Executive Summary

EXECUTIVE SUMMARY

INTRODUCTION The Khagarijan Field of Oil India Limited (OIL) is a part of the Tinsukia PEL area located in Dibrugarh and Tinsukia districts of Assam. OIL had submitted Form-1 of the EIA Notification, along with a Draft Terms of Reference (ToR) for EIA study to MoEF. MoEF has issued approved ToR vide letter No. J-11011/105/2012-IA II (I) dated 18th July 2012. SENES India has been entrusted by OIL to undertake an Environmental Impact Assessment (EIA) study for Khagarijan Field located at the Dibrugarh and Tinsukia districts in Assam. The EIA study comprised of initial scoping & site visit, environmental monitoring & surveys, preparation of draft EIA-EMP report for Public Hearing (PH).

Block Location & Accessibility The Khagarijan Field of OIL covers approximately 675 sq. km area and is located in Dibrugarh and Tinsukia districts of Assam. The geographic location of the Khagarijan Field is included within the Survey of India’s Topo- Sheet No. 83M2, 83M3, 83M6 and 83M7. The Field is located to the south of the Brahmaputra River. NH 37(AT road) is the most prominent road in the region. The road runs through the southern side of Khagarijan Field, in an east to west orientation. This road connect Tinsukia town located in the south eastern corner of the Field, with Dibrugarh town located on the south western side, outside the Field. The northern side of the block is not easily accessible due to the stretch of Brahmaputra River on the west and Dibru-Saikhowa National park in the east. Tinsukia Junction and New Tinsukia Junction are the major railway stations within the Field and are located at the Guwahati-Dibrugarh line of North East Frontier railway whereas Mohanbari Airport is located within the Khagarijan field. Additionally, there are two Air Force bases within the field located at Chabua and Dinjan. Land Lease During the site selection process all the legal requirements will be considered for finalization of surface locations. Once the surface drilling location is finalized, land acquisition will be done including crop compensation. After finalization of drill site, OIL will procure the land from the land owners. The estimated land required per drill site is approximately 2.2 ha. Tentative well coordinates provided by OIL revealed 15 wells within plantation areas of tea garden, 12 wells are located in agriculture land, 2 wells located in household tea garden areas and 1 well within forest land. All the proposed drill sites are away from human habitation; therefore any displacement will not be required for this project. As displacement is not required, resettlement and rehabilitation is not applicable for this project.

PROJECT ACTIVITIES This activity involves • Well site preparation, construction of approach roads • Well drilling and testing. • Site closure and decommissioning of wells not indicative of potential hydrocarbon reserves.

Site Preparation & Construction Drill site Wells located on the agricultural land have no vegetation; whereas, wells located in the tea garden having tea bushes with shade trees. Site construction work will require clearing of tea bushes and some trees in the drill sites located in the tea garden. Site preparation will involve leveling, filling and consolidation of the site for staging equipment and machinery. Clearance of vegetation is the primary activity that will be undertaken during drill site construction. Following this, top soil will be scraped and stored for future use. The subsequent activities will involve elevating the drill platform by locally available fill material, construction of High Density Polyethylene (HDPE) lined pits for storage of drill cutting, waste mud and drilling wash water, construction of suitable storm water drainage system and construction of approach roads.

Drilling & Testing The drilling of wells is expected to be up to a depth of 4500 meters. Standard Land Rig or Mobile Land Rig with standard water based drilling fluid treatment system will be used for drilling. Drill cuttings generated will be collected and separated using a solid control system and temporarily stored on-site in HDPE lined pits (approximately 800 m3 capacity). Drilling and wash wastewater generated will also be stored at an onsite HDPE lined pit. The water will be adequately treated in a mobile Effluent Treatment Plant (ETP) to ensure conformance to the CPCB onshore oil and gas extraction industry effluent standards before disposal.

Site closure and decommissioning The drill sites will be properly reclaimed and rehabilitated if no commercial reserve has been established. This process will involve decommissioning of rigs and all machineries; disposal of drilling waste as per CPCB guidelines, disposal of fill materials, top soil restoration.

