© 2019, Centro de Ciencias de la Atmosfera, UNAM. All rights reserved. Currently, the State of Mexico (SM), the most densely populated Mexican State generates more than 19 000 t/d of municipal solid waste (MSW), which is disposed in waste disposal sites (WDS). Therefore, landfill siting should consider territorial issues and legal framework to minimize negative impacts. However, the inadequate record and management at WDS makes it difficult to get precise data related to volumes, sources and composition of MSW disposed, as well as to estimate leachate and biogas emissions. The aim of this work was to determine the status of WDS in the SM, by applying a methodological approach based on the analysis of WDS location, waste handling, disposal practices, general operations, as well as the emission of biogas and leachate. Cartography of the area and geographical information systems (GIS) technology were used to generate spatial data for sites assessment, taking into account the factors and risk parameters for the operation of the WDS. Applying the assessment methodology to 83 WDS of the SM, it was determined the current situation of sites location regarding the distances from landfill location to restricted areas and their compliance with federal and state regulations established in Mexico. The findings of this study show that although the few sites properly managed as landfills receive the higher amount of waste, the vast majority of the studied sites in the SM operate improperly, generating biogas and leachate, which impact negatively on water, groundwater, air, soil and probably human health.