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vegetation cover and site conditions, the Division has determined that the sediment pond is no longer necessary to control disturbed area sedimentation. As such, the Division proposes to discontinue maintenance of the sediment pond spillway riser structure. Leakage of occasional inflows into the buried discharge culvert will be allowed to continue. The Division has chosen to make the demonstration that conditions of Rule 4.05.2(2) have been met, to allow for discontinuance of sediment pond maintenance. Rule 4.05.2(2) requires (in pertinent part) that sedimentation ponds be maintained until "... removal is authorized by the Division and the disturbed area has been revegetated and stabilized," and "the untreated drainage from the disturbed area ceases to contribute additional suspended solids above natural conditions". An additional requirement of 4.05.2(2) is that sediment ponds must be retained and maintained for at least 2 years after the last seeding within the affected watershed. Further, it is Division policy is that sediment ponds must be retained and maintained until a statistically valid demonstration of compliance with the approved vegetation cover standard has been made. The Division conducted vegetation cover sampling in May 2005, and site stability evaluation was conducted during the 2005 growing season (see May and September 2005 DMG inspection reports). Results of these evaluations indicate that the cover standard has been met, and the disturbed area has been stabilized. Quantitative Assessment of Vegetation Cover Vegetation cover sampling was conducted by the Division on May 17 and May 18, 2005. Thirty randomly located, randomly oriented, 10 meter vegetation cover transects were run. At each transect, a tripod mounted ocular 10 point frame was set up every 2 meters, for a total of 50 readings per transect. At each of the 50 points, "hits" were recorded by vegetation species (for live vegetation), litter, rock, or bare ground. The cover summary is presented in Enclosure 1, cover statistics including sample adequacy documentation and demonstration of success is presented in Enclosure 2. Representative photographs of revegetated areas taken in September 2005 are included in Enclosure 3, and a site map showing sample transect locations is included in Enclosure 4. The sole vegetation standard applicable to the Fruita Mine is vegetation cover (because of the extensive pre-law disturbance at the site). The mine was never permitted under the permanent regulatory program, but the Division had proposed a cover standard of 25% in a findings document that was prepared prior to forfeiture of the reclamation bond. Based on the data collected, the standard was easily exceeded this year. The applicable criteria is 22.5% vegetation cover (90% of the approved standard). The sample mean from the cover data collected by the Division was 43.9%, and minimum required sample size was calculated to be 29.6, based on the standard sample size adequacy formula. As such, the data comprise a statistically valid demonstration of compliance with the cover standard. Annual species, particularly downy brome, or cheatgrass (Anisantha tectorum), provide a major component of the vegetative cover. Downy brome and other annual species are present at similar or higher levels in undisturbed habitats in the mine vicinity. Growth of annual species was enhanced in 2005 by relatively wet conditions in the fall of 2004 and early spring of 2005. However, seeded perennial species are also well established at the site, particularly several species of native shrubs. Seeded perennial species comprise approximately 35% relative vegetation cover.