In this study, the Grade III standard in the National Quality Standard for Groundwater (GB/T 14848-93) is taken as the assessment criterion. Equation (5) is applied to compute the weights of each selected pollution parameter and the result is summarized in Table 1.

Table 1

Statistics summary of values of the weights of eight groundwater parameters

Groundwater parameters .	Grade III .	Weights (Wi) .
TH (mg/L)	≤450	4.32 × 10−5
COD (mg/L)	≤3.0	6.49 × 10−3
TDS (mg/L)	≤1,000	1.95 × 10−5
Cl− (mg/L)	≤250	7.78 × 10−5
(mg/L)	≤250	7.78 × 10−5
(mg/L)	≤20	9.73 × 10−4
(mg/L)	≤0.02	0.973
F− (mg/L)	≤1.0	0.0195

Groundwater parameters .	Grade III .	Weights (Wi) .
TH (mg/L)	≤450	4.32 × 10−5
COD (mg/L)	≤3.0	6.49 × 10−3
TDS (mg/L)	≤1,000	1.95 × 10−5
Cl− (mg/L)	≤250	7.78 × 10−5
(mg/L)	≤250	7.78 × 10−5
(mg/L)	≤20	9.73 × 10−4
(mg/L)	≤0.02	0.973
F− (mg/L)	≤1.0	0.0195

TH, Total hardness; COD, Chemical oxygen demand; TDS, Total dissolved solids.

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