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12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B 17 16 11 19 2.31 45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3 B&C 1.74 2.23 1.36 3.11 0.15 Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500- N&C,NO3 E 7.22 5.14 4.13 9.63 1.14 Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.85 0.64 0.11 0.5 0.14 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 133 142 45 216 258 Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 28 17 5 25 32 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 28 32 30 40 60 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 32 24 20 34 55 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 1.5 1.21 2.89 3.88 0.47 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D 0.07 BDL(< 0.02) 0.2 0.09 0.02 0.10
22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 5.2 5.5 6.6 5.1 5.5 Not Specified
23 Chemical Oxygen
Demand mg/l IS:3025:Part-58:2006 (Reaff:2012) 36 54 17 33 26 Not Specified
24 Bio-Chemical Oxygen
Demand @ 27°C for 3 days mg/l IS:3025:Part-44:1993 (Reaff:2014) 6.7 8.2 2.1 4.4 4.1 Not Specified
25 Copper as Cu mg/l APHA 22nd Edition -3111 B 0.1 BDL(< 0.03) BDL(< 0.03) 0.12 BDL(< 0.03) 0.05
26 Mercury as Hg mg/l APHA 22nd Edition -3112 B BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(<
0.001) BDL(< 0.001) 0.001
27 Cadmium as Cd mg/l APHA 22nd Edition -3111 B BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(<
0.003) BDL(< 0.003) 0.003
28 Total Arsenic as As mg/l APHA 22nd Edition -3114 B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) 0.01
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29 Cyanide as CN mg/l APHA 22nd Edition -4500 CN BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) 0.05
30 Lead as Pb mg/l APHA 22nd Edition -3111 B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) 0.01
31 Zinc as Zn mg/l APHA 22nd Edition -3111 B 0.41 0.841 0.214 0.166 0.214 5
32 Hexavalent Chromium as
Cr6+ mg/l APHA 22nd Edition -3500 Cr B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) Not Specified
33 Total Chromium as Cr mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) 0.05
34 Nickel as Ni mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) 0.02
35 Sodium Absorption Ratio _ Calculation 4.07 4.62 1.56 6.06 5.78 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.6 1.1 0.3 1.6 1.2 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 70 80 76 100 150 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B 130 100 84 140 230 Not Specified
39 Molybdenum as Mo mg/l APHA 22nd Edition -3111 D BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) 0.07
40 Total Coliform MPN/
100ml IS :1622 (1981) 300 350 90 110 30 Absent
41 Faecal coliform MPN/
100ml IS:1622 (1981) 6 17 11 14 4 Absent
BDL- Below Detection Limit
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TABLE – 3.13(c): SURFACE WATER ANALYSIS RESULTS
S.No Parameters Unit Procedure SW11 SW12 SW13 SW14 SW15
Acceptable
Limit as per IS
10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) 25 22 12 3 6 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 26.8 26 5 25.5 25.7 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 7.42 7.3 7.15 7.24 7.31 6.5-8.5
4 Electrical Conductivity μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012) 1590 345 807 342 990 Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 10.8 8.2 7.7 1.6 2.2 1
6 Total Dissolved Solids mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 890 188 460 207 562 500
7 Total Hardness as CaCO3 mg/l IS : 3025 Part 21-2009 (Reaff: 2014) 220 100 200 132 120 200
8 Total Alkalinity as CaCO3 mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 240 144 140 140 240 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 317 28 149 26 116 250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500- SO42- E 96 2 31 10 65 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.64 0.13 0.33 0.34 0.81 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B 5 <1 12 6 1.7 45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3 B&C 1.44 0.57 1.63 5.6 1.36 Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500- N&C,NO3 E 2.63 1.75 5.74 2.36 2.05 Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.46 0.18 0.19 0.44 0.31 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 220 33 63 18 140 Not Specified
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17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 27 4.5 32 8 33 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 20 22 52 27 16 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 41 11 17 16 19 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 1.41 2.82 0.3 1.23 0.31 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D BDL(< 0.02) 0.19 BDL(< 0.02) BDL(<0.02) BDL(< 0.02) 0.10
22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 4.8 6.4 6.1 6.2 5.9 Not Specified
23 Chemical Oxygen
Demand mg/l IS:3025:Part-58:2006 (Reaff:2012) 60 24 30 22 16 Not Specified
24 Bio-Chemical Oxygen
Demand @ 27°C for 3 days mg/l IS:3025:Part-44:1993 (Reaff:2014) 10.4 3.6 4.1 2 2 Not Specified
25 Copper as Cu mg/l APHA 22nd Edition -3111 B 0.11 BDL(< 0.03) 0.11 BDL(< 0.03) BDL(< 0.03) 0.05
26 Mercury as Hg mg/l APHA 22nd Edition -3112 B BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) 0.001
27 Cadmium as Cd mg/l APHA 22nd Edition -3111 B BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) 0.003
28 Total Arsenic as As mg/l APHA 22nd Edition -3114 B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) 0.01
29 Cyanide as CN mg/l APHA 22nd Edition -4500 CN BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) 0.05
30 Lead as Pb mg/l APHA 22nd Edition -3111 B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) 0.01
31 Zinc as Zn mg/l APHA 22nd Edition -3111 B 0.214 0.26 0.171 0.01 0.123 5
32 Hexavalent Chromium as
Cr6+ mg/l APHA 22nd Edition -3500 Cr B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) Not Specified
33 Total Chromium as Cr mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) 0.05
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34 Nickel as Ni mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) 0.02
35 Sodium Absorption Ratio _ Calculation 6.47 1.43 1.94 0.68 5.60 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.9 0.2 0.5 0.2 0.6 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 50 56 130 68 40 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B 170 44 70 64 80 Not Specified
39 Molybdenum as Mo mg/l APHA 22nd Edition -3111 D BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) 0.07
40 Total Coliform MPN/
100ml IS :1622 (1981) 280 17 500 170 140 Absent
41 Faecal coliform MPN/
100ml IS:1622 (1981) 9 5 23 6 9 Absent
BDL- Below Detection Limit
TABLE – 3.13(d): SURFACE WATER ANALYSIS RESULTS
S.No Parameters Unit Procedure SW16 SW17 SW18 SW19 SW20
Acceptable
Limit as per IS
10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) 20 12 20 15 30 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 26.1 26 25.8 25.5 26.3 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 6.69 7.36 7.29 7.09 7.01 6.5-8.5
4 Electrical Conductivity μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012) 3170 912 1740 1370 2680 Not Specified
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5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 8.6 5.2 8.4 8.6 9.2 1
6 Total Dissolved Solids mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 1798 537 932 730 1486 500
7 Total Hardness as CaCO3 mg/l IS : 3025 Part 21-2009 (Reaff: 2014) 540 110 110 140 310 200
8 Total Alkalinity as CaCO3 mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 140 266 200 270 380 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 750 115 342 217 468 250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500- SO42- E 312 45 125 60 210 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.63 1.8 0.51 0.97 1.63 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B 27 3.8 5 7 4.5 45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3 B&C 7.8 1.81 1.23 2.69 5.63 Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500- N&C,NO3 E 13.8 2.71 3.11 4.12 7.75 Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.17 0.06 0.49 3.2 2 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 342 169 273 164 366 Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 108 4 28 68 52 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 88 12 20 36 56 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 77 19 14 12 41 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 2.16 3.58 1.96 3.63 4.1 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) 0.14 BDL(< 0.02) 0.10
22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 4.9 5 4.6 5.1 4.7 Not Specified
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23 Chemical Oxygen
Demand mg/l IS:3025:Part-58:2006 (Reaff:2012) 48 36 60 42 52 Not Specified
24 Bio-Chemical Oxygen
Demand @ 27°C for 3 days mg/l IS:3025:Part-44:1993 (Reaff:2014) 7.2 4.5 9.1 6.3 8.8 Not Specified
25 Copper as Cu mg/l APHA 22nd Edition -3111 B BDL(< 0.03) BDL(< 0.03) BDL(< 0.03) 0.14 BDL(< 0.03) 0.05
26 Mercury as Hg mg/l APHA 22nd Edition -3112 B BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(<
0.001) BDL(< 0.001) 0.001
27 Cadmium as Cd mg/l APHA 22nd Edition -3111 B BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(<
0.003) BDL(< 0.003) 0.003
28 Total Arsenic as As mg/l APHA 22nd Edition -3114 B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(<
0.01) BDL(< 0.01) 0.01
29 Cyanide as CN mg/l APHA 22nd Edition -4500 CN BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(<
0.05) BDL(< 0.05) 0.05
30 Lead as Pb mg/l APHA 22nd Edition -3111 B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(<
0.01) BDL(< 0.01) 0.01
31 Zinc as Zn mg/l APHA 22nd Edition -3111 B 0.133 0.01 0.74 0.01 0.01 5
32 Hexavalent Chromium as
Cr6+ mg/l APHA 22nd Edition -3500 Cr B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01)
BDL(<
0.01) BDL(< 0.01) Not Specified
33 Total Chromium as Cr mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(<
0.02) BDL(< 0.02) 0.05
34 Nickel as Ni mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(<
0.02) BDL(< 0.02) 0.02
35 Sodium Absorption Ratio _ Calculation 6.42 7.06 11.44 6.04 9.06 Not Specified
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36 Salinity %0 APHA 22nd Edition -2520 B 1.8 0.9 0.9 0.7 1.5 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 220 30 50 90 140 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B 92 80 60 50 170 Not Specified
39 Molybdenum as Mo mg/l APHA 22nd Edition -3111 D BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(<
0.05) BDL(< 0.05) 0.07
40 Total Coliform MPN/
100ml IS :1622 (1981) 900 350 280 170 110 Absent
41 Faecal coliform MPN/
100ml IS:1622 (1981) 50 26 14 14 9 Absent
BDL- Below Detection Limit
TABLE – 3.13(e): SURFACE WATER ANALYSIS RESULTS
S.No Parameters Unit Procedure SW21 SW22 SW23 SW24 SW25
Acceptable
Limit as per IS
10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) 6 5 15 5 3 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 26.6 26.1 25.7 26 24.9 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 7.39 7.21 7.06 7.27 7.2 6.5-8.5
4 Electrical Conductivity μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012) 941 590 996 1252 580 Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 3.3 3.1 8.3 4.5 1.8 1
6 Total Dissolved Solids mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 522 341 568 660 326 500
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7 Total Hardness as CaCO3 mg/l IS : 3025 Part 21-2009 (Reaff: 2014) 210 230 176 212 140 200
8 Total Alkalinity as CaCO3 mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 270 180 111 180 148 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 135 75 218 234 67 250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500- SO42- E 32 30 34 59 36 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.74 0.64 0.64 0.45 0.27 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B BDL(< 1) 1 28 6 3.5 45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3 B&C 0.14 0.05 0.82 0.87 0.26 Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500- N&C,NO3 E 2 1.11 15.1 3.74 1.96 Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.2 0.15 0.04 0.45 0.35 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 96 33 132 142 50 Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 11 16 11 40 33 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 44 40 42 48 29 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 40 31 17 22 16 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 0.41 0.56 2.01 0.71 0.69 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D BDL(< 0.02) BDL(< 0.02) BDL (< 0.02) 0.11 0.03 0.10
22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 6.5 6.4 6.3 6.1 6.4 Not Specified
23 Chemical Oxygen
Demand mg/l IS:3025:Part-58:2006 (Reaff:2012) 12 18 17 21 16 Not Specified
24 Bio-Chemical Oxygen
Demand @ 27°C for 3 days mg/l IS:3025:Part-44:1993 (Reaff:2014) 2 2.6 2.4 3 2.4 Not Specified
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25 Copper as Cu mg/l APHA 22nd Edition -3111 B BDL(<0.03) BDL(<0.03) BDL(<0.03) BDL(<0.03) BDL(<0.03) 0.05
26 Mercury as Hg mg/l APHA 22nd Edition -3112 B BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) 0.001
27 Cadmium as Cd mg/l APHA 22nd Edition -3111 B BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) 0.003
28 Total Arsenic as As mg/l APHA 22nd Edition -3114 B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) 0.01
29 Cyanide as CN mg/l APHA 22nd Edition -4500 CN BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) 0.05
30 Lead as Pb mg/l APHA 22nd Edition -3111 B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) 0.01
31 Zinc as Zn mg/l APHA 22nd Edition -3111 B 0.17 0.091 0.33 0.41 0.13 5
32 Hexavalent Chromium as
Cr6+ mg/l APHA 22nd Edition -3500 Cr B BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) BDL(< 0.01) Not Specified
33 Total Chromium as Cr mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) 0.05
34 Nickel as Ni mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) 0.02
35 Sodium Absorption Ratio _ Calculation 2.52 0.95 4.34 4.25 1.85 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.5 0.4 0.6 0.7 0.3 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 110 100 106 120 72 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B 100 130 70 92 68 Not Specified
39 Molybdenum as Mo mg/l APHA 22nd Edition -3111 D BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) BDL(< 0.05) 0.07
40 Total Coliform MPN/
100ml IS :1622 (1981) 60 170 140 110 23 Absent
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41 Faecal coliform MPN/
100ml IS:1622 (1981) 9 26 14 17 2 Absent
BDL- Below Detection Limit
TABLE – 3.13(f): SURFACE WATER ANALYSIS RESULTS
S.No Parameters Unit Procedure SW26 SW27 SW28 SW29 SW30
Acceptable
Limit as per IS
10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) 3 2 5 3 15 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 25.7 25.4 25.7 25.7 26.4 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 6.69 7.38 6.61 6.35 7.39 6.5-8.5
4 Electrical Conductivity μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012) 394 291 348 322 2450 Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 2 1.5 2.8 2.1 6.6 1
6 Total Dissolved Solids mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 211 161 184 174 1398 500
7 Total Hardness as CaCO3 mg/l IS : 3025 Part 21-2009 (Reaff: 2014) 124 110 112 124 320 200
8 Total Alkalinity as CaCO3 mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 121 100 136 128 370 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 44 27 26 21 486 250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500- SO42- E 16 11 9 11 195 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.36 0.63 0.4 0.56 0.61 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B BDL(< 1) BDL(< 1) BDL(< 1) BDL(< 1) 22 45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3 B&C 0.1 0.05 0.23 0.34 0.18 Not Specified
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14 Total Nitrogen as N mg/l APHA 22nd Edition -4500- N&C,NO3 E 1.11 1 1.1 1.3 12.7 Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.03 0.32 0.11 0.03 0.13 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 29 15 27 21 390 Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 9 3 3 4.4 10 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 27 24 24 24 116 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 13 13 12.5 15 7 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 0.26 0.25 0.66 0.37 1.51 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) BDL(< 0.02) 0.02 0.10
22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 6.7 6.5 6.8 6.7 5.2 Not Specified
23 Chemical Oxygen
