EIA REPORT AFTER PUBLIC HEARING. Sponsor : M/s. Oil and Natural Gas Corporation Ltd. Assam & Assam Arakan Basin, Cinnamara, Jorhat

Transcription

1 ENVIRONMENTAL IMPACT ASSESSMENT STUDIES FOR PROPOSED EXPLORATORY DRILLING OF 2 WELLS IN EXISTING NELP BLOCK AA-ONN-2001/2, KOLASIB & MAMIT DISTRICT, MIZORAM EIA REPORT AFTER PUBLIC HEARING Sponsor : M/s. Oil and Natural Gas Corporation Ltd. Assam & Assam Arakan Basin, Cinnamara, Jorhat Prepared by : 142 IDA, Phase-II, Cherlapally, Hyderabad env@vimta.com, (NABET - QCI Accredited, NABL Accredited & ISO Certified Laboratory, Recognized by MoEF&CC, New Delhi) May, 2018

2 PREFACE M/s. Oil and Natural Gas Corporation Ltd. Assam & Assam Arakan Basin, Cinnamara, Jorhat ENVIRONMENTAL IMPACT ASSESSMENT STUDIES FOR THE PROPOSED EXPLORATORY DRILLING OF 2 WELLS IN EXISTING NELP BLOCK AA-ONN-2001/2 KOLASIB AND MAMIT DISTRICT, MIZORAM For and on behalf of VIMTA Labs Limited Approved by : M. Janardhan Signature : Designation : Head & Vice President (Env) Date : 16 th May, 2018 The report has been prepared inline with the prescribed TOR s issued vide No. F.No.J-11011/305/2014-IAII(I) dated 6th January 2016, Extension of Validity of TOR and amendment in TOR issued dated 16th April 2018 and 27th April 2018 by Ministry of Environment, Forest and Climate Change (MoEF&CC), New Delhi. This report has been prepared by Vimta Labs Limited with all reasonable skill, care and diligence within the terms of the contract with the client, incorporating our General Terms and Conditions of Business and taking account of the resources devoted to it by agreement with the client.

3 Table of Contents Table of Contents Chapter Title Page Table of Contents List of Figures List of Tables Executive Summary TC-1 TC-4 TC Introduction 1.1 Purpose of the Report C Identification of Project & Project Proponent C Brief Description of the Project C Scope of the Study C Project Description 2.1 Introduction C Type of the Project C Need for Exploratory Drilling C Project Location and Layout Details C Size or Magnitude of Operation C Proposed Schedule for Project Approval and Implementation C Technology and Drilling Process Description C Details of Project Utilities C Post Drilling Operations Abandonment and Restoration C Sources of Pollution C Qualifications, Skills and Training Practice C Baseline Environmental Status 3.1 Introduction C Geology and Hydrogeology C Landuse Studies C Soil Characteristics C Meteorology C Ambient Air Quality C Water Quality C Noise Level Survey C Ecological Studies C Demographic and Socio-economics C Impact Assessment and Mitigation Measures 4.1 Impact Assessment C Anticipated Impacts from the Project C Environment Management Plan C Monitoring Environmental Performance C Emergency Response and Contingency Planning C4-31 VIMTA Labs Limited, Hyderabad TC-1

4 Table of Contents Table of Contents (Contd.) Chapter Title Page 4.6 Waste Management Plan C Drilling Site Restoration Plan C Analysis of Alternatives 5.1 Alternative for Technology C Alternatives for Project site C Environmental Monitoring Programme 6.1 Introduction C Environmental Monitoring and Reporting Procedure C Reporting Schedule of the Monitoring Data C Infrastructure for Monitoring of Environmental Protection Measures C Environmental Costs C Audit and Review C Additional Studies 7.1 Risk Assessment C Recommendations to Mitigate Risk/Hazards C Disaster Management Plan C Emergency Response Action C Emergency Response Procedures C End of Emergency C Communications C Project Benefits 8.1 Improvement in the Physical Infrastructure C Improvement in the Social Infrastructure C Employment Potential C Administrative Aspects 9.1 Operational Philosophy C Health Safety and Environment C Environmental Organization and Personnel C9-4 VIMTA Labs Limited, Hyderabad TC-2

5 Table of Contents Table of Contents (Contd.) Chapter Title Page 10.0 Summary and Conclusion 10.1 Location Details of the Project C Importance of the Proposed Project C Details of Exploration Drilling Operations C Baseline Environmental Status C Impact Assessment C Environment Management Plan C Environmental Monitoring Program C Risk Assessment and Disaster Management Plan C Project Benefits C Administrative Aspects C Conclusions C Disclosure of Consultants 11.1 Introduction C Vimta Labs Limited C11-1 List of Annexures Annexure-I Terms of Reference Letter and Compliance Annexure-II(A)Extension of Validity of TOR Annexure-II(B)Amendment in TOR Annexure-III Applicable Environmental Standards Annexure-IV Methodology for Sampling and Analysis Annexure-V Land use Pattern Annexure-VI Ambient Air Quality Levels Annexure-VII Demographic Details Annexure-VIII Emission Calculations Annexure-IX Pool Fire Calculations Annexure-X Secondary Data for Risk Analysis Annexure-XI CSR Expenditure Annexure-XII Corporate Environment Policy VIMTA Labs Limited, Hyderabad TC-3

6 Table of Contents List of Figures Figure Title Page 1.1 Index Map C Topographic Map NEPL Block in Kolasib & Mamit District C Google Map Showing Well Locations in NELP Block C Topographic Map HOAC Well 10 km radius C Topographic Map HOAD Well 10 km radius C Typical Layout of Well Site C Drilling Rig C Drilling Fluid Circulation System at Typical Rig C Typical Section View of Drilling Cut and Drill Mud Collection Pit C Hydrogeology Map of Kolasib District C Hydrogeology Map of Mamit District C Satellite Imagery of the Block Area C Landuse Pattern Based on Satellite Data C Soil Sampling Locations C Soil Sampling Photographs C IMD Agartala Pre Monsoon Season C IMD Agartala Monsoon Season C IMD Agartala Post Monsoon Season C IMD Agartala Winter Season C IMD Agartala- Annual Wind rose C Site Specific Windrose Winter Season C Air Quality Sampling Locations C Air Monitoring Photographs C Water Sampling Locations C Water Sampling Photographs C Noise Monitoring Locations C Noise Monitoring Photographs C Ecological Sampling Locations C Short Term 24 hourly GLCs of SO2 C Short Term 24 hourly GLCs of NOx C Noise Level Contours C Objectives of Risk Assessment C Methodology of MCA Analysis C Flow Chart for Evaluation of Consequences of Release of Flammable or Toxic Chemical C Emergency Classification C Contingency Plan for Onshore Blowout (Drilling Rig) C Typical Schematic of BOP Stack C Organizational Structure for Environmental Management C9-6 VIMTA Labs Limited, Hyderabad TC-4

7 Table of Contents List of Tables Tables Title Page 1.1 Block Coordinates C Tentative Well Locations C Environmental Setting of Well HOAC (10 Km Radius) C Environmental Setting of Well HOAD (10Km Radius) C Environmental Attributes and Frequency of Monitoring C Block Co-ordinates C Tentative Well Locations C Salient Features of the Proposed Exploratory Drilling in NELP Block of Mizoram C Water Requirements per Well Site C Details of DG Sets C Constituents of Water Based Mud (WBM) C Special Additives and Their Functions in Water Based Mud C Composition and Parameters of Water Based Drilling Mud C Hole Size and Casing Details C The Dynamic Groundwater Resources as on C Landuse /Land Cover Classification System C Land Use Break Up of the Study Area C Details of Soil Sampling Locations C Soil Analysis Results C Standard Soil Classification C Sensitivity of Meteorology Monitoring Equipment C Climatological Data Station IMD, Agartala C Summary of the Meteorological Data Generated at Site C Details of Ambient Air Quality Monitoring C Summary of Ambient Air Quality Results C Details of Water Sampling Location C Surface Water Quality C Ground Water Quality C Details of Noise Monitoring Location C Noise Levels in the Study Area C Ambient Noise Standards C Forest Blocks within Study Area C Details of Proposed Drilling Locations C Details of Terrestrial Ecological Sampling Locations C List of Agricultural Crops C Details of Aquatic Sampling Locations C List of Phytoplankton Species Identified from Study Area C List of Zooplankton Species Identified from Study Area C Distribution of Population in the study area C Distribution of Population by Social Structure C Distribution of Literate and Literacy Rates C Occupational Structure C Summary of Impact Assessment: Soil and Landuse C Details of DG Sets C Emission Characteristics Model Inputs C Predicted 24 Hourly Short Term Incremental Concentration C4-8 VIMTA Labs Limited, Hyderabad TC-5

8 Table of Contents List of Tables (Contd ) Tables Title Page 4.5 Resultant Concentrations due to Incremental GLC s C Summary of Impact Assessment: Water Resources C Input Data for Noise Modeling C Predicted Noise Levels C Noise Exposure Levels & Its Effects C Summary of Impact Assessment: Flora and Fauna C Summary of Environmental Management Actions C Schedule of Environmental Monitoring C List of Major Hazards C Occupational Hazards C Damage due to Peak over Pressure C Damage due to Incident Radiation Intensities C Input Data for Consequence Analysis C Summary of Consequence Analysis for Jet Fire Scenario at Well C Probability of Ignition for Leaks of Flammable Fluids C The Adnoc Individual Risk Assessment Criteria C Recommendations to Mitigate Blow out Risk/Hazards C7-11 VIMTA Labs Limited, Hyderabad TC-6

9 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction 1.0 INTRODUCTION Oil and Natural Gas Corporation Limited (ONGC) proposes to carryout exploratory drilling in NELP Block AA-ONN-2001/2, Kolasib and Mamit District, Mizoram. This chapter describes the purpose of the report, identification of project and proponent, brief description of nature, size, location of the project and importance to the region and country. The chapter also describes the scope of the study, details of regulatory scoping carried out as per Terms of Reference (TOR) issued by Ministry of Environment Forests (MoEF), New Delhi. 1.1 Purpose of the Report As per Environmental Impact Assessment EIA Notification dated 14 th September, 2006, exploration of oil & gas falls under category A of project activity 1(b) requires prior Environmental Clearance (EC) to be obtained from MoEF before the commencement of ground activity. The application for prior EC (Form-1 and Pre-feasibility Report) for the proposed project has been submitted to MoEF&CC on 17 th September 2014 and same was reviewed by the Expert Appraisal Committee (Industry II) held during 29 th -30 th October 2014 in New Delhi to prescribe Terms of Reference (TORs) for the preparation of EIA/EMP report. TOR with exemption of public hearing for the Kolasib district has been issued by MoEF vide letter reference F.No.J /305/2014-IA II (I) dated 6 th January A copy of the ToR letter, along with its compliance is enclosed as Annexure-I. This EIA Report is prepared inline 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 15 th January 2016 to 8 th April 2016 representing partly winter and partly pre monsoon season. ONGC obtained extension of validity of TOR vide letter reference F.No.J /305/2014-IA II (I) dated 16 th April The copy of the extension of validity of TOR is enclosed as Annexure-II (A). Further, ONGC intends to drop the 2 wells location (BRBAA & AZAA) out of 4 locations and online application (proposal no. IA/MZ/IND/2340/2014) has been submitted to MoEF&CC on 3 rd January 2018 for ToR amendment. The proposal was reviewed by the Expert Appraisal Committee (Industry II) in its 34 th meeting held during 26 th 28 th February 2018 and amendment has been issued vide letter reference F.No.J-11011/305/2014-IA II (I) dated 16 th April The ToR amendment letter copy is enclosed as Annexure-II (B). 1.2 Identification of Project and Project Proponent 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 VIMTA Labs Limited, Hyderabad C1-1

10 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction of Petroleum and Natural Gas. 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. With a market capitalization of over INR 2 trillion, it is one of India's most valuable publicly-traded companies. ONGC has been ranked 357 th in the Fortune Global 500 list of the world's biggest corporations for the year It is also among the Top 250 Global Energy Company by PLATTS. ONGC was founded on 14 August 1956 by the Indian state, which currently holds a 69.23% equity stake. It is involved in exploring hydrocarbons in 26 sedimentary basins of India, and owns and operates over 11,000 kilometers of pipelines in the country. Its international subsidiary, ONGC Videsh currently has projects in 15 countries. 1.3 Brief Description of the Project Nature of the Project As per the Environment Impact Assessment (EIA) Notification dated 14 th September, 2006, the proposed exploratory drilling project falls under Category A of Activity Type 1(b). The proposed project intends to identify the presence of hydrocarbon prospects through exploratory drilling and to delineate and quantify hydrocarbon pools in discovered fields through exploratory drilling. The proposed project will basically involve drilling of 2 exploratory wells in the block Size of the Project ONGC has identified two well locations HOAC and HOAD are included in present EIA study. It is proposed to drill two exploratory wells for the fulfillment of Minimum Work Program (MWP) and also to evaluate potential of the entire block Project Site Details Location of the Block The NELP block AA-ONN-2001/2 in the state of Mizoram measuring 5340 sqkm was awarded to ONGC-IOC (80% and 20% PI) consortium with ONGC as Operator. After fulfillment of MWP in Phase-I & -II, ONGC entered into phase-iii w.e.f by relinquishing an area of 1345 sqkm as per PSC norms after retaining an area of 2660 sqkm. In current exploratory Phase-III, the Operator ONGC has to drill one well to fulfill MWP commitment. In addition to one MWP well, ONGC proposes to drill additional exploratory wells to assess hydrocarbon potentiality of the entire block. Elevation of the block varies from 400 m to 2000 m. Index Map is shown in Figure-1.1. The block coordinates are given in Table-1.1. Tentative well coordinates are as given in Table-1.2. VIMTA Labs Limited, Hyderabad C1-2

11 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction TABLE-1.1 BLOCK COORDINATES Sr. No ML Name Boundary Points Block Coordinates (WGS-84) Latitude Longitude 1 A B C D E NELP Block F AA-ONN-2001/2 G H I J K L F to G interstate boundary between Mizoram & Assam G to H interstate boundary between Mizoram & Tripura A to L interstate boundary between Mizoram & Manipur TABLE-1.2 TENTATIVE WELL LOCATIONS Sr. Proposed Latitude Longitude Nearest Village District No. Location 1 HOAC North of Medium Kolasib 2 HOAD South of Medium Kolasib The study area map showing the block location and exploratory drilling well locations are shown in Figure-1.2. Google map showing block area with well locations is given in Figure-1.3. The environmental setting of the block area falling in NELP Block area is given in Table-1.3 to Table-1.4. The exploratory drilling well marked on Topo map are shown in Figure-1.4 to Figure-1.5. VIMTA Labs Limited, Hyderabad C1-3

12 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction HOAC Well Location HOAD Well Location FIGURE-1.1 INDEX MAP VIMTA Labs Limited, Hyderabad C1-4

13 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction FIGURE-1.2 TOPOGRAPHIC MAP NELP BLOCK IN KOLASIB & MAMIT DISTRICT VIMTA Labs Limited, Hyderabad C1-5

14 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction FIGURE-1.3 GOOGLE MAP SHOWING WELL LOCATIONS IN NELP BLOCK VIMTA Labs Limited, Hyderabad C1-6

15 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction FIGURE-1.4 TOPOGRAPHIC MAP HOAC WELL -10 KM RADIUS VIMTA Labs Limited, Hyderabad C1-7

16 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction FIGURE-1.5 TOPOGRAPHIC MAP HOAD WELL -10 KM RADIUS VIMTA Labs Limited, Hyderabad C1-8

17 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction TABLE-1.3 ENVIRONMENTAL SETTING OF WELL HOAC (10 KM RADIUS) Sr. No. Particulars Details 1 Well HOAC Location Village North Medium District Kolasib State Mizoram 2 Well site Coordinates Latitude N Longitude E 3 Well Site Elevation above MSL 757 m amsl 4 Geographical location in toposheet 83 D/12 5 Nearest representative IMD station Agartala (139 km, WSW) 6 India Meteorological Dept. (IMD), Data Annual Mean Max Temp Annual Mean Min Temp Annual Average Rainfall Predominant wind direction Study Period Site specific Mean Max Temp 30.7 Mean Min Temp 9.2 Average Rainfall 13.0 Predominant wind direction 33.0 o C 10.3 o C mm S and SE followed by SW S followed by SE. Next predominant are SW & N 7 Present land use at the site Single crop rain fed agricultural land 8 Nearest highway NH-154 (0.6 km, SE) 9 Nearest railway station Bairabi R.S (5.8, WSW) 10 Nearest airport Lengpui (Aizwal 39 km, S) 11 Nearest river Tlawng River (6.0 km, WSW) 12 Nearest town Kolasib (8.5 km, NE) 13 Nearest major town with 2,00,000 Impal (147 km, NE) population 14 Villages within 1 km radius Pangbalkawn (1.0 km, NE) 15 Hills/valleys Nil 16 Nearest tourist place Nil 17 Archaeologically important places Nil 18 Protected areas as per Wildlife Protection Act,1972 (Tiger reserve, Nil Elephant reserve, Biospheres, National parks, Wildlife sanctuaries, community reserves and conservation reserves) 19 Reserved / Protected Forests Within Inner line forest reserve 20 Seismicity Zone-V as per IS 1983 (Part-1) 2002 Note: All distances mentioned above in () are aerial distances VIMTA Labs Limited, Hyderabad C1-9

18 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction TABLE-1.4 ENVIRONMENTAL SETTING OF WELL HOAD (10-KM RADIUS) Sr. No. Particulars Details 1 Well HOAD Location Village South medium District Kolasib State Mizoram 2 Well site Coordinates Latitude 24 o N longitude 92 o E 3 Well Site Elevation above MSL 400 m amsl 4 Geographical location in 83 D/12 toposheet 5 Nearest representative IMD Agartala (139 km, WSW) station 6 India Meteorological Dept. Annual Mean Max Temp (IMD), Data Annual Mean Min Temp Annual Average Rainfall Predominant wind direction Study Period - Site specific Mean Max Temp 30.7 Mean Min Temp 9.2 Average Rainfall 13.0 Predominant wind direction 33.0 o C 10.3 o C mm S and SE followed by SW S followed by SE. Next predominant are SW & N 7 Present land use at the site Single crop rain fed agricultural land 8 Nearest highway NH-154 (2.7 km, NW) 9 Nearest railway station Bairabi R.S (7.3 km, NW) 10 Nearest airport Lengpuri(Aizwal 34 km, S) 11 Nearest rivers Tuwng River (6.3 km, WSW) 12 Nearest town Kolasib (10.8 km, NNE) 13 Nearest major town with Impal (149 km, NE) 2,00,000 population 14 Villages within 1 km radius Nil 15 Hills/valleys Nil 16 Nearest tourist place Nil 17 Archaeologically important places Nil 18 Protected areas as per Wildlife Nil Protection Act,1972 (Tiger reserve, Elephant reserve, Biospheres, National parks, Wildlife sanctuaries, community reserves and conservation reserves) 19 Reserved / Protected Forests Within Inner line forest reserve 20 Seismicity Zone-V as per IS 1983 (Part-1) 2002 Note : All distances mentioned above in () are aerial distances VIMTA Labs Limited, Hyderabad C1-10

19 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction Importance of the Project Total crude oil import for FY was MMT almost same as the imports during FY ( MMT; increase of 0.1%). However, import of petroleum products (20.28 MMT) increased by 21 percent, mainly on account of increase in import of LPG (26%), MS (58%), HSD (35%), Bitumen (80%), and other products like - Aviation gas, Pet Coke (33%), etc. Petroleum products export declined for the first time in last 15 years; registering a decline of 6.2 percent mainly on account of decline in export of Naphtha, Fuel oil, Bitumen, etc. With total import (crude and petroleum products) combined with total products export of MMT translates to net import volume of 146 MMT for FY Net import bill for crude oil during FY was 6, billion (US$ billion) against 8, billion (US$ billion) during FY a decrease of 20.5 per cent in terms of the Indian Rupee and decrease of per cent in dollar value mainly on account of lower crude oil prices in the international market. Energy security has become one of the top three goals of the Indian Government. 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 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. ONGC is engaged in the exploration of oil & gas in the NELP Block. Discovery of hydrocarbons in this block will substantially improve the socio-economic conditions of the region. The proposed exploration 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 exploratory drilling in NELP block, ONGC has retained the services of M/s Vimta Labs Limited, Hyderabad to prepare 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 to prepare an Environmental Management Plan (EMP) for mitigating adverse impacts. Environmental baseline monitoring has been carried out during 15 th January 2016 to 8 th April 2016 representing partly winter and pre monsoon season and used to identify potential significant impacts. The scope of the present study is inline with the TOR as recommended by MoEF&CC. The scope of study broadly includes: VIMTA Labs Limited, Hyderabad C1-11

20 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction 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 exploratory drilling that are likely to have an impact on the environment; Predicting the impacts on the environment due to exploratory drilling; 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; To prepare an Environment Management Plan (EMP) outlining the measures for improving the environmental quality and scope for future drilling 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 Administrative and Legislative Background The principal Environmental Regulatory Agency in India is the Ministry of Environment and Forests (MoEF&CC), New Delhi. MoEF formulates environmental policies and accords environmental clearance for the projects. The applicable environmental standards for the project are given in Annexure- III Study Area for EIA The study area for the EIA is the entire NELP block. The total block area is considered as the study area Methodology of the Study Vimta Labs Limited, Hyderabad 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, Noise and Bio diversity 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. VIMTA Labs Limited, Hyderabad C1-12

21 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-1 Introduction Field studies have been conducted for a period of three months (15 th January 2016 to 8 th April 2016 representing partly winter and pre-monsoon season to determine existing conditions of various environmental attributes as outlined in Table-1.5. TABLE-1.5 ENVIRONMENTAL ATTRIBUTES AND FREQUENCY OF MONITORING Sr. No. Environmental Component Sampling Locations Sampling Parameters 1 Meteorology One central Temperature, location Wind Speed, Wind Direction, Relative Humidity, Cloud Cover, Rainfall 2 Ambient Air Quality 10 Locations PM2.5, PM10, SO2, NOx, VOC, THC CH4-HC, non CH4-HC, and CO Total Sampling Period one non monsoon season (Three months) Two consecutive days per week for one non - monsoon season Sampling Frequency Continuous hourly recording 24 hourly samples 3 Water Quality 4 Locations of As per IS: Grab sampling Once during surface water & 6 study period locations of Ground water 4 Noise Monitoring 10 Locations Sound Pressure Continuously for Once during Levels 24 hours study period 5 Soil Analysis 10 Locations in Soil profile, Composite Once during Existing ecological Chemical sample study period resources within constituents study area 6 Ecology 5 Terrestrial Flora and fauna Field Once in Ecological observations and study period Locations & 3 secondary Aquatic location sources within Existing ecological resources within study area 7 Demography and Total block area Demographic Based on District Census Socio-economic aspects profile Handbook (2011) 8 Land Use Total block area Trend of land use Based on District Census change for Handbook (2001) and satellite different categories images 9 Geology - Geological history Data collected from primary sources 10 Hydrology - Drainage area and pattern, nature of Based on data collected from secondary sources streams, aquifer characteristics, recharge and discharge rates. 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. The methodology of monitoring and analysis is given in Annexure-IV. VIMTA Labs Limited, Hyderabad C1-13

22 Chapter-2 Project Description 2.0 PROJECT DESCRIPTION 2.1 Introduction This chapter presents the project information including technical details of the proposed drilling 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 exploratory drilling operation involves drilling of holes through various subsurface layers (geological formations) to predetermined depth of potential hydrocarbon reserves that are identified through interpretation of seismic data. The typical flow of events in planning and executing an exploratory well drilling activity comprises of the following steps: Site selection & acquisition; Site preparation; Pre-drilling activities like mobilising and commissioning rig; Drilling activities; Well testing; Well site abandonment and suspension phase; and Well site restoration in case of non-discovery of hydrocarbons. Exploratory drilling is a temporary activity which lasts for about 4-5 months days for each well in the block. 2.3 Need for Exploratory Drilling ONGC proposes to drill 2 nos of exploratory wells at selected area through seismic survey to identify and establish hydrocarbon potential. As exploration within the basin is still in its early stages, each new penetration aids in determining the basins stratigraphic architecture. The objective of exploratory drilling is to more definitively ascertain the oil reserves in the block, which then can be progressed to the development phase. The locations will vary, depending on the progressive exploration drilling results. ONGC has identified two well locations HOAC and HOAD are included in present EIA study. 2.4 Project Location and Layout Details It is proposed to drill 2 nos of exploratory wells in the NELP Block of Kolasib district, Mizoram. The proposed exploratory well sites has been identified based on the study and interpretation of the stratigraphy and seismic data. Within the identified location, the actual well drilling sites will be located based on the following consideration: Located at a safe distance from the nearest village habitat; VIMTA Labs Limited, Hyderabad C2-1

23 Chapter-2 Project Description Safe distances from any radio transmitters so that the use of explosives, if required and detonators may proceed without the danger of external activation; Located at least m away from rivers and natural water bodies; Ensure natural drainage channels are avoided or drainage channels rerouted to ensure unhindered flow of rain / flood water. Where necessary adequate erosion control measures will be provided; and Located in a manner to avoid mature jungles and reserve forests. The block coordinates and tentative well locations falling in the NELP on-shore block in Kolasib and Mamit district, Mizoram are given in Table-2.1 and Table TABLE-2.1 BLOCK COORDINATES Sr. No ML Name Boundary Points Block Coordinates (WGS-84) Latitude Longitude 1 A B C D E NELP Block F AA-ONN-2001/2 G H I J K L F to G interstate boundary between Mizoram & Assam G to H interstate boundary between Mizoram & Tripura A to L interstate boundary between Mizoram & Manipur TABLE-2.2 TENTATIVE WELL LOCATIONS Sr. Proposed Location Tentative Well Coordinates (WGS-84) No Latitude Longitude 1 HOAC HOAD All practicable means shall be taken to minimize or avoid detrimental effects on the surrounding environment by virtue of the construction of the location or the operation of the drilling rig. The above locations have been fixed by ONGC so that least possible effect may be felt by the surrounding environment and habitation due to the proposed exploratory drilling activities. VIMTA Labs Limited, Hyderabad C2-2

24 Chapter-2 Project Description The exploratory well drilling is a short duration activity and after the well testing is completed, the drill site is restored to near original conditions 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 well site is dependent on the type of drilling equipment deployed which in turn is dictated by the planned depth of drilling. Minimum land required at each well site during drilling will be 125 m x 125 m, i.e., 1.56 ha. On an average, the land requirement at each well site, including site facilities and camp site is considered as ha. About 2.5 hectare land for each well will be acquired on lease. The typical layout of the well site with ancillary structures is provided in Figure-2.1. Each exploratory well drill site will require the following facilities: Portable office cabins / rest rooms (container type cubicles); Drilling rig foundation and celler; Foundation / Pits for ancillary equipments; 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 bunded area; Radio room; Storm water drainage system; Internal roads and fencing. The proposed drilling 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 exploratory drilling project is subject to drilling of 2 wells in an area of 2660 km 2 to establish the presence of hydrocarbon reserves. The estimated cost of the proposed exploration well drilling Rs. 100 Crores. The salient features of the project and magnitude of various resources required for the project is given in Table-2.3. VIMTA Labs Limited, Hyderabad C2-3

25 Chapter-2 Project Description Fire Pit Waste Pit ReserveTank 2 Chem/Hopper Platform ReserveTank 1 Choke Mani-fold Pipe Rack Mud Pump 1 Suction Tank 2 Desilter DesanderDegasser Shale Shaker Mud Pump 2 Trip Tank Rig Sub-Structure Generator Control Room Cat Walk Well 125 m Water Tank Workshop Water Tank Diesel Tank Tool Bin Koomey unit Mud Lab TP Room CM's Room Canteen Office TP/Company Man Office Rubber Store Store Security Cabin * Not to Scale 125 m FIGURE-2.1 TYPICAL LAYOUT OF WELL SITE VIMTA Labs Limited, Hyderabad C2-4

26 Chapter-2 Project Description TABLE-2.3 SALIENT FEATURES OF THE PROPOSED EXPLORATORY DRILLING IN NELP BLOCK OF MIZORAM Sr. No Features Details 1 Total block area in the NELP block of 2660 km 2 area in Kolasib and district Mamit district 2 Project Operator Oil and Natural Gas Corporation Limited (ONGC) 3 Proposed number of wells 2 exploratory drilling wells (in Kolasib district) 4 Depth of wells 4400 m (approximately) 5 Estimated project cost Total of Rs. 100 Crores 6 Duration of exploratory 4-5 months drilling at each well site 7 Land requirement at each The 2.5 hectare land for each well. Total well site including site Average ha facilities and camp site At each well site: about 1.56 ha Base Camp: 0.5 ha 8 Hole size and casing 17 ½ and 13 ⅜ 9 Water requirement at each drill site during drilling phase and water source 10 Drill mud requirement at each drill site 11 Drill cuttings generation at each drill site 12 Drilling Wastewater generation at each well site 13 Domestic wastewater generation at each well site 14 Power requirement for each well 15 Manpower requirement for each well Source: Project Report Resource Requirement for the Project Land Requirement 25 m 3 /day, for a short period of 4-5 months Source : Local water sources through tankers/ Contactors About 700 m 3 of water based drill mud for each well About 500 m 3 /well About 15 m 3 /day (will be treated before sending for solar evaporation in lined pit at drilling site) 8 m 3 /day (treated in septic tank, followed by soak pit) 2250 KVA (Drill site: 750 KVA X 3 Nos) 25 persons/shift of 12 hrs. in two shifts 2 exploratory locations have been identified and tentative well location details are presented in Table 2.2. Minimum land required at each well site during drilling will be 125 m x 125 m, i.e., ha. Land requirement for the base camp will be about 0.5 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 bringing back to its original status and adequate compensation as per the guidelines of local administration will be provided 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 m 3 /day. However, the drilling and VIMTA Labs Limited, Hyderabad C2-5

27 Chapter-2 Project Description domestic water requirement would depend on the time required to drill the well, which is primarily dependent on the proposed depth. Table-2.4 gives the water consumption for a typical drill site. TABLE-2.4 WATER REQUIREMENTS PER WELL SITE Particulars Drilling water requirement at drilling site Domestic water requirement Total Water Consumption (KLD) Water Requirement 20 m 3 /day 5 m 3 /day 25 m 3 /day The water requirement will be met from the local sources through water tankers. Suitable water transport arrangement will be made to transfer water for both drilling and domestic purposes Power Requirement The total power requirement at the drilling site and camp site will be 2250 KVA. The power requirement in the drilling site and the campsites will be catered through Diesel Generator (DG) sets. The power requirement will be met by 3 Nos of 750 KVA DG sets. Stand by DG set arrangement of 1 No of 750 KVA at drilling site will be made. The DG set details and fuel requirements is given in Table-2.5. TABLE-2.5 DETAILS OF DG SETS Location DG Capacity Operational Stand by Fuel Requirement Drilling site 750 KVA 3 1 HSD 5 KL /day Manpower Requirement The drill site construction would be done largely employing local labour. At each drill site construction, local employment will be generated for about 25/shift of 12 hrs in two shifts Drilling Mud Only water-based drilling mud will be used for the drilling of all wells. Estimation of quantity of drilling mud is nearly 700 m 3 for each well. 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 in exploratory drilling. The constituents of water based mud (WBM) are given in Table-2.6. The special additives and their functions in WBM are shown in Table-2.7. VIMTA Labs Limited, Hyderabad C2-6

28 Chapter-2 Project Description TABLE-2.6 CONSTITUENTS OF WATER BASED MUD (WBM) Sr. No 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 Chemicals TABLE-2.7 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. The composition and other mud parameters for different hole sections are given in Table-2.8. TABLE-2.8 COMPOSITION AND PARAMETERS OF WATER BASED DRILLING MUD Mud Parameters Details for Different Hole Sections Hole Section 17 ½ 12 ¼ 8 ½ Depth 350 m to 500 m 900 m to 1500 m 1500 m to 3700 m Mud Type Spud Mud PHPA Polymer PHPA Polymer Density (ppg) 8.6+/ ppg ppg Viscosity (sec /qt) > PV (cps) Alap Alap Alap YP (lbs / 100ft 2 ) rpm dial reading ph 8.8+/ VIMTA Labs Limited, Hyderabad C2-7

29 Chapter-2 Project Description Mud Parameters Details for Different Hole Sections Hole Section 17 ½ 12 ¼ 8 ½ Ca ++ (mg/l) <400 <400 <400 MBT (ppb) <10 Drilled Solids (%) <7 <7 <5 API Fluid Loss (cc) n/c <20 <2 Lower Fluid Loss (cc) casing point casing point casing point HPHT (cc) n/c 250 F 250 F Cl (mg/l) 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 proposed exploratory drilling activity of 2 wells in the NELP block area will be accomplished in phases. To accomplish the exploration, the operator will drill 2 numbers of exploratory wells to a depth of about 4400 m each well. The duration of various stages of the drilling project is given as under: The duration of construction works including site excavation, preparation and well pad construction is expected to last approximately days for each well site. The duration of drilling will range from 4-5 months, depending on the target well depth. Well testing operation will be done over a period of 2-3 days. Abandonment and restoration of the 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 4-5 months under normal conditions. Working hours during the drilling operation will be 24 hours per day, seven days per week with 12 hours per shift. 2.7 Technology and Drilling Process Description The activity involves drilling of the hole across various ground layers to a predetermined depth. ONGC proposes to charter a land drilling rig to achieve the desired above objective. Rig essentially comprises of a mast, a draw work, rotatory table, Kelly or top drive, mud pump engines and generators. The drilling rig is presented in Figure-2.2. VIMTA Labs Limited, Hyderabad C2-8

30 Chapter-2 Project Description FIGURE-2.2 DRILLING RIG VIMTA Labs Limited, Hyderabad C2-9

31 Chapter-2 Project Description Proposed Drilling Sequence The drilling operation involves simultaneous data logging of the stratigraphy. If sufficient evidence is found of well location having trapped hydrocarbons, a well test will be performed to establish the oil & gas flow potential of the various zones of interest. In case the well test yields encouraging results, further exploratory wells will be drilled at identified locations within the prospect to delineate the extent and quantum of the reserve. The drilling rig will be a land rig or Mobile Land Rig of a smaller capacity with a standard water or synthetic based drilling fluid treatment system. The choice of the rig would depend on the depth and the geological formations likely to be encountered. The well site once drilled will be temporarily suspended and the rig will be moved to next location. The drilling campaign shall continue till adequate results of the reservoir are collected for estimating the developmental activities. The details of the exploratory drilling operation are given in the following sections Drilling Phase Having completed the drill site preparation, drilling rig and associated equipment will be moved on to the location. This will be followed by a rig building process. This process involves assembling of various rig parts and equipment to drill a well. Once the drilling rig is assembled, thorough rig inspection will be carried out to check equipment working capability and quality standards including compliance to HSE requirements Drilling a Well Well spudding is the start of drilling activity. Top-hole section will be drilled to a desired depth based on well design. After drilling top-hole section, it will be cased with a pipe called Casing. Casing provides support to hole wall and secures hole section. Other than that it isolates problematic hole sections such as loss zones, shale sections, over pressurized formations etc. After running casing, space between hole wall and Casing (annulus) will be cemented. This process of drilling and casing the hole section continues until the final well depth (target) is achieved. Drilling 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. VIMTA Labs Limited, Hyderabad C2-10

32 Chapter-2 Project Description Proposed Hole Size / Casing Programme The exploratory wells will be of Slim Hole Design. The wells will be drilled vertically to different depths based on the target depth. Details of typical hole size and casing are given in Table-2.9. It is to be noted that the figures given in the table below are approximate and subject to change as the drilling proceeds. TABLE-2.9 HOLE SIZE AND CASING DETAILS Hole Size Casing Size Note Installed during civil work 24 to Conductor 17 1/2 13 3/8 Casing 12 1/4 9 5/8 Casing 8 ½ 7 Casing 6 5 Liner (Contingency) 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. 2.8 Details of Project Utilities Site Preparation On identification of the proposed drilling 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 loadbearing capacity to enable all construction and drilling operations to be executed safely Approach Roads The approach road to drill 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 VIMTA Labs Limited, Hyderabad C2-11

33 Chapter-2 Project Description constructed roads or to restore them back to original land use condition will depend on the requirements of the local authorities 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 drill site involves transportation of drilling rig in modules and erected by means of mobile cranes. The drill site equipment s are designed as modular / skid mounted type, which facilitates quick demobilization and remobilisation. The installation of the drill 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 drill site facilities are detailed below. Earthwork The exploratory drill 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. Surface Drainage Drilling 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 Mizoram Pollution Control Board (MPCB) 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 VIMTA Labs Limited, Hyderabad C2-12

34 Chapter-2 Project Description 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 liters/day 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 shall be designed based on the CPCB guidelines for Hazardous waste Storage. The waste oil will be collected and handed over to MPCB and MoEF&CC authorized waste oil recyclers at the end of the exploratory 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 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 would be about 30 x 33 x 5 2 Nos, 38 x 33 x 5 1 Nos, 23 x 20 x 5 1 Nos, and oil pit 3 x 3 x 4 1 Nos 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 drill site operations will be disposed off in a septic tank soak pit system. The septic tank will conform to the IS design VIMTA Labs Limited, Hyderabad C2-13

35 Chapter-2 Project Description 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 is 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. 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. VIMTA Labs Limited, Hyderabad C2-14

36 Chapter-2 Project Description FIGURE-2.3 DRILLING FLUID CIRCULATION SYSTEM AT TYPICAL RIG VIMTA Labs Limited, Hyderabad C2-15

37 Chapter-2 Project Description 2.9 Post Drilling Operations - Abandonment and Restoration 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 Restoration of Well Sites Decommissioning upon Abandonment 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. 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 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 VIMTA Labs Limited, Hyderabad C2-16

38 Chapter-2 Project Description 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. 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 drilling activities Sources of Pollution General The various types of pollution from the proposed exploratory drilling operations are: Wastewater Generation and Disposal; Air Emissions; Solid Waste Generation; 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 4-5 months at each of the well locations Wastewater Generation and Disposal Water will be required during the exploratory drilling phase for drilling fluid preparation and for domestic purposes. Thus, wastewater during this phase will comprise of drilling wastewater and domestic wastewater. Drilling sites and camps site will have an adequate drainage system so that all wastewater are contained and disposed as per the PCB Standards. Means will be provided to trap any escape of oil before it can leave the site. Surface drains will be adequately graded and 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 15 to 20 m 3 /day of wastewater is expected. All wastewater streams except sewage will be directed to a 1 mm HDPE lined pit. Wastewater collected in the pit will be clarified and treated in solar evaporation pond or packaged wastewater treatment plant for removal of oil and suspended solids to meet the regulatory discharge standards. VIMTA Labs Limited, Hyderabad C2-17

39 Chapter-2 Project Description Solids generated from the treatment plant will be collected, tested for hazardous contents and disposed to land once it is ensured that there are no hazardous contents. Produced water generation is not envisaged during the exploratory drilling phase. 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. The quantity of sewage generated at each drill site is expected to be around 4 m 3 /day Air Emissions During routine drilling operation, 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 drilling 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 D.G exhaust stack will be about 7.5 m (including the height of the trailer from the ground). Natural gas and traces of crude oil in 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 natural gas flaring and additionally particulates in case crude oil is flared. It is assumed that the occurrence SO2 in the flare gas would be in traces or negligible Solid Waste The drilling operations generate drill cuttings. The minor wastes include sanitary waste, domestic waste and waste oil from lubricating system 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 Drill cuttings Drilling cuttings are worn out rocks from subsurface formations that are generated during drilling operations. The drill cuttings are conveyed to the VIMTA Labs Limited, Hyderabad C2-18

40 Chapter-2 Project Description 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 treated. The clarified drill cuttings would then be dumped in a HDPE lined pit. Once the drill cuttings are dried it will be further treated and disposed through land farming by applying oil degrading bacteria, native soil and nutrients. Bioremediation and land farming are considered as a good treatment options which are recognised by MoEF as per MoEF guidelines for disposal of Drill Cutting / Drilling Mud for onshore drilling activities (G.S.R. 546/E) dated Waste Pit details Typical sectional view of the drill cutting and drilling mud collection pit is presented in Figure-2.4. The storage pit will be constructed as per the method and specification of CPCB/MPCB. The pit shall consist of following layers commencing from the bottom; Compacted sub-base and side slopes comprising of clay or amended soil layer of 300 mm compacted thickness; Synthetic liner (HDPE / geo-membrane) of a minimum of 1.5 mm thick; and The drill cuttings are dewatered to reduce the amount of liquid fraction carry over. The liquid fraction of the drilling mud is recycled and excess fluid stored in the lined pits. The cuttings and mud waste are stored in lined pits and solar evaporated and covered with layer of local soil. The liner is tucked into the natural ground to form a continuous layer. All joints are seam welded to ensure the cover is continuous over the surface of the pit material. The pit is filled back with natural soil and locally available clay layer is placed at the upper most layer (top surface). The top surface is cambered with 2 3% slope to drain away the rain water from the pit location. VIMTA Labs Limited, Hyderabad C2-19

41 Chapter-2 Project Description FIGURE-2.4 TYPICAL SECTION VIEW OF DRILLING CUT AND DRILL MUD COLLECTION PIT VIMTA Labs Limited, Hyderabad C2-20

42 Chapter-2 Project Description 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 liters/month of used / spent oil would be generated from a drilling operation. Stored waste oil would be disposed off to Mizoram State PCB & MoEF registered used / spent oil recyclers Summary of Waste Generation Quantities and Treatment and disposal Method The quantum of wastes that would be generated from each well depends upon its target depth and duration of testing 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. The potential source of heavy metal concentration in the drilling mud is primarily from the barite used in the mud formulation. Presence of heavy metal in drill cuttings is attributed to lithological characteristics of subsurface layers. Drill cuttings and mud would thus also be analyzed for heavy metal concentrations before disposal 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 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. VIMTA Labs Limited, Hyderabad C2-21

43 b) Skills Environmental Impact Assessment Report for Proposed Exploratory Drilling of 2 Chapter-2 Project Description 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 drill 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. 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 than 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. VIMTA Labs Limited, Hyderabad C2-22

44 Chapter-2 Project Description 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. VIMTA Labs Limited, Hyderabad C2-23

45 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 3.0 BASELINE ENVIRONMENTAL STATUS 3.1 Introduction This chapter illustrates the description of the existing environmental status of the study area with reference to the prominent environmental attributes. The study area (10-km radius) covers 2 wells in existing NELP Block AA-ONN- 2001/2, Kolasib & Mamit District, Mizoram. The entire block area considered for the study, description of biological environment and Human environment such as environmental settings, demography & socio-economics, land-use/land cover, ecology & biodiversity have been carried out during study period. However, as a universally accepted methodology of EIA studies, physical environmental attributes such as Ambient Air Quality, Water Quality, Soil Quality, Noise Levels, Physiography, Hydrology, Odour, Solid Waste Generation have been studied at selective locations representing various land uses such as industrial, rural/residential, commercial and sensitive locations including the densely populated areas, agricultural lands, forest lands and other ecologically sensitive areas, if any falling within block area. The existing environmental setting is considered to know the baseline environmental conditions, which are described with respect to climate, hydrogeological aspects, atmospheric conditions, water quality, soil quality, ecology, land use and socio-economic profiles of people. The baseline studies were conducted covering partly winter and partly pre-mosoon season starting from 15 th January 2016 to 8 th April This Report incorporates the baseline data monitored for winter season and secondary data collected from various Government and Semi-Government organizations. 3.2 Geology and Hydrogeology Physiography (Kolasib and Mamit Districts) Physiographically, the terrain is mountainous with prominent relief. Hill ranges are trending in the north-south direction. Parallel to sub parallel anticlinal hill ranges, synclinal narrow valleys form deep gorges. Basically these are structural hills. The process of denudation and weathering is still continuing in response to various natural forces. One of the dominant forces of formation of such landforms is exerted by running water. Based upon lithology, relief, drainage, and structural pattern, the district has been divided into two major units viz denudostructural hills and valleys. Denudo-structural Hills Major portion of the district is occupied by denudo- structural hills which are predominantly argillaceous comprising shale, siltstone and mudstone, fine grained and compact sandstone with occasional limestone. The processes of denudation have not yet obliterated the structural features such as dip facets and strike trend; anticline and syncline. This major form has been further divided as follows: VIMTA Labs Limited, Hyderabad C3-1

