It was when waste was to be moved from Skultuna to Rörfors outside Laxå that the discovery was made, which Expressen was the first to tell.
- We got suspicions that they drove waste between Skultuna and Laxå, and therefore we contacted Laxå, says Marianne Lidman Hägnesten, director of the environmental and health protection administration in the city of Västerås.
According to Marianne Lidman Hägnesten, masses from Skultuna were to be used as filling masses in Laxå, but the waste was first examined there.
Then high levels of the metals zinc and copper were discovered.
At the same time, the external consultant was asked to carry out a sampling at NMT's facility in Skultuna.
"Hazardous waste"
At Skultunatippen, elevated levels of lead, zinc and copper were discovered.
The levels of copper exceeded the value of what is described as "hazardous waste".
According to the City of Västerås, NMT has not informed them that high levels of metal have been found at the facility in Skultuna, and therefore the company has reported to the police.
Three have been arrested
The City of Västerås has previously reported the company to the police for the fires that occurred in the waste masses at the facility in Skultuna in February and March last year.
Earlier this week, three people with connections to the company were arrested on suspicion of serious environmental crimes around the country.
One is also suspected of a serious money laundering offense.
District Attorney Kristina Persson did not want to comment on exactly where the suspected environmental crimes should have been committed, but says that it is in different places in Central Sweden.
However, she confirms to SVT that one of the people who has now been arrested is suspected of a crime in Skultuna.