Tratamento do solo com cal para prevenção de erosão hídrica: uma proposta de metodologia para uso em taludes de pilha de estéril

Abstract

Rainfall erosion in waste dumps can cause structural, economic, and environmental damage. The treatment of soils with lime is known and used widely worldwide for the construction of landfills for roads and highways. It is a process that aims at soil stabilization, improving workability and mechanical properties after compaction. Some studies have been conducted evaluating the influence of lime on soil erodibility, in which it was observed that this treatment increased resistance to soil erosion. Knowing that the treatment of soil with lime has potential for use, and the need to study and propose alternative techniques, complementary or more economical than existing ones to mitigate erosive processes, it is intended to verify the efficiency of this treatment in increasing the resistance to surface erosion caused by the impact of raindrops on the soil surface of mine waste dump. For this, mass loss tests by immersion of the MCT methodology and experiment tests in the EFA apparatus (Erosion Function Apparatus) were carried out in Exhibitions with different percentages of lime in mass (1%, 2%, 3% and 4%) and without lime as a reference. The results indicated that the erodibility of soils treated with 2% to 3% lime by mass was reduced by 10 to 27.4 times, respectively. This degree of reduction has the potential to reduce or eliminate the need to implement sediment containment dikes in waste rock piles, taking into account the risks inherent to mining activities.