Madison County Mines is a superfund site located at 401 N Mine Lamotte St, Fredericktown, MO 63645. The Environmental Protection Agency (EPA) identifies sites such as Madison County Mines because they pose or had once posed a potential risk to human health and/or the environment due to contamination by one or more hazardous wastes. Madison County Mines is currently registered as an Active NPL superfund site by the EPA. Because it is on the NPL (National Priorities List), Madison County Mines is considered one of the worst hazardous waste sites identified by the EPA.