Cleveland-Cliffs Minorca Mine leaked wastewater, construction runoff and tailings materials into nearly half an acre, including a nearby wetland, in May and June 2023, according to a Minnesota Pollution Control Agency (MPCA) enforcement investigation. The leak, which caused nuisance conditions in the wetland, was the result of inadequate operation and maintenance of the tailings basin pipeline at the company’s facility in Virginia, Minnesota.
The investigation also confirmed unpermitted runoff from construction activities on the tailings basin road impacted the same wetland in June 2023. The investigation found that about 11,500 cubic feet of tailings materials were leaked.
In addition to paying the $16,750 civil penalty, Cleveland-Cliffs has completed a series of corrective actions including:
- Updating its tailings pipeline inspection and maintenance plan to include semi-annual pipe wall thickness testing.
- Developing an environmental screening checklist as guidance to address environmental requirements prior to beginning construction or maintenance projects.
MPCA rules and regulations are designed to protect human health and the environment by limiting pollution emissions and discharges from facilities. When companies do not fully comply with regulatory requirements, the resulting pollution can be harmful to people and the environment.
When calculating penalties, the MPCA considers how seriously the violations affected or could have affected the environment, and whether they were first-time or repeat violations. The agency also attempts to recover the economic benefit the company gained by failing to comply with environmental laws in a timely manner.