pipeline maintenance

7/30/2019 pipeline maintenance

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AS 2885.32001

Australian Standard

PipelinesGas and liquid petroleum

Part 3: Operation and maintenance

AS

2885.3


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This Australian Standard was prepared by Committee ME-038, Petroleum Pipelines.It was approved on behalf of the Council of Standards Australia on 27 July 2001and published on 6 August 2001.

The following interests are represented on Committee ME-038:

Australian Corrosion Association

Australian Gas Association

Australian Institute of Petroleum

Australian Petroleum Production and Exploration Association

Australian Pipeline Industry Association

Bureau of Steel Manufacturers of Australia

Cooperative Research Centre for Materials, Welding and Joining

Department of Labour New Zealand

Department of Minerals and Energy WA

Department of Mines and Energy (NT)

Department of Natural Resources and Environment (Victoria)

Department of Natural Resources and Mines (Qld)

Gas Association of New Zealand

Ministry of Energy and Utilities NSW

Primary Industries and Resources SA

Welding Technology Institute of Australia

Keeping Standards up-to-date

Standards are living documents which reflect progress in science, technology andsystems. To maintain their currency, all Standards are periodically reviewed, andnew editions are published. Between editions, amendments may be issued.Standards may also be withdrawn. It is important that readers assure themselvesthey are using a current Standard, which should include any amendments whichmay have been published since the Standard was purchased.

Detailed information about Standards can be found by visiting the StandardsAustralia web site at www.standards.com.au and looking up the relevant Standardin the on-line catalogue.

Alternatively, the printed Catalogue provides information current at 1 January eachyear, and the monthly magazine, The Australian Standard, has a full listing ofrevisions and amendments published each month.

We also welcome suggestions for improvement in our Standards, and especiallyencourage readers to notify us immediately of any apparent inaccuracies orambiguities. Contact us via email at [email protected], or write to the ChiefExecutive, Standards Australia International Ltd, GPO Box 5420, Sydney,NSW 2001.

This Standard was issued in draft form for comment as DR 00338.

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AS 2885.32001

Australian Standard



Originated in part as AS CB281972.Previous edition AS 2885.31997.

Second edition 2001.

COPYRIGHT

Standards Australia In ternational

All rights are reserved. No part of this work may be reproduced or copied in any form or by anymeans, electronic or mechanical, including photocopying, without the written permission of thepublisher.

Published by Standards Australia International LtdGPO Box 5420, Sydney, NSW 2001, Australia

ISBN 0 7337 4084 7


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PREFACE

This Standard was prepared by the joint Standards Australia/Standards New Zealand

Committee ME-038, Petroleum Pipelines, to supersede AS 2885.3

1997.This Standard is the result of a consensus among Australian and New Zealand

representatives on the Joint Committee to produce it as an Australian Standard.

This Standard has been reviewed and revised to correlate with the requirements of Safety

Case.

Due to significant changes in the industry and the regulatory environment, the Standard has

been restructured, and is based on Pipeline Integrity Management philosophy.

Changes have been made to the Standard to enable it to be viewed as a stand-alone

document whilst retaining and strengthening the references to AS 2885.1 and AS 2885.2.

The readability of the document has been improved by drawing together like requirements

into common sections, by improving the cross-references and by applying a consistent style

to the structure and wording.

The most important changes include the following:

(a) The addition of Pipeline Integrity Management principles.

(b) A major review of the Operating Condition Changes section.

(c) The inclusion of a records management process.

(d) Responsibilities of the operating authority have been clarified.

(e) Risk Assessment process has been further integrated.

(f) Contents of Safety and Operating Plan have been clarified.

(g) Approval requirements have been identified and listed in Appendix C.

(h) The development of a threat mitigation section.

(i) A revision of the Cathodic Protection section.

(j) The introduction of a Safety and Environment section.

(k) The inclusion of signage maintenance

(l) Coverage of SCADA maintenance.

The terms normative and informative have been used in this Standard to define the

application of the appendix to which they apply. A normative appendix is an integral partof a Standard, whereas an informative appendix is only for information and guidance.



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CONTENTS

Page

SECTION 1 SCOPE AND GENERAL

1.1 SCOPE.........................................................................................................................5

1.2 BASIS OF STANDARD ..............................................................................................5

1.3 APPLICATION............................................................................................................5

1.4 RISK MANAGEMENT ...............................................................................................6

1.5 REFERENCED DOCUMENTS...................................................................................6

1.6 DEFINITIONS ............................................................................................................6

SECTION 2 PREPARATION FOR OPERATION

2.1 GENERAL...................................................................................................................9

2.2 PLANS AND PROCEDURES ....................................................................................92.3 RESPONSIBILITIES FOR PERSONNEL ...................................................................9

2.4 READINESS FOR OPERATION ................................................................................9

2.5 DELAYED COMMENCEMENT OF OPERATION..................................................10

2.6 PURGING AND FILLING A PIPELINEPROCEDURES......................................10

SECTION 3 PIPELINE INTEGRITY MANAGEMENT

3.1 BASIS OF SECTION.................................................................................................13

3.2 GENERAL ................................................................................................................ 13

3.3 PIPELINE STRUCTURAL INTEGRITY .................................................................13

3.4 THREAT MITIGATION............................................................................................14

3.5 SAFETY AND ENVIRONMENT..............................................................................15

SECTION 4 PLANS AND PROCEDURES

4.1 GENERAL.................................................................................................................16

4.2 SAFETY AND OPERATING PLAN.........................................................................16

4.3 EMERGENCY PLANS..............................................................................................17

4.4 PROCEDURES..........................................................................................................19

SECTION 5 PIPELINE STRUCTURAL INTEGRITY

5.1 GENERAL.................................................................................................................20

5.2 OPERATING AND DESIGN CONDITIONS............................................................20

5.3 PIPELINE INSPECTION AND ASSESSMENT .......................................................20

5.4 PIPE WALL DEFECT ASSESSMENT .....................................................................215.5 COATINGS ............................................................................................................... 24

5.6 CATHODIC PROTECTION .....................................................................................25

5.7 INTERNAL SURFACES...........................................................................................26

5.8 STATIONS ................................................................................................................ 26

5.9 ANCILLIARY EQUIPMENT ....................................................................................27

SECTION 6 THREAT MITIGATION

6.1 GENERAL ................................................................................................................ 29

6.2 PIPELINE SURVEILLANCE....................................................................................29

6.3 PIPELINE MARKING...............................................................................................30

6.4 EXTERNAL INTERFERENCE PREVENTION .......................................................31

6.5 CONTROLLING ACTIVITIES NEAR PIPELINES.................................................. 32


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Page

SECTION 7 SAFETY AND ENVIROMENT

7.1 GENERAL................................................................................................................. 35

7.2 EMERGENCY RESPONSE.......................................................................................35

7.3 VENTING PROCEDURES........................................................................................35

7.4 PROCEDURES TO FREE PIPELINES OF HYDROCARBONS ..............................36

7.5 COMMUNICATIONS SYSTEMS.............................................................................37

7.6 SCADA......................................................................................................................37

7.7 PIPELINE FACILITY CONTROL ............................................................................38

7.8 NOISE ABATEMENT............................................................................................... 38

7.9 ENVIRONMENT.......................................................................................................38

7.10 ELECTRICAL SAFETY ON METALLIC PIPELINES.............................................38

SECTION 8 OPERATING CONDITION CHANGES

8.1 DESIGN CONDITION CHANGES...........................................................................398.2 PRESSURE TESTING OF DESIGN CONDITION CHANGES................................40

8.3 PIPELINE MODIFICATIONS...................................................................................40

8.4 REVIEW OF PRESSURE-CONTROL AND OVER-PRESSURE PROTECTION

SYSTEMS..................................................................................................................40

