The Brazilian state of Minas Gerais, where a burst dam at a Vale iron mine near the town of Brumadinho triggered one of Brazil’s greatest environmental disasters has passed a law banning the construction of upstream dams.

The law, passed on Monday by Governor Romeu Zema following approval of the state’s legislative assembly last week, follows a nationwide ban on the dams. A similar bill was proposed to the state government in 2016, following the collapse of a dam at the Samarco project, owned by Vale and BHP, which killed 19 people, but the proposal was defeated.

Under the new law, mining companies will be prohibited from building upstream dams in the state, and will have three years to decommission existing structures. The law also tightens the permitting requirements for new mining projects, with new operations needing three types of permit ahead of construction, and clarifies that mining companies are solely responsible for disruptions and accidents at their operations.

Should an accident similar to the Brumadinho disaster take place, the mining companies responsible could face a fine up to 1,000 times greater than other fines for compliance violations. In such circumstances, the offending companies are required to allocate half of the fined sum to communities affected by the disaster.

“In three years, as has been said here, no dam built upstream will exist anymore in Minas Gerais and, I am sure, no successor of mine is going to face a tragedy like that which occurred a month ago,” said Zema. “From now on, I can say that we put an end to this kind of fact that really cannot happen anymore.

“Let Brumadinho be the last.”

The collapse of the dam saw 12 million cubic metres of mining waste released into Brumadinho and the surrounding area, killing 169 people. A further 141 remain missing, although a month on from the disaster there is little hope that any will be rescued.

Last week, rescue workers identified a warehouse buried beneath mud and waste, but were sceptical that they could reach the bodies, let alone rescue any victims alive.

While Vale has made a number of commitments to the relief effort, including offering reparations of $3,000 to each adult affected by the disaster, the Brazilian Government has pressed for a number of company employees to be charged over their role in the disaster.

Eight individuals, including two company executives, were arrested earlier this month, and last week the government targeted a senior executive for the first time, director of ferrous metals Gerd Peter Poppinga.

“Poppinga represented a risk to the public order and his freedom could hurt the enforcement of criminal law,” said prosecutor Gustavo Oliveira in the arrest warrant filed earlier this month.

Poppinga was also a board member of the Samarco project at the time of the 2016 incident, and is currently facing charges for his role in the accident.