They’re digging up dirt around the midcoast.

Camden Harbor is being dredged for the next six to eight weeks, and the dredging of Rockland Harbor is just around the bend.

The nearly $800,000 Rockland project will begin during the second week of December, said Stephen Durrell, project manager for Prock Marine, on Thursday.

The contract package is $1,647,500 for removing silt and other materials from Rockland and Camden harbors as well as the Union River in Ellsworth.

The Ellsworth project, which involves removal of 7,000 cubic yards of bottom material, is under way and should wrap up in a couple of weeks. The cost: $471,500.

Prock Marine workers began dredging Camden Harbor on Monday. The price tag on that portion of the contract is $396,250. The job entails digging up some 17,000 cubic yards.

The Rockland project is the largest, involving the extraction of 51,000 cubic yards of silt and other matter. The dredging will cost $779,750, Durrell said, and will take an estimated 12 weeks to complete, depending on the weather.

The number of dredging projects varies from year to year, he said, but this year there were more than usual.

Last year, the Rockland-based marine contractor dredged Little Harbor in Rye, N.H., and this past summer, it had workers dredging in Quincy, Mass.

The Prock crew that will dredge Rockland Harbor has been on another job and has not been home since January, he said.

Rockland Harbor Master Chad DeLima said Rockland Harbor has not been dredged for about 25 years.

The U.S. Army Corps of Engineers – using federal funds – pays for the dredging, which will encompass the channels from Rockland Breakwater Light toward the U.S. Coast Guard pier. The channels branch off to Prock Marine and the edge of the Rockland Fish Pier and near the corner of MBNA and the public landing, as well as the O’Hara fish pier.

The channels will be dredged to 18 feet in some spots and 14 feet in other areas, DeLima said.

The dredged material is taken three miles out in Penobscot Bay and dumped, he said.

The Prock crews will work around the clock five days a week until the job is completed, Durrell said. The six-person crews will work 12-hour shifts from 6 a.m. Mondays to 6 p.m. Fridays, he said.

The corps is responsible for maintaining the depths in federal channels, he said.

The dredging will not make the channels any deeper than they should be, Durrell said, and so the project will not allow larger vessels to access the harbor. The sludge at the bottom of Rockland Harbor has been tested for contaminants by the corps, he said, and there are no environmental problems.