APPENDIX- I

(See paragraph – 6)

FORM- I

(I) Basic Information:

S.No. Item Details

1 Name of the project Amendment in term of reference

(TOR) issued by MOEF File No. J-11011-92-2012 IA II(I) dated 13th

July,2012

2 S. No. in the schedule 1

3 Proposed

capacity/area/length/tonnage to be handled/command area/lease

area /number wells to be drilled

Drilling of 268 additional oil and

gas wells in the Gamij field of ONGC Ahmedabad besides the 138

oil and gas wells as mentioned in the existing TOR No. J-11011-92-

2012 IA II(I) dated 13th July,2012

4 New/Expansion/Modernization Expansion within existing mining lease area.

5 Existing Capacity/Area etc. Area : 1649.917 sq. km Coordinates Gamij Field ( field

where additional development

wells are requested): Lattitude- 72 55 .58.01 (N) Longitude—23 55 0.01(E)

6 Category of Project .i.e.' A' or 'B’ A

7 Does it attract the general condition? If yes, Please specify.

No

8 Does it attract the specific condition? If yes, Please specify.

No

9 Location

Plot/Survey/Khasra No. Village

Tehsil District

State

ML Area of Gamij

District: Kheda Village: Gamij

Taluka: Dehgam State : Gujarat

10 Nearest railway station/airport Distances from office in

along with Distance in kms.

Chandkheda Ahmedabad

Nearest Railway station-Kalol Railway Station:-

(15 Kms)

Airport- (30Kms)

11 Nearest Town, city, District

Headquarters Along with distance in kms.

Kheda

Approx. distanace:

12 Village Panchayats, Zilla Parishad ,

Municipal Corporation, Local body (complete postal Address with

telephone nos. to be given)

Map showing villages with

respective Talukas and districts enclosed in Table-1

13 Name of the applicant Shri Yash Malik

ED-Asset Manager ONGC, Ahmedabad Asset

Avani Bhavan, Chandkheda

Ahmedabad-380005 Gujarat

14 Registered Address ONGC

Jeevan Bharti Building Tower II

124 Indira Chowk New Delhi-110001

Delhi, India

15 Address for correspondence:

Name

Designation(Owner/Partner/CEO) Address

Pin Code E-mail

Telephone No. Fax No

Shri Yash Malik

ED-Asset Manager

ONGC, Ahmedabad Asset Avani Bhavan,

Chandkheda Ahmedabad-380005

Gujarat Tel: 079-23290050

Fax: 079-23291289 Email : malik_yash@ongc.co.in

16 Details of Alternative Sites examined, if any.

Location of these sites should be

shown on a topo sheet.

NA

17 Interlinked Projects After drilling, oil and gas wells

found viable, oil will be transported

to nearby Group Gathering Stations for processing and transportation

thereafter.

18 Whether separate application of

interlinked

Project has been submitted?

No

19 If yes, date of submission NA

20 If no, reason Consolidated Consent and

authorization (CCA) has already

been obtained for all GGS/CTF from Gujarat Pollution Control Board.

21 Whether the proposal involves approval/clearance under: if yes

details of the same and status to be given.

(a)The Forest (Conservation) Act, 1980?

(b)The Wildlife(Protection) Act, 1972?

(c) The CRZ Notification, 1991?

No

22 Whether there is any Govt Order/policy relevant/relating to

the site?

No

23 Forest land involved(hectares) Nil

24

Whether there is any litigation pending against the project and/or

land in which project is propose to be set up ?

(a) Name of the court (b) Case No

(c) Order/Directions of the Court, if any and its relevance with the

proposed project

No

(II) Activity:

1. Construction, operation or decommissioning of the Project

involving actions, which will cause physical changes in the locality (topography, land use, changes in water bodies, etc.)

S.No.

Information/Checklist confirmation

Yes/No

Details thereof

(with approximate quantities / rates,

wherever possible) with source of

information data

1.1 Permanent or temporary change in land use, land cover or topography including

increase in intensity of land use (with respect to local land use plan)

Yes Drilling an oil well is a temporary and time

bound activity. Once the well is drilled the

equipment facilities and waste are removed. Drill

cuttings, unused drilling fluid and waste water is

collected in a polythene lined pit which is dried

and covered with local

soil after completion of drilling and testing

activities in accordance to the conditions

stipulated in earlier Environmental Clearance

from MOEF. Rest of the solid waste is

transported to land fill area. Entire drill site area

is retained by ONGC.

