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EMERGENCY RESPONSE & DISASTER MANAGEMENT PLAN

KKBMPL (Phase 1), GAIL (India) Limited, Kochi

Revision : 0 Date : 12.12.2012 EMERGENCY RESPONSE & DISASTER MANAGEMENT PLAN C-10/1

CChhaapptteerr –– 1100

PPrree EEmmeerrggeennccyy PPllaannnniinngg

(As per Clause No 10.0 of PNGRB regulations)




Pre- Emergency Planning (As per Clause No. 10)

Hazard Identification (As per Clause No. 10.1):

KKBMPL (Phase 1), GAIL (India) Limited, Kochi GAIL (India) Limited, is involved in

transportation of Natural Gas through cross country pipeline. The major hazard for our industry is

Natural Gas which is highly inflammable in nature.

Natural gas is a mixture of hydrocarbon gases having very low boiling point. Methane the

first member of paraffin series makes up for approximately 80% of the natural gas. Ethane,

Propane, Butane and higher hydrocarbons up to Heptanes are also present.

Natural gas has no distinct odor. Its important properties are as under:

Calorific value 8600 KCa/Nm3

Molecular weight 16.3

Explosive Range 5.3 to 14%

Auto-ignition Temperature 535 Dego C

TLV 3 Mg/m3

The degree of fire and explosion hazards of natural gas is high, mainly for the following reasons:

• Extremely low boiling point.

• Poor visibility of ignitable mixture and high burning velocity that can injure instantly anyone

coming into contact with it on account of high calorific value.

• Highly inflammable.

• Under atmospheric pressure and low concentration, natural gas is not toxic for human being. Its

TLV is 3 Mg/M3. However, at high concentrations, hydrocarbon gases displace Oxygen

causing asphyxia.

• In case of inhalation if concentration is high, it will displace oxygen in air. Too little Oxygen

can increase breathing and pulse ratio, disturb muscle coordination, emotional aspect, fatigue,

nausea, vomiting, respiratory collapse, even death.




The identified potential On-Site and Off-Site hazards are duly classified in Chapter 6 under Clause

6.0 of Regulation.

The Material Data Safety Sheet of Natural Gas having the information on physical,

chemical & toxicological properties and their mitigation methods in prescribed format attached as

Annexure I.

GAIL (India) Limited, is handling huge quantity of flammable gas and connected through

the gas pipeline network at Kochi. Objective of this study is to make an assessment of:-

1. The risk to the health and safety of employees to which they are exposed to whilst they are at

work and

2. The risk to the health and safety of persons who are not employees arising out of or in

connection with the conduct by the employees of the undertaking.

The ERDMP study focused upon:

� Critical deviations and points in process may be the source of any undesirable event.

� To identify the potential hazards and operating difficulties posed by any possible deviation by

carrying out Hazard& Operability Study.

� To assess the consequence of identified failure scenarios for determination of hazard distances

and impact zones.

� To assess the risk posed by the facilities to the surroundings.

� To suggest measures to reduce hazards and risks.

This study included localized incidents that may lead to onsite damages as well as all the

incidents, which would cause off-site causalities. The most probable hazards have been identified

and consequence analysis was done.




Various Layers of Protection in the Pipeline and Associated Facilities:

In the HAZOP study of KKBMPL (Phase 1), GAIL (India) Limited, Kochi, layer of

Protection Analysis (LOPA) approach has been utilized in ranking risk.

HAZOP study deals with the identification of hazards due to process parameter deviations.

When a failure occurs due to deviations, it may take the process outside of its normal operating

ranges. In general, there are several layers of protection measures in a plant in response to a

process deviation. The basic process controls, alarms, safety valves, operator supervision etc. are

the typical protection measures against any harmful consequences due to deviation of process

parameters as shown below:

� Process equipments designed for process operating limits.

� Basic process controls, alarms and operators are adjusted to process deviations.

� Presence of Critical Alarms along with Speedy Response of Operators.

� Safety Interlock System/Emergency Shut Down at operating limits.

� Relief Systems that activate at equipment design limits.

