The Globe and Mail reports in its Thursday edition that the expanded Trans Mountain oil pipeline system marked its official start on May 1. The Globe's Emma Graney writes that the goal of the Trans Mountain Expansion (TMX) is to open overseas markets for Canadian oil and remove a price discount that had existed for years because of an overreliance on exports to the United States. Plans for the $34-billion project, which runs 1,150 kilometres from Edmonton to Burnaby, B.C., launched more than a decade ago. TMX saw numerous court challenges and protests, including many around environmental concerns. Those critiques have not disappeared -- particularly when it comes to concerns about vastly increased numbers of oil tankers steaming past Vancouver's busy harbour. The pipeline was still being filled on Wednesday, a process that began on April 16 and is expected to be completed within the next few weeks. As of April 30, the expanded pipeline was 70 per cent full by volume, and 69 per cent complete by distance. The final, so-called "golden weld" of TMX was on April 11, in B.C.'s Fraser Valley between Hope and Chilliwack. The region has some of the most difficult terrain and sensitive areas along the entire pipeline route.