AHP-Based Impact Assessment Methodology for Selecting Land Application Strategies for Biochar Amended Sewage-Based Compost

The safe and responsible handling of municipal solid wastes has become extremely crucial due to its multitude impacts on the environment, economy and health sectors. The prospects of composting have been attractive for communities and industries to solve their daily disposal of organic-rich solid wastes. However, on a technical ground, the actual impact of composting has to be evaluated before being suggested as a perfect sustainable solution. Considering the recent developments in co-composting, selection of proper feedstock and the methods of compost preparation and application are to be evaluated by using screening-type models to reduce the environmental impacts. In this aspect, the present study proposes an analytical methodology for the environmental impact assessment of composting units operating at various sites, scales, feeds, duration and applications. In order to perform fast and fair decision-making, we followed a rapid assessment methodology by grouping together important parameters to identify the most critical activities and their corresponding impacts. Further, the consistency of the decision-making process was evaluated by employing an analytical hierarchy process (AHP) methodology using two-dimensional pair-wise correlation matrices for three major activities, such as biochar preparation, co-composting and land application of compost. The weights corresponding to the impact categories were evaluated using matrix operations and the impacts were quantified in terms of positive or negative scores, demonstrating the net impact of the project activities. The results of the study reveal the need for a comprehensive and adaptive decision support system and provide suggestions for a critical assessment methodology to promote sustainable waste management initiatives for residential communities.