LEE, Maine — Opponents and proponents have begun two days of public hearings before the state’s top environmental agency arguing the merits and problems with an industrial wind site proposed for Bowers Mountain.

Project intervenors will have two full days of testimony and cross examination followed by night sessions for more public comment on Tuesday, April 30, and Wednesday, May 1, at Lee Academy.

The Maine Department of Environmental Protection is giving the public a full opportunity to contribute to the process by which First Wind of Massachusetts’ project will be approved or denied, a DEP spokeswoman has said. The public hearing is DEP’s first for a proposed wind project.

Officials from Champlain Wind LLC, a First Wind subsidiary, seek to build a 48-megawatt wind site atop Bowers, which is located in Carroll Plantation in eastern Penobscot County. It is the firm’s second application seeking to build there.

The first proposal was denied by the now-defunct Land Use Regulation Commission in April 2012 in the first significant victory against a wind developer by a Maine anti-wind group since they started fighting projects almost seven years ago.

Opposing intervenors will include registered Maine Master Guide David Corrigan and representatives of the Partnership for the Preservation of the Downeast Lakes Watershed. The Conservation Law Foundation and the Maine Renewable Energy Associates are among the supporting intervenors.

The American Lung Association, Conservation Law Foundation, Environment Maine, Maine Audubon Society and Sierra Club Maine announced their support Thursday for the 16-turbine project.

The announcement marks the first time so many such groups have supported a wind project in Maine, said Glen Brand of Sierra Club Maine.

Intervenor status allows those who receive the designation to be a formal party to the process, providing an opportunity for participation beyond what is typically afforded to the public, including the opportunity to present evidence under oath and cross-examine other parties.

Absent a lunch hour and some 15-minute breaks, the intervenors will present their cases about the project from 9 a.m. to 5 p.m. on both days. Public hearings for other interested parties will start at 6 p.m. on both days. The night hearings are open-ended in an effort to hear from all speakers.