Draft Environment Impact Assessment Report For Onshore Oil ...
Transcript of Draft Environment Impact Assessment Report For Onshore Oil ...
Draft Environment Impact Assessment Report
For
Onshore Oil & Gas Exploration of 46 wells in 12 ML
Blocks of Western Onshore Basin, District Mehsana,
Gujarat
Submitted By
Oil and Natural Gas Corporation Limited
Corporate Health, Safety and Environment,
3rd Floor, Tower A, Deendayal Urja Bhawan,
Plot No.5, Vasant Kunj, Nelson Mandela Marg,
New Delhi-110070
Draft Environmental Impact Assessment Report
for
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of
Western Onshore Basin, District Mehsana, Gujarat
Submitted By
Oil and Natural Gas Corporation Limited
Corporate Health, Safety and Environment,
3rd Floor, Tower A, Deendayal Urja Bhawan,
Plot No.5, Vasant Kunj, Nelson Mandela Marg,
New Delhi-110070
(I) Declaration by Experts contributing to the EIA
I, hereby, certify that I was a part of the EIA team in the following capacity that developed
the above EIA.
EIA coordinator: Name: Harendra Singh
Signature and Date:
Period of involvement: July 2018 till date
Functional area experts:
S. no. Functional
Area
Name of the
Experts
Involvement
(Period and task)
Signature
1. 1
.
AP* Vartika Roy AAQ monitoring plan,
impact prediction &
management plan studies
(July’2018 till date)
2. 2 WP* B.P.Babu/Ashish
Bhuwan
Water Pollution monitoring,
Prevention and Control
studies (July’2018 till date)
3. 4 SE* S.K.Mohapatra Socioeconomic study
(July’2018 till date)
4. 5 EB* Dr. Archana Yadav Ecology & Biodiversity
studies (July’2018 till date)
5. 6 HG* Debashis
Chakraborty
Hydrology Studies
(July’2018 till date)
6. 7 GEO* Debashis
Chakraborty
Geology studies (July’2018
till date)
7. 8 SC* R R Dwivedi Soil Quality, impacts and
conservation measures
(July’2018 till date)
8. 9 AQ* Setu Goyal Air quality assessment
studies (July’2018 till date)
9. 1
0
NV* D.K.Trivedi Noise/Vibration Studies
(July’2018 till date)
10. 1
1
LU* Nilay Meshram Land Use Studies
(July’2018 till date)
11. 1
2
RH* Amlan Chakraborty Risk Assessment and
DMP studies (July’2018 till
date)
Team Members:, Mrs. Alaknanda Dubey and Mr. Vipul Sharma
(II) Declaration by the Head of the accredited consultant organization/
authorized person
I, Harendra Singh, hereby, confirm that the above mentioned experts prepared the EIA
“Onshore Oil & Gas Exploration of 46 wells in 12 ML blocks in Mehsana district,
Gujarat”. I also confirm that the consultant organization shall be fully accountable for
any mis-leading information mentioned in this statement.
Signature:
Name: Harendra Singh
Designation: General Manager
Name of the EIA consultant organization: Oil & Natural Gas Corporation Ltd.
NABET Certificate No. & Issue Date: NABET/EIA/1518/RA0054, 14/06/2017
(III) Document No. ONGC/CHSE/EIA/WOB/2018-19/01
(IV) Review and Revision History
History of revisions of the present report
Rev Date Modifications
Rev. 00 Draft 20/12/2018 Preliminary Draft EIA Report
Rev.01 Draft 31/12/2018 Draft EIA report for Reviewer Comments
Rev. 02 Draft 08/01/2019 Final Draft EIA report
Review DATE DESCRIPTION REVIEWER-1 REVIEWER-2
Review. 00
Draft
20/12/2018 Preliminary
Draft EIA
Report
Mr. Golap C
Boruah
Mr. Rajeeva Kumar
Review.01
Draft
31/12/2018 Draft EIA
report for
Reviewer
Comments
Mr. Rajeeva
Kumar
Dr. Naveen Raj
Review.02
Draft
07/01/2019 Final Draft EIA
Report
Mr. M.K.Garg Mr. Randhir
Chakravarti
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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TABLE OF CONTENTS
Abbreviations & Glossary i-ix
ToR Compliance x-xiv
Executive Summary xv-xxx
CHAPTER-1: INTRODUCTION
1.0 Introduction 2
1.1 Purpose of the Report 2
1.2 Identification of Project and Project Proponent 3
1.2.1. Identification of the Project 3
1.2.2. Project Proponent 3
1.2.3. Proposed Project 3
1.3 Brief Description of the Project 4
1.3.1. Nature of the Project 4
1.3.2. Size of the Project 4
1.3.3. Project Site Details 4
1.3.4 Importance of the Project 13
1.4 Scope of the Study 14
1.4.1 Administrative and Legislative Background 15
1.4.2 Study Area for EIA 15
1.4.3 Methodology of the Study 15
1.5 Contents of the Report 17
1.6 Status and Stage of Regulatory Framework 19
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CHAPTER-2: PROJECT DESCRIPTION
2.1 Introduction 21
2.2 Type of the Project 21
2.3 Need Of the Project 21
2.4 Project Location and Project Detail 22
2.4.1 Typical Well site details 22
2.5 Size or Magnitude of Operation 23
2.5.1 Resource Requirement for the Project 24
2.5.1.1 Land Requirement 24
2.5.1.2 Water Requirement 24
2.5.1.3 Power Requirement 26
2.5.1.4 Man Power Requirement 27
2.5.1.5 Drilling Mud 27
2.6 Proposed Schedule for the Project Approval and Implementation 28
2.7 Technology and Drilling Process Description 29
2.7.1 Drilling of Exploratory well 30
2.7.2 Proposed Hole Size / Casing Programme 32
2.7.3 Surface Testing & Flaring 32
2.8 Details of Project Utilities 33
2.8.1 Site Preparation 33
2.8.2 Approach Roads 33
2.8.2.1 Installation of Facilities 34
2.9 Post Drilling Operations - Abandonment and Restoration 40
2.9.1 Demobilization & Decommissioning 40
2.9.2 Restoration of Well Sites 40
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2.9.3 Traffic Volumes 41
2.10 Sources of Pollution 42
2.10.1 General 42
2.10.2 Wastewater Generation and Disposal 42
2.10.3 Air Emissions 43
2.10.4 Solid Waste 44
2.10.4.1 Drilling Mud 44
2.10.4.2 Drill Cuttings 44
2.10.4.3.Waste Pit Details 45
2.10.4.4 Used/Spent Oil 45
2.10.4.5 Drilling Mud & Drill Cuttings Analysis 45
2.10.5 Noise Levels 46
2.11 Qualifications, Skills and Training Practice 47
CHAPTER-3: DESCRIPTION OF THE ENVIRONMENT
3.1 Baseline Environmental Study 51
3.2 Geology 52
3.3 Hydrogeology 53
3.3.1 Ground Water Resources 54
3.4 Seismicity and Floods 56
3.5 Land Environment 58
3.5.1 Topography 58
3.5.2 Land Use Studies 58
3.5.2.1 Methodology 58
3.6 Meteorology 61
3.6.1 Meteorological data recorded at study area 61
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3.6.2 Secondary Data from Indian Meteorological Dept., (IMD), Ahmedabad 63
3.7 Ambient Air Quality 67
3.7.1 Selection of Sampling Locations 67
3.7.2 Frequency and Parameters for Sampling 67
3.7.3 Instruments used for Sampling 68
3.7.4 Sampling and Analytical Techniques 68
3.7.5 Ambient Air Quality Results 72
3.7.6 Summary of Ambient Air Quality Results 72
3.7.7 Observations 73
3.8 Noise Environment 76
3.8.1 Methodology for Noise Monitoring 76
3.8.2 Details of Noise Monitoring Locations & Presentations of Results 77
3.8.3 Observations 83
3.9 Water Environment 85
3.9.1 Reconnaissance of study area 85
3.9.2 Water Quality Monitoring 85
85 3.9.3 Sampling and Analysis Techniques 85
3.9.4 Details of water Sampling Locations 85
3.9.5 Presentation of Results 88
3.9.6 Observations 107
3.10 Soil Quality 110
3.10.1 Sampling and Analysis Techniques 110
3.10.2 Details of Soil Sampling Locations 110
3.10.3 Presentation of Results 111
3.10.4 Observations 114
3.11 Biological Environment 116
3.11.1 Introduction 116
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3.11.2 Reconnaissance of study area 116
3.11.3 Assessment of Flora 116
3.11.4 Vegetation of Study Area 121
3.11.5 Assessment of Fauna 122
3.11.6 Aquatic Ecology 128
3.11.6.1 Sampling Procedure 128
3.11.6.2 Method of Analysis 128
3.11.6.3 Species Diversity 129
3.11.7 Conclusion 133
3.12 Socio-economic Environment 134
3.12.1 Baseline Status 134
3.12.2 Methodology for Primary Data Collection 135
3.12.3 Demography 135
3.12.4 Literacy 137
3.12.5 Urban/Rural Population Mehsana district 138
3.12.6 Social Structure 138
3.12.7 Occupational Structure 139
3.12.8 Infrastructure Facilities 140
3.12.8.1 Educational Facilities 140
3.12.8.2 Health Facilities in Rural Area 141
3.12.9 Drinking Water facility in the rural villages of the study area 141
3.12.10 Public Consultation during Primary Survey 142
3.12.11 Salient Observations of the study 143
3.12.12 Economic Profile 145
3.12.13 Cultural & Aesthetic attributes 146
3.12.13.1 Festival celebrated in the study area 146
3.12.14 Community Consultation 146
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CHAPTER-4: ANTICIPATED ENVIRONMENTAL IMPACTS & MITIGATION MEASURES
4.1 Introduction 148
4.2 Impact Assessment and Mitigation Measures 149
4.2.1 Air Environment 151
4.2.1.1 Potential Impacts 151
4.2.1.2 Fugitive Emissions 151
4.2.1.3 Air Pollution Modelling 152
4.2.1.4 Model Input Data 152
4.2.1.5 Presentation of Results 153
4.2.1.6 Mitigation measures 157
4.2.2 Noise Environment 157
4.2.2.1 Noise from the drilling rig 157
4.2.2.2 Mathematical model for sound wave propagation during operation 158
4.2.2.3 Input for the Model 158
4.2.2.4 Presentation of Results 159
4.2.2.5 Occupational Health Hazards from noise pollution 159
4.2.2.6 Community Noise Level 160
4.2.2.7 Noise emanated by Machineries and Equipment 160
4.2.2.8 Noise from Vehicular Traffic 161
4.2.2.9 Noise Control Measures 161
4.2.3 Water Environment 161
4.2.3.1 Sources of water Pollution 161
4.2.3.2 Potential surface and ground water impacts 162
4.2.3.3 Impact to surface water quality 162
4.2.3.4 Impact on ground water regime 163
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4.2.4 Topography and Climate 164
4.2.4.1 Impact on Topography 164
4.2.4.2 Impact on Climate 164
4.2.5 Land Environment 164
4.2.5.1 Land required for drilling activity 165
4.2.5.2 Impact on soil quality 165
4.2.5.3 Soil Contamination 165
4.2.5.4 Localized Alteration of subsoil and overland drainage pattern 165
4.2.5.5 Alteration of soil quality by loss of topsoil 165
4.2.6 Biological Environment 166
4.2.6.1 Impact on Terrestrial Environment 167
4.2.6.2 Impact on Aquatic Environment 167
4.2.7 Socio-Economic Environment 168
4.2.7.1 Impact on civic amenities 169
4.2.7.2 Impact on health 169
4.2.7.3 Impact on social well being 169
4.2.7.4 Impact due to vehicular movement 169
4.2.7.5 Other impacts on resources and infrastructure 170
4.2.8 Environment Management Plan 170
4.2.8.1 Atmospheric Emissions 170
4.2.8.2 Noise Environment 171
4.2.8.3 Soil Erosion 171
4.2.8.4 Land Environment 171
4.2.8.5 Water Environment 171
4.2.8.6 Biological Environment 171
4.2.8.7 Socio-economic Environment 171
4.2.9 Environmental Measures during well construction 173
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4.2.9.1 Management of Drilling Wastes 174
4.2.9.2 Management of Solid Wastes 175
4.2.9.3 Management of Discharge of aqueous Effluents 176
4.2.9.4 Management of waste disposal sites within drill site 176
4.2.10 Drilling Program Safety Guidelines 177
4.2.11 Monitoring Environmental Performance 177
4.2.12 Drilling Site Restoration Plan 177
4.2.13 Decommissioning upon abandonment 178
4.2.14 Occupational Health Surveillance Program 178
CHAPTER-5 ANALYSIS OF ALTERNATIVES (TECHNOLOGY & SITE)
5.1 Alternatives for Project Site 184
5.2 Alternatives for Technology 184
CHAPTER-6 ENVIRONMENTAL MONITORING PROGRAM
6.1 Environmental Monitoring and Reporting Procedure 186
6.2 Reporting Schedules Of The Monitoring Data 196
6.3 Infrastructure for Monitoring of Environmental Protection Measures 196
6.3.1 Air Quality and Meteorology 196
6.3.2 Water and waste water quality 197
6.3. Noise levels 198
6.4 Audit and Review 198
CHAPTER-7: ADDITIONAL STUDIES
7.1 Risk Assessment 201
7.1.1 Approach to the Study 201
7.1.2 Maximum Credible Accident Analysis (MCAA) 201
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7.1.3 Damage Effects of Various Heat Loads 206
7.1.4 Scenario Identification 207
7.1.5 Input Data for Consequence Analysis 207
7.1.6 Results and Discussion 209
7.1.7 Failure Frequency Analysis 209
7.1.8 Historical Data Sources 209
7.1.9 Probability of Immediate Ignition and Individual Risk Assessment Criteria 210
7.1.10 Individual Risk Assessment 210
7.1.11 Geo Hazards 211
7.2 Recommendations to mitigate blow out Risk / Hazards 211
7.3 Disaster Management Plan 212
7.3.1 Objectives of Disaster Management Plan 212
7.3.2 Different Phases of Disaster 213
7.3.2.1 Warning Phase 213
7.3.2.2 Period of Impact Phase 214
7.3.2.3 Rescue Phase 214
7.3.2.4 Relief Phase 215
7.3.2.5 Rehabilitation Phase 215
7.3.3 Key Elements of DMP 215
7.3.3.1 Basis of the Plan 215
7.3.3.2 Onsite Disaster Management Plan Purpose 215
7.3.3.3 Offsite Disaster Management Plan Purpose 216
7.3.4 Level of Emergencies 217
7.3.4.1 Minor Emergency 218
7.3.4.2 Major Emergency 219
7.3.5 Overall Philosophy of Emergency Response 220
7.3.6 Auditing 220
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7.3.7 Emergency Priorities 220
7.3.8 Emergency Response Management Group Interfaces 221
7.3.9 Emergency Response Procedure 221
7.3.9.1 Minor Emergency 221
7.3.9.2 Major Emergency 221
7.3.9.3 Emergency Response Strategies 223
7.3.10 Alert Phase 224
7.3.11 Preparedness for Emergencies 224
7.3.12 Control of Emergencies 225
7.4 Emergency Response Action 225
7.5 Emergency Response Procedures 226
7.5.1 Blow Out 226
7.5.2 Well Control 229
7.5.3 Hydrogen Sulphide 230
7.5.4 Abandonment of Rig/well 231
7.5.5 Structural Damage/Failure of the Rig 232
7.5.6 Well Control Emergencies 233
7.5.7 Fire on Rig 234
7.5.8 Rig Evacuation 235
7.5.9 Gas Release on Rig 236
7.5.10 Structural Damage 237
7.5.11 Ground Movement 238
7.5.12 Un-Ignited Gas Release 239
7.5.13 Hydrocarbon Spill 240
7.5.14 Medical Evacuation 241
7.5.15 Criminal Acts 242
7.5.16 Bomb Threat/ Extortion 243
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7.6 End of Emergency 244
7.7 Communications 245
7.7.1 Communication Network 245
7.8 Occupational Health & Safety Management Plan 245
CHAPTER-8: PROJECT BENEFITS
8.0 Project Benefits 248
8.1 Improvements in the Physical Infrastructure 248
8.2 Improvements in the Social Infrastructure 248
8.3 Employment Potential Other Tangible Benefits 249
CHAPTER-9: ENVIRONMENTAL COST BENEFIT ANALYSIS
9.1 Project Cost 251
9.2 Capital and Recurring Cost 252
CHAPTER-10: ENVIRONMENT MANAGEMENT PLAN
10.1 Introduction 254
10.2 EMP during Various Project Phases 255
10.3 Environmental Policy of the Company 255
10.4 Organisation Structure-HSE 255
10.5 EMP Plan for the Proposed Project 255
10.6 Environment Protection and Reclamation Plan 256
10.7 Environment Management Plan 257
10.7.1 Air Environment 257
10.7.2 Noise Environment 258
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10.7.3 Water Environment 258
10.7.4 Biological Environment 259
10.7.5 Land Environment 259
10.7.6 Soil Environment 260
10.7.7 Storage and Handling of Materials and Spills 260
10.7.8 Social Management Plan 261
Annexures
Annexure – I TOR
Annexure – II Corporate Environmental Policy
Annexure – III Air Monitoring Results
Annexure – IV Applicable Environmental Standards
List of Tables
Table No. Title Page No.
1.1 Brief description of project 09
1.2 Block Coordinates of 21 ML Blocks 10
1.3 Environmental Attributes and frequency of monitoring 16
2.1 Salient Features of the Proposed Project 24
2.2 Water Requirements for each well site 25
2.3 Details of DG sets 27
2.4 Constituents of Water Based Mud (WBM) 27
2.5 Special Additives and their Functions in water based mud 28
3.1 Land use Pattern of Mehsana 60
3.2 Summary Of The Meteorological Data Generated In Study Area 61
3.3 Summary Of Wind Pattern at Rupal 62
3.4 Weather Data From IMD, Ahmedabad (1971-2000) 65
3.5 Techniques Used For Ambient Air Quality Monitoring 68
3.6 Details Of Ambient Air Quality Monitoring Locations 69
3.7 Summary of Ambient Air Quality Monitoring Results 72
3.8 Noise Level Monitoring of Locations 78
3.9 Ground Water Sampling Locations 86
3.10 Surface Water Sampling Locations 86
3.11(a) Ground water Analysis Results 89
3.11 (b) Ground water Analysis Results 92
3.12 (a) Surface Water Analysis Results 95
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3.12 (b) Surface Water Analysis Results 99
3.12 (c) Surface Water Analysis Results 102
3.13 Soil Analysis Locations 110
3.14 (a) Soil Analysis Results 111
3.14 (b) Soil Analysis Results 113
3.15 List of Flora recorded in Block Area 117
3.16 List of Fauna around the Project Area 124
3.17 List Of Phytoplankton Species Identified From Study Area 131
3.18 List Of Zooplankton Species Identified From Study Area 131
3.19 Details Of Aquatic Sampling Locations 131
4.1 Key Potential Impacts Of Exploration Activities 148
4.2 Impact Significance Criteria 149
4.3 Activities – Impacts/Risks Interaction Environmental Sensitivities 150
4.4 Details Of DG Sets 152
4.5 Emission Characteristics- Model Inputs 153
4.6 Predicted 24 Hourly Short Term Incremental Concentrations 156
4.7 Resultant Concentrations due to INCREMENTAL GLC's 156
4.8 Input Data for Noise Modelling 159
4.9 Predicted Noise Levels 159
4.10 Noise Exposure Levels & its Effects 160
4.11 Summary Of Impact Assessment: Water Resources 163
4.12 Summary of Impact Assessment: Soil and Land Use 166
4.13 Summary of Impact Assessment Flora and Fauna 168
4.14 Prediction of Qualitative Impacts in Socio Economic Environment 172
4.15 Summary of Identified Impacts and Proposed Mitigation Measures 178
6.1 Schedule Of Environmental Monitoring 188
7.1 List Of Major Hazards 203
7.2 Occupational Hazards 203
7.3 Damage Due To Peak Over Pressure 206
7.4 Damage Due To Incident Radiation Intensities 206
7.5 Input Data For Consequence Analysis 208
7.6 Summary Of Consequence Analysis For Jet Fire Scenario At Well 209
7.7 Probability Of Ignition For Leaks Of Flammable Fluids 210
7.8 The Adnoc Individual Risk Assessment Criteria 210
7.9 Recommendations To Mitigate Blow Out Risk/Hazards 211
7.10 Emergency Operation Taskforce Functions 216
9.1 Project Cost 251
9.2 Capital and Recurring Cost for Pollution Control Measures 252
10.1 Summary Of Environmental Management Actions 264
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List of Figures
Figure No.
Title Page No.
1.1 Index Map of the area 5
1.2 Topographic Map Of Block Locations In Sivsagar District 6
2.1 Water Balance of each well site 26
2.2 Drilling Rig Sketch 31
2.3 Drilling Fluid Circulation System At Typical Rig 39
2.4 Typical Section View Of Drilling Cut And Drill Mud Collection Pit 46
3.1 Hydrogeology Map of District 53
3.2 Ground Water Pre Monsoon Level map of Mehsana District 55
3.3 Ground Water Post Monsoon Level map of Mehsana District 56
3.4 Seismic Zone Map of India 57
3.5 Seismic Zone-III of Study Area 57
3.6 Land Use Pattern Of Study Area 59
3.7(a) Windrose Diagram For April-18, May -18, June 18 & July 18 At Rupal 62
3.7 (b) Windrose Diagram For April-18, May -18, June 18 & July 18 At Rupal 63
3.8(a) Windrose Diagrams For The Month Of April, May, June & July - IMD, Ahmedabad(1971- 2000)
64
3.8 (b) Windrose Diagrams For The Month Of April, May, June & July - IMD, Ahmedabad (1971- 2000)
65
3.9 Monthly average Maximum & Minimum Temperature in ºC 66
3.10 Monthly average rainfall in mm & Relative humidity in % 66
3.11 Map Showing AAQ Monitoring Stations 70
3.12 Photographs Of Ambient Air Quality Monitoring Locations 71
3.13 Variation of Particulate Matter PM10 in the study area 74
3.14 Variation of Particulate Matter PM2.5 in the study area 74
3.15 Variation of Sulphur di oxide (SO2) in the study area 75
3.16 Variation of Oxides of Nitrogen (NOx) in the study area 75
3.17 Map Showing Noise Monitoring Stations 77
3.18 Noise Quality Monitoring At Various Locations 83
3.19 Map Showing Ground And Surface Water Monitoring Stations 87
3.20 Photographs Of Ground Water Monitoring 108
3.21 Photographs Of Surface Water Monitoring 109
3.22 Maps showing Monitoring Locations 111
3.23 Particle Size Distribution 114
3.24 Soil Sampling Location 115
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3.25 Sampling of Study Area 119
3.26 Vegetation of Study Area 120
3.27 Mushrooms found in the study area 121
3.28 Birds found in the study area 123
3.29 Nilgai found in the Agricultural field of study area 126
3.30 Tortoises found in the pond of study area 127
3.31 Indian star tortoises found in the study area 127
3.32 Aquatic Sampling Location of the study area 129
3.33 Shannon Diversity Index of Planktons 133
3.34 Distribution of population in the study area 136
3.35 Population density 137
3.36 Literacy level of the population in the study area 137
3.37 Distribution of Population by Social structure 139 3.38 Occupational Structure of the population 139 3.39 Socioeconomic Survey of the study area 143 3.40 Animal Husbandry of study area 145 7.3 Flowchart For Evaluation Of Consequences During The Release Of
Flammable Or Toxic Chemical 208
7.4 DMP Process Flow Diagram 214 7.5 Organizational Setup For The On-Site DMP 218 7.6 Organizational Setup For The Off-Site DMP 219 7.7 Emergency Classification 222 7.8 Contingency Plan For Onshore Blowout (Drilling Rig) 228 7.9 Typical Schematic Of Bop Stack 231 10.1 Plants Which Counteract Air Pollution (Odour Of Sulphur) 263
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Chapter No. Abbreviations & Glossary
i
ABBREVIATIONS
BLEVE Boiling Liquid Evaporating Vapour Explosion
BOD Biological Oxygen Demand
BOP Blow-out Preventer
CAGR Compounded Annual Growth Rate
CC&A Common Consent and Authorization (Consent to Operate (for water and air emissions) and Authorization (for management of hazardous wastes)
CGWA Central Ground Water Authority
COD Chemical Oxygen Demand
CPCB Central Pollution Control Board
DG Diesel Generator
DGH Directorate General of Hydrocarbons
DMP Disaster Management Plan
EC Environmental Clearance
ECC Emergency Control Centre
EHS Environmental Health and Safety
EIA Environmental Impact Assessment
EMP Environmental Management Plan
EOR Enhanced oil Recovery
FAE Functional Area Expert
GGS Group Gathering Stations
GLC Ground Level Concentration
GoI Government of India
GPCB Gujarat Pollution Control Board
HAZOP Hazard and Operability Study
HDPE High Density Polyethylene
HSD High Speed Diesel
HSE Health, Safety and Environment
IMD Indian Meteorological Department
INR Indian Rupees
KLD Kilo Litre per Day
LU Land Use
ML Mining Lease
MoEF Ministry of Environment and Forest
MSDS Material Safety Data Sheet
MSL Mean Sea Level
MT Metric Tonnes
NABET National Accreditation Board for Education and Training
NDT Non Destructive Testing
NMHC Non-Methane Hydrocarbons
NOC No-Object Certificates (Consent to Establish)
NOx Nitrogen Oxides
OOIP original oil in-place
ONGC Oil and Natural Gas Corporation Limited
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OMR Oil Mines Regulation
PDCR Plan, Do, Check and Review
PEL Petroleum Exploration License
PM Particulate Matter
PPE Personal Protective Equipment
PSC Production Sharing Contract
SAR Sodium Absorption Ratio
SO2 Sulphur Dioxide
TDS Total Dissolved Solids
TSDF Treatment, Storage, and Disposal Facility
USEPA United States Environment Protection Agency
VOCs Volatile Organic Compounds
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GLOSSARY
ABANDONED WELL: A dry hole in which no producible oil or gas was present, or a well that has stopped
producing. Abandoned wells must be plugged to prevent seepage of oil, gas, or water from one formation
to another.
