Granitic Mining Waste Feasibility for Liner Material Production

This work aims to characterize geotechnically and mechanically a granitic mine waste (MW), a clayey soil, and two mixtures of M:soil with 50% and 25% of (dry mass), looking to evaluate its feasibility for liner material production. Samples of MW, soil, M:soil(50:50%) M:soil(25:75%) were analysed in terms of specific gravity (GS), coarse and fine portions granulometry distributions, Atterberg limits (WL and WP), Normal Proctor compaction parameters (wopt and ρd,opt), oedometer compressibility test, consolidated undrained (CU) triaxial compression and hydraulic conductivity (k). MW showed finer granulometry, and higher plasticity than the soil, possibly showing filling properties for the mixtures, lower GS and ρd,opt indicating weight-reduction for a new liner material development. Furthermore, k values can reach the requirement for liner application of a minimum of 10-9 m/s, although it needs more investigation on leachability capacity, cation exchange capacity and chemical compatibility in case addition of chemicals are needed for improving mixtures properties for liner material.