Environmental Impact Assessment (EIA) - Pollution Control

INDIAN OIL CORPORATION LIMITED

Draft Report on

Environmental Impact Assessment (EIA) For

Implementation of BGR INDMAX project associated with

BGR crude processing capacity enhancement from 2.35 to 2.7 MMTPA,

DHDT capacity enhancement from 1.2 to 1.8 MMTPA,

CRU-MSQ revamp & Implementation of SDS unit

At

Tehsil Sidli (PT-II), PO.Dhaligaon, District: Chirang, Assam.

ABC TECHNO LABS INDIA PVT. LTD. AN ISO ISO 9001:2008, ISO14001:2004 & OHSAS 18001:2007 certified

Environmental Engineering and Consultancy Organization

(NABL Accredited & MoEF Recognised Environment Laboratory)

QCI NABET Accredited for Sector 5F (Certificate No. NABET / EIA / 1316 / RA001)

Corporate Office: No.2, 2

nd Street, Thangam Colony, Anna Nagar West, Chennai – 600040.

Tamil Nadu, India.

Tel: 044 – 26161123 / 24 / 25

Mumbai Office:

A-355, Balaji Bhavan, Plot No. 42 A, Sector 11, CBD Belapur, Navi Mumbai – 400614. Maharashtra, India

Tel: 022 27580044

Draft EIA for Implementation of INDMAX project associated with crude processing capacity enhancement from 2.35 to 2.7 MMTPA, DHDT capacity enhancement from 1.2 to 1.8 MMTPA, CRU-MSQ revamp &

implementation of SDS unit by M/s IOCL, Bongaigaon Refinery at Dhaligaon, Dist: Chirang (BTAD), Assam

ABC Techno Labs India Pvt. Ltd. 2

Content EXECUTIVE SUMMARY ....................................................................................................................... 9

CHAPTER 1: INTRODUCTION ............................................................................................................ 36

1.1 Background .................................................................................................................... 36

1.2 Need of the Expansion of Bongaigaon refinery ................................................................ 36

1.3 Need of EIA ..................................................................................................................... 37

1.4 Terms of Reference (TOR) ............................................................................................... 37

1.5 Approach and Methodology ........................................................................................... 37

1.6 Environmental Settings ................................................................................................... 39

1.6.1 Location Details of the Site ............................................................................................ 39

1.6.2 Accessibility to Plant Site .............................................................................................. 40

1.7 EIA Report Presentation .................................................................................................. 41

Figure 1.1: Index Map of BGR INDMAX project .................................................................... 41

CHAPTER 2 ...................................................................................................................................... 44

PROJECT DESCRIPTION .................................................................................................................... 44

2.1 Introduction: .................................................................................................................. 44

2.2 Needs of Capacity Enhancement ..................................................................................... 44

2.3 Project Location .............................................................................................................. 45

Figure 2.1: Location of Bongaigaon refinery at Dhaligaon, Assam on Google Satellite Image 46

Figure 2.2: Plot Plan of Bongaigaon Refinery ...................................................................... 47

2.4 Manufacturing Process Details ........................................................................................ 48

Table no.2.1: Specification of Diesel ................................................................................ 49

2.5 Power Requirement: ...................................................................................................... 56

Table no. 2.2: Power Requirement .................................................................................. 56

2.6 Water Requirement and Waste Water Generation ......................................................... 56

2.7 Environmental mitigation measures of the project: ........................................................ 56

Table no.2.3: Environmental mitigation measures .......................................................... 56




2.8 Project Cost: ................................................................................................................... 58

Table no. 2.4: Project Cost .............................................................................................. 58

CHAPTER 3 ...................................................................................................................................... 60

DESCRIPTION OF ENVIRONMENT ..................................................................................................... 60

3.1 Introduction ................................................................................................................... 60

3.2 Topography and Physiography ........................................................................................ 60

3.3 Geology .......................................................................................................................... 60

3.4 Soil Characteristics .......................................................................................................... 61

Figure 3.1: Soil sampling locations ....................................................................................... 62

Table 3.1: Details of Soil Sampling Locations ................................................................... 62

Table 3.1: Soil Characteristics in the Study Area .............................................................. 62

3.5 Water Resources and Water Quality ............................................................................... 63

3.5.1 Water Resources ...................................................................................................... 63

3.5.2 Surface Water Resources .......................................................................................... 63

3.5.3 Ground Water Resources.......................................................................................... 63

3.5.4 Ground and Surface Water Quality ........................................................................... 64

Figure 3.2: water sampling locations ................................................................................... 64

Table 3.3: Indian Standard Specification for Drinking Water ............................................ 66

Table 3.4: Ground Water Quality in the Study Area ......................................................... 70

Parameters...................................................................................................................................... 70

Table 3.5: Analysis Results of Aie River Water ................................................................. 72

3.6 Climatology and Meteorology ......................................................................................... 72

3.6.1 Introduction ............................................................................................................. 72

3.6.2 Climatology .................................................................................................................... 73

3.6.3 Climatological Data ......................................................................................................... 73

Table 3.10: Summary of Micro meteorological Conditions near the site .......................... 75

3.6.4 Micro Meteorological Data for the Site ..................................................................... 80




3.7 Ambient Air Quality ........................................................................................................ 80

3.7.1 Introduction ............................................................................................................. 80

3.7.2 Methodology of Monitoring and Analysis ................................................................. 81

3.7.3 Sampling and Analytical Techniques ......................................................................... 82

Table 3.11: Techniques Used For Ambient Air Quality Monitoring ................................... 82

3.7.4 Ambient Air Quality Monitoring Locations ................................................................ 83

3.7.5 National Ambient Air Quality Standards.................................................................... 83

3.7.6 Results of Ambient Air Quality Monitoring ................................................................ 84

3.7.7 Ambient Air Quality Status ....................................................................................... 85

Table 3.12: National Ambient Air Quality Standards ........................................................ 85

Table 3.13 : Ambient Air Quality at Project Site (AAQM1) ............................................... 87

Table 3.14 : Ambient Air Quality (AAQM2) ...................................................................... 88


Table 3.16: Ambient Air Quality (AAQM4) ....................................................................... 90


Table 3.18 : Ambient Air Quality (AAQ6) ......................................................................... 92



3.7.8 Stack Emissions Monitoring From DG Set Stack......................................................... 95

Table 3.20: Stack Emission Monitoring for DG Sets.......................................................... 95

3.8 Ambient Noise Levels...................................................................................................... 95

3.8.1 Introduction ............................................................................................................. 95

3.8.2 Methodology ............................................................................................................ 95

3.8.3 Equivalent Sound Pressure Level (Leq) ...................................................................... 96

Table 3.21: Ambient Standards in Respect of Noise ......................................................... 97

Table 3.22 - Day and Night Time Leq in the Area ............................................................. 97

3.9 Land Use Pattern ............................................................................................................ 98




Table 4. 14 Land Use/Land Cover Area Statistics in Area of 10 Km Radius around BGR .. 103

3.10 Biological Environment ................................................................................................. 104

3.10.1 Introduction ............................................................................................................... 104

3.10.2 Flora Found in the study area .................................................................................. 104

Table 3.24: List of Trees, Shrubs, and Climbers found in the Study Area ........................ 104

3.10.3 Wildlife in the Study Area ....................................................................................... 107

3.10.4 Environmental Sensitive Area .................................................................................. 109

3.11 Socio-Economic Environment ....................................................................................... 110

3.11.1 Social Profile of the Project District ......................................................................... 111

Table 3.25: Demographic and Occupational Details ....................................................... 114

3.11.2 Demographic Details of Settlements in the Study Area ........................................... 118

3.11 Traffic Analysis .............................................................................................................. 119

CHAPTER 4 .................................................................................................................................... 123

ANTICIPATED ENVIRONMENTAL IMPACTS & MITIGATION MEASURES ........................................... 123

4.1 Introduction ................................................................................................................. 123

4.2 Physical Environment.................................................................................................... 123

4.2.1 Soil ......................................................................................................................... 123

4.2.2 Water Quality ......................................................................................................... 125

4.2.4 Noise ...................................................................................................................... 126

Table 4.1: Anticipated Noise Levels from Various Sources ............................................. 126

Table 4.2: Noise Level at Various Distances ................................................................... 128

Figure no.4.1: Noise levels during construction phase ....................................................... 129

4.2.5 Terrestrial Ecology .................................................................................................. 129

4.3 Demographic, Land Use And Socio-economic Environment ........................................... 129

4.3.1 Demographic .......................................................................................................... 129

4.3.2 Socio-economic ...................................................................................................... 130

4.3.4 Sustainable Development and Environmental Protection ....................................... 130




Chapter 5 ...................................................................................................................................... 133

Alternative Analysis ....................................................................................................................... 133

5.1 Introduction ................................................................................................................. 133

5.2 Alternative Technology ................................................................................................. 133

5.3 Alternative Site .................................................................................................................... 134

5.4 Alternatives for Storage ................................................................................................ 135

5.5 Alternative for risk reduction at petrochemical refinery: ............................................... 135

CHAPTER 6 .................................................................................................................................... 138

ENVIRONMENTAL MONITORING PLAN .......................................................................................... 138

6.1 Introduction ................................................................................................................. 138

6.2 Environmental Monitoring Schedules ........................................................................... 138

6.2.1 Ambient Air Quality (AAQ) Monitoring ................................................................... 139

6.2.2 Water Quality Monitoring....................................................................................... 139

6.2.3 Noise Levels Monitoring ......................................................................................... 139

6.4 Environmental Monitoring Plan .................................................................................... 139

Table 6.1: Environmental Monitoring Plan for BPRL Plant of IOCL ................................. 140

6.5 Health, Safety & Environmental Management Cell ....................................................... 142

Table 6.2: Responsibilities of Personnel of the HSE Department .................................... 142

6.6 Statutory Returns and Compliance Reports ................................................................... 142

CHAPTER 7 .................................................................................................................................... 145

RISK ASSESSMENT & HAZARD IDENTIFICATION .............................................................................. 145

7.1 Introduction ................................................................................................................. 145

7.2 Rapid Risk Assessment at Bongaigaon Refinery Plant .................................................... 147

7.3 Objective and Scope of Study ........................................................................................ 147

7.4 General: ........................................................................................................................ 147

7.5.7 ESTABLISHING OF CENTRAL CRISIS CONTROL ROOM (CCR) ..................................... 171

CHAPTER 8 .................................................................................................................................... 178




PROJECT BENEFITS ........................................................................................................................ 178

8.1 Project Benefits ............................................................................................................ 178

8.2 Direct Benefits .............................................................................................................. 178

8.3 Improvement in the Social Infrastructure ...................................................................... 178

8.4 Reduction of Emissions ................................................................................................. 178

CHAPTER 9 .................................................................................................................................... 180

ENVIRONMENTAL MANAGEMENT PLAN ........................................................................................ 180

9.1 SAFETY, HEALTH & ENVIRONMENTAL POLICY ...................................................................... 180

9.2 DESIGN PHASE ..................................................................................................................... 181

9.2.1 AIR ENVIRONMENT....................................................................................................... 181

9.2.2 WATER ENVIRONMENT ................................................................................................ 181

9.2.5 GREEN BELT DEVELOPMENT ......................................................................................... 182

Table no.6.1: The details of land cover and green cover ................................................ 182

9.3 CONSTRUCTION PHASE ........................................................................................................ 183

9.3.1 AIR ENVIRONMENT....................................................................................................... 183

9.3.2 NOISE ENVIRONMENT .................................................................................................. 183

9.3.3 WATER ENVIRONMENT ................................................................................................ 183

9.3.4 LAND ENVIRONMENT ................................................................................................... 183

9.3.5 CONSERVATION OF GREENERY ..................................................................................... 183

9.3.6 SAFETY MEASURES ....................................................................................................... 183

9.3.7 SOCIO-ECONOMIC ENVIRONMENT ............................................................................... 184

9.4 OPERATIONAL PHASE .......................................................................................................... 184

9.4.1 AIR ENVIRONMENT....................................................................................................... 184

9.5 END-OF-PIPE (EOP) TREATMENT .......................................................................................... 185

9.5.1 EFFLUENT SEGREGATION AND COLLECTION PHILOSOPHY ............................................. 185

9.6.1 Noise abatement measures .......................................................................................... 188

9.7 GROUND WATER ................................................................................................................. 188




9.8 LAND ENVIRONMENT .......................................................................................................... 188

9.8.1 IN-PLANT CONTROL MEASURES .................................................................................... 188

9.8.2 SOLID WASTE DISPOSAL ............................................................................................... 188

9.9 SOIL QUALITY MONITORING ................................................................................................ 190

9.10 BIOLOGICAL ENVIRONMENT .............................................................................................. 190

9.11 ENVIRONMENTAL AUDIT ................................................................................................... 190

9.12 ENVIRONMENTAL CELL AND MANAGEMENT ..................................................................... 191

9.13 SOCIO-ECONOMIC ENVIRONMENT .................................................................................... 191

CHAPTER 10 .................................................................................................................................. 193

DISCLOSURE OF CONSULTANTS ..................................................................................................... 193

10.1 Introduction ................................................................................................................. 193

10.2 The Consultant: ABC Techno Labs ................................................................................. 193

10.3 Services of ABC Techno Labs India Private Limited ........................................................ 193

10.3.1 Environmental Services .............................................................................................. 194

10.3.2 Turnkey Projects ......................................................................................................... 194

10.3.3 Other Services ............................................................................................................ 194

10.3.4 Laboratory Services .................................................................................................... 194

10.4 Sectors Accredited by NABET (QCI) ............................................................................... 194

10.5 Study Team for EIA Study .............................................................................................. 195




EXECUTIVE SUMMARY 1. INTRODUCTION

Bongaigaon Refinery (BGR) is the eighth operating refinery of IOCL, formed upon the amalgamation

of Bongaigaon Refinery & Petrochemicals Limited (BRPL) with Indian Oil Corporation Ltd. (IOCL) on

March 25, 2009. Bongaigaon refinery is situated at Dhaligaon in Chirang district of Assam, 200 km

west of Guwahati.

Bongaigaon Refinery (erstwhile BRPL) was commissioned in year 1979 with crude processing

capacity of 1.00 Million Metric Ton Per Annum (MMTPA). The crude processing capacity was further

increased to 1.35 MMTPA in 1986. Presently, the Refinery has two Crude Distillation Units (CDU)

having total crude processing capacity of 2.35 MMTPA, two Delayed Coker Units (DCU) and a Coke

Calcination Unit (CCU). The refinery has implemented Diesel Hydrotreatment (DHDT) project and MS

Quality Improvement (MSQ) project in the year 2011. For the first time in India, technology

indigenously developed by M/s IOCL (R&D) and Engineers India Limited (EIL) was adopted for these

two projects.

As per the declaration of Government of India dated 6th Jan’16, it was proposed to implement BS-VI

grade fuel in the entire country w.e.f. 1st April 2020 i.e. by switching over directly from BS-IV grade

fuels to BS-VI grade fuel. Thus, it is imperative to upgrade the Refinery for the production of BS-VI

grade fuels by inducting suitable new units and revamp of exiting units

2. PROJECT DESCRIPTION

The location of project site is given in the Figure 1.

Draft EIA for Implementation of INDMAX project associated with crude processing capacity enhancement from 2.35 to 2.7 MMTPA, DHDT capacity

enhancement from 1.2 to 1.8 MMTPA, CRU-MSQ revamp & implementation of SDS unit by M/s IOCL, Bongaigaon Refinery at Dhaligaon, Dist: Chirang (BTAD),

Assam


Figure 1: Location Map of the project site



Assam


Figure 2: Satellite Image of the site

Draft EIA for Implementation of INDMAX project associated with crude processing capacity

enhancement from 2.35 to 2.7 MMTPA, DHDT capacity enhancement from 1.2 to 1.8 MMTPA, CRU-

MSQ revamp & implementation of SDS unit by M/s IOCL, Bongaigaon Refinery at Dhaligaon, Dist:

Chirang (BTAD), Assam


2.1 ENVIRONMENTAL SETTINGS OF THE SITE

Table 1 : Environmental Settings of the Project Site

Sl.

No. Particulars Details

1 Latitude 26°31’00.81"N

2 Longitude 90°31'53.85“E

3 Site Elevation above MSL 63 m

4 Topography The topography of the district represents mostly

plain lands

5 Present land use at the site Industrial use

6 Nearest National /State

highway, District

road/Approach road

NH 31C -0.7 km (Approx.)

7 Nearest railway station New Bongaigaon station

8 Nearest airport Lokopriya Gopinath Bordoloi International Airport,

Guwahati

9 Water body Lakes:

Nayachara Lake (Beel) -7.0km (Approx.)

Bhosamari Lake -9.2 km, (Approx.)

Paropota Lake -9.5 km, (Approx.)

Naodora Lake -9.2 km, (Approx.)

Kasorani Lake -9.2 km (Approx.)

Rivers :

River Aie -6.0 km, (Approx.)

River Tunia -4.0km (Approx.)

River Kujia -7.0 km (Approx.)

10 Archaeologically important

places

Not in 5 km radius from the project site

11 National parks / Wildlife

Sanctuaries

Not in 5 km radius from the project site

12 Reserved / Protected Forests Nakkati Reserved Forest- 7.5 km, (Approx.)

Kakoijana Reserved Forest- 9.5 km, (Approx.)

Bhumeswar Reserved Forest- 7.8 km (Approx.)

13 Seismicity Seismic zone –v

14 Defence Installations None

3. NEED FOR THE PROJECT

The present crude processing capacity of BGR is 2,350,000 TPA of Assam Crude Oil and Low

Sulphur Imported Crude Oil. In view of the Auto-Fuel Policy Vision 2025, the Refineries will

be required to supply fuels meeting the BS-IV specification fuels by 1st April 2017 and BS-

V/VI specification by 1st April, 2019. The BS-VI fuel will bring down the Nitrogen Oxide

emissions by 68% from diesel cars and by 25% from petrol engine cars. Cancer causing






particulate matter emissions from diesel engine cars will also come down by a phenomenal

80 %.

In order to meet the requirement of BS VI Fuel demand, following projects at BGR are

proposed for implementation.

• Crude processing capacity enhancement from 2.35 MMTPA to 2.7 MMTPA

• DHDT capacity enhancement from 1,200 TMTPA to 1,800 TMTPA to meet BS-VI

HSD specification.

• CRU-MSQ revamp to meet BS-VI MS specification.

• Selective Desulphurisation (SDS) Unit.

• INDMAX Project along with Indmax Gasoline De-Sulphurisation Unit.

3.1 Project Description

Table 2: Salient Features of the Project

Item

Description Details

Project

Proposal

CDU capacity enhancement from 2.35 to 2.7 MMTPA, DHDT revamp by 150%

through capacity enhancement of HGU by 25%, CRU revamp by 120% with new

NHT unit, MSQ catalyst change and implementation of INDMAX with SRU & Prime

G.

Location Mouza No.: Sidli Part II, Revenue survey no. 450, Dhaligaon, Dist. Chirang, Assam

Land

Requirement

& its break up

for land use

S.

No. Particulars

Existing

land area

(Sq. m.)

Proposed

Land Area for

Expansion

(Sq. m.)

Total Area

(Sq. m)

% of Total

Area

1 Plant Area 34,43,826 - 34,43,826 75.18%

2 Township 1,137,168 - 1,137,168 24.82%

TOTAL 45,80,994 - 45,80,994 100.0%

Man power

requirement

Construction phase: 5,430 nos.

Operation phase: 20 nos.

Power

requirement

& Source

DHDT: 300 KW

INDMAX FCC Unit: 3,620 KW

IGHDS: 255 KW

SDS Unit: 45 KW

Source : GTG, TG






Water

requirement

& Source of

supply

Sn Particulars Source Requirement

(m3

/hr) Remarks

1.

Raw water

for CDU-II,

DHDT,SDS

& CRU-

MSQ

- - No additional raw water required

2.

Raw

Water for

INDMAX

Ground

water 40

• Treated effluent water from TTP

will be reused in cooling tower

as make up

• Raw water requirement is for

service water only

Wastewater

generation,

treatment &

disposal

The plant has installed a 400 m3/hr capacity Tertiary Treatment Plant. The treated

effluent water will be reused as make up water for cooling tower and green belt

development.

Air Pollution

Sources and

Control

Measures

Source Air Pollution Control Measures

D.G. Sets used in case of

power failure

Adequate height of stack – 3 m from the

highest roof of establish as per CPCB

norms

Solid waste

generation &

Management

Very negligible only about 5 kg solid wastes will also be generated from office and

canteen. It will be handled by local bodies.

Project Cost Rs. 4185.4 Cr.

4. BASELINE ENVIRONMENTAL STATUS

4.1. Temperature

The winter season starts from December and continues till the end of February.

January is the coolest month. The mean daily maximum temperature during winter

season is 24.6 °C (in the month of December) and the mean daily minimum

temperature at 11.5 °C (in the month of December). 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 was

observed to be 31.5°C in the month of April and the minimum temperature at 15.5°C

in the month of March. The mean maximum temperature in the monsoon season

was observed to be 31.4°C in the month of June. By the end of August the day

temperatures increase slightly, with the mean maximum temperature at 31.7°C in

the month of September and the night temperature decreases with the mean

minimum temperatures at 9.8°C in the month of January. The min. and max






temperatures recorded in Bongaigaon Refinery (BGR) during the year 2015 were 90C

& 390C respectively.

4.2 Rainfall

The district receives heavy rainfall of 3219.1 mm in an average under the influence of

south west monsoon. In the year 2015, the max. daily rainfall in BGR was recorded at

326 mm. Humidity is high ranging up to 80-90 % during rainy season. In BGR, the

average humidity was recorded as 76.2% and the max. as 100% during the year 2015.

Parameter Post Monsoon Season

Temperature

Max (oC)

Min (oC)

32.9

5.1

Relative Humidity

Max (%)

Min (%)

76 %

64%

Wind Speed

Max (kmph)

Min (kmph)

Mean (kmph)

8.3

2.3

4.1

Calm Period (%) 32.1

Predominant Wind Flow Direction Towards E, ENE, NE directions

4.3 Ambient Air Quality

To study the baseline air quality scenario in the study area, six Ambient Air Quality

Monitoring (AAQM) stations were selected in the study area in different directions and at

different distances from the project site keeping in view of the guidelines of the Ministry of

Environment, Forest and Climate Change (MOEF&CC).

The baseline data of air environment was monitored for the below mentioned parameters:

• Particulate Matter (PM2.5);

• Particulate Matter (PM10);

• Sulphur dioxide (SO2);

• Di oxides of Nitrogen (NO2);

• Ozone (O3);

• Lead (Pb);

• Carbon Monoxide (CO);

• Ammonia (NH3);

• Benzene (C6H6);

• Benzo (a) Pyrene (BaP);

• Arsenic (As);

• Nickel (Ni),






4.4 Ambient Noise Level

Noise can be defined as an unwanted sound. It interferes with speech and hearing and is

intense enough to damage hearing or is otherwise annoying. The definition of noise as

unwanted sound implies that it has an adverse effect on human beings and their

environment. Noise can also disturb wildlife and ecological system.

To understand the noise environment in the study area, a noise survey was conducted using

Sound Level Meter 2031 manufactured by Cygnet Systems. Noise measurements were

carried out at the same location where ambient air quality was monitored. The 24-hourly

sound levels were measured at each location once during the study period.

4.5 Soil Quality

The proposed projects including Indmax may affect the existing land use pattern in the

study area by change in present land use and encouraging more entrepreneurs to go in for

the new industries in this region. This in turn may have further impact on the existing basic

infrastructure. Therefore the land environment background status in terms of the land use

pattern needs to be assessed.

In order to characterize the soil quality within the study area, soil samples have been

collected from nine different locations in the study area.

4.6 Ecology

The information of important flora and terrestrial animal groups such as birds, reptiles and

mammals were collected by trekking inhabiting area, along the road, nearby forest areas

and agricultural fields present in the impact zone. An inventory of the plants and animals

has been prepared separately for mammals, reptiles and birds.

4.7 Socio- Economic

Socio-economic environment in the vicinity of any ensuing project is affected by the mode

of change that is likely to occur due to the beneficial or adverse effects arising out of the

project activity. The impact of such change is dependent upon likely job opportunities

economic output immigration strain on the existing basic amenities and overall impact on

the quality of environment, which may impair the health status of the people living in that

geographical area.

The projection of such assessment calls for collection of the baseline and background

information about the socio-economic and demographic environment of the surrounding

areas of the proposed site. A study area comprising an area of 10 km radius around the

proposed project was chosen for studying the socio-economic characteristics

The study area is well connected by railway route linking NE region with the rest of the

country. Three National Highways pass through this district. Sericulture is one of the

important agro-based employment generating activities in this region. Climatic conditions

are favourable for encouraging sericulture crops like mulberry, Eri, Muga etc. Socio-

economic profile of all these villages in terms of demographic characteristics like population,






literacy, occupational structure, and basic infrastructure was collected with the help of

Survey of India toposheets and 2011 census data

5. PREDICTION OF IMPACTS AND ITS MITIGATION MEASURES:

5.1 Impacts on Air

During Construction Phase

During the expansion, revamp phase, Activities like cleaning, levelling, grading, construction,

metal cutting, and erection of equipments like Columns, Vessel Pumps will be carried out.

A certain amount of particulate matter will be generated by truck movements during the

construction phase. However, the suspended particulate matter in ambient air as a result of

construction activities may be relatively coarse and will be settled within a short distance.

Therefore, the impact will be restricted within the close vicinity of the construction activity

for short period of time.

During Operation Phase

• During operation there will be NOx, SOx stack emissions from INDMAX FCC

generator, IGHDS unit, CDU-II, DHDT unit, and CRU unit, plant after expansion, the

major SOx emissions from INDMAX unit will be controlled by installing SDS unit at

plant. All the Stack heights will be designed as per CPCB guidelines.

• Fugitive emissions of hydrocarbon may result from unloading hose, faulty bottling,

leaking cylinders and minor leaks. Gas leak detectors, and Floating roof storage tanks

will be provided at strategic locations to detect concentration of hydrocarbon in the

premises.

• DG sets installed at BGR plant, are operated occasionally in case of power failure and

these are not regular source of gaseous emissions.

• Tankers/trucks/vehicles have pollution under control (PUC) certificates. Regular

maintenance of Diesel tankers/trucks will be ensured.

Mitigation Measures

• Cordoning off construction area by tin sheets & garden net

• Dust suppression measures like water sprinkling as per requirement.

• Use of adequate PPEs by the working personnel.

5.2 Impacts on Water


During the construction phase the demand of drinking water and construction water will be

meet from existing source. Adequate drinking water, hygiene and sanitation facilities will be

provided to the workers

The construction phase may result in minor soil erosion from the plant site, as it will clear of

ground flora during plant erection. The run off from the construction site during rainfall may






cause some increase in the quantity of suspended solids and turbidity in the runoff in

natural drain. However, this impact will be of temporary nature and may not last as soon as

excavated soil established and construction debris is disposed off properly


Only 40 m3/hr of water will be required daily for the INDMAX unit. While the CDU-II, DHDT,

SDS & CRU-MSQ units will not require any additional water.

• BGR has installed Tertiary Treatment Plant to facilitate reuse of effluent water inside

the complex as cooling water and firewater makeup.

•

Total water consumption after expansion will be 370 Cum/day and entire quantity of

treated effluent will be used for cooling tower make up and irrigation purpose. Thus

achieving Zero discharge status

• Waste water from canteen at the Plant will be treated in oil and grease trap followed

by septic tank and soak pits

•

Mitigation Measures

• Excavation for foundations of structures/vessels will be carried out during dry

season.

• Construction debris will be collected and disposed properly on daily basis.

• Sanitary facilities for workers will be provided.

5.3 Impacts on Noise Environment


During construction phase, metal cutting, and erection of equipments like Columns, Vessel

Pumps, cold cutting, hammering, vehicle movement, Rotary etc can generate noise, DG sets

may be major sources of noise generation during construction phase. Relatively high noise

levels will be generated during construction phase.

Mitigation Measures

• Use of ear muff and ear plugs to workers working in high noise area.

• Acoustic enclosures are already fitted with DG sets.


Noise generation is expected from piling process and rotating machinery, equipments. The

other sources are pumps, compressor, and turbines. DG sets are to be operated only during

grid power failure.






Mitigation Measures

• Equipment specification and installation of acoustic enclosure with DG sets ensure

low level of noise generation.

• All the Diesel Tankers and trucks are essentially fitted with silencers to control noise

generation.

• Planting trees and developing and maintaining green belt area which works as noise

barrier.

• Quarterly Noise surveys are conducted and abnormalities are resolved.

Therefore, impact on noise levels of the study area due operations at the BGR plant will

be insignificant.

5.4 Impacts on Land and Ecological Environment

During construction phase, around 5,430 workers will be deployed, mostly from local area.

The construction activity of proposed plant will not displace any person.

During Operation of proposed Indmax plant, will require only 20 skilled workers for

operating and handling the plant. Therefore, large scale immigration will not take place and

the impact on demography of the area will be insignificant.

The construction and operation of the plant will have some beneficial impact due to

increase in incomes as local unskilled, semiskilled and skilled persons as they will gain some

direct and indirect employment In view of the small manpower and support facility

requirements, the beneficial impact likely to be marginal. However, this expansion and

revamping is going to impact positively on the production capacity of IOCL, thus by serving

larger markets and serving the Indian economy.

Since the immigration of work force during construction and operation of the proposed

expansion, revamping and implementation of new technologies at the plant will be likely to

be very small, the impact on facilities and cultural aspects are expected to be insignificant.

At the centre of the socio-economic impact lies the question of whether economic

development and growth can go hand in hand with environmental protection. The

expansion, revamping activity and implementation of new technologies at the BGR plant is

not likely to have any negative impact if, the proposed mitigation for environmental

management are implemented by the IOCL management. The proposed changes will have

definite beneficial impacts, even though marginal, on infrastructures facilities, gross

economic product, employment opportunities, socio-economic aspects of the area






6. ENVIRONMENTAL MONITORING PLAN

S. No Particulars Monitoring

Frequency

Duration of

Sampling

Important

Monitoring

Parameters

1 Ambient Air Quality Monitoring

a Project site Once in a 3 months

24 hour

continuously

except CO

PM10, PM2.5, SO2,

NOx and CO

2 Stack Monitoring

a DG set Once in a 3 months 30 min

SO2, NOx, SPM, Co,

CO2, Temperature,

Flow rate and

velocity of gas

3 Ambient Noise Level

a Near DG set Once in 3 months 8hr continuously

with 1hr interval Noise level (dB)

4 Ground / Drinking water Quality

a Ground water at

project site Once in 3 months Grab Sampling

Parameters

specified under ISO:

10500, 1993

5 Sewage Quality Monitoring

a ETP Inlet

Once in a week Grab Sampling

Physical, Chemical

and Biological

parameters

specified under IS:

2490:1982

b ETP Outlet

6 Soil Quality

a At the green belt

area Once in a year

Samples collected

from three

different depths

viz., 30cm, 60cm

and 100cm below

the surface.

Parameter for soil

quality: pH, texture,

electrical

conductivity,

organic matter,

nitrogen,

phosphate, calcium,

potassium and

magnesium.

7 Flora and Fauna Once in a year - Number of plants

and animal species

8 Health Regular Check ups -

All relevant

parameters

including HIV






7. ADDITIONAL STUDIES

Industrial plants deal with materials, which are generally hazardous in nature by virtue of

their intrinsic chemical properties or their temperature or pressure of operation or a

combination of these. Fire, explosion, hazardous release or a combination of these are the

hazards associated with industrial plants. These have resulted in the development of more

comprehensive, systematic and sophisticated methods of safety engineering such as hazard

analysis and risk assessment to improve upon the integrity, reliability and safety of industrial

plants.

The primary emphasis in safety engineering is to reduce risk to human life and environment.

The broad tools attempt to minimize the chances of accidents occurring. Yet, there always

exists, no matter how remote, that small probability of a major accident occurring. If the

accident involves highly hazardous materials in sufficient large quantities, the consequences

may be serious to the plant, to surrounding areas and the populations therein.

Risk Assessment & Hazard Identification

Risk is defined as the unwanted consequences of a particular activity in relation to the

likelihood that this may occur. Risk assessment thus comprises of two variables, magnitude

of consequences and the probability of occurrence of accident.

The first step in risk assessment is identification of hazards. Hazard is defined as a physical

or chemical condition with the potential of accident which can cause damage to people,

property or the environment. Hazards are identified by careful review of plant operation

and nature of materials used. The various scenarios by which an accident can occur are then

determined, concurrently study of both probability and the consequences of an accident is

carried out and finally risk assessment is made. If this risk is acceptable then the study is

complete. If the risk is unacceptable then the system must be modified and the procedure is

restarted.

Scope of Risk Analysis

The scope of risk analysis study includes:

• Identify potential hazard sections of the plant, which are likely to cause damage to

the plant, operating staff and the surrounding communities in case of any accident

due to the proposed plant facilities.

• Assess overall damage potential of the hazardous events in relation to main plant

and environment.

• Assessment of total individual risk.

• Recommended emergency preparedness plan to mitigate the effects of any accident.






Risk Analysis

Risk Analysis of any plant / installation handling hazardous materials includes:

(a) Hazard Identification

• Identify potentially hazardous materials that can cause loss of human life/injury, loss

of properties and deteriorate the environment due to loss of containment.

• Identify potential scenarios, which can cause loss of containment and consequent

hazards like fire, explosion and toxicity.

(b) Consequence Analysis

• Analysis of magnitude of consequences of different potential hazard scenarios and

their effect zones.

• Consequence analysis is a measure of potential hazards and is important for taking

precautionary measures for risk reduction as for well as mitigation of effect in case

of such accidents happening.

•

This report has been prepared by applying the standard techniques of risk assessment and

the information provided by IOCL. Based on the Risk Assessment, Disaster Management

Plan (DMP) has been prepared.

8. PROJECT BENEFITS

Direct Benefits

The expansion, revamping, installation of INDMAX will aid in manufacturing and

I. Eliminating the production demand of Black Oil and Naphtha.

II. It will maximize the production of LPG.

III. The project will help to manufacture High Speed Diesel (BS-VI).

IV. High Speed Diesel (HSD) conforming to manufacturing specifications of BS-VI

• Availability of LPG will discourage deforestation and reduce the use of fire wood

& fossil fuels.

• Improve the quality of life of women engaged in household activities specially in

cooking.

Improvement in the Social Infrastructure

The expansion of Plant will create opportunities for direct and indirect employment in the

area. This will initiate local economic growth and thereby the potential to enhance quality of

life of the local communities. Local population will get benefited due to availability of safer

fuels.






Reduction of Emissions

The BS-VI will bring down the Nitrogen Oxide emissions from diesel cars by 68 % and 25%

from petrol engine cars. Cancer causing particulate matter emissions from diesel engine cars

will also come down by a phenomenal 80 %. Besides, the project would also improve the

smoke point of the kerosene stream from the Assam. It will, therefore, help in maintaining

cleaner environment due to reduction in emissions.

9. ENVIRONMENT MANAGEMENT PLAN

During operational phase, the area of concern will be stack emissions, liquid effluent and

intermittent disposal of spent catalyst (solid waste) from the proposed plant. During

operation there will be stack emissions from INDMAX FCC generator, IGHDS unit, CDU-II,

DHDT unit, and CRU unit, plant after expansion.

The Environmental Management Plan (EMP) for the proposed projects has to ensure that

the residual environmental impacts are minimized by adopting best possible economically

viable techniques. The EMP also has to ascertain compliance with all statutory conditions as

per No Objection Certificate (NOC) from Pollution Control Board Assam and Ministry of

Environment & Forests.

A comprehensive plan has been worked out keeping in view these requirements. The plan

encompasses the mitigation in three stages i.e. design, construction and operation of the

plant.

The Health Safety and Environmental Management at BGR is carried out by Deputy General

Manager (HSE). The DGM (HSE) reports to GM (TS & HSE). The DGM is assisted by Chief

Manager and officers etc.

10. CONCLUSION

Based on the environmental assessment, all possible environment aspects have been

adequately assessed and necessary control measures have been formulated to meet with

statutory requirements, in the preparation of the EIA-EMP. In view of the Auto-Fuel Policy

Vision 2025, the Refineries will be required to supply fuels meeting the BS-IV specification

fuels by 1st April 2017 and BS-V/VI specification by 1st April, 2019. The BS-VI will bring down

the Nitrogen Oxide emissions from diesel cars by 68 % and by 25% from petrol engine cars.

Cancer causing particulate matter emissions from diesel engine cars will also come down by

a phenomenal 80 %.

Considering that the proposed project of Bongaigaon Refinery will contribute in reducing

the pollution and help in environment protection for the cause of society, an Environmental

Clearance may be accorded for the proposed project.






4(a): STANDARD TERMS OF REFERENCE FOR CONDUCTING ENVIRONMENT IMPACT

ASSESSMENT STUDY FOR PETROLEUM REFINING INDUSTRIES PROJECTS AND

INFORMATION TO BE INCLUDED IN EIA/EMP REPORT

Sr.

no.

Terms of Reference Compliance

1. Executive Summary Attached with the EIA Report.

2. Introduction

Details of the EIA Consultant including NABET

accreditation

Refer chapter 10 Section 10.2 and 10.4 of

the EIA Report.

(i) Information about the project proponent. Refer chapter 1 Section 1.1 of the EIA report

(ii) Importance and benefits of the project Refer chapter 1 section 1.2 and chapter 8 of

the EIA report.

3. Project Description

(i) Cost of the project and time of completion Refer to chapter 2, section 2.6 of the EIA

report.

(ii) Products with capacities for the proposed

project

Refer to chapter 2 of the EIA report.

(iii) If expansion project, details of existing products

with capacities and whether adequate land is

available for expansion, reference of earlier EC if

any

BGR has adequate land, The expansion and

modernisation will take place in the plant

premises.

It is a Expansion, Modernisation, Revamping

and implementation of new technology for

the project. The current capacity of refinery

plant is:

CDU Capacity 2.35 MMTPA,

DHDT Capacity 1.2 MMTPA,

CRU - MSQ 160 TMTPA

New Proposed changes are increasing

capacity revamping manufacturing units and

implementation of new technologies:

CDU Capacity 2.7 MMTPA,

DHDT Capacity 1.8 MMTPA,

CRU - MSQ 200 TMTPA (Revamping)

INDMAX technology implementation along

with gasoline desulphurisation technology.

Selective De- Sulphurisation technology

Installation.

Ministry of Environment & Forests (MoEF)






has granted environmental clearance to

Bongaigaon Refinery vide letter no. J-

11011/9/2008/- IA II (I) dated 2nd

September, 2008 for INDMAX Project.

(iv) List of raw materials required and their source

along with mode of transportation

Refer to chapter 2 of the EIA report

(v) Other chemicals and materials required with

quantities and storage capacities


(vi) Details of Emission, effluent, hazardous waste

generation and their management

Refer to chapter 2, section 2.5 of the EIA

report

(vii) Requirement of water, power, with source of

supply, status of approval, water balance diagram,

man-power requirement (regular and contract)


(viii) Process description along with major

equipments and machineries, process flow sheet

(quantitative) from raw material to products to be

provided


(ix) Hazard identification and details of proposed

safety systems


(x) Expansion/ modernization proposals

a) Copy of all the Environmental Clearances

including Amendments thereto obtained for

the project from MoEF & CC/SEIAA shall be

attached as an Annexure. A certified copy of

the latest Monitoring report of the regional

office of the Ministry of Environment and

Forests as per circular dated 30th May, 2012

on the status of compliance of conditions

stipulated in all the existing environmental

clearances including Amendments shall be

provided. In addition, Status of compliance of

Consent to Operate for the ongoing existing

operation of the project from SPCB shall be

attached with the EIA-EMP report

Attached as Annexure-X

b) In case the existing project has not obtained

Environmental Clearance, reasons for not

taking EC under the provisions of the EIA

notification 1994 and/or EIA notification 2006

shall be provided. Copies of Consent to

Establish/ no objection certificate and

Consent to Operate (in case of units operating

prior to EIA notification 2006, CTE and CTO of

FY 2005-2006 obtained from the SPCB shall

be submitted. Further, compliance report to

Ministry of Environment & Forests (MoEF)

has granted environmental clearance to

Bongaigaon Refinery vide letter no. J-

11011/9/2008/- IA II (I) dated 2nd

September, 2008 for INDMAX Project






the conditions of consents from the SPCB

shall be submitted.

4. Site details

(i) Location of the project site covering village,

Taluka/Tehsil, District and State, Justification for

selecting the site, whether other sites were

considered.

Refer to chapter 1, Fig.1.2 and 1.3 of the EIA

report

(ii) A topo-sheet of the study area of radius of 10

km and site location on 1:50,000/1:25,000 scale on

A3/A2 sheet.(including all eco-sensitive area and

environmentally sensitive places)

Refer chapter 2 of the EIA report.

(iii) Details w.r.t options analysis for selection of

site


(iv) Co- ordinates (lat-long) of all four corners of

the site


(v) Google map-Earth downloaded of the project

site


(vi) Layout maps indicating existing units as well as

proposed unit indicating storage area, plant area,

greenbelt area, utilities etc. If located within an

Industrial area/Estate/Complex, Layout of Industrial

Area indicating location of unit within the Industrial

Area/Estate


(vii) Photographs of the proposed and existing (if

applicable) plant site. If existing, show photographs

of plantation/greenbelt, in particular


(viii) Land-use break-up of total land of the project

site (identified and acquired), government/private-

agricultural, forest, wasteland, water bodies,

settlements, etc shall be included.(not required for

industrial area)

Refer chapter 4, section 4.3.2 of the EIA

report.

(ix) A list of major industries with name and type

within study area (10 km) shall be incorporated.

Land use details of the study area

There is no major industry within 10 km

except NF Railway , Bongaigaon

(x) Geological features and geo-hydrological status

of the study area shall be included


(xi) Details of drainage of the project upto 5 km

radius of study area. If the site is within 1 km radius

of any major river, peak and lean season river

discharge as well as flood occurrence frequency

based on peak rainfall data of the past 30 years.

Details of flood level of the project site and

maximum flood level of the river shall be

provided.(mega green field projects)

Refer chapter 3, section 3.2 of the EIA

report.






(xii) Status of acquisition of land. If acquisition is not

complete, stage of the acquisition process and

expected time of complete possession of the land.

The project site is situated on the land

owned by IOCL

(xiii) R & R details in respect of land in line with

state Government policy

The project is proposed on IOCL owned land.

6. Environmental Status

(i) Determination of atmospheric inversion level at

the project site and site-specific micro-

meteorological data using temperature, relative

humidity, hourly wind speed and direction and

rainfall


(ii) AAQ data (except monsoon) at 8 locations for

PM10, PM2.5, SO2, NOX, CO and other parameters

relevant to the project shall be collected. The

monitoring stations shall be based on CPCB

guidelines and taking into account the pre-

dominant wind direction, population zone and

sensitive receptors including reserved forests.


report.

(iii) Raw data of all AAQ measurement for 12 weeks

of all stations as per frequency given in the NAQQM

Notification of Nov.2009 along with min.-max.,

average and 98 % values for each of the AAQ

parameters from data of all AAQ stations should be

provided as an annexure to the EIA report.


report.

(iv) Surface water quality of nearby River (100

upstream and downstream of discharge point) and

other surface drains at eight locations as per

CPCB/MoEF & CC guidelines.


report.

(v) Whether the site falls near to polluted stretch of

river identified by the CPCB/MoEF & CC, if yes give

details.

No

(vi) Ground water monitoring at minimum at 8

locations shall be included.

Refer chapter 3, section 3.5 of the EIA report

(vii) Noise levels monitoring at 8 locations within

the study area

Refer chapter 3, section 3.8 of the EIA report

(viii) Soil Characteristic as per CPCB guidelines. Refer chapter 3, section 3.4 of the EIA report

(ix) Traffic study of the area, type of vehicles,

frequency of vehicles for transportation of

materials, additional traffic due to proposed

project, parking arrangement etc.

Refer Chapter3, Section 3.12 of the EIA

report

(x) Detailed description of flora and fauna

(terrestrial and aquatic) existing in study area shall

be given with special reference to rare, endemic

and endangered species. If Schedule- I fauna are


report






found within the study area, a Wildlife

Conservation Plan shall be prepared and furnished.

(xi) Socio-economic status of the study area. Refer chapter 3, section 3.11 of the EIA

report

7. Impact and Environment Management Plan

(i) Assessment of ground level concentration of

pollutants from the stack emissions based on site-

specific meteorological features. In case the project

is located on hilly terrain, the AQIP Modeling shall

be done using inputs of the specific terrain

characteristics for determining the potential

impacts of the project on the AAQ . Cumulative

impact of all sources of emissions (including

transportation) on the AAQ of the area shall be

assessed. Details of the model used and the input

data used for modelling shall also be provided. The

air quality contours shall be plotted on a location

map showing the location of project site, habitation

nearby, sensitive receptors, if any.

Refer chapter 3 of the EIA report

(ii) Water quality modelling- in case of discharge in

water body.

Waste water will be treated in the ETP on

the project site itself.

(iii) Impact of the transport of the raw material and

end products on the surrounding environment shall

be assessed and provided. In this regard, options

for transport of raw materials and finished products

and wastes (large quantities) by rail or rail-cum

road transport or conveyor-cum-rail transport shall

be examined.

The plot surrounding has general

infrastructure facilities for transport of raw

material and end product i.e. railways siding

for dispatch of products, approach road, and

pipeline for disposal of effluents.

