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2009, and 28.65% live vegetative cover for 2010. <br />Given this, reclamation success was achieved for cover for 2009 on the reclaimed parcels, but not for <br />2010. The sample data was sampled to statistical adequacy for both years of sampling, 2009 and 2010. <br />The Division guidelines and Rule 4.15.11(2)(b) allow for reverse null analysis if the reclaimed sample <br />mean is less than 90 percent of the relevant standard. For 2010, the relevant cover standard is 32.65% <br />Live Vegetative Cover (36.28% X 0.90). Applying the "standard null" t -test formula as found in Rule <br />4.15.11(2)(b), the Division found that the live vegetative cover for 2010 does not meet the required <br />cover success criteria. <br />As discussed above in order to address this issue, CEC conducted revegetation monitoring for the same <br />parcels in August of 2011 to measure vegetative cover and diversity (species composition). After a <br />meeting with CEC and a discussion with Division management, staff agreed that the vegetation data <br />collected in 2011 could be used to measure reclamation success for the cover and species diversity <br />standard. This determination was made based on Rule 4.15.7(5) which required success criteria be met <br />for a minimum of two years out of the last four year of reclamation liability. The 2011 data for cover <br />and diversity fall within this timeframe and is therefore acceptable. <br />In 2011, the proposed bond release reclamation parcels were sampled using the same methodology used <br />in 2009 and 2010. Precipitation measurements between September of 2010 and July of 2011 totaled <br />13.37 inches as reported on page 2 of the2011 Quantitative Vegetation Study submitted as a response to <br />the Division's adequacy review received on December 22, 2011. Calculation of the required vegetative <br />cover standard for 2011 using 13.37 inches of precipitation resulted in a reclamation success cover value <br />of 35.41 %. Ninety percent of this calculated value is 31.87 %. After the removal of Cheatgrass from <br />the data, the vegetation cover was measured to be 42.80% which exceeds the cover success standard. <br />The sample size was found to be adequate using the formula from Rule 4.15.11(2)(a). <br />In summary, the reclamation success standards for cover was achieved based on the 2009 and 2011 data. <br />Production <br />The reclamation success criteria for herbaceous production on the Keenesburg Mine is based upon a <br />predictive equation based on cumulative applicable precipitation values. The formula is <br />y= 0.3749x2.2485, where x is the cumulative precipitation from September -July. Total herbaceous <br />production success standard for 2009 is 135.07 g/m2 (1205 pounds /acre, 13.71 inches applicable <br />precipitation). The 2009 production data was collected to statistical adequacy. The mean total <br />herbaceous production measured in 2009 was 261.13 g/m2, (2330 pounds /acre). Productivity was <br />achieved on the reclaimed areas in 2009. <br />Total herbaceous production success standard for 2010 is 156.78 g/m2(1399 pounds /acre, 14.65 inches <br />applicable precipitation). The mean total herbaceous production measured in 2010 was 175.20 <br />g/m2(1563 pounds /acre). Productivity was achieved on the reclaimed areas in 2010. <br />Page 6 <br />