LNG Storage Plant Hydrotest Project
Project Highlights
  • Provided MAOP reconfirmation for ~ 2 miles of transmission pipeline

  • Upgraded pipeline features in need of MAOP validation via replacement

  • Coordinated pipeline feature replacements at 7 locations under a single flow interruption plan

Through a Digs Project Management Office (PMO), GTS provided program and project management as well as MAOP Reconfirmation, design, and field engineering services to execute a hydrotest of two segments of natural gas transmission pipeline. The pipelines tested were approximately 2 miles in length and were located between an existing custody transfer point and a client’s LNG storage plant, located in a metropolitan area. Successful execution of the project involved coordination with an interstate pipeline operator to conduct construction activity and to develop and implement a flow interruption plan.

By completing the project, the client met several key requirements of their TIMP plan and integrity verification program. The most critical and time sensitive landmark was achieved, as the hydrotest served as an integrity assessment to meet federal compliance requirements as prescribed by 49 CFR 192. Additionally, the test provided an updated and current pressure test record in accordance with 49 CFR 192 subpart J requirements, and as such the pipelines’ MAOP was then reconfirmed.

During the planning and design stage of the project, GTS identified several locations along the existing line that required MAOP validation. Investigation digs at these locations were designed, scheduled, and executed in conjunction with the isolation. Based on the findings, GTS recommended replacing and upgrading pipeline features, including 3 elbows and an insulator, all located at different locations along the pipeline. Construction activity for the MAOP replacements was executed while maintaining the project schedule.

Also involved, were two separate cutout and replacement repairs along the line. One replacement needed the removal of a pipe section with weldovers and gouges, removing damage that resulted from the use of unsuitable backfill material. The other involved cut out and replacement of over 20 feet of heavily corroded pipe adjacent to the station and custody transfer point.

The project was successfully executed through coordinating efforts with the stakeholders as well as multiple contractors, subcontractors, and specialty vendors. GTS completed the project in time to meet the compliance deadline and the client was able to restore service for commercial, industrial, and residential customers ahead of the cold winter months.