BOSTON (AP) Massachusetts officials are trying to redefine the state’s coastline in a move that could give them more control over a proposed electricity-generating wind farm off the shore of Cape Cod.

State officials said Tuesday that a recently discovered pile of rocks in Nantucket Sound could change the state’s offshore border and expand state-controlled water by about 12 square miles. That would push back federal territorial water and could affect a developer’s bid to erect the nation’s first offshore wind power farm in the sound.

Gov. Mitt Romney, Sen. Edward Kennedy and others oppose the wind farm, which would consist of 130 turbines standing more than 420 feet high in Nantucket Sound. But they have little control over it, since it’s planned for federal water.

Opponents say the turbines would harm wildlife, destroy the offshore view and harm the fishing and boating industries.

Changing the state’s border to include the rocks appears to extend state water into as much as 10 percent of the proposed wind farm’s area, affecting 10 to 13 turbines, state officials said.

States are allowed to count as part of their area any naturally occurring offshore rocks that are exposed at median low tide. State water extends three miles from where officials draw the border.

The U.S. Minerals Management Service is expected to post a notice about the border change in the Federal Registry by the end of the month, said Jon Carlisle, a spokesman for the Executive Office of Transportation, which oversees state boundaries.

“From our review of the landmass, that’s the appropriate new border,” Carlisle said.

He would not say if Romney pushed for the new borders in order to curtail the wind project.

“Really, one thing has nothing to do with another,” he said.

Last July, Romney asked the Army Corps of Engineers to postpone its review of the proposed wind farm, arguing the newly discovered pile of rocks, which is about the size of an SUV, might require changing the state border. He suggested that might force the developer to redraw plans or seek new permits from state agencies.

An Army Corps official dismissed the request at the time as a thinly veiled attempt to stop the project.

Mark Rodgers, a spokesman for Cape Wind Associates, the project’s developer, said he had not seen the border change proposal, but doubted it would seriously affect the project.

The turbines would generate 420 megawatts of electricity at peak times. Supporters say it would supply nearly three-quarters of the power used on the cape and islands.

In a related development, the 1st U.S. Circuit Court of Appeals on Wednesday upheld a lower court’s finding that federal authorities properly granted a permit for an offshore test data tower erected by the project’s developers. Project opponents had appealed the ruling, arguing the Army Corps of Engineers lacked authority to grant the permit.

-Associated Press