The Cape Wind project has cleared one more hurdle.
The Federal Aviation Administration on Monday ruled that the 130 offshore turbines planned for Nantucket Sound pose no threat to aircraft, provided they are properly installed, marked and lighted.
The study analyzed any effect the turbines might have on airplanes departing or arriving at all public airports, military airports of other aeronautical facilities in the region.
The FAA had given its OK to the wind farm twice before, saying as long as the turbines were properly lit, it would be safe for planes to fly around them. But the question remained whether the spinning blades would interfere with a radar station on the Cape.
In its latest ruling, the FAA says it will make technological upgrades to make sure the wind farm won’t disturb radar operations — upgrades for which Cape Wind's developer must pay. The ruling also spells out the lighting that needs to be installed while the wind turbines are going up.
Cape Wind spokesman Mark Rodgers said his organization is pleased with the decision and would "provide the FAA with the funds they need to modernize and enhance their radar facility at Otis Air Force Base."
Audra Parker, president and CEO of the Alliance to Protect Nantucket Sound, said her group would challenge the FAA ruling and request a review of the decision.
Parker's organization said in a statement, "(Monday's) FAA decision confirms that the proposed turbines would interfere with radar, but relies on unproven theoretical mitigation to resolve this serious safety issue."
Opponents have until June 16 to file a petition with the FAA asking for a review of the ruling.
The decision comes a month after Interior Secretary Ken Salazar gave his approval to the first-in-the-nation wind farm.
The Associated Press contributed to this report.
This program aired on May 17, 2010. The audio for this program is not available.