Superior Oil Co Sia is a superfund site located at Hwy 460, Crossville, IL 62827. The Environmental Protection Agency (EPA) identifies sites such as Superior Oil Co Sia 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. Superior Oil Co Sia is currently registered as an Archived superfund site by the EPA and does not require any clean up action or further investigation at this time.