8.5 REVIEW OF DESIGN LIFE......................................................................................40

8.6 REVIEW OF MAXIMUM ALLOWABLE OPERATING PRESSURE (MAOP) ......41

8.7 REVIEW OF LOCATION CLASSES........................................................................41

8.8 REVIEW OF RISK ASSESSMENT ..........................................................................41

8.9 OPERATION OF A SUSPENDED PIPELINE ..........................................................41

8.10 ABANDONING A PIPELINE ...................................................................................42

8.11 ABANDONMENT OF ABOVE-GROUND PIPELINES...........................................42

8.12 ADDITIONAL REQUIREMENTS FOR ABANDONMENT .................................... 42

8.13 ABANDONMENT RECORDS..................................................................................43

SECTION 9 PIPELINE REPAIRS

9.1 GENERAL.................................................................................................................45

9.2 SUPERVISION..........................................................................................................45

9.3 COMMUNICATION AND CONTROL.....................................................................45

9.4 WORKING ON PIPELINES......................................................................................45

9.5 REPAIR STRATEGY................................................................................................48

9.6 WELDING ONTO AN IN-SERVICE PIPELINE ......................................................49

9.7 HOT-TAPPING OPERATIONS ................................................................................51

SECTION 10 RECORDS

10.1 GENERAL.................................................................................................................52

10.2 DESIGN, CONSTRUCTION AND COMMISSIONING RECORDS ........................52

10.3 OPERATION AND MAINTENANCE RECORDS ...................................................53

10.4 ABANDOMENT RECORDS.....................................................................................53

APPENDICES

A LIST OF REFERENCED DOCUMENTS..................................................................54

B DOCUMENT HIERARCHY......................................................................................56

C LIST OF APPROVAL REQUIREMENTS.................................................................57

D ASSESSMENT OF A CORRODED PIPELINE ........................................................59

E TYPICAL PIPELINE MARKERS .............................................................................70



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STANDARDS AUSTRALIA

Australian Standard



S E C T I O N 1 S C O P E A N D G E N E R A L

1.1 SCOPE

This Standard specifies the minimum requirements for the operation and maintenance of

pipelines complying with AS 2885.1 and AS 2885.2.

1.2 BASIS OF STANDARD

The purpose of the AS 2885 series of Standards is detailed in Part 1.

The basis of this part of the AS 2885 series of Standards is to provide important principles,

practices and practical guidelines for use by competent persons and organizations involved

in the operation and maintenance of high-pressure petroleum pipelines.

The fundamental principles on which this Part is based are the following:

(a) Important matters relating to safety, engineering design, materials, testing andinspection to be reviewed and approved by a responsible entity, referred to as the

operating authority. The responsible entity to be defined in each case.

(b) Operation and maintenance practices to be implemented to provide for continuedmonitoring and safe operation of the pipeline.

(c) Where the Standard does not provide detailed requirements appropriate to a specificitem, the principles and guidelines set out in the Standard to be the basis on which an

engineering assessment is made. Specific requirements of the Standard do not replace

the need for appropriate experience and engineering judgement.

1.3 APPLICATION

The requirements of this Standard apply to the operation and maintenance of pipelines

designed in accordance with AS 2885.1.

This Standard is not intended to be applied retrospectively to existing pipelines that have

not been modified unless the following requirements are met:

(a) The requirements of this Standard shall apply to the operation and maintenance ofexisting pipelines designed and built under those Standards superseded by this

Standard, where such pipelines are modified to operate under the conditions within

the scope of this Standard.

(b) Operating authorities, which operate and maintain pipelines that are not designed andconstructed in accordance with AS 2885.1, and where it is not feasible to physically

modify the pipeline, may apply this Standard provided the areas of non-compliance

with AS 2885.1 are documented and are subject to r isk assessment. Any actions

required to mitigate risk shall be approved in the safety and operating plan.
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1.4 RISK MANAGEMENT

Risk management during operation and maintenance shall be addressed in accordance with

the requirements of AS 2885.1.

1.5 REFERENCED DOCUMENTS

The documents referred to in this Standard are listed in Appendix A.

1.6 DEFINITIONS

For the purpose of this Standard, the definitions given in AS 1929, AS 2812,

AS/NZS 2832.1 and those below apply.

1.6.1 Approved and approval

Approved by the operating authority, and includes obtaining the approval of the relevant

regulatory authority where this is legally required.

NOTE: Approval requires a conscious act and is given in writing.

1.6.2 Casing

A conduit through which a pipeline passes, to protect the pipeline from excessive external

loads or to facilitate the installation or removal of that section of the pipeline.

1.6.3 Collapse

A permanent cross-sectional change to the shape of a pipe (normally caused by instability,

resulting from combinations of bending, axial loads and external pressure).

1.6.4 Component

Any part of a pipeline other than the pipe.

1.6.5 Construction

Activities required to fabricate, construct and test a pipeline and associated infrastructure,

and to restore the route of a pipeline.

1.6.6 Defect

A discontinuity or imperfection of sufficient magnitude to warrant rejection on the basis of

the requirements of this Standard.

1.6.7 Dent

A depression in the external surface of the pipe caused by mechanical damage, which

produces a visible irregularity in the curvature of the pipe wall without reducing the wall

thickness (as opposed to a scratch or gouge, which reduces the pipe wall thickness)

1.6.8 Diameter

The outside diameter nominated in the material order.

1.6.9 Fitting

A component, including the associated flanges, bolts and gaskets used to join pipes, to

change the direction or diameter of a pipeline, to provide a branch, or to terminate a

pipeline.

1.6.10 Fluid

Any liquid, vapour, gas or mixture of any of these.

1.6.11 Gas

Any hydrocarbon gas or mixture of gases, possibly in combination with liquid petroleum

condensates or water.



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1.6.12 High vapour pressure liquid (HVPL)

A liquid or dense phase fluid which releases significant quantities of vapour when its

pressure is reduced from pipeline pressure to atmospheric, e.g., LP gas.

1.6.13 Hoop stress

Circumferential stress in a cylindrical pressure-containing component, arising from internal

pressure.

1.6.14 Hot tap

A connection made to an operating pipeline containing hydrocarbon fluid.

1.6.15 Inert gas

A non-reactive and non-toxic gas such as argon, helium or nitrogen.

1.6.16 Inspector

A person appointed by the operating authority to carry out inspections required by this

Standard.

1.6.17 Leak test

A pressure test that determines whether a pipeline is free from leaks, which is performed in

accordance with AS 1978

1.6.18 Location class

An area classified according to its general geographical and demographical characteristics,

as defined in AS 2885.1.

1.6.19 Maximum allowable operating pressure (MAOP)

The maximum pressure at which a pipeline may be operated (see Clause 5.2 (b)).

1.6.20 May

Indicates the existence of an option.

1.6.21 Operating authority

The organization responsible for the design, construction, testing, inspection, operation and

maintenance of pipelines and facilities within the scope of this Standard.

1.6.22 Petroleum

Any naturally occurring hydrocarbon or mixture of hydrocarbons in a gaseous or liquid

state, which may contain hydrogen sulfide, nitrogen, helium, carbon dioxide and trace

quantities of other materials.1.6.23 Pig

A device that is propelled inside a pipeline by applied pressure.

1.6.24 Pig trap (scraper trap)

A fabricated component to enable a pig to be inserted into or removed from an operating

pipeline.

1.6.25 Piping

An assembly of pipes, valves and fittings connecting auxiliary and ancillary components

associated with a pipeline.

1.6.26 Pre-tested

The condition of a pipe or a pressure-containing component that has been subjected to a

pressure test in accordance with this Standard before being installed in a pipeline.


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1.6.27 Protection measures

(a) Proceduralmeasures for protection of a pipeline, to minimize the occurrence ofactivities by third parties, which could damage a pipeline.

(b) Physicalmeasures for protection of a pipeline that prevent external interference

from causing sufficient damage to a pipeline to cause penetration of the pipe wall,rupture the pipeline or reduce the pressure strength of the pipeline below the

maximum allowable operating pressure.

1.6.28 Regulatory authority

An authority with legislative powers relating to petroleum pipelines.

