The concept of utilizing a rubber compound sheet (RCS) made from natural materials as a substitute for polymer plastics was investigated. In this study, the functions of RCS as a geomembrane were investigated. Testing on thickness, mass per unit area, tensile strength, and interface shear strength behavior under various environmental conditions or various curing conditions, including air, tap water, and wastewater (acid water (pH 6) and base water (pH 9)) for 90- and 180-curing days, were conducted. It was found that the properties of the RCS geomembrane, such as thickness, mass per unit area, tensile strength, and interface shear strength, were not affected by various curing conditions. The results confirmed that the RCS geomembrane can function as a geomembrane.
