The project work will involve mitigating the subsurface coal fire by excavating the burning/smoldering coal and thoroughly blending the hot material with cold overburden until the temperature of the blended material is below eighty degrees Fahrenheit (80°F). The cooled and blended material will then be used to backfill the excavation. The excavation, blending and backfilling operations will occur in a “rolling” manner so that only a portion of the mitigation area is open at any one time. A portion of the mitigation area is planned to be re-developed for use as the Marshall Mesa Trailhead. In the areas planned for the trailhead re-development, compacted backfill will be required. All areas within the trailhead re-development will be rough graded to elevations provided in the Site Plans. Outside of the trailhead re-development area the mitigated areas will be graded to resemble the surrounding natural topography, seeded and hydro-mulched. It is estimated that 182,000 cubic yards of material will be excavated and blended during the mitigation process.
