The dendrogram divided the 122 sampling sites into three clusters that were statistically significant by drawing a phenon line at linkage distance 15 as shown in Figure 2. According to this line, clusters 2 and 3 are linked to each other, showing parallel qualities of these two groups. Yet, cluster 1 is rather different than the other two, indicating different characteristics rather than clusters 2 and 3. The first cluster of the three clusters has 29 sample sites, the second cluster has 11, and the third cluster has 82 sites. Mean and Standard Deviations and percentage exceedance of maximum permissible limits of measured parameters of three clusters were calculated and they were discovered to vary greatly as tabulated in Table 6. The average concentrations of all the measured parameters were notably above in clusters 2 and 3 than in cluster 1. Figure 3 shows the Box and Whisker plots that were developed to distinguish between the variations of three clusters.
Table 6
Cluster-wise statistics of measured parameters
| Variables | C1 (29 sites) | C 2 (11 sites) | C 3 (82 sites) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Average | Std. Dev | Exceedance (%) | Average | Std. Dev | Exceedance (%) | Average | Std. Dev | Exceedance (%) | |
| Turbidity | 2.77 | 6.88 | 14 | 18.72 | 10.01 | 91 | 1.10 | 1.51 | 15 |
| Color | 5.90 | 13.87 | 7 | 141.73 | 91.51 | 91 | 5.50 | 10.42 | 7 |
| pH | 7.09 | 0.56 | 0 | 7.59 | 0.25 | 0 | 7.35 | 0.30 | 0 |
| Cl− | 57.93 | 28.42 | 0 | 117.18 | 42.84 | 0 | 135.21 | 134.04 | 11 |
| Total hardness | 97.35 | 60.27 | 3 | 378.00 | 115.30 | 91 | 374.88 | 163.61 | 82 |
| Total alkalinity | 71.66 | 31.29 | 0 | 353.64 | 107.50 | 100 | 318.54 | 117.49 | 83 |
| TDS | 209.00 | 116.79 | 3 | 641.91 | 141.55 | 82 | 716.03 | 416.64 | 77 |
| NO3− | 2.45 | 2.25 | 0 | 7.02 | 4.84 | 0 | 6.94 | 8.95 | 0 |
| NO2− | 0.004 | 0.01 | 0 | 0.02 | 0.01 | 0 | 0.02 | 0.03 | 0 |
| F− | 0.29 | 0.36 | 7 | 1.14 | 0.46 | 55 | 1.06 | 0.61 | 50 |
| Variables | C1 (29 sites) | C 2 (11 sites) | C 3 (82 sites) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Average | Std. Dev | Exceedance (%) | Average | Std. Dev | Exceedance (%) | Average | Std. Dev | Exceedance (%) | |
| Turbidity | 2.77 | 6.88 | 14 | 18.72 | 10.01 | 91 | 1.10 | 1.51 | 15 |
| Color | 5.90 | 13.87 | 7 | 141.73 | 91.51 | 91 | 5.50 | 10.42 | 7 |
| pH | 7.09 | 0.56 | 0 | 7.59 | 0.25 | 0 | 7.35 | 0.30 | 0 |
| Cl− | 57.93 | 28.42 | 0 | 117.18 | 42.84 | 0 | 135.21 | 134.04 | 11 |
| Total hardness | 97.35 | 60.27 | 3 | 378.00 | 115.30 | 91 | 374.88 | 163.61 | 82 |
| Total alkalinity | 71.66 | 31.29 | 0 | 353.64 | 107.50 | 100 | 318.54 | 117.49 | 83 |
| TDS | 209.00 | 116.79 | 3 | 641.91 | 141.55 | 82 | 716.03 | 416.64 | 77 |
| NO3− | 2.45 | 2.25 | 0 | 7.02 | 4.84 | 0 | 6.94 | 8.95 | 0 |
| NO2− | 0.004 | 0.01 | 0 | 0.02 | 0.01 | 0 | 0.02 | 0.03 | 0 |
| F− | 0.29 | 0.36 | 7 | 1.14 | 0.46 | 55 | 1.06 | 0.61 | 50 |
Figure 2
Dendrogram resulting from HCA.
Figure 3
Box–whisker plots of groundwater quality parameters.