The Port of Seattle has violated a federal permit by dredging more sediment from two harbor sites than allowed by the Army Corps of Engineers...

The Port of Seattle has violated a federal permit by dredging more sediment from two harbor sites than allowed by the Army Corps of Engineers.

The corps confirmed the overdredging Friday and has moved to a 30-day fact-finding period to determine whether penalties are warranted.

The Port excavated at two sites so it can relocate cruise ships from an area south of downtown Seattle to Terminal 91 near the Magnolia Bridge. The Port reported to the corps last month that its contractor, General Construction, had dug up more muck than permitted.

A spokeswoman for the corps said the Port exceeded its dredging permit by 1,348 cubic yards, the equivalent of about 115 dump trucks. The material was deposited back into the bay, as is allowed.

A Port spokeswoman said the problem might have been caused by the contractor’s use of a larger dredge bucket than anticipated.

“We provided the necessary information to our contractor when the project began, and instructed them to adhere to the conditions in the permit,” Port Chief Executive Tay Yoshitani said in a written statement. “We are very disappointed that the contractor violated the dredging permit.”

Bob Young: 206-464-2174 or byoung@seattletimes.com