Some mail that was being handled at the U.S. Postal Service’s processing facility in Hampden is now being sorted in Scarborough two hours to the south.
Postal officials say the change is part of an effort to improve efficiency and reduce costs.
But others say the change is delaying some mail delivery and could result in worker layoffs.
Richard Reed Jr., president of the Bangor Area Local 536 of the American Postal Workers Union, wrote a letter to a number of postal customers indicating that the switch will adversely affect mail delivery.
Senator Susan Collins has written a letter to U.S. Postmaster General John Potter saying the change could mean mail delays throughout central, eastern, and northern Maine.