46 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Low Linear Ridges These are low elevated hills and occupy outer flank of structural folds. They have gentle to moderate slopes and possess gully erosion. The main drainage system is controlled by strike of the formations and shows slight meandering pattern. The main rock types represent a mixture of arenaceous as well as argillaceous assemblages, comprising shale and fine to medium grained, friable sandstone. Moderate Linear Ridge Moderate linear ridges occupy about 90% of the district. The main constituents are hard and compact sandstone, shale and siltstone, alterations of Bhuban Formation. The ridges show serrated top and hogback pattern, which are highly dissected and separated by intervening V shaped narrow valleys. Valleys in Kolasib District The valleys have limited aerial extend and occur mostly in the North, Northwest and a portion of south part of the district adjacent to Hailakandi and Cackar districts of Assam. Valleys in Mamit District The valleys have limited aerial extend trending North-South direction. Linear rolling valley Kolasib District These valleys are found in the structural depressions in between low linear ridges of fine to medium grained, friable sandstone with subordinate shale of Bhuban group of rocks and siltstone, shale, and mudstone with subordinate sandstone of Bokabil group of rocks. Linear rolling valley Mamit District These valleys are found in the structural depressions in between low linear ridges of fine to medium grained, friable sandstone with subordinate shale of Bhuban group of rocks Geology of Kolasib District Geologically, the district is occupied by shale, siltstone, and sandstone of Barail Formation of Oligocene age and Surma Formation of Miocene age. Geology of Mamit District Geologically, the district is occupied by shale, siltstone, and sandstone of Barail Formation of Oligocene age and Surma and Tipam formation of Miocene age. Geological setting of the area falling in AA-ONN-2001/2 Block Geological mapping carried out by ONGC has identified four structures in the block viz Sentet Anticline, Aizawl Anticline, Teidukhan Anticline & Hachek VIMTA Labs Limited, Hyderabad C3-2

47 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Anticline. Gas discovery has been made in well HO-01 from Lower Bhuban play in Sentet cross faulted plunge area Rainfall and Climate (Kolasib and Mamit Districts) The climate of the district is characterized by tropical humid climate with cool summers and cold winters. Winter temperatures vary between 11ºC and 13º C in general. The winter season is however, without snow. The normal annual rainfall is 2,216 mm and average annual rainfall is 2,794 mm. the rainfall is due to the monsoons from early May to late September Drainage of Kolasib District The major drainages include Serlui, Tuichhuahen and Tuirial Rivers. Numbers of perennial streams flow through the district from north to south. Drainage of Mamit District The major drainages include Tuirial River flowing to the South. Numbers of perennial streams flow through the district from north to south Soil types (Kolasib and Mamit Districts) The soils of the districts, in general, have been derived from parent rock such as ferruginous sandstone, shale, alluvial and colluvial materials. In general, the soil formations have been categorized into following groups: Hills It includes colluvial soil, formed along the steep sided slopes because of accumulation of soil forming materials on slope surface. Valleys Soils occur as a mixture of colluvial and alluvial materials. It is restricted to the rolling valleys along the river cources. Terraces These are the remnants of deposits of cobbles and pebbles Hydrogeology The hydrogeological studies to understand the local geology, geomorphic features, drainage network, aquifer characteristics and yield of water. Accordingly, various components controlling the hydrogeological regime. Hydrogeology map of Kolasib and Mamit districts is given in Figure & VIMTA Labs Limited, Hyderabad C3-3

48 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Hydrogeologically, the entire area of Kolasib and Mamit districts is occupied by semi-consolidated formations of denudostructural hills belonging to Barail Formation of Oligocene age and Surma and Tipam Formation of Miocene age with limited aerial extent of linear rolling valleys adjacent to Assam. The low linear ridges are characterized by low permeability and infiltration capacity. It acts as run off zone. The moderate linear ridges, which occupy the major portion of the district, comprise hard and compact sandstone, shale, siltstones and alternations of Bairal and Surma Group of rocks. This unit is also characterized by very low permeability and infiltration capacity that acts as run off zone. Ground water potential is low. The linear rolling valleys with limited aerial extend are underlain by shale, sandstone and siltstone alternations. No ground water abstraction structures are noticed in the valley. However, during earlier field investigation by CGWB, occurrences of small pond like structures with very shallow water level (2.0 m bgl) had been reported. As such, shallow ground water structures may be feasible in suitable locations of the valley portions. Occurrence of ground water (Kolasib and Mamit Districts) Ground water systems are a result of the complex combination of different lithological and structural types within an area that together constitute an aquifer within which ground water accumulates and moves. Rather than describing individual lithologies and their tendencies to form aquifers or otherwise, it is useful to describe the ground water as one continuous across various lithological types (Kulkarni and Deolankar, 1995). In general, the terrain is tectonically young and immature. The occurrence of ground water in such a terrain is mainly restricted to weak zones such as fractures, lineaments and weathered residuum. These tectonic elements create seepage conduits, which are sources of springs. These springs are utilized as the main source of water supply to the populace. The existing water supply for drinking purposes is mainly from those springs tapped through gravity drainage. A number of springs were inventoried during earlier field investigations. All the springs are fractures and joints oriented. A large number of springs are perennial. In general, discharges of the springs are meager in high altitudes which progressively increase down slope. Discharges of the spring vary between 3000 and 20,000 litres per day during the period from January to March, which is generally dry period. VIMTA Labs Limited, Hyderabad C3-4

49 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status FIGURE HYDROGEOLOGY MAP OF KOLASIB DISTRICT VIMTA Labs Limited, Hyderabad C3-5

50 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status FIGURE HYDROGEOLOGY MAP OF MAMIT DISTRICT VIMTA Labs Limited, Hyderabad C3-6

51 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Ground Water Resources Ground Water Recharge 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 dynamic groundwater resources of Kolasib and Mamit Districts has been estimated jointly by CGWB and SWID. Govt of Mizoram, following the norms laid down by GEC-1997 methodology and projected as on The ground water resources of the districts is given in Table TABLE THE DYNAMIC GROUNDWATER RESOURCES AS ON Quantity (Ham) Sr.No Particulars Kolasib Mamit 1 Total Annual Replenishable Ground Water Resources 2 Natural Discharge during Non-Monsoon Period 3 Net Annual Ground Water Availability Total Annual Ground Water Draft Projected demand for Domestic and Industrial uses upto Net Ground Water Availability for Future Irrigation use 7 Stage of Ground Water Development (%) 2.07 ( Safe ) 2.41 ( Safe ) Source: Dynamic Ground Water Resources of India-July 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 Objectives The objectives of land use studies are: To determine the present land use pattern; To analyze the impacts on land use due to drilling activities in the study area; and To give recommendations for optimizing the future land use pattern vis-a-vis growth of drilling activities in the study area and its associated impacts. VIMTA Labs Limited, Hyderabad C3-7

52 3.3.2 Methodology Environmental Impact Assessment Report for Proposed Exploratory Drilling of 2 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status For the study of land use, literature review of various secondary sources such as District Census Handbooks, regional maps regarding topography, zoning settlement, industry, forest etc., were taken. The data was collected from various sources like District Census Handbook, Revenue records, state and central government offices and Survey of India (SOI) Topo-sheets and also through primary field surveys Land Use Based on Satellite Imagery Present land use based on remote sensing satellite imageries were collected and interpreted for the block area for analyzing the land use pattern of the study area. Based on the satellite data, land use/ land cover maps have been prepared. Land use/land Cover Classification System The present land use / land cover maps were prepared based on the classification system of National standards. For explanation for each of the land use category the details as given in Table are considered. TABLE LAND USE/LAND COVER CLASSIFICATION SYSTEM Sr. No. Level-1 Level-2 1 Built-up Land Town/cities Villages Institution/industry/godown etc Plotted area/layout 2 Agriculture Land Crop land Plantations Fallow 3 Forest Evergreen/semi evergreen Deciduous Forest plantation 4 Wastelands Rocky/stony waste Land with /without shrubs Saline/sandy & marshy/swampy 5 Water Bodies River/stream Lake/reservoir/tanks 6 Others Orchard/Other plantation Shifting cultivation Salt pans, snow covered/glacial Barren/vacant land Data Requirements IRS Resourcesat-2 of 5m resolution (LISS-IV) FX was acquired for 16 th January & 28 th February, 2015 and was used for the mapping and interpretation. Besides, other collateral data as available in the form of maps, charts, census records, other reports and especially topographical survey of India maps are used. In VIMTA Labs Limited, Hyderabad C3-8

53 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status addition to this, ground truth survey was also conducted to verify and confirm the ground features. Methodology The methodology adopted for preparation of land use/ land cover thematic map is monoscopic visual interpretation of geocoded scenes of IRS Resourcesat-2 (LISS3) and field observations are taken. The various steps involved in the study are preparatory field work, field survey and post field work. Pre-field Interpretation of Satellite Data The False Colour Composite (FCC) of IRS Resourcesat-2 satellite data are used for pre-field interpretation work. Taking the help of topo sheets, geology, geomorphology and by using the image elements the features are identified and delineated the boundaries roughly. Each feature is identified on image by their image elements like tone, texture, colour, shape, size, pattern and association. A tentative legend in terms of land cover and land use, physiography and erosion was formulated. The sample areas for field check are selected covering all the physiography, land use / land cover feature cum image characteristics. Software s used a) ERDAS Imagine for image processing/rectification/geocoding; b) AutoCAD for data preparation after visual interpretation of the image; and c) Arc View for image/landuse presentation. Ground Truth Collection Both toposheets and imagery were taken for field verification and a transverse plan using existing road network was made to cover as many representative sample areas as possible to observe the broad land use features and to adjust the sample areas according to field conditions. Detailed field observations and investigations were carried out and noted the landuse features on the imagery. Post Field Work The base maps of the study area were prepared, with the help of survey of india toposheet. Preliminary interpreted land use and the land cover features boundaries from IRS false colour composite were modified in light of field information and the final thematic details were transferred onto the base maps. The final interpreted and classified thematic map was catrographed. The cartographic map was coloured with standard colour coding and detailed description of feature with standard symbols. All the classes noted and marked by the standard legend on the map. Final Output The final output would be the landuse/land cover map and numerals were given different colour code for each category as shown in map. Area estimation of all features of land use/land cover categories was noted. The satellite imagery and VIMTA Labs Limited, Hyderabad C3-9

54 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status land use pattern is shown in Figure and Figure The details of the land use in block area are given in Table Digital elevation model of the study area is shown in Figure TABLE LAND USE BREAK UP OF THE STUDY AREA Sr. No. Landuse Area (Sq. Km) % 1 Built Up Land A. Settlements / Air Port Waterbodies A. Reservoir / River etc Crop Land A. Crop land Wastelands A. Land with scrub B. Land without scrub C. Mining area TOTAL Observations The land use pattern of the study area indicates built-up land of 4.9%, land under agriculture is about 4.6 %, waste land is about 80.1% and water bodies contribute about 10.4% in the study area. VIMTA Labs Limited, Hyderabad C3-10

55 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status FIGURE SATELLITE IMAGERY OF THE BLOCK AREA VIMTA Labs Limited, Hyderabad C3-11

56 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status FIGURE LAND USE PATTERN BASED ON SATELLITE DATA VIMTA Labs Limited, Hyderabad C3-12

57 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 3.4 Soil Characteristics For studying soil profile of the region, sampling locations were selected to assess the existing soil characteristics in and around the exploratory drilling area representing various land use conditions. The physical, chemical and heavy metal concentrations were determined. The samples were collected by ramming a corecutter into the soil upto a depth of 90 cm. A total of 10 numbers of samples within the study area were collected and analyzed. The details of the soil sampling locations are given in Table and are shown in Figure The soil sampling photographs are shown in Figure The sampling has been carried out once in the study period representing partly winter and partly premonsoon season (15 th January 2016 to 8 th April 2016). TABLE DETAILS OF SOIL SAMPLING LOCATIONS Sampling Station Location Well location S1 Bilkhawthir - S2 Kolasib - S3 Bairabi Near HOAC, HOAD S4 Suarhlip Near BRBAA S5 Sethawn - S6 Zamuang - S7 Vawngawn - S8 Mualvum - S9 Mamit - S10 Lengpui - The soil quality at all the locations during the study period is given in Table The results are compared with standard classification given in Table Baseline Soil Status It has been observed that the texture of soil is mostly clay type in the study area. The ph of the soil indicating that is neutral to moderately alkaline in nature. The Electrical conductivity was recorded as µs/cm to µs/cm. Minimum concentration was observed at S3 and maximum concentration at S7 during the study period. The Organic Carbon content in the study area observed as 0.31 % to 0.62 %, which the soil falls under on average sufficient to more than sufficient category. Available potassium was observed as minimum 86.6 Kg/ha at S6 and maximum observed as Kg/ha at at S7 indicating that the soil falls under very lees to less. Available Nitrogen was observed as 31.5 Kg/ha to 69.7 kg/ha. Minimum concentration is observed at site S3 and the maximum observed concentration observed at S8 locations. Based on the above values the soil falls under very less to less category. Available phosphorous was observed as 13.5 kg/ha to 88.6 kg/ha in the study region. The minimum value observed at S4 location and the maximum was observed at S7 location. It shows the soil falls under very less to more than sufficient category. VIMTA Labs Limited, Hyderabad C3-13

58 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status FIGURE SOIL SAMPLING LOCATIONS VIMTA Labs Limited, Hyderabad C3-14

59 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Soil sampling at Bairabi Soil sampling at Suarhlip FIGURE SOIL SAMPLING PHOTOGRAPHS VIMTA Labs Limited, Hyderabad C3-15

60 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status TABLE SOIL ANALYSIS RESULTS Sr.No. Location Unit S1 S2 S3 S4 S5 S6 S7 S8 S9 S10 1 ph (1:5 Aq. Extraction) Conductivity (1:5 Aq. µs/cm Extraction) 3 Texture -- Clay Sandy Clay Sandy Clay Clay Clay Sandy Clay Clay Clay Loam Clay Clay 4 Sand % Silt % Clay % Bulk Density g/cc Exchangeable Calcium as Ca mg/kg Exchangeable Magnesium as Mg mg/kg Exchangeable Sodium as Na mg/kg Sodium Absorption Ratio Available Nitrogen as N Kg/ha Available Phosphorous as P Kg/ha Available Potassium as K Kg/ha Organic Carbon % Organic Matter % Water soluble chloride as Cl mg/kg Water soluble sulphates as SO4 mg/kg Aluminium % Total Iron % Manganese mg/kg Boron mg/kg Zinc mg/kg VIMTA Labs Limited, Hyderabad C3-16

61 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status TABLE STANDARD SOIL CLASSIFICATION Sr. No. Soil Test Classification 1 ph <4.5 Extremely acidic Very strongly acidic Moderately acidic Slightly acidic Neutral Slightly alkaline Moderately alkaline Strongly alkaline >9.00 Very strongly alkaline 2 Salinity Electrical Conductivity (ppm) (1 ppm =640mho/cm) Upto 1.00 Average harmful to germination Harmful to crops (sensitive to salts) 3 Organic Carbon Upto 0.20: Very less : Less : Medium, : On an avg. sufficient : Sufficient >1.00 : More than sufficient 4 Nitrogen (Kg/ha) Upto 50 Very less Less Good Better >300 Sufficient 5 Phosphorus (Kg/ha) Upto 15 Very less Less Medium, On an avg. sufficient Sufficient >80 More than sufficient 6 Potash (Kg/ha) Very less Less Medium Average Better >360 More than sufficient Source: Hand Book of Agriculture, ICAR, New Delhi 3.5 Meteorology The meteorological data recorded during the monitoring period is very useful for proper interpretation of the baseline information as well as for input prediction models for air quality dispersion. Historical data on meteorological parameters will also play an important role in identifying the general meteorological regime of the region. The year may broadly be divided into four seasons: Winter season : December to February Pre-monsoon season : March to May Monsoon season : June to September Post-monsoon season : October to November VIMTA Labs Limited, Hyderabad C3-17

62 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Methodology The methodology adopted for monitoring the surface meteorological conditions observations is as per the standard norms laid down by Bureau of Indian Standards (IS: 8829) and India Meteorological Department (IMD). On-site monitoring was undertaken for various meteorological variables in order to generate the site-specific data. Data was collected every hour continuously from 15 th January 2016 to 8 th April Methodology of Data Generation A Central Monitoring Station (CMS) equipped with continuous monitoring equipment was installed on top of a building at a height of 6 m above ground level to record wind speed, direction, relative humidity and temperature. The meteorological monitoring station was located in such a way that it is free from any obstructions and as per the guidelines specified under IS: Cloud cover was recorded by visual observation. Rainfall was monitored by using rain gauge. The continuous recording meteorological instrument of Dynalab, Pune (Model No.WDL 1002) has been used for recording the met data. The sensitivity of the equipment is as given in Table TABLE SENSITIVITY OF METEOROLOGY MONITORING EQUIPMENT Sr. No. Sensor Sensitivity 1 Wind speed Sensor ± 0.02 m/s 2 Wind direction Sensor ± 3 degrees 3 Temperature Sensor ± 0.2 o C Sources of Information Secondary information on meteorological conditions has been collected from the nearest IMD station at Agartala. The available meteorological data of IMD, Agartala station has been collected for the past 10 years and analyzed Presentation of Data Meteorological Data Recorded at IMD, Agartala The meteorological data is collected from IMD - Agartala, which is the nearest IMD station to the project site. The data collected from IMD includes wind speed, wind direction (recorded in sixteen directions), temperature, relative humidity, atmospheric pressure; rainfall and cloud cover over a period of past 10 years. The monthly maximum, minimum and average values are collected for all the parameters except wind speed and direction. All these parameters are recorded twice a day viz at 0830 and 1730 hours. The collected data is tabulated in Table VIMTA Labs Limited, Hyderabad C3-18

63 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Meteorological Data Generated at site The meteorological parameters are recorded on hourly basis during the study period from 15 th January 2016 to 8 th April 2016 and the parameters recorded at site include wind speed, wind direction (from 0 to 360 degrees), temperature, relative humidity, atmospheric pressure, rainfall and cloud cover Synthesis of Data on Climatic Conditions Analysis of the Data Recorded at IMD - Agartala 1] Temperature The winter season starts from December and continues till the end of February. January is the coolest month with the mean daily maximum temperature at C and the mean daily minimum temperature at C. Both the night and day temperatures increase rapidly during the onset of the pre-monsoon season from March to May. During pre-monsoon season, the mean maximum temperature (April) was observed to be C with the mean minimum temperature at C. The mean maximum temperature in the monsoon season was observed to be C in the month of June whereas the mean minimum temperature was observed to be C in the month of September. By the end of August, the day temperatures increase slightly, with the mean maximum temperature at C and the night temperature decreases with the mean minimum temperature at C. The monthly variations of temperature are presented in Table ] Relative Humidity The air is generally humid in this region during the monsoon season when the relative humidity was observed to be 83% with a maximum and a minimum of 79%. Generally, the weather during other seasons was observed to be dry. The monthly variations in the relative humidity are presented in Table ] Atmospheric Pressure The maximum pressure observed was mb occurring during the winter season, in the month of January. The minimum pressure observed was mb occurring during the month of June in the monsoon season. It can be seen from the data that not much variations are observed in the average atmospheric pressure levels. The pressure levels are found to be fairly consistent over the region. The monthly variations in the pressure levels are presented in Table TABLE CLIMATOLOGICAL DATA STATION: IMD, AGARTALA Month Atmospheric Pressure Temperature Relative Humidity (mb) ( 0 C) (%) Rainfall Mean Max Mean Min Mean Max Mean Min Mean Max Mean Min (mm) January February March VIMTA Labs Limited, Hyderabad C3-19

64 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Month Atmospheric Pressure Temperature Relative Humidity (mb) ( 0 C) (%) Rainfall Mean Max Mean Min Mean Max Mean Min Mean Max Mean Min (mm) April May June July August September October November December Total Rainfall ] Rainfall The average annual rainfall based on the 10 year IMD data, was observed to be 2,121.6 mm. The monsoon sets in the month of June and continues till September and sometime extends upto mid October. The maximum amount of rainfall (382.2 mm) occurs in the month of May. The maximum number of rainy days was observed in the month of July. Monthly variations in the rainfall are given in Table ) Wind Speed/Direction Generally, light to moderate winds prevails throughout the year. Winds were light and moderate particularly during the morning hours. While during the afternoon hours the winds were stronger. The season wise discussion of the respective wind Pattern is given as below: A) Wind Pattern during Pre-Monsoon Season 0830 Hours: A review of the wind rose diagram shows that predominant winds are mostly from S and SE directions followed by SW direction (Figure-3.5.1). Calm conditions prevailed for 12.7% of the total time Hours: A review of the wind rose diagram shows that predominant winds are mostly from S and SW directions followed by SE direction (Figure-3.5.1). Calm conditions prevailed for 29.1% of the total time. B) Wind Pattern during Monsoon Season 0830 Hours: A review of the wind rose diagram shows that predominant winds are mostly from S and SE directions followed by SSE direction (Figure-3.5.2). Calm conditions prevailed for 14.1% of the total time. VIMTA Labs Limited, Hyderabad C3-20

65 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 1730 Hours: A review of the wind rose diagram shows that predominant winds are mostly from S and SE directions followed by SSE direction (Figure-3.5.2). Calm conditions prevailed for 29.7% of the total time. C) Wind Pattern during Post-Monsoon Season 0830 Hours: A review of the wind rose diagram shows that predominant winds are mostly from NE and N directions followed by S direction (Figure-3.5.3). Calm conditions prevailed for 40.5% of the total time Hours: A review of the wind rose diagram shows that predominant winds are mostly from S and N directions followed by NW direction (Figure-3.5.3). Calm conditions prevailed for 83.5% of the total time. D) Wind Pattern during Winter Season 0830 Hours: A review of the wind rose diagram shows that predominant winds are mostly from S and N directions followed by SE direction (Figure-3.5.4). Calm conditions prevailed for 54.4% of the total time Hours: A review of the wind rose diagram shows that predominant winds are mostly from N and SW directions followed by NW direction (Figure-3.5.4). Calm conditions prevailed for 81.3% of the total time. E) Annual Wind Pattern 0830 Hours: A review of the wind rose diagram shows that predominant winds are mostly from S and SE directions followed by N direction (Figure-3.5.5). Calm conditions prevailed for 30.6% of the total time Hours: A review of the wind rose diagram shows that predominant winds are mostly from S and SE directions followed by SW direction (Figure-3.5.5). Calm conditions prevailed for 55.9% of the total time. VIMTA Labs Limited, Hyderabad C3-21

66 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 2.7% NW 0.3% WNW 2.0% W C-12.7% E 7.0% 0% WSW ENE 0% 7.3% SW 0% NNW N 4.0% SSE 5.0% 2.2% SSW NNE 0% NE 5.6% ESE 0.3% SE 14.3% 08:30 Hrs PRE MONSOON 36.6% S 10.2% SW 1.9% NW 0% WNW N 3.6% 0% NNW SSE 2.6% 3.3% W C-29.1% 0% WSW 2.2% SSW NNE 0% NE 2.0% ENE 0% E 2.8% ESE 0% SE 9.5% SPEED CALM 1 SCALE % 19 >19 Km/hr 32.8% S 17:30 Hrs PRE MONSOON FIGURE IMD AGARTALA-PRE MONSOON SEASON VIMTA Labs Limited, Hyderabad C3-22

67 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 0% NW 0.5% WNW 0% WSW 3.2% SW 0% NNW N 1.7% 0.5% W C-14.1% 0.5% SSW NNE 0.2% NE 1.5% ENE 0% ESE 0.5% SSE 9.0% E 8.0% SE 24.2% 36.1% S 08:30 Hrs MONSOON 1.5% NW 0% WNW 4.2% SW 0.3% NNW 0.3% WSW 2.0% SSW N 2.7% 2.0% W C-29.7% NNE 0.3% SSE 5.0% NE 1.5% ENE 0% E 2.0% ESE 0.3% SE 11.7% 17:30 Hrs MONSOON SPEED CALM 1 SCALE % 19 >19 Km/hr 36.5% S FIGURE IMD AGARTALA-MONSOON SEASON VIMTA Labs Limited, Hyderabad C3-23

68 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 3.0% NW 0% WNW 3.0% SW 1.0% SSW 11.5% S N 11.5% SSE 2.0% NNE 1.5% ENE 0% NE 12.5% 2.5% W C-40.5% E 5.5% 0% WSW 0% NNW ESE 1.0% SE 4.5% 08:30 Hrs POST MONSOON 2.0% NW 0% WNW 0.5% NNW 0% WSW 1.0% SW 0% SSW N 4.0% 0.5% W C-83.5% 4.5% S NNE 0.5% SSE 0.5% NE 1.0% ENE 0% E 1.0% ESE 0% SE 1.0% 17:30 Hrs POST MONSOON SCALE 5% SPEED CALM >19 Km/hr FIGURE IMD AGARTALA-POST MONSOON SEASON VIMTA Labs Limited, Hyderabad C3-24

69 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 4.0% NW 0% WNW 4.3% SW 1.3% NNW N 9.3% 2.0% W C-54.4% 0.3% WSW SSE 0.6% 0.3% SSW NNE 1.3% NE 3.6% ENE 0.3% E 2.9% ESE 0.3% SE 5.6% 9.5% S 08:30 Hrs WINTER 3.0% NW 0.3% WNW 0.7% NNW 0.3% WSW 3.3% SW 0% SSW N 5.3% 1.9% W C-81.3% 2.3% S SSE 0% NNE 0% NE 1.0% ENE 0% E 0% ESE 0% SE 0.6% 17:30 Hrs WINTER SCALE 5% SPEED CALM >19 Km/hr FIGURE IMD AGARTALA-WINTER SEASON VIMTA Labs Limited, Hyderabad C3-25

70 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 2.5% NW 0.1% WNW 4.5% SW 0% NNW N 6.6% 1.8% W C-30.6% 0.1% WSW 0.9% SSW NNE 0.9% SSE 4.1% NE 5.7% ENE 0.2% ESE 0.5% E 5.9% SE 12.2% 23.4% S 08:30 Hrs ANNUAL 2.1% NW 4.8% SW 0.4% NNW 0.1% WNW 0.2% WSW 1.1% SSW N 3.9% 1.9% W C-55.9% NNE 0.2% SSE 2.0% NE 1.2% ENE 0% E 1.4% ESE 0.1% SE 5.7% SPEED CALM 1 SCALE % 19 >19 Km/hr 19.0% S 17:30 Hrs ANNUAL FIGURE IMD AGARTALA-ANNUAL WINDROSE VIMTA Labs Limited, Hyderabad C3-26

71 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Observations on Primary Data The site specific data is presented in Table and discussed below: TABLE SUMMARY OF THE METEOROLOGICAL DATA GENERATED AT SITE Month Temperature ( 0 C) Relative Humidity (%) Rainfall (mm) Max. Min. Max. Min. Jan Feb Mar Apr ] Temperature Maximum temperature of 30.7 o C and minimum temperature of C was recorded during the study period. 2] Relative Humidity During the period of observation the Relative Humidity recorded ranged from 79 % to 54 %. 3] Rainfall The 15.3 mm rainfall was observed during the study period. 5] Wind Speed/Direction The wind rose for the study period representing winter season is shown in Figure A review of the wind rose diagram shows that predominant winds are mostly from N followed by S. Next predominants are NW & SE followed by SW direction. Calm conditions prevailed for 61.2 % of the total time. VIMTA Labs Limited, Hyderabad C3-27

72 S 7.1% Environmental Impact Assessment Report for Proposed Exploratory Drilling of 2 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status N 8.3% NW 4.2% WNW 0.9% NNE 1.1% NE 2.6% ENE 0.6% W 2.4% C-61.2% E 1.3% SW 3.9% NNW 0.4% WSW 0.5% SSW 0.4% SSE 0.7% ESE 0.2% SE 4.2% SCALE 5% SPEED CALM >19 Km/hr FIGURE SITE SPECIFIC WINDROSE-WINTER SEASON VIMTA Labs Limited, Hyderabad C3-28

73 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 3.6 Ambient Air Quality The ambient air quality with respect to the study zone around the proposed block forms the baseline information. The prime objective of the baseline air quality study was to assess the existing air quality of the area. This will also be useful for assessing the conformity to standards of the ambient air quality during the operation of proposed drilling project. This section describes the selection of sampling locations, methodology adopted for sampling, analytical techniques and frequency of sampling. The ambient air quality monitoring was conducted from 15 th January 2016 to 8 th April 2016 representing partly winter and partly pre-monsoon season Methodology Adopted for Air Quality Survey Selection of Sampling Locations The baseline status of the ambient air quality has been assessed through a scientifically designed ambient air quality monitoring network. The design of monitoring network in the air quality surveillance program has been based on the following considerations: Meteorological conditions on synoptic scale; Topography of the study area; Representatives of regional background air quality for obtaining baseline status; and Representatives of likely impact areas. Ambient Air Quality Monitoring (AAQM) stations were set up at ten locations with due consideration to the above mentioned points. Table gives the details of environmental setting around each monitoring station. The locations of the selected stations with reference to the proposed block are given in the same table and depicted in Figure and ambient air sampling photographs are shown as Figure Frequency and Parameters for Sampling Ambient air quality monitoring was carried out at a frequency of two days per week for three months at each location covering from 15 th January 2016 to 8 th April 2016 representing partly winter and partly pre-monsoon season. The baseline data of air environment was monitored for parameters mentioned below: Particulate Matter (PM2.5); Particulate Matter (PM10); Sulphur dioxide (SO2); Oxides of Nitrogen (NOx); Volatile Organic Carbon (VOCs); Total Hyderocarbon; Methane Hydrocarbon;and Non-methane Hydrocarbon VIMTA Labs Limited, Hyderabad C3-29

74 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status The AAQ sampling is carried out as the present revised standards mentioned in the latest Gazette notification of the Central Pollution Control Board (CPCB) (November, 2009). TABLE DETAILS OF AMBIENT AIR QUALITY MONITORING Monitoring Station Name of the Station Well location AAQ1 Bilkhawthir - AAQ2 Kolasib - AAQ3 Bairabi Near HOAC, HOAD AAQ4 Suarhlip Near BRBAA AAQ5 Sethawn - AAQ6 Zamuang - AAQ7 Vawngawn - AAQ8 Mualvum - AAQ9 Mamit - AAQ10 Lengpui Presentation of Primary Data Various statistical parameters like 98 th percentile, average, maximum and minimum values have been computed from the observed raw data for all the AAQ monitoring stations. The results of monitoring carried out are presented in Annexure-V. The summary of these results representing part of winter season are given in Table These are compared with the standards prescribed by Central Pollution Control Board (CPCB). Summary of Observations partly winter and partly pre-monsoon season (2016) o Out of the ten locations the minimum and maximum concentration for PM10 were varied between 37.7 to 46.0 g/m which are well within the NAAQ standard i.e 100 g/m 3. o The minimum and maximum concentration PM2.5 were varied between 11.6 to 15.8 g/m 3 respectively during the study period which are well within the NAAQ standard i.e 60 g/m 3. o The concentrations of SO2 were varied between 7.9 to 15.0 g/m 3 which are well within the NAAQ standard i.e 80 g/m 3. o The concentrations of NOx were varied between 11.0 to 17.3 g/m 3 respectively which are well within the NAAQ standard i.e 80 g/m 3. o The minimum and maximum concentration for CO during the study period was observed as 100 to 239 g/m 3 which are well within the NAAQ standard i.e 2000 g/m 3. o The minimum and maximum concentration for total hydrocarbons, methane hydrocarbons and non-methane hydrocarbons during the study period were observed as 101 to 166 g/m 3, 50 to 95 g/m 3 and 40 to 96 g/m 3 respectively. o The concentration of VOCs is observed in the range of <0.1 ppm. o Ozone values in all the locations are observed to be less than 2.0 µg/m 3. o Nickel values in all the locations are observed to be less than 1.0 ng/m 3. o Ammonia concentration observed in all the locations is less than 20.0 µg/m 3. o PAH concentration in all the locations was found to be < ng/m 3. o BaP values observed in all the locations are <1.0 ng/m 3. o Benzene concentration was observed in all the locations are <1.0 ng/m 3. VIMTA Labs Limited, Hyderabad C3-30

75 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status FIGURE AIR QUALITY SAMPLING LOCATIONS VIMTA Labs Limited, Hyderabad C3-31

76 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Air monitoring at Baiarbi Air monitoring at Mamit FIGURE AIR MONITORING PHOTOGRAPHS VIMTA Labs Limited, Hyderabad C3-32

77 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Monitoring Station TABLE-3.6.2(A) SUMMARY OF AMBIENT AIR QUALITY RESULTS Locations PM10 (µg/m 3 ) PM2.5 (µg/m 3 ) SO2 (µg/m 3 ) NOx (µg/m 3 ) Max Min Avg 98 th %le Max Min Avg 98 th %le Max Min Avg 98 th %le Max Min Avg 98 th %le AAQ1 Bilkhawthir AAQ2 Kolasib AAQ3 Bairabi AAQ4 Suarhlip AAQ5 Sethawn AAQ6 Zamuang AAQ7 Vawngawn AAQ8 Mualvum AAQ9 Mamit AAQ10 Lengpui Range CPCB Standards TABLE (B) SUMMARY OF AMBIENT AIR QUALITY RESULTS Monitoring Locations CO (µg/m 3 ) THC (µg/m 3 ) CH4 HC (µg/m 3 ) Non-CH4 HC (µg/m 3 ) VOC (ppm) Station Max Min Avg 98 th %le Max Min Avg 98 th %le Max Min Avg 98 th %le Max Min Avg 98 th %le Max Min Avg 98 th %le AAQ1 Bilkhawthir <0.1 <0.1 <0.1 <0.1 AAQ2 Kolasib <0.1 <0.1 <0.1 <0.1 AAQ3 Bairabi <0.1 <0.1 <0.1 <0.1 AAQ4 Suarhlip <0.1 <0.1 <0.1 <0.1 AAQ5 Sethawn <0.1 <0.1 <0.1 <0.1 AAQ6 Zamuang <0.1 <0.1 <0.1 <0.1 AAQ7 Vawngawn <0.1 <0.1 <0.1 <0.1 AAQ8 Mualvum <0.1 <0.1 <0.1 <0.1 AAQ9 Mamit <0.1 <0.1 <0.1 <0.1 AAQ10 Lengpui <0.1 <0.1 <0.1 <0.1 Range <0.1 CPCB Standards VIMTA Labs Limited, Hyderabad C3-33

78 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 3.7 Water Quality Selected water quality parameters of ground water and surface water resources within block area for the study has been carried out for assessing the water environment and evaluate anticipated impact of present project. Understanding the water quality is essential in preparation of Environmental Impact Assessment and to identify critical issues with a view to suggest appropriate mitigation measures for implementation. The purpose of this study is to: Assess the water quality characteristics for critical parameters; and Predict the impact of water quality due to the proposed block and related activities. Two surface water sources and seven ground water sources covering entire block area were examined for physico-chemical, heavy metals and bacteriological parameters. The samples were collected and analysed once during the study period. The samples were analyzed as per the procedures specified in 'Standard Methods for the Examination of Water and Wastewater' published by American Public Health Association (APHA) Water Sampling Locations In the study area, 4 surface and 6 ground water samples were collected for winter season (15 th January 2016 to 8 th April 2016). These samples were taken as grab samples and were analyzed for various parameters to compare with the standards. The water sampling locations are listed below in Table and are depicted in Figure and water sampling photographs are shown as Figure The results of monitoring of surface and ground samples carried out for the study are presented in Table and Table TABLE DETAILS OF WATER SAMPLING LOCATIONS Sr. No. Sampling Location Location Well locations Surface Water 1 SW1 Bulvng Lui Near HOAC 2 SW2 Pakwa Nadi - 3 SW3 Borai Lui - 4 SW4 Gutur River - Ground Water 1 GW1 Kolasib - 2 GW2 Bairabi Near HOAD 3 GW3 Suarhlip Near BRBAA 4 GW4 Mualvum - 5 GW5 Mamit - 6 GW6 Lengpui - VIMTA Labs Limited, Hyderabad C3-34

79 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status FIGURE WATER SAMPLING LOCATIONS VIMTA Labs Limited, Hyderabad C3-35

80 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Surface water sampling at Borai Lui Ground water sampling at Lengpui Presentation of Results Surface Water Quality FIGURE WATER SAMPLING PHOTOGRAPHS The results for the surface water samples analysed are presented in Table The analysis results of surface water samples indicate that the ph value was observed to be Electrical conductivity of surface water samples was observed to be The Total Dissolved solids were observed about mg/l. Sulphates were found to be in the range of mg/l, and Nitrates were found to be in the range of mg/l which are with in the prescribed limits only. Fluoride concentration was found to be mg/l the samples. Ground Water Quality The results for the ground water samples analysed are presented in Table The analysis results of ground water samples showed the ph in range of The maximum value was observed at GW6 and the minimum value observed at GW1 whereas the prescribed limit of is 6.5 to 8.5. VIMTA Labs Limited, Hyderabad C3-36

81 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status Colour of the samples ranged from Hazen whereas the prescribed limit is 5 to 15 Hazen. Turbidity of the samples ranged from 2-4 NTU whereas the prescribed limit is 1 to 5 NTU. Electrical conductivity of the samples ranged from µs/cm. The Total Hardness of the samples ranged from mg/l. The maximum value was observed at GW1 and the minimum value observed at GW7 whereas the prescribed limit of 200 mg/l. Calcium concentrations ranged from mg/l r respectively whereas the prescribed limit of mg/l. Magnesium concentrations ranged from mg/l respectively whereas the prescribed limit of mg/l. The Total Dissolved solids of the samples ranged from mg/l. The maximum TDS was observed at GW1, and where as the minimum value observed at GW7. The TDS values are well with in the prescribed limit of 500 mg/l Range of Chlorides concentrations at all the locations mg/l whereas the prescribed limit is mg/l. Range of Sulphates concentrations at all the locations as mg/l whereas the prescribed limit is mg/l. Similarly, Nitrates are also found to be ranging between mg/l whereas the prescribed limit is 45 mg/l. Fluoride concentrations are ranging in between mg/l and are found to be within the permissible limits mg/l. Iron concentrations in ground waters varied from mg/l whereas the prescribed limit is 0.3 mg/l. All other metal concentrations are observed to be below detectable limits. Based on the above results it is evident that all of the parameters in ground water fairly meet the desirable standard limits of IS: VIMTA Labs Limited, Hyderabad C3-37

82 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status TABLE SURFACE WATER QUALITY Sr. No. Parameters UOM SW1 SW2 SW3 SW4 1 ph Color Hazen Conductivity µs/cm Total Dissolved Solids mg/l Dissolved Oxygen mg/l Biological Oxygen Demand mg/l <3 <3 <3 <3 7 Chemical Oxygen Demand mg/l <5 <5 <5 <5 8 Total Hardness mg/l Total Alkalinity mg/l Calcium as Ca mg/l Magnesium as Mg mg/l Chlorides as Cl mg/l Residual Free Chlorine mg/l <0.2 <0.2 <0.2 < Phosphates as PO4 mg/l <0.1 <0.1 <0.1 < Sulphates as SO4 2- mg/l Fluorides as F mg/l Nitrates as NO3 mg/l Sodium as Na mg/l Potassium as K mg/l Total Boron as B mg/l Phenolic Compounds mg/l <0.001 <0.001 <0.001 < Cyanides mg/l <0.02 <0.02 <0.02 < Oil and Grease mg/l <1.0 <1.0 <1.0 < Cadmium as Cd mg/l <0.003 <0.003 <0.003 < Arsenic as As mg/l <0.01 <0.01 <0.01 < Copper as Cu mg/l <0.01 <0.01 <0.01 < Lead as Pb mg/l <0.01 <0.01 <0.01 < Iron as Fe mg/l Chromium as Cr +6 mg/l <0.05 <0.05 <0.05 < Selenium as Se mg/l <0.01 <0.01 <0.01 < Zinc as Zn mg/l Aluminium as Al mg/l <0.01 <0.01 <0.05 < Mercury as Hg mg/l <0.001 <0.001 <0.01 < SAR Insecticides mg/l Absent Absent Absent Absent 36 Anionic Detergents as MBAs mg/l <0.2 <0.2 <0.2 < Total Coliform MPN/1 00ml VIMTA Labs Limited, Hyderabad C3-38

83 wells in Existing NELP Block AA-ONN- 2001/2, Kolasib & Mamit District, Mizoram Chapter-3 Baseline Environmental Status 7 TABLE GROUND WATER QUALITY Sr. No. Parameter Unit Limits as per IS10500 GW1 GW2 GW3 GW4 GW5 GW6 GW7 1 ph (NR) Colour Hazen 5(25) Taste - Agreeable Ag Ag5 Ag Ag Ag Ag Ag 4 Odour - Agreeable Ag Ag Ag Ag Ag Ag Ag 5 Conductivity µs/cm $ Turbidity NTU 1(5) TDS mg/l 500(2000) Total Hardness as CaCO3 mg/l 200(600) Total Alkalinity mg/l 200(600) Calcium as Ca mg/l 75(200) Magnesium as Mg mg/l 30(100) Residual Chlorine mg/l 0.2(1.0) <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 < Boron as B mg/l 0.5(1.0) Chlorides as Cl mg/l 250(1000) Sulphates as SO4 mg/l 200(400) Fluorides as F mg/l 1.0(1.5) Nitrates as NO3 mg/l 45(NR) Sodium as Na mg/l $ Potassium as K mg/l $ Phenolic Compounds mg/l 0.001(0.002) <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 < Cyanides mg/l 0.05(NR) <0.02 <0.02 <0.02 <0.02 <0.02 <0.02 < Anionic Detergents mg/l 0.2(0.1) <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 < Mineral Oil mg/l 0.5(NR) <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Cadmium as Cd mg/l 0.03(NR) <0.003 <0.003 <0.003 <0.003 <0.003 <0.003 < Arsenic as As mg/l 0.01(0.05) <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Copper as Cu mg/l 0.05(1.5) <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Lead as Pb mg/l 0.01(NR) <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Manganese as Mn mg/l 0.1(0.3) <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Iron as Fe mg/l 0.3(NR) Total Chromium as Cr mg/l 0.01(NR) <0.05 <0.05 <0.05 <0.05 <0.05 <0.05 < Selenium as Se mg/l 0.01(NR) <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Zinc as Zn mg/l 5(15) Aluminium as Al mg/l 0.03(0.2) < <0.01 < < Mercury as Hg mg/l 0.001(NR) <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 < Pesticides mg/l Absent Absent Absent Absent Absent Absent Absent Absent 36 E.Coli - Absent Absent Absent Absent Absent Absent Absent Absent 37 Total Coliforms MPN/100ml 10 <2 <2 <2 <2 <2 <2 <2 $: Limits not specified as per IS: 10500, UO: Un-Objectionable, Ag-Agreeable, NR-No Relaxation VIMTA Labs Limited, Hyderabad C3-39

