The new pipeline will be called Yellowhead Mainline and is expected to have the capacity to deliver one billion cubic feet per day of natural gas.

When a shortage of ethane developed, Nova split the supply between its two crackers and the one shared with Dow, a strategy that Dow argued was in violation of Nova's obligation to keep its ethane cracker running at capacity.

Two dams failed this week upstream from a major chemical plant in Michigan. Years of cleanup at the toxic site may have been undone, experts fear.