Characterizing biogeochemical processes during landfill waste stabilization

In the Netherlands 2.5 million tons of waste is landfilled yearly. Current practice shields the environment from emitted landfill contaminants, yet the applied techniques require indefinite renewal of protective barriers, which is costly and unsustainable. Novel techniques strive to alter waste properties such that the contaminant emission of landfill waste is reduced to concentration levels that meet predetermined environmental protection criteria. These novel techniques, i.e. aeration of the landfill waste and recirculation of leachate, both aim to increase natural decomposition of the organic matter fraction of the waste. We know from soil organic matter that increased decomposition alters organic matter characteristics, decreases the dissolved/solid organic matter partitioning and increases the capacity of the remaining solid organic matter to bind contaminants. We expect similar behavior in landfill solid waste. Yet, research regarding the effect of aeration and leachate recirculation on the characteristics of solid organic matter in landfill waste has until now received little attention. We will investigate these effects, particularly with regard to the stability and contaminant binding properties of organic matter, by simulating aeration and leachate recirculation in specially designed landfill simulation reactors.