Question

What do you mean by land filling? Explain briefly.

Answer 1

• Landfills are a vital component of any well-designed Solid Waste Management system. Landfilling is a process of dumping solid waste in a scientifically designated land area, spreading waste in thin layers, compacting it to the smallest practicable volume and covering with soil on a daily basis. Methanerich biogas is produced due to anaerobic decomposition of organic matter in solid waste.
•  Landfills range in type from uncontrolled open dumps to secure sanitary landfills. Uncontrolled, open dumps are not a sound practice, but controlled dumps and sanitary landfills can provide effective disposal of a city's solid waste in accordance with appropriate local health and environmental standards.
  A modern landfill consists of,
  1. Landfill liner is made up of multiple, engineered layers of geosynthetic and natural soil materials underlying the disposal area. It prevents rainfall and other liquids that come in contact with the waste from escaping into the environment. It also restricts the underground migration of landfill gases.

2. Clay cap is a vegetated cover placed over the landfill at completion of filling, consisting of geosynthetic and natural soil materials. It prevents the escape of landfill gases to the air and restricts the infiltration of rain into the landfill.

3. Gas recovery system consists of extraction wells and piping that remove methane and other decomposition gases from the landfill for proper destruction and reuse.

4. Leachate management system consists of pipes placed beneath the waste (and above the liner system) that remove leachate from the landfill for proper treatment. Leachate is described as liquid that has percolated through the layers of waste material and is composed of liquids that originate from a number of sources, including precipitation, groundwater, initial moisture storage, and reactions associated with decomposition of waste materials.

5. Monitoring system that promptly detects the releases to air, surface water and groundwater resources to ensure protection of public health, safety and the environment.