and plotted to be used if a given location is not <br />available for sampling (e.g., the sample point falls on an 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 length <br />are proposed for the reclaimed areas at the mine. A total of fifty points will be collected per <br />transect, using point transect methods. Each transect will serve as a sample unit. Points will be <br />collected using a stationary optical sighting device to maximize reproducibility and precision. In <br />multiple layers of vegetation, first hits are recorded for total vegetation cover, while subsequent <br />"hits" will be used to calculate relative vegetation species cover. Vegetation cover data will be <br />collected from the appropriate reclaimed area(s). For bond release, sufficient numbers of <br />samples will be collected to reach sample adequacy. <br /> ЊЊЏ АΉЋЉЋЉ <br /> <br />