Community Engagement and Environmental Life Cycle Assessment of Kaikōura’s Biosolid Reuse Options

Abstract: This paper reports a life cycle assessment undertaken to assess the environmental impact of a range of biosolid reuse options selected by the Kaikōura community. The reuse options were identified as: vermiculture and open-air composting; mixture with biochar; direct land application to disturbed sites for forestry using native tree species; and application to exotic forestry plantations or pastoral farmland. The aim of the study was to calculate the possible environmental impacts of the reuse options so the information can be used in a community dialogue process where the fate of the biosolids is decided upon. All reuse options showed improved environmental performance relative to landfilling. The direct application to land options showed the least environmental impact and the composting options had the most environmental impact. This is the first time this approach has been applied to biosolids management in New Zealand, and whilst there are limitations, the approach should be encouraged in other communities because it increases the engagement of the community with waste management decision-making and the environment.