ORLANDO, Fla. -- A private rail company now has the greenlight to expand in Orange County, building a track in a wetland area.

Orange County Commission to discuss Brightline

Private rail company wants a Conservation Area Impact Permit

All Aboard Florida needs to build 40 new miles of track

Orange County commissioners Tuesday approved All Aboard Florida's request for a Conservation Area Impact Permit to allow construction to move forward.

All Aboard Florida is looking to expand its Brightline passenger rail service from Miami to Orlando International Airport.

The private company needs to build 40 miles of new track. But there are environmental concerns about the project, including its impact to wetlands in Orange County.

Phase two would have the company's Brightline trains travel parallel to State Road 528 east, turn south near Cocoa, and then connect to train stations in West Palm Beach, Fort Lauderdale and Miami.

All Aboard Florida plans to use Orlando International Airport's new Intermodal Terminal Facility as its Orlando train station.

Construction of new rail will impact more than 200 acres of wetlands and surface waters, including the St. Johns and Econ Rivers.

"There will be wetlands that are used in the project, but they're being mitigated," said Michael Cegelis, Brightline's vice president of engineering.

The private passenger rail project has been under constant attack from critics concerned about safety, noise, the use of federal funds and environmental impacts.

Martin and Indian River counties are suing All Aboard Florida in federal court, trying to block the expansion.

Brightline plans to serve the Orlando area by 2021.

Reporter Jerry Hume contributed to this report.