By: Stephen M. Johnson

Stephen M. Johnson — Fri, 21 Feb 2020 23:18:58 +0000

The tailings had an actual pond on top when it failed! Plus it is in an obvious catchment basin. I wrote a bit on it in LinkedIN. Construction, filling and use aside that facility would be a violation if it were a landfill. Duckponds are not allowed. Who knows what kind of infiltration gallery developed…internal saturated zones…high pore pressures, overloaded segments and likely perched water tables backed up against the retention berm. These are all common geotechnical issues. Uncommon ones might include authigenic clays growing within the mix. My experience with geotechnical engineering theory for civil structures did not point to geochemistry or mineralogy…only soil mechanics and hydro. All efforts to maintain and enlarge the tailings facility had to fight water perched upon what triggered Vale’s last failure…slimes getting into the tailings.

Comments on: Internal probe confirms Vale knew Brumadinho dam was unsafe

By: Stephen M. Johnson