ACCIDENT: An accident may be defined as ’an undesirable and unplanned event with or without or major
or minor damage consequence to life and/or property.’
ACTIVE WELL: A well in mechanical condition for production or service use (i.e., in active production or
service use).
API: It is the short form of American Petroleum Institute. It is the oil industry’s trade organization. API’s
research and engineering work provides a basis for establishing operating and safety standard issues;
specifications for the manufacturing of oil field equipment; and furnishes statistical and other information
to related agencies.
ASSOCIATED GAS: Gas combined with oil or dissolved in crude oil. Known also as cap gas and solution
gas, it provides the drive mechanism needed to force oil to the surface of a well. Associated gas is
normally present in an oil reservoir in the early stages of production.
BARREL: The standard unit of measure of liquids in the petroleum industry. It is equivalent to 42 U.S.
standard gallons or 159 litres of oil.
BARREL OF OIL EQUIVALENT (BOE): The amount of energy resource that is equal to one barrel of oil
on an energy basis. The conversion is based on the assumption that one barrel of oil produces the same
amount of energy when burned as 5,620 cubic feet of natural gas.
BASIN: A depression of the earth’s surface into which sediments are deposited, usually characterized
by sediment accumulation over a long interval; a broad area of the earth beneath which layers of rock
are inclined, usually from the sides toward the centre.
BED: A layer of rock, usually sediments, which is homogeneous (the same) in composition. One bed is
separated from another by a bedding plane.
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BID: An offer for a lease submitted by a potential lessee in the form of a cash bonus dollar amount or
other commitments as specified in the final notice of sale.
BLEVE: (BOILING LIQUID EXPANDING VAPOUR EXPLOSION): This is a type of explosion that can
occur when a vessel containing a pressurized liquid is ruptured. Such explosions can be extremely
hazardous.
BLOWOUT: An uncontrolled flow of gas, oil, or other fluids from a well to the atmosphere. A well may
blow out when formation pressure exceeds the pressure overburden of a column of drilling fluid.
BLOWOUT PREVENTER: A special assembly of heavy-duty valves, commonly called the BOP stack,
installed on top of a well which can be closed to prevent high-pressure oil or gas from escaping (a
blowout) from the well hole during drilling operations.
BOREHOLE: The hole in the earth made by the drill; the uncased drill hole from the surface to the bottom
of the well.
CASING: Steel pipe used in oil wells to seal off fluids in the rocks from the bore hole and to prevent the
walls of the hole from caving.
CASING HEAD: The top of the casing set in a well; the part of the casing that protrudes above the surface
and to which the control valves and flow pipes are attached.
CASING HEAD GAS: Gas produced from an oil well as distinguished from gas from a gas well. The
casing head gas is taken off at the top of the well or at the separator.
COMMERCIAL WELL: A well of sufficient net production that it could be expected to pay out in a
reasonable time and yield a profit from the operation.
COMPLETED WELL: A well that has been mechanically completed for production or service use. There
may be more than one completed zone in the well.
CONDENSATE: A natural gas with a low vapour pressure compared with natural gasoline and liquefied
petroleum gas. It is produced from a deep well where the temperature and pressure are high. Gas
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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condenses as it rises up the well bore and reaches the surface as condensate. Similarly, condensate
separates out naturally in pipelines or in a separation plant by the normal process of condensation.
DEVELOPMENT: Activities following exploration including the installation of facilities and the drilling and
completion of wells for production purposes.
DIRECTIONAL DRILLING: The technique of drilling at an angle from the vertical by deflecting the drill
bit. Directional wells are drilled to develop an offshore lease from one drilling platform; to reach a pay
zone where drilling cannot be done, such as beneath a shipping lane.
DISASTER: Is a catastrophic consequence of a major emergency/accident that leads to, not only
extensive damage to life and property but also disrupts all normal human activity for a long time and
requires a major national and international effort for rescue and rehabilitation of those affected.
DISCOVERY: A find of significant quantity of gas or oil.
DRILL CUTTINGS: Chips and small fragments of drilled rock that are brought to the surface by the flow
of the drilling mud as it is circulated.
DRILL PIPE: Heavy, thick walled, hollow steel pipe used in rotary drilling to turn the drill bit and to provide
a conduit for the drilling mud.
DRILLING CONTRACTOR: A person or company whose business is drilling wells. Wells are drilled on
several contract specifications: per foot, day rate, or turnkey (that is, upon completion). Most major oil
companies do not own drilling rigs. Exploration and development drilling is contracted. Personnel
manning the rigs work for the contractor.
DRILLING MUD: A special mixture of clay, water, or refined oil, and chemical additives pumped down
through the drill pipe and drill bit. The mud cools the rapidly rotating bit; lubricates the drill pipe as it turns
in the well bore; carries rock cuttings to the surface; serves as a plaster to prevent the wall of the borehole
from crumbling or collapsing; and provides the weight or hydrostatic head to prevent extraneous fluids
from entering the well bore and to control down hole pressures that may be encountered.
DRY HOLE: A well drilled to a certain depth without finding commercially exploitable hydrocarbons.
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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DRY GAS: Natural gas from the well that is free of liquid hydrocarbons; gas that has been treated to
remove all liquids; pipeline gas.
EMERGENCY: Is a situation of process deviation that if uncontrolled may lead to a major
accident/disaster with potential short term and/or long term risk damage consequence to life and property
in and/or around the facility.
ENVIRONMENTAL IMPACT ASSESSMENT: A statement required under the Environmental Impact
Assessment Notification, 2006 or similar regulations by other bodies in relation to any action significantly
affecting the environment, including certain exploration and drilling activities.
EXPLORATION: The process of searching for minerals preliminary to development. Exploration activities
include (1) geophysical surveys, (2) drilling to locate an oil or gas reservoir, and (3) the drilling of additional
wells after a discovery to delineate a reservoir. It enables the lessee to determine whether to proceed
with development and production.
EXPLOSION: An explosion is a sudden increase in volume and release of energy in an extreme manner,
usually with the generation of high temperatures and the release of gases.
FIELD: A geographical area in which one or more oil or gas wells produce. A field may refer to surface
area only or to underground productive formation. A single field may include several reservoirs separated
either horizontally or vertically.
FIREBALL: The burning of a flammable gas cloud on being immediately ignited at the edge before
forming a flammable/explosive mixture.
FLAMMABLE LIMIT: Flammable limits refer to the conditions under which a mixture of a flammable
material and air may catch fire or explode. When vapour s of a flammable or combustible liquid are mixed
with air in the proper proportions in the presence of a source of ignition, rapid combustion or an explosion
can occur. The proper proportion is called the flammable range and is also often referred to as the
explosive range. The flammable range includes all concentrations of flammable vapour or gas in air, in
which a flash will occur or a flame will travel if the mixture is ignited.
FLASH FIRE: A flammable gas release getting ignited at the farthest edge resulting in flash-back fire.
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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Gas Lost: Natural gas which is flared or vented (i.e., natural gas not retained in the production system
for sale or use).
HAZARD: Is the potential of an Accident.
INCIDENT: Is an emergent situation of any critical deviation in the process control or otherwise that may
lead to a major accident/potential emergency and disaster.
LEASE: A legal document executed between a landowner (as lessor) and a company or individual (as
lessee) that conveys the right to exploit the premises for minerals or other products for a specified period
of time over a given area.
INJURY ZONE: Zone of injury in any hazardous event.
MAJOR ACCIDENT HAZARD (MAH) INDUSTRY: If the quantity of any chemical as listed in MSIHC
Rules’ Schedule-2 or Schedule-3 is equal to or greater than the Threshold Quantity given therein.
MAJOR ACCIDENT: Loss of life or 10 or more injuries on-site or 1 or more injuries off-site (as defined in
MSIHC Rules).
OIL LOST: Oil that is spilled or burned (i.e., oil not retained in the production system for sale).
OPERATOR: The individual, partnership, firm, or corporation having control or management of
operations on a leased area or a portion thereof. The operator may be a lessee, designated agent of the
lessee, holder of rights under an approved operation agreement, or an agent of an operating rights holder.
PLUGGED AND ABANDONED: Wells in which casings have been removed, and the well bore sealed
with mechanical or cement plugs.
PLUMES: Plumes are continuous release of hazardous gases and vapours. Smoke from a chimney is
an example. Plumes can cause Fires and Explosions as secondary scenarios, in case the gases are
flammable & ignition occurs.
PRODUCIBLE LEASE: A lease where one well or several wells have discovered hydrocarbons in paying
quantities, but for which there is no production during the reporting period.
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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PRODUCIBLE ZONE COMPLETION: The interval in a well bore that has been mechanically prepared
to produce oil, gas or sulphur. There can be more than one zone completed for production in a well bore.
PRODUCING LEASE: A lease that is producing oil, gas, or sulphur in quantities sufficient to generate
royalties.
PRODUCTION: The phase of oil and gas operations involved with well fluids extraction, separation,
treatment, measurement, etc.
PROVEN RESERVES (SOCIETY OF PETROLEUM ENGINEERS): Reserves that can be estimated with
reasonable certainty to be recovered under current economic conditions. Current economic conditions
include processing costs prevailing at the time of the estimate. Proved reserves must either have facilities
that are operational at the time of the estimate to process and transport those reserves to market, or a
commitment of reasonable expectation to install such facilities in the future. Proved reserves can be
subdivided into undeveloped and developed Reserves.
PUFFS: Puffs are instantaneous release of hazardous gases and vapours. Puffs can give rise to FIRE
BALLS and vapour cloud explosions (VCE). A special case of vapour cloud explosion is the Boiling Liquid
Evaporating Vapour Explosion (BLEVE).
RENT: Periodic payments made by the holder of a lease, during the primary lease term for the right to
use the land or resources for purposes established in the lease.
ROYALTY: Payment, in value (money) or in kind, of a stated proportionate interest in production from
mineral deposits by the lessees to the Government.
SALES VALUE: The proceeds received for the sale of the mineral.
SERVICE ZONE COMPLETION: The interval in a well bore that has been mechanically prepared for
service use, usually water or gas injection to stimulate production from other wells or for water or other
waste disposal.
SESMIC SURVEY: The seismic survey is one form of geophysical survey that aims at measuring the
earth’s (geo-) properties by means of physical (-physics) principles such as magnetic, electric,
gravitational, thermal, and elastic theories
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SPILLS: Spills are liquid pools created by leaking liquid chemicals. Spills may cause evaporation and
dispersal of toxic gases and if the spilled liquid is flammable, then it can catch fire creating a pool fire, or
the vapour can cause explosion.
SUSPENDED WELL: A well on which operations have been discontinued. The usual context is an
uncompleted well in which operations ceased during drilling but which has not been plugged and
abandoned permanently.
UPPER EXPLOSIVE LIMIT (UEL)/ UPPER FLAMMABILE LIMIT (UFL): Upper flammable limit (UEL) or
the upper explosive limit is the maximum concentration of vapour or gas in air below which propagation
of flame does not occur on contact with a source of ignition. The mixture is said to be too rich.
LOWER EXPLOSIVE LIMIT (LEL)/ LOWER FLAMMABILE LIMIT (LFL): Lower flammable limit (LEL)
or the lower explosive limit is the minimum concentration of vapour or gas in air above which propagation
of flame does not occur on contact with a source of ignition. The mixture is said to be too lean.
VCE: (VAPOUR CLOUD EXPLOSION); Explosion resulting from vapour clouds formed from flashing
liquids or non-flashing liquids and gases. Sometimes also referred to as unconfined vapour cloud
explosion.
VULNERABILITY ZONE: Zone of Exposure leading to Fatality or recoverable injury in any hazardous
event.
WELL: A hole drilled or bored into the earth, usually cased with metal pipe, for the production of gas or
oil. A hole for the injection under pressure of water or gas into a subsurface rock formation.
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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ABBREVIATIONS
BLEVE Boiling Liquid Evaporating Vapour Explosion
BOD Biological Oxygen Demand
BOP Blow-out Preventer
CAGR Compounded Annual Growth Rate
CC&A Common Consent and Authorization (Consent to Operate (for water and air emissions) and Authorization (for management of hazardous wastes)
CGWA Central Ground Water Authority
COD Chemical Oxygen Demand
CPCB Central Pollution Control Board
DG Diesel Generator
DGH Directorate General of Hydrocarbons
DMP Disaster Management Plan
EC Environmental Clearance
ECC Emergency Control Centre
EHS Environmental Health and Safety
EIA Environmental Impact Assessment
EMP Environmental Management Plan
EOR Enhanced oil Recovery
FAE Functional Area Expert
GGS Group Gathering Stations
GLC Ground Level Concentration
GoI Government of India
GPCB Gujarat Pollution Control Board
HAZOP Hazard and Operability Study
HDPE High Density Polyethylene
HSD High Speed Diesel
HSE Health, Safety and Environment
IMD Indian Meteorological Department
INR Indian Rupees
KLD Kilo Litre per Day
LU Land Use
ML Mining Lease
MoEF Ministry of Environment and Forest
MSDS Material Safety Data Sheet
MSL Mean Sea Level
MT Metric Tonnes
NABET National Accreditation Board for Education and Training
NDT Non Destructive Testing
NMHC Non-Methane Hydrocarbons
NOC No-Object Certificates (Consent to Establish)
NOx Nitrogen Oxides
OOIP original oil in-place
ONGC Oil and Natural Gas Corporation Limited
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
Doc. No. ONGC/CHSE/EIA/WOB/2018-19/01
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Chapter No. Abbreviations & Glossary
ii
OMR Oil Mines Regulation
PDCR Plan, Do, Check and Review
PEL Petroleum Exploration License
PM Particulate Matter
PPE Personal Protective Equipment
PSC Production Sharing Contract
SAR Sodium Absorption Ratio
SO2 Sulphur Dioxide
TDS Total Dissolved Solids
TSDF Treatment, Storage, and Disposal Facility
USEPA United States Environment Protection Agency
VOCs Volatile Organic Compounds
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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Chapter No. Abbreviations & Glossary
iii
GLOSSARY
ABANDONED WELL: A dry hole in which no producible oil or gas was present, or a well that has stopped
producing. Abandoned wells must be plugged to prevent seepage of oil, gas, or water from one formation
to another.
ACCIDENT: An accident may be defined as ’an undesirable and unplanned event with or without or major
or minor damage consequence to life and/or property.’
ACTIVE WELL: A well in mechanical condition for production or service use (i.e., in active production or
service use).
API: It is the short form of American Petroleum Institute. It is the oil industry’s trade organization. API’s
research and engineering work provides a basis for establishing operating and safety standard issues;
specifications for the manufacturing of oil field equipment; and furnishes statistical and other information
to related agencies.
ASSOCIATED GAS: Gas combined with oil or dissolved in crude oil. Known also as cap gas and solution
gas, it provides the drive mechanism needed to force oil to the surface of a well. Associated gas is
normally present in an oil reservoir in the early stages of production.
BARREL: The standard unit of measure of liquids in the petroleum industry. It is equivalent to 42 U.S.
standard gallons or 159 litres of oil.
BARREL OF OIL EQUIVALENT (BOE): The amount of energy resource that is equal to one barrel of oil
on an energy basis. The conversion is based on the assumption that one barrel of oil produces the same
amount of energy when burned as 5,620 cubic feet of natural gas.
BASIN: A depression of the earth’s surface into which sediments are deposited, usually characterized
by sediment accumulation over a long interval; a broad area of the earth beneath which layers of rock
are inclined, usually from the sides toward the centre.
BED: A layer of rock, usually sediments, which is homogeneous (the same) in composition. One bed is
separated from another by a bedding plane.
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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Chapter No. Abbreviations & Glossary
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BID: An offer for a lease submitted by a potential lessee in the form of a cash bonus dollar amount or
other commitments as specified in the final notice of sale.
BLEVE: (BOILING LIQUID EXPANDING VAPOUR EXPLOSION): This is a type of explosion that can
occur when a vessel containing a pressurized liquid is ruptured. Such explosions can be extremely
hazardous.
BLOWOUT: An uncontrolled flow of gas, oil, or other fluids from a well to the atmosphere. A well may
blow out when formation pressure exceeds the pressure overburden of a column of drilling fluid.
BLOWOUT PREVENTER: A special assembly of heavy-duty valves, commonly called the BOP stack,
installed on top of a well which can be closed to prevent high-pressure oil or gas from escaping (a
blowout) from the well hole during drilling operations.
BOREHOLE: The hole in the earth made by the drill; the uncased drill hole from the surface to the bottom
of the well.
CASING: Steel pipe used in oil wells to seal off fluids in the rocks from the bore hole and to prevent the
walls of the hole from caving.
CASING HEAD: The top of the casing set in a well; the part of the casing that protrudes above the surface
and to which the control valves and flow pipes are attached.
CASING HEAD GAS: Gas produced from an oil well as distinguished from gas from a gas well. The
casing head gas is taken off at the top of the well or at the separator.
COMMERCIAL WELL: A well of sufficient net production that it could be expected to pay out in a
reasonable time and yield a profit from the operation.
COMPLETED WELL: A well that has been mechanically completed for production or service use. There
may be more than one completed zone in the well.
CONDENSATE: A natural gas with a low vapour pressure compared with natural gasoline and liquefied
petroleum gas. It is produced from a deep well where the temperature and pressure are high. Gas
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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Chapter No. Abbreviations & Glossary
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condenses as it rises up the well bore and reaches the surface as condensate. Similarly, condensate
separates out naturally in pipelines or in a separation plant by the normal process of condensation.
DEVELOPMENT: Activities following exploration including the installation of facilities and the drilling and
completion of wells for production purposes.
DIRECTIONAL DRILLING: The technique of drilling at an angle from the vertical by deflecting the drill
bit. Directional wells are drilled to develop an offshore lease from one drilling platform; to reach a pay
zone where drilling cannot be done, such as beneath a shipping lane.
DISASTER: Is a catastrophic consequence of a major emergency/accident that leads to, not only
extensive damage to life and property but also disrupts all normal human activity for a long time and
requires a major national and international effort for rescue and rehabilitation of those affected.
DISCOVERY: A find of significant quantity of gas or oil.
DRILL CUTTINGS: Chips and small fragments of drilled rock that are brought to the surface by the flow
of the drilling mud as it is circulated.
DRILL PIPE: Heavy, thick walled, hollow steel pipe used in rotary drilling to turn the drill bit and to provide
a conduit for the drilling mud.
DRILLING CONTRACTOR: A person or company whose business is drilling wells. Wells are drilled on
several contract specifications: per foot, day rate, or turnkey (that is, upon completion). Most major oil
companies do not own drilling rigs. Exploration and development drilling is contracted. Personnel
manning the rigs work for the contractor.
DRILLING MUD: A special mixture of clay, water, or refined oil, and chemical additives pumped down
through the drill pipe and drill bit. The mud cools the rapidly rotating bit; lubricates the drill pipe as it turns
in the well bore; carries rock cuttings to the surface; serves as a plaster to prevent the wall of the borehole
from crumbling or collapsing; and provides the weight or hydrostatic head to prevent extraneous fluids
from entering the well bore and to control down hole pressures that may be encountered.
DRY HOLE: A well drilled to a certain depth without finding commercially exploitable hydrocarbons.
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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Chapter No. Abbreviations & Glossary
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DRY GAS: Natural gas from the well that is free of liquid hydrocarbons; gas that has been treated to
remove all liquids; pipeline gas.
EMERGENCY: Is a situation of process deviation that if uncontrolled may lead to a major
accident/disaster with potential short term and/or long term risk damage consequence to life and property
in and/or around the facility.
ENVIRONMENTAL IMPACT ASSESSMENT: A statement required under the Environmental Impact
Assessment Notification, 2006 or similar regulations by other bodies in relation to any action significantly
affecting the environment, including certain exploration and drilling activities.
EXPLORATION: The process of searching for minerals preliminary to development. Exploration activities
include (1) geophysical surveys, (2) drilling to locate an oil or gas reservoir, and (3) the drilling of additional
wells after a discovery to delineate a reservoir. It enables the lessee to determine whether to proceed
with development and production.
EXPLOSION: An explosion is a sudden increase in volume and release of energy in an extreme manner,
usually with the generation of high temperatures and the release of gases.
FIELD: A geographical area in which one or more oil or gas wells produce. A field may refer to surface
area only or to underground productive formation. A single field may include several reservoirs separated
either horizontally or vertically.
FIREBALL: The burning of a flammable gas cloud on being immediately ignited at the edge before
forming a flammable/explosive mixture.
FLAMMABLE LIMIT: Flammable limits refer to the conditions under which a mixture of a flammable
material and air may catch fire or explode. When vapour s of a flammable or combustible liquid are mixed
with air in the proper proportions in the presence of a source of ignition, rapid combustion or an explosion
can occur. The proper proportion is called the flammable range and is also often referred to as the
explosive range. The flammable range includes all concentrations of flammable vapour or gas in air, in
which a flash will occur or a flame will travel if the mixture is ignited.
FLASH FIRE: A flammable gas release getting ignited at the farthest edge resulting in flash-back fire.
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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Gas Lost: Natural gas which is flared or vented (i.e., natural gas not retained in the production system
for sale or use).
HAZARD: Is the potential of an Accident.
INCIDENT: Is an emergent situation of any critical deviation in the process control or otherwise that may
lead to a major accident/potential emergency and disaster.
LEASE: A legal document executed between a landowner (as lessor) and a company or individual (as
lessee) that conveys the right to exploit the premises for minerals or other products for a specified period
of time over a given area.
INJURY ZONE: Zone of injury in any hazardous event.
MAJOR ACCIDENT HAZARD (MAH) INDUSTRY: If the quantity of any chemical as listed in MSIHC
Rules’ Schedule-2 or Schedule-3 is equal to or greater than the Threshold Quantity given therein.
MAJOR ACCIDENT: Loss of life or 10 or more injuries on-site or 1 or more injuries off-site (as defined in
MSIHC Rules).
OIL LOST: Oil that is spilled or burned (i.e., oil not retained in the production system for sale).
OPERATOR: The individual, partnership, firm, or corporation having control or management of
operations on a leased area or a portion thereof. The operator may be a lessee, designated agent of the
lessee, holder of rights under an approved operation agreement, or an agent of an operating rights holder.
PLUGGED AND ABANDONED: Wells in which casings have been removed, and the well bore sealed
with mechanical or cement plugs.
PLUMES: Plumes are continuous release of hazardous gases and vapours. Smoke from a chimney is
an example. Plumes can cause Fires and Explosions as secondary scenarios, in case the gases are
flammable & ignition occurs.
PRODUCIBLE LEASE: A lease where one well or several wells have discovered hydrocarbons in paying
quantities, but for which there is no production during the reporting period.
Onshore Oil & Gas Exploration of 46 wells in 12 ML Blocks of Western Onshore Basin , District Mehsana, Gujarat
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PRODUCIBLE ZONE COMPLETION: The interval in a well bore that has been mechanically prepared
to produce oil, gas or sulphur. There can be more than one zone completed for production in a well bore.
PRODUCING LEASE: A lease that is producing oil, gas, or sulphur in quantities sufficient to generate
royalties.
PRODUCTION: The phase of oil and gas operations involved with well fluids extraction, separation,
treatment, measurement, etc.
PROVEN RESERVES (SOCIETY OF PETROLEUM ENGINEERS): Reserves that can be estimated with
reasonable certainty to be recovered under current economic conditions. Current economic conditions
include processing costs prevailing at the time of the estimate. Proved reserves must either have facilities
that are operational at the time of the estimate to process and transport those reserves to market, or a
commitment of reasonable expectation to install such facilities in the future. Proved reserves can be
subdivided into undeveloped and developed Reserves.
PUFFS: Puffs are instantaneous release of hazardous gases and vapours. Puffs can give rise to FIRE
BALLS and vapour cloud explosions (VCE). A special case of vapour cloud explosion is the Boiling Liquid
Evaporating Vapour Explosion (BLEVE).
RENT: Periodic payments made by the holder of a lease, during the primary lease term for the right to
use the land or resources for purposes established in the lease.
ROYALTY: Payment, in value (money) or in kind, of a stated proportionate interest in production from
mineral deposits by the lessees to the Government.
SALES VALUE: The proceeds received for the sale of the mineral.
SERVICE ZONE COMPLETION: The interval in a well bore that has been mechanically prepared for
service use, usually water or gas injection to stimulate production from other wells or for water or other
waste disposal.
SESMIC SURVEY: The seismic survey is one form of geophysical survey that aims at measuring the
earth’s (geo-) properties by means of physical (-physics) principles such as magnetic, electric,
gravitational, thermal, and elastic theories
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SPILLS: Spills are liquid pools created by leaking liquid chemicals. Spills may cause evaporation and
dispersal of toxic gases and if the spilled liquid is flammable, then it can catch fire creating a pool fire, or
the vapour can cause explosion.
SUSPENDED WELL: A well on which operations have been discontinued. The usual context is an
uncompleted well in which operations ceased during drilling but which has not been plugged and
abandoned permanently.
UPPER EXPLOSIVE LIMIT (UEL)/ UPPER FLAMMABILE LIMIT (UFL): Upper flammable limit (UEL) or
the upper explosive limit is the maximum concentration of vapour or gas in air below which propagation
of flame does not occur on contact with a source of ignition. The mixture is said to be too rich.
LOWER EXPLOSIVE LIMIT (LEL)/ LOWER FLAMMABILE LIMIT (LFL): Lower flammable limit (LEL)
or the lower explosive limit is the minimum concentration of vapour or gas in air above which propagation
of flame does not occur on contact with a source of ignition. The mixture is said to be too lean.
VCE: (VAPOUR CLOUD EXPLOSION); Explosion resulting from vapour clouds formed from flashing
liquids or non-flashing liquids and gases. Sometimes also referred to as unconfined vapour cloud
explosion.
VULNERABILITY ZONE: Zone of Exposure leading to Fatality or recoverable injury in any hazardous
event.
WELL: A hole drilled or bored into the earth, usually cased with metal pipe, for the production of gas or
oil. A hole for the injection under pressure of water or gas into a subsurface rock formation.