84 Chapter-3 Baseline Environmental Status 3.8 Noise Level Survey The main objective of noise monitoring in the study area is to establish the baseline noise levels, and assess the impact of the total noise generated by the proposed drilling operations Identification of Sampling Locations A preliminary reconnaissance survey has been undertaken to identify the major noise generating sources in the area. Noise at different noise generating sources has been identified based on the activities in the village area, ambient noise due to traffic and the noise at sensitive areas like hospitals and schools. The noise monitoring has been conducted for determination of noise levels at ten locations in the study area for winter season (15 th January 2016 to 8 th April 2016). The noise levels at each location were recorded for 24 hours. The environment setting of each noise monitoring location is given in Table and depicted in Figure and noise sampling photographs are shown as Figure VIMTA Labs Limited, Hyderabad C3-40

85 Chapter-3 Baseline Environmental Status FIGURE NOISE MONITORING LOCATIONS VIMTA Labs Limited, Hyderabad C3-41

86 Chapter-3 Baseline Environmental Status Noise monitoring at Lengpui Noise monitoring at Mamit FIGURE NOISE MONITORING PHOTOGRAPHS TABLE DETAILS OF NOISE MONITORING LOCATIONS Monitoring Station Name of the Station Well locations N1 Bilkhawthir - N2 Kolasib - N3 Bairabi Near HOAC, HOAD N4 Suarhlip Near BRBAA N5 Sethawn - N6 Zamuang - N7 Vawngawn - N8 Mualvum - N9 Mamit - N10 Lengpui Method of Monitoring Sound Pressure Level (SPL) measurements were measured at all locations. The readings were taken for every hour for 24 hours. The day noise levels have been monitored during 6 am to 10 pm and night levels during 10 pm to 6 am at all the locations covered in the block area for the study Presentation of Results The statistical analysis is done for measured noise levels at ten locations during winter season. The parameters are analyzed for Lday, Lnight, and Ldn. These results are tabulated in Table Standard noise limits are given in the Table VIMTA Labs Limited, Hyderabad C3-42

87 Chapter-3 Baseline Environmental Status TABLE NOISE LEVELS IN THE STUDY AREA Monitoring Location L10 L50 L90 Leq Lday Lnight Ldn Station N1 Bilkhawthir N2 Kolasib N3 Bairabi N4 Suarhlip N5 Sethawn N6 Zamuang N7 Vawngawn N8 Mualvum N9 Mamit N10 Lengpui CPCB standards TABLE AMBIENT NOISE STANDARDS Area Code Category of Area Noise Levels (db (A) Leq (Limits) Day time Night time A Industrial Area B Commercial Area C Residential Area D Silence Zone Ambient Noise Standards of CPCB Observation of Results The daytime (Lday) noise levels at all the locations are observed to be in the range of 35.6 db (A) to 48.0 db (A) which are well within the prescribed daytime noise standard for residential zone i.e 55 db(a). The night time (Lnight) noise levels at all the locations were observed to be in the range of 31.2 db (A) to 44.2 db (A) which are well within the prescribed night time noise standard for residential zone i.e 45 db(a). It is observed that the noise levels at residential locations are within the prescribed limit of CPCB ambient noise standard. 3.9 Ecological Studies Introduction The primary ecology survey was conducted during study period along with forest officals. Ecological studies are one of the important aspects of Environmental Impact Assessment with a view to conserve environmental quality and biodiversity. Ecological systems show complex inter-relationships between biotic and abiotic components including dependence, competition and mutualism. Biotic components comprise of both plant and animal communities, which interact not only within and between themselves but also with the abiotic components a viz. physical and chemical components of the environment. VIMTA Labs Limited, Hyderabad C3-43

88 Chapter-3 Baseline Environmental Status Generally, biological communities are good indicators of climatic and edaphic factors. Studies on biological aspects of ecosystems are important in Environmental Impact Assessment for safety of natural flora and fauna. The biological environment includes terrestrial and aquatic ecosystems. The animal and plant communities co-exist in a well-organized manner. Their natural settings can get disturbed by any externally induced anthropological activities or by naturally occurring calamities or disaster. So, once this setting is disturbed, it sometimes is either practically impossible or may take a longer time to come back to its original state. Hence, changes in the status of flora and fauna are an elementary requirement of Environmental Impact Assessment studies, in view of the need for conservation of environmental quality and biodiversity. Information on flora and fauna was collected within the study area. Relevant details on aquatic life within the study area were collected from related government offices. The present report gives the review of published secondary data and the results of field sampling conducted during January March, Objectives of Ecological Studies The present study was undertaken with the following objectives: To assess the nature and distribution of vegetation in and around the block area; To assess the distribution of animal life spectra; To understand the productivity of the water bodies; and To ascertain migratory routes of fauna and possibility of breeding grounds Methodology adopted for the Survey To achieve the above objectives, a detailed study of the entire Block area was undertaken. The different methods adopted were as follows: o o o o Compilation of secondary data with respect to the study area from published literature and Government agencies; Generation of primary data by undertaking systematic ecological studies in the area; Discussion with local people so as to elicit information about local plants, animals and their uses; and Gathering data for ethno-biology. The list of proposed ONGC wells drilling locations and list of terrestrial ecological locations as given in Table and Table Forest block with in Mamit district in Mizoram Dampa Wildlife Sanctuary comprising of Dampa Tiger Reserve which is situated about 75.3 km / SSW direction from HOAD well location, in NELP Block. The presence of endangered species such as Tigers and others endangered cats, VIMTA Labs Limited, Hyderabad C3-44

89 Chapter-3 Baseline Environmental Status comprising of larger track of the sanctuary area near the oil drilling blocks in Mizoram state Table TABLE FOREST BLOCKS WITHIN STUDY AREA Sr. No Forest Blocks 1 Dampa Tiger Reserve about 75.3 Km/ SSW, comprising of huge area of Mamit district, in the block area 2 Kolasib Forest Block 3 Mamit Forest Block 4 Innerline Forest Reserve Terrestrial Ecological Status: Primary Survey A preliminary survey was made in the study block area. The primary data was generated through: 1. Preparing a general checklist of all plants encountered in the study area. This would indicate the biodiversity for wild and cultivated plants. 2. Determining the bird population of migratory and local birds by taking 10 random readings at every location; 3. Observing mammals, amphibians and reptiles, noting their calls, droppings, burrows, pugmarks and other signs; and 4. Local inhabitants were interviewed for use of plants and animals and to get ethno biological data. List of Terrestrial Ecological Locations as given in Table TABLE DETAILS OF PROPOSED DRILLING LOCATIONS Sr. Proposed Location Tentative Well Coordinates (WGS-84) No Latitude Longitude 1 HOAC HOAD TABLE DETAILS OF TERRESTRIAL ECOLOGICAL SAMPLING LOCATIONS Station Code TE-1 TE-2 TE-3 TE-4 TE-5 Name of the Station Vegetation near Kolasib Vegetation near North Thingdaw Vegetation near Zawlnuam Vegetation near Mamit Vegetation near Tlangnuam VIMTA Labs Limited, Hyderabad C3-45

90 Chapter-3 Baseline Environmental Status FIGURE ECOLOGICAL SAMPLING LOCATIONS VIMTA Labs Limited, Hyderabad C3-46

91 Chapter-3 Baseline Environmental Status Threatened Plant Species and Agriculture National threatened species are those found only in small numbers or those very near to extinction in the country. India has a list of threatened species at the All India level, published by the Botanical Survey of India entitled Red Data Book. No species observed in the study region comes under the category of threatened species out of 134 plant species. However, there is intense anthropogenic pressure on flora, fauna and forest resources, which are observed to be dwindling. Agriculture The staple food of the people in the study region is rice and wheat. Agro-climatic conditions of the area provide a range of potentialities for growing cash crop like off seasonal vegetable i.e. onion, chilly, brinjal, bhindi, fruits and flowers, kitchen gardening is also common because of sufficient available space around house. Main agricultural crop production in study area is paddy (Oryza sativa), supplemented by wheat (Triticum aestivum). The common rabbi crops grown in the study area are wheat, gram, mustard, taramira, potato, carrot, pea etc. whereas rice, jowar, arhar, tur, moong, til, groundnut, soyabean, chilly, ginger, etc are kharif crops. Other than cereals fruits like mango, pineapple, orange, jackfruit, banana, litchi, lemon, papaya, sapota, and guava are also grown in large quantity. The list of the agricultural crops in the study area is given in Table TABLE LIST OF AGRICULTURAL CROPS Sr. No. Scientific Name Common Name Rabi Cereals 1 Oryza sativa Rice 2 Zea mays Maize Pulses 1 Phaseolus Gram Oil Seeds Brassica juncea Mustard Vegetables 1 Coriandrum anum Coriander 2 Allium sativum Garlic 3 Capsicum anum Chilly 4 Solanum tuberosum Potato 5 Daucus carata Carrot 6 Pisum sativum Pea Kharif Cereal 1 Oryza sativa Rice 2 Sorghum vulgarum Jowar 3 Cajanus cajan Arhar 4 Phaseolus angularis Urd 5 Phaseolus mungo Moong Oil Seed 1 Seasamum Til VIMTA Labs Limited, Hyderabad C3-47

92 Chapter-3 Baseline Environmental Status Sr. No. Scientific Name Common Name 2 Arachys hypogea Groundnut 3 Glycine max Soya bean Vegetables 1 Capsicum anum Chilly 2 Zingiber officinale Ginger Others 1 Potato 2 Saccarum officianalis Sugarcane Source: Directorate of Agriculture, Aizwal, Mizoram Floristic Composition of FORESTS and FAUNA with Indian Wildlife Schedules The Forests in Mamit block are generally covered with hills and practically very rare on moderate slopes due to cultivation. Composition and condition of crops are affected by nature and depth of soil, the topography and biotic factors, of which jhuming is the most significant, Forest crop of the tract dealt with is heterogeneous and most of the tract have lost its original crop character. Trees of 200 to 270 cms girth are still common and upto 300 cms and over is girth are occasionally met with in the inaccessible area. The top canopy is represented by tree species like Michelia champaca, Terminalia myriocarpa, Dipterocarpus species, Artocarpus chaplasa, Magnifera indica (wild variety), Acrocarpus fraxinifolius, Castonopsis species, Cedrella toona, Albizia procera, Sapium species, Morus species, Schima species etc. The middle canopy is represented by Ficus species, Bauhinia species, Spondia species, Oroxylum indicum, Syzygium cuminii, Cinnamomum glanduliferum, Lagerstroemia speciosa, Erythrina species etc. Mesua ferrea, Amoora wallichii etc. represent the lower canopy. Woody climbers (lianas) and small size shrubs also add to the varied composition of middle canopy. In general the crop composition of natural forest of the area shows irregularity in various parameter. The area out of the tract dealt which has miscellaneous forests, jhum land and bamboo forests. However, in patches where good forest exists are available in a scattered manner. The Forests in Kolasib are composed of miscellaneous species without a single or two species dominating the forests. Forest covers are usually absent or negligible where the slope is moderate and convenient for cultivation. Forest covers are also absent in some low lying areas where wet rice cultivation is being done. The composition of crop, quantity, health and size are influenced by the depth of the soil, topography, biotic factors (especially jhumming). Excepting those areas which are difficult to access, trees of exploitable size are rare due to over exploitation of the area. The over woods consist mainly of Michelia champaca, Terminalia myriocarpa,artocarpus chaplasa, Cedrella toona etc. underwoods usually comprise of mesua ferrea, syzygium cuminii, Bauhinia spp. Amoona wallichii, Derris robusta etc. Undergrowth consists mainly of Clerodendron, solanum spp, Ageretum conizoyides, Bidens biternata, Begonia dioica, Vermonia cineria etc. VIMTA Labs Limited, Hyderabad C3-48

93 Chapter-3 Baseline Environmental Status List of Wildlife Sling Mizo Name Common Name Scientific Name Schedule of Indian Wildlife (Protection) Act, Bak-sai Indian Flying Fox Pteropus giganteus Sch-V 2 Biang Particoloured Flying Hylopetes alboniger Sch-I Squirrel 3 Bui-ke-lek Short-tailed Mole Talpa micrura Sch-V 4 Bui-sen Bay Bamboo rat Cannomys Sch-V 5 Bui-pui Red-cheeked Bamboo Rhizomys Sch-V Rat erythrogenys 6 Bui-luang-par Hoary Bamboo Rat Rhizomys pruinosus Sch-V 7 Chai-chim Indian Field Mouse Mus booduga Sch-V 8 Che-pa Northern Tree-shrew Tupaia belangeri Sch-V 9 Chhim-tir Grey Musk Shrew Suncus murinus Sch-V 10 Chinghnia Wild Dog Cuon alpinus Sch-II 12 Dawr Phayres Leaf Monkey Presbytis phayrei Sch-I 13 Hlei-kap-sen Red-bellied Palla s Callosciurus Sch-II Squirrel erythreaus 14 Hlei-zawng Himalayan Hoary-bellied C.pygerythrus Sch-II Squirrel 15 Keisen Goden Cat Fells temmincki Sch-II 18 Mang-tir/Sa-mang Malayan Sun Bear Ursus malayanus 19 Ngau Capped Langur Presbytis pileatus Sch-I 20 Ngau Silvered Leaf Monkey Presbytis cristatus Sch-II 21 Ngau-sen/Ngau-ireng Golden Langur Presbytis geei Sch-II 22 Nghar-thing-awn Spotted Linsang/Tiger Prionodon Sch-I Civet pardicolor 23 Ngharbuang Fishing Cat Felis veverrina Sch-I 24 Phivawk Hog Badger Arctonyx collaris Sch-I 25 Ramsial/Sele Indian Bison Bosgaurus Sch-I 26 Safia Yellow throated Marlen Martes flavigula Sch-II 27 Sahmaitha Chinese ferret badger Melogale moschata Sch-I 28 Sa-huai Slow Loris Nycticebus coucang Sch-I 29 Sahram Clawless Otter Aonix cinerea Sch-I 30 Sai Indian Elephant Elephan maximus Sch-I 31 Sakhi Barking Deer Muntiacus muntijak Sch-III 32 Sakuh Indian Porcupine Hystrix indica Sch-III 33 Sanghar Leopard Cat Felis Bengalensis Sch-II 34 Saphu Indian Pangolin Manis crassicaudata Sch-I 35 Sa-phai-ruang Crab-eating Mongoose Herpestes aura Sch-II 36 Sathar Goral Nemorheadus goral Sch-I 37 Sauak Jungle Cat Felis chaus Sch-I 38 Savawm Black Bear U.thibetanus Sch-II 39 Sa-zaw-Zaw-buang) Himalayan Palm Civet Paguma larvata Sch-II 40 Sa-zaw(Zaw-hang) Toddy Cat/Common Palm Paradoxurus Sch-II Civet hermahroditus 41 Sazu Common Mouse Rat Rattus rattus Sch-II 42 Sazuk Sambar Cervus unicolor Sch-III 43 Sihal Bengal Fox Vulpes bengalensis Sch-II 44 Tlum-therte Small Indian Civet Viverricular indica Sch-II 45 Vahluk Common Flying Squirrel Petaurista Sch-I petaurista 46 Zamphu Binturong/Bear-cat Arctictis binturong Sch-I 47 Zawng Rhesus Macaque Macaca mulatta Sch-II 48 Zawng-mawt Stump-tailed Macaque Macaca arctoides Sch-II 49 Zawng-hmeltha Pig-tailed Macaque Macaca leonine Sch-II 50 Zohang Small Indian Mongoose Herpestes favanicus Sch-II VIMTA Labs Limited, Hyderabad C3-49

94 Chapter-3 Baseline Environmental Status Sling Mizo Name Common Name Scientific Name Schedule of Indian Wildlife (Protection) Act, Zutam Bandicoot Rat Bandicota indica Sch-V 52 Zuthel White-tailed Wood Rat Rattus blanfordi Sch-II 53 Toddy Cat/Common Palm Paradoxurus Sch-II Sa-zaw(Zaw-hang) Civet hermahroditus 54 Sazuk Sambar Cervus unicolor Sch-III 55 Sihal Jackal Vulpes bengalensis Sch-II 56 Tlum-pui Large Indian Palm Civet Viverra zibetha Sch-II 57 Zawng-hmeltha Pig-tailed Macaque Macaca nemestrina Sch-II 58 Zuthel White-tailed Wood Rat Rattus blanfordi Sch-II 59 Keipui Tiger Panthera tigris Sch-I 61 Keisen Golden Cat Fells temmincki Sch-II 62 Keite Leopard Panthera pardus Sch-I 63 Kelral Clouded Leopard Neofelis nebulosa Sch-I 69 Mang-tir/Sa-mang Malayan Sun Bear Ursus malayanus Sch-I 70 Trachypithecus Sch-I Ngau Capped Langur pileatus 72 Spotted Linsang/Tiger Civet Prionodon perdicolor Nghar-thing-awn Aves ( BIRDS) 1 Bawng Scarlet Minivet Pericrocotus flammeus Sch-II Sch-IV 2 Bawng irpaw Grey-chinned Minivet P.Solaris Sch-IV 3 Bawngmeisei Long tailed Minivet P.mariae ethologus Sch-IV 4 Bawngte Short tailed Minivet P.brevirostris Sch-IV 5 Bemkawng Grey Tree pie Dendrocitta Sch-IV formosae 6 Buarchawm Blue-napped Pitta Pitta nipalensis Sch-IV 7 Buarchawm lu-uk Hooded Pitta Pitta sordida Sch-IV 8 Bullut Mountain Imperial pigeon Ducula badia Sch-IV 9 Bullutte Green Imperial Pigeon Ducula aenea Sch-IV 10 Changkak Black Drongo Dicrurus adsimilis Sch-IV 11 Changkakte Bronzed Drongo Dicrurus aeneus Sch-IV 12 Changsen Maroon Oriole Oriolus traillii Sch-IV 13 Chang-hlawi Lesser Racket-tailed Dicrurus remifer Sch-IV Drongo 14 Changrual Blue-winged Siva Minla Sch-IV cyanouroptera 15 Chawngzawng House Sparrow Passer domesticus Sch-IV 16 Cheih Chin Hills Green shrikebabbler Pteruthius xanthochlorus hybridus Sch-IV 17 Chhawlhring-lu-eng Orange-bellied Leaf-bird Chloropsis Sch-IV hardwickii 18 Chhawlhring-thlapaw Blue-winged Leaf bird Chloropsis Sch-IV cochinchinensis 19 Chhawlhringlu-eng Gold- fronted Leaf bird Chloropsis aurifrons Sch-IV 20 Chhemhur-uk Brown Shrike Lanius cristatus Sch-IV 21 Chhemhur Black-headed Shrike Lanius shack Sch-IV tricolor 22 Chhemhur Grey-backed Shrike Lanius tephronotus Sch-IV 23 Chhenhurpaw Long-tailed Shrike L.schach tricolor Sch-IV 24 Chhimbuk Spot-bellied Eangle Owl Bubo nipalensis Sch-IV 25 Chhimbuk Burmese Collared Scops Otus bakkamoena Sch-IV Owl lettia 26 Chhimbuk Common Scops- Owl Otus Scops Sch-IV 27 Chhimbuk Spotted Scops-Owl Otus spilocephalus Sch-IV 28 Chhimbuk( Va-uk) Brown Hawk Owl Ninox scutulata Sch-IV 29 Chhimbukte Barred Jungle Owlet Glaucidium Sch-IV VIMTA Labs Limited, Hyderabad C3-50

95 Chapter-3 Baseline Environmental Status Sling Mizo Name Common Name Scientific Name Schedule of Indian Wildlife (Protection) Act, 1972 radiatum 30 Chhuangtuar/Va-seek Hoopoe Upupa epops Sch-IV 31 Chi-ling Yellow-throated Fulvetta Alcippe cinerea Sch-IV 32 Chinrang Black backed forktail Enicurus Sch-IV inemaculatus 33 Chirh-dawt Fantail Snipe Gallinago gallinago Sch-IV 34 Chirh-dawt Pintail Snipe Gallinago stenura Sch-IV 35 Chirh-dawt-lian-chi Woodcock Scolopax Sch-IV 36 Chikkut Mountain Bulbul Hypsipetes Sch-IV viridescens 37 Chingpirinu Brown-wood-Owl Strix Sch-IV leptogrammica 38 Chingpirinu Himalaya Wood Owl Strix aluco nivicola Sch-IV 39 Chip Olive-backed Tree Pipit Anthus Sch-IV novaeseelandiae 40 Choak Jungle Crow Corvus Sch-IV macrorhynchos 41 Daikat Golden headed tailor bird Orthotamus Sch-IV Cucullatus 42 Dawithiama arpa Mrs. Gould s Sunbird Aethopyga gouldiae Sch-IV 43 Dawithiama arpa Crimson Sunbird Aethopyga siparaja Sch-IV Dulsen 44 Dawithiama arpa Fire-tailed Sunbird Aethopyga Sch-IV Meisen ignicauda 45 Dawkek White-throated Bulbul Cringer flaveolus Sch-IV 46 Dawntliang Green Magpie Cissa chinensis Sch-IV 49 Dil Arte Little Grebe Podiceps ruficollis Sch-IV 50 Dumar Purple Swamp-hen Porphyrio porphyrio Sch-IV 51 Fanghmir thloh Pale-headed Woodpecker Gecinulus grantia Sch-IV 52 Fanghmir thloh Rufous Woodpecker Micropternus Sch-IV brachyurus 53 Fuanhawr Asian House-martin Delichon dasypus Sch-IV 54 Fuanhawr Nepal House-martin Delichon nipalensis Sch-IV 55 Hmarvaiva Pied Myna Sturnus contra Sch-IV 56 Hmunchhe arpui Pygmy Wren-babbler Pnoepyga pusilla Sch-IV 57 Hrangkir Asian Barred Owlet Glauacidium Sch-IV cuculoides 58 Hrangkir/ Collared Pigmy Owlet Glaucidiulbrodiei Sch-IV 59 Huipui Thick-billed Green Pigeon Treron curvirostra Sch-IV 60 Irliak Large Cuckoo Shrike Coracina Sch-IV novaehollandiae 61 Irliakte Dark-winged Cuckoo C.melachistos Sch-IV Shrike 62 Kawr vaiva Collared Myna Acridotheres Sch-IV albocinctus 63 Kaikuangral Blyth s Kingfisher Alcedo Hercules Sch-IV 64 Kaikuangral Stork-billed Kingfisher Pelargopsis Sch-IV capensis capensis 65 Kaikuangral Crested Kingfisher Ceryle lugubris Sch-IV 66 Kaikuangral Pied Kingfisher Ceryle rudis Sch-IV 68 Kaikuangral te chi Black-backed Kingfisher Ceyx erithacus Sch-IV 69 Kaikuangral Awrvar White-throated Halcyon smyrnensis Sch-IV Kingfisher 70 Kaikuangral-ludum Back-capped Kingfisher Halcyon pileata Sch-IV 71 Kaikuangralte Common Kingfisher Alcedo atthis Sch-IV 72 Kaikuangraluk Ruddy Kingfisher Halcyon coromanda Sch-IV 73 Kanghlai Lesser Adjutant Leptoptilos Sch-IV VIMTA Labs Limited, Hyderabad C3-51

96 Chapter-3 Baseline Environmental Status Sling Mizo Name Common Name Scientific Name Schedule of Indian Wildlife (Protection) Act, 1972 Javanicus 74 Kawlhawk Wreathed Hornbill Rhyticeros Sch-IV undulates 75 Kawl-rit/Pi-kawl-rit Brown-eared Bulbul Hypsip[etes Sch-IV flavalus 76 Kawl va sir Red winged shrikebabbler Pteruthius Sch-IV flaviscapis 77 Khawimu-chinrang White Wagtail Motacilla alba Sch-IV 78 Kham- va-mur Dark-backed Swift Apus acuticauda Sch-IV 79 Kitheihrawk Common Hawk cuckoo Cuculus varius Sch-IV 80 Kitheihrawk Large Hawk-cuckoo Cuculus Sch-IV sparverioides 81 Kireuh Streaked Spider Hunter Archnothera magna Sch-IV 82 Klawt Slatey-headed Parakeet Pstillacula Sch-IV himalayana 83 Ko-ro/Koro-lu-par White-rested Laughing Garrulax Sch-IV thrust leucolophus 84 Kulherh nu Crow-billed Drongo Dicrurus annectans Sch-IV 85 Kul herh Hair-crested Drongo Dicrurusll Sch-IV hottentottus 86 Lailen Grey Wagtail Motacilla cinerea Sch-IV 87 Lalruanga Sehnawt Crow Pheasant Centropus sinensis Sch-IV 88 Lawizit Ruby-cheeked Sunbird Anthreptes Sch-IV singalensis 89 Lengder Ashy Wood Swallow Artamus fuscus Sch-IV 90 Liandorit Black Bulbul Hypsipetes Sch-IV madagasdariensis 91 Limchho Brawn-throated Tree Certhia discolor Sch-IV Creeper 92 Lungdup Black Eagle Ictinaetus Sch-IV malayensis 93 Luang tu-bek/mau Rufous Piculet Sasia ochracea Sch-IV Thloh reichenowi 94 Mangkhai-a-ral-veng Red-wattled Lapwing Vanellus indicus Sch-IV 95 Mangkhai-a-ral-veng Grey-headed Lapwing Vanellus cinereus Sch-IV 96 Mangkhai-a-ral-veng Spur-winged or River Vanellus duvaucelli Sch-IV Lapwing 97 Mangkhai-a-ral-veng White-tailed Lapwing Vanellus leucurus Sch-IV 98 Mawntaipirtliak Plaintive Cuckoo Cacomantis Sch-IV merulinus 99 Mawntaipirtliak Lesser Cuckoo Cuculus Sch-IV Poliocephalus 100 Mimsirkut Bar-tailed Cuckoo-Dove Macropygia unchall Sch-IV 101 Mitval Nepal Fulvetta Alcippe nipalensis Sch-IV 102 Muarla Crested Honey Buzzard Pernis Ptilorhyncus Sch-IV 103 Muawmsen Oriental Hobby Falco severus Sch-IV 104 Mungek Peregrine Falcon Falco perefrinus Sch-IV 105 Muarla Rufous-bellied Hieraaetus badius Sch-IV 106 Mu-te Shikra Accipiter badius Sch-I 107 Mu-ni-ngal-dang Crested Goshawk Accipitertrivirgatus Sch-I 108 Mu-te Besra Accipiter virgatus Sch-I 109 Mu-kel-rang Black Baza Aviceda leuphotes Sch-I 110 Mu Common Buzzard Buteo buteo Sch-I 111 Mu-te Eurasian Kestrel Falco tinnunculus Sch-I 112 Muvanlai Crested Serpent Eagle Spilornis cheela Sch-I 113 Ngal Vapual Spot-breasted Scimitar- Pomatorhinus Sch-IV Babbler Erythrocnemis Sch-IV 114 Ngal Vapual Coral-billed Scimitar- Pomatorhinus Sch-IV VIMTA Labs Limited, Hyderabad C3-52

97 Chapter-3 Baseline Environmental Status Sling Mizo Name Common Name Scientific Name Schedule of Indian Wildlife (Protection) Act, 1972 babbler Ferruginosus phayrei 115 Ngal Vapual Large Scimitar-babbler Pomatorhinus Sch-IV hypoleucos 116 Ngal Vapual Rufous-necked Scimitar Pomatorhinus Sch-IV ruficollis bakeri 117 Ngal Vapual Slaty-headed Scimitarbabbler Pomatorhinus Sch-IV schisticeps 118 Ngawihup/Kawlpui White-bellied Heron Ardea insignis Sch-IV saruhhak 119 Ngaw Lailen Forest Wagtail Motacilla indica Sch-IV 120 Pengleng House Swift Apus affinis Sch-IV 121 Va te chikhat Yellow-breasted Babbler Macronous gularis Sch-IV 122 Vathu Oriental Turtle Dove Streptopelia Sch-IV orientalis 123 Vavu Mrs. Hume s Pheasant Syrmaticus humiae Sch-I 124 Va-zar(Zar-fek) Yellow-throated Garrulax galbanus Sch-IV galbanus 125 Va-zar(Zar-fek) Necklaced Laughing Garrulax Sch-IV thrush moniligerus 126 Va-zar(Zarpui-thiawrh) Black-gorgeted Laughing Garrulax pectoralis Sch-IV thrush 127 Vazum Green-billed Malkoha Phaeni Sch-IV cophaeustritis 128 Zairumva Common Lora Aegithina tiphia Sch-IV 129 Zetzet Little Spider Hunter Arachonothera Sch-IV 130 Zotuklo Golden-throated Barbet Megalaima frankinii Sch-IV 131 Zo-bul-lut/Bul-lut-tial Speckled Wood Pigeon Columba hodgsonii Sch-IV Reptiles Sl.No Mizo Name Common Name Scientific Name Schedule of Indian Wildlife (Protection) Act, Chawngkawr Mono-cellate Cobra Naja kaouthia Sch-II 2 Daidep Garnot s Gecko Hemidactylus Sch-IV gamoti 3 Laiking Common Calotes Calotes versicolor Sch-IV 4 Laitel Spiny-headed Forest Calotes emma Sch-IV Calotes 5 Rulngan King Cobra Ophiophagus S ch-ii Hannah 6 Rultuha White-lipped pit viper Trimeresurus Sch-II alborabris 7 Rulsakhi Cat snake Boiga ochrecea Sch-II 8 Saphai Eastern Indian/Burmese Python molurus Sch-I Python 9 Satel Yellow Tortoise Indotestudo Sch-II elongate 10 Tangkawng Saw Fish Xenantodon Sch-II cancella 11 U-leuh Spotted Gliding Lizard Draco maculates Sch-II Fishes 1 Nghatun (Tunzem) Rohu Laebo rohita - 2 Nghatun (Tunhang) Rohu Laebo calbasu - 3 Zawngdulinu Gangetic Dolphin Platanista gangetica Sch-I 4 Thaichhawninu Cat Fish Bagarius yurrellii - 5 Nghafunglawr Saw Fish Xenantodon cancella - VIMTA Labs Limited, Hyderabad C3-53

98 Chapter-3 Baseline Environmental Status Sling Mizo Name Common Name Scientific Name Schedule of Indian Wildlife (Protection) Act, Tilapia Tilapia mosambica - 7 Nghadawl Amblifiring godon - mola 8 Nghatun Puntius Puntius ticto - 9 Nghameidum Puntius Puntius sarara - 11 Nghavawk Sport Fish Chana striatus - 12 Ngharul Eel Muraena thyroidea - 13 Nghathinghar Flat Fish Chanda nanaraya - 14 Sport Fish Copper Mahaseer(Sport Acrossochilous - Fish) hexagonalopis 15 Catla Bau (Catla) Catla catla - 16 Mrigal Mrigal Cirrhinus mrigala - 17 Silver carp Silver carp Hypothalmichthys - molitric 18 Grass carp Grass carp Ctenophayngodon - idella 19 Common carp Common carp (Scale Ciprinus corpio - carp) 20 Nghahrah Tor (Sport Fish) Tor pituitora - 21 Nghalim Sport Fish Channa orientalis - Amphibians 1 Utawk Common Asian Toad Bufo mela Sch-IV Aquatic Ecological Status: Primary Survey Introduction The impact of pollution on aquatic ecosystem manifests itself first on the biotic aquatic communities. The species composition of aquatic organisms in natural communities is directly influenced by ambient water quality. The responses of plants to pollutants, when measured quantitatively give an insight about the conditions of existing aquatic ecosystem Plankton Study Protecting the environment and making efficient use of natural resources are two of the most pressing demands in the present stage of social development. The task of preserving the purity of the atmosphere and water basins is of both national and global significance since there are no boundaries to the propagation of anthropogenic contaminants in the water. An essential pre requisite for the successful solution to these problems is to evaluate ecological impacts from the baseline information and undertake effective management plan. So the objective of aquatic ecological study may be outlined as follows: To characterize water bodies like fresh waters; To understand their present biological status; To characterize water bodies with the help of biota; To understand the impact of industrial and urbanization activities; and To suggest recommendations to counter adverse impacts, if any on the ecosystem. VIMTA Labs Limited, Hyderabad C3-54

99 Chapter-3 Baseline Environmental Status To meet these objectives following methods were followed: Generating data by actual field sampling and analysis in these areas through field visits during study period; and Discussion with local people to get the information for aquatic plants and aquatic animals. To fulfill these objectives and to understand the present status of aquatic ecosystem, samples were collected from different fresh water system (river) under investigation. In order to get a clear picture and to assess the various parameters of water, threesampling locations were identified for sampling. Samples were collected during study period. The sampling locations are presented in Table and shown in Figure TABLE DETAILS OF AQUATIC SAMPLING LOCATIONS Sr. No. Code Locations Remarks 1 AE-1 Bulang tat river near Bairabi Fresh water 2 AE-2 Vaak Lui, river near Mamit Fresh water 3 AE-3 Sakhi Lui, river Belkhai Tlang Fresh water Methodology Adopted for Aquatic Studies The biological species specific for a particular environmental conditions are the best indicators of environmental quality. This includes different biological species such as phytoplankton, zooplankton and bacteria. Diatoms, desmids and dinophyceaen members are indicative of clean water conditions. Increasing dominance of diatoms, ciliates, flagellates, chlorophycean and cyanophycean species indicates progressively increasing trophic conditions. Presence of Euglenophyceae indicates high eutrophic conditions. Planktonic rotifers are usually more abundant in fresh water than estuarine waters. It is believed that when crustacean and insect out number other groups the situation reflects the enriched organic conditions of water. Thus, of certain organisms help in classifying water body in trophic levels on knowing its physico chemical characteristics. The plankton samples were collected by using plankton net. The filamentous algae and debris were avoided by filtering through the plankton net. The collected sample was condensed to 100 ml by filtration and the samples were preserved using pinch of Rose Bengal and 10 ml of 4% formaldehyde solution. For the measurement of frequencies of various forms of Phytoplankton and Zooplankton, one drop of the sedimented plankton was mounted on a micro-slide, as many as 20 different microscopic fields situated at more or less even distances from each other were examined, and numbers of individual organisms are counted Phytoplankton Phytoplankton group reported from three locations, 8 species of phytoplanktons were reported. VIMTA Labs Limited, Hyderabad C3-55

100 Chapter-3 Baseline Environmental Status Zooplankton About 6 zooplankton species are recorded from all the three the sampling locations. The list of plankton recorded in fresh water bodies in study area during study period are presented in Table and Table TABLE LIST OF PHYTOPLANKTON SPECIES IDENTIFIED FROM STUDY AREA Sr. No Family Species 1. Bacillariophyceae Navicula sp Diatoma sp Synedra sp 2. Cyanophyceae Chlorella sp Scenedesmus sp Ankistodesmus sp 3. Chlorophyceae Merismopidia sp 4. Euglenophyceae Euglena sp TABLE LIST OF ZOOPLANKTON SPECIES IDENTIFIED FROM STUDY AREA Family Rotifera Arthropoda Zooplankton Species Brachinous sp. Nauplius sp. Acroperus sp. Macrothrix sp. Ceriodaphnia sp. Simocephalus sp Conclusion As per primary survey and secondary data referred, it was concluded that the study areas flora and fauna is ecologically rich and it is also fragmented owing to anthropogenic pressures. The endangered fauna are only present in the core of the forest areas, and there is impact of fragmentation owing to the road construction and extraction of the forest material on non timber forest produce like bamboo in the forests. Instance of Hunting and Poaching are also reported in the forest fringe villages. Thus many of the rare and threatned species were found in the villages Demography and Socio-Economics The demographic and socio- economic conditions prevailing in the block of the proposed drilling of exploratory wells area Meidum, Taitow, Zanlawn Villages in kolasib district, Sauhliap village in Mamit district, Tlangnuam rural development block in Aizawl district of Mizoram is analyzed. The socio-economic data forms the basis for developing a suitable enterprise social responsibility plan to address the needs of the population. VIMTA Labs Limited, Hyderabad C3-56

101 Chapter-3 Baseline Environmental Status The project proponent is committed to take up the socio-economic development initiatives not only to minimize the negative impact on the population and also improve the socio-economic status of population living in block of the wells as its sustained effort as part of corporate social responsibility Methodology Adopted for the Study The methodology adopted for the study mainly includes primary survey and review of published secondary data (District Census Statistical Handbooks and Primary Census Abstract of Census-2011) with respect to population, household size, sex ratio, social stratification, literacy rate and occupational structure for block area Review of Demographic and Socio-Economic Profile-2011 The village wise demographic data of 72 villages and 04 notified towns are falling within the block of the project site as per the 2011 census is given in Annexure- VI. The salient features of the demographic and socio-economic conditions are analyzed and described in the following sections Demography Distribution of Population As per 2011 census the study area consisted of 3,99,283 persons inhabited in study area. The distribution of population in the study area is shown in Table TABLE DISTRIBUTION OF POPULATION Particulars NELP Block Area No. of Households Male Population Female Population Total Population Male Population (0-6 years) Female Population (0-6 years) Total Population (0-6 years) % of 0-6 years population Average Household Size 4.83 % of males to the total population % of females to the total population Sex Ratio (no of females per 1000 males) 1006 Source: District Census Hand Book 2011 Average Household Size The study area has a household size of 4.83 as per 2011 census. Sex Ratio The configuration of male and female indicates that the males constitute to about 49.86% and females to 50.14% of the total population as per 2011 census records. The study area on an average has 1006 females per 1000 males as per VIMTA Labs Limited, Hyderabad C3-57

102 Chapter-3 Baseline Environmental Status 2011 census reports. In comparison to the state sex ratio (Mizoram 976) the study area has recorded more sex ratio. The sex ratio in the study area indirectly reveals certain sociological and cultural aspects in relation with female births Social Structure In the study area, as per 2011 census, 0.17% of the population belongs to Scheduled Castes(SC) and 91.54% to Scheduled Tribes(ST). Overall the data of social stratification reveals that the SC and ST % to population is more than 91.7%, The SC and ST community are marginalized and they are at considered at low level of social strata and calls for a special attention in Social Impact Management Plan for improving their socio-economic status apart from preservation and protection of their art, culture and traditional rights of livelihood. The distribution of population by social structure is shown in Table TABLE DISTRIBUTION OF POPULATION BY SOCIAL STRUCTURE Particulars NELP Block area Schedule caste 660 % To the total population 0.17 Schedule Tribes % To the total population Total SC and ST population % To total population Total population Source: District Census Hand Book Literacy Levels The data of study area reveals that literacy rate of 95.85% as per 2011 census, which is found to be more than state rate of literacy (Mizoram 89.3%). The distribution of literate and literacy rate in the study area is given in Table TABLE DISTRIBUTION OF LITERATE AND LITERACY RATES Particulars NELP Block area Male Population Female Population Total Population Male Population (0-6 years) Female Population (0-6 years) Total Population (0-6 years) Total Population above 7 years Male literates (7+ years) Female literates (7+ Years) Total literates (7+ Years) Male literacy rate (%) to the total literates Female literacy rate (%) to the total literates Average Male Literacy to the total population (%) Average female Literacy to the total population (%) Total Literacy rate (%) to the total population Source: District Census Hand Book 2011 VIMTA Labs Limited, Hyderabad C3-58

103 Chapter-3 Baseline Environmental Status The percentage of male literates to the total literates of the study area works out to be 50.13%. The percentage of female literates to the total literates, which is an important indicator for social change, is observed to be 49.87% in the study area as per 2011 census records Occupational Structure The occupational structure of residents of work participation rate in the study area is studied with reference to main workers, marginal workers and nonworkers. The main workers include 10 categories of workers defined by the Census Department consisting of cultivators, agricultural laborers, those engaged in live-stock, forestry, fishing, mining and quarrying; manufacturing, processing and repairs in household industry; and other than household industry, construction, trade and commerce, transport and communication and other services. The marginal workers are those workers engaged in some work for a period of less than six months during the reference year prior to the census survey. The non-workers include those engaged in unpaid household duties, students, retired persons, dependents, beggars, vagrants etc.; institutional inmates or all other non-workers who do not fall under the above categories. Total work participation in the project study areas is 41.78% and the non-workers constitute 58.22% of the total population respectively. The distribution of workers by occupation indicates that the non-workers are the predominant population. The main workers to the total workers are 84.67% and the marginal workers constitute to 15.33% to the total workers. The occupational structure of the study area is shown in Table TABLE OCCUPATIONAL STRUCTURE Particulars NELP Block Area Total Population Total workers Work participation rate (%) Total main workers % of main workers to total workers Marginal workers % of marginal workers to total workers Non-workers % of non-workers to total population Source: District Census Hand Book-2011 VIMTA Labs Limited, Hyderabad C3-59

104 Chapter-4 Impact Assessment and Mitigation Measures 4.0 IMPACT ASSESSMENT AND MITIGATION MEASURES This chapter presents the identified environmental impacts due to the proposed exploratory drilling and proposed mitigation measures for minimizing or avoiding adverse impacts as well as other best practices. The proposed mitigation measures will be implemented during exploratory activities. 4.1 Impact Assessment Generally, the environmental impacts can be categorized as either primary or secondary. Primary impacts are those, which are attributed directly by the project and secondary impacts are those, which are indirectly induced and typically include the associated investment and changed patterns of social and economic activities by the proposed action. The drilling programme can be considered as a temporary activity which lasts for about 4-5 months at each well location. No above ground permanent structure, except the well head will be built at the well locations during the exploratory drilling phase of the project. The well site once drilled will be temporarily suspended / permanently abandoned based on the success and the rig will be moved to next location. Anticipated impacts from the proposed project can be classified into the following phases: a) Well site and Access Road construction Impacts from location of drill sites on land-use, aesthetics, vegetation and drainage pattern; Impacts on vegetation and soil from site clearance; Impact on ambient air from fugitive dust and vehicular exhaust emissions; Impact on soil from construction activities; Impact on socio-economics from local employment and use of local resources; and Impact on local community from temporary land acquisition, noise and disturbance. b) Drilling Operation Impacts from handling and disposal of drill cuttings and waste drilling mud; Impact on ambient air from DG set and vehicular emissions; Impacts from wastewater generation during drilling and camp site operations; Impacts from noise generating equipments e.g. DG sets, land rig and vehicles; Impact from transportation of material; Impact on local water resources due to use of water for drilling operations; and Impact from well testing on local environment. c) Decommissioning and Site Restoration Impacts from waste handling and management; Impacts on local drainage pattern; Potential impacts from migration of fluids in well bore; and Impact on local community (farm owner). VIMTA Labs Limited, Hyderabad C4-1

