Wolf Minerals ’ new tungsten mine near Plymouth in Devon immediate post closure and longterm post closure phases .
Minimising the problem A key water treatment strategy is to minimise the amount of contaminated water generated in the first place . This typically involves exclusion of oxygen from the reactive materials by flooding and sealing excavations ; placing waste materials under water ; covering rock dumps with a layer of low permeability material to prevent water and oxygen ingress ; or mixing pyritic material with acid buffering / neutralising materials to reduce the amount of acidity generated .
Treatment solutions How the residual contaminated water is treated depends on the contamination load and the required treated water standard . Treatment has principally focused on pH correction to circa neutral values and removing dissolved metals .
Where there ’ s a relatively low concentration of contamination ,
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