� Mitigation systems that contain the effects of incident.

� Plant emergency response to control the effects of incidents.

(On-site Control Arrangement).

� Emergency response to protect the public from the effects of an incident.

(Offsite Control Arrangement).

The hazard of pipeline handling Natural Gas is the fire and explosion due to release of gas. Even a

hairline fracture in pipeline would release gas. In case of rupture or major leak in buried pipeline

the escaping gas may lead to a fire/explosion hazard.

The following Operations & Installations have been considered during HAZOP study of Gas

pipeline:

1. Receiving terminal

2. Intermediate Pigging Station

3. Sectionalizing Valve Station

4. Customer Terminals.

(Refer Hazop Study Report of M/s MECON India Ltd. In the year 2011)




Risk Analysis and Risk Assessment (As per Clause No. 10.2):

The causes of pipeline failure are elaborated as below:

The initial cause of the incident

1. External interference

• The activity having caused the incident (e.g. digging, piling, ground works)

• The equipment involved in the incident (e.g. anchor, bulldozer, excavator, plough)

• The installed protective measures (e.g. casing, sleeves)

2. Corrosion

• The location (external, internal or unknown)

• The corrosion type (galvanic, pitting, stress corrosion cracking “SCC” or unknown)

3. Construction defect/material failure

• The type of defect (construction or material)

• The defect details (hard spot, lamination, material, field weld or unknown)

• The pipeline type (straight, field bend, factory bend)

4. Hot tap made by error

5. Ground movement

6. The type of ground movement (dike break, erosion, flood, landslide, mining, river or

unknown).

7. Other and unknown

• The sub-causes out of category such as design error, lightning, maintenance

• Hazards due to release is depends upon occurrence of ignition or non-ignition

The pipeline handles Natural Gas, which is highly inflammable and mainly possess fire &

explosion hazard due to accidental release. The pipelines are laid underground and all precautions

have been taken for its integrity from design stage up to installation as well as during

commissioning and operation. Safeguards have been taken against corrosion by using cathodic

protection as well as by the application of the other protective coating on the external surfaces.

Hence, chances of corrosion are rare.




However, in the event of release of the gas from its containment due to any other reason

there is risk of fire & explosion. Risk Assessment deals with various failure cases (incredible,

credible as well as less credible) leading to various hazard scenarios. Consequence analysis is

basically a quantitative study of hazard due to various failure scenarios to determine the possible

magnitude of damage effects and to determine the distance up to which damage may be affected.

The reason and purpose of consequence analysis are manifold like:

• For computation of risk

• For formulating safe design criteria and protection system

• For evaluating damage and protective measures necessary for saving other properties

• To ascertain damage potential to public and evolve protective measures

• For formulating effective Disaster Management Plan.

Modes of Failure

There are various potential sources of large/small leakage. The leakage may be in the form

of gasket failure in a flanged joint or snapping of small dia. pipeline connected with main line,

leakage due to corrosion, pipe bursting due to excess pressure, weld failure and other sources of

leakage. Some typical modes of failure and their possible caused are discussed:

Loss of Containment Probable Cause Remarks

Flange/Gasket Failure Incorrect gasket, Incorrect

installation

Careful attention to be taken during

selection of gasket & installation.

Weld failure

• Incorrect use of welding material

and weld procedure

• Lack of inspection during welding

• Incorrect use of design code.

Welding to be done by certified

welder with proper quality of welding

rod under strict inspection with stage

wise checking and acceptance after

final radiography. Proper code to be

followed for welding.

Pipe over stress

causing fracture

• Error in stress analysis, improper

pipe material.

• Inappropriate design code and

Pipe stress may also cause flange

leakage unless there exist a

combination of causes. Stress




Identified Loss Scenarios:

Based on the hazard identification and common modes of failure the following cases of

leakage of gas have been considered for the purpose of risk analysis in this report:

� Pinhole / Crack (5 mm)

� Leakage through a hole greater than 20 mm & less than 50 mm

� Instrument tapping failure

� Gasket failure

incorrect support, lack of

inspection during inspection.