105 Chapter-4 Impact Assessment and Mitigation Measures Method of Impact Identification Both beneficial as well as potential adverse impacts may be expected on the environment from the proposed drilling activities. The impacts may be direct or indirect, short or long term and reversible or irreversible. The present environmental quality has been taken into consideration while assessing the magnitude and importance of specific impacts. The techniques used for assessment of impacts are both qualitative and quantitative. Qualitative assessment is based on historical evidence and available literature. Quantitative assessment has been carried out for potential air and noise pollution impacts, the results of which will be used for siting of well sites, i.e., by maintaining safe distances from sensitive receptors. 4.2 Anticipated Impacts from the Project The potential environmental impacts from the project are discussed in the following sections Land use and Aesthetics Impact on land use and aesthetics is expected to be from vegetation clearance, excavation, leveling and grading of the site. Thus there might be need for clearing crops and trees. As the land requirement for each drill site is quite small ( ha) compared to the large stretches of agricultural land there would be insignificant change to land use. Movement of heavy vehicles, earth moving equipments, piling of removed soil at the site periphery during construction would have aesthetic impacts Land Required for Drilling Activity Though exploratory / appraisal drilling is a temporary activity yet the period for which the land is required would depend on discovery of hydrocarbons. Approximately, 15,600 m 2 of land for drilling rig facilities would be impacted for each drill site. The actual drilling platform area would be approximately 5,200 m 2. The parcel of land would be temporarily acquired as per the applicable laws and in consultation with the land owners. Adequate compensation for loss of income from that piece of land, including crop loss, tree loss and any other direct or indirect loss as determined by the local revenue officials would be paid to the landowner. Drilling rig activities will result in disturbance and compaction of soils within a 1.0 ha zone around the drilling rig due to equipment, vehicles. Access roads to the drilling sites will also impact top soils. The total loss of soils as a result of exploration drilling with probably be in the order of 3-5 ha per well, depending on the length of access road required to access each site Topography & Drainage There would be slight change in topography at the drill site as it will be elevated from ground level to avoid storm water accumulation. The study area has hilly terrain and is almost devoid of approach roads with elevations varies from MSL 400 m to 2000 m. There would be minor changes in the natural drainage pattern at immediate vicinity of the well site. This impact would be substantially further reduced as the identification of wells sites would consider local drainage patterns in VIMTA Labs Limited, Hyderabad C4-2

106 Chapter-4 Impact Assessment and Mitigation Measures the area. Additionally the grading of the drilling site will be done keeping in mind that the existing aerial drainage flow pattern of the well site location. As drilling is a single point activity at each well location there will not be any change in subsoil drainage patterns Impacts on Soil Quality During construction the major impacts on soil would occur due to excavation, compaction due to movement of heavy equipment and levelling as well as pollution due to addition of moorum. Site preparation will entail stripping and removal of the topsoil which contains most of the nutrients and organisms that give soil a living character and productivity. This will in turn result in minor changes in soil hydrology and small changes in the topsoil structure. However, as the project design takes into account the preservation of the top soil and its subsequently use for topping up of the rehabilitated land. The impact on soil quality will be insignificant considering the mitigation measures implemented. The hazardous wastes generated from the exploratory drilling operations include drill cuttings, drilling mud, spent lube oil and waste oil (Category 2.2, 2.3, 5.1 and 5.2). Apart from the above, packaging wastes, used containers and any contaminated soil arising out of any accidental oil spillages during the Drill Rig movements and operations etc. are also expected to be generated from proposed drilling activities Soil Contamination Drilling wastes are generated during drilling operation through various geological formations to reach the reservoir that might hold the hydrocarbons. The mud used brings the rock cuttings (generated from drilling) to the surface, which along with the mud are called drilling wastes. Drilling operations are typically associated with a range of wastes such as drilling mud, used oils, hydraulic fluids and various discarded chemical products, empty drums and sacks, acids, surfactants, cement, biocides, solvents, and camp wastes. The chances of soil contamination are from the storage and handling practices of chemicals and fuels, surface runoff carrying contaminated substances. The drilling mud and the cuttings could also add to the sub surface contamination if not handled appropriately. ONGC has considered all the above aspects and have incorporated all these aspects in the well sites design Alteration of Soil Quality by Loss of Topsoil Loss of topsoil in these areas, either by mechanical removal or by erosion would alter the soil structure with resultant implications for revegetation. Measures inherent in the design of the project to minimize loss of topsoil and overburden are as follows: Topsoil suitable for supporting agriculture, removed during site clearance will be retained, stored as a berm on the edge of the well site, protected from erosion by plastic sheeting; Native vegetation, wherever appropriate will be kept at the edge of the well site as a seed bank, or replanted at an alternate location or will be used to protect/stabilize soil surfaces on slopes; VIMTA Labs Limited, Hyderabad C4-3

107 Chapter-4 Impact Assessment and Mitigation Measures On demobilization, adequate measures would be provided to facilitate regrowth and hence retention of topsoils; and Planned and systematic tree replanting program will be put in place. On consideration of the poor vegetation cover, the physical features of the proposed exploration block, the impact of drilling operations on soil quality will be insignificant. It is, however, important that mitigation measures are monitored to ensure that they are effective. Summary of impacts on soil and land use are given in Table-4.1. TABLE-4.1 SUMMARY OF IMPACT ASSESSMENT: SOIL AND LAND-USE Impact Area Nature of Impact 1 Targets/Interests 2 Magnitude and extent 3 Land Use Change in original Original land use Well sites and land use, land access roads only, degradation, small scale; reversible (partially) beneficial effect for afforestation and all weather access roads. Derogation of Soil Quality Soil Contamination Cumulative contamination with dust, surface runoff; reversible Physical effects on soils due to topsoil removal, nutrient loss; reversible Subsurface contamination due to spillage and handling of the chemicals and other waste materials, reversible(partial) Soil quality, flora and fauna, including grazing livestock Soil quality, flora Soil quality, groundwater flora and fauna and the grazing livestock Localised near sources; small contribution to existing background levels; Around the well location small scale degradation of soil quality Localised near the source of operation and could be nullified with proper house-keeping & waste management Overall Magnitude 4 Minor Minor Minor Minor 1 Description; short or long term; reversible or permanent; associated with construction, operation, decommissioning; cumulative, accidental, etc 2 Targets and interests potentially affected. 3 Adverse or beneficial; small, large, etc; very localised (sites only), local, regional national. 4 Overall significance against criteria ( minor; moderate, some significance; major) The mitigation measures inherent in the design of the well site, together with rigorous implementation of the waste management plan will ensure that significant impacts in relation to soil quality are not anticipated at the well site. VIMTA Labs Limited, Hyderabad C4-4

108 Chapter-4 Impact Assessment and Mitigation Measures Impact on Topography and Climate Impact on Topography The envisaged topographical changes would be due to the manmade structures like drilling rig and other associated structures. As mentioned previously drilling exploratory well is a short duration activity at each drilling location, typically encompassing a period of 3-4 months from land acquisition to site abandonment. The impact would therefore be localised, temporary and minimal Impact on Climate Impact on the climatic conditions from the drilling will not be significant. The maximum temperatures of the exit gas from the DG stack and flare stack will be around 300 C and 400 C respectively. In terms of total emission of green house 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 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; Emissions from possible flaring during well testing; and Emissions from vehicles. During the short period of site preparation mechanical shovels and earthmovers will be used for vegetation clearance, cut and fill and other site leveling activities. These activities could generate dust particles which will be mobilized by wind, and deteriorate the ambient air conditions. However, these activities will be only temporary and with the clay nature of the soil, the impact to ambient air quality would be within the close proximity of well site. All the anticipated air emissions other than dust arise from combustion of hydrocarbons. The pollutants of concerns are NOx, SO2, CO, Particulate, and unburnt hydrocarbons Potential Impacts Ambient air quality effects are normally assessed in relation to their potential to cause: Health deterioration and nuisance in local communities; Health deterioration amongst on-site workers; and Damage to vegetation. The gaseous emissions from the DG set will be controlled by efficient combustion of fuel in the DG set. The flaring of oil and gas during well testing is a short duration activity (about 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. VIMTA Labs Limited, Hyderabad C4-5

109 Chapter-4 Impact Assessment and Mitigation Measures The impact on ambient air quality is assessed hereunder considering the following: The air quality impacts have been predicted for the proposed drilling; and Site-specific meteorological parameters have been recorded. Short-term 24 hourly GLC's incremental values were estimated using the site-specific meteorological data Fugitive Emissions Air pollution during construction would be primarily due to fugitive emissions from vehicular movement, site preparation activities and material handling. Weathering of soil would take place as a result of clearing of vegetation, excavation and movement of heavy vehicles. The weathered soil generates dust due to reentrainment during vehicular movement and equipment mobilization. Such dust emissions as experienced in other similar construction activities are of larger that 10µ (more than respirable range) and propagates to short distances. These emissions only have nuisance factor affecting workers at site. Use of dust masks would be adequate to mitigate impacts on workers. Fugitive emissions of VOC may result from the vents from the venting of un-burnt methane from well testing. However, the testing phase will be short duration of days. Fugitive emissions in the form of material dust is expected during drilling operations (loading, unloading, handling of drilling fluid, chemical additives, cement and cement additives). Some fugitive emissions are also anticipated from storages of volatile chemicals and fuel at the site if the storages are not properly capped or are handled without due care. However, such emissions will not disperse widely and can only affect workers and people at site. Fugitive emissions during drilling operations are however not as significant as during site preparation. Fugitive emissions during drilling are not expected to travel beyond project boundaries. Workers working near fugitive emission sources are only susceptible which would be mitigated through use of PPEs in these areas Air Pollution Modeling Prediction of impacts on air environment has been carried out employing mathematical model based on a steady state Gaussian plume dispersion model designed for multiple point sources for short term. In the present case, AERMOD dispersion model based on steady state gaussian plume dispersion, designed for multiple point sources for short term and developed by United States Environmental Protection Agency [USEPA] has been used for simulations from point sources Pollutants/Model Options Considered For Computations The model simulations deal with two major pollutants viz., Sulphur dioxide (SO2) and Oxides of Nitrogen (NOx) emitted from the DG sets. Model Options Used For Computations The options used for short-term computations are: VIMTA Labs Limited, Hyderabad C4-6

110 Chapter-4 Impact Assessment and Mitigation Measures The plume rise is estimated by Briggs formulae, but the final rise is always limited to that of the mixing layer; Stack tip down-wash is not considered; Buoyancy Induced Dispersion is used to describe the increase in plume dispersion during the ascension phase; Calms processing routine is used by default; Wind profile exponents is used by default, 'Irwin'; Flat terrain is used for computations; It is assumed that the pollutants do not undergo any physico-chemical transformation and that there is no pollutant removal by dry deposition; Washout by rain is not considered; Cartesian co-ordinate system has been used for computations; and The model computations have been done for 10 km with 1000-m interval Model Input Data Emissions from DG Stacks Air pollution from point sources at the drill site will be primarily contributed by the DG sets. Drilling requires a considerable amount of electric power and as a result will need the installation of DG sets which can supply around 2250 KVA of power at peak periods. The primary pollutants emitted by DG Sets consist of Oxides of Sulphur and Nitrogen, Carbon monoxide, Carbon dioxide and Hydrocarbons. Combustion of fuel in a DG set typically happens at high temperatures resulting in generation of considerable amounts of NOx. The SO2 concentration in emissions is dependant on the Sulphur content in fuel burnt and particulate matter consists of unburnt Carbon particles. The emission from each of the power generator sets in the drilling rig will be due to combustion of diesel. For a particular drilling site during drilling operation, there will be 3 operating DG sets, as detailed in Table-4.2. TABLE-4.2 DETAILS OF DG SETS Location DG Capacity Operational Stand by Fuel Requirement Drilling Site 750 KVA 3 1 HSD 5KL/day The operational DG sources are considered as source for the modeling. The emission from each of these diesel generators will be due to combustion of diesel. Emissions from Flare Stack Another major source of emission from a single point is flaring pit. Flaring will be conducted only in the event of a hydrocarbon discovery. Flaring will be avoided as far as practicable for liquid hydrocarbons as these would be collected for surface testing and transported to legally approved entities. There is maximum probability of only gas being flared from a specially designed pit. Though flaring is a point source yet the dispersion of emission starts at the ground level as it would be carried out in a pit. Flaring of gases is a high combustion process which generates nitrogen oxides as pollutant. There are negligible quantities of particulates, Sulphur dioxide or other pollutant. Improper flaring may however lead to escape of unburnt hydrocarbons (primarily) CH4. VIMTA Labs Limited, Hyderabad C4-7

111 Chapter-4 Impact Assessment and Mitigation Measures Modelling Scenarios Emissions from diesel generator sets will be continuous throughout the drilling operations. The main pollutants from diesel generator sets include NOx and SO2 while NOx is the main pollutant expected to emit from test flare. As the fuel used is low sulphur HSD, insignificant amount of particulate emissions and gaseous emissions are envisaged. Similarly, during flaring also, particulate emissions are negligible. The emission characteristics considered for the modeling exercise from DG generator sets and test flaring are given in the Table 4.3. The emission rate calculations for air dispersion modeling are given in Annexure-VII. TABLE-4.3 EMISSION CHARACTERISTICS-MODEL INPUTS Sr. No Particulars DG Set (3 x 750 KVA) 1 No of engines and stacks 3 2 Height above ground level (m) Diameter (m) Gas temperature ( 0 C) Gas velocity (m/s) 15 6 Emission rate (g/s) - Sulphur dioxide - Oxides of Nitrogen Presentation of Results Model simulations was carried out for pollution SO2 and NOx. The results for SO2 and NOx [1 st maximum] are presented in Table-4.4. The isopleths for SO2 and NOx concentrations are depicted in Figure-4.1 and Figure-4.2. TABLE-4.4 PREDICTED 24-HOURLY SHORT TERM INCREMENTAL CONCENTRATIONS Season Winter & premonsoon SO 2 NO x Maximum Incremental Conc. (µg/m 3 ) Distance (km)/ Direction Maximum Incremental Conc. (µg/m 3 ) Distance (km)/ Direction , N , N Comments on Predicted Concentrations A perusal of Table-4.4 reveals that the maximum incremental short term 24 hourly ground level concentrations for SO2 and NOx likely to be encountered due to DG sets are 3.1 µg/m 3 and 4.6 µg/m 3 occurring at a distance of 1.0 km in north direction. The predictions indicate that the SO2 and NOx concentrations are likely to be well within the prescribed limit for residential and rural zone. Based on the above it can be inferred that the ambient air quality in the study area is unlikely to be affected due to the proposed drilling. VIMTA Labs Limited, Hyderabad C4-8

112 Chapter-4 Impact Assessment and Mitigation Measures Resultant Concentrations After Implementation of the Project The maximum incremental GLCs due to the proposed project for SO2 and NOx are superimposed on the maximum baseline SO2 and NOx concentrations recorded during the study to arrive at the likely resultant concentrations during winter season after commissioning of the proposed drilling. The cumulative concentrations (baseline + incremental) after implementation of the project are tabulated below in Table-4.5. TABLE-4.5 RESULTANT CONCENTRATIONS DUE TO INCREMENTAL GLC's Pollutant Maximum AAQ Concentration Recorded During the Study Incremental Concentration due to drilling Resultant Concentration SO NOx All values are in g/m 3 The maximum GLCs for SO2 and NOx after implementation of the proposed project are likely to be within the prescribed standards for rural and residential areas. However, the maximum GLCs are occurring during test flaring which is for a period of days at each location. Further considering that the maximum GLCs occur at about 1.0 km, which is in the vicinity of the site boundary, no impact on outside environment is envisaged. Based on the above details, it can be inferred that the ambient air quality in the study area is unlikely to be affected due to the proposed activity. VIMTA Labs Limited, Hyderabad C4-9

113 Chapter-4 Impact Assessment and Mitigation Measures FIGURE-4.1 SHORT TERM 24 HOURLY GLCs OF SO2 VIMTA Labs Limited, Hyderabad C4-10

114 Chapter-4 Impact Assessment and Mitigation Measures FIGURE-4.2 SHORT TERM 24 HOURLY GLCs OF NOx VIMTA Labs Limited, Hyderabad C4-11

115 Chapter-4 Impact Assessment and Mitigation Measures Impact on Surface Water and Groundwater Quality The study area is having small tributaries river system. The block area is drained by some small tributaries. Location of well sites near to the rivers and major water bodies is however ruled out and thus any direct impact on water bodies is not anticipated. Therefore considering the water availability and abundant sources, there would be insignificant impacts on water resources due to usage in the project. Surface water quality in the region has been found to be of good quality and is being used by villagers for irrigation and other domestic purposes. Ground water in the region is potable in nature Sources of Pollution In general circumstances, the surface water impacts that could be potentially caused from the drilling activities are as follows: Withdrawal of groundwater; Accumulation of the wastewater in the drilling site; Potential wastewater discharges may arise from the following sources: o o o o o o Treated domestic effluent (sewage and kitchen waste); Spent drilling muds, cuttings and completion fluids disposal; (Potentially) contaminated storm water drainage from the derrick floor and other systems; Seepage of drilling mud fluid into subsoil from mud collection & recirculation pond; (Potentially) high sediment loads in runoff from unpaved well site areas during heavy shower; and Any produced water and liquid hydrocarbon fractions collected in the test separator during well testing. Potential accidental spills of fuel, lubricants or chemicals and leaks from engines (i.e. power generators, vehicles) and liquid hydrocarbons during testing; and Waste handling particularly spent lubricants and chemicals during disposal may give rise to accidental releases Potential Surface and Groundwater Impacts Based on the above-mentioned activities, the following potential impacts have been identified: Potential for water logging during monsoon in the site; Potential for adverse impact on the surface water quality; Potential for adverse impact on the groundwater quality; and Likely change in the aquifer potential within the study area. VIMTA Labs Limited, Hyderabad C4-12

116 Water Pollution Environmental Impact Assessment Report for Proposed Exploratory Drilling of 2 Chapter-4 Impact Assessment and Mitigation Measures Process Wastewater Approximately m 3 /day of wastewater would be generated from the drilling operation including minor quantities from washing and cleaning of rig floor and other equipments. Water based drilling mud is non-hazardous in nature. The primary pollutants in the wastewater would thus be suspended solids, dissolved solids and traces of floating oil from washing of rig floor and other equipments. Effluents can cause significant pollution to water bodies especially ponds and lakes if disposed untreated. However, the wastewater will be collected in lined pits and clarified wastewater will be treated in packaged treatment plant located at the well sites to meet norms specified by CPCB and MPCB for discharge to land and surface water bodies. Sewage It is estimated that approximately 8 m 3 /day of sewage will be generated from each well site. The sewage will be discharged into septic tanks and then to subsoil through soak pits. The subsoil in the area is found to be rich in organic content and micro-organisms. No impacts are thus envisaged from sewage disposal from site. Pollution Potential from Surface Runoffs As the area experiences high rainfall, the site will generate considerable volume of runoffs during such rainy periods. The storm water generally contains high concentration of suspended matter eroded from the soil by the runoff. There is also a potential for contamination of the storm-water if the runoff picks up contaminants in the form of chemicals, oil and lubricants, etc. that could have been spilled or if material is stored in open areas (uncovered) in any particular area like the fuel storage or the non-hazardous chemical storage areas. This may result in a potential impact to the receiving water body. Potential Impacts on Ground Water and Hydrogeology There is a probability that during excavations, especially if conducted immediately after monsoon may lead to development of springs which may have to be dewatered. Reduced Infiltration The compaction of the working areas for setting up heavy machineries and equipments like the rig may lead to increased runoff and reduced infiltration, thereby affecting localised subsurface groundwater recharge. However, given that the occupation of the area is temporary and the area experiences high rainfall and thereby high recharge potential, the effect on the groundwater regime of the area will not affect water availability in neighbouring wells and tube wells and any resulting conflict with other users of groundwater in the area. VIMTA Labs Limited, Hyderabad C4-13

117 Chapter-4 Impact Assessment and Mitigation Measures Impact to Surface Water Quality The probability of contamination of surface water bodies and sub-surface water bodies was discussed above. The impact to the surface water bodies could arise from discharge from the site, disposal practice of spent drilling mud, cuttings, completion fluids, handling of liquid hydrocarbons, fuels etc. With the proposed concrete pavement and secondary containment provisions, the surface water quality contamination will be negligible. Noticeable impacts to water quality in nearby watercourses are more likely to occur as a result of increased suspended particle load. During the well site preparation the extent of impact to nearby watercourses will be function of: Area cleared; Amount of rainfall from the period between site construction and drilling; Distance of the watercourse from the well site; and Mitigation measures to prevent any soil erosion within well site. However, if the site preparation activities were conducted in dry season, the above impact would be negligible or insignificant. Overall, with the appropriate measures to protect the well site and prevent discharges, installation of soil erosion control measures, prevention of spillages while handling and management of chemicals, the likely chances of impact on surface water will be minor Impact on Groundwater Regime The water is used for preparing drilling mud and for domestic needs of the campsite. The water requirement is primarily depended upon the depth of the proposed well and time required for the drilling the well. The drilling fluid will be recycled and fresh water will be used as makeup water and for general washing and daily maintenance. The water requirement is proposed to be met from the local sources through water tankers. Since the drilling activity being temporary and water requirement is meager, no adverse impact on ground water resources is envisaged. ONGC is using water based non-toxic biodegradable fluids with inhibitive and encapsulative characteristics as drilling mud. Additionally, the drilling mud collection and recirculation pond is lined with impervious layer to prevent seepage and loss of drilling fluid into the subsoil. Further, proper casing installation and cementing will ensure least groundwater contact. Apart from the mud characteristics, the waste and spent mud would be disposed in polyethylene propylene lined pits for all the storage areas as per the EHS Management Plan Civil works. The mud components during the storage form a bentonite (clay) lining along the pit wall preventing the seepage of water to the underground strata. Any hydrocarbons contamination will be skimmed off from site before proceeding to the next site so as to ensure that no leaching or subsurface contamination finally reaches the groundwater table. The waste oils and the skimmed oils collected from the drill site will be sent to the MPCB authorized recyclers. Overall, with the appropriate management practices in place impacts on groundwater quality at the site is likely to be insignificant. The summary of impacts on water resources is given in Table-4.6. VIMTA Labs Limited, Hyderabad C4-14

118 Chapter-4 Impact Assessment and Mitigation Measures TABLE-4.6 SUMMARY OF IMPACT ASSESSMENT: WATER RESOURCES Impact Area Nature of Impact 1 Targets/Interests affected 2 Surface Water Physical Long term Local inhabitants Impact Chemical Impact modification to the distribution of rain water catchment, if located near it Short term due to increase in siltation load of the water bodies in rainy season Short term contamination of surface water flows due to untreated effluent, run-off, seepage from water holding tanks etc., depending on the water harvesting for water Localized impact to surrounding Rivers and adjoining the water bodies in monsoon Localised impact to surrounding nallahs and the river bodies in monsoon Magnitude and extent 3 Overall significance 4 Local, could be Minor mitigated by avoiding water harvesting areas Regional, and for short term Local, small scale mitigated by well site design and operations Moderate Minor Ground Water Groundwater quantity Long term Could also result in sub Regional, dependent Moderate contamination in the surface contamination on occurrence of region due to surface around the region flood. Good runoffs from well engineering. sites during flash practices will reduce floods risk of flooding and overflow Long & medium term, reduction due to percolation of subsurface contamination Shallow aquifers surrounding the well sites Local/Regional Minor possibility remote with mitigation measures Resource Management Resource Long term, medium Judicious abstraction of Regional, Can be Minor Management reduction water for usage mitigated by sourcing water from water surplus catchment areas. Drill site borewell can be used by locals after drilling, if water quality is acceptable 1 Description; short or long term; reversible or permanent; associated with construction, operation, decommissioning; cumulative, accidental, etc 2 Targets and interests potentially affected. 3 Adverse or beneficial; small, large, etc; very localised (sites only), local, regional national. 4 Overall significance against criteria ( minor; moderate, some significance; major) Impact on Noise Levels Sources During the drilling operation at the well sites, there would be various sources of noise in the area. These sources would be: VIMTA Labs Limited, Hyderabad C4-15

119 Chapter-4 Impact Assessment and Mitigation Measures Drilling draw works/rotors; Mud Pumps; Power generators; Vehicular Movement; and Cranes and material handling equipment Potential Impacts Ambient noise quality is normally assessed in relation to its potential to cause: Health deterioration and nuisance in local community; Health deterioration amongst on-site workers; and Disturbances and fragmentation to local habitats Assessment of Noise Impacts due to Site Activities Driller rotors and the power generators and pumps would be the main sources of noise pollution during the drilling activity. Noise due to vehicular movement will be intermittent, but will also add to the background noise levels. The well site during excavation phase of the site preparation where heavy earth moving machinery will be in operation, noise level of the vehicle should not be more than the 90 db (A). Typically, the noise generating sources for the onshore drilling activity are provided below (in the immediate vicinity) Diesel Generator : 90 to 95 db(a) Pumps at the Rig : 85 to 90 db(a) Miscellaneous : 80 to 85 db(a) Control Room & Quarters : 50 to 60 db(a) In order to predict ambient noise levels due to the proposed drilling the preparative modeling has been done. For computing the noise levels at various distances with respect to the plant site, noise levels are predicted using an user friendly model the details of which is elaborated below Details of Noise model Mathematical Model for Sound Wave Propagation During Operation For an approximate estimation of dispersion of noise in the ambient from the source point, a standard mathematical model for sound wave propagation is used. The sound pressure level generated by noise sources decreases with increasing distance from the source due to wave divergence. An additional decrease in sound pressure level with distance from the source is expected due to atmospheric effect or its interaction with objects in the transmission path. For hemispherical sound wave propagation through homogenous loss free medium, one can estimate noise levels at various locations, due to different sources using model based on first principles, as per the following equation: Lp2 Lp1 20 log(r (1) 2 /r 1 ) VIMTA Labs Limited, Hyderabad C4-16

120 Chapter-4 Impact Assessment and Mitigation Measures Where Lp2 and Lp1 are Sound Pressure Levels (SPLs) at points located at distances r2 and r1 from the source. The combined effect of all the sources then can be determined at various locations by the following equation. L p( total) ( L p1 /10 ) ( L p2 /10 ) ( L p3 /10 ) 10Log( ) (2) Where, Lp1, Lp2, Lp3 are noise pressure levels at a point due to different sources. Based on the above equations an user friendly model has been developed. The details of the model are as follows: Maximum number of sources is limited to 200; Noise levels can be predicted at any distance specified from the source; Model is designed to take topography or flat terrain; Coordinates of the sources in meters; Maximum and Minimum levels are calculated by the model; Output of the model in the form of isopleths; and Environmental attenuation factors and machine corrections have not been incorporated in the model but corrections are made for the measured Leq levels Input for the Model The incremental increase in noise levels due to the operation phase of the exploratory drilling has been done. Noise levels are mainly generated from DG sets, air compressors, pumps and transformers. The noise sources have been defined with respect to center of drill site. The input data pertaining to corresponding noise level are tabulated below in Table-4.7. TABLE-4.7 INPUT DATA FOR NOISE MODELING Sr. No. Location Noise Levels db(a) 1 Diesel Generator sets 90 to 95 2 Pumps and the rig 85 to 90 3 Miscellaneous 80 to 85 4 Control Room and Quarters 50 to Presentation of Results The model results are discussed below and are represented through contours in Figure-4.3. The predicted noise level at 100 m distance from the boundary of well site is 52.0 db (A) and are tabulated in Table-4.8. TABLE-4.8 PREDICTED NOISE LEVELS Sr. No. Distance from well site boundary Noise Level, db(a) 1 25 m m m m 52.0 VIMTA Labs Limited, Hyderabad C4-17

121 Observation Environmental Impact Assessment Report for Proposed Exploratory Drilling of 2 Chapter-4 Impact Assessment and Mitigation Measures Occupational Health Hazards from Noise Pollution Exposure to noise levels, above Threshold Limit Value (TLV), has been reported to have detrimental effect on the workers' health. Personnel s working for more than 4 to 4.5 hours per shift near the sound pressure level of 90 db(a) will be greatly affected, unless suitable mitigatory measures are taken. The adverse effects of high noise levels on exposed workers may result in: Annoyance; Fatigue; Temporary shift of threshold limit of hearing; Permanent loss of hearing; and Hypertension and high blood cholesterol, etc. Noise pollution poses a major health risk to the workers near high noise source. If the magnitude of noise exceeds the tolerance limits, it is manifested in the form of discomfort leading to annoyance and in extreme cases to loss of hearing. Detrimental effects of noise pollution are not only related to sound pressure level and frequency, but also on the total duration of exposure and the age of the person. Table-4.9 below gives noise levels and associated mental and physical response of humans. TABLE-4.9 NOISE EXPOSURE LEVELS & ITS EFFECTS Noise Levels (db(a)) Exposure Time Effects 85 Continuous Safe Continuous Annoyance and irritation Short term Temporary shift in hearing threshold, generally with complete recovery Above 100 Continuous Permanent loss of hearing Short term Permanent hearing loss can be avoided Several years Permanent deafness Few months Permanent deafness 120 Short term Extreme discomfort 140 Short term Discomfort with actual pain 150 and above Single exposure Mechanical damage to the ear Source: OSHA During drilling operation, the personnel required to continually present in high noise source like DG is remote. All personnel working on rig are given noise abatement personnel protective equipments like earmuffs etc. VIMTA Labs Limited, Hyderabad C4-18

122 Chapter-4 Impact Assessment and Mitigation Measures FIGURE-4.3 NOISE LEVEL CONTOURS VIMTA Labs Limited, Hyderabad C4-19

123 Chapter-4 Impact Assessment and Mitigation Measures Community Noise Level The maximum predicted noise level at about 100 m from the boundary of the drill site is about 52.0 db(a). The ambient noise levels at most of the places in the region are within the CPCB standards. Since, the drilling operations last for only 3-4 months at each location, impact of the noise pollution due to the proposed exploratory drilling will be insignificant on the community. It can be concluded that the impact due to elevated noise is confined only up to a distance of 100 m from the drilling point and in areas beyond this distance, the ambient noise levels are within the stipulated ambient noise quality norms Ecological Impacts Impact on the ecology of the study area will vary with the proximity of the habitats from the drilling locations. However, the impacts are of temporary nature, which will last only for few months at each drill location during the exploratory drilling activities and will thus allow subsequent recovery after the activities stops. The block area is mostly confined in amidst agrarian habitations comprising of paddy fields dotted with few betel nut trees and cash crop of tea gardens in the homesteads. Considering the above aspects the chance of irreversible ecological impact at the exploration stage is minor. The primary form of impact could be in form of habitat disturbances, which would normalize after completion of the drilling activity. During the site preparation activities vegetation clearance would be nominal or minor. Efforts will be made to avoid areas of comparatively dense vegetation cover, unless absolutely essential. The land use in the block area is predominantly devoid and forest area. Efforts will be made to avoid areas of comparatively dense vegetation cover, unless absolutely essential. The impact predictions based on the air dispersion modelling found to be well within the prescribed standards. Hence, the impact on ecology will be negligible. The flora and faunal habitats in the study area may be affected by erosion, siltation and water stagnation arising from run-on and runoff at the well site, if suitable mitigative measures are not implemented. The mitigative measures pertain to surface run-off from well site, wastewater discharges, solid waste disposal, erosion abatement measures, etc; As long as strict environmental management measures are put in place, including adequate measures for supervision of contractors and staff, negative effects on fauna will be minimised. There are, however, likely to be some residual, unavoidable, impacts, linked to the requirement of optimal clearing the vegetation to facilitate drilling activities. The summary of impact on flora and fauna are given in Table VIMTA Labs Limited, Hyderabad C4-20

124 Chapter-4 Impact Assessment and Mitigation Measures TABLE-4.10 SUMMARY OF IMPACT ASSESSMENT: FLORA AND FAUNA Aspect Nature 1 Targets/Interests 2 Loss of habitat Loss of vegetation land Flora and fauna, flora typically type vegetation, faunal comprise grazing animals and dependent mammals and reptiles. Magnitude 3 and extent Small & localised. Overall Significance 4 Minor Disturbance Light, noise. Surface run-off. Project duration only Local community, Breeding birds, and flora and other fauna. Small, localized. Mitigative measures in-built in equipment /well site design to meet ambient limits. Moderate Flaring would cause disturbance of transient nature for a very short duration Invading Colonisation by Avifauna and fauna Small, Localised. No Minor species species associated migration route / with human activity paths reported in the block. Waste Contaminated Fauna, especially Small, Localised. No Minor disposal/ runoff water/rain water, birds and reptiles off-site disposal is likely to occur from the exploratory drilling operation. Area fenced and maintained even after drilling operation completed 1 Description; short or long term; reversible or permanent; associated with construction, operation, decommissioning; cumulative, accidental, etc 2 Targets and interests potentially affected. 3 Adverse or beneficial; small, large, etc; localised (sites only), local, regional national. 4 Overall significance against criteria ( minor; moderate, some significance; major) Impact on Socio-Economic Aspects Although the well site would be selected to avoid any major social impacts, there will, nevertheless, be some issues that need to be addressed in the region. The drilling programme would involve setting up the actual drilling rig, construction of campsite for accommodation and operational crew. An approach road from the road head to the drilling rig will also be developed and also to facilitate regular transport from campsite. It is anticipated that the drilling activity would involve direct and indirect impacts on socio-economic environment. These impacts are short term in nature. ONGC proposes to avoid any settlements, there is expected to be no displacement of people for the proposed drilling campaign. The well sites are expected to be in non-residential lands/ human settlement zones. VIMTA Labs Limited, Hyderabad C4-21

125 Chapter-4 Impact Assessment and Mitigation Measures The types of impacts due to drilling activities have been summarized below: Land required for drilling activity Partial loss of productivity of land due to the project Temporary losses during the drilling activity Common Property Resources Demography and Socio-Economics Impact on Civic Amenities The area has limited network of roads and communication in the village areas. Many villages have been electrified during the last decade. There are few business centers and industrialized zones in the project block area, covered in both the districts. Although, the level of existing communications and support services in the area are considered adequate based on the population density, establishment of the proposed project would be a distinct beneficial impact. The overall impact is considered to be positive Impact on Health Impact on health due to emissions and noise from drilling activity has been assessed to be minimal. In addition employees working at the drill site would be provided protective devices like ear plugs/ear muffs for ensuring minimum impact on human health Social well being At the camp sites, while communication between locals and outside workers may sometimes be good (exchange of information about places and lifestyle) there is a risk that an influx of migrant population from outside areas could well lead to social tensions. As a general rules, base campsites would be located away from centers of population in order to minimize these risks. Development and exploration drilling programme is expected to generate local employment in the order of 50 to 80 unskilled and semi- skilled people, for a period of approximately 3 4 months at each drilling site location. While this benefit is small by most standards, it is a significant employment opportunity in the block Impact due to Vehicular Movement The anticipated traffic volume during the construction phase of about 30 days, would approximately be 30 truck loads per day of material movement. The installation of the drill site equipment / facilities involves about 80 trailer loads spread over 10 days and during regular drilling operations on an average 5 truck movements per day with 10 small vehicles for the visitors and the drilling team would take place. Considering the sparse vehicular movement in the block as a whole, the above anticipated traffic volume and the resulting emissions will be well within the stipulated ambient air quality norms. VIMTA Labs Limited, Hyderabad C4-22

126 Chapter-4 Impact Assessment and Mitigation Measures Other Impacts on Resources and Infrastructure As highlighted earlier, infrastructure is very scarce in the study area, especially in the vicinity of the proposed well sites. Preparation and drilling operations could conceivably affect the following infrastructure Glare from Flaring During well testing, flaring will take place continuously for days period. This activity will cause a significant change in the background levels of light due to glare in the local vicinity of the site, especially during the night, during the period of flaring. There will be some impact on the surrounding fauna and habitat whose living patterns will be disturbed significantly, due to the glare during the flare testing. Given that the duration of the flare testing will be relatively short, it is anticipated that the impact will be of temporary nature with no residual impacts after the well testing has been completed. Nevertheless, ONGC will fore warn the communities in advance of well testing. Exploratory drilling is a temporary activity which lasts for about 3-4 months at each location. Thus, the environmental impacts are transient in nature and there will not be any residual impact on the environment. 4.3 Environment Management Plan The objective of the Environmental Management Plan (EMP) is to identify project specific actions that will be undertaken to mitigate and manage impacts associated with the proposed drilling programme. In view of the proposed exploratory drilling project, the adequacy of the proposed pollution control measures has been analysed to meet the standards and norms of concerned authorities. The EMP reflects statutory requirements, ONGC s own corporate operational guidelines for onshore hydrocarbon exploration and development projects. Cognizance has been taken of all the applicable standards and guidelines (amongst others) in the preparation of the EMP. The following sections discuss the mitigation measures for each potential effect. Actions and monitoring requirements are summarized Table The Environmental Management Plan (EMP) describes both generic good practice measures and site specific measures, the implementation of which is aimed at mitigating potential impacts associated with the exploratory drilling in the AA- ONN-2009/3 block Environmental measures during well construction i. As a preventive measure to avoid impacts the well site will be located based on the following consideration: Located at least m away from the nearest village habitat / sensitive receptors; Located at least the height of the well mast away from public road; Located at least m away from existing water bodies; VIMTA Labs Limited, Hyderabad C4-23

127 Chapter-4 Impact Assessment and Mitigation Measures ii. iii. iv. Ensure natural drainage channels are avoided or drainage channels rerouted to ensure unhindered flow of rain / flood water. Where necessary adequate erosion control measures will be provided; Located in a manner to avoid plantations of timber yielding trees Construction activities will be coordinated in consultation with landowners and local authorities to reduce interference with agricultural activities. In dry weather conditions, water sprinkling during excavation, levelling and transportation will be implemented. Topsoil will be stripped below plough depth from the well site and stored on the site. The depth of stripping will be on the basis of site specific soil survey. Topsoil will also be stripped from and stored adjacent to the site. v. The well site ground level will be raised and hard standing provided. Drainage channels around the site area will be constructed to ensure no obstruction to flow pattern. vi. vii. viii. ix. The approach roads will be routed in a manner so that disturbance to existing activity and to the local community is minimized. Routing through village habitat areas will be avoided, as far as practical. The road surface will be maintained to minimize generation of vehicular movement dust in the local area. The drill site would be provided with sufficient and suitable sanitary facilities and these will be connected to well designed and maintained septic tanks. Hazardous materials such as diesel, lubrication oil and paint materials required at the site during construction activities would be stored and disposed as per hazardous waste authorisation conditions. To ensure that the local inhabitants are not exposed to the hazards of construction the site would be secured by fencing and manned entry posts. x. The chemical and diesel storage area will be paved and provided with spill containment walls. Pits for storage of water, drilling mud and drill cuttings will be provided with impervious liner. Sufficient free-board will be provided to prevent overflow. xi. It would be ensured that diesel powered construction vehicles are properly maintained. Vehicle maintenance would be carried out authorised service centres. Service centres will be so selected to ensure that these conform to statutory regulations Soil Erosion Well site design and planning incorporates certain best practices principles such as grading and levelling of ground and ensuring the local drainage patterns are disturbed to the minimum, minimum clearance of vegetation, restoration of topsoil and drainage system to minimize the soil erosion. Efforts will be taken up VIMTA Labs Limited, Hyderabad C4-24

128 Chapter-4 Impact Assessment and Mitigation Measures to reduce long-term soil erosion and loosening of the soil in the site preparation activities. With the adequate management plan for restoration of the soil cover and proper management plan the impact on soil erosion will be minimized. Soil Contamination ONGC also has a detailed waste management plan to ensure safe disposal practices and minimize potentiality of soil or sub surface contamination. Some of the specific measures included in the management plan are: Only effluent from treated sewage (septic tank system) will be discharged to the local environment; The clarified waste water will be collected in lined pits and treated through packaged treatment plant for oil and suspended solids removal to ensure that it meets land or water discharge standards depending on discharge point; Spent lubricants and other waste or unused materials will be removed from site as soon as is practicable (and certainly prior to leaving the site) for appropriate off-site disposal or use elsewhere; An inventory will be maintained of all fuel, lubricants and chemicals stored on the site. Oil and chemicals, will be stored in dedicated paved and contained areas; Waste oil resulting from equipment lubrication will be stored and handled as per the provisions of the Hazardous Waste (Management, Handling & Transboundary Movement) Rules, 2008; and Implementation of the waste management plan actions as described in the earlier points are subjected to regular audits to ensure effectiveness All oil handling and storage areas will be provided with concert paving and secondary containment. The impact on surrounding soils from any accidental fuel spills will depend upon the season and the nature of the spillage. During the dry season, small spills are likely to cause only localized impact on soil. During the monsoon season, however, when surface soils are likely to be water saturated, pollutants are more likely to travel along the surface as runoff. Oil spill response plan will be put in place including the provision of absorbents and in case of unlikely event of a significant spill, soil remediation measures will be taken to clean up the contaminated area Removal of Equipment and Materials In the event that economic quantities of hydrocarbons are found, the well will be suspended with a wellhead in place, but all other equipment and materials will be removed from the site. All empty drums, wastes, used and unused drilling fluids, fuel and lubricants will be removed from the drilling site. Water supply and effluent discharge hoses and associated equipment will be removed. The access road(s) would be reinstated. VIMTA Labs Limited, Hyderabad C4-25

129 Chapter-4 Impact Assessment and Mitigation Measures Restoration of Cutting Containment Area At the conclusion of well testing at each drilling site, the lined pits of drilling wastes will be covered with soil and left onsite. All these sites will be fenced as per the HSE Management. With appropriate lining of the pit in place, it therefore does not pose any environmental hazard Restoration of Well Sites Grading will take place to ensure natural runoff. Any remaining topsoil that has been stocked during site clearance will be re-spread over appropriate portions of the site. All efforts will be taken to restore the land suitable for pre-project land use condition Decommissioning upon Abandonment In the event that no economic quantities of hydrocarbons are found, a full abandonment plan will be implemented for the drilling sites in accordance with the applicable Indian petroleum regulations. The overriding principle being that the environment should is reinstated to broadly to its original condition. Until such time as this is achieved, ONGC would actively manage the reinstatement process. All concrete or steel installations would be removed to atleast 1 m below ground level so as to ensure that there are no protruding surface structures. In the unlikely event that soil is found to be contaminated, measures would be taken to remove or treat appropriately all contaminated topsoil to promote its remediation Atmospheric Emissions Other potential sources of emissions which can cause impacts on environmental components are gaseous emissions and noise pressure levels at the rig. The gaseous emissions would routinely be contributed by D.G. sets deployed for power generation. But in this project, diesel with low sulphur content will only be used. The incremental concentrations of SO2 and Oxides of Nitrogen due to the operation of DG sets and flaring will be negligible. There will be no sensitive receptors to the emissions of combustion products in the vicinity of the proposed drilling operations apart from the crew of the drilling rig. The impacts caused are therefore, considered to be negligible. Measures to ensure minimal impacts include: Appropriate management of DG sets to achieve fuel efficiency and therefore reduce emissions; Use of low sulphur diesel oil (<0.05% sulphur content) if available; Environmental monitoring during drilling and well testing to ensure compliance to the standards ; 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 VIMTA Labs Limited, Hyderabad C4-26

