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In India, majority of the generated municipal solid waste (MSW) was dumped in poorly managed landfills and dumpsites over the past decades and is an environmental and health hazard. Landfill mining is a promising solution to reclaim these sites along with the recovery of resources (materials and energy). During landfill mining operations, the combustible fraction is one of the major components recovered and needs proper management for maximizing resource recovery. For the identification of appropriate resource recovery options, knowledge of the physicochemical characteristics is required. The present study aims to assess the depth-wise change in the composition of legacy waste and the physicochemical characteristics of the combustible fraction. Furthermore, a material flow analysis considering the incineration of combustible fraction was performed to estimate the energy generation potential and the associated greenhouse gas (GHG) emissions. The results of the compositional analysis of dry legacy waste revealed that the fine fraction (<4 mm soil-like material) was dominating with a share of 36%. The depth-wise analysis showed a decrease in the calorific value with increasing landfill depth, while no specific trend was observed for the other parameters analyzed, including proximate and ultimate analysis, and chlorine content. The material flow analysis performed for 100 tonnes of wet legacy waste indicated that 52 tonnes of waste is combustible fraction. The GHG emissions through incineration of one tonne of dry combustible fraction would be 1389 kg CO 2 -eq, with 1125 kWh of electrical energy generation potential. [Display omitted] • Changes in physicochemical characteristics with landfill depth were assessed. • The legacy waste had a high share of combustible fraction accounting for 52%. • The combustible fraction was found to be suitable for WtE treatment and use as RDF. • One tonne of legacy waste showed a potential to generate 428 kWh of electricity. • Incinerating one ton of combustible waste can emit 1389 kg CO 2 -eq of GHG emissions. [ABSTRACT FROM AUTHOR]

Increasing water stress and high energy requirements in urban water systems (UWSs) makes it imperative to reduce water demand by adopting wastewater reuse. However, there is a gap in the existing literature about analysing the operation of hilly urban water systems (UWSs) and suggesting energy efficient and environmentally benign wastewater reuse strategies. The objective of this study is to investigate the water-energy-greenhouse gas (GHG) nexus for different wastewater reuse strategies in UWS located in the Indian Himalayan region. Potential scenarios for the direct potable and non-potable reuse in the region were analysed. The system boundary consisted of the construction and operation phase inputs. The functional unit of the study was 1 m3 of water supplied to the UWS. The data inventory was developed using process designs, site specific information, engineering calculations and commercial databases. The total embodied energy and total GHG emissions were estimated using the existing models based on mass balance approach. The hilly UWS uses 17.6 kWh/m3 of total embodied energy and emits 6.2 kgCO 2 eq/m3 GHG emissions in its present operation. Over 90% of energy and GHG emissions were associated with pumping, which is required to cover over 1000 m of elevation head. The combined reuse scenario comprising both non-potable and direct potable reuse had the lowest embodied energy use and GHG emissions with a magnitude of 12.9 kWh/m3 and 4.3 kgCO 2 eq/m3. By comparative assessment of potential reuse scenarios, the study provides rationale for adopting appropriate strategy based on water savings, energy use, and environmental interventions. [Display omitted] • Assessment of urban water system in hilly terrain integrated with wastewater reuse. • Analysis of non-potable reuse, direct potable reuse and hybrid reuse scenarios. • Water pumping was the energy and GHG emission hotspot. • All but direct potable reuse had less energy and GHG emissions compared to baseline. • Hybrid reuse from the STP close to township had the lowest energy and GHG emissions. [ABSTRACT FROM AUTHOR]