Reclamation after Gold Mining: implication of Reclamation Practices on Soil Physicochemical Properties and Heavy Metal Concentration

Post-mining land reclamation, involving techniques such as re-contouring, back-filling, slope stabilization, and drainage management, has become a cornerstone of sustainable mining operations, particularly in Ghana, where environmental awareness and the need to mitigate mining impacts are growing. This study assessed the effectiveness of reclamation practices implemented by three major mining firms, focusing on changes in soil physicochemical properties and heavy metal concentrations. The investigation was conducted at three distinct mine sites, designated as Site 1, Site 2, and Site 3, with adjacent undisturbed areas within each mining concession serving as reference sites for baseline comparison. Soil sampling was systematically carried out within designated plots on both reclaimed and reference sites. At each plot, five composite soil cores were collected at two depths (0–20 cm and 20–40 cm) to evaluate variations in surface and subsurface soil conditions. Analytical results revealed consistently elevated concentrations of heavy metals, including mercury, cadmium, and copper, in reclaimed sites compared to their corresponding reference areas across both depths. Geo-accumulation indices indicated moderate contamination levels in specific reclaimed zones, underscoring persistent environmental challenges. Effect size analysis further confirmed that reclamation interventions have not yet fully restored soil quality to pre-mining conditions, despite evidence of progressive remediation efforts aimed at improving soil health and reducing contamination over time. These findings highlight that while current reclamation strategies contribute positively to environmental recovery, significant gaps remain in achieving full restoration of soil health to baseline conditions. The persistence of elevated heavy metal concentrations emphasizes the need for enhanced reclamation approaches, including long-term monitoring, advanced soil amendment practices, and targeted remediation of contaminants. Such improvements are critical to ensuring that post-mining landscapes meet acceptable environmental standards and more closely align with pre-mining ecosystem characteristics. This study underscores the importance of refining reclamation programs to address these challenges effectively, thereby supporting sustainable environmental recovery and minimizing the long-term ecological footprint of mining activities in Ghana and similar mining regions globally.