A year-end completion target can be hit after Coastal GasLink Pipeline Ltd. construction hit the 90% completion mark on its 670-kilometer (400-mile) natural gas pipeline linking Montney Shale production to the Shell plc-led LNG Canada liquefied natural gas export terminal, according to the company.

All but 48 kilometers (29 miles) of pipe have been laid in sometimes hotly contested native areas on the route across mountains and muskeg swamps in northern British Columbia. Up to 6,000 contract workers are to be used to complete the most difficult, technical parts, with completion on target for December.

A Shell official in June said the LNG Canada export project in Kitimat, BC, was “more than 80% complete and on track with the first cargo by the middle of the...