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Point wise compliance of TOR for the Onshore Oil & Gas Exploration of 46 wells in 12 ML blocks in Mehsana District, Gujarat. MoEF&CC No. IA-J-11011/158/2018-IA-II (I) dated 01/06/2018.
Sl. No Terms of Reference Status
1. Executive summary of a project.
Executive Summary has been enclosed given in EIA report.
2. Project description, project objectives and project benefits.
Project description is given in Chapter-2, project objectives are given in section-2.4 of Chapter-2 and benefits of the project are given in Chapter-8.
3.
Cost of Project and Period of completion
The total estimated cost of the proposed Project is 460 crores. The implementation schedule for the proposed project will be approximately 3-4 months from date of EC.
4. Site details within 1 km of the each proposed well, any habitation, any other installation/activity, flora and fauna, approachability to site, other activities including agriculture/land, satellite imagery for 10 km area. All the geological details shall be mentioned in the Topo sheet of 1:40000 scale, superimposing the well locations and other structures of the projects. Topography of the project site.
Brief description of proposed Project is given in Table-1.1. The Topographic and Google map are shown in Figure-1.1 and Figure-1.2 of Chapter-1. Flora and fauna details are given in Section-3.11 of Chapter-3. land use pattern is given in Figure-3.6 of Chapter-3.
5. Details of sensitive areas such as National Park, Wildlife sanctuary and any other eco-sensitive area along with map indicating distance.
No Eco-senstive Zone found in the study area
6. Approval for the forest land from the State/Central Govt. under Forest (Conservation) Act, 1980, if applicable.
No Forest Area found in the Study Area
7. Recommendation of SCZMA/CRZ clearance as per CRZ Notification dated 6th January, 2011 ( if applicable).
Not Applicable
8. Distance from nearby critically/severely polluted area as per Notification, if applicable. Status of moratorium imposed on the area.
Nil
9. Does proposal involve rehabilitation and resettlement? If yes, details thereof
No
10.
Environmental considerations in the selection of the drilling locations for which environmental clearance is being sought.
Details are given in Section 2.4.2 of Chapter-2
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Present any analysis suggested for minimizing the foot print giving details of drilling and development options considered.
11. Baseline data collection for air, water and soil for one season leaving the monsoon season in an area of 10 km radius with center of Oil Field as its center covering the area of all proposed drilling wells.
The baseline studies were carried out from 27th April 2018 to 27th July 2018 representing Pre-monsoon Summer season. Details are given in Chapter-3 of EIA report.
12. Climatology and Meteorology including wind speed, wind direction, temperature rainfall relative humidity etc.
Climatology and Meteorological details are given in Section-3.6 of Chapter-3.
13. Details of Ambient Air Quality monitoring at 8 locations for PM2.5, PM10, SO2, NOx, CO, VOCs, Methane and non-methane HC.
Results of Ambient Air Quality monitoring are given in Section-3.8 of Chapter-3.
14. Soil sample analysis (physical and chemical properties) at the areas located at 5 locations.
Details of Soil Sampling analysis are given in Section-3.11 of Chapter-3.
15. Ground and surface water quality in the vicinity of the proposed wells site.
Surface water and ground water quality have been monitored and results are given in Section 3.10 of Chapter-3.
16. Measurement of Noise levels within 1 km radius of the proposed wells.
Noise level survey results are given in Section-3.9 of Chapter-3.
17. Vegetation and land use; flora/fauna in the block area with details of endangered species, if any
Details of flora and fauna are given in Section-3.12 of Chapter-3.
18. Incremental GLC as a result of DG set operation, flaring etc
Incremental GLC concentration results are mentioned in Section 4.2.1.3 of Chapter-4.
19. Potential environmental impact envisaged during various stages of project activities such as site activation, development, operation/ maintenance and decommissioning.
Impact assessment and mitigation measures for the stage wise proposed project activities are given in Chapter-4.
20. Actual source of water and 'Permission' for the drawl of water from the Competent Authority. Detailed water balance, wastewater generation and discharge.
The water requirement will be met from the local sources through ONGC Installations. Water requirement given in Section-2.5.1 of Chapter-2. Waste water generation details and mode of treatment are given in Section-2.5.3 of Chapter-2.
21. Noise abatement measures and measures to minimize disturbance due to light and visual intrusions.
Noise control measures are given in Section-4.2.2 of Chapter-4.
22. Details on wastewater generation, treatment and utilization /discharge for produced water/ formation water, cooling waters, other wastewaters, etc. during all project phases.
Wastewater generation details and mode of treatment are given in Section-2.5.3 of Chapter-2 and Section-4.2.9.3 of Chapter-4.
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23. Details on solid waste management for drill cuttings, drilling mud and oil sludge, produced sand, radioactive materials, other hazardous materials, etc. including its disposal options during all project phases.
Solid waste management details are given in Section-4.2.9.2 of Chapter-4.
24. Disposal of spent oil and lube
Management of used oil details are given in Section-2.5.5 of Chapter-2.
25. Storage of chemicals and diesel at site. Hazardous material usage, storage and accounting.
Details for storage of chemicals are given in Section-2.5.1 of Chapter-2.
26. Commitment for the use of water based mud (WBM) only
Water Based Mud (WBM) waste from drilling details are given in Section-4.2.9 of Chapter-4.
27. Oil spill emergency plans for recovery/ reclamation.
Oil spill emergency plan is given in Section-7.6.13 of Chapter-7.
28. H2S emissions control.
H2S emission control details are given in Section-7.6.3 of Chapter-7.
29. Produced oil/gas handling, processing and storage/transportation.
Exploratory Drilling no production at this stage
30. Details of control of air, water and noise pollution during production phase.
Not applicable
31. Measures to protect ground water and shallow aquifers from contamination.
Mitigation Measures to protect ground water and surface water are given in Section-4.2.3.3 & Section-4.2.3.4 of Chapter-4.
32. Whether any burn pits being utilized for well test operations.
Nil
33. Risk assessment and disaster management plan for independent reviews of well-designed construction etc. for prevention of blow out. Blowout preventer installation.
Risk and disaster management plan details are given in Section-7.2 and Section-7.4 of Chapter-7. Blow out emergency Response procedure details are given in Section -7.6.1.
34. Environmental management plan EMP details are given in chapter-10
35. Total capital and recurring cost for environmental control measures.
The estimated cost of the proposed exploration well drilling is Rs.3500 crores. The cost for environmental control measures has been included in the total project cost.
36. Emergency preparedness plan.
Details are given in disaster management plan in section-7.6 of chapter-7.
37. Decommissioning and restoration plans.
Details of decommissioning and restoration plans section-2.5.9 of chapter-2.
38. Documentary proof of membership of common disposal facilities, if any
Membership of common disposal facilities is under progress.
39. Details of environmental and safety related documentation within the company including documentation and proposed occupational
Occupational health and safety details are mentioned in Section 7.9 of Chapter-7.
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health and safety Surveillance Safety Programme for all personnel at site. This shall also include monitoring programme for the environmental.
40. A copy of Corporate Environment Policy of the company as per the Ministry's O.M. No. J-11013/ 41/2006-IA. II (I) dated 26th April, 2011 available on the Ministry's website.
Corporate Environment Policy of ONGC as shown in Annexure-II
41. Any litigation pending against the project and or any direction/order passed by any court of law against the project. If so details thereof.
Nil
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1.0 EXECUTIVE SUMMARY
Oil and Natural Gas Corporation Limited (ONGC) proposes to carryout onshore Exploration of oil &
gas in 46 exploratory wells in 12 ML Blocks of Western Onshore basin in Mehsana District of Gujarat
state. As per the Environment Impact Assessment (EIA) Notification dated 14th September 2006, the
proposed project falls under ‘Category A’ of Activity Type 1(b) requires prior Environmental Clearance
(EC) to be obtained from MoEF&CC before the commencement of ground activity. The application for
prior EC (Form-1 and Pre-feasibility Report) for the Exploration of oil and gas in 46 wells (Onshore) of 12
ML Blocks of Western Onshore Basin has been submitted to MoEF&CC on 25th April 2018 and Terms of
Reference (TOR) has been issued by MoEF&CC vide letter reference F. No. IA-J-11011/158/2018-IA-II
(I) and Proposal No. IA/GJ/IND2/74678/2018 dated 1st June 2018.
1.1 Details of the Project
ONGC proposes onshore Exploration of oil & gas in 12 blocks in Mehsana District, Gujarat. The salient
features of the project are given in Table 1. The blocks details are given in Table-2
Table 1: Salient Features of the project
S.No. Particulars Details 1. Name of Blocks Jotana ML-; Linch ML; Linch Ext – I ML ;
Nandasan Langnaj ML ; North Shobhasan Ext – I ML ; Jotana – Warason ML; Kadi ML ;Linch Ext – II ML; Mansa ML; Jakasana ML; East Shobhasan ML ; and Balol Ext. I ML .
2. District Mehsana
3. State Gujarat
4. Geographical location in toposheet 46A-2, 46 A-6, 46 A-7, 46 A-11
5. Total Area of the Project 448.89 sq.km
6. Total Cost of the Project 460 Crores
7. Nearest railway station along with distance in kms
Mehsana, 04 km
8. Nearest airport along with distance in kms
Ahmedabad, 60 km
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9. Protected areas as per Wildlife Protection Act,1972 (Tiger reserve, Elephant reserve, Biospheres, National parks, Wildlife sanctuaries, community reserves and conservation reserves)
Not found in the study area
10. Reserved / Protected Forests Not found in the study area
11. Seismicity Zone-III
Table-2 Block details of the study area SL. No.
Name of Block No. of Proposed Wells in each block
Block Area (sq. km)
1 Jotana ML 3 39.50
2 Linch ML 4 43.73
3 Linch Ext – I ML 7 34.25
4 Nandasan Langnaj ML 3 61.90
5 North Shobhasan Ext – I ML 1 56.85
6 Jotana – Warason ML 4 38.05
7 Kadi ML 14 64.49
8 Linch Ext – II ML 2 13.35
9 Mansa ML 2 58.72
10 Jakasana ML 1 9.8
11 East Shobhasan ML 2 22.42
12 Balol Ext. I ML 2 5.83
Total 46 448.89
The details of environmental setting for 10 km radius of the project block area are given below.
The project block is connected through State Highways SH41/SH 19and Mehsana railway
station within ML area;
1.2 Importance of the Proposed Project
India is not among the major producers of crude oil, as it does not have much oil reserves.
Therefore, India depends on imports of crude oil from other countries. There is a heavy imbalance
between oil production and consumption in India. The Indian government is encouraging
exploration and production of oil and gas to a great extent. This would primarily allow India to tap
its own resources there by reducing its import bill. Discovery of viable hydrocarbon reserves in
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the state can boost the state’s economic development to a great extent. The proposed project is
therefore immensely significant for the state and nation.
1.3 Details of Proposed Project
The onshore exploration of oil & gas in the delineated area selected through seismic survey to identify
and establish hydrocarbon potential. The site will be sized to contain all equipment and temporary camps,
storage, workshops, etc. using distances between various rig components in line with existing rules and
regulations for the area of operation and the approved standard operating procedures of the drilling
contractor. Within the above constraints, the site shall be sized to minimize environmental impact. The
approximate area of well site is dependent on the type of drilling equipment deployed, which in turn is
dictated by the planned depth of drilling.
1.4 Manpower Arrangement
During the drilling operations, about 10 to 12 persons may be working in 8/12 hour shifts at site. Workers
will be able to return to their camp/homes during duty – off period. Once drilling is over no person is
required at site, except security cover through a contractor.
1.5 Land Requirement
ONGC shall acquire the land apprx. 110m x 110m per well on temporarily basis for the purpose of
preparation of the drill site and drilling operations. The site may require temporary approach road from
an existing one for transportation of rig and other equipment necessary for drilling work. The site shall be
fenced in the event the well is successful. The well site shall be reduced to approximately 30m x 30m for
the production phase and all non-essential areas shall be fully reclaimed as per ONGC’s restoration policy
and land handed over to the land owner.
1.6 Power Requirement
During drilling operations, diesel engines shall be utilized as prime movers for meeting the power required
to run the drilling rig, circulation system etc. A power generator shall also be installed for lighting. The
capacity of the diesel engines that shall be used for operating the rig and the circulation system is
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expected to be of 1250HP (3 Nos, two running and one standby), which will be run by High Speed Diesel.
This generator shall consume approximately 2.5 to 3 KLD of fuel per day, when in operation.
1.7 Water Requirement
The most significant requirement of water for drilling activities is for mud preparation. The other
requirement would be for engine cooling, floor / equipment / string washing, sanitation, fire-fighting
storage / make-up and drinking. During the drilling activity, about 25 m3 per day water will be required
which will include requirements for operation and that for sanitation and drinking of the workers during
drilling single well. The water shall be made available from the nearest ONGC installation, and will be
transported by water tanker. A water pit of approx.100 m3 capacity will be constructed at the site for the
purpose of fire fighting.
2.0 Baseline Environmental Status
Environmental monitoring has been carried within the entire 12 blocks for onshore Exploration of oil &
gas in Mehsana district, Gujarat. The baseline carried out during summer season (27th April to 27th July
2018).
2.1 Land Use Studies
The land use pattern of the proposed project has been studied by District Census Hand Books and satellite
images. The land use pattern of the study area indicates the 84.98 % of land comprises of Agriculture,
Crop Land ( 284089 hectare ), 3.51 % is Agriculture, fallow ( 11726 hectare ), 3.29 % is scrub land (10928
hectare), followed by water bodies (8419 hectare), built up land (8970 hectare) and water bodies (5701
hectare)
2.2 Soil Quality
The soil samples were tested at 8 locations covering various land uses. It has been observed that the pH
of the soil is ranging from 6.49 to 7.48 indicating that the soil is slightly acidic to slightly alkaline in nature.
Moisture found in the range from 0.98 to 1.47%. Conductivity of the soil ranges from 0.078 to 0.672
mS/cm. Texture of the soil in the selected locations of study area were observed to be silty, sandy and
clay loamy in nature. The potassium content varies from 1618 to 3649 kg/ha. Exchangeable Sodium
content varies from 4.15 to10.3 m.eq/100g. Exchangeable calcium and Exchangeable magnesium were
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found in the range between 4.51 to 154 m.eq/100g & 7.3 to 14.3 m.eq/100g respectively. The available
Phosphorous as P ranges from 13.7 kg/ha to 54.7 kg/ha. The available Nitrogen content varies from 207
kg/ha to 346 kg/ha. The Total Nitrogen in the soil is from 271 kg/ha to 505 kg/ha.
2.3 Meteorology
On-site monitoring was undertaken for various meteorological variables in order to generate the site-
specific data. The data generated is then compared with the meteorological data generated by nearest
India Meteorological Department (IMD) stations, located at Ahmedabad.
Meteorological data shows that mean average wind speed during study period are 1.675 m/s while wind
blows from SW direction and Average maximum temperature 39.05°C and minimum temperature 27.5°C
The mean average of maximum relative humidity recorded was 75.5% while mean minimum of 43%.
2.4 Ambient Air Quality
To establish the baseline status of the ambient air quality in the study area, the air quality was monitored
at 11 locations. Out of the 11 locations the minimum and maximum concentration for PM10 ranges between
41.2 and 80.4 g/m3 which are well within the NAAQ standards i.e. 100 g/m3. The minimum and maximum
concentration PM2.5 varies between 18.6 to 45.1 g/m3 respectively during the study period which are well
within the NAAQ standards i.e. 60 g/m3. The concentrations of SO2 ranges between 5.1 to 14.1 g/m 3
which are well within the NAAQ standards i.e. 80 g/m3.The concentrations of NOx were varied between
5.7 to 24.6 g/m3 respectively which are well within the NAAQ standard i.e. 80 g/m3. CO were observed
to be in the range of 0.10 mg/m3 to 0.39 mg/m3. Methane hydrocarbon (CH4 HC) was observed to be below
the detection limit of 0.1 g/m3. Non-methane hydrocarbon (Non-CH4 HC) was observed to be below the
detection limit of 0.1 g/m3. From the analysis of the monitored data, it infers that the air quality levels in
the study area are of fairly good quality and comply with the National Ambient Air Quality Standards
(NAAQ).
2.5 Ambient Noise Level
The noise monitoring has been conducted at 95 locations, covering residential, commercial and silence
zones in the study area. During Day Time the maximum noise level was observed as 55.7 dB (A) dB at
Palavasana part and a minimum of 48.7dB (A) was observed at near Indrap. While During Night time a
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maximum of 42 dB (A) was observed near Indrap, Linch and Lanva and a minimum of 38.4 dB (A) was
observed at Jakasana. A review of this data indicates that at all the locations, the noise level was found
within the permissible limits according to the rule S.O.50 (E), [11/01/2010] - The Noise Pollution
(Regulation and Control) (Amendment) Rules, 2010 except Palavasana part which is a satellite township
of Mehsana town and hence this is due to heavy vehicular traffic in the region.
2.6 Water Quality
The baseline water quality status in the region is established by analysing about 07 ground water samples
and 14 surface water samples during study period.
Ground Water
The pH value of the collected ground water in the study area found to be in the range from 7.57 to 8.01
and conductivity observed in the range 863 µS/cm to 2680 µS/cm. TDS values were observed to be in
range from 480 mg/L to 1512 mg/ L. Total alkalinity is found to be the range from 250 mg/L to 330 mg/L
and Total Hardness ranges from 228 to 560 mg/L. The chloride values of the samples were observed
from 105 mg/L to 645 mg/L and Sulphate values were observed from 8 mg/L to 128 mg/L. The Calcium
and magnesium values were ranged from 43 mg/L to 104 mg/L and 27 mg/L to 73 mg/L respectively. Iron
content observed in the range from BDL (<0.05) mg/l to 0.3 mg/l. Most of the metals are observed as
below the detection limit. Total Coliforms were observed between less than 2MPN/100ml and 26
MPN/100ml and Feacal Coliforms were observed to be less than 2 MPN/100ml.
Surface Water
The pH value of the collected surface water in the study area found to be in the range from 6.61 to 7.52
and conductivity observed in the range 270 µS/cm to 2220 µS/cm. TDS values were observed to be in
range from 184 mg/L to 1288 mg/ L. Total alkalinity is found to be the range from 121mg/L to 391mg/L
and Total Hardness ranges from 112 to 450 mg/L. The chloride values of the samples were observed
from 32 mg/L to 407 mg/L and Sulphate values were observed from 8 mg/L to 120 mg/L. The Calcium
and magnesium values were ranged from 16 mg/L to 108 mg/L and 12.5 mg/L to 46 mg/L respectively.
Iron content observed in the range from 0.26 mg/L to 5.46 mg/L. COD values observed between 12 mg/L
to 60 mg/L. Most of the metals are observed to be within the detection limit. Total Coliforms were
observed Between 17 MPN/100ml and 900 MPN/100ml and Fecal Coliforms were observed between 4
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MPN/100ml to 80 MPN/100ml.Based on the analyzed parameters, it can be concluded that above surface
water is not fit for drinking purposes unless it is treated and disinfected.
2.7 Biological Environment
As per primary survey and secondary data referred, it can be concluded that the study area is ecologically
rich and diverse.The geography of Mehsana district 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 nilgai, chitals, wild boar, four horned antelope and camels etc. A large number of other animals
like snakes, lizards, scorpions, bees, etc., are found in the study area. Many kinds of birds are found
here, such as:, Peacock, Parrots, pheasants, geese ducks and cranes, etc.
Flora in Mehsana district include a wide variety of vegetation. A wide range of climatic condition facilitates
the prevalence of many types of flora., during survey various species of flora are found in one of the
largest dry deciduous forests in the western region of India, including trees like:teak, Boswellia serrata,
Anogeissus latifolia and Diospyros, etc.Owing to the arid climate, the flora and fauna of Gujarat also
possess a wide range of xerophytic vegetation. This kind of vegetation include Acacia Arabica, Acacia
leucophloea, Capparis ophylla and Zizyphus mauratiana, etc. Therefore, as it is evident, Mehsana 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.
2.8 Socio-Economic Environment
Socio-economic survey has been carried out due to personnel Questionnaire in the study area. As per
the Census of India 2011, the district has population of 13, 43,734 of which 6, 94,397 males and 6, 49,337
females. The overall sex ratio is 935 females per 1000 males. The child sex ratio (0-6 Age) is 890 girls
per 1000 boys. The district has an average literacy rate of 72.30 % with male literacy of 82.90 % and
female literacy of 61.05 %. The population density of the district is 232/sq. km.
In the study area, 68.4 per cent of the population is literate. The gender wise distribution of literates is
male 58.4 per cent and female 41.6 per cent. The overall literacy rate in the study area has been worked
out to 77.7 per cent. The male literacy rate is 89.1 per cent and female literacy rate is 65.9 per cent,
creating a gender gap in literacy rate of 23.2 per cent.
xxii
3.0 Impact Assessment
The identification and assessment of impacts over the various environmental attributes in the region due
to the proposed project activities in the proposed blocks are discussed and mitigated measures and
environmental management plan for the potential impacts have also been presented. Onshore
exploration of oil & gas is a temporary activity which lasts for about 3-4 months at each well location.
3.1 Impact on Topography and Land Use
Onshore exploration of oil & gas project is a short duration activity at each well location, typically
encompassing a period of 3-4 months from land acquisition to site abandonment. The impact would
therefore be localized, temporary and minimal. Because of the above activities, the topographical
structure may change locally. However, considering the small foot print area required during the drilling,
only marginal impact due to change in land use is anticipated.
3.2 Impact on Climate
Impact on the climatic conditions due to 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.
3.3 Impact on Air Quality
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 (including noise emission);
Emissions from possible flaring during well testing; and
Emissions from vehicles
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During the short period of site preparation mechanical shovels and earthmovers will be used for
vegetation clearance, cut and fill and other site leveling activities. These activities could generate dust
particles which can be controlled by sprinkling of water. However, these activities will be only temporary
and the impact to ambient air quality would be within the close proximity of well site.
The gaseous emissions from the DG set will be controlled by efficient combustion of fuel in the DG set.
The flaring of oil and gas during well testing is a short duration activity (about 14 - 21 days) and will be
done within a ground level enclosed pit. Wherever, required special precautions will be taken to minimize
the impact on the local environment and habitat.
3.4 Impact on Surface Water and Groundwater Quality
Drilling operations require the use of water for domestic requirements as well as for operations, but the
use will be of temporary nature and limited to a few days for each well. Hence these impacts are not
significant. The wastewater discharged from the ONGC’s drilling operations shall be collected in HDPE
lined collection pits and solar dried, so no significant impact is envisaged.The clarified wastewater will be
treated in mobile ETP located at the well sites and reutilized. The sewage will be discharged into septic
tanks and then to subsoil through soak pits.
3.5 Impact on Noise Levels
During the proposed project operation at the well sites, there would be various sources of noise in the
area, viz., drilling draw works/rotors, mud pumps, power generators, Vehicular Movement and Cranes
and material handling equipment. Acoustic enclosures would be provided to minimize the Noise impact
of DG sets. The maximum predicted noise level at about 100 m from the boundary of the well 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, the drilling operations last for only 3-4 months at each location, impact of the noise pollution due
to the proposed exploratory drilling of wells project will be insignificant on the community.
3.6 Biological Impacts
Impact on the ecology of the study area will vary with the proximity of the habitats from the each well
locations. However, the impacts are of temporary nature, which will last only for few months at each well
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location during the proposed project activities and will thus allow subsequent recovery after the activities
stops.
3.7 Demography and Socio-Economics
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 further strengthen the road
network and access to some of the remote areas with all-weather roads would be a distinct beneficial
impact. The overall impact is considered to be positive.
Impact on health due to emissions and noise from proposed project activity has been assessed to be
minimal. In addition employees working at the well site would be provided protective devices like ear
plugs/ear muffs for ensuring minimum impact on human health.
The proposed project should be possible to avoid impact on existing arable land. By following the
compensation procedures and by observing common courtesy, impacts on existing use and benefit rights
holders can be minimized.
The proposed programme is expected to generate local employment in the order of about 10-12 persons
per shift 8/12 hrs. While this benefit is small by most standards, it is a significant employment opportunity
in the block.
4.0 Environment Management Plan
The Environment Management Plan provides a delivery mechanism to address potential adverse
impacts, to instruct contractors and to introduce standards of good practices to be adopted during drilling
operations. For each stage of the programme, the EMP shall list all the requirements to ensure effective
mitigation of every potential biophysical and socio-economic impact. For each impact, or operation, which
could otherwise give rise to impact, the following information is presented:
• A comprehensive listing of the mitigation measures (actions) that ONGC shall implement
• The parameters that will be monitored to ensure effective implementation of the action
• The timing for implementation of the action to ensure that the objectives of mitigation are fully met.
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4.1 Adherence/ Compliance of Eco-Standards
ONGC adheres to various Environment Management System as per international standards. All drilling
& work over rigs are certified ISO 9001, QHSAS 18001 & ISO 14001 for Quality, Health, safety and
Environment Management system. Monitoring and management of environmental aspects being done
for a) Noise monitoring b) Condition monitoring of equipment c) Stack monitoring d) Ambient Air quality
monitoring.
4.2 Waste Water Generation
The drilling operation would generate wastewater in the form of wash water due to washing of equipment,
string and cuttings etc. The only other source of wastewater generated from drilling operation is sewage
from sanitation facilities, which shall be disposed through septic tanks/soak pits. It is expected that
wastewater in the form of washings shall be generated at an average rate of around 4 m3/day during the
drilling operations from a single well. Waste water will be discharged in HDPE lined pit, and solar dried.
4.3 Atmospheric Emissions
The combustion of diesel for power generation for the proposed project operation results in atmospheric
emissions of SO2, NOx, CO, Particulates and Hydrocarbons. Flaring during production and testing is of
14-21 days duration and atmospheric emissions are marginal.