(iv) A note on treatment of wastewater from

different plant operations, extent recycled and

reused for different purposes shall be included.

Complete scheme of effluent. Characteristics of

untreated and treated effluent to meet the

prescribed standards of discharge under E(P) Rules

Refer chapter 9, section 9.5.1.2 of the EIA

report.

(v) Details of stack emissions and action plan for

control of emission to meet standards


(vi) Measures for fugitive emissions control. Refer to chapter 9 of the EIA report

(vii) Details of hazardous waste generation and

their storage, utilization and management. Copies

of MoU regarding utilization of solid and hazardous

waste in cement plant shall also be included. EMP

shall include the concept of waste-minimization,

recycle/reuse/recover techniques, energy

conservation and natural resource conservation

Refer to chapter 9, section 9.8.2.2 of the EIA

report.






(viii) Proper utilization of fly ash shall be ensured as

per Fly Ash Notification, 2009. A detailed plan of

action shall be provided.

Not applicable

(ix) Action plan for the green belt development plan

in 33 % area i.e. land with not less than 1,500 trees

per ha. Giving details of species, width of

plantation, planning schedule etc. shall be included.

The green belt shall be around the project

boundary and a scheme for greening of roads used

for the project shall also be incorporated.

Refer chapter 9, section 9.2.5 of the EIA

report.

(x) Action plan for rainwater harvesting measures at

plant site shall be submitted to harvest rainwater

from the roof tops and storm water drains to

recharge the ground water and also to use for the

various activities at the project site to conserve

fresh water and reduce the water requirement

from other sources.

Rainwater harvesting measures at plant site

shall be implemented to harvest rainwater

from the roof tops and storm water drains to

recharge the ground water and also to use

for the various activities at the project site to

conserve fresh water and reduce the water

requirement from other sources.

(xi) Total capital cost and recurring cost/annum for

environmental pollution control measures shall be

included.

The capital and recurring cost for 2015-16 is

Rs. 72 Lakh (Approx)

(xii) Action plan for post-project environmental

monitoring shall be submitted


(xiii) Onsite and Offsite Disaster (natural and Man-

made) Preparedness and Emergency Management

Plan including Risk Assessment and damage

control. Disaster management plan should be

linked with District Disaster Management Plan.


8. Occupational health

(i) Plan and fund allocations to ensure the

occupational health & safety of all contract and

casual workers

Refer Annexure-I (Quality, Safety, Health &

Policy)

(ii) Details of exposure specific health status

evaluation of worker. If the workers health is being

evaluated by pre designed format, chest x-rays,

Audiometry, Spirometry, vision testing (far & near

vision, colour vision and any other ocular defect)

ECG, during pre placement and periodical

examinations give the details of the same. Details

regarding last month analyzed data of above

mentioned parameters as per age, sex, duration of

exposure.


Policy).

All workers are provided with suitable

personal protective equipments (PPE).

Regular safety and environmental awareness

programmes are being conducting in the

nearby villages to promote awareness of the

local villages. BGR is also taking up periodic

health check programmes for the nearby

villages is also being taken care







(iii) Details of existing Occupational & Safety

Hazards. What are the exposure levels of hazards

and whether they are within Permissible Exposure

Level (PEL). If these are not within PEL what

measures the company has adopted to keep them

within PEL, what measures the company has

adopted to keep them within PEL so that health of

the workers can be preserved.

Policy).

All workers are provided with suitable

personal protective equipments (PPE).

The air & noise levels are regularly

monitored and they are within permissible

limits (Refer Chapter 3)

The workers working in high noise level

generating area shall undergo audiometric

test once in a six months.

VOC levels are determined regularly. The

new project will implement Sulphur - De-

Sulphurisation technology.

Proper designing of building, work area,

good ventilation, good exhaust system & air

circulation. To relieve them from thermal

stress, provision of relaxation facilities.

Isolation to specific areas, Rotation of

workers/shifts to avoid continuous

exposure, Enforcement & encouragement to

use PPE

(iv) Annual report of health status of workers with

special reference to Occupational Health and

Safety.

Occuational Health Survelliance is regular

exercise at BGR. The health check ups will

carried out periodically and medical records

of all employees shall be maintained

separately.

The medical check up will include Chest X-

Ray, Audiometry, Spirometry, Haemogram,

ECG, Vision testing (Far & Near vision, color

vision and any other ocular defect). Urine

(Routine and Microscopic), Complete

Physical examination, Fatigue, Backache,

Muco Skeletal disorders, (MSD), major &

minor joint pains will be examined and given

appropriate remedy/treatment.






9. Corporate Environment Policy

(i) Does the company have a well laid down

environment Policy approved by its Board of

Directors? If so, it may be detailed in EIA

report.

Indian Oil Corporation Ltd., Bongaigaon

Refinery (BGR) has its own well established

Quality, Safety, Health and Environment

(QSHE) Policy approved by Executive

Director, BGR.

Refer Annexure-I in the EIA report

(ii) Does the environmental policy prescribe for

standard operating process/procedures to

bring into focus any infringement/deviation

/violation of the environmental or forest

norms/conditions? If so, it may be detailed in

the EIA.

Not applicable

(iii) What is the hierarchical system or

Administrative order of the company to deal

with the environmental issues and for ensuring

compliance with the Environmental Clearance

conditions? Details of this system may be

given.

Refer Annexure - XI, Organogram Of

Environment, (Health, Safety and

Management)

(iv) Does the company have system of reporting of

non compliances/ violations of environmental

norms to the Board of Directors of the

company and or/ shareholders or stakeholders

at large? This reporting mechanism shall be

detailed in the EIA report

(a)Status of Consent to operate, Treated

Effluent quality , Ambient Air Quality and

Hazardous Waste Management details are

displayed in BGR main gate for public

viewing .

(b) LED display Boards are installed at Main

Gate of BGR for Stack Emission, Treated

Effluent, Amb. Air Quality and

Meteorological data for public viewing.

Online Stack emission data - Amb. Air quality

and Treated Effluent quality, are linked with

IOCL- Ref. Head Quarter as well CPCB &

PCBA servers.

10. Details regarding infrastructure facilities such as

sanitation, fuel, restroom etc. to be provided to the

labor force during construction as well as to the

casual workers including truck drivers during

Operation phase.

Proper infrastructure facilities will be

provided.

11. Enterprise Social Commitment (ESC)

Adequate funds (at least 2.5 % of the project cost)

shall be earmarked towards the Enterprise Social

Commitment based on Public Hearing issues and

item-wise details along with time bound action plan

shall be included. Socio-economic development

activities need to be elaborated upon.

CSR budget for FY 2016-17 proposed is

Rs.372.60 Lakh which includes:

A. New CSR Projects: Rs.111.00 Lakh.

B. Flag-ship Projects – Indian Oil

Chikitsa Seva Kendra : Rs.6.60 Lakh &

C. School – Rs. 255.00 lakh.






12. Any litigation pending against the project and/or

any direction/order passed by any court of law

against the project, if so, details thereof shall also

be included. Has the unit received any notice under

Section 5 of Environment (protection) Act, 1986 or

relevant sections of Air and Water Acts? If so,

details thereof and compliance /ATR to the

notice(s) and present status of the case.

Nil

13. A tabular chart with index for point wise

compliance of above TOR.

Provided

SPECIFIC TERMS OF REFERENCE :

1. Complete process flow diagram describing each unit,

its capacity along with material and energy balance.

Refer Chapter 2 in EIA, Refer Annexure-

II, III in the EIA report

2. Details of intermediate product, their storages and

final products to be manufactured.

Refer to Annexure- III, IV in the EIA

report

3. Sulphur balance giving input from crude, refinery fuel

(if used) and any other outside fuel and output in

various products and emissions.

Refer to Annexure -V in the EIA report

4. Details of proposed source-specific pollution control

schemes and equipment to meet the national

standard for petroleum refinery.

Pollution Control schemes are already

in compliance with Revised Standards

for Emissions & Effluent -2008 .

5. Details of emissions from all the stacks including

volumetric flow rate.

Refer to Annexure VI in the EIA report

6. Details on availability of raw material (crude oil,

natural gas, chemicals, etc.), its source and storage at

the plant.

• Raw material – Crude oil

• Assam crude oil source – Assam

oilfield

• Imported crude oil source –

Paradip port in East coast

7. Details of mode of transportation of crude and

products. Details of mode of transportation of crude

and products.

• Transportation mode are given

below:

o Crude oil–pipeline

o Product–Truck, Rake & pipeline

• Crude storage capacity in 7 crude

tanks : 7 x 20,000 KL = 1,40,000

KL

8. Details of storage capacity of crude and products. Refer chapter 9 of the EIA report

9. Ambient air quality data should include hydro carbon

(methane and non -methane), VOC. Ni & V etc.


10. Efforts to minimize water consumption, effluent

discharge and to maintain quality of receiving water

body.

No treated water will be discharged in

any water body. Effluent will be treated

in ETP and the treated effluent will be

recycled.

11. Details of effluent at treatment plant, inlet and

treated water quality with specific efficiency of each

Refer Annexure-VIII, IX in the EIA report






treatment unit in reduction in respect of all

concerned/ regulated environmental parameters.

Also, include treatment details such as primary

(physico-chemical), secondary (biological) and tertiary

(activated carbon filters) treatment systems.

12. Storm water management plan One main Storm water channel is

routed thru Eco Park of capacity 65000

m3 where storm water quality further is

improved by natural aeration, Floating

fountain, and artificial waterfall. A

Seasonal rivulet carrying rain water run

off from neighbouring area flows

through BGR factory premises to

outside.

All storm water channels are provided

with series of sand trap to stop solid

particle flowing to outside and oil trap

to arrest spill over of oil to outside of

BGR factory premises.

13. Estimation of SO2 and NOx emissions load In 2015-16, Emission load:

SO2= 1,043 MT/Yr & NOx = 611 MT/yr

14. Details on flaring system. 3 no. of tall Flares for Ref-1+2, CRU -

MSQ, DHDT plant and one for Sulphur

Recovery unit.

15. Details of VOC recovery devices in the storage tanks. All Crude storage tanks and other light

HC storage tanks are already provided

with double seal protection system.

16. Arrangements for spill management. Spill is collected Unit Oil Separators and

recovered as slope and reprocessed in

delayed coking unit. Melting pit facility

is also available for its management.

17. Oily sludge management plan Refer Annexure- VII in the EIA report

18. Risk Assessment & Disaster Management Plan:

(i) Identification of hazards Refer to chapter 7 of the EIA report

(ii) Consequences Analysis Refer to chapter 7 of the EIA report

(iii) Risk assessment should also include leakages and

location near to refinery & proposed measures for risk

reduction.


(iv) Arrangement for fire protection and control. Refer to chapter 7 of the EIA report






COMPLIANCE TO TERMS OF REFERENCE ISSUED BY EXPERT APPRAISAL

COMMITTEE - I

S.No TOR Compliance

1 Public hearing to be conducted and issues

raised and commitments made by the

project proponent on the same should be

included in EIA/EMP Report in the form of

tabular chart with financial budget for

complying with the commitments made.

Public hearing will be conducted and the

commitments made will be included in

the EIA report.

2 A separate chapter on status of

compliance of Environmental Conditions

granted by State/Centre to be provided.

As per circular dated 30th May, 2012

issued by MoEF, a certified report by RO,

MoEF on status of compliance of

conditions on existing unit to be provided

in EIA-EMP report.

Is included in the report as Annexure-X.

3 Plan for ZLD to be drawn The total liquid effluent generated in the

units and residential Township is treated

in Effluent Treatment Plant and further

polished in Tertiary Treatment Plant for

reuse as Cooling Water make up, Fire

Water make up and house keeping of the

plant units. In 2015-16, 97.4% of effluent

generated was reused. Rest quantity is

discharged through Eco park having

retention capacity 65,000 m3 for make up

the evaporation loss and further aeration.

During incessant rainy days, storm water

is flowing through Tunia rivulate. In dry

season, Zero Liquid Discharge is

complied.






CHAPTER 1






CHAPTER 1: INTRODUCTION 1.1 Background

The Bongaigaon Refinery is the eighth refinery of IOCL, formed upon the amalgamation of

Bongaigaon Refinery & Petrochemicals Limited (BRPL) with Indian Oil on March 25. 2009.

Bongaigaon refinery is situated at Dhaligaon in Chirang district of Assam, 200 km west of

Guwahati.

The Bongaigaon Refinery initial capacity of 1.00 MMTPA and commissioned in 1979. The

crude capacity was further increased to 1.35 MMTPA in 1986. Presently refinery has two

Crude Distillation Units (CDU) of each capacity 1.35 MMTPA, two Delayed Coker Units (DCU)

and a Coke Calcination Unit (CCU). The refinery has implemented Diesel Hydrotreatment

(DHDT) project and MS Quality Improvement (MSQ) project in 2011. For the first time in

India, technology indigenously developed by M/s IOCL (R&D) and Engineers India Limited

(EIL) is being adopted for these two projects.

Now the company intends to expand, revamp, implement new processing and pollution

control technologies and there units. In view of the Auto-Fuel Policy Vision 2025, the

Refineries will be required to supply fuels meeting the BS-IV specification fuels by 1st April

2017 and BS-VI specification by 1st April, 2020. Bongaigaon Refinery has proposed crude

enhancement capacity from 2.35 to 2.7 MMTPA, DHDT capacity.

Ministry of Environment & Forests (MoEF) has granted environmental clearance to

Bongaigaon Refinery vide letter no. J-11011/9/2008/- IA II (I) dated 2nd September, 2008 for

INDMAX Project.

Environment plays a vital role in overall development of the country. Recognizing the

importance of environmental protection and sustainable development, the Ministry of

Environment, Forest and Climate Change (MoEF&CC), Government of India had formulated

policies and procedures governing the industrial and other developmental activities to

prevent indiscriminate exploitation of natural resources and promote integration of

environmental concern in industrial projects. To assess and evaluate potential

environmental impacts during design, construction & operation phases and to suggest

mitigation measures with detailed environmental management plan, environmental impact

assessment study has been conducted for the proposed project.

M/s ABC Techno Labs India Private Limited (ABC Techno Labs), NABET Accredited

Environmental Consultant Organisation, has been engaged by M/s Indian Oil Corporation

Ltd. (IOCL) to carry out Environmental Impact Assessment studies for the proposed INDMAX

Project and expansion of capacity of various units of existing refinery.

1.2 Need of the Expansion of Bongaigaon refinery

The present crude processing capacity is 2,350,000 TPA of Assam Crude Oil and Low Sulphur

Imported Crude Oil. In view of the Auto-Fuel Policy Vision 2025, the Refineries will be

required to supply fuels meeting the BS-IV specification fuels by 1st April 2017 and BS-VI

specification by 1st April, 2020. The BS-VI will bring down the Nitrogen Oxide emissions from






diesel cars by 68 % and 25% from petrol engined cars. Cancer causing particulate matter

emissions from diesel engine cars will also come down by a phenomenal 80% is

implementing the following projects:

i. Crude processing capacity enhancement from 2.35 MMTPA to 2.7 MMTPA

ii. DHDT capacity enhancement from 1,200 TMTPA to 1,800 TMTPA to meet BS-VI

HSD specification.

iii. CRU-MSQ revamp to meet BS-VI MS specification.

iv. INDMAX Project along with Indmax Gasoline De-Sulphurisation Unit.

v. Selective Desulphurisation (SDS) Unit.

1.3 Need of EIA

As per EIA Notification S.O. No 1533 issued on 14th September, 2006 and its subsequent

amendments, the proposed expansion of the BGR INDMAX project is falling under Schedule

4(a) – Petroleum Refining Industry. Hence, this project requires Environmental Clearance

from Ministry of Environment & Forest (MoEF) through Expert Appraisal Committee (EAC),

Accordingly, the EIA Report has been prepared based on the Terms of Reference approved

during 5th Meeting of Expert Appraisal Committee - 1 held on 25th & 26th February, 2016

for the BGR INDMAX plant and expansion of other facilities in BGR complex.

1.4 Terms of Reference (TOR)

During 5th Expert Appraisal Committee (EAC) meeting held on 25th & 26th February, 2016,

the project was considered and after detailed discussions the Committee prescribed the

following additional points which need to be added in model ToR applicable for category

4(a). The EIA report has been prepared as per TOR approved by SEAC. The compliance of

TOR is given in the beginning of EIA Report.

1. Public hearing to be conducted and issues raised and commitments made by the

project proponent on the same should be included in EIA/EMP Report in the form of

tabular chart with financial budget for complying with the commitments made.

2. A separate chapter on status of compliance of Environmental Conditions granted by

State/Centre to be provided. As per circular dated 30th May, 2012 issued by MoEF, a

certified report by RO, MoEF on status of compliance of conditions on existing unit to

be provided in EIA-EMP report.

3. Plan for ZLD to be drawn

1.5 Approach and Methodology

The primary objective of the EIA study is to internalize and integrate the environmental

concerns /aspects and mitigation measures due to proposed expansion at Bongaigaon

Refinery.

The EIA study for proposed expansion at Bongaigaon Refinery has been carried out with the

following objectives:






� Collection of baseline attributes in study area. The EIA covers baseline environmental

data, as per the guidelines of MoEF & CC. The scope includes collection of baseline

data to identify the various environmental parameters such as air, water, soil, noise

levels, socio - economic factors, land use factors, the status of the flora- fauna and

wildlife in the adjoining areas of the proposed project site.

� Identification, prediction, evaluation & mitigation of biophysical, social & other

relevant effects of development on the environment during the operational phase of

the proposed expansion at Bongaigaon Refinery sing mathematical / simulation

models as per applicable Indian law.

� Preparation of risk assessment & emergency preparedness / disaster management

plan for the project.

� Preparation of Environmental Management Plan (EMP) to be adopted for mitigation

of the anticipated adverse impacts of the proposed expansion at plant during

operational phase.

� Delineation of the post project environmental quality monitoring program as per the

requirements of the regulatory authorities.

To carry out EIA study for the proposed expansion, reconnaissance survey was conducted by

field team of ABC Techno Labs India Pvt. Ltd. and sampling locations for various

environmental parameters were identified on the basis of:

� Predominant wind direction expected during the period of baseline monitoring in the

study area

� Topography,

� Location of village/towns/sensitive areas

� Identified pollution pockets, if any within the study area

� Areas, which represent baseline conditions;

� Collection, collation and analysis of baseline data for various environmental

attributes.

The field studies and primary data collection have been conducted during November 2015

to 15th March 2016 to determine existing conditions of various environmental attributes.

The proposed expansion at Bongaigaon Refinery could have impact on the physical,

chemical and biological attributes of surrounding environment. In assessing the

environmental impacts, collection, collation and interpretation of baseline data is of prime

importance. Environmental impact analysis and assessment is preferably carried out at the

planning stage itself.






1.6 Environmental Settings

The environmental settings of the Bongaigaon Refinery, Assam are given in following

subsections:

1.6.1 Location Details of the Site

The location of refinery capacity enhancement project, which is in existing premises of

refinery on Google satellite image and surrounding area is shown in Figure 1.1.

IOCL Bongaigaon Refinery is located at Tehsil: Sidli Part II, Revenue survey no. 450,

Dhaligaon, District-Chirang, Assam State, India.

The latitude -longitude of the refinery are as follows:

Latitude : 26°31’00.81"N

Longitude : 90°31'53.85“E

The main geographical features of the Bongaigaon Refinery project are given below:

� The average ground level elevation of project site is 63m above the mean sea level.

� It is 8 km away from the New Bongaigaon railway station

� National Highway – NH 31C -0.7 km away from the project site.

� Nearest Airport: Lokopriya Gopinath Bordoloi International Airport, Guwahati, 180

Km away from project site.

� Nearest village: Dhaligaon at 1 Km (approx.)

� Topography is generally plain lands, No hilly areas, No valleys around 5 km radius

area from the project site.

� There is no archaeological monument within the 5 km radius of the project siteThere

is no critical polluted area within 10 km radius area.

� There is no state boundary within 10 km radius.

� There is no national park/wildlife sanctuary within 5 km radius area from site.

(Nakkati Reserved Forest- 7.5km, Kakoijana Reserved Forest- 9.5km, Bhumeswar

Reserved Forest- 7.8km).

� Distance of Lakes that are situated near the projects sitee mentioned ahead:

Nayachara Lake (Beel) -7.0km, Bhosamari -9.2 km, Paropota Lake -9.5 km, Naodora

Lake -9.2 km, Kasorani Lake -9.2 km .

� Distance of rivers that are situated near the projects site are mentioned ahead: River

Aie -6.0 km, River Tunia -4.0km, River Kujia -7.0 km

The location of refinery on map is shown in Figure 1.2. 10 km radius of study area on Google

map is given in Figure below






1.6.2 Accessibility to Plant Site

The refinery plant is located at Dhaligaon, Assam State. The National Highway NH 31C is 0.7

Km away from the project site. Nearest operational airport is at Guwahati, which is about

180 km from the Project site.






1.7 EIA Report Presentation

The EIA report for refinery expansion for enhancing the crude process capacity from 2.35

MMTPA to 2.7 MMTPA, DHDT capacity enhancement by 1.2 - 1.8 MMTPA, CRU-MSQ

revamp and Implement of SDS unit at Tehsil Sidli (PT-II), District-Chirang, Assam, has been

prepared as per TOR approved during 5th Expert Appraisal Committee (EAC) meeting held

on 25th & 26th February, 2016. The EIA report has been presented in order to group the

environmental parameters under physical, biological, demographic & socio-economic

environments, anticipated impacts and mitigation measures. The EIA report has been

prepared as contents given in EIA Notification 2006 and subsequent amendments. The

structure of EIA Report is as given below:

Compliance of TOR

Executive Summary: given in the beginning of the report.

Figure 1.1: Index Map of BGR INDMAX project






Chapter 1: Introduction

This chapter provides background information, brief location settings of the area. The terms

of reference for preparation of EIA/ EMP and structure of EIA report have also been

described in this chapter.

Chapter 2: Description of the Project

This chapter deals project details, project layout, design details, operating parameters,

power requirements, water requirement and sources of pollution and it management, cost

of proposed expansion, etc.

Chapter 3: Description of the Environment

This chapter presents existing environmental status of the 10 km radius study area around

the proposed project including topography, geological, drainage pattern, water

environment, climate & meteorology, ambient air quality, noise levels, flora & fauna, socio-

economic, etc.

Chapter 4: Anticipated Environmental Impacts & Mitigation Measures

This chapter describes the anticipated impact on the environment and mitigation measures

for proposed project. Assessment of anticipated Environmental Impacts. It gives the details

of the impact on the baseline parameters, both during the construction and operational

phases and suggests the mitigation measures to be implemented by the IOCL Bongaigaon

Refinery.

Chapter 5: Analysis of Alternatives

This chapter examines alternative means for the proposed project

Chapter 6: Environmental Monitoring Plan

This chapter describes Environmental Monitoring Plan for the proposed project during

construction and operation phases.

Chapter 7: Additional Studies (Risk Analysis and Disaster Management Plan)

This chapter spelled out hazard identification, risk analysis and disaster management plan

for an unlikely event of emergency at LPG Plant.

Chapter 8: Project Benefits

This chapter includes the benefits in terms of improvement in physical infrastructure, social

infrastructure, employment potential, etc.

Chapter 9: Environmental Management Plan (EMP)

This chapter describes environmental management plan to mitigate adverse environmental

impacts and to strengthen beneficial impacts.

Chapter 10: Disclosure of Consultant engaged

This chapter comprises the name of consultants engaged with their brief resume and nature

of consultancy rendered.






CHAPTER 2






CHAPTER 2

PROJECT DESCRIPTION 2.1 Introduction:

The Bongaigaon Refinery is the eighth refinery of IOCL, formed upon the amalgamation of

Bongaigaon Refinery & Petrochemicals Limited (BRPL) with Indian Oil on March 25. 2009.

Bongaigaon refinery is situated at Dhaligaon in Chirang district of Assam, 200 km west of

Guwahati.

The Bongaigaon Refinery initial capacity of 1.00 MMTPA and commissioned in 1979. The

crude capacity was further increased to 1.35 MMTPA in 1986. Presently refinery has two

Crude Distillation Units (CDU) of total capacity 2.35 MMTPA, two Delayed Coker Units (DCU)

and a Coke Calcination Unit (CCU). The refinery has implemented Diesel Hydrotreatment

(DHDT) project and MS Quality Improvement (MSQ) project in 2011. For the first time in

India, technology indigenously developed by M/s IOCL (R&D) and Engineers India Limited

(EIL) is being adopted for these two projects.

As per the declaration of Government of India dated 6th Jan’16, it has been proposed to

implement BS-VI grade fuel in the entire country w.e.f. 1st April 2020 i.e. switching over

directly from BS-IV grade fuels to BS-VI grade fuel. Thus it is imperative that the refinery up

gradation should consider the production of BS-VI grade fuels by inducting suitable new

units and revamp of exiting units

The above proposed plant capacity enhancement are mentioned below:

It is implementing the following projects:

1. Crude processing capacity enhancement from 2.35 MMTPA to 2.7 MMTPA

2. DHDT capacity enhancement from 1,200 TMTPA to 1,800 TMTPA to meet BS-VI HSD

specification.

3. CRU-MSQ revamp to meet BS-VI MS specification.

4. INDMAX Project along with Indmax Gasoline De-Sulphurisation Unit.

5. Selective Desulphurisation (SDS) Unit.

2.2 Needs of Capacity Enhancement

The present crude processing capacity is 2,350,000 TPA of Assam Crude Oil and Low Sulphur

Imported Crude Oil. In view of the Auto-Fuel Policy Vision 2025, the Refineries will be

required to supply fuels meeting the BS-IV specification fuels by 1st April 2017 and BS-V

specification by 1st April, 2020.

The project being proposed is important in view of the demand of HSD. The BS-VI will bring

down the Nitrogen Oxide emissions from diesel cars by 68 % and 25% from petrol engine

cars. Cancer causing particulate matter emissions from diesel engine cars will also come

down by a phenomenal 80 %. Therefore this project has national importance and will also






contribute to the socio economic development the region. IOCL has proposed to implement

new technology, revamp and enhance capacity of the units.

2.3 Project Location

The location of capacity enhancement project on Google satellite image and surrounding

area is shown in Figure:2.1

IOCL Bongaigaon Refinery, is located at Tehsil: Sidli Part II, Revenue survey no. 450,

Dhaligaon, Chirang District, Assam State, India.



Assam


Figure 2.1: Location of Bongaigaon refinery at Dhaligaon, Assam on Google Satellite Image



Assam


Figure 2.2: Plot Plan of Bongaigaon Refinery






2.4 Manufacturing Process Details

[I] Crude Processing Capacity Enhancement:

Presently crude processing capacity of BGR is 2.35 MMTPA having two Crude Distillation

Units (CDU)

• CDU-I having nameplate capacity of 1.35 MMTPA

• CDU-II having nameplate capacity of 1.00 MMTPA

•

After OIL crude pipeline HBCPL capacity enhancement from 7.5 to 9.2 MMTPA, crude

availability to BGR will be 2.7 MMTPA.

To process crude of 2.7 MMTPA at BGR, it is proposed to increase the nameplate capacity of

CDU-II unit from 1.0 MMTPA to 1.35 MMPTA. No additional facility is required for this

project.

[II] DHDT Capacity enhancement project to meet BS-VI HSD specification:

Bongaigaon Refinery proposes DHDT Capacity enhancement to implement Project” (from

capacity of 1,200 TMTPA to 1,800 TMTPA) at its existing refinery complex. BGR can supply

BS-IV HSD as per the deadline of the Auto Fuel Policy. However, in order to supply BS-IV HSD

at the same quantity of HSD being produced presently may not be possible due to reduction

in back blending of HSD components due to capacity limitation of the existing DHDT unit.

Salient features of the proposed project:

Project objectives: The objectives of the project are as follows:

• The refinery has to produce BS-VI HSD at the current level of BS-III HSD production

without reducing crude throughout

Facilities: The following changes are envisaged in the capacity expansion of DHDT unit.

a) Additional feed pump

b) Additional feed effluent exchangers

c) Revamp of recycle gas compressor

d) Furnace tube size change from existing 6" to higher size to reduce

the high pressure drop. Changes in the firing side of the furnace is

not anticipated as the furnace thermal loading was only around

65% at 126% load






e) Change of around 12 control valves to higher sizes.

f) Change in internals of stripper & stabilizer columns

g) Change in over head exchangers of stripper & stabilizer.

h) Change in piping can be estimated during detailed engineering.

i) One new fractionating column for continuous production of ATF &

HSD from the present blocked out mode operation.

j) Partial change of catalyst with a bed of hydro-cracking catalyst in

the last reactor to have improvement in 95% recovery

k) Offsite transfer pumps

l) Installation of Hot Separator.

Project Cost and schedule: The ballpark cost estimate of the proposed DHDT project is Rs.

200 Crore. The project is scheduled to be completed by April, 2019.

The DHDT unit of BGR is designed to process 1,200 TMTPA of HDT feed with balance 25- 30

% directly back blended to HSD. The diesel produced ex-DHDT unit meets BS-V specification,

specially the stringent sulfur specification of 10 ppm. However, in BS-VI regime, the total

quantity of HSD feed streams will have to be processed via DHDT unit to meet the sulphur

and Cetane specification of BS-VI HSD.

In order to sustain HSD production at the existing level under BS-VI scenario, the capacity of

the DHDT plant is required to be increased to 150% of the existing capacity i.e. to 1,800

TMTPA from the existing level of 1,200 TMTPA to process all available diesel feed streams.

In order to have clarity the HSD specifications for BS-III, BS-IV & BS-VI HSD is tabulated

below:

Table no.2.1: Specification of Diesel

SPECIFICATIONS OF DIESEL

S. No. Attribute Unit BS-III BS-IV BS-VI

1

Density @15°C

kg/m3,

max 820-845

820-845 820-860

2 Distillation T95 °C Max 360 360 370

3 Sulphur ppm max 350 50 10

4

Cetane No

min 51 51 51 (For NE states,

CN requirement till

1st April 2023 shall






be min 48)

5 Cetane Index min 46 46 46

6 Flash Point °C min 35 35 42

7 Viscosity @ 40°C cSt 2.0-4.5 2.0-4.5 2.0-4.5

8 PAH % wt max 11 11 11

9

Total Contaminants

mg/Kg

max

24 24 24

10 RCR on 10% Residue % wt max 0.3 0.3 0.3

11

Water Content

mg/Kg

max

200 200 200

12 Lubricity, Corrected

Wear Scar Diameter

(WSD) @ 60°C

Microns,

max

460 460 460

13 Ash % wt max 0.01 0.01 0.01

14 Cold Filter Plugging

point

14 a) Summer Max °C 18 18 18

14b) Winter Max °C 6 6 6

15 Oxidation Stability g/m3 max 25 25 25

16 Copper Strip

corrosion for 3hrs @

50°C, max

Rating Class 1 Class 1 Class 1

[III] CRU-MSQ Revamp to meet the BS-VI MS specification:

Bongaigaon Refinery proposes to implement the CRU-MSQ “revamp project”. In order to

meet the aromatic limit of 35 vol% in MS, the Light Naphtha ISOM unit will have to be

revamped with a new catalyst along with re-orientation of process configuration to produce

Isomerate of RON 90 from the present level of 85. Possibility of RON improvement by

changing the catalyst from present zeolite based catalyst to Sulfated Zirconia based catalyst

has been discussed with Licensors.

Further to meet Sulphur level of < 10 ppm in BS-VI MS a new Naphtha Hydrotreater will

have to be installed for hydrodesulphurization of the straight run naphtha.

A detailed study of the Light Naphtha Isom units required to be carried out for identifying

the modifications and for preparation of the feasibility report.

In order to absorb all the naptha into MS, the capacity revamp of the CRU unit is required to

be increased from the present 160 TMTPA to around 200 TMTPA.

Further, BGR is exploring the option of revamping the existing Isomerisation unit with an

additional reactor for improving Isomerate RON from present 84-85 to 90 -91 for which, M/s






GTC Technologies is being consulted for putting up an additional reactor with Sulfated

Zirconia based catalyst.

Salient features of the proposed project:

Project objectives: The refinery has to produce BS-VI MS

Revamp of Light Naphtha Isomerisation Unit:

The changes envisaged in the Isomerisation Unit are:

• Installation of a new naphtha hydrotreatment unit to reduce sulfur from present

level of 50-100 ppm to < 8ppm

• Change of catalyst

• Changing the existing reactors, feed effluent exchangers, trim coolers

• New makeup gas compressor

•

Capacity expansion of Catalytic Reformer Unit:

In order to sustain MS production at the present levels RON barrel has to be increased

which can be achieved by expanding of the CRU unit by processing a wider cut of RFN.

The following modifications are envisaged

• Additional feed pump,

• Furnace modification (increase of tube dia from 4”to 6”, increase of tube length and

increase in number of burners from one to three in each furnace) to accommodate

the pressure drop of higher hydraulic load,

• Change of compressor (Reciprocating to centrifugal)- optional

• Changing column internals of Stabilizer and Reformate Splitter,

• Installing marginally higher capacity reactors on the same foundations

• Loading of high performance catalyst for enhanced performance at lower space

velocities.

Project Cost and schedule: The ballpark cost estimate of the proposed CRU-MSQ project

is Rs. 610 Crore. The project is scheduled to be completed by April, 2019.

[IV] Indmax project:

Bongaigaon Refinery proposes to implement the “Indmax FCC unit along with Indmax

Gasoline De-Sulphurisation Unit) at its existing refinery complex at Dhaligaon to eliminate

production of demand limited black oils (LDO, LVFO & LSHS) and Naphtha and produce high

value products like LPG and Motor Spirit (MS) conforming to BS- VI specifications.

Salient features of the proposed Indmax Project:

Project objectives: The objectives of the Indmax Project are as follows: • Eliminate production of demand limited Black Oil and Naphtha






• Maximize production of high value LPG

• Maximize production of high value Motor Spirit (BS-VI)

Facilities:

The Indmax Project will consist of the following facilities:

• INDMAX FCC unit with a design capacity of 740,000 MTPA. The INDMAX process has

been developed and patented by IOCL (R&D). IOCL (R&D) and Lummus Technology

Inc., USA will be the joint licensors for the unit.

• LPG treatment facility as part of the INDMAX FCC Unit.

• Indmax Gasoline De-Sulphurisation Unit with a design capacity of 312,000 MTPA to

reduce Sulphur content in Indmax Gasoline so to meet BS-VI equivalent

specifications for Motor Spirit.

Existing utilities & Offsite facilities will be utilized for the Indmax project with the following

additional facilities:

• Additional storage and transfer facilities for LPG to match with the requirement as

per the production

• One additional cooling water circulating pump of 2,600 m3/hr capacity

• One cell in DM water plant.

•

Indmax Unit Process:

Presently, Coker Naphtha and Coker Gas Oil & Coker Fuel Oil from Delayed Coker Unit are

being blended and evacuated as BS-II Motor Spirit (MS) and LDO & LVFO respectively. With

the implementation of Euro-III equivalent fuel norms effective from 2010, it will not be

possible to blend Coker Naphtha in the MS pool and will surplus as Naphtha. Also, increasing

availability and demand of Natural Gas, the demand of Naphtha and LDO/LVFO (Black Oil)

are decreasing day by day.

In view of the above, BGR is implementing INDMAX Unit of 740 TMT per annum capacity at

BGR to process Coker Naphtha, Coker Heavy Gasoil (CHGO), Reduced Crude Oil (RCO) and

Black Oil components and thereby to increase value added products LPG and MS.

The feed to the INDMAX Unit of BGR comprises of Coker Naphtha (CN), Coker Heavy Gasoil

(CHGO) and Coker Fuel Oil (CFO) from Delayed Coker units & Reduced Crude Oil (RCO) ex

Crude Distillation units.

INDMAX is proprietary process developed and patented by IOCL (R&D) similar to Residue

Fluid Catalytic Cracking (RFCC) process except that the catalyst system and operating

conditions are different. With the optimum catalyst formulation, very high catalytic

conversion and maximum LPG and light olefin yields are ensured, while making the lowest

dry gas and coke yield. INDMAX catalyst demonstrates an exceptionally high vanadium

tolerance (21000 ppm on eCat), which is twice that of a conventional RFCC catalyst.






Main features of the process are:

• Feed CCR limitation is 4.0 wt%. The total Ni/V on feed should be less than 80/40 ppm

respectively.

• Higher conversion yields higher LPG and light olefin due to the excellent dry gas and

coke selectivity of the proprietary catalyst.

• Produces very high octane gasoline (RON: 95-104) compared to that of 89-92 in

conventional FCCU.

• Improved coke selectivity permits a very high cat/oil ratio (15-25), as compared to

the other state-of-the art processes.

• Significantly higher catalyst to oil ratio provides very efficient heat transportation

from the regenerator to the riser.

• Employs higher riser temperature (560 oC), and a relatively high dilution steam rate

(15-20 wt% of feed).

The products from the proposed INDMAX Unit and their routings will be as below:

[A] Fuel Gas: The off gas from INDMAX Unit (approx 7.7 wt% of INDMAX feed) will be

treated to remove H2S and the treated off gas will be utilized internally as Fuel Gas.

Utilization of off gas as FG will reduce Fuel Oil consumption in the refinery.

[B] LPG: The LPG components produced in the INDMAX Unit (approx 29.5 wt% of INDMAX

feed) will be treated within INDMAX Unit to conform meet LPG quality as per IS: 4576-

1999 and sent to Storage.

[C] Gasoline: There will be two gasoline streams from INDMAX Unit –Light Indmax Gasoline

(C5-15 oC) and Heavy Indmax Gasoline (150-210 oC). With the INDMAX Gasoline

blended to MS pool, the MS pool would only meet the quality specifications of MS

conforming to BS-VI equivalent norms with respect to Sulphur. In view of the above,

both Lt and Hy Indmax gasoline will be routed to INDMAX Gasoline De-Sulphurisation

Unit before routing to the refinery MP pool conforming to BS-VI equivalent

specifications.

[D] Light Cycle Oil (LCO): The Light Cycle Oil will be partly routed to refinery Diesel pool

conforming to BS- VI equivalent norms and partly will be consumed as IFO.

[E] Clarified Oil (CLO): The Clarified Oil will be processed in Delayed Coker Unit for

production of Needle Coke. With processing of CLO in DCU, RCO will be surplus and

the surplus RCO will be fed to the INDMAX Unit.

[F] Coke: Approx 7.8 wt% of feed will be deposited on the catalyst as coke which will be

burnt during regeneration of catalyst and thereby steam will be generated in waste

heat boiler. With this generation of steam in INDMAX Unit, load to CPP/GTG will

reduce and thereby fuel consumption will reduce. It is to be noted that care has been

taken in design of INDMAX Unit to minimize emission/pollution from the regenerator.






Indmax Gasoline De-Sulphurisation Unit process:

The Indmax Gasoline if blended in refinery MS pool, the MS pool would not meet the Euro-

IV equivalent MS specs with respect to Sulphur. The objective of the Indmax Gasoline De-

Sulphurisation Unit is to de-sulphurise Light and Heavy Indmax Gasoline so that when

blended with the refinery MS pool, the MS pool meets the BS-VI equivalent MS specs. The

technology Licensor for the Indmax Gasoline De-Sulphurisation Unit will be selected on

competitive bidding basis.

In the Indmax Gasoline De-Sulphurisation Unit, the both Light Indmax Gasoline and Heavy

Indmax Gasoline will be processed in Selective Hydrogenation Unit (SHU).

The required Hydrogen for the process will be supplied from the Hydrogen Generation Unit

(HGU) implemented along with ongoing DHDT project.

The stream ex-SHU reactor will be split in splitter section into two cuts namely LCN (C5-100 oC cut) and HCN (100-150 oC cut).

The LCN (C5-100˚C) from the Splitter top will directly be routed to Stabilizer.

The HCN (100-150 oC cut) from the Splitter bottom will be first treated in Di-olefin and then

will be hydro-treated in HDS reactor to remove Sulphur. Then it will be routed to stabilizer.

The stream ex-stabilizer will be having sulfur content of 8 ppm to meet the BS-VI MS

specification and it will be routed to MS blend pool reactor

Project Cost and schedule:

The ballpark cost estimate of the proposed Indmax project is Rs. 2,500 Crore. . The project is

scheduled to be completed by April, 2019.

[V] Selective Desulfurisation (SDS) project:

Bongaigaon Refinery proposes Selective Desulfurisation (SDS) to implement Project” at its

existing refinery complex. In BS-VI MS production scenario, Coker Naphtha cannot be

blended to MS pool due to high sulfur content. In order to remove sulfur from coker

naphtha without drop in octane of coker naphtha, BGR Proposes to install Indselect unit, a

selective Desulphurisation process developed by IOC R&D.

Salient features of the proposed Selective Desulfurisation (SDS) Project:

Project objectives: The objectives of the project are as follows:

• To reduce sulphur content of Coker naphtha so that it can be blended to MS in BS-VI

scenario.






SDS is a trickle bed reactor system with single stage once through down flow configuration.

The hydrogen consumption is very low and the reduction in sulfur is very negligible. The SDS

reactor is filled with proprietary catalyst developed by IOC R&D and the conventional guard

bed at the top sufficient enough to handle silica rich Coker streams. The key functionality of

the catalyst is to selectively saturate the diolefins and shift low molecular weight sulfur

compounds to high molecular weight sulfur compounds.

These diolefins are selectively removed under very mild conditions of hydrotreating in SDS

Reactor. Sulfur Shift mechanism, the low boiling sulfur compounds are converted to high

boiling sulfur compounds by combination of low boiling sulfur compounds with olefins. Due

to this reaction, it is possible to segregate the light boiling range gasoline from full range

gasoline by distillation before hydrodesulfurization, since all of its sulfur are shifted to high

boiling region.

The diolefins treated & sulfur shifted stream is separated in to light & heavy cut through a

conventional splitter. The lighter cut which is olefins rich (octane potential) & low sulfur

stream is taken to gasoline pool for blending without any post treatment. In this stream, the

sulfur content is low due to the sulfur shift mechanism, all low boiling sulfur compounds are

ended up in the heavy cut.

Facilities: The SDS Project will consist of the following facilities:

• Coker naphtha Feed pump

• Feed effluent exchangers

• SDS reactor

• Stripper with reboiler, cooler and reflux drum

•

Project Cost and schedule:

The ballpark cost estimate of the proposed SDS project is Rs. 33.4 Crore.

Hydrogen Generation Unit (HGU):

The estimate of H2 consumption has been carried out considering existing infrastructure

and there is shortfall of around 25% which needs to be made from existing HGU unit

through a low cost revamp or utilizing available margins.

SRU:

The sulphur balance has been developed for the post INDMAX project. As per the

calculations the refinery requires a New SRU of 10 TPD for post INDMAX / Post BS VI

implementation.

MSQ-NHT:

To reomove the sulphur content of Isom feed to < 10 ppm so as to meet BS-VI MS spec , a

new NHT unit will be installed.






2.5 Power Requirement:

Power Requirement for various utilities is in different forms of Electricity, Steam and Fuel as

mentioned below: Table no. 2.2: Power Requirement

S.

No

Particular CDU-II DHDT CRU-

MSQ

INDMAX

FCC Unit

IGHDS

Unit

SDS

Unit

Total

1 POWER (KW) No

Change

300 No

change

3620 225 45 4220

2 STEAM (MT/hr)

Net SL steam

Net MP steam

Net HP steam

No

Change

No

Chang

e

No

Chang

e

4.5

34.4

(0.3)

-

8.8

-

4.5

43.2

(0.3)

3 FUEL, fuel gas

(MMKcal/hr)

0.63 0.44 0.17 - 0.9 - 2.14

There is no direct requirement of Fuel for INDMAX and SDS unit.

2.6 Water Requirement and Waste Water Generation

Total water consumption will be 370 m3/hr, where 330 m3/hr was required daily and after

the installation of INDMAX unit additional 40 m3/hr of fresh water will be required. The

water demand will be met from the existing facility. No additional raw water will be

required for CDU-II, DHDT, SDS & CRU-MSQ. The plant has installed a 400 m3/hr capacity

Tertiary Treatment Plant. The treated effluent water will be reused as make up water for

cooling tower and green belt development.

2.7 Environmental mitigation measures of the project:

Table no.2.3: Environmental mitigation measures

Particulars Stack Fugitives Liquid Solid Noise

Crude processing

capacity

enhancement

No additional

impact on

emissions

No

additional

impact on

emissions

No

additional

impact on

emissions

No additional

impact on

emissions

No

additional

impact on

emissions

DHDT capacity

enhancement The existing

stack is

constructed as

per CPCB

guidelines and

it is adequate

for marginal

changes in

stack emissions

due to the

DHDT capacity

enhancement.

Appropriate

storage tank,

equipment,

pumps, valve

seals and

packing

would be

specified

during

detailed

engineering.

The existing

facility is

constructed

as per CPCB

guidelines

and it is

adequate

for marginal

changes.

Only spent

catalysts are

the solid

waste

generated

from the

project. Spent

catalyst will be

collected and

disposed to

CPCB

approved

All rotary

equipment

shall be of

low noise

type.






recyclers.

CRU-MSQ revamp The existing

stack is

constructed as

per CPCB

guidelines and

it is adequate

for marginal

changes in

stack emissions

due to the

DHDT capacity

enhancement.

Appropriate

storage tank,

equipment,

pumps, valve

seals and

packing

would be

specified

during

detailed

engineering.