• Natural Disaster

analysis of piping and proper support

selection to be done during design,

during erection, strict inspection to be

ensured.

Over pressurization of

pipe causing rapture

• Incorrect setting of SRV and pop

off valve pressures.

• Incorrect SRV/Pop off valve size.

Careful attention is needed for

selection of SRV/Pop off valve size.

Setting of SRVs and pop off valves to

be checked before installation as well

as at regular interval.

Failure of pipe due to

corrosion or erosion H2S, water and soil corrosion

Proper care should be taken against

internal as well as external corrosion

and monitoring of condition of

pipeline to be done regularly.

Leaking valve to

atmosphere

Gland failure packing failure

spindle/plug cock flow out.

Leakage to be rectified at shortest

possible time.

Valve body failure Catastrophic valve body/bonnet

failure Failure to be rectified immediately.

Instrument/connection

failure

Bourdon tube failure, failure of other

instrument connection etc. Failure to be rectified immediately.

Overpressure Inadequate relief, fire impingement Failure to be rectified immediately.

And other suitable action to be taken.

Breakage of Pipelines Natural Disater

Pumping should stop immediately,

prompt mobilization of resources for

emergency mitigation




� Release of gas during depressurization

� 20% Cross Sectional Area of pipeline failure

Damage Criteria:

The damage effect of all such failures mentioned above is mainly due to thermal

radiation/explosion due to ignition of gas within the flammability limit. Natural Gas released over

ground accidentally due to any reason will normally be from a gasket or from portion of the

pipeline. In case of leakage from buried portion of the line, the leaking gas will come up through

the ground because of porosity of the soil or by throwing away the covered soil. The gas coming

up may get ignited if it comes in contact with an ignition source forming flash/ jet fire. Thermal

radiation due to flash fire may cause various degrees of burn on human bodies. Also, its effect on

inanimate objects (e.g equipment, piping, building etc) is also there and needs to be evaluated. The

damage effects with respect to thermal radiation intensity are elaborated below:

Physical Impact of Heat Radiation

Heat Radiation Level (Kw / m2) Duration (Secs) Effect

2.5 65 Blistering Starts

5 25 Do

8 13.5 Do

11 8.5 Do

18 4.5 Do

22 3 Do

10.2 45.2 Lethal ( 1%)

33.1 10.1 Do

146 1.43 Do

Effects of Radiation (Source: World Bank)




Damage Effects Due to Over Pressure

Over Pressure

(Milibar) Type of Damage

10 – 15 Typical window glass breakage

35 – 75 Windows shattered, Plaster cracked, Minor damage to

some building

70 – 100 Personnel knocked down

75 -125 Panels of sheet metal buckled

125 -200 Failure of walls constructed of concrete blocks or

cinder blocks

200 - 300 Oil storage tank ruptured

400 - 600 RCC Structure severely damaged

350 - 1000 Ear drum rupture

2000 - 5000 Lung damage

7000 - 10,000 Lethal

Risk Ranking:

The consequences of various causes has been examined with the help of simple Risk

Matrix involving Severity, Likelihood and the risk ranking in each case. These rankings are

qualitatively done using a simple scale from 1 to 5 for both severity and likelihood. The various

combinations of severity, likelihood and risk are defined as Risk Matrix or Risk Grid.

Table- A

Grading scheme adopted for severity of Hazards

Sl.

No. Rank Grade Description

1. Very low 1 No fatality, no injury, only material loss.

2. Low 2 No fatality, non-reportable injury, material loss, may or

may not be equipment damage.

3. Medium 3 No fatality, minor injury, material loss, equipment damage.

4. High 4 Single fatality.

5. Very high 5 Multiple fatality.




Table- B

Grading scheme adopted for probability of Occurrence

Sl. No. Rank Grade Description

1. Very low 1 Once in 10 years

2. Low 2 Once in 5 years

3. Medium 3 Once in 3 years

4. High 4 Once in an years

5. Very high 5 Once in 6 month

Note: The probability of occurrence is categorized based on chances of occurrence accidents due to deviation in

performing the normal activity.

