Preliminary work that stops short of physical construction can continue on the hotly contested Keystone XL pipeline project while a court-ordered additional environmental assessment proceeds, Montana District Judge Brian Morris ruled on Thursday.

The decision enables TransCanada Corp. to continue with planning, engineering, shipper contract confirmations, and acquisitions of land rights, equipment and permits while the U.S. State Department updates its project approval.

The judge granted the partial go-ahead after TransCanada informed the court that an order earlier this month for further review would delay construction by a year if it was interpreted to mean all activity had to stop.

TransCanada estimated that a one-year total suspension of the decade-old oil export project would cause substantial harm, including a $949 million loss of company earnings and postponement of 6,600 jobs in the United States.

The successful plea to let construction preliminaries continue confirmed industry determination to build the $8 billion, 1,179-mile pipeline designed to deliver 830,000 b/d of Canadian oilsands production.