The existing

facility is

constructed

as per CPCB

guidelines

and it is

adequate for

marginal

changes.

Only spent

catalysts are

the solid waste

generated

from the

project. Spent

catalyst will be

collected and

disposed to

CPCB

approved

recyclers.

All rotary

equipment

shall be of

low noise

type.

Selective

Desulphurisation

(SDS) Unit

No stack

emission as

the Unit does

not have a

furnace

Appropriate

storage tank,

equipment,

pumps,

valve seals

and packing

would be

specified

during

detailed

engineering.

The liquid

effluent

generated

from the

process

(30.2

m3/hr.) will

be treated

in the

Waste

Water

Treatment

Plant

(WWTP)

and Tertiary

Treatment

Plant (TTP).

The treated

effluent will

be reused

to the

maximum

extent

possible to

reduce

discharge to

outside.

Only

equilibrium

catalysts /

spent

catalysts are

the solid

waste

generated

from the

project. Spent

catalyst will

be collected

and disposed

to CPCB

approved

recyclers.

All rotary

equipment

shall be of

low noise

type.

INDMAX Project The total SOx

and NOx

emissions as a

consequence

of the

proposed

project are

well within the

Appropriate

storage tank,

equipment,

pumps, valve

seals and

packing would

be specified

during

The liquid

effluent

generated

from the

process will

be treated in

the Waste

Water

Only

equilibrium

catalysts /

spent

catalysts are

the solid

waste

generated

All rotary

equipment

shall be of

low noise

type.






proposed

CPCB norms.

The stack

height will be

designed as

per CPCB

guideline, i.e. H = 14 x (Q)

0.3 or 60

meters,

whichever is

more (Q is the

Sulphur load)

detailed

engineering. Treatment

Plant

(WWTP) and

Tertiary

Treatment

Plant (TTP).

The treated

effluent will

be reused to

the maximum

extent

possible to

reduce

discharge to

outside.

from the

project.

Spent

catalyst will

be collected

and disposed

to CPCB

approved

recyclers.

2.8 Project Cost: Table no. 2.4: Project Cost

S.No Units Cost (INR in

Crores)

1 DHDT expansion 200

2 CRU expansion 610

3 INDMAX project 2500

4 SDS 33.4

5 Other BS-VI projects 842

Total 4185.4






CHAPTER 3






CHAPTER 3

DESCRIPTION OF ENVIRONMENT 3.1 Introduction

The reconnaissance survey of the area around the Indian Oil Corporation Limited plant was

carried out on 18th and 21st of November 2015 and the field studies were carried out for one

season (1st December 2015 to 1st March 2016) during post monsoon season for the EIA

studies to collect baseline primary and secondary data for the present environmental

scenario in the study area.

A comprehensive primary and secondary data collection program were undertaken to

assess the status of baseline environment conditions within the study area, as per the TOR

issued by MOEF&CC for carrying out the EIA/EMP study for one season from 1st December

2015 to 1st March 2016 during post monsoon season. The area covered by 10 km radius

around the project site has been considered for study.

The environmental monitoring has been carried out for ambient air quality, water quality,

soil characteristics, noise levels and meteorology.

Land, surface and ground water, soil, meteorology, ambient air, ambient noise constitute

the physical environment, while flora and fauna constitute the biological environment of the

study area. Demographic and socio-economic conditions of the study area were also studied

during the study period. Physical, biological and socio-economic environmental conditions

within 10 km radius study have been comprehensively discussed in the following sections.

3.2 Topography and Physiography

The topography of the study area is plain lands with few hill ranges on both banks of

Bramhaputra River which flows through the southern part.

Area near site is traversed by three meandering rivers viz., Aie, Tunia and Kujia. On the

Eastern side of the study area flows the river Aie in the South - East direction. The western

boundaries of the study area is having major tributaries of the river Brahmaputra

The plant site has ground elevation 55 m msl. Physiography and drainage Pattern of the area

is given in Figure 3.1.

3.3 Geology

Metamorphic complex with intrusive granite and pegmatite occur as isolated hillocks

surrounded by extensive alliuvium.






Age Formation

Recent to Pleistocene

(Quaternary Deposits)

Newer alluvium,

Older Alluvium

Piedmont sediments

Jurrasic

(Unconformity)

Dolerite, Pegmatite and quartz

Veins porphyritic granites

Gneissic complex, Graniteid Orthognesses, Mica

hornblend gneisses and Mignmatites

Archean Metamorphic Complex

(Unconformity)

Proxinites, Pyroxene granulites, Amphibolites and

hornblende Gneisses, Mica Schist, Muscovite,

Ferrugenenous quartzities, quartz magnetite

scists, magnetite quartzites.

3.4 Soil Characteristics

Physiographically, the district is divided into three units. The Older alluvium is represented

on northern border, followed by Younger alluvium in the middle part and the flood plain

zones in the southern part along the courses of River Brahmaputra and River Manas. The

northern piedmont zones attain the higher elevation while the flood plain or southern

border attains the lowest elevation. The altitude difference between the inselbergs and the

plain area is 20 - 460 m.

A number of perennial streams as tributaries of the River Brahmaputra flow through the

district. The principal rivers are Aie Kujia and Champavati. Among these tributaries, Aie is

the largest tributary and forms eastern boundary and the river Champavati forms the

western boundary of the district.

The soil of the district is broadly classified into three categories i.e. (1) Soil capping over

older alluvium is sandy, highly permeable, grayish brown in colour, (2) Soil on inselberg

zones are clayey, lateritic, yellowish to reddish in colour and (3) The soil of the flood plain

are sandy to silty loam and clayey loam in nature.

To understand the soil characteristics of the study area, 2 locations in the study area were

selected for soil sampling. The soil sampling locations are shown in Figure 3.3. Composite

sampling of soil upto root depth (10 – 15 cm) was carried out at each location.






Figure 3.1: Soil sampling locations

Table 3.1: Details of Soil Sampling Locations

Sr. no Name of sampling location Station code

1. Project premises S1

2. Mulgaon Chennarpara S2

The value of important physical and chemical parameters of these soil samples are given in

Table 3.2. From the tabulated values, the following conclusions can be made about the

physical and chemical characteristics of the soil samples.

Table : Soil Characteristics in the Study Area

Sn Parameters Unit S1 S2

pH 7.4 8.2

Conductivity mS/m 0.51 0.17

Texture Sandy loam Sandy loam

Water Holding Capacity % 32.7 41.2

Bulk Density gm/cc 1.42 1.51

Sodium meq/100g 4.7 3.9

Sulphate meq/100g 13.1 15

Calcium mg/100g 42.5 48.3

Magnesium mg/100g 78 90






Chloride meq/100g 14.2 13

Organic Carbon % 0.51 1.36

3.5 Water Resources and Water Quality

3.5.1 Water Resources

Water resources of the study area are classified into the following categories:

(i) Surface Water Resource: River, Nullah, Ponds, etc.

(ii) Ground Water Resources: Accumulation of water in deeper strata of ground.

The only source of recharging for surface water and ground water is from the

atmospheric precipitation, which is in the form of rainfall.

3.5.2 Surface Water Resources

Lakes Distances from

project site

(KM)

River Distances from

project site (KM)

Nayachara Lake 7 Aie 6

Bhosamari lake 9.2 Tunia 4

Paropota Lake 9.5 Kujia

7

Naodara 9.2

Kasorani 9.2

Major rivers which cut across the study area are Aie River, Tangainadi; Ghorabandha Nadi;

Ekanjani Nadi etc. Aie River which flows in North East directions of study area is major river

which is very dynamic and is slowly migrating its course from original inception when

observed the satellite imagery (Presence of Palaeo Channels and cut off meanders neary by

Aie River). Water spread area is changing the adjacent cropland/ Scrub land/ river sand

scenario. Area calculated for this category is 8.68 sq.km (2.85%).

3.5.3 Ground Water Resources

The estimated gross annual replenishable ground water resources of the district are 1430.21

mcm against net annual ground water draft of 577.66 mcm. The projected demand for

domestic and industrial uses up to 2025 is 28.84 mcm. The stage of ground water

development in the district is 43%

Hydrogeology

i) Major water bearing formation Sand, pebble, gravel formation

ii) Pre-monsoon water level 3.44 m

iii) Post Monsoon water level 3.04 m






iv) Long term water leveltrend (l997-

2007)

No significant change in water level is

observed.

3.5.4 Ground and Surface Water Quality

The quality of ground and surface water is influenced by surface and sub-surface

environmental conditions. The quantity and quality of water entering the underground

regime is another important parameter which influences underground water quality.

A. Water Sampling Locations

Water quality in the study area has been studied for assessing the water environment and

to evaluate anticipated impacts of the project. Based on the reconnaissance survey,

sampling locations were finalized keeping the following criteria as basis:

Figure 3.2: Water sampling locations






• Drainage pattern;

• Location of residential areas representing different activities/likely impact areas; and

• Likely areas which can represent baseline conditions

For assessing the ground water quality in the study area, water samples were collected from

four ground water locations from project site, Salbari pt., Bongaigaon Deoripara, Athugaon,

and Palashbhari and were analyzed as per the procedures specified in 'Standard Methods

for the Examination of Water and Wastewater' published by American Public Health

Association (APHA).

Two surface water samples were also collected from Aie River .i.e. one from downstream of

Choto Nilibari and other downstream of Chaprakata. The ground and surface water

sampling locations are shown in Figure 3.6. Ground water samples for chemical analysis

were collected in polyethylene carboys. Water samples collected for metal content were

acidified with 1 ml HNO3. Selected physico-chemical and heavy metal have been analyzed

for ground water quality status in the study area.

Table 3.2: Details of Ground and surface monitoring locations

Sr.no. Name of sampling location Station

code

1. Aie River

(downstream of Choto Nilibari)

SW 1

2. Aie River

(downstream of Chaprakata)

SW 2

3. Salbari pt. GW 1

4. Bongaigaon Deoripara GW 2

5. Athugaon GW 3

6. Palashbari GW 4

B. Characteristics of Ground Water Samples

The collected water samples were analyzed for physical and chemical parameters as

parameters described in IS:10500:2012. Table 3.3 gives desirable and permissible limits

prescribed for potable water in IS: 10500: 2012.






Table 3.3: Indian Standard Specification for Drinking Water

Sl.

No.

Characteristic Requirement

(Acceptable

Limit)

Permissible

Limit in the

Absence of

Alternate

Source

Protocol

I Organoleptic and Physical Parameters

i) Colour, Hazen units, Max 5 15 IS 3025 (Part 4)

ii) Odour Agreeable Agreeable IS 3025 (Part 5a)

iii) pH value 6.5-8.5 No relaxation IS 3025 (Part 11)

iv) Taste Agreeable Agreeable IS 3025 (Part

7&8)

v) Turbidity, NTU, Max 1 5 IS 3025 (Part 10)

vi) Total dissolved

solids, mg/l, Max

500 2000 IS 3025 (Part 16)

II General Parameters Concerning Substances Undesirable in Excessive

Amounts

i) Aluminium (as Al), mg/l,

Max

0.03 0.2 IS 3025 (Part 55)

ii) Ammonia (as total

ammonia-N), mg/l, Max

0.5 No relaxation IS 3025 (Part 34)

iii) Anionic detergents (as

MBAS) mg/l, Max

0.2 1.0 IS 13428

iv) Barium (as Ba), mg/l,

Max

0.7 No relaxation IS 15302

v) Boron (as B), mg/l, Max 0.5 1.0 IS 3025 (Part 57)

vi) Calcium (as Ca), mg/l,

Max

75 200 IS 3025 (Part 40)

vii) Chloramines (as Cl2),

mg/l, Max

4.0 No relaxation

IS

IS 3025 (Part 26)

viii) Chloride (as Cl), mg/l,

Max

250 1000 IS 3025 (Part 32)

ix) Copper (as Cu), mg/l,

Max

0.05 1.5 IS 3025 (Part 42)

x) Fluoride (as F) mg/l, Max 1.0 1.5 IS 3025 (Part 60)

xi) Free residual chlorine,

mg/l, Min

0.2 1 IS 3025 (Part 26)

xii) Iron (as Fe), mg/l, Max 0.3 No relaxation IS 3025 (Part 53)

xiii) Magnesium (as Mg),

mg/l, Max

30 100 IS 3025 (Part 46)

xiv) Manganese (as Mn),

mg/l, Max

0.1 0.3 IS 3025 (Part 59)

xv) Mineral oil, mg/l, Max 0.5 No relaxation IS 3025 (Part 39)






Sl.

No.


(Acceptable

Limit)

Permissible

Limit in the

Absence of

Alternate

Source

Protocol

xvi) Nitrate (as NO3), mg/l,

Max

45 No relaxation IS 3025 (Part 34)

xvii) Phenolic compounds (as

C6H5OH), mg/l, Max

0.001 0.002 IS 3025 (Part 43)

xviii) Selenium (as Se), mg/l,

Max


xix) Silver (as Ag), mg/l, Max 0.1 No relaxation IS 13428

xx) Sulphate (as SO4) mg/l,

Max

200 400 IS 3025 (Part 24)

xxi) Sulphide (as H2S), mg/l,

Max


xxii) Total alkalinity as

Calcium, mg/l, Max

200 600 IS 3025 (Part 23)

xxiii) Total hardness (as

CaCO3), mg/l, Max

200 600 IS 3025 (Part 21)

xxiv) Zinc (as Zn), mg/l, Max 5 15 IS 3025 (Part 49)

III Parameters Concerning Toxic Substances

i) Cadmium (as Cd), mg/l,

Max


ii) Cyanide (as CN), mg/l,

Max


iii) Lead (as Pb), mg/l, Max 0.01 No relaxation IS 3025 (Part 47)

iv) Mercury (as Hg), mg/l,

Max


v) Molybdenum (as Mo),

mg/l, Max


vi) Nickel (as Ni), mg/l, Max 0.02 No relaxation IS 3025 (Part 54)

vii) Polychlorinated

biphenyls, mg/l, Max

0.0005 No relaxation APHA 6630

viii) Polynuclear aromatic

hydrocarbons (as PAH),

mg/l, Max

0.0001 No relaxation APHA 6630

ix) Total Arsenic (as As),

mg/l, Max

0.01 0.05 IS 3025 (Part 37)

x) Total chromium (as Cr),

mg/l, Max

0.05 No relaxation IS 3025 (Part 52

xi) Trihalomethanes






Sl.

No.


(Acceptable

Limit)

Permissible

Limit in the

Absence of

Alternate

Source

Protocol

a) Bromoform, mg/l, Max 0.1 No relaxation ASTM D 3973-85

or

APHA 6232

b) Dibromochloromethane,

mg/l, Max

0.1 No relaxation ASTM D 3973-85

or

APHA 6232

c) Bromodichloromethane,

mg/l, Max

0.06 No relaxation

ASTM D 3973-85

or

APHA 6232

d) Chloroform, mg/l, Max 0.2 No relaxation ASTM D 3973-85

or

APHA 6232

IV Bacteriological Quality of Drinking Water

i All water intended for

drinking,

a) E. coli or

thermotolerant coliform

bacteria (TCB)

Shall not be detectable in

any 100 ml sample

Source: Bureau of Indian Standard Code IS: 10500:2012.

The results of ground water analysis are given in Table 3.4.

Colour: The colour of ground water sample was found to be <5 hazen unit.

Odour: The odour of ground water sample is agreeable and meets the desirable limit for

drinking water standard.

pH: The pH value of ground water river water sample is 6.8 to 7.5 and always meets the

drinking water desirable standard.

Total Dissolved Solids (TDS): TDS of ground water is 126 to 281 mg/l.

Total Hardness: Total hardness value ground water sample is 38 to 122 mg/l.

Iron: The iron content in ground water sample is 0.01 to 0.12 mg/l and found within the

permissible limit of 0.3 mg/l in the absence of alternate source of potable water.

Chloride: Chloride content of ground water sample is 12 to 48 mg/l and meets the

acceptable limit of 250 mg/l.






Calcium: Calcium content in ground water 10.2 to 20.5 mg/l and found within the


Magnesium: Magnesium content in ground water sample is 24 to 50 mg/l and found within

the acceptable limit of 75 mg/l.

Sulphate: Sulphate content in ground water river water sample is 30 to 81 mg/l and meets

the acceptable limit of 200 mg/l for potable water.

Nitrate: Nitrate content in ground water is 1.8 to 4.8 mg/l and meets the acceptable limit of

45 mg/l for potable water.

Fluoride: Fluoride content of water sample is < 0.1mg/l and meets the acceptable limit of 1

mg/l for potable water.

Conclusions: The results of ground water were compared to Indian Standard Specification of

drinking water IS: 10500:2012.


enhancement from 1.2 to 1.8 MMTPA, CRU-MSQ revamp & implementation of SDS unit by M/s IOCL, Bongaigaon Refinery at Dhaligaon, Dist: Chirang

(BTAD), Assam


Table 3.4: Ground Water Quality in the Study Area

Sn. Parameters Units Salbari pt. Bongaigaon

Deoripara Athugaon Palashbari

1. pH 6.8 7.1 7.5 6.9

2. Colour Hazen <5 <5 <5 <5

3. Odour Agreeable Agreeable Agreeable Agreeable

4. Turbidity NTU 3 1 4 2

5. TDS mg/l 126 263 281 155

6. Hardness as CaCO3 mg/l 122 38 90 68

7. Nitrate as NO3 mg/l 1.8 3.6 4.8 3.7

8. Chloride as Cl mg/l 12 36 48 44

9. Sulphate as SO4 mg/l 30 70 67 81

10 Calcium as Ca mg/l 20.5 10.2 13.7 19.6

11. Magnesium as Mg mg/l 24 50 62 42

12. Iron as Fe mg/l 0.01 0.08 0.12 0.04

13. Fluoride as F mg/l <0.1 <0.1 <0.1 <0.1

14. Total Alkalinity as CaCO3 mg/l 30.7 85.3 70.6 60.2

15. Zinc as Zn mg/l 0.22 0.18 0.13 0.24

16. Copper as Cu mg/l <0.02 <0.02 <0.02 <0.02

17. Cyanide as CN mg/l <0.02 <0.02 <0.02 <0.02

18. Arsenic as As mg/l <0.005 <0.005 <0.005 <0.005

19. Mercury as Hg mg/l <0.001 <0.001 <0.001 <0.001

20. Lead as Pb mg/l <0.05 <0.05 <0.05 <0.05

21. Chromium as Cr+6 mg/l <0.05 <0.05 <0.05 <0.05

Note: BDL indicates Below Detection Limit.






B. Characteristics of Surface Water Samples

The surface water samples were collected from Aie River and analyzed for physical and

chemical parameters. Table 3.5 gives analyzed results for Aie River and discussed below:

Colour: The colour of surface water samples was found to be 5 hazen unit.

Odour: The odour of surface water samples is agreeable and meets the desirable limit for

drinking water standard.

pH: The pH value of the surface water samples is 6.9 and 7.01 meeting the drinking water

desirable standard.

Total Dissolved Solids (TDS): TDS of surface water sample is 20 and 31 mg/l and meets

permissible limit of 500 mg/l.

Total Hardness: Total hardness value surface water sample is 190 and 185 mg/l Hardness

value is within the acceptable limit of 200 mg/l.

Iron: The iron content in surface water sample is 1.09 and 0.94 mg/l and found within the

permissible limit of 0.3 mg/l in the absence of alternate source of potable water.

Chloride: Chloride content of surface water sample is 9.1 and 4.3 mg/l and meets the


Calcium: Calcium content in surface water sample is 7.09 and 8.46 mg/l and found within

the acceptable limit of 75 mg/l.

Magnesium: Magnesium content in surface water sample is 1.44 and 4.55 mg/l and found

within the acceptable limit of 75 mg/l.

Total Alkalinity: Total alkalinity of surface water sample is 39.5 and 60.75 mg/l and meets

within the permissible limit 600 mg/l.

Sulphate: Sulphate content in surface water sample is 7.59 and 4.91 mg/l and meets the

acceptable limit of 200 mg/l for potable water.

Nitrate: Nitrate content in surface water sample is 0.10and 0.15 mg/l and meets the

acceptable limit of 45 mg/l for potable water.

Fluoride: Fluoride content of surface water sample is < 0.1 mg/l and meets the acceptable

limit of 1 mg/l for potable water.






Table 3.5: Analysis Results of Aie River Water

Sn. Parameters Unit SW1 SW2

1. Colour Hazan 5 5

2. pH -- 6.9 7.01

3. Total Dissolved Solids mg/l 20 31

4. Total Hardness mg/l 190 185

5. Iron (Fe) mg/l 1.09 0.94

6. Chloride (Cl) mg/l 9.1 4.3

7. Calcium (Ca) mg/l 7.09 8.46

8. Magnesium (Mg) mg/l 1.44 4.55

9. Copper (Cu) mg/l <0.02 <0.02

10. Manganese (Mn) mg/l 0.07 0.03

11. Sulphate (SO4) mg/l 7.59 4.91

12. Nitrate (NO3) mg/l 0.10 0.15

13. Fluoride (F) mg/l <0.1 <0.1

14. Phenolic Compounds mg/l <0.001 <0.001

15. Mercury (Hg) mg/l <0.001 <0.001

16. Cadmium (Cd) mg/l <0.1 <0.1

17. Selenium (Se) mg/l <0.01 <0.01

18. Arsenic (As) mg/l <0.005 <0.005

19. Cyanide (CN) mg/l <0.02 <0.02

20. Lead (Pb) mg/l <0.05 <0.05

21. Zinc (Zn) mg/l <0.02 <0.02

22. Anionic Detergents mg/l <0.05 <0.05

23. Pesticides mg/l <0.01 <0.01

24. Alkalinity as CaCO3 mg/l 39.5 60.75

25. Aluminum (as Al) mg/l <0.01 <0.01

26. DO mg/l 7.3 7.5

27. BOD mg/l <1 <1

28. COD mg/l 9.1 5

3.6 Climatology and Meteorology

3.6.1 Introduction

The meteorological parameters play a vital role in transport and diffusion of pollutants in

the atmosphere. The collection and analysis of meteorological data, therefore, is an

essential component of environmental impact assessment studies. The long term and short

term impact assessment could be made through utilization and interpretation of

meteorological data collected over long and short periods, respectively.






3.6.2 Climatology

Climatological (long-term) data is obtained from the closest Indian Meteorology Department

(IMD) station or from any other nearby station, which has been collecting meteorological

data for more than ten years. Climatological data for the site was obtained from Goalpara

IMD station, which is at an aerial distance of 40 KM from Bongaigaon and the same is

discussed in Subsection 3.6.3.

3.6.3 Climatological Data

A. Seasons

The climate of Assam is characterized by alternate cool and warm periods with a high

humidity, Especially from May to November. Between March and May at the time when

precipitation in Northern India is at the minimum, Assam gets some amount of rainfall from

the Norwesters which keep the temperature low in the season of spring.

B. Temperature

The winter season starts from December and continues till the end of February. January is

the coolest month. The mean daily maximum temperature during winter season is 24.6 °C

(in the month of December) and the mean daily minimum temperature at 11.5 °C (in the

month of December). 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 31.5°C with the minimum

temperature (March) at 15.5°C. The mean maximum temperature in the monsoon season

was observed to be 31.4°C in the month of June. By the end of August the day temperatures

increase slightly, with the mean maximum temperature at 31.7°C in the month of

September and the night temperature decreases with the mean minimum temperatures at

9.8°C in the month of January.






Figure 3.3: Monthly Relative Temperature

C. Relative Humidity:

The air is generally humid in this region during the monsoon reason when the maximum

relative humidity at 0830 hr was observed to be 87%. Similarly, at 1730 hr, the minimum

relative humidity was observed to be 48%. Generally, the weather during other seasons was

observed to be dry.

Figure 3.4: Monthly Relative Humidity

D. Atmospheric Pressure

The maximum pressure occurring during the winter season, in the month of January and

December.The maximum pressure were observed in month of December 1011.6 mb at 0830

hr and 1007.6 mb at 1730 hr. The minimum pressure observed were 996.3 mb at 0830 and

993 mb at 1730 hr, with minimum pressure occurring during the month of June in the

monsoon season.

The average pressure level in was to be 1004.1 mb at 0830 hrs and 1000 mb at 1730 hr. It

can be seen from the data that not many variations are observed in the average

atmospheric pressure levels. The pressure levels are found to be fairly consistent over the

region.

E. Rainfall

The district receives heavy rainfall of 3219.1 mm in an average under the influence of south

west monsoon' In general, the temperature of the atmosphere varies from 12 to 36ºc

throughout the year. Humidity is high ranging upto 80-90 % during rainy season.

The climate of the district is characterized by high rainfall and sub-humid-climate. The

annual rainfall of 3,219 mm is distributed throughout the year from the month of April to






October. The maximum rainfall occurs during the month of July-August, December and

January are the driest months generally. Humidity of air is very high observed during the

month of July

Table 3.10: Summary of Micro meteorological Conditions near the site

Parameter Post Monsoon Season

Temperature

Max (oC)

Min (oC)

32.9

5.1

Relative Humidity

Max (%)

Min (%)

76 %

64 %

Wind Speed

Max (kmph)

Min (kmph)

Mean (kmph)

8.3

2.3

4.1

Calm Period (%) 32.1

Predominant Wind Flow Direction towards E, ENE, NE directions



(BTAD), Assam


Climatological Table (30 Years meteorological Data: Year 1951 to 1980), IMD Station: Goalpara

Air Temperature

MONTH

STATION

LEVEL

PRESSURE

MEAN EXTREMES HUMIDITY

DRY

BULB

WET

BULB

DAILY

MAX

DAILY

MIN

HIGHEST IN

THE

MONTH

LOWEST IN

THE

MONTH

HIGHEST

DATE &

YEAR

LOWEST

DATE &

YEAR

RELATIVE

HUMIDITY

VAPOUR

PRESSURE

MPA °C °C °C °C °C °C °C °C % hPa

JAN I 1011.5 15.4 14.0 23.6 9.8 26.0 6.8 28.4 07 3.0 30 86 15.0

II 1007.3 18.7 15.8 1958 1964 72 15.6

FEB I 1008.9 18.0 15.2 26.4 11.5 30.4 7.6 32.4 21 5.3 04 73 15.1

II 1004.5 22.5 16.9 1976 1968 55 14.7

MAR I 1006.3 22.4 18.1 30.2 15.5 35.2 11.2 38.6 27 4.5 11 65 17.3

II 1001.5 26.8 19.3 1979 1979 48 16.3

APR I 1000.3 25.4 21.5 31.5 20.0 36.3 15.9 39.5 30 10.3 01 71 22.6

II 995.8 28.6 22.4 1960 1968 58 22.1

MAY I 996.4 26.5 23.8 31.0 22.5 35.5 19.1 40.3 01 10.4 03 79 27.2

II 992.8 28.9 24.7 1960 1975 71 27.6

JUN I 996.0 27.8 25.7 31.4 24.7 34.9 22.2 38.5 06 20.6 01 84 31.3

II 993.7 29.0 26.2 1979 1979 79 31.6

JUL I 997.3 28.4 23.3 31.8 25.5 34.7 23.7 36.7 10 21.6 08 85 32.6

II 993.6 29.4 26.7 1979 1978 80 32.8

AUG I 1001.1 28.6 26.4 32.1 23.3 34.8 23.5 36.3 25 22.3 21 84 32.7

II 997.2 29.2 26.6 1973 1978 81 32.6

SEP I 1001.1 28.2 25.9 31.7 24.6 34.5 22.6 35.9 05 21.2 08 83 31.6

II 997.2 28.3 25.9 1957 1959 82 31.4

OCT I 1006.1 26.0 23.8 30.1 21.8 32.9 18.2 34.5 01 13.8 31 83 27.7

II 1002.1 26.6 24.3 1980 1979 82 28.6

NOV I 1009.8 21.5 19.7 27.4 16.4 29.9 12.6 32.5 03 10.0 22 84 21.6

II 1005.9 22.6 20.5 1957 1965 82 22.6

DEC I 1011.6 17.1 15.7 24.6 11.5 27.0 8.5 30.9 18 4.9 28 87 16.9

II 1007.6 19.1 17.1 1957 1969 80 17.9

Annual Total 1004.1 23.8 21.3 29.3 19.1 37.0 6.5 40.3 3.0 80 24.3

Mean 1000.0 25.8 22.2 73 24.5

I - 08.30 HOURS IST : II - 17.30 HOURS IST



(BTAD), Assam


RAINFALL CLOUD AMOUNT

MONTH

STATION

LEVEL

PRESSURE

MONTHLY

TOTAL

NO. OF RAINY

DAYS

TOTAL IN

WETTEST

MONTH WITH

YEAR

TOTAL IN

DRIEST

MONTH WITH

YEAR

HEAVIEST

FALL IN 24

HOURS

DATE AND

YEAR

ALL CLOUDS

LOW CLOUDS

MEAN WIND

SPEED

(MPa) (mm) (mm) (mm) (mm) (Oktas of Sky) (Km/hr)

JAN I 1011.5 11.4 1.2 65.7 0.0 39.1 10 2.2 1.0 2.5

II 1007.3 1957 1957 2.8 0.9

FEB I 1008.9 12.8 1.3 46.6 0.0 34.0 24 1.9 0.8 3.7

II 1004.5 1980 1980 2.8 1.2

MAR I 1006.3 57.7 4.6 176.1 4.6 49.8 22 2.4 0.9 5.1

II 1001.5 1953 1957 1955 2.2 1.4

APR I 1000.3 142.3 9.0 413.3 34.1 100.3 30 3.7 2.0 8.3

II 995.8 1977 1960 1955 3.9 2.1

MAY I 996.4 248.0 14.3 424.6 62.6 96.8 12 5.6 3.3 5.7

II 992.8 1952 1969 1958 4.5 2.6

JUN I 996.0 350.1 16.1 593.7 122.4 194.3 05 6.6 4.0 4.6

II 993.7 1956 1967 1956 6.2 3.4

JUL I 997.3 353.6 16.8 646.7 180.7 131.6 12 7.0 4.3 4.3

II 993.6 1977 1962 1970 6.4 3.7

AUG I 1001.1 269.9 13.9 393.9 70.6 129.2 29 6.7 3.8 4.2

II 997.2 1950 1979 1960 6.2 3.6

SEP I 1001.1 166.2 10.3 405.2 27.2 90.2 16 5.9 3.4 3.7

II 997.2 1953 1962 1966 5.9 3.3

OCT I 1006.1 79.2 5.3 261.4 20.2 60.9 01 4.5 2.9 3.4

II 1002.1 1651 1967 1974 4.2 2.4

NOV I 1009.8 19.4 1.5 81.5 0.0 38.5 23 3.3 2.1 2.9

II 1005.9 1971 1966 3.0 1.5

DEC I 1011.6 5.1 0.4 36.6 0.0 35.3 10 2.5 1.3 2.3

II 1007.6 1973 1973 2.7 0.9

Annual Total 1004.1 1717.7 94.7 2476.6

1977

1452.2

1975

194.3 4.4

4.3

2.5

2.3

4.1

Mean 1000.0

I - 08.30 HOURS IST : II - 17.30 HOURS IST

Table: Climatological Table (30 Years meteorological Data: Year 1951 to 1980), IMD Station: Goalpara






Wind speed and direction

The data for wind speed and direction were recorded every hour round the clock during the

winter season. The wind rose diagrams for 01 to 24 hrs, during daytime and during night

time based on wind data monitored for the study period (winter season) are presented

separately in Figures 4.1a, 4.1b and 4.1c respectively.

During the study period the predominant wind directions were observed from E (10.4%),

ENE (6.25%), and NE (3.9%) with wind speed ranging from 1.8 to 7.2 km/hr. The calm period

observed during this season was found to be 67%.

Wind Rose Diagram:

Calm Wind : 67 %

Location: BGR-IOCL, Assam

Start Time: 01/12/15, 21:00

End Time: 01/03/16, 5:00

Note: Frequencies indicate the direction from where the wind is blowing






Wind Rose Diagram:

Calm Wind : 52.9 %


Start Time: 01/12/15, 06:00

End Time: 01/03/16, 20:00







Wind Rose Diagram:

3.6.4 Micro Meteorological Data for the Site

The meteorological data, such as, wind speed and direction, ambient temperature, and

relative humidity was collected near the IOCL plant at Bongaigaon and is presented in Table

3.10 for post monsoon season.

3.7 Ambient Air Quality

3.7.1 Introduction

To study the baseline air quality scenario in the study area, six ambient air quality

monitoring (AAQM) stations were selected in the study area in different directions and at

different distances from the project site keeping in view of the guidelines of the Ministry of

Environment, Forest and Climate Change (MOEF&CC).

Calm Wind : 90.6 %


Start Time: 01/12/15, 06:00

End Time: 01/03/16, 20:00







Figure 3.5: Air sampling locations

3.7.2 Methodology of Monitoring and Analysis

Envirotech APM 460 BL Respirable Dust Sampler (RDS) and Sampler (Envirotech APM

550)/Ecotech (AAS 127) fine particulate matter were deployed for ambient air quality

monitoring.

The baseline data of air environment is monitored for the below mentioned parameters:

• Particulate Matter (PM2.5);

• Particulate Matter (PM10);

• Sulphur dioxide (SO2);

• Di oxides of Nitrogen (NO2);

• Ozone (O3);

• Lead (Pb);






• Carbon Monoxide (CO);

• Ammonia (NH3);

• Benzene (C6H6);

• Benzo (a) Pyrene (BaP);

• Arsenic (As);

• Nickel (Ni),

3.7.3 Sampling and Analytical Techniques

PM2.5 and PM10 have been estimated by gravimetric method. Modified West and Gaeke

method (IS-5182 part-II, 1969) have been adopted for estimation of SO2. Jacobs-Hochheiser

method (IS-5182 part-IV, 1975) has been adopted for the estimation of NO2.

Samples for carbon monoxide were analyzed using NDIR techniques. The techniques

adopted for sampling and analysis are given in Table 3.11 along with the minimum

detection limits for each parameter.

Table 3.11: Techniques Used For Ambient Air Quality Monitoring

S.

No. Parameter Technique

Detectable

Limit (µg / m

3)

1 Particulate Matter (PM10) Gravimetric [EPA -40 (CFR Part 50)] 2.0

2 Particulate Matter

(PM2.5) Gravimetric [EPA -40 (CFR Part 50)] 2.0

3 Sulphur Dioxide (SO2) Improved West and Gaeke 5.0

4 Nitrogen Dioxide (NO2) Modified Jacob & Hochheiser 5.0

5 Carbon Monoxide (CO) NDIR [IS 13270 : 1992] 0.1

6 Ammonia (NH3) Nesslers Method (APHA) 20

7 Ozone (O3) KI Absorption Method 5.0

8 Lead (Pb) AAS Method [IS 5182 (Part 22) : 2004] 0.1

9 Arsenic (As) AAS Method [IS 5182 (Part 22) : 2004] 0.001

10 Nickel (Ni) AAS Method [IS 5182 (Part 22) : 2004] 0.001

11 Benzone (C6H6) Adsorption & Desorption followed by

GC [IS 5182 (Part 11) : 2006] 0.01

12 Benzo (a) pyrene (BaP) Solvent Extraction followed by GC

Analysis [IS 5282 (Part 12) : 1991] 0.00






3.7.4 Ambient Air Quality Monitoring Locations

The Premises of IOCL, Sukinapara, Baikhungaon, Madarpur, Namalpur, Dabli, Barshangaon

and Chitkagaon were selected for ambient air quality monitoring based as per guidelines of

CPCB. Ambient air quality monitoring locations are shown in Figure 3.11.

3.7.5 National Ambient Air Quality Standards

The national ambient air quality standards are given in Table 3.12. Monitored values for

study have been compared with the National Ambient Air Quality Standards.






3.7.6 Results of Ambient Air Quality Monitoring

The results of monitoring of PM2.5, PM10, SO2, NO2, NH3, O3, C6H6, BaP, Pb, As, Ni and CO

concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur, Namalpur, Dabli,

Barshangaon,and Chitkagaon during the post-monsoon season are presented in Table 3.13

to Table 3.18. On the basis of tabulated data following observations can be made:

Fine Particulate Matter (PM2.5)

The 24-hourly PM2.5 concentrations Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,

Namalpur, Dabli, Barshangaon, and Chitkagaon AAQM locations vary in the range of 20.0 to

50 µg/m3. The maximum PM2.5 concentration was found 43 µg/m3 while minimum PM2.5

concentration was 20 µg/m3. The mean PM2.5 concentration was 38.2 µg/m3 and 98% tile

value of PM2.5 concentration was found 43.5 µg/m3

Particulate Matter (PM10)

The 24-hourly PM10 concentrations Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,

Namalpur, Dabli, Barshangaon,and Chitkagaon AAQM locations during post-monsoon

season vary in the range of 40 µg/m3 to 90 µg/m3. The maximum PM10 concentration was

found 90 µg/m3 while minimum PM10 concentration was 41 µg/m3. The mean PM10

concentration was 77.9 µg/m3 and 98%tile value of PM10 concentration was 90 µg/m3.

Sulphur Dioxide (SO2)

The 24-hourly SO2 concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,


season vary in the range of 4 to 10 µg/m3. The maximum SO2 concentration was found 9.0

µg/m3 while minimum SO2 concentration was 4.2 µg/m3. The mean SO2 concentration was

6.39 µg/m3 and 98%tile value of SO2 concentration was 8.15 µg/m3.

Nitrogen Oxide (NO2)

The 24-hourly NO2 concentration at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,


season varies in the range of 15.0 to µg/m3. The maximum NO2 concentration was found as

43.0 µg/m3 and minimum NO2 concentration was15.0 µg/m3. The mean NO2 concentration

was 34.0 µg/m3 and 98%tile value of NO2 concentration was 41.5 µg/m3.

Ammonia (NH3)

The NH3 concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,

Namalpur, Dabli, Barshangaon,and Chitkagaon AAQM locations were found less than 5.0

µg/m3 during post-monsoon season.

Ozone (O3)

The Ozone concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,








Benzene (C6H6)

The C6H6 concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,


µg/ m3 during post-monsoon season.

Benzo (a) Pyrene (BaP)

The BaP concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,

Namalpur, Dabli, Barshangaon,and Chitkagaon AQM locations were found less than 0.01

ng/m3 during post-monsoon season.

Lead (Pb)

The Lead concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,



Carbon Monoxide (CO)

The 8-hourly CO concentration at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,


season aries in the range of 0.2 to 0.6 mg/m3 The maximum CO concentration was found as

0.56 mg/m3 and minimum CO concentration was 0.2 mg /m3 The mean CO concentration

was 0.43 mg/m3 and 98%tile value of CO concentration was 0.56 mg/m3.

Arsenic (As)

The Arsenic concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,


ng/m3 during post-monsoon season.

Nickel (Ni)

The Nickel concentrations at Premises of IOCL, Sukinapara, Baikhungaon, Madarpur,

Namalpur, Dabli, Barshangaon,and Chitkagaon AAQM locations were found less than 1.0 ng/

m3 during post-monsoon season.

3.7.7 Ambient Air Quality Status

National ambient air quality standards are given in Table 3.13. National ambient air quality

standards for industrial, residential, rural & other areas are met for all monitored

parameters at all AAQM locations during post monsoon season.

Table 3.12: National Ambient Air Quality Standards

S.No Pollutant Time Weighted

Average

Concentration in Ambient Air

Industrial

Residential,

Rural & Other

Areas

Ecologically

Sensitive Area

(Notified by Central

Government)

1. Sulphur dioxide Annual Average* 50 20






S.No Pollutant Time Weighted

Average

Concentration in Ambient Air

Industrial

Residential,

Rural & Other

Areas

Ecologically

Sensitive Area

(Notified by Central

Government)

(SO2)(µg/m3) 24 Hours** 80 80

2. Oxides of Nitrogen

(NOx) (µg/m3)

Annual Average* 40 30

24 Hours** 80 80

3. Particulate Matter

(Size Less Then 10

µm) or PM10 (µg/m3)


24 Hours** 100 100

4. Particulate Matter

(Size Less Then 2.5

µm) or PM2.5 (µg/m3)


24 Hours** 60 60

5. Ozone O3 (µg/m3) 8 Hours* 100 100

1 Hours** 80 80

6. Lead (Pb) (µg/m3) Annual Average* 0.5 0.5

24 Hours** 1.0 1.0

7. Carbon monoxide

(CO) (mg/m3) Annual Average* 2 2

24 Hours** 4 4

8. Ammonia (NH3)

(µg/m3)


24 Hours** 400 400

9. Benzene (C6H6)

(µg/m3)

Annual* 5 5

10. Benzo (a) Pyrane

(BaP) particulate

phase only (ng/m3)

Annual* 1 1

11. Arsenic (As) (ng/m3) Annual* 6 6

12. Nickel (Ni) (ng/m3) Annual* 20 20

Note:

* Annual arithmetic mean of minimum 104 measurements in a year taken twice a week 24

hourly at uniform interval.

** 24 hourly /8 hourly values should be met 98% of the time in a year. However 2% of the

time, it may exceed but not on two consecutive days.



(BTAD), Assam


Table 3.13 : Ambient Air Quality at Project Site (AAQM1)

S. No. Date PM2.5 PM10 SO2 NO2 CO NH3 O3 Pb C6H6 BaP (C20H12) As Ni

µg/m3 µg/m

3 µg/m

3 µg/m

3 mg/m

3 µg/m

3 µg/m

3 µg/m

3 µg/m

3 ng/m

3 ng/m

3 ng/m

3

1 02.12.2015 24 75 7.2 27 0.43 <5.0 0.00 <0.1 <0.1 <0.01 <1.0 <1.0

2 03.12.2015 37 69 6.5 36 0.39 <5.0 0.00 <0.1 <0.1 <0.01 <1.0 <1.0

3 07.12.2015 22 85 4.5 23 0.49 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

4 08.12.2015 26 88 4.9 27 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

5 14.12.2015 25 70 5.6 30 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

6 15.12.2015 30 65 7.5 29 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

7 21.12.2015 25 62 8.8 29 0.31 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

8 22.12.2015 27 60 7.5 29 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

9 28.12.2016 38 81 4.8 35 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

10 29.12.2016 24 66 6.2 24 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

11 04.01.2016 23 85 6.8 30 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

12 05.01.2016 35 75 6.5 21 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

13 11.01.2016 29 75 5.5 32 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

14 12.01.2016 21 85 7.2 24 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

15 18.01.2016 32 88 6.6 22 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

16 19.01.2016 42 67 5.8 26 0.52 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

17 25.01.2016 35 89 4.2 28 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

18 26.01.2016 38 66 4.5 28 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

19 01.02.2016 39 84 5.5 28 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

20 02.02.2016 35 69 5.8 35 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

21 08.02.2016 43 78 5.7 28 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

22 09.02.2016 40 89 5.1 28 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

23 15.02.2016 38 66 4.5 39 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

24 16.02.2016 38 80 6.5 22 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

25 22.02.2016 30 85 6.8 33 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

26 23.02.2016 40 90 5.5 20 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Minimum 21 60 4.2 20 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Maximum 43 90 8.8 39 0.31 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Average 32.14 76.5 6.04 28.29 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

98 %tile 42.5 89.5 8.15 37.5 0.54 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0



(BTAD), Assam


Table 3.14 : Ambient Air Quality (AAQM2)

S.

No.

Date PM2.5

µg/m3

PM10

µg/m3

SO2

µg/m3

NO2

µg/m3

CO

mg/m3

NH3

µg/m3

O3

µg/m3

Pb

µg/m3

C6H6

µg/m3

BaP (C20H12)

ng/m3

As

ng/m3

Ni

ng/m3

1 02.12.2015 42 82 8.0 35 0.44 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

2 03.12.2015 40 88 8.0 30 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

3 07.12.2015 42 89 7.0 35 0.49 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

4 08.12.2015 38 83 5.0 29 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

5 14.12.2015 35 75 6.0 28 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

6 15.12.2015 34 89 8.0 33 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

7 21.12.2015 31 88 6.0 43 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

8 22.12.2015 36 89 4.2 32 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

9 28.12.2016 34 81 6.0 35 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

10 29.12.2016 31 75 8.0 40 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

11 04.01.2016 33 67 4.3 27 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

12 05.01.2016 40 66 6.0 28 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

13 11.01.2016 43 85 7.0 32 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

14 12.01.2016 38 83 8.0 27 0.44 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

15 18.01.2016 41 68 4.2 26 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

16 19.01.2016 42 83 5.0 37 0.52 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

17 25.01.2016 42 75 8.0 36 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

18 26.01.2016 23 85 8.0 37 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

19 01.02.2016 39 68 4.5 38 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

20 02.02.2016 35 74 7.0 39 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

21 08.02.2016 40 78 5.0 28 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

22 09.02.2016 36 76 6.0 22 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

23 15.02.2016 38 72 6.0 31 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

24 16.02.2016 32 64 4.5 38 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

25 22.02.2016 31 84 8.0 36 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

26 23.02.2016 39 70 6.0 25 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Maximum 43 89 8 43 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Minimum 23 64 4.2 22 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Average 36.7 78.3 6.3 32.6 0.44 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

98 %tile 42.5 89 8 41.5 0.54 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0



(BTAD), Assam



S.

No.