1.2 Clearance of existing land, vegetation and buildings?

Yes Drilling land is procured strategically so as to

cause minimum most alteration to native

ecology. Clearance is confined to removal of

bushes and leveling of area to render it suitable

for drilling operation.

1.3 Creation of new land uses? Yes Area of land is retained for operation and

maintenance of the

drilled oil and gas well.

1.4 Pre-construction investigations e.g. bore houses, soil testing?

Yes Only surface hardening for vehicle and material

movement

1.5 Construction works? Yes Confined to surface hardening to make

foundation for installation of drilling rig

and equipment, preparation of waste

water pit and barbed wire boundary enclosing

the site etc.

1.6 Demolition works?

No

1.7 Temporary sites used for construction works or housing of construction

workers?

Yes Construction is confined to erection of temporary

hut for security guards for the period of drilling

and testing.

1.8 Above ground buildings, structures or earthworks including linear structures,

cut and fill or excavations

No Hardening of surface to provide firm foundation

to drilling rig and equipment. A kuchcha

(earthen) pit of approximately 1500m3 is

excavated and lined with impervious lining to store

drill cutting, unused drilling fluid and waste

water generated in the

process of drilling activities.

1.9 Underground works including mining or tunneling?

Yes Vertical / angled excavation of oil wells

ranging from 1100 meters to 2300 meters

approx.

1.10 Reclamation works? No Drill cuttings and unusable chemical

drilling fluid is stored in excavated pit with

impervious lining which is topped with native

soil. Other left over

waste is collected and transported on need

basis to land fill (TSDF) site of which Ahmedabad

Asset is member. In case of generation of any

amount of waste oil, it is confined and subjected

to bioremediation through consortium of

bacteria in association

with M/S OTBL( ONGC teri biotechnology

Limited ) to restore the soil to back to normal.

1.11 Dredging? No

1.12 Offshore structures? No

1.13 Production and manufacturing

processes?

No Production process is

limited to well testing only which is

accomplished by test flowing the well in a steel

tank for complete recycling and nil

interface with land environment.

1.14 Facilities for storage of goods or

materials?

Yes Storage is done in the

mobile bunk houses. For temporary storage of

chemicals used for rheological modification

of drilling fluid, a temporary shed / store is

made.

1.15 Facilities for treatment or disposal of

solid waste or liquid effluents?

Yes An approximately

1500m3 kuchcha

(earthen) pit is excavated to store drill

cutting an waste water generated in the process

of drilling activities. Drill cuttings and

unusable chemical

drilling fluid stored in excavated pit which

topped with native soil. Other left over

hazardous waste is collected and transported

on need basis to land fill (TSDF) site of which

Ahmedabad Asset is member. In case of any

amount of waste oil, it is

confined and subjected to bioremediation

through consortium of bacteria in association

with M/S OTBL, to restore the site back to

normal. In the wake of

notification from ministry of environment and

forest GSR.546(E) dated 30th August 2005

regarding disposal of solid waste, drill cutting

and drilling fluid for

onshore drilling operation, Asset has

planned each drill site to have a provision of pits

with impervious linings to store and disposed of

drill cuttings and unusable drilling fluid in

accordance with the laid down guidelines.

1.16 Facilities for long term housing of

operational workers?

No Not applicable

1.17 New road, rail or sea traffic during

construction or operation?

No Existing Road facilities

are used however approach road from

existing road to drill site is constructed for

transportation of man

and materials.

1.18 New road, rail, air waterborne or other

transport infrastructure including new or altered routes and stations, ports,

airports etc?

No Approach roads are

prepared by way of hardening the surface to

transport rig and

equipment for drilling and subsequent

monitoring and corrective actions to

maintain the oil wells.

1.19 Closure or diversion of existing

transport routes or infrastructure leading to changes in traffic

movements?

No Not applicable

1.20 New or diverted transmission lines or pipelines?

No Not applicable

1.21 Impoundment, damming, culverting, realignment or other changes to the

hydrology of water courses or aquifers?

No

1.22 Stream crossings? No Not applicable

1.23 Abstraction or transfers of water from ground or surface waters?

Yes Usually ground water is used for preparation of

chemical fluid, cooling water and other technical

purpose.

