2017-03-10_REVISION - C1981019 (9)

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2.0 METHODOLOGY FOR VEGETATION SAMPLING / COMPARISON METHODS 2.1 Sample Site Selection / Location The sample layout protocol for revegetation evaluations in 2014 followed approved procedures set forth in Permit Section 4.15. The systematic procedure for sample location in the revegetated units occurred in the following stepwise manner. First, a fixed point of reference was selected for the unit to facilitate location of the systematic grid in the field. Second, a systematic grid of appropriate dimensions was selected to provide a reasonable number of coordinate intersections (e.g., 20) that could then be used for the set of sample sites. Third, a scaled representation of the grid was overlain on a computer- generated map of the target area extending along north/south and east/west lines. Fourth, the initial placement of this grid was implemented by selection of two random numbers (an X and Y distance) used for locating the first coordinate from the fixed point of reference, thereby making the effort unbiased. Fifth, where an excess number of potential sample points (grid intersections) was indicated by overlain maps, the excess points were randomly chosen for elimination. (If later determined that additional samples would be needed, the eliminated potential sample sites would be added back in reverse order until enough samples could be collected.) Sixth, utilizing a GPS, the sample points were located in the field. Once a selected grid point was located in the field, ground cover sampling transects were always oriented in the direction of the next site to be physically sampled to further limit any potential bias while facilitating sampling efficiency. This orientation protocol is indicated on Figure 1. If the boundary of the area was encountered before reaching the full length of a transect, the orientation of the transect was turned 90° in the appropriate direction so the transect could be completed. In this manner, boundary transects were retained entirely within the target unit by "bouncing" off the boundaries. 2.2 Determination of Ground Cover Ground cover at each sample point was determined utilizing the point -intercept methodology as illustrated on Figure 1. A transect of 10 meters length was extended in the direction of the next sampling location from the flagged center of each systematically located sample point. At each one -meter interval along the transect, a laser point bar was situated parallel to, and approximately 4.5 to 5.0 feet vertically above the ground surface. A set of 10 readings was taken specifically to record hits on vegetation (by species), litter, standing dead, rock (>2mm), or bare soil. Hits were determined at each meter interval 6