_GENERAL DOCUMENTS - C1981017 (263)

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operations. Approximately 60,000 cubic yards of refuse were excavated from the upper margins of the project area. Of this volume, 15,000 cubic yards of material were placed at one portion of the toe of the slope to act as a buttress. This material was placed in thin horizontal lifts, and compacted in place. The remaining 45,000 cubic yards of excavated refuse was hauled off-site approximately one-quarter mile to another area being reclaimed by the Inactive Mine Program. The material was used to create a gentle slope at the base of a vertical cut. In this way, excavation and selective placement of the refuse accomplished multiple goals; stabilization of the Huntsman project area by removal of mass from the top of an unstable slope, and creation of a safe, stable landform at a vertical highwall-like cut slope. During excavation operations, the exposed refuse was compacted by the heavy equipment. In order to promote soil adhesion, a light dozer was used to rip the face of the facility perpendicular to the fall of the slope. A topsoil substitute material was placed over the roughened face of the facility to an average depth of eight inches. Erosion at high altitude, relatively steep slope reclamation projects in high snow pack areas is a significant reclamation issue. At other nearby refuse piles reclaimed with bond revocation monies, traditional methods of interrupting long slopes were employed. However, methods such as cross-slope berms or terraces tended to fail, due in large part to the differential melting of snow pack on north facing slopes. Therefore, an innovative method of interrupting the slope was attempted. The method used to interrupt the slope was to create hundreds of small dozer terraces on the newly created Huntsman slope. The terraces were created by positioning the dozer at the base of the slope, and backing the dozer upslope approximately one-dozer length. The operator would then lower the dozer blade, and push downhill until approximately six to eight inches of soil had accumulated in front of the blade. This action resulted in the creation of a gently sloping terrace approximately eight inches tall, twelve feet wide (parallel with contour) and four feet long (perpendicular to fall of the slope). Following construction of a terrace,the dozer would back up the hill two lengths, drop the blade and push forward one length to create an up-slope terrace. This process was repeated across the entire face of the project area. Two years following project completion, the area suffered an invasion of various species of thistle, a listed noxious weed in Colorado. In order to control the weed invasion, an integrated pest management program was developed for the site. In partnership with the U.S. Forest Service and Pitkin County, the Division received a grant from the Colorado Department of Agriculture to control the weed invasion. Biologic controls were used the first year to greatly reduce the weed seed population. 500 goats were allowed to graze the property. The goats, if moved in an appropriate rotation,preferentially consume the thistle flowers, thus eliminating the seed source. In following years, spot spraying of remnant weeds served to essentially eradicate the problem. The area was reseeded in conjunction with the grazing program, and now supports a diverse vegetative community. Bear Creek Project Overview The purpose of this project was to enhance the stability of the area located east of the Huntsman project area. Slope stabilization was accomplished by reconstructing the slope of the facility through excavation and placement of refuse. Approximately 90,000 cubic yards of coal refuse was excavated from the upper half of the refuse disposal facility, and pushed down hill to create the design slope of 2.1 H:1 V to 2.5 H:IV. The material was 6