1.24 Changes in water bodies or the land surface affecting drainage or run-off?

No Not applicable

1.25 Transport of personnel or materials for construction, operation or

decommissioning?

Yes During construction, operation and

decommissioning and

subsequent work over operations.

1.26 Long-term dismantling or decommissioning or restoration works?

Yes Subsequent to rig release, the site is

cleared of all drilling items and leftover.

1.27 Ongoing activity during

decommissioning which could have an impact on the environment?

No Decommissioning activity

involves total shifting of rig and associated

equipment for use at other site as well as re

filling and restoration of

waste pit.

1.28 Influx of people to an area in either temporarily or permanently?

No Not applicable

1.29 Introduction of alien species?

No Not applicable

1.30 Loss of native species or genetic

diversity?

No Not applicable

1.31 Any other actions? No

2. Use of Natural resources for construction or operation of the Project (such as land, water, materials or energy, especially

any resources which are non-renewable or in short supply):

S.No.

Information/checklist confirmation

Yes/No

Details thereof (with approximate quantities

/rates, wherever possible) with source of information

data

2.1 Land especially undeveloped or agricultural land (ha)

Yes Approx 110m x 110m land is acquired for drilling at a

location depending upon the geological and geophysical

surveys. Mostly agricultural land and not the forest land

is acquired. In most of the cases clusters wells are

drilled from existing sites so as not to alter any

biodiversity of the new area.

2.2 Water (expected source & competing users) unit: KLD

Yes Underground water is used.

Past consumption trend divulges an average

consumption of approx. 1950 KL of water for drilling an

oil/gas well.

2.3 Minerals (MT) Yes Some minerals like bentonite, barites etc. as listed in

feasibility report are consumed in the process of

preparation of drilling fluid.

2.4 Construction material – stone, aggregates, sand / soil (expected

source – MT)

Yes For hardening of site to

render it fit for drilling operations.

2.5 Forests and timber (source – MT) No

2.6 Energy including electricity and

fuels (source, competing users) Unit: fuel (MT), energy (MW)

Yes HSD Approx 45 KL per well

2.7 Any other natural resources (use

appropriate standard units)

No

3. Use, storage, transport, handling or production of substances

or materials, which could be harmful to human health or the

environment or raise concerns about actual or perceived risks to human health.

S.No

Information/Checklist confirmation

Yes/

No

Details thereof (with

approximate quantities/rates,

wherever possible) with source of

information data

3.1 Use of substances or materials, which are

hazardous (as per MSIHC rules) to human health or the environment (flora, fauna,

and water supplies)

Yes Usually water based

Drilling fluid with Bentonite as base

component and barites as weighing material is

used , chemicals used to

maintain rheological characteristics of drilling

fluid are usually biodegradable chemicals.

However, some drilling fluid like Caustic, chrome

lignite, chrome lignosulfate etc. are

hazardous material used

in small quantities

MSDS pertaining to these chemicals remain

available at site.

3.2 Changes in occurrence of disease or affect

disease vectors (e.g. insect or water borne diseases)

No

3.3 Affect the welfare of people e.g. by changing living conditions?

Yes Construction of roads and hardening of roads

in rural areas help the

residents of the area by way of improved

infrastructural facilities like road transportation

and generation of local employment. Since the

wells are located in remote areas way from

the human settlement. On the top of it, Asset

management undertakes welfare activities in

societal areas adjacent to its operation under

Corporate Social

Responsibility policy of organization.

3.4 Vulnerable groups of people who could be affected by the project e.g. hospital

patients, children, the elderly etc.,

No Usually drill sites are away from societal areas

3.5 Any other causes No

4. Production of solid wastes during construction or operation or

decommissioning (MT/month)

S.No

.

Information/Checklist confirmation

Yes/

No

Details thereof (with

approximate quantities/rates,

wherever possible) with source of

information data

4.1 Spoil, overburden or mine wastes Yes Drill cuttings and left over unusable drilling

fluid ,if any

4.2 Municipal waste (domestic and or commercial wastes)

Yes Insignificant quantity of domestic waste which is

addressed by soak pit.