1.6.29 Risk assessment

A systematic identification and evaluation of threats to personnel and pipelines to facilitate

appropriate management of these threats in accordance with the methodology prescribed in

AS 2885.1.

1.6.30 Shall

Indicates that a statement is mandatory.

1.6.31 Should

Indicates a recommendation.

1.6.32 Specified minimum yield stress (SMYS)

The minimum yield stress for a pipe material that is specified in the manufacturing standard

with which the pipe or fittings used in the pipeline complies.

1.6.33 Station pipe work

Those parts of a pipeline within a station (e.g., pump station, compressor station, meteringstation) which begin and end where the pipe material specification changes to that for the

mainline pipe work.

1.6.34 Strength test

A pressure test that confirms that the pipeline has sufficient strength to allow it to be

operated at MAOP.

1.6.35 Telescoped pipeline

A pipeline that is made up of more than one diameter or MAOP, tested as a single unit.

1.6.36 Wall thickness, nominal

The thickness of the wall of a pipe that is nominated for its manufacture, ignoring themanufacturing tolerance provided in the nominated Standard to which the pipe is

manufactured. (Quantity symbol N.)



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S E C T I O N 2 P R E P A R A T I O N F O R O P E R A T I O N

2.1 GENERAL

Preparations for operation shall be deemed complete when the plans and procedures set out

in this Section have been implemented. With the preparation completed and with approval

given to start operation, the filling of the pipeline can occur and the pipeline can then be put

into operation.

2.2 PLANS AND PROCEDURES

The operating authority shall ensure that the following plans and procedures have been

prepared and approved as appropriate, and that personnel have been properly trained in

their application:

(a) A safety and operating plan including an emergency plan (see Sections 4 and 7).

(b) Operating, maintenance and repair procedures.

(c) An environmental code of practice to deal with possible pipeline leaks and ruptures.

2.3 RESPONSIBILITIES FOR PERSONNEL

Personnel responsible for the operation and maintenance of the pipeline shall, as applicable

to their position, be

(a) adequately trained and experienced in all aspects of the equipment in their control;

(b) adequately briefed in the requirements of the actions defined in the risk assessment;

(c) aware of properties of the fluid, including its hazard level in accordance withAS 4343;

(d) capable of ensuring the safe disposal of any accidentally discharged fluid; and

(e) capable of arranging for damaged pipelines to be repaired.

2.4 READINESS FOR OPERATION

Pipelines shall not be considered ready to commence or recommence operation unless, as a

minimum, the following check list has been completed:

(a) The pipeline complies with the requirements of all relevant parts of AS 2885.1.

(b) The hydrostatic strength and leak test requirements have been achieved anddocumented.

(c) The MAOP has been established.

(d) The welds of tie-ins to existing facilities, which have not been subjected to testing inaccordance with Item (b), have been inspected by an approved non-destructive

examination method, and comply with AS 2885.2.

(e) Components have been tested for satisfactory operation. Where impractical, otherappropriate inspection shall be carried out.

(f) Operating, maintenance and emergency personnel have been trained.

(g) The pipeline is cathodically protected as required by AS 2885.1.(h) Threat mitigation measures have been implemented in accordance with Section 3.4.


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NOTES:

1 Additional site-specific aspects may need to be evaluated prior to commencement of

operation.

2 Initial operation may be approved before completion of the field work, provided that the

incomplete work does not directly affect the safety of the pipeline, the public, or the operating

personnel.

3 For a list of plans and procedures that this Standard requires to be approved, see Appendix C.

2.5 DELAYED COMMENCEMENT OF OPERATION

Where a pipeline is to be placed in operation with a time delay, it shall meet the

requirements of Clause 2.4. If the hydrostatic test fluid is allowed to remain in the pipeline,

the test fluid shall either be dosed with a corrosion inhibitor or the pipeline filled with a

fluid that inhibits corrosion, unless it can be demonstrated that such measures are not

warranted.

Where the test fluid is removed, the pipeline shall be dried or purged, or both, with inert gas

to produce a moisture level that will not promote corrosion during the delay period.

Where the pipeline is left filled with a fluid, precautions shall be taken to ensure that no

damage is caused by overpressure due, for example, to thermal expansion effects.

During the period between the hydrostatic test and the initial operation, the pipeline

integrity shall be maintained in accordance with this Standard.

Corrective action shall be taken when an inspection reveals that unacceptable corrosion is

occurring.

2.6 PURGING AND FILLING A PIPELINE PROCEDURES

2.6.1 General

To bring a pipeline into service, the operating authority shall ensure that

(a) a pipeline is purged and filled in a safe manner;

(b) work is undertaken on a pipeline only when all relevant aspects of this Standard havebeen complied with;

(c) an approved procedure is developed specific to the pipeline and the nature of the fluidbeing purged, filled or commissioned; and;

(d) the approved procedure is implemented during purging and filling or commissioning.

The procedure shall address the following requirements:

(i) The appropriate number, experience, training and induction of personnel involved in

the procedure.

(ii) The level and control of the filling rate.

(iii) Controlling and monitoring the discharge of displaced fluids and venting of gases.

(iv) Limiting the mixing of fluids at their interface.

(v) Controlling and minimizing the formation of explosive gaseous mixtures at the gas/air

interface.

(vi) Removing unacceptable residues from the pipeline.

(vii) Continually discharging any static electricity generated to an effective earth (seeAS/NZS 1020)

(viii) A job hazard analysis.



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(ix) Appropriate signage.

(x) Minimization of hydrocarbon discharge.

(xi) Preventing the discharged fluid from causing unacceptable environmental effects such

as damage to crops, excessive erosion, soil contamination or contamination of

watercourses or bodies of water.

NOTE: See AGA Operating Section Report Purging Principles and Practice, Catalogue No.

XK0775 as amended.

2.6.2 Filling a gas pipeline

Prior to filling a gas pipeline, a plan shall be prepared, which shall contain all relevant

supporting calculations.

When a pipeline is being purged of air by the use of gas, prior to filling, consideration shall

be given to the safety and operational consequences of the formation of an explosive

mixture at the gas/air interface.

A direct purge with gas may be used provided the approved procedures meet the conditionsand requirements of AGA Operating Section Report Purging Principles and Practice,

Catalogue No. XK0775 as amended.

During purging gas should be released into one end of the pipeline in a controlled and

continuous flow at an appropriate rate for the pipeline being purged. A slug of inert gas of

sufficient length to separate the air from the gas to control the formation of an explosive

mixture, may be released into the pipeline before the gas.

Pigs or spheres may be used in some cases to reduce mixing at the interface and, therefore,

reduce the volume of explosive mixture or reduce the volume of inert gas required.

Where the above conditions cannot be met or controlled for the duration of the purge, then

the operating authority shall ensure that the approved procedure, using an alternativetechnique, purges the pipeline in a safe manner.

2.6.3 Filling a liquid petroleum pipeline

Prior to filling a liquid pipeline, a plan shall be prepared, which shall contain all relevant

supporting calculations.

The plan shall control the speed of the interface by applying appropriate back pressure at

the gas release point.

Where air in a pipeline is to be displaced by a hydrocarbon liquid, a slug of appropriate

liquid between spheres or batching pigs should separate the air and hydrocarbon liquid.

Where the slug in a pipeline is to be displaced by a hydrocarbon liquid, it shall bephysically separated from the hydrocarbon liquid.

The flashpoint of the initial hydrocarbon liquid introduced into a pipeline shall, where

possible, be not less than 61C, to prevent the formation of explosive gas/air mixtures.NOTES:

1 The operating authority should consider the risks of introducing lower flashpoint hydrocarbon

liquid and take appropriate measures.

2 Physical separation using a batching pig is recommended. This can be improved using a slugof inert liquid or high flashpoint hydrocarbon in front of the pig to improve separation.

3 The use of an immiscible fluid like water may introduce contamination risks, and the risk of

corrosion to the pipe invert where trace quantities may exist for long periods after the initial

filling.

When the pipeline has not been designed to allow pigging, alternative procedures shall be

developed and approved.


