Balclutha's Mt Cooee landfill is receiving a new natural liner which aims to prevent toxic leaching.
Wasteco is behind the project, which aims to make the site more environmentally friendly.
Irrigation ditches were dug at the base of the landfill face, ahead of the final step of laying down the geo-synthetic fibre.
Project foreman Dave Hannan says this natural layer will stop the landfill from polluting the Clutha River.
He says the material is a reinforced composite combining two durable outer layers with a core of sodium bentonite clay, which expands to create a hydraulic barrier.
Hannan says the last touch will be planting a toi tois and flaxes on a layer of soil.
It's one of the final stages in an effort to prevent waste from the landfill from spreading into the Clutha River.
