Mine-waste dams around the world have drawn new scrutiny after a collapse in Brazil this year killed hundreds
EMBARRASS, Minn.—An earthen dam is set to rise behind the trees of Dan Ehman’s 120 woodland acres in northeastern Minnesota’s Iron Range, a region with close ties to mining for more than a century.
The planned dam, designed to hold back hundreds of millions of tons of mining waste, will be similar in structure and height—soaring 250 feet above Mr. Ehman’s century-old log cabin—to one in Brazil that burst in January, killing 270 in a tsunami of sludge.
That disaster, the deadliest of its type in half a century, has upended the global mining industry. The world’s biggest mining giants have spent months and millions of dollars re-evaluating their dams. Institutional investors are scrubbing their portfolios, looking for companies with risky structures—and helping to publicize potential stability issues. And environmentalists are getting new support from residents, some of whom are learning for the first time about the potential dangers of the dams in their communities. Continue Reading →