Solid Waste Terminology

Sanitary landfill
A state-approved and designated area of land where natural conditions and man-made modifications produce an environmentally safe location for disposing solid wastes.

Municipal solid waste
The type of waste generated by people in their homes and work, as well as non-hazardous materials discarded from commercial and institutional businesses.

Best available technology (BAT)
An acronym for environmental engineering practices that utilize the latest technology.

Subtitle D regulations
Refers to the minimum environmental standards enacted by the federal government. Each state has the responsibility to apply these standards for the treatment and disposal of solid waste in landfills.

Cells
A series of areas designed and prepared to accept waste.

Working face
The area in a cell where waste is disposed of at a given time. 

Tipping fee
A monetary charge placed on the acceptance of solid waste at a landfill, transfer station or other facility. The fee is determined by weighing the waste load of each truck at the gate, and it is applied on a "per ton" basis.

Methane gas
A by-product of landfills as waste decomposes. Methane gas consists mostly of methane and carbon dioxide. When extracted and processed, it can be used as a source of clean energy.

Leachate
Precipitation or liquid that falls on the landfill or comes into contact with the solid waste.

Leachate collection system
A series of pipes embedded in the drainage layer at the bottom of a landfill. It collects any leachate that travels through the waste. The leachate is pumped out of the system and treated.

Surface water control system
A series of channels to collect and transport rainwater off of a landfill's cap system and slopes to a sediment pond where the sediment settles before the water runs off site.

Ground water monitoring wells
Wells placed around the perimeter of a landfill. They are used to monitor ground water for potential migration of contaminants.

Re-compacted clay and flexible membrane liners
Dense clay, compacted with construction equipment to be used as a protective layer in a landfill cell.

Flexible membrane liners
A high density polyethylene (HDPE) plastic liner, 60 ml thick, constructed on the bottom and sides of the landfill cell to prevent the release of contaminants to the enviroment.

Final cap system
A multi-layered system consisting of vegetation, a soil layer, a drainage layer and a barrier layer. Capping prevents infiltration of rainwater into landfill cells and covers a landfill for aesthetic reasons.