Geomembrane is a synthetic membrane or barrier used in geotechnical engineering and environmental applications. It is a flexible sheet made of various materials, such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyvinyl chloride (PVC), or ethylene propylene diene monomer (EPDM). Geomembranes are primarily used for containment, isolation, and protection purposes.