In addition, prioritization of all the risks to identify the significant risks based on the above

risk ranking scheme & matrix is given in the tables- C & D:

Table- C

Risk Ranking Scheme

Sl. No. Rank Description

1. H High

2. M Medium

3. L Low

Table- D

Risk Ranking Matrix

PR

OB

AB

ILIT

Y

5 L M M H H

4 L M M H H

3 L L M H H

2 L L L M H

1 L L L M H

1 2 3 4 5

SEVERITY




Residual Risk Ranking: After ranking of all OHS Risks based on the above grading and ranking

criteria, a review on adequacy of existing control measures were carried out to find out tolerable

risks and re-ranked them as residual risks using the ranking scheme High (H), Medium (M), Low

(L).

Hazard Identification sheet is attached as Checklist 1

Meteorological Conditions

(a) Rainfall & Temperature

The climate of the place is moderate. The place is having annual average rainfall of 834.1

mm and average temperature in summer is between 29-380C and in winter is 12-23

0C.

However, in summer the maximum temperature may go as high as 430C during day

and in winter minimum temperature may fall down to 30C during night.

(b) Wind Direction and Wind Velocity

During winter wind flows mainly from North-Eastern and Eastern directions. But in summer

wind flows mainly from North-Western and Western directions.

Wind speed remains low in winter around 5.3 Km/hr and in summer the average wind speed

is about 14.6 Km/hr. The wind speed varies from 6.3 Km/hr to 7.8 Km/hr.




METEOROLOGICAL DATA

STATION : KOCHI (Cochin)

LATITUDE : 09°57' N

LOCATION :

Situated at the Naval Base, Cochin; exposure good. LONGITUDE : 76°16' E

Month

Air Temperature

Relative Humidity

Vapour Pressure

Rainfall Mean Wind Speed

CLOUD

Daily Max.

Daily Min.

Highest in the Month

Lowest in the Month

Monthly Total

No. of Rainy Days

Heaviest Fall in 24 Hrs.

Date &

Year

No. of days with cloud Amount (All Clouds) O K T A S

No. of days with low cloud amount O K T A S

ºC ºC ºC ºC % hPa mm mm Kmph 0 T-2

3-5

6-7

8 0 T-2

3-5

6-7

8 FOG 8

January 31.4 22.1 33.1 19.3 73 23.0

21.9 1.0 71.2 14

6.3 3 11 11 6 0 11 17 3 0 0 0

61 24.7 1967 5 9 10 6 1 13 15 3 0 0 0

February 31.8 23.4 33.3 20.7 76 25.4

22.9 1.4 85.1 08

6.7 2 10 10 5 1 7 17 4 0 0 0

64 26.4 1952 3 10 8 6 1 11 13 4 0 0 0

March 32.4 25.0 33.8 22.6 75 28.6

35.3 2.3 90.6 31

7.8 3 12 11 5 0 5 21 5 0 0 0

67 28.9 1970 2 11 10 7 1 5 17 8 1 0 0

April 32.7 25.4 33.9 22.5 77 30.4

124.0 7.5 177.0 29

7.7 0 5 12 11 2 2 18 9 1 0 0

71 30.7 1956 1 2 9 15 3 1 7 18 4 0 0

May 31.7 25.3 33.5 22.6 82 30.8

395.7 12.9 209.1 25

7.8 0 2 8 15 6 0 11 15 5 0 0

75 31.0 1965 0 1 7 17 6 0 6 18 7 0 0




Causes of Disaster (As per Clause No. 10.3):

Likely causes which can lead to emergencies and thus cause damage to plant personnel,

equipment, population at large and environment are tabulated below.

(Refer Hazop Study Report of M/s MECON India Ltd. In the year 2011)

Man made Natural Calamities Extraneous

�� Heavy Leakage

�� Fire

�� Explosion

�� Failure of Critical Control

system

�� Design deficiency

�� Unsafe acts

�� In-adequate maintenance

�� Flood

�� Earth Quake

�� Outbreak of Disease

�� Excessive Rains

�� Riots / Civil Disorder

/Mob Attack

�� Terrorism

�� Sabotage

�� Bomb Threat

�� War / Hit by missiles

�� Abduction

�� Food Poisoning/

�� Water Poisoning

Failure Case Listing

The mode of approach adopted for consequence analysis is first to select the probable

failure scenarios and then to conduct consequence analysis of selected failure cases. The failure

cases selected are listed in Table.

