CA18/2/1/94

The Coal Authority currently operate 161 individual reed beds providing treatment capacity at 59 mine water treatment sites and 130 settlement ponds at 53 sites. The purpose of the mine water treatment sites is to remove iron that has been mobilised from old mine workings into groundwater. These mine water treatment sites operate by enabling oxidation of the iron, which is then precipitated as iron hydroxide (ochre) and settled in settlement ponds. The effluent from the settlement ponds is then passed through reed beds to polish the water before discharge to local water courses under discharg…