Geosynthetic Clay Liner (GCL) is a sealing material produced by combining natural sodium bentonite clay with two geotextile layers or a combination of a geomembrane and a geotextile layer. When in contact with water, bentonite expands, forming an impermeable barrier. GCLs have been developed as an alternative to traditional compacted clay layers, offering a thinner yet highly effective sealing solution. Due to its excellent impermeability, chemical resistance, and ease of application, it is widely used in various applications.