Table 5.4 (continued)
Indicators
Detection limit
Unit
G1
G2
B1
Trans-1,2-dichloroethylene
0.5
lg/L
<0.5
<0.5
–
Cis-1,2-dichloroethylene
0.5
lg/L
<0.5
<0.5
–
1,1,1-trichloroethane
0.5
lg/L
<0.5
<0.5
–
Carbon tetrachloride
0.5
lg/L
<0.5
<0.5
–
1,2-dichloroethane
0.5
lg/L
<0.5
<0.5
–
Trichloroethylene
0.5
lg/L
<0.5
<0.5
–
1,1,2-trichloroethane
0.5
lg/L
<0.5
<0.5
–
Tetrachloroethylene
0.5
lg/L
<0.5
<0.5
–
Chlorobenzene
0.5
lg/L
<0.5
<0.5
–
1,3-dichlorobenzene
0.5
lg/L
<0.5
<0.5
–
1,4-dichlorobenzene
0.5
lg/L
<0.5
<0.5
–
1,2-dichlorobenzene
0.5
lg/L
<0.5
<0.5
–
1,2,4-trichlorobenzene
0.5
lg/L
<0.5
<0.5
–
Chloroform
0.5
lg/L
<0.5
<0.5
–
Bromomethylene chloride
0.5
lg/L
<0.5
<0.5
–
Dibromochloromethane
0.5
lg/L
<0.5
<0.5
–
Tribromomethane
0.5
lg/L
<0.5
<0.5
–
BaP
0.05
lg/L
<0.05
<0.05
–
Table 5.5 Quality standards for groundwater (GB/T14848–2017)
Indicators
Groundwater quality standards
Grade I
Grade II
Grade III
Grade IV
Grade V
pH
6.5–8.5
5.5–6.5
8.5–9.0
<5.5,
>9.0
Ammonia nitrogen
0.02
0.10
0.50
1.50
>1.50
Nitrite nitrogen
0.01
0.10
1.00
4.80
>4.80
Total cyanide
0.001
0.01
0.05
0.1
>0.1
Fluoride
1.0
1.0
1.0
2.0
>2.0
Nitrate nitrogen
2.0
5.0
20
30
>30
Chloride
50
150
250
350
>350
Sulfate
50
150
250
350
>350
Total soluble solids
300
500
1000
2000
>2000
Total hardness
150
300
450
650
>650
Permanganate index
1.0
2.0
3.0
10
>10
Volatile phenol
0.001
0.001
0.002
0.01
>0.01
Hexavalent Chromium
0.005
0.01
0.05
0.10
>0.10
Arsenic
0.001
0.001
0.01
0.05
>0.05
Cadmium
0.0001
0.001
0.005
0.01
>0.01
(continued)
5.1 Central China
103