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Of the azeas sampled in 2001, only the 1995 reclamation areas could meet the species • composition revegetation success criteria. Remaining reclamation areas fell short in the number of warm season grasses represented, while the Osgood sand reference area did not contain the requisite representation by perennial forbs. The concern with the current species composition success criteria has been documented previously (Savage and Savage, 1994, 1995, 1996, 1997, 1998, 1999, 2000). IV. DISCUSSION AND CONCLUSIONS Areas revegetated in 1995 and 1997, and those reseeded or interseeded in 1998 were quantitatively sampled in 2001 to evaluate revegetation establishment for monitoring purposes, and identify any azeas that require implementation of additional measures to ensure long term revegetation success. Two parcels within reclaimed areas, the area west of the dugout and a portion of the area south of the sediment pond, underwent controlled burning in May 2001 to control and reduce Bromus tectorum populations. The Osgood sand reference area was also quantitatively sampled to provide the revegetation success criteria values for total vegetation cover and total herbaceous production for the reclaimed areas governed by the requirements of CDMG Rule 4.15.8. 2001 PRECIPITATION REGIME The climate of the mine and surrounding area is characterized by a wide temperature • fluctuation; from below freezing in winter, to very warm in the summer months. Precipitation in the area is provided by weather systems originating in the Gulf of Mexico and is most frequent and reliable during the spring and late summer months (Table 10). Coors Energy Company has collected precipitation data at the mine for a number of years. This data represents the most complete record of precipitation from the mine area. Table 10 presents a summary of precipitation data collected from 1993 through 2001, corresponding with the most recent vegetation monitoring. A review of the data illustrates that precipitation is lowest during the autumn and winter months (October through March) and higher from spring through late summer. The months with the highest average precipitation are May and June. Based on the 1993-2001 data, average yearly precipitation was calculated. Additionally, two growing season precipitation periods were calculated based on the 1} months with reliable precipitation which was most likely to impact vegetation growth during a specific growing season (January-July), and 2) the period from the end of the growing season through the next growing season (September- July). From these averages, comparisons of individual yearly precipitation and its effect on specific growing seasons can be made. In 2001, precipitation conditions at the mine site were above average based on records from the mine site. Precipitation was significantly higher than average in April, May and July and lower in June. Cumulative precipitation for the January-July 2001 period was • 12.64 inches. Total cumulative precipitation for the period from September 2000-July -16-