Project Utilities and Resource Requirements Power The power requirement during the site preparation and construction phase for each drill sites will be met through 125 KVA DG sets. Two (2) DG Sets of 1000KW capacity will be required for drilling purposes of which one will be kept as stand by. Lighting and other requirements will be met through 200 KW DG Sets. It is estimated that 3.5 KLD of diesel will be required during drilling phase.

Water Total water requirement for drill site preparation and construction phase of the project is estimated to be around 10 KLD. The total projected average consumption of water during drilling phase will be about 40 KLD per well including domestic purposes. Water will be sourced through bore well and permission will be taken from Ground Water Authority regarding abstraction of ground water for industrial purposes, if required. Manpower During the drilling phase, about 50 people will be working per shift. This will include technical experts, who will be responsible for various drilling related activities and some local workmen who will be hired from nearby villages for the entire duration of the project.

BASELINE ENVIRONMENTAL STATUS The study of the baseline environmental status helps in assessing the existing environmental conditions and identifying the critical environmental attributes. Baseline environmental study of the Khagarijan Field will comprise study of physical, biological and socio-economic environment where 30 exploratory and developmental wells will be drilled. Primary and secondary data were collected for conduction the EIA study. Physical Environment Climate and Meteorology The study area experiences a humid and warm sub-tropical climate throughout the year except for a cold winter in December till February. Hourly micro-meteorological data collected from primary meteorological station at Tinsukia town during the pre-monsoon reveals that the pre-dominant wind direction is from North West with the wind speed in the range of 1.0-1.5 m/s. Air Quality

The ambient air quality representing PM10, Sulfur Dioxide (SO2), and Nitrogen Dioxide

(NO2) was monitored at eight different locations for 24 hours twice a week during April-

June, 2013.Volatile Organic Carbons (VOCs), Methane (CH4), non-methane hydrocarbons (NMHCs) were monitored at a frequency of once a week for the same period. All the parameters were found to be in compliance to the National Ambient Air Quality Standards

(NAAQS), 2009. The average 24 hourly PM10 at the monitoring locations ranged between 3 3 47.38-71.94µg /m (NAAQS-100 µg/m ). The average 24 hourly NO2 at the monitoring 3 3 locations ranged between 13.70-18.27µg/m (NAAQS-80 µg/m ). The average 24 hourly SO2 concentration at 4 locations were found to be Below Detectable Limit (<4 µg/m3) whereas in other stations the average concentration ranged between 4.00-4.50 µg/m3 (NAAQS-80 µg/m3). Average value for methane hydrocarbon ranged between 2.29-2.83 ppm whereas the mean values of non methane hydrocarbon ranged between 0.38-0.75 ppm. Mean values of VOC at all sampling location varies in the range between 1.13-2.33 ppm.

Noise Quality The noise quality was monitored for 24 hours at Twenty (20) locations within the Khagarijan Field. Noise monitoring was conducted at areas in proximity to the proposed drill sites. Day time and nighttime equivalent noise levels varied between 50.0-62.7 dBA and 39.4-49.2 dBA respectively. The day time equivalent noise levels at 11 stations out of 20 revealed higher values were compared to the day time noise standards (55 dBA) for residential areas. The night time equivalent noise levels for 4 stations were found to be in exceedance to night time noise standards (45 dBA). Physiography and Geology The Khagarijan Field is included within the depositional plains of the River Brahmaputra and its tributaries. Physiographically, the Field can be classified as Low-lying alluvial belt. Upper Assam Basin is a proven petroliferous basin which represents a classic example of passive continental margin that evolved simultaneously with other east coast basins of India concomitant with rifting followed by drifting of the Indian Plate from eastern Gondwanaland and its subsequent subduction underneath the Burmese and Eurasian plates The basin has thrusted margins on three sides: to the south the Naga Hills Thrust Belt and Manipur Ophiolite Belt; to the east and north the Main Frontal Thrust of the Himalayas, which was active from the mid-Miocene to present day, bends around the Assam Syntaxis. Hydrogeology The annual replenishable ground water sources of Dibrugarh and Tinsukia district as per estimate of CGWB is 1,88,911 hectare metre (ham) and 1,59,036 ham respectively whereas the net ground water availability is found to be 1,79,465 ham and 1,43,132 ham respectively. The stage of groundwater development in Dibrugarh and Tinsukia district is found to be 15% and 12% respectively.

