The reliable assessment of mechanical parameters (strength and deformation) of municipal solid waste is essential for slope stability analysis and the foundation's design on restored landfills. In remediated areas, the development of green energy infrastructure, such as photovoltaic panels and wind turbines, has become a common alternative. For the infrastructure development in restored areas, comprehensive site investigation is required. Assessing waste geotechnical parameters is extremely challenging due to the nature of the analyzed material. The composition, heterogeneity, and the degree of decomposition are only a few factors determining waste mechanical performance. The paper presents the evaluation of geotechnical strength parameters performed for the purpose of constructing the foundation of green energy facilities on a restored landfill site. The strength parameters of the waste were determined using CPT static investigation tests including geological boreholes drilled in the analyzed profiles. During the tests, cone resistance (qc) and sleeve friction (fs) were recorded. The values were used to determine the geotechnical parameters of waste. The anthropogenic material properties were classified as those represented by non-cohesive or cohesive soils, depending on the results obtained from CPT (mainly based on the friction coefficient Rf). Evaluated parameters were used to propose the safe development of green energy facilities at the restored landfill site.