The collapse two weeks ago unleashed an avalanche of mud that engulfed nearby buildings and farms, killing an estimated 300 people in Brazil’s deadliest mining disaster.
As evidence mounted that Vale missed warnings of trouble at the dam in the town of Brumadinho, pressure has risen on the firm and other mining companies to bolster safety measures to avoid a recurrence.
Vale shares were down 1.9 percent in morning trading to an 11-month low of 40.87 reais. ArcelorMittal shares dropped nearly 5 percent at 19.26 euros. Another dam, also used to store the muddy mining detritus known as tailings and co-owned by Vale and BHP Group, had collapsed in 2015, killing 19 people and wreaking massive environmental damage.
Vale said Brazil’s mining agency ordered the evacuation of about 500 people from a dam area at its Gongo Soco mine on Friday as a preventive measure after engineering consultancy Walm said a certificate guaranteeing stability conditions had not been issued for the dam.