Minnesota’s Environment

Sulfide mining produces toxic waste that could irreversibly damage Minnesota’s fragile lakes, rivers and natural resources.

This is not our grandparents’ iron mining — sulfide mining has never been done in Minnesota. While iron mines have significant environmental challenges of their own, the sulfuric acid that is produced with sulfide mining makes it particularly difficult to avoid polluting nearby lakes, streams and ground water.

Acid Mine Drainage

When water and air mix with the waste from iron mining, rust is produced. But when the same process happens with sulfide mining, sulfuric acid is created. When this acid dissolves rock and leaches out toxic heavy metals, the substance is commonly called “Acid Mine Drainage.”

When water and air mix with iron mining waste, you get rust. With sulfide mining, sulfuric acid is produced.

Acid Mine Drainage has devastated water bodies in many states where this type of mining has occurred. It kills fish, wildlife and plants, leaving lakes, rivers and streams devoid of most living creatures.

Effects on people, water and wildlife

Humans
Mining by-products such as arsenic, manganese and thallium, have been shown in high levels to increase the risk of cancer and other illnesses in humans. Because mining takes place below the water table, it’s easy for contamination to leach out of the mine into groundwater, threatening drinking water supplies and health. More about risks to human health… More