Pipeline Decommissioning

What happens when a pipeline is shut down?

In Canada, there are more than half a million kilometres of oil and gas pipelines that are in operation and more than 50 per cent of those pipelines are located in Alberta. With the amount of pipelines running throughout Canada it is important for all stakeholders, including oil and gas companies and affected landowners, to understand that pipelines have a lifecycle and how each lifecycle phase may affect them. Throughout a pipeline’s lifecycle the owner/operator of the pipeline will make decisions about the pipeline’s level of use. When a company decides to stop using a pipeline, replace a pipeline, or re-route a pipeline, questions can surface about what happens to the old pipeline and the effects this would have on landowners.
Each province has its own regulatory agency with a set of specific requirements for pipelines but if a pipeline crosses provincial borders then it falls under the jurisdiction of the National Energy Board (NEB). Under the NEB there are three different options that a company can choose from when they decide to stop using a pipeline: deactivation, abandonment or decommissioning, all of which require NEB approval.
The NEB refers to deactivation as “to remove temporarily from service”. More specifically, the NEB goes on to state that in practice it is acceptable that portions of pipeline that are in a deactivated state:
• Never return to service,
• Can remain in a deactivated state for an unspecified amount of time, or
• Can eventually be abandoned.
An application for deactivation likely would be subject to conditions. It will also likely require that the company completes periodic status reporting for the deactivated line. The NEB also suggests that it would be beneficial for a company to consult with stakeholders regarding a deactivation. These consultations should address any questions or concerns that stakeholders may have about the deactivation. These concerns can relate to the protection of the stakeholder’s property, safety of people and protection of the environment.
 A company also has the option to reactivate a deactivated line. The company must file an application with the NEB that explains the need for reactivation. The application must also have a description of the proposed activities to reactivate said pipeline and it must also identify all potential impacts.
The NEB consistently holds companies accountable to its stakeholders and the public during the construction, post-construction, operation and abandonment of a pipeline’s lifecycle. The term ‘abandonment’ can sound ominous and make it seem as though a company can simply leave a pipeline with no accountability on their part. The reality is quite the opposite.
When a company is applying for abandonment it is deciding to permanently stop using a pipeline and wants leave to “abandon the operation of a pipeline”. The abandonment phase of a pipeline often starts after a company has already deactivated the line. Once a company decides to abandon a pipeline it must apply for abandonment of the pipeline and of the connected facilities.
When abandoning a pipeline, reclamation criteria need to be agreed upon by all affected parties including the owner/operator, regulatory authority and the landowners prior to any commencement of field activity. This reclamation program is designed to ensure that the right-of-way land surface condition is returned to the state it was in prior to beginning of abandonment activities. If circumstances permit, the right-of-way land surface condition should be returned to the condition that it was in prior to any pipeline installation.
There are two options for the abandonment of a pipeline. It can either be removed from the ground or it can be left in the ground after it has been cleaned and treated. The NEB considers land use management to be the most important factor to think about when deciding if a pipeline section should be removed upon abandonment or remain in place. To make this decision it is important to know what the land is currently used for and what potential uses it has along the pipeline right-of-way. A company must also consult and gather input from all appropriate sources including any affected stakeholders to support the decision to abandon in place or through removal. It is important to consider the potential uses of land because abandoning a pipeline in place could have an effect on future development. It could cause issues for excavation for foundations, pilings or ongoing management practices such as installing sub-drains or deep ploughing.
If a pipeline is to be abandoned in place, key environmental protection measures should be considered. For example, there should be minimal disruption to future or ongoing land management activities and a complete cleaning procedure should be documented. Any spills or contaminated sites should be cleaned to prevailing regulatory requirements and a revegetation strategy should be put in place to achieve pre-abandonment conditions while keeping soil stability and erosion control as a priority. A monitoring program should also be implemented in a way that is acceptable to all affected parties to ensure a process to complete remediation.
The NEB requires that all abandonment applications have a public review process, which can be oral or written. Like deactivation, if the NEB decides to allow abandonment it may be subject to conditions. These conditions normally need to be met before abandonment is complete. When a company has met all of the conditions ordered by the NEB and the risk to public safety, property and environment is considered to be at an acceptable level, the NEB oversight ends. However, the NEB may still intervene if necessary.
After an owner/operator has abandoned a pipeline, it still has many responsibilities. The owner/operator is responsible for making sure the right-of-way and any facilities that were left in place stay free of any problems that could be associated with the abandonment. The owner/operator should include a right-of-way monitoring program in the post-abandonment plan.
Abandoning a pipeline and decommissioning a pipeline have similar definitions, however there is a difference. A company can decommission a particular line and by doing so it is not discontinuing service throughout the rest of the connected lines. A pipeline that is part of a larger series of lines can be decommissioned to no longer transport hydrocarbons while the rest of the series of lines continue to provide service.
For further information about deactivation, abandonment and decommissioning please visit the NEB website:http://www.neb-one.gc.ca/clf-nsi/index.html

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