S. Bozkurt et al., The long-term evolution of and transport processes in a self-sustained final cover on waste deposits, SCI TOTAL E, 271(1-3), 2001, pp. 145-168
A new principle for confinement of waste based on a self-sustained seal is
presented. The top cover is considered to consist of two main layers; an or
ganic carbon rich surface layer that is able to support vegetation and an i
norganic layer beneath it. The function of the cover is to mitigate oxidati
on and acidification of landfilled waste and hence the release of toxic met
als. It is suggested that forest soil formation and soil development could
prove to be valuable information sources for the study of the long-term beh
aviour of a final cover on waste deposits. Since the cover is expected to d
evelop in northern temperate climate the focus is on Spodosol soil. A numbe
r of simulations of the long-term behaviour of the final self-sustained lan
dfill cover are made, including the rates of influx of oxygen into the cove
r. A cover having a large portion of organic matter compared with a cover w
ith no organics can considerably decrease the oxygen concentration and thus
the influx of oxygen into a landfill. The calculated oxygen intrusion rate
for the former case is of the order of 0.05 kg m(-2) year(-1). Degradation
of the organics produces acids. Our simulations indicate that the pH-buffe
ring capacity of the mineral layer, represented by calcite and primary rock
minerals, will last for many thousands of years. (C) 2001 Elsevier Science
B.V. Ah rights reserved.