130 Chapter-4 Impact Assessment and Mitigation Measures Prior to flaring, the critical equipment such as burners, anti glare accessories will be thoroughly tested Noise Environment The modeling results show that the noise levels will attenuate to below permissible levels within the drilling site boundary. However, the following measures that already exist on the drilling rig will be followed. Generators will be properly enclosed; The exhausts will be provided with silencers; and Operators/personnel working near the noise sources at the DG sets of drilling rig will be provided with earmuffs and earplugs Management of Drilling Wastes The major waste product of a drilling operation is the generation of rock cuttings with residual mud adhering to the drill cuttings and spent drilling fluid. About m 3 drill cuttings per well and 40 m 3 /day spent drilling fluid would need to be disposed off. Following measures to be adopted for disposal of drill cutting and residual drilling fluids: Drill cuttings separated from WBM should be properly washed and unusable / residual drilling fluids WBM should be disposed off in a well designed pit lined with impervious liner located offsite or on sit. The chemical additives used for preparation of DF should have low toxicity i.e 96 hr LC50 > 30,000 mg/l as per mysid toxicity or toxicity test conducted on locally available sensitive species. The chemicals used (mainly organic constituents) should be biodegradable. The waste pit after it is filled up shall be covered with impervious liner, over which, a thick layer of native soil with proper top slope is provided. Drilling wastewater including DC wash water should be collected in the disposal pit evaporated or treated and should comply with the MPCB discharge standards. Barite used in preparation of DF shall not contain Hg>1 mg/kg & Cd>3 mg/kg. Total material acquired for preparation of drill site must be restored after completion of drilling operation leaving no waste material at site. MPCB should be informed about the restoration work. The proposed control measures include: Use of water based drilling mud; only in case of problem due to geological formation Synthetic Based Mud would be used. Proper washing and disposal as per MOEF guidelines vide GSR 546 (E) would be adhered to in case of use of SBM. VIMTA Labs Limited, Hyderabad C4-27

131 Chapter-4 Impact Assessment and Mitigation Measures Mud recovery from cutting during drilling and recycling of drilling fluid; Management of drill fluid losses as part of the standard operational procedures of the drilling rig; Impervious layer lined storage pond for the storage and recycling of drilling mud; Drill cuttings to be stored in impervious lined drill cutting pits; and Drill cutting and spent drilling fluid to be treated with flocculant and liquid fraction solar evaporated. The solids to be solar dried and covered with an impervious lining and buried in a lined secure pit and the disposal pit covered with soil and closed. The disposal pit location to be fenced to prevent any stray animal / unauthorised man entry. Most of the hired drill rigs are provided with facility for maximum recycle of drilling fluids. The site during construction phase is provided with waste pit to hold treated/settled liquid wastes. The cuttings are segregated and stored in confined area and used later on being inorganic in nature for reclaiming the site or for preparation of approach road. Waste pits are provided with adequate holding capacity to store the wastewater generated during entire drilling phase of the rig. The waste pits are lined with impervious material to prevent leachate and percolation into groundwater Management of the Solid Wastes Small amounts of solid wastes will be generated during normal operation at the drilling rig. Measures for effective waste management include: Solid wastes generated on the Drilling Rig will be properly segregated; The wastes will be disposed on compliance with local and national legislations; Spent waste oil to be stored in a secure paved area and disposed to MoEF/ MPCB approved waste oil recyclers; Ensure that a waste management programme is implemented to minimize the amounts generated. ONGC has a well established waste management plan which is strictly implemented at all well sites; Ensure all waste packaging material are suitably stored and kept to prevent unintended use; Drill cuttings and sludge from drilling mud to be buried within the impervious lined pit and covered with soil as part of the site abandonment plan; Biodegradable waste arising from kitchen and canteen activities to be scientifically composted and the bio-manure so generated to be used for green belt development. Alternatively, the food wastes to be disposed as domesticated animal feed; VIMTA Labs Limited, Hyderabad C4-28

132 Chapter-4 Impact Assessment and Mitigation Measures Proper training and information on regulatory requirements shall be provided to the staff responsible for waste disposal to ensure proper disposal of the waste; and Inventory of solid waste generation and type shall be prepared and disposal facilities should be audited for suitability prior to the commissioning of drilling programme. The drill cuttings are washed on the screen and separated. Quantity of cutting vary from well to well depending on well drill programme, casing policy and depth of well. About m 3 /well of drill cuttings - are envisaged per well. These cuttings are inorganic in nature and stored at the corner of a drill site and later removed from the site when site is reclaimed Management of Discharge of Aqueous Effluents Wastewater generated from drilling rig wash down possibly contains mud, lubricants and residual chemicals in traces resulting from small leaks or spills. Though, these are all relatively low volume discharges containing small residual quantities, measures shall be taken to ensure no waste is discharged directly onto the land or in a manner to impact any water body. Potential control measures include: The drilling rig should be equipped with suitable containment and treatment systems as part of the contract specifications; ONGC shall also ensure that good housekeeping standards are maintained to prevent hydrocarbons and other containments entering the storm water drainage systems; Careful consideration should be given and necessary controls exercised to minimize the amount of waste generated; The spent drilling fluid to be stored in impervious lined pit with sufficient free board to prevent any overflows. On completion of the drilling operation the waste drilling fluid to be solar evaporated; and The sanitary effluents should be treated in a septic tank system designed for the anticipated person equivalent loading and the treated sewage to be let out into soak away pits Soil Erosion The following mitigative measures shall be taken to reduce the impact of soil erosion: Minimize area extent of site clearance, by staying within the defined boundaries; Stockpile of topsoil wherever possible and applicable at the edge of site; VIMTA Labs Limited, Hyderabad C4-29

133 Chapter-4 Impact Assessment and Mitigation Measures Install and maintain effective run-off controls, including siltation ponds, traps and diffusion methods so as to minimize erosion; and Avoid uprooting trees or removing undergrowth where possible so as to retain land stability; Management of waste disposal sites within Drill site ONGC will dispose the drill cuttings, drill mud and waste water generated during the drilling operations into the lined pits of various sizes and undertaking plantation within the drill site particularly on the reclaimed pits Drilling Program Safety Guidelines All API, Indian Petroleum Act and Indian Mines Act shall be strictly adhered to. Drilling Contractor s safety guidelines shall be strictly adhered to along with all Personnel Safety Guidelines. The well site supervisor shall carry out regular safety checks. All crew members would be reminded frequently of working safety aspects as part of work procedure. Should unsafe equipment or procedures be observed, operations would cease immediately and the hazard duly corrected. The well site supervisor would ensure that the Driller and above should have a valid Well Control Certification. Driller and above would have sound knowledge of the API specification relevant to Well Control Practices (API RP53 and those prescribed in it) and practice the same in all aspects of the job. The well site supervisor would maintain a separate mud material inventory and would ensure that accurate amounts of material used are entered in the Contractor s daily drilling reports. Contractor would ensure that a document is posted in the doghouse showing maximum back pressure held on casing" vs. various mud densities and would supply daily and weekly rig inspections by the company representative and the tool pusher. A detailed inspection would be carried out prior to drilling out the surface casing it would be ensured that all inspections are recorded in the tour book. 4.4 Monitoring Environmental Performance Environmental performance should be monitored throughout the drilling programme. ONGC should develop specific environmental inspection / monitoring plans and environmental audits. The environmental inspection / monitoring program shall include all the phases of the proposed activity (namely pre-drilling, drilling, testing and post drilling project activity). The wastewater from the drilling mud collection and recirculation pond should be tested. The detailed monitoring plans / inspection and environmental audit should become a part of the operating procedures for the work programme. 4.5 Emergency Response and Contingency Planning VIMTA Labs Limited, Hyderabad C4-30

134 Chapter-4 Impact Assessment and Mitigation Measures An emergency response plan will be in place for the drilling operations. These plans will define the responsibilities and resources available to respond to the different types of emergency envisaged. Training exercises will be held to ensure that all personnel are familiar with their responsibilities and that communication links are functioning effectively. The Disaster Management Plan (DMP) details the emergency response and preparedness plan to be implemented. VIMTA Labs Limited, Hyderabad C4-31

135 wells in Existing NELP Block AA-ONN- 2001/2, Kolasib & Mamit District, Mizoram Chapter-4 Impact Assessment and Mitigation Measures TABLE-4.11 SUMMARY OF ENVIRONMENTAL MANAGEMENT ACTIONS Potential Impact Action Responsibility Parameters for Monitoring Timing 1. Land take 1.1 Ensure that all necessary protocols ONGC, Land Acquisition Check list of action items Pre-deployment of are followed and legal coordinators topographic survey team requirements implemented: or site clearance crew. a) Ensure that appropriate legal requirements have been met with Land Acquisition regard to land occupancy, land coordinators ownership or usage rights, notice and compensation etc; b) Establish and clearly document land take agreements with owners, users and state authorities. 1.2 Mark out site boundaries. Ensure that land take during drilling site construction is restricted to pre-agreed area 2. Soil Erosion 2.1 Minimize area extent of site clearance, by staying within defined boundaries. 2.2 Stockpile of topsoil wherever possible and applicable at the edge of site. 2.3 Install and maintain effective runoff controls, including siltation ponds, traps and diffusion methods so as to minimize erosion. 2.4 Avoid uprooting trees or removing undergrowth where possible, so as to retain land stability. ONGC/Contractors Site boundaries marked After selection of precise site location and orientation. Prior to onset of site clearance. Contractor Supervisor Site boundaries marked Prior to onset of site clearance. Contractor supervisor Drilling Site manager Topsoil stockpile in place on site edge. Condition of siltation ponds. Rill or gully development in immediate off-site surroundings. Site Construction. Duration of program up until demobilization. Site construction. Duration of program and beyond. Contractor supervisor Trees to be preserved identified Site clearance. 3. Habitat disturbance 3.1 Mark out site boundaries Drilling Site manager Clear boundary markers in place. Prior to commencement of site clearance. 3.2 Avoid uprooting trees and other Contractor Supervisor Trees to be preserved identified Entire drilling campaign plants where possible so as to VIMTA Labs Limited, Hyderabad C4-32

136 wells in Existing NELP Block AA-ONN- 2001/2, Kolasib & Mamit District, Mizoram Chapter-4 Impact Assessment and Mitigation Measures Potential Impact Action Responsibility Parameters for Monitoring Timing facilitate subsequent re-growth. 3.3 For cleared areas, retain top soil in stockpile where possible on perimeter of site for subsequent re-spreading onsite during restoration Contractor Supervisor Topsoil stockpile in place on site edge. Duration of programme until Demobilization or prior opportunity for revegetation of verges. 4. Fuels, Lubricants and Chemicals Management 5. Waste and Effluent Management 3.4 All bulldozer operators involved in site preparation shall be trained to observe the defined site boundaries. 3.5 Hunting, fishing and wildlife trapping is forbidden. Removal or disturbance to nesting or breeding birds and animals, their eggs or young is strictly prohibited. 4.1 Maintain strict inventory of all fuel, lubricants and chemicals brought to the drilling site. 4.2 All fuels, lubricants and chemicals placed in controlled storage. 4.3 All used and unused lubricants and chemicals no longer required, to be stored in a secure paved area and disposed to authorized recyclers 4.4 Refueling operations to be undertaken over area with impervious flooring and surface drainage with oil traps. 4.5 Delivery of fuel to drilling site to be supervised. 4.7 Adequate oil spill containment and clean-up equipment and materials on-hand and available to contain foreseeable oil spill. 5.1 Implement Drilling Waste Management Plan Contractor Supervisor Maintenance of integrity of boundary markers. Duration of site preparation. Contractor Supervisor Awareness training Entire drilling campaign Drilling Site manager Up-to-date inventory in place. -do- Contractor Supervisor Periodic checking of Integrity of storage area, impervious liner; All drums and containers located within footprint of storage area. Drilling Site Manager Validity of authorization of the approved recyclers; Manifest and records to be maintained; Drilling Site Manager. Paved facilities to be installed and training to concerned to be provided. Drilling Site Manager. Construction Supervisor/ Drilling Site manager Drilling site Manager. Detailed procedure in place and training to concerned provided. Facilities and inventories readily available and in good working order. Comprehensive Waste Management Plan in place and available at site. -do- -do- -do- -do- Entire drilling campaign Prior to site clearance. VIMTA Labs Limited, Hyderabad C4-33

137 wells in Existing NELP Block AA-ONN- 2001/2, Kolasib & Mamit District, Mizoram Chapter-4 Impact Assessment and Mitigation Measures Potential Impact Action Responsibility Parameters for Monitoring Timing 6. Soil Contamination 6.1 Impervious liners in place for Contractor Supervisor Evidence of protective measures in place. No visual sign of oil spills. a. Fuel, lubricants and chemicals storage area. Daily throughout duration of programme. b) cuttings pit; $ streamside pump set station. 6.2 Effective bunds capable of containing 110% of the volume of the largest container within and enclosing all potentially contaminating materials. To be used for fuel lubricants and chemicals storage area. 6.3 Non - contaminated and potentially contaminated run-off will be kept separate. Non-contaminated run-off will be routed to off-site areas via silt traps. Potentially contaminated surface run-off will be routed through oil traps 6.4 Oil drip pans shall be used wherever there is significant potential for leakage including, but not limited to; drill rig engine; electric generator engine; compressors, pumps or other motors; maintenance areas; fuel transfer areas. 6.4 All spills/leaks contained, reported and cleaned up immediately: oil absorbent /spill containment material deployed to contain large spills; contaminated soil dug up, placed in drums and subsequently removed from site. Contractor Supervisor Drilling Site manager Contractor Supervisor Contractor Supervisor Evidence of protective measures in place. Absence of visual evidence of contamination. Evidence of separate routes and effectively working silt traps. Oily water separation in good working order. Drip pans in place. Absence of visible signs of soil contamination. Written spill procedure in place. Oil spills containment materials onsite (and always ready for deployment). Spill reporting procedure in place Daily throughout duration of programme. Duration of entire drill programme. Duration of entire drill programme. Duration of entire drill programme. VIMTA Labs Limited, Hyderabad C4-34

138 wells in Existing NELP Block AA-ONN- 2001/2, Kolasib & Mamit District, Mizoram Chapter-4 Impact Assessment and Mitigation Measures Potential Impact Action Responsibility Parameters for Monitoring Timing 7. Water quality and other aquatic impacts. 7.1 No untreated discharge to be made to watercourses. 7.2 Minimize suspended solids loads to watercourses by installing appropriate surface run-off drainage systems (eg silt traps) Drilling Site manager Ensure no untreated effluent discharged on land or watercourse from the drilling site / campsite. Contractor Supervisor Surface drainage systems in good working order. Absence of visible erosion and gullies. Absence of visible suspended solids loads in streams. Duration of programme with particular emphasis during site layout design and site construction. Duration of programme. 8. Noise and Vibration (Applies to Site preparation as well as drilling) 8.1 List of all potential noise / vibration generating machinery on-site identifying age of plant. Drilling Site manager Results from water monitoring programme. Ensure that the drilling rig DG sets have acoustic hoods and noise dampers in place; Mapping of noise generating equipments noise levels before commencement of drilling and once during the drilling operation; Prior to commencement of work by contractors at each drilling site. During drilling operation 8.2 Equipment maintained in good working order. Workers near noise source provided with noise protection equipment (ear muffs) Contractor Supervisor Check the anti-vibration pads / other measures in place to attenuate transmission of machinery vibration Written record of maintenance for all equipment. Prior to commencement of work by contractors at each drilling site. Monitor effective use of personnel protective equipments 8.3 Implement good working practices Contractor Supervisor No machinery running when not Duration of entire drill to minimize noise. required. programme. 8.4 Acoustic mufflers in large engines Contractor Supervisor Mufflers in place. Duration of entire drill (where practicable) programme. 9. Air Emissions 9.1 All equipment operated within Drilling Site manager N/A Duration of entire drill VIMTA Labs Limited, Hyderabad C4-35

139 wells in Existing NELP Block AA-ONN- 2001/2, Kolasib & Mamit District, Mizoram Chapter-4 Impact Assessment and Mitigation Measures Potential Impact Action Responsibility Parameters for Monitoring Timing specified design parameters (site preparation and drilling phases) programme. 9.2 Any dry, dusty materials Contractor Supervisor Absence of stockpiles or open Duration of entire drill (chemicals, mud etc) shall be containers of dusty material. programme. stored in original packings and loose storage avoided (wherever possible). 10 Socio-Economic impacts 9.3 Well testing (flaring) to be undertaken so as to minimize impacts of emissions: Duration of testing minimized by careful planning; High combustion efficiency, smokeless flare/burner to be used Well site to be developed to avoid any habitat and cultural / archaeological centers Drilling site Manager / Contractors supervisor ONGC Land Acquisition Supervisor Check flare controls before flaring; Physical Inspection during flaring; Maintenance checklist of flaring equipment; Check firewall in place, where required and flare direction Checklist of action items. Well testing. At the initial stage of well site planning 10.2 Adequate dialogue with the local population and the authority while designing compensation packages, close monitoring on the type of land loss: Permanent Temporary Protection of traditional water structures provision of health and education services. ONGC Land acquisition supervisor Continued dialogue with the local villagers and other stake holders Project management plan should incorporate these aspects at the initial planning stage All through drilling and post drilling operation Loss of land and crop loss to be compensated Provide temporary employment generation opportunities, where feasible During site acquisition phase During the site preparatory works VIMTA Labs Limited, Hyderabad C4-36

140 Chapter-4 Impact Assessment and Mitigation Measures 4.6 Waste Management Plan The Waste Management Plan (WMP) covers disposal of all wastes with further reference to off-site disposal of those wastes, which cannot be dealt with on-site. The objectives of the WMP are: To provide the drilling contractor with the necessary guidance for the reduction and appropriate management of wastes generated on the drilling site; To comply with all current Indian environmental regulations and ONGC requirements; To meet industry standards on waste management and control; and To prevent occurrence of any environmental degradation within the vicinity of the well site due to waste handling Classification of Waste In general, wastes generated during the drilling activities can be categorized as follows: Paper - any paper waste generated as a result of drilling activities, inclusive of uncontaminated fluid, sacks, cement and food containers, office wastes, newspapers, packaging material, etc; Wood - waste pallets used for carriage of fluid and cement or packing crates; Plastic - shrink wrapping on fluid/cement, protective material, kitchen and domestic container wastes; Inert Waste - metal cans, glass jars, various containers, etc. which are not combustible and do not contain toxic or hazardous substances and are not under pressure; Liquid Wastes - any liquid wastes, chemicals or receptacles. This also includes small volumes of paints, solvents, lubricating oil, antifreeze, etc.; Solid Wastes - fluid, cement, or testing chemicals, containers holding or previously holding volumes of chemicals; Waste Lead Acid batteries: Spent batteries from equipment and DG set operations; Contaminated Soils - Soils contaminated by chemicals and oil; Hydrocarbon Wastes - waste oils, eg from oil changes or leakage from equipment or storage tanks; Produced Hydrocarbons - gas, condensate or oil produced during well testing; Drill Cuttings - drilled formation cuttings, consisting of shale, sands and carbonate ideologies; and Drilling Fluids - fluids used in the drilling or completion of the wells. VIMTA Labs Limited, Hyderabad C4-37

141 Chapter-4 Impact Assessment and Mitigation Measures Disposal Options The following disposal options will be available on site. However, ONGC will evaluate the suitability of various waste specific technologies for the site and select an option that will cause minimum environmental impact on the surrounding: Landfill ONGC will dispose off non-hazardous inert solid waste by compacting the waste to the smallest practical volume and final disposal at the designated site of MPCB; Offsite Disposal Wastes which cannot be handled at the drilling site will be removed by ONGC to and designated authorized sites of MPCB; Produced Hydrocarbon Flaring - Hydrocarbons produced during well testing will be flared via a high efficiency burner system; Cuttings All the Drilled cuttings generated will be disposed off into lined pits within the drill sites; Sewage Treatment and Disposal - A septic tank system with soak away pits will be constructed on the drilling site / camp site. Digested sludge, will be used as manure for green belt programme under restoration plan Labelling of Waste Any wastes, which cannot be dealt with on site, will be removed to a suitable location for further handling and/or disposal. All off-site transportation and disposal of hazardous waste (as per the Hazardous Waste Rules, 2000 Schedule I & II) shall be done after obtaining necessary authorization from MPCB. Wastes will be clearly labelled according to: Non-hazardous wastes mentioning type of waste; Hazardous wastes as per Hazardous Waste Management & Handling Rules Form Drilling Site Restoration Plan Upon completion of drilling the drilling rig and crew will demobilize from the site. All equipment and debris will be removed and the site will be returned to an acceptable condition including revegetation (re-forestation) as required. Special care will be taken in sealing of the cuttings pit to ensure that there is no leaching of contaminants into the surrounding soils and that the fluid pit is buried to sufficient depth as not to interfere with existing land-use. If a commercial discovery is made, the site will be restored to a standard acceptable depending on the requirements of the local authorities and consistent with future land-use. Residual slurries in the waste and water pits will be buried in the PPE lined pits. This will constitute a secured landfill site. The residue in the pits will be covered with soil and impervious layer spread over this. One metre of topsoil cover will be placed the surface profiled to enhance the runoff of rain watered. VIMTA Labs Limited, Hyderabad C4-38

142 Chapter-5 Analysis of Alternatives 5.0 ANALYSIS OF ALTERNATIVES 5.1 Alternatives for Technology The technology to be used in the proposed project has been explained extensively in Chapter-2. The exploratory drilling facilities involved in the project are very simple technologies and very much tested and being used world-wide in Oil and Gas industry. No technology alternatives were considered as the project involves only exploratory drilling facilities. 5.2 Alternatives for Project Site Consideration of the alternate project sites is not applicable as the exploratory drilling wells in NELP Block has received Mining Lease of these areas from MOPNG, Govt of India for exploring and producing hydrocarbons. VIMTA Labs Limited, Hyderabad C5-1

143 Chapter-6 Environmental Monitoring Programme 6.0 ENVIRONMENTAL MONITORING PROGRAMME 6.1 Introduction Regular monitoring of environmental parameters is of immense importance to assess the status of environment during project operation. With the knowledge of baseline conditions, the monitoring programme will serve as an indicator for any deterioration in environmental conditions due to operation of the project, to enable taking up suitable mitigatory steps in time to safeguard the environment. Monitoring is as important as that of control of pollution since the efficiency of control measures can only be determined by monitoring. Usually, as in the case of the study, an Impact Assessment study is carried over short period of time and the data cannot bring out all variations induced by the natural or human activities. Therefore, regular monitoring programme of the environmental parameters is essential to take into account the changes in the environmental quality. 6.2 Environmental Monitoring and Reporting Procedure Development of the programmes during the planning process shall be conducted or supported by environmental specialists. However, the implementation responsibility rests with line managers, who should, therefore, ensure they fully understand and subscribe to the commitments being made. These commitments will include the legal and statutory controls imposed on the operation as well as other corporate commitment to responsible environment management. The key aims of monitoring are: first to ensure that results/conditions are as forecast during the planning stage, and where they are not, to pinpoint the cause and implement action to remedy the situation. A second objective is to verify the evaluations made during the planning process, in particular in risk and impact assessments and standard and target setting and to measure operational and process efficiency. Monitoring will also be required to meet compliance with statutory and corporate requirements. Finally, monitoring results provide the basis for auditing. A more detailed approach to monitoring and performance measurement is provided in various publications Objectives of Monitoring The objectives of monitoring are to: Verify effectiveness of planning decisions; Measure effectiveness of operational procedures; Confirm statutory and corporate compliance; and Identify unexpected changes Monitoring Schedule Periodic environmental monitoring schedules are prepared covering various phases of project advancement. This comprises the duration of proposed exploratory drilling as well as post-project phase, when the hydrocarbon is established in the VIMTA Labs Limited, Hyderabad C6-1

144 Chapter-6 Environmental Monitoring Programme wells and production program is undertaken as well as the Decommissioning/ Closure Phase for minimum 10 years. In order to assess the extent and nature of impacts on environment due to drilling operations, the monitoring on various attributes of environment will be carried out during various phases of drilling as under: Pre-Drilling Phase: Prior to the start of drilling activities, the environmental status around the proposed drilling locations shall be monitored. These results will represent the baseline environment status, against which the monitoring results from the other phases are compared. Drilling Phase: Monitoring during drilling phase serves as a measure of the impact on the environment due to drilling operations. Besides, the analysis of drill cuttings and drilling mud at various depths shall be carried out as per MoEF&CC guidelines on disposal of drilling wastes. Testing Phase: Well testing is a short term activity spread over a period of 2 to 3 days. Testing operations are carried out to determine the presence of hydrocarbons and to understand the reservoir characteristics. Monitoring during this phase will serves as a measure of the impact on the environment due to testing operations. Post-Drilling Phase: Monitoring shall be carried out after completion of drilling and testing operations to determine if there has been any residual impact on the environment due to drilling and testing operations. The detailed monitoring program covering development drilling phase is given in Table-6.1. TABLE-6.1 SCHEDULE OF ENVIRONMENTAL MONITORING Sr. No. of Aspect Parameter Frequency No. Locations I. Pre-drilling Phase 1 Ambient air quality PM10, PM2.5, SO2, NOx, CO and Hydrocarbons as CH4 Two days in week 4 locations 2 Noise monitoring Leq(n), Leq(d), Leq(dn) Once 4 locations 3 Water quality As per IS: including heavy metals Once Min 5 locations 4 Soil quality Texture, conductivity, organic carbon, P2O5, K2O, ph, Cl, O & G, Heavy metals viz. Cr, Ni, Cu, Zn, Cd, Hg and Pb Once 8 locations II. Drilling Phase Two days in 1 Ambient air quality PM10, PM2.5, SO2, NOx, CO and Hydrocarbons as CH4 week for two weeks 4 locations 2 Noise monitoring Leq (n), Leq(d), Leq(dn) Once 4 locations 3 Source emissions monitoring Flue gas temp., velocity, flow, dust conc., SO2, NOx Once 4 samples 4 Water quality ph, TDS, Alkalinity, F, Sulphates, Cl, Cr, Ni, Cu, Zn, Cd, Pb Once Min. 5 locations III. Testing Phase 1 Ambient air quality PM10, PM2.5, SO2, NOx, CO Two day in 4 locations VIMTA Labs Limited, Hyderabad C6-2

145 Chapter-6 Environmental Monitoring Programme Sr. No. Aspect Parameter Frequency No. of Locations and Hydrocarbons as CH4 week for two weeks 2 Noise monitoring Leq(n), Leq(d), Leq(dn) Once 4 locations IV. Post Drilling Phase 1 Ambient air quality PM10, PM2.5, SO2, NOx, CO and Hydrocarbons as CH4 Two days in week 4 locations 2 Water quality As per IS: including heavy metals Once Min. 5 locations 3 Soil quality Texture, conductivity, organic carbon, P2O5, K2O, ph, Cl, O & G, Heavy metals viz. Cr, Ni, Cu, Zn, Cd, Hg and Pb. Once 8 locations 6.3 Reporting Schedules of the Monitoring Data It is proposed that voluntary reporting of environmental performance with reference to the EMP should be undertaken. The environmental monitoring cell shall co-ordinate all monitoring programmes at site and data thus generated shall be regularly furnished to the State regulatory agencies. The compliance reporting shall be on six monthly basis to the local State PCB officials and to Regional Office of MoEF. The Environmental Audit reports shall be prepared for the entire year of operations and shall be regularly submitted to regulatory authorities. 6.4 Infrastructure for Monitoring of Environmental Protection Measures A well-equipped laboratory with consumable items shall be provided for monitoring of environmental parameters in the site. Alternatively, monitoring can be outsourced to a recognized reputed laboratory. The following equipment and consumable items shall be made available in the site for environmental monitoring. Air Quality and Meteorology High volume samplers, Stack monitoring kit, Personal Dust sampler, Central Weather Monitoring Station, Spectrophotometer (visible range), Single pan balance, Flame photometer, Relevant Chemicals as per IS:5182. Water and Wastewater Quality The sampling shall be done as per the standard procedures laid down by IS: The equipments and consumables required are: BOD incubator, COD reflex set-up, Refrigerator, Oven, Stop watch, Thermometer, ph meter, Distilled water plant, Pipette box, Titration set, Dissolved oxygen analyser, Relevant chemicals. VIMTA Labs Limited, Hyderabad C6-3

146 Chapter-6 Environmental Monitoring Programme Noise Levels Noise monitoring shall be done utilising an integrating sound level meter to record noise levels in different scales like A-weighting with slow and fast response options. 6.5 Environmental Costs All costs involved in environmental mitigating measures and management are included in the project cost. 6.6 Audit and Review Review and audit is essentially a management tool. However, its application is crucial at the operational level for verification and feedback on the effectiveness of organization system and environmental performance. Basically, Auditing involves in the following items: Line management system; Awareness and training; Procedures, standards, targets; Plans: waste, contingency, pollution control compliance; Monitoring programmes; Verify Environmental Impact Assessment; Verify mitigation; Reporting and communication; Documentation; and Feedback. Audit serves to substantiate and verify monitoring programmes and compliance, and to ensure that site environmental plans, procedures and standards are both effective and fit for purpose. Other benefits of auditing include increased internal and external awareness, communication and credibility of company environmental activities by demonstrating commitment to and achievement of responsible environmental management. In addition to management and compliance audits, a number of technical or process audits, sometimes termed assessments or valuations, may be conducted. Thus, waste and emissions audits, energy audits, site (contamination) audits, emergency counter measure audits, worker health and safety audits, may be instigated independently or as part of a broader management audit. Reports on environmental performance shall be made available for a wide public readership including shareholders and financing bodies. An important audience is also the company employees, who benefit from having the company's environmental position and activities described in a way that allows him or her to be an ambassador in a general sense for the company. Reporting is becoming increasingly sophisticated, and more closely linked with the total environmental programme of companies. The contents of these reports still vary greatly, with a gradual but noticeable tendency to quantify environmental performance, and include mention of a range of environmental and sustainability indicators such as pollution and safety incidents, greenhouse gas emissions, and even non-compliance statistics. VIMTA Labs Limited, Hyderabad C6-4

147 Chapter-7 Additional Studies 7.0 ADDITIONAL STUDIES This chapter describes the Risk Assessment and Disaster Management Plan, occupational health and safety issues. 7.1 Risk Assessment Environmental Risk Assessment is a scientific analysis for identification of credible risk and thereafter estimating the safe distances from any hazardous installations/processes in the eventuality of an accident. Estimation of nearaccurate safe distances is absolutely necessary to protect the public, property and environment. Risk Assessment also known as Hazard Analysis and Vulnerability Assessment is a procedure for identifying hazards and determining their possible effects on a community and environment. Risk or hazard by itself is not an event - it is the potential for an event Approach to the Study Risk involves the occurrence or potential occurrence of various type accidents consisting of an event or sequence of events. The main objectives of the risk assessment of the proposed onshore exploratory drilling are illustrated schematically in Figure-7.1. Standard industry practices of risk assessment are considered in the project. Maximum Credible Accident analysis is carried out to arrive at the hazard distance for the worst case scenario Maximum Credible Accident Analysis (MCAA) Maximum Credible Accident (MCA) is a probable accident with maximum damage distance. In practice, the selection of accident scenarios for MCAA is carried out on the basis of engineering judgement and past accident analysis. MCAA does not include quantification of the probability of occurrence of an accident. Risk involves the potential occurrence of some accident consisting of an event or sequence of events. Accidental release of oil and gas to the atmosphere from well or processing equipment is studied by visualising scenarios on the basis of their properties and the impacts are computed in terms of damage distances. A disastrous situation is the outcome of fire or explosion of the released gas in addition to other natural causes, which eventually leads to loss of life, damage to property and/or ecological imbalance. Depending on the effective hazardous attributes and their impacts, the maximum effect to the surroundings could be assessed. The steps of MCA analysis along with data requirement are shown in Figure-7.2. VIMTA Labs Limited, Hyderabad C7-1

148 Chapter-7 Additional Studies Past Accident Data Analysis The data required for MCA analysis has either to be generated by monitoring and/or collected from the records of the past occurrences. This data, when analysed, helps in formulation of the steps towards mitigation of hazards faced commonly. Trends in safety of various activities can be evaluated and actions can be planned accordingly, to improve the safety. Data analysis helps in correlating the causal factors and the corrective steps to be taken for controlling the accidents. It is, therefore, of vital importance to collect the data methodically, based on potential incidents, sections involved, causes of failure and the preventive measures taken. This helps to face future eventualities with more preparedness. Hazard Identification A major hazard is defined as an event, which may have the potential to cause one or more fatalities and also the potential to affect the integrity of the facility as a whole. The aim of this step is to create a complete tabulation of identified hazards. Hazards are identified in terms of safety and/or environmental impact. The hazard in terms of blowout has been identified from well pad in the present exploratory drilling project. It is noted that some hazards are incorporated within other hazards. Identification of hazards in the proposed drilling campaign is of primary significance in the analysis, quantification and cost effective control of accidents involving chemicals and process. Hence, all the components of a system /process need to be thoroughly examined to assess their potential for initiating or propagating an unplanned event/sequence of events, which can be termed as an accident. Typical schemes of predictive hazard evaluation and quantitative risk analysis suggest that hazard identification step plays a key role. The hazard in terms of blowout has been identified from well pad in the present exploratory drilling project. Major accident hazards considered are: Hydrocarbon escapes due to high geological pressures lead to possibility of fire, explosion, gas ingress to sensitive areas, contamination or toxic hazards arising from wells, test equipment fuel supply systems, storage, pipe work systems, etc.; Structural or foundation failure, including effects of corrosion, fatigue, extreme weather, overloading, seismic effects, abuse or accidental loading; Possibility of H2S release while drilling; and Fire, including fires in accommodation, electrical fires, hot work, oxygen enrichment VIMTA Labs Limited, Hyderabad C7-2

149 Chapter-7 Additional Studies The complete list of hazards and Occupational Hazards applicable to onshore drilling are presented in Table-7.1 and Table-7.2. TABLE-7.1 LIST OF MAJOR HAZARDS Sr. Hazard Description Impacts No. Source/Reason 1 Fire and Explosion Occurrence of Blow Out Topsides blow out Non hydrocarbon fires Electrical fire in control room Fire in accommodation 2 Impacts and Collisions Objects dropped from a crane/ derrick Fatal accidents Loss of materials and equipment 3 Loss of station/ stability Loss of stability Structural failure Tug failure (during towing) 4 Extreme Weather Loss of lives and material Conditions Extreme winds Temporary withdrawal of well operations 5 Earthquakes Sudden ground movement Strong vibrations, failure 6 War, Crisis Crisis situation - TABLE-7.2 OCCUPATIONAL HAZARDS Sr. No. Hazard Description Specific Hazard 1 Working at heights Fall Fall Man overboard 2 Disease/ Illness Illness Medical evacuation 3 Storage of chemicals Release of Exposure to chemicals, inhalation, chemicals ingestion, body contact etc Consequence Analysis Quantification of the damage can be done by means of various models, which can then be translated in terms of injuries and damage to the exposed population and buildings. Oil and gas may be released and result into jet fire & less likely unconfined vapour cloud explosion causing possible damage to the surrounding areas. Extent of the damage depends upon the nature of release. The release of flammable material and subsequent ignition results in heat radiation, pressure wave or vapour cloud depending upon the flammability and its physical state. VIMTA Labs Limited, Hyderabad C7-3

150 Chapter-7 Additional Studies Hazard Identification Identification of potential hazard zones Scenario Identification Assessment of Risk (via MCA Analysis) Identification of representative failure cases Failure Frequency Analysis Consequent Analysis Risk Mitigation Measures Disaster Management Plan o Emergency Classification o Roles & Responsibilities FIGURE-7.1 OBJECTIVES OF RISK ASSESSMENT VIMTA Labs Limited, Hyderabad C7-4

151 Chapter-7 Additional Studies MAXIMUM CREDIBLE ACCIDENT (MCA) ANALYSIS Probable accident with maximum damage distance DATA REQUIREMENT Steps in MCA Analysis Operation Procedures Detailed design parameters Physical & chemical properties data Detailed information about facility Past accident data Past Accident Data Analysis Past accident database generation Analysis of created database Hazard Identification Hazard identification in terms of safety and environmental impact Identification of representative failure cases for the wells and various equipments Consequence Analysis Damage distance computations for the released cases Identification of release scenario Calculation of damage distances for various Heat Loads Emergency Planning FIGURE-7.2 METHODOLOGY OF MCA ANALYSIS VIMTA Labs Limited, Hyderabad C7-5

152 Chapter-7 Additional Studies An insight into physical effects resulting from the release of hazardous substances can be had by means of various models. The results of consequence analysis are useful for getting information about all known and unknown effects that are of importance when some failure scenario occurs and also to get information as how to deal with the possible catastrophic events Damage Effects of Various Heat Loads Damage effects of various peak over pressures and incident radiation intensities are detailed in Table-7.3 and Table-7.4 respectively. TABLE-7.3 DAMAGE DUE TO PEAK OVER PRESSURE Human Injury Structural Damage Peak Over Type of Damage Peak Over Type of Damage Pressure - bar Pressure- bar % lethality 0.3 Heavy (90% damage) % lethality 0.1 Repairable (10% damage) 2-3 Threshold lethality 0.03 Damage of Glass Severe lung damage 0.01 Crack of Windows 1-1 1/3 50% Eardrum rupture - - Source: Marshall, V.C. (1977) 'How lethal are explosives and toxic escapes' Sr. No. TABLE-7.4 DAMAGE DUE TO INCIDENT RADIATION INTENSITIES Incident Radiation (kw/m 2 ) Type of Damage Intensity Damage to Equipment Damage to People Damage to process equipment 100% lethality in 1 min. 1% lethality in 10 sec Minimum energy required to ignite wood 50% Lethality in 1 min. at indefinitely long exposure without a Significant injury in 10 sec. flame Maximum thermal radiation intensity allowed on thermally unprotected -- adjoining equipment Minimum energy to ignite with a flame; 1% lethality in 1 min. melts plastic tubing Causes pain if duration is longer -- than 20 sec, however blistering is un-likely (First degree burns) Causes no discomfort on long -- exposures Source: Techniques for Assessing Industrial Hazards by World Bank Scenario Identification Emergency scenario is identified based on past experiences and historical evidences. A flowchart that can be followed to evaluate the consequences of the release of a flammable or toxic chemical is given in Figure-7.3. Historical evidence demonstrates that although unlikely, the most significant hazard arises from the thermal radiation produced by an ignited liquid or gas release. Releases from the wells could arise in the form of blowouts. This may lead to release of gas into the atmosphere. An availability of ignition source can lead to jet fire. VIMTA Labs Limited, Hyderabad C7-6

153 Chapter-7 Additional Studies Model for the Calculation of Heat Loads and Shock Waves If a flammable gas or liquid is released, damage resulting from heat radiation or explosion may occur on ignition. Humidity of the air (water vapour) has a relatively high heat-absorbing capacity. The orientation (horizontal / vertical) of the object irradiated with respect to the fire is an important factor to be considered. If a jetted release of the oil & gas mixture is ignited, a stable diffusion torch or jet fire may be produced. For the flammable gas, in this model, an ellipse is assumed for the shape of a torch. The volume of the (torch) flare in this model is related to the outflow. In order to calculate the thermal load, the centre of the flare is regarded as a point source. This centre is taken as being half a flarelength from the point of outflow. A flash fire is the non-explosive combustion of vapour cloud resulting from release of a flammable material in the atmosphere, which after mixing with air, ignites. A flash fire results from the ignition of a released flammable cloud, in which there is essentially no increase in combustion rate. The ignition source could be electric spark, a hot surface, and friction between moving parts of a machine or an open fire. Part of the reason for flash fire is that flammable fuels have a vapour temperature less than ambient temperature. Hence as a result of spill, they are dispersed initially by the negative buoyancy of the cold vapours and subsequently by atmospheric turbulence. After the release and dispersion of a flammable fuel, the resulting vapour cloud is ignited and when the fuel vapour is not mixed with sufficient air prior to ignition, it results in the diffusion fire burning. Therefore, the rate at which the fuel vapour and air are mixed together during combustion determines the rate of burning in the flash fire. The main dangers of flash fires are radiation and direct flame contact. The size of the flammable cloud determines the area of possible direct flame contact effects. Radiation effects on a target depend on several factors including its distance from the flames, flame height, flame emissive power, local atmospheric transitivity and cloud size. Most of the time, flash combustion of a flash lasts for no more than a few seconds Input Data for Consequence Analysis The data used for the consequence analysis is depicted in Table-7.5. TABLE-7.5 INPUT DATA FOR CONSEQUENCE ANALYSIS Parameter Case Ambient Temperature 35 0 C Atmospheric stability A & D Relative humidity 70% Wind speed 2 m/s for stability class A 5 m/s for stability class D VIMTA Labs Limited, Hyderabad C7-7

154 Chapter-7 Additional Studies Release of Chemical Instantaneous Continuous Bottom Top Two Phase Outflow Liquid Ignition No Pool Formation Vapours Yes Ignition? Yes Pool Fire Ignition? Yes Flare No No BLEVE Evaporation Dispersion Vapour Cloud Formation Toxicity No Ignition? Yes Vapour Cloud Explosion Flash Fire Pressure Wave Heat Radiation TOXICITY COMPUTATION CONSEQUENCE MODELLING FIGURE-7.3 FLOWCHART FOR EVALUATION OF CONSEQUENCES OF RELEASE OF FLAMMABLE OR TOXIC CHEMICAL VIMTA Labs Limited, Hyderabad C7-8

155 Chapter-7 Additional Studies Results and Discussions Jet Fire from Well (Oil) Blowout is visualised for carrying out the consequence analysis. A well blow out can lead to uncontrolled release of oil into the atmosphere. A subsequent jet fire could result on availability of an immediate ignition source. Heat load generated by the flame depends upon the mass flow rate of the released material. Damage distances are computed for the operating pressure of 290 psi and temperature of 70 C. Weather conditions 2A and 5D are considered while computing the damage distances. The damage distance of 95.7m is obtained for the heat load of 4 kw/m 2 in case of well blow out for 5D conditions. Results are shown in Table-7.6. The calculations of Pool Fire is given in Annexure-IX. TABLE-7.6 SUMMARY OF CONSEQUENCE ANALYSIS FOR JET FIRE SCENARIO AT WELL Pressure (psi) / Temp ( C) Scenario Mass Flow Rate (kg/s) Weather Damage Distance (m) for various Heat loads 4.0 kw/m kw/m kw/m / 70 Blow out 16 2A D Failure Frequency Analysis A blowout is defined as an uncontrolled release of fluid, viz., hydrocarbon (oil and/or gas), but drilling mud, completion fluid or water from a well. It is most hazardous when the fluid is hydrocarbon. Blowouts are important because they have the potential to release large amounts of hydrocarbons and are very difficult to control. A well control incident is one in which a high potential release which may result in blowouts either does not occur or is quickly stopped. They typically involve formation fluid accidentally entering the wellbore, but controlled by the available barriers such as the blowout preventer (BOP). These incidents usually have relatively minor consequences, and are not well reported. For some events, it is unclear whether they should be counted as a full blowout or as a well control incident. Different databases categorise events in different ways, and some analyses use the term "blowout" to refer to all well control incidents Historical Data Sources The main compilations of secondary data on blowouts are: SINTEF blowout database - An internal SINTEF compilation sponsored by 6 operators and 2 consultants (Holand 1995), including 319 blowouts for the period , of which 128 occurred in the US GoM OCS or North Sea during It is an update of the Marintek blowout database, for which the full list (SINTEF 1983) and an analysis (NSFI 1985) were published. Detailed analyses have been published for the period (Holand 1996, 1997). Scandpower (1995) analysed the data for the period , and included a full list of the events. VIMTA Labs Limited, Hyderabad C7-9

