It is estimated that between 7 and 7.5 million metric tons of steel slag is produced each year in the United States. Even though it can be recycled, slag is frequently sent to landfills for disposal. Slag is a byproduct of steel production and is comprised of a complex solution of silicates and oxides that congeals upon cooling. Slag is produced during the separation of the molten steel from impurities in a blast furnace. Slag is highly alkaline, with a pH between 9.5 and 11, and does not retain enough water for plants to germinate.
The procedure for cleaning up a site where slag has been disposed of can vary depending on many factors. It can be extremely costly, and some of these sites end up labeled as a Superfund, due to their high environmental threat levels.
- Environmental assessment
- Removal of soil and debris
- Disposing in a hazardous waste facility
- Capping contaminated sediments with clean sediments
- Erosion protection
- Habitat restoration and redevelopment