Hydrochemical Analysis of Six Sacred Lakes …
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Table 1
Indian (BIS, 1991) and International (WHO, 2014) Standards for Drinking Water and concentration of various chemical parameters in the six lakes of
Sikkim (unit: mg/l except for pH, hardness and TDS)
Parameters BIS
WHO
Gurudrongmar
(L1)
Lamapokhari
(L2)
Khecheopalri
(L3)
Karthok
(L4)
Menmecho
(L5)
Kupup
(L6)
Acceptable Permissible Acceptable Permissible
pH
6.5–8.5
No
relaxation
7.0–8.5
6.5–9.2
7.1
6.4
6.9
6.7
7.0
6.8
DO
–
–
–
–
9.3
4.3
4.1
6.8
8.3
13
DO
5
–
–
–
–
8.9
3.5
3.1
5.4
6.1
10
Hardness
300
600
100
500
20
16
36
20
16
24
TDS
500
1500
500
1500
20
14
610
110
13
11
Na +
–
–
–
–
0.2
0.8
2.1
1.5
1.5
0.7
K +
–
–
–
–
6.6
7.6
7.3
7.9
6.3
7.3
Ca 2+
75
200
75
200
24
16
24
17
8
16
Mg 2+
30
100
<30
150
4.7
5.4
4.8
6
4.9
4.5
Cl −
250
1000
200
600
7.9
11.9
25
5.0
9.9
8.0
HCO
3
−
24.4
19.5
43.9
24.4
19.5
29.3
SO
2−
4
200
400
200
400
0.37
0.63
0.43
0.66
0.56
0.41
PO
3−
4
–
–
–
–
0.01
0.03
0.03
0.02
0.02
0.01
Bold indicates Anomalous high value