156 Chapter-7 Additional Studies E&P Forum database - Frequencies from BLOWOUT for the period were published by OCB / Technica (1988) and E&P Forum (1992). The secondary data on Failure Rate Frequency is given in Annexure-X Probability of Immediate Ignition and Individual Risk Assessment Criteria The information available on probability of ignition is mostly in the form of expert estimates. The details of immediate ignition probabilities used in this analysis are given in Table-7.7. This data has been obtained from E&P Forum. Similarly, the ADNOC individual risk assessment criteria are given in Table-7.8. TABLE-7.7 PROBABILITY OF IGNITION FOR LEAKS OF FLAMMABLE FLUIDS Leak Rate Probability of Ignition Gas Liquid Minor (< 1kg/s) Major (1 to 50 kg/s) Massive (>50 kg/s) Source: E&P Forum TABLE-7.8 THE ADNOC INDIVIDUAL RISK ASSESSMENT CRITERIA ADNOC Acceptability Criteria Maximum Individual Risk Criteria for Workers Maximum Individual Risk Criteria for Existing New Installation Public Installation Benchmark IR < 2 x 10-4 IR < 2 x 10-5 IR < 1 x 10-5 Unacceptable IR > 1 x 10-3 IR > 1 x 10-3 IR > 1 x 10-4 Acceptable IR < 1 x 10-5 IR < 1 x 10-5 IR < 1 x 10-6 Source: E&P Forum Individual Risk Assessment The Individual risk due to well blowout is calculated with the help of SAFETI Software. 20 persons were considered as a population present within the well pad in a shift and frequency of well blowout is taken from Annexure-X. The individual risk due to well blowout varies from 1E -06 to 1E -09 and it is concluded that the risk due to well blowout is acceptable for workers as well as for the public as per Table Geo-hazards Geo-hazards include land slides, flooding, land subsidence and earth quakes. The major geo-hazard associated with oil production is land subsidence. Land subsidence is termed as the sudden sinking or gradual downward settling of land with little or no horizontal motion, caused by a loss of subsurface support which may result from a number of natural and human caused occurrences including subsurface mining or the pumping of oil or ground water. Land subsidence events, depending on where they occur, can pose significant risks to health and safety or interruption to transportation and other services. Land subsidence is effected by characteristic of the reservoir rocks, pressure of overburden, relationship between compaction and pressure gradient in the reservoir, pressure decline dynamic and its influence on the compaction rate and the surface subsidence. VIMTA Labs Limited, Hyderabad C7-10

157 Chapter-7 Additional Studies Drilling activities do not involve any extraction of hydrocarbon and thus in this case, any possibility of subsidence is ruled out. In the event of a successful discovery leading to production activities, geo-technical investigations, geological impacts assessment will be carried out and appropriate measures will be undertaken. 7.2 Recommendations to Mitigate Risk/Hazards The recommendations to mitigate risk at the well site during the drilling operation are given in Table-7.9. TABLE-7.9 RECOMMENDATIONS TO MITIGATE BLOW OUT RISK/HAZARDS Sr. No. Mitigative Measures Remarks 1 Maintenance of mud weight Drilling Mud Engineer should check the ingoing & outcoming mud weight at the drilling well, at regular intervals; If mud weight is found to be less, barytes should be added to the circulating mud, to raise it to the desired level; Failure to detect this decrease in level may lead to well kick & furthermore, a well blow out. 2 Monitoring of active mud tank level 3 Monitoring of Hole Fill-up / return mud volume during tripping Increase in active tank level indicates partial or total loss of fluid to the well bore, which can lead to well kick; If any increase or decrease in tank level is detected, shift personnel should immediately inform the Shift Drilling Engineer & take necessary actions as directed by him. During swabbing or pulling out of string from the well bore, the hole is filled with mud for metallic displacement which returns back to the pit when the string runs back; Both the hole fill up & return mud volumes should be monitored, as they indicate any mud loss or inflow from well bore, which may lead to well kick. 4 Monitoring of inflow The flow nipple during tripping or connection time should be monitored for any inflow from the well bore 5 Monitoring of Background / trip gas Increase in background gas or trip gas indicates insufficient mud weight against drilled formation. Such indications should be immediately brought to the notice of the Shift Drilling Engineer. 6 Team Coordination Each team member must religiously follow the safety aspects pertaining to respective operational area. Drilling operation is a team effort and success of such an operation depends upon the sincerity, efficiency & motivation of all team members. Safety in such operations is not the duty of a single person, but it is everyone's job. The use of protective fireproof clothing and escape respirators will reduce the risk of being seriously burnt. Adequate fire fighting facilities and first aid facilities should be provided, in case of any emergency. Risk reducing measures include kick simulation training for personnel, presence of well trained drillers and mud engineers, and strict adherence to safety management procedures and good well control procedures. VIMTA Labs Limited, Hyderabad C7-11

158 Chapter-7 Additional Studies 7.3 Disaster Management Plan A generally accepted definition endorsed by ONGC is a critical condition that may endanger life, the environment, or Company assets. This Emergency Management Plan (DMP) addresses two levels of Emergencies: Minor (Tier I); and Major (Tier II & III). Minor Emergency An Emergency requiring local support that can be handled by members of Incident Response Team (IRT) such as: Light bodily injury requiring the assistance of the doctor or a local nurse; and Minor environmental or property damage. Major Emergency An Emergency that may require the assistance and support of the Emergency Response Group (ERG) at Regional Office in case of Tire-II emergencies and Crises Response Team (CRT) at Head Office for the Tire-III emergencies and external agencies. e.g.: Serious incidents of spills, blow outs, release of hazardous / toxic substances, structural failure / collapse; Medical evacuation in the event of life threatening bodily injury or severe electric shock, life threatening illness; Major environmental or property damage; Man lost situation; Major fire, explosion, radiation; and Unplanned evacuations such as natural calamity, war crisis, security breach Overall Philosophy of Emergency Response Initial response to any incident will be managed at the incident location; in this case, it would be the site of infill well drilling. The overall level of response will depend on the nature and scale of the emergency. The overall philosophy of emergency response is to: Ensure safety of people, protect the environment and safeguard commercial considerations; Immediate response to emergency scene with effective communication network and organized procedures; Obtain early warning of emergency conditions so as to prevent impact on personnel, assets and environment; Safeguard personnel to prevent injuries or loss of life by protecting personnel from the hazard; and Evacuating personnel from an installation when necessary and minimize the impact of the event on the installation and the environment by: Minimizing the hazard as far as possible; VIMTA Labs Limited, Hyderabad C7-12

159 Chapter-7 Additional Studies Minimizing the potential for escalation; and Containing any release Auditing Audits should be carried out on a regular basis to verify and update the Emergency Response Plan and the corresponding procedures. The audit will review: The roles and responsibilities of the ERG and support organization; The requirements of legislation and regulatory bodies; and Resource requirements and availability Emergency Priorities In the event of an Emergency occurring, the ONGC Policy lists, in order, the following priorities: Safeguard Life; Protect the Environment; Protect the Company / Third Party assets; Maintain the Company image and reputation; and Resume normal operations as soon as possible Emergency Response Management Group Interfaces The relationship between the Remote Location Incident Response Team (IRT), Emergency Response Group (ERG), Crisis Response Team (CRT) and classification of emergencies is illustrated in the Figure-7.4. VIMTA Labs Limited, Hyderabad C7-13

160 Chapter-7 Additional Studies INCIDENT REMOTE LOCATION INCIDENT RESPONSE TEAM RESPONSIBLE FOR: - DEALING WITH ALL LOCATION INCIDENTS AND EMERGENCIES - NOTIFYING & LIASING WITH COUNTRY EMERGENCY RESPONSE GROUP DUTY MANAGER TIER I INCIDENT A MINOR INCIDENT WHERE LOCATION REQUIRES NO EXTERNAL ASSISTANCE & CAN CONTROL THE INCIDENT WITH LOCATION RESOURCES. LOCATION MANAGER (E.G. IM/OIM) MUST NOTIFY EMERGENCY RESPONSE GROUP DUTY LEADER. TYPICAL INCIDENT TYPES: - MINOR OIL SPILLS SHOULD BE UPTO TEIR TONNES - MINOR MEDICAL OR INJURY CASE - EQUIPMENT DAMAGE WITHOUT LOSS OF PRODUCT - MINOR FIRE WITHOUT INJURY OR PLANT DAMAGE -NOTIFICATION OF CYCLONE WITHIN 72 HRS COUNTRY EMERGENCY RESPONSE GROUP RESPONSIBLE FOR: - PROVIDING SUPPORT, ADVICE & OFF- LOCATION ASSISTANCE TO LOCATION WHERE INCIDENT IN PROGRESS - NOTIFYING OPERATING COUNTRY NEXT OF KIN, AUTHORITIES, EMPLOYEES, CONTRACTING COMPANIES, DISPOSAL OF FATALITIES - NOTIFYING & LIASING WITH CRISIS RESPONSE TEAM DUTY LEADER - PROVIDING & CO-ORDINATING SPECIALIST SUPPORT - CO-ORDINATING RECOVERY FROM INCIDENT. - OBTAINING CLEARANCES FOR & ISSUING RELEASE TO NATIONAL MEDIA TIER 2 INCIDENT SUBSTANTIAL INCIDENT. EMERGENCY RESPONSE GROUP DUTY MANAGER'S DECISION TO CALL OUT EMERGENCY RESPONSE GROUP MEMBERS. ERG DUTY MANAGER MUST NOTIFY CRISIS RESPONSE TEAM DUTY LEADER. TYPICAL INCIDENT TYPES: - OIL SPILLS ABOVE TEIR 1 - CIVIL UNREST OR SECURITY BREACH - FIRE &/OR EXPLOSION - INJURY OR ILLNESS REQUIRING EVACUATION - CYCLONE WARNING-BLUE ALERT WITHIN 48 HRS - KIDNAP CRISIS RESPONSE TEAM RESPONSIBLE FOR: - PROVIDING STRATEGIC RESPONSE ASSISTANCE, SUPPORT & ADVICE TO THE EMERGENCY RESPONSE GROUP IN THE COUNTRY WHERE THE INCIDENT TAKING PLACE - NOTIFYING EXPATRIATE NEXT OF KIN, INTERNATIONAL AUTHORITIES SHARE HOLDERS, JOINT VENTURE PARTNERS & FINANCIAL INSTITUTIONS - CO-ORDINATING & APPROVING ALL MEDIA RELEASES, ISSUING INTERNATIONAL MEDIA RELEASE(S) - AUTHORISING EXTRAORDINARY EXPENDITURE - DECIDING ON COURSE OF ACTION & CO- ORDINATING REPATRIATION OF EXPATRIATE & FAMILIES IN THE EVENT OF CIVIL UNREST OR WAR - CO-ORDINATING RESPONSE TO KIDNAP & EXTORTION DEMANDS - PROVIDING LEGAL ADVICE & RESPONSE TIER 3 INCIDENT CRISIS SITUATION APPEARS LIKELY. CRISIS RESPONSE TEAM DUTY LEADER'S DECISION TO CALL OUT CRISIS RESPONSE TEAM. CRISIS RESPONSE TEAM DUTY LEADER MUST NOTIFY THE CHIEF EXECUTIVE OFFICER. TYPICAL INCIDENT TYPES: - MAJOR POLLUTION - OIL SPILL >1000 TONNES - INCIDENT LEADING TO LOSS OF A FACILITY - INCIDENT LEADING TO SIGNIFICANT FINANCIAL LOSS - KIDNAP OR EXTORTION / THREAT - INCIDENT LEADING TO MULTIPLE INJURIES OR A FATALITY - INCIDENT WHICH COULD LEAD TO INTERNATIONAL MEDIA INTEREST -CYCLONE WARNING - YELLOW ALERT WITHIN 12 HRS FIGURE-7.4 EMERGENCY CLASSIFICATION VIMTA Labs Limited, Hyderabad C7-14

161 Chapter-7 Additional Studies Emergency Response Procedures Minor Emergency To enable the appropriate level of response to be implemented, emergency incidents are to be categorized according to three levels as follows: Tier-1 (Minor Emergency) an event with no escalation potential, which can be controlled and contained by the action of personnel of Incident Response Team (IRT) at the incident site. In such cases of local alert, the ERG leader will be notified but the ERG is not called out. Some typical incidents are: Minor accident; Equipment damage; Medical evacuation (not very serious cases); and Minor fires Major Emergency Tier-II Emergency Events with escalation potential, depending on the effectiveness of the local response. These incidents may impact the entire site. For such type of incidents the installation manager assumes the charge of Incident Response Controller (IRC) and activates ERG who aide/guide the IRC in controlling the emergency situation. The country manager is notified on the same. Some typical incidents are: Substantial security incident; Multiple casualties; Cyclone flooding; Serious damage to man/machinery; Substantial fire; Cultural conflict, and Serious incident. Tier- III Emergency A crisis that requires assistance from external resources in order to save lives, minimize damage and to bring the abnormal situation back under control. These incidents have the potential to impact beyond ONGC site limit. In such cases, IRC activates the ERG who notify the country manager and Crises Response Team (CRT) in Head Office will be activated. The CRT would guide / aide the ERG in controlling the emergency situation. VIMTA Labs Limited, Hyderabad C7-15

162 Chapter-7 Additional Studies Some typical Tier-3 incidents are: Major fire/explosion; Evacuation of the rig/platform; Loss of the rig/platform; Fatality; and Terrorist attacks. For a major emergency, the ERG team will use the Emergency Control Centers (ECCs) to enable constant guidance / aide during emergency situation between the incident site, ERG and CRT Emergency Response Strategies Whenever there is an emergency, the response team is required to swing into action without losing time. Time is the essence of the immediate relief and rescue operations to save human life, to mitigate the impact on the environment and to safeguard commercial consideration. This DMP has been prepared keeping in mind the above fact and it is conceptually based on the Trigger Mechanism. The Trigger Mechanism envisages that on receiving signals of a disaster happening or likely to happen, all activities required for the mitigation process are energized and activated simultaneously without loss of any time. The primary objective of this mechanism is to undertake immediate rescue and relief operations and stabilize the mitigation process as quickly as possible. The main parameters of such a response plan include: Signal / Warning Mechanism; Activities and their Levels; Sub-activities; Command and Control Structure; Individual Roles and Responsibilities of each specified authority to achieve the activation as per response time; Response teams for each specified authority; Emergency Procedures; and Alternate Plans & Contingency measures Alert Phase It will be the duty of all site personnel at the site to remain alert at all times for hazardous situations that have the potential to escalate into an emergency incident. The ERG members would be activated as required. Emergencies on site can be initiated in a number of ways depending upon the severity of the incident i.e., by the site fire alarm siren, which any personnel on the incident site can activate. The site siren will sound in an intermittent mode. Also, the individual fire alarms will sound in the area of the incident. VIMTA Labs Limited, Hyderabad C7-16

163 Chapter-7 Additional Studies This procedure initiates the site fire and Rescue Department and Site Security into their standard procedures to attend the incident. This has the advantage of permitting the earliest possible action to be taken to control the immediate situation, which may avoid the development of a major emergency. The Incident Controller will attend the scene of the incident and the ERG Leader will be notified. Depending upon the severity of the emergency (Tier-2) the ERG Leader will activate the ERG and notify the Country Manager as appropriate. The incident controller will assess the situation from the edge of the incident scene to reduce the probability of personal injury. The ERG members will be on standby to go to the Emergency Control Centre (ECC). Evacuation of employees to the nearest assembly point or refuge may be required, if not hindered by fire or toxic cloud (all personnel present on the incident site would make it a point to always move upwind in case of fire) Preparedness for Emergencies Command by Competent Persons Effective command and control starts with a clear definition of the overall command and control structure and description of the duties of key personnel with specific responsibilities for emergency response. Number of Persons for Emergency Duties The command/control of emergencies must identify the minimum number of persons required to provide an adequate response to emergencies. This includes having staff trained and competent to fulfill the roles of other members of staff if they are not available. List of Persons for Emergency Duties A list of those staff that has emergency duties is displayed in the Control room. It is the responsibility of the ONGC Radio Officer would ensure that these lists are kept up to date Control of Emergencies The major systems for controlling emergencies and preventing escalation are detailed in subsequent sections of the DMP, which gives the emergency procedures to be followed in case of an impending/occurring disaster. It is absolutely necessary for the ERG leader to review the incident response and provide his inputs for improvements / modifications to the DMP and update accordingly. ERG leader would debrief all personnel involved in the emergency response action. It will be the responsibility of the ERG leader to develop a Post Emergency Action Plan with the assistance of Incident Controller. It will be the responsibility of the designated HSE personnel to prepare a complete incident report collating incident reports/ logs from the respondents and forward the same to higher authorities as appropriate. VIMTA Labs Limited, Hyderabad C7-17

164 Chapter-7 Additional Studies 7.4 Emergency Response Action Incident Control Centres (ICC) The Incident Controller will be responsible for co-ordinating the site response to any emergency and direct emergency response personnel as appropriate to the emergency. The installation manager s office shall be the designed ICC: At the drilling rig, it is suggested that the best location for control centre will be main control room and alternately it may be shifted to Temporary Refuge (TR) in case of major emergency. There will be radio, telephone or messenger contact with the ICC. The incident area will be tapped off and warning notices posted. The in-house Fire Team cordon off the incident area (Inner Cordon). Route markings from ICC to the incident to aid the emergency services will be arranged; Various personnel will wear fluorescent jackets with a description of their role. This will include the Incident Controller and medics. Emergency Control Centres (ECC) The Emergency Control Centre is to be set up by a person designated by the ERG office. The ONGC s Guesthouse (if available) could be the alternate ECC. It is place from where the operations to handle the emergencies are directed and coordinated. The centre is equipped to receive and transmit information and direction from and to the Incident Controller as well as from outside. ECC shall contain equipment for logging the development of the incident to assist the controllers determine any necessary action: The ICC and ECC should contain: An adequate number of external telephones. At least one will be ex-directory or capable of use for outgoing calls only. This will avoid the telephone switchboard being overloaded with calls from anxious relatives, the press etc; An adequate number of internal telephones; Radio equipment; A plan or plans of the works to show Areas where there are large inventories of materials, including oil storage, drilling materials; Sources of safety equipment; The fire water system and additional sources of water; Stocks of other fire extinguishing materials; VIMTA Labs Limited, Hyderabad C7-18

165 Chapter-7 Additional Studies Assembly points, casually treatment centres; Location of the works in relation to the surrounding community; and Lorry/truck parks. Additional plans which may be marked up during the emergency to show i Areas affected or endangered; ii Deployment of emergency vehicles and personnel; iii Areas where particular problems arise; iv Area evacuated; and v Other relevant information HAZCHEM sheets for the various hazardous materials used on-site; Note pads, pens, pencils to record all messages received and sent by whatever means; Nominal roll of employees or access to this information; List of key personnel, addresses and telephone numbers. Emergency Control Centre is located, designed and equipped to remain operational in an emergency. 7.5 Emergency Response Procedures Blowout During a blowout, the Rig (specific) emergency Response Plan would be referred. The contingency plan for onshore blowout (drilling rig) is given in Figure-7.5. Common steps required during blowout are discussed as below: Driller/person on the spot In case, the kick is timely detected In case of string at the bottom of hole 1 Lift and clear tool joint out of rotary and stop pumps; 2 Close BOP and choke; 3 Record Shut In Drill Pipe pressure (SIDP) and Shut In Casing Pressure (SICP); and 4 Prepare kill sheet and make calculations for standard well killing procedures; In case of while making trip: 1 Stop tripping operations; 2 Position tool joint at rotary table and set slips; 3 Install safety valve and close safety valve; 4 Open choke line; 5 Close BOP and choke; 6 Make up Kelly; VIMTA Labs Limited, Hyderabad C7-19

166 Chapter-7 Additional Studies 7 Record shut in SIDP and SICP; and 8 Prepare the kill sheet and make calculations for standard well killing procedure. In case of string out of the well: 1. If well condition permits attempt run in hole and whenever situation is critical shut the well by following steps as mentioned in case of while making trip; and 2. If the trip in is not possible then use volumetric method off well control. FIGURE-7.5 CONTINGENCY PLAN FOR ONSHORE BLOWOUT (DRILLING RIG) VIMTA Labs Limited, Hyderabad C7-20

167 Chapter-7 Additional Studies In case of sudden kick: 1 Close the BOP; 2 Record SIDC & SICP; and 3 Prepare kill sheet and make calculations for standard well killing procedure. On detection of a kick the Senior Tool pusher/drilling supervisor is to be informed immediately; and Person discovering the blowout should notify radio room of the incident. Radio Room Alert to the fire team; Notify Incident Controller of the incident to clear non-essential traffic; and Send radio and other communications on instructions from Incident Controller Drilling Supervisor/PIC Minimize ignition sources; Assess the situation along with Senior Tool pusher and declare the incident to be: Minor event, which can be brought under control using in situ equipment Serious event, which may not be brought under control; and Major event, in which the well is unlikely to be brought under control Incident controller to be informed immediately if the event is classified as serious or major event; and Instruct control room to suspend drilling operations Incident Controller Inform to the ERG Leader, provide full details and likely requirements and maintain contact; Activate site response personnel as appropriate, provide full incident briefing and likely requirements and maintain liaison; Ensure that Fire team is on standby; Instruct to all non-essential personnel to prepare for evacuation. In a major emergency, an order for total evacuation must be given; After situation has returned to normal, inspect incident site to determine whether further corrective action is required to make situation safe. ERG Leader Obtain full incident briefing and likely requirements from Incident Controller and maintain liaison; Active ERG appropriate contact Directory; Notify EMT Leader and provide full incident briefing and likely requirements; Co-ordinate support activities as required; VIMTA Labs Limited, Hyderabad C7-21

168 Chapter-7 Additional Studies Determine need for external assistance for safety of personnel, well control and pollution prevention; Well Control The following preventers are stacked in a sequence and this assembly of preventers is termed as BOP Stack as shown in the Figure 7.6. Blowout Preventers: Blow out Preventer consists of Annular Preventer, which can generally close on any size or shape of tubular in the well bore which closes the annular space between drill string and casing. 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. Blowout prevention equipment shall be installed, tested and operated according to the Well Control Manual for Drilling Operations. Certain key personnel on the drilling unit shall hold a valid certificate of examination from a recognized pressure control course. The BOP stack in use shall be pressure tested initially before drilling out of the casing shoe and thereafter weekly. A sequence of successful tests indicate that greater confidence could be placed in the stack and control equipment, then the testing interval can be extended up to a maximum of two weeks. All pipe fittings, valves and unions placed on or connected to blow-out prevention equipment, well casings, casing head housing, drill pipe or tubing shall have a working pressure rating at least equivalent to that of the component to which it is fitted. Drilling operations shall not proceed until blowout prevention equipment is found to be serviceable by visual inspection and appropriate pressure testing. BOP control systems are installed, tested and operated according to the Well Control Manual for Drilling Operations. In addition to the instrumentation to indicate the availability of air pressure and fluid pressure, the following safety features will be considered for the control systems: A relief valve installed; accumulator low-pressure alarm; air-driven hydraulic fluid charge pumps; electric-driven hydraulic pump to be connected to the emergency generator; fail safe regulators; manifold pressure is consistent with ram closing force requirements at anticipated maximum surface pressure (high pressure wells); accumulator capacity at elevated manifold pressures still meets requirements; fire resistant hydraulic control hoses and control fluid; appropriate location of remote operating panels; redundant functions plugged off; hydraulic control hose are tested to the rated pressure of the unit. VIMTA Labs Limited, Hyderabad C7-22

169 Chapter-7 Additional Studies Hydrogen Sulphide (H2S) Natural gas leaks are expected regardless of the location. Natural gas is an extraneous material. As such all natural gas leak carry the risk of fire and explosion until the leak is contained. Hydrogen sulfide is a toxic chemical gas frequently found in natural gas deposits. During drilling operations, the consequences of leaks or kicks with sour gas or crude can be very serious. Personnel can be incapacitated by relatively low concentrations of H2S in a very short time and equipment can suffer catastrophic failure due to H2S embrittlement. A contingency plan will be drawn up when H2S may be expected during well operations. A study will be made of the geological and geographical features of the area, in order to predict the expected areas where H2S may be encountered or may accumulate. Information about the area and known field conditions, including temperatures, pressures, proposed well depth and H2S concentrations will be obtained and taken into consideration. The drilling program will highlight this hazard and give details of controls and recovery measures in place. Once the cellar has been excavated, the drill pad constructed and equipment set in place, drilling can commence. Typically, at the time of site construction, a false conductor of large diameter will be grouted upto 3.5 m from surface. Initially, the drilling fluid used is quite often water alone. Drilling will then continue for several hundreds of meters. At this depth smaller diameter casing is usually cemented into the hole. This intermediate casing protects the well by sealing potentially weak zones. At this stage low density drilling muds will be used and although it is unlikely that gases or fluids under pressure might be encountered, a blowout preventer is typically installed to prevent fluid from the formation gushing to the surface. Drilling continues using progressively smaller bits and incrementally decreasing casing diameters. Changes in mud composition, and drill bit, are likely to occur according to the different strata encountered. Annular BOP Pipe Ram Shear Ram Coeflexip Hose to Choke Moni-Fold KILL Line FIGURE-7.6 TYPICAL SCHEMATIC OF BOP STACK VIMTA Labs Limited, Hyderabad C7-23

170 Chapter-7 Additional Studies Abandonment of Rig/Well In case of major incident, which necessitates the abandonment of the rig/well, the following actions will be taken; Emergency Siren Modes Fire High/Low tone Proceed to muster point(s) Evacuation On/off monotone Evacuate as directed All clear Continuous monotone Emergency ended Control room will activate Emergency Siren upon fire Call Point or ESD being activated. Personnel can also alert Control Room by radio or phone Rig/well PIC Notify Radio Room of intention to abandon the rig Ensure that rig facilities are cleared for evacuation (e.g. clear equipment from heli-deck etc); Determine appropriate safe method of abandonment and notify all personnel to assemble at appropriate Muster Point; Contact Incident Controller to provide full incident briefing and likely requirements and maintain liaison; and Instruct all personnel to evacuate the rig. All Other Personnel of Rig On hearing alarm, put on life jacket and proceed to Muster Point nominated by Rig PIC, remain calm and await instructions; and If evacuating by jumping into buddy up and tie off if possible any try to stay together with as many people as possible. Radio Room On receiving emergency call, nominate a dedicated frequency for the emergency calls; Notify Incident Controller and advise of emergency frequency and update frequently; Inform all ONGC radio stations of incident and ask to clear non-essential traffic; and Send radio and other communications on instructions of Incident Controller. HSE Support Conduct headcount of personnel assembled at Muster Point; Notify Incident Controller of headcount/token results and emphasize on any discrepancy; Ensure that headcount is updated if people are allocated tasks that remove them from Muster Point (e.g. fire team etc); and For any discrepancy in headcount, reconcile daily record of persons on site with lists of persons assembled at Muster Points and notify Incident Controller of identify of missing person(s). VIMTA Labs Limited, Hyderabad C7-24

171 Chapter-7 Additional Studies Incident Controller Obtain full incident briefing and likely requirements from RIG PIC and maintain liaison; Ensure that all production is shut in and that all machinery is rendered safe; Ensure that all personnel are accounted for via headcount as SAR is conduct for any missing persons; Obtain a personnel list on the affected rig; and Notify ERG Leader of rig evacuation and any likely requirements ERG Leader Obtain full incident briefing and likely requirements from Incident Controller an maintain liaison; Activate ERG with appropriate Contact Directory Notify EMT Leader and provide full incident briefing and likely requirements; and Co-ordinate support activities as required Structural Damage/Failure of the Rig The actions to be taken during a structural damage/failure of the rig/well are as follows: Drilling Supervisor/PIC Notify Radio Room of incident; Instruct Site Control Room to shut the drilling operation if required; Inspect any damage/failure sustained by rig, if safe to do so, assess actions required to make rig safe; Ensure that all personnel are accounted for and consider need for evacuation; and Contact Incident Controller to provide full incident briefing and likely requirements and maintain liaison. Radio Room Call support vessel to affected rig if required; Notify Incident Controller of incident and update as further communications received; Inform all ONGC radio stations of incident and ask to clear non-essential traffic; and Send radio and other communications on instructions from Incident Controller. Incident Controller Obtain full incident briefing, and likely requirements from Drilling Supervisor/PIC and maintain liaison; Ensure that all personnel have been accounted for; Ensure that drilling activity has been stopped if appropriate; Notify ERG Leader, provide full incident briefing and likely requirements; VIMTA Labs Limited, Hyderabad C7-25

172 Chapter-7 Additional Studies Proceed to affected part of the rig for damage assessment and depending on severity of damage, suspend drilling operations, make all equipment secure and restrict access until repairs can be undertaken; To assess and declare the incident to be a minor, serious or major event; and To consider evacuation of non-essential personnel and depending on the severity of the incident, the evacuation of all personnel. ERG Leader Obtain full incident briefing and likely requirements from Incident Controller and maintain liaison; Activate ERG with appropriate Contact Directory; Notify EMT Leader and provide full incident briefing and likely requirements; and Activate technical support as appropriate for evaluation and control of situation. All response Members Maintain log of events for collection at end of incident Well Control Emergencies Person first on scene Notify radio Room of incident; Follow appropriate well control procedure; Instruct all non-essential personnel if any to proceed to Muster Point(s); conduct headcount(s) as required; Ensure that all possible ignition sources on affected platform are turned off; Determine source of the problem and safest & most effective way to prevent incident from escalating; Ensure that wire line crew are advised/aware of any incident and likely requirements; Contract Incident Controller to provide full incident briefing and likely requirements, Maintain liaison. Radio Room Notify Incident Controller, Production Supervisor and Petroleum engineer of incident; update as further communications received; Inform all ONGC radio stations of incident and ask to clear non essential traffic; Send radio and other communications on instructions from Incident Controller. Incident Controller Obtain full incident briefing and likely requirements from Wire line and/or site Supervisor, Maintain liaison; For wire line incident, ensure that drilling supervisor and petroleum engineer is notified; Consider need to evacuate platform, if any, request results of any headcount and ensure that all personnel are accounted for conduct SAR for any missing personnel; and VIMTA Labs Limited, Hyderabad C7-26

173 Chapter-7 Additional Studies ERG Leader Obtain full incident briefing and likely requirements from Incident Controller. Maintain liaison Activate ERG with Contact Directory as required; Notify wire line contactor management and maintain liaison; Determine need for external assistance for safety of personnel, well control and pollution prevention; Activate pollution control procedures as required; Liaise with support co-ordinator to activate well control specialties and equipment to incident site as required; Consult with Incident Controller and Wire line Supervisor regarding safest, most effective way to resolve incident. All Response Member As time permits, maintain log of events for collection at end of incident Fire On Rig Person first on scene Shut down production by activating ESD; Close down any manual feed valve that may be feeding the fire, if safe to do so, Notify Radio Room on incident; Attempt to extinguish the fire with portable equipment, if safe to do so; and Contact Incident Controller to provide incident briefing and any likely requirements. Radio Room Alert Fire Team of incident, Notify Incident Controller of incident and update as further communications received; Inform all radio stations of incident and ask to clear non-essential traffic; and Send radio and other communications on instructions from Incident Controller. Rig PIC (if any maintenance/survey team is on the platform) Instruct Control room to shutdown activities from affected rig; Instruct all non-essential personnel, if any to proceed to Muster Point and conduct headcount as required; and If fire cannot be extinguished safely, consider need for evacuation (if any) of rig. Incident Controller Activate site response personnel as appropriate and provide full incident briefing and likely requirements. Maintain liaison; VIMTA Labs Limited, Hyderabad C7-27

174 Chapter-7 Additional Studies If fire extinguished, ensure that there is no gas leak. If gas leak detected, and if safe to do so, shut off all ignition sources, close all relevant shut-off valves and evacuate rig; Notify ERG Leader, provide full incident briefing and likely requirements; After situation has returned to normal, inspect incident site to determine whether further corrective action is required to make situation safe. ERG Leader Obtain full incident briefing and likely requirements from Incident Controller. Maintain liaison; Activate ERG with appropriate Contact Directory; Notify EMT Leader and provide full incident briefing and likely requirements; and Co-ordinate support activities as required. All Response Members As time permits, maintain log of events for collection at end of incident Rig Evacuation Person on Rig Notify Radio Room of intention to abandon the rig Ensure that platform/rig facilities are cleared for evacuation; Determine appropriate safe method of abandonment and notify all personnel to assemble at appropriate Muster Point Contact Incident Controller to provide full incident briefing and likely requirements. Maintain liaison; Instruct all personnel to evacuate the platform / rig; Put on a lifejacket and proceed to Muster Point nominated by rig PIC. Remain calm and await instructions; and If evacuating by jumping into the water, buddy up and tie off, if possible, try to stay together with as many people as possible. Radio Room On receiving emergency call, nominate a dedicated frequency for the emergency calls; Notify Incident Controller and advise of emergency frequency and update frequently; Inform all radio stations of incident and ask to clear non-essential traffic; and Send radio and other communications on instructions from Incident Controller. Incident Controller Obtain full incident briefing and likely requirements from rig PIC and maintain liaison; Ensure that all activity is shut in and that all machinery is rendered safe; VIMTA Labs Limited, Hyderabad C7-28

175 Chapter-7 Additional Studies Ensure that all personnel are accounted for via headcount and SAR is conducted for any missing persons; Obtain a personnel list for the affected rig; and Notify ERG Leader of platform evacuation and any likely requirements. ERG Leader Obtain full incident briefing and likely requirements from ERG Leader and maintain liaison; Activate ERG with appropriate contact directory; Notify EMT Leader and provide full incident briefing and likely requirements; and Co-ordinate support activities as required; All Response Members As time permits, maintain log off events for collection at end of incident Gas Release on Rig Person Discovering Release Avoid creating any source of ignition; Shutdown platform/rig by activating ESD; If the location of the leak is known, and if safe to do so, shut any relevant manual valves; Notify Radio Room of incident; and Inform radio room of incident Rig PIC Stop all hot work and shutdown all other sources of ignition; If safe to do so, attempt to locate and shut off the source of the leak; and Contact Radio Room/Incident Controller to provide full incident briefing and likely requirements. Maintain liaison. Radio Room Notify Incident Controller of incident and update as further communications received; Notify Drilling Supervisor, if appropriate; Inform all radio stations of incident and ask to clear non-essential traffic; and Send radio and other communications on instructions from Incident Controller; Incident Controller Obtain full incident briefing and likely requirements from radio room and maintain liaison; Instruct Site Control Room to shut in production, if required; Ensure that all personnel are accounted for and consider need to evacuate that all personnel are accounted for and consider need to evacuate non-essential VIMTA Labs Limited, Hyderabad C7-29

176 Chapter-7 Additional Studies personnel (in case team is present on the platform). Evacuate all personnel if gas concentration reaches danger level; Notify ERG Leader and provide full incident briefing and likely requirements. ERG Leader Obtain full incident briefing and likely requirements from Incident Controller and maintain liaison; Activate ERG with appropriate Contact Directory; Notify EMT Leader and provide full incident briefing and likely requirements; and Co-ordinate support activities as required. All Response Members As time permits, maintain log of events for collection at end of incident Structural Damage Rig PIC In case of any maintenance/survey team is present on the rig. Notify Site Radio Room of Incident; Instruct site controller room to shut in production if required; Inspect any damage sustained by rig, if safe to do so and assess actions required to make rig/platform safe; Ensure that all personnel are accounted for and consider need for evacuation, if any, and Contact Incident Controller to provide full incident briefing and likely requirements, Maintain liaison. Site Radio Room Notify Incident Controller of incident and update as further communications received; Inform all radio stations of incident and ask to clear non essential traffic; and Send radio and other communications on instructions from Incident Controller. Incident Controller Obtain full incident briefing including status of any instrument, which may have collided with the rig/platform, and likely requirements from site radio room. Maintain liaison; Ensure that support vessel proceeds to affected platform if required; Ensure that production on the affected rig/platform has been shut in; Notify ERG Leader and provide full incident briefing and likely requirements; and Proceed to affected platform for damage assessment and depending on severity of damage, keep production shut in, make all equipment secure and restrict access until repairs can be undertaken. VIMTA Labs Limited, Hyderabad C7-30

177 Chapter-7 Additional Studies ERG Leader Obtain full incident briefing and likely requirements from Incident Controller and maintain liaison; Activate ERG with appropriate Contact directory. Notify EMT Leader and provide full incident briefing and likely requirements; and Activate technical support as appropriate for evaluation and control of situation; All response Members As time permits, maintain log of events for collection at end of incident Ground Movement Any Person Establish the severity of the movement; Drilling/production Supervisor/PIC is to be alerted as the movement is detected; and Contact Site Radio Room and notify the incident Site Radio Room Inform the Incident Controller Inform all radio stations of incident to clear non essential traffic; and Send radio and other communications on instructions from Incident Controller; Drilling/Production Assess the situation; Drilling/production to be suspended; and Inform the Incident Controller and to be informed immediately if the event is classified as serious or major. Incident Controller Obtain full status briefing from the Drilling/production supervisor/pic and maintain continuous contact; Ensure that support are proceeded to the rig/platform if required; Ensure the safety of all personnel; Consider evacuation if it is required depending upon the severity of the situation; Contact ERG leader and provide details of the situation; and Proceed to carry out damage (if any) assessment and take control measures as required; ERG Leader Obtain full incident briefing and likely requirements from Incident Controller and maintain liaison; VIMTA Labs Limited, Hyderabad C7-31

178 Chapter-7 Additional Studies Activate ERG with appropriate Contact directory; Notify EMT Leader if required and provide full incident briefing and likely requirements All Response Members Maintain log of events for collection at end of incident Un-ignited Gas Release Person discovering Fires Avoid creating any source of ignition; Shutdown drilling by activating ESD; If location of the leak is known, and if safe to do so, shut any relevant manual valves; Notify Site Radio Room of incident; and Contact Incident Controller to provide incident briefing and any likely requirements. Site Radio Room Alert Fire Team of incident; Notify Incident Controller of incident and update as further communications received; Inform all radio stations of incident and ask to clear non-essential traffic; Send radio and other communications on instruction from Incident Controller. Incident Controller Stop all hot work and shutdown all other sources of ignition; Instruct Site Control Room to shut in production, if appropriate; Evacuate all non essential personnel and ensure that alternate Muster Point advice is given if a gas release threatens Primary Muster Point; Evacuate all personnel, if gas concentration reaches danger level; If safe to do so, organize for location and shut off of leak source; Ensure that system is depressurized to flare/atmosphere as appropriate; Notify ERG Leader, provide full incident briefing and likely requirements and maintain liaison; Ensure that all personnel have been accounted for and ensure that nonessential personnel stay clear of incident site and initiate SAR for any missing persons; Notify ERT Leader provide full incident briefing and likely requirements ERG Leader Obtain full incident briefing and likely requirements from Incident Controller and maintain liaison Activate part or all of ERG as appropriate; Notify EMT Leader and provide full incident briefing and likely requirements; and Co-ordinate support activities as required; VIMTA Labs Limited, Hyderabad C7-32

179 Chapter-7 Additional Studies All Response Member As time permits, maintain log of events for collection at end of incident Hydrocarbon Spill Equipment and Training Assure emergency dispersant and spray equipment for dealing with spills is readily available; and Assure personnel are trained in use of emergency dispersant and spray equipment, and with the provision of this procedure. Oil Spill Detection Be alert during operations such as fuel oil transfer and critical drilling operations that could result in oil spills; Keep watch on the transfer pump, manifolds, transfer hoses, and all other connections; During critical drilling operations, keep watch on the drilling equipment instrumentation and stop drilling when unsafe conditions arise; and Shut Down the Source Review site for safety hazards; Stop the spill at the source as quickly as possible; Assure that transfer pumps are immediately stopped if spill occurs during fuel oil transfer; and If the spill occurs from any equipment on either vessel, shut down the operating equipment and close any valves between the leak source and the equipment. Oil Spill Reporting Spills should be reported using the Pollution Report Form. Oil Spill Contingency Plan Detailed oil spill response actions are included in Oil Spill Contingency Plan (OSCP) Medical Evacuation The incidents that may require medical evacuation are mainly severe casualties. The actions to be taken during medical evacuation are as following: Incident Controller Determine need for Medevac and type and special conditions of transport required. Consult with Site doctor regarding appropriate action and maintain liaison; Consult with Site doctor on appropriate destination for serious Medevac; VIMTA Labs Limited, Hyderabad C7-33

180 Chapter-7 Additional Studies If patient is a contractor, contact contractor manager and provide full Medevac details; and Notify ERG Leader and provide full incident briefing and likely requirements. Name of ill/injured person(s) to be communicated secure communications. ERG Leader Obtain full incident briefing and likely requirement from Incident Controller and maintain liaison; Activate ERG as appropriate; Liaise with aircraft operator and airport authorities to facilitate medevac and ensure that site representative is at airport to accompany patient to hospital; If required, obtain permission for hospital ambulance to access airport security zone. If access denied, ensure that airport ambulance should be available for transfer to hospital ambulance; Notify next of kin; If patient is a contractor, ensure that contractor manager is informed with full Medevac details; and Maintain liaison with patient and patient s family until discharged and consider arranging for relatives of injured person to be brought to hospital. All Response Members Maintain log of events for collection at end of incident Criminal Acts Incident Controller Take actions to detain offender(s) if, appropriate; Notify ERG Leader and provide full incident briefing for the following: Nature of crime; Identify of person(s) involved; Extent of any injury to personnel and if Medevac required Any assistance required; and Action taken to date If person(s) have been taken into custody, determine with ERG Leader the need to involve Police and contact Police as appropriate: Secure evidence, close off incident site, prepare sketches and photographs, identify witnesses and take statements; Consider need for suspension of any impending crew change; Consider restriction of information to need-to-know basis; and Assist Police with their inquires. ERG Leader Obtain full incident briefing and likely requirements from Incident Controller and maintain liaison; Activate ERG as appropriate; Notify EMT Leader and provide full incident briefing and likely requirements; and VIMTA Labs Limited, Hyderabad C7-34

181 Chapter-7 Additional Studies Submit reports to relevant authorities All Response Members Maintain log of events for collection at end of incident Bomb Threat/Extortion If there is a contingency like bomb threat/extortion attempt then the following procedures would be followed: Person Receiving Threat For written threat, keep all paper, envelopes etc. to preserve as evidence; For verbal threat, use bomb threat checklist while talking to the person making threat and write details notes checklist not available; Do not use radio to raise alarm radio signals may trigger an explosive device For verbal contact, be calm and respectful and DON T PANIC; Take threat seriously; Signal for assistance if in a position to do so; Pay attention to what is being said and to any background noise; Accurately write all that is being demanded and ask calmly for confirmation if unclear; Do not agree or concede to any demands without prior approval; Try to keep caller talking as long as possible and DON T HANG UP; If caller hangs up, do not hang up your phone (it may be possible to trace call); and At the conclusion of the call, check all notes taken to ensure accuracy. Incident Controller Immediately shut in all drilling/production activities if appropriate; Notify ERG Leader and provide full incident briefing and likely requirements; Evacuate all non-essential personnel to a safe area and consider total evacuation as required; Ensure that all relevant authorities (e.g. Police etc) are notified immediately; Ensure that bomb threat checklist is completed by person receiving a verbal threat; Make every effort to calm all involved and don t aggravate situation by personal attempts to resolve situation hastily; Ensure that someone is continually standing by a phone to receive next communication from extortionist or ensure that alternative number is provided to caller; and Await assistance from appropriate authorities. ERG Leader Obtain full incident briefing and likely requirement from Incident Controller and maintain liaison; Activate ERG as appropriate; Ensure that all relevant authorities (e.g. Police etc.) are notified immediately; VIMTA Labs Limited, Hyderabad C7-35

