He won the Goldman Environmental Prize in 2017 after leading a successful legal challenge against the company operating a cement kiln that was incinerating hazardous waste near his farm.

[1][4] Air pollution from nearby factories has affected people and wildlife in the region for a long time.

[4] The region Macerl lived in in central Slovenia had a history with air pollution from emissions from industrial towns.

[1] The European Union introduced incentives in recent years for companies willing to incinerate energy sources such as "medical waste, old tires, and other industrial residue", in place of coal.

[3][4] The Commission ruled in favor of the residents of the town in 2015, and Lafarge was forced to stop cement production at the plant.