Demand mg/l IS:3025:Part-58:2006 (Reaff:2012) 18 16 24 30 36 Not Specified
24 Bio-Chemical Oxygen
Demand @ 27°C for 3 days mg/l IS:3025:Part-44:1993 (Reaff:2014) 2.4 2.2 3.7 4.2 4.8 Not Specified
25 Copper as Cu mg/l APHA 22nd Edition -3111 B BDL(<0.03) BDL(<0.03) BDL(<0.03
) BDL(<0.03)
BDL(<0.03
) 0.05
26 Mercury as Hg mg/l APHA 22nd Edition -3112 B BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) 0.001
27 Cadmium as Cd mg/l APHA 22nd Edition -3111 B BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) 0.003
28 Total Arsenic as As mg/l APHA 22nd Edition -3114 B BDL(< 0.01) BDL(< 0.01) BDL(<
0.01) BDL(< 0.01)
BDL(<
0.01) 0.01
29 Cyanide as CN mg/l APHA 22nd Edition -4500 CN BDL(< 0.05) BDL(< 0.05) BDL(<
0.05) BDL(< 0.05)
BDL(<
0.05) 0.05
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30 Lead as Pb mg/l APHA 22nd Edition -3111 B BDL(< 0.01) BDL(< 0.01) BDL(<
0.01) BDL(< 0.01)
BDL(<
0.01) 0.01
31 Zinc as Zn mg/l APHA 22nd Edition -3111 B 0.21 0.14 0.08 0.10 0.42 5
32 Hexavalent Chromium as
Cr6+ mg/l APHA 22nd Edition -3500 Cr B BDL(< 0.01) BDL(< 0.01)
BDL(<
0.01) BDL(< 0.01)
BDL(<
0.01) Not Specified
33 Total Chromium as Cr mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(<
0.02) BDL(< 0.02)
BDL(<
0.02) 0.05
34 Nickel as Ni mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(<
0.02) BDL(< 0.02)
BDL(<
0.02) 0.02
35 Sodium Absorption Ratio _ Calculation 1.15 0.61 1.11 0.83 9.50 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.2 0.3 0.2 0.2 1.4 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 68 60 60 60 290 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B 56 50 52 64 30 Not Specified
39 Molybdenum as Mo mg/l APHA 22nd Edition -3111 D BDL(< 0.05) BDL(< 0.05) BDL(<
0.05) BDL(< 0.05)
BDL(<
0.05) 0.07
40 Total Coliform MPN/
100ml IS :1622 (1981) 23 50 110 240 900 Absent
41 Faecal coliform MPN/
100ml IS:1622 (1981) 4 11 14 33 90 Absent
BDL- Below Detection Limit
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TABLE – 3.13(g): SURFACE WATER ANALYSIS RESULTS
S.No Parameters Unit Procedure SW31 SW32 SW33 SW34 SW35
Acceptable
Limit as per IS
10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) 50 3 40 6 20 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 25.7 25.7 25.3 26.3 25.4 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 7.23 7.52 7.42 7.17 7.51 6.5-8.5
4 Electrical Conductivity μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012) 1090 378 390 440 1905 Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 12.2 1.9 10.8 2.7 6.2 1
6 Total Dissolved Solids mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 660 251 212 251 990 500
7 Total Hardness as CaCO3 mg/l IS : 3025 Part 21-2009 (Reaff: 2014) 270 128 104 144 340 200
8 Total Alkalinity as CaCO3 mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 290 176 70 140 320 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 213 32 74 50 288 250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500- SO42- E 84 16 14 7 149 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.6 0.59 0.18 0.44 0.58 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B 31 BDL(< 1) BDL(< 1) 12 7 45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3 B&C 0.26 0.13 1.11 0.15 1.36 Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500- N&C,NO3 E 22.8 1.42 2.8 8.24 3.33 Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.08 0.02 0.14 0.08 1.6 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 166 45 32 28 208 Not Specified
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17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 20 11 13 15 7.4 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 56 27 27 24 64 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 31 14 9 20 43 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 3.65 0.74 5.2 0.62 1.91 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D 0.07 BDL(< 0.02) 0.6 <0.02 0.02 0.10
22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 5.5 5.7 6.1 6.2 4.9 Not Specified
23 Chemical Oxygen
Demand mg/l IS:3025:Part-58:2006 (Reaff:2012) 36 32 16 20 58 Not Specified
24 Bio-Chemical Oxygen
Demand @ 27°C for 3 days mg/l IS:3025:Part-44:1993 (Reaff:2014) 5.3 5.2 2.4 2.5 8.8 Not Specified
25 Copper as Cu mg/l APHA 22nd Edition -3111 B BDL(<0.03) BDL(<0.03) BDL(<0.03
) BDL(<0.03) BDL(<0.03) 0.05
26 Mercury as Hg mg/l APHA 22nd Edition -3112 B BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) 0.001
27 Cadmium as Cd mg/l APHA 22nd Edition -3111 B BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) 0.003
28 Total Arsenic as As mg/l APHA 22nd Edition -3114 B BDL(< 0.01) BDL(< 0.01) BDL(<
0.01) BDL(< 0.01) BDL(< 0.01) 0.01
29 Cyanide as CN mg/l APHA 22nd Edition -4500 CN BDL(< 0.05) BDL(< 0.05) BDL(<
0.05) BDL(< 0.05) BDL(< 0.05) 0.05
30 Lead as Pb mg/l APHA 22nd Edition -3111 B BDL(< 0.01) BDL(< 0.01) BDL(<
0.01) BDL(< 0.01) BDL(< 0.01) 0.01
31 Zinc as Zn mg/l APHA 22nd Edition -3111 B 0.29 0.24 0.14 0.17 0.814 5
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32 Hexavalent Chromium as
Cr6+ mg/l APHA 22nd Edition -3500 Cr B BDL(< 0.01) BDL(< 0.01)
BDL(<
0.01) BDL(< 0.01) BDL(< 0.01) Not Specified
33 Total Chromium as Cr mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(<
0.02) BDL(< 0.02) BDL(< 0.02) 0.05
34 Nickel as Ni mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(<
0.02) BDL(< 0.02) BDL(< 0.02) 0.02
35 Sodium Absorption Ratio _ Calculation 4.41 1.74 1.61 1.02 4.92 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.7 0.3 0.2 0.3 1 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 140 68 68 60 160 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B 130 68 36 84 180 Not Specified
39 Molybdenum as Mo mg/l APHA 22nd Edition -3111 D BDL(< 0.05) BDL(< 0.05) BDL(<
0.05) BDL(< 0.05) BDL(< 0.05) 0.07
40 Total Coliform MPN/
100ml IS :1622 (1981) 500 240 70 110 900 Absent
41 Faecal coliform MPN/
100ml IS:1622 (1981) 60 23 14 17 70 Absent
BDL- Below Detection Limit
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TABLE – 3.13(h): SURFACE WATER ANALYSIS RESULTS
S.No Parameters Unit Procedure SW36 SW37 SW38 SW39 SW40
Acceptable
Limit as per IS
10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) 30 12 5 12 25 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 25.2 25.8 26.1 25.1 25.4 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 7.1 7.05 7.27 7.25 7.06 6.5-8.5
4 Electrical Conductivity μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012) 916 568 392 2220 789 Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 6.9 5.2 2.7 8.2 7.6 1
6 Total Dissolved Solids mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 512 318 220 1288 442 500
7 Total Hardness as CaCO3 mg/l IS : 3025 Part 21-2009 (Reaff: 2014) 204 122 118 450 160 200
8 Total Alkalinity as CaCO3 mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 185 171 132 391 177 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 166 61 34 407 101 250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500- SO42- E 24 21 20 120 48 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.5 0.46 0.43 0.54 0.58 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B 21 1 <1 14 13 45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3 B&C 0.71 0.36 0.1 0.22 0.26 Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500- N&C,NO3 E 12.2 1.21 0.72 8.21 6.97 Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.12 0.26 0.03 0.08 0.49 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 113 53 36 282 70 Not Specified
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17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 10.4 25 6 22 39 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 38 25 26 108 42 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 27 15 13 44 14 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 3.6 1.61 3.74 2.07 2.96 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D 0.1 0.07 0.04 0.05 0.09 0.10
22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 6.2 4.9 6.6 6.1 5.1 Not Specified
23 Chemical Oxygen Demand mg/l IS:3025:Part-58:2006 (Reaff:2012) 24 40 17 14 36 Not Specified
24 Bio-Chemical Oxygen
Demand @ 27°C for 3 days mg/l IS:3025:Part-44:1993 (Reaff:2014) 3.9 5.4 2.9 2.7 4.1 Not Specified
25 Copper as Cu mg/l APHA 22nd Edition -3111 B BDL(<0.03) BDL(<0.03) BDL(<0.03
) BDL(<0.03) BDL(<0.03) 0.05
26 Mercury as Hg mg/l APHA 22nd Edition -3112 B BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) BDL(< 0.001) 0.001
27 Cadmium as Cd mg/l APHA 22nd Edition -3111 B BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) BDL(< 0.003) 0.003
28 Total Arsenic as As mg/l APHA 22nd Edition -3114 B BDL(< 0.01) BDL(< 0.01) BDL(<
0.01) BDL(< 0.01) BDL(< 0.01) 0.01
29 Cyanide as CN mg/l APHA 22nd Edition -4500 CN BDL(< 0.05) BDL(< 0.05) BDL(<
0.05) BDL(< 0.05) BDL(< 0.05) 0.05
30 Lead as Pb mg/l APHA 22nd Edition -3111 B BDL(< 0.01) BDL(< 0.01) BDL(<
0.01) BDL(< 0.01) BDL(< 0.01) 0.01
31 Zinc as Zn mg/l APHA 22nd Edition -3111 B 0.14 0.63 0.14 0.25 0.17 5
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32 Hexavalent Chromium as
Cr6+ mg/l APHA 22nd Edition -3500 Cr B BDL(< 0.01) BDL(< 0.01)
BDL(<
0.01) BDL(< 0.01) BDL(< 0.01) Not Specified
33 Total Chromium as Cr mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(<
0.02) BDL(< 0.02) BDL(< 0.02) 0.05
34 Nickel as Ni mg/l APHA 22nd Edition -3111 B BDL(< 0.02) BDL(< 0.02) BDL(<
0.02) BDL(< 0.02) BDL(< 0.02) 0.02
35 Sodium Absorption Ratio _ Calculation 3.42 2.06 1.43 5.77 2.38 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.5 0.3 0.2 1.3 0.5 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 94 62 64 270 104 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B 110 60 54 180 56 Not Specified
39 Molybdenum as Mo mg/l APHA 22nd Edition -3111 D BDL(< 0.05) BDL(< 0.05) BDL(<
0.05) BDL(< 0.05) BDL(< 0.05) 0.07
40 Total Coliform MPN/
100ml IS :1622 (1981) 140 900 240 170 500 Absent
41 Faecal coliform MPN/
100ml IS:1622 (1981) 12 80 26 23 50 Absent
BDL- Below Detection Limit
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3.9.4 Observations
Ground Water
The pH value of the collected ground water in the study area found to be in the range from 7.47 to 8.41 and conductivity observed in the range 380 µS/cm to 3150
µS/cm, which qualifies it for Class E. TDS values were observed to be in range from 217 mg/L to 1827 mg/L. Total alkalinity is found to be the range from 124
mg/L to 390 mg/L and Total Hardness ranges from 140 to 796 mg/L. The chloride values of the samples were observed from 35 mg/L to 955 mg/L and Sulphate
values were observed from 3 mg/L to 128 mg/L. Iron content found in the range up to 3 mg/l. The Calcium and magnesium values were ranged from 16 mg/L to
163 mg/L and 15 mg/L to 93 mg/L respectively. Most of the metals are observed as below the detection limit. Dissolved Oxygen (DO) level were observed to be
between 3.4 and 4.8 ml/l which qualifies it for class A. Total Coliforms were observed to be <2 MPN/100 ml to 40 MPN/100 ml and Fecal Coliforms were observed
to be <2 MPN/100 ml at Locations, which qualifies it for Class A. Considering the above classification the source can be classified as Class A i.e. suitable for
drinking water source without conventional treatment but after disinfection.
Surface Water
The pH value of the collected surface water in the study area found to be in the range from 6.35 to 7.52 and conductivity observed in the range 270 µS/cm to
3170 µS/cm, which qualifies it for class E. TDS values were observed to be in range from 161 mg/L to 1798 mg/ L. Total alkalinity is found to be the range from
70 mg/L to 391 mg/L and Total Hardness ranges from 100 to 540 mg/L. The chloride values of the samples were observed from 21 mg/L to 750 mg/L and Sulphate
values were observed from 2 mg/L to 312 mg/L. The Calcium and magnesium values were ranged from 12 mg/L to 116 mg/L and 7 mg/L to 77 mg/L respectively.
Iron Content found in the range from 0.25 mg/l to 5.26 mg/l. Most of the metals are observed to be within the detection limit. COD values found in the range from
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14 mg/l to 60 mg/l. Total Coliforms were observed Between 17 MPN/100ml and 900 MPN/100ml and Fecal Coliforms were observed between 2 MPN/100ml and
90 MPN/100ml.
Surface water quality were also assessed against water quality criteria as per CPCB guidelines for aquatic resources, which shows that all the water samples
were unfit for drinking purposes
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Primary Water Quality Criteria for designated –Best –Use-Classes
Designated-Best-Use Category Criteria Description
Drinking Water Source without conventional treatment but after disinfection
A Total Coliforms Organism MPN/100ml shall be 50 or less pH between 6.5 and 8.5
Dissolved Oxygen 6mg/l or more
Biochemical Oxygen Demand 5 days 200C 2mg/l or less
Outdoor Bathing (Organized) B Total Coliforms Organism MPN/100ml shall be 500 or less pH between 6.5 and 8.5
Dissolved Oxygen 5mg/l or more
Biochemical Oxygen Demand 5 days 200C 3mg/l or less
Drinking Water source after conventional treatment and disinfection
C Total Coliforms Organism MPN/100ml shall be 5000 or less pH between 6 to 9
Dissolved Oxygen 4mg/l or more
Biochemical Oxygen Demand 5 days 200C 3mg/l or less
Propagation of wild life and Fisheries
D pH between 6.5 to 8.5
Dissolved Oxygen 4mg/l or more
Free Ammonia (as N) 1.2mg/l or less
Irrigation, Industrial Cooling, Controlled Waste Disposal
E pH between 6.0 and 8.5
Electrical Conductivity at 250C micro mhos/cm Max.2250
Sodium Absorption Ratio Max.26
Boron Max. 2mg/l
Biochemical Oxygen Demand 5 days 200C 2mg/l or less
Below E Not Meeting A,B,C,D&E Criteria
Source : CPCB
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3.10. Soil Quality Monitoring
To study the soil quality of the region, sampling locations were selected to assess the existing soil
conditions in and around the project area representing various land use conditions. The physical and
chemical concentrations were determined.
The present study of the soil quality establishes the baseline characteristics of soil and this will help in
future in identifying the incremental concentration changes if any, due to the operation in the proposed
project.
3.10.1 Sampling and Analysis Techniques
Soil samples were collected from three different depths viz., 30cm, 60cm, and 100cm below the surface.
The samples were analyzed for physical and chemical characteristics. The samples have been analyzed
as per the established scientific methods for physio-chemical parameters.
3.10.2 Details of Soil Sampling Locations
Soil samples were collected at twenty locations covering the study area of the proposed blocks. The
locations were tabulated as Table -3.14. The sampling locations were identified with the following
objectives;
To determine the baseline soil characteristics of the study area and
To determine the impact of proposed project on soil characteristics
TABLE 3.14: SOIL SAMPLING LOCATIONS
Location
Code
Name of the
Location
Coordinates
Direction & Distance w.r.t Center of Block Latitude Longitude
S1 Ubkhal 23°34'12.21"N 72°37'38.06"E NE-10 Km w.r.t Chalada-Mansa
S2 Gozaria 23°28'37.23"N 72°33'24.14"E SE-3.9 Km w.r.t Chalada-Mansa
S3 Bilodra 23°31'4.20"N 72°38'59.62"E NNE- 3 Km w.r.t Charada
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S4 Dilwara 23°30'44.74"N 72°40'44.21"E NE-4.4 Km w.r.t Charada
S5 Palasar 23°42'3.38"N 72°16'32.18"E ENE -4.3 Km w.r.t Lanwa
S6 Dholasan 23°24'15.21"N 72°20'31.35"E N-1.9 Km w.r.t Linch Extn-I
S7 Ridrol 23°27'52.92"N 72°40'22.25"E ESE -8.3 Km w.r.t Mansa
S8 Fatepura 23°25'50.10"N 72°38'11.60"E SE-5.7 Km w.r.t Mansa
S9 Kherva 23°32'40.63"N 72°26'39.67"E SW-1.7 Km w.r.t East Sobhasan
S10 Lagnaj 23°27'2.82"N 72°29'56.61"E NNW – 2.4 Km w.r.t Langhnaj-Wadasama
S11 patan 23°50'0.80"N 72° 7'20.57"E ENE-8.9 Km w.r.t Patan
S12 Rupal 23°41'8.83"N 72°20'29.62"E NNW-3.8 Km w.r.t North Sobhasan Ext I
S13 susar 23°38'52.11"N 72°13'41.66"E N-2.3 Km w.r.t Balol Ext I
S14 Chandrumana 23°45'7.66"N 72° 0'52.22"E SW-5.4 Km w.r.t Patan
S15 Ranuj 23°45'18.36"N 72°13'18.58"E NE-5.3 Km w.r.t Lanwa Ext-1
S16 Linch 23°29'43.65"N 72°22'17.26"E NNE-2.1 Km w.r.t Warosan
S17 Modhera 23°35'14.80"N 72° 8'18.66"E NNE-8.4Km w.r.t Becharaji
S18 Kungher 23°48'0.64"N 72° 3'43.69"E NNE -2.1 km w.r.t Patan
S19 Indrap 23°30'51.57"N 72° 8'33.72"E NNE-1.1Km w.r.t Becharaji
S20 Nani Rantej 23°24'45.59"N 72°12'18.84"E WSW-6.2 Km w.r.t North Kadi Ext (New)
The study area map covering the Soil sampling station is depicted in Figure – 3.21
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Figure –3.22: Map Showing Soil Sampling Stations
3.10.3 Presentation of Results
The soil quality at the specified location during the study period is tabulated as Table-3.15 ((a)-3.15(d).
