The Berkeley Pit in Butte, Montana, has been a source of environmental concern for decades, as its waters—highly acidic and teeming with toxins—have seeped into the surrounding area. But today ...

The Berkeley Pit, however, has a much richer concentration of rare earths in solution and a higher volume of water and is expected to produce 40 tons a year. Dr. Ziemkiewicz believes this process ...

The Department of Defense has encouraged the Montana Mining Association and West Virginia University to pursue funding that could help the Berkeley Pit become a source of rare earth elements.