Our Leachate Treatment System

An engineered wetland treats the leachate coming from our landfill.  Leachate is created when rainwater runs through solid waste and leaches out to form a liquid.  Prior to 2009, our leachate was being treated through a natural marshland.  Constructed and natural wetlands are used to clean polluted waters through a variety of physical, chemical and biological processes. These wetlands can remove nutrients, metals and other pollutants from the wastewater before it is put back into the natural environment. All collected surface and ground water is filtered through the leachate treatment system. Different cells contain a mixture of sand, woodchips and plants that treat the leachate.

How It Works

To construct the wetland, a site is dug out and walls are built with plywood. A huge liner is installed along with a pump and a series of pipes to gather the ground and surface water that comes from the landfill.

Layers of sand and wood chips are spread over the site.  The leachate is pumped through the different parts of the wetland. Each section of the wetland helps to make the water cleaner.

The Final Touches

Cattails are planted directly into the sand. The cattails are an important part of the treatment of water. They absorb nutrients and help filter toxins from the leachate. Once the leachate has been treated and is cleaner, safer water, it is drained into the natural marshland.

What Contributes to Leachate?

The construction of this Engineered Wetland system to treat Leachate was important in the approval of our landfill to expand its operating license to 40 years.  Making sure that materials such as hazardous waste, drywall and even food waste are kept out of the landfill helps to lower the toxicity of the leachate.  Sorting our garbage carefully and keeping these materials out of the landfill help to create a more environmentally sustainable landfill.