Date PM2.5 PM10 SO2 NO2 CO NH3 O3 Pb C6H6 BaP (C20H12) As Ni

µg/m3 µg/m3 µg/m3 µg/m3 mg/m3 µg/m3 µg/m3 µg/m3 µg/m3 ng/m3 ng/m3 ng/m3

1 02.12.2015 39 82 8.0 35 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

2 03.12.2015 36 88 8.0 30 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

3 07.12.2015 38 89 7.0 35 0.49 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

4 08.12.2015 42 83 5.0 29 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

5 14.12.2015 43 75 6.0 28 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

6 15.12.2015 41 89 8.0 33 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

7 21.12.2015 30 88 6.0 43 0.31 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

8 22.12.2015 34 89 4.2 32 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

9 28.12.2016 44 81 6.0 35 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

10 29.12.2016 40 75 8.0 40 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

11 04.01.2016 42 67 4.3 27 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

12 05.01.2016 42 66 6.0 28 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

13 11.01.2016 43 85 7.0 32 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

14 12.01.2016 38 83 8.0 27 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

15 18.01.2016 35 68 4.2 26 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

16 19.01.2016 41 83 5.0 37 0.52 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

17 25.01.2016 38 75 8.0 36 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

18 26.01.2016 40 85 8.0 37 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

19 01.02.2016 34 68 4.5 38 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

20 02.02.2016 36 74 7.0 39 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

21 08.02.2016 41 78 5.0 28 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

22 09.02.2016 38 76 6.0 22 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

23 15.02.2016 30 72 6.0 31 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

24 16.02.2016 40 64 4.5 38 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

25 22.02.2016 34 84 8.0 36 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

26 23.02.2016 35 70 6.0 25 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Maximum 44 64 4.2 22 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Minimum 30 89 8.0 43 0.31 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Average 38.2 78.2 6.28 32.57 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

98 %tile 43.5 88 8 41.5 0.54 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0



(BTAD), Assam


Table 3.16: Ambient Air Quality (AAQM4)

S.

No.


µg/m3 µg/m3 µg/m3 µg/m3 mg/m3 µg/m3 µg/m3 µg/m3 µg/m3 ng/m3 ng/m3 ng/m3

1 02.12.2015 39 78 4.6 34 0.40 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

2 03.12.2015 36 72 4.5 40 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

3 07.12.2015 38 85 7.0 22 0.49 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

4 08.12.2015 42 88 7.0 23 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

5 14.12.2015 43 87 4.2 38 0.50 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

6 15.12.2015 41 68 4.5 35 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

7 21.12.2015 30 86 6.0 30 0.32 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

8 22.12.2015 34 90 8.0 37 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

9 28.12.2016 44 72 8.0 38 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

10 29.12.2016 40 64 4.2 17 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

11 04.01.2016 42 88 5.0 23 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

12 05.01.2016 42 90 8.0 35 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

13 11.01.2016 43 76 8.0 30 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

14 12.01.2016 38 86 6.0 31 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

15 18.01.2016 35 76 5.0 20 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

16 19.01.2016 41 88 6.0 18 0.55 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

17 25.01.2016 38 62 6.0 39 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

18 26.01.2016 40 88 8.0 34 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

19 01.02.2016 34 61 8.0 23 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

20 02.02.2016 36 88 8.0 35 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

21 08.02.2016 41 86 5.0 40 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

22 09.02.2016 38 85 8.0 39 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

23 15.02.2016 30 77 7.0 15 0.45 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

24 16.02.2016 40 69 6.0 36 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

25 22.02.2016 34 55 6.0 19 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

26 23.02.2016 35 72 7.0 39 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Minimum 30 55 4.2 15 0.32 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Maximum 44 90 9.0 40 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Average 38.1 77.9 6.39 34 0.4 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

98 %tile 43.5 90 8 40 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0



(BTAD), Assam



S.

No.


µg/m3 µg/m

3 µg/m

3 µg/m

3 mg/m

3 µg/m

3 µg/m

3 µg/m

3 µg/m

3 ng/m

3 ng/m

3 ng/m

3

1 04.12.2015 29 65 6.2 24 0.27 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

2 05.12.2015 20 82 4.8 37 0.36 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

3 09.12.2015 43 41 5.5 21 0.23 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

4 10.12.2015 34 59 6.1 40 0.27 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

5 16.12.2015 25 61 5.8 18 0.30 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

6 17.12.2015 24 64 5.1 25 0.29 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

7 23.12.2015 36 83 4.9 30 0.29 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

8 24.12.2015 36 75 4.2 25 0.29 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

9 30.12.2016 24 59 4.1 19 0.35 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

10 31.12.2016 39 81 4.9 35 0.24 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

11 06.01.2016 21 82 5.8 25 0.30 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

12 07.01.2016 41 81 4.5 20 0.21 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

13 13.01.2016 28 86 6.2 19 0.32 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

14 14.01.2016 24 78 4.8 27 0.24 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

15 20.01.2016 28 89 4.1 27 0.22 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

16 21.01.2016 27 78 4.8 29 0.26 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

17 27.01.2016 27 84 4.4 40 0.28 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

18 28.01.2016 39 82 4.9 31 0.28 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

19 03.02.2016 30 89 5.8 28 0.28 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

20 04.02.2016 20 70 4.5 31 0.35 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

21 10.02.2016 36 72 6.2 41 0.28 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

22 11.02.2016 38 74 4.8 23 0.28 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

23 17.02.2016 38 56 4.9 39 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

24 18.02.2016 25 65 4.8 25 0.22 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

25 24.02.2016 34 69 4.4 42 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

26 25.02.2016 32 69 4.1 42 0.20 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Maximum 43 89 6.2 42 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Minimum 20 41 4.1 18 0.20 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Average 30.7 72.8 5.0 29.3 0.28 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

98 %tile 42 89 6.2 42 0.37 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0



(BTAD), Assam


Table 3.18 : Ambient Air Quality (AAQ6)

S.

No.


µg/m3 µg/m

3 µg/m

3 µg/m

3 mg/m

3 µg/m

3 µg/m

3 µg/m

3 µg/m

3 ng/m

3 ng/m

3 ng/m

3

1 04.12.2015 31 49 8.0 34 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

2 05.12.2015 36 53 8.0 30 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

3 09.12.2015 38 52 7.0 35 0.49 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

4 10.12.2015 28 41 5.0 29 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

5 16.12.2015 27 39 6.0 28 0.50 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

6 17.12.2015 32 47 8.0 33 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

7 23.12.2015 30 45 6.0 43 0.31 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

8 24.12.2015 34 49 4.2 32 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

9 30.12.2016 24 43 6.0 35 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

10 31.12.2016 35 57 8.0 40 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

11 06.01.2016 32 54 4.3 27 0.43 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

12 07.01.2016 36 52 6.0 28 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

13 13.01.2016 43 65 7.0 30 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

14 14.01.2016 38 82 8.0 27 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

15 20.01.2016 35 41 4.2 26 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

16 21.01.2016 41 59 5.0 37 0.52 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

17 27.01.2016 38 61 8.0 36 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

18 28.01.2016 40 64 8.0 31 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

19 03.02.2016 34 73 4.5 38 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

20 04.02.2016 36 65 7.0 39 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

21 10.02.2016 41 70 5.0 28 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

22 11.02.2016 38 55 6.0 22 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

23 17.02.2016 30 58 6.0 31 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

24 18.02.2016 32 41 4.5 38 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

25 24.02.2016 34 45 8.0 36 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

26 25.02.2016 35 48 6.0 25 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Maximum 43 82 8 43 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Minimum 24 39 4.2 22 0.31 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Average 34.46 54.61 6.3 32.2 0.4 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

98 %tile 42 77.5 8 41.5 0.54 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0



(BTAD), Assam



S.

No.

Date PM2.5

µg/m3

PM10

µg/m3

SO2

µg/m3

NO2

µg/m3

CO

mg/m3

NH3

µg/m3

O3

µg/m3

Pb

µg/m3

C6H6

µg/m3

BaP (C20H12)

ng/m3

As

ng/m3

Ni

ng/m3

1 04.12.2015 42 82 8.0 35 0.44 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

2 05.12.2015 40 88 8.0 30 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

3 09.12.2015 42 89 7.0 35 0.49 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

4 10.12.2015 38 83 5.0 29 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

5 16.12.2015 35 75 6.0 28 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

6 17.12.2015 34 89 8.0 33 0.38 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

7 23.12.2015 31 88 6.0 43 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

8 24.12.2015 36 89 4.2 32 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

9 30.12.2016 34 81 6.0 35 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

10 31.12.2016 31 75 8.0 40 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

11 06.01.2016 33 67 4.3 27 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

12 07.01.2016 40 66 6.0 28 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

13 13.01.2016 43 85 7.0 32 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

14 14.01.2016 39 55 5.5 29 0.50 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

15 20.01.2016 30 60 4.5 28 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

16 21.01.2016 42 83 5.0 37 0.52 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

17 27.01.2016 42 75 8.0 36 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

18 28.01.2016 23 85 8.0 37 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

19 03.02.2016 39 68 4.5 38 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

20 04.02.2016 35 74 7.0 39 0.32 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

21 10.02.2016 40 78 5.0 28 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

22 11.02.2016 36 76 6.0 22 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

23 17.02.2016 38 72 6.0 31 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

24 18.02.2016 32 64 4.5 38 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

25 24.02.2016 31 84 8.0 36 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

26 25.02.2016 39 70 6.0 25 0.49 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Maximum 43 89 8 43 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Minimum 23 55 4.2 22 0.32 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Average 36.3 77.0 6.2 32.7 0.4 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

98 %tile 42.5 89 8 41.5 0.54 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0



(BTAD), Assam



S.

No.

Date PM2.5

µg/m3

PM10

µg/m3

SO2

µg/m3

NO2

µg/m3

CO

mg/m3

NH3

µg/m3

O3

µg/m3

Pb

µg/m3

C6H6

µg/m3

BaP (C20H12)

ng/m3

As

ng/m3

Ni

ng/m3

1 04.12.2015 42 82 8.0 35 0.44 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

2 05.12.2015 40 88 8.0 30 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

3 09.12.2015 42 89 7.0 35 0.49 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

4 10.12.2015 38 83 5.5 29 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

5 16.12.2015 42 75 6.0 28 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

6 17.12.2015 44 60 8.0 32 0.35 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

7 23.12.2015 31 88 6.0 43 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

8 24.12.2015 36 89 4.2 32 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

9 30.12.2016 34 81 6.0 35 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

10 31.12.2016 31 75 8.0 40 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

11 06.01.2016 33 67 4.3 27 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

12 07.01.2016 40 66 6.0 28 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

13 13.01.2016 43 85 7.0 32 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

14 14.01.2016 38 83 8.0 23 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

15 20.01.2016 41 68 4.2 26 0.47 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

16 21.01.2016 42 83 5.0 37 0.52 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

17 27.01.2016 42 75 8.0 36 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

18 28.01.2016 23 85 6.0 37 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

19 03.02.2016 39 68 4.5 38 0.42 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

20 04.02.2016 35 74 7.0 39 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

21 10.02.2016 40 78 5.0 29 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

22 11.02.2016 36 76 6.0 22 0.39 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

23 17.02.2016 38 72 6.0 31 0.46 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

24 18.02.2016 32 64 4.5 38 0.41 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

25 24.02.2016 33 65 4.5 40 0.48 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

26 25.02.2016 40 70 6.5 34 0.51 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Maximum 44 89 8 43 0.56 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Minimum 23 60 4.2 22 0.33 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

Average 37.5 76.5 6.1 32.9 0.4 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0

98 %tile 43.5 89 8 41.5 0.54 <5.0 <5.0 <0.1 <0.1 <0.01 <1.0 <1.0






3.7.8 Stack Emissions Monitoring From DG Set Stack Table 3.20: Stack Emission Monitoring for DG Sets

Sn. Parameters DG Set Stack

( kVA)

DG Set Stack

( kVA)

1. Flue Diameter (mm) 150 150

2. Flue Gas:

• Temperature (oC) 286 272

• Velocity (m/s) 22.3 16.1

• Volume Flow Rate (Nm3/h) 756 560

3. Concentration of Pollutants

(mg/Nm3)

• SPM 32.7 33.9

• SO2 296.2 252.6

• NOx 331.7 281.3

3.8 Ambient Noise Levels

3.8.1 Introduction

Noise can be defined as an unwanted sound. It interferes with speech and hearing and is

intense enough to damage hearing or is otherwise annoying. The definition of noise as

unwanted sound implies that it has an adverse effect on human beings and their

environment. Noise can also disturb wildlife and ecological system.

3.8.2 Methodology

To understand the noise environment in the study area, a noise survey was conducted using

Sound Level Meter 2031 manufactured by Cygnet Systems. Noise measurements were

carried out at the same location where ambient air quality was monitored. The 24-hourly

sound levels were measured at each location once during the study period.






Figure 3.6: Noise sampling locations

3.8.3 Equivalent Sound Pressure Level (Leq)

The Leq is the equivalent continuous sound level, which is equivalent to the same sound

energy as the actual fluctuating sound measured in the same period. This is necessary

because sound from noise source often fluctuates widely during a given period of time. This

is calculated from the following equation:

L eq(hrly) = L50+ (L10 - L90)2/60

Also:

• Lday is defined as the equivalent noise level measured over a period of time

during day (6 AM to 10 PM).

• Lnight is defined as the equivalent noise level measured over a period of time

during night (10 PM to 6 AM).






Hourly measurements have been carried out in day and night time at Premises of IOCL,

Sukinapara, Baikhungaon, Madarpur, Namalpur, Dabli, Barshangaon,and Chitkagaon

locations during study period. Ambient Noise Levels monitoring locations are given in Figure

3.12.

Day and night-time Leq have been calculated from hourly Leq values and compared with the

stipulated standards as given in Table 3.21.

Table 3.21: Ambient Standards in Respect of Noise

Area Code Category of Area Leq. Limits in dB(A)

Day Time Night Time

A Industrial Area 75 70

B Commercial Area 65 55

C Residential Area 55 45

D Silence Zone 50 40 Note: 1. Day-time is reckoned in between 6:00 a.m and 10:00 p.m.

2. Night time is reckoned is between 10:00 p.m and 6.00 a.m.

3. Silence Zone is defined as areas upto 100 m around such premises as hospitals,

educational, institutions and Courts. The Silence Zones are to be declared by the competent

authority.

Table 3.22 gives the day and night-time Leq noise levels. Measured Leq noise levels are

below the prescribed limit stipulated for commercial area at Premises of IOCL, Sukinapara,

Baikhungaon, Madarpur, Namalpur, Dabli, Barshangaon, and Chitkagaon.

Table 3.22 - Day and Night Time Leq in the Area

Locations Category of Area Day Time

dB(A)

Night Time

dB(A)

Project site Industrial 55.3 50.3

Sukinapara Residential 54.3 48.2

Baikhungaon Residential 53.4 47.9

Madarpur Residential 57.3 44.9

Namalpur Residential 45.6 40.65

Dabli Residential 55.9 39.48

Barshangaon Residential 54.0 45.9

Chitkagaon Residential 44.6 42.8

Graphical presentation of day and night time noise levels in the study area is shown in

Figure.






Figure 3.7: Graphical Presentation of Day & Night Time Noise Levels

3.9 Land Use Pattern

LAND ENVIRONMENT

The proposed DHDT and Reformer Revamp projects may affect the existing land use pattern

in the study area by change in present landuse and encouraging more entrepreneurs to go

in for the new industries in this region. This in turn may have further impact on the existing

basic infrastructure. Therefore the land environment background status in terms of the land

use pattern needs to be assessed. The land use pattern study has been carried out by M/s

SGS India Limited, Kolkatta.

In order to characterize the soil quality within the study area, soil samples have been

collected from nine different locations in the study area.

In view of the above, it is very important to collect the information on land, water and

vegetation sources such as their pattern of utilization, spatial distribution and aerial extent.

Besides, it is equally important also to establish the representative baseline characteristics

of the soil in the surrounding area.

The following subsections describe the land use pattern within 10-km radius.

LAND USE PATTERN

Land use/Land cover studies form an important input for any Environmental Impact Analysis

study. The establishment of any human activity, in many cases, has an effect on the

surrounding land cover. In view of this, land use/land cover assessment study using remote

sensing techniques has been attempted. The study involves the 10-km region around the

existing refinery with the details of built-up land, forest cover, agricultural land, wastelands,

water bodies, major road/rail etc. The plant site is located in Dhaligaon, Assam State. The






mapping of land use/land cover is done on a scale of 1:50,000 with detailed statistics

furnished for the study area.

LAND USE/LAND COVER CLASSIFICATION SYSTEM

Land use refers to, `man's activities and the 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 transformations. The term’s land use and land cover being closely

related are inter-changeable, because the former is generally inferred based on the cover

and on the contextual evidence.

The purpose of a land use/land cover classification system is to enable to arrange/group the

array of information available under a suitable framework to facilitate systematic inventory

and mapping besides incorporating land use details obtained from satellite and other

sources. The present framework of land use/land cover classification developed is amenable

to remotely sensed satellite data on 1:50,000 scale. The land use/land cover classification is

given in Table 4.13. It meets the basic information needs of the study.






METHODOLOGIES AND APPROACH

Precision geocoded IRS –P6 (LISS-III) false color composite (FCC) data acquired on 1 March

2006 on 1:50000 scale for the segment of Lat 26o25’ – 26o40’ and Long 90o23’ – 90o38’ were

procured from NRSA, Hyderabad and used. The geocoded false colour composite is

presented in Figure. 4.3

Interpretation of image was carried out in two stages for extracting information on various

land use / land cover units by analyzing imagery in consultation with topographical map.

Monoscopic visual interpretation technique based on image characteristics /elements i.e.

color, tone, texture, pattern, size, shape, association, etc. enabled to identify and delineate

different land use/land cover units and accordingly image interpretation key was developed.

Analysis of images was carried out in succession using the interpretation key/ legend. Image

analysis carried out thoroughly examined and adjusted in the light of ground information

collected and image – ground feature relationship was established. The delineation of each

unit was finalized successively. Necessary correlation was made with regard to identification

and delineation of mapping units and Land use/ Land cover maps were finalized. The extent

of individual mapping unit was measured plannimetrically after taking out a print of

individual sheet.

The data was analyzed and segregated into 12 distinct categories under 5 groups of Plain,

Open Scrub, Hill, Habitation and Water bodies, Refer the table below:

S.No: Level - I Level-II

1 Built up Land 1.1 Habitation/ Settlement 1.2 Industrial Area 1.3 Railway Station

2 Agricultural Land 2.1 Crop Land (With & Without crop)

2.2 Agricultural Plantation (Tea gardens &

others)

3 Forests 3.1 Moderately Dense Sal Forests 3.2 Scrub Forest

4 Wastelands 4.1 Water logged /Marshy (seasonal)

5 Water bodies 5.1 Rivers/Streams

6 Others 6.1 Settlement with mixed vegetation 6.2 Grass/Grazing Lands 6.3 River sand

OBSERVATIONS AND ASSESSMENT OF LAND USE/COVER IN STUDY AREA

Bongaigaon Refinery & Petrochemicals Ltd., which manufactures various petrochemical

products, is located adjacent to highway 31C, just 2 kms from New Bongaigaon. The study

area of 10 Kms around the site covers the area between New Bongaigaon, Bongaigaon and

Aie River. The railway line of North Eastern Frontier passes from Bongaigaon and a coach






repairing industry belonging to Indian Railways is located at Bongaigaon. The existing land

use pattern observed is predominantly agricultural which is seen in the plains and mixed

vegetation which is associated with the settlements.

The areas of various land use/land cover classes are given in Table 4.14. The detailed

description and explanation of different land use/land cover categories observed in the

study area is discussed below.

(A) Built-Up Land

It is defined as an area of human habitation developed due to intensive non-agricultural use.

The major categories discernable with satellite data in the study area include Built Up

(Mixed Residential) and Industrial.

The Dense Residential comprises the New Bongaigaon & Bongaigaon built up areas which

reflect sky blue in satellite data and is devoid of good vegetation.

In addition, transportation network is also clearly seen on the image. Mixed Built Up land is

intermixed with good vegetative cover and the reluctance on the image along the

transportation network and adjoining land is reddish brown in colour. Several small

settlements are scattered throughout the transportation lines of National Highways in the

study area. These settlements are found to be situated close to the valleys and along the

road network.

Most of the settlements are intermixed and the settlements are encirlced with plantation

like coconut, areca nut and banana. In addition, several dwellings are having small open

lands in front of houses which could not be represented due to scale limitations. Some of

the Major settlements identified in the study area are, Dhaligaon; Chapaguri; Raumari;

Sukharpara; Popragaon; Paschim Daisumghuri; Nilibari; Bhirangaon; Bongaigaon; New

Bongaigaon; Mulgaon; Dakhlapara; Bakhrapara; Chaprkhata; Sidli; Damgaon; Pakriguri;

Kasikatra; Amguri; Kokragaon; Dakshin Kajalgaon; Ulubari; etc. Because of canopy cover, the

category of built up land is placed under mixed category.

The industrial area is seen in the central portion of the radius i.e., are being covered by BGR

and New Bongaigaon Railway yard.

(B) Agricultural Land

Agricultrual land use by and large is dependent on agro –climatic conditions prevalent in the

area. The present land use/land cover apppears to have well adopted itself to the

topography, soil and rainfall pattern, besides the natural vegetation and the land use

practices of the people in the area. Agricultural land in the study area is confined to the

plain areas. The agricultrual lands in the present study are classified as:

1) Cultivated land






2) Agricultural plantations (Tea Gardens & Others)

(i) Cultivated land

The area represents diversities in the agricultural practices due to location and

physiography. The area receives moderate rainfall and permit growing of Sali paddy, which

is confined to the plain valley portions. Sali Paddy and Jute are the main crops and other

crops grown are pulses, Mustard, early Ahu, Wheat, Boro paddy, Potato and Vegetables.

The total area occupied under cultivated land is 171.37 sq.km (56.35% of Total Study area).

(ii) Agricultural Plantations

This class of land use includes plantation area under Birijhora Tea Gardens located near

Bongaigaon and adjacent to Bhageswari temple area. This land use category of the study

area is representing 8.80 sq km (2.89%) of the total study area. Most of the plantations are

seen close to the valleys and are thickly covered with mixed vegetation.

(C) FORESTS

It is an area (within the notified forest boundary) bearing an association predominantly of

trees and other vegetation types capable of producing timber and other forest produce. If

density of vegetation in terms of Crown cover is more than 40% it is termed as dense or

closed forest. If it falls less than 20% it is termed as degraded forest. Forests exert influence

on climate and water regime and also provide shelter for wildlife and livestock. The area

under Moderately Dense Sal Forests account for 8.43 % of the Total Study Area.

(D) WASTELANDS

Wasteland is described as “degraded land” which can be brought under vegetative cover

with reasonable effort and which is currently under-utilised for lack of appropriate water

and land management or an account of natural causes (NRSA 1991). Wastelands account for

18.46 sq km (6.07%) of the study area. Only two types of wasteland categories are seen in

the study area viz (i) Waterlogged / marshy lands and (ii) Land with or without Scrub.

(i) WATER LOGGED / MARSHY (SEASONAL)

Surface water logged land is seen along the courses of streams/ rivers in the study area. The

water is seen near the surface and is covered by different types of aquatic species. The

water logged area is observed in the interfluves. In the study area, the Waterlogged areas

are saturated with water by Surface congestion, due to flooding or high ground water table

through the depth of root zone for periods long enough to limit, the growth of crops. These

are distinctly seen as light to dark blue in tone with varying size. Some of the notable

waterlogged areas are Nayachara Bil; Bhasamari Bil; areas nearer to Krishnapur,

Mangalagaon etc. In the study area these are noticed in the flood plains along the stream

channels which are composed of low lands and depressions. The area is subjected to

recurring annual water logging during the monsoon season. In addition it has a direct

bearing with the Aie river, since most of the waterlogged or Bil areas are lying adjacent to

this river. Area account for this category is 22.01 sq.km (7.23%).






(ii) LAND WITH OR WITHOUT SCRUB

This category of land use is seen on the uplands which are flat topped and is seen scattered

adjacent to settlements with mixed vegetation in the study area. In addition to this, small

isolated scrubs, were also noticed during ground truth. The soils are acidic, poor in mineral

nutrients and have a low silica / sesquioxide ratio. The pronounced physical and chemical

properties exercise a marked influence on vegetatiton. The influence of soil conditions have

a direct bearing on the growth and distribution of vegetation in the area. These scrub lands

are resulting as a process from long fallows in adjacent portions of major settlements. Area

calculated for this category is 0.78 sq.km (0.25%).

(E) WATER BODIES

River / Streams, Tanks /pond are the important water bodies indentified in the study area.

Major rivers which cut across the study area are Aie River, Tangainadi; Ghorabandha Nadi;

Ekanjani Nadi etc. Aie River which flows in North East directions of study area is Major River

which is very dynamic and is slowly migrating its course from original inception when

observed the satellite imagery (Presence of Palaeo Channels and cut off meanders neary by

Aie River). Water spread area is changing the adjacent cropland/ Scrub land/ river sand scenario. Area

calculated for this category is 8.68 sq.km (2.85%).

(F) OTHERS

This category includes all those which can be treated as miscellaneous because of their

nature of occurrence, physical appearance and other characteristics. In the present study

categories identified under this includes Grass lands.

Grass lands

It is an area of land covered with natural grass alongwith other vegetation, often grown for

fodder to feed cattle and other animals. Such lands are found in river beds, on uplands or

hill slopes. Here grasslands are occuring adjacent to Aie River on river sand beds confining to

areas Paschim Davisamguri. Temporary shift in grass land occurrence is seen due to change

in river course. The height of grass is decreasing as not much importance is being given for

retention of these areas. Area estimated under this category is 4.92 sq. km (1.61).

Table 4. 14 Land Use/Land Cover Area Statistics in Area of 10 Km Radius around BGR

Sl. No. LANDUSE Area in Ha. (%)

1 Built up Area (Residential) 550 1.8

2 Industrial area 137 0.51

3 Railway Station 10 0.03

4 Crop Land (With & Without Crop) 17137 56.35

5 Agricultural Plantation (Tea garden & Others) 880 2.89

6 Scrub Forests 78 0.25






7 Moderately Dense Sal Forest 2564 8.43

8

Water Logged/Water body/Marshy

(Seasonal) 2201 7.23

9 River/Stream 868 2.85

10 Settlement with mixed vegetation 4567 15.01

11 Grass/Grazing Land 492 1.61

12 River Sand 927 3.04

Total 30411 100

3.10 Biological Environment

Change in the surrounding environment could cause loss of species or decrease in

biodiversity of the area. Therefore, the present study is proposed to assess the impact of

proposed project on biological environment. Accordingly, mitigation measures are evolved

to sustain the biological diversity. In general Biological diversity is represented by flora and

fauna. For the study of biological environment of any area Flora is categorized mainly in to

three groups as herbs, shrubs and trees; similarly fauna is divided into mammals, birds and

reptiles.

3.10.1 Introduction

The term biological environment covers the prevalence of all living forms plants and animals

both terrestrial and aquatic in nearby area. Living forms cover a very wide spectrum of

species and even a small area may have thousands of species if all bacteria, protozoa,

worms, insects, plants, animals and birds are to be included. In the present study, higher

taxa (trees, small trees, shrubs, under shrubs, climbers and grasses) and fauna (mammals,

birds and reptiles) are covered for impact assessment purpose. It is needless to emphasize

that living system is extremely complicated. They are directly affected by changes in the

physical environment but may often either adapt or avoid the adverse environment.

3.10.2 Flora Found in the study area

Tree, shrubs, herbs and grass species observed within 10 km radius area of IOCL plant are

given in Table 3.24.

Table 3.24: List of Trees, Shrubs, and Climbers found in the Study Area

Sn Vernacular Name Botanical Name

A Tree

1. Bunya Pine Araucaria Bidwillii Hook.

2. Hoop Pine Araucaria Cunninghamii

3. Toddy Palm Borassus Flabellifar

4. Beach Oak Cassuarina Equisetifolia

5. Earleaf Accacia Acacia Auriculiformis

6. Kadamba Anthocephalus Cadamba Miq.

7. Bael Aegle Marmelos







8. Shirish Albizzia Lebbeck

9. Saptaparni Alstonia Shcolaris

10. Captains cook’s pine Araucaria Cookii

11. Betel Palm Areca Catechu

12. Jackfriut Artocarpus Heterophyllus

13. Neem Azadirachta Indica

14. White orchid tree Bauhinia Accuminata

15. Peacock flower Caesalpinia Pulcherrima

16. Lemon bottle brush Callistemon Citrinus

17. Pappaya Carica Papaya

18. Amaltas Cassia Fistula

19. Indian bay leaf Cinnamomum Tamala

20. Coconut tree Cocos Nucifera L.

21. Croton Codiaeum Variegatum

22. Sheesham Dalbergia Sisso Roxb.

23. Gulmohar Delonix Regia

24. Water Hyacinth Eichhornia Crassipes

25. Amla Embelica Officinalis

26. Blue gum Eucalyptus Globosus

27. Eucalyptus Eucalyptus Hybrid

28. Banyan Tree Ficus Benghalensis

29. Peepal tree Ficus Religiosa

30. Silky oak Grevellia Robusta

31. Shoe flower Hibiscus Rosa Sinensis

B Shrubs

1. Kapuri jadi Aerva Sanguinolenta

2. American aloe Agave Americana

3. Aloe vera Aloe Barbedensis

4. Prickly poppy Argemone Maxicana

5. Bougainvillea Bougainvillea Spectabilis

6. Kardal Canna Indica

7. Hemp Cannabis Sativa

8. Periwinkle Catharanthus Roseus

9. Datura Datura Metel

10. Female dragon Dracaena Sp

11. Golden dew drop Duranta Repens

12. Torch tree Ixora Arborea

13. Jungle geramium Ixora Coccinea

14. Baner Senna Sophera

15. Sickle senna Senna Tora

C Climber

1. Malabar spinach Basella Alba







2. Balloon vine Cardiopermum Halicacabum

3. Asian pigeonwings Clitoria Ternatea

4. Tendli Coccinia Grandis

5. Amar bel Cuscuta Reflexa

6. Purple yam Dioscorea Alata

7. Calihari Gloriosa Superba

8. Water spinach Ipomoea Aquatica

9. Mile a minute vine Ipomoea Cairica

10. Cypress vine Ipomoea Quamoclit

D Herbs, Orchids etc.

1. Kudaliya Desmodium trifolrum

2. Crab’s eye Abrus precatorius

3. Indian mallow Abutilon indicum

4. Indian nettle Acalypha indica

5. Devil’s horsewhip Achyranthes aspera

6. Maidenhair fern Adiantum caudatum

7. Hamsapadi Adiantum philippense

8. Cat’s tail orchid Aerides odorata

9. Goat weed Ageratum conyzoides

10. Elephant ear Alocasia cucullata

11. Alligator weed Alternanthera philoxeroides

12. Joy weed Alternanthera sessilis

13. Spiny amaranth Amaranthus spinosus

14. Horseradish Amaranthus variegata

15. Pigweed Amaranthus viridis

16. Elephant foot yam Amorphophallus campanulatus

17. Beard grass Andropogon ascendis

18. Gaint fern Angiopteris evecta

19. Prickly poppy Argemone maxicana

20. Birdnest fern Asplenium nidus

21. Water velvet Azolla pinnata

22. Bamboo Bambusa sp.

23. Alugbati Basella alba

24. Punarnava Boerhavia diffusa

25. Alena Boerhavia repens

26. Madanghanti Borreria articularis

27. Cathedral bells Bryophyllum pinnatum

28. Carey’s bulbophyllum Bulbophyllum careyanum

29. Splitawn sedge Carex spp.

30. Common cockscomb Celosia cristata

31. Gotu kola Centella asiatica

32. Goosefoot Chenopodium album







33. Love grass Chrysopogon aciculatus

34. Cat whiskers Cleome gynandra

35. Purple cleome Cleome rutidosperma

36. Tickweed Cleome viscosa

37. Taro Colocasia esculenta

38. Bengal dayflower Commelina benghalensis

39. Gaint dodder Cuscuta reflexa Roxb.

40. Fern Cyclosorus extensus

41. Sonu Cymbidium aloifolium

42. Bermuda grass Cynodon dactylon

43. Mullumbimby couch Cyperus brevifolius

44. Poorland flatsedge Cyperus compressus

45. Piedmont flatsedge Cyperus distans

46. Ricefeild flatsegde Cyperus iria

47. The Noble Dendrobium Dendrobium nobile

3.10.3 Wildlife in the Study Area

The information of important terrestrial animal groups such as birds, reptiles and mammals

were collected by trekking inhabiting area, along the road, nearby forest areas and

agricultural fields present in the impact zone. An inventory of the animals has been

prepared separately for mammals, reptiles and birds.

Mammals

Sn. Vernacular name Scientific name

1. Hog Deer Axis Porcinus

2. Wild Boar Sus Scrofa

3. Leopard Cat Prionailurus Bengalensis

4. Jungle Cat Felis Chaus

5. Asiatic Jackal Canis Aureus

6. Bengal Fox Vulpes Bengalensis

7. Small Indian Civet Viverricula Indica

8. Common Palm Civet Paradoxurus Hermaphroditus

9. Indian Grey Mangoose Herpestes Edwardsii

10. Small Asian Mangoose Herpestes Javanicus

11. Western Hoolock Gibbon Hoolock Hoolock

12. Rhesus Macaque Macaca Mulatto

13. Assam Macaque Macaca Assamensis

14. Capped Langur Trachypithecus Pileatus

15. Bengal Slow Loris Nycticebus Bengalensis

16. Chinese Pangolian Manis Pentadactyla

17. Indian Palm Squirrel Funambulus Palmarum






18. Porcupine Hystrix Brachyura

19. Lesser Bandicoot Rat Bandicota Bengalensis

20. Hoary Bamboo Rat Rhizomys Pruinosus

21. Indian Flying Fox Pteropus Giganteus

22. Short Nosed Indian Fruit Bat Cynopterus Sphinx

23. Least Horseshoe Bat Rhinolophus Pusiilus

24. Lesser Asiatic Yellow Bat Scotophilus Kuhlii

25. Asian House Shrew Suncus Murinus

26. Mole Shrew Anourosorex Squamipes

27. Gangetic Dolphin Platanista Gangetica

Reptiles


1. Tree Frog Polypedates Leucomystax

2. Ornamented Pygmy Frog Microhyla Ornate

3. Indian Bull Frog Hoplobatrachus Tigerinus

4. Common Pond Frog Fejervarya Limnocharis

5. Assam Hills Frog Clinotarsus Alticola

6. Asiatic Hills Frog Hylarana Garoensis

7. Water Frog Python Python Molurus

8. Asiatic Rock Python Ptyas Mucosus

9. Common Rat Snake Oligodon Cyclurus

10. North Eastern Kukri Snake Coelognathus Radiatus

11. Rat Snake Chrysopelea Ornata

12. Golden Tree Snake Bungurus Fasciatus

13. Banded Krait Hemidactylus Frenatus

14. House Gecko Calotes Versicolor

15. Indian Garden Lizard Pangshura Tecta

16. Indian Roofed Turtle Cuora Amboinensis

17. South Asian Box Turtle Nilssonia Gangetica

18. Peacock Soft Shell Turlte Nilssonia Hurum

19. Indian Fpal Shell Turlte Lissemys Punctata

Bird species


1. Little Grebe Tachybaptus Ruficollis

2. Great Crested Grebe Podiceps Cristatus

3. Great Cormorant Phalacrocorcix Carbo

4. Little Cormorant Phcdacrocorax Niger

5. Oriental Darter Anhinga Melanogaster

6. Grey Heron Ardea Cinerea

7. Cattle Egret Bubulcus Ibis






8. Great Egret Casmerodius Dibits

9. Purple Heron Ardea Purpurea

10. Indian Pond Heron Ardeola Grayii

11. Intermediate Egret Ardea Intermedia

12. Little Egret Egretta Garzetta

13. Cinnamon Bittern Ixubrychus Cinnamomeus

14. Great Bittern Botaurus Stellaris

15. Black Crown Night Heron Nycticorax Nycticorax

16. Asian Open Bill Anastonnis Oscitans

17. Lesser Adjustant Stork Leptoptilos Javanicus

18. Lesser Whistluing Duck Endrpcygna Javanica

19. Fulvous Whistling Duck Dendrocygna Bicolor

20. Ruddy Shelduck Tadorna Ferruginea

21. Pintail Anas Acuta

22. Common Teal Anas Crecca

23. Bar Headed Goose Anser Indicus

24. Cotton Pygmy Goose Nettapus Coromandelianus

25. Tufted Duck Aythya Fuligula

26. Swamp Francolin Francolinus Gulans

27. Kalij Pheasant Lophura Leucomelanos

28. Black Francolin Francolinus Francolinus

29. Red Jungle Fowl Gallus Gallus

30. Water Cock Gallicrex Cinerea

3.10.4 Environmental Sensitive Area

The terrestrial wildlife habitats within the study area are represented by Kakoijana, Nakatti

and Bhumeshwar Reserved Forests of the Aie Valley Forest Division. The details of the

Reserved Forest patches which fall within the study area are provided in Table

Reserved Forest Areas Represented in the Study Zone

Sl. Reserved Forests Total Area of Area within the % Area within

No. RF (km2) Study Zone (km

2) the Study Zone

1 Bhumeshwar

Reserved Forest

(proposed )

14.16 4.0 28.4%

2 Nakatti Reserved

Forest 28.79 3.37 11.71%

3 Kakoijana Reserved

Forest 17.24 0.52 0.03%






All the Reserved Forests listed above are a part of the sub – montane tract known as the

Bhabhar area. The soil over most of this area is dry sandy loam superimposed on beds of

pebbles with very thin layer of humus.

Of the various wetlands located within the study area, Nayachara Lake commands greater

importance as a wetland habitat. This beel with an area of 0.30 km2 located approximately 7

km from the BGR Township has been identified as an important wintering ground for large

number of wetland bird species. Its conservation significance as a habitat of resident bird

species such as Lesser adjutant stork which is listed in Schedule I of the Wildlife Protection

Act (1972) is being increasingly recognized by the local conservation groups. This beel has

been included as a site for Asian Wetland Waterfowl count from this year onwards. The

local nature conservation groups are already making efforts to revive this wetland through

environmental awareness campaign and through their efforts of developing wetland revival

and species conservation plans in consultation with officials of the State Forest Department

3.11 Socio-Economic Environment

Socio-economic environment in the vicinity of any ensuing project is affected by the mode

of change that is likely to occur due to the beneficial or adverse effects arising out of the

project activity. The impact of such change is dependent upon likely job opportunities

economic output immigration strain on the existing basic amenities and overall impact on

the quality of environment, which may impair the health status of the people living in that

geographical area.

The projection of such assessment calls for collection of the baseline and background

information about the socio-economic and demographic environment of the surrounding

areas of the proposed site. A study area comprising an area of 10 km radius around the

proposed project was chosen for studying the socio-economic characteristics:

The proposed project comes under Chirang district, which is situtated in the western part of

Assam and bounded by the districts of Kakrajhar, Goalpara, Barpetta, and foot hills of

Bhutan. The economy of the study area is primarily agrarain. The agro-climatic conditions of

the region are favorable for the development of various agriculture and allied activities. The

infrastructural facilities available in the region also offer scope for a number of non-farm

sector activities. Agriculture is the most important economic activity in the district. Animal

husbandry and fisheries are the other important allied activities.

Bongaigaon district is bounded by Barpeta district in the east Dhubri and Kokrajhar district

towards the west, Goalpara district in the south and Chirang district in the north. The

Headquarters of the district is located at Bongaigaon town situated at the lower part of the

Brahmaputra Valley. In the district some jurisdictional changes has taken place during 2001-

2011. As per Notification No.GAG(B) 137/2002/Pt/117 dated 30th October,2003 , 353

villages of geographical area 676.80 Sq.Km. and Bijni(TC) of 3.00 Sq.Km was carved out from

the district for inclusion in the new district of Chirang. The total area of the district is 1093

square kms. The rank of this district in comparison to other districts of Assam in terms of

area is 25th. It is one of the smallest districts of Assam. Bongaigaon district possesses three






sub divisions namely Bongaigaon, North Salmara and Bijni Subdivisions. Bongaigaon

Subdivision consists of two Revenue Circles such as Sidli (part II) and Bongaigaon(Pt)

Revenue circles, North Salmara sub division has also two-revenue circles viz Boitamari and

Srijangram and Bijni Sub division occupies only Bijni(Pt) Revenue Circle. Thus the district has

all together 5 revenue circles with 563 villages. As per Census 2011, Bongaigaon district is

comprised of 5 towns (Two Statutory Towns and Three Census Towns) namely Bongaigaon

(MB) ,Abhayapuri (TC) , BRPL town ship (CT) , New Bongaigaon Rly Colony (CT) and

Chalantapara Pt-IV (CT).

In Bongaigaon district, Srijangram Revenue Circle is the most populous having 266700

persons while Sidli (Pt) is the least populous Revenue Circle having 58371 persons. Among

the CD Block, Boitamari CD Block has the highest number of population with 142684

whereas the lowest is found in Sidli-Chirang (Part) CD Block with 6001. In the district there

are 5 Revenue Circles and 6 CD Blocks which comprises 563 villages including 28 uninhabited

villages. The district comprises five (5) towns: 2 Statutory Towns and 3 Census Towns.

BOngaigaon (MB) is the most populous with 67322 persons while Chalantapara Pt IV (CT) is

the smallest in population with 5744 souls. While the highest number (142) inhabited

villages is found in Boitamari CD Block and lowest inhabited villages (83) is found in

Manikpur (Pt) CD Block. The largest village by population is Borpathar Part with 5458

persons under Dangtola CD Block and the smallest village is Mahadeb Hill with 1 person

under Boitamari CD Block.

Socio-economic profile of all these villages in terms of demographic characteristics like

population, literacy, occupational structure, and basic infrastructure was collected with the

help of Survey of India toposheets and 2011 census data

3.11.1 Social Profile of the Project District

The sex ratio is expressed as number of female per 1000 male. Sex ratio is an important

factor in demographic study. This is linked with women's development status and also

occupational status of an area. The total sex ratio of Bongaigaon is 966 females/ 1000 male.

Lower sex ratios in the urban areas are generally expected as many male migrate there for

employment. The sex ratio at Bongaigaon Railway Colony is lowest as it is mostly an area of

railway employees from different areas. It has been seen that sex ratio in Scheduled Castes

and Scheduled Tribes is generally high

Demographic and Occupational Pattern

As per the Census data 2011, the demographic profile of the district shows that 45.08 % of

the total rural population in the district belongs to the minority community of which

Muslims comprise 94%. The population density in the district with 420 persons per sq. km is

significantly higher than the state average which stands at 340 persons as per the 2011

census. With a total of 168556 households, the district comprises 145300 rural households

and 23256 urban households.

The decadal population variation in the district shows that there has been two decades

during which the population of the district increased at a high rate.






Place 1901-

1911

1911-

1921

1921-

1931

1931-

1341

1941-

1951

1951-

1961

1961-

1971

1971-

1981

1991-

2001

2001-

2011

Bongaigaon 29.94 26.94 15.94 14.97 9.31 60.81 40.29 64.64 12.05 20.59

Assam 16.99 20.48 19.91 20.40 19.93 34.98 34.95 53.26 18.92 17.07

Source: Statistical Handbook, Assam; 1996, 2006, Census Of India 2011, Assam.

Demographic details of Study Area for Bongaigaon is presented in Table below:

State District

Number of Villages Total 26,395 563

Inhabited 25,372 535

Uninhabited 1,023 28

Number of Towns Statutory 88 2

Census 126 3

Total 214 5

Number of Households Normal 6,387,047 149,620

Institutional 16,131 281

Houseless 3,293 117

Population Total Persons 31,205,576 738,804

Males 15,939,443 375,818

Females 15,266,133 362,986

Rural Persons 26,807,034 628,994

Males 13,678,989 319,786

Females 13,128,045 309,208

Urban Persons 4,398,542 109,810

Males 2,260,454 56,032

Females 2,138,088 53,778

Percentage Urban Population 14.1 14.86

Decadal Population Growth

2001-2011 Number Percentage Number Percentage

Persons 4,550,048 17.07 126,139 20.59

Males 2,162,406 15.70 60,281 19.10

Females 2,387,642 18.54 65,858 22.16

Area (in sq Km.) 78438 1093.00

Density of Population (Persons 398 676

per sq Km.)

Sex Ratio Total 958 966

(Number of females per 1000 males) Rural 960 967

Urban 946 960






State District

Number Percentage Number Percentage

Literates Persons 19,177,977 72.19 434,078 69.74

Males 10,568,639 77.85 237,114 74.87

Females 8,609,338 66.27 196,964 64.43

Scheduled Castes Persons 2,231,321 7.15 82,784 11.21

Males 1,145,314 7.19 42,513 11.31

Females 1,086,007 7.11 40,271 11.09

Scheduled Tribes Persons 3,884,371 12.45 18,835 2.55

Males 1,957,005 12.28 9,377 2.50

Females 1,927,366 12.63 9,458 2.61

Workers and Non-Workers

Total Workers (Main and Persons 11,969,690 38.36 255,806 34.62

Marginal) Males 8,541,560 53.59 197,542 52.56

Females 3,428,130 22.46 58,264 16.05

(i) Main Workers Persons 8,687,123 27.84 191,671 25.94

Males 7,034,642 44.13 167,483 44.56

Females 1,652,481 10.82 24,188 6.66

(ii) Marginal Workers Persons 3,282,567 10.52 64,135 8.68

Males 1,506,918 9.45 30,059 8.00

Females 1,775,649 11.63 34,076 9.39

Non-Workers Persons 19,235,886 61.64 482,998 65.38

Males 7,397,883 46.41 178,276 47.44

Females 11,838,003 77.54 304,722 83.95

Category of Workers (Main & Marginal)

(i) Cultivators Persons 4,061,627 33.93 83,442 32.62

Males 3,099,763 36.29 68,437 34.64

Females 961,864 28.06 15,005 25.75

(ii)Agricultural Labourers Persons 1,845,346 15.42 47,406 18.53

Males 1,129,210 13.22 30,088 15.23

Females 716,136 20.89 17,318 29.72

(iii)Workers in household Persons 491,321 4.1 9,485 3.71

industry Males 205,744 2.41 4,708 2.38

Females 285,577 8.33 4,777 8.20

(iv) Other Workers Persons 5,571,396 46.55 115,473 45.14

Males 4,106,843 48.08 94,309 47.74

Females 1,464,553 42.72 21,164 36.32






Table 3.25: Demographic and Occupational Details

Sl.

