Abstract: Parts of Britain have large accumulations of metalliferous tailings derived from mining in the lath, 19th and 20th centuries. These tailings were never subject to land reclamation schemes at the time of mining and are situated very close to water courses. They cause considerable environmental damage in terms of contamination of soils, dust blow and pollution of water courses and groundwater. In some parts of the country mine drainage is a major part of river pollution. In recent years, particularly in Wales, efforts have been made to “clean up” these sites. This has involved using techniques to isolate and contain the spoil, diversion of water courses, and the installation of water treatment facilities and drainage and the establishment of a vegetation cover. Research is also being initiated to investigate ways of decontaminating these metalliferous spoils as an alternative to using covering systems to reclaim them.