JACKSONVILLE, Fla. - The St. Johns Riverkeeper argues that more studies need to be done before allowing the Jacksonville Port Authority to expand dredging efforts another 11 miles down the channel.

Phase one is expected to start the middle of next month, but the St. Johns Riverkeeper has filed a motion to temporarily stop the process.

The Riverkeeper argues people need to know more answers before this dredging takes place.

Lisa Rinaman argues not only are the studies important for the environment, but she believes that’s what is required by federal law.

“This injunction is actually addressing new developments that actual create more risk, more unknowns and more unanswered questions," Rinaman said.

Rinaman says there could be economic and environmental benefit from the Jacksonville Port Authority agreeing to scale back original dredging efforts from 13 to 11 miles, she says there’s only one problem.

“There’s no benefit cost ratio, there’s no justification for federal spending of an 11 mile project," she said.

It is estimated that the project has a price tag of $500 million. In addition to her concern of a potential lack of return on investment, Rinaman is concerned that deeper dredging needs deeper review by the U.S. Army Corps of Engineers before funding should be released.

“They’re looking at the flooding impact, but they’re doing it concurrent with the dredging, we think it has to be done first, citizens deserve to understand what the risks are, what the impacts are," Rinaman said.

Her biggest concern is flooding with an additional seven feet of dredging. The Army Corp predicted a potential additional foot of storm surge. The Army Corp did agree last month to re-evaluate the latest impacts from Hurricane Irma and Nor’easters, but Rinaman feels that too was incomplete.

“It doesn’t look at rainfall, it doesn’t look at other inflows from the tributaries and to have a true flood analysis you need to look at the big picture and the Corp failed to do so," Rinaman said.

Meanwhile, the Jacksonville Port Authority says the deepening project represents the single largest opportunity for Jacksonville to grow and after a decade of study, public input and full regulatory approval, the time has come to start this project.

The St. Johns Riverkeeper is set for a January hearing to discuss why they believe this dredging needs to be review again.