As recent Associated Press stories pointed out, getting a passenger train to run from Boston to Maine has proved more difficult than almost anyone imagined. The seven-year delay has hurt this state economically and environmentally and could continue for years.

The concept, proposed in the late 1980s by Train Riders Northeast, was simple enough. Run an Amtrak passenger train from Portland to North Station in Boston and connect Maine to the rest of the nation’s rail line. There was some initial struggle over getting from the north to south stations in Boston and further questions about who would pay for track improvements, but these issues were addressed in the early years. What has delayed the trains is not logistical but legal.

Guilford Transportation of Massachusetts owns 78 miles of rail between Portland and Plaistow, N.H., on which the Amtrak trains would ride, and has been in dispute with Amtrak over two questions. What defines the costs of services that Amtrak would owe to Guilford, and what percentage of liability would each entity cover? Amtrak has offered to assume 80 percent of the liability; Guilford wants it to cover 100 percent.

After years of waiting for the trains to get moving, Gov. Angus King last summer brought the two sides together in a marathon session to try to settle these issues. Nothing doing. The federal Surface Transportation Board has stepped in to try to solve the problem and is expected to rule next month. Such a decision is overdue.

Both sides in this disagreement have legitimate arguments. What is disappointing is that, given seven years, they could not have come to a compromise. Amtrak has successfully negotiated similar issues many times before to place trains on other rails, they should be able to do the same thing here.

Maine has been trying mightily to build its tourist base, and its success can be measured in the increased traffic on its roads, especially in Southern Maine. Giving vacationers and tourists another option might not solve the turnpike congestion, but it will make getting to and from Maine more enjoyable for many people. Trains also are a less-polluting way to travel, which is important considering the Environmental Protection Agency’s tougher air-pollution standards.

Connecting Maine by passenger rail to the rest of the nation is important to the state’s long-term prosperity. Though late, intervention by the Surface Transportation Board could bring welcome relief on this issue.