Pipeline Construction at a Glance

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1 Pipeline Construction at a Glance

2 Pipelines are the safest, most efficient and environmentally responsible way to transport natural gas and petroleum products, and TransCanada has an industry-leading safety record. From design and construction to operations and maintenance, safety is our top priority.

3 About this Guide Building and operating safe and reliable energy infrastructure - it s what we do and have done well for over 65 years. Our energy infrastructure assets are essential to millions of people across North America who rely on the energy we deliver every day to heat their homes, cook their food and fuel their vehicles. Our pipelines are designed, constructed and operated safely and reliably every day. Our priority is to make sure our employees and contractors make it home safe and that our neighbours see us as a responsible and trusted community member. We recognize that no safety-related incidents are acceptable and we will not be satisfied until we reach our goal of zero incidents. This book outlines the steps and processes involved in building a pipeline. All stages of pipeline construction are completed by TransCanada contractors that must meet our strict qualifications and standards. 1

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5 Route Selection One of the most important elements when designing a new pipeline is determining the route the pipeline will take. Where possible, TransCanada tries to minimize the route length and use existing pipeline right-of-ways or other linear disturbances that have previously established corridors, which will minimize the social and environmental effects. If a new right-of-way must be established, TransCanada works with landowners, stakeholders and Indigenous communities to ensure that valuable information is gathered and incorporated into the final route. 3

6 Pre-construction Activities Three types of field surveys are performed prior to the various stages of pipeline construction. These surveys are used for project permitting and pipeline design. Civil surveys are conducted to locate facilities including the construction corridor and pipe centre line, work area boundaries, sensitive and/or environmental resources and any issue or resource that requires geo-referenced data. Environmental field surveys are done to collect and identify unique environmental characteristics that exist along the proposed pipeline route, influence the pipeline routing decision making process and support the Environmental Impact Assessment for the project. 4 Geotechnical surveys are used in pre-determined locations to collect geological and soil data that support pipeline construction analyses.

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8 Pipe Storage and Transportation TransCanada safely operates more than 72,000 kilometres (44,500 miles) of pipelines in North America. These pipelines deliver the energy that North Americans rely on each day. 6

9 Pipe is stockpiled at various locations near the right-of-way that enables the contractors to complete the construction work in a safe, orderly and efficient manner. 7

10 In Business to be a Good Neighbour. It takes more than energy to power a community. It takes a connection. A community spirit fostered by those willing to go the extra mile for their neighbours both down the road and across North America. The same connection we share with our 70,000 landowner and Indigenous neighbours. 8

11 Clearing and Grading Once surveying is complete, various types of equipment is used to clear the right-of-way. All trees and brush will be removed. A working surface is then prepared by stripping and storing the topsoil layer and grading the subsoil to create a safe work surface. 9

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13 Topsoil Stripping Our contractors separate and conserve the topsoil removed from the right-of-way so it can be replaced once construction is complete. Topsoil conservation ensures the land is returned to an equivalent environmental capability and productive capacity upon completion of the project. 11

14 Trenching and Ditching A trench is dug along the right-of-way using backhoes and other specialized machinery. Pipelines are buried underground to a depth meeting regulatory requirements and best management practices to protect them from disturbance while operating. 12

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17 Stringing and Field Bending Stringing is the process of placing the pre-coated pipe next to the already dug trench. Depending on the terrain and route of the trench, the pipe may be bent using special machines to accommodate for these changes. 15

18 Front-end Lineup TransCanada has become a partner of choice for the large-scale energy infrastructure North America requires because of our strength and expertise in stakeholder and Indigenous relations, engineering, project management and operational excellence. 16

19 Once bent to the appropriate shape, the pieces of pipe are then lined up tightly with one another. 17

20 Pipeline Welding Once the segments of pipe are lined up, welding will commence. Various welding techniques and sophisticated technologies are applied to weld the pipe together in one string. A clamp is used to secure joints of pipe together to ensure proper alignment of welding surface. Each connection is inspected to meet strict safety and quality assurance requirements. 18

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23 Weld Inspection Throughout construction, all welds are checked by an x-ray or ultrasonic process to verify each weld is sound. Weld testing provides sensitive and accurate inspection of the pipe welds and achieves a high degree of certainty over the integrity and safety of the pipeline. 21

24 Coating Field Welds, Inspections and Repairs of Coating The surface of the pipeline is coated for protection. Where the pipeline has been welded, a liquid bond epoxy is applied which helps protect the weld. After coating, a technique called JEEPING is used to detect chips or flaws in the coating and if required, a new coat is applied to the affected area. 22

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27 Lowering and Tie-ins Once the pipeline has been welded together it is lowered into the trench using a series of machines called sidebooms. Before the pipe is lowered, the ditch is carefully inspected to ensure it is free of rocks. 25

28 Pad and Backfill The trench is backfilled with the original subsoil and topsoil to cover the pipeline. In certain conditions where the terrain is rocky, padding may be required to protect the pipeline coating. 26

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31 Testing and Inspection Once the trench is backfilled, additional testing is performed. The first is known as hydrostatic testing. Hydrostatic testing is used to verify the integrity of the pipeline. Water is placed into the pipeline and pressurized to a level higher than the level the pipe will experience during regular operation. If a leak occurs during testing, TransCanada will replace the affected section of pipe. Once operational, as part of our pipeline integrity management program, in-line inspection or pigging is used as well. Pigging is a process that looks for any locations where pipeline irregularities may have occurred. Specialized internal inspection devices called smart pigs travel through the pipeline collecting data. The data is then analyzed to determine if there are areas of concern that require further investigation. TransCanada also conducts investigative digs based on the data analysis from pigging and other information. Sections of pipeline are excavated to investigate their condition and to ensure integrity. Detailed engineering assessments are used to determine if and when repairs are required. 29

32 Cathodic Protection A very low voltage electrical current called cathodic protection is applied to the pipe. The applied current protects the pipe from corrosion as well. The cathodic protection system is monitored on a regular basis to ensure proper operation. 30

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35 As-built Survey Depth of cover surveys are used once the pipeline has been placed in the ground. TransCanada uses cover surveys to investigate areas that are suspected to have wind or water erosion that may reduce the depth of ground cover over the pipeline. This helps to ensure the integrity of the pipe is maintained. 33

36 Before Clean Up and Reclamation The final step of construction is reclamation of the right-of-way. Great care is taken to return the land along the pipeline right-of-way to the original condition, use and biological diversity that existed prior to construction. Near David City, Nebraska Spread 5B construction Photo taken June 15,

37 After Near David City, Nebraska After restoration Photo taken August 25,

38 Monitoring our Operations The entire pipeline transmission system is monitored 24 hours a day by highly trained TransCanada employees from a computerized control centre. This is one of the many ways TransCanada is able to closely monitor conditions along the pipeline to ensure it is operating safely for the public, our employees and the environment. 36

39 TransCanada s pipelines are monitored 24 hours per day, seven days a week by highly-trained staff from the Operations Control Centre. 37

40 Contact us at: TransCanada October 2015