TABLE 3.15 (a) - SOIL ANALYSIS RESULTS
Soil Sampling Stations
S.No Parameters Test Method S1 S2 S3 S4 S5
1 pH (1:5 Suspension) IS -2720(Part 26) 1987 (RA
2016) 6.92 6.57 6.86 6.92 6.59
2 Moisture, % IS -2720(Part 2) 1987(RA
2015) 1 0.86 1.23 1.15 1.17
3 Porisity, % IS -2720 (Part 36) 33.8 31.7 33.6 28.7 35.7
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TABLE 3.15(b) - SOIL ANALYSIS RESULTS
4 Water Holding Capacity,% Soil Chemical Analysis By
M. L. Jackson 25.8 26.8 19.9 32.4 27.1
5 Permeability, cm/hr Soil Chemical Analysis By
M. L. Jackson 1.3 0.14 1.4 0.90 1.1
6 Cation Exchange Capacity,
m.eq/100g
IS -2720(Part 24) (RA
2015) 9.63 28.6 11.4 17.1 21.6
7 Electrical conductivity,
mS/cm (1:5 Suspension) IS -14767:2000 (RA 2016) 0.246 0.205 0.13 0.217 0.134
8 Exchangeable Calcium as
Ca, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 4 7.8 72.8 38.9 1.07 1.03
9 Exchangeable Magnesium as
Mg, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 5 9.2 10.6 11 12.9 11.3
10 Exchangeable Sodium as
Na, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 6 3.05 6.15 5.96 4.55 4.04
11 Potassium as K, Kg/ha FAO Chapter 3,
ABCTL/SOIL/SOP 7 1040 1621 2283 2051 2179
12 Texture Classification IS -2720(Part 26) 1987(RA
2011)
Silt
Loam Clay
Silt
Loam
Silty
Clay
Loam
Silty
Clay
Loam
13 Sand (%)
Robinson Pipette Method
22.6 29.6 23.1 17.4 19.6
14 Clay (%) 24.1 48.2 19.6 30.4 28.4
15 Silt (%) 53.3 22.2 57.3 52.2 52
16 Sodium Absorption ratio By Calculation 3.31 3.01 3.77 5.45 5.16
17 Available Phosphorous as P,
Kg/ha FAO Chapter 3, ABCTL/SOIL/SOP2 16.6 22.8 29.6 18.7 31.7
18 Available Nitrogen as N,
Kg/ha FAO Chapter 3, ABCTL/SOIL/SOP11 215 198 263 241 230
19 Total Nitrogen as N, Kg/ha IS-14684:1999, Reaff:2008 284 263 327 316 357
S.No Parameters Test Method S6 S7 S8 S9 S10
1 pH (1:5 Suspension) IS -2720(Part 26) 1987 (RA
2016) 7.03 6.84 6.49 6.96 7.48
2 Moisture, % IS -2720(Part 2) 1987(RA
2015) 0.98 1.31 1.08 1.18 1.05
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TABLE 3.15(c) - SOIL ANALYSIS RESULTS
3 Porisity, % IS -2720 (Part 36) 32.1 36.4 30.8 28.8 26.8
4 Water Holding Capacity,% Soil Chemical Analysis By
M. L. Jackson 32.6 35.1 32.8 25.8 19.6
5 Permeability, cm/hr Soil Chemical Analysis By
M. L. Jackson 1.7 1.3 1.8 1.2 2
6 Cation Exchange Capacity,
m.eq/100g
IS -2720(Part 24) (RA
2015) 12.6 18.7 24.8 26.9 21.8
7 Electrical conductivity,
mS/cm (1:5 Suspension) IS -14767:2000 (RA 2016) 0.246 0.142 0.672 0.078 0.606
8 Exchangeable Calcium as
Ca, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 4 4.51 9.85 35.5 33.1 41.7
9 Exchangeable Magnesium as
Mg, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 5 8.95 7.3 10.7 12.15 12.1
10 Exchangeable Sodium as
Na, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 6 5.2 4.15 5.28 10.3 10.7
11 Potassium as K, Kg/ha FAO Chapter 3,
ABCTL/SOIL/SOP 7 1852 1688 1618 1892 3649
12 Texture Classification IS -2720(Part 26) 1987(RA
2011)
Silt
Loam
Silty
Clay
Loam
Loam Clay
Loam Loam
13 Sand (%)
Robinson Pipette Method
24.1 18.4 32.4 27.2 27.1
14 Clay (%) 21.6 24.6 28.6 35.1 26.8
15 Silt (%) 54.3 57 39 37.7 46.1
16 Sodium Absorption ratio By Calculation 6.35 4.49 3.48 6.85 6.53
17 Available Phosphorous as P,
Kg/ha FAO Chapter 3, ABCTL/SOIL/SOP2 13.7 20.7 17 41.8 36.9
18 Available Nitrogen as N,
Kg/ha FAO Chapter 3, ABCTL/SOIL/SOP11 236 207 263 310 284
19 Total Nitrogen as N, Kg/ha IS-14684:1999, Reaff:2008 309 271 352 407 391
S.No Parameters Test Method S11 S12 S13 S14 S15
1 pH (1:5 Suspension) IS -2720(Part 26) 1987 (RA
2016) 7.11 6.89 6.53 6.64 6.84
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2 Moisture, % IS -2720(Part 2) 1987(RA
2015) 5.14 1.36 1.2 1.03 0.93
3 Porisity, % IS -2720 (Part 36) 27.5 34.1 36.6 33.9 38.2
4 Water Holding Capacity,% Soil Chemical Analysis By
M. L. Jackson 25.4 31.8 36.9 32.4 28.7
5 Permeability, cm/hr Soil Chemical Analysis By
M. L. Jackson 1.9 0.23 0.21 0.26 0.18
6 Cation Exchange Capacity,
m.eq/100g
IS -2720(Part 24) (RA
2015) 33.9 32.8 30.7 36.1 30.9
7 Electrical conductivity,
mS/cm (1:5 Suspension) IS -14767:2000 (RA 2016) 0.184 0.343 0.508 0.809 0.336
8 Exchangeable Calcium as
Ca, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 4 9.14 7.06 12 2.9 108
9 Exchangeable Magnesium as
Mg, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 5 6.84 12.25 14.3 12.3 12.18
10 Exchangeable Sodium as
Na, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 6 3.69 5 8.82 8.68 9.85
11 Potassium as K, Kg/ha FAO Chapter 3,
ABCTL/SOIL/SOP 7 914 1816 2102 3175 2293
12 Texture Classification IS -2720(Part 26) 1987(RA
2011)
Clay
Loam Clay Clay Clay Clay
13 Sand (%)
Robinson Pipette Method
32.4 25.8 29.6 29.7 26.7
14 Clay (%) 38.6 51.8 47.6 58.4 55.1
15 Silt (%) 29 22.4 22.8 11.9 18.2
16 Sodium Absorption ratio By Calculation 4.13 5.10 7.70 9.97 4.02
17 Available Phosphorous as P,
Kg/ha FAO Chapter 3, ABCTL/SOIL/SOP2 25.8 54.7 41.8 62.5 38.4
18 Available Nitrogen as N,
Kg/ha FAO Chapter 3, ABCTL/SOIL/SOP11 315 346 294 311 254
19 Total Nitrogen as N, Kg/ha IS-14684:1999, Reaff:2008 477 505 399 425 384
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TABLE 3.15(d) - SOIL ANALYSIS RESULTS
S.No Parameters Test Method S16 S17 S18 S19 S20
1 pH (1:5 Suspension) IS -2720(Part 26) 1987 (RA
2016) 6.73 6.89 6.78 7.03 6.99
2 Moisture, % IS -2720(Part 2) 1987(RA
2015) 1.47 1.33 1.21 0.98 1.18
3 Porisity, % IS -2720 (Part 36) 26.8 33.1 39.6 30.6 32.8
4 Water Holding Capacity,% Soil Chemical Analysis By
M. L. Jackson 14.4 35.1 29.6 19.1 17.5
5 Permeability, cm/hr Soil Chemical Analysis By
M. L. Jackson 0.41 0.18 0.16 0.58 0.63
6 Cation Exchange Capacity,
m.eq/100g
IS -2720(Part 24) (RA
2015) 9.66 32.8 34.1 25.6 31.6
7 Electrical conductivity,
mS/cm (1:5 Suspension) IS -14767:2000 (RA 2016) 0.107 0.239 0.599 0.079 0.154
8 Exchangeable Calcium as
Ca, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 4 154 19.88 105 3.21 5.51
9 Exchangeable Magnesium as
Mg, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 5 11.92 11.43 13.41 14.8 7.98
10 Exchangeable Sodium as
Na, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 6 7.61 7.14 8.8 4.43 2.5
11 Potassium as K, Kg/ha FAO Chapter 3,
ABCTL/SOIL/SOP 7 1809 2327 3237 2740 1685
12 Texture Classification IS -2720(Part 26) 1987(RA
2011)
Sandy
Loam Clay Clay
Silty
Clay
Silty
Clay
13 Sand (%)
Robinson Pipette Method
55.6 22.8 27.2 12.2 9.6
14 Clay (%) 17.1 65.1 69.3 47.5 49.5
15 Silt (%) 27.3 12.1 3.5 40.3 40.9
16 Sodium Absorption ratio By Calculation 2.64 5.71 3.62 4.68 3.05
17 Available Phosphorous as P,
Kg/ha FAO Chapter 3, ABCTL/SOIL/SOP2 21.8 32.8 44.7 30.6 58.7
18 Available Nitrogen as N,
Kg/ha FAO Chapter 3, ABCTL/SOIL/SOP11 255 300 274 255 326
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3.10.4 Observations:
It has been observed that the pH of the soil is ranging from 6.49 to 7.48. Moisture found in the range from
0.86 to 5.14%. Conductivity of the soil ranges from 0.078 to 0.809 mS/cm. Texture of the soil in the
selected locations of study area were observed to be Clay and Silty Clay in nature. The potassium content
varies from 914 to 3649 kg/ha. Exchangeable Sodium content varies from 1.66 to 10.7 m.eq/100g.
Exchangeable calcium and Exchangeable magnesium were found in the range between 2.9 to 154
m.eq/100g & 6.84 to 14.8 m.eq/100g respectively.
19 Total Nitrogen as N, Kg/ha IS-14684:1999, Reaff:2008 375 410 532 391 482
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Fig 3.23 Soil texture Classification
The infiltration rate of the soil depends on the soil texture of the area. Soil texture depends on the relative
proportion of Sand, Silt and Clay. In Mehsana, Ahmedabad and Gandhinagar districts predominant soil
group is of Loamy soil. It has been observed that infiltration rate in the loamy soil is high.
The soils in the Patan district are generally sandy loam type with grey to brown colour. They are generally
deep and have moderate to good permeability and drain ability. In the western part of the district the sols
are alkali type and saline. They are typically deep, grey, calcareous sandy loam of very low permeability.
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BILODRA PALASAR
PATAN RUPAL
FATEHPURA KHERVA
Figure 3.24 Soil Sampling locations of the study area
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3.11 Biological Environment
3.11.1 Introduction
Natural flora and fauna are important features of the environment. They are organized into natural
communities and are sensitive to outside influences. Integrating ecological thinking into the planning
process is urgent need in the context of deterioration of natural environments, which is unwanted but
direct consequence of development. Biological communities, being dependent on the condition and
resources of its location may change if there is change in the environment. Hence change in the status
of flora fauna are an elementary requirement of Environment Impact Assessment Studies, in view of the
need for conservation of environmental quality and biodiversity. Information on flora fauna was collected
within the study area.
3.11.2 Reconnaissance of Study Area
The study area is dominated by scrub, small trees and a few large trees along with agricultural fields. The
study area has been defined as an area covering the buffer distance of 10 km around each mining lease.
The field observations on vegetation was made by surveying at different locations with the help of “Flora
of Gujarat by G. L. Shah, flora, topographic maps, forest working plan identification of those plants which
form dominant vegetation, native plants which prevails flowering period. Actual counts of birds were made
following the standard survey technique. Observation were made during a walk through in the chosen
transect for sighting birds and animals. The number of animals and birds observed in 1km stretch of the
site were directly counted and listing was made. Birds were noted and identified with the help of binocular
and standard field identification guides. Other animals were directly counted from amongst the vegetation,
bushes and roadside fields. Flora fauna detail and other Agriculture information has been collected during
the study period.
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Fig3.25: Sampling Locations of Ecology and Biodiversity study area
3.11.3 Assessment of Flora
The list of floral species is prepared based on visual observation during site visit and through review of
site literature and secondary data available with various government offices is referred for identifying rare
or endangered species in the region.
Table 3.16: List of Flora in the study Area
S.No. Scientific Name Local Name Status Districts
Mehsana Patan Ahmedabad
Gandhinagar
TREES
1. Acacia nilotica Baval C √ √ √ √
2. Acacia Senegal Gorad C √ √ √ √
3. Alangium lamarkii Ankol C √ √ √ √
4. Albizia lebbek Siris C √ √ √ √
5. Azadirachta indica Limdo C √ - √ √
6. Butea monosperma
Khakhro C √ - √ -
7. Casearia tomentosa
Umbh C √ - √ -
8. Cassia fistula Amaltas C √ √ √ √
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9. Cassia siamea Kasid C √ √ √ √
10. Cordial dichotoma Gundo C √ √ √ √
11. Dalbergia sisoo Sissoo C √ √ √ √
12. Delonix regia Gulmohar C √ √ √ √
13. Diosphros montana
Dheki C √ √ √ √
14. Emblica officinalis Amla C √ √ √ √
15. Ficus benghalensis
Vad C √ √ √ √
16. Ficus religiosa Pipalo C √ √ √ -
17. Ficus glomerata Gular C √ √ √ -
18. Holoptelea integrifolia
Charal C √ √ √
19. Gymnosporia montana
Viklo C √ √ √ √
20. Ficus infectoria Pipli C √ √ √ √
21. Madhuca latifola mahuda C √ √ - √
22. Mangifera indica Ambo C √ √ - √
23. Mimusops hexandra
Rayan C √ √ - √
24. Peltophorum ferruginium
Asopalav C √ √ √ √
25. Zizyphus mauritiana
Bordi C √ √ √ √
26. Achyrantus aspers Aghedo C √ - √ -
27. Adhatoda vasica Ardusi C √ - √ -
28. Balanites rosburghii
Ingor C √ - √ -
29. Calotropis procera Nano Akdo C √ √ √ √
30. Capparis aphylla Kerdo C √ √ √ √
31. Cassia auriculata Aval C √ √ √ √
32. Cassia tora Pumvadiyo/Kawaria
C √ √ √ √
33. Holarrhena antidysenterica
Kado C √ √ √ √
34. Jatropha cureas Ratanjyot C √ √ - √
35. Tecoma stans Vasant C √ √ - √
36. Vitex negundo Nagod C √ √ - √
37. Zizyphus nummularia
Chanibor C √ √ - √
HERBS
38. Acalypha indica Dadarjo C √ √ √ √
39. Achyranthus aspera
Anghedi C √ √ √ √
40. Aerva lanata Gorakh ganjo C √ √ √ √
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41. Aeschynomene indica
Budda pea C √ √ √ √
42. Aeschynomene procumbens
- C √ √ √ √
43. Hygrophila auriculata
Kantashelio C √ - √ √
44. Amaranthus spinosus
Katanudant C √ - √ √
45. Argemone mexicana
Darudi C √ - √ √
46. Bacopa monnieri Bam C √ √ √ -
47. Blumea eriantha Kapuriyo kalhar
C √ √ √ -
48. Brassica juncea Rai C √ √ √ -
49. Brassica nigra Jangliraj C √ √ √ -
50. Cassia tora Kunvandio C √ √ √ -
51. Catharanthus roseus
Barmasi C √ √ √ -
52. Celosia argentea Lampdi C √ √ √ √
53. Chenopodium album
Chilni Bhaji C √ √ √ √
54. Colocasia esculenta
Pattarveliya C √ √ √ √
55. Leucas aspera Kubi C √ √ √ √
56. Lycopersicum esculentum
Tamata Cu √ √ √ √
57. Martynia diandra Vinchu C √ √ √ -
58. Musa paradisiaca Kela Cu √ - √ -
59. Ocimum basilicum Damro C √ - √ -
60. Ocimum sanctum Tulsi C √ √ √ √
61. Oldenlandia corymbosa
Parpat C √ √ √ √
62. Physalis minima Rasbhari C √ √ √ -
63. Typha angustata Ramban C √ √ √ -
64. Polygonum glabrum
Kamole C √ √ √ -
65. Portulaca oleracea Motiluni C √ √ √ √
66. Solanum nigrum Piludi C √ √ √ √
67. Xanthium strumarium
Chhota Gokhru
C √ √ √ -
CLIMBERS
68. Bougainvillea spectabilis
Bouganvel C √ √ √ √
69. Coccinia grandis Ghiloda C √ √ - √
70. Cucurbita maxima Kolu C √ - - √
71. Dregia volubilis Nilsoti C √ - - √
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72. Luffa acutangula Turiya Cu √ √ - √
73. Mimordica charntia Karela Cu √ √ √ √
74. Mucuna pruriens Kuvech C √ √ √ √
75. Quisqualis indica Madhumalti C √ √ √ √
76. Tinospora cordifolia
Gulvel C √ √ √ √
TWINNERS
77. Abrus precatorius Chanothi C √ √ - √
78. Cuscuta chinensis Amarvel C √ √ - √
79. Dioscorea pentaphylla
Kuvel C √ √ - √
80. Ipomoea quamoclit Kamlata C √ - √ √
81. Teramnus labialis Valio velo C √ - √ √
82. Rhynchosia minima
Nani Kamal Vel
C √ - √ √
GRASSES
83. Cymbopogon martini
Roicha ghas C √ √ √ √
84. Cynodon dactylon Darb C √ - - -
85. Dendrocalamus strictus
Narvans C √ - - -
86. Paspalidium flavidium
Gorju C √ - - -
87. Saccharum officinarum
Sherdi C √ √ √ √
(√) flora observed during primary survey; (-) flora absent during primary survey
Source: District Gazetteers & Field Survey by FAE. Where C: common species & Cu:- cultivated commercially
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Fig3.26: Sampling of the study Area
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Fig3.27: Vegetation of the study Area
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Fig3.28: Mushrooms are found in the study area
3.11.4 Vegetation of Study Area
Most of the vegetation is aggregated on agricultural boundaries, road side plantation, private land and
social forest area. The study area mainly comprises of terrestrial and aquatic ecosystem. Vegetation
around the study area comprises of mainly thorny deciduous and bushy vegetation. The study area
comprises of tropical dry deciduous forest vegetation characterized by Acacia nilotica, Phoenix sylvestris,
Butea monosperma, Ficus religiosa, Delbergia sissoo, Pithecellobium ducle, Aegle marmelos, etc. are
the predominant plant species. The main agriculture crops are Wheat, Castor and Cotton.
