This study addresses the pressing issue of utilising plastic from electronic waste as a filler to replace mineral sand. Currently, the use of plastic in construction concrete is limited due to a significant deterioration in the mechanical properties of modified concrete when plastic filler is added at levels exceeding 15–20%. As a result of the research, it was established that the addition of a nano-preparation—fullerene—in amounts as low as 0.001% significantly improves the mechanical properties of concrete with plastic aggregate. Replacing 50% of the mineral aggregate with plastic aggregate, combined with the addition of fullerene at a concentration of 0.01% of the mixing water mass, more than doubles the mechanical properties of the concrete compared to concrete without the nano-additive, with compressive strength increasing by 65.2%, from 16.33 MPa to 26.97 MPa. The impact strength and freeze–thaw resistance of the concrete were also significantly increased. This makes it possible to use concrete with a high plastic aggregate content of up to 50% without a significant reduction in mechanical properties. The use of machine learning and AI data processing methods such as AdaBoost and Random Forest allows for highly accurate prediction of the characteristics of the resulting materials, with a coefficient of determination (R²) for the resulting models close to 1.

Mine tailings from polymetallic ore processing may retain substantial inventories of valuable metals and therefore represent both a legacy environmental concern and a potential secondary mineral resource. This study evaluates three tailings storage facilities (TSFs) of different ages and operational histories—Talovskoye, Chashinskoye, and Starooye—in the Leninogorsk mining district, Rudny Altai, Eastern Kazakhstan. An integrated approach combining bulk geochemistry, the geoaccumulation index (Igeo), acid–base accounting, pH-dependent element mobility tests, and Landsat-derived NDVI for 2002–2026 was used to assess residual metal enrichment, geochemical stability, and the potential relevance of the tailings for future reprocessing. The tailings retain a distinct polymetallic signature dominated by Zn, Pb, and Cu, together with Cd, In, Ge, Te, Se, Au, Ag, and other associated elements. Their distribution varies considerably among the three facilities, indicating that potentially valuable components remain in materials produced during different stages of beneficiation history. The active Talovskoye TSF has the highest acid potential (128.75 kg CaCO₃/t), a positive net acid-producing potential (NAPP = +17.50 kg CaCO₃/t), an NPR of 0.86, the highest maximum element mobility (34.07%), and the lowest mean NDVI (0.029). In contrast, the older Chashinskoye and Starooye TSFs have negative NAPP values, substantially greater neutralization capacities, lower maximum mobility, and more developed vegetation cover. Starooye is of particular interest because a relatively stable vegetated surface and high neutralization capacity coexist with strong residual enrichment in several ore-related and associated elements. Thus, surface stabilization does not necessarily indicate either geochemical depletion or the absence of secondary-resource potential. The results show that residual metal inventories, element mobility, acid–base properties, and surface conditions need to be considered together when evaluating historical tailings. This approach provides a basis for identifying tailings that merit further mineralogical and metallurgical investigation before their technical and economic suitability for reprocessing can be established.