Modeling of Groundwater Vulnerabilities Uncertainty Using GIS & Rough Set

Groundwater is an important source of fresh water supply in Iran. In the event of contamination, the restoration process for these resources is not always possible. One proper way to prevent contamination of aquifers is identifying vulnerable areas. The uncertain boundaries is affecting factor in aquifer modeling as a spatial phenomenon. Many theories have been proposed for uncertainty. In this study, Rough Set Theory and Geographic Information System (GIS) have been used in modeling of groundwater vulnerabilities uncertainty in DRASTIC model. Urmia plain which is the central plain near the Urmia Lake has been selected as the study area. Modeling with the use of Rough Set is performing in two high and low approximations. Accordingly the upper percent in the DRASTIC indicator for the high approximation was associated to the low to medium contamination potential and for the low approximation was associated to the very low contamination potential.