Iron is one of the most abundant elements in rocks and soils, and one of the most common problems in groundwater supplies. Rainwater seeping through soils and bedrock dissolves iron and carries it to wells and springs. In deep groundwater systems that lack oxygen, iron occurs as dissolved ferrous ion and the water is clear. Under oxidizing conditions such as in shallow groundwater systems or where the water is exposed to air at a tap or faucet, however, iron converts to a ferric form when it combines with oxygen to form reddish-brown rust particles. In addition to natural sources, elevated iron concentrations in water are also associated with acid drainage from coal mining.
Information Circular 13
Digital Object Identifier (DOI)
Fisher, R. Stephen and Davidson, Bart, "Groundwater Quality in Kentucky: Iron" (2007). Kentucky Geological Survey Information Circular. 11.