Groundwater Quality Groundwater samples were collected and analyzed as per IS: 10500 from Ten (10) locations within the Field. Almost all the parameters analyzed were under the acceptable and permissible limit of IS: 10500. It has been found that turbidity concentration at 4 locations in exceedance of acceptable limit whereas turbidity concentration at one monitoring location has exceeded the permissible limit. Iron concentration at 3 monitoring location found to be in exceedance of both acceptable and permissible limit. Watershed and Drainage The study area is included under the catchment of the River Brahmaputra which flows from the north eastern side to north western side. The channels traversing through the Field are Dibru River, Dinjan River etc.

Surface Water Quality Surface water was sampled from Brahmaputra River, Dibru River and Dinjan River. The water samples were analysed and compared with the CPCB Designated Best Use Classification of Surface Waters. The pH of the surface water samples varied from 7.1-7.3. The DO levels at all the locations exhibited values ranging from 6.3-7.0 mg/l. BOD values in all the surface water samples were detected at concentration below 3.00mg/l whereas COD value at the monitoring locations were found to be less than 4.00 mg/l except in one location. Electrical conductivity values of the samples ranged between 0.04-0.11 millisiemens/cm, sodium absorption ratio varied between 0.09-0.19.The total Coliform counts of the surface water samples varied between (11MPN/100ml - 80MPN/100ml). The surface water is primarily being used for irrigation, bathing, cleaning and for catching fish, the obtained results justified their use compliance with the CPCB Water use Criteria. Land Use Majority of the land (28.66%) within the Khagarijan Field is covered by the main course of Brahmaputra River, Dibru River, other small channels, riverbed and water bodies. Tea Garden covers 21.31% of the field whereas 14.8% land is used for agricultural purposes. On the other hand, 9.91% of land is covered by grassland whereas 8.97% of the total field area is covered by Forest area comprising primarily of Dibru-Saikhowa National Park and Padumoni segment of Bherjan-Borajan-Padumoni Sanctuary. Settlement and homestead land plantation comprises about 12% of total area whereas defense installation covers about 1.91 % of total field area.

Soil Quality Soil of Brahmaputra valley of which the Field is a part, is characterized by the presence of fertile alluvial soil. The primary analyses of the soil samples from Agricultural, Tea Garden and Forest Land at 5 locations in the study area shows that the soils are sandy loamy and clayey in nature with a pH range of 3.53-4.99. The soils revealed high available nitrogen content (374.92-490.28mg/kg). The micronutrient levels observed in the soil samples do not indicate any extraordinary enrichment of metals or contamination from any external sources. Natural Hazards The study area lies in Zone V of the Bureau of Indian Standard (BIS) 2000 which might encounter earthquakes of maximum intensity. It was revealed from Flood Hazard Maps (1998-2007) prepared by National Remote Sensing Agency (NRSA) that part of the Khagarijan Field is flood prone, but majority of the proposed exploratory and development wells are not located at the flood prone zones.

Biological Environment Baseline survey and Secondary data received from Forest Department’s Website and other published and unpublished document revealed that about 51 sq.km. area within the Block is included under Dibru-Saikhowa National Park. Along with that, 1.76sq.km. of Padumoni

Segment of Bherjan-Borajan-Padumoni Sanctuary of Tinsukia district is also located within this Field. Biogeographically, the region exhibits the properties of both the Indian and Malayan Sub-regions. Under the classification of Wild Life Institute, Dehradun, this area falls within North Eastern India Brahmaputra valley Bio-geographical province. About 31 species of Schedule-I animals were reported from the study area which included critically endangered species like Bengal Florican, White Ramped Vulture and Slender billed Vulture.

