Concerned environmental groups say this week's U.S. House vote to authorize the funding of the Savannah Harbor Expansion project isn't the last word on the issue.

The project has significant support. The House vote on Wednesday was overwhelming. Every Georgia Congressman supported it.

A major environmental lawsuit seeking to block the project was also settled this year.

Still, some opponents say stumbling blocks could halt the nearly $700 million dollar port expansion.

Steve Willis of the Sierra Club says the settlement requires oxygen injectors, or bubblers, be tested in the harbor before much of work begins.

"They cannot dredge inland until they can prove that those bubblers work," Willis says. "And there's no guarantee that's going to happen."

Three federal environmental agencies have approved the injectors to mitigate environmental concerns.

However, Willis says another potential roadblock is litigation.

"It is possible that there could be additional legal action," Willis says. "The agreement not to pursue further legal action only applied to the specific organizations involved in the suit in South Carolina."

Earlier this year, several environmental groups settled a lawsuit that sought to block the project in a South Carolina federal court.

Tags: sierra club, Georgia Ports Authority, GPBnews, orlando montoya, Steve Willis, Harbor deepening lawsuit