There will be no sensitive receptors to the emissions of combustion products in the vicinity of the proposed
project 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 power generation
source to achieve fuel efficiency and therefore reduce emissions and use of low sulphur diesel oil if
available. Environmental monitoring is proposed during drilling and well testing to ensure maximum
combustion efficiency. Flaring towards any standing vegetation will be avoided. In case if it is inevitable,
a suitable barrier will be erected to prevent any vegetation scorching due to direct heat radiation; and
prior to flaring, the critical equipment will be thoroughly tested.
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4.4 Noise Environment
The modeling results show that the noise levels will attenuate to below permissible levels within the drill
site boundary. The Generators will be properly enclosed and the exhausts will be provided with silencers.
4.5 Solid and Hazardous Waste Management
The top layer of soil shall be stacked at site for reuse after completion of drilling operations. The solid
waste generated from drilling operation will be disposed in following manner.
Drill Cuttings – 150-600 MT / well will be generated, which are mainly inert solids. Drill cuttings shall be
water washed and then solar dried at site in HDPE lined pit at site. Drill cuttings are collected dried and
disposed off as per GSR 546(E) dated 30th August 2005 guidelines for disposal of solid waste, drill
cuttings and drilling fluids for Onshore drilling process. Dry cuttings shall be covered with top layer of soil.
Spent Oil – During the drilling approx. 200 lts. of spent oil shall be generated. This oil shall be sent to
authorized recyclers, as per ONGC policy.
Oil Sludge/ Hazardous waste – The proposed drilling is temporary activity and exploratory in nature, no
hazardous waste shall be generated. In case of any Oil Sludge/ Hazardous waste is generated during
the drilling activities, same shall be sent for incineration to a TSDF site.
Drilling Mud – Water base drilling mud shall be used, approx. 200m3 -600 m3 drilling mud per well is
required.
4.6 Removal of Equipment and Materials
In the event if economic quantities of hydrocarbons are found, the well will be suspended with a wellhead
in place for producing oil and gas, 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 well
site. Water supply and effluent discharge hoses and associated equipment will be removed. The access
road(s) would be reinstated.
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4.7 Decommissioning upon Abandonment
In the event that no economic quantities of hydrocarbons are found, a full abandonment plan will be
implemented for the well sites in accordance with the applicable regulations (OMR).
5.0 Environmental Mitigation
The exploratory drilling program shall be designed to avoid or minimize impacts to the environment and
local communities wherever practicable & desirable. ONGC is committed towards environment protection
with a target to achieve exploration and production goals. One of the very important part of environment
protection is the selection of location of proposed exploratory wells so that it should not affect the land
use pattern of the area, which is very important component of environment. In general locations of the
wells are decided at a safe distance from the dwellings, avoid minimum interferences with agricultural
activities, community infrastructure and also to avoid disturbances to forest lands and otherwise sensitive
or unique habitats. Wherever residual impacts remain, environment, mitigation measures shall be taken
to reduce the impact to an acceptable level or adequately offset it.
6.0 Environmental Monitoring
The following will be monitored on a regular basis throughout the life of the project to ensure a high level
of environmental performance being maintained:
• Oil content in produced water;
• Materials used in drilling fluid make up;
• Fluid losses;
• Baseline sampling prior to any drilling activity to establish pre-project environmental characteristics.
7.0 Occupational Health Surveillance Programme
This includes identification and control of health hazard and health care. Deployed Rig crew shall go for
periodic health check-up as company policy.
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8.0 Risk and Disaster Management Plan
In view of the hazardous nature of products / process handled by the ONGC, site specific Disaster
Management Plans (DMPs) are in place. These plans are based on various probable scenarios like Well
Blow Out, Fire, Explosion, Natural Calamities etc. The consequence arising out of such incidents are
accurately predicted with the help of latest technique available by various Risk Analysis Studies. To
minimize the extent of damage consequent to any disaster and restoration of normalcy is the main
purpose of DMP. There are on site Emergency Plans that deal with handling of the emergency within
boundary of the plants mainly with the help of industry’s own resources. Also when the damage extends
to the neighbouring areas, affecting local population beyond boundaries of plant, Off-site Emergency
plans is put into action in which quick response and services of many agencies are involved e.g.
Government, Fire Services, Civil defence, Medical, Police, Army, Voluntary organizations etc. EMPs are
reviewed periodically.
8.1 Objective of DMP
The following are the main objective of Disaster Management Plan:
Safeguarding lives both at installations and in neighbourhood.
Containing the incident & bringing it under control.
Minimizing damage to property & environment.
Resuscitation & treatment of causalities.
Evacuating people to safe area.
Identifying persons and to extend necessary welfare assistance to causalities.
Finally when situation is controlled, efforts are to be made to return to normal or near normal
conditions.
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9.0 Project Benefits
The proposed program will establish hydrocarbons in the block. The exploration of the oil field will result
in considerable growth of service sector and will also generate new industrial and business opportunities
in the area. The major benefits of the project include reduction of the oil import bill of the nation as well
as reduction of the imbalance in oil production and consumption. Further commercial development will
also lead to investment in Gujarat, bringing oil and gas revenues both to the State and to the Central
Government. The presence of ONGC in the region will further substantially improves the socio-economic
conditions of the region. In operation phase ONGC requires significant work force of non-technical and
technical persons. Migration of persons with better education and professional experience will result in
increase of population and literacy in the surrounding villages.
10.0 Conclusions
The proposed project has certain level of marginal impacts on the local environment. However, the
proposed project has significant beneficial impact/effects in terms of providing the employment
opportunities and various CSR practices to be followed by ONGC. Growth and development, in harmony
with the environment, has always been the approach of ONGC.
The conclusions of EIA are:
The proposed project meets the compliance requirements of various environmental
regulations;
Adoption of environmental friendly Best Management Practices results in minimising the
impacts on environment;
Community impacts of the project will be beneficial, as the project will generate significant
economic benefits for the region;
The post drilling, commercial developmental activities of ONGC can reduce the import
burdens of crude oil to the nation; and
xxx
With the effective implementation of the Environment Management Plan (EMP) during
the planning, design, construction and operation phases, the exploratory project can proceed
without significant negative impact on the environment.
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CHAPTER-1
INTRODUCTION
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1.0 Introduction
Oil and Natural Gas Corporation Limited (ONGC) is a Public Sector Undertaking (PSU) of the
Government of India, under the administrative control of the Ministry of Petroleum and Natural Gas
(MoPNG). It is India's largest oil and gas exploration and production company. It produces around 70%
of India's crude oil (equivalent to around 25% of the country's total demand) and around 60% of its natural
gas. This largest natural Oil & gas company ranks 11th among global energy majors (Platts). It is the only
public sector Indian company to feature in Fortune’s ‘Most Admired Energy Companies’ list. ONGC ranks
18th in ‘Oil and Gas operations’ and 183rd overall in Forbes Global 2000. Acclaimed for its Corporate
Governance practices, Transparency International has ranked ONGC 26th among the biggest publicly
traded global giants. It is involved in production of hydrocarbons in 26 sedimentary basins of India, and
operates over 25,500 kilometres of pipelines in the country, including sub-sea lines.
1.1 Purpose of the Report
As per Environmental Impact Assessment EIA Notification dated 14th September, 2006, onshore
exploration, development and production of oil & gas project falls under category ‘A’ of activity 1(b)
requires prior Environmental Clearance (EC) to be obtained from MoEF&CC before the commencement
of ground activity.
The application for prior EC (Form-1 and Pre-feasibility Report) for Exploration of oil and gas in 46 wells
(Onshore) of 12 ML Blocks of Western Onshore Basin has been submitted to MoEF&CC on 25th April
2018 and Terms of Reference (TOR) has been issued by MoEF&CC vide letter reference F. No. IA-J-
11011/158/2018-IA-II (I) and Proposal No. IA/GJ/IND2/74678/2018 dated 1st June 2018. A copy of the
TOR letter, along with its compliance is enclosed.
This EIA Report is prepared in line with the TOR issued by MoEF&CC and addresses the anticipated
environmental impacts of the proposed project and proposes the mitigation measures for the same for
obtaining Environmental Clearance (EC) from MoEF&CC, New Delhi. The report covers the primary data
collected during 3 months of Summer Season.
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1.2 Identification of Project and Project Proponent
1.2.1 Identification of Project
Forty Six (46) exploratory wells of 12 ML Blocks of Western Onshore Basin are proposed to be drilled to
evaluate the hydrocarbon potential lies in the Mehsana District of Gujarat state.
1.2.2 Project Proponent
Western Onshore Basin, Vadodara; is engaged in exploration activities in the Mehsana District of Gujarat
state, in Cambay Basin. The Cambay basin is a proven and rich petroleum province and has generally
favourable combination of source sediments, reservoir rocks, regional seals and traps. The Cambay
basin is the main source rock sequence in the basin along with minor contributions of oil from Kalol,
Tarapur and Olpad formation. The fluvio-deltaic sediments of the Kalol and Ankleshwar formations of
upper Eocene age are the main reservoirs. Oil trapped in these upper Eocene reservoirs are effectively
sealed by the Tarapur/Kanwa shales of upper Eocene-Oligocene age. A favourable combination of
reservoir-source-cap in the Eocene –Oligocene sequence of the basin formed essentially one petroleum
system. This can be divided into two sub systems depending on its development in the Northern and
Southern part of the basin. The Cambay shale-Kadi/Kalol Tarapur petroleum system in the northern part
of the basin (Cambay-Tarapur and Ahmedabad-Mehsana Blocks, and the Cambay shale – Hazad-Kanwa
petroleum system in the southern part of the basin (Narmada and Broach Jambusar blocks). The said
ML Blocks are with ONGC since 1965 with 100% operatorship and producing blocks. In support of the
long term hydrocarbon exploration program, ONGC proposes to drill exploratory wells in the said ML
Blocks in deeper prospects.
1.2.3 Proposed Project
As per the proposed project, Forty Six (46) of exploratory wells to be drilled in12 ML Blocks of Mehsana
District of Gujarat state, in Cambay Basin in the Oil and Natural Gas Corporation Ltd (ONGC) operated
acreages. 46 locations (Onshore) of 12 ML Blocks were considered after 2D and 3D seismic data
acquisition processing and interpretation. The targeted depths of proposed exploratory wells shall be up
to 2000-3000 mts. The said ML Blocks are with ONGC with 100% operatorship and are producing Blocks
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till date. In support of the long term hydrocarbon exploration program, ONGC proposes to drill exploratory
wells in the 12 ML Blocks in new prospects.
1.3 Brief Description of the Project
1.3.1 Nature of the Project
The proposed project intends to identify the onshore exploration of oil & gas in Forty Six (46) wells in the
Mehsana District of Gujarat state, in Cambay Basin in the Oil and Natural Gas Corporation Ltd (ONGC)
operated acreages.
1.3.2 Size of the Project
ONGC has identified onshore 46 exploratory wells of oil & gas in non–forest area of 12 ML blocks in
Mehsana district of Gujarat. The proposed project falls in a fairly well explored, productive hydrocarbon
basin of Cambay Basin. Operational areas for the 12 Blocks covered in this study having an area of
448.89 Sq Km.
1.3.3 Project Site Details
Brief description of the project is given in Table 1.1. Details of block coordinates is given in Table 1.2.The
study area map showing the block location are shown in Figure-1.1 and the topographical sheet of the
block location are given in Figure 1.2
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Figure 1.1: Index Map of the Area
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Figure 1.2 Topographic Sheets of Block Locations in Mehsana District
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Table 1.1: Brief Description of the Project
S. No. Item Details
1. Name of the Project Exploratory drilling of Forty Six (46) wells in 12 ML Blocks
of Western Onshore Basin lies in the Mehsana District of
Gujarat state.
2. Project Sector 12 ML Blocks of Western Onshore Basin
3. Location of the Project Mehsana District of Gujarat state
4. Project Region Cambay Basin of Mehsana District
5. Block Area (Sq. Km.)
Jotana ML-39.50 sq. km ;
Linch ML 43.73 sq. km ;
Linch Ext – I ML 34.25 sq. km ;
Nandasan Langnaj ML 61.90 sq. km ;
North Shobhasan Ext – I ML 56.85 sq. km ;
Jotana – Warason ML 38.05 sq. km ;
Kadi ML 64.49 sq. km ;
Linch Ext – II ML 13.35 sq. km ;
Mansa ML 58.72 sq. km ;
Jakasana ML 9.8 sq. km ;
East Shobhasan ML 22.42 sq. km ;
Balol Ext. I ML 5.83 sq. km.
6. Total Block Area of the
Project 448.89 sq. km
7. Total Cost of the Project
460 crores
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Table 1.2 Details of Block Coordinates
S.No. Block Name
Area (Sq.Km.)
Point Latitude Longitude
Deg. Min. Sec. Deg. Min. Sec.
1
Jotana -ML
( 39.50)
a 23 28 46.744 72 17 12.94
b 23 28 9.743 72 16 47.95
c 23 27 28.746 72 17 10.36
d 23 28 7.738 72 18 4.928
e 23 25 6.65 72 20 28.421
f 23 32 52.724 72 18 34.949
a 23 28 46.744 72 17 12.941
2 Linch ML
( 43.73 )
h 23 24 51.75 72 20 39.926
i 23 23 31.751 72 22 27.908
j 23 26 1.738 72 25 9.89
k 23 29 25.728 72 28 5.876
l 23 30 0 72 27 19.876
m 23 29 13.733 72 26 15.007
n 23 29 13.733 72 26 15.886
o 23 27 37.732 72 26 15.886
p 23 27 37.735 72 24 31.91
q 23 28 2.838 72 24 31.91
g 23 27 43.736 72 24 3.899
h 23 24 51.75 72 20 39.926
3 Linch Extn-I ML
( 34.25 )
r 23 24 58.748 72 18 33.736
s 23 22 37.758 72 19 13.937
t 23 22 35.562 72 19 7.54
u 23 21 42.761 72 19 38.928
v 23 20 58.765 72 19 56.917
w 23 22 1.758 72 22 18.901
x 23 23 31.751 72 22 27.908
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y 23 24 51.751 72 20 39.926
z 23 25 52.748 72 19 52.417
r 23 24 58.748 72 18 33.736
4 Nandasan -Langnaj ML
( 61.90)
A 23 29 25.728 72 28 5.876
B 23 26 1.738 72 25 9.89
C 23 24 26.748 72 23 26.902
D 23 22 57.749 72 25 6.892
E 23 23 52.746 72 27 10.89
F 23 25 16.741 72 29 42.871
G 23 26 1.734 72 29 5.878
H 23 26 13.736 72 29 57.869
A 23 29 25.728 72 28 5.876
5
North Sobhasan Extn-I ML
( 56.852 )
I 23 38 43.303 72 24 49.496
J 23 43 39.583 72 20 14.431
K 23 42 53.683 72 18 57.946
L 23 35 19.712 72 21 47.138
M 23 37 11.705 72 21 49.914
N 23 37 11.705 72 22 41.93
O 23 37 11.705 72 23 7.908
I 23 38 43.303 72 24 49.496
6 Jotana -Warosan ML
( 38.05 )
P 23 30 10.735 72 19 14.329
Q 23 28 8.339 72 19 44.342
R 23 26 37.741 72 22 46.312
S 23 27 43.736 72 24 3.899
T 23 30 1.732 72 23 20.918
U 23 30 1.732 72 22 24.924
V 23 30 33.131 72 22 15.01
W 23 30 24.329 72 21 45.925
X 23 30 1.732 72 21 51.912
Y 23 30 17.73 72 19 57.94
P 23 30 10.735 72 19 14.329
7 Kadi-ML
(64.49)
P 23 25 26.749 72 17 25.955
Q 23 24 44.057 72 16 12.353
R 23 15 39.78 72 18 51.934
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S 23 16 40.778 72 20 11.908
T 23 19 7.778 72 20 43.904
U 23 20 58.765 72 19 56.917
V 23 21 42.761 72 19 38.929
P 23 25 26.749 72 17 25.955
8 Linch Extn-II ML
( 13.35 )
P 23 28 8.339 72 19 44.342
Q 23 25 6.65 72 20 28.421
R 23 24 51.75 72 20 39.926
S 23 26 37.741 72 22 46.312
P 23 28 8.339 72 19 44.342
9 Mansa
(58.72)
A 23 35 51.698 72 34 57.853
B 23 35 48.707 72 34 3.864
C 23 33 26.708 72 33 48.838
D 23 30 6.718 72 35 0.841
E 23 30 6.721 72 33 37.85
F 23 26 9.737 72 35 13.83
G 23 26 56.728 72 37 35.814
H 23 25 21.734 72 38 57.818
P 23 25 54.732 72 40 13.807
Q 23 27 31.723 72 39 14.818
R 23 27 53.719 72 40 29.795
S 23 28 15.726 72 40 15.816
T 23 28 1.726 72 37 55.808
U 23 28 34.223 72 37 52.813
V 23 28 31.724 72 36 52.837
W 23 30 6.718 72 35 52.829
X 23 34 8.706 72 34 22.836
A 23 35 51.698 72 34 57.853
10 Jakasana
(9.8)
A 23 26 54.442 72 17 29.335
B 23 27 1.746 72 17 57.952
C 23 24 58.748 72 18 33.736
D 23 25 52.748 72 19 52.417
E 23 26 50.741 72 19 6.445
F 23 26 31.747 72 18 44.939
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G 23 26 49.744 72 18 22.943
H 23 27 16.646 72 18 44.831
I 23 28 7.738 72 18 4.928
J 23 27 28.746 72 17 10.36
A 23 26 54.442 72 17 29.335
11 East Shobhasan
(22.422)
P 23 35 40.211 72 27 37.897
Q 23 35 3.71 72 27 35.892
R 23 33 51.71 72 27 33.887
S 23 33 54.713 72 25 37.909
T 23 32 22.722 72 25 47.107
U 23 32 22.718 72 29 34.886
V 23 33 31.709 72 29 36.863
P 23 35 40.211 72 27 37.897
12 Balol Extn-I
(5.83)
a 23 38 7.71 72 12 45.983
b 23 37 9.714 72 12 37.987
c 23 37 9.714 72 14 5.982
d 23 37 11.69 72 14 18.366
e 23 37 40.714 72 14 9.964
f 23 38 49.711 72 14 9.964
a 23 38 7.71 72 12 45.983
1.3.4 Importance of the Project
India is highly dependent on import of crude oil. Net imports of crude oil is 202.85 MTs during 2015-16.
Although more than 70% of its crude oil requirements and part of the petroleum product requirement is
met from imports, India has developed sufficient processing capacity over the years to produce different
petroleum products. As result, India is now a net exporter of petroleum products. The export of petroleum
products increased to 60.53 MT during 2015-16.
Energy security has become one of the top three goals of the Indian Government. The Indian Government
is encouraging development and production of oil and gas to a great extent. This would primarily allow
India to tap its own resources there by reducing its import bill.
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Discovery of viable hydrocarbon reserves in the state can boost the state’s economic development to a
great extent. It would also catalyse influx of industries in the state. The proposed exploration project is
thus of immense significance for the Country. Extraction of hydrocarbons in these blocks will substantially
improve the socio-economic conditions of the region. The proposed project will also help to discover the
geological past to create the economic future for the region as well as to the country.
1.4 Scope of the Study
With a view to assess the environmental impacts arising due to the proposed drilling for oil & gas in 12
blocks in Mehsana district, Gujarat, ONGC being NABET accredited organization had prepared EIA
report for various environmental components including air, noise, water, land and biological components
along with parameters of human interest which may be affected and also prepared an Environmental
Management Plan (EMP) for mitigating adverse impacts.
ONGC has availed the services of M/s. ABC Techno Labs India Private Limited, Chennai to undertake
Baseline Environment Monitoring. ABC Techno Labs India Private Limited is an ISO 9001:2008,
ISO14001: 2004, OHSAS 18001:2007 certified company and accredited by National Accreditation Board
for Testing and Calibration Laboratories (NABL).
Environmental baseline monitoring has been carried out during three months representing summer
season and used to identify potential significant impacts. The scope of the present study is in-line with
the TOR as recommended by MoEF&CC. The scope of study broadly includes:
To conduct literature review and to collect data relevant to the study area;
To undertake environmental monitoring so as to establish the baseline environmental status
of the study area;
To identify various existing pollution activities in the ambient levels;
Establishing the relevant features of the proposed project that are likely to have an impact
on the environment;
Predicting the impacts on the environment due to proposed project;
To evaluate the predicted impacts on the various environmental attributes in the study area
by using scientifically developed and widely accepted environmental impact assessment
methodologies;
To prepare a Disaster Management Plan (DMP) based on Risk Assessment, studies;
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To prepare an Environment Management Plan (EMP) outlining the measures for improving
the environmental quality and scope for future proposed project activities and Occupational
Health and Safety for environmentally sustainable development; and
To identify critical environmental attributes required to be monitored.
The literature review includes identification of relevant articles from various publications, collection of data
from various Government agencies and other sources.
1.4.1 Administrative and Legislative Background
The principal Environmental Regulatory Agency in India is the Ministry of Environment and Forest and
Climate Change (MoEF&CC), New Delhi. MoEF &CC formulates environmental policies and accords
environmental clearance for the projects.
1.4.2 Study Area for EIA The study area for the EIA covers the 10 km radius from the boundaries of 12 blocks in Mehsana district. The total block area is considered as the study area.
1.4.3 Methodology of the Study
Engineers and scientist of M/s. ABC Techno Labs India Private Limited, Chennai along with ONGC officials had conducted a reconnaissance survey and sampling locations were identified on the basis of:
Collection, collation and analysis of baseline data for various environmental attributes viz Ambient air quality, Water quality, Soil, and Noise etc.
Predominant wind directions in the study area as recorded by India Meteorological Department (IMD);
Existing topography, location of surface water bodies like ponds, canals and rivers;
Location of villages/towns/sensitive areas;
Accessibility, power availability and security of monitoring equipment, pollution pockets in the area; and
Areas which represent baseline conditions.
Field studies have been conducted for a period of three months (27th April to 27th July, 2018) representing
summer season to determine existing conditions of various environmental attributes as outlined in Table-
1.3.
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TABLE-1.3 ENVIRONMENTAL ATTRIBUTES AND FREQUENCY OF MONITORING
Sr. No
Environmental Component
Sampling Locations
Sampling Parameters
Total Sampling
Period
Sampling Frequency
1 Meteorology One central location
Temperature, Wind Speed, Wind Direction, Relative Humidity, Rainfall
One non monsoon season (Three months)
Continuous hourly recording
2 Ambient Air Quality
11 Locations PM2.5, PM10, SO2, NOx, CO, VOC & BTX, THC CH4-HC and
non CH4-HC
Two consecutive days per week
24 hourly samples
3 Water Quality 14 Locations of surface water & 07 locations of Ground water
As per IS: 10500 Grab sampling Once during study period
4 Noise Monitoring 95 Locations Sound Pressure Levels
Continuously for 24 hours
Once during study period
5 Soil Analysis 08 Locations within study area
Physical and Chemical characteristics
Composite sample
Once during study period
6 Ecology Terrestrial Ecological Locations & Aquatic location within study area
Flora and fauna Field observations and secondary sources
Once in study period
7 Demography and Socio-economic aspects
Total block area Demographic profile
Based on District Census Handbook (2011) and field observations
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Sr. No
Environmental Component
Sampling Locations
Sampling Parameters
Total Sampling
Period
Sampling Frequency
8 Land Use Total block area Trend of land use
change for different
categories
Based on District Census Handbook
(2001) and satellite images
9 Geology - Geological history
Data collected from secondary
sources
10 Hydrology - Drainage area and
pattern, nature of streams, aquifer characteristics, recharge and discharge rates
Based on data collected from
secondary sources
Apart from the primary data on the existing baseline quality status of various environmental components,
a summary of physical, natural, social and cultural environment has also been provided incorporating
secondary data collected from various sources.
1.5 Contents of the Report
The report has been framed in eleven chapters and presented as follows:
Chapter-1.0: Introduction
This chapter provides background information of the project, brief description and objectives of the project,
description of the area, scope, methodology and organization of the study.
Chapter-2.0: Project Description
This chapter presents the information on the proposed project activities, technology being adopted, sources
of pollution and proposed control measures.
Chapter-3.0: Description of the Environment
This chapter presents the methodology and findings of field studies undertaken to establish the baseline
conditions.
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Chapter-4.0: Anticipated Environmental Impacts and Mitigation Measures
This chapter details the inferences drawn from the environment impact assessment of the project during
Exploration, development and production phase. It describes the overall impacts of the project and
underscores the areas of concern which need mitigation measures.
Chapter-5.0: Analysis of Alternatives
This chapter presents the analysis of alternative sites and technologies considered for the proposed
project.
Chapter-6.0: Environmental Monitoring Programme
This chapter provides recommendations for Environment Management Plan (EMP) including mitigation
measures for minimizing the negative environmental impacts of the project. Environmental monitoring
requirements for effective implementation of mitigative measures during operation of the project along
with required institutional arrangements for their implementation.
Chapter-7.0: Additional Studies
This chapter covers the details of risk involved in the project, public hearing, Disaster Management Plan
(DMP), Occupational Health and Safety (OHS) and summary of other special studies as per TOR
conditions.
Chapter-8.0: Project Benefits
This chapter presents the details of proposed Corporate Social Responsibility (CSR) activities and the
benefits of the project to the community.
Chapter-9.0: Environmental Cost Benefit Analysis
This chapter contains the Cost benefit analysis from environment point of view.
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Chapter-10.0: Environment Management Plan
This chapter contains the detailed Environment Management Plan.
1.6 Status & Stage of Regulatory Framework
As per the Schedule attached to the EIA Notification 2006, as amended till date, the proposed project is
covered under Project or Activity, 1(b), namely Offshore and Onshore Oil and Gas Exploration,
Development and Production. Such activities are also listed as Category A under the said Notification,
requiring prior Environment Clearance (EC) from the Impact Assessment Authority (IAA), i.e. the Ministry
of Environment, Forests & Climate Change (MoEF&CC), New Delhi.
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Chapter 2
Project Description
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2.0 PROJECT DESCRIPTION 2.1 Introduction
This chapter presents the project information including technical details of the proposed Exploration of oil
& gas operations, utilities and services, infrastructure facilities and sources of pollution. The expected
quantum of the waste generation and treatment and safe disposal of the waste are also discussed in the
chapter.