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3.11.5 Assessment of Fauna
The faunal species were observed in association with floral components or along the water bodies.
Mammal species included Cows, Buffaloes and Goats domesticated by the villagers. During the site visit
and personal communication with local people it was recorded that Indian Fox, Nilgai, Common Monkey,
Wild Pig were observed in the study area. Nilgai and other domestic animals are mainly damaging
agriculture crops. Aves like Pavo cristatus falls under Schedule I of Wildlife Protection Act was observed
in study area.
The area supports varies habits viz. open space, scrub-land, agricultural fields, wetlands and human
settlements. A faunal enlisting of mammals, reptiles and birds with their scientific names, common names
and the schedule (as per Wildlife Protection Act, 1972) to which they belong is presented in Table 3.17
Total 5 species of mammals, 6 species Reptiles, and 34 species of avifauna were reported in the study
area. Cattle egrets were found in symbiotic association with grazing animals. Common Crow, Pigeon,
Egret were most conspicuously observed hovering over the inundated agriculture fields and barren lands.
The Avifauna includes the Kingfisher, Myna, Parrot, Black Drongo, Parakeets, and Kingfisher etc. Pond
Heron and Egrets were observed near road side ditches, rivers and near water ponds. The vegetation
around these water bodies provides nesting places for these birds. Kingfisher was often observed
perching on electric wires overhanging water or flying swiftly over the water bodies. No rare or threatened
faunal species are present at proposed site and surrounding area except Pavo cristatus (Indian peafowl),
Schedule I species of Wildlife Protection Act, 1972 was observed in study area.
A faunal enlisting of mammals, reptiles and birds with their scientific names, common names and the
schedule (as per Wildlife Protection Act, 1972) to which they belong is presented in Table
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Indian Myna Red Wattled Lapwig
Cattle Egret Peacock
Indian Bubbler Indian Parrot
Fig3.29: Avifauna Found in the study area
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Fig: 3.30 Common Myna found in the study area
Fig 3.31: Pond found in the study area
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Table 3.17: Fauna observed in Study Area
S.No. Scientific Name Common Name Schedule/IUCN Category
BIRDS-
1. Acridotheres ginginianus Bank Myna IV
2. Dicrurus adsimilis Black drongo IV
3. Pseudibid papilosa Black Ibis IV
4. Elanus caeruleus Blackwinged Kite IV
5. Columba livia Blue rock Pigeon IV
6. Bulbulcus ibis Cattle Egret IV
7. Acridotheres tristis Common Myna IV
8. Pavo cristatus Common Peafowl I
9. Tringa hypoleucos Common Sandpiper IV
10. Centropus sinensis Crow pheasant IV
11. Corvus splendens House Crow V
12. Passer domesticus House Sparrow IV
13. Hirundo rustica House Swallow IV
14. Apus affinis House swift IV
15. Saxicoloides fullicata Indian Robin IV
16. Coracias benghalensis Indian Roller IV
17. Edynamys scolopacea Koel IV
18. Ardea alba Large Egret IV
19. Phalacrocorax niger Little Cormorant IV
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20. Egretta garzetta Little Egret IV
21. Copsychus saularis Magpie Robin LC
22. Milvus migrans govinda Pariah kite IV
23. Ardeola grayii Pond Heron IV
24. Nectarinia asiatica Purple Sunbird LC
25. Streptoplia tranquebarica Red Turtle Dove IV
26. Pycnontus cafer Red Vented Bulbul IV
27. Vanellus indicus Red wattled Lapwing IV
28. Psittcula krameri Rose ringed Parakeet IV
29. Merops orientalis Small green bee-eater IV
30. Egretta intermedia Smaller Egret IV
31. Steptopedila chinensis Spotted Dove IV
32. Orthomus sutorius Tailor Bird IV
33. Halcyon smyrensis White breasted Kingfisher
IV
34. Threskiornis aethiopica White Ibis IV
REPTILES
35. Naja naja Cobra II
36. Vipera ruselli Russel’s viper II
37. Echnis carinatus Saw scaled viper LC
38. Bungarus caeruleus krait LC
39. Ptyas mucosus Rat Snake IV
40. Eryx johnii Red Sand boa IV
MAMMALS
41. Presbytis entellus Common Langur II
42. Boselaphus tragocamelus Nilgai LC
43. Herpestes edwardsii Mongoose IV
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44. Funambulus pennati Palm squirrel LC
45. Lepus nigricollis Black napped Hare LC
46. Rattus sp. Rat LC
Source: District Gazetteers & Field Survey by FAE.
I,II,III,IV & V are Scheduled of Indian Wildlife Protection ACT, 1972.
Least Concern, Endangered, Near Threatened, Vulnerable are the status assigned by IUCN.
Fig3.32: Nilgai (Boselaphus tragocamelus) found in the Cotton crop field of Study Area
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Fig 3.33 Orchards of pomegranate found in the study area
Fig 3.34: Cattle Egret found in the study area
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3.11.6 Aquatic Ecology
Establishment of biological status of an aquatic ecosystem is an essential pre-requisite to assess the
impacts of existing as well as proposed developments in the surrounding region. The best indicators of
environmental quality for a particular environmental condition are the biological species, viz.
phytoplankton and zooplankton. With a view to conserve the environmental quality and safety of natural
flora and fauna, studies on biological aspects of the ecosystem is of priority in an environmental impact
assessment study. These parameters serve as an inexpensive and efficient indicator of aquatic
ecosystem health for the presence of these indicator organisms depend on physico-chemical
characteristics of water such as pH, Conductivity, Nutrients, BOD, Alkalinity etc. and also type of water
body viz. canal/rivers, lakes, and sea.
3.11.6.1 Sampling Procedure
Sampling was done according to the parameters considered for the present study of above referred
communities. They are Phytoplankton cell count, Zooplankton standing stock and Macro benthic biomass
and population status.
Phytoplankton
Polyethylene bucket was used for sampling surface water for the estimation of phytoplankton cell count.
Samples were preserved in Lugol's iodine.
Zooplankton
Zooplankton samples were collected by passing known volume of water through Heron Tranter net (mesh
size 0.33 mm, mouth area 0.25 m2). After collection, samples were preserved in 5% buffered
formaldehyde.
3.11.6.2 Method of Analysis
Phytoplankton
The samples were stored in dark for a few days there by allowing cells to settle at bottom. At the time of
analysis, settled cells were transferred into a Sedgwick rafter slide/drop method. Enumeration and
identification of phytoplankton were done under a compound microscope
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Fig 3.35: Aquatic Sampling location of the study area
Zooplankton
Volume (biomass) was obtained by displacement method. The samples were analyzed under a Stereo
microscope for standing stock of representative samples
3.11.6.3 Species Diversity
In order to calculate species diversity, quantitative data were analyzed by the Shannon-Weiner index (H=
Σ pi ln pi where pi = ni/N).The Shannon-Weiner index shows diversity in any ecological communities, and
it is important to comment on the seasonal as well as spatial fluctuations. For this reason, index value is
important for expressing diversity in ecosystem management. The low index value meant that the most
unequal proportion of species. The Shannon-Weiner index gave higher values when the proportions of
species in a sample were close to each other. It was seen that the Shannon-Weiner index was not
affected by the number of species. In this respect, the Shannon- Weiner index has specific importance
in the expression of equal proportions of groups of organism in a sample rather than the total number of
individuals. The positive correlation appeared only when organisms show homogeneous distribution in
the total abundance. Thus H may give somehow contradictory results concerning the tropic status of an
aquatic ecosystem. The value of species diversity H is often found to fall between 1.0 and 6.0, and the
maximum diversity of a sample is H max when all species area equally abundant. Higher index values
express species higher diversity, but do not indicate the trophic status of an aquatic ecosystem. The
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number of species and number of individuals in a community is measure of species diversity which
depends on stability of the habitat.
The biological species specific for a particular environmental conditions are the best indicators of
environmental quality. This includes different biological species such as phytoplankton, zooplankton and
bacteria. Diatoms, desmids and dinophycean members are indicative of clean water conditions.
Increasing dominance of diatoms, ciliates, flagellates, chlorophycean and cyanophycean species
indicates progressively increasing trophic conditions. Presence of Euglenophyceae indicates high
eutrophic conditions.
Planktonic rotifers are usually more abundant in fresh water than estuarine waters. It is believed that
when crustacean and insect out number other groups the situation reflects the enriched organic
conditions of water. Thus, of certain organisms help in classifying water body in trophic levels on knowing
its physico-chemical characteristics. The most dominant macrophytes are Phragmites karka, Arundo
donax, Alternantha sessilis, Cyperus iria, Hydrilla verticillata and Nymphoides cristrat.
The plankton samples were collected by using plankton net. The filamentous algae and debris were
avoided by filtering through the plankton net. The collected sample was condensed to 100 ml by filtration
and the samples were preserved using pinch of Rose Bengal and 10 ml of 4% formaldehyde solution.
For the measurement of frequencies of various forms of Phytoplankton and Zooplankton, one drop of the
sedimented plankton was mounted on a micro-slide, as many as 20 different microscopic fields situated
at more or less even distances from each other were examined, and numbers of individual organisms
are counted. It should also be noted that diversity is also susceptible to other parameters such as turbidity,
colour, nutrients and flow rates etc., particularly in rivers. A widely accepted ecological concept is that
community with larger number of species i.e. with high diversity will have high stability that can resist
adverse environmental factors.
Phytoplankton group reported from three locations having dominance of bacillariophyceae and
cyanophyceae followed by chlorophyceae and euglenophyceae members. About 10 species of
phytoplankton were reported from three locations as shown in table 3.17.
Zooplankton about 6 zooplankton species are recorded from all the sampling locations. The list of
plankton recorded in fresh water bodies in study area during study period as given in table 3.18
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TABLE 3.18 - List of Phytoplankton species found in the study area
S.No. Family Phytoplankton Species
1. Bacillariophyceae Navicula sp
Diatoma sp
Synedra sp
Cyclotella sp
Gomphonema sp
Nitischia sp
2. Cyanophyceae Chlorella sp
Scenedesmus sp
Nostoc Sp
3. Chlorophyceae Merismopidia sp
4. Euglenophyceae Euglena sp
TABLE 3.19 - List of Zooplankton species found in the study area
Sl.No. Family Zooplankton Species
1. Rotifera Brachinous sp
2. Arthropoda Nauplius sp
Acroperus sp
Macrothrix sp
Ceriodaphnia sp
Simocephalus sp
Table 3.20: Shannon diversity Index of Phytoplankton and Zooplankton
Sl. No. Location Phytoplankton Zooplankton
Count No/Lit Shannon Weiner Diversity Index
Count No/Lit
Shannon Weiner Diversity Index
1. AE-1 710 1.82 766 1.91
2. AE-2 560 1.64 433 1.44
3. AE-3 420 1.58 836 2.15
4. AE-4 648 1.76 596 1.71
5. AE-5 590 1.78 608 1.98
6. AE-6 640 1.69 650 1.87
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*Ranges of Shannon-Wiener Diversity Index: 0<1: Indicate maximum impact of pollution 1-2: Indicate medium impact of pollution >2: Indicate minimum impact of pollution
Diversity of plankton depends on physico-chemical characteristics of water especially on trophic levels.
In oligotrophic water, diversity of plankton is high. While with increasing levels of pollution such as
mesotrophic and eutrophic condition diversity of plankton decreases. Shannon Wiener Index is a
measure of diversity of plankton, which takes into account the total count, and individual species count
in a water sample.
d = - ∑ (ni/n) log2 (ni/n)
Where,
d = Shannon Wiener Diversity Index
ni = Number of individual of each individual species in a sample
n = Total number of individual of all species in the sample
It should also be noted that the diversity is also susceptible to other parameters such as turbidity, colour
and flow rate particularly in hilly rivers. Thus the results should be interpreted with caution. A widely
accepted ecological concept is that communities with large number of species (i.e., with high diversity)
will have high stability that can resist adverse environmental factors. The maximum value of Shannon
Wiener Index of Phytoplankton for clean waters has been reported to be around 1.82, though it may differ
slightly in different locations given in table 3.19. Decrease in the value of index may thus be taken as
indicator of pollution. As shown in the table 3.19 and in figure of each plankton i.e phyto and zooplankton
is given in figure 3.36
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Figure 3.36: Shannon diversity Index of planktons
Total 11 nos. of phytoplankton were observed at all sampling locations in which Anabaena, Diatom and
Rhizosolenia were major dominant genera at almost all sampling locations. The highest cell count of
phytoplankton was recorded at Langhnaj village pond whereas lowest cell count was recorded at Kanpura
village pond. Total 12 nos. of zooplankton groups were observed at all sampling locations in which
Diaphanosoma, Daphnia and Cyclops were major dominant group in the all sampling locations. The
highest population of zooplankton was recorded at Bechrpura village pond whereas lowest at Kherva
village pond.
3.11.7 Conclusion
As per primary survey and secondary data referred, it can be concluded that the study area are diverse
and ecologically rich. The geography of Mehsana, Ahmedabad, Gandhinagar and Patan districts boasts
of having a wide variety of flora and fauna which are spread throughout its length and breadth. Some of
the important mammals found in the study area are Monkeys, nilgai, chitals, wild boar, four horned
antelope, Sambar deer, Asiatic wild ass, sloth beer and camels etc. A large number of other animals like
snakes, lizards, scorpions, bees, Jungle cat, Indian giant squirrel, wild dog, etc., are found in the study
area. Many kinds of birds are found here, such as: Greater flamingo, Peacock, Parrots, pheasants, geese,
sparrow, Booted Eagle, white throated Kingfisher, Spotted Dove, Green Sandpiper, Indian Robin, Painted
Strok, ducks and cranes, etc.
0
0.5
1
1.5
2
2.5
AE-1 AE-2 AE-3 AE-4 AE-5 AE-6
Shannon Weiner Diversity Index
Phytoplankton Zooplankton
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The natural vegetation are diverse with trees, along with understory herbs, shrubs and trees, lianas, and
ephiphytes Flora of Ahmedabad, Mehsana, Gandhinagar and Patan districts include a wide variety of
vegetation. A wide range of climatic condition facilitates the prevalence of many types of flora. Owing to
the arid climate flora possess a wide range of xerophytic vegetation.The predominant xerophytic
vegetation includes Acacia arabica (Babool), Acacia leucophloea, Capparis ophylla and Zizyphus
mauratiana etc. During the survey various species of flora are found in one of the largest dry deciduous
forests in the western region of India, including trees like: Terminalia catappa (Desi badam), Terminalia
arjuna (Arjun tree), Syzygium cumini (Jamun), Swietenia mahogany(Mahaneem), Psidium guajava
(guava), teak, Boswellia serrata, Anogeissus latifolia and Diospyros, etc. Therefore, as it is evident, the
proposed project area has an enormous store of flora and fauna. During survey of the study area, there
is no endangered and endemic fauna or flora found near the Study area.
3.12 Socio-economic Environment
The study of socio-economic aspects deals with social and cultural conditions, and economic status in
the study area. The socio-economic study provide information such as demographic structure, population
dynamics, infrastructure resources, status of human health and economic attributes like employment,
per-capita income, agriculture, trade, and industrial development in the study area. The aesthetics in the
study area represents tourist attraction and wildlife, historic and cultural monuments. The study of these
attributes helps in identification, prediction and evaluation of impacts on socio-economic and parameters
of human interest due to proposed project developments.
To assess impact of the project activity on socio-economic aspects, recent primary data collected from
field studies and Government agencies has been compiled to delineate the baseline socio-economic
profile in study area. The data generated in this study is classified as follows:
Administrative setup
Demographic structure
Infrastructure base
Economic attributes
Health status
Cultural attributes
Awareness and opinion of people about the proposed project
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Based on the primary and secondary data collected from villages and towns, the existing socio-economic
status have been analysed and details are appended below. The secondary data is collected from
Census Record (2011), District Census Handbook 2011 and Town Directory 2011.