No. Description Total (nos.)

1. House Hold 1,50,018

2. Total Population 7,38,804

3. Total Male Population 3,75,818

4. Total Female Population 3,62,986

5. Total Population below 6 Yr 1,16,392

6. Male Population below 6 Yr 59,099

7. Female Population below 6 Yr 57,293

8. Schedule Caste Population 82,784

9. Schedule Caste Male Population 42,513

10. Schedule Caste Female Population 40,271

11. Schedule Tribe Population 18,835

12. Schedule Tribe Male Population 9,377

13. Schedule Tribe Female Population 9,458

14. Literate Population - Total 4,34,078

15. Literate Population – Male 2,37,144

16. Literate Population - Female 1,96,964

17. Total Worker Population 2,55,806

18. Total Worker Male 1,97,542

19. Total Worker Female 58,264

20. Main Worker Population 1,91,671

21. Main Worker Male 1,67,483

22. Main Worker Female 24,188

23. Cultivator –Total 66,767

24. Cultivator –Male 62,471

25. Cultivator –Female 4,296

26. Agricultural Labourer -Total 24,914

27. Agricultural Laborer-Male 19,359

28. Agricultural Laborer -Female 5,555

29. Household Worker –Total 4,756

30. Household Worker-Male 3,453

31. Household Worker -Female 1,303

32. Other Worker –Total 96,324

33. Other Worker-Male 82,000

34. Other Worker –Female 1,30,354

35. Marginal Worker –Total 64,135

36. Marginal Worker-Male 30,059

37. Marginal Worker –Female 34,076

38. Non Worker –Total 4,82,998

39. Non Worker-Male 1,78,276

40. Non Worker –Female 3,04,722

Source: Census Records 2011.






Religion wise data of Bongaigaon, 2011:

Description Total Percentage

Hindu 3,59,145 48.61 %

Muslim 3,71,033 50.22 %

Christian 5,924 0.80 %

Sikh 384 0.05 %

Buddhist 236 0.03 %

Jain 871 0.12 %

Others 9 0.00 %

Not Stated 1202 0.16 %

Source: http://www.census2011.co.in/

Location Total/

Number of

households Total population (including institutional

Population in the age-group 0-6 code District/ CD Block/ Rural/ with SC as and houseless population)

number Town Urban head Persons Males Females Persons Males Females

1 2 3 4 5 6 7 8 9 10

319 Bongaigaon - District Total 17,240 82,784 42,513 40,271 10,990 5,624 5,366

Rural 13,795 67,460 34,760 32,700 9,460 4,820 4,640

Urban 3,445 15,324 7,753 7,571 1,530 804 726

0173 Dangtol Total 2,275 10,269 5,147 5,122 1,226 605 621

Rural 1,753 7,923 3,977 3,946 1,012 505 507

Urban 522 2,346 1,170 1,176 214 100 114

0174 Boitamari Total 3,804 18,661 9,557 9,104 2,618 1,317 1,301

Rural 3,698 18,155 9,318 8,837 2,540 1,279 1,261

Urban 106 506 239 267 78 38 40

0175 Srijangram Total 2,286 11,082 5,762 5,320 1,561 805 756

Rural 2,286 11,082 5,762 5,320 1,561 805 756

Urban - - - - - - - 0176 Tapattary Total 2,744 13,834 7,193 6,641 1,980 1,036 944

Rural 2,744 13,834 7,193 6,641 1,980 1,036 944

Urban - - - - - - - 0177 Manikpur (Part) Total 3,314 16,466 8,510 7,956 2,367 1,195 1,172

Rural 3,314 16,466 8,510 7,956 2,367 1,195 1,172

Urban - - - - - - - 0178 Sidli-Chirang (Part) Total 81 303 148 155 15 5 10

Rural - - - - - - - Urban 81 303 148 155 15 5 10

URBAN

801620 Bongaigaon (MB) Urban 2,055 8,984 4,584 4,400 875 481 394

New Bongaigaon Rly.

301325 Col. (CT) Urban 522 2,346 1,170 1,176 214 100 114

Chalantapara Pt IV

301473 (CT) Urban 106 506 239 267 78 38 40

801621 Abhayapuri (TC) Urban 681 3,185 1,612 1,573 348 180 168

301806 B.R.P.L. Township (CT) Urban 81 303 148 155 15 5 10






District/ CD

Block/ Literates Illiterates Total workers

Total

Rural/

Town Persons Males Females Persons Males Females Persons Males Females Urban

2 11 12 13 14 15 16 17 18 19 3 Bongaigaon -

District 50,829 28,971 21,858 31,955 13,542 18,413 29,246 23,499 5,747 Total 39,273 22,713 16,560 28,187 12,047 16,140 23,954 19,134 4,820 Rural 11,556 6,258 5,298 3,768 1,495 2,273 5,292 4,365 927 Urban Dangtol 6,612 3,667 2,945 3,657 1,480 2,177 3,801 2,803 998 Total 4,827 2,699 2,128 3,096 1,278 1,818 3,036 2,190 846 Rural 1,785 968 817 561 202 359 765 613 152 Urban Boitamari 10,338 5,942 4,396 8,323 3,615 4,708 6,461 5,195 1,266 Total 10,034 5,785 4,249 8,121 3,533 4,588 6,300 5,062 1,238 Rural 304 157 147 202 82 120 161 133 28 Urban Srijangram 6,732 3,906 2,826 4,350 1,856 2,494 4,379 3,211 1,168 Total 6,732 3,906 2,826 4,350 1,856 2,494 4,379 3,211 1,168 Rural - - - - - - - - - Urban Tapattary 8,173 4,783 3,390 5,661 2,410 3,251 4,772 4,044 728 Total 8,173 4,783 3,390 5,661 2,410 3,251 4,772 4,044 728 Rural - - - - - - - - - Urban

Manikpur

(Part) 9,507 5,540 3,967 6,959 2,970 3,989 5,467 4,627 840 Total 9,507 5,540 3,967 6,959 2,970 3,989 5,467 4,627 840 Rural - - - - - - - - - Urban

Sidli-Chirang

(Part) 284 142 142 19 6 13 94 81 13 Total - - - - - - - - - Rural 284 142 142 19 6 13 94 81 13 Urban URBAN

Bongaigaon

(MB) 6,740 3,671 3,069 2,244 913 1,331 3,253 2,650 603 Urban

New

Bongaigaon

Rly.

Col. (CT) 1,785 968 817 561 202 359 765 613 152 Urban

Chalantapara

Pt IV

(CT) 304 157 147 202 82 120 161 133 28 Urban

Abhayapuri

(TC) 2,443 1,320 1,123 742 292 450 1,019 888 131 Urban

B.R.P.L.

Township

(CT) 284 142 142 19 6 13 94 81 13 Urban






INDUSTRIAL CATEGORY

Location

code

District/ CD

Block/

Total/

Rural/ Main workers Cultivators Agricultural labourers

number Town Urban

Person

s Males Females Persons Males Females Persons Males Females

1 2 3 20 21 22 23 24 25 26 27 28

319 Bongaigaon -

District Total 22,774 20,295 2,479 5,686 5,469 217 1,905 1,496 409

Rural 18,187 16,350 1,837 5,670 5,456 214 1,863 1,464 399

Urban 4,587 3,945 642 16 13 3 42 32 10

0173 Dangtol Total 2,575 2,170 405 256 224 32 463 390 73

Rural 1,977 1,659 318 255 224 31 463 390 73

Urban 598 511 87 1 - 1 - - -

0174 Boitamari Total 4,961 4,409 552 1,332 1,259 73 423 320 103

Rural 4,807 4,279 528 1,326 1,253 73 411 314 97

Urban 154 130 24 6 6 - 12 6 6

0175 Srijangram Total 3,058 2,723 335 1,174 1,138 36 259 202 57

Rural 3,058 2,723 335 1,174 1,138 36 259 202 57

Urban - - - - - - - - -

0176 Tapattary Total 3,800 3,530 270 1,417 1,385 32 179 153 26

Rural 3,800 3,530 270 1,417 1,385 32 179 153 26

Urban - - - - - - - - -

0177 Manikpur (Part) Total 4,545 4,159 386 1,498 1,456 42 551 405 146

Rural 4,545 4,159 386 1,498 1,456 42 551 405 146

Urban - - - - - - - - -

0178 Sidli-Chirang

(Part) Total 90 79 11 - - - - - -

Rural - - - - - - - - -

Urban 90 79 11 - - - - - -

URBAN

801620 Bongaigaon (MB) Urban 2,756 2,357 399 8 6 2 28 24 4

New Bongaigaon

Rly.

301325 Col. (CT) Urban 598 511 87 1 - 1 - - -

Chalantapara Pt IV

301473 (CT) Urban 154 130 24 6 6 - 12 6 6

801621 Abhayapuri (TC) Urban 989 868 121 1 1 - 2 2 -

301806 B.R.P.L. Township (CT) Urban 90 79 11 - - - - - -






3.11.2 Demographic Details of Settlements in the Study Area

A House Holds

In the settlements located in the study area, there are total 1,50,018 households as per

census records 2011.

B. Population

As per census records, the population of settlements in the study area is 7,38,804 nos. The

male population constituted nearly 50.8% persons while the female population is 49.1 % of

the total population.

INDUSTRIAL CATEGORY

District/ CD Block/ Agricultural labourers Household industry workers Other workers Rural/

Town Persons Males Female

s

Persons Males Females Persons Males Females Urban

2 30 31 32 33 34 35 36 37 38 3

Bongaigaon - District 24,914 19,359 5,555 4,756 3,453 1,303 95,234 82,200 13,034 Total

24,623 19,131 5,492 4,284 3,081 1,203 63,119 54,527 8,592 Rural

291 228 63 472 372 100 32,115 27,673 4,442 Urban

Dangtol 4,129 3,155 974 881 659 222 19,484 16,430 3,054 Total

4,109 3,140 969 856 650 206 15,511 12,948 2,563 Rural

20 15 5 25 9 16 3,973 3,482 491 Urban

New Bongaigaon Rly.

Col. (CT) 20 15 5 25 9 16 3,973 3,482 491 Urban

Boitamari 5,172 3,670 1,502 930 728 202 15,995 13,882 2,113 Total

5,103 3,622 1,481 898 705 193 14,961 12,910 2,051 Rural

69 48 21 32 23 9 1,034 972 62 Urban

Chalantapara Pt IV

(CT) 69 48 21 32 23 9 1,034 972 62 Urban

Srijangram 5,701 4,270 1,431 1,093 624 469 9,741 8,149 1,592 Total

5,701 4,270 1,431 1,093 624 469 9,741 8,149 1,592 Rural

- - - - - - - - - Urban

Tapattary 4,125 3,644 481 580 389 191 10,869 9,659 1,210 Total

4,125 3,644 481 580 389 191 10,869 9,659 1,210 Rural

- - - - - - - - - Urban

Manikpur (Part) 5,585 4,455 1,130 857 713 144 12,037 10,861 1,176 Total

5,585 4,455 1,130 857 713 144 12,037 10,861 1,176 Rural

- - - - - - - - - Urban

Sidli-Chirang (Part) 4 3 1 6 2 4 2,146 1,818 328 Total

- - - - - - - - - Rural

4 3 1 6 2 4 2,146 1,818 328 Urban

B.R.P.L. Township (CT) 4 3 1 6 2 4 2,146 1,818 328 Urban

URBAN

Bongaigaon (MB) 191 156 35 312 266 46 20,213 17,399 2,814 Urban

New Bongaigaon Rly.

Col. (CT) 20 15 5 25 9 16 3,973 3,482 491 Urban

Chalantapara Pt IV

(CT) 69 48 21 32 23 9 1,034 972 62 Urban

Abhayapuri (TC) 7 6 1 97 72 25 4,749 4,002 747 Urban

B.R.P.L. Township (CT) 4 3 1 6 2 4 2,146 1,818 328 Urban






C. Sex Ratio

As per census records, sex ratio is defined as the number of females per 1000 males. As per

census records, sex ratio in settlements located in the study area are 966.

D. Schedule Caste

In the study area, scheduled castes population of 11.21 %, is 11.31 % amongst males and

11.09% amongst females.

E. Schedule Tribe

In the study area, scheduled tribes population is 2.55 %, 2.50% amongst males and 2.61%

amongst females of the total population of the area.

F. Literacy

In the study area 69.74 % is literate, 74.87% amongst males and 64.43% amongst females.

3.11 Traffic Analysis

IOCL BGR Complex is of 840 acres land attached to the NH 31, NH 31C passes through the

project study area; they are at a distance of 7 KM from New Bongaigaon Railway station No

of vehicles passing per day on NH-31 outside IOCL BGR are mentioned below.






Vehicle

Type

Morning time (4:00 AM to

12:00PM)

Afternoon time (12:00 PM to 8:00 PM)

Evening & Night

time (8:00 PM to

4:00 AM)

Total Vehicles/day

(approx)

West East West East West East West East

Buses 35 50 20 25 50 55 105 130

Trucks

/Trolleys

40 50 60 70 70 80 170 200

Tankers 30 35 40 50 35 40 105 125

Cars 150 160 180 200 120 140 450 500

Two

wheelers

250 270 300 320 320 330 870 920

Total 505 565 315 305 595 645 1415 1515

• The BGR, IOCL complex, has been in existence since the year 1973, now has a well-

developed infrastructure for utilities. BGR has already provided internally the facility

for parking of vehicles, tankers Buses and trucks.

• The proposed project surroundings already has general infrastructure facilities such

as railways siding for dispatch of products, approach road.

• No roads are designed with sharp/curved turns in the company premises. The major

part of transportation of raw products and manufactured products is done by

railways present in the BGR premises. Hence there are no chances of traffic

congestion within and outside the BGR premises.






CHAPTER 4











CHAPTER 4

ANTICIPATED ENVIRONMENTAL IMPACTS & MITIGATION MEASURES

4.1 Introduction

The anticipated environmental impacts on various components of environment due to

proposed capacity enhancement of the crude processing refinery at Bongaigaon can be

assessed in terms of i) physical environment ii) biological environment, and iii) demographic,

land use and socioeconomic environment. For proper assessment of significance and

magnitude of environmental changes in construction and operation of the existing refinery

the impacts are analyzed for each environmental parameter. An assessment is made both

for adverse and beneficial impacts in following section.

4.2 Physical Environment

4.2.1 Soil


During the expansion, revamp phase the company will implement the following projects:

i. Crude processing capacity enhancement (from 2.35 MMTPA to 2.7 MMTPA)

ii. DHDT capacity enhancement (from 1,200 TMTPA to 1,800 TMTPA) to meet

BS-V/VI HSD specification

iii. CRU-MSQ revamp to meet BS-V/ VI MS specification

iv. Selective Desulphurisation (SDS) Unit

v. INDMAX Project along with Indmax Gasoline De-Sulphurisation Unit.

There will be a small amount of construction wastes, such as, metal cutting, and debris

during erection of equipments like Columns, Vessel Pumps which may contaminate soil at

the site of construction. However, the extent of contamination will not be significant. These

wastes will not normally contaminate ground water. Their impact on soil and surface water

will be restricted to the construction period in small area around the construction site

during heavy rainfall only. Approx 500 kg of canteen waste will be generated during the

construction phase which will be handled by existing labour canteen facilities

Mitigation Measures

• Collection of metal cuttings, oil, grease and construction debris from the site. It will be

disposed off scientifically to approved vendors.

• Solid waste collection bins at the site.

• Maintaining house keeping at construction site.

• Canteen waste will be handled by existing canteen facilities.







During operation phase of existing plant and implementing the above mentioned projects;

large amount of Solid waste like Spent Catalyst and equilibrium catalyst will be generated.

Very negligible only about 5 kg solid wastes will also be generated from office and canteen.

Used oil will be generated at the time of maintenance of DG sets. For collection,

management and disposal of solid and hazardous wastes from the plant, necessary

mitigation measures will be taken same as for existing Plant.

Mitigation Measures

• Maintaining housekeeping at plant.

• The Spent Catalyst wastes from the different units will be replaced once in 1, 5, 6 and

10 years depending on its requirement. The spent catalyst will be disposed to

authorized CPCB recycler.

Sr.

no.

Particulars Quantity Remarks Disposal

1. DHDT catalyst 31 MT

catalyst (for

5 years)

Replacement once in

5 years

Disposal to CPCB

registered recycler

2. CRU catalyst 9 MT catalyst

(for 5 years)

Replacement once in

5 years

Platinum will be

recovered

Disposal to CPCB

registered recycler

3. MSQ catalyst 27 MT

catalyst (for

5 years)

Replacement once in

10 years

Platinum will be

recovered

Disposal to CPCB

registered recycler

4. INDMAX FCC

catalyst

600 MTPA

catalyst

• Continuous

regeneration

of catalyst

make –up rate

is 1.8 TPD

Disposal to CPCB

registered recycler

5. HDS catalyst 9 MT catalyst

(for 6 years)

Replacement once in

6 years

Disposal to CPCB

registered recycler

6. SDS catalyst 3 MT catalyst

(for 5 years)

Replacement once in

5 years

Disposal to CPCB

registered recycler

• Additional Approx. 5-10 kg day municipal wastes (paper plastic, food wastes, etc) will

be generated, which will be collected and segregated. Recyclable wastes like paper

and plastic wastes will be sent for recycling. Biodegradable wastes like food and

vegetable wastes will be disposed compost pit. Non- biodegradable and non-

recyclable wastes will be sent to common landfill site.






• From the maintenance of DG sets, 400 litres used oil is generated, which is categorized

as hazardous wastes and handed over to CPCB authorized oil recyclers.

4.2.2 Water Quality


During the construction phase the demand of drinking water and construction water will be

meet from existing source. Adequate drinking water, hygiene and sanitation facilities will be

provided to the workers.

The construction phase may result in minor soil erosion from the plant site, as it will clear of

ground flora during plant erection. The run off from the construction site during rainfall may

cause some increase in the quantity of suspended solids and turbidity in the runoff in

natural drain. However, this impact will be of temporary nature and may not last as soon as

excavated soil established and construction debris is disposed off properly.

Mitigation measures

• Excavation for foundations of structures/vessels will be carried out during dry season.

• Construction debris will be collected and disposed properly daily basis.

• Sanitary facilities for workers will be provided.


Only 40 m3/hr of water daily will be required for the INDMAX unit. While the CDU-II, DHDT,

SDS & CRU-MSQ units will not require any additional water.

• BGR has installed Tertiary Treatment Plant to facilitate reuse of effluent water inside

the complex as cooling water and firewater makeup.

Total water consumption after expansion will be 370 Cum/day and entire quantity of

treated effluent will be used for cooling tower make up and irrigation purpose. Thus

achieving Zero discharge status

• Waste water from canteen at the Plant will be treated in oil and grease trap followed

by septic tank and soak pits

4.2.3 Climatology and Meteorology

The construction and operation phase of proposed expansion of existing Plant will have no

impact on meteorology of the area. Therefore, no mitigation measure is required.

Air Quality


During the expansion, revamp phase, Activities like cleaning, levelling, grading, construction,

metal cutting, and erection of equipments like Columns, Vessel Pumps will be carried out.






A certain amount of particulate matter will be generated by truck movements during the

construction phase. However, the suspended particulate matter in ambient air as a result of

construction activities may be relatively coarse and will be settled within a short distance.

Therefore, the impact will be restricted within the close vicinity of the construction activity

for short period of time.

Mitigation Measures

• Cordoning off construction area by tin sheets & garden net

• Dust suppression measures like water sprinkling as per requirement.


• During operation there will be NOx, SOx stack emissions from INDMAX FCC generator,

IGHDS unit, CDU-II, DHDT unit, and CRU unit, plant after expansion, The major SOx

emissions from INDMAX unit will be controlled by installing SDS unit at plant. All the

Stack heights will be designed as per CPCB guidelines.

• Fugitive emissions of hydrocarbon may result from unloading hose, faulty bottling,

leaking cylinders and minor leaks. Gas leak detectors, and Floating roof storage tanks

will be provided at strategic locations to detect concentration of hydrocarbon in the

premises.

• DG sets installed at BGR plant, they are operated occasionally in case of power failure

and these are not regular source of gaseous emissions.

• Tankers/trucks/vehicles have pollution under control (PUC) certificates. Regular

maintenance of Diesel tankers/trucks will be ensured.

4.2.4 Noise


During construction phase, metal cutting, and erection of equipments like Columns, Vessel

Pumps, cold cutting, hammering, vehicle movement, Rotary etc can generate noise., DG sets

may be major sources of noise generation during. Relatively high noise levels will be

generated during construction phase. Anticipated noise levels from various sources are as

given below in Table 4.1:

Table 4.1: Anticipated Noise Levels from Various Sources

Sn. Sources Anticipated Noise Levels

1. DG set 90 dB(A)

2. Metal cutting and bending 80 dB(A)

3. Hammering 85 dB(A)

4. Erection of equipment 75 dB(A)






Generation of noise levels from above sources will be intermittent in the nature. The noise

level generated from the construction site would decrease with increase in distance from

the source due to the wave divergence effect.






Modelling for Noise Emissions from Construction Site

For dispersion modelling of noise, standard mathematical model for sound wave

propagation have been 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 from the source is expected due to atmospheric effect or

its interaction with objects in the transmission path.

For hemispherical sound wave propagation through homogeneous loss free medium, one

can estimated noise levels at various locations due to different sources using model based

on first principles, as per the following equation:

Noise (Receptor) = Noise (Source) - 20 Log [distance (Receptor) /distance (Source)]

The combined effect of all the sources then can be determined at various locations by the

following equation.

Lp (total) = 10 Log (10(Lp1/10) +10(Lp2/10)+10(Lp3/10)

Where Lp1, LP2, LP3 are noise pressure levels at a point due to different sources.

The resultant maximum noise level from site is calculated as 85 dB (A). Assuming no

environmental attenuation factors, noise modelling has been done which shows that noise

level at different distance from the site has been shown in Table 4.2:

Table 4.2: Noise Level at Various Distances

Noise Levels (dB (A)) Distance from Source (m)

85 0.9

80 1.5

75 2.7

70 4.8

65 8.5

60 15.1

55 26.9

50 47.9

Graphical presentation of noise attenuation during construction site is shown in Figure 4.1.






Figure no.4.1: Noise levels during construction phase

The above noise modelling results show that the noise levels will remain below acceptable

level within short distance inside the BGR plant. Further, the resultant noise level will mingle

with the background noise level (assumed to be 55 dB (A) at 26.9 m during day time. The

above noise levels are without mitigative measures. With the mitigative measures, the noise

levels will be further restricted within very short distance from the BGR plant.

Mitigation Measures

• Use of ear muff and ear plugs to workers working in high noise area.

• Acoustic enclosures are already fitted with DG sets.

Therefore, no significant impact is anticipated on noise levels during construction phase of

proposed expansion, revamp at BGR plant.


Noise generation is expected from piling process and rotating machinery, equipments. The

other sources are pumps, compressor, turbines. DG sets are to be operated only during grid

power failure.

Mitigation Measures

• Equipment specification and installation of acoustic enclosure with DG sets ensure low

level of noise generation.

• All the Diesel Tankers and trucks are essentially fitted with silencers to control noise

generation.

• Planting trees and developing and maintaining green belt area which works as noise

barrier.

• Quarterly Noise surveys are conducted and abnormalities are resolved.

Therefore, impact on noise levels of the study area due operations at the BGR plant will be

insignificant.

4.2.5 Terrestrial Ecology


The site of construction is within premise of existing refinery. The area which is earmarked

for construction of the plants is having 450 nos. of trees (approx.).


BGR carries out massive tree plantation in the company premises and at the periphery

(planted around 500 trees from Oct 14 to March 15, BGR has 84,545 no. of plants as per

census). During operation phase, no impact on green belt of the plant premises and ecology

of the study area is anticipated. Growth of plantation and development of green belt at the

plant is likely to improve the flora and fauna at the site.

4.3 Demographic, Land Use And Socio-economic Environment

4.3.1 Demographic

During construction phase, around 5,430 workers will be deployed, mostly from local area.

The construction activity of proposed plant will not displace any person.

During Operation of proposed BGR plant will not require large work force and only 20 skilled

workers will be sufficient to operate and handle the plant. Therefore, large scale






immigration will not take place and the impact on demography of the area will be

insignificant.

Land Use

The construction, revamping of BGR plant will have no impact on land use in the study area,

as land for construction of proposed plant is already available within the existing refinery

premises.

Land Use Break Up:

S. No. Particulars Total Area

(Sq.m.)

% of Total

Area

1 Plant Area 34,43,826 75.18%

2 Township 1,137,168 24.82%

TOTAL 45,80,994 100.0%

The project will be put up in the existing land area and no new land is required.

4.3.2 Socio-economic

4.3.2.1 Economic Impacts

The construction and operation of the plant will have some beneficial impact due to

increase in incomes as local unskilled, semiskilled and skilled persons as they will gain some

direct and indirect employment In view of the small manpower and support facility

requirements, the beneficial impact due to the operation of the new proposed changes in

the BGR plant is likely to be marginal. However, this expansion and revamping is going to

impact positively on the production capacity of IOCL, thus by serving larger markets and

serving the Indian economy.

4.3.2.2 Social Impacts

Since the immigration of work force during construction and operation of the proposed

expansion, revamping and implementation of new technologies at the plant will be likely to

be very small, the impact on facilities and cultural aspects are expected to be insignificant.

4.3.4 Sustainable Development and Environmental Protection

At the centre of the socio-economic impact lies the question of whether economic

development and growth can go hand in hand with environmental protection. The

expansion, revamping activity and implementation of new technologies at the BGR plant is

not likely to have any negative impact if, the proposed mitigation for environmental

management are implemented by the IOCL management. The proposed changes will have

definite beneficial impacts, even though marginal, on infrastructures facilities, gross

economic product, employment opportunities, socio-economic aspects of the area.






CHAPTER 5











Chapter 5

Alternative Analysis

5.1 Introduction

The proposed project at IOCL, Bongaigaon, Assam is an existing unit. They want to expand

the capacity, revamp units and implement INDMAX technology with pollution control

measures.

The consideration of technological alternatives for proposed expansion and revamping is

one of the more proactive side of environmental assessment - enhancing the project

through examining options instead of only focusing on the more defensive task of reducing

adverse impacts of a single option of the project. This requires the systematic comparison of

feasible alternatives for technology and operational alternatives. Alternatives are compared

in terms of their potential environmental impacts, capital and recurrent costs, suitability

under local conditions, etc.

The examining alternative means of carrying out a project involves answering the following

three questions:

(i) What are the alternatives?

(ii) What are the environmental impacts associated with each alternative?, and

(iii) What is the rationale for selecting the preferred alternative?

5.2 Alternative Technology

IOCL is implementing the following projects:


• DHDT capacity enhancement from 1,200 TMTPA to 1,800 TMTPA to meet BS-VI HSD

specification.

• CRU-MSQ revamp to meet BS- VI MS specification.



There is no alternative technology available as of today.

Project Justification

Ministry of Environment & Forests (MoEF) has earlier granted Environmental Clearance to

erstwhile Bongaigaon Refinery & Petrochemicals Limited” (BRPL), Dhaligaon vide letter no.

J-11011/9/2008/- IA II (I) dated 2nd September, 2008). for the “Indmax Project (INDMAX

FCC Unit along with Indmax Gasoline De-Sulphurisation Unit) to eliminate production of

black oils (LDO, LVFO & LSHS) and Naphtha in District Chirang, Assam. However, the project

could not be implemented due to unfavourable project economics during the period of

validity of the Environment Clearance.






In view of the Auto-Fuel Policy Vision 2025, the Refineries will be required to supply fuels

meeting the BS-IV specification fuels by 1st April 2017 and BS-V/VI specification by 1st April,

2019.

In order to meet the requirements as mentioned above, BGR will be implementing project

consisting of Indmax, Crude capacity enhancement from 2.35 to 2.7 MMTPA, DHDT capacity

enhancement capacity from 1200 TMTPA to 1,800 TMTPA, CRU-MSQ revamp and installing

Selective Desulphurisation (SDS) Unit.

After implementation of this project the BGR refinery plant will be capable of manufacturing

HSD which will conform the BS-VI specifications. The new HSD (BS-VI) will cut the nitrogen

dioxide emissions by 68% and 25% from diesel and petrol cars respectively. This will

significantly reduce the concentration of cancer causing particulate matter by 80 %

5.3 Alternative Site

Project Location

The Plant is situated at a latitude of 26o 31' N and longitude of 90o 31'E, and is at a distance

of 190 km by road from Guwahati. The site is approachable by rail as well as road. The

nearest Airport is at Guwahati, which is well connected by the Road network. The

topography of the study area is plain, which is traversed by three meandering rivers viz., Aie,

Tunia and Kujia. On the Eastern side of the study area flows the river Aie in the South - East

direction. The western boundaries of the study area is having major tributaries of the river

Brahmaputra. Apart from these three rivers, there are about four lakes in the study area.

Nakkatti, Bhumeshwar and Kakaijana are the important hillocks within the study area

ranging in height from 122 to 212 m above mean sea level. The area under the Reserve

Forests accounts for less than 5 percent of the Study area. These forests are Nakatti,

Kakaijana and Bhumeswar (to be declared) located at 7.5, 9.5, 7.8 km distance from the

plant in South, South -East and South - West directions respectively

Site Justification

The site selected for expansion of various units and implementation of INDMAX technology

within Bongaigaon complex has good approach roads, and close to offsite facilities and

utility tap off points.

Apart from above, other advantages such as sharing of control room, the existing facilities of

road, water, and electricity shall be utilized.

The plot surrounding already has general infrastructure facilities such as railways siding for

dispatch of products, approach road, and pipeline for disposal of effluents. Other

infrastructure support for project such as hydrogen source, tank farm, and utility block,

Control Room, Crude Distillation Unit (CDU) and Delayed Coker Unit (DCU) already exists.

General facilities such as warehouse laboratory, maintenance shops, safety and fire fighting






unit and equipment also exist. The Bongaigaon complex, which has been in existence since

the year 1973, now has a well-developed infrastructure for utilities. The site of construction

is within premise of existing refinery. The area which is earmarked for construction of the

plants is having 450 nos. of trees (approx.).

No significant stress is therefore foreseen from associated developments involving land-take

and material management for infrastructure expansion.

Since the fuel to be used for the proposed project is sweet fuel gas with minimum use of

fuel oil and the fuel gas generated in DHDT and Reformer shall be consumed internally,

transport of undesirable emissions into the atmosphere are unforeseen. A new hydrocarbon

flare system and a new acid flare system have been considered for the proposed project to

further reduce the impacts of unburnt gaseous products arising from the project operations.

With the reduction in the sulphur content of the diesel and setting up of the SRU (98%

recovery as per revised standards of CPCB for Refinery) to recover the solidified sulphur

from the liquid sulphur, the possibility of increased SO2 content of the emissions dispersing

in the ambient environment is likely to be reduced.

The land required for the project is 38 hectares. This required area is available within the

complex. The site has been selected for efficient integration of the proposed unit with the

available units. The unit when implemented would be close to the other refinery units,

thereby giving flexibility in operation and maintenance of the unit by the

operation/maintenance staff of those plants. Hence the project site area itself is sufficient

to complete the plant expansion, revamping and implementation of new technologies

activities. There is no requirement any alternative site.

5.4 Alternatives for Storage

The refinery, located in Assam state, already has a well developed infrastructure set up

within the premises. There are already various capacity tanks provided onsite and offsite for

storage of manufactured fuels products. Hence no other infrastructure set up and storage

facility is required.

5.5 Alternative for risk reduction at petrochemical refinery:

Virtually all the health hazards common to industry may be present oil industry, namely,

• Chemical hazards (toxic, corrosive, irritant sensitizing substances and possible

carcinogens);

• Physical hazards (noise, vibration, various forms of radiation );thermal extremes

• Biological hazards (food poisoning. Malaria);

• Ergonomic hazards (manual handling activities, workstations, VDUs); and






• Psychosocial hazards associated with the work atmosphere hours (Isolation, of work,

tours, shifts, work load and content, fatigue, etc all contribute to psychological stress

The Risk Assessment (RA) of the units has been done to identify the key hazards and risks.

By conducting this type of RA it should be emphasized that the focus is on the major, worst-

case, hazards and impacts from surrounding area of these units, essentially in order to

prioritise the off-site risks and potential impacts to the public.

Occupational risk, health survey and management, is carried out logically, systematically and

methodically of identifying, analyzing, assessing, mitigating, monitoring and communicating

health risks associated with an activity, function or process in a way that will enable

organizations to control health risk.

The management system for occupational health provides the framework for the process of

identifying hazards, assessing associated risks, taking action and reviewing the outcome. The

objective is to prevent occupational diseases and to promote the employee health. In

occupational health, the deliverable is the absence of occupational diseases resulting in a

healthy and productive worker. Therefore all the occupational risks will be mitigated at the

BGR refinery.






CHAPTER 6






CHAPTER 6

ENVIRONMENTAL MONITORING PLAN 6.1 Introduction

Regular monitoring program for the environmental parameters is essential to take account

the changes in the environment due to expansion, revamping construction at existing Plant.

To ensure the effective implementation of the mitigation measures and environmental

management plan during operation phase of plant after expansion and revamp, it is

essential that an effective environmental monitoring plan to be designed and followed

during operation phases.

The objectives of environmental monitoring plan for Bongaigaon Refinery are:

• To verify the results of the impact assessment study in particular with regards to

proposed expansion activity;

• To follow the trend of concentration values of the parameters which have been

identified as critical;

• To check or evaluate the efficiency of the mitigation measures; and

• To ensure that new parameters, other than those identified in the impact

assessment study, do not become critical at plant after expansion.

The environmental monitoring is the primary tool for assessing the prevailing quality of air,

water, noise, land etc. The environmental monitoring helps in suggesting and taking

corrective course corrections, monitored parameters are exceeding. The monitoring of

various environmental parameters for ambient air quality, water quality, noise levels, soil

quality will be carried out on a regular basis at and around the existing plant after expansion

to ascertain the following:

• Pollution caused due to operations after the expansion, revamping and

implementation of fully new unit within existing refinery premises.

• Change in environmental quality within and outside the existing Plant.

• To assess environmental impacts after expansion of existing plant.

• Evaluate the efficiency of pollution control measures installed.

The environmental monitoring shall be periodic and comply with the promulgated

standards. The frequency of monitoring of various environmental components and

frequency to be monitored is given in Table 6.1.

6.2 Environmental Monitoring Schedules

To check the efficacy of the adopted mitigation measures and environmental Management

plan, post project monitoring is carried out for various environmental parameters. In case,

the monitored results of environmental parameter are found to exceed the

allowable/stipulated values, the Environmental Management Cell suggests remedial actions

and gets these suggestions implemented through the concerned personnel.






6.2.1 Ambient Air Quality (AAQ) Monitoring

Ambient air quality parameters suggested during operation phase of the proposed

expansion within existing plant are Particulate Matters (PM2.5), Particulate Matter (PM10),

Nitrogen Dioxide (NO2), Sulphur Dioxide (SO2), Carbon Monoxide (CO), HC and VOC. These

are to be monitored at designated locations starting from the commencement of

construction activities. Data should be generated 24 hourly during operation phase at

identified locations in accordance to the National Ambient Air Quantity Standards.

During operation phase, the major source of air emissions will be from DHDT unit, CRU -

MRQ unit and Indmax unit along with the vehicular emissions from Plant. Six monthly

ambient air quality monitoring should be carried out at boundaries of Plant. The continuous

Ambient air quality monitoring station is also to be envisaged.

6.2.2 Water Quality Monitoring

At Bongaigaon Refinery, there will not be any source for ground and surface water

contamination during construction and operation phases. However, ground water sampling

and analysis can be carried out at the Plant during operation phases. Only 40 m3/hr of water

daily will be required for the INDMAX unit. While the CDU-II, DHDT, SDS & CRU-MSQ units

will not require any additional water. BGR has installed Tertiary Treatment Plant to facilitate

reuse of effluent water inside the complex as cooling water and firewater makeup.

The locations, duration and pollution parameters to be monitored and necessary

institutional arrangements are detailed in the environmental monitoring plan. The

monitoring of the ground water quality will be carried out at one location in accordance to

Indian Standard Drinking Water Specification-IS 10500:2012 for relevant parameters as

directed by State Pollution Control Board (APCB).

6.2.3 Noise Levels Monitoring

During the construction phase, metal cutting, and erection of equipments like Columns,

Vessel Pumps, Vehicles and trucks movements will generate noise

The measurement of noise levels would be carried out at suggested locations in accordance

to the Ambient Noise Standards formulated by Ministry of Environment, Forest and Climate

Change (MoEF&CC). Noise levels would be monitored on twenty-four hourly basis. Noise

measurements should be recorded at “A” weighted frequency using a slow time response

mode of the measuring instrument. The noise measurement location and duration are

detailed in the environmental monitoring plan.

6.4 Environmental Monitoring Plan

Environmental monitoring plan for operation phases of the existing Plant including

installation INDMAX and other units is given in Table 6.1.



Assam


Table 6.1: Environmental Monitoring Plan for BPRL Plant of IOCL

Environmental

Component

Project stage Parameter Standards Location Duration /

Frequency Implementation Supervision

Ambient Air Construction

Phase PM2.5, PM10,

SO2, NO2, CO National

Ambient

Quality

Standards

At the plant site Continuous 24-

hourly Environmental Cell

of BGR or MoEF&CC/

APCB/ NABL

approved

monitoring agency

BGR

Operation Phase HC and VOC -- Near CDU-II,

DHDT, SDS, CRU-

MSQ and INDMAX

units areas.

Continuous 24-

hourly once six

monthly

Environmental Cell

of BGR or MoEF&CC

/ APCB /NABL

approved

monitoring agency

BGR

PM2.5, PM10,

SO2, NO2, CO &

HC on

Boundary of

LPG Plant

National

Ambient

Quality

Standards

At boundary wall

in upwind and

down wind

direction at Plant

Continuous 24-

hourly once six

months

BGR through

MoEF&CC/ APCB/

NABL approved

monitoring agency

BGR

Water Quality Construction

Phase As per IS:

10500:2012 for

relevant

parameters

As Water

quality

standards (IS 10500:2012)

At the site, Near

expansion,

revamping CDU-II,

DHDT, SDS, CRU-

MSQ and

construction of

INDMAX units

areas.

Six Monthly BGR through

MoEF&CC/ APCB/

NABL approved

monitoring agency

BGR



Assam


Environmental

Component

Project stage Parameter Standards Location Duration /

Frequency Implementation Supervision

Operation Phase As per IS:

10500:2012 for

relevant

parameters in

consultation

with MPCB

As Water

quality

standards (IS 10500:2012)

Within the site Six Monthly BGR through

MoEF&CC/ APCB/

NABL approved

monitoring agency

BGR

Noise

Measurements Construction

Phase Noise Level in

dB (A) As per National

Noise

standards

At the site of

expansion,

revamping &

installation

24-hourly

measurement,

once quarterly

during the

construction

phase

BGR through MoEF/

APCB/ NABL

approved

monitoring agency

BGR

Operation Phase Noise Level in

dB (A) As per National

Noise

standards

At site, Trucks

Travelling areas

within the plants

24-hourly

measurement,

once six months

BGR through

MoEF&CC/MPCB/

NABL approved

monitoring agency

BGR






6.5 Health, Safety & Environmental Management Cell

In order to implement the environmental management program efficiently within the

organization, periodical monitoring as per statutory guidelines and mid course

corrections/actions, if required based on the environmental monitoring results,

management intends to establish environmental cell for successful implementation. The

roles & responsibilities are clearly defined among the personnel within the environmental

cell. The responsibilities of personnel are given in Table 6.2.

Table 6.2: Responsibilities of Personnel of the HSE Department

Designation Responsibility

Chief Manager Heading the Health, Safety & Environment department. Overall in-charge of Monitoring of Environmental parameters and

effectiveness of environmental protective measures taken for

environmental management

Senior Managers To Monitor, analyze all Environmental parameters and

effectiveness of environmental protective measures taken and

decide about the additional protective measures in safeguarding

the overall ecology and environment.

6.6 Statutory Returns and Compliance Reports

The statutory returns and compliance reports here below are to be submitted to the

Ministry of Environment & Forests (MoEF & CC), State Pollution Control Board (Assam) and

Central Pollution Control Board.

• Submission of half yearly compliance report in respect of the stipulated prior

environmental clearance terms and conditions in hard and soft copies to the

regulatory authority concerned, on 1st June and 1st December of each calendar year.

• Submission of environmental statement for the financial year ending 31st March to

the concerned Assam Pollution Control Board on or before 30th September every

year.

• Submission of Water Cess returns in Form 1 as per Rule 4 (1) of Water (Prevention &

Control of Pollution) Cess Rules 1978 on or before the 5th of every calendar month.






CHAPTER 7











CHAPTER 7

RISK ASSESSMENT & HAZARD IDENTIFICATION

7.1 Introduction

Industrial plants deal with materials, which are generally hazardous in nature by virtue of

their intrinsic chemical properties or their temperature or pressure of operation or a

combination of these. Fire, explosion, hazardous release or a combination of these are the

hazards associated with industrial plants. These have resulted in the development of more

comprehensive, systematic and sophisticated methods of safety engineering such as hazard

analysis and risk assessment to improve upon the integrity, reliability and safety of industrial

plants.

The primary emphasis in safety engineering is to reduce risk to human life and environment.

The broad tools attempt to minimize the chances of accidents occurring. Yet, there always

exists, no matter how remote, that small probability of a major accident occurring. If the

accident involves highly hazardous materials in sufficient large quantities, the consequences

may be serious to the plant, to surrounding areas and the populations therein.

Risk Assessment & Hazard Identification




The first step in risk assessment is identification of hazards. Hazard is defined as a physical or

chemical condition with the potential of accident which can cause damage to people, property or

the environment. Hazards are identified by careful review of plant operation and nature of materials

used. The various scenarios by which an accident can occur are then determined, concurrently study

of both probability and the consequences of an accident is carried out and finally risk assessment is

made. If this risk is acceptable then the study is complete. If the risk is unacceptable then the system

must be modified and the procedure is restarted.

Scope of Risk Analysis

The scope of risk analysis study includes:

• Identify potential hazard sections of the plant, which are likely to cause damage to

the plant, operating staff and the surrounding communities in case of any accident

due to the proposed plant facilities.

• Assess overall damage potential of the hazardous events in relation to main plant

and environment.

• Assessment of total individual risk.

• Recommended emergency preparedness plan to mitigate the effects of any accident.

Risk Analysis

Risk Analysis of any plant / installation handling hazardous materials includes –






Hazard Identification

● Identify potentially hazardous materials that can cause loss of human life/injury, loss

of properties and deteriorate the environment due to loss of containment.

● Identify potential scenarios, which can cause loss of containment and consequent

hazards like fire, explosion and toxicity.

Consequence Analysis

● Analysis of magnitude of consequences of different potential hazard scenarios and

their effect zones.

● Consequence analysis is a measure of potential hazards and is important for taking

precautionary measures for risk reduction as for well as mitigation of effect in case of

such accidents happening.

This report has been prepared by applying the standard techniques of risk assessment and

the information provided by IOCL. Based on the Risk Assessment, Disaster Management

Plan (DMP) has been prepared.

Glossary of Terms used in Risk Assessment

The common terms used in Risk Assessment and Disaster Management are elaborated

below:

“Risk” is defined as a likelihood of an undesired event (accident, injury or death)

occurring within a specified period or under specified circumstances. This may be

either a frequency or a probability depending on the circumstances.

“Hazard” is defined as a physical situation, which may cause human injury, damage to

property or the environment or some combination of these criteria.

“Hazardous Substance” means any substance or preparation, which by reason of its

chemical or physico-chemical properties or handling is liable to cause harm to human

beings, other living creatures, plants, micro-organisms, property or the environment.

“Hazardous Process” is defined as any process or activity in relation to an industry,

which may cause impairment to the health of the persons engaged or connected

therewith or which may result in pollution of the general environment.

“Disaster” is defined as a catastrophic situation that causes damage, economic

disruptions, loss of human life and deterioration of health and health services on a

scale sufficient to warrant an extraordinary response from outside the affected area

or community. Disaster occasioned by man is factory fire, explosions and release of

toxic gases or chemical substances etc.

“Accident” is an unplanned event, which has a probability of causing personal injury

or property damage or both.






“Emergency” is defined as a situation where the demand exceeds the resources. This

highlights the typical nature of emergency “It will be after experience that enough is

not enough in emergency situations. Situations of this nature are avoidable but it is

not possible to avoid them always.”