Socioeconomic Environment Tinsukia district of Assam comprises of 3 administrative divisions which is further subdivided into 7 Nos. C.D. Blocks. The total population of the district as per 2011 provisional census data is 1316948 with a decadal growth rate of 14.51%. The sex ratio is 948 and the population density is 347 per sq.km. On the other hand, Dibrugarh district of Assam comprises of 7 administrative divisions which is further subdivided into 7 Nos. C.D. Blocks. The total population of the district as per 2011 provisional census data is 1327748 with a decadal growth rate of 11.92%. The sex ratio is 961 and the population density is 392 per sq.km.

Socioeconomic profile Forty Nine (49) villages within the study area were selected for developing the socioeconomic profile of the area. It was seen from the Census Data of 2001, Balijan Tea Estate has the highest population (5124 persons). The highest literacy rate (74.54%) was observed in Dinjoy Satra and the least was found in Nokhroy TE. Major population of the study area villages are either workers in nearby Tea Estates or involved in Agricultural crop cultivation as a source of their livelihood.

Socioeconomic Infrastructure Of the study area villages located in the Field almost all the villages have electricity, drinking water facility and educational facilities. In terms of educational facilities, 37 villages among the identified villages for socioeconomic study are having primary schools. Middle schools and senior secondary schools are present in 11 and 4 villages respectively.

IMPACT ASSESSMENT The potential impacts of the project on different components of the environment was systematically identified and evaluated for significance. The principal concerns that emerged are:

Impact on Air Quality The operation of DG sets, movement of vehicles and machineries during construction and drilling at drill sites will result in the generation of air pollutants viz. PM, NOx and SOx which may affect the ambient air quality temporarily. Air pollutants like NOx will also be generated as a result of flaring of natural gas.

Impact on Noise Quality Operation of heavy machinery/equipments and vehicular movement during site preparatory, road strengthening/construction activities may result in the generation of increased noise levels. Operational phase noise impacts are anticipated from operation of drilling rig and ancillary equipment viz. shale shakers, mud pumps and diesel generators.

Impact on Soil Quality Stripping of top soil will affect the soil fertility of the well sites. Potential impact on soil quality may result from storage and handling of fuel, lubricants and from storage and handling of drilling mud and drill cuttings.

Impact on Topography and drainage Elevating the land to about 1 m from the ground level during site preparation may lead to alteration of onsite micro-drainage pattern. This might lead to the flow of untreated waste water and excess rain water to the adjoining agricultural land thereby adversely impacting the fertility of the soil.

Impact on Water Quality and Hydrology The surface run off from drilling waste (cuttings and drilling mud), hazardous waste (waste oil, used oil etc) and chemical storage facilities on open soil is likely to contaminate if allowed to flow into nearby water bodies viz. natural drainage channels, ponds etc. Possibility of contamination of subsurface and unconfined aquifers may exist if the casing and cementing of the well is not carried out properly leading to infiltration or seeping of drilling chemicals or mud into porous aquifer region.

Impact on Biological Environment Majority of the wells are located on manmade ecological habitat, only one well is located in forest land. Out of 30 planned wells, 14 wells falls within 10km of both Dibru Saikhowa National Park as well as Bherjan Borjan Padumoni Wild life Sanctuary and 14 wells are located within 10km of only Dibru Saikhowa National Park and 1 well is situated within 10 km of only Bherjan Borajan Padumoni Wild Life Sanctuary. Noise generated from drilling activity, lighting at well site, traffic movement will cause disturbance to wildlife. Taking presence of protected ecological habitats and Schedule I in proximity to the proposed well sites, impact on fauna and faunal habitat is considered to be of high significance. Few well sites are located close to the Brahmaputra River or the Maguri-Motapung wetland complex. Therefore, in case of any discharge of untreated waste water from drilling site may result in the possible contamination of receiving streams and their ecological habitat. Surface runoff during monsoon from the construction site of the wells has the potential to contaminate receiving surface water bodies thereby impacting their aquatic ecology.

