16 April 2019
Planet Labs Skysat image of the Hindalco tailings failure
Posted by Dave Petley
Planet Labs Skysat image of the Hindalco tailings failure
Planet Labs have successfully acquired a high resolution SkySat image of the Hindalco Tailings failure in Muri, India, which occurred last week. It is interesting to compare this with the pre-failure imagery. This is a Google Earth image of the site, collected on 4th April 2018 – i.e. almost exactly one year before the collapse:-
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In comparison, this is the Planet Labs Skysat image of the site after the collapse:-
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Whilst this is a more detailed view of the area that failed:-
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The failure appears to have occurred in the retaining structure on the west side, allowing tailings to move to the west and to a lesser degree to the south. Note the large rear scarp of the landslide. In this case the mobility of the tailings has been quite limited, presumably because they are comparatively dry?
A key task will now be to contain the waste prior to the monsoon to prevent larger-scale contamination of the area. At the moment the affected area is quite limited.
Meanwhile, the Jharkhand State Pollution Control Board has cancelled the consent to operate of the works at Hindalco. Interestingly, there also reports that the retaining wall was designed by IIT Mumbai and IIT Roorkee, who are now under investigation. A panel has been convened to understand the causes of the failure.
Reference and acknowledgement
Planet Team (2019). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA.
Thanks to Robert Simmon for help in acquiring the Skysat image.
The photos suggest there may have been mine waste (rock) trucked in along temporary roads from the north and deposited atop the tailings in this area.
It’s obvious from the historical satellite imagery that the mine began stacking waste rock on top of the tailings impound beginning in 2014-2015. This artificial surcharge loading likely has led to the failure. Needless to say that the TSF was never designed for the application of waste rock storage.