182 Chapter-7 Additional Studies Liaise with relevant Government agencies to obtain assistance (e.g. Indian Armed forces etc) as required; and Notify EMT Leader and provide full incident briefing and likely requirement. All Response Members Maintain log of events for collection at end of incident 7.6 End of Emergency Prior to termination of an emergency, the following issues would be considered and necessary action taken: Confirm that the emergency is concluded; List of resources that are required for on going incident control (if appropriate); Final information release and/or notification to o o o o o o o o o o o o o o o o Site incident response personnel, ERG, EMT and Chairman; Consultants; Contractors; Customers; Emergency services; Employees State Regulatory Authorities; National Regulatory Authorities Environmental Agencies Joint Ventures; Local Communities; Neighbour / third parties Pressure groups Suppliers Trade unions; and Media De-briefing of all personnel (including people currently relieved or stood down); Close down additional security arrangements; Finalize additional catering and other services; Continuing counselling for those involved in the incident; Compile and file all documents relating to the response; Arrange for full incident investigation and analysis; Carry out follow up review to ascertain effectiveness of Callout; Site incident Response, ERG and EMT Functions; Operational emergency response; Approve / comment on incident debriefing reports and recommended actions; and Recommended revision of Emergency Plans as required. 7.7 Communications All nominated and dedicated emergency response stall will carry VHF radios programmed with the relevant Watch Keeping / Emergency Frequency. VIMTA Labs Limited, Hyderabad C7-36

183 Chapter-7 Additional Studies Communication Network It is essential that all emergency communications will be relayed to the Incident Controller (or Alternate) and/or the ERG leader (or alternate as soon as possible in case of an emergency situation. As far as possible all Emergency Calls from site, helicopter and base station would be passed on through the site Radio Room. The Radio Operator will allocate a dedicated emergency frequency and will advise the Incident Controller of the emergency situation and frequency. Upon the commencement of an emergency, the Radio Operator will inform radio stations that there is an emergency and ask to clear all non essential radio traffic on the designated emergency radio channel/frequency for communications. If an incident occurs after normal business hours, the Site Radio Room will make contact with all Radio rooms, which will in turn activate the ERG Leader and other personnel as advised. VIMTA Labs Limited, Hyderabad C7-37

184 Chapter-7 Additional Studies REFERENCES 1. Offshore Blowouts, Causes and Control Per Holand, gulf Publishing Company 2. Comparative Safety Evaluation of Arrangements for Accommodating Personnel Offshore Report ref. OTN December 1998, OCB/Technical 3. A 100 well study of offshore blowout causes E.Dahl and T.I.Beru, Hydrocarbon Leak and Ignition Database 1992, E and P Forum 5. Techniques for Assessing Industrial Hazards, A Manual, World Bank, Technical Paper number 55, Technica Ltd, Study on Offshore Installations Protection against Impact, J.P.Kenny, Risk Assessment of Buoyancy Loss, Case Study I Report 6 of RABL Project, Siktech, OREDA-92 Offshore Reliability Data Handbook 2 nd Edition 9. The Offshore Installations (Safety Case) Regulations Analysis Methods and Inservice Experience-submersible Platforms C.A.Carlsen and S.Knudsen, Mobile Platform Stability. Sub-project 0.6, Estimation of Damage Conditions. Det Norske Veritas, Worldwide Offshore Accident Databank Statistical Report 1996, Det Norske Veritas 13. Assessment Principle for Offshore Safety Cases HSG 181, HSE Books, International Association of Drilling Contractors, Accident Statistics Program, E&P Forum, Accident data, UK Department of the Oil and Gas Reserves of the United Kingdom (The Brown Book), 1990; 17. Norwegian Petroleum Directorate, Annual Report, Health and Safety Executive, Parloc 92. The update of Loss of Containment Data for Offshore Pipelines; prepared by Advanced Mechanics and Engineering Limited for the Health and Safety Executive, Results taken from BP CIRRUS Consequence Modeling Software Package 20. SINTEF Offshore Blowout Database E&P Forum, Risk Assessment Data Directory, J.P.Kenny Protection of Offshore Installation against Impact Report OTI 88535, Scand Power Model for Blowout Prediction Feb, 1995 VIMTA Labs Limited, Hyderabad C7-38

185 Chapter-8 Project Benefits 8.0 PROJECT BENEFITS The proposed exploration program will establish hydrocarbons in the block. The development of the oil field will result in considerable growth of service sector and will also generate new industrial and business opportunities in the area. Small and medium scale industries may be developed as consequence. 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. The commercial development will also lead to investment in Mizoram, bringing oil and gas revenues both to the State and to the Central Government. The presence of ONGC in the region will substantially improve the socio-economic conditions of the region. In Operation phase, ONGC will require 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. The expenditure towards CSR activities by ONGC is enclosed as Annexure-XI. 8.1 Improvements in the Physical Infrastructure The beneficial impact of hydrocarbon development on the civic amenities will be substantial after the commencement of project activities. The basic requirement of the community needs will be strengthened by extending health care, educational facilities to the community, building/strengthening of existing roads in the area. ONGC will initiate the above amenities either by providing or by improving the facilities in the area, which will help in uplifting the living standards of local communities. The construction of new roads in the project area will enhance the transportation facilities. With improved transportation facilities there is always a scope for development. 8.2 Improvement in the Social Infrastructure Generation of employment: The project will create opportunities for direct and indirect employment; Increase in purchasing power and improved standard of living of the area; Establishment of small and medium scale industries may be developed as consequence; Increased revenue to the state by way of royalty, taxes and duties; Regular Fund flow to local market; Overall Growth of the neighboring Area viz.: Agriculture and Animal husbandry; Health and family welfare; Watershed development; Sustainable livelihood and strengthening of village Self Help Groups; and Infrastructure development. VIMTA Labs Limited, Hyderabad C8-1

186 Chapter-8 Project Benefits In addition to above, due to increase in purchasing power of local habitants: There shall be significant change in the socio-economic scenario of the area; The proposed project shall enhance the prospects of employment; Recruitment for the unskilled and semiskilled workers for the proposed project will be from the nearby villages; The basic amenities viz., roads, transportation, electricity, proper sanitation, educational institutions, medical facilities, entertainment, etc. will be developed as far as possible; and Overall the proposed project will change living standards of the people and improve the socio-economic conditions of the area. 8.3 Employment Potential The impact of the project on the economic aspects can be clearly observed. The proposed project activities will provide employment to persons of different skills and trades. The local population will be given preference to employment. The employment potential will ameliorate economic conditions of these families directly and provide employment to many other families indirectly who are involved in business and service oriented activities. The employment of local people in primary and secondary sectors of project shall upgrade the prosperity of the region. This in-turn will improve the socio-economic conditions of the area. During construction phase of the project, this project will provide temporary employment to many unskilled and semi-skilled laborers in nearby villages; This project will also help in generation of indirect employment to those people who render their services for the personnel directly working in the project; and In case the hydrocarbon is established in the block, considerable number of people will be benefited by provision of services to the residents in for of employment opportunities. Thus, the direct and indirect employment generation by this project. The present trend of out migration for employment is likely to reduce due to better economic opportunities available in the area. During the construction phase about people on average per day will be employed for a period of one year. The ONGC Corporate EHS policy is given in Annexure-XII. VIMTA Labs Limited, Hyderabad C8-2

187 Chapter-9 Administrative Aspects 9.0 ADMINISTRATIVE ASPECTS 9.1 Operational Philosophy The activities proposed for the proposed exploratory drilling programme shall be in complete compliance with all applicable Laws, Regulations, Standards and Permits, the Production Sharing Contract (PSC), procedures, specifications, rules, standards and guidelines. In order to achieve this, the drilling operations will be maintained by technically qualified and experienced people. Detailed procedures and plans will be developed for each activity prior to operations start up. All persons on board for the drilling rig will be experienced crew with valid qualifications. Besides compliance to regulatory framework, the primary operational objectives are that all operations shall be consistently operated in a manner that causes neither threat nor harm to people or the environment. The methods used to operate and maintain the assets shall not cause damage to either the installed facilities or the local infrastructure, whilst at the same time consistently providing a production availability level that meets the target demand. Operational requirements are primarily based on global best practice, lessons learned and experiences transferred from ongoing operations and provide the criteria for operation verification in both design and fabrication. Verification of design and fabrication will be a significant feature of the development to ensure operation requirements are appropriately incorporated; these should include but are not limited to: Operating HSE performance will be duly considered and consistently incorporated into design; Maximum life-of-asset value will be sought through design selections that optimally integrate capital and operating costs; and Operations staff will become highly competent and knowledgeable of the design and operations details in advance of start-up, in order to more safely and efficiently support commissioning and better prepare themselves for the initial and longer term operations. The HSE Management System Process which will be developed for use as part of the implementation of the Operations Philosophy will be followed, together with the commitments. Continuous Improvement (CI) is a key consideration of the Philosophy and will be achieved by measures that will include bench-marking, use of key performance indicators, the application of structured competency assessment and competency improvement training programs for personnel involved in operations activities, the progressive introduction of Improvement Teams, as well as enhancement of the breadth, level and quality of local support through a Local Content Development Plan. VIMTA Labs Limited, Hyderabad C9-1

188 Chapter-9 Administrative Aspects 9.2 Health Safety and Environment HSE Management System The Group HSE Management System describes how ONGC manages health, safety, environment, security and corporate social responsibility risks within business activities, in order to meet the commitments in the Group HSE, Security and CSR policies. The aims and objectives of the Group HSE Management System are to: Enable risk identification and management; Provide clear definition of roles and responsibilities; Stimulate high levels of ownership throughout the organization; Promote empowerment and not discourage innovation; and Identify mandatory control processes both at Group level and within the operating subsidiaries. The goal being for ONGC to assure itself and other stakeholders that all operations are reflective of good industry HSE practice and is able to comply with Company Policy and legislation through a process of self regulation and control. The emphasis is placed on an approach which is: Objective setting (establishing what to do and then doing it); Proactive (taking action before and not after the event); and Risk-based (measures taken are necessary and cost effective to reduce risk to acceptable levels, at which the cost of further risk reduction is disproportionate to the benefit gained) Key Elements of Safety Plan An area plan will be devised by the HSE team in the region to make the system much more specific and appropriate for the asset and the types of activities being carried out. This will be communicated to all members of staff via training, inductions and regular safety meetings. All visitors to site will be inducted and told what part they play in maintaining safety whilst they are on site. The following topics are included in the HSE Management System: Leadership & Commitment; Policy & Strategic Objectives; Organisation, Resources and Documentation; HSE Risk Management; Planning & Procedures; Compliance & Regulations; Emergency Preparedness; Implementation & Monitoring; and Auditing & Review. VIMTA Labs Limited, Hyderabad C9-2

189 Chapter-9 Administrative Aspects Emergency Response Emergency response teams will be made up from operations personnel, who can be called upon 24 hours a day, supported by an Incident Management Centre (IMC) manned by operations senior management field personnel as and when required. There will also be a dedicated fire and emergency team out with the routine operations personnel. The fire and emergency response teams will receive specific training for their roles and will be drilled and exercised on a regular basis, as described in the Site Emergency Response Plan Safety Case The details of how HSE will be managed on site are contained within the stand alone HSE plan that will be developed by the HSE team in conjunction with the operations team management. In summary the following key points are the core of the HSE philosophy. The Safety Report will be a document prepared by ONGC Ltd. and will provide information that will demonstrate that all measures necessary for the prevention and mitigation of major accidents have been taken. The Safety Report will include: A policy on how to prevent and mitigate major accidents; A management system for implementing that policy; An effective method for identifying any major accidents that may occur; Measures (such as safe plant and safe operating procedures) to prevent and mitigate major accidents; Information on the safety precautions built into the plant and equipment when it was designed and constructed; Details of measures (such as fire-fighting, relief systems and filters) to limit the consequences of any major accident that might occur; and Information about the emergency plan for the site, which can also be used by the local authority in drawing up an off-site emergency plan. Hazard management will identify hazard and consequences, assess and optimize risks and provide tools for managing each risk. There will be hazard reviews including Hazard and Environmental Identification ( HAZID and ENVID ), Project Safety Reviews (PSR s), Hazard and Operability ( HAZOP ), PHSER (Project Health Safety Environmental Review) and other project safety and environmental processes during the project stages. All personnel working at sites will be expected to fully conform at all times to the appropriate ONGC requirements for PPE (Personal Protective Equipment) for the area in which they work Safety rules will be developed and adhered to by all employees and contractors whilst involved in ONGC Ltd. activities. Key areas such as Permit to Work (PTW), energy isolation and hazard identification / risk assessment shall be fundamental to the development of these rules. These rules shall also be in compliance with relevant laws, company policy and established international practices. VIMTA Labs Limited, Hyderabad C9-3

190 Chapter-9 Administrative Aspects Health Systems, equipment and layout should be designed to ergonomic principles to help facilitate both operation and maintenance of the equipment. Health and Safety of all personnel will be a consideration in design to ensure that the risks to those personnel are minimised. This should include a human factor study of the design which will address issues such as exposure to noise, heat, cold, stress, lighting, control room design, control desk VDU layout, field accommodation and recreation facilities, transportation etc. A pre-mobilisation, company approved minimum level of medical fitness including all applicable regional vaccinations will be required for all persons working at the drilling well site. This will apply to all company and contract employees and will continue throughout the life of the project and into the operations phase. An approved exposure monitoring and health surveillance programme will be in place throughout the project phases Environment The exploratory drilling operations will be strictly avoided in sensitive ecological locations within the block area. The EIA will provide guidance on what particular areas should be monitored; these will typically include flaring, chemical consumption, emissions to air, liquid discharges and waste disposal. Waste management will be designed into the facilities to allow and encourage safe and efficient waste reduction, recycling, segregation and disposal. The drilling operation will be designed to first minimise waste and then effectively deal with that waste which is generated. The detailed design needs to ensure waste disposal is consistent with local and or statutory regulations and requirements. Any implications on wildlife need to be understood and any impacts avoided or minimised. 9.3 Environmental Organisation and Personnel To facilitate the implementation of the Environmental Management systems, one of the most important aspects related to are, the organization and personnel. ONGC is committed to extend the EMS to its proposed facilities in Kolasib town, Kolasib District, Mizoram. All individual departments will be accountable for the environment in and around them and individual departments take prompt action in dealing with environmental issues. The HSE dept is the nodal agency to coordinate and provide necessary services on environmental issues during construction and operation of the exploratory drilling project. The department consists of officers from various disciplines to co-ordinate the activities concerned with the management and implementation of the environmental control measures. Basically, this department will supervise the monitoring of environmental pollution levels viz. ambient air quality, water and effluent quality, noise level either departmentally or by appointing external agencies wherever necessary. VIMTA Labs Limited, Hyderabad C9-4

191 Chapter-9 Administrative Aspects In case the monitored results of environmental pollution found to exceed the allowable limits, the Environmental Management Cell will suggest remedial action and get these suggestions implemented through the concerned authorities. The Environmental Management Cell will also co-ordinate all the related activities such as collection of statistics of health of workers and population of the region, afforestation and green belt development. A dedicated HSE set-up in the corporate level will oversee the environmental management and pollution control aspects and headed by Director (Business Services) and constituted by Deputy General Manager (Environment and CSR), Environmental Manager, Environmental Engineers and Social Scientists. The Organizational Structure of Environmental Management is presented in Figure-9.1. This environmental group is responsible for implementation of environmental management plan at asset level, interaction with the environmental regulatory agencies, reviewing draft policy and planning, etc. This department interacts with MoEF&CC, Central Pollution Control Board (CPCB) and other environment regulatory agencies. The department shall also interact with operational and local people to understand their problems and to formulate appropriate plans. VIMTA Labs Limited, Hyderabad C9-5

192 Chapter-9 Administrative Aspects Organizational Setup Environment Basin manager, A & AA basin, Jorhat Head Drilling Services (HDS) I/C HR/ER - CSR I/C HSE, A & AA basin, Jorhat Drilling HSE Engineer HSE Engineer Field Environmental Engineer FIGURE-9.1 ORGANIZATIONAL STRUCTURE FOR ENVIRONMENTAL MANAGEMENT VIMTA Labs Limited, Hyderabad C9-6

193 Chapter-10 Summary and Conclusions 10.0 SUMMARY AND CONCLUSIONS Oil and Natural Gas Corporation Limited (ONGC) proposes to carryout exploratory drilling at 2 wells in on-shore Block AA-ONN-2001/2. The block is located in the NELP Block area of Kolasib & Mamit District, Mizoram. The proposed project activity intends to identify the presence of hydrocarbon prospects through exploratory drilling and to delineate and quantify hydrocarbon pools in discovered fields through exploratory drilling. The proposed project will basically involve drilling of 2 exploratory wells in the block. As per the Environment Impact Assessment (EIA) Notification dated 14 th September, 2006, the proposed exploratory drilling project falls under Category A of Activity Type 1(b) Location Details of the Project The block under study falls in district of Kolasib and Mamit, Mizoram. The Block area lies between latitude & and longitude & The area has undulating terrain, dense jungles and is almost devoid of approach roads. The 2 well coordinates are given below: Sr. Proposed Well No. Location Latitude Longitude 1 HOAC HOAD Importance of the Proposed Project India is not among the major producers of crude oil, as it doesn t have much oil reserves. Therefore, India generally 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 the state can boost the state s economic development to a great extent. The proposed exploration project is thus of immense significance for the state Details of Exploration Drilling Operation It is proposed to drill exploratory and appraisal wells in the delineated area selected through seismic survey to identify and establish hydrocarbon potential. 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 well site is dependent on the type of drilling equipment deployed which in turn is dictated by the planned depth of drilling. VIMTA Labs Limited, Hyderabad C10-1

194 Chapter-10 Summary and Conclusions Infrastructure Requirement Land Requirement: Minimum land required at each well site during drilling will be 125 m x 125 m, i.e., 1.56 ha (2.5 ha will be acquired). On an average, the land requirement at each well site, including site facilities and camp site is considered as ha. The land will be acquired on a temporary basis and adequate compensation as per the guidelines of local administration will be provided. Power Requirement: The total power requirement at the drilling site will be 2250 KVA. The power requirement in the drilling site will be catered through Diesel Generator (DG) sets. The power requirement will be met by 3 Nos of 750 KVA DG sets at drilling site. Stand by DG set arrangement of 750 KVA at drilling site will be made. Water Requirement: Water is basically required for preparing drilling mud and for meeting domestic needs of the campsite. Typically, the water consumption for each well ranges from 25 m 3 /day for a short period of 4 5 months. However, the drilling and domestic water requirement would depend on the time required to drill the well, which is primarily dependent on the proposed depth. Man Power: The drill site construction would be done largely employing local labour. At each drill site construction, local employment will be generated for about 25 person/shift of 12 hrs in two shifts Baseline Environmental Status Environmental monitoring has been carried out in 10-km radius around the proposed wells covering partly winter and partly pre-monsoon season of the year Land Use Studies The land use pattern has been studied by District Census Hand Books and satellite images. It is observed that 4.6 % of the land falls under crop land. On the other hand, 80.1 % of land falls under wastelands area. The water bodies contribute about 10.4 % area falls under Reservoir/River etc Soil Quality The soil samples were tested at 10 locations during winter season covering various land uses. It has been observed that the ph of the soil ranged from indicating that is slightly alkaline to moderately alkaline in nature. The electrical conductivity was recorded as µs/cm to µs/cm. The organic carbon content in the study area observed as 0.53 % to 1.02 %, which the soil falls under average sufficient to more than sufficient. The potassium values ranged between 86.6 to kg/ha. The phosphorus values ranged between 13.5 to 88.6 kg/ha. The nitrogen values ranged between kg/ha 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 VIMTA Labs Limited, Hyderabad C10-2

195 Chapter-10 Summary and Conclusions meteorological data generated by nearest India Meteorological Department (IMD) stations located at Agartala. The meteorological data generated at the monitoring site when compared with the data recorded at nearest IMD station, it is observed that the data generated at the site is broadly in comparison with regional meteorology, except for minor variations Ambient Air Quality To establish the baseline status of the ambient air quality in the study area, the air quality was monitored at 10 locations during partly winter and partly premonsoon season of Out of the ten locations the minimum and maximum concentration for PM10 were varied between 37.7 to 46.0 g/m which are well within the NAAQ standard i.e 100 g/m 3. The minimum and maximum concentration PM2.5 were varied between 11.6 to 15.8 g/m 3 respectively during the study period which are well within the NAAQ standard i.e 60 g/m 3. The concentrations of SO2 were varied between 7.9 to 15.0 g/m 3 which are well within the NAAQ standard i.e 80 g/m 3. The concentrations of NOx were varied between 11.0 to 17.3 g/m 3 respectively which are well within the NAAQ standard i.e 80 g/m 3. The minimum and maximum concentration for CO during the study period was observed as 100 to 239 g/m 3 which are well within the NAAQ standard i.e 2000 g/m 3. The minimum and maximum concentration for total hydrocarbons, methane hydrocarbons and non-methane hydrocarbons during the study period were observed as 101 to 166 g/m 3, 50 to 95 g/m 3 and 40 to 96 g/m 3 respectively. The concentration of VOCs is observed in the range of ppm. 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 Water Quality The baseline water quality status in the region is established by analyzing about 4 surface water samples and 6 ground water samples during study period. The physico-chemical and biological analysis revealed that most of the parameters in ground water samples are well within the permissible limits when there is no alternative choice as per IS: The physico-chemical and biological analysis revealed that all the parameters in surface water samples are well within the prescribed limits of IS: limits Ambient Noise Levels The noise monitoring has been conducted at 10 locations, covering residential, commercial and silence zones in the study area. A review of this data indicates that at all the locations, the noise level was found within the permissible limits of CPCB. VIMTA Labs Limited, Hyderabad C10-3

196 Chapter-10 Summary and Conclusions Ecological Environment An ecological survey in the study area was conducted particularly with reference to the listing of species and assessment of the existing baseline ecological (Terrestrial and Aquatic ecosystem) conditions in the study area. No reserved forest and national park present in 10-km radius of proposed well locations. The nearest wildlife Sanctuary, Dampa Tiger Reserve is located at about distance of 75.3 Km/SSW direction from HOAD well site Socio-Economic Environment The configuration of male and female indicates that the males constitute about 49.86% and females to 50.14% of the total population as per 2011 census records. The study area on an average has 1006 females per 1000 males. In the study area, as per 2011 census, 0.17% of the population belongs to Scheduled Castes (SC) and 91.54% to Scheduled Tribes (ST). The percentage of male literates to the total literates of the study area works out to be 50.13%. The percentage of female literates to the total literates, which is an important indicator for social change, is observed to be 49.87% in the study area as per 2011 census records. Total work participation in the project study areas is 41.78% and the non-workers constitute 58.22% of the total population respectively Impact Assessment The identification and assessment of impacts over the various environmental attributes in the region due to the proposed exploratory drilling activities in the proposed AA-ONN-2001/2 block are discussed and mitigative measures and environmental management plan for the potential impacts have also been presented. The duration of construction works including site excavation, preparation and well pad construction is expected to last approximately 4-5 months for each well site Impact on Topography and Land Use Drilling exploratory well is a short duration activity at each drilling location, typically encompassing a period of 4 to 5 months from land acquisition to site abandonment. The impact would therefore be localised, 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 Impact on Climate Impact on the climatic conditions from the drilling will not be significant. The maximum temperatures of the exit gas from the DG stack and flare stack will be around 300 C and 400 C respectively. In terms of total emission of green house gases and consequent impact on global warming or on potential for local increase VIMTA Labs Limited, Hyderabad C10-4

197 Chapter-10 Summary and Conclusions 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 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 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 will be mobilized by wind, and deteriorate the ambient air conditions. 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 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 Impact on Surface Water and Groundwater Quality Approximately m 3 /day of wastewater and 4 m 3 /day of sewage would be generated from each well site. Water based non-toxic biodegradable fluids with inhibitive and encapsulative characteristics are proposed to be used as drilling mud for minimizing any long term impact on groundwater quality. Additionally, the drilling mud collection and recirculation pond is lined with impervious layer to prevent seepage and loss of drilling fluid into the subsoil. Further, proper casing installation and cementing of well will ensure least groundwater contact. The clarified wastewater will be treated in packaged treatment plant located at the well sites to meet norms specified by CPCB and MPCB. The sewage will be discharged into septic tanks and then to subsoil through soak pits Impact on Noise Levels During the drilling 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. The maximum predicted noise level at about 100 m from the boundary of the drill site is about 52.0 db (A). The ambient noise levels at most of the places in the region are within the CPCB standards. Since, the drilling operations last for only 3 to 4 months at each location, impact of the noise pollution due to the proposed exploratory drilling will be insignificant on the community Ecological Impacts Impact on the ecology of the study area will vary with the proximity of the habitats from the drilling locations. However, the impacts are of temporary VIMTA Labs Limited, Hyderabad C10-5

198 Chapter-10 Summary and Conclusions nature, which will last only for few months at each drill location during the exploratory drilling activities and will thus allow subsequent recovery after the activities stops 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 drilling activity has been assessed to be minimal. In addition employees working at the drill site would be provided protective devices like ear plugs/ear muffs for ensuring minimum impact on human health. For most potential drilling sites in the Exploration Area, it 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 exploration drilling programme is expected to generate local employment in the order of about 25/shift 12 hrs. Unskilled and semi-skilled people, for a period of approximately 3 to 4 months at each drilling site location. While this benefit is small by most standards, it is a significant employment opportunity in the block Environment Management Plan 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, but all other equipment and materials will be removed from the site. All empty drums, wastes, used and unused drilling fluids, fuel and lubricants will be removed from the drilling site. Water supply and effluent discharge hoses and associated equipment will be removed. The access road(s) would be reinstated Decommissioning upon Abandonment In the event that no economic quantities of hydrocarbons are found, a full abandonment plan will be implemented for the drilling sites in accordance with the applicable Indian petroleum regulations Atmospheric Emissions The combustion of diesel for power generation for the drilling and campsite operation results in atmospheric emissions of SO2, NOx, CO, Particulates and Hydrocarbons. Flaring during production testing is of days duration and atmospheric emissions are marginal. VIMTA Labs Limited, Hyderabad C10-6

199 Chapter-10 Summary and Conclusions There will be no sensitive receptors to the emissions of combustion products in the vicinity of the proposed drilling operations apart from the crew of the drilling rig. The impacts caused are therefore, considered to be negligible. Measures to ensure minimal impacts include appropriate management of 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 Noise Environment The modeling results show that the noise levels will attenuate to below permissible levels within the drilling site boundary. The Generators will be properly enclosed and the exhausts will be provided with silencers Management of Drilling Wastes The major waste product of a drilling operation is the generation of rock cuttings with residual mud adhering to the drill cuttings and spent drilling fluid. About m 3 of drill cuttings per well and 15 m 3 spent drilling fluid would need to be disposed off. ONGC proposes to use internationally followed methodologies while drilling either with Water Based Muds (WBM). The volume of drilling fluids used will be optimizing at the design stage by selecting modern drilling engineering technology. The mud will be reused after its separation from the cuttings. A mud mixing tank will be set up at the drilling site with a collection system so that any spill of chemicals will be collected. The platform all around the tank on the pedestrial shall be of metal gratings to facilitate walkway as well as to permit the fluid to pass through so that it can be collected in the collection for further reuse / disposal. The spilled oil may be reused in the mud preparation. At the extent possible reuse the residual drilling fluids in the drilling campaign only the drilling fluid which is not further used can be discarded Management of the Solid Wastes Small amounts of solid wastes will be generated during normal operation at the drilling rig. The wastes will be disposed on compliance with local and national legislations. Spent waste oil to be stored in a secure paved area and disposed to MoEF/ MPCB approved waste oil recyclers. Drill cuttings and sludge from drilling mud to be buried within the impervious lined pit and covered with soil as part of the site abandonment plan. Biodegradable waste arising from kitchen and canteen activities to be scientifically composted and the bio-manure so generated to be used for green belt development. VIMTA Labs Limited, Hyderabad C10-7

200 Chapter-10 Summary and Conclusions Management of Waste Disposal sites within Drill Site The project proponent will dispose the drill cuttings, drill mud and wastewater generated during the drilling operations into the lined pits of various sizes and undertaking plantation within the drill site particularly on the reclaimed pits Environmental Monitoring Program A detailed post project monitoring in respect of air, water, soil, landuse, occupational noise, etc. to assess the changes has been evolved covering various phases of project advancement. A network of sampling locations around the operational facilities will be established. The monitoring shall include the compliances to legal and statutory controls imposed on the operation as well as other corporate commitment to responsible environment management. Systems for monitoring resources inputs (energy, chemical use, water, raw materials), equipment and plant performance and waste generations will also be set up. A detailed wastes management plan with monitoring programme will be in place during various phases of activity Risk Assessment and Disaster Management Plan The hazard potential of oil and gas and estimation of consequences in case of their accidental release during drilling has been identified and risk assessment has been carried out to quantify the extent of damage and suggest recommendations for safety improvement for the proposed facilities. Risk mitigation measures based on MCA analysis and engineering judgments are incorporated in order to improve overall system safety and mitigate the effects of major accidents. An effective Disaster Management Plan (DMP) to mitigate the risks involved has been prepared. This plan defines the responsibilities and resources available to respond to the different types of emergencies envisaged. Training exercises will be held to ensure that all personnel are familiar with their responsibilities and that communication links are functioning effectively Project Benefits The proposed exploration program will establish hydrocarbons in the block. The development of the oil field will result in considerable growth of service sector and will also generate new industrial and business opportunities in the area. Small and medium scale industries may be developed as consequence. 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. The commercial development will also lead to investment in Mizoram, bringing oil and gas revenues both to the State and to the Central Government. The presence of ONGC in the region will substantially improves the socio-economic conditions of the region. In Operation phase ONGC require significant work force of non-technical and technical persons. Migration of persons with better education and professional VIMTA Labs Limited, Hyderabad C10-8

201 Chapter-10 Summary and Conclusions experience will result in increase of population and literacy in the surrounding villages Administrative Aspects The basis of the operational philosophy is that the activities proposed in oil and gas processing shall be operated in complete compliance with all applicable Laws, Regulations, Standards and Permits, the Production Sharing Contract (PSC), ONGC corporate policies, procedures, specifications, rules, standards and guidelines. In order to achieve this, the proposed drilling sites will be maintained by technically qualified and experienced people. Detailed procedures and plans will be developed for each activity prior to operations start up. All persons on board the drilling rig will be an experienced crew with valid qualifications. ONGC has a well defined Organization for Environment Management System. ONGC is committed to extend the EMS to its proposed facilities in Mizoram. The Director (Operations) of the project oversees the total environmental activity on a day-to-day basis. All individual departments are accountable for the environment in and around them and individual departments take prompt action in dealing with environmental issues. The HSE dept is the nodal agency to coordinate and provide necessary services on environmental issues during construction and operation of the project Conclusions The proposed exploratory drilling 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 With the effective implementation of the Environment Management Plan (EMP) during the planning, design, construction and operation phases, the development and production project can proceed without significant negative impact on the environment. VIMTA Labs Limited, Hyderabad C10-9

202 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-11 Disclosure of Consultants 11.0 DISCLOSURE OF CONSULTANTS 11.1 Introduction The Environmental Impact Assessment (EIA) and Environment Management Plan (EMP) report has been prepared by carrying out various scientific studies. Studies have been carried out by engaging scientists/engineers/experts of Vimta Labs Limited, India and its associates Vimta Labs Limited - Environment Consultant Vimta Labs Limited is a leading multi-disciplinary testing and research laboratory in India. VIMTA provides contract research and testing services in the areas of environmental assessment, analytical testing, clinical research, preclinical (animal) studies, clinical reference lab services, advanced molecular biology services and research & development studies. The Environment Division has been in the forefront of its vision to provide better environment through guiding and assisting the industry for sustainable development. A stalwart in the mission to protect and preserve the natural resources on earth for future generations, it offers extensive research and consultancy services in the field of environment. With its rich experience, multidisciplinary expertise and with the support of its state-of the-art analytical equipment, the services offered by the division are wide ranging and encompasses entire gamut of environment management and monitoring services. With its emphasis on quality services over the years, it has evolved itself into a single reference point in India for comprehensive environmental services The Quality Policy VIMTA is committed to good professional practices and quality of operations in its testing, validation and research services; VIMTA shall ensure customer satisfaction by maintaining independence, impartiality and integrity in its operations; VIMTA shall provide the services in accordance with national and international norms; VIMTA shall implement quality systems as per ISO/IEC and applicable Good Laboratory Practices (GLPs) & Good Clinical Practices (GCPs), to generate technically valid results/data; and VIMTA shall ensure that all its personnel familiarize with the policies and procedures of the quality system and implement the same in their work Major Milestones and Accreditations Registered with an initial investment of Rs.200,000= Recognized by ISI (now known as Bureau of Indian Standards) VIMTA Labs Limited, Hyderabad C11-1

203 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-11 Disclosure of Consultants Qualified by the criteria of Ministry of Environment and Forests, India and was notified as one of the first 14 Standard Environmental Laboratories published in the Gazette of India Licensed for carrying out tests on Drugs and Pharmaceuticals Accredited by NCTCF, DST, Government of India (the forerunner of NABL) Accredited by NABL, India under its revised scheme, certified by Standards Australia, Quality Assurance Services as per ISO/IEC Guide 25 and ISO GLP Compliance Accreditation by GOSSTANDART and joint venture for certification of Food Exports with ROSTEST, Russia World Bank Recognition ANVISA Brazil Certification USFDA accepts Vimta Bioequivalence study report. Showcased Vimta at AAPS (USA) and ICSE-CPHI (Germany) 2003 Recognized by Saudi Arabian Standards Organization Enters Gulf market - Executes a contract for environmental consultancy in Kuwait 2006 Expands its overseas activities. Undertakes environmental assignment in Saudi Arabia 2006 Undertakes environmental impact assignment in Tanzania, Africa 2008 Has been Pre-Qualified by World Health Organization (WHO) 2009 Undertaken environment impact Assignment in Cameroon, Africa Services Offered Spread over 70,000 sq.ft lush green garden premises at Cherlapally, Hyderabad (India), the scientifically designed and meticulously groomed infrastructural facility of the Central Laboratory of VIMTA has the most sophisticated instruments backed by an excellent team of professionals. Over 150,000 sq. ft. of world class research laboratory is also under operation at Biotech Park-Genome Valley, Hyderabad (India). Having all the facilities under one roof is perhaps the only one of its kind in South Asia in the contract testing and research sector. VIMTA Labs Limited, Hyderabad C11-2

204 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-11 Disclosure of Consultants VIMTA Central Laboratory, Cherlapally, Hyderabad VIMTA Life Sciences, Genome Valley, Hyderabad Vimta offers services under the following specializations: Environment; Analytical; Clinical Reference Lab; Clinical Research; Preclinical; Molecular Biology; and Research and Development. The environment division of VIMTA Labs Limited (VLL) has its presence all over India and other countries including a strong association with international consultants like Japan Bank for International Cooperation (JBIC), Kennametal Inc. - USA, Rudal Blanchard UK, E&E Solutions Japan, NAPESCO & Kuwait National Petroleum Corporation Kuwait, Marafiq and Haif Consultants Saudi Arabia and others. Vimta Labs Limited has the following credentials: Recognition by BIS, India; Recognition by Ministry of Environment and Forests, Govt. of India and various State Pollution Control Boards (wherever applicable); Recognition by Department of Science & Technology, Govt. of India (NABL); Recognition by Ministry of Defence, Govt. of India; Recognition by APEDA, Ministry of Commerce, Govt. of India; Recognition by Saudi Arabia Standard Organization (SASO), Saudi Arabia; Recognition from NEMC, Tanzania; Accreditation by NCTCF; Certification from Standard Australia; Recognition from ANVISA Brazil; Recognition from USFDA; Quality Assurance Services as per ISO/IEC 17025; Quality Assurance Services as per ICH Guidelines; and Recognition by World Health Organization (WHO) Services of Environment Division Environment essentially being a multi-disciplinary science, the range of services offered by the division are also comprehensive and caters to the needs of VIMTA Labs Limited, Hyderabad C11-3

205 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-11 Disclosure of Consultants industry, pollution control agencies, regulatory authorities and in a larger pursuit of a green globe. The services under environment include: Site selection and liability studies; Environmental impact assessments; Environment management plans; Carrying capacity based regional studies; Environmental audits; Solid and hazardous waste management; Risk assessment (MCA,HAZON,HAZOP) & disaster management plans; Occupational health and safety, industrial hygiene; Environmental monitoring for air, meteorology, water, soil, noise, ecology and socio-economics; Industrial emission source monitoring; Offshore sampling and analysis of marine water and sediments; Marine ecological studies; Marine impact assessment; Rehabilitation and resettlement studies; Forestry and ecological studies; Geological and hydro-geological studies; Land use /land cover studies based on remote sensing; Socio-economic studies; Due diligence studies; Industrial epidemiological studies; Wasteland management studies; and Study on bio-indicators. The services under Environmental Chemistry include: Analysis of water, wastewater, soil, solid waste, hazardous waste as per international codes; Source emissions and work zone air/noise quality monitoring; Analysis of SVOCs, VOCs, PAH, BTEX, AOX, PCB s, TCLP metals, TOC etc.; Categorization of hazardous waste; and Pesticide residue analysis Facilities of Environment Division Vimta-Environment Division is located in scientifically designed Central Laboratory with the state-of the-art modern facilities to offer vide range of services in indoor and outdoor monitoring and analytical characterization in the field of Environment. Further, it is ably supported by highly skilled and experienced team of professionals in the fields of science, engineering, ecology, meteorology, social planning, geology & hydro-geology and environmental planning. Besides the regular monitoring equipment such as PM10 & PM2.5 Samplers, automatic weather monitoring stations, stack monitoring kits, personal samplers, noise meters, portable water kits etc, the other major specialized equipment include: VIMTA Labs Limited, Hyderabad C11-4

206 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-11 Disclosure of Consultants Monostatic Sodar Designed by National Physical Laboratory, GOI; Integrated Noise Level Meters Quest, U.S.A; Flue Gas Analyzers Testo, Germany; 113-A Gravimetric Dust Sampler-Casella, London; ICP AES Varian, USA; Gas Liquid Chromatographs with FID, ECD & pfpd Varian, USA; Gas Chromatograph with Mass Detector Varian, USA; Atomic Absorption Spectrometer [AAS] Varian, USA; PAS-AFC-123 instrument; High Performance Liquid Chromatograph (HPLC); Laser Particle Size Analyzer; Bomb Calorimeter; Polarographs; X-ray Fluorescent Spectrometer; Flame Photometer; Carbon Sulphur Analyzer; Computerized Fatigue Testing Machine; Electronic Universal Testing Machine; Fourier Transmission Infrared Spectroscope; and Water Flow Current Meter make Lawrence & Mayo. HIGH RESOLUTION GAS CHROMATOGRAPHS VIMTA Labs Limited, Hyderabad C11-5

207 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-11 Disclosure of Consultants Quality Systems The basic fact that environment division and its supporting site laboratories are accredited by NABL (IS ) and Ministry of Environment and Forests, India and by other international bodies stand testimony to its emphasis on Quality Systems. The detail of the persons involved in the preparation of present EIA/EMP report is presented below: VIMTA Labs Limited, Hyderabad C11-6

208 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-11 Disclosure of Consultants DETAILS OF PERSONNEL INVOLVED IN CURRENT EIA/EMP STUDY VIMTA LABS LTD Sr. No. Name Qualification Position Contribution Expertise/Functional Area 1 Mr. M. Janardhan M.Tech Vice President Co-ordination EIA Co-ordinator and (Env. Engg) & Head (Env) FAE for AP, AQ, NV & SHW Experience About 27 years of experience in the field of Environmental Management and Environmental Engineering 2 Dr. B. Chandra Sekhar M.Sc., Ph.D Sr. Manager Co-ordination EIA Co-ordinator About 18 years of experience in the field of Environmental Management and Modeling 3 Mr. G. V. Raghava Rao M.Tech (Env) Manager Expert FAE-AP, ISW & MSW About 14 years of experience in the field of Environmental Management and Environmental Engineering 4 Ms. Durga Bhavani M. Sc (Env Science), M.Tech Group Leader Expert FAE WP, AQ, Team Member SHW About 13 years of experience in the field of Environmental Management and Environmental Chemistry 5 Mr. S. Kishore Kumar M.Tech (Env) Group Leader Expert FAE AP, NV About 5 years of experience in the field of Environment Management and Engineering 6 Mr. M. Raja Manohar M.Tech (Env ) Env Engineer Expert Team Member About 5 years of experience in the field of Environment Management and Engineering 7 Mr. Rajashekar T M.Sc., Ph.D Sr. Scientist Expert FAE-EB About 10 years of experience in the field of Terrestrial and Aquatic Ecology 8 Mr. S. Srinivas Goud M.S.W Group Leader Expert FAE-SE About 12 years of experience in the field of social Impact Assessment Studies 9 Mr. Ramakrishna Pullipaka M.Tech Env Engineer Expert Team Member About 4 years of experience in the field of Environment Management and Engineering 10 Mr. M. Praveen Kumar M.E Env Engineer Expert Team Member About 2 year experience in the field of Environment Management and Engineering 11 Mr. J. Sunil Kumar M.Tech Env Engineer Expert Team Member About 2 year experience in the field of Environment Management and Engineering 12 Mr. Sanjay Chavan M.Sc (Env) Env Scientist Expert Team Member About 3 years of experience in the field of Environmental monitoring and management 13 Mr. K.S.Vishnu Teja M.Tech Env. Engineer Expert Team Member About 3 year experience in the field of Environment Management and Engineering 14 Mr. Ch. Narendra M.S.W Scientist Expert AFAE-SE About 5 years of experience in the field of Social Impact Assessment Studies 15 Mr. Rajeshwar MSc. Geology & Hydrogeology Scientist Trainee Team Member Team Member-HG About 5 years of experience in the field of geology and Hydrogeology VIMTA Labs Limited, Hyderabad C11-7

209 wells in Existing NELP Block AA-ONN-2001/2, Kolasib & Mamit District, Mizoram Chapter-11 Disclosure of Consultants Sr. No. Name Qualification Position Contribution Expertise/Functional Experience Area 16 Mr. P. Niranjan Babu B.Com Dy. Manager Secretarial Support -- About 25 years of experience in the field of environmental monitoring and secretarial support 17 Mr. P. Krishna I.T.I (Civil) Jr.Engineer Cartography -- About 15 years of experience in the field of environmental management and civil drawings 18 Mr. J. Rama Krishna I.T.I (Civil) Jr.Engineer Cartography -- About 14 years of experience in the field of environmental management and civil drawings Empanelled Experts 1 Dr. Y. Rama Mohan Rao M.Sc. Consultant Expert FAE-HG, LU/LC About 15 years of experience in the field of Land use studies, Remote Sensing and Hydrogeology 2 Mr. Rajgopal Krishnan M. Tech (Chemical Engg) 3 Mr. Balakrishna Shankarrao Lole Consultant Expert FAE for RH About 40 years of experience in the field of Risk and Hazard assessment M.Sc. (Ag) Consultant Expert FAE for SE About 38 years of experience in the field of Soil Conservation VIMTA Labs Limited, Hyderabad C11-8

