The railroads have been on the defensive this week after they were forced to pay a $10.8 million fine for illegally storing rail and container traffic in their storage facilities, and the Department of Transportation’s inspector general has said the agency may have done something to help prevent such incidents in the first place.

The rail industry is already facing a record backlog of over 5.8 billion railcars and containers, and more than $100 billion in costs from fuel, maintenance, and repairs for aging and damaged railcars.

President Trump has threatened to pull the plug on a $1 trillion transportation bill if it doesn’t pass Congress by the end of the month, which would be a big blow to the rail industry.

The rail and truck industries are also in the midst of a series of lawsuits, with the Department for Transportation saying it’s reviewing whether the government is acting correctly when it decides to award contracts to railroad companies.

The department has also been investigating whether rail companies were using a federal waiver program to cover costs for construction of the Trump administration’s proposed border wall.