The Army Corps of Engineers has decided to allow dredging to deepen the shipping channel of the Delaware River despite objections from Delaware state officials, clearing the way for a project long sought to benefit ports in the Philadelphia region.

Jo-Ellen Darcy, assistant Army secretary for civil works, decided Friday to continue to rely on her predecessor's determination that a permit from Delaware was not needed to proceed, according to officials familiar with the issue.

"It's a giant matter of jobs," said Sen. Arlen Specter (D., Pa.), who took the lead in pushing for the decision with Gov. Rendell and Sen. Bob Casey (D., Pa.). "I think the merits are pretty plain, and there are no environmental downsides."

The spoil from the project will be deposited in abandoned coal mines in northeastern Pennsylvania under the current plan, officials have said.

New Jersey had fought the project for years because plans called for millions of tons of sand and muck to be dumped there, but Gov. Corzine dropped the state's opposition in 2007 when Pennsylvania agreed to take the material.

Darcy's determination would sweep aside Delaware's July denial of an environmental permit for the $379 million project. Environmentalists and Delaware officials are concerned that the dredging could stir up long-settled contaminants that would harm drinking water and aquatic life.

The permit was denied, Delaware environmental officials said, because the project had grown since the federal government originally applied for it in 2001.

Dan Fee, spokesman for the Philadelphia Regional Port Authority, said the work may begin by the end of the year as an extension of the contract for annual maintenance dredging.

Pennsylvania has committed $30 million for the initial part of the project. The work will proceed with state and already-appropriated federal money.

The Delaware River's current depth of 40 feet does not accommodate most modern ships and puts Philadelphia's port at a competitive disadvantage, since depths at other Eastern ports, including New York and Baltimore, approach 50 feet. The project would deepen the shipping channel to 45 feet.

"We are gratified at the result," Rendell said last night in an interview. "This is a great thing for our port. I believe that 10 years from now there will be 10,000 to 20,000 new jobs at the port for longshoremen, Teamsters, and the like."

The Corps is relying on an April policy memo from Darcy's predecessor, John Paul Woodley, that "federal supremacy" in order to protect interstate navigation trumped Delaware's rights to block it.

Delaware Gov. Jack Markell said in a statement that the Corps' push to go forward without the permit "raises significant concerns," the Associated Press reported.

The section of river that is in Delaware is the first area to be targeted for deepening and is considered crucial for the overall project.

"Pennsylvania intends to be a good neighbor," said Rendell, adding that the project will be subject to "joint oversight with Delaware and New Jersey in order to allay any environmental concerns."

Darcy said the Corps would seek a permit from Delaware even though it is not required.

The ports of Wilmington and South Jersey also will benefit from the dredging, Rendell said. "This is not a matter of one state triumphing over another," he said.

Contact staff writer Thomas Fitzgerald at 215-854-2718 or tfitzgerald@phillynews.com.