A sanitary landfill is a multidisciplinary engineering project. The structure includes soil waterproofing to protect groundwater, as well as the proper coverage of waste, and it can go further by recovering collected waste, as in the Orizon Ecoparks.
The sanitary landfill is a response to the solid waste management challenges in Brazil, which in 2024 had 41% of municipal solid waste (MSW) improperly disposed of, causing not only major environmental impacts but also missing opportunities to generate new solutions from these materials, through recycling, composting, biogas, biomethane, and other alternatives.
The implementation of these spaces is essential for responsible waste management in Brazil, governed by the National Solid Waste Policy (PNRS), Law No. 12.305 of August 2, 2010. This law sets out specific rules that encourage and regulate sanitary landfills, such as:
- The Ban and Deadline for the Elimination of Dumps (Art. 54): the law prohibits the final disposal of solid waste in open dumps, requiring that waste be treated and reused whenever possible before final disposal;
- Environmentally Appropriate Final Disposal: sanitary landfills are considered the last step in the waste management process, which should prioritize reduction, reuse, and recycling. The infrastructure must also include gas control, leachate management, and protection of soil and groundwater;
- Shared Responsibility: the law establishes shared responsibility throughout the product life cycle, involving the public sector, private companies, and society;
- Waste Management Plans: municipalities are required to prepare Municipal Integrated Solid Waste Management Plans (PMGIRS), which must include guidelines for implementing and operating sanitary landfills, including waste destination and remediation of degraded areas;
- Technology and Sustainability: the policy encourages the adoption of clean technologies, waste reduction, and energy recovery through biogas capture.
How a sanitary landfill works
The sanitary landfill is an engineered space prepared with soil impermeabilization, greenhouse gas capture systems, and leachate (liquid resulting from material decomposition) treatment.
This infrastructure is built away from urban centers, occupying large areas. It not only disposes of waste while protecting the environment, but also prevents discomfort to the population, such as bad odors and exposure to hazardous components, and ensures that fauna and flora are not affected.
The sanitary landfill operates through three main processes:
- The base, which includes a compacted clay layer covered with HDPE plastic liner, an impermeable material that prevents waste and its leachate from contaminating the soil and groundwater.
- The operational area, equipped with gas drains that capture greenhouse gases and leachate drainage pipes that direct the liquid to a treatment facility;
- The top, where waste is deposited in layers and eventually covered with a vegetative layer.
Caption: AI-generated image – How a sanitary landfill works.
Ecopark: the evolution of the sanitary landfill
An Ecopark is a modern and integrated solution for solid waste treatment and recovery — a sanitary landfill that uses technologies to implement the circular economy, enabling sorting, reuse, and environmentally appropriate disposal in one location.
In an Ecopark, waste is not only contained to prevent environmental damage but also recovered to generate positive impact.
Its main functions include electricity generation from biogas, production of biomethane (a renewable fuel similar to CNG), composting for organic fertilizer, and automated separation of recyclables.
Non-recyclable and non-compostable waste undergoes processes such as blending to produce RDF (Refuse-Derived Fuel), used as an energy source in industrial kilns and boilers, such as in cement factories. In this way, the Ecopark reduces greenhouse gas emissions, values waste as a resource, and provides a safe, efficient, and sustainable alternative to old open dumps.
