Development of a methodology to assess the footprint of wastes

The ecological footprint (EF) is a widely used indicator to assess the sustainability of people, regions or business activities. Although this metric has grown in interest and popularity over the years, it has also been the subject of criticism and controversy. The advantages of an aggregated indicator are often overshadowed by the shortcomings of its corresponding methodology. One weakness of the EF is that it does not account for toxic or hazardous pollutants and wastes, which cannot be part of a closed biological cycle. The methodology developed in the present work estimates the EF of toxic and hazardous wastes considering a closed cycle modeled through a plasma process; a phenomenon that naturally occurs in stars and volcanoes. Wastes from industry can be treated in a thermal plasma gasification process, and, by developing a methodology to describe this process, the EF of hazardous wastes was calculated. A value of 56.5 gha was obtained, a figure on the same order of magnitude as that obtained in a previous study where a conventional ecological footprint methodology was applied to the same production process. (C) 2010 Elsevier B.V. All rights reserved.