4.3 Hazardous wastes (as per Hazardous Waste Management Rules)

Yes Drill cuttings Drilling mud unless

proved otherwise with reference to

concentration of specific

constituents Oil soaked cotton

waste and cotton gloves

Quantitative estimates: Drill cuttings: 75

to 160m3

Unused drilling mud: 120 to 170 m3

4.4 Other industrial process wastes Yes Insignificant amount of empty bags and sacks

etc.

4.5 Surplus product Nil

4.6 Sewage sludge or other sludge from effluent treatment.

No Effluent usually contains dissolved and suspended

native constituents like bentonite and barites

with very little quantity of oil carried over due to

small leakages from

various pumps

4.7 Construction or demolition wastes No

4.8 Redundant machinery or equipment Nil

4.9 Contaminated soils or other materials Yes During operation soil

does in contact with drill

cuttings, drilling fluid and oil during testing. The

environment management plan and

procedures are in place

to address these aspects.

4.10 Agricultural wastes. No

4.11 Other solid wastes No

5. Release of pollutants or any hazardous, toxic or noxious substances to air (Kg/hr)

S.No.

Information/Checklist confirmation

Yes/

No

Details thereof (with approximate

quantities/rates, wherever possible)

with source of information data

5.1 Emissions from combustion of fossil fuels

from stationary or mobile sources

Yes From DG sets which

run on HSD for power generation. Ambient air

quality monitoring (AAQM) IS

CONDUCTED ON HALF YEARLY BASIS AS

PART OF ANNUAL PLAN UNDER Environment

management system based on ISO 14001

maintained by each rig of the asset.

5.2 Emissions from production processes Yes

Hydrocarbon emission

during production testing which is done in

steel tanks to recycle the entire amount of

the liquid hydrocarbon produced in the

process.

5.3 Emissions from materials handling including storage or transport

Yes Vehicular emission engaged for

transportation. These vehicles essentially

hold pollution under control certificates and

controlled by Logistics department – an

ISO14001 certificate

establishment of asset.

5.4 Emissions from construction activities including plant and equipment

Yes Emission from earth movers during site

preparation.

5.5 Dust or odors from handling of materials

including construction materials, sewage and waste

Yes insignificant

5.6 Emissions from incineration of waste No

5.7 Emissions from burning of waste in open air (e.g. slash materials, construction

debris)

No

5.8 Emissions from any other sources No

6. Generation of Noise and Vibration, and Emissions of Light and Heat:

S.No.

Information/Checklist confirmation

Yes/No Details thereof

(with approximate

quantities/rates, wherever possible)

with source of information data

6.1 From operation of equipment e.g. engines, ventilation plant, crushers

Yes

Emissions like noise, vibrations and heat

are generated from DG sets, Mud pumps,

Draw works, Shale

shakers, De sanding and De silting

systems, Chemical dosing (Hopper)

system and motors on mud tanks etc.

Condition Monitoring is carried out

regularly and corrective actions are

taken to minimize vibrations and

emissions.

6.2 From industrial or similar processes No

6.3 From construction or demolition Yes Due to plying of

heavy vehicles and earth movers during

construction of site, rig building, testing

and dismantling of operations.

6.4 From blasting or piling

No

6.5 From construction or operational traffic

Yes Noise

All the plying vehicles maintain pollution

under control certificate.

6.6 From lighting or cooling systems

Yes Insignificant as

Drilling Rigs oftenly operates in areas

away from societal areas.

6.7 From any other sources No

7. Risks of contamination of land or water from releases of

pollutants into the ground or into sewers, surface waters, groundwater, coastal waters or the sea:

S.No.

Information/Checklist confirmation

Yes/ No

Details thereof (with approximate

quantities/rates, wherever possible) with

source of information data

7.1 From handling, storage, use or spillage

of hazardous materials

Yes Drill cuttings

Left over unusable mud

7.2 From discharge of sewage or other effluents to water or the land (expected

mode and place of discharge)

Yes Effluent usually contains dissolved and suspended

native constituents like bentonite and barites with

very little quantity of oil carried over due to small

leakages from various pumps. This effluent is

passed through a waste pit system compartmentalized to

skim physical oil and make it

recyclable.

7.3 By deposition of pollutants emitted to

air into the land or into water

No

7.4 From any other sources

No

7.5 Is there a risk of long term build up of

pollutants in the environment from these sources?

No

8. Risk of accidents during construction or operation of the Project, which could affect human health or the environment

S.No.

