AAI was contracted by Graymont to perform a study of alternative accesses from surface to the underground limestone mine at Pleasant Gap, Pennsylvania. The options included two declines through existing workings, new declines from surface to access future mining areas, and a hoisting shaft to access future mining areas. In addition to hoisting from the proposed shaft, the options considered for haulage to the existing crusher included truck haulage and belt conveyors. The analysis included a comparison of the capital costs for excavation of each option together with capital and operating cost estimates for each haulage option.
