Agricultural contaminant potential was modelled using an
integrated GIS-based MCE model. The MCE consisted of two parts, a
surface runoff component, and a groundwater component. Together, these
two components cover most of the possible contaminant pathways which
affect nearby fresh water resources from agricultural sources. Each
component is composed of a representative model, the USLETrans model
for contaminant transport to surface water, and the DRASTIC model for
contaminant transport to groundwater. The USLE is commonly used for
estimating long term relative soil erosion intensities (Stone &
Hilborn 2000); however, with the addition of a sediment transport
factor it is able to estimate the intensity of sediment and
accompanying agrochemicals entering
nearby surface waters. The DRASTIC model is frequently used to
determine the vulnerability of groundwater to surface contaminants
(Aller, et al. 1987). Both of the models are simple and accurate
(Al-Zabet 2002, Mihara, et al. 2005).
The following sections outline the research approach for each of the
five objectives:
Objective 1:
Identify the factors relating to soil erosion
Objective 2:
Identify the factors relating to groundwater contamination
Objective 3:
Develop an integrated GIS-based MCE model, unifying the USLE and
DRASTIC models to determine the potential of an area to contaminate
surface and groundwater
Objective 4:
Apply the GIS-based MCE model to examine the overall contamination
potential in the Fairchild Creek Watershed
Objective 5:
Assess the strengths and weaknesses of the integrated MCE model
