Phytomeliorative efficiency of vegetation species composition on devastated landscapes, including landfills, is a key factor in improving the ecological state at both local and regional levels. This article presents results of assessing heavy metal content and phytomelioration potential of vegetation cover on devastated areas, particularly at the Bronytsia landfill (Lviv region, Ukraine). Depending on the edaphic and climatic conditions, the surface of the devastated territories may have significant phytomeliorative potential, which is an important component of the reclamation process. Urban green spaces play a multifunctional role in improving the environment by providing oxygen production, microclimate regulation, filtration, noise absorption, and decorative and aesthetic functions. The key indicator for assessing the level of phytomelioration in devastated areas is the phytomelioration efficiency coefficient (KFM). During the research at the landfill, various categories of plant communities were identified, such as frutocenoses, sylvacenoses, ruderalenoses, pratocenoses, and agrocenoses. The KFM estimation for each landfill site showed the following results: Site 1 (western side): KFM = 4.5; Site 2 (northern side): KFM = 4.0; Site 3 (eastern side): KFM = 5.0; Site 4 (southern side): KFM = 5.5; Site No. 5 (central part): KFM = 2.1; Site 6 (control): KFM = 6.55. The results obtained indicate the suitability of the study area for reclamation activities for minimizing the negative impact on the environment.