As the city grew and the standard of living of the inhabitants improved, the amount of municipal waste increased. It was necessary to start taking the waste somewhere in a centralised manner.

It usually ended up in hard-to-exploit areas, such as marshes or alluvial land. The Vuosaari landfill was founded in a field called Tavastängarna, which was no longer cultivated.

Municipal waste was received at the Vuosaari landfill for 22 years (1966–1988). The landfill contains 3.4 million tonnes of unsorted waste.

The waste decomposes very slowly in oxygen-free conditions and hardly changes its appearance for decades.

The old landfill was governed by the law of the jungle, where the fast eat the slow. Tapio Maikkola 1979, National Board of Antiquities

Back in the day, the leachate from the waste mountain flowed into nearby ditches, from where it continued to the bays of Porslahti and Porvarinlahti. The ditches of the landfill site were provided with drains in the early 1980s, and leachate has not been a burden on nature since then. The Vuosaari landfill was closed in 1988, after which it was covered with a thin layer of land.

Organic decomposing waste produces climate-heating landfill gases, such as smelly methane. A gas collection system was built in the ground layer of the landfill site. The collection of gas was an important climate action by the City of Helsinki and also reduced the risk to people and the environment. The rehabilitation of the Vuosaari landfill included the construction of a new, more efficient gas collection system. The rehabilitation process to render the landfill harmless to the environment was carried out between 2012 and 2020.

In addition to waste, contaminated soil from construction sites in Helsinki was later stored at Vuosaarenhuippu. The soil fill site next to Satamakaari has been made environmentally safe.

Soil is spread onto a bentonite mat during landfill rehabilitation. Tomi Muukkonen
Surplus soil has been used as new topsoil for landfill rehabilitation. Tomi Muukkonen 2019

The Vuosaarenhuippu depot area is used for intermediate storage of soil and rocks suitable for recycling. The former landfill site has heavy traffic bringing and retrieving soil and rocks for utilisation.