BILLINGS, Mont. (AP) — Representatives of Exxon Mobil Corp. were scheduled to appear at a Wednesday hearing before federal regulators to protest $1.7 million in penalties for a Montana oil spill.

A U.S. Department of Transportation spokesman said the closed-door hearing would be held in Denver.

The civil penalties announced in March stem from a 2011 pipeline break that spilled an estimated 63,000 gallons of oil into the Yellowstone River near Laurel.

Federal regulators charge that Exxon failed to take steps to guard against erosion caused by flooding. They also say the company did not close an upstream safety valve quickly enough, making the spill much worse.

Exxon representatives maintain that the company took proper precautions. They want the penalty reduced.