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<br />Vegetation Study: New Horizon Mine, New Airport Re/erence Area (OMarM Pesarrcl <br />7.0 INTRODUCTION <br />New Horizon Mine requests the establishment of a new dryland pasture reference area as the <br />standard by which to judge revegetation of redaimed coal mine lands. Vegetation at the <br />previousty approved reference area near the Nucla airport was last sampled in 1999 (vegetation <br />production) and 2000 (vegetation cover). The purpose of this stutly is to measure vegetation <br />production (live current year growth) and cover (five) on the new reference area, and to <br />compare production and cover with the previous reference area to determine if the new <br />reference area will be adequate as a standard for reclaimed lands with apost-mining use of <br />dryland pasture. <br />2.0 STUDY ARFJ1 DESCRIPTION <br />The crew reference area is adjacent to the old reference area (see attached map), and is similar <br />in landfgrm and soils. The area is ad}acent to the Nuda sirpoct on a flat mesa. Native <br />vegetation was dominated by big sagebrush, other native shrubs,.occasional scattered Utah <br />juniper, and perennial grasses and forts. At (east 10 years ago the native shrubs were Geared <br />and the area was seeded for livestock forage and grass cover. <br />3.0 SAMPLE POINT SELECTION <br />A 50-foot grid was created in CAD and ovedaid on the new reference area boundary on a <br />• ~ georeferenced dig0al aerial photograph. Each grid square wholly wdhin the new reference area <br />was consecutively numbered, and geographic coordinates of the centers of each gdd square <br />were.detennined in CAD. Fifty gdd square numbers to be sampled were rendomty selected <br />using a random number function in Microsoft Excel, and geographic coordinates of the selected <br />grid square centers were loaded into a Garmin GPS-V GPS unit which was used to navigate to <br />the seleded.sample points. <br />4.0 SAMPLING METHODS <br />Transacts and Cover Measurement <br />Cover measurements were made on May 20.22, 2005. Vegetation cover was measured by the <br />pointintercept method, using a laser point bar. After aniving at each sample point, a stake was <br />thrown over the shoulder to mark the start point of the trensect. A 1D0-foot tape was laid out <br />from the trensect start point on a bearing randomty determined by a random number function in <br />Microsoft Excel. At 10.foot intervals from 10 to 100 feet on the tape, the laser polM frame was <br />setup perpendicular to the tape. The intercept of the laser point was recerded at 1 D points <br />(spaced at 10 cm) at each 16-foot imerval, providing 100 cover measurements per transact <br />Intercept was recorded as bare ground, litter, rode, or plant spades. The total number of'hits' <br />for each plant spades or substrate type was summed for each transact to determine percent <br />cover. <br />Cover samples were taken at the random sample poins in order, unbl sample adequacy was <br />reached according to the following formula: <br />9IOLog/c Environmental , <br />Jury 2005 <br />• <br />(Revised August20os) Attachment 2.04.10-4-3 <br />