3.12.1 Approarch and Methodology
For the purpose of establishing the social baseline for the project and undertaking the social impact
assessment, a phased participatory approach was adopted. Through this approach an attempt was made
to integrate the local understanding and perspective into the impact assessment process and
identification of the mitigation measures. The purpose of such an approach was to allow for:
The triangulation of the information available from secondary sources (available government and
non-government data) and through the information made available from the local community,
both qualitative and quantitative;
Primary sample survey in villages surrounding the Project site and formulation of the socio
economic baseline on the basis of a combination of primary and secondary qualitative and
quantitative data;
3.12.2 Methodology for Primary Data Collection
The socio-economic profile assessment related methodology included the following:
1) Scoping and defining the study area
Scoping and study area for socioeconomics assessment is defined in Section 1.4.3. The study area
considered for socioeconomic baseline assessment extending upto 10 km radius falling within the
study area. Table Presents methods and tools employed to undertake this study.
Table 3.21: Description of Tools employed for the Socioeconomic Assessment
Tools Description of the Methods/Tools
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Focus Group
Discussions
(FGD)
FGD helps in capturing the needs and expectations of diverse groups; hence an
effective method to cross validate data gathered and to also make it
representative for a larger population
Semi-structured meetings with community members and specific
groups (including village elder members, women group etc.) to
understand issues faced by relevant groups; including vulnerability,
perceptions of the project and needs in the area.
Key Informant
Interviews (KIIs)
KII method helps in undertaking focused and in-depth analysis and hence
effective as a tool to gather specific concerns etc.
Interviews with individuals who are informed members of the
community such as school teachers, healthcare professionals and
religious body representatives in the local area.
Perceptions of the people about the project related activities through
these interviews.
Surveys The Survey questions of semi-structured nature were used to generate
qualitative information
Sample surveys were undertaken with the affected families from the
setup of Project to understand their current livelihood patterns, to
understand how they perceive the community development activities by
the project.
Viilage
Resource
Mapping
Village Resource mapping and identifying settlement and livelihood patterns
and existing facilities (education, health, income generation, infrastructure etc.)
and changes in the recent years;
Community consultations at village level to understand how the village
perceived benefits and adverse impacts from the project;
Understanding further community needs of villages in the study area.
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2. Site Visit and Data Collection
FAE undertook site visit in the study area and consultations with village elders, women group
members, community members and government representatives as per the field visit plan developed
for the survey.For the primary data collection, structured questionnaires will be used by survey team.
This format will include all type of village information like demographic details, infrastructure details
etc.
3.12.3 Demography
As per Census of India 2011, the district has a total population of 20, 35,064 out of which males constitute
10, 56,520 and females 9, 78,544 of the total population. The district has an average literacy rate of 84.26
% with male literacy of 91.88 % and female literacy of 76.12 %. In Mehsana, about 11 per cent of
population is under 6 years of age. Population density of district is 462/ sq. km and ranked 10th among
the state. Sex ratio of the district is 926 and position in the state is 17th. The people of study area residing
in this part of the district largely belong to Hindu community comprising Brahmins and Jats. These people
prefer colorful attires especially in their cultural events. Chorno and Kediyu are the traditional wear for
gents and Chaniya Choli is for women. Gujarati is the main communicative language of the local people
along with Hindi as a second most popular local language. People are allured towards their folk dance &
music which runs in their vein. Garba, Rass, Garbi and Dandiya are some of the prime cultural dances
enjoying by the people of this part of the study area. With regards to Sex Ratio in Mehsana, it stood at
926 per 1000 male compared to 2001 census figure of 927. The average national sex ratio in India is 940
as per latest reports of Census 2011 Directorate. In 2011 census, child sex ratio is 842 girls per 1000
boys compared to figure of 801 girls per 1000 boys of 2001 census data.
In 2001 census, Mehsana had a population of 1,837,892 of which males were 953,842 and remaining
884,050 were females. Ahmedabad District population constituted 3.37 percent of total Maharashtra
population. In 2001 census, this figure for Patan District was at 3.63 percent of Maharashtra population.
There was change of 10.73 percent in the population compared to population as per 2011. In the previous
census of India 2011, Gandhinagar District recorded increase of 12.08 percent to its population compared
to 2011.
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Fig3.37: Distribution of Population in the Study Area
The initial provisional data released by census India 2011, shows that density of Mehsana district for
2011 is 462 people per sq. km. In 2011, Ahmedabad district density was at 419 people per sq. km. Patan
district administers 4,401 square kilometers of areas.
3.12.4 Literate Population:
Average literacy rate of Mehsana in 2011 were 83.61 compared to 75.22 of 2001. If things are looked
out at gender wise, male and female literacy were 91.39 and 75.32 respectively. For 2011 census, same
figures stood at 86.20 and 63.65 in Ahmedabad District. Total literate in Patan District were 1,502,645 of
which male and female were 847,499 and 655,146 respectively. In 2011, Gandhingar District had
1,188,224 in its district.
0
1000000
2000000
3000000
4000000
5000000
6000000
Mehsana Ahmedabad Patan Gandhinagar
Population
Total population Male population Female population
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Fig 3.38: Literacy rate of population in study area
3.12.5 Urban/Rural Population
As per the Census 2011 out of total population of Mehsana, 25.27% people lived in urban regions while
74.73% in rural areas. The total figure of population of urban population was 514,330 out of which 269,345
were males while remaining 244,985 were females. In rural areas of Mehsana, male population was
787,175 while female population was 733,559.
The average sex ratio in urban regions of Mehsana was 910 females per 1000 males. Also the Child (0-
6 age) sex ration of urban areas in Mehsana was 793 girls per 1000 boys. Thus the total children (0-6
age) living in urban areas of Mehsana were 53,958 which is 10.49% of total urban population. Similarly
the average sex ratio in rural areas of Mehsana was 932 females per 1000 males. The Child sex ratio of
rural areas in Mehsana was 857 girls per 1000 boys.
The average literacy rate in Mehsana for urban regions was 88.37 percent in which males were 93.52%
literate while female literacy stood at 82.81%. The total literate population of Mehsana was 1,502,645.
Similarly in rural areas of Mehsana, the average literacy rate was 81.97 percent. Out of which literacy
rate of males and females stood at 90.65% and 72.77% respectively. Total literates in rural areas of
Mehsana were 1,095,809.
0
500000
1000000
1500000
2000000
2500000
3000000
3500000
4000000
4500000
5000000
Mehsana Ahmedabad Patan Gandhinagar
Literates Population
Literacy Male literate Female Literate
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3.12.6 Social Structure
In the study area, as per 2011 census, 3.72% of the population belongs to Scheduled Castes (SC) and
6.92% to Scheduled Tribes (ST). Overall the data of social stratification reveals that the SC and ST % to
population is more than 10%, The SC and ST community are marginalized and they are at considered at
low level of social strata and calls for a special attention in Social Impact Management Plan for improving
their socio-economic status apart from preservation and protection of their art, culture and traditional
rights of livelihood.
Fig: 3.39 Social Structure of the study area
3.12.7 Occupational Structure
In Study area out of total population, 812,064 were engaged in work activities. 86% of workers
describe their work as Main Work (Employment or Earning more than 6 Months) while 14% were
involved in Marginal activity providing livelihood for less than 6 months. Of 812,064 workers
engaged in Main Work, 178,862 were cultivators (owner or co-owner) while 192,521 were
Agricultural labourer.
Main Workers: As per Census of India, all persons engaged in 'work' defined as participation in any economically
productive activity with or without compensation, wages or profit are workers. Those workers who had worked for
the major part of the reference period (i.e. 6 months or more) are termed as main workers.
Marginal Workers: Marginal workers were those who worked any time at all in the year preceding the enumeration
but did not work for a major part of the year, i.e., those who worked for less than 183 days (or six months).
0
100000
200000
300000
400000
500000
600000
700000
800000
Scheduled Castespopulation Person
Scheduled Castespopulation Male
Scheduled CastespopulationFemale
Scheduled Tribespopulation Person
Scheduled Tribespopulation Male
Scheduled Tribespopulation
Female
Social ProfileMehsanaAhmedabadGandhinagarPatan
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Cultivators: A person is classified as cultivator if he or she is engaged in cultivation of land owned or held from
Government or held from private persons or institutions for payment in money, kind or share. Cultivation includes
effective supervision or direction in cultivation. A person who has given out her/his land to another person or
persons or institution(s) for cultivation for money, kind or share of crop and who does not even supervise or direct
cultivation of land, is not treated as cultivator. Similarly, a person working on another person's land for wages in
cash or kind or a combination of both (agricultural laborer) is not treated as cultivator. Cultivation involves
ploughing, sowing, harvesting and production of cereals and millet crops such as wheat, paddy, jowar, bajra, ragi,
etc., and other crops such as sugarcane, tobacco, ground-nuts, tapioca, etc., and pulses, raw jute and kindred
fiber crop, cotton, cinchona and other medicinal plants, fruit growing, vegetable growing or keeping orchards or
groves, etc.).
Agricultural Laborers: A person who works on another person's land for wages in money or kind or share is
regarded as an agricultural labourer. She or he has no risk in the cultivation, but merely works on another person's
land for wages. An agricultural labourer has no right of lease or contract on land on which she/he works.
3.12.8 Infrastructure Facilities
It is observed that infrastructure facilities are poor in the project study area, which consists of education, health
care, drinking water facilities, communications and electrical facilities, etc. A review of infrastructure facilities
available in the area has been done based on available secondary data published in Gujarat state primary census
abstract,
3.12.8.1 Educational Facilities
The educational facilities are found to be moderate in the proposed project study area. There are Government as
well as Private primary, middle and senior secondary schools, are available near the study area.
3.12.8.2 Health Facilities in Rural Area
The national norm for population coverage per sub-center for tribal areas and for plain areas. Similarly, it is
recommended to have a Primary Health Centre (PHCs) and CHC (community Health Center) for population in the
range 80,000 to 1, 20,000. The number of PHCs served by a CHC is yet another indicator by which the physical
accessibility can be judged. As per national norms, 1 PHCs should be served by one CHC.
3.12.8.3 Drinking Water facility in the rural villages of the study area
One of the most important factors responsible for the emergence of a settlement is availability of water. Many water
sources such as wells, hand pumps, tube well, tank etc. are available in rural areas. In the villages under study,
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the main source of water is tank, followed by tap. The water of the hand-pump is used for drinking for animals,
bathing and household purposes. There are fewer ponds in the area and are mostly dry except for monsoon
months. The water from the ponds is generally not used by the villagers except for bathing animals.
3.12.8.4 Communication and Transport
Transport is an important part of India's economy but it is poor in comparison with international standards.
Since the economic liberalization of the 1990s, infrastructure development has progressed rapidly; today
there is a variety of modes of transport by land, water and air. However, India's relatively low GDP per
capita has meant that access to transport has not been uniform. Public transport remains the primary
mode of transport for most of the livelihood India. Buses take up over 90% of public transport in Indian
cities and serve as a cheap and convenient mode of transport for all classes of society. Services are
mostly run by state government owned transport corporations. Taxis can either be hailed or hired from
taxi-stands. Indian Railways provides an important mode of transport in India, transporting over 18 million
passengers and more than 2 million tonnes of freight daily across one of the largest and busiest rail
networks in the world.
3.12.8.5 Medical & public Health Facilities
During consultation, it was revealed that the existing health infrastructure and services in the study area
comprises of Primary Health Centre (PHC) and Health Clinics run by Private Practitioners. PHC exists in
only one village which is staffed with a medical officer supported by a pharmacist, a senior clerk and
helper (midwife) and caters to a population of only nearby villages. However, Maternity and Child Welfare
(MCW) Centre is available in three villages. Allopathic Hospital and Dispensary is not available in any of
the village. Hospital with surgical facilities is available. It was also informed that doctors and staff of PHCs
organizes general health check-up and awareness programme on maternal and child care, eye care and
immunization camps in the surrounding villages.
3.12.8.6 Existing Health Conditions and Concerns
During discussion, except routine cough, cold and fever, diarrhoea were reported common amongst
villagers in the study area which is due to open excreta and flies all around. Presidents of village
panchayat stated that due to lack of equipments, infrastructure as well as inadequate and poor coverage
of the existing health services, the people have to travel long distance which is time consuming and
expensive also. The analysis of secondary data based on census 2011 also revealed that people from
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95% villages in the study area are availing health facility within 5kms, 5-10kms and more than 10kms
distance from their village. There is a good awareness about pulse polio and vaccination among people
in the area. The private hospitals are equipped with better facilities than the PHC exist in the study area.
These private clinics mostly cater to the affluent class residents i.e., mostly belonging to middle income
group in the area and hence people are expecting health infrastructure with adequate staff shall be
provided by project authorities under welfare scheme/CSR plan on priority basis.
3.12.9 Public Consultations during Primary Survey
Public consultations were carried out by Team during the study period in Mehsana district. During
consultation, it was observed that people had concerns with respect to their existing socio economic
conditions like poor connectivity, bad condition of the village roads and water scarcity in summer etc.
With respect to the proposed project, the public had positive perception like better job opportunities as
well as infrastructural facilities and had welcomed the project. Figure 3.40 shows the survey and
stakeholder consultations at different locations in the study area.
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Fig 3.40: Socioeconomic Survey of the study area
3.12.10 Salient Observations of the Survey:
House pattern: It is notable that nearly 90% of the houses were pakka with good construction.
Employment: Main occupation of the people in the study area is agriculture and labour work.
The labours are getting daily wage in the range of Rs. 100-250, depending on type of work they
involved.
Fuel: The primary source of cooking fuel is LPG and coal is alternative fuel.
Sanitation: Toilet facility is one of the most basic facilities required in a house. The findings of
the survey shown that more than 90% of the households were having toilet facilities in their
houses. There was no proper drainage line in the villages, but soak-pit facilities were observed
in most of the villages surveyed. The overall condition of cleanliness was satisfactory.
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Drinking Water Facilities: Ground water is the major source of drinking water in the villages
wherein hand pumps, tap water and dug wells are installed. In some villages organized piped
water supply is also in operation.
Education Facilities: Most of the villages had education facilities in the form of Anganwadi and
Primary Schools. Higher education facilities were available in the range of 5-10 km. Colleges and
other diploma courses were available at Mangalore district place at a distance of 10- 20 km.
Transportation Facility: The public transport is primarily by public and private buses and auto-
rickshaws. Well established transportation is noticed between villages cities. Private vehicles like
bicycles and motor cycles are mostly used by villagers for transportation purpose.
Road Connectivity: Most of the roads are pucca and connecting to all villages with towns and
cities. Tar & Concrete roads were commonly seen inside the villages.
Communication Facilities: For communication purpose mainly mobile phones, newspaper &
post offices were seen in the villages.
Medical Facilities: There are few healthcare facilities available in the study area. In some of the
villages, primary health sub centres are available. Hospitals and other better medical facilities
are available in the range of 10-20 km at town/city place.
Electricity: Electricity is available in all the study villages and do not have frequent problem of
load shedding.
Market Facility: Study area is predominantly semi urban type. In villages, small shops are
available for daily needs. Weekly market facility is available in some villages. Wholesale markets
are available at town place.
Recreation Facilities: Temple, Samaj bhawan, Television and Radios are the main recreation
facilities in the study area. Newspaper/Magazine facilities were also used by villagers.
3.12.11 Economic Profile
Agriculture
Agriculture is the main occupation of the people in the study area. The water from bore wells and wells
is mostly used to carry out agricultural activities. Modern equipment and tractors are used to carry out
the agricultural work. During field visit it has been found that people are growing cotton, bajra, jowar,
castor, wheat, fennel seeds, mustard, cumin seeds, masoor, pigeon peas, sesame, potato, jowar,
tobacco etc in the form of cash crop. The horticulture crops such as cucurbits, cabbage and citrus are
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also grown.The villagers sell their agricultural products to Patan, Visnagar, Unjha, Mehsana,
Ambaliyasan, Mansa, Kadi and Katosan markets.
Fig 3.41: Animal Husbandry of the study area
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Animal Husbandry
Livestock grazing is the common occupation for the few people in the study area. The domestic animals
are cows, buffaloes, goats and camels which is used for catering milk and other agricultural facilities. The
vertinary doctors are available for medical checkup of animal on call basis.
Industries
There are many small, medium and large scale industries in the study area. Vegetable & Vanaspati,
paper & pulp industry, engineering, chemicals, pharmaceuticals, dairy products, oil and textiles sectors,
rubber & plastic articles, metals, repairing services and food & processing industries are some of the
major industries operating in the small scale sector in the study area. Emergence of investments in new
sectors such as Infrastructure, IT and Tourism has been observed during the last decade.
3.12.12 Cultural and Aesthetic Attributes
Study area of 10km from centre of development well does not involve any major place with religious,
archaeological and historical importance.
Festival Celebrated in the Study Area
They have their own set of customs and rituals in the study area. The main language spoken by the
people is Gujarati. The people celebrate Uttarayan - Kite festival and Navratri with people performing
Garba/folk dance. The Hindu and Jain communities, because of their religious beliefs, maintain a strong
tradition of vegetarianism in the daily cuisine.