2.2 Type of the Project
The hydrocarbon reserve data obtained from the various wells drilled so far have shown very encouraging
results. So far more than 500 numbers of wells (including exploratory wells) have been drilled in this field.
A lot of scope still exists in exploring new sub-surface structures in this area for hydrocarbons. Hence,
ONGC has planned to drill 46 wells in 12 blocks in Mehsana district, Gujarat.
2.3 Need of the Project
The demand for petroleum has recorded a considerable increase over the year from 30 million tonnes in
1980-81 to about 115 million tonnes at present. This growing demand poses a big challenge to oil
producing companies. Proposed drilling activities will be under taken by ONGC in these blocks may lead
to in helping meet some part of the rising oil and gas requirement of the country . By drilling exploratory
well new discovery can be made for future oil demand. Also, new oil finds of the blocks will lead to
reduction in India’s dependence on imported crude oil and thereby resulting into considerable saving in
foreign exchange.
Demand-Supply Gap
Presently India is importing 75% of its required crude oil.
Export Possibility
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Nil, Indian domestic market is deficient in supply and hence all the production will be utilized locally if any
after completion of exploratory drilling phase.
Domestic / Export Markets
All produced crude oil can be refined in India and sold locally. In case of gas, it would be fed through the
pipeline within the state to local consumer.
Employment Generation (Direct and Indirect) due to the Project
Direct
~30-40 local persons will be deployed at the drilling rig for a short duration of about 60-90 days
Indirect
~8-10 persons would be engaged in providing support services to the drilling operation including
warehouse support (managing the logistics of securing and supplying the required materials for the
project).
2.4 Project Location and Project Details
ONGC has identified 46 wells for Exploratory drilling in 12 onshore ML blocks in Mehsana district, Gujarat
covering Linch, Shobhasan, Kadi and Mansa oil fields.
2.4.1 Typical Well Site Details
The site will be sized to contain all equipment and buildings, storage, workshops, etc. using distances
between various rig components in line with existing rules and regulations for the area of operation and
the approved standard operating procedures of the drilling contractor. Within the above constraints, the
site shall be sized to minimize environmental impact. The approximate area of each well site is dependent
on the type of drilling equipment deployed which in turn is dictated by the planned depth of drilling.
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Minimum land required at each well site during drilling will be 110 m x 110 m, i.e., 1.21 ha. On an average,
the land requirement at each well site, including site facilities and camp site is considered as 1.21-1.5 ha.
Each well site will require the following facilities:
Portable office cabins / rest rooms (container type cubicles);
Drilling rig foundation and celler;
Foundation / pits for ancillary equipment;
Space for drill rig equipment, working area and materials lay down area;
Waste storage pits;
Cutting disposal (impervious lined) pits;
Waste storage pit;
Septic tank with soak away pits;
Paved and contained chemical storage area;
Above ground diesel storage tanks with paved and bounded area;
Radio room;
Storm water drainage system;
Internal roads and fencing.
In the proposed project, each well sites will be restricted access area and fenced all round with round the
clock watch and ward facility. Entry of vehicles into the drilling site area will be prohibited except for
material movement. Adequate parking facilities will be provided outside the drilling location.
2.5 Size or Magnitude of Operation
The proposed drilling in 12 onshore ML blocks covering an area of 448.89 km2 to establish the presence
of hydrocarbon reserves. The estimated cost of the proposed project is approximately Rs. 460 Crores. The
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salient features of the project and magnitude of various resources required for the project is given in Table-
2.1.
TABLE-2.1 SALIENT FEATURES OF THE PROPOSED PROJECT
Sr. No. Features Details
1 Total block area in the district 12 Blocks of area 448.89 sq.km in Mehsana district, Gujarat
2 Project Operator Oil and Natural Gas Corporation Limited (ONGC)
3 Proposed number of wells 46 wells
4 Depth of wells 2000-3000 m (approximately)
5 Estimated project cost Total of Rs. 460 Crores
6 Duration of drilling 3 - 4 months for each well
7 Land requirement at each well site including site facilities and camp site
Total Average 1.5-2.25 ha At each well site: about 1.56 ha Base Camp: 0.5 ha
8 Water requirement 25 m3/day
9 Drill cuttings generation at each well site
up to 500 m3/well approximately
10 Drilling Wastewater generation at each well site
About 04 m3/day (for solar evaporation in lined pit at drilling site)
11 Domestic wastewater generation at each well site
01 m3/day ( in septic tank, followed by soak pit)
12 Power requirement for each well
1250 kVA X 2 nos & 1 nos standby
13 Manpower requirement for each well
Approx. 20 per shift of 12 hrs.
2.5.1 Resource Requirement for the Project
2.5.1.1 Land Requirement
The minimum land required at each well site during Exploration of oil & gas will be 110 m x 110 m, i.e., 1.21-1.5 ha. The land will be acquired on a temporary basis and if commercial quantity of oil or gas is found, the land will be taken on long lease and if oil and gas is not found in commercial quantities, the land will be returned to the owner by restoring the land as per restoration policy of ONGC.
2.5.1.2 Water Requirement
Water is basically required for preparing drilling mud, direct washing of drill cuttings, cooling of gas engines and for meeting domestic needs of the campsite. Typically, the water consumption for each well will be 25 m3/day. However, the drilling and domestic water requirement would depend on the time required to drill
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the well, which is primarily dependent on the proposed depth. Table-2.2 gives the water consumption for a typical each well site. Water balance diagram of each well site is given in the Figure: 2.1
TABLE-2.2 WATER REQUIREMENTS FOR EACH WELL SITE
S. No. Purpose Peak water required during Drilling period (KLD) per well
Drilling Operation
1 Mud preparation 18
2 Drill cutting washing 05
Derrick floor Washing
3 Desander 05
Desilter
4 Domestic requirement 05
5 Mud Pump / Equipment Cooling 02
Total Water requirement for Drilling (KLD) 35
Actual Requirement of fresh water (KLD) 25
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Figure 2.1: Water Balance of each well site The water requirement will be met through water tankers from nearby ONGC Installations. Suitable water transport arrangement will be made to transfer water for both drilling and domestic purposes.
2.5.1.3 Power Requirement
The power requirement of the drilling rig will be catered through 03 Nos of 1250 kVA Diesel Generator (DG) sets with 1 Nos of DG set will be kept as Stand by. The DG set details and fuel requirements is given in Table-2.3.
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TABLE-2.3 DETAILS OF DG SETS
Location DG Capacity Operational Stand by Fuel Requirement
Drilling site 1250 kVA 2 1 2.5-3.0 KLD
2.5.1.4 Manpower Requirement
The each well site construction would be done largely by employing local labor. At each well site construction, local employment will be generated for about 10 person/shift.
2.5.1.5 Drilling Mud
Only water-based drilling mud will be used for the drilling of all wells. Drilling of wells requires specially formulated muds which basically comprise inert earth materials like bentonite, barite in water with several additives to give mud weight, fluidity and filter cake characteristics while drilling. The drilling muds have several functions like lubrication and cooling of the drill bit, balancing subsurface formation, bringing out the drill cuttings from the well bore, thixotropic property to hold cuttings during non-operations, formation of thin cake to prevent liquid loss along well bore etc. Several additives are mixed into the mud system to give the required properties. Water based mud will be used to the possible extent in the drilling but use of synthetic based mud may require due to complexities associated with the geological formation and associated hole stability problems.
The constituents of water based mud (WBM) are given in Table-2.4. The special additives and their functions in WBM are shown in Table-2.5.
TABLE-2.4 CONSTITUENTS OF WATER BASED MUD (WBM)
Sr. No Chemicals
1 Barite
2 Bentonite
3 Carboxy Methyl Cellulose
4 Mud Thinner / Conditioner
5 Resinated Lignite
6 Non-Weighted Spotting Fluid
7 Weighted Spotting Fluid
8 EP Lube
9 Drilling Detergent
10 Caustic Soda
11 Potassium Chloride
12 Soda Ash
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TABLE-2.5
SPECIAL ADDITIVES AND THEIR FUNCTIONS IN WATER BASED MUD
Sr. No. Discharge Category Exploration
1 Sodium bicarbonate Eliminate excess calcium ions due to cement contamination
2 Sodium chloride Minimize borehole washout in salt zone
3 Groundnut shells, mica of cellophane Minimise loss of drilling mud to formation
4 Cellulose polymers or starch Counter thick, sticky filter cake, decrease filter loss to formation
5 Aluminium stearate Minimize foaming
6 Vegetable oil lubricant Reduce torque and drag on drill string
7 Pill of oil based mud spotting fluid Counter differential pressure sticking of string. Placed down hole opposite contact zone to free pipe.
The main components of drilling mud are slurry of inert solids suspended in a liquid phase. The main constituents of the water-based mud are Bentonite and Barites and Calcium carbonate, all of which are natural minerals. The role of the mud in pressure control is especially important. The density of the mud can be increased by the addition of barite weighting material. Bentonite and Calcium carbonate are employed to improve the theological properties and enable the drill cuttings to be transported from the hole while drilling and also be suspended in the fluid while the drill bit is being changed. The barite used in the drilling mud would be as per American Petroleum Institute (API) standard specifications.
If Synthetic Based Drilling mud (SBM) need to be used after certain depth, synthetic mud will be recycled completely and at the end of the drilling activities, drilling mud is collected and reused in subsequent drilling operations.
2.6 Proposed Schedule for the Project Approval and Implementation
The duration of various stages of the proposed project is given as under:
The duration of construction works including site excavation, preparation and well pad construction is expected to last approximately thirty days for each well site.
Well testing operation will be done over a period of 2-3 days.
Abandonment and restoration of the each well site is expected to take about one month.
Thus, on an average, site preparation and drilling of one well is likely to take approximately 3-4 months under normal conditions. Working hours during the Exploration activity will be 24 hours per day, seven days per week with 12 hours per shift.
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2.7 Technology and Process Description
The activity involves drilling of the hole across various ground layers to a predetermined depth. Drilling
operations in on land areas are generally the same irrespective of geographical area of operation. Drilling
operation is carried out using an electrically operated rig. A typical drilling rig sketch is shown in Figure-
2.2
Drilling unit for exploration of oil & gas wells consists of a derrick at the top of which is mounted a crown
block and a hoisting block with a hook. From the swivel is suspended a Kelly stem which passes through
a square or hexagonal Kelly bush which fits into the rotary table. The rotary table receives the power to
drive it from an electric motor. The electric motor rotates the rotary table, through which passes the Kelly
bush, and the rotations are transmitted to the bit as the drilling progresses, the drill pipes in singles are
added to continue the drilling process. At the end of the bit life, the drill pipes are pulled out in stands and
stacked on the derrick platform. A stand normally has 3 single drill pipes. After changing the bit, the drill
string is run back into the hole and further drilling is continued. This process continues till the target depth
is reached.
During the course of drilling, cuttings are generated due to crushing action of the bit. These cuttings are
removed by flushing the well with duplex/triplex mud pumps. The mud from the pump discharge through
the rotary hose connected to stationary part of the swivel, the drill string and bit nozzles. The mud coming
out of the bit nozzles pushes the cuttings up the hole and transports them to the surface through the
annular space between the drill string and the hole. The mud not only carries away crushed rock from
the bottom of the hole but it also cools the bit as it gets heated due to friction with formation while rotating.
The hydrostatic head of the mud helps in balancing subsurface formation pressures thereby preventing
uncontrolled flow of formation fluids into the well bore; in extreme cases this phenomenon is termed blow-
out, a rare occurrence.
At the surface, the mud coming out from well along with the cuttings falls in a trough, passes through the
solids control equipments i.e. shale shaker of 1200 GPM capacity, desander of 1200 GPM capacity,
desilter of 1200 GPM capacity and mud cleaner. These equipments remove the solids of different sizes,
which get mixed with the mud during the course of drilling. The cleaned mud flows back to the suction
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tanks to be again pumped into the well. The drilling mud/fluid circulation is thus a continuous cyclic
operation. The most suitable clay for mud preparation is bentonite, which is capable of forming highly
dispersed colloidal suspensions. Various other chemicals are also used in mud preparation as per
requirements dictated by the temperature/pressure conditions of the wells. The mud is continuously
tested for its density, viscosity, yield point, water loss, pH value etc. to ensure that the drilling operations
can be sustained without any down-hole complications.
2.7.1 Drilling of Exploratory well
To explore hydrocarbon in sub-surface, an oil well is drilled by deploying a drill rig. In the process of
exploratory drilling, drilling fluid is used to lift the cutting from the hole to the surface. Drilling fluid is
formulated by earth clay and barites. Various types of bio-degradable polymers are also added to
maintain the specific parameters of the mud. After completion of production casing the well is tested to
determine & analyze various parameters of producing fluid.
Where a hydrocarbon formation is found, initial well tests are conducted to establish flow rates of oil &
gas and formation pressure along with other reservoir parameters. These tests may then generate oil,
gas and formation water. On completion of testing, the well would be declared oil / gas producer or dry.
Exploration, of oil & gas process may encounter various hazards such as well active situation (kicks),
blowouts, H2S situation etc. They are discussed in brief as follows.
Well Kick Situation
While drilling, if the formation pressure exceeds the hydrostatic pressure exerted by the drilling
fluid, formation fluids break out in to the well bore. This is called kick. Primary means of well
control is to have sufficient over-balance, over formation pressure. For some reason if an
unexpected over-pressurized formation is encountered while drilling and if the well control
situation arises, rig is equipped with equipment to control this situation.
Blowout Situation
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1) Crown Block
2) Catline Boom and Hoist
Line
3) Drilling Line
4) Monkeyboard
5) Traveling Block
6) Top Drive
7) Derrick or Mast
8) Drill Pipe
9) Doghouse or drillers shack
10) Blowout Preventer
11) Water Tank
12) Electric Cable Tray
13) Engine Generator Sets
14) Fuel Tanks
15) Electrical Control Room
16) Mud Pump
17) Bulk Mud Components
Storage
18) Mud Pits
19) Reserve Pits
20) Mud Gas Separator
21) Shale Shakers
22) Choke Manifold
23) Pipe Ramp
24) Pipe Racks
25) Accumulator
FIGURE-2.2 DRILLING RIG SKETCH
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Uncontrolled “well control situation” eventually leads to a blowout. Blowout can cause a partial
or total destruction of drilling rig. Blowouts are often associated with hydrocarbon spill followed
by fire.
Well Control
This set of equipment is called “Blowout Preventers (BOP)”. Blowout Preventer consists of,
“Annular Preventer”, which can generally close on any size or shape of tubular in the well bore
and closes the annular space between drill string and casing. Another type of blowout preventer
is a “Ram Preventer”. Ram preventers are of two types i.e., Pipe Rams and Shear Rams. Pipe
rams also close the annulus between drill string and casing, but they have a fixed size. As such
a specific pipe rams can be closed on a specific size of pipe.
Shear rams are generally the last choice of preventer to be operated as they shear drill string
and shut off the well bore. After determining the existing formation pressure and other geological
complexities from the seismic data, appropriate BOP will be used as per standard oil field
guideline for the same.
2.7.2 Proposed Hole Size / Casing Programme
The wells will be of “Slim Hole Design”. The wells will be drilled vertically to different depths based
on the “target” depth. It is to be noted that the figures given in the table below are approximate
and subject to change as the drilling proceeds.
2.7.3 Surface Testing & Flaring
ONGC will conduct vertical flaring at all the sites, in case the presence of hydrocarbon is
encountered. A flaring stack with burner and adequate stack height will be provided.
Approximately, the duration of the test is around 2-3 days. Temporary test separators with all
control facilities for flow metering will be provided. Testing facilities will be available at drilling rig
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for separation of liquid phase and burning of all hydrocarbons during testing. The test flare boom
will be located at a distance from the drilling rig.
2.8 Details of Project Utilities
2.8.1 Site Preparation
On identification of the proposed each well site, reconnaissance survey will be done to locate suitable
land on temporary lease basis. Land clearance for site construction at each drilling site will be kept to a
minimum practicable in order to safely accommodate the facilities.
Earth moving equipment typically a bull dozer armed with a grader blade / ripper teeth and scoop bucket
will be used for the leveling / grading and excavating work. Where possible topsoil will be cleared and
stored for later reinstatement purposes by piling it along the boundary of the site. The natural contours
will be worked on to minimise off-site disposal of excavated earth. The site area (except the pit areas)
will be provided with hard-standing by providing a layered base of coarse aggregate covered with
moorum. This is done to provide sufficient load-bearing capacity to enable all construction and drilling
operations to be executed safely.
2.8.2 Approach Roads
The approach road to each well sites will need to be constructed/ upgraded to provide access for the
drilling equipment and construction machinery and material, supply vehicles, passenger vehicles etc. In
general, it is intended to make maximum use of the existing infrastructure by strengthening the roads with
the consent of the local administration and the concerned regulatory authorities. This would result in an
added advantage to the local community. In case new roads are to be made, compensation for right of
way will be provided. The choice to leave these newly constructed roads or to restore them back to
original land use condition will depend on the requirements of the local authorities.
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2.8.2.1 Installation of Facilities
Site construction would include the impermeable layer lined drilling fluid, drill cuttings, waste and water
storage pits, foundations for the drilling rig and accessories, inter-connecting drains, secure storage
provision for chemical, oil and waste oil, portable-cabins and a sewage treatment system (septic tank and
soak away pits and piping). A ground level flare pit arrangement will be made for flaring purpose.
The mobilization of the each well site involves transportation of drilling rig in modules and erected by
means of mobile cranes. The well site equipment’s are designed as modular / skid mounted type, which
facilitates quick demobilization and re-mobilisation. The installation of the well site equipment / facilities
involves about 50 trailer loads spread over 10 days. Once the site is prepared, drilling equipment, supplies
and drilling personnel will be mobilized and the drilling rig will be erected.
The salient features of the well site facilities are detailed below.
Earthwork
The each well site area will be fenced by high barbed wire. The drilling rig will be positioned
almost in the middle of this area. Typically, a depth of 1.0 or 1.5 m is excavated around the
prospecting drilling location. Excavation work shall be carried out under the permit-to-work
system and in such a manner that the collapse of sidewalls is precluded. The foundations for the
drilling rig and accessories, inter-connecting drains, secure storage provision for chemical, oil
and waste oil, porta-cabins and a sewage treatment system (septic tank and soak away pits and
piping) waste and water storage pits will also be set up. Appropriate fencing and sign boards will
be provided to prevent persons and livestock from accidentally falling into an excavation pit.
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Surface Drainage
The proposed project sites and camps will have an adequate drainage and wastewater
conveyance system so that all wastewater are contained and can be disposed as per the Gujarat
State Pollution Control Board (GPCB) discharge norms.
The drilling rig location will be connected with paved drains to the lined drilling fluid collection
pits. Surface drains will be adequately graded and maintained and kept debris free to ensure
quick disposal of their contents. Bunds will be sized so that they can contain surface runoffs for
limited period.
Fuel & Chemical Storage Area
The fuel (Diesel) will be received in bulk quantity through road tankers and stored in above
ground steel diesel tanks. The tanks will be constructed, operated and maintained as per the
requirements of the Explosive Rules and all the statutory licenses will be obtained. The tank farm
area will be provided with secondary containment of adequate capacity to impound any
accidental leaks.
Chemicals will be stored on a paved platform with kerb walls and protected against weather
through an impervious covering. Separate storages are earmarked for liquid and solid chemicals.
All the storages are identified with tags and sign boards. All required safety precautions such as
display of the MSDS, provision of fire extinguishers are followed.
Waste Oil collection, Storage & Disposal System
Waste oil of about 150-200 liters/month from pumps or other machinery will be trapped and
manually collected and stored in a paved dedicated waste oil storage area. The storage area will
be provided with paved flooring, containment bunding and covered roofing. The storage facility
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shall be designed based on the CPCB guidelines for Hazardous waste Storage. The waste oil
will be collected and handed over to GPCB and MoEF&CC authorized waste oil recyclers at the
end of the drilling campaign.
Spill Containment System
Containment systems and oil traps will be provided to trap any escape of oil before it can leave
the drilling site. All potential sources of spillage will be equipped with drainage facilities / drip
pans / spill collection kits in order to contain spills. Drains and bunds will be sized to contain
surface runoffs for limited period and any oil detected in the drains will be manually soaked using
sorbent materials.
Water & Drilling Fluid Storage Pit
The water storage pit contains the water used for preparing drilling fluid. The drilling fluid storage
pit will collect all the wastewater, which come from the drilling operations. The wastewater
present in the waste pits will be recycled and reused during drilling phase. Whereas, the residual
wastewater from the drilling operation will be collected in waste pits for solar drying. The pit will
be lined with polyethylene propylene sheet and the overlaps welded together with the edges
bought over the rim and tucked into the soil. At the end of the drilling phase, the liquid fraction
of the waste drilling fluid will be allowed to evaporate and the pit is filled with soil and capped with
compacted moorum layer.
Drill Cuttings Disposal Pit
During drilling operations, approx. 500 m3 per well drill cutting are expected to be generated from
each well depending on the type of formation and depth of drilling. Cuttings will be collected and
disposed off in an environmentally safe manner. The cuttings disposal pit will be similar in
construction to the wastewater pit. Typically the pit (will be 2 nos of 30’ x 33’ x 5’ deep, 1 nos of
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38’ x 33’ x 5’ deep and 1 nos of 23’ x 20’ x 5’ deep) will be lined with polypropylene liner. The
cuttings disposal pit will be placed within the drilling lease area to prevent the transport of waste
mud and cuttings from the drilling site to another area to prevent any spillage on the other areas.
Domestic Sewage Treatment & Disposal System
The domestic sewage generated from the each well site operations will be disposed off in a septic
tank – soak pit system. The septic tank will conform to the IS design specification. The overflow
from the septic tank will be led into series of soak pits for sub-surface disposal.
Drilling Fluid Circulation
The drilling fluids circulation system consists of several items of equipment. The mud pump takes
in mud from the mud tanks and sends it out a discharge line to a standpipe. The standpipe is a
steel pipe mounted vertically on one leg of the derrick. The mud is pumped up the standpipe into
a flexible reinforced rubber hose called the Kelly hose. The Kelly hose connected to the swivel;
goes down the Kelly, drill pipe and drill collars and exits at the bit. The mud then does a sharp
U-turn and heads back up the hole in the annulus. The annulus is the space between outside of
the drill string and the wall of the hole. Finally, the mud leaves the hole through a steel pipe called
the mud return pipe and falls over a vibrating screen like device called the shale shaker. The
mud containing cuttings is screened out of the shaker. The mud drains back into the mud tanks
and is recycled back into the well via the mud pump, while the drill cuttings which are inert
materials of shale, sand, and clay fall into the lined waste pits. Once the mud is cleaned, it is
pumped down the drill string again. The drilling fluids left over at the end of the particular well,
which can’t be further reused, will be discharged into the lined waste pits and dried. The pits will
be provided with HDPE liners to maintain integrity and prevent any leakage. The drill cuttings
cut by the drill bit are removed from the mud by the shale shakers and other solids removal
equipment and transferred to the waste pits. The drilling fluid circulating system at rig is
essentially a self contained, closed system, shown in Figure-2.3
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Role of Drilling Fluids
Drilling fluid serves the following essential functions:
The removal of drilled solids (i.e. cuttings) from the bottom of the hole and their transport to
the surface for separation from the mud;
Lubrication and cooling of the drill bit and string;
Deposition of an impermeable cake on the well bore wall to seal the formation being drilled;
Suspension of drilling cuttings in the fluid during the interruption of drilling; and
Countering the natural formation pressures and preventing uncontrolled flow of fluid from the
formations.
The role of the drilling fluids in pressure control is especially important. If the drill bit penetrates
a formation containing oil, gas or water under pressure these fluids are prevented from flowing
into the borehole by ensuring that the drilling mud is of sufficient density to counter the natural
formation pressures. The density of the mud can be increased by the addition of barite weighting
material. Bentonite is employed to improve the rheological properties and enable the drill cuttings
to be transported from the hole while drilling and also be suspended in the fluid while the drill bit
is being changed. The barite used in the drilling mud would be as per API standard specifications.
Water based drilling fluids, which are of an environmentally acceptable nature with regards to
current Indian legislation, will be used. The water based drilling fluid will be non-hazardous in
nature.
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FIGURE-2.3 DRILLING FLUID CIRCULATION SYSTEM AT TYPICAL RIG
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2.9 Post Drilling Operations - Abandonment and Restoration
2.9.1 Demobilization & Decommissioning
Well Capping - Removal of Equipment and Materials
In the event that economic quantities of hydrocarbons are found, the well will be suspended with
a wellhead/X-mass tree 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 either left behind or reinstated based on the needs of
the local authorities.
Restoration of Cutting Containment Area
At the conclusion of well testing at each drilling site, the spent drilling fluids will be dewatered by
flocculating the contents and allowing the water phase to evaporate away. All solids & liner will
be buried in a secured lined pit and covered with soil and left onsite. The cutting mud is inert and
with appropriate lining of the pit in place it does not pose any potential for soil or groundwater
contamination. ONGC will follow a well laid site restoration plan. Tree plantation will be done on
the closed pits to restore the original soil conditions. At all the sites the pits are filled with the
black cotton soils or red soils which is available at shortest distance. Filling and plantations are
handed over to the contractors with close watch of ONGC officials.
2.9.2 Restoration of Well Sites
Decommissioning upon Abandonment
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In the event that economic quantities of hydrocarbons are found, the well site will be closed as
detailed above. In the event that no economic quantities of hydrocarbons are found, a full
abandonment plan will be implemented for the drilling sites.
The actions outlined above would apply to decommissioning upon abandonment as well, but
abandonment would be more permanent. All concrete or steel installations would be removed to
at least 1 m below ground level so as to ensure that there are no protruding surface structures.
In the unlikely event that soil is found contaminated, measures would be taken to remove or treat
appropriately all contaminated topsoil to promote its remediation. This is as per the ONGC’s
Restoration SOP.
The overriding principle being that the environment should, with time, be reinstated to broadly its
original condition. Until such time as this is achieved, ONGC would actively manage the
reinstatement process.
