ST. PAUL, Minn. (AP) _ Some Minnesota lawmakers want to tighten rules for the safe storage of toxic waste from metal mining.

Reports say legislators are proposing new regulations as two proposed copper-nickel mines in northern Minnesota have raised concerns that they'll pollute Lake Superior and Boundary Waters Canoe Area Wilderness waters.

Tainted water and byproducts from mining are usually stored in big ponds or dams.
Republican Sen. Paul Anderson says dam failures have been increasing across the region. He says the Legislature needs to address the issue to prevent storage failures that could cause serious water pollution.

The new rules would require metal mining storage structure designs to be approved by an independent group of engineers. Companies would also have to create plans for managing the dams and undergo annual inspections.

Lawmakers will consider the rules in the fall.