“Emergency Preparedness” is one of the key activities in the overall Management.

Preparedness, though largely dependent upon the response capability of the persons

engaged in direct action, will require support from others in the organization before,

during and after an emergency.

7.2 Rapid Risk Assessment at Bongaigaon Refinery Plant

RRA study identifies the hazards associated with the proposed project, analyses the

consequences, draws suitable conclusions and provides necessary recommendations to

mitigate the hazard/ risk.

Now BONGAIGAON REFINERY PLANT is enhancing the capacity, revamping & installing new

technology at the plant. The changes are as follows:


• DHDT capacity enhancement from 1,200 TMTPA to 1,800 TMTPA to meet BS-VI

HSD specification.

• CRU-MSQ revamp to meet BS- VI MS specification.



•

This RRA study is based on the information made available in the process design basis of

the CDU, DHDT, CRU-MSQ, INDMAX and SDS units.

7.3 Objective and Scope of Study

The main objective of the rapid risk analysis study is to identify the potential hazard

scenarios and assess the impact of major accidental hazards from the proposed Diesel

Hydro Treatment Project on the population and property within and outside the battery

limit of the facilities. The results are also useful in developing a meaningful emergency plan

and to serve as a powerful training tool.

The following facilities are within the scope of study;

• Crude Distillation unit (CDU-II unit 1.35 MMTPA)

• Diesel Hydro Treatment Facilities (DHDT Unit 1.8 MMTPA)

• CRU unit (200 TMTPA)

• MSQ unit (224 TMTPA)

• INDMAX FCC unit along gasoline desulphurisation unit (312 TMTPA)

7.4 General:

Description of Facilities:






Diesel Hydrotreating Unit

The objective of Diesel Hydrotreatment Unit (DHDT) is to treat and upgrade the existing

quality of HSD to meet the stringent new quality specifications of HSD with respect to

sulphur content, cetane number, Cetane index, poly aromatics content, stability, etc.

Bongaigaon Refinery Plant proposes to improve the quality of HSD with respect to sulphur

content from the present level of 0.17 to as low a figure as 0.005 wt%, cetane number from

the present level of 45 to 51.

The process flow scheme of DHDT can be split into four main sections:

• Feed section

• Reactor circuit section

• Separator/compression section

• Fractionation section

•

Feed Section

Feed comes from storage and passes through the Feed Filter and then followed by Feed

Coalescer. The Feed Filter removes any carry over rust & polymeric components and Feed

Coalescer and Surge drums are vessels designed to remove entrained water and provide

surge volume to even out fluctuations in feed entering the unit. Feed from the Feed Surge

Drum enters the Feed Pumps where its pressure is raised to allow the feed to enter the

reactor circuit. Feed from the Feed Pumps first preheated in the Feed/Reactor effluent

exchangers and recycle gas including make-up gas from respective compressors are

preheated in the Recycle Gas/Reactor eflluent exchangers before mixing with preheated

feed stream. The combined feed is directed to the Charge Heater where it is heated to the

reaction temperature.

Reactor Circuit Section

Combined feed from the feed section is heated to reaction temperature in the Charge

Heater. The feed/Recycle gas is then sent to the Reactors. The Reactors contain catalyst,

chosen for its ability to absorb metals in the feed and provide the proper level of

desulfurization required to meet the specified diesel product properties. Reactors have

multiple beds with intermediate quench points to control the reactor temperature. Reactor

material is cooled in the Recycle gas/ Hot Reactor Effluent Exchanger, the Feed/Reactor

Effluent Exchanger, the Stripper Feed/Effluent Exchanger, Feed/ Reactor Effluent Exchanger,

Recycle gas/Reactor Effluent Exchanger, Feed/Reactor Effluent Exchanger and then in the

separator condenser. After cooling to the appropriate temperature, reactor effluent

material is separated in the Separator. The Separator is utilized to separate the vapour and

liquid hydrocarbon phase and to decant the sour water phase. The vapour from the

separator enters the recycle gas K.O. drum from where it is compressed by the Recycle Gas

Compressor and routed to the heat exchange network and quench lines.

Separator/Compressor Section

Make-up gas is compressed from the hydrogen header to the unit operating pressure in a

Make-up Gas Compressor. Hydrocarbon liquid from the Separator is sent to the LP Flash






Drum and then routed to Stripper Feed/Bottoms Exchanger and the Stripper Feed/Reactor

Effluent Exchanger before entering the Stripper. Sour Water from the Separator is sent to

the Sour Water Stripping Unit.

Fractionation Section

The purpose of the Stripper is to remove from the diesel product, the hydrogen sulphide

and light hydrocarbons produced in the Diesel Hydrotreating Unit. An appropriate amount

of steam is added at the bottom of the Stripper to strip the hydrogen sulphide from the

liquid leaving the column bottom. Overhead vapours from the Stripper are condensed by

the water cooled Stripper Overhead Condenser and routed to the Stripper Receiver. The

Stripper Receiver separates the non-condensable vapours, hydrocarbon liquid and sour

water. The stripper overhead vapours are routed to the Sour Fuel gas Amine Absorber. Part

of the overhead liquid is refluxed back to the Stripper. Balance stripper overhead liquid is

unstablised and is sent to the Naphtha Stabilizer. Sour water from the receiver is sent to the

Sour water Stripping Unit.

Strippe bottom liquid is used to heat Stripper feed in the Stripper Feed Bottom Exchanger

and then cooled in the Air cooled Diesel Product Cooler followed by Water cooled Diesel

Product Cooler. Dissolved water present in the diesel product separates as it is cooled. The

majority of this water is removed in the Diesel Product Coalescer. The Hydrotreated diesel

product is routed to the storage.

The unstabilised naphtha from the stripper receiver after getting preheated by the

stabiliser bottoms in the stabiliser feed/bottoms exchanger is feed to the naphtha stabiliser.

The light ends and H2S leave the stabiliser from the top. The naphtha stabiliser is reboiled by

the stabiliser reboiler. The stabilised naphtha from the bottom of the stabiliser is cooled in

the stabiliser feed/ bottoms exchanger.

CATALYTIC REFORMING UNIT

Hydrotreated Naphtha feed to a Catalytic Reformer unit typically contains C6 to C10

paraffins, naphthenes and aromatics. This Hydrotreated naphtha feed has a poor octane

number and the purpose of catalytic reformer unit is to get a high octane gasoline.

Reaction section

The Hydrotreated naphtha pumped by reformer feed pumps and mixed with recycle

hydrogen gas compressed in Recycle Gas Compressor. The mixture of naphtha feed and

recycled hydrogen is preheated in reformer feed and effluent exchanger which is a vertical

true counter current (Texas Tower) exchanger. The feed naphtha and the recycled hydrogen

recovers heat in the fourth reactor effluent stream and is further heated to 498 OC in the

reformer preheater. The preheated feed enters the reformer 1st reactor which is loaded

with RG-682 catalyst. The reactions are predominantly endothermic in the first reactor and

therefore the reactor effluent is reheated in the reformer 1stinterheater. The inlet

temperature to all the four reactors is about 498 degC. The reactions in the 2nd reactor are

less endothermic but the reactor effluent still requires reheating using the interheater. The

reactions in the third reactor is much less endothermic as mostly undesired reactions like

hydrocracking reactions takes place in the reactor. The main reactions viz.






dehydrocyclization and isomerization are endothermic in nature while hydrocracking

reactions are exothermic in nature. The effluent from third reactor is heated to the required

temperature and sent to fourth reactor. The heat of fourth reactor effluent is used to

preheat the reforming feed in feed/effluent exchanger, and is then condensed in the reactor

effluent air cooler and reactor effluent cooler before being collected in the reformer

separator.

The separated vapor phase hydrogen rich gas is recycled to the compressor suction, via

reformer recycle compressor KO drum. The hydrogen rich gas is partly mixed with the

Hydrotreated naphtha and is recycled back to the reaction loop. The remaining hydrogen

rich gas from compressor discharge is distributed as hydrogen make-up gas to naphtha

pretreater unit and isomerisation unit. The remaining is sent to fuel gas network and stored

in bullets.

STABILIZATION SECTION

The separated liquid from the separator is then sent to the stabilizer column under level-

flow control cascaded to the flow control. The stabilizer feed is heated in stabilizer

feed/bottoms exchanger and introduced in the stabilizer column.

Overheads from the stabilizer are partly condensed in the stabilizer condenser and collected

in stabilizer reflux drum. The vapors from the reflux drum are routed to the fuel gas network

under pressure control. The condensed hydrocarbons are sent back to the column as reflux.

C5 reformate from stabilizer bottom is directed to the battery limit under level/flow control

after heat integration with stabilizer feed/ bottom exchanger, and finally cooling to the

desired temperature (40°C) in reformate cooler.

SULPHUR RECOVERY UNIT (SRU)

The objective of sulphur recovery unit is to recover sulphur from H2S present in acid gas

stream from Amine Regeneration Unit and sour gas from Sour Water Stripping Unit.

The process design of SRU is based on 3 stage modified Claus process. The process

consists of:

• Thermal stage (Main Combustion chamber)

• Two catalytic stages (Catalytic Converters)

• Hydrogenation Reactor with TGT unit Thermal incineration

•

98% (min.) sulphur recovery is achievable from this configuration.

Thermal Stage (main Combustion Chamber)

Acid gas from SRU is introduced via Acid gas knockout drum and sour gas from SWSU is

introduced via sour gas knockout drum. Sour water from sour gas knock out drum and

condensate from Acid gas knock out drum are collected in the condensate collection drum.

The air to the main burner is supplied by main air blowers. In order to maximize SO2 a

controlled amount of air mixed with acid gas and sour gas is fed to the burner where 1/3rd

of H2S in the feed is converted to SO2. The SO2 so formed combines with major percentage

of residual H2S to form sulphur. The hot reaction furnace effluent gases enter waste heat






boiler (WHB) where heat is recovered by producing LP steam. Sulphur produced in reaction

furnace condenses and separates in the outlet channel of the WHB and flows to sulphur pit

via sulphur seal pot. Then, the process gas is introduced into the first condenser in which it

is further cooled, sulfur vapour condenses & separates from gas & flows to sulphur pit.

Two Catalytic Stages (Catalytic Converters)

The effluent vapour ex condenser-I is reheated in Electric Reheater-I. This hot process gas

flows to Claus converter-I where additional conversion to sulphur takes place. The reaction

gas from the converter-I is cooled in sulphur condenser-II. The produced sulphur condenses

and flows to sulphur pit via sulphur seal pot. The sulphur condenser-II effluent vapour is

reheated in electric rehater-II and flows to Claus converter-II for further conversion. The

reaction gases from converter-II is cooled in sulphur condenser-III. The product sulphur

condenses and flows to sulphur pit via sulphur seal pot. The gases leaving condenser-II flow

to the Tail gas Treating unit (TGTU) where essentially all sulphur compounds will be

converted to H2S & returned to the Claus unit for further sulphur recovery. The hot gas

from the highly exothermic reaction is cooled in TGU WHB & quenched in a water quench

tower to ambient temperature. Finally, H2S is selectively absorbed in alkanolamine solution

i.e. MDEA. Vent gas from the absorber is to be incinerated before discharging to

atmosphere. Rich amine is stripped in common Amine Regenerator & H2S rich stream

recycled back to Claus section.

The sulphur drained to the pit is maintained in liquid state using pit-heating coils. During

storage of sulphur H2S dissolved in sulphur gets liberated gradually. Hence a constant

sweet air circulation is maintained over liquid sulphur using pit ejectors. Mixture of air

and stream from pit ejectors containing H2S called as sweet gas is routed to thermal

incinerator. Liquid sulphur from pit is pumped by sulphur pumps to sulphur yard where

it is solidified by spraying cold water on it.

Thermal Incineration

In the thermal incineration combustible components in the tail gas from the tail gas

coalescer and sweet gas from sulphur pit are thermally oxidized using excess of air in the

thermal incinerator. The thermal incinerator converts all the H2Sand other sulphur species

in the tail gas to sulphur dioxide.

INDMAX Unit

INDMAX employs circulating fluidized bed Riser-Reactor-Stripper configuration

similar to conventional FCC technology along with single stage full combustion

Regenerator system. The catalyst system and operating conditions employed in

INDMAX process are tailor-made and different from the conventional FCC

technology. The specially designed catalyst of the INDMAX process consists of

various synergistic components for upgradation of heavy molecules maximising

conversion with higher light olefins selectivity.

Salient Features

• Employs high riser outlet temp (ROT) of more than 540°C and high catalyst to

oil ratio (C/O) of more than 12.






• Employs proprietary catalyst system with low coke and dry gas make, higher

metal tolerance and selectivity towards light olefins.

• Excellent heat integration - Single stage full burn Regenerator; use of catalyst

cooler for feed with higher CCR (>6 wt%).

• Highly efficient hardware components

• MicroJetTM Feed injector

• Proprietary SCT riser reactor design

• High efficiency Modular Grid− stripper design

• Direct-coupled cyclone separator

• Efficient catalyst regeneration system (multi zone pipe grid distributor with

MSO nozzle)

• Advanced catalyst cooler design

Modes of Failure

There are various potential sources of large leakage, which may release hazardous

chemicals and hydrocarbon materials into the atmosphere. These could be in form of gasket

failure in flanged joints, bleeder valve left open inadvertently, an instrument tubing giving

way, pump seal failure, guillotine failure of equipment/ pipeline or any other source of

leakage. Operating experience can identify lots of these sources and their modes of failure.

A list of general equipment and pipeline failure mechanisms is as follows:

Material/Construction Defects

• Incorrect selection or supply of materials of construction

• Incorrect use of design codes

• Weld failures

• Failure of inadequate pipeline supports

Pre-Operational Failures

• Failure induced during delivery at site

• Failure induced during installation

• Pressure and temperature effects

• Overpressure

• Temperature expansion/contraction (improper stress analysis and support

design)

• Low temperature brittle fracture (if metallurgy is incorrect)

• Fatigue loading (cycling and mechanical vibration)

Corrosion Failures

• Internal corrosion (e.g. ingress of moisture)

• External corrosion

• Cladding/insulation failure (e.g. ingress of moisture)

• Cathodic protection failure, if provided

Failures due to Operational Errors

• Human error






• Failure to inspect regularly and identify any defects

External Impact Induced Failures

• Dropped objects

• Impact from transport such as construction traffic

• Vandalism

• Subsidence

• Strong winds

Failure due to Fire

• External fire impinging on pipeline or equipment

• Rapid vaporization of cold liquid in contact with hot surfaces

Hazards Associated in Refinery

Refinery complex handles a number of hazardous materials like LPG, Hydrogen, Naphtha,

Benzene, Toluene and other hydrocarbons which have a potential to cause fire and

explosion hazards. The toxic chemicals like Benzene, Ammonia, Chlorine and Hydrogen

sulfide are also being handled in the Refinery. This chapter describes in brief the hazards

associated with these materials.

Hazards Associated with Flammable Hydrocarbons

Liquefied Petroleum Gas

LPG is a colorless liquefied gas that is heavier than air and may have a foul smelling odorant

added to it. It is a flammable gas and may cause flash fire and delayed ignition. LPG is

incompatible to oxidizing and combustible materials. It is stable at normal temperatures and

pressure. If it is released at temperatures higher than the normal boiling point it can flash

significantly and would lead to high entrainment of gas phase in the liquid phase. High

entrainment of gas phase in the liquid phase can lead to jet fires. On the other hand

negligible flashing i.e. release of LPG at temperatures near boiling points would lead to

formation of pools and then pool fire. LPG releases may also lead to explosion in case of

delayed ignition.

Inhalation of LPG vapors by human beings in considerable concentration may affect the

central nervous system and lead to depression. Inhalation of extremely high concentration

of LPG may lead to death due to suffocation from lack of oxygen. Contact with LPG may

cause frostbite.






Refer Table below for properties of LPG.

S.No Properties (LPG) Values

1 LFL (% v/v) 1.7

2 UFL (% v/v) 9.0

3 Auto ignition temperature (°C) 420-540

4 Heat of combustion (Kcal/Kg) 10960

5 Normal Boiling point (°C) -20 to -27

6 Flash point (°C) -60






Hydrogen

Hydrogen (H2) is a gas lighter than air at normal temperature and pressure. It is highly

flammable and explosive. It has the widest range of flammable concentrations in air among

all common gaseous fuels. This flammable range of Hydrogen varies from 4% by volume

(lower flammable limit) to 75% by volume (upper flammable limit). Hydrogen flame (or fire)

is nearly invisible even though the flame temperature is higher than that of hydrocarbon

fires and hence poses greater hazards to persons in the vicinity. Constant exposure of

certain types of ferritic steels to hydrogen results in the embrittlement of the metals.

Leakage can be caused by such embrittlement in pipes, welds, and metal gaskets.

In terms of toxicity, hydrogen is a simple asphyxiant. Exposure to high concentrations may

exclude an adequate supply of oxygen to the lungs. No significant effect to human through

dermal absorption and ingestion is reported. Refer to Table 8 for properties of hydrogen.

S.No Properties (H2) Values

1 LFL (% v/v) 4.12

2 UFL (% v/v) 74.2

3 Auto igniton temperature (°C) 500


5 Normal Boiling point (°C) -252

6 Flash point (°C) NA

Naphtha and Other Heavier Hydrocarbon

The major hazards from these types of hydrocarbons are fire and radiation. Any spillage or

loss of containment of heavier hydrocarbons may create a highly flammable pool of liquid

around the source of release.

If it is released at temperatures higher than the normal boiling point it can flash significantly

and would lead to high entrainment of gas phase in the liquid phase. High entrainment of

gas phase in the liquid phase can lead to jet fires. On the other hand negligible flashing i.e.

release at temperatures near boiling points would lead to formation of pools and then pool

fire. Spillage of comparatively lighter hydrocarbons like Naphtha may result in formation of

vapor cloud. Flash fire/ explosion can occur in case of ignition. Refer to Table below for

properties of Naphtha.

S.No Properties (Naptha/other HCs) Values

1 LFL (% v/v) 0.8

2 UFL (% v/v) 5.0

3 Auto ignition temperature (°C) 228


5 Normal Boiling point (°C) 130 -155

6 Flash point (°C) 38-42






Hazard Associated with Toxic/Carcinogenic materials

Hydrogen Sulfide

Hydrogen sulfide is a known toxic gas and has harmful physiological effects. Accidental

release of hydrocarbons containing hydrogen sulfide poses toxic hazards to exposed

population. Refer Table below for hazardous properties of Hydrogen Sulfide.

S.No Threshold Limits (H2S) Concentration

(ppm)

1 Odour threshold 0.0047

2 Threshold Limit Value (TLV) 10 10

3 Short Term Exposure Limit

STEL (15 minutes)

15

4 Immediately Dangerous to life

and Health (IDLH) level (for 30

minutes exposure)

100

Chlorine

Chlorine is required in a refinery complex for water treatment. Chlorine tonner is therefore

located near the Cooling water system. Chlorine gas is not flammable but highly poisonous

in nature. Its routes of entry into the human body are through inhalation, ingestion, skin and

eyes. An exposure to chlorine can cause eye irritation, sneezing, restlessness. Exposure to

high concentration of chlorine can cause respiratory distress and violent coughing. Lethal

effects of inhalation depend not only on the concentration of the gas to which people are

exposed, but also on the duration of exposure. The toxic effects of chlorine are listed in

Table below:

S.No Properties (Cl) Values

1 Short Term Exposure Limit STEL

(15 minutes)

2



minutes exposure)

10

Ammonia

Ammonia may be release from failure of connection tube of ammonia cylinder used in

Atmospheric unit (AU). Ammonia is also likely to be present in sour gas produced from Sour

water stripper unit (SWSU). The hazard associated with ammonia is both toxic and

flammable hazards. Toxic hazards being more pronounced. Vapors of ammonia may cause

severe eye or throat irritation and permanent injury may result. Contact with the liquid

freezes skin and produces a caustic burn. Table below indicates the toxic properties of

ammonia.






S.No Properties (NH3) Values

1 Threshold Limit Value (TLV) 10 25

2 Short Term Exposure Limit STEL

(15 minutes)

35



minutes exposure)

300

Characterising of failures:

Hazards from Petroleum Products Storage and Handling

Accidental release of flammable or toxic vapors can result in severe consequences. Delayed

ignition of flammable vapors can result in blast overpressures covering large areas. This may

lead to extensive loss of life and property. Toxic clouds may cover yet larger distances due

to the lower threshold values in relation to those in case of explosive clouds (the lower

explosive limits). In contrast, fires have localized consequences. Fires can be put out or

contained in most cases; there are few mitigating actions one can take once a vapor cloud is

released.

In a petroleum marketing installation such as the plant in question, the main hazard arises

due to the possibility of leakage of petroleum products during decanting (number of hose

connections, tank lorry movement etc.), storage, filling and transportation. To formulate a

structured approach to identification of hazards an understanding of contributory factors is

essential

Operating Parameters

Inventory

Inventory Analysis is commonly used in understanding the relative hazards and short listing

of release scenarios. Inventory plays an important role in regard to the potential hazard.

Larger the inventory of a vessel or a system, larger the quantity of potential release. A

practice commonly used to generate an incident list is to consider potential leaks and major

releases from fractures of pipelines and vessels containing sizable inventories. Each section

is then characterized by the following parameters required for consequence modeling:

• Mass of flammable material in the process/storage section (oil/gas)

• Pressure, Temperature and composition of the material

• Hole size for release

Loss of Containment

Plant inventory can get discharged to Environment due to Loss of Containment. Various

causes and modes for such an eventuality have been described. Certain features of

materials to be handled at the plant need to the clearly understood to firstly list out all

significant release cases and then to short list release scenarios for a detailed examination.






Liquid Outflow from a vessel/ line

Liquid release can be either instantaneous or continuous. Failure of a vessel leading to an

instantaneous outflow assumes the sudden appearance of such a major crack that

practically all of the contents above the crack shall be released in a very short time. The flow

rate will depend on the size of the hole as well as on the pressure in front of the hole, prior

to the accident. Such pressure is basically dependent on the pressure in the vessel.

Vaporization

The vaporization of released liquid depends on the vapor pressure and weather conditions.

Such consideration and others have been kept in mind both during the initial listing as well

as during the short listing procedure. Initial listing of all significant inventories in the process

plants was carried out. This ensured no emission through inadvertence.

Based on the methodology discussed above a set of appropriate scenarios was generated to

carryout Risk Analysis calculations for Pool fire, fire ball, source strength, toxic threat zone,

flammability threat zone, overpressure (blast force) from vapor cloud explosion.

Consequence Analysis

Consequence analysis involves the application of the mathematical, analytical and computer

models for calculation of the effects and damages subsequent to a hydrocarbon / toxic

release accident. Computer models are used to predict the physical behavior of hazardous

incidents. The model uses below mentioned techniques to assess the consequences of

identified scenarios:

• Modeling of discharge rates when holes develop in process equipment/pipe work.

• Modeling of the size & shape of the flammable/toxic gas clouds from releases in the

atmosphere.

• Modeling of the flame and radiation field of the releases that are ignited and burn as

jet fire, pool fire and flash fire.

• Modeling of the explosion fields of releases which are ignited away from the point of

release.

•

The different consequences (Flash fire, pool fire, jet fire and Explosion effects) of loss of

containment accidents depend on the sequence of events & properties of material released

leading to the either toxic vapor dispersion, fire or explosion or both.

Consequence Analysis Modeling

Discharge Rate

The initial rate of release through a leak depends mainly on the pressure inside the

equipment, size of the hole and phase of the release (liquid, gas or two-phase). The release

rate decreases with time as the equipment depressurizes. This reduction depends mainly on

the inventory and the action taken to isolate the leak and blow-down the equipment.






Dispersion

Releases of gas into the open air form clouds whose dispersion is governed by the wind, by

turbulence around the site, the density of the gas and initial momentum of the release. In

case of flammable materials the sizes of these gas clouds above their Lower Flammable

Limit (LFL) are important in determining whether the release will ignite. In this study, the

results of dispersion modeling for flammable materials are presented LFL quantity.

Flash Fire

A flash fire occurs when a cloud of vapors/gas burns without generating any significant

overpressure. The cloud is typically ignited on its edge, remote from- the leak source. The

combustion zone moves through the cloud away from the ignition point. The duration of the

flash fire is relatively short but it may stabilize as a continuous jet fire from the leak source.

For flash fires, an approximate estimate for the extent of the total effect zone is the area

over which the cloud is above the LFL.

Jet Fire

Jet fires are burning jets of gas or atomized liquid whose shape is dominated by the

momentum of the release. The jet flame stabilizes on or close to the point of release and

continues until the release is stopped. Jet fire can be realized, if the leakage is immediately

ignited. The effect of jet flame impingement is severe as it may cut through equipment,

pipeline or structure. The damage effect of thermal radiation is depended on both the level

of thermal radiation and duration of exposure.

Pool Fire

A cylindrical shape of the pool fire is presumed. Pool-fire calculations are then carried out as

part of an accidental scenario, e.g. in case a hydrocarbon liquid leak from a vessel leads to

the formation of an ignitable liquid pool. First no ignition is assumed, and pool evaporation

and dispersion calculations are being carried out. Subsequently late pool fires (ignition

following spreading of liquid pool) are considered. If the release is bounded, the diameter is

given by the size of the bund. If there is no bund, then the diameter is that which

corresponds with a minimum pool thickness, set by the type of surface on which the pool is

spreading.

While modeling cases of lighter hydrocarbons in the range of naphtha and MS wherein the

rainout fraction have been minimal (not leading to pool formation) due to the horizontal

direction of release, downward impingement has been considered for studying the effects

of pool fire for consequence analysis only. Pool fires occur when spilled hydrocarbons burn

in the form of large diffusion flames. Calculating the incident flux to an observer involves

four steps, namely

• Characterizing the flame geometry

• Estimation of the flame radiation properties

• Computation of the geometric view factors






• Estimation of flame attenuation coefficients and computation of geometric view

factors between observer and flame.

The size of the flame will depend upon the spill surface and the thermo chemical properties

of the spilled liquid. In particular, the diameter of the fire, the visible height of the flame,

the tilt and drag of the flame etc. The radioactive output of the flame will depend upon the

fire size, the extent of mixing with air and the flame temperature. Some fraction of the

thermal radiation is absorbed by the carbon dioxide and water vapor in the intervening

atmosphere. In addition, large hydrocarbon fires produce thick smoke which significantly

obscure flame radiation

The calculations for radiation damage distances start with estimation of the burning

velocity:

Y= 92.6 e – 0.0043TbMw10-7/(x 6)

Where y= burning velocity in m/s

Mw= molecular weight in kg/kg mol

Tb= normal boiling point

The next step involves calculation of the equivalent diameter for the spreading pool- this

depends upon the duration of the spill (continuous, instantaneous, finite duration etc.). This

is calculated using expressions like:

Deq. =2(V/3.142y)1/2

Where Deq. Is the steady state diameter of the pool in m

V= liquid spill rate in m3/s

Y= Liquid burning rate in m/s

In the absence of frictional resistance during spreading, the equilibrium diameter is reached

over a time given by:

Teq.= 0.949 Deq./(∆y X Deq.)1/3

The visible flame height is given by;

Hflame= 42Dp ((BvD/Da(gDp)1/2)0.61

Where Hflame = flame height in m

D= density in kg/m3

Da= air density in kg/m3

g = gravitational acceleration or 9.81 m/s2

The emissive power of a large turbulent fire is a function of the black body emissive power

and the flame emissivity. The black body emissive power can be computed by Planck’s law

of radiation. The general equation used for the calculation is:

EP= -0.313Tb+117

Where Ep is the effective emissive power in kw/m2

Tb= normal boiling point of the liquid in °F

Materials with a boiling point above 30 °F typically burn with sooty flames-the emissive

power from the sooty section is about 20 kW /m2. The incident flux at any given location is

given by the equation:






Qincident = EP * t * V F

Where Qincident = incident flux in kw/m2

t= transmitivity (a function of path length, relative humidity and flame temperature) often

taken as 1 and the attenuation of thermal flux due to atmospheric absorption ignored.

VF= geometric view factor

The view factor defines the fraction of the flame that is seen by a given observer.

V F= 1.143 (Rp/X) 1.757

Where X= distance from the flame centre in m

Rp= pool radius in m

Based on the radiation received, the fatality levels are calculated from Probit equation,

which for protected clothing is given by:

Pr.= -37.23 + 2.56 ln (t X Q4/3)

Where Pr. = Probit No.

t= time in seconds

Q heat radiation in w/m2

Blast Overpressures

Blast Overpressures depend upon the reactivity class of material and the amount of gas

between two explosive limits. MS could give rise to a VCE due to their vapor pressures -

however, as the results will indicate, the cloud flammable masses are quite small due to the

high boiling point and low vapor pressures. In addition, unless there is sufficient extent of

confinement, it is unlikely to result in any major explosion. Examples where flammable

mixtures could be found are within storage tanks and road tankers. Open-air explosions are

unlikely. As a result, damage would be limited Equations governing the formation of

overpressures in an explosion are given later. Blast overpressures are calculated based on

comparison of combustion energy per unit mass of a vapour cloud with that of TNT and

taking into account that only a fraction of the energy will contribute to the explosion.

Overpressure data compiled from measurements on TNT are used to relate overpressure

data to distance from explosions. The equivalent mass of TNT is calculated using the

equations:

MTNT= (Mcloud X (∆Hc.)/1155 X Yf)

Where MTNT is the TNT equivalent mass (lb)

∆Hc = Heat of combustion is in Kcals/kg

Mcloud is mass in cloud in lbs

Yf is the yield factor

The distance to a given overpressure is calculated from the general equation:

X=MTNT 1/3 exp (3.5031-0.7241 ln (Op) + 0.0398 (ln Op))2

Where X is the distance to a given overpressure in feet Op is the peak overpressure

Toxic Realease in Air:






The aim of the toxic risk study is to determine whether the operators in the plant, people

occupied buildings and the public are likely to be affected by toxic substances. Toxic gas

cloud e.g. H2S, chlorine, etc was undertaken to the Immediately Dangerous to Life and

Health concentration (IDLH) limit to determine the extent of the toxic hazard created as the

result of loss of containment of a toxic substance.






Size and duration of release

Leak size considered for selected failure cases are as listed below:

S.No Failure Description Leak Size

1 Pump Seal Failure 6 mm hole size

2 Flange gasket failure 10 mm hole size

3 Instrument tapping failure 19 mm hole size

4 Small hole 20 mm hole size

5 Large hole 50 mm hole size

6 Catastrophic failure Complete rupture of

pressure vessel

The duration of release is a very important input to the consequence analysis as this directly

dictates the quantity of material released. General basis for deciding the duration of release

is given in the Table below-

S.No Blocking System Configuration Isolation

Time (M)

1 Fully automatic blocking system( including automatic detection

and closure of block valves) 2

2

For remote operated blocking systems (detection is automatic,

but control room operator must validate alarm signal and close

block valve remotely)

10

3

For hand-operated blocking systems (detection is automatic,

but control room operator must validate alarm, go to field and

manually close block valve)

30

Damage Criteria

In order to appreciate the damage effect produced by various scenarios,

physiological/physical effects of the blast wave, thermal radiation or toxic vapor exposition

are discussed.

LFL or Flash Fire

Hydrocarbon vapor released accidentally will spread out in the direction of wind. If a source

of ignition finds an ignition source before being dispersed below lower flammability limit

(LFL), a flash fire is likely to occur and the flame will travel back to the source of leak. Any

person caught in the flash fire is likely to suffer fatal burn injury. Therefore, in consequence

analysis, the distance of LFL value is usually taken to indicate the area, which may be

affected by the flash fire.

Flash fire (LFL) events are considered to cause direct harm to the population present within

the flammability range of the cloud. Fire escalation from flash fire such that process or

storage equipment or building may be affected is considered unlikely.






Thermal Hazard Due to Pool Fire, Jet Fire

Thermal radiation due to pool fire, jet fire or fire ball may cause various degree of burn on

human body and process equipment. The following table details the damage caused by

various thermal radiation intensity.

S.No Incident Radiation

(kW/m2)

Type of Damage

1 0.7 Equivalent to Solar Radiation

2 1.6 No discomfort for long exposure

3 4.0 Sufficient to cause pain within 20 sec. Blistering of

skin (first degree burns are likely)

4 9.5 Pain threshold reached after 8 sec. Second degree

burns after 20 sec.

5 12.5 Minimum energy required for piloted ignition of

wood, melting plastic tubing etc.

6 25 Minimum energy required to ignite wood at

indefinitely long exposure

7 37.5 Sufficient to cause damage to process equipment

Vapour Cloud

In the event of explosion taking place within the plant, the resultant blast wave will have

damaging effects on equipment, structures, building and piping falling within the

overpressure distances of the blast. Tanks, buildings, structures etc. can only tolerate low

level of overpressure. Human body, by comparison, can withstand higher overpressure. But

injury or fatality can be inflicted by collapse of building of structures.

The following table illustrates the damage effect of blast overpressure.

S.No Peak Overpressure Damage Type

1 12.04 psi Total Damage

2 4.35 psi Heavy Damage

3 1.45 psi Moderate Damage

4 0.44 psi Significant Damage

5 0.15 psi Minor Damage

Risk Assessment of INDMAX:

In order to achieve the objective of rapid risk analysis study, following activities are carried

out:

• Identification of all probable major accident cases.

• Analysis of consequences of the above to find out various hazard distances and

impact zones.

• Suggest mitigating measures to eliminate/reduce above hazards









The first step in risk assessment is identification of hazards. Hazard is defined as a physical

or chemical condition with the potential of accident which can cause damage to people,

property or the environment. Hazards are identified by careful review of plant operation

and nature of materials used. The various scenarios by which an accident can occur are then

determined, concurrently study of both probability and the consequences of an accident is

carried out and finally risk assessment is made. If this risk is acceptable then the study is

complete. If the risk is unacceptable then the system must be modified and the procedure is

restarted.

Individual risks are the key measure of risk acceptability for this type of study, where it is

proposed that:

• Risks to the public can be considered to be broadly acceptable (or negligible) if below

10-6 per year (one in 1 million years). Although risks of up to 10-4 per year (1 in

10,000 years) may be considered acceptable if shown to be As Low As Reasonably

Practicable (ALARP), it is recommended that 10-5 per year (1 in 100,000 years) is

adopted for this study as the maximum tolerable criterion.

• Risks to workers can be considered to be broadly acceptable (or negligible) if below

10-5 per year and where risks of up to 10-3 per year (1 in 1000 years) may be

considered acceptable if ALARP.

The highest LSIR (location specific individual risk) location at INDMAX unit is 1E-05 per year.

The maximum LSIR in the units are listed below:

S.No Unit Maximum LSIR

1 HDT/HGU field operator

room

6.57 E-08

2 SRU block field operator

room

2.31 E-08

3 INDMAX field operator

room

1.14 E-07

Individual Risk to worker at INDMAX Unit (ISIR):

The location specific individual risk (LSIR) is risk to a person who is standing at that point 365

days a year and 24 hours a day. The personnel in INDMAX unit are expected to work 8 hour

shift as well as general shift. The actual risk to a person i.e. “Individual Specific Individual

Risk” would be far less after accounting for the time fraction a person is expected to spend

at a location

ISIR Area = LSIR x (8/24) (8 hours shift) x (Time spent by and individual/8 hours)

The maximum ISIR in the units are listed below:

S.No Unit Maximum LSIR

1 HDT/HGU field operator

room

2.19 E-08






2 SRU block field operator

room

7.7 E-09

3 INDMAX field operator

room

3.8 E-08

Societal Risk are also proposed, although these should be used as guidance only. A criterion

of 10-4per year is recommended for determining design against the fire and explosion loads

that occur with a frequency of 1 in 10,000 years. The societal risk parameters for INDMAX

unit is shown in figure below in the form of FN curve. The result from the FN curve show

that the societal risk due to INDMAX Unit is below the ALARP region which is broadly

acceptable or negligible risk.

Figure: FN curve for societal risk at INDMAX unit at BONGAIGAON REFINERY PLANT






The significant risk contributions from INDMAX unit is based on result available from PHAST

show below:

Top Risk Contributors at INDMAX unit:

S.No Scenario Societal risk contribution

1 Rupture in the inlet line to stabilizer /debutanizer 52.09

2 Rupture from shell side of Stripper feed exchanger 22.34

3 Leak from shell side of Stripper feed exchanger 11.72

4 Rupture in line to main fractionator column 2.22

5 Leak in discharge line of LPG R/D Pump 1.01

Disaster management

Disaster Scenarios

Based on the Risk Analysis done for BONGAIGAON REFINERY PLANT and various scenarios of

industrial accidents in the refining sector, following scenarios have been identified for

finalising detailed action plan for Off-Site Emergency situation.

1. Fire in storage tanks & tank farm area (major fire) in sru, due to gasket failure.

2. Fires and explosions in the unit area

3. Boiler explosion in captive power plant

4. Un-confined vapour cloud explosion (LPG)

5. Profuse naphtha leak in cooling water system

6. Large oil spillage flowing out of the refinery

7. Chlorine gas leak from cylinder (s)

8. Lpg cylinders explosions in LPG bottling plant (Bongaigaon Refinery Plant)

9. H2s leakage from acid gas knock out drum top line

In addition to the above, any emergency, which goes beyond the control of BONGAIGAON

REFINERY PLANT and may affect the outside population, will be considered as off-site

disaster.

CLASSIFICATION OF EMERGENCIES

(1) Emergencies can be categorized into three broad levels on the basis of seriousness and

response requirements;






(a) Level 1 : This is an emergency or an incident which

i. Can be effectively and safely managed, and contained within the site, location or

installation by the available resources

ii. Has no impact outside the site, location or installation

iii. Is unlikely to be danger to life, the environment or to company assets or reputation

(b) Level 2: This is an emergency or an incident which

i. Cannot be effectively and safely managed or contained at the site, location or

installation by available resource and additional support is required

ii. Is having, or has the potential to have an effect beyond the site, location or

installation and where external support of mutual aid partner may be involved

iii. Is likely to be danger to life, to the environment, to company assets or

reputation

(c) Level 3: This is an emergency or an incident which

i. Is catastrophic and is likely to affect the population, property and environment inside

and outside the installation, and management & control is done by District

Administration. Although the level-III emergency falls under the purview of District

Authority but till they step in, it shall be responsibility of the unit to manage the

emergency.

Note: Level-I & Level-II shall normally be grouped as onsite emergency and Level-III as off-

site emergency. Off-site Disaster Management Plan will be activated in case of Level 3

emergency situation

Types of Disaster: •

• Fire & Explosion in Tank Farm Area.

• Major Fire/Explosion in Unit Area.

• Accidental release of Toxic Gas in to atmosphere

• Large Oil Spillage which can escape from the Complex.

• Vapour Cloud Explosion/BLEVE •

Causes of Disaster

S.No Man made Natural Extraneous

1 Heavy leakage Flood Riots/Civil disorder/

2 Fire Earthquake Mob attack/ Terrorism

3 Explosion Cyclone Bomb Threat

4 Failure of Critical

Control system

Breakout of disease War hit by missiles

5 Design deficiency Excessive rains Abduction

6 Unsafe acts Food water poisoning

7 In-adequate

maintenance






Off -site Disaster Management Plan

The Deputy Commissioner (DC), Chirang District will be the Chief District Emergency

Coordinator (CDEC) for operating the Off-Site Disaster Management Plan. Additional Deputy

Commissioner (ADC) will be Dy. Chief District Emergency Coordinator (DCDEC). The CDEC

will be the overall in charge of all off-site emergency activities. He will coordinate various

activities in co-ordination with the onsite Chief Incident Controller (CIC), BONGAIGAON

REFINERY PLANT. CDEC will also be the authority to order evacuation wherever necessary.

He will co-ordinate with various service agencies such as Police, Fire Brigade, Medical,

Transport, Railways, Civil Defence, Army (as and when required), Factory Inspectorate,

Pollution Control Board etc.

NOTIFICATION OF DISASTER AND ALL CLEAR SIGNAL (NORMALCY)

The CDEC will make an assessment of the nature of the incident and its potential impact

on life, property or the environment and declare a DISASTER if required by –

• Public announcement over mobile PA system.

• Using the air raid siren system of the civil defence Organisation.

• Using Sirens of Railways, BONGAIGAON REFINERY PLANT or other industries.






The CDEC will declare a "Return-to Normal"/All clear, after ensuring that cause of

disaster and its effects are over.

SIREN CODE OF BONGAIGAON REFINERY PLANT

Siren code will be as follows:

1. SMALL FIRE: No siren

2. MAJOR FIRE: A wailing siren for two minutes (30 sec.+ gap 15 sec +30sec +gap 15 sec

+30 sec)

3. DISASTER: Same type of siren as in case of Major Fire but the same will be sounded

for three times at the interval of one minute i.e.( wailing siren 2 min + gap 1 min +

wailing siren 2 min + gap 1min + wailing siren 2 min) total duration of Disaster siren to

be eight minutes.

4. ALL CLEAR (For fire): Straight run siren for two minutes.

5. TEST: Straight run siren for 30 seconds at 12 noon and 12.45 PM every day.

RESPONSIBILITIES OF CDEC/DCDEC

1. Establishing the Crisis control Room near BONGAIGAON REFINERY PLANT premises at any

of the following locations.

• DC Office, Chirang PH: 241992

• Police Station, Dhaligaon PH: 241262

• Guest House, BONGAIGAON REFINERY PLANT (Deoshri) PH: 4585

• Disaster Control Centre BONGAIGAON REFINERY PLANT PH: 241345 / 3336 / 3337

• Any other place so decided by CDEC.

• A Crisis Control Room will be established in the Conference Hall of DC’s Office which

will work 24 hours a day and throughout the year.

2. Establishing communication linkage at the control room.

3. Requisition fire fighting services from Bongaigaon and NF Railways, if the situation

demands.

4. Coordinate the rescue operation with police.

5. Arrangement for announcement through PA system to the affected population around,

action to be taken by them and advising for evacuation, if required.

6. Identify places of safe shelters where the evacuated population has to belodged and

arrange tents etc. for shelters in open area/Public hall/Schools.

7. Requisitioning all possible modes of transport for shifting them to predetermined shelters

if required.

8. Ensure supply of food, drinking water and proper sanitation to the evacuated persons

kept in various shelter locations.

9. Organise necessary medical aid through district health authorities and other voluntary

institutions.

10. Arrange for protection of property of the evacuated persons during their absence.

11. Monitoring the shelter camps and the evacuated localities till the normalcy is restored.

12. Making public announcements from time to time in the shelter camps and in the

neighbouring city areas and coordinating media persons.






13. Transportation of the evacuated persons back to their localities after the emergency has

been controlled.

7.5.7 ESTABLISHING OF CENTRAL CRISIS CONTROL ROOM (CCR)

The CDEC/DCDEC will coordinate the activities from the CCR identified already for the

purpose near the refinery premises. It is desirable to have 2 CCRs so that if one is

affected by the incident, then the other one is available for use.

COMMUNICATION SYSTEM

The following communication system should be available connecting the CCR with the

refinery and emergency services:

* Telephone

* Wireless Communication System

* Portable Public Addressing System

CHECKLIST OF ITEMS IN CCR

Following items shall be provisioned for in the CCRs. The agency / authority responsible for

provisioning is also indicated below:

a. Checklist of actions to be taken by CIC BONGAIGAON REFINERY PLANT –

By CIC, BONGAIGAON REFINERY PLANT

b. A complete list of areas showing population densities to plan for people to be

evacuated, if required and pick-up points for evacuation. –

By CDEC

c. A copy of Off-Site Disaster Management Plan-


d. Emergency power supply and lights-


e. Personal Protective Equipments such as Self Contained Breathing Apparatus, dust

filters, PVC suits/hand gloves, Safety Goggles, helmets, gum boots etc.-


f. Latest/updated list of resources available to mitigate the emergency:

By CIC, BONGAIGAON REFINERY PLANT for resource at BONGAIGAON

REFINERY PLANT and ADC for other resources in the district.

g. Adequate manpower equipped with various emergency services/facilities as and

when needed on demand. :

By CDEC

h. List of organisations and specialists available to handle the emergency as contained

in the Offsite DMP

i. A copy of Map/plot plan of Chirang/Bongaigaon District. –

By CDEC

j. Latest/updated BSNL Telephone Directory: -

By CDEC

RESPONSIBILITIES OF ON-SITE CHIEF INCIDENT CONTROLLER (CIC) BONGAIGAON REFINERY

PLANT






On-site Chief Incident Controller is the overall in-charge of all activities at the site of the

incident inside the BONGAIGAON REFINERY PLANT. He will act according to the on-site

emergency plan. He is also responsible to inform CDEC in case of a major emergency

/disaster at BONGAIGAON REFINERY PLANT which is likely to have effect outside of the

complex. He shall:

a. Provide full details to CDEC about the nature and magnitude of the emergency and the

area likely to be effected.

b. Coordinate internal functions of BONGAIGAON REFINERY PLANT

c. Organise technical back up to the CDEC

d. Advise CDEC for evacuation. Also to suggest location for rehabilitation, if pertinent.

e. Alert CDEC in case of contamination in effluent.

f. Provide administrative and hardware support to the Disaster Crisis Control Room.eg.

Blow off all clear siren on the advice of CDEC.

On Site Disaster Organisation

Chief Incident Controller (BONGAIGAON REFINERY PLANT)

Name & Authority Hou

se

No.

