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i s Award Nomination for Excellence in Surface Coal Mining and Reclamation - USDI, OSMRE - 1990 September, 1990 Woody stem densities on undisturbed drainage areas averaged 4888 stemsfacre for all three years com- pared to 471 stems/acre in 1988, 897 stems/acre in 1989, and 1304 steins/acre in 1990 on reconstructed drainage areas. Flow rates have been significantly reduced [ollowing the installation of stock tanks and dozer basins on reclaim and spoil areas, respectively. Discharge readings were recorded from a 10-year, 24-hour parshall flume (with Stevens Water Level Recorder) located in the north end of the Coyote Gulch reconstructed drainage channel. The peak [low in 1987 (22.24 cfs) occurred as a result of a high intensity thunderstorm in June (.74" ppt) and caused severe erosion within the newly regraded drainage channel. In 1988, fol- lowing drainage reconstruction and water retention strategies, the peak Dow rate associated with a .53" precipitation event (June) registered .04 cfs of discharge water. Similarly, a high intensity thunderstorm in July 1989 (.75" ppt) resulted in a discharge of 1.73 cfs. The peak flow thtu far in 1990 was 1.44 cfs and occurred during March. In addition to assisting in runoff control, the proper trequenry and distribution of livestock ponds has aided in evenly spreading big game animal use over the entire reclaimed area, thus reducing their impact on vegetation establishment. Gully formation and sediment loss was significantly reduced in postmine drainageways when compared to pre-drainage reconstruction. in Coyote Gulch, for example, an estimated 99,4()0 cubic yards of sediment was lost to gully erosion and sheet and rill erosion from 1984-1987. Following treatment an estimated 1,360 cu yds of sediment is lost annually to sheet, rill and gully erosion. This is a reduction in the annual erosion rate of 24 times the pre-treatment erosion rates. Much of the success for the reduction in erosion rates mtut be attributed to the wide variety of erosion control materials, methods and sediment reducing measures that were used in reconstructing drainageways and adjacent reclaimed sideslopes. As a result of appropriate erosion control treatment in re-established postmine drainageways, Trapper Mine has not needed to clean a single sediment pond in two years. A net savings to Trapper Mine of $150,000 has been realized since drainage reconstruction was initiated and sedimentation pond cleaning ceased. The average cost for drainage reconstruction during the four year treatment period is $4.80 per linear foot (2.8 sq yds). Costs were based on an average 25-ft wide channel bottom and included all materials, equipment and labor. Conclusions As a strategy for soil conservation planning, the promotion o[ vegetation in combination with natural and/or artificial erosion control measures, has much to offer. Vegetation is one factor that can be easily manipulated by careful management. Beyond that, better vegetative growth, by selecting plants that are well adapted to a particular climate or soil, will almost always provide direct economic beneFts in terms of vegetation production, stability and reduced soil loss. Wildlife Aabitat improvement Big game animals are an important economical and esthetic commodity in northwest Colorado. Trapper Mining Inc. conducts mining activity just south of Craig in the heart of big game wuntry. Much of the permit area is located on the north-Cacing slopes o[ the Williams Fork Mountains, an area considered winter range for mule deer and elk. Prior to mining, many state and federal agency personnel felt Trapper's mining activity could negatively affect wintering mule deer and elk populations between the Williams Fork Mountains and the Yampa River. Since that time, Trapper Mine has developed an exten- sive reclamation and wildlife mitigation program to offset effects of mining on these game animals. This program encompasses many activities designed to benefit deer and elk and their habitat within the mine's permit area.