Hudson, E., B. Kulessa, P. Edwards, T. Williams, and R. Walsh.
Water, Air, & Soil Pollution 229:256(2018)

The mining and processing of metal ores at Esgair Mwyn, an abandoned mine in Ceredigion, Wales, UK, has left a legacy of environmental degradation. Flow gauging, water quality, and geophysics were combined in an integrated assessment of surface and subsurface hydrological contamination at the site. Heavy metals are affecting downstream watercourses, leading to widespread Environmental Quality Standards compliance failures. Through salt water dilution gauging and water quality sampling, a daily efflux of 876 g of heavy metals was calculated, with contaminant mobilization occurring mainly in two primary surface streams draining an exposed tailings heap. Electrical resistivity tomography subsurface imaging found a seepage plane within the tailings lagoon wall, while the main tailings heap became increasingly saturated with depth. A large adjacent field also had a high potential to convey pollutants in solution, yet its morphological characteristics have limited transmission, as the area acts as a type of passive treatment system. This site assessment approach provides a cost-effective way to identify the origins and pathways of contaminants and inform mitigation strategies focused on containment. This paper is Open Access at https://link.springer.com/article/10.1007/s11270-018-3880-4.