Abstract:
Municipal solid waste produces leachate that contains huge amount of organic carbon,
metals, and nutrients. These contaminants deteriorate receiving environment. The harmful
affect of waste can only be reduced by keeping the leachate emissions in control. We checked
the feasibility of a bioretention media (compost) that could be used to underline the waste
to reduce the contaminant leaching from waste. Two experiments were conducted to analyze
compost as an adsorbent that can be used as a soil amendment to reduce the contaminant
discharge from the waste. In the first experiment, leachate from three organic streams was
characterized, followed by two leaching experiments with an objective of evaluating compost,
and amended compost as a retention media.
Leachate generated by the organic streams of municipal solid waste contained many times
higher contaminant levels than the environmental quality standards. The results from compost leaching experiments showed that compost may not be used directly as an adsorption
media because compost itself produced substantial amount of contaminants. The contaminant concentrations remained high through out the experimental period, which is equal to
a flux of 144 m. The biochar amendment did not improve the contaminant mobility from
the compost, instead the biochar amendment increased the particulate and dissolved organic
carbon concentrations. Sand + compost remained the most efficient mixture among all the
amendments for the retention of contaminants.
