Phytocapping is a sustainable landfill cover technology that utilises a vegetated soil cover to create a hydraulic barrier for compacted waste. The vegetation in phytocaps offers various environmental, ecological, and social benefits, including providing habitat for local flora and fauna and contributing to natural green spaces that mitigate air pollution and the urban heat island effect. Additionally, phytocap vegetation employs soil bioengineering to reinforce the soil, enhancing slope stability. Little research has focused on critical phytocapping design parameters, namely soil compaction and vegetation design, which significantly affect hydrological performance, as well as vegetation growth and survival. This thesis aims to inform landfill designers about optimal phytocap design by configuring soil compaction and vegetation design, using coal overburden material. The research comprises five stages that address the objectives. [...]