Geosynthetic Clay Liners (GCLs) are composite materials used primarily for environmental protection and containment. They consist of a layer of natural clay sandwiched between two geotextiles or geomembranes. GCLs are designed to provide a low permeability barrier, making them effective for applications such as landfill liners, pond liners, and containment systems for hazardous waste. These liners are lightweight and easy to install, which reduces construction time and costs. GCLs can also be used in various soil conditions and are often preferred for their durability and resistance to chemical degradation. Their effectiveness in preventing fluid migration makes them a valuable tool in environmental engineering.