What are Landfills and solid waste?

Answer:

A landfill is a location designed for the systematic longterm storage of waste under conditions that will prevent the contamination of air and water.

A landfill may be designed for the storage of inert waste, sanitary waste (rubbissh) or hazardous industrial waste. The control measures become more stringent as the hazards associated with the wastes go up.

Typically a landfill consists of several cells, each of which is filled and completed before the next cell is used.

A cell is pit fitted with under drain piping and an impervious liner.

Waste is put into the cell and periodically covered with clay.

When the cell is full, a final covering of clay is applied, then a layer of topsoil is added to allow grass to be grown on he surface

Monitoring systems to check for water pollution or methane generation may be present.
I think that you are probably mistaking the Word landgfill for the Word 'landfill' and a landfill is a low area of land that is built up from deposits of solid refuse in layers covered by soil.
Landfill is the name given to garbage dumps, rubbish tips etc. Typically the local authority finds what they hope is a suitable site, perhaps an old quarry, and then all the garbage collected from residents is dumped there.
A low area that has been filled in
.a low area of land that is built up from deposits of solid refuse in layers covered by soil.