The steps include consolidating up to 140 locations beginning this summer through February 2013, the organization stated.
The Harrisburg Pike distribution center in Manheim Township, Lancaster County, is the only one in the midstate listed in the locations to be consolidated. It had some operations shifted to the Harrisburg facility last summer.
"We simply do not have the mail volumes to justify the size and capacity of our current mail processing network. To return to long-term profitability and financial stability while keeping mail affordable, we must match our network to the anticipated workload," said Patrick R. Donahoe, postmaster general and CEO of the service.
The operations of the distribution center are expected to be consolidated to Harrisburg in January, said Ray Daiutolo, USPS spokesman for Central Pennsylvania.
The bulk mailing entry and the retail post office in the Harrisburg Pike facility will remain open, though they might be moved to a smaller location in the future, he said.
There are about 300 employees at Lancaster's distribution center, including managers for the location, he said.
When asked if the staff will be laid off, Daiutolo said, "It's too early to say; we will comply with the respective bargaining agreements of each of the unions."
The service said 48 locations will be consolidated during the summer, with about 5,000 employees receiving notifications next week related to the efforts.
"Due to the volume of high-priority mail predicted for the election and holiday mailing seasons, no consolidating activities will be conducted from September through December," the release stated.
The first phase of consolidations will reduce the postal service's work force by about 13,000 employees and provide cost savings of about $1.2 billion annually, according to the release.
"Given that the Postal Service is currently projecting a $14 billion net loss in (fiscal year) 2012, and continuing annual losses of this magnitude, we simply cannot justify maintaining our current mail processing footprint," Donahoe said.
The second phase of consolidations will begin in February 2014 for 89 facilities, unless the service's circumstances change, according to the release.
Total consolidation is expected to offer $2.1 billion in annual cost reductions and a workforce reduction of about 28,000 employees, according to the release.
Editor's note: This story has been modified from its previous version to include comments from Ray Daiutolo, USPS spokesman for Central Pennsylvania.