Landfill mining (LFM) is emerging as a viable strategy to address the dual challenges of municipal solid waste accumulation and land scarcity, particularly in developing countries like India. This study investigates the environmental risks and reuse potential of gravel and soil-like material (GSLM), the main fraction recovered during LFM, from three legacy dumpsites at Delhi, India. Despite its visual similarity to natural soil, GSLM contains elevated concentrations of organic matter, heavy metals, and soluble salts, and generates dark-colored leachate, raising serious concerns for direct reuse. Laboratory analysis revealed significantly higher contaminant levels compared to background soils, often exceeding regulatory thresholds for unrestricted reuse. These findings highlight potential risks such as groundwater contamination and bioaccumulation, if GSLM is used in earthfills and SLM is used as a soil conditioner without protective measures and/or treatment. The study recommends design measures including surface capping, sealing layer etc., for fills, embankments, and reclaimed deep pits. Additionally, various treatment options have been screened for feasibility in resource-constrained contexts. The study underscores the critical need for thorough assessment and safe reuse protocols to ensure environmentally responsible valorization of GSLM in LFM initiatives.