The failure cases that are selected for study are indicated in following tables. The purpose

of this listing is to examine consequences of such failure individually or in combination. The

frequency of occurrence of failure also varies widely. Guillotine failure of pipeline of higher size

has a low frequency of occurrence.

Selected Failure Cases

SN. Event System /

section Hazard

1. Release of flammable gas,

Formation of vapour cloud

, fire, explosion

Pipeline Failure of pipeline, bursting of pipeline due to

- Corrosion

- Vibration




SN. Event System /

section Hazard

- External loading

- Operation error

- Over pressure

- Maintenance failure

- Communication failure

- Sabotage


formation of vapour cloud,

fire, explosion.

Mainline Generation of high pressure, rupture in line,

leakage due to

- Excessive casing temperature

- Excessive bearing temperature

- Seal failure

- High discharge pressure

3. Release of flammable gas ,

formation of vapour cloud,

fire, explosion.

Online Generation of high pressure, rupture in line,

leakage due to

- Excessive casing temperature

- Excessive bearing temperature

- Seal failure

- High discharge pressure

4. Fire Motor

Fire due to

- High motor bearing temperature.

- High winding temperature

- Electrical fault


fire, explosion

Valve Generation of over pressure and failure of

valve due to

- Improper operation of valve when required

- Wrong operation of valve




Dispersion and Stability Class

In calculation of effects due to release of gas dispersion of gas plays an important role as

indicated earlier. The factors, which govern dispersion, are mainly Wind Velocity, Stability Class,

Temperature as well as surface roughness. One of the characteristics of atmosphere is stability,

which plays an important role in dispersion of pollutants. Stability is essentially the extent to

which it allows vertical motion by suppressing or assisting turbulence. It is generally a function of

vertical temperature profile of the atmosphere. The stability factor directly influences the ability of

the atmosphere to disperse pollutants emitted into it from sources in the plant. In most dispersion

problems relevant atmospheric layer is the nearest to the ground. Turbulence induced by buoyancy

forces in the atmosphere is closely related to the vertical temperature profile.

Temperature of the atmospheric air normally decreases with increase in height. The rate of

decrease of temperature with height is known as the Lapse Rate. It varies from time to time and

places to place. This rate of change of temperature with height under adiabatic or neutral condition

is approximately 1oC per 100 meters. The atmosphere is said to be stable, neutral or unstable

according to the lapse rate is less than, equal or greater than dry adiabatic lapse rate i.e. 1oC per

100 meters.

Pasquill has defined six stability classes ranging from A to F

A = Extremely unstable.

B = Moderately unstable.

C = Slightly unstable.

D = Neutral.

E = Stable.

F = Highly stable.

Consequence Analysis (As per Clause No. 10.4)

In this section, accident consequence analysis to determine the consequence of a potential

major accident on the installation, the neighborhood and the environment are being discussed by

evaluating the consequence of incidence involving hazardous materials vis-a-vis LNG.

Consequence analysis also involves assessment of release quantity which is again dependent upon

chemical, handling condition, type of release, duration etc. Catastrophic flammable material



normally involves the air borne release of these materials. A potential catastrophic release of

flammable material would involve air borne release and subsequent explosion or fire i.e. a

sufficiently large fuel – air mixture within flammable mix rapidly developed and finds a source of

ignition. However LNG will be transported under pressurized condition and is expected to be

distributed to the user points in gaseous form. Accordingly possible release quantities under

pressurized conditions have been computed and presented in Figure. From the figure it can be

noticed that release rate & quantity of LNG increases as the leak size increases and ultimately

leading to a total rupture. LNG is a low explosive chemical. Therefore it necessitates a release of

substantial quantity to have a catastrophic situation. Release of this quantity of flammable vapour

in a few minutes has been used for deciding the catastrophic potential.

