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_. DIVISION OF MINERALS AND GEOLOGY Department of Natural Resources 1313 Sherman St., Room 215 Denver, Colorado 80203 Phone: (3011 866-3567 Fnx: lay 2~; 61996 iii iiiiiuiniiiiii 999 STATE OF COLORADO To: Bourg File, C-81-021 From: Janet Bin Re• 1995 Bourg ~ual Reclamation Report Review ~~~ DEPARTMENT OF NATURAL RESOURCES Roy Romer Governor lames S Lxhhead Exentlive Director • ' Michael B Long Drvuion Director I have reviewed the 1995 Bourg Annual Reclamation Report and vegetation sampling report. The Mine site has been reclaimed. Backfilling and grading occurred in 1988. 33 acres were seeded with the permanent seed mix in September 1984, and the remaining 110 acres were seeded in October 1988. The Northgate load out was seeded in 1988. The Load out site was approved for phase II and III bond release on March 15, 1996. The facilities area was approved in 1988, MR-08, to remain as a gravel pad. Two cement pads, a water well, a septic field and the perimeter fence was approved to remain too, to support the post-mining land use of rangeland and wildlife habitat. This gravel area encompasses approximately 2.5 acres. The mine site was sampled August 3, 1995, by Keammerer Ecological Consultants and this data submitted in the 1995 Annual Reclamation Report. The 1984 seeded area was sampled separately from the 1988 seeded area. Data from both areas has been consolidated in the report. There is a marked difference in species composition between the two sites. Age of stand could be one contributing factor in the diversity difference between the two stands: eleven growing seasons vs. seven growing seasons. In the 1984 Seeded area, sagebrush (Atemesia tridentata) was the dominant species comprising 64.9% of the relative cover. Sagebrush has shown a general increase in cover over the years. Thickspike wheatgrass (Agropyron daystachyum) was the. second most abundant species at 15% relative cover. Green needlegrass (Stipa viridula) and Russian wildrye (Elymus junceus) were next in importance at 8.75% relative cover each. Other perennial forbs were present at very low frequencies as well. Overall, looking at the last seven years of data, cool season perennial grasses are showing a general decrease while introduced perennial grasses are increasing in frequency. Eleven species of perennial forbs comprise 2.8% relative cover. Surface litter remains fairly stable at approx. 40%. Tota] live vegetative cover remains fairly stable at approx. 27%. This was a decrease over the 1994 cover value of 31%. This decrease may be attributed to the poor growing season experienced in 1995, (Dry winter, cold late spring, cool and wet into July). In the 1988 seeded area, species composition was heavily dominated by Russian wildrye at 65.6% relative cover, while Thickspike wheatgrass accounts for 24.8% relative cover.