Once a landfill is full, it is capped with another liner made of synthetic plastic. That liner is covered with at least two feet of soil, then vegetation is planted. The site continues to be monitored for at least 30 years to ensure the surrounding environment is safe from contamination.
Landfill capping helps to buffer humans and the environment from a landfill’s contaminants, limits migration of debris and creates an opportunity for the area to be transformed into parks and open spaces.