Groundwater Quality Evaluation for Potable Use and Associated Human Health Risk in Gaobeidian City, North China Plain

Table 1

Descriptive statistics of concentrations of groundwater parameters.

Item	Min	Max	Average	Sd	Nation standards
K^+	0.300	1.100	0.656	0.262	—
Na^+	8.800	181.300	48.694	36.180	200.000
Ca^2+	22.044	94.990	54.776	18.741	—
Mg^2+	8.266	67.101	32.551	16.086	—
HCO3^−	214.056	712.311	352.352	108.600	—
CO3^2−	0.000	14.273	1.145	3.452	—
Cl^−	2.852	93.458	28.456	26.849	250.0
SO4^2−	6.200	132.400	43.006	36.574	250.0
F^−	0.000	2.615	0.595	0.566	1.50
NO3^−	0.480	44.100	8.369	11.051	88.600
NO2^−	0.000	0.088	0.008	0.019	3.000
Fe	0.000	0.161	0.022	0.042	0.300
As	0.000	0.002	0.000	0.001	0.010
Mn	0.000	0.455	0.093	0.133	0.100
Sr	0.000	1.179	0.572	0.293	—
Cr^6+	0.000	0.026	0.003	0.007	0.050
TH	89.071	429.480	270.819	92.453	450.0
TDS	277.759	778.615	467.627	157.071	1000.000
pH	7.640	8.430	8.012	0.177	6.5–8.5
I^−	0.000	0.078	0.032	0.027	0.080
NO3–N	0.000	9.960	1.568	2.624	20.000
NO2–N	0.000	0.270	0.017	0.054	1.000