The temperature factor is of great importance in areas that directly affect the environment and engineering parameters of liners, such as solid waste storage areas. It is known that the temperature value increases as a result of the degradation of waste in these areas, and temperature changes affect the engineering properties of the soils. Properties vary depending on the soil type, and additives that can be used to improve the engineering properties of soils come to the fore. One of the most important criteria is that the additive to be used is sustainable and environmentally friendly. Zostera marina, with its terminological name, or dried seaweed an aquatic plant and is a sustainable, low-cost material used in thermal insulation. In this study, dried seaweed additive was added to zeolite-bentonite mixtures and compression parameters were determined under room temperature and 40°C. Hydraulic conductivity values of seaweed-added mixtures were determined with the help of volumetric compression coefficient (mv) and consolidation coefficient (cv) parameters and empirical relationships obtained as a result of consolidation tests. Its potential to be used as a buffer material in the presence of temperature in solid waste storage areas evaluated. The tests results showed that the seaweed additive decreased the hydraulic conductivity values of zeolite-bentonite mixtures at room temperature and under 40°C.