2.9.3 Traffic Volumes
During the civil operations earth moving equipment will be working on the access road and the
well location. It is anticipated that there will be an average of 5 truck movements a day to cater
the site preparation for an average period of about 20 days.
Prior to and after the drilling operation, when building the rig or rig move, up to 80 heavy
truckloads over a period of 4-5 days are envisaged.
During the drilling operation, supply truck movements are estimated on an average of eight to
five per day. Small vehicles movements are used mainly for transport of personnel, visitors etc.
which might be as much as 10 per day.
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ONGC will engage in constructing compacted approach roads without black topping to all well
locations and camp sites. Though this will not cause any changes in topography, the dust
generation will be less than any other village roads. The same roads can be used by the villagers
after completion of the Exploration activities.
2.10 Sources of Pollution
2.10.1 General
The various types of pollution from the proposed project operations are:
Water Pollution;
Air Emission;
Solid Waste Generation & disposal ; and
Noise Generation.
Exhaust gases from DG sets, wastewater, drilling wastes and noise from the drilling operations
are the major sources of the pollutants generated during the proposed drilling operations which
is temporary activity lasting for maximum of 3-4 months at each of the well locations.
2.10.2 Wastewater Generation and Disposal
The water will be required during the drilling rig is mainly meant for drilling mud preparation and
for domestic purposes. Thus, wastewater during this phase will comprise of drilling wastewater
and domestic wastewater.
The proposed project sites and camps site will have an adequate drainage system so that all
wastewater are contained and disposed as per the CPCB Standards. Means will be provided to
trap any escape of oil before it can leave the site. Surface drains will be adequately graded and
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kept debris free to ensure quick disposal of their contents. Minor quantity of wastewater would
be generated from cleaning operations carried out at the rig. About 5 m3/day of wastewater is
expected.
All wastewater streams except sewage will be directed to a 1.5 mm HDPE lined pit. Wastewater
collected in the pit will be solar dried.
Domestic Wastewater
Sewage generated from the camps would be discharged and treated in septic tanks. The
supernatant from the septic tanks will be passed through soak pits into the ground.
2.10.3 Air Emissions
During Exploration of oil & gas, air pollutants are emitted by the diesel engines that power the
drilling equipment. These engines release particulate matter that can contain heavy metals,
volatile organic compounds and polycyclic organic matter. They also emit sulphur dioxide, oxides
of nitrogen which contributes to smog formation. The vehicular movement associated with the
drilling activities is also an important cause for the dust pollution.
The predominant air emissions from the proposed project operations are gaseous emissions,
viz., sulphur dioxide, oxides of nitrogen and hydrocarbons.
Each power generator will have the adequate stack height for easy dispersion of gaseous
emissions. The height of the DG exhaust stack will be about 6.8 m (including the height of the
trailer from the ground).
Traces of Natural gas will be flared during the well testing phase for short period. The test flaring
will result in temporary emissions of CO2, water vapours, NOX and other trace gases in case of
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natural gas flaring and additionally particulates in case crude oil is flared. It is assumed that the
occurrence of SO2 in the flare gas would be in traces or negligible.
2.10.4 Solid Waste
The proposed project operations generate drill cuttings. The minor wastes include sanitary waste,
domestic waste and waste oil from lubricating system.
2.10.4.1 Drilling Mud
The drilling mud will be re-circulated and reused to maximum possible extent through its mud
recycling system. Maximum amount of drilling mud attached to the drill cutting is separated by
Solid control System such as Shale Shaker, clay shaker and will be recycled during the drilling
process. However, only a portion of the non-usable mud at the end of the drilling would be
discharged. The drilling mud will be collected in lined pit and solar evaporated.
2.10.4.2 Drill Cuttings
Drilling cuttings are worn out rocks from subsurface formations that are generated during drilling
operations. The drill cuttings are conveyed to the surface, suspended in the drilling fluid (drilling
mud). The drill cuttings are separated in the shale shaker from the drilling mud and are stored in
an impervious 1.5 mm HDPE lined pit. The particle size varies from coarse particles of less than
1mm diameter to few centimeters. Drill cuttings are encapsulated by a thin layer of adhering mud.
The drill cuttings will be washed thoroughly and the wastewater generated will be collected in
HDPE Lined pit at site and will be solar dried.
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2.10.4.3 Waste Pit Details
Typical sectional view of the drill cutting and drilling mud collection pit is presented in Figure-2.4
2.10.4.4 Used / Spent Oil
Used / spent lubricating oil from pumps or other machinery would be trapped and manually
collected and stored in a paved dedicated waste oil storage area. Approximately 150-200
liters/month of used/ spent oil would be generated from a drilling operation. Stored waste oil
would be disposed off to CPCB & MoEF registered used / spent oil recyclers.
2.10.4.5. Drilling Mud and Drill Cuttings Analysis
The drill cuttings & the drilling mud at each location will be tested to ensure it meets the
requirement of MoEF&CC guidelines for disposal of drill cuttings and drilling fluids for onshore
operations. The analysis carried out on spent drilling mud / cuttings during the previous drilling
campaigns by ONGC in other parts of the country have reported LC50 in excess of 30,000 mg/l.
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FIGURE-2.4 TYPICAL SECTION VIEW OF DRILLING CUT AND DRILL MUD COLLECTION PIT
2.10.5 Noise Levels
The major noise generating sources are DG sets, pumps at drilling rig and other equipment of drilling rig
would contribute to continuous noise. Typically, the noise generating sources for the 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)
Noise is not considered to be a potential threat since the drilling sites will be selected keeping in view that
there are no settlements in close proximity to the drilling site.
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2.11 Qualifications, Skills and Training Practice
a) Qualification
Jobs requiring specific qualifications and certificates e.g. welding, driving of vehicles, electrical
work, crane operation, fork lift & bulldozers operation should be carried out only by persons
having the required qualifications and certificates. The certificates should be properly checked
for adequacy and a copy of the same should be available for verification by ONGC personnel.
b) Skills
Certain jobs e.g. operation of cranes and other mechanical equipment, erection of scaffolding
need required skills and persons deployed should be checked for possession of adequate skills
and experience in carrying out such work.
c) Training
All required HSE related training e.g. safe evacuation during emergencies, permit to work
requirements, proper use of personal protective equipment, should be provided by the contractor
HSE supervisor. The training contents should be discussed with the ONGC HSE personnel.
d) Personal Protective Equipment (PPE)
No personnel will be allowed into the well site if the required PPE is not used. Adequate stock of
required PPE will be available and distributed whenever needed. The PPE requirements are hard
hat and safety shoe and those working in the drilling rig, overalls, gloves, safety glasses, nose
masks when needed) and ear-muffs. Personnel working at height (during maintenance / erection)
will need to use safety belts securely anchored.
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e) General HSE Requirements
The general HSE requirements of ONGC which is strictly complied with by all ONGC and contract
employees are enumerated below.
f) Vehicle Movement
The speed limit for vehicles is 10 kms/hr in village area and near to schools and in construction
area. On tar road maximum speed is restricted to 35 km/hr and on highway speed should not be
more then 60 km/hr for heavy vehicles and 80 km/hr for light vehicle
g) No Smoking Regulations
Smoking is strictly prohibited in all the areas in the site
h) First Aid Center
A first aid center shall be located at the construction site. The service of a doctor shall also be
available all the time in the first aid center.
i) Permits
Type of permits agreed should be obtained wherever required. Conditions and precautions
mentioned in the permit should be strictly followed.
j) Fire Extinguishers
Temporary fire extinguishers shall be readily available at convenient locations for use during any
fire emergencies.
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All persons working in the contract should be above 18 years of age and no child labour will be
engaged in any job at any time.
k) Safety Seat Belts
All the vehicles used for construction purpose should be provided with safety seat belts. No
vehicles are allowed inside the site without safety seat belts.
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Chapter 3
Description of Environment
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3.0 Introduction
This chapter illustrates the description of the existing environmental status of the study area with
reference to the prominent environment attributes to assess environmental impacts from the proposed
project activity.
3.1 Baseline environmental Study
The study area was determined through collection of samples followed by quantifying environmental
indicators of air, noise, water, land, ecology and socio-economic status. The baseline environmental
quality has been determined for Summer Season by following guidelines prescribed in MoEF & CC, EIA
notification and ToR issued to the ONGC.
The baseline environmental qualities for the proposed exploratory drilling locations have been assessed
for the following environmental components, which are most likely to be influenced by the drilling activity:
Geology
Hydrogeology
Seismicity
Land Environment
Ambient Air Quality
Meteorological conditions
Noise levels
Water quality (Surface +Ground water)
Soil quality
Biological and
Socio-economic studies.
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The primary baseline environmental quality for the EIA is assessed through field studies within the impact
zone for various components of the environment, viz. air, noise, water, Soil and socio-economic.
3.2 Geology
The Cambay basin is a proven and rich petroleum province and has generally favourable combination of
source sediments, reservoir rocks, regional seals and traps. The Cambay shale is the main source rock
sequence in the basin along with minor contributions of oil from Kalol, Tarapur and Olpad formation. The
fluvio-deltaic sediments of the Kalol and Ankleshwar formations of upper Eocene age are the main
reservoirs. Oil trapped in these upper Eocene reservoirs are effectively sealed by the Tarapur/Kanwa
shales of upper Eocene-Oligocene age.
A favourable combination of reservoir-source-cap in the Eocene –Oligocene sequence of the basin
formed essentially one petroleum system. This can be divided into two sub systems depending on its
development in the Northern and Southern part of the basin.
1. The Cambay shale-Kadi/Kalol Tarapur petroleum system in the northern part of the basin
(Cambay-Tarapur and Ahmedabad-Mehsana Blocks, and
2. The Cambay shale – Hazad-Kanwa petroleum system in the southern part of the basin (Narmada
and Bharuch Jambusar blocks).
3.3 Hydrogeology
The hydrogeological studies were carried out to understand the local geology, geomorphic features,
drainage network, aquifer characteristics and yield of water along with various components controlling
the hydrogeological regime. Hydrogeology maps of Mehsana district of Gujarat is given in Figure-3.1.
Precambrian hard rocks, semi-consolidated Mesozoic and tertiary formations and unconsolidated
quaternary alluvial deposits form multi-layer aquifer system in the district. Groundwater occurs both under
phreatic and confined conditions, however its development is restricted depending upon the aquifer
geometry and yield characteristic of individual aquifer and/or ground water quality of the formation water.
Occurrence of groundwater can be divided in two groups.
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Figure-3.1 Hydrogeology Map of Mehsana District Of Gujarat
a) Ground water in fissured formation (Hard rock): The north-eastern part of the district mainly in
Satlasna taluka is occupied by meta sediments and Post Delhi intrusives. The occurrence and movement
of ground water is governed by secondary porosity i.e. thickness and extent of weathering and size&
interconnections of fractures/joints. These formations generally don’t form good aquifer system. The
depth of dugwells range from 15-30 mbgl and of borewells from 100-120 mbgl. Depth to water level in
the dug wells varies from 5 -14mbgl and in borewells from 15to 60 mbgl. The yield of wells range from
30-120m3 /day with an average of 75m3 /day.
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b) Groundwater in porous formations (Sedimentaries): Major part of the district is underlain by post
Miocene alluvium and older sedimentary formations. These sediments are mainly consisted by Coarse
sand, gravel, kankar, silt, clay and clay stones. Groundwater occurs both under phreatic and confined
conditions in arenaceous horizons within sedimentaries. The occurrence and movement of groundwater
is mainly controlled by intergranular pore spaces.
3.3.1 Ground Water Resources
The main source of ground water recharge is by the rainfall by direct percolation to the zone of saturation.
A significant part of the rainfall is lost as runoff from area while a limited percentage of rainfall therefore
reaches zone of saturation and becomes the part of ground water storage after meeting the evaporation
and evapo-transpiration losses. There is also ground water recharge from the return flow of irrigation
water from dug wells and tube wells operated by the cultivators and from canals.
The ground water levels measured in the study area during the primary survey:-
i) Major water bearing formations: Groundwater occurs in unconfined to confined condition
in Quaternary alluvium and under unconfined condition in granite gneiss in limited area.
ii) Pre-monsoon water level: 2.15 to 34.35 mbgl.
iii) Post-monsoon water level: 1.10 to 33.77 mbgl.
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Fig 3.2: Ground water Pre Monsoon level map of Mehsana District
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Fig 3.3: Ground water Post Monsoon level map of Mehsana District
3.4 Seismicity and Floods:
Study Area is categorized in the seismic zone III, which is classified as having a fairly high probability of
earthquake shocks measuring 5 or 6 on the Richter scale, low probability of shocks of 6 or 7 on the
Richter scale and Seismic Zone IV which is referred as High damage risk Zone.
Source: Seismic Map of Gujarat from Institute of Seismological Research (Government of
Gujarat.http://www.isr.gujarat.gov.in/Seismic_Zoning_Gujarat.shtm)
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Figure-3.4 Seismic Zone Map of India
Fig 3.5 : Seismic Zone III of the Study area
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3.5 Land Environment
3.5.1 Topography:
The terrain of the district is almost flat plain except a small hilly portion in the eastern part with an elevation
ranging from 57 m to 370 m above MSL. The general slope of this district is from NE to SW. The mining
lease falls in central, SW and southern part of the district which has almost flat terrain.
3.5.2 Land Use Studies
Studies on land use aspects of eco-system play important roles for identifying sensitive issues, if any,
and taking appropriate actions for maintaining the ecological balance in the development of the region.
The objectives of land use studies are:
To determine the present land use pattern;
To analyze the impacts on land use due to proposed project activities in the study area; and
To give recommendations for optimizing the future land use pattern vis-a-vis growth of
proposed project activities in the study area and its associated impacts.
3.5.2.1 Methodology
The land use/land cover maps of the study area were obtained from Bhuvan outreach portal of National
Remote Sensing Centre, ISRO. These Land Use Land Cover maps were developed from LULC Vector
data of 2005-06, Multi-temporal satellite data of 2011-12 from Resourcesat-2 LISS III in the scale of
1;50,000. The various steps involved in the study are preparatory field work, field survey and post field
work. The Land Use Land Cover maps were prepared based on the classification system of National
standards. The land use pattern of the Mehsana District is shown in Figure 3.6 The main interpreted land
use/land cover classes of the Mehsana District and their respective areas are given in Table 3.1.
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Figure 3.6: Land Use pattern of Mehsana District.
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Table: 3.1 Land use classification and area of Mehsana District
S.NO Level – 1 Level - 2 Area
(Sq.Km)
Area
(Hectare)
1 Built-up Built-up, Urban 39.7 3970
Built-up, Mining 0.56 56
Built-up, Rural 49.44 4944
2 Agriculture
Agriculture, Plantation 1.98 198
Agriculture, Crop land 2840.89 284089
Agriculture, Fallow 117.26 11726
3 Forest Forest, Deciduous 52.19 5219
Forest, Scrub Forest 4.83 482
4 Wastelands
Barren/unculturable/Wastelands,
Gullied/Ravinous Land
42.1 4210
Barren/unculturable/Wastelands, Sandy
area
0.05 5
Barren/unculturable/Wastelands, Scrub
land
109.82 10982
5
Water bodies
Wetlands/Water Bodies,
River/Stream/canals
58.01 5801
Wetlands/Water Bodies, Coastal Wetland 5.45 545
Wetlands/Water Bodies,
Reservoir/Lakes/Ponds
20.73 2073
TOTAL 3343.00 334300
The above table indicates that, the 84.98 % of land comprises of Agriculture, Crop Land ( 284089 hectare
), 3.51 % is Agriculture, fallow ( 11726 hectare ), 3.29 % is scrub land (10928 hectare), followed by water
bodies (8419 hectare), built up land (8970 hectare) and water bodies (5701 hectare)
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3.6 Meteorology
The meteorological data recorded during the study period is very useful for proper interpretation of the
baseline information as well as for input to prediction models for air quality dispersion.
On site monitoring was undertaken for various meteorological parameters in order to generate the site
specific data. The central monitoring station (CMS), equipped with continuous monitoring equipment to
record wind speed, wind direction, temperature, humidity and rain fall was set up at the top of the building
at a height of ~ 5.0m above the ground level. The methodology adopted for monitoring surface
observations was as per the Standard norms laid down by the Bureau of Indian Standards (IS:
8829:1978) and IMD.
3.6.1 Meteorological data recorded at study area
The meteorological parameters was recorded at Rupal on hourly basis during the study period from the
date 27th April 2018 to 27th July 2018 consist of parameters like Wind speed, Wind direction, Humidity
Temperature and total rainfall. The maximum and minimum values for Temperature & Humidity are
presented in Table 3.2.
TABLE – 3.2: Summary of the Meteorological Data Generated In Study Area
Month
Rupal
Temp. (0C) Relative Humidity (%) Rainfall (mm)
Max Min Max Min
April 2018(27th to 30th) 40.1 28.2 60 34 0
May 2018 40.3 28.9 62 30 0
June 2018 37.4 27.4 87 45 30
July 2018(1st to 27th) 35.5 25.4 94 63 60
27th April 2018 to 27th July
2018 40.3 25.4 94 30 90
Source: ABC Techno Labs India Private Limited
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The summary of the wind pattern for the study period is listed in Table-3.3. The graphical presentation
of the same illustrated from Figure-3.7 (a) to 3.7 (b).
TABLE – 3.3: Summary of Wind Pattern at Rupal
Month First Predominant
Wind Direction Second Predominant Wind
Direction Average Wind Speed
(m/s)
April 2018(27th to 30th) NW W 1.3
May 2018 NW W 1.0
June 2018 NW SW 1.2
July 2018(1st to 27th) NW W 1.1
27th April 2018 to 27th July
2018 NW W 1.1
Figure: 3.7 (a): Windrose Diagram for April-18, May -18, June 18 & July 18 at Rupal
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Figure: 3.7(b): Windrose Diagram from April 27TH -2018 to July 27th 2018 at Rupal
3.6.2 Secondary Data from Indian Meteorological Dept., (IMD), Ahmedabad
The nearby India Meteorological Department station that is generating meteorological data nearest to the
study area is IMD, Ahmedabad. Hence, secondary information on meteorological conditions has been
collected from Ahmedabad IMD station. Indian Meteorological Department at Ahmedabad regularly
monitors wind direction, wind speed, relative humidity, temperature and rainfall at 08.30 hours and 17.30
hours every day. Wind rose diagrams (1971-2000) collected for IMD, Ahmedabad is shown in Figure –
3.8(a) & 3.8(b).
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Figure 3.8(a): Windrose diagrams for the month of April, May, June & July - IMD, Ahmedabad
(1971-2000)
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Figure 3.8(b): Annual Windrose diagrams from IMD, Ahmedabad (1971-2000)
The month wise mean maximum & minimum values of temperature, relative humidity and rainfall data
collected from IMD, Ahmedabad for the period 1971-2000 are presented in below Table – 3.4.
Table 3.4: WEATHER DATA FROM IMD, AHMEDABAD (1971-2000)
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max- Temp (C)
28.1 30.5 35.7 39.7 41.6 38.7 33.5 32.0 33.8 35.7 32.8 29.4
Min Temp (c)
12.0 14.0 19.1 23.7 26.5 27.3 25.7 24.9 24.3 21.3 16.6 13.2
RH (%) 49 42 35 39 45 60 77 79 71 54 47 49
Rainfall (mm)
1.9 1 0.5 2.7 10.2 95 281 234 96 12 4 0.8
Source: IMD, Ahmedabad
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Figure 3.9: Monthly Average Maximum and Minimum Temperature in ◦C
Figure 3.10: Monthly Average Rainfall in mm and Relative humidity in %
0
5
10
15
20
25
30
35
40
45
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Tem
p°C
Month
Temperature Max- Temp (C)
Min- Temp (C)
0
50
100
150
200
250
300
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Rai
nfa
ll (m
m)
Month
Rainfall and Relative Humidity RH (%)
Rainfall (mm)
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3.7 Ambient Air Quality
A reconnaissance survey was undertaken to identify the sampling locations to establish baseline status
of Ambient Air quality in the study area. The sampling stations were selected based on guidelines of air
monitoring network siting criteria such as:
Topography of the study area
Persistence of wind direction and speed
Representation of regional background
Populated and sensitive areas
Location of industries and their emission magnitude
Screening of maximum ground level concentrations and distances of their likely occurrences as
per climatological normal
Representation of valid cross-sectional distribution in down-wind direction.
3.7.1 Selection of Sampling Locations
The ambient air quality around the location within 10 km radius was monitored at eleven (11) stations. To
establish the baseline monitoring of air quality in the study area during summer season; Ambient Air
Quality Monitoring stations eleven (11) were selected using network design criteria and monitored as per
CPCB guidelines.
As per NAAQS (2009) the pollutants viz., particulate matters (PM10 and PM2.5), sulphur dioxide (SO2),
nitrogen dioxide (NO2), carbon monoxide (CO) and ammonia (NH3) were stipulated parameters for air
quality monitoring. All the parameters were monitored on 24 hourly while CO was monitored on hourly
basis. Standard analytical procedures were used for analysis and quantification of air quality parameters
and the details are given in Table 3.5 &3.6. The photographs show in sampling stations/locations are
given in the Figure 3.11.
3.7.2 Frequency and Parameters for Sampling
Ambient air quality monitoring was carried out at a frequency of two days per week at each location for
continuous three months. The baseline data of air environment was generated for the parameters namely
Particulate Matter size less than 10 µm (PM10), Particulate Matter size less than 2.5 µm (PM2.5), Sulphur
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dioxide (SO2), Oxides of Nitrogen (NOx), Carbon Monoxide (CO), Volatile Organic Compounds (VOCs),
Hydrocarbon (Methane& Non-Methane) and Hydrogen Sulphide (H2S).
3.7.3 Instruments used for Sampling
Respirable Dust Samplers APM 460 BL of Envirotech, Fine Particulate Samplers APM 550 of Envirotech
& Combo PM10 & PM 2.5 sampler AAS 271 of Envirotech were used for monitoring the Particulate matter
PM10 & PM 2.5. The Gaseous pollutant samplers AAS 109 of Ecotech or APM 411 along with APM 460
Envirotech were used for sampling of gaseous parameters like SO2, NOx, H2S, VOCs & HC. Carbon
Monoxide was measured using electro chemical sensor method. The instruments used for monitoring are
periodically calibrated every year or after in case of any repair.
3.7.4 Sampling and Analytical Techniques
The sampling and analytical techniques used for the monitoring of Ambient Air quality is given in Table
3.5. The power supply for the operation of AAQ instruments were utilized from either residential or
commercial buildings nearest to each AAQ station.
TABLE – 3.5: Techniques used for Ambient Air Quality Monitoring
S.No Parameter Technique Technical Protocol Detectable
Limit
1 Particulate Matter of size
less than 10 µm (PM10)
Gravimetric method IS 5182 Pt.23 : 2006
(Reaff. 2017) 5 g/m3
2 Particulate Matter of size
less than 2.5 µm (PM2.5)
Gravimetric method EPA- 40 Appendix L
To CFR PART 50 5 g/m3
3 Sulphur dioxide (SO2) Improved West and Gaeke IS 5182: Part 2:2001
(Reaff. 2017) 5 g/m3
4 Oxides of Nitrogen (NOx) Modified Jacob &
Hochheiser
IS 5182: Part 6:2006
(Reaff. 2017) 5 g/m3
5 Carbon monoxide (CO) Non Dispersive Infra Red
(NDIR) Spectroscopy
IS 5182:Part 10 :1999
(Reaff. 2014) 0.1 mg/m3
6 Hydrogen Sulphide (H2S) Colorimetry Method IS 5182: Part 7:1973
(Reaff.2014) 5 µg/m3
7 VOCs & BTX GC-MS/MS ABCTL/INS/SOP/035 1 µg/m3
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8 Methane HC GC FID ABCTL/INS/SOP/038 0.1 µg/m3
9 Non-Methane HC GC FID ABCTL/INS/SOP/038 0.1 µg/m3
Ambient Air Quality Monitoring (AAQM) stations were set up at eleven (11) locations with due consideration
to the above mentioned points. The Ambient Air Quality monitoring locations are given in the Table-3.6.
Monitoring Photographs enclosed as Annexure II.
TABLE – 3.6: DETAILS OF AMBIENT AIR QUALITY MONITORING LOCATIONS
Code Location Coordinates Description of AAQ Station
AAQ1 Bilodra
23o31’24.99” N 72o38’59.62” E
Rural Settlement, Top of Bilodra Panchyat Office
AAQ2 Ajol
23o30’32.26” N 72o41’16.2” E
Rural Settlement, Top of Ajol Panchyat Office
AAQ3 Ridrol
23o27’32.55” N 72o40’31.41” E
Rural Settlement, Top of Ridrol Panchyat Office
AAQ4 Fatepura
23o55’56.22” N 72o38’12.9” E
Rural Settlement, Near Fatepura Primary School
AAQ5 Kherva
23o32’37.03” N 72o26’38.79” E
Rural Settlement, Top of Kherva Panchyat Office
AAQ6 Lagnaj 23o26’53.30” N 72o29’50.84”E
Rural Settlement, Top of Residential building
AAQ7 Irana 23o18’30.43” N
72o23’18.9” E Rural Settlement, Near Ram
Pir Temple
AAQ8 Rupal 23o41’4.63” N 72o20’36.18” E
Rural Settlement, Top of Milk Dairy
AAQ9 Ambaliyasan 23o27’9.35” N 72o25’26.66” E
Rural Settlement, Top of Residential building
AAQ10 Linch 23o29’44.95” N 72o22’27.84” E
Rural Settlement, Top of Linch Panchyat Office
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AAQ11 Sunsar 23o38’47.27” N 72o13’42.98” E
Rural Settlement, Top of Sunsar Panchyat Office
The study area map covering the Ambient Air Quality Monitoring station is depicted in Figure – 3.
