Remediation of Metalliferous Mine Waste

Tender description

Addressing metalliferous diffuse pollution from old, abandoned metal mine sites within UK river catchments is a priority due to the significant environmental impacts associated with the release of harmful diffuse pollutants. These mine sites both leach toxic metals like lead, cadmium and zinc and mobilise heavy metal containing sediments that are washed/leach into adjacent watercourses. This contamination impacts water quality, aquatic life and biodiversity. Proactively managing and mitigating diffuse pollution in these catchments is essential to restoring and preserving the ecological balance of the river systems, ensuring the safety of the water for future generations, and maintaining local economies that depend on both rivers and surrounding lands for employment, recreation and agriculture. The primary objective under this contract is to mitigate diffuse metalliferous pollution within complex topographic and ecological conditions by applying an innovative, proportional suite of techniques to stabilise mine wastes and interrupt erosion and infiltration pathways. Baseline data on soil chemistry, metals and microbial diversity will inform the design of multi-treatment trials to evaluate restoration materials and techniques across contrasting environmental conditions. We will be looking to consider a range of stabilisation methods, including bespoke technosols to be developed to address the diverse on-site substrates; bare spoil, early-stage biocrusts and spoil adjacent to established habitats. The approach will be sympathetic to natural ecological succession from primary non-vascular colonisers to mature native grassland and heathland communities.