Computed Possible Release Quantities Under Different Conditions

Flammable releases cause harms as a results of fire or explosion. Flammable vapour cloud

resulting from rapid, release of LNG is being calculated. Since the cloud center cannot be

predicted, a conservative approach has been followed and it has been assumed that the cloud drift

towards downwind from the point of release when the danger of ignition occurs. Assuming that

the cloud would drift in any direction, the “Hazard Area” around LNG transportation pipeline has

been established by drawing a circle of radius equal to the distance, which may be affected due to

heat intensity. The possible affected areas have been computed based on the consideration of

release from leak & rupture of the pipeline of 300mm diameter and for a maximum period of 600

RELEASE RATE OF CNG THROUGH DIFFERENT DIA HOLES @ 72 Kg / Cm2

0

1

2

3

4

5

6

0 5 10 15 20 25 30

HOLE DIA IN MM

RELEASE RATE IN Kg / Sec




Second. It has been assumed that within this period any leak and rupture can be detected and

preventive steps can be taken.

The effect of overpressure due to blast effect and the effect of thermal radiation due to fire

on unprotected skin is also presented below in Tables shown below, respectively. The respective

overpressure generation and thermal radiation intensity is shown in Figures 6.2, 6.3 & 6.4.

Effect of Different Overpressure

Over Pressure

(Milibar) Type of Damage

10 – 15 Typical window glass breakage

35 – 75 Windows shattered, Plaster cracked, Minor damage to

some building

70 – 100 Personnel knocked down

75 -125 Panels of sheet metal buckled

125 -200 Failure of walls constructed of concrete blocks or

cinder blocks

200 - 300 Oil storage tank ruptured

400 - 600 RCC Structure severely damaged

350 - 1000 Ear drum rupture

2000 - 5000 Lung damage

7000 - 10,000 Lethal

Relation between Heat Radiation Intensity, Time and Effect on Man

Heat Radiation Level (Kw / m2) Duration (Secs) Effect

2.5 65 Blistering Starts

5 25 Do

8 13.5 Do

11 8.5 Do

18 4.5 Do

22 3 Do

10.2 45.2 Lethal ( 1%)

33.1 10.1 Do

146 1.43 Do



Fig. 6.2 : Flammable range for different quantities of release of LNG

Fig. 6.3: Peak Incident Pressure at Different Distance Due to Explosion of Various Quantities of

Vapour Cloud

FLAMMABLE RANGE FOR DIFFERENT RELEASE

QUANTITY

0

50

100

150

200

250

596 289 113 30.4 3.2

RELEASE QTY IN KG

DISTANCE IN M

Series1

PEAK OVERPRESSURE VS DISTANCE FOR VAPOUE EXPLOSION OF DIFFERENT QTY. OF

CNG

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

200 400 600 800 1000 1200 1400

DISTANCE IN M

OVERPRESSURE IN bar

Series1

Series2



Fig. 6.4: The Heat Radiation Intensity at Different Distances for Different Quantities of

Releases

From the above it can be noticed that only in case of total rupture of pipelines there is a

possibility of release of maximum quantity of LNG. If there is any fire involving this released

quantity then only the thermal radiation intensity will be maximum. Comparison of appreciable

thermal radiation intensity will persist in an area covering a radius of about 600 m. The

overpressure generation for any explosion for this quantity of release will not be of any

appreciable affect at this distance.

Risk & Consequences Analysis

Risk is defined as a measure of human injury, environmental damage or economic loss in

terms of both the incident likelihood and the magnitude of the loss or injury. Risk analysis

deals with the development of a quantitative or qualitative estimate of risk based on

HEAT RADIATION FROM EXPLOSION FOR RELEASE OF DIFFERENT QUANTITY OF CNG

0

500

1000

1500

2000

2500

0 20 40 60 80 100 120 140 160

THERMAL LOAD KW/m²

DISTANCE IN M.

Release 596 Kg.