Figure – 3.11 Map Showing AAQ monitoring Stations
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AAQ1 BILODRA AAQ2 AJOL
AAQ4 FATEPURA AAQ5 KHERVA
AAQ7 IRANA AAQ8 RUPAL
Fig3.12: Ambient Air monitoring Locations of the Study Area
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3.7.5 Ambient Air Quality Results
Ambient air quality results of PM10, PM2.5, Sulphur Dioxide, Oxides of Nitrogen, Carbon Monoxide,
Methane and Non-Methane Hydrocarbon are given in Annexure-1. Hydrogen Sulphide, Volatile Organic
Compounds and BTX (Benzene, Toluene and Xylene) was not observed in the study Area.
3.7.6. Summary of Ambient Air Quality Result
Summary of ambient air quality results of PM10, PM2.5, Sulphur Dioxide, Oxides of nitrogen, Carbon
monoxide, Methane and Non-Methane Hydrocarbon are summarized in Table 3.7. Volatile Organic
Compounds, BTX (Benzene, Toluene and Xylene), Methane and Non Methane Hydrocarbons were not
reported in study Area.
TABLE-3.7: Summary of Ambient Air Quality Monitoring Results
AAQ Location
PM10 µg/m3 PM2.5 µg/m3 SO2 µg/m3
Min Max Mean 98%le Min Max Mean 98%le Min Max Mean 98%le
AAQ-1 52 75.4 63.9 73.5 20.1 45.1 28.4 42.9 5.9 9.8 6.9 9.3
AAQ-2 49.8 70.5 62.1 70.1 18.6 31.6 24.1 31.1 5.9 11.2 8.1 11.1
AAQ-3 50.1 69.4 61.5 68.9 21.5 29.4 25.1 29.3 5.2 6.8 5.8 6.8
AAQ-4 41.2 62.3 54.5 62.0 21.3 35.4 27.0 33.7 5.2 7.7 6.5 7.7
AAQ-5 52.1 80.4 65.6 76.4 19.8 38.9 27.8 35.7 5.1 7.4 5.8 7.0
AAQ-6 45.9 67.8 58.6 67.0 21.7 29.5 24.5 28.5 5.3 6.8 6.0 6.8
AAQ-7 54.8 70.5 62.2 68.8 21.9 30.8 26.0 30.2 5.1 7.9 6.4 7.7
AAQ-8 51.9 69.3 60.6 67.8 19.8 31.8 24.3 31.1 5.1 6.4 5.8 6.4
AAQ-9 41.3 57.8 50.2 57.5 22.3 31.4 27.1 31.3 5.1 6.9 5.8 6.8
AAQ-10 41.2 60.4 53.9 60.3 22.3 35.4 25.1 32.8 5.3 10.8 6.4 10.1
AAQ-11 52.5 69.9 61.4 69.4 23.1 33.1 27.7 33.0 6.4 14.1 9.9 13.8
NAAQ Standards
100 60 80
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: Source: ABC Techno Labs India Private Limited
The data collected was subjected to statistical analysis like minimum, maximum, average and standard
deviation. The observed ambient air quality data within the study area from the project site is reported
described briefly:
3.7.7 Observations
PM10: The maximum and minimum concentrations for PM10 were recorded as
80.4 g/m3 and 41.2 g/m3 respectively. The maximum concentration was recorded at the Kherva and the
minimum concentration was recorded at Linch. The average concentrations were ranged between
50.2g/m3 – 65.6 g/m3 as shown in figure 3.13.
AAQ Location
NOx µg/m3 CO mg/m3
Min Max Mean 98%le Min Max Mean 98%le
AAQ-1 10.1 24.6 16.7 23.7 0.21 0.39 0.28 0.38
AAQ-2 10.9 19.6 16.5 19.5 0.11 0.19 0.15 0.19
AAQ-3 9.6 13.9 11.5 13.7 0.11 0.19 0.15 0.18
AAQ-4 10.1 12.8 11.3 12.8 0.11 0.19 0.15 0.19
AAQ-5 9.5 19.7 12.7 19.3 0.11 0.23 0.15 0.23
AAQ-6 9.5 14.5 11.5 14.3 0.11 0.19 0.15 0.18
AAQ-7 10.6 17.8 14.8 17.7 0.10 0.19 0.15 0.19
AAQ-8 9.3 19.7 12.7 18.4 0.10 0.21 0.15 0.20
AAQ-9 9.9 14.6 11.9 14.1 0.11 0.19 0.15 0.19
AAQ-10 9.5 12.8 11.4 12.8 0.11 0.19 0.14 0.19
AAQ-11 5.7 7.3 6.3 7.1 0.11 0.19 0.15 0.19
NAAQ Standards
80 2
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Figure 3.13: Variation of Particulate Matter PM10 in the study area
PM2.5: The maximum and minimum concentrations for PM2.5 were recorded as 45.1 g/m3 and 18.6 g/m3
respectively. The maximum concentration was recorded at Shapawada and Bilodra and the minimum
concentration was recorded at Ajol. The average values were observed to be in the range of 24.1g/m3.–
28.4 g/m3 as shown in figure 3.14.
Figure 3.14: Variation of Particulate Matter PM2.5 in the study area
0
20
40
60
80
100C
on
cen
trat
ion
µg/
m3
Sampling Locations
Particulate Matter PM10MinMaxMean98%le
0
10
20
30
40
50
Co
nce
ntr
atio
n µ
g/m
3
Sampling Locations
Particulate Matter 2.5 MinMaxMean98%le
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SO2: The maximum SO2 concentrations were recorded were recorded as 14.1 g/m3 and 5.1 g/m3
respectively. The maximum concentration was recorded at Sunsar and the minimum concentration was
recorded at most of the location as shown in figure 3.15. The average values were observed to be in the
range of 5.8 g/m3- 9.9 g/m3.
Figure 3.15: Variation of Sulphur di oxide (SO2 ) in the study area
NOX: The maximum and minimum NOX concentrations were recorded were recorded as 24.6 g/m3 and
5.7 g/m3 respectively. The maximum concentration was recorded at Chadasana and the minimum
concentration was recorded at Sunsar as shown in figure 3.16 The average values were observed to be
in the range of 6.3 g/m3 to 16.7 g/m3.
Figure 3.16: Variation of Oxides of Nitrogen (NOx) in the study area
0
5
10
15
Co
nce
ntr
atio
n µ
g/m
3
Sampling locations
Sulphur di oxide SO2MinMaxMean98%le
0
5
10
15
20
25
30
AAQ-1 AAQ-2 AAQ-3 AAQ-4 AAQ-5 AAQ-6 AAQ-7 AAQ-8 AAQ-9 AAQ-10 AAQ-11
Co
nce
ntr
atio
n µ
g/m
3
Sampling locations
Oxides of Nitrogen (NOx)MinMaxMean98%le
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CO: The maximum and minimum CO concentrations were recorded as 0.39 mg/m3 and 0.10 mg/m3
respectively. The maximum concentration was recorded at Chadasana and the minimum concentration
was recorded at most of the locations. The average values were observed to be in the range between
0.14mg/m3 to 0.28 mg/m3.
VOCs & BTX: The VOCs & BTX concentrations at all station in the study area were observed to below the
detection limit of 1 g/m3.
Methane HC: The Methane HC concentrations at all station in the study area were observed to be below
the detection limit of 0.1 g/m3.
Non Methane HC: The Non-Methane HC concentrations at all station in the study area were observed to
be below the detection limit of 0.1 g/m3.
The overall concentrations of PM10, PM2.5, SO2, NOX and CO were observed to be well within the standards
prescribed by Central Pollution Control Board (CPCB) for Industrial, Rural, Residential and other area.
3.8 Noise Environment
Noise can be defined as unwanted sound or any sound that is undesirable because it interferes with
speech and hearing, is intense enough to damage hearing or is otherwise annoying. From the noise
source, natural or man-made barriers between the source and the impacted population, weather
conditions which could potentially absorb, reflect, or focus sound (such as wind speed, direction,
temperature inversions), and the scale of industrial activity. The environmental impact of noise can vary
from noise induced hearing loss (NIHL) to annoyance depending on the loudness of noise levels and
tolerance levels of individual.
3.8.1 Methodology for Noise Monitoring
The sound level meter of HTC was used for measuring the Sound Pressure Level (SPL). Sound Pressure
Level (SPL) measurements were recorded at the specified locations continuously for 24 hours. The day
noise levels were recorded between 6 and 10 pm and night noise levels were recorded between 10 pm
and 6 am at all locations.
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3.8.2 Details of Noise Monitoring Locations & Presentation of Results
To quantify noise levels in the study area i.e., 1 km radius from the location, the following criteria was
followed to select sampling stations during field reconnaissance.
Human settlements near the location, which can be affected
Locations of Industrial, residential, commercial, and silence zones in the study area, as per the
CPCB guidelines.
Based on the reconnaissance, the noise quality monitoring stations were identified within the study total
95 locations have been monitored as shown in Figure 3.17; the details of the locations are given in Table
3.8.
Noise Monitoring Stations
Figure – 3.17: Map showing Noise Monitoring Stations
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Table 3.8: Noise level Monitoring of locations
Location Code
Name of the Location
Coordinates Classification of Location
Lday [dB(A)]
Lnight [dB(A)]
Leq [dB(A)]
Standard*
Latitude Longitude Day Night
N1 Near Indrap(1 Km WWN)
23°30'13.54"N
72° 7'34.20"E
Residential Area
48.7 42.0 47.4 55 45
N2 Near Chadsna
23°30'48.08"N
72° 6'18.62"E
Residential Area
53.2 41.1 51.6 55 45
N3 Near Dethali bus stop
23°28'44.55"N
72° 7'9.76"E Residential Area
53.6 42.0 52 55 45
N4 Rantej 23°28'47.23"N
72° 9'36.45"E
Residential Area
53.7 41.4 52.1 55 45
N5 Kakasana 23°37'39.18"N
72°14'3.26"E Residential Area
53.7 41.4 52.1 55 45
N6 Near Dudhsagar Dairy Kakasana
23°38'25.36"N
72°15'33.59"E
Industrial Area
52.9 40.9 51.3 75 70
N7 Near Motap 23°36'52.48"N
72°15'42.85"E
Residential Area
53 41.7 51.4 55 45
N8 Near Mitha Balol Conecting Road
23°32'8.39"N
72°16'28.02"E
Residential Area
54.1 41.3 52.5 55 45
N9 Near SH 216
23°32'8.51"N
72°17'47.45"E
Commercial Area
54.1 41.9 52.5 65 55
N10 Mitha 23°32'42.80"N
72°17'17.90"E
Residential Area
53.3 39.8 51.6 55 45
N11 Near Gujarat State Highway 218
23°37'44.63"N
72°33'41.18"E
Residential Area
52.8 40.5 51.2 55 45
N12 Near Visnagar Mansa Road
23°36'1.70"N
72°35'44.35"E
Residential Area
52.8 41.4 51.2 55 45
N13 Near Dhandusan
23°30'0.48"N
72°33'24.63"E
Residential Area
53.1 41.7 51.5 55 45
N14 Bilodra 23°31'40.02"N
72°38'58.92"E
Residential Area
53.5 41.6 51.9 55 45
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N15 Near Harnahoda
23°29'55.17"N
72°35'56.09"E
Residential Area
53.2 41 51.6 55 45
N16 Near Motipura
23°32'10.62"N
72°36'20.41"E
Residential Area
54.2 41.9 52.6 55 45
N17 Kherva 23°32'43.11"N
72°26'25.06"E
Residential Area
55.2 40.3 53.5 55 45
N18 Near Padharia
23°31'6.46"N
72°31'34.70"E
Residential Area
53.6 41.3 52 55 45
N19 Langhanaj 23°27'2.13"N
72°29'38.98"E
Commercial Area
53.8 41 52.2 65 55
N20 Gozaria 23°28'29.66"N
72°33'47.01"E
Commercial Area
54.4 42 52.8 65 55
N21 Saldi 23°25'27.58"N
72°31'38.51"E
Residential Area
54.0 40.4 52.3 55 45
N22 Mehsana 23°35'8.55"N
72°22'11.44"E
Commercial Area
53.2 41.7 51.6 65 55
N23 Jotana 23°28'13.68"N
72°17'31.92"E
Residential Area
52.9 38.8 51.2 55 45
N24 Memadpur 23°25'23.77"N
72°18'7.51"E Residential Area
54.5 39 52.8 55 45
N25 Jakasana 23°26'18.89"N
72°18'48.70"E
Residential Area
54.2 38.4 52.5 55 45
N26 Ambassan 23°28'44.78"N
72°20'54.56"E
Residential Area
51.5 38.9 49.9 55 45
N27 Linch 23°29'53.78"N
72°22'38.08"E
Residential Area
53.1 42 51.5 55 45
N28 Divanpura 23°26'39.06"N
72°21'13.11"E
Residential Area
53.7 41.9 52.1 55 45
N29 Suraj 23°23'30.41"N
72°18'18.20"E
Commercial Area
53.9 41.8 52.3 65 55
N30 Nani Kadi Part
23°16'9.03"N
72°19'22.20"E
Residential Area
54.4 41 52.7 55 45
N31 Kadi Railway Stn
23°17'32.31"N
72°19'30.99"E
Residential Area
53.4 40.1 51.7 55 45
N32 Irana 23°18'46.63"N
72°23'2.67"E Residential Area
52 40.5 50.4 55 45
N33 Dhinoj 23°39'43.19"N
72°16'44.41"E
Residential Area
53.8 41.7 52.2 55 45
N34 Lanva 23°41'2.23"N
72°14'40.26"E
Residential Area
54.8 42 53.2 55 45
N35 Rampura Bus Stop
23°33'50.87"N
72°25'29.68"E
Residential Area
53.2 41.8 51.6 55 45
N36 Ucharapi Rd
23°36'0.71"N
72°24'29.44"E
Commercial Area
52.3 41.8 50.7 65 55
N37 Mansa 23°26'0.66"N
72°39'23.37"E
Commercial Area
53 42 51.4 65 55
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N38 Ridrol 23°27'34.75"N
72°40'32.09"E
Commercial Area
52.9 41.6 51.3 65 55
N39 Ganeshpura
23°24'16.62"N
72°23'25.98"E
Residential Area
53.9 41.8 52.3 55 45
N40 Mathasur 23°23'4.33"N
72°22'15.74"E
Residential Area
54.9 40.9 53.2 55 45
N41 Kadi-nandsan Road
23°21'48.90"N
72°23'11.72"E
Residential Area
53.3 41.5 51.7 55 45
N42 Anandpura road
23°22'59.20"N
72°25'41.31"E
Residential Area
53.1 41.6 51.5 55 45
N43 Nandasan 23°22'16.59"N
72°24'29.36"E
Commercial Area
53.5 41.9 51.9 65 55
N44 Chanasma 23°43'7.10"N
72° 7'12.23"E
Commercial Area
53.6 41.4 52 65 55
N45 Balol 23°30'56.80"N
72°14'54.30"E
Residential Area
53.9 41.4 52.3 55 45
N46 Kasalpura 23°29'0.81"N
72°17'41.98"E
Residential Area
52.8 41.3 51.2 55 45
N47 Santhal 23°29'0.03"N
72°15'19.94"E
Commercial Area
53.9 40.5 52.2 65 55
N48 Hevuba 23°33'0.12"N
72°24'29.99"E
Residential Area
53.6 41.2 52 55 45
N49 Punasan 23°32'8.89"N
72°24'37.15"E
Residential Area
53.7 41.8 52.1 55 45
N50 Mevad 23°31'45.38"N
72°23'20.61"E
Residential Area
52.9 41.4 51.3 55 45
N51 Heduva Rajgar
23°33'53.62"N
72°21'5.29"E Residential Area
52.5 41.3 50.9 55 45
N52 Sukhpurda 23°32'36.30"N
72°22'23.06"E
Residential Area
53.2 41.6 51.6 55 45
N53 Katpur 23°47'55.12"N
72° 5'38.75"E
Residential Area
53.3 41.7 51.7 55 45
N54 Near Katosan
23°27'3.49"N
72°13'4.31"E Residential Area
52.8 41.5 51.2 55 45
N55 Katosan 23°27'40.80"N
72°13'9.05"E Residential Area
54 41.3 52.4 55 45
N56 Tejpura 23°27'57.94"N
72°12'30.09"E
Residential Area
53.8 41.1 52.2 55 45
N57 Amarpura 23°25'50.86"N
72°13'23.45"E
Residential Area
53.2 41.6 51.6 55 45
N58 Virsoda 23°26'25.98"N
72°11'40.70"E
Residential Area
53.4 41.4 51.8 55 45
N59 Moti Rantai 23°24'40.69"N
72°11'48.60"E
Residential Area
53.8 41.7 52.2 55 45
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N60 Madrisana 23°23'21.55"N
72°12'47.59"E
Residential Area
52 41.5 50.4 55 45
N61 Rampura
23°27'52.98"N
72°10'35.95"E
Residential Area
54.2 41.6 52.6 55 45
N62 Indrap 23°30'5.07"N
72° 8'8.51"E Residential Area
54.1 40.8 52.4 55 45
N63 Chadasna 23°30'35.69"N
72° 6'43.16"E
Commercial Area
51 41.5 49.5 65 55
N64 Dholasan 23°24'21.39"N
72°20'14.56"E
Residential Area
52.3 41.1 50.7 55 45
N65 Ganpatpura
23°23'45.74"N
72°19'27.92"E
Commercial Area
54.5 41.3 52.8 65 55
N66 Kadi GIDC 23°17'26.31"N
23°17'26.31"N
Commercial Area
53.9 40.1 52.2 65 55
N67 Kadi 23°17'52.33"N
72°19'51.61"E
Commercial Area
54 40.7 52.3 65 55
N68 Kasba 23°18'11.78"N
72°19'49.36"E
Residential Area
52.8 41.3 51.2 55 45
N69 Chalasan 23°24'16.25"N
72°18'10.76"E
Commercial Area
54.3 39 52.6 65 55
N70 Khara 23°31'41.28"N
72°17'52.08"E
Residential Area
53.4 38.5 51.7 55 45
N71 Devinapura 23°33'32.40"N
72°17'26.82"E
Residential Area
53.3 38.7 51.6 55 45
N72 Mahesana GIDC
23°35'25.33"N
72°22'20.31"E
Commercial Area
52.2 41.2 50.6 65 55
N73 Vidhyanagar
23°34'43.78"N
72°21'50.18"E
Residential Area
52.2 41 41 55 45
N74 Heduva 23°34'2.87"N
72°22'6.04"E Residential Area
52.9 41 51.3 55 45
N75 RTO 23°34'22.84"N
72°21'55.75"E
Commercial Area
53.3 41.1 51.7 65 55
N76 Palwasana Part
23°33'33.61"N
72°22'20.24"E
Residential Area
52.9 41.3 51.3 55 45
N77 Laghnaj 23°26'52.05"N
72°29'54.66"E
Commercial Area
52.6 39.8 51 65 55
N78 ONGC Nagar
23°36'7.61"N
72°22'34.75"E
Residential Area
54 41.6 52.4 55 45
N79 Suraj 23°23'25.39"N
72°18'40.00"E
Residential Area
52.7 39.8 51 55 45
N80 Mokasan 23°22'3.51"N
72°19'25.22"E
Residential Area
51.4 40.2 49.8 55 45
N81 Jagudan 23°30'49.26"N
72°24'57.72"E
Residential Area
54.1 40.4 52.4 55 45
N82 Kochava 23°30'15.54"N
72°25'9.34"E Residential Area
52.8 40.1 51.2 55 45
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Standard as per Environmental Protection Act 1986, the principle rules published for Ambient Noise
Level Standard (Area Category: Industrial/Residential/Commercial Area
N83 Baliasan 23°27'20.50"N
72°23'40.94"E
Residential Area
54 39 52.3 55 45
N84 Palwasana Part
23°33'20.60"N
72°22'4.03"E Residential Area
55.7 38.5 54 55 45
N85 Ranipura 23°27'34.55"N
72°18'59.79"E
Residential Area
54.3 38.9 52.6 55 45
N86 Lijpura Jethaji
23°26'32.20"N
72°17'25.93"E
Residential Area
53.7 38.7 52 55 45
N87 Memadpur 23°25'22.49"N
72°18'56.69"E
Residential Area
54.1 38.9 52.4 55 45
N88 Ganeshpura
23°38'6.04"N
72°19'8.61"E Residential Area
53.8 39 52.1 55 45
N89 Vadasma 23°24'36.37"N
72°29'17.78"E
Commercial Area
53.1 41.1 51.5 65 55
N90 Mandali 23°25'45.11"N
72°23'56.84"E
Residential Area
52 41.7 50.4 55 45
N91 Ganget 23°43'35.70"N
72°10'29.33"E
Residential Area
53.1 41.1 51.5 55 45
N92 Keshani 23°42'37.25"N
72°10'40.59"E
Residential Area
54.1 41.4 52.5 55 45
N93 Jasalpur 23°42'39.48"N
72° 7'12.23"E
Residential Area
54.1 41.5 52.5 55 45
N94 Suncity Society
23°36'9.29"N
72°22'15.36"E
Residential Area
53.8 41.8 52.2 55 45
N95 Near Gamanpura
23°32'58.62"N
72°16'11.13"E
Residential Area
53.1 40.4 51.5 55 45
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3.8.3 Observations
Day time Noise Levels
Noise levels during day time were found to be in the average range of 47.9 to 55.7 dB (A). The maximum
noise level was observed as 55.7 dB (A) at Palwasana Part (N-69) and a minimum of 48.7dB (A) was
observed at Near Near Indrap (N2).
Night time Noise Levels
Noise levels observed to fall in the range 38.4 to 42 dB (A) during the night time. A maximum of 42 dB
(A) was observed at Mansa (N-37), Lanva (N-34), Linch (N-27), Indrap (N-1) and a minimum of 38.4 dB
(A) was observed at Jakasana (N-75).
In residential zone the noise levels were found to meet the Ambient Air Quality Standards in respect of
Noise (henceforth Noise Standards 2000) as given in Noise Rules 2000, during day and night time. Within
the proposed location, the noise levels were within the OSHA damage risk criteria for hearing. The area
which is located at a lower elevation and has dense vegetation, which would prevent noise propagation
to nearby villages. Many of the activities such as construction, bus/auto station and traffic causing noise
are temporary in nature.
Figure 3.18: Noise Monitoring Locations
Noise 1- Near Chadsna Noise 2- Near Visnagar Mansa Road
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Noise 3-Mehsana Noise 4-Jotana
Noise 5- Balol Noise 6-Khara
Noise 7- Laghnaj Noise 8- Suraj
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3.9 Water Environment
3.9.1 Reconnaissance
A reconnaissance survey was undertaken to identify the sampling locations to establish baseline status
of water quality in the study area. Based on the reconnaissance survey, the type of water bodies and
their relative importance with the project site and environmental issues within study area; surface and
ground water sampling locations were identified and water samples were collected in summer season.
3.9.2 Water Quality Monitoring
Selected water quality parameters of the Ground water resources within the project area have been studied
for assessing the water environment. Water samples were examined for Physico-chemical, Heavy metals
and Bacteriological parameters in order to assess the effect of industrial, vehicular and other activities on
ground or surface water.
3.9.3. Sampling and Analysis Techniques
Samples for chemical analysis were collected in polyethylene carboys. Samples collected for metal content
were acidified with 1 ml HNO3. Samples for bacteriological analysis were collected in sterilized bottles. The
samples were analyzed as per the procedures specified in IS methods and 'Standard Methods for the
Examination of Water and Wastewater' published by American Public Health Association (APHA).
3.9.4 Details of Water Sampling Locations
Seven (7) Ground Water and Fourteen (14) Surface water samples were collected to establish baseline
water quality of the study area. The Ground water sampling locations are listed in the Table-3.9 & locations
for Surface water samples are listed in the Table 3.10
TABLE 3.9– GROUND WATER SAMPLING LOCATIONS
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Location Code Name of the Location
Coordinates Latitude Longitude
GW1 Fatepura 23°25'56.08"N 72°38'12.90"E
GW2 Sunsar 23°38'49.61"N 72°13'38.02"E
GW3 Suraj 23°23'41.02"N 72°18'49.36"E
GW4 Kherva 23°32'36.80"N 72°26'30.28"E
GW5 Rupal 23°41'3.68"N 72°20'35.16"E
GW6 Lagnaj 23°26'50.30"N 72°29'50.45"E
GW7 Linch 23°29'43.82"N 72°22'17.93"E
TABLE 3.10 – SURFACE WATER SAMPLING LOCATIONS
Location Code Name of the Location
Coordinates Latitude Longitude
SW1 Lodra 23°27'21.46"N 72°43'12.14"E
SW2 Ridrol 23°27'25.93"N 72°40'48.15"E
SW3 Kherva 23°32'47.80"N 72°26'25.50"E
SW4 Langhnaj
23°26'41.94"N 72°29'53.46"E
SW5 Rupal 23°41'5.12"N 72 20'34.41"E
SW6 Linch 23°29'34.72"N 72°22'26.79"E
SW7 Ubkal 23°34'11.49"N 72°37'34.25"E
SW8 Kadi 23°16'6.83"N 72°19'23.57"E
SW9 Rupal (Narmada canal)
23°41'15.69"N 72°20'30.91"E
SW10 Delwad
23°23'12.24"N 72°43'19.44"E
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SW11 Khari
23°34'23.75"N 72°21'2.86"E
SW12 Udhalpur
23°33'31.20"N 72°29'12.21"E
SW13 Motidau
23°40'59.42"N 72°24'8.25"E
SW14 Mansa
23°25'48.28"N 72°39'22.77"E
The study area map covering the Water sampling Locations is enclosed as Figure – 3.19,
Figure – 3.19: Map Showing Ground Water & Surface Water monitoring Stations
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3.9.5 Presentation of Results
The sampling results for the ground water and surface water samples were tabulated in Table – 3.11 &
Table 3.12 (a) & (b) respectively. The analysed results are compared with the Acceptable Drinking water
standard as per IS: 10500:2012 for both Ground water and Surface water.