3.12.13 Community Consultation:
Interaction with different village Sarpanch/Society Heads/ villagers was done to understand the socio-
economic issues of the region and their needs. It will be of profound importance to study the perception
as well as reaction of the community people towards the proposed project activity. In-depth interview with
President of selected Village Panchayat, discussion with Members and local people was done to gather
the existing baseline socio-economic information on a various parameters of Quality of Life. During
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discussion, issues related to employment generation, information flow, health and safety, social welfare
activity, temporary and permanent land requirement etc. were discussed.
Table 3.22: Potential Sources of Secondary Data to validate the Primary baseline data of EIA
Information Source
1. Air Environment
Temperature, Rainfall, Humidity, Wind
Speed, Wind direction and Seasonal wind
rose pattern.
Ambient Air Quality-24 hourly
concentration of PM2.5, PM10, SO2,NOx
and CO
Indian Meteorology department
Central Pollution Control Board
2. National River water quality monitoring
Programme
Central Pollution Control Board
3. State Forest Report
National Forest Vegetation Map
Forest Survey of India
4. Soil Sampling, Classification and
Characterization
Indian council of Agriculture
5. Topographical Surveys sheet Survey of India
6. National Wildlife database Wildlife Institute of India
7. Survey of Floral/Faunal Resources Botanical/Zoological Survey of India
8. Socioeconomic Census Department
District Gazetteers
Central Statistical Organisation
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Chapter 4
Anticipated Environmental Impacts
&
Mitigation Measures
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4.0 Anticipated Environmental Impacts & Mitigation Measures
4.1 Introduction:
The objective of the impact identification is to formulate Environmental Management Plan (EMP) to mitigate the probable negative impacts that might arise during the project activities to the maximum possible extent. Therefore, in order to come to a strategic EMP it is imperative to identify the possibilities at various project stages, impact type and affected environmental component, extent and severity. EIA is an activity designed to identify and predict the impact on the environment, on human health and ecology, taking into account the requirements of legislative proposals, policies, programs, operational procedures and to communicate information about the impact. The identification of the potential impacts during the drilling activity on various environmental components namely Air, Water, Soil etc., are discussed below:
Table 4.1 Key Potential Impacts of drilling Activities
Potential impacts Potential Environment Impacts for onshore activities
Potential Physical Environmental Impacts
Sedimentation Erosion Disturbance of sensitive areas Soil compaction and disturbance Groundwater disturbance Drainage alteration, surface seepage, drainage lines and
creek disturbance Hydrocarbon contamination Fire
Potential Biological Environmental Impacts
Disturbance to fauna including breeding seasons or migration paths
Noise and light disturbance Disturbance of rare and endangered flora and fauna and
threatened ecological communities Introduction of noxious weeds and vermin, exotic species,
flora and animal diseases Encroachment into quarantine areas Disturbance to habitats and vegetation communities
Potential Social Environmental Impacts
Disturbance to heritage sites Disturbance to archaeological sites Disturbance to scientific study sites Disturbance to tourism Public disruption Disturbance to pastoral or farming activities Disturbance to horticultural activities Disturbance to aesthetics (visual impact) Disturbance to ethnographic sites Third party access denial or creation
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Table 4.2 Impact Significance Criteria
Impact Significance Criteria
Major Adverse When the impact is of:
high intensity
high spread (regional) or moderate spread
high or moderate duration
Moderate Adverse When the impact is of
moderate intensity
high or moderate or low spread
high or moderate or low duration
Minor Adverse When the impact is of:
moderate or low intensity
low spread
moderate or low duration
Insignificant Adverse When the impact is of
low intensity
low spread
low duration
Beneficial When the impact are positive
A Number of techniques are available for identification of impacts. In the present case “Network Method” has been adopt for understanding the “cause-condition-effect” relationship between an activity and environmental parameters. Various activities and their likely impacts due to drilling have been identified and shown in the Table 4.3. The detailed list of activities and actions described earlier in this report has been taken into consideration for generation of cause-condition-effect network (i.e. chain of events). The idea was to account for the project activity and identify the types of impacts, which would initially occur. The next was to select each impact and identify the secondary and tertiary impacts, which induced as a result. This process was repeated until all possible impacts were identified. While identifying the impact networks for drilling operations in the study area all significant activities such as land acquisition, road/site clearance, drill site preparation and diesel generation set operation have been considered the availability of energy resource (oil/gas) the end product has been considered for the purpose of economic benefits.
The identified impacts for various components of environment viz. air, noise, water, land, biological and socio-economic are described respectively.
4.2 Impact assessment and mitigation measures
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This section discusses the possible impacts of the project activities on the existing environmental receptors, particularly on the environmental sensitivities of the area which get effected by the project. It discusses probable impacts during various phases of the project life cycle to the environmental receptors. Identification of impacts would help in delineating appropriate mitigation measures to reduce the adverse impact
Table-4.3: Activities – Impacts/Risks Interaction Environmental Sensitivities
Environmental Sensitivities
Impacts/ Risk
Physical Biological Socio-economic
Activities
So
il &
Sed
imen
ts
Wat
er R
eso
urc
e &
Qu
alit
y
Air
Qu
alit
y
Flo
ra
Fau
na
Res
erve
Fo
rest
/ Pro
tect
ed F
ore
st
Liv
ing
Co
nd
itio
n
Lo
cal E
con
om
y
Exi
stin
g O
il an
d G
as B
usi
nes
s
Tra
ffic
Haz
ard
s
On
site
Ris
ks (
Occ
up
atio
nal
Exp
osu
re)
Cu
ltu
re/ A
rch
aeo
log
ical
pla
ces
To
uri
sm /
Lei
sure
Lan
d U
se (
Mu
dfl
ats/
Ag
ricu
ltu
re)
Drilling Site Preparation
Physical Presence including Land acquisition/ Lease
Site Clearance
Site Preparation
Equipment Transportation
Campsite
Drilling Operation
Atmospheric emissions
Noise & Vibrations
Waste generation
Storage of Flammables
Well kick
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4.2.1 Air Environment:
The potential sources of air emissions at the well sites will be as follows:
Dust from earth works (during approach road and site preparation);
Emissions from DG sets;
Emissions from vehicles.
During the short period of site preparation mechanical shovels and earthmovers will be used for vegetation clearance, cut and fill and other site levelling activities. These activities could generate dust particles which will be mobilized by wind, and deteriorate the ambient air conditions. However, these activities will be only temporary and with the clay nature of the soil, the impact to ambient air quality would be within the close proximity of well site.
All the anticipated air emissions other than dust arise from combustion of hydrocarbons. The pollutants of concerns are NOx, SO2, CO and Particulate matter
4.2.1.1 Potential Impacts
Ambient air quality effects are normally assessed in relation to their potential to cause:
Health deterioration and nuisance in local communities;
Health deterioration amongst on-site workers; and
Damage to vegetation.
The gaseous emissions from the DG set will be controlled by efficient combustion of fuel in the DG set.
The impact on ambient air quality is assessed hereunder considering the following:
The air quality impacts have been predicted for the proposed drilling; and
Site-specific meteorological parameters have been recorded. Short-term 24 hourly GLC's incremental values were estimated using the site-specific meteorological data.
4.2.1.2 Fugitive Emissions
Air pollution during construction would be primarily due to fugitive emissions from vehicular movement, site preparation activities and material handling. Weathering of soil would take place as a result of clearing of vegetation, excavation and movement of heavy vehicles. The weathered soil generates dust due to re-entrainment during vehicular movement and equipment mobilization. Such dust emissions as experienced in other similar construction activities are of larger that 10μ (more than respirable range) and
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propagates to short distances. These emissions only have nuisance factor affecting workers at site. Use of dust masks would be adequate to mitigate impacts on workers.
Fugitive emissions in the form of material dust is expected during drilling operations (loading, unloading, handling of drilling fluid, chemical additives, cement and cement additives). Some fugitive emissions are also anticipated from storages of volatile chemicals and fuel at the site if the storages are not properly capped or are handled without due care. However, such emissions will not disperse widely and can only affect workers and people at site. Fugitive emissions during drilling operations are however not as significant as during site preparation. Fugitive emissions during drilling are not expected to travel beyond project boundaries. Workers working near fugitive emission sources are only susceptible which would be mitigated through use of PPEs in these areas.
4.2.1.3 Air Pollution Modelling
Prediction of impacts on air environment has been carried out employing mathematical model based on a steady state Gaussian plume dispersion model designed for multiple point sources for short term. In the present case, AERMOD dispersion model based on steady state gaussian plume dispersion, designed for multiple point sources for short term and developed by United States Environmental Protection Agency [USEPA] has been used for simulations from point sources.
4.2.1.4 Model Input data
Emission from DG sets:
The power requirements for the operation of the drilling is met by using diesel generator sets. Three generators of each1250 kVA are installed at the site. The cumulative power generating capacity of the 3 units is 3750 kVA of power at peak periods. The DG sets are primary contributor to air pollution at the drill site. The pollutants emitted by a DG set consists of Particulate Matter (PM), Sulphur-di-oxide (SO2), Nitrogen Oxides (NOx) and Carbon Monoxide (CO). Combustion of fuel in a DG set typically happens at high temperatures resulting in generation of considerable amounts of NOx. The SO2 concentration in emissions is dependent on the Sulphur content in fuel burnt and particulate matter consists of unburnt Carbon particles.
The emission from each of the power generator sets in the drilling rig will be due to combustion of diesel. For a particular drilling site during drilling operation, there will be 03 operating DG sets, as detailed in Table-4.4.
TABLE-4.4 Details of DG Sets
Location DG Capacity Operational Stand by Fuel Requirement
Drilling Site 1250 kVA 02 01 104 L/Hrs
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The operational DG sources are considered as source for the modelling. The emission from each of these diesel generators will be due to combustion of diesel.
Modelling Scenarios
Emissions from diesel generator sets will be continuous throughout the drilling operations. The main pollutants from diesel generator sets include Particulate Matter (PM), Sulphur-di-oxide (SO2), Nitrogen Oxides (NOx) and Carbon Monoxide (CO). As the fuel used is low sulphur HSD, insignificant amount of Particulate emissions and gaseous emissions are envisaged. The emission characteristics considered for the modelling exercise from DG generator sets are given in the Table–4.5
TABLE-4.5 Emission Characteristics- Model Inputs
Sr. No Particulars DG Set (3x 1250 kVA)
1. No. of engines and stacks 03
2. Height above ground level (m) 6.8
3. Diameter (m) 0.30
4. Gas temperature (°C) 427.86
5. Gas velocity (m/s) 11.785
6. Emission rate (g/s) 0.016 (PM), 0.04(SO2), 0.23 (NOx) & 0.05 (CO)
4.2.1.5 Presentation of Results
(a) Rupal Meteorological Station
The Maximum GLC’s results for PM, CO, SO2 and NOx are presented in Table-4.6 (a) the isopleths for
PM, CO, SO2 and NOx concentrations are depicted as given below:
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Fig-4.1 (a): Output Model- Particulate Matter (PM)
Fig-4.2 (a): Output Model- Sulphur-di-Oxide (SO2)
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Fig-4.3 (a) Output Model- Nitrogen Oxides (NOx)
Fig-4.4 (a) Output Model- Carbon Monoxide (CO)
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TABLE-4.6 (a) Predicted 24 Hourly Short Term Incremental Concentrations
Pollutants Maximum Incremental Conc. (μg/ m3)
Distance (km)/ Direction
Particulate Matter (PM) 3.332 0.2 km N
Sulphur-di-Oxide (SO2) 5.554 0.2 km N
Nitrogen Oxides (NOx) 31.941 0.2 km N
Carbon Monoxide (CO) 11.422 0.2 km N
Comments on Predicted Concentrations
A perusal of Table-4.6 (a) reveals that the maximum incremental short term 24 hourly ground level concentrations for PM, SO2, NOx and CO likely to be encountered due to DG sets are 3.332 μg/m3, 5.554 μg/m3, 31.941 μg/m3 and 11.422 μg/m3 occurring at a distance of 0.2 km in North direction.
The predictions indicate that the PM, CO, SO2 and NOx concentrations are likely to be well within the prescribed limit for residential and rural zone. Based on the above it can be inferred that the ambient air quality in the study area is unlikely to be affected due to the proposed drilling.
Resultant Concentrations after Implementation of the Project
The maximum incremental GLCs due to the proposed project for PM, CO, SO2 and NOx are superimposed on the maximum baseline PM, CO, SO2 and NOx concentrations recorded during the study to arrive at the likely resultant concentrations after commissioning of the proposed drilling. The cumulative concentrations (baseline + incremental) after implementation of the project are tabulated below in Table-4.7.
TABLE-4.7 (a) Resultant Concentrations due to INCREMENTAL GLC's
Pollutant Maximum AAQ Concentration Recorded During the Study
(ug/m3)
Incremental Concentration due to drilling
(ug/m3)
Resultant Concentration
(ug/m3)
AAQ Standard(CPCB) (ug/m3)
Particulate Matter (PM) 80.4 3.332 83.732 100
Sulphur-di-Oxide (SO2) 14.1 5.554 19.654 80
Nitrogen Oxides (NOx)
31.6 31.941 63.541 80
Carbon Monoxide (CO)
400 11.422 411.422 2000
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The maximum GLCs for PM, CO, SO2 and NOx after implementation of the proposed project are likely to be within the prescribed standards for Industrial, Rural, Residential and Other Areas. Further considering that the (maximum or minimum) GLCs occur at about 0.2 km, which is in the vicinity of the site boundary, therefore no impact on outside environment is envisaged. Based on the above details, it can be inferred that the ambient air quality in the study area is unlikely to be affected due to the proposed activity. The above air quality data reveals that even after considering incremental concentration in to baseline air quality from various operations, Ground Level Concentration (GLC) does not exceeds limits as prescribed by CPCB’s National Ambient Air Quality Standards (NAAQS). It may be concluded that impact of proposed activities will be of insignificant.
(b) Ahmedabad Meteorological Station
The Maximum GLC’s results for PM, CO, SO2 and NOx are presented in Table-4.6 (a) the isopleths for
PM, CO, SO2 and NOx concentrations are depicted as given below:
Fig-4.1 (b): Output Model- Particulate Matter (PM)
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Fig-4.2 (b): Output Model- Sulphur-di-Oxide (SO2)
Fig-4.3 (b) Output Model- Nitrogen Oxides (NOx)
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Fig-4.4 (b) Output Model- Carbon Monoxide (CO)
TABLE-4.6 (b) Predicted 24 Hourly Short Term Incremental Concentrations
Pollutants Maximum Incremental Conc. (μg/ m3)
Distance (km)/ Direction
Particulate Matter (PM) 1.738 0.15 km NE
Sulphur-di-Oxide (SO2) 2.896 0.15 km NE
Nitrogen Oxides (NOx) 16.656 0.15 km NE
Carbon Monoxide (CO) 9.155 0.10 km SE
Comments on Predicted Concentrations
A perusal of Table-4.6 (b) reveals that the maximum incremental short term 24 hourly ground level concentrations for PM, SO2, NOx and CO likely to be encountered due to DG sets are 1.738 μg/m3, 2.896 μg/m3, 16.656 μg/m3 and 9.155 μg/m3 occurring at a distance of 0.15 km in North-East direction for PM, SO2, NOx and at a distance of 0.15 km in South- East direction for CO.
The predictions indicate that the PM, CO, SO2 and NOx concentrations are likely to be well within the prescribed limit for residential and rural zone. Based on the above it can be inferred that the ambient air quality in the study area is unlikely to be affected due to the proposed drilling.
Resultant Concentrations after Implementation of the Project
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The maximum incremental GLCs due to the proposed project for PM, CO, SO2 and NOx are superimposed on the maximum baseline PM, CO, SO2 and NOx concentrations recorded during the study to arrive at the likely resultant concentrations after commissioning of the proposed drilling. The cumulative concentrations (baseline + incremental) after implementation of the project are tabulated below in Table-4.7(b).
TABLE-4.7 (b) Resultant Concentrations due to INCREMENTAL GLC's
Pollutant Maximum AAQ Concentration Recorded During the Study
(ug/m3)
Incremental Concentration due to drilling
(ug/m3)
Resultant Concentration
(ug/m3)
AAQ Standard(CPCB) (ug/m3)
Particulate Matter (PM) 80.4 1.738 82.138 100
Sulphur-di-Oxide (SO2) 14.1 2.896 16.996 80
Nitrogen Oxides (NOx)
31.6 16.656 48.256 80
Carbon Monoxide (CO)
400 9.155 409.155 2000
The maximum GLCs for PM, CO, SO2 and NOx after implementation of the proposed project are likely to be within the prescribed standards for Industrial, Rural, Residential and Other Areas. Further considering that the (maximum or minimum) GLCs occur at about 0.15-0.10 km, which is in the vicinity of the site boundary, therefore no impact on outside environment is envisaged. Based on the above details, it can be inferred that the ambient air quality in the study area is unlikely to be affected due to the proposed activity. The above air quality data reveals that even after considering incremental concentration in to baseline air quality from various operations, Ground Level Concentration (GLC) does not exceeds limits as prescribed by CPCB’s National Ambient Air Quality Standards (NAAQS). It may be concluded that impact of proposed activities will be of insignificant.
