A $5 million visitor center for the Sanford Underground Research Facility at Lead is on track to open by June.

The Black Hills Pioneer reports work included the installation of 22 steel support piers that go down 100 feet to the bedrock and keep the building stable because it's perched near the edge of the old Open Cut surface mine.

The federally supported lab that's nearly a mile underground in the former Homestake Gold Mine is home to researchers who are studying complex subjects such as nuclear reactions within stars. They're also interested in dark matter, an elusive substance that scientists believe makes up about one-fourth of the universe.

The 8,000 square-foot visitor center will showcase Lead's history and offer educational programs about the lab's science projects.

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