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Table 3.11 (a): Results of Ground Water sampling locations
S.No Parameters Unit Procedure GW1 GW2 GW3 GW4 Acceptable Limit as per IS 10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) Nil 2 Nil 1 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 26.2 25.8 25.8 26.1 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012)
7.80 7.57 8.01 7.71 6.5-8.5
4 Electrical Conductivity
μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012)
863 2680 1080 1060 Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012)
0.5 1.2 BDL(<0.5) 0.8 1
6 Total Dissolved Solids
mg/l IS : 3025 Part 16-1984 (Reaff: 2012)
480 1512 610 604 500
7 Total Hardness as CaCO3
mg/l IS : 3025 Part 21-2009 (Reaff: 2014)
264 560 228 248 200
8 Total Alkalinity as CaCO3
mg/l IS : 3025 Part 23- 1986 (Reaff:2012)
260 330 250 268 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014)
105 645 220 195 250
10 Sulphate as SO4
mg/l APHA 22nd Edition -4500- SO42- E
14 128 9 11 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.58 0.99 1.22 0.56 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B
31 7.4 1.5 23 45
13 Ammonical Nitrogen
mg/l APHA 22nd Edition -4500- NH3 B&C
0.34 0.18 BDL(<0.05) 0.34 Not Specified
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14 Total Nitrogen as N
mg/l APHA 22nd Edition -4500- N&C,NO3 E
7.36 2.08 1 0.65 Not Specified
15 Total Phosphorous
mg/l IS : 3025 Part 31-1988 (Reaff:2014)
0.21 0.15 0.25 0.13 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014)
75 320 136 122 Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014)
3 10 6 5 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014)
53 104 46 45 75
19 Magnesium as Mg
mg/l APHA 22nd Edition-3500 Mg-B 32 73 27 33 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 BDL(< 0.05)
0.3 BDL(< 0.05)
0.165 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) 0.10
22 Dissolved Oxygen as O2
mg/l IS:3025:Part-38:1989 (Reaff:2003) 3.9 4.1 4.3 3.9 Not Specified
23 Chemical Oxygen Demand
mg/l IS:3025:Part-58:2006 (Reaff:2012)
BDL(<4) BDL(<4) BDL(<4) 4.4 Not Specified
24
Bio-Chemical Oxygen Demand @ 27°C for 3 days
mg/l IS:3025:Part-44:1993 (Reaff:2014)
<2 <2 <2 <2 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)
0.05
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26 Mercury as Hg mg/l APHA 22nd Edition -3112 B 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)
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)
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)
0.05
30 Lead as Pd mg/l APHA 22nd Edition -3111 B 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 0.019 0.24 0.156 0.278 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)
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) 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)
0.02
35 Sodium Absorption Ratio
_ Calculation 2.01 5.88 3.93 3.37 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.5 1.5 0.6 0.6 Not Specified
37 Calcium Hardness as CaCO3
mg/l IS:3025:Part-40:(Reaff:2014) 132 260 116 112 Not Specified
38 Magnesium Hardness as CaCO3
mg/l APHA 22nd Edition -3500 Mg B 132 300 112 136 Not Specified
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39 Molybdenum as Mo
mg/l APHA 22nd Edition -3111 D BDL(< 0.05)
BDL(< 0.05)
BDL(< 0.05)
BDL(< 0.05)
0.07
40 Total Coliform MPN/ 100ml
IS :1622 (1981) 6 <2 <2 26 Absent
41 Faecal coliform MPN/ 100ml
IS:1622 (1981) <2 <2 <2 <2 Absent
42. Total Suspended Solids
mg/l IS:3025 Part 17 <1 <1 <1 <1 Not Specified
Table 3.11 (b): Results of Ground Water sampling locations
S.No Parameters Unit Procedure GW5 GW6 GW7 Acceptable Limit as per IS 10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) 1 2 Nil 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 26.1 25.2 25.8 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 7.68 7.65 7.87 6.5-8.5
4 Electrical Conductivity
μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012)
2310 1350 1020 Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 1.3 1.5 BDL(<0.5) 1
6 Total Dissolved Solids
mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 1350 770 564 500
7 Total Hardness as CaCO3
mg/l IS : 3025 Part 21-2009 (Reaff: 2014) 396 292 228 200
8 Total Alkalinity as CaCO3
mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 390 288 260 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 540 260 180 250
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10 Sulphate as SO4
mg/l APHA 22nd Edition -4500- SO42- E 42 12 8 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 1.2 0.65 0.23 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B 28 17 41 45
13 Ammonical Nitrogen
mg/l APHA 22nd Edition -4500- NH3 B&C 0.43 0.41 0.12 Not Specified
14 Total Nitrogen as N
mg/l APHA 22nd Edition -4500- N&C,NO3 E
6.22 3.74 9.74 Not Specified
15 Total Phosphorous
mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.13 0.42 0.09 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 342 203 105 Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 4 4 3 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 58 61 43 75
19 Magnesium as Mg
mg/l APHA 22nd Edition-3500 Mg-B 61 34 48 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 0.195 0.216 BDL(<0.05) 1
21 Manganese as Mn
mg/l APHA 22nd EDN -3500-Mn D 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) 3.4 4.1 3.7 Not Specified
23 Chemical Oxygen Demand
mg/l IS:3025:Part-58:2006 (Reaff:2012) BDL(< 4)
BDL(< 4) 15 Not Specified
24
Bio-Chemical Oxygen Demand @ 27°C for 3 days
mg/l IS:3025:Part-44:1993 (Reaff:2014) <2 <2 <2 Not Specified
25 Copper as Cu mg/l APHA 22nd Edition -3111 B BDL(< 0.03)
BDL(< 0.03)
BDL(< 0.03)
0.05
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26 Mercury as Hg mg/l APHA 22nd Edition -3112 B 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)
0.003
28 Total Arsenic as As
mg/l APHA 22nd Edition -3114 B 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)
0.05
30 Lead as Pd mg/l APHA 22nd Edition -3111 B BDL(< 0.01)
BDL(< 0.01)
BDL(< 0.01)
0.01
31 Zinc as Zn mg/l APHA 22nd Edition -3111 B 0.06 0.272 0.316 5
32 Hexavalent Chromium as Cr6+
mg/l APHA 22nd Edition -3500 Cr B 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) 0.05
34 Nickel as Ni mg/l APHA 22nd Edition -3111 B BDL(< 0.02)
BDL(< 0.02)
BDL(< 0.02)
0.02
35 Sodium Absorption Ratio
_ Calculation 7.47 5.16 2.61 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 1.4 0.8 0.6 Not Specified
37 Calcium Hardness as CaCO3
mg/l IS:3025:Part-40:(Reaff:2014) 144 152 108 Not Specified
38 Magnesium Hardness as CaCO3
mg/l APHA 22nd Edition -3500 Mg B 252 140 120 Not Specified
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39 Molybdenum as Mo
mg/l APHA 22nd Edition -3111 D BDL(< 0.05)
BDL(< 0.05)
BDL(< 0.05)
0.07
40 Total Coliform MPN/ 100ml
IS :1622 (1981) <2 4 23 Absent
41 Faecal coliform MPN/ 100ml
IS:1622 (1981) <2 <2 <2 Absent
42. Total Suspended Solids
mg/l IS:3025 Part 17 <1 1 <1 Not Specified
TABLE –3.12 (a): SURFACE WATER ANALYSIS RESULTS
S.N
o Parameters Unit Procedure
SW1 SW2 SW3 SW4 SW5
Acceptable Limit as
per IS 10500:2012
1 Colour Hazen APHA 22nd Edition (Reaff:2012) 10 55 15 3 8 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 26 25.3 26.5 26.3 25.6 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 7.14 7.3 7.47 7.3 7.16 6.5-8.5
4 Electrical Conductivity μS/cm IS : 3025 Part 14- 1984 (Reaff: 2012) 270 1532 1070 520 1630 Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 6.6 14.1 12.8 2.2 7 1
6 Total Dissolved Solids mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 325 858 612 290 930 500
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7 Total Hardness as
CaCO3 mg/l IS : 3025 Part 21-2009 (Reaff: 2014)
132 330 180 160 240
200
8 Total Alkalinity as CaCO3 mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 160 252 260 160 190 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 75 303 190 67 381 250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500- SO42- E 8 76 21 8 58 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.49 0.56 0.49 0.19 0.55 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B 21 39 16 11 19 45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3 B&C 2.63 0.53 2.23 1.36 3.11 Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500- N&C,NO3
E
8.36 21.8 5.14 4.13 9.63
Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.51 0.13 0.64 0.11 0.5 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 60 169 142 45 216 Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 13 20 17 5 25 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 24 56 32 30 40 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 17 46 24 20 34 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 1.96 5.46 1.21 2.89 3.88 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D
BDL(< 0.02)
0.07
BDL(
<
0.02)
0.07
0.2 0.09
0.10
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22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 4.8 4.8 5.5 6.6 5.1 Not Specified
23 Chemical Oxygen
Demand mg/l IS:3025:Part-58:2006 (Reaff:2012)
28 40 54 17 33 Not Specified
24
Bio-Chemical Oxygen
Demand @ 27°C for 3
days
mg/l IS:3025:Part-44:1993 (Reaff:2014)
4.9
6.2 8.2 2.1 4.4 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) 0.12 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 Pd mg/l APHA 22nd Edition -3111 B 0.013 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 0.396 0.71 0.841 0.214 0.166 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 2.29 4.05 4.62 1.56 6.06 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.4 0.9 1.1 0.3 1.6 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014)
60 140 80 76 100 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B
72 190 100 84 140 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)
170 17 350 90 110 Absent
41 Faecal coliform MPN/
100ml IS:1622 (1981)
33 4 17 11 14 Absent
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TABLE – 3.12 (b): SURFACE WATER ANALYSIS RESULTS
S.No Parameters Unit Procedure SW6 SW7 SW8
SW9 SW10
Acceptable
Limit as per
IS 10500:2012
1 Colour Haze
n APHA 22nd Edition (Reaff:2012) 25 6 6
3 2 5
2 Temperature °C APHA 22nd Edition (Reaff:2012) 26.8 25.7 26.6 25.7 25.4 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983 (Reaff:2012) 7.42 7.31 7.39 6.69 7.38 6.5-8.5
4 Electrical Conductivity μS/c
m
IS : 3025 Part 14- 1984 (Reaff:
2012) 1590 990 941
394 291
Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff: 2012) 10.8 2.2 3.3 2 1.5 1
6 Total Dissolved Solids mg/l IS : 3025 Part 16-1984 (Reaff: 2012) 890 562 522 211 161 500
7 Total Hardness as CaCO3 mg/l IS : 3025 Part 21-2009 (Reaff: 2014) 220 120 210 124 110 200
8 Total Alkalinity as CaCO3 mg/l IS : 3025 Part 23- 1986 (Reaff:2012) 240 240 270 121 100 200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff: 2014) 317 116 135 44 27 250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500- SO42- E 96 65 32 16 11 200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F B&D 0.64 0.81 0.74 0.36 0.63 1
12 Nitrate as NO3 mg/l APHA 22nd Edition -4500- NO3- B 5 1.7 BDL(<1) BDL(<1) BDL(<
1)
45
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13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3
B&C 1.44 1.36 0.14
0.1 0.05
Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500-
N&C,NO3 E 2.63 2.05 2
1.11 1
Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988 (Reaff:2014) 0.46 0.31 0.2 0.03 0.32 Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993 (Reaff:2014) 220 140 96 29 15 Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993 (Reaff:2014) 27 33 11 9 3 Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991 (Reaff:2014) 20 16 44 27 24 75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 41 19 40 13 13 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 1.41 0.31 0.41 0.26 0.25 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)
BDL(<
0.02) 0.10
22 Dissolved Oxygen as O2 mg/l IS:3025:Part-38:1989 (Reaff:2003) 4.8 5.9 6.5 6.7 6.5 Not Specified
23 Chemical Oxygen
Demand mg/l IS:3025:Part-58:2006 (Reaff:2012) 60 16 12
18 16 Not Specified
24
Bio-Chemical Oxygen
Demand @ 27°C for 3
days
mg/l IS:3025:Part-44:1993 (Reaff:2014) 10.4 2 2
2.4
2.2 Not Specified
25 Copper as Cu mg/l APHA 22nd Edition -3111 B 0.11 BDL(<0.03 BDL(<0.0
3)
BDL(<0.
03)
BDL(<
0.03 0.05
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26 Mercury as Hg mg/l APHA 22nd Edition -3112 B BDL(<
0.001)
BDL(<0.001
)
BDL(<0.0
01)
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(<0.0
03)
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 Pd 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 0.123 0.17 0.21 0.14 5
32 Hexavalent Chromium as
Cr6+ mg/l APHA 22nd Edition -3500 Cr B
BDL(<0.0
1) BDL(<0.01)
BDL(<0.0
1)
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 6.47 5.60 2.52 1.15 0.61 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.9 0.6 0.5 0.2 0.3 Not Specified
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37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 50 40 110
68 60 Not Specified
38 Magnesium Hardness as
CaCO3 mg/l APHA 22nd Edition -3500 Mg B 170 80 100
56 50 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/
100m
l
IS :1622 (1981) 280 140 60
23
50 Absent
41 Faecal coliform
MPN/
100m
l
IS:1622 (1981) 9 9 9
4
11 Absent
TABLE – 3.12 (c): SURFACE WATER ANALYSIS RESULT
S.No Parameters Unit Procedure SW11
SW12 SW13 SW14
Acceptable
Limit as per
IS 10500:2012
1 Colour Hazen APHA 22nd Edition
(Reaff:2012) 3
12
12 25 5
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2 Temperature °C APHA 22nd Edition
(Reaff:2012) 25.7
25.8
25.1 25.4 Not Specified
3 pH at 25°C - IS : 3025 Part 11- 1983
(Reaff:2012) 7.52
7.05 7.25 7.06 6.5-8.5
4 Electrical
Conductivity μS/cm
IS : 3025 Part 14- 1984 (Reaff:
2012) 378
568 2220 789
Not Specified
5 Turbidity NTU IS : 3025 Part 10-1984 (Reaff:
2012) 1.9
5.2 8.2 7.6
1
6 Total Dissolved
Solids mg/l
IS : 3025 Part 16-1984 (Reaff:
2012) 251
318 1288 442
500
7 Total Hardness as
CaCO3 mg/l
IS : 3025 Part 21-2009 (Reaff:
2014) 128
122 450 160
200
8 Total Alkalinity as
CaCO3 mg/l
IS : 3025 Part 23- 1986
(Reaff:2012) 176
171 391 177
200
9 Chloride as Cl mg/l IS : 3025 Part 32-1988 (Reaff:
2014) 32
61 407 101
250
10 Sulphate as SO4 mg/l APHA 22nd Edition -4500-
SO42- E 16
21 120 48
200
11 Fluoride as F mg/l APHA 22nd Edition-4500-F
B&D 0.59
0.46 0.54 0.58
1
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12 Nitrate as NO3 mg/l APHA 22nd Edition -4500-
NO3- B BDL(< 1)
1 14 13
45
13 Ammonical Nitrogen mg/l APHA 22nd Edition -4500- NH3
B&C 0.13
0.36 0.22 0.26
Not Specified
14 Total Nitrogen as N mg/l APHA 22nd Edition -4500-
N&C,NO3 E 1.42
1.21 8.21 6.97
Not Specified
15 Total Phosphorous mg/l IS : 3025 Part 31-1988
(Reaff:2014) 0.02
0.26 0.08 0.49
Not Specified
16 Sodium as Na mg/l IS : 3025 Part 45-1993
(Reaff:2014) 45
53 282 70
Not Specified
17 Potassium as K mg/l IS : 3025 Part 45-1993
(Reaff:2014) 11
25 22 39
Not Specified
18 Calcium as Ca mg/l IS : 3025 Part 40-1991
(Reaff:2014) 27
25 108 42
75
19 Magnesium as Mg mg/l APHA 22nd Edition-3500 Mg-B 14 15 44 14 30
20 Iron as Fe mg/l IS : 3025 Part 53-2003 0.74 1.61 2.07 2.96 1
21 Manganese as Mn mg/l APHA 22nd EDN -3500-Mn D BDL(< 0.02)
0.07
0.05
BDL0.
09(<
0.02) 0.10
22 Dissolved Oxygen as
O2 mg/l
IS:3025:Part-38:1989
(Reaff:2003) 5.7
4.9 6.1 5.1
Not Specified
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23 Chemical Oxygen
Demand mg/l
IS:3025:Part-58:2006
(Reaff:2012) 32
40 14 36 Not Specified
24
Bio-Chemical
Oxygen Demand @
27°C for 3 days
mg/l IS:3025:Part-44:1993
(Reaff:2014) 5.2
5.4
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) 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) 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) 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) 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) 0.05
30 Lead as Pd mg/l APHA 22nd Edition -3111 B 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 0.24 0.63 0.25 0.17 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) Not Specified
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33 Total Chromium as
Cr mg/l APHA 22nd Edition -3111 B
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) 0.02
35 Sodium Absorption
Ratio _ Calculation 1.74
2.06 5.77 2.38 Not Specified
36 Salinity %0 APHA 22nd Edition -2520 B 0.3 0.3 1.3 0.5 Not Specified
37 Calcium Hardness as
CaCO3 mg/l IS:3025:Part-40:(Reaff:2014) 68
62 270 104 Not Specified
38 Magnesium
Hardness as CaCO3 mg/l APHA 22nd Edition -3500 Mg B 68
60 180 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) 0.07
40 Total Coliform MPN/
100ml IS :1622 (1981) 240
900 170 500 Absent
41 Faecal coliform MPN/
100ml IS:1622 (1981) 23
80 23 50 Absent
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3.9.6 Observations
Ground Water
The pH value of the collected ground water in the study area found to be in the range from 7.57 to 8.01
and conductivity observed in the range 863 µS/cm to 2680 µS/cm. TDS values were observed to be in
range from 480 mg/L to 1512 mg/ L. Total alkalinity is found to be the range from 250 mg/L to 330 mg/L
and Total Hardness ranges from 228 to 560 mg/L. The chloride values of the samples were observed
from 105 mg/L to 645 mg/L and Sulphate values were observed from 8 mg/L to 128 mg/L. The Calcium
and magnesium values were ranged from 43 mg/L to 104 mg/L and 27 mg/L to 73 mg/L respectively. Iron
content observed in the range from BDL (<0.05) mg/l to 0.3 mg/l. Most of the metals are observed as
below the detection limit. Total Coliforms were observed up to 26 MPN/100ml and Faecal Coliforms were
observed <2 MPN/100ml at all locations.
Surface Water
The pH value of the collected surface water in the study area found to be in the range from 6.61 to 7.52
and conductivity observed in the range 270 µS/cm to 2220 µS/cm. TDS values were observed to be in
range from 184 mg/L to 1288 mg/ L. Total alkalinity is found to be the range from 121mg/L to 391mg/L
and Total Hardness ranges from 112 to 450 mg/L. The chloride values of the samples were observed
from32 mg/L to 407 mg/L and Sulphate values were observed from 8 mg/L to 120 mg/L. The Calcium
and magnesium values were ranged from 16 mg/L to 108 mg/L and 12.5 mg/L to 46 mg/L respectively.
Iron content found in the range from 0.26 mg/L to 5.46 mg/l. COD values observed in the range from 12
mg/l to 60 mg/l. Most of the metals are observed to be within the detection limit. Total Coliforms were
observed from 17 MPN/100ml to 900 MPN/100ml and Fecal Coliforms were observed from 4 MPN/100ml
to 80 MPN/100ml.
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GW-1 FATEPURA GW- 3 SURAJ
GW-4 KHERVA GW-5 RUPAL
GW-6 LAGNAJ GW-7 LINCH
Figure 3.20 Ground Water Sampling locations
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SW-1 LODRA SW-2 RIDROL
SW-5 RUPAL SW-8 KADI (NARMADA CANAL)
SW-12 UDALPUR SW-14 MANSA
Figure 3.21 Surface Water Sampling locations
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3.10 Soil Quality
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 eight (8) locations as tabulated in Table 3.13.
TABLE 3.13: SOIL SAMPLING LOCATIONS
Location Code Name of the Location Coordinates
Latitude Longitude
S1 Dholasan 23°24'15.21"N 72°20'31.35"E
S2 Ridrol 23°27'52.92"N 72°40'22.25"E
S3 Fatepura 23°25'50.10"N 72°38'11.60"E
S4 Kherva 23°32'40.63"N 72°26'39.67"E
S5 Lagnaj 23°27'2.82"N 72°29'56.61"E
S6 Rupal 23°41'8.83"N 72°20'29.62"E
S7 Susar 23°38'52.11"N 72°13'41.66"E
S8 Linch 23°29'43.65"N 72°22'17.26"E
The study area map covering the Soil Sampling Locations is enclosed as Figure – 3.26
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Soil Sampling Stations
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-3.14
TABLE 3.14 (a)- Soil Analysis Results
S.No Parameters Test Method S1 S2 S3 S4
1 pH (1:5 Suspension) IS -2720(Part 26) 1987
(RA 2016) 7.03
6.84 6.49
6.96
2 Moisture, % IS -2720(Part 2)
1987(RA 2015) 0.98
1.31 1.08
1.18
3 Porosity, % IS -2720 (Part 36) 32.1 36.4 30.8 28.8
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4 Water Holding
Capacity,%
Soil Chemical Analysis
By M. L. Jackson 32.6
35.1 32.8
25.8
5 Permeability, cm/hr Soil Chemical Analysis
By M. L. Jackson 1.7
1.3 1.8
1.2
6 Cation Exchange
Capacity, m.eq/100g
IS -2720(Part 24) (RA
2015) 12.6
18.7 24.8
26.9
7 Electrical conductivity,
mS/cm (1:5 Suspension)
IS -14767:2000 (RA
2016) 0.246
0.142 0.672
0.078
8 Exchangeable Calcium
as Ca, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 4 4.51
9.85 35.5
33.1
9 Exchangeable Magnesiu
m as Mg, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 5 8.95
7.3 10.7
12.15
10 Exchangeable Sodium as
Na, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 6 5.2
4.15 5.28
10.3
11 Potassium as K, Kg/ha FAO Chapter 3,
ABCTL/SOIL/SOP 7 1852
1688 1618
1892
12 Texture Classification IS -2720(Part 26)
1987(RA 2011)
Silt
Loam
Silty
Clay
loam
Loam
Clay
Loam
13 Sand (%)
Robinson Pipette Method
24.1 18.4 32.4 27.2
14 Clay (%) 21.6 24.6 28.6 35.1
15 Silt (%) 54.3 57 39 37.7
16 Sodium Absorbtion ratio Calculation 6.35 4.49 3.48 6.85
17 Available phosphorus as
P, kg/ha FAO Chapter 3, ABCTL/SOIL/SOP2 13.7
20.7
17
41.8
18 Available Nitrogen as N,
kg/ha FAO Chapter 3, ABCTL/SOIL/SOP11 236
207
263
310
19 Total Nitrogen as N,
kg/ha IS-14684:1999, Reaff:2008 309
271
352
407
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TABLE 3.14 (b)- Soil Analysis Results
S.No Parameters Test Method S5 S6 S7 S8
1 pH (1:5 Suspension) IS -2720(Part 26) 1987
(RA 2016) 7.48 6.89 6.53 6.73
2 Moisture, % IS -2720(Part 2) 1987(RA
2015) 1.05 1.36 1.2 1.47
3 Porosity, % IS -2720 (Part 36) 26.8 34.1 36.6 26.8
4 Water Holding Capacity,% Soil Chemical Analysis By
M. L. Jackson 19.6 31.8 36.9 14.4
5 Permeability, cm/hr Soil Chemical Analysis By
M. L. Jackson 2 0.23 0.21 0.41
6 Cation Exchange Capacity,
m.eq/100g
IS -2720(Part 24) (RA
2015) 21.8 32.8 30.7 9.66
7 Electrical conductivity,
mS/cm (1:5 Suspension) IS -14767:2000 (RA 2016) 0.606 0.343 0.508 0.107
8 Exchangeable Calcium as
Ca, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 4 41.7 7.06 12 154
9 Exchangeable Magnesium a
s Mg, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 5 12.1 12.25 14.3 11.92
10 Exchangeable Sodium as
Na, m.eq/100g
FAO Chapter 3,
ABCTL/SOIL/SOP 6 10.7 5 8.82 7.61
11 Potassium as K, Kg/ha FAO Chapter 3,
ABCTL/SOIL/SOP 7 3649 1816 2102 1809
12 Texture Classification IS -2720(Part 26) 1987(RA
2011) Loam Clay Clay
Sandy
Loam
13 Sand (%)
Robinson Pipette Method
27.1 25.8 29.6 55.6
14 Clay (%) 26.8 51.8 47.6 17.1
15 Silt (%) 46.1 22.4 22.8 27.3
16 Sodium Absorbtion ratio Calculation 6.53 5.10 7.70 2.64
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Source: ABC Techno Labs India Private Limited
3.10.4 Observations:
It has been observed that the pH of the soil is ranging from 6.49 to 7.48 while the soil texture is shown in
figure 3.27. Moisture found in the range from 0.98 to 1.47%. Conductivity of the soil ranges from 0.078
to 0.672 mS/cm. Texture of the soil in the selected locations of study area were found to be Silty Loamy
to Sandy Loamy in nature. The potassium content varies from 1618 to 3649 kg/ ha. Exchangeable
Sodium content varies from 4.15 to10.3 m.eq/100g. Exchangeable calcium and Exchangeable
magnesium were found in the range between 4.51 to 154 m.eq/100g & 7.3 to 14.3 m.eq/100g
respectively.
Figure 3.23: Particle Size distribution of soil sample
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 area predominant soil group is of Loamy soil. It has been
observed that infiltration rate in the loamy soil is high.
0
20
40
60
S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8
Val
ue(
%)
Soil Samples
Particle Size distributionSand (%)Clay (%)Silt (%)
17 Available phosphorus as P,
kg/ha FAO Chapter 3, ABCTL/SOIL/SOP2 36.9 54.7 41.8 21.8
18 Available Nitrogen as N,
kg/ha FAO Chapter 3, ABCTL/SOIL/SOP11 284 346 294 255
19 Total Nitrogen as N, kg/ha IS-14684:1999, Reaff:2008 391 505 399 375
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S1-DHOLASAN S3-FATEPURA
Soil 4-KHERVA Soil 6-RUPAL
Soil 7-SUNSAR Soil 8-LINCH
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.
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.