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Production <br />Herbaceous productivity success is calculated using a formula derived from historic data collected <br />on the reference area and precipitation data (TR37). The formula for herbaceous production is <br />y=0.3749x2*248S, where x is the cumulative amount of precipitation from September to the following <br />July, and y is the total herbaceous production in grams per square meter (g/m2). The total <br />herbaceous production success criterion calculated for 2007 was 165.22 g/m2. The total herbaceous <br />production success criterion calculated for 2008 was 39.66 g/m2, as a result of the low measured <br />precipitation of 7.95 inches measured from September 2007 to July 2008. <br />The 1985/1986/1987 BRB herbaceous production measured in 2007 was 239.46 g/m2. This value <br />exceeded the 2007 calculated standard of 165.22 g/m2. The 1995/1997 BRB herbaceous production <br />measured in 2007 was 229.27 g/m2. This value exceeded the 2007 calculated standard as well. <br />Both bond release blocks were sampled to statistical adequacy during the 2007 sampling. <br />The 1985/1986/1987 BRB herbaceous productivity was sampled to statistical adequacy in 2008 and <br />measured 144.68 g/m2. This value is over three times the 2008 calculated standard of 39.66 g/m2 in <br />spite of the low precipitation year. The 1995/1997 BRB was also sampled to statistical adequacy in <br />2008 and herbaceous productivity was 174.86 g/m2. This value was over four times higher than the <br />calculated herbaceous productivity standard for 2008. <br />Species Diversity <br />The diversity standard for the Keenesburg Strip Mine is described on page 116b of the permit. As <br />stated on permit page 116b, the reclaimed community will have "at least four perennial species of <br />which three are warm season perennial grasses and one is a cool season perennial grass. No one <br />component of the above species shall comprise greater than 40% relative importance nor less than <br />3% relative importance." Relative importance is measured using relative cover. Relative cover is <br />defined as the vegetative cover contributed by individual species divided by total vegetative cover. <br />The 2007 vegetation sampling of the 1985/1986/1987 BRB identified eight plant species with <br />relative importance greater than 3%. No single species contributed greater than 40% relative <br />importance. The four species that fulfill the species diversity requirement for the 1985/1986/1987 <br />BRB are Prairie Sandreed (24.1 % relative importance, or r.i.), Mountain brome (15.53% r.i.), Blue <br />grama (9.37% r.i.), and Sand bluestem (7.5% r.i.). Of these species, Prairie sandreed, Blue grama, <br />and Sand bluestem are warm season grasses, while Mountain brome is a cool season perennial <br />grass. None of the species measured at greater than 3% relative importance are considered noxious <br />or prohibited plant species. The 2007 sampling event for the 1995/1997 BRB identified the top <br />four species in order of relative importance as Mountain brome (17.35% r.i.), Sand dropseed <br />(12.98% r.i.), Blue grama (11.66% r.i.), and Prairie sandreed (9.27% r.i.). Of these four species, <br />three are warm season perennial grasses and one is a cool season perennial grass. <br />During the 2008 vegetation sampling of the 1985/1986/1987 BRB, the four perennial plant species <br />with the highest relative importance were Mountain brome (32.11 % r.i.), Blue grama (20.35% r.i.), <br />Prairie sandreed (11.40% r.i.), and Sand bluestem (7.19% r.i.). These four species met the <br />C1981-028, SL4 7 10/19/2009