The U.S. Bureau of Land Management (BLM) renewed a pair of mineral leases for Twin Metals Mining near Minnesota’s Boundary Waters Wilderness area. The renewal of the leases is a key step in opening the popular wilderness and recreation area up to copper mining despite heavy opposition from local and national conservation groups.

Twin Metals Mining is a subsidiary of Chile’s Antofagasta that is working to develop a large underground copper-nickel mine near Ely, MN.

The BLM granted the hardrock mineral leases inside the Superior National Forest with the aim of expanding domestic mining of “critical minerals” used in common appliances and products, saying it is beneficial to national security because it reduces foreign imports.

“Mining strategic metals in the United States is beneficial to national security, national and local economies, and job creation,” the Interior Department’s assistant secretary Joe Balash said in a statement.

Reuters reported that Twin Metals must now submit a formal mine plan of operation to the BLM, which will then analyze its potential environmental impacts.

The renewed leases add new conditions, including higher annual royalty payments, project milestones, and additional environmental requirements.

“This lease renewal is a critical step to allow us to present a proposal for our underground mine project,” Kelly Osborne, Twin Metals Mining chief executive officer said in a statement. “It’s very good news for us and for the communities in northeastern Minnesota who look forward to the hundreds of jobs and major economic development this mine will bring.”

The announcement riled conservation groups, who said the Trump administration conducted an insufficient environmental review process leading up to its approval.

The Obama administration in 2016 had implemented a moratorium on new mineral development in the area while it would conduct an extensive environmental impact statement (EIS) analysis to determine whether 234,000 acres of the watershed around Boundary Waters should be withdrawn from mining for up to 20 years.

President Donald Trump reversed course, cancelling the EIS in favor of a less-demanding and faster environmental assessment last January. 

The BLM said it got more than 39,000 comments during the 41 day EA review, which informed its decision, although the majority of those comments were in opposition to allowing mining.

“For more than a decade, Twin Metals Mining has been conducting the largest geological study in Northeastern Minnesota’s history,” the company said in a statement. “With more than $450 million already invested in the project, TMM is committed to developing these resources in an environmentally safe and sustainable manner. TMM will meet and, where possible, exceed all state and federal environmental standards, provide hundreds of jobs for generations of Minnesotans, and generate billions of dollars of environmentally-responsible economic growth in the region.”