16 July 2019
Cobriza, Peru: another significant tailings dam failure
Another significant tailings dam failure occurred at Cobriza in Peru on 10th July 2019. Cobriza is a copper mine – interestingly, some reports indicate that “the concentrator was operated at a rate quite below its capacity due to lack of mine ore and lately (2016 and 2017) due to lack of capacity in the tailings dam“. The plant is also subject to a privatisation, originally planned for 2018 but now expected this year. The site is at -12.58, -74.37 if you want to take a look.
The failure is quite clear in Planet Labs images of the site, collected over the last few days. To get an understanding of the site, take a look at this Google Earth image of the mine and the tailings facilities. The view is taken looking towards the west:-
The two tailings facilities are larger than they might first appear – the one on the right (which failed last week) is about 500 metres x 300 metres.
This is a Planet Labs image from 9th July 2019, before the failure, with north at the top of the image:-
I have highlighted two locations. The yellow arrow indicates the tailings facility that underwent failure last week. The red arrow indicates the bed of the river downstream of the site – note that the water was clear when the image was collected.
The image below, dated 12th July 2019, shows the mine after the failure:-
The change in the geometry of the tailings facility is apparent, marking the site of the failure. The water downstream is obviously contaminated. Note that the water upstream of the mine (bottom right side of the image) is still clear (i.e. unpolluted).
I have provided further detail in the Planet Labs image below:-
In this image I have highlighted the breach of the tailings dam with the yellow arrow. The orange arrow indicates clear tailings contamination of the bench around the mine facilities. The red arrow marks the point at which the tailings are entering the channel – note the distinct change in the water colour.
The escape of the tailings has generated a serious pollution incident in the Rio Mantaro. There are fears that a stretch of the river extending for 375 km has been contaminated with cyanide. This video on Youtube reportedly shows the contamination in the Rio Mantaro:-
Reference and acknowledgement
Thanks to David Reid for spotting this one.
Planet Team (2019). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https://www.planet.com/