Although most mining companies don’t make public the compensation packages they give their middle management personnel, such incentives are known to be a common practice in the industry. Thus, using the information provided by the two companies that do report them, Newmont Goldcorp (NYSE: NEM, TSX: NGT) and AngloGold Ashanti (JSE:ANG, NYSE:AU), the authors of the study found that some schemes are equivalent, in financial terms, to an equity payment plus a put option.

The number of tailings dam failures has doubled in recent years from 8 in the period 1999–2003 to 16 in 2014–2018

“So the bonus is highly leveraged. Like investment bankers, the person stands to gain a lot if his/her performance is above target, but loses little, if it falls below target,” the study reads. “Year after year, managers keep taking risks with a low probability of occurrence but with potentially catastrophic consequences. These risks are compounded by shortages of experienced staff due to the cyclic nature of the industry and the retirement of the baby-boomer generation.”

Authors Margaret Armstrong, Renato Petterd and Carlos Petterd connected their observations to those in earlier research papers that analyzed certain cases of tailings dams failures and found that either production was increased or costs were significantly reduced in the years leading to the accidents.

The academics report that, for example, prior to the collapse of the tailings facility at the gold and copper Mount Polley mine in British Columbia in August 2014, which resulted in 24 million cubic meters of contaminated sludge and mine waste going into nearby lakes and rivers, Canada’s Imperial Metals (TSX: III) had grown its production by 23% in Q2-2014 from the previous quarter.

Boliden Apirsa, on the other hand, had flat revenues from 1995 to 1997, just before the tailings dam crashed at the Los Frailes lead and zinc mine in Aznalcóllar, Spain, in April 1998. But capital expenditures doubled during this period from $55.4 million to $112.3 million and operating income increased spectacularly from $2.3 million to $84.9 million. “So production costs must have dropped significantly over the period.”

In Brazil, production at Vale’s (NYSE:VALE) Samarco iron ore mine had increased by almost 40% in the five quarters just before the accident there in 2015, which killed 19 people and became the country’s worst-ever environmental disaster. Similarly, at the Paraopeba subsection of the Southern System where the Corrego do Feijão dam was located, production was risen by 12% in the eight years before the Brumardinho catastrophe where almost 300 people died.

“The next question we asked ourselves was: Had an extra tailings dam been constructed to handle this additional quantity of rejects, or was it being pumped into existing tailings facilities? Alternatively, had filter presses or high capacity thickening been introduced to reduce the quantity of water?”, the authors of the paper ask.

After reviewing Vale’s quarterly reports for investors, which list all the major projects in progress, they found that there is no mention of building a new tailings dam or of filter presses. “This means that the existing ones had to cope with the waste from the extra production.”

Off the hook

Except for $42.5 million for the initial clean-up, the paper in Resources Policy highlights the fact that Boliden Apirsa succeeded in avoiding paying for the pollution caused by the tailings dam breach.

“Boliden’s legal team and expert witnesses convinced a Spanish court of law that the tailings dam failure was due to geotechnical problems, thereby transferring the responsibility to the companies that had designed and built the dam. An epic legal battle ensued in which the Spanish Ministry of the Environment and the local government of Andalusia attempted to get Boliden to pay for the damage, but failed due to loopholes in the Spanish legal system,” the document reads.

In the case of the Mount Polley mine, Armstrong and her colleagues bring to the forefront the fact that the Independent Expert Engineering Investigation and Review Panel established after the accident found that the failure was caused by the design, which did not take into account the complexity of the sub-glacial and pre-glacial geological environment associated with the Perimeter Embankment foundation.

This has meant that no one has been held responsible for the disaster and, on top of this, the 3-year deadline to lay charges under British Columbia laws passed in 2017, while there is only one year left to lay charges under federal environmental and fisheries law.

The authors of the study refrained from commenting on the legal proceedings involving Vale’s tailings dam failures as they are still in progress.

In their recommendations of what would be needed to stop tailings dam failures, the researchers suggest, besides changes in the processing technology and wider adoption of the Mining Association of Canada’s guidelines issued in 2017, heavier fines and penalties.