210 ANNEXURE-I TERMS OF REFERENCE LETTER AND COMPLIANCE AI-1

211 ANNEXURE-I TERMS OF REFERENCE LETTER AND COMPLIANCE AI-2

212 ANNEXURE-I TERMS OF REFERENCE LETTER AND COMPLIANCE AI-3

213 ANNEXURE-I TERMS OF REFERENCE LETTER AND COMPLIANCE AI-4

214 ANNEXURE-I TERMS OF REFERENCE LETTER AND COMPLIANCE Sr. Particulars of Report Reference No Recommendations in TOR 1 Executive summary of the project Executive Summary has been given in EIA report. 2 Project Description, Project Objectives and Project Benefits. Project description and objectives are given in Chapter-2 and benefits of the project are given in Chapter-8. 3 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. 4 Details of forest land involved in the proposed project. A copy of forest clearance letter, if applicable 5 Details of National Park/Wild life Sanctuary/Reserve Forest/Eco sensitive area within 10 km distance. 6 Permission from the State Forest Department regarding the impact of the proposed plant on the surrounding National Park/Wild life Sanctuary/Reserve Forest/Eco sensitive area, if any. Approval obtained from the State / Central Government under Forest (Conservation Act, 1980 for the forestland should be submitted 7 Distance from nearby critically/severely polluted area as per Notification dated 13 th January, 2010, if applicable. 8 Does proposal involves rehabilitation and resettlement? If yes, details thereof. The site details within 1 km of the proposed wells have been given in Table-1.3, 1.4 and 1. Habitation, an agricultural activities, flora and fauna details have been given in Chpater-3. There is no Wild life sanctuary is situated in the distance of more than 10 km SSW direction from proposed well HOAC, HOAD and BRBAA is shown in Figure-1.2 and Figure-1.3 of Chapter-1 and there is no wildlife national park within 1 km radius of the proposed wells. Satellite image of block area is given in Figure and of Chapter-3. The proposed exploratory drilling well location BRBAA is falling within the forest area, application for forest clearance will be submitted. There is no Wild life sanctuary within 10 km radius. The proposed exploratory drilling well location BRBAA is falling within the forest area, application for forest clearance will be submitted. Nil The land will be taken on temporary lease and will be acquired during development phase only if any prospects are found. If not, the land will be surrendered back to the original land owner in the near original condition. Hence, no R & R is applicable. 9 Details of project cost The estimated cost of the proposed exploration well drilling would be around Rs. 200 Crores. 10 Environmental considerations adopted in the Not Applicable selection of the drilling locations for which environmental clearance is being sought. Any analysis suggested for minimizing the foot print giving details of drilling and development options considered. 11 Baseline data collection for air, water and The baseline studies were carried out from AI-5

215 ANNEXURE-I TERMS OF REFERENCE LETTER AND COMPLIANCE Sr. No Particulars of Recommendations in TOR soil for one season leaving the monsoon season in an area of 10 km radius with centre of Oil Field as its centre covering the area of all proposed drilling wells. It includes; Report Reference 15 th January 2016 to 8 th April 2016 which is representing the winter season. (i) Topography of the project site. Topography of the site is given in Figure-1.2 of Chapter-1. (ii) Ambient Air Quality monitoring at 8 locations for PM 10, SO 2, NOx, VOCs, Methane and non-methane HC. AAQ results are given in Table of Chapter-3. (iii) Soil sample analysis (physical and chemical properties) at the areas located at 5 locations. Soil samples results are given in Table of Chapter-3. (iv) Ground and surface water quality in the vicinity of the proposed wells site. Surface and Ground water samples results and discussion are given in Table and of Chapter-3. (v) Climatology and Meteorology including wind speed, wind direction, temperature rainfall relative humidity etc. Meteorological details are given in Section- 3.5 of Chapter-3, it s includes the site specific details are given in Table (vi) Measurement of Noise levels (day and night both) within 1 km radius of the proposed wells. Noise level survey results and discussion are given in Table of Chapter-3. (vii) Vegetation and land use; Animal resources 12 Incremental GLC as a result of DG set operation. 13 Potential environmental impact envisages during various stages of project activities such as site activation, development, operation/ maintenance and decommissioning. 14 Actual source of water and Permission for the drawl of water from the Competent Authority. Detailed water balance, wastewater generation, recycling and its final discharge. 15 Noise control and measures to minimize disturbance due to light and visual intrusions in case coastally located areas. Ecological studies were carried out during the study period about flora and fauna is given in Chapter-3. The incremental concentration of gaseous emission are given in Table-4.4 of Chapter-4. Impact assessment and mitigation measures for the stage wise proposed project activities are given in Chapter-4 of the EIA report. At present water is sourced from local tankers/ tube well. Detailed water balance, wastewater generation, recycling and its final discharge is given in Section and of Chapter-2. Noise control measures are given in Section of Chapter-4 AI-6

216 ANNEXURE-I TERMS OF REFERENCE LETTER AND COMPLIANCE Sr. Particulars of Report Reference No Recommendations in TOR 16 Treatment and disposal of wastewater Wastewater treatment and disposal details are given in Section of Chapter Treatment and disposal of solid waste generation. Details of wastewater process is given in Section of Chapter-4. Solid waste management details are given in Section of Chapter-4. Classification and disposal and waste details are given in Section-4.6 of Chapter Disposal of spent oil and lubes. Mangement of used oil details are given in Sections and Section of Chapter Storage of chemicals and diesel at site. Details for storage of chemicals are given in Section of Chapter Commitment for the use of WBM only Water Based Mud (WBM) waste from drilling details are given in Section of Chapter Mud make up and mud and cutting disposal all options considered should be listed with selective option. 22 Hazardous material usage, generation, storage accounting and disposal. Drilling mud and it s cutting details are given in Section and of Chapter-2. Hazardous waste details are given in of Chapter Disposal of packaging waste from site. Packaging waste disposal details are given in Section of Chpater Oil spill emergency plans in respect of recovery/ reclamation. Oil spill emergency plan is given in Section of Chapter H 2S emissions control. H 2S emission control details are given in Section of Chpater-7. Fugitive emissions are given in Chapter-4 26 Produced oil handling and storage. Not Applicable 27 Details of scheme for oil collection system Not Applicable along with process flow diagram and its capacity. 28 Details of control of air, water and noise pollution in oil collection system. This details are given in Chapter-4 of the EIA report. 29 Disposal of produced/formation water. Disposal of formation water details are given in Section of Chapter Whether any burn pits being utilized for well test operations. Nil 31 Restoration and decommissioning plans which should include mud pits and wastage restoration also and documentation and monitoring of site recovery. 32 Measures to protect ground water and shallow aquifers from contamination along with its monitoring plan. 33 Risk assessment and disaster management plan for independent reviews of welldesigned construction etc. for prevention of blow out. Details of mud pits are given in Section of Chapter-2. Restoration of wastage details are given in Section of Chapter-2 and also given in Section-4.7 of Chapter-4. Pollution control measures for ground water are given in Section of Chapter-4. Risk and disaster management plan are given in Section-7.1 and 7.3 of Chapter Environmental management plan EMP details are given in Section-4.3 of AI-7

217 ANNEXURE-I TERMS OF REFERENCE LETTER AND COMPLIANCE Sr. No Particulars of Recommendations in TOR 35 Documentary proof of membership of common disposal facilities, if any. 36 Details of environmental and safety related documentation within the company including documentation and proposed occupational health and safety Surveillance Safety Programme for all personnel at site. This should also include monitoring programme for the environmental. 37 Total capital and recurring cost for environmental control measures. 38 A copy of Corporate Environment Policy of the as per the Ministry s O.M. No. J-11013/41/2006-IA.II(I) dated 26 th April, 2011 available on the Ministry s website. 39 Any litigation pending against the project and or any direction/order passed by any court of law against the project. If so details thereof. 40 A tabular chart with index for point-wise compliance of above TORs. Report Reference Chapter-4. Membership of common disposal facilities is under progress This details are covered in Chapter-7 of the EIA report The estimated cost of the proposed exploration well drilling would be around Rs. 100 Crores. The cost for environmental control measures has been included in the total project cost Corporate Environment Policy of ONGC is given in Annexure-XII -Nil- Detailed Terms of Reference (ToR) compliance are given in Annexure-I AI-8

218 ANNEXURE-II (A) EXTENSION OF VALIDITY OF TOR AII(A)-1

219 ANNEXURE-II (B) EXTENSION OF VALIDITY OF TOR AII(B)-1

220 ANNEXURE-III APPLICABLE ENVIRONMENTAL STANDARDS 1.0 Ambient Air Quality Standards National Ambient Air Quality Standards for ambient air has been prescribed by the Environment (Protection) Seventh Amendment Rules, 2009 dated 16 th November The prescribed Standards are given below in Table-1. Sr. No. TABLE-1 NATIONAL AMBIENT AIR QUALITY STANDARDS Pollutant Time Weighted Average Industrial, Residential, Rural and other Area Concentration in Ambient Air Ecologically Sensitive Area (notified by Central Government) Methods of Measurement (1) (2) (3) (4) (5) (6) 1 Sulphur dioxide Annual* Improved West and (SO2), µg/m 3 24 Hours** Gaeke -ultraviolet fluorescence 2 Nitrogen Dioxide Annual* Modified Jacob & (NO2), µg/m 3 24 Hours** Hochheiser (Na- Arsenite) -Chemiluminesence 3 Particulate Matter Annual* Gravitmetric (Size less than 10µm) or PM10 µg/m 3 24 Hours** TOEM -Beta attenuation 4 Particulate Matter (Size less than 2.5µm) or PM2.5 µg/m 3 Annual* Gravitmetric 24 Hours** TOEM -Beta attenuation 5 Ozone (O3) µg/m 3 8 hours ** UV photometric 1 hour ** Chemiluminiscence -Chemical Method 6 Lead (Pb) µg/m 3 Annual* AAS /ICP method 24 Hours** after sampling on EPM 2000 or equivalent filter paper -ED-XRF using Teflon filter 7 Carbon monoxide 8 Hours Non Dispersive Infra (CO) mg/m 3 1 Hour** Red (NDIR) 8 Ammonia (NH3) Annual* Chemiluminiscence µg/m 3 24 Hours** Indophenol blue method 9 Benzene (C6H6) µg/m 3 Annual* Gas chromatography based continuous analyzer -Adsorption and Desorption followed by GC analysis 10 Benzo() Pyrene Annual* Solvent extraction (BaP)- particulate phase only ng/m 3 followed by HPLC/GC analysis 11 Arsenic (As) ng/m 3 Annual* AAS /ICP method after sampling on EPM 2000 or equivalent filter paper AIII-1

221 Sr. No. ANNEXURE-III APPLICABLE ENVIRONMENTAL STANDARDS Pollutant Time Weighted Average Industrial, Residential, Rural and other Area Concentration in Ambient Air Ecologically Sensitive Area (notified by Central Government) Methods of Measurement 12 Nickel (Ni) ng/m 3 Annual* AAS /ICP method after sampling on EPM 2000 or equivalent filter paper Note: * Annual arithmetic mean of minimum 104 measurements in a year taken twice a week 24 hourly at uniform intervals. ** 24 hourly or 8 hourly or, 01 hourly monitored values, as applicable, shall be complied with 98% of the time in a year. 2% of the time, the may exceed the limits but not on two consecutive days of monitoring. 2.0 Noise Limits and Guidelines for Diesel Generators Noise from DG set shall be controlled by providing an acoustic enclosure or by treating the room acoustically, at the users end; The acoustic enclosure or acoustic treatment of the room shall be designed for minimum 25 db (A) insertion loss or for meeting the ambient noise standards, whichever is on the higher side (if the actual ambient noise is on the higher side, it may not be possible to check the performance of the acoustic enclosure/acoustic treatment. Under such circumstances the performance may be checked for noise reduction upto actual ambient noise level, preferably, in the nighttime). The measurement for Insertion Loss may be done at different points at 0.5 m from the acoustic enclosure/room, and then averaged; These limits shall be regulated by the State Pollution Control Boards and the State Pollution Control Committees; The manufacturer shall offer to the user a standard acoustic enclosure of 25 db (A) insertion loss and also a suitable exhaust muffler with insertion loss of 25 db (A); The user shall make efforts to bring down the noise levels due to the DG set, outside his premises, within the ambient noise requirements by proper siting and control measures; Installation of a DG set must be strictly in compliance with the recommendations of the DG set manufacturer; and A proper routine and preventive maintenance procedure for the DG set should be set and followed in consultation with the DG set manufacturer which would help prevent noise levels of the DG set from deteriorating with use. 3.0 Ambient Noise Standards Ambient standards with respect to noise have been notified by the Ministry of Environment and Forests vide gazette notification dated 26 th December 1989 (amended in February, 2000). It is based on the A weighted equivalent noise level (Leq). The ambient noise standards are presented in Table-2. AIII-2

222 ANNEXURE-III APPLICABLE ENVIRONMENTAL STANDARDS TABLE-2 AMBIENT NOISE STANDARDS Area Code Category of Area Noise Levels db(a) Leq Day time* Night Time A Industrial Area B Commercial Area C Residential Area D Silence Zone ** Note: * Daytime is from 6 am to 10 pm. ** Silence zone is defined as area up to 100 meters around premises of hospitals, educational institutions and courts. Use of vehicle horns, loud speakers and bursting of crackers are banned in these zones. 4.0 Noise Standards for Occupational Exposure Noise standards in the work environment are specified by Occupational Safety and Health Administration (OSHA-USA) which in-turn are being enforced by Government of India through model rules framed under Factories Act. These are given in Table-3. TABLE-3 STANDARDS FOR OCCUPATIONAL EXPOSURE Total Time of Exposure per Day in Hours Sound Pressure Level in db(a) (Continuous or Short term Exposure) / ¾ 107 ½ 110 ¼ 115 Never >115 Note: 1. No exposure in excess of 115 db(a) is to be permitted. 2. For any period of exposure falling in between any figure and the next higher or lower figure as indicated in column (1), the permissible level is to be determined by extrapolation on a proportionate scale. 5.0 Wastewater Discharge Standards The wastewater discharge standards as per EPA Notification (GSR 176 (E), April 1996) are given in Table-4. TABLE-4 WASTE WATER DISCHARGE STANDARDS Sr. List of Parameters Units Standard Standard No. (On land Irrigation) (Surface Waters) 1 Colour and Odour -- All efforts should be made to All efforts should be made to remove colour and remove colour and unpleasant odour as far as unpleasant odour as far as practicable. practicable. 2 Suspended Solids mg/l Particle size of -- Shall pass 850 micron IS Shall pass 850 micron IS AIII-3

223 ANNEXURE-III APPLICABLE ENVIRONMENTAL STANDARDS Sr. No. List of Parameters Units Standard (On land Irrigation) Standard (Surface Waters) Suspended Solids Sieve Sieve 4 ph value to to Temperature -- Not Specified Shall not exceed 5 o C above the receiving water temperature. 6 Oil and grease, Max. mg/l Total residual mg/l Not Specified 1.0 chlorine, Max. 8 Ammonical nitrogen mg/l Not Specified 50 (as N), Max. 9 Total Kjeldhal mg/l Not Specified 100 nitrogen (as N),Max 10 Free ammonia (as mg/l Not Specified 5 NH3), Max. 11 Biochemical oxygen demand (3 days at mg/l Chemical oxygen mg/l Not Specified 250 demand, Max. 13 Arsenic (as As), Max. mg/l Mercury (as Hg), mg/l Not Specified 0.01 Max. 15 Lead (as Pb), Max. mg/l Not Specified Cadmium (as Cd), mg/l Not Specified 2.0 Max. 17 Hexavalent chromium mg/l Not Specified 0.1 (as Cr +6 ), Max. 18 Total chromium (as mg/l Not Specified 2.0 Cr), Max. 19 Copper (as Cu), Max. mg/l Not Specified Zinc (as Zn), Max. mg/l Not Specified Selenium (as Se), mg/l Not Specified 0.05 Max. 22 Nickel (as Ni), Max. mg/l Not Specified Cyanide (as CN), mg/l Max. 24 Fluorides as F mg/l Not Specified Dissolved phosphates mg/l Not Specified 5.0 (as P),Max 26 Sulphides as (S), mg/l Not Specified 2.0 Max. 27 Phenolic compounds mg/l Not Specified 1.0 (as C2H5OH), 28 Radioactive Materials A] Alpha Emitters, Max. µc/ml B] Beta Emitters, Max. µc/ml Bio-assay test -- 90% survival of fish after 96 hours in 100% effluent. 90% survival of fish after 96 hours in 100% effluent. 30 Manganese (as Mn) mg/l Not Specified Iron (as Fe) mg/l Not Specified Vanadium (as V) mg/l Not Specified Nitrate nitrogen mg/l Not Specified 10.0 AIII-4

224 ANNEXURE-III APPLICABLE ENVIRONMENTAL STANDARDS 6.0 Guidelines for Disposal of Solid Waste, Drill Cutting and Drilling Fluids for Offshore and Onshore Drilling Operation as per Ministry of Environment and Forests vide gazette notification dated 30 th August Disposal of Drill Cutting and Drilling Fluids for On-shore Installations: a) Drill Cuttings (DC) originating from on-shore or locations close to shore line and separated from Water Base Mud (WBM) should be properly washed and unusable drilling fluids (DF) such as WBM, Oil Base Mud (OBM), Synthetic Base Mud (SBM) should be disposed off in a well designed pit lined with impervious liner located off-site or on-site. The disposal pit should be provided additionally with leachate collection system. Design aspects of the impervious waste disposal pit; capping of disposal pit should be informed by the oil industry to State Pollution Control Board (SPCB) at the time of obtaining consent. b) Use of diesel base mud is prohibited. Only WBM should be used for on-shore oil drilling operations. c) In case of any problem due to geological formation for drilling, low toxicity OBM having aromatic content< 1% should be used. If the operators intend to use such OBM to mitigate specific whole problem/ SBM it should be intimated to Ministry of Environment and Forests/State Pollution Control Board. d) The chemical additives used for the preparation of DF should have low toxicity i.e. 96 hr LC50 > 30,000 mg/l as per mysid toxicity or toxicity test conducted on locally available sensitive sea species. The chemicals used (mainly organic constituents) should be biodegradable. e) DC separated from OBM after washing should have oil content at < 10 gm/kg for disposal into disposal pit. f) The waste pit after it is filled up shall be covered with impervious liner, over which, a thick layer of native soil with proper top slope is provided. g) Low toxicity OBM should be made available at installation during drilling operation. h) Drilling wastewater including DC wash water should be collected in the disposal pit evaporated or treated and should comply with the notified standards for onshore disposal. i) Barite used in preparation of DF shall not contain Hg> 1 mg/kg & Cd> 3mg/kg. j) Total material acquired for preparation of drill site must be restored after completion of drilling operation leaving no waste material at site. SPCB should be informed about the restoration work. k) In case, environmentally acceptable methods for disposal of drill waste such as (a) injection to a formation through casing annuals, if conditions allow (b) land farming at suitable location (c) bio-remediation (d) incineration or (e) solidification can be considered, in such cases oil industry is required to submit proposal to Ministry of Environment and Forests/State Pollution Control Board (MoEF/SPCB) for approval. AIII-5

225 1.0 Meteorology ANNEXURE-IV METHODOLOGY FOR SAMPLING AND ANALYSIS The methodology adopted for monitoring surface observations is as per the standard norms laid down by Bureau of Indian Standards (IS:8829) and India Meteorological Department (IMD). 1.1 Methodology of Data Generation The Central Monitoring Station (CMS) equipped with continuous monitoring equipment was installed at site at a height of about 10-m above ground level to record wind speed, direction, relative humidity and temperature. The meteorological monitoring station was located in such a way that it is free from any obstructions and as per the guidelines specified under IS:8829. Cloud cover was recorded by visual observation. Rainfall was monitored by rain gauge. The continuous recording meteorological instrument of Dynalab, Pune (Model No.WDL1002) has been used for recording the met data. The sensitivity of the equipment is as given in Table-1. TABLE-1 SENSITIVITY OF METEOROLOGY MONITORING STATION Sr. No. Sensor Sensitivity 1 Wind speed Sensor ± 0.02 m/s 2 Wind direction Sensor ± 3 degrees 3 Temperature Sensor ± 0.2 o C Hourly maximum, minimum and average values of wind speed, direction and temperature were recorded continuously with continuous monitoring equipment. All the sensors were connected to filter and then logged on to datalogger. The readings were recorded in a memory module, which was attached to datalogger. The memory module was downloaded in computer through Dynalab software. The storage capacity of memory module was 256 KB. Data was downloaded every fortnight into the computer. The data was recorded continuously. The recovery of data was about 98%. The rest of 2 % data gaps were filled by referring to IMD data and daily weather reports in the local newspapers. However, Relative Humidity and Rainfall were recorded manually. 1.2 Ambient Air Quality Method of Analysis The air samples were analyzed as per standard methods specified by Central Pollution Control Board (CPCB), IS: 5184 and American Public Health Association (APHA) Instruments used for Sampling Respirable Dust Samplers APM-451 instruments have been used for monitoring Total Suspended Particulate Matter (TSPM), Respirable fraction (<10 microns) and gaseous pollutants like SO2 and NOx. Charcoal filled glass tubes were deployed for collection of carbon monoxide. Gas Chromatography techniques have been used for AIV-1

226 ANNEXURE-IV METHODOLOGY FOR SAMPLING AND ANALYSIS the estimation of CO. VOC s were collected in specially designed glass tubes called VOC tubes and analyzed on Gas Chromatograph Instruments used for Analysis The make and model of the instruments used at Vimta Labs Limited for analysis of the samples collected during the field monitoring are given in Table-2. TABLE-2 INSTRUMENTS USED FOR ANALYSIS OF SAMPLES Sr. Instrument Name Make Model Parameters No 1 Spectrophotometer HACH DR 2000; Sl. No. SO 2, NOx Electronic Balance Metler AE 200S; Sl. No M10774 TSPM, SPM, RPM 3 Gas Chromatograph With FID, pfpd, ECD GC-3, VARIAN CP ; Sl. No CO, HC, VOC Sampling and Analytical Techniques 1] Particulate Matter PM10, PM2.5, SO2 and NOx PM10 and PM2.5 present in ambient air is drawn through the cyclone. Coarse and non-respirable dust (>10) is separated from the air stream by centrifugal forces acting on the solid particles. These separated particulates fall through the cyclone's conical hopper and collect in the sampling cup placed at the bottom of the cyclone. The fine dust (<10 microns) forming the respirable fraction passes the cyclone and is retained by the filter paper. A tapping is provided on the suction side of the blower to provide suction for sampling air through a set of impingers. Samples of gases are drawn at a flow rate of 0.2 Liters Per Minute (LPM). PM10 and PM2.5 have been estimated by Gravimetric method (IS: 5182, Part IV). Modified West and Gaeke method (IS-5182 Part-II, 1969) has been adopted for estimation of SO2. Jacobs-Hochheiser method (IS-5182 Part-VI, 1975) has been adopted for the estimation of NOx. Calibration: Calibration charts have been prepared for all gaseous pollutants. The calibration is carried out whenever new absorbing solutions are prepared. All the Resirable Dust Samplers are calibrated as per ASTM D The rotameter is calibrated using soap bubble meter. 2] Carbon Monoxide, Hydrocarbon and VOC A sample of the air containing carbon monoxide and hydrocarbons is adsorbed on Charcoal plugged into a glass tube. The adsorbed charcoal is eluted using the solvent, which in turn is projected into the gas chromatograph where it is carried from one end of the column to the other. During its movement, the constituents of the sample undergo distribution at different rates and ultimately get separated AIV-2

227 ANNEXURE-IV METHODOLOGY FOR SAMPLING AND ANALYSIS from one another. The separated constituents emerge from the end of the column one after the other and are detected by suitable means whose response is related to the amount of a specific component leaving the column [CO- IS: 5182 (Part-XVII; HC-IS: 5182 (Part-X)]. VOC s were collected in specially designed glass tubes called VOC tubes and analyzed on Gas Chromatograph. The techniques used for ambient air quality monitoring and minimum detectable level are given in Table-3. TABLE-3 TECHNIQUES USED FOR AMBIENT AIR QUALITY MONITORING Sr. No. Parameter Technique Minimum Detectable Limit (g/m 3 ) 1 PM10 Fine Dust Sampler (Gravimetric 5.0 method) 2 PM2.5 Fine Dust Sampler (Gravimetric 2.0 method) 3 Sulphur dioxide Modified West and Gaeke Oxide of Jacob & Hochheiser 9.0 Nitrogen 5 Carbon Gas Chromatography 12.5 Monoxide 6 VOC s and HC Gas Chromatograph 0.5 to 25 ppb 1.3 Water Analysis 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 glass bottles. Selected physicochemical and bacteriological parameters have been analyzed for projecting the existing water quality status in the study area. Parameters like temperature, Dissolved Oxygen (DO) and ph were analyzed at the time of sample collection. The methodology for sample collection and preservation techniques was followed as per the Standard Operating Procedures (SOP) mentioned in Table-4. TABLE-4 STANDARD OPERATING PROCEDURES (SOP) FOR WATER AND WASTEWATER SAMPLING Parameter Sample Collection Sample Size Storage/ Preservation ph Grab sampling 50 ml On site analysis Plastic /glass container Electrical Conductivity Grab sampling 50 ml On site parameter Plastic /glass container Total suspended solids Grab sampling Plastic /glass container 100 ml Refrigeration, can be stored for 7 days Total Dissolved Solids Grab sampling Plastic /glass container 100 ml Refrigeration, can be stored for 7 days BOD Grab sampling Plastic /glass container 500 ml Refrigeration, 48 hrs Hardness Grab sampling 100 ml Add HNO3 to ph<2, Plastic /glass container refrigeration; 6 months Chlorides Grab sampling 50 ml Not required; 28 days Plastic /glass container Sulphates Grab sampling 100 ml Refrigeration; 28 days Plastic /glass container Sodium, Potassium Plastic container 100 ml Not required; 6 months Nitrates Plastic containers 100 ml Refrigeration; 48 hrs AIV-3

228 ANNEXURE-IV METHODOLOGY FOR SAMPLING AND ANALYSIS Parameter Sample Collection Sample Size Storage/ Preservation Fluorides Plastic containers only 100 ml Not required; 28 days Alkalinity Plastic/ glass containers 100 ml Refrigeration; 14 days Ammonia Plastic/ glass containers 100 ml Add H2SO4 to ph>2, refrigeration, 28 days Hexavalent Chromium, Plastic/ Glass rinse with ml Grab sample; refrigeration; 24 Cr +6 HNO3 hrs Heavy Metals (Hg, Cd, Cr, Cu, Fe, Zn, Pb etc.) Plastic/ Glass rinse with ml Filter, add HNO3 to ph>2; Grab sample; 6 months HNO3 Source: Standard Methods for the Examination of Water and Wastewater, Published By APHA, AWWA, WEF 19 th Edition, Analytical Techniques The analytical techniques used for water and wastewater analysis is given in the Table-5. TABLE-5 ANALYTICAL TECHNIQUES FOR WATER AND WASTEWATER ANALYSIS Parameter Method ph APHA-4500-H + Colour APHA-2120 C Odour IS: 3025, Part-4 Temperature APHA-2550 B Dissolved Oxygen APHA-4500 O BOD APHA-5210 B Electrical conductivity APHA-2510 B Turbidity APHA-2130 B Chlorides APHA-4500 Cl - Fluorides APHA-4500 F - Total dissolved solids APHA-2540 C Total suspended solids APHA-2540 D Total hardness APHA-2340 C Sulphates APHA-4500 SO4-2 Arsenic APHA-3120 B/ APHA-3114 B/ APHA-3500 As Calcium APHA-3120 B/ APHA-3500 Ca Magnesium APHA-3120 B/ APHA-3500 Mg Sodium APHA-3120 B/ APHA-3500 Na Potassium APHA-3120 B/ APHA-3500 K Manganese Mercury Selenium Lead Copper Cadmium Iron Zinc Boron Coliform organisms Alkalinity 1.4 Soil Quality APHA-3120 B/ APHA-3500 Mn APHA-3112 B/ APHA-3500 Hg APHA-3120 B/ APHA-3114 B/ APHA-3500 Se APHA-3120 B/ APHA-3500 Pb APHA-3120 B/ APHA-3500 Cu APHA-3120 B/ APHA-3500 Cd APHA-3120 B/ APHA-3500 Fe APHA-3120 B/ APHA-3500 Zn APHA-4500 B APHA-9215 D APHA-2320 B At each location, soil samples were collected from three different depths viz. 30 cm, 60 cm and 90 cm below the surface and are homogenized. This is in line with IS: 2720 & Methods of Soil Analysis, Part-1, 2 nd edition, 1986 of (American Society for Agronomy and Soil Science Society of America). The homogenized samples were analyzed for physical and chemical characteristics. The soil samples were collected and analyzed once in each season. AIV-4

229 ANNEXURE-IV METHODOLOGY FOR SAMPLING AND ANALYSIS The samples have been analyzed as per the established scientific methods for physico-chemical parameters. The heavy metals have been analyzed by using Atomic Absorption Spectrophotometer and Inductive Coupled Plasma Analyzer. The methodology adopted for each parameter is described in Table-6. TABLE-6 ANALYTICAL TECHNIQUES FOR SOIL ANALYSIS Parameter Method (ASTM number) Grain size distribution Sieve analysis (D ) Textural classification Chart developed by Public Roads Administration Infiltration capacity Infiltrometer Bulk density Sand replacement, core cutter Porosity Void ratio Sodium absorption ratio Flame colourimetric (D ) PH ph meter (D ) Electrical conductivity Conductivity meter (D ) Nitrogen Kjeldahl distillation (D ) Phosphorus Molybdenum blue, colourimetric (D ) Potassium Flame photometric (D ) Copper AAS (D ) Iron AAS (D ) Zinc AAS (D ) Boron Surcumin, colourimetric (D ) Chlorides Argentometric (D Rev 85) Fluorides Fusion followed by distillation and estimation by Ion selective electrod. 1.5 Noise Levels Method of Monitoring Noise level monitoring was carried out continuously for 24-hours with one hour interval starting at 0030 hrs to 0030 hrs next day. The noise levels were monitored on working days only and Saturdays, Sundays and public holidays were not monitored. During each hour Leq were directly computed by the instrument based on the sound pressure levels. Lday (Ld), Lnight (Ln) and Ldn values were computed using corresponding hourly Leq of day and night respectively. Monitoring was carried out at A response and fast mode. Parameters Measured During Monitoring For noise levels measured over a given period of time interval, it is possible to describe important features of noise using statistical quantities. This is calculated using the percent of the time certain noise levels exceeds the time interval. The notation for the statistical quantities of noise levels is described below: Hourly Leq values have been computed by integrating sound level meter. Lday: As per the CPCB guidelines the day time limit is between 07:00 hours to hours as outlined in Ministry of Environment and Forest Notification S.O. 123 (E) dated 14/02/2000. AIV-5

230 ANNEXURE-IV METHODOLOGY FOR SAMPLING AND ANALYSIS Lnight: As per the CPCB guidelines the night time limit is between 22:00 hours to hours as outlined in Ministry of Environment and Forest Notification S.O. 123 (E) dated 14/02/2000. A rating developed by Environmental Protection Agency, (US-EPA) for specification of community noise from all the sources is the Day-Night Sound Level, (Ldn). Ldn: It is similar to a 24 hr equivalent sound level except that during night time period (10 PM to 07 AM) a 10 db (A) weighting penalty is added to the instantaneous sound level before computing the 24 hr average. This nighttime penalty is added to account for the fact that noise during night when people usually sleep is judged as more annoying than the same noise during the daytime. The Ldn for a given location in a community may be calculated from the hourly Leq s, by the following equation. L dn 10Log [ 15 i1 10 ( Leqi /10) 24 9 i1 10 ( Leqi10 /10) ] AIV-6

231 Land Use / Land Cover Study Report Prepared for M/s. ONGC Mizoram Block 3 wells, Mizoram State Submitted by Dr. Y. RAMAMOHAN, Ph.D. QCI-NABET accredited Functional Area Expert (FAE) for Land Use March 2016 Submitted to Environment Division Vimta Labs Limited 142, IDA Cherlapally Hyderabad-Pin Telangana State 1

232 1.0 INTRODUCTION Land Use (LU) refers to man s activities and various uses, which are carried on land. Land Cover (LC) refers to natural vegetation, water bodies, rock / soil, artificial cover and others resulting due to land transformation. Although land use is generally inferred based on the cover, yet both the terms land use and land cover are closely related and interchangeable. Information on the rate and kind of change in the use of land resources is essential to the proper planning, management and regulation of the use of such resources. Knowledge about the existing land use and trends of change is essential if the nation is to tackle the problems associated with the haphazard and uncontrolled growth. A systematic framework is needed for updating the land use and land cover maps that will be timely, relatively inexpensive and appropriate for different needs at both national and state levels. The rapidly developing technology of remote sensing offers an efficient and timely approach to the mapping and collection of basic land use and land cover data over large area. The satellite imageries are potentially more amenable to digital processing because the remote sensor output can be obtained in digital format. Land use data are needed in the analysis of environmental processes and problems that must be understood if living conditions and standards are to be improved from or maintained at current levels. It is required to carry out the land use / land cover study for the project study area (10 km radius) to obtain the necessary environmental clearances from statutory authorities. The objective of the study is to carryout land use / land cover study for the proposed project. The LU / LC study is carried out using the Satellite Imageries (IRS RS2 LISS IV Rabi and Khariff) in addition to Survey of India toposheets. 2

233 Appropriate guidelines are followed while preparing the LU / LC map for the project study area. 2.0 OBJECTIVE The objective of the assignment is to carry out Land use / Land cover study for M/s. ONGC Mizoram Block 3 wells, Mizoram State. 3.0 SCOPE OF THE WORK (STANDARD OPERATION PROCEDURE FOR LAND USE / LAND COVER STUDY) The lu/lc study shall be carried out for a study area of 10 km radius taking site as centre using the satellite imageries (IRS RS2 III / IV 5.8m Resolution) for Rabi / Khariff season. Procurement of latest satellite imagery (IRS RS2 III / IV 5.8m Resolution) based on availability) Rabi or Khariff seasons. Satellite imagery processing and interpretation of land use as per land use classification covering 10 km radius of proposed Project Site. Calculation of land use breakup w. r. t. each land use category covering 10 km of proposed Project Site. Preparation and submission of reports, satellite imageries and maps. PRE-FIELD INTERPRETATION: Collection of Survey of India Topographical maps on 1: 50,000 scale from Survey of India (SOI). Procurement of Satellite Imagery from National Remote Sensing Centre (NRSC) site Geo Co-ordinates from site center taken 10 Km radius. Using ERDAS image processing software processed the raw satellite data. 3

234 Using ARCGIS software converting the all base features from the toposheet, and overlaying the same features on the satellite imagery. Using remote Sensing techniques tone, color, texture and shadow etc. draft land use map is prepared. Before site / ground truthing randomly mark field data checked. With which field work will be carried out. SITE / GROUND TRUTHING: Site visit - capture the Geo-Coordinates of Boundary Pillars and record in field note book. Take traverses and observe the land use categories and map it on the field map on draft map with field photographs. Observe the each land use category like single crop/double crop, industrial area, settlements, forest lands, water bodies, waste lands and etc. The buffer zone area will randomly traverse for correlating mapping units. Collecting secondary data from agricultural department and local people. POST FIELD WORK: Using ARCGIS software plotting the data collected during ground truth maps. Preparation of maps Preparation of report incorporating identification of impacts, quantification of impacts and suggesting mitigative measures in consultation with other FAEs. 4.0 ROLE OF REMOTE SENSING AND GIS Remote sensing and GIS are the modern techniques of terrain analysis and information generation. They not only ensure faster and easier analysis / 4

235 interpretation but also help to modify / manipulate the data at will so as to meet the objective of the study. 4.1 REMOTE SENSING (RS) Remote Sensing (RS) generally involves in processing of remotely sensed data in digital form using image-processing techniques, which created a new and wider dimension in analysis and interpretation. Remote sensing enables one to acquire information about an object or phenomena from a distance through detection or measurement of electromagnetic energy coming from the object. The use of remote sensing techniques for the study of natural resources has been found to be of considerable value. The information derived from the remote sensing is compatible with topographic maps of Survey of India on 1:50,000 or 1:25,000 scale. With the use of high-altitude sensor platform, it is now possible to record extensive areas on a single image, which covers a maximum of 34,000 sq. km (185x185km) and minimum of 3600-sq.km area. Thus one can have a synoptic view over large area and also an integrated picture of the landscape. By using the satellite imagery it is possible to conduct surveys in areas, which are difficult to access. Some of the advantages of utilizing remote sensing techniques are given below: Satellite image serves as a permanent record of a landscape at a point of time from which land use changes can be monitored and evaluated. Satellite data is cost effective when compared to conventional methods. It can be obtained quickly; its information is accurate, reliable and up to date. Preparation of thematic layers by using satellite imagery is time saving when compared to conventional method. 5

236 Satellite data can be effectively integrated with the conventional data for analysis, planning and decision-making. 4.2 GIS Geographic Information System (GIS) is a powerful set of tool, which can perform correlation. GIS is a system for manipulating and analyzing spatial data to provide information to support planning and decision-making. GIS can also be defined as decision support system involving the integration of spatially referenced data in a problem solving environment (Cowen, 1988). It comprises facilities for the input, management, retrieval, manipulation, analysis and display of spatial data. Its functions can be grouped as data acquisition, data utilization, data management, output and display. GIS technology is useful as planning / decision-making tool for resource management. The selective retrieval and analysis capabilities of GIS are used to manipulate the database and provide a variety of information for resource management. GIS is an aid to analyze the thematic maps prepared through remote sensing and field visits. It stores all the maps prepared and database attached to them in digital format, which permits rapid access and processing. Combination of Remote sensing and GIS technologies are very important for assessment and management of natural resources, where integration of data from different sources is an essential requirement. 6

237 5.0 DATA USED The data is used for the preparation of different maps for the study natural resources. The data is used by using the application of Remote Sensing and GIS technologies. Table 1.1 Details of Sources & the Maps Prepared Sl. No. Source Maps Prepared 1. Survey of India s topographic maps and satellite imageries Base map and Drainage map 2. Satellite Imageries Land use / Land cover 6.0 DETAILS OF THE DATA USED Table 1.2 Survey of India s Topographic Maps Sl. No. Topographic Map No. Scale Year of Survey Year of Publication D/7 1: 50, D/8 1: 50, D/11 1: 50, D/12 1: 50, D/15 1: 50, D/16 1: 50, E/1 1: 50, E/5 1: 50, E/9 1: 50, Sl. No. Season Table 1.3 Satellite data of National Remote Sensing Centre Sensor path/row Satellite/Sensor Date of Pass 1. Rabi B IRS RS2 LISS IV 28-February Rabi D IRS RS2 LISS IV 28-February

238 3. Rabi A IRS RS2 LISS IV 16-January Rabi C IRS RS2 LISS IV 16-January PROJECT SITE LOCATION The project site is located at NELP block at Kolasib and Mamit district, Mizoram State. The project site covers an extent of 2992 Sq kilometers. 8.0 STUDY AREA A study area of 10 km radius is delineated taking the proposed project site as centre (Latitude '42.04"N & Longitude '11.20"E). 9.0 LAND USE / LAND COVER MAP Land use / land cover map is prepared by visual interpretation of high-resolution satellite data with the help of Survey of India Topographic maps on 1:50,000 scale. Two seasons data (Rabi year 2015) is used for the delineation of different units. The units are confirmed by the ground truth/field visits. Level-II classification of National (Natural) Resources Information System (NRIS) has been followed for the delineation of units. Land use / Land cover map of the study area is integrated with village map and analyzed with the help of GIS to get the village wise findings of the present land use of the study area, which is given elaborately in the following tables: Land use refers to man s activities and various uses, which are carried on land. Land cover refers to natural vegetation, water bodies, rock/soil, artificial cover and others resulting due to land transformation. Although land use is generally inferred based 8

239 on the cover, yet both the terms land use and land cover are closely related and interchangeable. Information on the rate and kind of change in the use of land resources is essential to the proper planning, management and regulation of the use of such resources. Knowledge about the existing land use and trends of change is essential if the nation is to tackle the problems associated with the haphazard and uncontrolled growth. A systematic framework is needed for updating the land use and land cover maps that will be timely, relatively inexpensive and appropriate for different needs at national and state level. The rapidly developing technology of remote sensing offers an efficient and timely approach to the mapping and collection of basic land use and land cover data over large area. The satellite imageries are potentially more amenable to digital processing because the remote sensor output can be obtained in digital format. Land use data are needed in the analysis of environmental processes and problems that must be understood if living conditions and standards are to be improved or maintained at current levels. Basic Concepts of Land Use Clawson has given nine major ideas or concepts about land. These are: Location or the relation of a specific parcel of land to the poles, the equator, and the major oceans and landmasses. There is also relationship between various tracts of land, as well as a political location. Activity on the land, for what purpose this piece of land or tract is used. Natural qualities of land, including its surface and subsurface characteristics and its vegetative cover. Improvements to and on the land. This is closely related to the activity. 9

240 Intensity of land use or amount of activity per unit area. Land tenure, i.e. who owns the land, which uses it. Land prices, land market activity and credit as applied to land. Interrelations between activities on the land and other economic and social activities. Interrelations in the use between different tracts of land METHODOLOGY FOR LAND USE / LAND COVER MAPPING The land use / land cover map is prepared by adopting the interpretation techniques of the image in conjunction with collateral data such as Survey of India topographical maps and census records. Image classification can be done by using visual interpretation techniques and digital classification using any of the image processing software. For the present study, ERDAS 9.1 version software is used for preprocessing, rectification, enhancements and classifying the satellite data for preparation of land use land cover map for assessing and monitoring the temporal changes in land use land cover and land developmental activities. The imagery is interpreted and ground checked for corrections. The final map is prepared after field check. Flow chart showing the methodology adopted is given in the different land use / land cover categories in the study area has been carried out based on the NRSC land use / land cover classification system. For analysis and interpretation, and preparation of Lu / Lc map, two types of data are needed: 1. Basic data 2. Ground data 10

241 Basic data includes: Fused data of LISS IV Toposheets on 1 : 50,000 Local knowledge Area map on any scale to transfer details Reports and other literature of the study area Ground data: Ground data is very much essential to verify and to increase the accuracy of the interpreted classes and also to minimize the field work. Data analysis: For analysis and interpretation of satellite data, the study can be divided into three parts: A. Preliminary work B. Field work C. Post field work A. Preliminary work includes: To see the limitation of satellite data To lay down the criteria for land use classification to be adopted To fix the size of mapping units, which depends upon the scale Interpretation of different land use/land cover classes Demarcation of doubtful areas Preparation of field land use/land cover map B. Field work: Type of ground data to be collected Selection of sample area for final classification Checking of doubtful areas 11

242 Change in land use/ land cover due to wrong identification, fresh Development, nomenclature. General verification C. Post field work: Reinterpretation or analysis or correction of doubtful areas Transfer of details on base map Marginal information Preparation of final land use/land cover map 12

243 Flowchart showing the methodology adopted for LU/LC mapping Basic data Data source Secondary data IRS LISS IV FMX Khariff season Rabi season Preparation of base maps Development of interpretation keys based on image characteristics. Interpretation and mapping of land use /land cover categories Validation and final interpretation key Ground verification of doubtful areas and modification of thematic details Transfer of Khariff and Rabi season land use/land cover details on to a single base map. Final land use/land cover map with symbols and colours Area estimation of each land use/land cover class. 13

244 Table 1.4 Land use / land cover Statistics of the study area S. No. LANDUSE AREA (Sq. km) % 1. BUILT UP LAND A. Settlements / Air Port WATERBODIES A. Reservoir / River etc CROP LAND A. Crop land WASTELANDS A. Land with scrub B. Land without scrub C. Mining area TOTAL

245 Figure 1.1 shows satellite imagery of the study area 15

246 Figure 1.2 shows land use / land cover of the study area 16