Information/Checklist confirmation

Yes/ No

Details thereof (with

approximate

quantities/rates, wherever possible) with

source of information data

8.1 From explosions, spillages, fires etc from storage, handling, use or

production of hazardous substances

Yes Explosion of charge on the surface during

making up of perforation strip or

gun

Blowout with or without fire

Loss of radioactive material during logging of wells

8.2 From any other causes

Yes Human injuries during various related operations

at derrick floor in particular. All rigs maintain third party

certified HSE management based on OHSAS 18001

8.3 Could the project be affected by

natural disasters causing environmental damage (e.g. floods,

earthquakes, landslides, cloudburst etc)?

No Natural disasters like

earthquake/flood may cause disastrous conditions. Asset

maintains disaster management plan to

respond to such conditions.

9. Factors which should be considered (such as consequential

development) which could lead to environmental effects or the potential for cumulative impacts with other existing or

planned activities in the locality

S.

No.

Information/Checklist confirmation

Yes

/No

Details thereof (with

approximate quantities/rates, wherever

possible) with source of information data

9.1 Lead to development of supporting utilities, ancillary development or

development stimulated by the project which could have impact on the

environment e.g.:

• Supporting infrastructure (roads, power supply, waste or waste water

treatment, etc.)

• housing development

• extractive industries

• supply industries

• other

Yes

Laying of under

ground(beneath one meter) oil and gas flow lines from

wells to nearby group gathering station, a facility to

process the crude oil and gas

9.2 Lead to after-use of the site, which could have an impact on the

environment

Yes Work over operations is carried out restore the

production from the well in case of any anomaly. This

activity may generate some waste like cotton waste, hand

gloves, house keeping waste etc.The effluent generated

during the process in flowed down to related group

gathering station for subsequent treatment and

disposal.

It is notable that each work over rig of the Asset is

maintaining third party

certified Environment

Management System based on ISO-14001 which testifies

its environmentally sound operations.

9.3 Set a precedent for later developments Yes - During drilling activities of

the asset maintains a set of environmental policy and

procedures in conformance to the EMS-ISO-14001 which

ensures extraction of hydrocarbon in

environmentally sound manner.

9.4 Have cumulative effects due to proximity to other existing or planned

projects with similar effects

No

(III) Environmental Sensitivity

S.No Areas

Name/

Identity

Aerial distance (within

15 km.) of Proposed

project location boundary

1 Areas protected under international conventions, national or local

legislation for their ecological, landscape, cultural or other related

value

No

2 Areas which are important or sensitive for ecological reasons -

Wetlands, watercourses or other water bodies, coastal zone,

biospheres, mountains, forests

No

3 Areas used by protected, important or

sensitive species of flora or fauna for breeding, nesting, foraging, resting,

over wintering, migration

No

4 Inland, coastal, marine or underground waters

No

5 State, National boundaries No

6 Routes or facilities used by the public for access to recreation or other

No

tourist, pilgrim areas

7 Defense installations No

8 Densely populated or built-up area No

9 Areas occupied by sensitive man-made

land uses (hospitals, schools, places of worship, community facilities)

No

10 Areas containing important, high

quality or scarce resources (ground water resources, surface

resources, forestry, agriculture, fisheries, tourism, minerals)

No

11 Areas already subjected to pollution or environmental damage. (those where

existing legal environmental standards

are exceeded)

No

12 Areas susceptible to natural hazard

which could cause the project to present environmental problems

(earthquakes, subsidence, landslides, erosion, flooding or extreme or

adverse climatic conditions)

Nil

Proposed Term of Reference (TOR) - NIL

Explanatory Note:-

In the wake of updating of reservoir data of Gamij field of ONGC Ahmedabad, excellent potential of the field with reference to hydrocarbon

could be established. Subsequently, it was decided to drill more development wells in this field to monetized the field at the

earliest.Earliar 52 wells were planned in this field whereas after recent development 268 more wells have been planned to be drilled in this field.

This will significantly prop up the production of oil and gas and thus, plan

of drilling additional wells is in the interest of nation.

Compliance Status:-

Monitoring of Ambient Air Quality,stacks and noise is carried out at

each drilling Rig through third party and results have been found within prescribed limits.