4.2.1.6 Mitigation Measures
Measures proposed to mitigate the effects of air emissions are as follows:
The exhaust of the DG sets will be at sufficient height to allow dispersions of the pollutants and periodical maintenance of DG sets so that emissions will be under limits.
Low sulphur diesel (Sulphur: 120 ppm) to reduce emissions of pollutant SO2.
Most of the equipment, machinery and vehicles have inbuilt pollution control devices.
The storage and handling of top soils and materials will be carefully managed to minimize the windblown material and dust.
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4.2.2 Noise Environment
The proposed drilling operations and related activities will lead to considerable emission of noise that may have significant impact on the surrounding communities in terms of increase in noise levels and associated disturbances. The potential impacts on noise level may arise out of the following.
4.2.2.1 Noise from the drilling rig:
Driller rotors and the power generators and pumps would be the main sources of noise pollution during the drilling activity. Noise due to vehicular movement will be intermittent, but will also add to the background noise levels. The well site during excavation phase of the site preparation where heavy earth moving machinery will be in operation, noise level of the vehicle should not be more than the 90 dB (A). Typically, the noise generating sources for the onshore drilling activity are provided below (in the immediate vicinity)
Diesel Generator : 90 to 95 dB(A)
Pumps at the Rig : 85 to 90 dB(A)
Miscellaneous : 80 to 85 dB(A)
Control Room & Quarters : 50 to 60 dB(A)
In order to predict ambient noise levels due to the proposed drilling the preparative modelling has been done. For computing the noise levels at various distances with respect to the plant site, noise levels are predicted using an user friendly model the details of which is elaborated below.
4.2.2.2. Mathematical Model for Sound Wave Propagation during Operation
For an approximate estimation of dispersion of noise in the ambient from the source point, a standard mathematical model for sound wave propagation is used. The sound pressure level generated by noise sources decreases with increasing distance from the source due to wave divergence. An additional decrease in sound pressure level with distance from the source is expected due to atmospheric effect or its interaction with objects in the transmission path.
For hemispherical sound wave propagation through homogenous loss free medium, one can estimate noise levels at various locations, due to different sources using model based on first principles, as per the following equation:
Lp2=Lp1-20 log(r2/r1) (1)
Where Lp2 and Lp1 are Sound Pressure Levels (SPLs) at points located at distances r2 and r1 from the source. The combined effect of all the sources then can be determined at various locations by the following equation.
Lp(total)=10 log (10(Lp1/10)+10(Lp2/10)+10 (Lp3/10) (2)
Where, Lp1, Lp2, Lp3 are noise pressure levels at a point due to different sources.
Based on the above equations a user friendly model has been developed. The details of the model are as follows:
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Maximum number of sources is limited to 200;
Noise levels can be predicted at any distance specified from the source;
Model is designed to take topography or flat terrain;
Coordinates of the sources in meters;
Maximum and Minimum levels are calculated by the model;
Output of the model in the form of isopleths; and
Environmental attenuation factors and machine corrections have not been incorporated in the model but corrections are made for the measured Leq levels.
4.2.2.3 Input for the Model
The incremental increase in noise levels due to the operation phase of the drilling has been done. Noise levels are mainly generated from DG sets, air compressors, pumps and transformers. The noise sources have been defined with respect to centre of drill site. The input data pertaining to corresponding noise level are tabulated below in Table-4.8.
TABLE-4.8 Input Data for Noise Modelling
Sr. No. Location Noise Levels dB(A)
1. Diesel Generator sets 90 to 95
2. Pumps and the rig 85 to 90
3. Miscellaneous 80 to 85
4. Control Room and Quarters 50 to 60
4.2.2.4 Presentation of Results
The predicted noise level at 100 m distance from the boundary of well site is 52.0 dB (A) and are tabulated in Table-4.9.
Table 4.9 Predicted Noise Levels
Sr. No. Distance from well site boundary Noise Levels dB(A)
1. 25 m 58.0
2. 50 m 55.0
3. 75 m 54.0
4. 100 m 52.0
On the basis of expected noise levels calculated through standard attenuation model, it is observed that the noise levels in the region would be within the standard limits (IS: 4954). The increase will only be marginal in comparison to the existing noise levels. The impact of the noise on general population is therefore expected to be insignificant.
4.2.2.5 Occupational Health Hazards from Noise Pollution
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Exposure to noise levels, above Threshold Limit Value (TLV), has been reported to have detrimental effect on the workers' health. Personnel’s working for more than 4 to 4.5 hours per shift near the sound pressure level of 90 dB(A) will be greatly affected, unless suitable mitigatory measures are taken. The adverse effects of high noise levels on exposed workers may result in:
Annoyance;
Fatigue;
Temporary shift of threshold limit of hearing;
Permanent loss of hearing; and
Hypertension and high blood cholesterol, etc. Noise pollution poses a major health risk to the workers near high noise source. If the magnitude of noise exceeds the tolerance limits, it is manifested in the form of discomfort leading to annoyance and in extreme cases to loss of hearing. Detrimental effects of noise pollution are not only related to sound pressure level and frequency, but also on the total duration of exposure and the age of the person. Table-4.10 below gives noise levels and associated mental and physical response of humans. During drilling operation, the personnel required to continually present in high noise source like DG is remote. All personnel working on rig are given noise abatement personnel protective equipment’s like earmuffs etc. Table 4.10 Noise Exposure Levels & its Effects
Noise Levels dB(A) Exposure Time Effects
85 Continuous Safe
85-90 Continuous Annoyance and irritation
90-100 Short term Temporary shift in hearing threshold, generally with
complete recovery
Above 100 Continuous Permanent loss of hearing
Short term Permanent hearing loss can be avoided
100-110 Several years Permanent deafness
110-120 Few months Permanent deafness
120 Short term Extreme discomfort
140 Short term Discomfort with actual pain
150 and above Single Exposure Mechanical damage to the ear
Source: OSHA
4.2.2.6 Community Noise Level The maximum predicted noise level at about 100 m from the boundary of the drill site is about 52.0 dB (A). The ambient noise levels at most of the places in the region are within the CPCB standards. Since,
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the drilling operations last for only 2-3/4-5 months at each location, impact of the noise pollution due to the proposed drilling will be insignificant on the community. It can be concluded that the impact due to elevated noise is confined only up to a distance of 100 m from the drilling point and in areas beyond this distance, the ambient noise levels are within the stipulated ambient noise quality norms.
4.2.2.7 Noise emanated by Machineries and equipment
In addition to the drilling activity, site preparation/closure related activities will also involve the operation of heavy equipment like pile drivers, loaders, tippers and bulldozers etc. Such heavy equipment are noted to emit considerable noise emissions which will get dispersed in the nearby communities thus resulting in a decrease in noise quality in the immediately adjacent settlement area. Most equipment and machinery will have noise control devices to reduce the emission levels.
4.2.2.8 Noise from vehicular traffic
Vehicles used for procuring goods, and manpower to the drill site and the subsequent transportation of rig/equipment and debris during decommissioning will use the site approach road and village roads. This will result in increase in traffic density to the site access road which will cause increase in noise levels in the nearby settlement and other sensitive receptors like schools, hospitals etc. located near the drill site. This may cause considerable noise disturbances to few residents living in the nearby areas as they were not very used to with such noise exposure. However this is a temporary in nature hence the impact may be considered insignificant.
4.2.2.9 Noise Control Measures
Typical mitigation measures for noise will include the following:
Sufficient engineering control during installation of equipment and machineries is ensured
Acoustic enclosures for the DG sets
All noise generating operations except drilling is restricted to daytime to the extent possible
Personnel Protective Equipment like ear plugs/muffs will be provided to the workers at the site
Undertake preventive maintenance of vehicles and machinery to reduce noise levels.
4.2.3 Water Environment
4.2.3.1 Sources of water Pollution
In general circumstances, the surface water impacts that could be potentially caused from the drilling activities are as follows:
Accumulation of the wastewater in the drilling site;
Potential wastewater discharges may arise from the following sources:
Treated domestic effluent (sewage and kitchen waste);
Spent drilling muds, cuttings and completion fluids disposal;
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(Potentially) contaminated storm water drainage from the derrick floor and other systems;
Seepage of drilling mud fluid into subsoil from mud collection & recirculation pond;
(Potentially) high sediment loads in runoff from unpaved well site areas during heavy shower; and
Any produced water and liquid hydrocarbon fractions collected in the test separator during well testing.
Potential accidental spills of fuel, lubricants or chemicals and leaks from engines (i.e. power generators, vehicles) and liquid hydrocarbons during testing; and
Waste handling particularly spent lubricants and chemicals during disposal may give rise to accidental releases.
4.2.3.2 Potential Surface and Groundwater Impacts
Drilling fluid or mud is basically a mixture of water, clay, polymers and weighting material with all individual components being environmentally friendly. The mud circulation is a closed loop with the return mud going back to the mud tanks. At the end of drilling operations, the residual (unusable) water based mud is discharged in to the waste pit. Since, lined pits will be used for solar evaporation of the unusable mud, the chances of run off or leaching is very low. Therefore, no significant impacts on water quality is envisaged due to the proposed drilling activity.
Location of well sites near to the rivers and major water bodies is however ruled out and thus any direct impact on water bodies is not anticipated. Therefore considering the water availability and abundant sources, there would be insignificant impacts on water resources due to usage in the project.
Based on the analyzed parameters, it can be concluded that surface water is not fit for drinking purposes unless it is treated and disinfected.Ground water in the region is potable in nature.
Based on the above-mentioned activities, the following potential impacts have been identified:
Potential for water logging during monsoon in the site;
Potential for adverse impact on the surface water quality;
Potential for adverse impact on the groundwater quality;
4.2.3.3 Impact on Surface Water Quality
The probability of contamination of surface water bodies and sub-surface water bodies was discussed above. The impact to the surface water bodies could arise from discharge from the site, disposal practice of spent drilling mud, cuttings, completion fluids, handling of liquid hydrocarbons, fuels etc. With the proposed concrete pavement and secondary containment provisions, the surface water quality contamination will be negligible. Noticeable impacts to water quality in nearby watercourses if any are more likely to occur as a result of increased suspended particle load. During the well site preparation the extent of impact to nearby watercourses will be function of:
Area cleared;
Amount of rainfall from the period between site construction and drilling;
Distance of the watercourse from the well site; and
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Mitigation measures to prevent any soil erosion within well site.
However, if the site preparation activities were conducted in dry season, the above impact would be
negligible or insignificant. Overall, with the appropriate measures to protect the well site and prevent
discharges, installation of soil erosion control measures, prevention of spillages while handling and
management of chemicals, the likely chances of impact on surface water will be minor.
4.2.3.4. Impact on Groundwater Regime
The water used for preparing drilling mud and for domestic needs of the campsite. The water requirement is primarily depended upon the depth of the proposed well and time required for the drilling the well. The drilling fluid will be recycled and fresh water will be used as makeup water and for general washing and daily maintenance. The water requirement is proposed to be met from the ONGC’s sources through tankers. Since the drilling activity being temporary and water requirement is meagre, no adverse impact on ground water resources is envisaged.
ONGC proposes to use water based non-toxic biodegradable fluids with inhibitive and encapsulative characteristics as drilling mud. Additionally, the drilling mud collection and recirculation pond is lined with impervious layer to prevent seepage and loss of drilling fluid into the subsoil. Further, proper casing installation and cementing will ensure least groundwater contact.
Apart from the mud characteristics, the waste and spent mud would be disposed in polyethylene propylene lined pits for all the storage areas as per the EHS Management Plan – Civil works. The mud components during the storage form a Bentonite (clay) lining along the pit wall preventing the seepage of water to the underground strata. Any hydrocarbons contamination will be skimmed off from site before proceeding to the next site so as to ensure that no leaching or subsurface contamination finally reaches the groundwater table. The waste oils and the skimmed oils collected from the drill site will be sent to the authorized recyclers.
Overall, with the appropriate management practices in place impacts on groundwater quality at the site is likely to be insignificant. The summary of impacts on water resources is given in Table-4.11
TABLE-4.11 SUMMARY OF IMPACT ASSESSMENT: WATER RESOURCES
Impact Area Nature of Impact1 Targets/Interests affected2
Magnitude and extent3 Overall significance
Surface Water
Physical Impact
Long term modification to the distribution of rain water catchment, if located near it
Local inhabitants depending on the water harvesting for water
Local, could be mitigated by avoiding water harvesting areas
Minor
Short term due to increase in siltation load of the water bodies in rainy season
Localized impact to surrounding Rivers and adjoining the water bodies in monsoon
Regional, and for short term Moderate
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Chemical Impact
Short term contamination of surface water flows due to untreated effluent, run-off, seepage from water holding tanks etc.,
Localised impact to surrounding nallahs and the river bodies in monsoon
Local, small scale mitigated by well site design and operations
Minor
Long term contamination in the region due to surface runoffs from well sites during flash floods
Could also result in sub surface contamination around the region
Regional, dependent on occurrence of flood. Good engineering. practices will reduce risk of flooding and overflow
Moderate
Ground Water
Groundwater quantity
Long & medium term, reduction due to percolation of subsurface contamination
Shallow aquifers surrounding the well sites
Local/Regional possibility remote with mitigation measures
Minor
Resource Management
Resource Management
Long term, medium reduction
Judicious abstraction of water for usage
Regional, Can be mitigated by sourcing water from water surplus catchment areas. Drill site borewell can be used by locals after drilling, if water quality is acceptable
Minor
1 Description; short or long term; reversible or permanent; associated with construction, operation, decommissioning; cumulative, accidental, etc. 2 Targets and interests potentially affected. 3 Adverse or beneficial; small, large, etc.; much localised (sites only), local, regional national. 4 Overall significance against criteria (minor; moderate, major)
4.2.4 Topography and Climate
4.2.4.1 Impact on Topography
The envisaged topographical changes would be due to the manmade structures like drilling rig and other associated structures. As mentioned previously drilling well is a short duration activity at each drilling location, typically encompassing a period of 6-7 months from land acquisition to site abandonment. The impact would therefore be localised, temporary and minimal.
4.2.4.2 Impact on Climate
Impact on the climatic conditions from the drilling will not be significant. The maximum temperatures of the exit gas from the DG stack and flare stack will be around 300°C and 400°C respectively. In terms of total emission of greenhouse gases and consequent impact on global warming or on potential for local increase of ambient temperature, considering the quantum of exit gas and the total duration of flow, the impact on the local or global climate will be insignificant.
4.2.5 Land Environment
Impact on land use and aesthetics is expected to be from vegetation clearance, excavation, leveling and grading of the site. Thus there might be need for clearing crops and trees. As the land requirement for each drill site is quite small (1.21-1.5 ha) compared to the large stretches of agricultural land there would
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be insignificant change to land use. Movement of heavy vehicles, earth moving equipment’s, and piling of removed soil at the site periphery during construction would have aesthetic impacts.
4.2.5.1 Land Required for Drilling Activity
Though drilling is a temporary activity yet the period for which the land is required would depend on discovery of hydrocarbons. Adequate compensation for loss of income from that piece of land, including crop loss, tree loss and any other direct or indirect loss as determined by the local revenue officials would be paid to the landowner.
4.2.5.2 Impact on Soil Quality
During drill site construction the major impacts on soil would occur due to excavation, compaction due to movement of heavy equipment and levelling. Site preparation will entail stripping and removal of the topsoil which contains most of the nutrients and organisms that give soil a living character and productivity. This will in turn result in minor changes in soil hydrology and small changes in the topsoil structure. However, as the project design takes into account the preservation of the top soil and it’s subsequently use for topping up of the rehabilitated land. The impact on soil quality will be insignificant considering the mitigation measures implemented.
4.2.5.3 Soil Contamination
The chances of soil contamination are from the storage and handling practices of chemicals and fuels, surface runoff carrying contaminated substances. The drilling mud could also add to the sub surface contamination if not handled appropriately.
4.2.5.4 Localized Alteration of Subsoil and Overland Drainage Patterns
The drilling activity is not likely to cause any noticeable impact in the drainage pattern of the area, since it is a temporary activity and confined to a small plot of land.
4.2.5.5 Alteration of Soil Quality by Loss of Topsoil
Loss of topsoil in these areas, either by mechanical removal or by erosion would alter the soil structure with resultant implications for re-vegetation. Measures inherent in the design of the project to minimize loss of topsoil and overburden are as follows:
Topsoil suitable for supporting agriculture, removed during site clearance will be retained, stored as a berm on the edge of the well site, protected from erosion by plastic sheeting;
Native vegetation, wherever appropriate will be kept at the edge of the well site as a seed bank, or replanted at an alternate location or will be used to protect/stabilize soil surfaces on slopes;
On demobilization, adequate measures would be provided to facilitate re-growth and hence
retention of top soils; and
Planned and systematic tree replanting program will be put in place.
On consideration of the poor vegetation cover, the physical features of the proposed block, the impact of drilling operations on soil quality will be insignificant. It is, however, important that mitigation measures
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are monitored to ensure that they are effective. Summary of impacts on soil and land use are given in Table-4.12
The mitigation measures inherent in the design of the well site, together with rigorous implementation of the waste management plan will ensure that significant impacts in relation to soil quality are not anticipated at the well site.
