The workers say the consolidations have cost jobs, delayed mail service, and even endangered some postal workers.

"As they consolidate, they're cutting back jobs, but they also say they need to pick up the pace and get more mail out at a faster rate. As you turn the machines up, you can't keep up. We do see the injuries," said Scott Adams from the Postal Workers Union.

Adams says the opening of a big regional service center in Scarborough is having an impact on local mail, because workers there are now sorting mail from as far away as Portsmouth and Boston.