Noise data Status is shown in the table:-

Duration Prescribed Limit

(Industrial Area) (Db) Range of Study Area

(dB)

Day Time (6:00hrs -22:00 hrs)

75 53.1 - 55..4

Night Time (22:00hrs -6:00 hrs)

70 42.7 - 45.8

I hereby given undertaking that data and information given in the application and enclosures are true to best of my knowledge and belief

and I am aware that if any part of the data and information submitted is found to be false or misleading at any stage, the project will be

rejected and clearance give, if any to the project will be revoked at our risk and cost.

Date: Signature of the applicant

With Name and Full Address

Place: (Project proponent/Authorised Signatory)

FEASIBILITY REPORT FOR PROPOSED PROJECT:

Executive Summary

ONGC - Parent Company Oil and Natural Gas Corporation Ltd( ONGC) a maharatna company, is engaged in commercial exploitation of hydrocarbon from approx. 68 % of the India’s total petroleum mining lease area. It is operating in 302 petroleum mining leases in onshore areas and 33 in offshore areas. After deregulation of Oil Sector in India, the corporation has vigorously pursued to realize its vision of being world class Oil and Gas Company integrated in energy business with dominant Indian leadership and global presence.ONGC ,as flagship energy company of India and Asia’s numero uno exploration and production company has a well defined task of securing sustained energy supplies to India at affordable prices through innovative solutions while managing various challenges including strict environmental standards. In order to meet its objectives, company has established its global footprints by acquiring 34 projects in 16 countries namely Vietnam, Iran, Iraq, Libiya, Sudan, Myanmar, Syria, Brazil, Egypt, Cuba,Nigeria,Syria,Qatar,Colombia,Russia, and Turkmenistan through its wholly owned subsidiary ONGC Videsh Ltd. ONGC and has entered into refining sector by acquiring MRPL . Thus, ONGC has emerged multinational company and a group of companies. ONGC’s head office is at Dehradun whereas its registered office is in Delhi.The company has an asset based organisational structure and has seven on shore and four offshore producing assets in India. It has a strong workforce of approx. 35000 technically competent &skilled employees spread all over India.Ahmedabad Asset are one of its major onshore asset in cambay basin of Gujarat State.

Ahmedabad Asset Since its inception in 1961,Ahmedabad asset is one of the major onshore assets of ONGC operating in four revenue districts of Gujarat state viz. Kheda. Ahmedabad, Gandhinagar and Mehsana. Operations of Ahmedabad asset are divided in to four areas spread across about 6200 square kilometers.The Asset has following installations and establishments

Drilling Rigs- 06(own) and 01(contract) Work Over Rigs -08 (own) and 05(on contract) Production Installations-35

Auxiliary Services - Logging Services, Cementing Services, Asset Workshop, Logistic Services, Asset Chemistry laboratory Support Services:HR/ER, Finance, Material Management,Legal,Medical and security Corporate Services: Planning,Infocom,Vigilance,Audit,Marketing and communication.

There are 23 oil fields divided into Geographical areas in the Asset with in-place oil of over 437.4 MMT. The Asset has already produced approx 65 MMT of oil during its 50 year existence.

Activities and Equipment

Entire gamut of Exploration and Production activities of Asset primarily involve

geological studies, well logging, well completion, reservoir studies and laboratory

services as exploration activities, drilling of oil and gas wells, casing and

cementing of wells as drilling activities whereas processing of the crude oil in

production installations and subsequent transportation of processed crude oil and

gas to the customer along with well stimulation operations and well maintenance

jobs, work over and wire line operations, artificial lift, gas compression in gas

compression stations, pressure maintenance operations and process plant

maintenance etc. fall in fold of production activities.

Crude oil and natural gas resources are found in subsurface reservoirs. The

drilling of oil and gas wells is necessary to produce these hydrocarbons. Drilling

through the earth's crust is accomplished by using rigs to handle pipes to for

drilling the well bore to allow fluids to flow to the surface for processing at

production facilities. Thus, the purpose of oil /gas well drilling is to exploit oil and

gas deposits in the reservoir from the surface. Rotary drilling is the most

common process for this purpose. Major equipment used in drillings are- DG sets

and PCR(Power control room),Mud pumps, Mud circulation system, Blow out

prevention equipment, Choke and kill manifold,kelly,kelly hose, rotary table,

safety devices like chronometric and floriated devices, Escape line, cat head and

cat lines, tongs and handling tools etc. Drilling of oil well is carried out through

drilling rigs operating with rotary drilling technology in conformance to

geotechnical order wherein casing policy and drilling parameters at various

depths are explicitly defined.