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2.6.4 Filling a high vapour pressure liquid (HVPL) pipeline

Where the HVPL consists of a single component hydrocarbon, the pipeline may be filled in

the gas phase in accordance with Clause 2.6.2, upon which the pipeline shall be pressurized

to above the dewpoint of the HVPL and the pipeline confirmed as fully liquid. Procedures

for the pressurization and recondensing of the gas phase HVPL shall be approved.Where the HVPL is a mixture of hydrocarbon components, the pipeline should be filled first

with water or a suitable low vapour pressure hydrocarbon liquid, and then that liquid

displaced by the liquid phase HVPL. Suitable spheres or pigs should separate the two

liquids. The pressure shall be maintained at, or above, the bubble point of the HVPL, to

maintain it in its liquid phase.

NOTE: Where the HVPL consists of a mixture of hydrocarbon components other than ethane and

the risk of contamination with inerts is considered low, the operating authority should complete a

process simulation and prepare specific procedures to fill the pipeline in the gas phase.

The operating authority needs to be aware of the effects of the variation of the composition of the

recondensed HVPL along the pipeline, the potential low temperature effects and of the difficulty

in determining when the pipeline is in a total liquid state.



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S E C T I O N 3 P I P E L I N E I N T E G R I T Y

M A N A G E M E N T

3.1 BASIS OF SECTION

For the purpose of this Standard, pipeline integrity management ensures that the high

pressure pipeline infrastructure remains fit for purpose by implementing a systematic

approach to the utilization of resources on high pressure pipeline system design,

construction, operation and maintenance activities and the application of sound engineering

principles with due regard to safety and the environment.

The operating authority is responsible for ensuring continued Pipeline Integrity during the

life of the pipeline.

3.2 GENERAL

This Section details the key aspects of pipeline integrity management, which ensures the

risks management strategies defined in the risk assessment carried out in accordance with

the requirements of AS 2885.1, are implemented and managed effectively. Ongoing

management of risks is required as part of a total pipeline risk management strategy. The

operating authority shall ensure that approved actions, as a result of the risk assessment,

and any other risk management assessments associated with operation and maintenance

activities are documented and implemented.

This Standard is based on pipeline integrity management principles. Pipeline integrity

management as it relates to the operation and maintenance of pipelines covers the

following:

(a) Pipeline structural integrity including the technical aspects of maintaining pipelinesand facilities.

(b) Threats to pipeline infrastructure.

(c) Safety and the environment.

3.3 PIPELINE STRUCTURAL INTEGRITY

Structural pipeline integrity is achieved when the pipeline is leak tight, operating within the

design parameters and able to safely withstand all identifiable forces to which it may be

subjected during operation, including the MAOP (see Section 5).

In order to maintain structural integrity, the operating authority shall ensure that a pipeline

has the following:

(a) Sufficient wall thickness at all locations to contain hydrocarbons at the systemMAOP. The minimum allowable wall thickness shall be assessed as follows:

(i) For a new pipeline, and for an in-service pipeline containing no corrosionanomalies or uniform general wall thickness loss, the minimum wall thickness shall

be calculated in accordance with AS 2885.1.

(ii) For a pipeline with physical damage, the minimum wall thickness shall beassessed in accordance with Clause 5.4.1 or other approved method.

(iii) For a pipeline with corrosion anomalies, the minimum wall thickness shall beassessed in accordance with Clause 5.4.2.

(b) Sufficient structural integrity at joints to prevent leakage at the MAOP.

(c) An appropriate overpressure control system to ensure that the pipeline pressure doesnot exceed the MAOP during normal operation.


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The continued structural integrity of pipelines relies on elements of pipeline design,

construction and operation and maintenance. Procedures shall be developed to ensure

structural integrity of the pipeline infrastructure including compressor and pump stations,

regulator stations, and metering facilities are retained during operation and maintenance

activities. The procedures shall be approved.

The operating authority shall address structural integrity issues of at least the following:

(i) Protective coatings.

(ii) Pipeline wall thickness.

(iii) Valves, pig traps, launcher enclosures.

(iv) Pipe supports.

(v) Cathodic protection systems/inhibition/corrosion control systems.

(vi) Pressure control and protective equipment.

(vii) Stations.(viii) Casings.

(ix) Structures.

(x) Joints.

3.4 THREAT MITIGATION

3.4.1 General

The risk assessment, carried out in accordance with the requirements of AS 2885.1, requires

that the operating authority identifies and assesses the risks associated with threats to the

pipeline and instigates appropriate measures to mitigate these threats (see Section 6).

To adequately manage risk, the operating authority shall develop, implement and monitor

the threat mitigation measures and risk management procedures that have been identified in

risk assessment, and documented and approved in the safety and operating plan.

The minimum areas, identified in the risk assessment to be included in the safety and

operating plan shall be the following:

(a) Physical measures:

(i) Separation by burial.

(ii) Separation by barriers (e.g., crash barriers).

(iii) Separation by exclusion (e.g., fencing).(iv) Resistance to penetration due to wall thickness.

(v) Resistance to penetration by barriers (e.g., concrete slabs).

(b) Procedural protection measures:

(i) One-call systems.

(ii) Third party awareness programs.

(iii) Landowner and emergency service liaison.

(iv) Pipeline marking.

(v) Marker tape.

(vi) Patrolling.

(vii) Permit to work



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(viii) Approved procedures

(ix) Inspection or supervision of third party activities or proposed activities near thepipeline.

(c) Operating authority review measures:

(i) Regular review of MAOP in accordance with Clause 8.6.

(ii) Review of class location in accordance with Clause 8.7.

(d) Operating authority activities:

(i) Coating assessment and repairs.

(ii) Pipe wall assessment and repairs.

(iii) Joint assessment and repair.

(iv) Loss of cover repair.

(v) Pigging.

(vi) Venting.

(vii) Purging.

(viii) High capacity utilization.

(ix) Incident response, review and prevention.

(x) In-service modifications.

3.5 SAFETY AND ENVIRONMENT

3.5.1 General

The operating authority shall ensure that all its actions and activities do not unduly expose

its personnel, the public or the environment to unacceptable risks (see Section 7). Measures

to mitigate these risks shall be documented in the operating and maintenance procedures

and referenced in the safety and operating plan.

Areas to be considered for inclusion in the safety and operating plan include the following:

(a) Safety of the public.

(b) Safety of personnel working on the p ipeline.

(c) Safety of contractors.

(d) Minimization of environmental impacts.

(e) Incident management.


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S E C T I O N 4 P L A N S A N D P R O C E D U R E S

4.1 GENERAL

The operating authority, using the results of the risk assessment carried out in accordance

with the requirements of AS 2885.1 and its experience and knowledge of the facilities and

conditions under which they are operated and maintained, shall develop a safety and

operating plan and procedures and emergency plan based on the relevant requirements of

this Standard.

Operating and maintenance personnel that are required to carry out these procedures shall

be suitably qualified, trained and experienced to accepted industry standards.

NOTE: These plans should be implemented prior to the pipeline bring placed into operation.

4.2 SAFETY AND OPERATING PLAN

4.2.1 General

A safety and operating plan shall be written and it shall be approved. The plan shall be

monitored reviewed and updated every two years if significant incremental change has

occurred and, in any event, when the scope of any single change is significant. Significant

change shall be considered to have taken place if any event initiates an operational,

technical or procedural change in the elements covered by Items (a) to (g) listed below, or if

the engineering design has been upgraded or modified.

As a minimum, risk assessments shall be reviewed and updated to coincide with any update

of the safety and operating plan.

The safety and operating plan shall detail the policy of personnel, public and environment

protection, as identified in the risk assessment, including measures to

(a) protect the pipeline and associated installations;

(b) promote public awareness of the pipeline;

(c) operate and maintain the pipeline safely;

(d) respond to emergencies;

(e) prevent and minimize product leakage;

(f) carry out inspections in accordance with Clause 5.3; and

(g) ensure that the plans and procedures continue to comply with the engineering design.

