The city of Volta Redonda, located in the state of Rio de Janeiro, has a controlled landfill of municipal solid waste (MSW) which was partially recovered in 2008. This disposal site has no data on the amount of waste volume landfilled. An Unmanned Aerial Vehicle (UAV) was used to capture images of the study area and through Geographic Information Systems (GIS) the biogas generation was determined. By overlaying the georeferenced images the contour lines were determined which enabled the creation of the 3D Digital Terrain Model (DTM) of the area with a resolution of 0.296349 m / pix. The DTM provided the determination of the volume of waste landfilled (535.755,79 m³) and the real surface area (36.770,96 m²) of the controlled landfill. These parameters allowed obtainment the maximum flow rate of methane generation of 16.539,82 m³ for 2007. The Brazilian model used to determination biogas generation in waste sector achieve a maximum flow rate of methane generation of 126.599,4 m³ for the year 2007. A significant difference between biogas generation in the two models was observed mainly due to the amount of waste determined in both models.

A publicação do novo marco legal do saneamento básico no Brasil – LEI Nº 14.026, de 15 de julho de 2020 definiu novos prazos iminentes para encerramento dos 3326 “lixões” e aterros controlados no território nacional. A importância do fim das atividades ou s adequação das áreas de disposição irregular de RSU é primordial para a eliminação/redução da contaminação dos compartimentos ambientais. Com as dificuldades financeiras e índices de avaliação de qualidade de áreas de disposição subjetivos – IQR (CETESB) e IQDR (INEA) pouco foi feito pelos gestores municipais nessas áreas. A fim de superar a subjetividade na utilização desses índices e direcionar ações efetivas, este trabalho propõe um novo Índice de Qualidade de Áreas de Disposição Irregular de RSU (IQUADI), baseada na Análise Hierárquica de Processo (AHP), definindo-se intervalos específicos para os critérios selecionados a partir de levantamento bibliográfico e documental. Os resultados finais mostram aos responsáveis pelos passivos ambientais se as atividades na área serão encerradas ou continuarão e quais medidas a serem adotadas. Verificaram-se divergências legais nos limites usualmente utilizados e novos limites foram propostos para os critérios componentes do IQUADI. A aplicação comparativa (estudo de caso) do IQUADI e do IQR no aterro controlado de Volta Redonda permitiu concluir que o IQR apresenta 58% de subjetividade para a seleção dos pesos de cada critério, ao contrário do IQUADI que apresentou valores específicos para cada intervalo selecionado integrante dos critérios. Subjectivity reduction in the MSW disposal areas classification through a new index applying Hierarchical Process Analysis: Quality Index of Irregular MSW Disposal Areas – IQUADIA B S T R A C TThe new legal framework publication for basic sanitation in Brazil in July 2020 defined new imminent deadlines for the closure of the 3326 “dumps” and controlled landfills in the national territory. The importance of the end of activities or the adequacy of MSW irregular disposal areas is essential for the elimination / reduction of contamination of environmental compartments. With the financial difficulties and the subjectivity of the quality assessment indexes of disposal areas - IQR (CETESB) and IQDR (INEA), little has been accomplished by municipal managers in these areas. In order to overcome the subjectivity in the use of these indices and direct effective actions, this work proposes a new Quality Index for MSW Irregular Disposal Areas (IQUADI), based on the Analytic Hierarchy Process (AHP), defining specific intervals for the selected criteria from a bibliographic and documentary survey. The final results show those responsible for environmental liabilities whether activities in the area will be closed or will continue and what measures must be performed. Legal differences have been identified in the limits usually used and new values were proposed for the criteria that compose IQUADI. The comparative application (case study) of IQUADI and IQR in the controlled landfill of Volta Redonda allowed us to conclude that the IQR presents 58% subjectivity for the selection of the weights of each criterion, in contrast to the IQUADI which presented specific values for each interval selected integral to the criterion.Keywords: municipal solid waste, closure, quality index, analytical hierarchy process.