Processing of crude oil produced as a result of drilling and completion of well is

carried out in production installation named as Group gathering stations/Central

tank forms. Processing of crude oil is primarily meant to knock out the basic

sediments and water co produced with crude oil and gas so as to generate crude

oil and gas acceptable to the customers. Crude oil processing is comprised of a

series of processes namely well manifold, bath heater, separator, heater treater,

storage tanks and dispatch facilities. The well manifolds regulate the flow of

crude and gas to bath heater where it is preheated to maintain its fluidity. From

bath heater crude and gas are subjected to separator wherein phase separation

(Crude, gas and water) takes place. From here crude oil is subjected to heater

treater.Prior to heater treaters dosing of demulsifier, a surface active chemical is

done. This ensures chemical de-emulsification of crude oil which is an emulsion.

In heater treater heating provision and electrical chamber with very high

potential difference are there which ensures heating and electrical de-

emulsification. Thus, processing of crude oil emulsion is done through a

combination of chemical, heating and electrical de-emulsification. This

demulsified crude is collected in storage tanks from where it is transported

through trunk lines to de Salter plant where fine tuning of crude is done by way

of further removal of emulsified water and inherent salt content. From here the

crude is dispatched to refinery. Gas separated during the phase separation is

compressed to transport to customer.

Other important allied activities are work over and wire line operations and

logging of wells. Work over stimulation and wire line operation means to perform

one or more of a variety of remedial operations on a producing well or ceased oil

well with the intention of retaining and /or increasing production. Various such

operations are scrapping, plugging back, squeeze cementing, shooting, artificial

lift installation, fishing, stimulation etc. A work over rig may be used for the

purpose depending upon the total expected load to be handled. Logging

activities are related with the collection of information like characteristic of the

formation, location and thickness of oil sand, type and nature of hydrocarbon

deposits etc. pertaining to the well.

Raw material used

Exploration and production of hydrocarbon is not a raw material intensive

business, howecver some chemicals are used in processing of crude oil and

natural gas as well as in preparation of chemical drilling fluid and brine for

drilling and work over activities.

Demulsifires which are used for de- emulsification of crude oil are largely poly

phosphonates.

For preparation of chemical drilling fluid mostly oil based base chemicals like

bentonite are used which is supported with a range of chemicals for the purpose

of modification of rheological properties, water loss control and density etc.

The major activities of upstream Exploration and production activities of Ahmadabad Asset are to produce and market crude oil and natural gas. The major customer of Asset are Koyali refinery, Gas authority of India limited and approx 25 local gas consumers.

Approximately 1300 oil and Gas wells flow to nearby GGS cum CTF where it is treated for processing to separate crude oil ,gas and free water and further to reduce basic sediments and water content of crude oil.. to Desalter plant to finally processing it to the requirements of refiners. Desalter plant is processing the crude oil from Ahmadabad and Mehsana asset has six huge storage tanks each of 30000 M3 capacity. From here the processed crude oil is transported to Koyali Refinery through trunk line.. The key support services like Finance, Administration, Fire & Security, Logistics, Well Logging, Cementing & Medical Services etc. are provided centrally by Ahmedabad Asset to all the Installations including.

Project Description and Project Benefits

4 Wells are planned to be drilled during XII th plan ( 2013-17) in Karan nagar field of Ahmedabad. ONGC is oil major and strives to continually hike the production of hydrocarbon to meet the ever growing national demand. To accomplish the soaring need of hydrocarbon Ahmedabad asset of ONGC plans to drill oil wells in next five years to optimize the hydrocarbon production from the existing proven oil fields. In Ahmedabad asset, about 47.59 MMt reserve is available for exploitation in different fields. Development drilling is one of the main activities to exploit the available reserves.

Project cost Vs Expected gain

Project Cost Cost of drilling a vertical well : Rs.4.0 crores approx. Total Nos. of vertical wells planned to be drilled during next five years = 406( including 268 additional Wells in Gamij Field) Cost of drilling 390 vertical wells @ 4.0 crore = 1560.00 crores approx. Drilling of 16 horizontal well@ Rs. 12 crore per well = 192 crores. Total cost of drilling of 406 wells = 1752 Crores approx.

