STABILIZED COPPER MILL TAILINGS FOR HIGHWAY CONSTRUCTION

The results of an investigation to determine the feasibility of using stabilized copper mill tailings in road construction are presented. Properties of three types of tailings were evaluated after preliminary testing of several tailings from Arizona, Idaho, and Utah. The properties of the three tailings are summarized, and detailed results obtained for one type are reported. Index properties of the untreated tailings, including physical and mechanical properties, are given. Engineering parameters of untreated tailings are reported, including compaction characteristics; compressive, tensile, and shear strength; compressibility; permeability; and erodibility by rainfall. Properties of cement-stabilized and asphalt-stabilized tailings are also presented. The results demonstrate that copper mill tailings have excellent engineering properties and can be successfully used in road construction. In particular, the results indicate that there is excellent potential for using tailings as compacted fill in embankments, compacted foundation and subgrade material, cementlining canals, ponds, and reservoirs. (Author)