Nature Works Remediation Corporation

Dealing with high concentrations of sulphates and metals in ongoing mine drainage is one of the major problems connected with the closure of many base metal and coal mines. Large volumes of acidic water from the mines, waste rock piles and tailings can be generated. Usually, this acid rock drainage (ARD) cannot be disposed off until it has been treated in some way as it poses a direct threat to drinking water, agriculture, vegetation, wildlife and waterways. Traditional active treatment processes such as reverse osmosis or the addition of chemicals employed are often not very efficient and can be quite costly. In some cases they are simply not feasible. Therefore, alternative methods have to be considered. A bioremediation process in which sulphate-reducing bacteria (SRB) are used to decontaminate mine drainage in a wetland system is such an alternative: Sulphate-reducing bacteria are able to eliminate metals such as iron, zinc, copper, and others, neutralize the water and lower sulphate concentrations. In this process, SRB reduce metal sulphates to insoluble metal sulphides as part of their metabolic activity. These sulfides precipitate, removing the metals from the water. In addition, a number of species of SRB are able to reduce some otherwise hard to handle metals, (e.g., reducing uraniu