Project Benefits

Oil Production from additional 268 Nos of wells to be drilled in Gamij Area = 2045

m3/d

Gas Production from additional 268 Nos of wells to be drilled in Gamij Area =

155482 m3/d

Employment Opportunities:-The drilling process will involve a

number of skilled and unskilled workers. There is possibility that local people will be engaged for the purpose and hence improve the existing

employment scenario of the region. The drill site construction would be done largely by employing local labour. At each drill site

construction local employment will be generated.

Development of area and impact on local economy: - The

villagers would be benefited as the approach roads to drilling sites will be upgraded and would ensure better accessibility to villages. Large

number of workers residing in site area will obviously give rise to developmental and commercial activities in that region.

Improvement in the road condition:- The villagers would be

benefited through the project, since during the site preparatory phase the existing earthen road to be used as the approach road to

the drilling site, would be upgraded and would thereby ensure better accessibility to the villages

Brief of Drilling Operations

In order to produce the hydrocarbons from the reservoir, drilling of the

well is carried out. Generally wells are designed based on the number of parameters like of the depth of well, type of reservoir, reservoir

pressure and temperature profile, potential of reservoir etc. Based on all these information casing policy of the well is decided. In

Ahmedabad Asset, depth of wells varies from 800 to 2000 meters and

these wells are completed with 2 or 3 casing policy. The 1st casing is lowered up to the target depth of 300-350 meters,

mainly to isolate the sweet water zone and provide support for well- head, casing and X-mas tree. In three casing wells, intermediate

casing is lowered in the depth zone of 1200 to 1700 meters or more depending upon the geological details of the fields. The production

casing is lowered up to the target depth to accommodate the tubing meant for oil production.

The drilling of well is mainly classified in three segments namely- a) Rig building –

This includes preparing the Rig by assembling the equipment for drilling operations once it is dismantled and transported from the

previous location to new location . b) Drilling Operation-

Well is drilled, cased with suitable number of casing strings at pre decided intervals and subsequently cemented in accordance to the

GTO.

c) Production Testing- The most probable zones of reservoir are tested for the presence of

hydrocarbons and if found viable, production from the well is taken by lowering the production string in the finally lowered production

casing.

Consumption of drilling fluid chemicals:-

Following seven mud systems have been adopted for drilling the wells. i) KCL-PHPA-Polymer mud system

ii) Choline Chloride-PHPA- Polymer mud system iii) Non damaging drilling fluid( NDDF)

iv) LIG- CMC Mud system v) KOH –K- Lignite mud system

vi) Deflocculant- PAC mud system

vii) CL-CLS Mud System

Water consumption:

Water consumption per well: 1979 KL

Water consumption per well: 1979 KL

Power Generation Electric power generation is done through DG sets running on diesel for providing

auxiliary power to all drilling equipment

Energy Finger print with reference to HSD consumption Drilling Rig HSD Consumption (KL) Lubricants (KL) F-3050-II (R2) 1026.81 15.66

Rig CW #1 146.99 16.149

Rig CW #2 342.42 18.63

Rig CW #3 490.93 19.59

Rig CW #4 631.50 27.48

Rig CW #8 541.11 17.66

.

Solid removal Each drilling rig is equipped with solid removal facilities like shale shakers with varied

mesh size screen,desander and de silters to remove even minute size of cuttings. Each

type of cutting is collected in specified enclosures.

Drill cutting ,unusable drilling fluid disposal and effluent

treatment

Recently pits with impervious linings are being planned to store drill cutting and unused

drilling fluid for the purpose of stipulated disposal of cuttings and unused drilling fluid.

Proposal in this regard is under approval of asset management.

For the purpose of effluent management a pit system is prepared so as to provide

sufficient time for suspended particles to settle down, termination of emulsified oil ,if any

which is scrummed. The fair quantity of thus, treated effluent is reused for preparation of

drilling fluid, cleaning of channels and making up of the drilling fluid.

Logistics Large numbers of heavy vehicles like trailors, trucks, cementing units, logging units,

cranes, tractors, buses & jeeps needs to be deployed to transport equipment, manpower

and to carry out other specialized jobs as and when required.