Retrieving material for composting from open dumps across the developing world could reduce the environmental impact of the growing mountains of waste, according to researchers in India.

Environmentalresearchweb newswire reports that open dumps are prevalent in the developing world and have a poor environmental record, according to environmental engineer Kurian Joseph and colleagues at Anna University in Chennai, India. Joseph and his team have considered the possibility of landfill mining as a viable means of rehabilitating open dumps.

An earlier analysis of decomposed waste from the Deonar dumpsite in Mumbai, India, has revealed that almost a third of the mass is organic matter, while moisture accounts for 14% of the sieved material and inert matter the same again. Soft plastics, textiles, glass, ceramics, metals, rubber, leather and other substances account for the remainder of the sieved mass.

"Landfill mining can recover recyclable materials, landfill space and compost," explains Joseph. He suggests that the mining of compost from open stabilized dumpsites and the application of the bioreactor landfill concept across the developing world could make dumps much more sustainable and reduce their environmental impact. The current study, funded by the Swedish International Development Co-operation Agency, indicates that up to half of the material dumped at such sites could be recovered and reused as compost for non-edible plants or as daily cover material for landfills.

During the last two decades, experimental testing and pilot field studies have been conducted to develop and improve landfill techniques and designs with the aim of reducing their negative impact on the environment. The researchers suggest that by encouraging microbial degradation of solid waste in landfill bioreactors it should be possible to improve the overall efficiency of the landfill mining process. This, they explain, needs to be demonstrated at the pilot scale to complement the ongoing research in this area.