Table 4.12 Summary of Impact Assessment: Soil and Land Use
Impact Area Nature of Impact1
Targets/Interests2 Magnitude and extent3
Overall Magnitude4
Land Use Change in original land use, land degradation,
Original land use Well sites and access roads only, small scale; beneficial effect for afforestation and all weather access roads.
Minor
Derogation of Soil Quality
Cumulative contamination with dust, surface run-off; reversible
Soil quality, flora and fauna, including grazing livestock
Localised near sources; small contribution to existing background levels
Minor
Physical effects on soils due to topsoil removal, nutrient loss; reversible
Soil quality, flora Around the well location small scale degradation of soil quality
Minor
Soil Contamination
Subsurface contamination due to spillage and handling of the chemicals and other waste materials, reversible(partial)
Soil quality, groundwater flora and fauna and the grazing livestock
Localised near the source of operation and could be nullified with proper house-keeping & waste management
Minor
1 Description; short or long term; reversible or permanent; associated with construction, operation, decommissioning; cumulative, accidental, etc 2 Targets and interests potentially affected. 3 Adverse or beneficial; small, large, etc; very localised (sites only), local, regional national. 4 Overall significance against criteria (minor; moderate, major)
4.2.6 Biological Environment
Impact on the ecology of the study area will vary with the proximity of the habitats from the drilling locations. However, the impacts are of temporary nature, which will last only for few months at each drill
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location during the drilling activities and will thus allow subsequent recovery after the activities stops. Considering the above aspects the chance of irreversible ecological impact at the exploration stage is minor.
4.2.6.1 Impact on Terrestrial Environment
Prediction of Impacts on Biological Environment due to any drilling activity is practically difficult because:
Living objects has a natural variation in numbers, changes in numbers cannot always be directly attributed to changes in the environment
Most of the impacts on the living system or ecosystem takes long time period to become fully visible externally
As such, the forests are getting vanished and the growing industrialization will affect the plant life due to industrial pollution load and influx of population.
Therefore, to minimize the adverse effect of drilling activity, it is proposed to take adequate management measures as prescribed in the EMP.
The nearby natural vegetation will be disturbed for short duration till the drilling activity continues due to increase in pollution load. However, it will improve due to follow up of Environmental Management Plan (EMP).
Mangrove vegetation does not exist in the area hence no changes are anticipated.
There are no rare and endangered plant and animal species in the study area and hence no changes are anticipated. As regards soil microbiology, no oil bearing waste will be discharged to the ground and adequate emergency control measures in place to take care of any accidental spills.
4.2.6.2 Impact on Aquatic Environment
Waste mud and effluents from drilling activity will be contained in HDPE lined waste pit within the drill site premises and there will be no discharge to any aquatic environment. No disturbance or damage will be expected to the aquatic environment.
The primary form of impact could be in form of habitat disturbances, which would normalize after completion of the drilling activity. During the site preparation activities vegetation clearance would be nominal or minor. Efforts will be made to avoid areas of comparatively dense vegetation cover, unless absolutely essential. Efforts will be made to avoid areas of comparatively dense vegetation cover, unless absolutely essential. The impact due to air pollution on flora & fauna can be expected to be negligible, as the impact predictions based on the dispersion modelling do not indicate any significant release of the pollutants and ground level concentrations. Implementation of erosion and sediment controls to direct construction runoff through silt fences, sediment traps, and vegetative berms to decrease sedimentation in streams.
The flora and faunal habitats in the study area may be affected by erosion, siltation and water stagnation arising from run-on and runoff at the well site, if suitable mitigation measures are not implemented. The mitigation measures pertain to surface run-off from well site, wastewater discharges, solid waste disposal, erosion abatement measures, etc; As long as strict environmental management measures are put in place, including adequate measures for supervision of contractors and staff, negative effects on fauna will be minimized. There are however, likely to be some residual, unavoidable, impacts, linked to the
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requirement of optimal clearing the vegetation to facilitate drilling activities. Based on air dispersion modelling studies the resultant concentrations of ambient air pollutants were found to be well within the prescribed standards. Hence the impact on the ecology will be negligible. The summary of impact assessment on flora and fauna are given in Table-4.13.
TABLE-4.13 Summary of Impact Assessment Flora and Fauna
Aspect Nature1 Targets/Interests 2 Magnitude3 and extent
Overall Significance4
Loss of habitat
Loss of vegetation land
Flora and fauna, flora typically type vegetation, faunal comprise grazing animals and dependent mammals and reptiles.
Small & localised. . Beneficial, Medium,
Minor
Disturbance
Light, noise Surface run-off. Project duration only
Local community, Breeding birds, and flora and other fauna.
Small, localized. Mitigative measures in-built in equipment /well site design to meet ambient limits.
Moderate
Invading species
Colonisation by species associated with human activity
Avifauna and fauna and Weeds species
Small, Localised. No migration route / paths reported in the block.
Minor
Waste disposal/ run-off
Contaminated water/rain water,
Fauna, especially birds and reptiles
Small, Localised. No off-site disposal is likely to occur from the drilling operation. Area fenced and maintained even after drilling operation completed
Minor
1 Description; short or long term; reversible or permanent; associated with construction, operation, decommissioning; cumulative, accidental, etc 2 Targets and interests potentially affected. 3 Adverse or beneficial; small, large, etc; much localised (sites only), local, regional national. 4 Overall significance against criteria (minor; moderate, major)
4.2.7 Socio-Economic Environment
Although the well site would be selected to avoid any major social impacts, there will, nevertheless, be some issues that need to be addressed in the region. The drilling programme would involve setting up the actual drilling rig, construction of campsite for accommodation and operational crew. An approach road from the road head to the drilling rig will also be developed and also to facilitate regular transport from campsite.
It is anticipated that the drilling activity would involve direct and indirect impacts on socio-economic environment. These impacts are short term in nature.
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ONGC proposes to avoid any settlements, there is expected to be no displacement of people for the proposed drilling campaign. The well sites are expected to be in non-residential lands/ human settlement zones. The types of impacts due to drilling activities have been summarized below:
Land required for drilling activity
Partial loss of productivity of land due to the project
Temporary losses during the drilling activity
Common Property Resources
4.2.7.1 Impact on Civic Amenities
The area has limited network of roads and communication in the village areas. Many villages have been electrified during the last decade. There are few business centres and industrialized zones in the project block area. Although, the level of existing communications and support services in the area are considered adequate based on the population density, establishment of the proposed project would be a distinct beneficial impact. The overall impact is considered to be positive.
4.2.7.2 Impact on Health
Impact on health due to emissions and noise from drilling activity has been assessed to be minimal. In addition employees working at the drill site would be provided protective devices like ear plugs/ear muffs for ensuring minimum impact on human health.
4.2.7.3 Impact on social well being
At the drill sites, while communication between locals and outside workers may sometimes be good (exchange of information about places and lifestyle) there is a risk that an influx of migrant population from outside areas could well lead to social tensions. As a general rules, drill site would be located away from centres of population in order to minimize these risks.
Exploration drilling programme is expected to generate local employment at a particular location in the order of 8-10 unskilled and semi- skilled people, for a period of approximately 4-5 months at each drilling site location. While this benefit is small by most standards, it is a significant employment opportunity in that region.
4.2.7.4 Impact due to Vehicular Movement
The anticipated traffic volume during the construction phase of about 30 days, would approximately be 30 truckloads per day of material movement. The installation of the drill site equipment / facilities involves about 80 trailer loads spread over 10 days and during regular drilling operations on an average 5 truck movements per day with 10 small vehicles for the visitors and the drilling team would take place.
Considering the sparse vehicular movement in the block as a whole, the above anticipated traffic volume and the resulting emissions will be well within the stipulated ambient air quality norms.
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4.2.7.5 Other Impacts on Resources and Infrastructure
As highlighted earlier, infrastructure is very scarce in the study area, especially in the vicinity of the proposed well sites. Preparation and drilling operations could conceivably affect the following infrastructure.
Critically analysing the existing status of socio-economic profile vis-à-vis its scenario with proposed project, the impacts of the project would be of varying nature. The predicted impacts are as follows:
The proposed activities would generate indirect employment in the region; labour force will be required in site preparation and drilling activities, supply of raw material, auxiliary and ancillary works which will improve the economic status of the local unemployed persons.
The commissioning of project would lead to improvement in transport facilities as loose or soft surface rural roads and trails will be upgraded to facilitate movement of the drilling rig and supply vehicles
In the event of commercial quantities of hydrocarbons are discovered, more long term employment opportunities would be created and enhance the availability of fuel to various industries in this region.
Exploratory drilling is a temporary activity which lasts for about 4-5 months at each location. Thus, the environmental impacts are transient in nature and there will not be any residual impact on the environment.
4.2.8 Environment Management Plan
The objective of the Environmental Management Plan (EMP) is to identify project specific actions that will be undertaken to mitigate and manage impacts associated with the proposed drilling programme. In view of the proposed drilling project, the adequacy of the proposed pollution control measures has been analysed to meet the standards and norms of concerned authorities. The EMP reflects statutory requirements, ONGC’s own corporate operational guidelines for onshore hydrocarbon exploration and development projects. Cognizance has been taken of all the applicable standards and guidelines (amongst others) in the preparation of the EMP.
4.2.8.1 Atmospheric Emissions
Other potential sources of emissions which can cause impacts on environmental components are gaseous emissions and noise pressure levels at the rig. The gaseous emissions would routinely be contributed by D.G. sets deployed for power generation. There will be no sensitive receptors to the emissions of combustion products in the vicinity of the proposed drilling operations apart from the crew of the drilling rig. The impacts caused are therefore, considered to be negligible. Measures to ensure minimal impacts include:
Appropriate management of DG sets to achieve fuel efficiency and therefore reduce emissions;
Use of low sulphur diesel oil (<0.05% sulphur content) if available;
Environmental monitoring during drilling and well testing to ensure compliance to the standards;
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4.2.8.2 Noise Environment
The modelling results show that the noise levels will attenuate to below permissible levels within the drilling site boundary. However, the following measures that already exist on the drilling rig will be followed.
Generators will be properly enclosed;
The exhausts will be provided with silencers; and
Operators/personnel working near the noise sources at the DG sets of drilling rig will be provided with earmuffs and earplugs.
4.2.8.3 Soil Erosion
The following mitigation measures shall be taken to reduce the impact of soil erosion:
Minimize area extent of site clearance, by staying within the defined boundaries;
Stockpile of topsoil wherever possible and applicable at the edge of site;
Install and maintain effective run-off controls, including siltation ponds, traps and diffusion methods so as to minimize erosion; and
Avoid uprooting trees or removing undergrowth where possible so as to retain land stability;
4.2.8.4 Land Environment
Drilling fluid or mud is basically a mixture of water, clay, polymers and weighting material with all individual components being environmentally friendly. This mud will be reused as much as possible. The mud circulation is a closed loop with the return mud going back to the mud tanks. At the end of drilling operations, the residual (unusable) mud is discharged in to the waste pit after proper DWM conditioning.
4.2.8.5. Water Environment
No significant impacts on water quality are envisaged due to the drilling activity as there is no discharge of waste water to the outside water bodies. All the waste water is contained in the lined waste pit and used for recycling. Garland drain is provided at the site to contain excess water during rains.
4.2.8.6 Biological Environment
The impacts on ecology of this area will be insignificant because of short term nature of the activity. There will be no disturbance on surrounding ecology except marginal increase in the pollution levels due to air emissions. However, these effects will be negligible and short term, hence diluted fast and regained to the normal levels.
4.2.8.7 Socio-economic Environment
The impact on community health due to the proposed drilling activities is negligible but the social status will improve due to increase in employment opportunities. There will be positive impact on sanitation, transportation, communication and community health in the region. There will be some occupational
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hazards due to proposed activities but these hazards will reduce through implementation of precautionary measures suggested in EMP.
Need base assessment of the villages
The objective of the need base assessment was to know views on the project activities and expectation of the community residing in the study area from the project authority. A structured questionnaire was used for the community consultation survey in the study area. Data collected for education, drinking water, health, communication, power, market facilities etc.
In addition, consultations were held with the Sarpanch, school teachers and village elders to get an idea about the social structure of the village, immediate infrastructural needs of the village and type of support required from the project proponent to improve the living standards of the village community and cope with the changes that are associated with industrialization.
Collected data interpreted and analyzed to know the needs of the villagers. Main issues of the study area were found drinking water problem in summer season, sanitation, no proper medical facility in villages, lack of employment opportunities etc.
Based on the survey findings, it was observed that sanitation, drainage, health facilities, were lacking in villages. Development in those field is needed for the villages. The Prediction of Qualitative Impacts on Socio-economic Environment is described in Table-4.14.
Table 4.14 Prediction of Qualitative Impacts in Socio Economic Environment
Parameter Local Regional Direct Indirect Reversible Irreversible
Employment
Income
Transport
Education
Medical Facilities
Communication
Sanitation
Housing
Health
Recreation
Agriculture
Cost Of Living
Business
Per Capita Income
Pollution
Positive Impact, Negative Impact and Insignificant
Positive Impacts of the Proposed Project
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The Positive impacts identified from proposed project are described below:
Increase in employment opportunities during the drilling may have distinctive impact on the socio-economic development of the region
Fulfilment of the energy demand in the industrial sector of the region which will ultimately improve the economy of the region
Quality of life will improve by proposed project through development of infrastructure resources such as roads, water supply, electricity etc.
Many auxiliary and ancillary industries may develop due to the proposed project activity
Negative Impacts of the Proposed Project
drilling of oil & gas wells activities have the potential to affect the native communities temporarily.
During rig movement and rig building period there will be short-term socioeconomic impacts in the study area that may include increase in floating population (contractual) and there will be marginal strain on the civic amenities like drinking water, sanitation, road transport and other facilities.
Occupational hazards in terms of injuries & accidents may occur during movement of rig & drilling of the wells
Vehicle and drilling equipment can create noise pollution.
Temporary impact on quality of air and land.
Mitigation Measures of the Proposed Project
All equipment is operated within specified design parameters during drilling.
Impact on air quality will be minimized by reducing the duration of testing through careful planning and using high combustion efficiency, smokeless flare/ burners
Acoustic enclosures and mufflers will be provided to DG sets to reduce noise levels. Ear muffs/plugs and other protective devices will be provided to the workforce in noise prone areas.
Wherever generator noise occurs in proximity to human settlements, sound deadening barriers will be provided.
The effluents (wastewater) and cuttings generated during drilling operations are collected only in lined waste pits and no waste water is discharged outside.
4.2.9 Environmental measures during well construction
i. As a preventive measure to avoid impacts the well site will be located based on the following consideration:
Located at least 300 - 500 m away from the nearest village habitat / sensitive receptors;
Located at least the height of the well must away from public road;
Located at least 300 - 500 m away from existing water bodies;
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Ensure natural drainage channels are avoided or drainage channels rerouted to ensure unhindered flow of rain / flood water. Where necessary adequate erosion control measures will be provided;
Located in a manner to avoid plantations of timber yielding trees
ii. Construction activities will be coordinated in consultation with landowners and local authorities to reduce interference with agricultural activities
iii. In dry weather conditions, water sprinkling during excavation, levelling and transportation will be implemented.
iv. Topsoil will be stripped below plough depth from the well site and stored on the site. The depth of stripping will be on the basis of site specific soil survey. Topsoil will also be stripped from and stored adjacent to the site.
v. The well site ground level will be raised and hard standing provided. Drainage channels around the site area will be constructed to ensure no obstruction to flow pattern.
vi. The approach roads will be routed in a manner so that disturbance to existing activity and to the local community is minimized. Routing through village habitat areas will be avoided, as far as practical. The road surface will be maintained to minimize generation of vehicular movement dust in the local area.
vii. The drill site would be provided with sufficient and suitable sanitary facilities and these will be connected to well designed and maintained septic tanks.
viii. The chemical and diesel storage area will be paved and provided with spill containment walls. Pits for storage of water, drilling mud and drill cuttings will be provided with impervious liner. Sufficient free-board will be provided to prevent overflow.
ix. It would be ensured that diesel powered construction vehicles are properly maintained. Vehicle maintenance would be carried out authorised service centres. Service centres will be so selected to ensure that these conform to statutory regulations.
Removal of Equipment and Materials
In the event that economic quantities of hydrocarbons are found, the well will be suspended with a wellhead in place, but all other equipment and materials will be removed from the site. All empty drums, wastes, used and unused drilling fluids, fuel and lubricants will be removed from the drilling site. Water supply and effluent discharge hoses and associated equipment will be removed. The access road(s) would be reinstated.
4.2.9.1 Management of Drilling Wastes
The major waste product of a drilling operation is the generation of rock cuttings with residual mud adhering to the drill cuttings and spent drilling fluid. About 500 m3 drill cuttings per well and 5 m3/day spent drilling fluid would need to be disposed of. Following measures to be adopted for disposal of drill cutting and residual drilling fluids: