Explain the specific functional advantage of a geomembrane over compacted clay as a primary barrier in a landfill liner system, considering permeability.

A geomembrane, typically a synthetic polymer sheet like High-Density Polyethylene (HDPE), offers a significant functional advantage over compacted clay as a primary barrier in a landfill liner system due to its vastly superior, extremely low permeability. Permeability is a fundamental material property that quantifies its ability to allow fluids, such as landfill leachate, to pass through it, commonly expressed as hydraulic conductivity. A geomembrane exhibits hydraulic con....