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REVEGETATION SUCCESS SAMPLING METHODS <br />As part of the termination of jurisdiction the Division conducted revegetation sampling at the <br />Twin Pines Mine on June 13-14, 2006 and June 27-28, 2007. The portal azea and coal loadout <br />azea were set up as separate sampling units. Data was collected on vegetative cover and <br />herbaceous productivity. A map of the Twin Pines portal area and loadout is attached to this <br />report. <br />Prior to collecting the field data for cover and production, a map was prepared with GPS <br />coordinates for the sampling locations. A random start, systematic 25 meter grid was established <br />over the portal azea and a 30 meter grid was set up at the loadout area. Cover and production <br />data were collected at fifreen points on the grid. Cover was collected along a 10-meter transect. <br />An optical 10-point bar was placed perpendiculaz to the transect at each meter along the transect. <br />A point-intercept observation was made at each 10-cm interval along the one meter point bar for <br />a total of 100 points per transect. Data was recorded on field sheets and analyzed in the office. <br />Live herbaceous production was collected using a harvest method. All the current years <br />herbaceous growth including grasses, fortis and sub-shrubs was clipped in 30 '/~ mz quadrats. <br />Quadrats were placed at the 0 mark on each transect and 15 other quadrats were clipped at <br />alternating points on the grid for a total of 30 samples at both the portal azea and at the loadout. <br />Clipped vegetation was bagged. The clipped vegetation was dried in ovens at CSU for 10 days <br />and then weighed. Bag weights were subtracted from the biomass calculations. <br />Sample adequacy for cover and production was calculated using the formula nm;,, = t z s z <br />(d Xnar)Z <br />RESULTS <br />Revegetation sampling was conducted on June 13-14, 2006 and June 27-28, 2007. This time <br />period coincided with maximum vegetative growth potential and development of the majority of <br />plant species found in both the native vegetation community and the reclaimed area to be <br />evaluated. <br />Weather conditions were a factor in the sampling results. In April 2006 Fremont County was <br />identified by the National Oceanic and Atmospheric Administration as under extreme drought, <br />the most extreme category. Conditions had not improved by the time sampling occurred in June <br />and abnormally high temperatures worsened the conditions. On June 13, the first day we <br />sampled temperatures were over 100° Fazenheit. The extreme drought conditions aze evident in <br />the vegetative data. 2006 total cover values aze at least 10% less than in 2007 and production is <br />at least 700 pounds per acre less. <br />Results from all the revegetation sampling are summarized on Table 1. An asterisk indicates that <br />sample adequacy was achieved for that sample population. The detailed spreadsheets are <br />attached at the end of this report. All species recorded from the cover sampling aze listed on <br />Attached Table 2. <br />2 <br />