Leachate in the environment – Educador

Worm farms with the capacity to collect leachate.

Leachate, also known as “percolated liquid”, is a malodorous and generally dark-colored liquid, originating from organic waste decomposition processes. As its composition varies according to the type of organic matter that originated it, it can cause irreparable damage to living beings, especially those that live or feed in landfills. It can also contaminate groundwater and other water resources; or bring disease.

The leachate problem could be considerably overcome if some changes were made to the way we dispose of waste from our homes and schools. Send batteries to manufacturers, instead of throwing them in general trash; separate disposable waste and can donate it to cooperatives or collectors; send used oil to collection points or make soap; and composting organic waste, or building worm farms, are some measures that could be adopted in our daily lives.

This information can be shared with your students, for example, by adopting the use of worm farms that separate the leachate. In addition to allowing the decomposition of organic waste, they allow the manufacture of an excellent natural fertilizer and can also produce a type of percolated liquid that serves as a fertilizer for plants, gardens and soil, as it only contains food remains, and not battery components or even feces, as in landfill leachate, for example.

This device is quite simple to make and can be adopted throughout the school, even as a way of demonstrating to students, parents and staff that sustainable actions are not always difficult and/or expensive. The humus and slurry from these can be used, for example, in the school garden, or even sold, in order to supplement the income of the school, families or even to organize guided visits or parties at the institution.

To build this, the first step is to purchase plastic drums, or even large waste baskets. A hole must be made in this, approximately 5 cm above the base, attaching a filter tap to that location.

Fill the container with gravel or pieces of brick, up to the limit of the tap. With a shading screen, isolate this first layer using wire, if necessary.

After these procedures, follow the steps explained in the text Worm Farm. As this is a larger project, the number of worms must also be greater.

Approximately one week later, depending on the quantity and type of material deposited in the worm farm, the slurry can now be removed from the tap.

Such a sample can be used to analyze:

– its combustion power and feasibility of being used as biogas to generate energy in thermoelectric plants;
– its benefits for plants, when adding it to one and leaving another, of the same species, without it;
– the resistance of earthworms to it, among others.

Don’t stop now… There’s more after the advertising 😉

By Mariana Araguaia
Graduated in Biology