4.2.2 Safety and operating plan requirements

The safety and operating plan shall include, but not be limited to, the following:

(a) A description of the organization structure and responsibilities of key positionsincluding the positions with approval authority for the procedures and plans.

(b) A description of the pipeline system operation including suitable maps (alignmentsheets) showing the route of the pipeline, the location of associated facilities such as

compressor and pump stations, SCADA control centres, transmission towers, cathodic

protection points, valve stations, metering points, and launching and receiving

stations.

(c) Risk assessment in accordance with the requirements of AS 2885.1 that includes(i) a systematic review of threats identified in the risk assessment together with

identification of any further operational threats, their potential causes, and the

consequences (in qualitative terms) of such events;



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(ii) the operational, maintenance and organization measures to eliminate thosethreats or reduce them to an acceptable level under AS 2885.1 (see Section 6);

and

(iii) the consequence analysis of any hazardous events and the design, operational,

maintenance and organizational measures required to reduce the level of risk toas low as reasonably practicable (ALARP).

(d) A summary of operational and maintenance processes and procedures forimplementation of the required measures identified in Clause 4.2.2(c) including

(i) maintenance schedule;

(ii) operating procedures;

(iii) a maintenance plan;

(iv) pipeline inspections as detailed in Clause 5.3; and

(v) cathodic protection surveys.

(e) A summary of the contents of emergency response plans covering as a minimum(i) impact events;

(ii) fire;

(iii) rupture;

(iv) leak/spill; and

(v) natural events.

(f) A summary of the records management plan addressing as a minimum

(i) the records to be maintained;

(ii) retention;

(iii) storage methods; and

(iv) record maintenance procedures.

(g) Audit schedule.

4.2.3 Audit of compliance to safety and operating plan

The operating authority shall, at periods defined in the safety and operating plan, conduct a

full audit of each of the items listed in the safety and operating plan to determine that work

is being carried out according to the plan and the written procedures. The audit shall

identify any non-compliance with the plan or procedures. The operator shall then implement

appropriate measures to rectify any non-compliance and ensure continuing pipeline

integrity.Audits shall be carried out by appropriately qualified and experienced personnel.

NOTES:

1 See Appendix B for a description of the document hierarchy.

2 See Appendix C for list of documents requiring approval.

4.3 EMERGENCY PLANS

The following recommendations are given as a general guide with respect to preparing

emergency plans:

(a) The number of experienced operative and supervisory staff should be adequate at all

times to respond to any reported emergency event. Procedures should be establishedin order to ensure that personnel attend the site of the emergency as soon as possible

in the circumstances. An emergency staffing structure and an up-to-date contact list

of such personnel should be documented and maintained.


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(b) Emergency procedures should be documented. All operational personnel should bemade aware of emergency procedures and be fully trained in their application

including any action required under such procedures.

(c) Sound incident management procedures, covering the necessary planning and

preparation to implement emergency actions in the event of an accident, a failure orother emergency may include the following:

(i) Promptly and expediently providing remedial action for the safety of the publicand operating personnel, minimizing damage to property and protecting the

environment.

(ii) Liaising with the appropriate authorities, including the regulatory authority, andother relevant bodies.

(iii) Limiting the quantity of and controlling any accidentally discharged fluid.

(iv) Preventing or controlling the spread of vapour by the use of temporary flares,blow-downs, or other means.

(v) Giving particular attention to those sections of the pipeline that present thegreatest risk to the public or the environment or, because of construction

features, have special requirements or extraordinary maintenance requirements.

(vi) Critically reviewing and revising the plans and procedures at approvedintervals.

(vii) Revising the plans and procedures whenever there is a change in the fluid or theoperating conditions along the route or the equipment.

(viii) Carrying out periodic simulated exercises at approved intervals, to determinethe procedural correctness and the understanding by personnel of the

emergency procedures.(ix) Having adequate emergency equipment, pipe and fittings fit for the intended

purpose readily available at all times, complete with traceable material test

certificates.

(d) Emergency plans should address the following:

(i) Attendance at the emergency site to analyse and develop a response plan.

(ii) Precautions to take in the event of either HVPL or a gas cloud.

(iii) Reduction of the pressure in the pipeline.

(iv) Closure of any valves on each side of any dangerous or potentially dangerous

situation.

(v) Maintenance or curtailment of supply.

(vi) Spill control.

(vii) Establishment of a control centre from which emergency activities may becoordinated.

(viii) Instruction to the appropriate authorities and other relevant bodies of the actionto be taken.

(ix) Evacuation of any endangered members of the public and unauthorizedpersonnel.

(x) Prohibition of road and rail traffic, low-flying aircraft and isolation of electricalpower in any areas that may be hazardous to safety, to reduce any risk of

ignition and resultant dangers.



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(xi) Expeditious transport of repair equipment, materials and personnel to the site.

(xii) Additional prudent action that any particular circumstances may require.

(xiii) Distribution and control of plans.

Emergency plans shall be reviewed periodically at periods not in excess of 2 years and, ifnecessary, shall be revised and approved.

4.4 PROCEDURES

The operating authority shall

(a) have written procedures (controlled document), which shall be approved andreviewed at nominated intervals, for the operation and maintenance of the pipeline

and any associated systems, including those necessary for maintaining structural

integrity in accordance with this Standard;

(b) maintain a list of positions responsible for approval of operation and maintenance

procedures and risk assessment as defined in the Standard;(c) document and record the interval between reviews of the safety and operating plan,

emergency plan, and operation and maintenance procedures; and

(d) operate and maintain the pipeline in compliance with these procedures.

The procedure specified in Clause 4.4(a) shall include detailed plans and instructions for

persons responsible for the operation and maintenance of the pipeline during normal

operation and maintenance.

The operating authority shall maintain a record of training and competency of operation and

maintenance personnel carrying out the operation and maintenance procedures.


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S E C T I O N 5 P I P E L I N E S T R U C T U R A L

I N T E G R I T Y

5.1 GENERAL

The operating authority shall ensure that appropriate systems are identified, implemented

and maintained to ensure pipeline structural integrity for the design life of the pipeline.

5.2 OPERATING AND DESIGN CONDITIONS

The operating authority shall

(a) operate a pipeline only when it conveys the fluid or fluids under the conditions(including subsequent changes) for which it was designed, constructed, tested, and

approved;

(b) ensure that during normal operation, the operating pressure at any point in thepipeline does not exceed the MAOP, and that transient pressure does not exceed110% of the MAOP;

(c) ensure that the operating temperature is such that the coating temperature rating andthe thermal stress limits used in the pipeline design are not exceeded; and

(d) ensure that operating conditions are such that the likelihood of stress corrosioncracking initiation or growth is minimized.

5.3 PIPELINE INSPECTION AND ASSESSMENT

5.3.1 General

Periodic inspections shall be carried out to identify actual or potential problems that couldaffect the integrity of the pipeline. The operating authority shall plan and perform any

maintenance required to rectify and manage any such problems.

Inspections shall be carried out by approved and appropriately trained and experienced

personnel.

The inspection and assessment of a pipeline shall include the following:

(a) A full visual survey of all above-ground sections of the pipeline, including supportsand associated equipment, to locate and assess any defects.

(b) An audit of corrosion control facilities to assess their effectiveness in accordancewith the corrosion-monitoring program required by this Standard. This includes

cathodic protection systems, pipeline coatings, surge protection systems, static earthsystems, and inhibitor dosing facilities.

(c) Inspections of actual or potential problems identified in the ongoing risk assessmentsuch as river or creek crossings, areas prone to ground instability and pipe supports at

bridge crossings.

NOTE: Where available, intelligent pigging results should also be considered when assessing

pipeline integrity.

(d) Inspections of any sections on the pipeline identified in the ongoing risk assessmentas being of higher propensity for development of stress corrosion cracking.

5.3.2 Frequency of inspection assessment

The frequency of inspection and assessment should be documented and approved and basedon the past reliability of the pipeline, historical records, current knowledge of its condition,

the rate of deterioration (both internal and external corrosion, coating degradation and the

like), and statutory requirements.



