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October 3, 2019
October 3, 2019


The increasing complexity of mandatory pipeline integrity programs, together with increased governmental rules and regulations, has led many pipeline operators to outsource inspection and integrity services to independent service providers that have a proven track record of performance. Independent inspectors assist the pipeline operators with performing multiple tasks associated with documentation and project oversight of their asset integrity programs and related construction, inspection, maintenance and repair activities. Independent inspectors generally operate as an extension of the pipeline operators’ management and employees where additional experienced personnel are needed to perform pipeline inspection and integrity services.

Pipeline Inspection

Every mile of pipeline is susceptible to risks such as internal and external corrosion, cracking, third-party damage and manufacturing flaws. To mitigate the risk of environmental damage and enhance public safety, government regulation mandates that pipeline operators assess the safety and integrity of their pipeline infrastructure on a recurring basis. PHMSA guidelines identify the minimum standards for evaluating the integrity and safety of pipeline assets and facilities by requiring certain periodic inspections.

Integrity Management

The potential fines for non-compliance at both federal and state levels and the excessive unplanned costs associated with spill remediation, all of which can negatively impact a pipeline’s performance, pipeline operators are compelled to develop and implement comprehensive integrity management programs. An integrity management program is a set of safety management, analytical, operations, and maintenance processes that are implemented to assure that operators provide protection for locations where a pipeline failure could have significant adverse consequences. An integrity management plan should also specifically address ‘‘high consequence areas,’’ or HCAs. HCAs include those areas that are unusually sensitive to environmental damage, that cross a navigable waterway or that have high population density.

The elements of an integrity management program include:

  • Maintaining full documentation of the pipeline infrastructure for the lifespan of the asset;
  • Identifying all locations where a pipeline failure might impact an HCA;
  • Developing a risk-based plan to conduct integrity assessments on the portions of the pipeline that could affect an HCA;
  • Integrating the assessment results with other relevant information to improve the understanding of the pipe’s condition;
  • Repairing defects identified through the integrated analysis of the assessment results;
  • Conducting a risk analysis to identify the most significant pipeline threats in segments that can affect HCAs (for example, pipe defects, corrosion and excavation-induced damage);
  • Identifying additional measures to address the most significant pipeline threats, including actions to prevent and mitigate releases and can go beyond repairing the discovered defects;
  • Evaluating regularly all information about the pipeline and its location-specific integrity threats to determine when future assessments should be performed and what methods should be selected to conduct those assessments;
  • Documenting compliance with PHMSA and other government or regulatory authorities;
  • Evaluating periodically the effectiveness of the integrity management program and identifying improvements to enhance the level of protection, generating safety programs and emergency response plans and communicating a set of best practices to personnel involved in the construction, operation, maintenance and repair of its pipeline infrastructure.

In-line Inspection

Pipeline inspection primarily applies non-destructive examination, or NDE, methods to ensure asset integrity. NDE is the examination of pipeline assets without impacting the future usefulness of the assets. The examination method also allows for minimum operational interruption of the assets undergoing inspection.

A common device used in the NDE of pipeline infrastructure is a pipeline inspection gadget, or pig. A pig is a cylindrical device that is introduced into the pipeline and is transported through the pipe typically without interrupting operations. Pigs perform a variety of functions inside the pipe, including debris and condensate cleaning, plugging, product separation, hydro testing, dewatering and inspection. Inspecting pigs, referred to as in-line inspection pigs, or smart pigs, contain testing devices and collect information while traveling through the pipeline.

Pig inspection can take days to weeks depending on the length and condition of the pipeline being inspected. While the pig is traveling through the pipeline, inspectors must track the location of the pig and catalog data from the pig. The results of pig testing are used by the pipeline operator to determine anomalies and sections of the pipeline targeted to undergo further examination