Assessment of groundwater quality near municipal solid waste landfill by an Aggregate Index Method

Abstract

Leachate generated from municipal solid waste landfill site affects the groundwater quality in the adjacent areas through percolation in the subsoil. In this study, Aggregate Index method is applied to determine the quality of groundwater around a municipal solid waste dumping site. As the aggregate index is an increasing function of the distance from the landfill site, the groundwater quality improves as one move away from the landfill site. Aggregate index decreases with increase in time. Thus, water quality goes down with time. It may be due to the reason that with the passage of time the solid waste material gets degraded and the waste constituents percolate down along with rainwater thereby polluting groundwater. Hence, some remedial measures are required to prevent further contamination of groundwater in the vicinity. Notations The following symbols are used in this paper: E = average error; I = aggregate index; m = exponent; N = number of subindices; n = parameter; p = parameter; q = quality variable; q c = characteristic value of q; * q = optimal value of q; r = subindex for q = 0; s = subindex; x = distance from landfill site; and * x = parameter. Subscripts a = aggregate index. 1493 c = computed; i = index; o = observed; and s = subindex.