Impact on Socio economic Environment The proposed well sites are located both on agricultural land, homestead tea gardens and plantation area of tea estates. The proposed project would not require any displacement of villagers. Impact on socio economic environment is attributed to loss of livelihood, conflicts on job opportunity, disruption of infrastructure, discomfort due to dust and noise, ecological productivity of agricultural land, influx of population etc. The project will benefit the people living in the neighboring villages by giving preference to them in relation to direct & indirect employment associated with the various project activities and boosts the local economy. The proposed project will also involve the improvement of existing road and/or bridge condition thereby enabling the transportation of drilling rig and ancillary equipment.

QUANTITATIVE RISK ASSESSMENT The quantitative risk assessment has been done to provide a systematic analysis of the major risks associated with exploratory and development drilling activities in Khagarijan Field. Oil spills, loss of well control/blow-out and process leaks constitute the major potential hazards of onshore drilling. Based on Frequency Analysis Method, it has been estimated that the likelihood of a blowout is Occasional/Rare at a rate of 7.5X10-2. Thus the Blow out frequency for the proposed project is calculated at 2.25 X 10-1 per well drilled.

ENVIRONMENTAL MANAGEMENT PLAN Site-specific Environment Management Plans (EMP) has been developed to prevent and mitigate significant adverse impacts and accentuate beneficial impacts will be implemented by OIL for the proposed project. The key mitigation measures specific for each management plan have been discussed in the Table below:

Sl. Environment Key Mitigation Measures No Management Plan Pollution 1 • The top soil generated from site clearance activities will be stored in Prevention and designated area and stabilized to prevent fugitive dust emissions. Abatement Plan • Preventive maintenance of DG sets to be undertaken as per manufacturers schedule to ensure compliance with CPCB specified generator exhaust. • All vehicles, equipment and machinery used for construction will be subjected to preventive maintenance as per manufacturer norms. • Flaring will be undertaken in accordance with the CPCB Guidelines for Discharge of Gaseous Emissions for Oil & Gas Extraction Industry. • High combustion efficiency, smokeless flare/burner will be used. • Installation of acoustic enclosures and mufflers on engine exhaust of DG sets to ensure compliance with generator noise limits specified

Sl. Environment Key Mitigation Measures No Management Plan by CPCB. • Setup effective noise barrier at the fence-line of the site. • Fuel and chemical storage areas will be paved and properly bunded. • Run-off discharges to natural drainage channels/water bodies to conform to CPCB Inland Water Discharge Standards. • Proper casing and cementing of drilling well will be done to prevent contamination of sub-surface aquifers. • Water based mud to be used as a drilling fluid 2 Waste • Use of low toxicity chemicals for the preparation of drilling fluid. Management Plan • Storage of drill cuttings in impervious HDPE lined pits • Disposal of wash water will be achieved after necessary treatment to comply with the CPCB onshore effluent discharge standard for oil and gas industry. • Necessary spill prevention measures viz. spill kit will be made available at the hazardous material storage area • The hazardous waste (waste and used oil) will be managed in accordance with Hazardous Waste (Management, Handling & Transboundary Movement) Rules, 2008 • The kitchen waste will be disposed in nearest municipal dumping site on a daily basis through approved waste handling contractors • The sewage generated will be treated in a combination of septic tank and soak pit. • Used batteries will be recycled through the vendors supplying lead acid batteries as required under the Batteries (Management & Handling) Rules, 2001. • Recyclables will be periodically sold to local waste recyclers. 3 Wild Life • The drill site will be properly fenced (chain-linked) to avoid straying of any outsider as well as wildlife; Management Plan • No temporary electric supply connection line from the grid will be laid for the proposed project activity. All electric requirements will be supplied from the internal DG sets. • Noise Levels at the drill site will be controlled through selection of low noise generating equipment and installation of sufficient engineering controls viz. mufflers, silencers etc. • Movement of heavy vehicles will be restricted at night time • In case of any accidental injuries to any wild animal by any project related activity, a Veterinary Doctor’s help will be taken 4 Road Safety & • Project vehicular movement involved in sourcing and transportation Traffic of borrow material will be restricted to defined access routes. Management Plan • Precautions will be taken to avoid damage to the public access routes including highways during vehicular movement. • Clear signs, flagmen & signal will be set up at major traffic junctions and near sensitive receptors viz. primary schools in discussion with