Release 50800 Kg




engineering evaluation and mathematical techniques for combining estimates of incident

consequences and frequencies. Thus the analysis of risk of any activity involving hazardous

materials consists of the two elements:

(i) Consequences of accident and (ii) Probability that this consequence will occur.It implies

that:-

Risk = Probability x Consequence

Any given accident may have several consequences such as loss of life, injury etc. The

probability of an accident is normally expressed as probability per year, for example, 0.02 per

year, which means that this type of accident statistically will occur, on the average, every

1/0.02 = 50 years.

Risk acceptability criteria

There is no acceptable risk criterion in Indian regulation. Bureau of Indian Standard

(IS:15656) prepared an Indian code of practice on consequence and risk analysis in line with

HSE, UK and VROM, The Netherlands. Following this standard, in the present analysis, it has

been assumed that maximum tolerable risk per event-year is 1x10-6. However, ERDMP document

clearly indicated the IRPA, as follows:




For the assessment of `Individual Risk' due to LNG PIPELINE the following has been

taken into considerations:

a) The individual risk has been calculated as cumulative effect of all the scenario mentioned for

selected failure case as listed in Table No. 3.4 for 2B, 3D, 5D (Day condition) and 2F, 3D, 5D

(Night condition) where 2B, 2F, 3D & 5D are wind speed of 2 m/sec & unstable stability

class, wind speed of 2 m/sec and stable stability class, wind speed of 3 m/sec and neutral

stability class & wind speed of 5 m/sec and neutral stability class atmospheric conditions

respectively.

b) Probability of wind directions has been taken from IMD data.

c) No mitigation factors such as shelters, escape etc. are considered which will result in

conservative risk estimation.

d) During risk assessment population data and source of ignition has been considered.

The Iso-Risk Contours for the Take off point, S/V stations and metering skids are presented. The

acceptable Risk Contour of 10-6 /year remains confined within premises of metering skids.

Societal risk in the form of F/N curves are indicating that the risk is well within acceptable limit

and are shown in drawing.

The various impact zones of jet fire are the maximum hazard distances and will come down

further with lapse of time due to depressurization of line/system.

Effect on Flora and Fauna

Under atmospheric pressure and low concentration Natural gas is non toxic,its TLV is

3mg/m3.However it will replace oxygen causing asphyxiation.Since KKBMPL pipeline deals with

Natural gas in gaseous state,its effect on flora and fauna will be minimal.

Hazards due to Natural Perils

Risk Mitigation Recommendations

Recommendations:

KKBMPL Natural Gas Pipelines is certified with ISO 9001, ISO 14001 & OHSAS 18001.

Operation & Maintenance procedures are well established as per National & International

Standards like OISD, ASME, API etc. and followed genuinely. However, following some of the




recommendations are given below which requires to be more thoughtful during the Operation &

Maintenance to further maintain the health condition of pipeline system to avoid any emergency

situations.

Cathodic Protection

1. Failure due to corrosion in pipeline is a leading cause for an incident. It is very important to

establish the procedure for monitoring of internal & external corrosion of pipeline and its

effective implementation. Prevention against corrosion by ensuring effectual cathodic

protection system should be followed in line with requirement of OISD 226 & PNGRB

regulation.

2. Internal corrosion of the pipeline already been monitored through Intelligent Pigging of

pipeline.

3. Monitoring of corrosion through corrosion coupons should be ensured.

4. Painting of above ground pipeline to be ensured in time bound manner to protect the

pipeline against corrosion.

Line Patrolling

Line patrolling is important to ensure the visual inspection of pipeline along with entire ROU,

encroachments, washouts & others aspects etc. Pipeline patrolling should be ensured as per

schedule and action must be taken on any observation recorded during the pipeline patrolling.

Others:

1. Operatibility of Leak Detection System at above ground installation must be ensured.

SCADA, so that necessary action can be initiated for closure of valve to control the

inventory in case of failure of pipeline or equipments.

2. Liaison with District Authority Services like Police, Medical, Fire Services etc. should be

further increase to respond in case of any emergency along with pipeline route.

3. Operation & maintenance procedures in accordance with ISO 9001 & other applicable

standards must be followed.




Reference: Risk Analysis Report of MECON INDIA

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