Investigation finds Samarco dam failed due to liquefaction

Reuters News
Posted: Aug 29, 2016 2:59 PM

BELO HORIZONTE, Brazil (Reuters) - An investigation launched by Brazilian miner Samarco, and its owners Vale SA and BHP Billiton, into the cause of a dam spill last November found the dam collapsed due to liquefaction, a presentation said on Monday.

Liquefaction is a process whereby a solid material such as sand loses strength and stiffness and behaves more like a liquid. Norbert Morgenstern, a geotechnical engineering professor that presented the results, said liquefaction occurred because sand in the tailings dam was "loose, uncompacted and saturated."

(Reporting by Marta Nogueira; Editing by Alan Crosby)