In an effort to decrease the number of migratory birds killed each year by wind turbines in the Altamont Pass, the attorney general's office Tuesday announced an agreement between environmental groups and one of the area's major wind energy producers to upgrade its facilities with safer, more efficient turbines.
Attorney General Jerry Brown's office said that NextEra Energy Resources -- the largest turbine operator in the Altamont Pass Wind Resources Area, which spans Alameda and Contra Costa counties -- has agreed to replace 2,400 wind turbines over the next four years and replace all its existing turbines no later than 2015.
"NextEra is the only company we're settling with, but the company owns about 50 percent of the turbines at the site," attorney general spokeswoman Christine Gasparac said.
Californians for Renewable Energy and five Bay Area Audubon Society chapters were involved in today's settlement.
"Our agreement sets an aggressive schedule for removing the old-generation turbines and replacing them with new-generation turbines that should substantially reduce impacts to birds," Golden Gate Audubon Society conservation director Mike Lynes said in a statement.
The more than 5,000 wind turbines in Altamont Pass were found to kill more than 4,000 birds annually, including federally protected species such as the golden eagle, according to a 2004 study commissioned by the California Energy Commission.
According to the attorney general's office, the bird fatalities in the Altamont Pass are higher than any other wind farm in the country, due to its position on a major migratory bird route.
The new turbines, which will replace those installed in the 1980s, are expected to be more efficient energy producers as well as safer for birds.
"Any time birds are continuing to be killed out there, we can't call it a victory," Golden Gate Audubon executive director Mark Welther said. "But this is a significant step forward."
Environmental experts are hoping the new infrastructure will reduce the number of birds killed each year by up to 80 percent.
NextEra has agreed to put up new turbines in locations believed to be more environmentally friendly.
The renewable energy company has also agreed to pay $2.5 million in mitigation fees -- half to the East Bay and Livermore area park districts for raptor habitat creation and half to the state Energy Commission's Public Integrated Research Program.