2008-05-13_REVISION - C1981008 (5)

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New Horizon Mine: 2007 Vegetation Sampling for Phase 2 Bond Release • 4. Dryland Pasture Reference Area (6.7 acres). This area is vacant unmanaged and adjacent to the Nucla Airport. The reference area was established several years ago and the vegetation was measured in summer 2005 for comparisons with other New Horizon Mine Permit 1 reclaimed lands. 5. Dryland Pasture Reclaimed, Phase 3 (21.9 acres). This area is in its first year of eligibility for Phase 3 vegetation measurement. WFC is also applying for Phase 2 bond release on this area. 6. Dryland Pasture Reclaimed, Phase 2 (59.4 acres). This area includes the Phase 3 Dryland Pasture reclaimed lands described above, and additional reclaimed lands eligible for Phase 2 measurement but not yet eligible for Phase 3 measurement. 2.2 Sampling Procedures A field crew of 3 to 4 botanists conducted fieldwork from June 4 to June 22, 2007. For each of the 6 study areas described above, in ESRI ArcMap (a GIS computer application) we created a polygon shapefile defining the study area boundary, then used a GIS application to generate at least 50 random point locations in each study area. We uploaded the sample points into Garmin GPS units (average accuracy 15 feet) and used the GPS units to navigate to sample points in the field. A few sample points were rejected in the field because they fell in areas at field margins not typical of the reclaimed land or reference area land being measured, for example a mowed road berm. • Cover was measured by a point intercept method. From random sample points, a 100 ft. tape was stretched at a bearing of magnetic north (if a bearing caused the tape to cross the study area boundary, then bearings of east, south, or west were substituted, in that order). At 10 foot intervals along the tape beginning at 10 feet, a point frame was positioned perpendicular to the tape and extending to the left. The point frame consists of a metal bar with tripod legs, positioned parallel to the ground about 1 meter high. A sliding laser light pointer is positioned at each of 10 marked points along the bar spaced 10 cm apart. At each point the observers record the object that first intersects the downward-pointed laser light (plant species, litter, rock, or bare ground). Ten cover readings at each of 10 intervals along the transect yield 100 cover readings per transect, which are tallied and the total number of hits per species or object is equal to the percent cover estimate for that transect. Production was measured by clipping and weighing current year above-ground herbaceous growth within a square 0.25 m2 frame (irrigated pasture) or a rectangular 2 m2 frame (dryland pasture). Clippings were segregated into paper bags by perennial grass, annual grass, perennial forb, annual forb, noxious weed, and a few individual species (such as broom snakeweed on the dryland pasture reference area, pending decisions on how to group plant species for analysis). Bags were oven-dried at 90 degrees C to a constant weight, then the contents weighed on a calibrated electronic balance to the nearest 0.1 g. For both cover and production, samples were taken in each study area until either sample adequacy was reached (see statistical procedures, below) or a minimum of 15 to 30 samples was reached, depending on the statistical methods. Sample adequacy was calculated • periodically in the field during sampling by entering cover data and fresh weight production data into a field laptop computer. After production samples were dried, sample adequacy was BIO-Logic Environmental 6 November 12, 2007