All aspects of mine tailings facilities are now under intense scrutiny
The global reaction to the Brumadinho tailings dam disaster in January 2019 has brought all aspects of mine tailings facilities under intense scrutiny. This is especially true for as-built surveys of tailings dams. The technical report on the Brumadinho dam failure documents the almost complete lack of as-built surveys of the construction and raising of the failed dam.
The Brumadinho report shows the importance of frequent, accurate, time-stamped mine site surveys
This lack of as-built surveys at Brumadinho has emphasised the crucial importance of frequent, accurate, time-stamped, site wide surveying to confirm that mine construction conforms to the engineering designs. Without regular time stamped, as-built surveys it is difficult to impossible to conduct comprehensive, independent, safety reviews of dams and other earthworks structures.
Many mines have incomplete and inaccurate survey data
Many mine tailings engineers currently rely on survey reports from multiple sources with unknown or uncertain accuracy and unknown survey dates and times to build a comprehensive view of their TSF. They believe this process provides them with sufficient information to allow operations and planning to maximize long term safety and stability of the TSF.
The extent to which errors or omissions in the current survey data impacts the ability to verify that the TSF meets it’s design and operation criteria is often underestimated. Recent dam failure “postmortems” have shown that at some mines consolidating survey data into a single comprehensive “story” is often difficult at best.