After the catastrophic rupture of a mine-tailings dam in Brazil last week, leaving behind at least 110 dead , 238 missing and an environmental disaster of epic proportions, the police were quick to arrest five people who had been responsible for inspecting the dam and who most recently proclaimed it “stable.” Certainly they had erred, and courts will decide whether they did so criminally. But rounding up the usual suspects does not begin to address responsibility for a disaster of this scale and a danger many mining communities face around the world.

Tailings are the wet waste from mining operations, often laced with toxic chemicals. At thousands of mines around the world, millions of tons of the muck accumulate behind dams. The most common type of dam — and the cheapest to build — is known as “upstream,” made by piling up thick sludge and raising the height of the dam as the pond grows. At the mine where the accident occurred in southeastern Brazil, owned by the giant mining company Vale, the dam was 28 stories high.

The danger posed by tailings dams is well known. Three years ago another upstream dam in the same Brazilian state, Minas Gerais, and co-owned by Vale and Australia’s BHP Group, collapsed, killing 19 people. The muck from that mine flowed 400 miles to the Atlantic Ocean. Other dams have collapsed in many countries around the world, and while the overall number of failures each year has been declining, the occurrence of major collapses has increased. According to the database World Mine Tailings Failures, there were 46 “serious” or “very serious” collapses — such as those in Brazil — between 1998 and 2017.

One reason is increased rainfall because of climate change, which can erode a dam wall years after the tailings pool is no longer in use. One study found that heavy rain was cited as a contributor to a quarter of global dam failures. Given that there are thousands of tailings dams around the world, and that mining companies generate ever more waste — they produced 8.5 billion metric tons in 2017, more than double the amount in 2000, according to an Australian researcher — the dams pose a danger that arresting a few workers won’t address.