Tolmount Gas Pipeline

Appointed to design and build both the temporary and permanent works associated with the build of a drive shaft and a 146m long microtunnel, as part of the Tolmount Gas Pipeline Project.

Tunnelling and Underground Works Shaft Sinking
Sector:
Energy
Client:
SAIPEM
Main Contractor:
JGL
Location:
Yorkshire
  • This project was entirely resourced and managed with our own internally owned Group assets,
  • The Iseki machine was recovered form a cofferdam within the foreshore under tidal conditions,
  • The team worked though tough conditions and championed our LIFE safety values & behaviours, with no major incidents.

Contact usTo hear about our experiences and how we can help you.

Project Overview

Joseph Gallagher was appointed to design and build both the temporary and permanent works associated with the original scope, which involved constructing a permanent drive shaft and a 146m‑long microtunnel as part of the Tolmount Gas Pipeline Project.

The shaft was a 21m deep jacked caisson 5.5m id. The microtunnel was 1.2m id and 146m in length.

Challenges

Working within Centrica Storage Limited’s (CSL) live gas‑handling facility - receiving and processing gas from North Sea pipelines - presented significant logistical challenges and required the team to adapt to procedures outside their usual operating environment.

The Project Manager ensured all team members fully understood what was expected through regular briefings and opportunities to spend time with CSL representatives. Adaptations were required to both diesel and electric plant, including the installation of spark arrestors and Chalwyn valves. JGL worked closely with SAIPEM during mobilisation to understand the terminal’s processes and procedures.

This collaborative approach helped establish a strong working relationship from the outset, enabling documentation approvals and the issue of multiple work permits within a week - no small achievement within a live terminal environment.

Added Value Contributions from JGL

The team made additional efforts to liaise with CSL and their environmental representatives to fully understand procedures and ensure no delays occurred within the terminal. CSL representatives were invited to spend time with the site team to observe the shaft‑excavation process, helping to streamline these new requirements. Wastewater was processed through a filtration system prior to discharge. The treated water was collected within CSL’s holding pond before final release.

 The tunnelling works reused the water generated during excavation by directing it into two Iseki settlement tanks, removing the need to source additional water.

This recycled water was also used for grouting the shaft annulus, further reducing resource consumption.

JGL at Tolmount Gas Pipeline Project

Contact us

To hear about our experiences and how we can help you.

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