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5.3.3 Leakage survey and detection

The operating authority shall provide for leakage detection systems or periodic leakage

surveys of the pipeline in its operating and maintenance plan. The types of surveys selected

shall be effective for determining whether a potentially hazardous leakage exists. The

extent and frequency of the leakage surveys shall be determined by the operating pressure,piping age, class location, whether the pipeline transports gas without an odorant and the

ability to detect or observe product leakage.

5.3.4 Assessment of results and appropriate action

Where the integrity of a pipeline, or a section of a pipeline, is assessed as being inadequate

or at immediate risk, the operator shall immediately take steps to prevent failure of the

pipeline until the integrity of the pipeline is restored.

Measures shall be taken to mitigate the risk of a leak or failure to the minimum. This may

be by a reduction in pressure, by passing, or by carrying out temporary repairs and

appropriately adjusted surveillance.

5.3.5 Internal surfaces

Notwithstanding the requirements of Clause 5.3.2 where a part of any pipeline is removed

for any reason, the internal surface shall be inspected to confirm the suitability of, or the

requirement for, an internal corrosion control program. Suitable measures shall be

implemented to address any observed problems.

5.3.6 External surfaces

5.3.6.1 Above-ground pipelines

Above-ground pipelines shall be inspected for evidence of corrosion or damage to or

deterioration of any anti-corrosion coatings at intervals defined in the safety and operating

plan, and the rate of corrosion shall be assessed. Where the rate of corrosion will reduce thedesign life, remedial action shall be taken.

NOTE: Suitable action may include a reduction of the design life.

5.3.6.2 Buried and submerged uncoated pipelines

Buried or submerged uncoated pipelines shall be surveyed using approved techniques at

intervals as specified in the safety and operating plan. Pipelines shall be inspected at

positions that are not more than 1 km apart and wherever the most corrosion is expected to

occur.

5.3.6.3 Buried and submerged anti-corrosion-coated pipelines

Whenever any part of a buried or submerged anti-corrosion coated pipeline is exposed, it

shall be inspected for corrosion and evidence of damage to, or deterioration of, any anti-corrosion coatings (see Clause 5.5.2).

5.4 PIPE WALL DEFECT ASSESSMENT

5.4.1 Damaged pipework

Gouges, grooves and notches less than 0.25 mm are considered harmless.

Gouges, grooves and notches above 0.25 mm and up to 10% of wall thickness may be

removed by grinding. The requirements for non-destructive testing (NDT) for micro-

cracking should be assessed.

Wall thickness loss due to grinding may be assessed in the same manner as corrodedpipework.


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Unless detailed analysis has been carried out to confirm the acceptability of an anomaly,

anomalies in excess of the following shall be removed, replaced or otherwise repaired:

(a) Dents, as described in AS 2885.1 except that the maximum depth specified may beincreased to 6% of the pipe diameter.

(b) Gouges grooves and notches that are outside the criteria set out in AS 2885.1.

Combined pipe wall anomalies shall be subjected to detailed assessment.

NOTE: Detailed analysis may be undertaken using CSAZ662 Oil and Gas Pipeline Systems.

This allows, subject to stated conditions, repair of dents containing stress concentrators by

grinding, by pipe replacement, by pressure containment sleeve, or by reinforcement sleeve.

5.4.2 Corroded pipework

5.4.2.1 General

Where corrosion is detected, it shall be investigated to determine its nature, extent, depth

and cause. The corrosion shall be evaluated and the current MAOP shall be confirmed. In

the event that the MAOP is determined to have been compromised, a safe operatingpressure shall be determined by assessment in accordance with Clause 5.4.3 and, if

necessary, either a new MAOP shall be established or the corroded portion of the pipeline

shall be repaired or replaced.

Corroded pipelines shall be protected against further corrosion in accordance with

AS 2885.1.

NOTE: Figure 5.1 provides a flow chart for assessing corrosion features.

5.4.2.2 Safety precautions

Great care shall be taken when work is carried out on a corroded portion of pipeline.

The operating pressure shall either not exceed the pressure at which the corroded portion

was subjected to at the time of identification, or it should be reduced to a safe level(initially 80% of normal operating pressure). This pressure should not be exceeded until

such time as the corroded area has been cleaned and inspected, the extent and depth of

corrosion has been determined and an assessment has been made of the corroded portion of

the pipeline. Prior to the commencement of any activity, an approved plan shall be

prepared. Where the contents of the pipeline are liquid and locked in between valves,

consideration shall be given to any increase in pressure that may be caused by changes in

temperature.

5.4.3 Assessment of corroded pipework

5.4.3.1 General

The assessment required by Clause 5.4.2.1 shall be made by any one of the followingmethods:

(a) Calculation, in accordance with Appendix D, Paragraph D3.

(b) AGA Project PR3-805.

NOTE: This program is based on the calculation method given in Appendix D, Paragraph D3

but is less conservative.

(c) Pressure testing, in accordance with Clause 5.4.3.2.

(d) Other approved method.



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NOTES:

1 The design pressure (Pd) shall be calculated as follows:

D

F

Pydpd

d

2

=

where

Pd = design pressure, in megapascals

Fd = design factor

dp = wall thickness for design internal pressure, in millimetres

y = yield stress, in megapascals

D = nominal outside diameter

2 Test pressure = 1.25 Pd

FIGURE 5.1 FLOW CHART FOR ASSESSING CORROSION DEFECTS


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5.4.3.2 Assessment by pressure testing

Where an assessment is to be made by pressure testing, the pipeline shall be tested in

accordance with AS 2885.1 and its MAOP determined in accordance with Appendix D,

Paragraph D2.

The normal maximum pressure, recorded or determined for the corroded section over thesix months prior to the discovery of the corrosion, may be deemed to be a test pressure for

the purposes of recalculating the MAOP in accordance with this Clause.

Where the original design included an allowance (G) (see AS 2885.1) and it can be shown

that the original allowance is not required for the corroded section of pipe, a revised value

for G may be used in the re calculation of MAOP. The revised value shall be approved.

5.5 COATINGS

5.5.1 Above-ground pipework

Where, after inspection (see Clause 5.3.6.1), external corrosion that will compromise the

integrity of the pipework before the next integrity assessment is identified, the operating

authority shall take appropriate remedial action. This could include repair or renewal of the

coating. Specific assessment of the coating should be made at crevice areas such as pipe

supports and on the underside of the pipework. The pipe wall should also be inspected for

corrosion at areas of blistered or disbonded coating.

Where installed insulation shall be maintained in a condition such that

(a) water cannot reach and collect next to the pipe surface; and

(b) the requisite thermal insulation performance is maintained.

NOTES:

1 Corrosion under thermal or acoustic insulation can be a severe problem, especially if the

pipeline is in intermittent service (i.e., subject to fluctuating temperatures encompassing the

water vapour dewpoint). Inspection for corrosion under the insulation should be a regular

feature of assessment surveys.

2 The coating system under insulation needs to be adequate to prevent corrosion under the

conditions it will be subjected to.

3 Corrosion within crevices between surfaces, such as at pipe support saddles, can be a severe

problem, which can be difficult to identify by simple visual inspection.

4 Coating inspection of ground entry locations should be in accordance with Clause 5.9.4.

Records of the coating condition shall be kept.

5.5.2 Below-ground pipework

Assessment of the coating condition on below-ground pipework shall be achieved by

evaluation of some or all of the following:

(a) Cathodic protection data.

(b) Special coating defect surveys (eg. Pearson or DC-pulsed method surveys).

(c) Visual inspection at selected locations in bellhole excavations and where the pipelineis exposed for other reasons.

The coating and/or the cathodic protection system shall be maintained to a standard such

that

(i) the cathodic protection system effectively maintains protection at all coating defects;

and

(ii) coating disbondment is minimized.

Records of the coating condition shall be kept.



