Historic coal mining and the associated processes have had a detrimental effect on the natural environment in the south Wales coalfield as contaminated mine drainage from abandoned mines discharges into the local hydrological system. The legacy of coal mining includes the discharge of contaminated mine drainage from several abandoned mines and the formation of insoluble iron minerals. This article discusses the underground processes that lead to the formation of contaminated water and iron minerals. Four abandoned coal mines located in the western part of the coal field and the remediation systems operational at these sites were investigated. Contaminated mine waters at these sites are being remediated through the removal of iron so that the final concentrations are in line with those recommended by the Water Framework Directive.
The legacy of coal mining in the south Wales coalfield: water contamination and remedial options
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