Subsurface Surveying of Water for Build-up of Sludge or Silt

We operate 47 sites where mine water is pumped to a treatment scheme before being returned to a water course. Raw mine water is generally acidic and in some cases it is chemically dosed. The main contaminant in raw mine water is dissolved iron. The dissolved iron forms an iron oxide known as ochre that precipitates on exposure to atmospheric oxygen. Ochre builds up in the settlement ponds & reed beds. The Coal Authority removes the ochre on a periodic basis. The measurement of ochre in settlement ponds is required...