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5.5.3 Coating repairs

Where a repair is made to a pipeline coating, the material used shall be compatible with the

original coating and shall have been demonstrated by test, investigation or experience to be

suitable for the method of installation, the service conditions and the environment.

Procedures for application of the repair shall be developed so that the desired physical andchemical qualities are obtained. The application thereafter shall be in strict accordance with

the procedures. Surface preparation, application and testing of the coating shall be subject

to an approved quality control program.

5.6 CATHODIC PROTECTION

5.6.1 Criteria

Criteria for pipeline cathodic protection shall be as specified in AS/NZS 2832.1

5.6.2 Personnel

The parties responsible for the monitoring, survey, inspection, testing and maintenance ofthe cathodic protection system shall have the requisite experience and qualifications in

cathodic protection as approved by the operating authority.

NOTE: The Australasian Corrosion Association provides training for personnel in the Corrosion

Prevention Industry.

5.6.3 Commissioning of cathodic protection systems

Commissioning of cathodic protection systems shall be carried out in accordance with the

requirements of AS/NZS 2832.1.

5.6.4 Operation, maintenance and monitoring of cathodic protection systems

Operation, maintenance and monitoring of cathodic protection systems shall be carried out

in accordance with the requirements of AS/NZS 2832.1

AS/NZS 2832.1 contains information in the following areas:

(a) Criteria for cathodic protection.

(b) Measuring techniques and equipment.

(c) Operation of cathodic protection systems.

Where any inspection indicates that satisfactory protection is not fully achieved on the

pipeline, timely and appropriate action shall be taken to restore full protection or to

instigate other measures that monitor corrosion

5.6.5 Measuring equipmentOnly approved measuring equipment and techniques in accordance with the requirements of

AS/NZS 2832.1 shall be used.

5.6.6 Interference

Interference testing shall be conducted in accordance with AS/NZS 2832.1

5.6.7 Records

Records in accordance with the requirements of AS/NZS 2832.1 shall be retained for the

life of the pipeline.


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5.7 INTERNAL SURFACES

5.7.1 Mitigation audits

Where the design of the pipeline in accordance with AS 2885.1 includes the use of

inhibitors and biocides as the method of corrosion mitigation, the operating authority shall

confirm the suitability of the design on a regular basis.

Where the mitigation method is found to be unsatisfactory, the method shall be revised to

achieve the required level of corrosion control in accordance with AS 2885.1.

5.7.2 Personnel

The parties responsible for the monitoring, testing and maintenance of the internal

corrosion mitigation system shall have the requisite experience and qualifications as

approved by the operating authority.

5.8 STATIONS

5.8.1 GeneralThe following requirements apply to stations for pumps, compressors, meters, mainline

valves, pressure-regulators, odorizers, and the like.

(a) The area around stations shall be maintained in a clean and safe condition.

(b) Entries, exits, and escapes routes shall be kept free from obstruction at all times.

(c) Fences and gates shall be maintained to ensure the protection of the public and theequipment.

(d) Start up, operating, and shutdown procedures for all equipment shall be establishedand followed. The procedures shall include details of the measures required to ensure

that all equipment, including any shutdown control or alarm circuits, functions

correctly.(e) Warning signs shall be maintained to ensure their accuracy, legibility and adequacy.

(f) When deviations from the normal operating conditions that affect the safety of the

pipeline occur, corrective action shall be initiated immediately.

(g) Where determined necessary, firefighting equipment shall be kept on site and

maintained in good condition.

NOTES:

1 When the site is attended, sufficient personnel trained in the use of the firefighting equipmentshould also be in attendance.

2 AS 3788 should be considered for pressure vessel inspections.

3 The relevant sections of AS/NZS 3000 should be considered.

5.8.2 Pressure control and protective equipment inspection

All pressure control and protective equipment, including regulators, controllers, relief

valves and safety devices, shall be subjected to systematic inspection and testing in

accordance with the maintenance plan to determine if they are

(a) in good electrical, mechanical or hydraulic condition;

(b) set to function at the correct level;

(c) properly installed and protected from foreign material or other conditions that might

prevent proper operation;

(d) installed in a manner so as to prevent unauthorized operation or alteration;

(e) operating correctly; and

(f) adequate from the standpoint of capacity and reliability of operation.

Safety valves shall be maintained and tested in accordance with AS 1271.



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5.8.3 Site security

When a station is unattended, the site shall be appropriately secured.

5.8.4 Structure

Structures housing equipment containing hydrocarbons, such as compressors, pumps,valve/regulator/meter pits or buildings, instrument rooms and laboratories, shall be

inspected at approved intervals and shall be maintained in a safe condition.

The inspection shall include the following:

(a) Testing of the atmosphere in the structure for toxic and combustible vapour.

(b) Operation of ventilating equipment.

(c) Structural integrity of pit covers.

(d) Testing of any alarms.

5.8.5 Structures housing equipment

A structure that houses equipment shall be inspected at intervals determined by experience

with the equipment and the risk assessment carried in accordance with the requirements of

AS 2885.1. It shall be maintained in good condition.

The inspection shall include the testing of the atmosphere in the structure for toxic and

combustible vapour. Leaks of these types shall be located and repaired.

Ventilating equipment shall be maintained in a satisfactory operating condition. Ventilation

ducts shall be cleared of any obstruction.

A pit cover shall be examined to determine that it does not constitute a risk to the public,

and that no damage to the equipment will result from unexpected loads on the cover.

5.9 ANCILLIARY EQUIPMENT

5.9.1 General

In addition to the pipeline itself, equipment ancillary to the pipeline, and in particular the

items listed in Clause 5.8, shall be regularly maintained.

5.9.2 Valves

Valves and actuators require regular usage and maintenance to ensure they are functioning

correctly. They should be inspected at approved intervals to ensure that

(a) each valve is properly supported and that corrosion problems at support points are notoccurring;

(b) valves are secured to prevent unauthorized access and usage;

(c) valve pits are structurally sound and that corrosion on fitt ings is not occurring;

(d) valves are not leaking; and

(e) valves and actuators are fully operable.

Valves including mainline valves and the emergency hand-operated equipment of remotely

controlled valves shall be tested or operated at approved intervals to confirm operability.

5.9.3 Pipe supports

All pipe supports, for above-ground portions of lines, shall be inspected at approved

intervals. The inspections shall establish the physical condition of each support, and verifythat they are providing the required support for the pipe at that point. Where applicable, the

interface between the carrier pipe and the pipe support shall be inspected for corrosion.


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5.9.4 Ground entry locations

Severe corrosion can occur at the point where pipelines enter and leave the ground. Such

points shall be inspected, in accordance with the maintenance plan, for coating deterioration

and associated corrosion.

NOTE: The inspection intervals are dependent on the coating type applied to the line.

5.9.5 Pig trap inspection and maintenance

Maintenance of all components of pig traps (including end closure seals, bleed locks,

electrical bonds, locking rings, pig signallers and fasteners) should be undertaken just prior

to use, after painting or at approved intervals.

In addition, temporary or removable pig traps should be inspected before use for

mechanical damage (due to handling) and for evidence of corrosion.

NOTE: Quick opening closures shall be operated and maintained strictly in accordance with the

manufacturer s instructions, particularly with regard to the yoke adjustments and pressure-

warning devices.

5.9.6 Underwater pipelines

The operating authority shall have measures in place so as to remain reasonably assured

that, for underwater crossings

(a) the depth of cover, if the pipeline is buried, remains adequate;

(b) that scouring has not caused any part of the pipeline to be unsupported beyondallowable freespan length; and

(c) that there is no accumulation of debris or silt that could affect the stability and safetyof the pipeline.

In the event that the operation is not so assured, further inspections are to be undertaken.

Additional inspections shall be made following severe floods, storms or earthquakes whichcould have affected the integrity of the crossing. Corrective action should be initiated

immediately when inspection reveals an unsafe condition.

5.9.7 Tunnels, shafts and valve pits

Tunnels and shafts shall be inspected at approved intervals to confirm

(a) the structural integrity of the tunnel or shaft; and

(b) the absence of leaks in the pipeline.

