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small area within Reclamation Area 23, five cover transects and five total herbaceous <br />production quadrats were quantitatively sampled this season. Species composition data <br />was derived from the total vegetation cover data taken by plant species. <br />Sample sites were located in the field through compass triangulation and pacing from <br />known landmarks. The Coors Energy Company Keenesburg Mine 2012 Vegetation <br />Monitoring Sample Points figure (Appendix) illustrates the location of the reclaimed <br />areas and sample point locations. <br />All other areas reclaimed by CEC at the Keenesburg Mine have been released from final <br />liability by CDRMS, with the exception of Reclamation Area 25, which underwent <br />rehabilitation (plating with "yellow sand ", addition of Bio -comp) and reseeding this <br />season. <br />2.2 FIELD SAMPLING <br />2.2.1 Timing <br />Field investigation for Reclamation Areas 23, 29, 30, and 31 was undertaken during the <br />period August 7 -13, 2012. This time period coincided with anthesis and maximum <br />development of the majority of plant species found in the reclaimed areas at the mine site <br />and adjacent native areas. Total annual precipitation at the mine in calendar year 2012 to <br />date was below normal. Cumulative precipitation between September 2011 and July 2012 <br />(growing season precipitation) was 12.8 percent below the nineteen year mine average, <br />owing largely to below average precipitation in 2012 (5.09 inches). Precipitation in the <br />autumn and winter of 2011-2012 was significantly below average; with only October and <br />December 2011, and February 2012 exceeding monthly precipitation averages. Hot and <br />dry conditions throughout 2012 affected growth of both cool and warm season species, <br />with decreased overall growth, flowering, and seed set this season. <br />2.2.2 Vegetation Cover <br />Vegetation cover was estimated by the use of the point - intercept method. An ocular point <br />frame (ESCO Associates) was used to minimize instrument error and maximize precision <br />and observer accuracy. Cover transects were 25 meters in length, with two sample data <br />points collected at 1.0 meter intervals along the transect on opposite sides of the transect <br />centerline, 1.5m apart. Transect direction was established randomly through the use of <br />computer generated random directions (0- 360 °). In no event were transects allowed to <br />extend within ten feet of the revegetated area boundary to minimize impacts from "edge <br />effect." <br />For statistical purposes, each cover transect (comprising 50 data points) served as a <br />sample unit. Data points recorded the first vertical "hit" on vegetation (above or below the <br />instrument), soil (bare ground), rock, litter, or cryptogamic crust. Subsequent "hits" on <br />vegetation (prior to interception of the ground) were also recorded. Cover data were <br />recorded and reported by individual plant species. The first interception was used to <br />calculate total vegetation cover values. Additional interceptions were used to calculate <br />Coors Energy Company Keenesburg Mine Page 8 <br />2012 Revegetation Monitoring Report <br />