Tel

(O)

Tel

(R)

Mobile

Mr.R.K.Sharma,GM(PJ) Bungaow-

5

241338 241226 9435499800

Mr. G.C.Sikder, GM(T) Bungalow-

2

241206 243318 9435139681

Mr. A Kalita, GM(TS&HSE) D-154 241334 241392 9435482605

Nodal Officer

Name & Authority Bungalow

no.

Tel (O) Tel (R) Mobile

Executive Director

BONGAIGAON

REFINERY

1 241030 241241 9435120814

Conclusions and Recommendations:

A rapid risk analysis study for the proposed CDU, CRU-MSQ unit, DHDT, INDMAX SDS units

of BONGAIGAON REFINERY PLANT, at Bongaigaon was carried out to evaluate consequence

due to identified potential failure scenarios. Based on the results and discussions, the

principal conclusions and recommendations are detailed below. The relevant sections of

the report should be referred to for further details.






For DHDT:

1. At the offsites, tanks are provided for storage of HGU feed, Diesel and Coker Kero

product. In the event of tank on fire the thermal hazard distance for 8kw/m2 was

estimated to be about 16m, 17m and 17m respectively and observed to be restricted

to the respective tank area. The hazard distances due to 32Kw/m2 are not realised. It

can therefore be stated that the inter tank distances are adequate and fire-fighting

facilities should be provided as per the applicable standards. Also, the standard

operation practices to include the mode of dyke valve operation to OWS or to storm

sewer.

2. For CPP expansion day tanks for HSD, LSHS & Naphtha shall be provided for fuel supply.

Therefore, an event of “tank fire” cases for HSD and Naphtha day tanks were

considered to estimate the thermal hazard to facilities in the vicinity. It was estimated

that at tank level 32 kW/m2 radiation hazard distances extend to about 5m and 6m,

respectively for 1F weather conditions and are restricted to the tank periphery. The

8kW/m2 radiation hazard distance estimated to be 13m in case of HSD tanks would

affect the adjacent LSHS tank. It is also observed that at ground level, the thermal

radiation hazard zone due to HSD tank fire extends to a distance of 12m for 8 kW/m2

radiation intensity.

It is recommended to increase the inter tank distances such that the adjacent tanks are

outside the 8 kW/m2 radiation hazard zone or the tanks are to be provided with

cooling facilities. Alternatively, since these fuel day tanks are low height and low

capacity tanks, vessels for storage of the fuel instead of tanks should be considered.

3. In the DHDT area the LFL plume due to HP Separator bottom line failure is likely to

envelop HGU, cooling tower, substation, OWS sump & pump house and partially affect

the existing control room, nitrogen block, ecopark, CPP and the control room. It is

therefore, recommended to consider provision of adequate measures such as facility

for remote isolation of the separator and installing HC detectors at strategic locations

in the unit for early detection of leakage and prevention of major releases.

4. In the DHDT area catastrophic failure of stabilizer reflux drum is considered. It is

estimated that the 5-psi and 2-psi blast wave overpressure distance would extend

to84m and 106m, respectively at 1F weather condition. The 2-psi blast overpressure

effect zone is likely to affect partially the HGU block, substation, pipe sleepers and the

nearby road while 5-psi blast wave may approach these areas.

Due to presence of H2S in the stabilizer reflux drum feed toxic hazards are also evaluated

due to catastrophic failure of stabilizer. Accordingly, toxic hazard distances for IDLH

(100 ppm) concentration were estimated to be about 108m for 1F weather conditions

and observed to envelope the DHDT block and extends to substation, HGU area and

nearby roads. While, the 1%, 5% and 50% fatality affect zone lie within the DHDT

battery limit. It is however, recommended to consider installation of hydrocarbon/H2S

detectors at strategic location in the process unit.






5. In the HGU a large hole in tubular reformer outlet line is considered. In the event of

immediate ignition of the released material a jet flame may result. The jet flame is

likelyto damage any equipment coming in its path and may lead to domino effects. It

is recommended to provide hydrocarbon/hydrogen detectors in appropriate location

inside the unit.

6. In the SRU failure scenario of accidental release of H2S due to Acid Gas KOD top line

flange gasket failure is considered. In the ARU a failure scenario of Amine regenerator

reflux drum top line flange gasket failure is considered. The toxic hazard distances for

IDLH (100 ppm) concentration and concentration causing 1%, 5% and 50% fatality are

estimated. It is observed that at 1F weather conditions the H2S cloud at IDLH

Concentration would envelope the control room near the SRU block.

It is therefore, recommended to provide adequate number of H2S detectors inappropriate

location of the plant and at the control room air handling intake to warn the

operators/supervisors for initiating shut down of air handling unit of control room.

Control room should be air pressurised to prevent the infiltration of the

flammable/toxic gas incase of accidental release. Air sucked for pressurisation should

be from a safe location. Breather apparatus in healthy condition should be readily

available in case of detection of accidental release of H2S for escape/isolation of the

leak source.

In case of acid gas KOD flange gasket failure it is observed that the IDLH cloud would travel

about 180m beyond the plant boundary therefore it suggested that any human

settlements within 200m of the plant boundary near the sulphur block should be

avoided.

7. In the naphtha pre-treatment unit, two failure scenarios viz. naphtha feed pump

mechanical seal failure and sulphur guard bottom line flange gasket failure are

considered. It is estimated that flash fire distances would extend to 11 m and 25 m

respectively and are restricted within the unit battery limit. The thermal hazard zone

due to 12.5 kW/m2 radiation intensity extends to about 13m and 15m respectively,

and approach the adjacent hot oil area and fractionation section area. It is therefore

recommended to provide hydrocarbon detectors at strategic location near the unit.

8. In the CRU events of reformer feed pump mechanical seal failure and reformer recycle

gas compressor discharge line flange gasket failure have been considered. The flash

fire distances are estimated to be about 29 m and 6 m for 1F weather condition. The

thermal hazard zone due to 12.5 kW/m2 radiation intensity extends to 14m and 17m

for 1F weather condition and are mostly restricted to the unit battery limit. However

in case offeed pump mechanical seal failure the thermal hazard zone due to

12.5kw/m2 radiations may approach the compressor area. It is recommended the

pump should be located such that compressor area is outside the thermal hazard zone

of 12.5kw/m2.






9. Thermal radiation hazard from pool fire due to seal leakage of the pumps handling light

hydrocarbons (stripper overhead pump) is likely to affect the adjacent equipment. It is

recommended to consider double mechanical seal pumps and also installation of

hydrocarbon detectors near the pump seals along with appropriate deluge systems as

per OISD guidelines.

10. Fired heaters are the potential ignition source in the process plant. Released gases due

to failure of seal of pumps handling light hydrocarbon/failure of compressor

gland/gasket leak is likely to be ignited in presence of ignition source. It is

recommended that the location of heaters should be in upwind direction in order to

reduce the ignition probability of the released gas.

11. Periodic health check and maintenance of all equipment and plant piping are required to

be ensured. Periodic calibration and testing of alarms, trips, and interlocks should be

given attention. It is also suggested to use minimum number of joints with proper

gasket for all joints. Gaskets should be replaced by new ones everytime the flange

joints are opened.

For INDMAX:

Although the results of this Risk analysis show that the risks to the public are broadly

acceptable (or negligible), they will be sensitive to the specific design and/or modelling

assumptions used. The maximum risk to persons working in the INDMAX unit is 3.8x10-8 per

year which is below the unacceptable level and is in the lower part of ALARP triangle. It is

observed that the iso-risk contour of 1x10-5 per year is within the INDMAX unit and the risk

contour of 1x10-6 per year extended to the adjoining facilities on South East direction which

have storage tankage and SRU unit.

The high risk contributors in the INDMAX unit are Stabilizer/Debutanizer stripper Feed

exchanger. The major conclusions and recommendations based on the risk analysis of the

identified representative failure scenarios are summarized below:

• The individual risk from all scenarios is found below the ALARP region for

Employee and Public for INDMAX unit.

• The INDMAX unit of refinery is covered in the process safety management system

of refinery.

• Mitigate the risk by preventing toxic cloud travelling beyond the plant boundary in

South West side but the concentration of Hydrocarbons beyond the boundary is

very low, therefore no specific mitigation measures are required for that point.

• Gas detectors are provided at critical locations. Operators are well trained about

the fire and gas detection systems.

• Emergency stop of critical equipment’s are available in control room.

• CCTV coverage with perimeter monitoring available.

• The vehicles entering the refinery should be fitted with spark arrestors.

• Routine checks to be done to ensure and prevent the presence of ignition sources

in the immediate vicinity of the refinery (near boundaries).






• Clearly defined escape routes shall be developed for each individual plots and

section of the INDMAX unit taking into account the impairment of escape by

hazardous releases and sign boards be erected in places to guide personnel in case

of an emergency.

• Well defined muster stations in safe locations shall be identified for personnel in

case of an emergency.

� Windsocks existing in all prominent locations with clear visibility.

� Identification of critical equipment’s done & inspection of methodologies

existing for inspection during shutdown.

� The active protection devices like fire water sprinklers and other protective

devices shall be tested at regular intervals.

� SOP should be established for clarity of actions to be taken in case of fire/leak

emergency.

General conclusion and Recommendations:

1. In case of tanks on fire the heat radiations from the tank on fires will slightly affect the

INDMAX Unit but the intensity is not so high to cause major damage to the unit. Fixed

water sprays system is available on all nearest tanks, irrespective of diameter where

inter distances between tanks in a dyke and/or within dykes are not meeting the

requirements of OISD-STD-118.

2. Ensure that combustible flammable material is not placed near the Critical instrument of

the INDMAX Unit. These could include oil filled cloths, wooden supports, oil buckets

etc. these must be put away and the areas kept permanently clean and free from any

combustibles. Secondary fire probability would be greatly reduced as a result of these

simple but effective measures.

3. Sprinklers and foam pourers provided. Monitors & hydrants located at a distance more

than 15 meters.

4. ROSOV and Hydrocarbon detectors to be provided with the nearest tank of the INDMAX

unit.

5. Since Refinery operation is being done 24 hourly. Lighting arrangements are available in

line.






CHAPTER 8






CHAPTER 8

PROJECT BENEFITS 8.1 Project Benefits

The revamp project is being implemented for improvement of revenue and emissions of the

refinery.

Details of the benefits from the proposed project are given below.

BGR is implementing the following projects:

1) Crude processing capacity enhancement from 2.35 MMTPA to 2.7 MMTPA

2) DHDT capacity enhancement from 1,200 TMTPA to 1,800 TMTPA to meet BS-

V/VI HSD specification.

3) CRU-MSQ revamp to meet BS-VI MS specification.

4) INDMAX Project along with Indmax Gasoline De-Sulphurisation Unit.

5) Selective Desulphurisation (SDS) Unit. 6)

In view of the Auto-Fuel Policy Vision 2025, the Refineries will be required to supply fuels

meeting the BS-IV specification fuels by 1st April 2017 and BS-V/VI specification by 1st April,

2019.

The expansion, revamping, installation of INDMAX will aid in manufacturing and eliminating

the production demand of Black Oil and Naptha. It will maximize the production of high

value of LPG. The project will help to manufacture High Speed Diesel (BS- VI). High Speed

Diesel (HSD) conforming to manufacturing specifications of BS- VI.

The increased capacity will fulfill the current public demand of fuels.

8.2 Direct Benefits

(Increased Processing Capacity & Improved Product Yields)

1) The expansion, revamping, installation of INDMAX will aid in manufacturing and

2) Eliminating the production demand of Black Oil and Naptha.

3) It will maximize the production of high value of LPG.

4) The project will help to manufacture High Speed Diesel (BS-VI).

5) High Speed Diesel (HSD) conforming to manufacturing specifications of BS- VI.

6) Availability of LPG will discourage deforestation and reduce the use of fire wood

& fossil fuels.

7) Improve the quality of life of women engaged in household activities specially in

cooking.

8.3 Improvement in the Social Infrastructure

The expansion of Plant will create opportunities for direct and indirect employment in the

area. This will initiate local economic growth and thereby the potential to enhance quality of

life of the local communities. Local population will get benefited due to availability of safer

fuels.

8.4 Reduction of Emissions

The BS-VI will bring down the Nitrogen Oxide emissions from diesel cars by 68 % and 25%

from petrol engine cars. Cancer causing particulate matter emissions from diesel engine cars

will also come down by a phenomenal 80 %. Besides, the project would also improve the

smoke point of the kerosene stream from the Assam. It will, therefore, help in maintaining

cleaner environment due to reduction in emissions.






CHAPTER 9






CHAPTER 9

ENVIRONMENTAL MANAGEMENT PLAN

Environmental Management Plan (EMP) is the planning and implementation of various

pollution abatement measures for the proposed projects at BGR. The EMP lists out all the

measures to be taken during the Design/Engineering, Construction, Commissioning and

operational stages of the project.

As discussed in the impact identification (Chapter-4), the major impact during the

construction phase will be due to the site grading activities and due to mobilisation of the

work force, though marginal and of short duration.

During operational phase, the area of concern will be stack emissions, liquid effluent and

intermittent disposal of spent catalyst (solid waste) from the proposed During operation

there will be stack emissions from INDMAX FCC generator, IGHDS unit, CDU-II, DHDT unit,

and CRU unit, plant after expansion.

The Environmental Management Plan (EMP) for the proposed projects has to ensure that

the residual environmental impacts are minimized by adopting best possible economically

viable techniques. The EMP also has to ascertain compliance with all statutory conditions as

per No Objection Certificate (NOC) from Pollution Control Board Assam and Ministry of

Environment & Forests.

A comprehensive plan has been worked out keeping in view these requirements. The plan

encompasses the mitigation in three stages i.e. design, construction and operation of the

plant. The proposed EMP appropriate for each stage is described in the subsequent sections

of this chapter.

IOCL is a vibrant, integrated and diversified petroleum company of national importance

committed to sustainable development. IOCL have sound Environmental Management

System and Occupational Health and Safety Management Systems in place for carrying out

their operations in a manner consistent with its commitment to sustainable development. In

recognition of their well designed and maintained systems, Bongaigaon Refinery has been

certified with ISO 14001:1996 and OHSAS 18001:1999 Company.

The company strives to remain as an environmentally responsible corporate citizen in its

products, activities and services and for continual improvement in its environmental

performance, as enunciated in their Safety, Health and Environment Policy, given below:

9.1 SAFETY, HEALTH & ENVIRONMENTAL POLICY

• Ensure that high standards for the safety of the people, processes and assets are

established and maintained.

• Comply with all Rules, Regulations & Statute on Safety, Occupational Health and

Environmental Protection.

• Plan, design, operate and maintain the facilities, processes and procedures for






sustained Safety, Health & Environmental Protection.

• Adopt and promote industry best practices to avert accidents and improve SHE

performance

• Remain trained, equipped and ready for effective & prompt response to accidents &

emergencies.

• Conserve key resources, minimum waste generation and ensure environmentally

safe disposal of inevitable waste.

• Make all efforts to preserve our ecological balance and heritage.

• Be a frontrunner in Safety, Occupational Health and Environment Protection through

continual improvement.

9.2 DESIGN PHASE

The EMP in the design stage endeavours to mitigate the problems related to health, safety

and environment at the process technology/source level itself. The proposed projects are

being designed by M/s. EIL taking into account various applicable international

standards/norms such as API, ASTM, BIS etc. Besides international standards, emphasis has

been given to comply with all applicable design standards/regulatory norms as specified by

Indian Authorities like IBR, OISD, CCE etc.

The design basis for all process units lays special emphasis on measures to minimize effluent

generation at source. The generated effluents shall be treated in the existing Effluent

Treatment Plant (ETP) to meet the stipulated treated effluent discharge standards viz.

Minimal National Standards (MINAS) for refineries.

The specific control measures related to gaseous emissions, liquid effluent discharges, noise

generation, solid wastes disposal etc. are described below:

9.2.1 AIR ENVIRONMENT

As a part of gaseous emissions control, proper fugitive emission control is also required. The

fugitive emissions originate from process vents, equipment leaks, storage tanks, wastewater

treatment systems etc. The following measures will be under taken to minimise these

emissions:

• Floating roof storage tanks will be provided with primary and secondary seals.

• Equipment leak detection and repair programs

• Selection of leak less equipment technology

• Minimum number of flanges and valves etc.

• High grade gasket materials for packing

• Use of state of art, low leakage valves preferably bellow seal

• Use of pumps with mechanical seals

9.2.2 WATER ENVIRONMENT

At the design stage, there are several measures proposed to be incorporated in the process

so as to minimize the impact of the projects during operational phase. The liquid effluents






generated from the proposed DHDT will be treated in the existing wastewater treatment

plants of Refinery and Petrochemicals.

9.2.2.1 IN-PLANT CONTROL MEASURES

In order to reduce the refinery's water consumption; the stripped sour water shall be used

for washing in DHDT Unit. This not only reduces the fresh water consumption and but also

reduces the net wastewater load to the ETP as well.

Provision of appropriate segregation and collection systems for various effluents, depending

on individual streams' characteristics. Paving the process area to avoid contamination of

soil/sub-soil/ground water in case of accidental spills/leakage of hydrocarbon liquids.

9.2.3 NOISE ENVIRONMENT

Comprehensive measures for noise control, at the design stage shall be followed in terms of

• Noise levels specification of various Rotating Equipment as per Occupational Safety and

Health Association (OSHA) standards.

• Equipment layout to consider the segregation of high noise generating areas.

• Erecting suitable enclosures if required to minimise the impact of high noise generating

sources.

9.2.4 LAND ENVIRONMENT

During the design stage, due care has been taken to select the process technologies

generating minimum solid wastes so that their handling, treatment and disposal does not

cause any serious impact on the existing land environment. Emphasis also has been made to

recycle some of spent catalysts by way of returning to the original supplier for reprocessing

will be specifically emphasized.

9.2.5 GREEN BELT DEVELOPMENT

In order to improve the aesthetic environment in and around the plant, BGR has been

developing green belt around the plant boundary. The details of Land cover and green cover

in the factory area are given in the following Table 6.1 Table no.6.1: The details of land cover and green cover

Details of Land cover Area in acres

a) Walled area 653

b) Area outside the walls (30 m belt) 51

Total factory land 704

Details of green cover

a) Natural forest cover 160

b) Tree plantations 56

c) Grass cover 50

d) Total green cover (a+b+c) 266

Green cover as % of walled area 40.7%






9.3 CONSTRUCTION PHASE

Environmental impacts during the construction phase can be attributed to the site

preparation activity and the mobilization of workforce. The EMP for this phase is described

below.


Dust generated as result of clearing, levelling and site grading operations will be suppressed

by using water sprinklers if dusty conditions are encountered. It will be ensured that the

construction machinery using diesel driven prime movers are properly maintained to

minimize exhaust emission of CO, SPM and HC. Dust suppression measures like water

sprinkling will be done as per requirement. The Construction activity will be restricted to day

time as far as possible to avoid disturbance to surrounding areas.

9.3.2 NOISE ENVIRONMENT

All noise generating equipment’s used during the construction phase shall be provided with

noise control devices. Wherever required, personal protective equipments such as earplugs,

earmuffs etc. will be provided to the persons engaged in noisy operations. This will minimize

their exposure to noise levels.

9.3.3 WATER ENVIRONMENT

The water requirement for the construction phase shall be provided through the existing

tube well tapping system. Potable water and proper sanitation facilities will be provided to

the construction workers at the site.

9.3.4 LAND ENVIRONMENT

Surplus earth (if any) and Construction debris will be used for landfill/site gradation. Metal

scrap and packaging materials will be sold for reprocessing.

9.3.5 CONSERVATION OF GREENERY

The site of construction is within premise of existing refinery. The area which is earmarked

for construction of the plants is having 450 nos. of trees (approx.).

9.3.6 SAFETY MEASURES

The site will have necessary security arrangements to prevent entry of unauthorized

personnel and proper control of hazardous materials on site. All the employees, with special

emphasis on contractor employees, will be trained in safety aspects related to their job.

There will be a special emphasis on safe handling of material, safety in welding and

fabrication activities and safety in working at heights. All the personnel will be provided with

safety appliances such as face shields, helmets, safety goggles, safety shoes, hand gloves

etc. as per the job requirement

9.3.6.1 STORAGE AND HANDLING OF HAZARDOUS CHEMICALS

Hazardous chemicals (if any) used during the construction will be stored and handled as per

the statutory regulations in line with Hazardous waste (Management and Handling) rules

notified in 1989 (provide for a control on the generation, collection, treatment, transport,






import, storage disposal of waste) and amendment of these rules in 2000 under the

Environment (Protection) Act, 1986.

9.3.7 SOCIO-ECONOMIC ENVIRONMENT

The demand for work force provides ample opportunities for providing temporary skilled,

unskilled and semiskilled labour. It is expected that the unskilled and semi skilled labour

would be available from the adjoining villages. However there would be influx of skilled and

specialised manpower to the area, which would create demand for housing and other

facilities.

Therefore, to avoid problems related to housing and hygiene preference will be given to

local people.

Adequate sanitation facilities and emergency medical services will be provided to meet the

workforce requirement during the construction phase. M/s BGR already have 30 bed

hospital available in the township and would be available to handle emergency situations.

9.4 OPERATIONAL PHASE

It is envisaged that with strict adherence to the pollution prevention and control measures

during the design stage of the projects, the environmental impacts could be moderated to

the minimum possible level during the operation phase.

The environmental management plan during the operational phase of the plant shall

therefore be directed to the following:

• Ensuring the operations of various process units as per specified operating

guidelines/operating manuals.

• Strict adherence to maintenance schedule for various machinery/equipment.

• Good Housekeeping practices

• Post project environmental monitoring

The following subsections discuss in brief the management plan for individual components

of environment.


9.4.1.1 IN-PLANT CONTROL MEASURES

Some of the important operational measures, which can reduce the impact on air

environment, are as follows:

• Low sulphur containing crude should preferably be processed

• Low Sulphur fuel oil should be fired in all the oil fired heaters/boilers.

• To control fugitive emission from the Hydrocarbon processing areas, the valves,

flanges pumps and Compressors seals; the gasket materials etc. should be

maintained on periodical basis.






• The loading / unloading operation from the storage tanks should preferably be

done during early part of the day when ambient temperature is low.

• The flaring of hydrocarbons should be avoided to the extent possible.

9.4.1.2 STACK MONITORING

In order to keep a check on the emissions of various criteria air pollutants viz. SO2, NOx,

SPM, CO from all the point sources viz. all heater stacks, Boiler stacks of existing refinery are

being monitored with the help of on-line analysing instruments for one or more of these

pollutants depending upon the type of fuel being used there. The various new stacks of

proposed projects will also be connected to the existing on-line monitoring network.

9.4.1.3 AMBIENT AIR QUALITY MONITORING

Five Ambient Air Quality Monitoring stations have been set up in consultation with PCBA and

have been operating in routine manner. These stations measure all the conventional

pollutants SPM, SO2, NOx and CO. Since, additional emissions due to the plant are minimum

and are predicted to have negligible impact on the surrounding air quality; it is suggested

that the existing facilities may continue to be used for Post Project Air Quality Monitoring.

9.4.1.4 MICRO-METEOROLOGICAL MONITORING

In order to effectively co-relate the stack emissions and the real time ambient air quality, the

air pollutants dispersion modelling needs the real time micro-meteorological data also.

Therefore, micrometeorology is being currently monitored within the plant site area to

measure parameters like wind speed, wind directions, ambient temperature, Relative

Humidity, Cloud cover, rainfall etc.

9.5 END-OF-PIPE (EOP) TREATMENT

As mentioned above, conceptualization of proper segregation and collection philosophy for

various effluents to be generated optimizes both technically and economically the design of

End-of-Pipe (EOP) Treatment or Waste Water Treatment Plant (WWTP) or Effluent

Treatment Plant (ETP).

9.5.1 EFFLUENT SEGREGATION AND COLLECTION PHILOSOPHY

In the INDMAX-IGHDS unit, the liquid effluent generated from the process (28.0 m3/hr.) No

additional effluent will be generated from CDU-II, CRU-MSQ, DHDT, SDS units. The effluent

will be treated in the Waste Water Treatment Plant (WWTP) and Tertiary Treatment Plant

(TTP). The treated effluent will be reused to the maximum extent possible to reduce

discharge to outside. Proper measures will be taken to meet the liquid effluent quality in

compliance with the proposed CPCB guidelines

In DHDT the waste water from pump pedestal and cooling, spent caustic during catalyst

generation, blow down from WHB and sulphur condenser stripped sour water streams from

various processing units are primarily contaminated with oil and grease, NH3, H2S, Na2SO3,

Na2CO3, NaHCO3, Bio-chemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD)

etc. Therefore, these streams are routed through oily water sewer (OWS) system to the

existing effluent treatment plant.






The detailed description of existing effluent treatment plants are described in the following

section.

9.5.1.2 EXISTING EFFLUENT TREATMENT SYSTEM

The refinery wastewater includes Phenol, sulphide, hydrocarbon, oil & grease, etc. The oil

may appear in wastewater as free oil, emulsified oil and as a coating on suspended matter.

Oily waste streams from process units, laboratory, process/off-site pumping stations, loading

areas, pipe trench drainage, etc. are collected in the main receiving sump and pumped by

screw pump to TPI. After free oil removal in TPI the effluent is collected in sump and transfer

to the surge pond. After the surge pond the total flow is taken to dissolved air flotation unit

through chemicals. The separator removes most of the remaining free-floating oil from

wastewater.

After this, pH of the wastewater, which is free from oil, is adjusted by sulphuric acid in the

tank to about 7.5 to 8.0. Thereafter, the effluent goes to The trickling filter along with

screened, degritted, domestic sewage (From canteen/toilets etc.) from the plant area. The

effluent from the trickling filter is taken to the transfer sump from where a part of it is

recirculated back to the trickling filter and the remaining part is sent to the aeration tank.

Nutrients mainly nitrogen and phosphorous in the form of urea and phosphoric acid are

added to feed chamber of bio -filter for the proper oxidation of the organic matter. Ferrous

sulphate is added to the inlet of aeration tank to take care of the traces of hydrocarbons.

The oxidised effluent is taken to final clarifier for the separation of the settle able

sludge/solids and the clear effluent is collected in the guard pond for further treatment in

Tertiary Treatment Plant (TTP).

The sludge from oil separator and clarifier are pumped to the sludge lagoon meant for the

storage of oily sludge and final disposal. The skimmed oil from TPI separators and surge

pond is pumped to slop oil storage tank.

The designed capacity of ETP is 180 m3/hr of industrial effluent and 60 m3/hr of township

effluent in normal dry weather condition and 650 m3/hr (wet weather flow).

9.5.1.3 PETROCHEMICAL EFFLUENT SEGREGATION AND COLLECTION PHILOSOPHY

The petrochemicals wastewater includes formaldehyde, methyl benzoate, organic acid and

hydrogen sulphide or sulphide as pollutants. The sanitary sewage coming from Township is

also treated in the effluent treatment plant.

The effluent along with cooling tower blow down goes to a surge pond. The quantity of

effluents generated from these sources is about 40 m3/hr recirculated to surge pond for the

dilution of waste and make it treatable. Oil skimming devices are provided for skimming the

floating oil in the surge pond. After separating the oil, the wastewater is subjected to two-

stage biological treatment i.e. high rate trickling filter and extended aeration type activated

sludge process.






The required amount of nutrients is added before the wastewater is sent to biological

treatment. The sanitary waste from Township, at a rate of 135 m3/hr, after passing through

the screen and grit chamber goes to the aeration tank. The part of the outgoing stream from

bio filter is recirculated to bio-filter. The remaining part of the effluent goes to clarifier for

separation of settle able solids. The sludge from the clarifier is taken to sludge thickener. The

sludge from final clarifier is taken to biological sludge sump where a part of it is fed to

biological reactor to maintain a particular level of mixed liquor suspended solids (MLSS) in

the reactor.

9.5.1.4 REUSE AND DIPOSAL OF TREATED EFFLUENT

The treated effluent from the treatment plant is stored in guard ponds. There are 6 numbers

of guard ponds i.e. 2 numbers (1800x2 m3) for old refinery section, 2 numbers (1800x2 m3)

for refinery expansion section and 2 numbers (1000x2 m 3). The guard ponds are meant for

final quality assessment and temporary storage before being taken to the clear water pond

of 22500-m3 capacity for Tertiary Treatment Plant (TTP) and make the water reusable.

The TTP consists soda-lime treatment, clari-flocculation, sand filtration and chlorination.

The tertiary treated water is sent to the cooling towers. The capacity of the TTP is 400 m3/hr.

There is provision for discharge of water from the guard ponds and clear water pond also in

the event of maintenance of the TTP. However, the treated water quality always meets the

required standards by PCBA.

In order to ensure that treated effluent from the refinery does not have any perceptible

impact on the surrounding water bodies, primarily ground water, the treated effluent shall

conform to MINAS, a part of the treated effluent shall be treated in TTP and reused for

cooling water in the refinery and petrochemical complex.

The entire quantity treated wastewater will be reused for cooling tower makeup and for

green belt

9.6 NOISE ENVIRONMENT

As incorporated during the design stage, the in-plant areas where noise levels are high

enough to have adverse impacts, the usage of ear plugs or earmuffs shall be strictly

enforced.

Further, the plantation of suitable plants species to reduce noise levels within the refinery

area shall also be taken on priority basis. Although the predicted noise level rise outside the

plant battery limit is very marginal and is unlikely to have any adverse impact on the

surrounding community, it is proposed to monitor the noise in the operational areas near

the refinery in connection with noise minimization program.

The brief description of Noise abatement measures of existing refinery are described below:






9.6.1 Noise abatement measures

Most of the units are open type. As a practice, the equipment selection emphasizes on the

aspect of low noise. A silencer has been installed in the Captive Power Plant boilers and this

has minimised the high noise generated during the start – up/shut-down of boilers.

Condition monitoring is conducted in all rotating equipment to maintain vibration and noise

levels within tolerance limits as laid down in the Factories Act.

In those specific areas/operations such as Turbo Generator of Captive Power Plant, where

there may be noise levels around 90 dB (A), exposure duration is maintained within

permissible limits. Operation and maintenance personnel who are required to be present

near high noise sources for operation/maintenance exigencies (even for short duration) are

provided with personnel protective equipment such as earplugs and earmuffs.

Noise in different work areas (quarterly) and ambient noise are monitored using Bruel and

Kjaer (Denmark) make precision sound level meter, type 2232.

9.7 GROUND WATER

The study area is rich in ground water availability and has tremendous potential for ground

water. The water required for the refinery is being tapped from the tube wells, which are

located around the refinery complex. These will be tapped in sequential manner. The

tapping will be done so as to have maximum radial separation between tube wells.

9.8 LAND ENVIRONMENT

9.8.1 IN-PLANT CONTROL MEASURES

The solid waste generated in the form of packaging material etc. shall be sold off for making

it suitable for reuse by reprocessing. More options shall be looked into for reducing the oily

sludge’s to be generated in the ETP by modifying the operating practices in the crude /

produce tank farm area and processing unit areas. In order to improve the aesthetics of the

plant, extensive horticulture development and landscaping within and around the plant

boundary shall be taken up.

The solids wastes identified to be disposed off in the landfill shall be done as per established

procedure for land filling.

9.8.2 SOLID WASTE DISPOSAL

Primarily, spent catalyst solid waste is generated from the proposed CDU, DHDT, CRU-MSQ,

INDMAX-IGHDS. The spent catalysts from DHDT and HGU can be sent back to catalyst

suppliers. The spent catalyst from SRU, activated carbon from ARU and Spent molecular

sieve from PSA shall be used as land fill/road making.

The solid waste handling, treatment and disposal of the existing project facilities and oily

sludge from proposed Projects are described below:

The solid waste generated at site can be broadly categorized as process related waste and






general solid waste. The process related solid waste includes the spent catalyst, oily sludge’s

and ETP sludges. The miscellaneous solid waste is the ones that are generated from various

establishments within refinery complex and include construction debris, general refuses,

workshop waste etc.

9.8.2 .1 PROCESS RELATED WASTES

Process related wastes are primarily two types.

1. Spent catalyst

2. Oily Sludge

1. Spent catalyst

The spent catalyst is generally alumina pellets impregnated with Co/Mo/Ni. These catalyst

life varying from 2-5 years are disposed thereafter. Spent Catalyst will be sold to authorized

parties/ CPCB registered recyclers or returned to supplier for reprocessing.

2. Oily Sludge

As the proposed plant unit generates only a fraction of total waste generated, hence

subsequent increase in ETP sludge generation will also be marginal. Hence, existing solid

waste handling treatment and disposal facilities will be utilized for this purpose. The details

of generation of oily sludge from various units of existing refinery and its treatment are

described below.

The oily sludge generated from various operations of the refinery can be divided into two

main categories:

Intermittent wastes

- Crude tank bottoms

- Product tank bottoms

- Kerosine filter clays

- Lube oil filter clays

- Pond sediments

- Coke fines

- Silt from storm water run off

- Cleaning of oil water sewer system

- Cleaning of oil spills

-

Continuously generated waste from effluent treatment plants

- API separator sludge

- Dissolved Air Flotation (DAF) float

- Slop oil emulsion






OILY SLUDGE GENERATION/HANDLING

Oily sludge generated from above mentioned sources are being stored in a 4000 m3 lined

lagoon located in the effluent treatment plant since March 1988 when the first HSD tank was

cleaned. (Prior to this, some small quantity of oily sludge was generated by way of cleaning

of API oil separators/surge ponds/oil spills etc. and this was transferred to the sludge lagoon

from 1979 to 1987). Thereafter the south side sludge lagoon was designated as an oily

sludge lagoon and subsequently all tank cleaning sludges as also the oily waste generated

from waste water treatment plant is transferred to the lagoon.

IOCL has awarded the contract M/s Balmer Lawrie & Co. Ltd. Kolkata for processing of Oily

Sludge for recovery of oil and Bio-remediation of residue. Processing of sludge along with

Bio-remediation of residual solid are completed.For stored oily sludge, methodology for

treatment applying bio remediation is under progress.

9.8.2 .2 STORAGE AND HANDLING OF HAZARDOUS WASTE/CHEMICALS

The Hazardous Waste/Chemicals during the operation stage will be stored and handled as

per the statutory regulations in line with Hazardous waste (Management and Handling) rules

notified in 1989 (provide for a control on the generation, collection, treatment, transport,

import, storage disposal of waste) and amendment of these rules in 2000 under the

Environment (Protection) Act, 1986.

9.8.2 .3 GENERAL SOLID WASTES

The general solid wastes are non – hazardous, non-recyclable, solid waste consisting of

waste refractory, spent insulation, used filter cartridges, spent charcoal, spent clay and sand

shall be generated. These wastes shall be disposed off in land fill.

9.9 SOIL QUALITY MONITORING

The periodic monitoring of soil and subsoil characteristics in and around the plant area, the

landfill site is being done at regular interval of time. The important physico-chemical and

biological parameters of the soil are monitored to evaluate the impact on the land

environment.

9.10 BIOLOGICAL ENVIRONMENT

As discussed earlier in impact prediction and evaluation chapter that the proposed project

does not portend any direct primary impact to the ecological components of the area.

IOCL is actively taking part in the overall development of the area. Regular safety and

environmental awareness programmes are being conducting in the nearby villages to

promote awareness of the local villages. BGR is also taking up social forestry programme to

promote clean and green drive. The periodic health check programmes for the nearby

villages is also being taken care.

9.11 ENVIRONMENTAL AUDIT

Environmental audits will be carried out on annual basis as per regulatory requirements.

Records of quality and quantity of air emissions and liquid effluent will be maintained.

Details of solid waste disposed will be recorded on regular basis. An inventory of waste






storage area in the refinery complex will be maintained, which include details of the type of

waste, location and quantity stored. Address of buyers of refinery wastes and details of

proposed use of waste will also be maintained. Data on influent to the effluent treatment

plant and treated effluent quality, stack emissions will be used to ascertain compliance with

stipulated standards.

The quantity of waste generated from various units will be compared with previous years

data and efforts will be made to minimize wastes for more efficient utilization of resources

9.12 ENVIRONMENTAL CELL AND MANAGEMENT

The Refinery has all elaborate relevant facilities required for environment management and

monitoring.

The Health Safety and Environmental Management at BGR is carried out by Deputy General

Manager (Health, Safety & Environment). The DGM (HSE) reports to GM (TS & HSE). The HSE

team comprises of Chief Manager, Senior Manager, Manager and executives.

9.13 SOCIO-ECONOMIC ENVIRONMENT

There are about 1162 regular employees in the existing refinery, as on 1st may 2016. An

additional staff of 20 will be required for proposed projects. Besides the remuneration

package, the employees shall be entitled to the benefit, like family health scheme,

transportation facilities, recreational facilities etc.

Bongaigaon Refinery is taking care of adequate measures to provide safe working

environment, safeguard occupational health and hygiene of the employees.

Bongaigaon Refinery is actively taking part in the overall development of the area. Regular

safety and environmental awareness programmes are being conducting in the nearby

villages to promote awareness of the local villages. Bongaigaon Refinery is also taking up

social forestry programme to promote clean and green drive. The periodic health check

programmes for the nearby villages is also being taken care.






CHAPTER 10






CHAPTER 10

DISCLOSURE OF CONSULTANTS

10.1 Introduction

This chapter describes about the environmental consultant – “ABC Techno Labs India

Private Limited” engaged in preparation of EIA report for capacity expansion, revamping &

implementation of INDMAX technology at the Bongaigaon Refinery & Petrochemicals, IOCL,

Assam.

10.2 The Consultant: ABC Techno Labs

ABC Techno Labs India Private Limited (formerly ABC Environ Solutions Pvt. Ltd.) is an ISO

9001, ISO 14001 & OHSAS 18001 Certified Company & leading Environmental Engineering &

Consultancy Company constantly striving towards newer heights since its inception in 2006.

Our Company is dedicated to provide strategic services in the areas Environment,

Infrastructure, Energy, Engineering and Multilab.

It is the first firm to be accredited by NABET (National Accreditation Board for Education and

Training), Quality Council of India, as an EIA Consultant, approved for carrying out EIA

studies and obtaining environmental clearance for various sectors such as Thermal Power

Plants, Infrastructure, Industrial Estates / Complexes/ Areas, Mining, Township & area

development and Building construction projects etc. ABC Techno Labs is equipped with in-

house, spacious laboratory, accredited by NABL (National Accreditation Board for Testing &

Calibration Laboratories), Department of Science & Technology, Government of India.

Since establishment ABC Techno Labs focus on sustainable development of Industry and

Environment based on sound engineering practices, innovation, quality, R&D and most

important is satisfying customers need. The company has successfully completed more than

100 projects of variety of industries, in the field of pollution control and environmental

management solutions. The company is also dealing in the projects of waste minimization

and cleaner production technology.

The team of technocrats and scientist are well experienced to deal with the design,

Manufacture, Fabrication, Installation, commissioning of Effluent/Wastewater treatment

plants, Sewage Treatment plants, and Combined Treatment plants.

The company is having well experienced team of Scientists & Engineers who are looking

after environmental projects & well equipped analytical laboratory with a facility including

analysis of physical, chemical and biological parameters as per the requirements of the State

Pollution Control Board and our clients.

10.3 Services of ABC Techno Labs India Private Limited






10.3.1 Environmental Services

• Environmental Impact Assessment (EIA)

• Environmental Management Plan (EMP)

• Social Impact Assessment (SIA)

• Environmental Baseline data collection for Air, Meteorology, Noise, Water, Soil,

Ecology,Socio-Economic and Demography etc;

• Environmental Monitoring

• Socio Economic Studies

• Resettlement & Rehabilitation Plan

• Ecological & Human Health Risk Assessment Studies

• Ecological Impact Assessment

• Environmental Management Framework

• Solid Waste Management

• Hazardous Waste Management

• Internship & Training

10.3.2 Turnkey Projects

• Water Treatment Plants

• Sewage Treatment Plant

• Recycling & Water Conservation Systems

• Zero Discharge System

10.3.3 Other Services

• Operation & Maintenance of Water & Waste Water Plants

• Water & Waste Water Treatment Chemicals

• Pilot Plant studies

• Feasibility studies & preparation of budgetary estimates

10.3.4 Laboratory Services

• Chemical Testing

• Environmental Testing

• Microbiological Testing

• Food Testing

• Metallurgical Testing

10.4 Sectors Accredited by NABET (QCI)

“ABC Techno Labs India Private Limited” listed at Sr. No. 2 in List of Accredited EIA

Consultant Organizations –169 (as on Nov. 05, 2015)

http://www.qcin.org/nabet/EIA/documents/Accredited%20consultants.pdf

S. No. Sectors Name

1. Mining of minerals (Opencast only) Mining (Open cast and






Underground)

2. Irrigation projects only

3. Thermal Power Plant

4. Metallurgical industries (sec. ferrous only)

5. Cement Plants

6. Petroleum refining industry

7. Leather/skin/hide processing industry

8. Chemical Fertilizers

9. Synthetic organic chemicals industry (dyes & dye intermediates; bulk

drugs and intermediates excluding drug formulations; synthetic

rubbers; basic organic chemicals, other synthetic organic chemicals

and chemical intermediates)

10. Distilleries

11. 24 Pulp & paper industry excluding manufacturing of paper from

wastepaper and manufacture of paper from ready pulp without

bleaching

12. Isolated storage & handling of hazardous chemicals (As per threshold

planning quantity indicated in column 3 of Schedule 2 & 3 of MSIHC

Rules 1989 amended 2000)

13. Airports

14. Industrial estates/ parks/ complexes/ Areas, export processing

zones(EPZs), Special economic zones (SEZs), Biotech parks, Leather

complexes

15. Ports, harbours, jetties, marine terminals, break waters and dredging

16. Highways, Railways, transport terminals, mass rapid transport

systems

17. Common effluent treatment plants (CETPs)

18. Common municipal solid waste management facility (CMSWMF)

19. 38 Building and large construction projects including shopping malls,

multiplexes, commercial complexes, housing estates, hospitals,

institutions

20. Townships and Area development Projects

10.5 Study Team for EIA Study

ABC Techno Labs India Private Limited has carried out this Environmental Impact

Assessment (EIA) study. The multidisciplinary team included expertise in Environmental

Impact Assessment, Air & Water Pollution & Control measures, Noise Control measures,

Ecology & bio-diversity, Land use, Geology, Environmental Chemistry and Socio-Economic

planner. The team members involved in EIA study area:

S. No. Name Role

1. Dr. Muthiah Mariappan EIA coordinator,

2. Dr. R.K. Jayaseelan Functional Area Expert – Land use, Water






S. No. Name Role

Pollution, Prevention & Control and Hydrogeology

3. Dr. Chaitanya Sathe EIA Coordinator & FAE – Water Pollution & EIA

Review

4. Mr. Sameer Zope Manager Operations- Documentation,

Preparation of Reports & Reports Analysis

5. Mr. Trushant Gharjare Project Engineer – Preparation, documentation of

reports and Report Analysis

6. Ms. Diya Mistry Project Engineer – Preparation, documentation of

reports and Report Analysis

7. Mr.Bipin Prakash Chari

AFAE-Water Pollution

Project Engineer

(Report Analysis and Documentation)

8. Dr.Muthiah Mariappan FAE – Solid Waste Management

9. Mr. Mohammed Assain AFAE- Air Pollution, Solid and Hazardous Waste

Junior Project Engineer

10. Dr. N. Sukumaran FAE – Ecology & Biodiversity

11. Dr.Thillai Govindarajan FAE – Geology

12. Mr. M. Senthil Kumar FAE – Risk Assessment & Hazard management

13. Mr. R. Rajendran FAE – Air Pollution, Prevention and Control and

Noise & Vibration

14. Mrs. Geetha Shreeneevasakam FAE – Socio-Economic Expert

15. Mr. Robson Chinnadurai Senior Chemist

16. Mr. M. Muruganantham Junior Chemist

17. Mr. Sathish Field Technician

18. Mr. Satyawan D.Upale Field Technician






ANNEXURES






ANNEXURE I

QUALITY, SAFETY, HEALTH AND

ENVIRONMENT POLICY











ANNEXURE II



Assam


Refinery Flow Diagram



Assam



enhancement from 2.35 to 2.7 MMTPA, DHDT capacity enhancement from 1.2 to 1.8 MMTPA, CRU-MSQ revamp & implementation of SDS unit by M/s IOCL, Bongaigaon Refinery at Dhaligaon, Dist:



ANNEXURE III

PROCESS UNIT CAPACITIES





Process Unit Capacities Unit Installed Capacity

(TMTPA)

Existing Units:

Crude Distillation, CDU-I 1,350

Crude Distillation, CDU-II 1,000

Delayed Coker, DCU-I 500

Delayed Coker, DCU-II 500

Coke Calcination, CCU 75

Catalytic Reformer, CRU 160

MSQ 429

Diesel Hydrotreater, DHDT 1,200

Hydrogen , HGU 25

Unit Installed Capacity

(TMTPA)

New/Revamped Units:

INDMAX 740

Prime-G+ (IGHDS) 312

DHDT (revamped) 1800

CRU (revamped) 200

SDS 59

NHT 235

SRU 80





ANNEXURE IV

STORAGE DETAILS





Storage Details

Sl.

No. Tank No.