Sl. Environment Key Mitigation Measures No Management Plan Gram Panchayat and local villagers. • Movement of vehicles during night time will be restricted. Speed limits will be maintained by vehicles involved in transportation of raw material and drilling rig. • A Journey Management Plan will be formulated and implemented by the contractor to control construction and operational phase traffic. • Routine maintenance of project vehicles will be ensured to prevent any abnormal emissions and high noise generation. • Adequate training on traffic and road safety operations will be imparted to the drivers of project vehicles. Road safety awareness programs will be organized in coordination with concerned authorities to sensitize target groups viz. school children, commuters on traffic safety rules and signage. 5 Occupational • All machines to be used in the construction will conform to the Health & Safety relevant Indian Standards (IS) codes, will be kept in good working order, will be regularly inspected and properly maintained as per IS Management Plan provisions and to the satisfaction of the site Engineer. • Contractor workers involved in the handling of construction materials viz. borrow material, cement etc. will be provided with proper PPEs viz. safety boots, nose masks etc. • No employee will be exposed to a noise level greater than 85 dB(A) for a duration of more than 8 hours per day. Provision of ear plugs, ear muffs etc. and rotation of workers operating near high noise generating areas. • All chemicals and hazardous materials storage container will be properly labeled and marked according to national and internationally recognized requirements and standards. Materials Safety Data Sheets (MSDS) or equivalent data/information in an easily understood language must be readily available to exposed workers and first-aid personnel. • The workplace must be equipped with fire detectors, alarm systems and fire-fighting equipments. Equipments shall be periodically inspected and maintained to keep good working condition. • Adequate sanitation facilities will be provided onsite for the operational workforce both during construction and operational phase of the project. • Training programs will be organized for the operational workforce regarding proper usage of PPEs, handling and storage of fuels and chemicals etc. 6 Management of • People from adjoining areas especially given job preference through Social issues and local contractors according to the skill sets possessed. concerns • Prior to the commencement of the proposed activity, a consultation program will be conducted by OIL with the target groups and local authorities. The primary objective of such consultation will be to share with the concerned villagers/stakeholders the objective of the

Sl. Environment Key Mitigation Measures No Management Plan proposed project associated impacts and their mitigation. • OIL will give more emphasis and priority on periphery development, development of health facilities and provision for drinking water facility as per Corporate Social Responsibility (CSR) Plan. • During the drilling phase and for the rest of the project activities proper safety measures will be undertaken both for transportation as well as the other operations. • The drill site would be fenced and gates would be constructed so that the children are refrained from straying into the site. 7 Emergency • Drilling rig and related equipments to be used for development drilling will be conformed to international standards specified for Response Plan such equipment. • Blow-out preventers and related well control equipment shall be installed, operated, maintained and tested generally in accordance with internationally recognized standards. • Appropriate gas and leak detection system will be made available at each of the drilling location. • Adequate fire-fighting equipment shall be provided at each drilling site

The EMP has been designed with a flexibility so that it can be monitored and adapted to future changes in project design, scope, or the environment and be seamlessly integrated and implemented by OIL.

PROJECT COST An estimated cost of INR 600 Crore will be expended for the drilling of thirty exploratory and development wells. The budget for implementation of the EMP is INR 153.1 Lakhs.