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Of the areas sampled in 2005, none of the reclamation azeas satisfied the final species <br />composition revegetation success criteria. All reclamation azeas fell short in the number of <br />total perennial species. With the exception of the 2002 reclamation azeas, no azea contained <br />the requisite number of warm season grasses. The 1999, 2000, and 2002 reclamation areas <br />satisfied or exceeded the perennial forb criterion. The Osgood sand reference area did not <br />contain the requisite representation by total perennial species, warm season grasses, or <br />perennial. forbs with sufficient relative cover. The concern with the current species <br />composition success criteria have been documented previously (Savage and Savage, 1994- <br />2000, 2000x, 2001, 2002, 2003, 2004). A technical revision requesting revision of the <br />species composition success criteria is currently under review by the Colorado Division of <br />Minerals and Geology (January 2006). <br /> <br />4.0 DISCUSSION AND CONCLUSIONS <br />Areas reseeded or interseeded in 1998 and those revegetated in 1999 and 2000 were <br />quantitatively sampled in 2005 to evaluate revegetation establishment for monitoring <br />purposes, and identify any areas that require implementation of additional measures to <br />ensure long-term revegetation success. The Osgood sand reference area was quantitatively <br />sampled to provide the revegetation success criteria values for total vegetation cover and total <br />herbaceous production for the reclaimed azeas governed by the requirements of CDMG Rule <br />4.15.8. Areas revegetated in 2002 were qualitatively sampled for the first time this season. <br />4.1 2005 PRECIPITATION REGIME <br />The climate of the mine and surrounding azea is characterized by a wide temperature <br />fluctuation; from below freezing in winter, to very warm in the summer months. <br />Precipitation in the area is provided by weather systems originating in the Gulf of Mexico <br />and is most frequent and reliable during the spring and late summer months (Table 12). <br />Coors Energy Company has collected precipitation data at the mine for a number of years. <br />This data represents the most complete record of precipitation from the mine area. Table 12 <br />presents a summary of precipitation data collected from 1993 through 2005, corresponding <br />with the most recent vegetation monitoring. A review of the data illustrates that precipitation <br />is lowest during the late autumn and winter months (October through Mazch), peaks in April <br />through June, and tapers off gradually until late autumn again. The months with the highest <br />average precipitation ate May and June. Based on the 1993-2005 data, average yeazly <br />precipitation was calculated. <br />Calendar year 2005 precipitation levels included seven months with lower than average levels <br />and five months with above average levels. Overall total precipitation for 2005 was <br />13.14 inches, and the mean from 1993 through 2005 is 12.50 inches. Precipitation in January <br />(41% below average), February (58% below average), March (32% below average), May <br />(35% below average), July (55% below average), August (16% below average), and <br />September (81 % below average) was for the most part significantly below average for the <br />calendar yeaz. Above normal amounts of precipitation in calendaz yeaz 2005 was recorded in <br />April, June, October, November, and December. <br />Coors Energy Company Keenesburg Mine Page 21 <br />2005 Revegetation Monitoring Report <br />