Minnesota plans rewrite of rules for copper-nickel mining near popular wilderness

ST. PAUL, Minn. (AP) — Minnesota regulators have concluded that state rules governing where copper-nickel mines can be built are insufficient to protect the Boundary Waters Canoe Area Wilderness from noise and light pollution. The decision Wednesday creates another potential obstacle to the proposed Twin Metals mine. To address the potential noise and light impacts of mining, Minnesota Public Radio reports, the DNR will write new rules to expand an existing buffer to provide a greater setback from the Boundary Waters. DNR officials say the rulemaking would take around 18 to 24 months. The process would help determine how large the buffer needs to be,