A membrane-assisted solvent extraction (MASX) system coupled to a membrane-assisted distillation stripping (MADS) system for use in decontaminating ground-water is evaluated. Volatile organic compounds (VOCs) in the groundwater are extracted in the MASX unit using a sunflower oil solvent. In the MADS unit, VOCs are stripped from the sunflower oil, which is recycled to the MASX unit. Thermodynamic data for the sunflower oil-water-VOCs system were measured. The results were used along with published membrane mass-transfer data to design MASX and MADS modules.