Corrective action shall be initiated immediately where the necessity for such action is

revealed. A tunnel shaft or valve pit accessible by people may be a confined space. Such

entry shall be controlled by the confined space entry procedure and permit in accordancewith AS 2865.

Valve pits shall be kept free of all matter that in any way could interfere with the operation

of the valve.

5.9.8 Casings (sleeve) maintenance

Schedules for pipeline maintenance should include appropriate checks on casings and

attachments (e.g., checks for pipe to casing contacts or resistive bonds and gas detection of

annulus vents for hydrocarbon).



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S E C T I O N 6 T H R E A T M I T I G A T I O N

6.1 GENERAL

The operating authority shall implement systems to ensure that all threats to pipeline

integrity identified in the risk assessment carried out in accordance with the requirements of

AS 2885.1 are adequately addressed to r educe the level of r isk to ALARP. The

effectiveness of the physical and procedural measures implemented to mitigate all identified

risks and the corresponding risks shall be reviewed.

6.2 PIPELINE SURVEILLANCE

6.2.1 General

Pipeline surveillance shall be carried out by the operating authority to ensure a pipeline is

free from identifiable leaks and to identify any new or changed threats to the pipeline,

particularly any unnotified external interference near the pipeline. The type of surveillance

and the frequency required for safe pipeline operation varies and should be determined by

risk assessment performed in accordance with AS 2885.1 and incorporated into the safety

and operating plan. Factors to be considered in the risk assessment include, but are not

limited to, the following (see Section 4):

(a) Operation of a One-Call system.

(b) Whether the pipeline is above- or below-ground.

(c) Other forms of protec tion against interference.

(d) Activities by third parties that could affect the pipeline.

(e) Location in a built-up area.

(f) Locations close to environmentally sensitive areas.

(g) Provision of a leak-detection system.

(h) Regularity of use.

(i) Nature of the fluid carried.

(j) Design and operating pressure and temperature.

For a pipeline that is not regularly used, a patrol at frequent intervals may be maintained

during use only, provided the line is isolated from sources of pressure when not in use. An

annual patrol is required as a minimum.For a pipeline in regular or continuous use and provided the observer can clearly identify

the pipeline and observe all the surveillance criteria (see Clause 6.2.2), the type of

surveillance shall be by at least one of the following:

(i) Foot patrols.

(ii) Vehicle patrol.

(iii) Aerial patrol.

(iv) Watercraft for underwater pipelines.

6.2.2 Patrol of route

The route shall be patrolled and inspected in an approved manner at approved intervals as

detailed in the safety and operating plan, and whenever it is considered that damage or

threats to the integrity of the pipeline may have occurred or may be expected to occur.


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The route shall be accessible to authorized personnel, and clear access to valve stations

shall be maintained.

Corrective action shall be initiated immediately a condition requiring such action is

detected.

Particular attention shall be given to excavation, boring activities, including the use of anauger, and drains or ditches that are maintained and cleaned by an independent party.

Surveillance criteria shall include the following:

(a) Variations to surface conditions such as erosion or earth movement.

(b) Indications of leaks such as dead vegetation or evidence of liquid.

(c) Construction activity or evidence of impending construction activity on or near theroute.

(d) Impediments to the access to the route, valve stations, pressure regulator stations,compressor stations, pump stations, cathodic protection sites, communication

installations, and the like.

(e) Deteriorating condition, visibility, adequacy and correctness of route markers andsigns installed in accordance with the relevant requirements of Clause 6.3.

(f) Security of sites and evidence of unauthorized entry.

(g) Any specific action identified in the risk assessment.

(h) Any other factors affecting the safety and operation of the pipeline.

(i) Any factors likely to change the risk assessment such as urban encroachment and newdevelopments.

The person conducting the patrol shall

(i) be issued with written patrolling procedures;

(ii) be appropriately trained in the procedures;

(iii) know the extent of the pipeline easement and the location of the pipeline;

(iv) be in radio/telephone communication with the pumping station/control centre; and

(v) maintain a patrol log.

All surveillance patrol records shall be retained for the minimum period specified in the

record management plan.

6.3 PIPELINE MARKING

Signs shall be maintained along the route so that the pipeline can be properly located and

identified from the air, ground, or both, as appropriate to each particular situation, as

identified in the risk assessment.

Maintenance of pipeline marking shall ensure the following:

(a) Legible signs are maintained at spacings as per the design documentation and in anycase at the minimum requirements specified in AS 2885.1.

(b) Signs at the landfall of submerged crossings or submarine pipelines shall be visiblefrom a distance of at least 100 m on the water side of the landfall.

NOTE: Illustrations of typical marker signs are shown in Appendix E.



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Maintenance of pipeline marking shall also include mainta ining or adding

(i) signs or other markers at each change of direction, at each side of permanent

watercourses, at each side of road and rail crossings and at crossings of each property

boundary;

(ii) signs at all above-ground facilities; or

(iii) any other signs that identify the location of the pipeline.

NOTE: Signage is intended to provide a visible indication of the existence of a pipeline in the

vicinity. It is desirable to maintain a line of sight so that from any point on the right of way a sign

is visible.

6.4 EXTERNAL INTERFERENCE PREVENTION

6.4.1 General

The operating authority shall take all reasonable steps to inform people and organizations

that may in any way rely upon the safety of the pipeline as follows:

(a) Informing the appropriate authorities and other relevant bodies of the hazardousproperties of the fluid and the effects of any accidentally discharged fluid on the

safety of the public so that, in the event of an emergency, prompt joint cooperative

action can be taken.

Procedures for cooperative action shall be established and maintained in the

emergency plans required by Clause 2.2 and Section 4 of this Standard.

(b) Informing landowners and other occupiers of land through which the pipeline passesof the methods of recognizing threats to the pipeline and an emergency situation.

They should be supplied with 24 hour contact telephone numbers of the appropriate

responsible persons or organizations to be notified in the case of an emergency.

Warnings should be issued concerning the dangers of interference with the pipelineand its appurtenances.

(c) Operating authority staff visits, at approved intervals, to provide landowners andother occupiers of land through which the pipeline passes with information to ensure

that their activities do not endanger the pipeline and its appurtenances.

To ensure the integrity of the pipeline and the safety of the public and the environment, it is

critical that identified groups such as land use planners, developers, property and service

designers, owners and operators, construction organizations, excavators, drillers and borers

and the general public take into account the presence of the pipeline in their intended

activities. Appropriate regular communication with these and with the relevant authorities is

required to raise and reinforce awareness of the presence of a pipeline and the constraints

with respect to the use of the land on and near the pipeline.

The operating authority should identify all such parties on the basis of the requirements

identified in the risk assessment and establish a liaison program with these groups, to

ensure that, preferably in the concept stage, any changes in planning development or similar

activities are advised to the operating authority.

Appropriate consultation between the parties at this stage will ensure minimal impact on

pipeline operations.

NOTE: Where it is not possible to personally contact the identified parties consideration should

be given to providing a package of information and contact details to the parties.

Third parties responsible for development work should be made aware that certain

developments near the pipeline could require additional protection, as detailed inAS 2885.1.

The operating authority shall include the constraints set out on land adjacent to the pipeline,

when communicating with the relevant parties.


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6.4.2 Access to the pipeline

The requirement for access to the pipeline easement shall be assessed. Where access is

determined necessary, the easement shall be maintained to allow appropriate access by

pipeline personnel and authorized contractors.

6.4.3 Prohibition of buildings near the pipeline

The operating authority should have systems in place to ensure that no building or structure

shall be allowed within a safe distance from the pipeline, as determined by the pipeline

design and the risk assessment. Any parties intending to construct or erect a building or

structure within this zone should first consult with, and obtain the approval of, the operating

authority and, where an easement exists, the approval of the authority administering the

easement.

6.4.4 Vegetation on and near the pipelin

pipeline maintenance

Documents

Transcript of pipeline maintenance