Geochemical behavior and environmental risks related to the use of abandoned base-metal tailings as construction material in the upper-Moulouya district, Morocco

Abstract

In some developing countries, base-metal residues that were abandoned in tailing ponds or impoundments are increasingly used as construction material without any control, engineering basis, or environmental concern. This uncontrolled reuse of mine tailings may constitute a new form of pollution risks for humans and ecosystems through metal leaching. Therefore, the aim of the current study is to assess mine drainage, metal mobility, and geochemical behavior of two abandoned mine tailings commonly used in the upper-Moulouya region (eastern Morocco) as fine aggregates for mortar preparation. Their detailed physical, chemical, and mineralogical properties were subsequently evaluated in the context of developing appropriate alternative reuses to replace their conventional disposal and limit their weathering exposure. The obtained results showed that both tailings contain relatively high quantities of residual metals and metalloids with lead (ranging between 3610 and 5940 mg/kg) being the major pollutant. However, the mineralogical investigations revealed the presence of abundant neutralizing minerals and low sulfide content which influence mine drainage geochemistry and subsequently lower metals mobility. In fact, leachate analyses from weathering cell kinetic tests showed neutral conditions and low sulfide oxidation rates. According to these results, the tailings used as construction material in the upper-Moulouya region have very low generating potential of contaminated effluents and their reuse as aggregates may constitute a sustainable alternative method for efficient tailing management.

Utilization of tailings in cement and concrete: A review

“…Figure 2 presents the XRD pattern of lead-zinc tailings coming from different resources. Previous research [21] reveals that the mineral phases of the lead-zinc tailings include calcite, dolomite, quartz, kaolinite, galena, pyrite and gypsum, whereas other research [34] exhibits that there are two types of different lead-zinc tailings -one type has quartz, orthoclase, barite, albite, and chlorite as the main minerals phases; and the other has dolomite, calcite, barite, and quartz. The mineral phases of pyrite tailings include kaolinite and pyrite [35], but the main mineral phases of phosphate tailings are dolomite and apatite, according to XRD patterns [32] shown in Figure 3 and Figure 4.…”

“…The size fractions of tailings are classified as "sand", "silt", and "clay" based on a variety of methods and standards in many mining operators [3]. With the progress of grinding technology, there [35] are more and more "silt" and "clay" in the tailings, and even if tailings are used as aggregate, the maximum size of tailings is less than 1 mm in some literature [34,36]. In general, the tailings have a highly rough and irregular surface [28], since the grindability of various mineral phases in the tailings is different.…”

Manufacture and Characterization of Fired Bricks from Gold Mine Waste Rocks

“…Loutou et al [28] and Bayoussef et al [29] produced highperformance ceramics and lightweight aggregates using phosphate sludge and clay byproduct from phosphate mines. Argane et al [30][31][32] and Elmachi et al [33] used mining wastes as alternative fine sands for mortar and aggregates for concrete. Cementitious materials, including geopolymers and ecological cement, were developed using phosphate mining by-products [34,35].…”

Phytostabilization of store‐and‐release cover made with phosphate mine wastes in arid and semiarid climate using wild local plants

“…All of them are situated in the region of Marrakech, which is one of the most important metal mining provinces of the country (Lghoul et al, 2014). The geological and geographical features, wastes geochemistry, as well as their environmental impacts of these mine sites, were reported by Argane et al (2016), Goumih, El Adnani, Hakkou, and Benzaazoua (2013), andBussière, (2008a, 2008b).…”