The TGP is a natural gas transmission pipeline system that extends from Longford in Victoria, across Bass Strait to Bell Bay in north-east Tasmania. Additional onshore pipelines extend from Bell Bay to Port Latta in north-west Tasmania and to Bridgewater in the south. The TGP transports sales quality Natural Gas from Longford, Victoria to Tasmania. TGP Natural Gas comprises largely methane (approximately 91.14%) and ethane (5.21%) and is dry and free from significant impurities under normal operating conditions. Other components include carbon dioxide (2.26%), nitrogen (0.74%), propane (0.5%) and minor quantities of oxygen, butane, pentane and hexane (in quantities less than 0.1%).
The TGP is an operating pipeline transporting natural gas from Victoria to Tasmania and, therefore, there are no daily activities on the pipeline itself apart from continuous monitoring of pipeline flows and pressures by the Control Room.
Surveys of the pipeline, to assess pipeline integrity and any maintenance requirements, are undertaken on a periodic basis and occur approximately every 2 to 5 years.
Consequently, temporary facilities are only on location during subsea survey and emergency repair works if, and when, they arise.