Tank No

(Tank Farm

wise)

Existing Product Capacity

in KL

Existing

Class Remarks

Under License No. P/HQ/AS/15/210 (P891)

1 47-13-001A 501 CRUDE 20000 A

2 47-13-001B 502 CRUDE 20000 A

3 47-13-001C 503 CRUDE 20000 A

4 47-13-001D 504 CRUDE 20000 A

5 47-13-002A 1708 RFN 2000 A

6 47-13-002B 1709 RFN 2000 A

7 47-13-003 1710 RFN 4000 A

8 47-13-004A 1705 BONMAX 500 B

9 47-13-004B 1707 BONMAX 500 B

10 47-13-005A 2601 SRN 5000 A

11 47-13-005B 2602 SRN 5000 A

12 47-13-005C 2604 SRN 5000 A

13 47-13-006A 2605 MS 3000 A

14 47-13-006B 2606 MS 3000 A

15 47-13-006C 2603 MS 3000 A

16 47-13-007A 1203 ATF TEST 1000 B

17 47-13-007B 1204 ATF TEST 1000 B

18 47-13-008A 1205 ATF 4000 B

19 47-13-008B 1206 ATF 4000 B

20 47-13-008C 1207 ATF 4000 B

21 47-13-009A 1801 SKO 2000 B

22 47-13-009B 1802 SKO 2000 B

23 47-13-009C 1803 SKO 2000 B

24 47-13-009D 1804 SKO 2000 B

25 47-13-010A 1906 HSD 5000 B

26 47-13-010B 1907 HSD 5000 B

27 47-13-010C 1908 HSD 5000 B

28 47-13-010D 1909 HSD 5000 B

29 47-13-010E 1910 HSD 5000 B

30 47-13-011A 1805 LDO 5000 C

31 47-13-011B 1806 LDO 5000 C

32 47-13-011C 1807 LDO 5000 C

33 47-13-011D 1808 LDO 5000 C

34 47-13-012A 1201 CFO 4000 C

35 47-13-012B 1202 LSHS / NCFS 4000 C

36 47-13-013 1903 HSD 300 B

37 47-13-014 1905 ATF DAY LOADING 500 B

38 47-13-015 1904 LVFO 500 C

39 47-13-016A 1901 HSD 300 B

40 47-13-016B 1902 HSD 300 B

41 47-13-017A 1106 HSD COMPONENT 4000 B





42 47-13-017B 1107 HSD COMPONENT 4000 B

43 47-13-017C 1108 HSD COMPONENT 4000 B

44 47-13-018A 1103 HSD COMPONENT 3000 B

45 47-13-018B 1104 HSD COMPONENT 3000 B

46 47-13-018C 1105 HSD COMPONENT 3000 B

47 47-13-019 1102 IDLE TANK 500 B

48 47-13-020A 801 RCO 10000 E

49 47-13-020B 802 RCO 10000 E

50 47-13-020C 803 RCO 10000 E

51 47-13-020D 804 RCO 10000 E

52 47-13-021A 805 SLOP 1000 A

53 47-13-021B 806 SLOP 1000 A

54 47-13-022 1701 LGO 1000 B

55 47-13-023 1703 HCN 1000 A

56 47-13-024 1702 FLUSHING OIL 1000 B

57 47-13-025A 1704 COKER RESIDUE 500 C

58 47-13-025B 1706 COKER RESIDUE 500 C

59 CPP-I 1403 IFO 300 B

60 CPP-II 1401 FO 1500 C

61 CPP-III 1402 FO 1500 C

62 23-T-001 1724 REFORMATE 1250 A

63 23-T-002 1725 REFORMATE 1250 A

64 26-T-001 1711 HOT OIL 400 C

65 47-T-001 1720 DESULPHARISED NAPHTHA (DSN) 800 A

66 47-T-002A 1714 MS/REFORMATE 1000 A

67 47-T-002B 1715 MS/REFORMATE 1000 A

68 47-T-003A 1712 REFORMATE/BLOWDOWN 500 A

69 47-T-003B 1713 COKER NAPHTHA (CN) 500 A

70 47-T-004A 1716 MTO 500 B

71 47-T-004B 1717 MTO 500 B

72 47-T-005A 1718 HCN 1200 A

73 47-T-005B 1719 HCN 1200 A

74 47-T-006A 1722 NAPHTHA 800 A

75 47-T-006B 1723 NAPHTHA 800 A

76 47-T-007 1721 NAPHTHA / SRN 1000 A

77 47-T-008 1726 NAPHTHA / LT SRN 350 A

78 V-264 V-264 (LAID OFF FROM SERVICE) Capacity 108 KL

79 47-13-009E 2607 SRN 4000 A

80 47-13-009F 2608 MS 4000 A

81 47-13-010F 2501 HSD 10000 B

82 47-13-010G 2503 HSD 10000 B

83 47-13-001E 505 CRUDE 20000 A

84 47-13-001F 506 CRUDE 20000 A

85 47-13-007D 1209 ATF TEST TANK 1000 B

86 47-13-021D 807 UNIT SLOP 1000 A

87 47-T-008A 1727 NAPHTHA / HY SRN 400 A

88 47-T-008B 1728 NAPHTHA / HY SRN 400 A

89 47-T-005C 2506 NCN 1200 A





90 47-T-027A 2701 MS 2000 A

91 47-13-028 2702 MS 500 A

92 47-13-005D 2706 MS 5000 A

93 47-13-010H 2505 HSD 10000 B

94 47-13-010I 2710 HSD 10000 B

95 47-13-027B 2703 MS 2000 A

96 47-13-027C 2704 MS 2000 A

97 47-13-027E 808 RCO 5000 E

98 47-13-027F 809 RCO 5000 E

99 47-13-009G 2708 HSD 5000 B

100 47-13-011E 1208 LDO 5000 C

101 47-13-009H 3201 SKO 5000 B

102 47-13-009I 3202 SKO 5000 B

103 47-13-029 1101 NEEDLE COKE FEED (NCFS) 5000 C

104 47-13-001G 507 CRUDE 20000 A

105 88-T-001 508 DHDT FEED (SR DIESEL, KERO-I&II) 20000 B

106 88-T-002 509 DHDT FEED (SR DIESEL, KERO-I&II) 20000 B

107 88-T-003 510 DHDT FEED (KERO / MIXED FEED) 20000 B

108 88-T-004 511 DHDT CRACKED FEED 20000 B

109 88-T-005 512 DHDT CRACKED FEED 20000 B

110 88-T-006 513 HGU FEED NAPHTHA 3000 A

111 88-T-007 514 HGU FEED NAPHTHA 3000 A

112 94-T-001A T-9401 LSFO 114 C

113 94-T-001B T-9402 LSFO 114 C

114 94-T-002A T-9403 NAPHTHA 900 A

115 94-T-002B T-9404 NAPHTHA 900 A

116 94-T-003A T-9405 HSD 275 B

117 94-T-002B T-9406 HSD 275 B

118 47-T-2510 T-2510 ISOMERISATE 4000 A

119 47-T T-New MS 10000 A

TOTAL CAPACITY 554828

Class Description

Capacity

as per

existing

Licence

Capacity

Proposed Difference

(A) STORAGE CAPACITY WITH CLASS 'A' IN KL 220950 230950 10000

(B) STORAGE CAPACITY WITH CLASS 'B' IN KL 230750 230750 0

(C) STORAGE CAPACITY WITH CLASS 'C' & 'E' IN KL 93128 93128 0

TOATAL IN KL 544828 554828 10000





ANNEXURE V

SULPHUR BALANCE





SULPHUR BALANCE

Crudes QTY,

KTPA SUL, Wt % TPD Crude

TPD

SUL

Assam Crude 320 0.2304 960 2.2

Bonny Light 286 0.16 858 1.4

Girasol 238 0.32 714 2.3

Hungo 238 0.58 714 4.1

Murban 286 0.74 858 6.3

Quaiboe 762 0.12 2286 2.7

Seria Light 143 0.07 429 0.3

Zafiro 332 0.25 996 2.5

Labuan 95 0.09 285 0.3

TOTAL CRUDE 2700 8100 22.1

TOTAL SUL IN FEED 22.1

PRODUCTS

QTY,

KTPA SUL, Wt % TPD

TPD

SUL

LPG 257 0 771.3 0.0

Regular Gasoline (BS III) 533 0.0007 1599.3 0.01

Diesel (BS III) 1347 0.0005 4042.2 0.0

SKO 136.0 0.0005 408 0.0

ATF 0.0 0.25 0 0.0

Naphtha Fuel Grade 33 0.024 100.2 0.0

Fuel Oil 0.0 0.48 0 0.0

LDO 0.0 0.4236 0 0.0

TOTAL PRODUCTS 2307.0 0.1

IFO 0.0 0.48 0 0.0

DCU Coke 62.0 0.8 186 1.5

INDMAX Coke 58.0 0.5 174 0.9

TOTAL 2.4

SULPHUR REJECTED 19.7

Existing Capacities

SSRU, TPD 10 10

TOTAL (EXISTING SRU), TPD 10

SULPHUR RECOVERY REQUIRED,

TPD 10





ANNEXURE VI

STACK DETAILS



Assam


IOCL - Bongaigaon Refinery Stack Details

Sl No Unit Shape of

Stack

Internal

Diameter

(M)

Height from

Ground Level

(M)

Exit Gas Temp Exit Gas Velocity

m/sec

ºC K min K max K (ref) Min Max

1 CDU-I Circular 1.77 47.85 260-365 533 638 533 10.0 15.0

2 CDU-II Circular 2.06 47.85 290-350 563 623 563 10.0 15.0

3 DCU -I Circular 2.35 57.40 300-350 573 623 573 10.0 15.0

4 DCU -II Circular 2.35 57.40 320-360 593 633 593 10.0 18.0

5 Reformer Circular 1.73 40.00 380-540 653 813 727 10.0 18.0

6 Hot Oil (26-F-1A) Circular 1.60 59.00 260-300 533 573 523 10.0 15.0

7 Hot Oil (26-F-1B) Circular 1.60 59.00 240-270 513 543 523 10.0 18.0

8 ISOM Circular 0.98 28.60 230 510 510 19.0

9 CCU Circular 3.51 40.30 330-400 603 673 603 10.0 15.0

10 CPP Circular 4.33 61.50 150-160 423 433 423 7.5 12.5

11 DHDT Circular 1.7 60.00 230-250 503 503 20.0

12 HGU Circular 1.6 60.00 150-160 423 423 20.0

13 GTG Circular 3.5 70.00 170-180 443 453 443 10.0 15.0





ANNEXURE VII

OILY SLUDGE MANAGEMENT PLAN





Oily Sludge Management Plan

Oily Sludge

The oily sludge generated from various operations of the refinery can be divided into two

main categories:

Intermittent wastes

- Crude tank bottoms

- Product tank bottoms

- Kerosene filter clays

- Lube oil filter clays

- Pond sediments

- Coke fines

- Silt from storm water run off

- Cleaning of oil water sewer system

- Cleaning of oil spills

Continuously generated waste from effluent treatment plants

- API separator sludge

- Dissolved Air Flotation (DAF) float

- Slop oil emulsion

Oily sludge generation/handling

Oily sludge generated from above mentioned sources are being stored in a 4000 m3

concrete lined lagoon located in the effluent treatment plant since March 1988 when the

first HSD tank was cleaned. (Prior to this, some small quantity of oily sludge was generated

by way of cleaning of API oil separators/surge ponds/oil spills etc. and this was transferred

to the sludge lagoon from 1979 to 1987). Thereafter the south side sludge lagoon was

designated as an oily sludge lagoon and subsequently all tank cleaning sludge as also the oily

waste generated from waste water treatment plant is transferred to the lagoon.

M/s Balmer Lawrie & Co. Ltd. Kolkata was engaged for processing of Oily Sludge for recovery

of oil and Bio-remediation of residue. Processing of sludge along with Bio-remediation of

residual solid are completed.

For stored oily sludge, methodology for treatment applying bio remediation is under

progress





ANNEXURE VIII

EFFLUENT TREATMENT PLANT DETAILS





Effluent Treatment Plant :

Treatment Approach:

The waste water treatment scheme for the refinery consists of inside battery limit auxiliary

treatment facilities which recover the major portion of free oil from concentrated oil

bearing streams at the point of origin, thereby reducing the oil load on main TPI oil

separator oil catchers as supplementary ISBL treatment facility is aimed at stage wise

maximum removal of hydrocarbons from concentrated streams before their dilution with

other waste water streams. Ponds/VOC tanks have also been equipped with oil skimming

facilities so as to remove oil at each successive possible stage.

The combined streams are then subjected to common treatment scheme comprising of

second stage physical oil separation, pH adjustment and two stage biological treatments

consisting of high rate trickling filter and extended aeration type activated sludge process.

The purpose of providing biological treatment in stages (trickling filter and activated sludge

process) is that waste water coming from surge ponds will contain, apart from phenol, oil

and sulphides in such concentration so as to make an activated sludge process work not so

efficiently. Trickling filter is known for its ability to accept and remove high concentration of

both oil and sulphides to a very low value which can be further taken care of in an activated

sludge unit. In respect of particularly the oil, trickling filter is known to reduce the same

from about 100 ppm to less than 15 ppm. The non-provision of intermediate sludge

entering from trickling filter would be helpful in developing and maintaining the mixed

liquor suspended solids concentration to desired value.

The final clarifier has been provided to remove settle able solids from the effluent. Active

biological sludge mass shall be recirculated in order to have the desired MLSS.

In order to have fairly uniform hydraulic as well as organic loading from the plant

throughout the year, which is required to the production of desired quality final effluent,

surge ponds have been provided for this purpose. The total combined flow from the

receiving sump shall be pumped by screw pumps to surge ponds via TPI.

Screw pumps have been provided for lifting raw waste from receiving sump to surge ponds

mainly because of the following advantages:

- Screw pumps are very efficient for a large variation of flows. They gently lift as much

as it comes for very low rate as well as peak flow conditions. Screw pumps are also

more efficient compared to centrifugal pumps for the conditions of low head and

high discharge.





- Screw pumps gently lift the waste water containing oil and thus avoiding churning of

the waste water during the course of pumping. As a result of this emulsification does

not take place and the physical removal of oil in the oil separators in much easier.

The designed flow from the TPI & VOC tanks/surge pond-I&II flows over to DAF section. DAF

section is removing practically most of the remaining free floating and emulsified oil from

the waste water. Oil free water from DAF section flows to pH adjustment tank where

sulphuric acid is dosed to reduce the pH to about 7.5 to 8.0

The effluent from DAF section shall be fed to trickling filter along with screened, regretted

domestic sewage from the complex. Filtered effluent shall be collected into the transfer

sump from where part of it shall be recirculated back to trickling filter and designed flow to

aeration tank. For the proper oxidation of organic matter contained in the nutrient deficient

waste, nutrients mainly Nitrogen and Phosphorus are added to feed chamber of bio filter in

the form of Urea and DAP. Required nutrient supply is beneficial for the microbial growth.

The aeration tank has been designed as deep oxidation ditch type. Oxidized effluent is

taken to the final clarifier for the separation of the settle able biological flocks, and the clear

effluent shall be collected in the guard ponds for final discharge to tertiary treatment

facility.

The biological sludge from the clarifier shall be collected in a separate sump from where

part of it shall be returned to aeration tank and surplus shall be transferred to the sludge

drying beds. The primary sludge from oil separators shall be pumped to the sludge lagoon.

The excess biological sludge from extended aeration type activated sludge process would be

quite small.

It has been proposed to dispose of all the oily sludge to a lagoon which is intended to accept

sludge for prolonged period and then be taken out of operation the supernatant containing

oil from the lagoons shall be brought to the oil sump and be pumped to the slop oil tank.

Guard ponds in duplicate have been provided so as to have batch wise operation. Guard

pond shall be sufficient for storing the treated effluent for a day which shall provide enough

time for checking the quality of the final effluent before its final discharge.

The contaminated cooling tower blow down shall be treated in circular oil separator, for

removal of free oil. The oil free blow down shall be discharged to the Guard Ponds. This will

further dilute the final effluent.

The skimmed oil from ISBL oil separator oil catchers (for tank bottom from crude tanks,

reduced crude and slop storage tanks), TPI separator, surge ponds, and sludge lagoons are

pumped to the slop oil storage tanks.

The final effluent from the plant is the following characteristics as envisaged in the consent

document of Assam State Pollution Control Board.





1. pH 6.0-8.5

2. Phenol 0.35 mg/l

3. BOD 15 mg/l

4. Sulphide 0.5 mg/l

5. O & G 5 mg/l

6. Suspended Solids 20 Mg/l

7. COD 125 mg/l

All other applicable characteristics of the treated effluent shall be as per IS: 2490-1974.

Waste Water Treatment Plant -Refinery Section:

Introduction:

The Waste Water Treatment Plant has been expanded for Refinery Expansion Project of

Bongaigaon Refinery , which has been enhanced its refining capacity to 2.35 MMTPA from

1.35 MMTPA. BGR is treating the waste water generated from the Refinery &

Petrochemicals area separately in an integrated Waste Water Treatment Plant. The treated

waste water is stored in guard ponds and further routed to clear water pond for tertiary

treatment.

Quantity and Quality of Waste Water and Treated Effluent:

Characteristic of Waste Water:

Up to Biological Unit:

1. Flow Rate

a) For TPI Units Stream I -150 M3/hr

Stream II - 500 M3/hr

b) For DAF Units Stream A - 60 M3/hr

Stream B - 120 M3/hr

2. PH 10.0 – 11.0

3. Oil & Grease 1050 mg/l

a) Feed Oil 735 mg/l

b) Emulsified oil 315 mg/l

4. BOD5 days 20oC 56 mg/l

5. Total suspended solids 200 mg/l

6. Phenol 55 mg/l

7. Hydrogen sulphide (H2S) 36 mg/l

8. Sodium sulphate 1000 mg/l

9. Mercaptans 8.0 mg/l





From Biological Unit & Onward:

1. Flow Rate 180 M3/hr (including sanitary flow)

2. BOD5 250 mg/l

Treated Effluent Quality:

1. pH 6.0-8.5


3. BOD3 day 27oC 15 mg/l

4. Total suspended solids 20 mg/l

5. Phenol 0.35 mg/l

6. Sulphides 0.5 mg/l

Design Basis:

Treatment Philosophy:

The effluent generated from the units mainly comprises of chemical and oily effluent. This

stream contains pollutants like oil, BOD, sulphides, Phenols and suspended solids. In

addition, sanitary waste from township and plants are required to be treated along with the

plant effluent for BOD removal.

The treatment philosophy contemplated thus involves physicochemical treatment for the

removal of suspended solids and oil followed by Biological treatment for the removal of

phenols, sulphides and BOD to produce a treated effluent that will meet the MINAS.

Treatment Scheme:

The free oil content of the process effluent is removed in Tilted Plate Interceptors by gravity

separation using the difference in specific gravities of oil and water. The effluent being

normally alkaline, of pH range 10-11 is neutralized by addition of sulphuric acid and brought

to neutral range which will aid to remove oily matter during further treatment.(Sulphuric

Acid dosing system for neutralisation is presently suspended for receiving effluents PH range

8-9 ).

The emulsified oil content of the effluent is removed by the addition of alum and de-oiling

polyelectrolyte followed by air floatation. The effluent free from both free and emulsified oil

is taken for biological treatment.

The dissolved organic matter present is removed by biological oxidation employing

extended aeration to achieve finer degree of treatment. Since the process effluent is devoid

of micronutrients, urea and di-ammonium phosphate are added to the biological oxidation

step. The mixed liquor from this step is taken to a radial flow classifier wherein gravity

separation of mixed liquor suspended solids taken place. The clear supernatant from

classifier will meet the MINAS for disposal.





The slop oil from TPI/VOC tanks is sent to storage tanks. The sludge from TPI/VOC tanks and

DAF is taken to sludge lagoon. The excess bio-sludge is solar dried in sand drying beds.

Product of the Treatment Facility:

Treated Effluent Quality:

1) pH 6.0 - 8.5

2) Oil & Grease 5 mg/l

3) BOD3 day 27oC 15 mg/l

4) Total suspended solids 20 mg/l

5) Phenol 0.35 mg/l

6) Sulphides 0.5 mg/l

Slop oil from Waste Water Treatment Plant:

The detailed calculation for the slop oil quantity is given in process design calculations. The

quantity of slop oil proposed to be collected from TPI unit is max of 2.4 M3/hr at 20%

concentration.

Sludge Production:

The sludge production is envisaged at mainly three units in the Waste Water Treatment

Plant i.e. at TPI, DAF and final clarifier (excess sludge). The sludge quantity proposed to be

produced at the above three units are given as below:

a) TPI (01 & 02) - 2.14 M3/hr 0.3% concn.

b) DAF (01 & 02) - 2.60 M3/hr 0.3% concn.

c) Final Clarifier - 27.8 M3/hr 0.1% concn.

Normal Operations Main Plant:

A. Admit effluent into Surge Pond-II via TPI. Surge Pond-II, has a capacity of 6000 M3

.The normal flow is 120 M3/hr. From the surge pond II effluents taken to the surge

pond I of capacity 3000 M3 through a inter connection line at the middle of the

ponds.

B. The flow will then go to the transfer sump from where the effluent is pumped to PH

adjustment tank.

C. The sulphuric acid is to be dosed into the pH adjustment tank at the inlet of the

tank.(Presently acid dosing is suspended).





D. When the effluent level reaches the top of the pH adjustment tank then the agitator

is to be started. Then the effluent transferred to flash mixer and flocculator where

alum and polyelectrolyte are added .Then the effluent routed to DAF section where

oily sludges are separated.

E. Flow then goes to sump S-I via original PH mixer from where it is pumped to bio filter

feed chamber. Only two of the four pumps are normally to be used.

F. In bio filter feed chamber, required quantities of nutrients, urea and DAP are to be

added.

G. The effluent flow to Sump S-2. Two of the pumps are normally in use. The flow will

be delivered to splitter box 1 from where it will go to bio-filter and balance to

aerator. This division is automatic and no operation is involved.

H. In the aeration tank, the aerators are to run all through the day. It is necessary to

maintain correct MLSS in the tank to get proper results

I. The effluent after aeration is led to the clarifier where the settle able material will

come down and the clear effluent goes to guard ponds. The clarifier machine must

run 24 hrs so that all material settled on the floor can be quickly sent to the sump S-

3.

J. In Pump House S-3, there are two pumps of which only one will work. The waste will

be delivered to splitter box-2 from where sludge recirculated to aeration tank. The

surplus sludge is transferred to sludge drying beds by gravity

flow.

K. Under normal operation, flow from guard pond will be transferred to Clear Water

Pond.

Oil Collecting System:

Oil skimmed off from surge ponds, TPI, API separator, CTBD oil separator, VOC tanks will

flow by gravity to slop oil sump S-4. One pump is in use, one is standby and the oil is

delivered to slop oil tank. It is expected that pump will run continuously in every shift.

Sludge Collection System:

The CTBD oil separator will have to be desludged once in every shift for about 10 minutes. It

is necessary to ascertain by visual inspection, how long this valve will be required to be kept

open so that only oily sludge is removed.

In addition, the sludge collected from the API separator, DAF section also flow by gravity to

sludge pump S-5. This will take place with periodical opening of sludge valve. There are two

pumps provided in this pump house. One will work normally. The anticipated working time





is 10-20 minutes per shift. This sludge will be pumped to sludge lagoon. TPI bottom sludge

also collected and transferred to sludge lagoon by sump and pumps near TPI.

There is a oily sludge lagoon of 4000 M3 Capacity. The sludges dry to a separable consistency

and is then to be manually removed. The only operation required is to open valve on sludge

lagoon depending on which is ready to accept the sludge. The melting oil from the sludge is

collected by skimmer and transferred slop oil sump S4.

Surge Pond No. 1: To hold the incoming waste coming in surges and varying rates of

flow/load and to release at a fixed rate of flow 120 M3/hr for further treatment.

Surge Pond No. 2: To skimmed oil carryover from TPI, Capacity 6000 M3

API Oil Separator: To remove free floating oil from the waste water. Free floating oil is to

be skimmed from the surface without disturbing the channel contents which might result in

emulsification.

The object is achieved by the gentle pushing of the concentrated oil surface with the

mechanism moving at a maximum permissible speed of 0.9 M/minute to effect remove of

oil globules of average dia 0.015 cm (Sp. Gr. 0.9) as per API standards.

Presently API separator is not in line after commissioning of Refinery Expansion Section.

However the separator is taken in line during maintenance of DAF section and

emergencies.

pH Adjustment Tank:

i) To correct the pH of the waste to the optimum level required for subsequent

biological treatment as and when required.

ii) To convert the sulphites to sulphates by providing oxygen.

iii)

Process Description:

During the detention period in the tank, the waste water is dosed with a predetermined

quantity of sulphuric acid to adjust the pH to the range of 7.5 to 8 to facilitate biological

treatment. In case the pH falls below 7 due to stripping of sulphites, acid addition has to

Be adjusted to raise it to the above range. By experience operator shall know that if pH

depression takes place due to sulphites oxidation. Consequently, acid feed quantity is

adjusted accordingly.

Presently acid dosing is suspended due to getting desired quality of effluents at inlet of

treatment section where acid neutralization is not required.





Bio-filter (Trickling filter): To remove to the extent of 70%, the organic load, viz. BOD,

Phenols, all sulphides of waste water and also oil to the limits tolerable for the subsequent

activated sludge process.

Brief Description of Process:

The above objective is achieved by passing the waste through the bio filter. The mechanism

spreads the waste uniformly all over the surface of the media at a more or less uniform rate.

The discharge action, viz. in the form of sheets of water from the spreader plates will expose

the waste to the atmospheric oxygen.

The waste then passed over the biological film formed on the filter media. The organisms in

the film will substantially reduce the load passing through. The waste is further subject to

oxygenation by exposure to the free oxygen available in the air pockets in the media.

Loading Data:

Phenol loading 18 lbs/1000 cft/day

Organic load removal 70% of incoming organic load

Efficiency

Recirculation ratio 1:2:5

Aeration Tank: Reduction of biochemical oxygen demand left over after degradation in bio

filter and also reduction of suspended colloidal solids.

Clarifier: The settle and remove all suspended matters in the flow as well as the floating

scum.

Brief Description of Process: On account of the detention of the waste water in the tank for

a period of time, the sludge particles will settle at the bottom on the floor and are swept

continuously to a central pocket by the revolving scrapper arm. The sludge is then drawn off

from the sludge pocket.

The lighter suspended matter called the scum, floats at the top of water. This is skimmed

mechanically and discharged continuously into a scum box. The clean effluent flows over a

circular weir readily into an outer launder running along side the tank wall.

Guard Ponds: For holding the treated effluent for quality checking before the final disposal.

Process: The treated effluent is delivered to guard pond from final clarifier. Duplicate ponds

provision helps in all owing enough time for final quality check before final disposal. The

treated effluent delivery is from top while exit is from bottom. The total storage capacity

available is 3600 M3/30 hrs detention.

Receiving Sump: A receiving sump of 5.63 M3 (3.0 M * 3.5 M *.536 M) capacity has been

provided. For a normal flow of 120 M3/hr. detentions time is about 2.8 M.





Delivery channel from screw pumps is connected to distribution chamber of surge ponds. A

bypass arrangement from receiving sump to nearest storm water drain is made to avoid

flooding of vast area in the event of failure of both pumps (though it is unlikely to happen

any time) or failure of high capacity pump.

Screw Pump: Two screw pumps are installed to deliver incoming dry weather process waste

water as well as total maximum wet weather flow (process waste + contaminated rain water

from paved areas/tank farm). The discharge capacities are 150 M3/hr and 500 M3/hr

Sludge Lagoon: The purposes of sludge lagoons are to store and dewater the wet sludge.

Oily sludge contains about 2 to 3 percent solids and balance water. The dewatered/dried

sludge shall be disposed of by either land filling. The sludge shall dry to a separable

consistency and is then to be manually removed. It is being assumed that minimum 50%

compaction shall take place during storage.

Supernatant at various levels could be taken out periodically, by means of portable pumps.

Skimmed oil is brought to sump S-4.

Nutrient Dosing System:

To add nutrients to the waste to obtain optimum condition for biological treatment.

Brief Description of Process:

The micro-organisms in the waste feed on the organic food to effect treatment. To sustain

the life of the micro-organism, nutrient such as Urea and DAP are added. The theoretical

ratio required are 1 P: 5 N: 100 BOD. Expected consumption of nutrients for design

flow/load is mentioned below:

Urea : 50 kg/day

DAP : 50 kg/day

Urea & DAP mixed with water in tanks through agitators and dosing rate is adjusted for

continuous dosing ,checked throughout the shift and recorded in the log book.

Specification of Chemicals (For WWTP):

Sl.No. Name of Chemical Specification

1. Polyelectrolyte Appearance: Clear, colourless liquid, pH 3-6,

Stability : Easily soluble in water

2. Ferric Alum Al2 (SO4)3 14H2O: 17% AI2O3 (Min)

3. Di ammonium Total N2 18%

Phosphate Total Phosphate as P2O5 46%

4. H2 SO4 Concentration 98%

(Sulphuric Acid)

5. Urea As per ISI 1781/1975

(Technical Grade)

N2 = 45.5%





General Description of Treatment (WWTP Petrochemicals):

Industrial waste water from Petrochemical section totaling about 40 M3/hr. (excluding

domestic waste water and contaminated rain water/Fire water run off) enters Surge Ponds

No. III. To this pond about 40 M3/hr of treated waste water is recycled from Guard Pond.

This pond is equipped with oil skimmers. Floating oil is removed from waste water in the

Surge Pond with the help of this skimmer and carried to slop oil sump. Effluent from outlet

chamber of this pond is carried by gravity to API oil separator via a Venturi Flume. To

regulate flow at 80 M3/hr from the pond motorized valves actuated by timer have been

provided. Extra waste water overflows to Surge Pond I & II which have been provided

previously. In rainy season contaminated rain water is also admitted to Surge Pond III and

excess waste water from new and old Surge Pond is to be carried to nearest storm sewer.

Flow from Venturi Flume goes to API oil separator. Floating oil is skimmed off and carried to

existing slop oil sump. Settled sludge at bottom is scrapped with the help of sludge scraper

and carried to existing oily sludge sump. Oil free waste water from API oil separator flows to

influent sump. Thickener supernatant and filtrate from sludge drying beds are also carried

to this sump. As this effluent lacks nutrient necessary for the next biological treatment,

nutrient solutions are added from existing chemical house. Total effluent from influent

sump (about 92.01 M3/hr) is pumped to one chamber of splitter box No. 1 leading to

trickling filter. This splitter box is provided to distribute trickling filter for recirculation and

partly to aeration tank. A bypass arrangement has been provided to bypass trickling filter.

Waste water in trickling filter, is treated biologically by the microbes for stabilization of the

organic matter. The waste water (average – 160 M3/hr maximum – 200 M3/hr) trickles over

stone media and flows continuously in the form of thin film over the attached growth of

microbial film on the stone media. The spraying action and the ventilation provided in the

trickling filter keep microbial film/slime in aerobic condition. The surface film or slime

sloughs off almost continuously because of flow resistance developed at the next immediate

surface of the stone media. The treated waste water from trickling filter is collected in

transfer sump from where it is pumped to approach chamber of splitter box No. 1. Part of

this flow (about 80 M3/hr) from Township and return sludge from clarifier are also admitted.

In the aeration tank the effluent is aerated to oxidize the organic matter. Microorganisms

present in the return sludge oxidize the organic matter and used it as food and form their

own cell mass. Thus micro organisms cell mass concentration continues to drop, which can

be removed by setting in next process. The aerators provided on the platform maintain the

contents in aerobic condition by maintaining adequate oxygen transfer rates and also

maintain adequate mixing of the contents. A bypass arrangement is provided to bypass this

aeration tank. Treated effluent from this aeration tank is carried to the clarifier where

sufficient detention time is given to the effluent and biological solids are allowed to settle at

bottom and collected in hopper with the help of scraper. Sludge, by

Hydrostatic pressure is carried to sludge sump. This sludge contains acclimatized micro

organisms. Part of this sludge is pumped back to aeration tank to keep MLSS concentration

at 4000mg/l there. Excess sludge is pumped to sludge thickener. Splitter box No. 2 is





provided for the distribution of the sludge. A bypass line of oily sludge rising main and

excess bio-sludge line from splitter box of existing plant is also admitted to chamber leading

sludge to sludge thickener. Supernatant from sludge thickener is carried back to influent

sump and thickened sludge is carried to thickened sludge sump from where it is pumped to

sludge drying beds and, if required, to existing sludge lagoon. Filtrate from sludge drying

beds is carried to influent sump.

Clear effluent from clarifier is carried by gravity to hay filter where traces of oils are

removed. Effluent from hay filter flows to Guard Ponds, and effluent from guard pond flows

to guard pond sump. Effluent from existing guard is also, if necessary admitted to this sump.

40 3/hr/hr of treated effluent is recycled by pumping to Surge Pond III and effluent in excess

is pumped to existing polishing pond. Existing chemical house provided for refinery effluent

treatment plant is used to prepare chemical solution and to feed the chemicals nutrient to

this treatment plant. The flow measuring facilitie4s are provided at important location to

measure flow of liquid, sludge and chemical solution.

The final effluent from the plant shall have following characteristics as envisaged in the

consent document of Assam State Pollution Control Board.

1. pH 6.0-8.5

2. Phenol 0.35 mg/l

3. BOD3 day 27oC 15 mg/l

4. Sulphide 0.5 mg/l


6. Suspended Solids 20 mg/l

7. COD 125 mg/l

8. Cyanide 0.2 mg/l\

9. Chromium 2 mg/l

10. Fluoride 15 mg/l

Surge Pond III and its Sump: The surge ponds are provided for storing effluent and to

discharge it at a constant rate.

.

Surge Pond Sump & Pump:: To discharge effluent to API and down stream section at

constant rate.

API Oil Separator : This unit is provided to remove the free floating oil from waste water.

Process:

The process employed here is in line with the practice of American Petroleum Institute who

has widely developed such measures for liquid oil separation.

Free floating oil is to be separated from waste water under quiescent condition which is

offered by API separator type units. The separation of free oil is based on the theory of

gravity separation. The units are designed for oil of specific gravity 0.92 and that of waste

water as 0.995 at operating temperature of 50oC. The average dia of oil globule to be





removed is assumed as 0.015 cm and absolute viscosity of 0.01 centipoises. Pre-separator

channel is provided to reduce the turbulence of water before it is allowed to flow through

the separator channel and the waste water will pass through the pipe diffusions inlet of the

API separator, which will increase the velocity of the water and as a result of this the oil

globules will get separated from the waste water and rise to the surface which are

subsequently removed by the API Oil Skimming mechanism.





Trickling Filter: This unit is provided to remove 70% of incoming BOD to trickling filter.

Process :

The trickling filter contains broken stone media covered with micro organism (Zoo Leal film).

Waste water is applied on the medium at a controlled rate (Trickled), causing intimate

contact between waste, micro organisms and oxygen, resulting in chemical, physical and

biological changes (Purification) to the applied waste water. The micro organisms absorb the

organic matter as food. The spraying action through distribution arm and ventilation

provided keep the slime layer thus formed in aerobic conditions. When the slime layer

becomes thick inner surface becomes anaerobic and the slime layer gets sloughed from the

media surface. This is more or less a continuous process. For high rate operation the waste

water is recirculated.

Aeration Object of this biological treatment is to oxidize organic matter contributing Bio-

chemical oxygen demand (BOD). For this purpose waste water is aerated with the help of

aerators.

Process :

Sewage from distribution box (135 M3/hr) and effluent from splitter box 1 (80 M3/hr) are

fed to the inlet of aeration bank. In addition to this, return sludge from clarifier is admitted

to the inlet of the aeration tank. In the aeration tank the effluent is aerated to oxidize the

organic matters. Micro organisms present in the return sludge oxidize the organic matter

and use it as food and form their own cell mass. Thus micro organisms cell mass

concentration continues to drop. These cell mass can be removed by settling thus leaving

effluent free of oxygen demand.

The aerators provided on the platform maintain the contents in aerobic condition by

maintaining adequate oxygen transfer rates. They also provide adequate mixing of the

contents and thereby contents do not settle on the floor of the tank. The flow from outlet

launder goes to the clarifier. Bypass arrangement has been provided to bypass aeration

Clarifier: This unit is provided for removing the biological settle able solids formed in

process.

Process :

The clarifier is continuous flow circular basin. The waste water from Aeration Tank is

admitted by feed pipe to the inlet feed well at the centre of circular RCC tank. Feed well

deflects the incoming effluent downward thus avoiding the tendency of the liquid to short

circuit and directly traverse towards the overflow weir. Gravity is the principal force causing

the solids to settle down. Factors affecting the settling are surface loading rate, period of

retention, size of particles, concentration of suspended particles temperature, viscosity of

waste water, etc.





The mass known as biological sludge settles down and with the help of scraper mechanism

is collected at the bottom of the tank. The valve on sludge line is opened to discharge it to

sludge sump from where about 66% is pumped back to aeration tank and excess sludge is

pumped to sludge thickener.

Guard Pond : The guard ponds are provided to collect the treated waste water.

Process

Inlet chamber of guard pond receive treated effluent from hay filter and is discharged into

the guard pond sump from where about 40 M3/hr. is recirculated by pumping to surge

pond/ISP and remaining effluent is pumped to polishing/clear water pond.

Sludge Thickener: This unit is provided for reducing the sludge volume to be disposed off

into the sludge drying beds/sludge lagoon.

Process :

The process for sludge thickening is more or less similar to that of clarifier. The sludge

thickening mechanism fitted into RCC tank serves to concentrate sludge from 1% to 4$ and

pushes the sludge to centre pocket from where it can be carried to thickened sludge sump

for pumping into sludge drying beds/existing lagoon. Supernatant is carried to ISP.

Sludge Drying Beds: Sludge drying beds are provided to dewater the biological sludge

containing about 95% of water. The dewatered sludge, in the form of dried cake, is to be

disposed off.

Process:

Sludge is spread on the filter media containing gravel and sand. Simple physical straining of

solid takes place. Water is partially lost by seepage through sand layer and partially by

evaporation at ambient temperature. At bottom of filter media, collection system

comprising of open jointed pipe is provided to collect the filtrate. The entire system is

enclosed by brick masonry. Filtrate is carried to influent sump.

Refer the ETP process flow diagram below:









ANNEXURE IX

TERTIARY TREATMENT PLAN





Tertiary Treatment Plant :

Treatment Philosophy:

The treatment philosophy, contemplated for the Tertiary Treatment Plant, consists of

chemical treatment by conventional lime soda process for the removal of hardness and the

silica, will be accomplished by treating with dolomite lime which contains 35-40% of

magnesium as Mgo. This process, by default, will also reduce the residual BOD of the

treated water to some extent. Turbidity removal will be achieved during the process of

filtration in pressure sand filter. The removal of organics & traces of hydrocarbons will be

achieved by adsorption with Granular Activated Carbon Filter followed by chlorination.

Chlorination will control the biological growth in addition to providing disinfection.

Influent & Effluent Water Quality (Design Basis) :

The design basis for the above said tertiary treatment plant is presented in Table 1.0 & Table

2.0.

Design Basis for Influent Water:

Flow Rate (M3/hr) 400

pH 7.5 – 8.5

Oil & Grease (mg/1) 0.0

BOD5 (mg/l) 40.0

TSS (mg/l) 50.0

TDS (mg/l) 300-450

SiO2 (mg/l) 40.0

Total Hardness (mg/l) 190

Carbonate Hardness (mg/l) 30

Non-Carbonate Hardness (mg/l) 160

- Ca Hardness (mg/l) 118

- Mg Hardness (mg/l) 42

Table = 2.0

Cooling Water Make Up Characteristics

pH (mg/l) 6.5 – 7.0

Oil & Grease (mg/l) Less than 3.0

BOD5 (mg/l) less than 15.0

TSS (mg/l) less than 10.0

SiO2 (mg/l) 20.0

Total Hardness (mg/l) 30

- Carbonate (mg/l) 10

- Non-carbonate (mg/l) 20

Process Write Up :

The scheme contemplated for the tertiary treatment of combined secondary treated

effluent from refinery & petrochemical ETPs basically consists of the following five sections:

Section-I: Water softening & removal of silica in a sludge blanket clarifier.

Section-II : Removal of carryover suspended solids, residual BOD & oil, in a series of

operation in pressure sand filter & Granular Activated Carbon Filter.





Section-III : Chlorine treatment of the filtered water to remove the biological growth in the

water.

Section-IV : Sludge Management Section.

Section-V : Chemical dosing section.

Section-I :

Section-I of the treatment scheme comprises of Flash Mixer (100-T-001) & sludge blanket

clarifier (100-CL-001). Water is withdrawn from the BL of the clear water pond.

There are three numbers of pumps (100-P-001A/B/C), each of 200 M3/hr capacities. Suction

side of these pumps will be floated. Only two pumps shall be in operation & third one will

act as standby. The water from clear water pond is pumped to Flash mixer (100-T-001).

Chemicals like 10% sodium carbonate & 10% lime solution are dosed to the Flash Mixer.

Retention time of 3.0 min is provided in the flash mixer (100-T-001).

The thoroughly mixed water flows to the sludge blanket clarifier by gravity through a central

feed pipe line. There are three zones in sludge blanket clarifier, namely, Flocculation zone,

Reaction zone & Clear water zone. Water first comes, to the Flocculation zone.

Polyelectrolyte solution of 0.5% strength is dosed in the flocculation zone, from where the

flocculated water enters the reaction zone.

Reaction zone consist of a blanket formed by reactants & products as a result of the cold

lime soda reactions. This reaction zone is dynamic in nature. It keeps on renewing due to

settling of precipitates formed in the reaction zone.

The clarified water finds its way to the pH adjustment tank. Chemical sludge generated due

to the formation of precipitates of carbonates & silicates, is collected from the bottom of

the clarifier.

Section-II :

Section-II basically consist of pH adjustment tank (100-T-002) followed by series of

operation in Pressure Sand Filter (100-FPS-001/002/003/004/005). Clarifier water from

Sludge Blanket clarifier is at a Ph of 10.0-11.0. The pH of the water is brought down to 7.5 by

sulphuric acid addition. The solution is provided detention time of about 15 min for proper

pH adjustment.

A pH indicator & controller is provided in the tank. Dosing of sulphuric acid shall be

governed by the pH difference in the set value and measured value of pH indicator.

After pH adjustment, water is pumped to the pressure sand filter (100-FPS-

001/002/003/004/005) for removal of suspended solids & turbidity. There are three

numbers of pumps (two operating and one standby), each of 200 M3/hr rated capacity. The

pressure sand filters are designed for the flow rate of 100 M3/hr.

There are also differential pressure measuring device & whenever the desired differential

set pressure is reached it would give alarm. The standby unit shall be ready for operating.

Filter back wash is done by air according for 2-3 min. & then washing it with treated water.

One set of high capacity purpose of back washing. The filtered water is collected in a

primary storage tank (100-T-003).





Section-III:

This section deals with the chlorination of filtered water. The vacuum type of chlorination

system has been adopted. Pump (100-P-006A/B) has been provided in the chlorination

system which pumps the water to the ejector from the storage tank. In the primary storage

tank chlorine diffuser are provided wherein the chlorine solution will be mixed with the

filtered water. The storage tank is provided with half an hour detention time. At the outlet

of storage tank two set of pumps (100-P-003A/B), (100-P-004A/B/C) are provided one for

back washing of filters & another is for transfer of the tertiary treated water for cooling

tower make up.

Section-IV:

Section-IV basically deals with the sludge management. The only source, from where

chemical sludge is generated, is the sludge blanket clarifier bottom. This sludge is received

in a sump (100-S-001). There are two No. of pumps100-P-005A/B which transfers the

chemical sludge to the existing sludge drying beds.

Section-V :

Section-V is chemical preparation & dosing section. Storage facility of chemicals is provided

in chemical house on the ground floor. There is one sulphuric acid storage tank (100-T-001)

where bulk H2SOP4 of 98% strength is stored outside the chemical house. Two Nos of

transfer pumps (100-P-007A/B) are provided in which one is standby. There are two no

(100-T-006A/B) of sulphuric acid preparation tanks on the first floor. Two pumps (100-P-

008A/B) transfer the 10% solution to the pH adjustment tank.

There are also alum solution preparation tank (100-T-007A/B, 100-T-010A/B),

polyelectrolyte dosing tanks (100-T-008A/B) & sodium carbonate preparation tank (100-P-

009A/B) on the first floor of the chemical house. There is one main water header through

which service water is supplied to overhead tank which is connected to dosing tanks. All the

dosing tanks are fitted with level gauge, overflow/underflow drain & all necessary dosing

facilities. In all the tanks metering pumps (100-P-009A/B), (100-P-010A/B), (100-P-011A/B)

& (100-P-012A/B) are also provided with necessary instruments & fittings.

Presently sodium carbonate and sulphuric acid dosing are suspended.

Chemical consumption:

Ferric alum and Polyelectrolyte are mixed with water in separate tanks by agitators. Dosing

rate is adjusted for continuous dosing and checked throughout the shift and recorded in the

log book. Chlorine is dosed in primary storage tank by chlorinator.

Chemical Consumption

Ferric alum 40 kg/day

Polyelectrolyte 2 kg/day

Chlorine 1 kg/hr





ANNEXURE X

Environmental Compliances





ENVIRONMENTAL CLEARANCE COPY

















Half Yearly Report for the period of 1st

October 2014 to 31st

March 2015

for “Refinery Expansion Project”





.















Assam


ANNERURE XI (Organogram of HSE Personnels)

Documents

Environmental Impact Assessment (EIA) - Pollution Control