Assessment Methodology and Application for Stabilization Process of Aged Municipal Solid Waste Landfills
Scientific assessment and prediction of the stabilization process in aged municipal solid waste (MSW) landfills are critical for reliable risk evaluation and remediation decision-making. Existing methods often fail under data-scarce conditions and lack temporal predictive capability. This study establishes a 'spatial characterization–temporal prediction' framework to address these gaps. The methodology integrates grid-based sampling, laboratory analysis of biological stability indicators (AT4), and LandGEM model simulations to assess current stabilization states and predict completion timelines. Applied to a landfill in southwest China, results reveal significant spatial heterogeneity in waste stabilization, strongly correlated with waste age and influenced by leachate recirculation of membrane concentrate. None of the landfill zones had reached full stabilization; predicted times to completion were: Zone D (17 years), Zone C (13 years), Zone B (8 years), and Zone A (1 year). Based on these findings, a systematic management strategy is proposed, including zoned gradient management, targeted control of lag zones, and dynamic planning. This study provides a theoretical basis for site-specific management and serves as a reference for similar landfills.