rates and DRASTIC weights. The input layers were separately ratedand weighted by AHP rates and DRASTIC weights, respectively. (Figs.7B and 8B) show the vulnerability map and percentage of the area,respectively. (Fig. 7B) reveals the dominance of “high” vulnerability classes in the southern part of the study area. Fig. 8B indicates that more than half of the total area is under high contamination risk. InTable 6, the correlation value was computed at 0.45, which is clearlya low correlation compared with the other modifications. There-fore, AHP–DRASTIC is unsuitable for investigating the vulnerablezones in the Kerman plain. Fig. 7C shows the vulnerability map for the modifiedDRASTIC–AHP. In the modified DRASTIC–AHP method, the ratesand weights of DRASTIC were changed with the Wilcoxon andAHP, respectively. Fig. 8C illustrates that one-third (33.5%) of the total area is highly vulnerable. This portion is mostly situated inthe southeast and northeast parts of the area. Furthermore, the western part of the area is not under high risk of contamination(Fig. 7C). A correlation value of 0.65 was obtained for the modifiedDRASTIC–AHP method (Table 6).Figs. 7D and 8D present the results of DRASTIC–AHP. InDRASTIC–AHP, the DRASTIC rates and AHP weights were appliedin each input layer. Table 6 shows that the Pearson’s correlationvalue was calculated at 0.81, indicating strong correlation. Thus,DRASTIC–AHP might be an appropriate method for the Kermanplain. As illustrated in Fig. 7D, the south and a small portion of the north are highly vulnerable, whereas the western part only has lowvulnerability. Fig. 8D shows that 31% of the total number of pixels inthis study is situated in “very high” and “high” vulnerability classes.For the AHP–AHP method, the rates and weights of DRASTIC were optimized with the AHP method. Figs. 7E and 8E present thevulnerability map and percentage of the area, respectively. Table 6displays the correlation value calculated at 0.83. Fig. 8E indicatesthat 37.51% of the area has low and very low vulnerability, 21.63%has moderate vulnerability, and 40.85% has high and very high vulnerability. A highly vulnerable region in the study area is located around the boundary of the map, which is mainly composed of highly permeable sand and gravel.