AUGUSTA, Maine — The Maine Board of Environmental Protection voted Wednesday to uphold state regulators’ decision to grant a permit for a 50-turbine wind farm in Oakfield that would be the largest single wind energy project built in Maine to date.

By unanimous vote, the BEP rejected opponents’ requests to essentially rescind the permit issued in January by the Department of Environmental Protection and instead hold public hearings on several issues.

The developer, First Wind, has said the $360 million project could generate as many as 400 jobs during construction. Company officials said Wednesday it was too early to say when work on the project could begin.

“We are looking to move forward as soon as we can,” said Matt Kearns, First Wind’s vice president for development in the Northeast.

The group Protect Our Lakes and Island Falls resident Donna Davidge had appealed the permit, arguing the department failed to consider all evidence on potential impacts to wildlife, including bald eagles, and on the area’s scenic character. They also questioned whether First Wind had demonstrated the necessary financial capacity to complete the project.

Samantha DePoy-Warren, spokeswoman for the Department of Environmental Protection, wrote in an email that the unanimous vote affirms the staff’s six-month review of the project and “is yet another confirmation of the quality of our process.”

The board’s backing of the department means opponents will have to take their concerns to the courts if they choose to continue fighting the project.

Attorney Lynne Williams, who represented the appellants, said she will discuss the issue with her clients but that she is inclined to take the appeal to the state supreme court. Williams said she also was encouraged by board members’ substantive questions and the discussion about the lack of guidance on visual impacts from projects under the state’s expedited permitting process.

“I think we take baby steps forward with every appeal,” Williams said.

Located in the Aroostook County town of Oakfield, the project would feature 50 turbines — each standing more than 400 feet tall from base to blade tip — capable of generating up to 3 megawatts of power each. The project enjoys strong support from local residents who voted overwhelmingly to endorse agreements with First Wind that will produce $26.7 million in tax revenues and community benefits for the town over 20 years.

Kearns said the Oakfield project is unprecedented in Maine among wind energy facilities in terms of the scope of the benefit package to the local community and the potential for job creation.

“The great thing about where we are with the wind business in Maine is that Maine businesses know how to do this work,” Kearns said.

First Wind initially had intended to erect 34 smaller turbines in the Oakfield area but later sought regulatory approval for the larger configuration, which would locate turbines along the ridge lines of Sam Drew Mountain and Oakfield Hills.

But opponents suggested that the massive turbines would spoil views from Pleasant and Mattawamkeag lakes, which are important to the local tourism economy. They also suggested the turbines could harm bats and eagles.

Williams said that while she was disappointed with the outcome of Wednesday’s meeting, she was heartened by the discussion of visual impacts from wind projects. Members of the Land Use Regulation Commission have expressed frustration about the lack of standards or guidance for considering visual impacts under the expedited permitting system.

“I think there is a sense that the BEP is finally getting to the point where LURC has been for some time,” Williams said.