Maryland's first industrial-scale wind energy project would be required under a federal plan issued Monday to slow down its turbines at certain times of the year to reduce the number of endangered bats that might be killed by the long, spinning blades.
Exelon Power, which owns and operates the 28-turbine Criterion wind project in Garrett County, also would have to protect one or more bat caves in other states to make up for any federally protected Indiana bats its turbines might harm.
The tiny, insect-eating Indiana bats, which are found across the eastern United States, have been officially listed since 1967 as in danger of disappearing. Biologists say their number has become even more depleted in the past half-century as a result of human disturbance of their caves, pesticide poisoning and a recent disease, white-nose syndrome.
The draft "habitat conservation plan," prepared for the U.S. Fish and Wildlife Service, marks the first time the federal agency has sought to place conditions on the operation of a commercial wind project in the Northeast to protect rare bats and birds from harm by the towering structures. Restrictions have been placed on a pair of projects in Hawaii and are proposed on a 100-turbine project in Ohio to protect Indiana bats there.
As part of the plan, federal officials are weighing whether to issue Exelon an "incidental take" permit authorizing the loss of a small number of Indiana bats to its turbines atop Maryland's tallest peak, Backbone Mountain. Such a permit is needed under the Endangered Species Act, which makes it illegal to kill or harm any animal under its protection. A decision is expected once a public comment period ends Sept. 28.
The Criterion project, which began operating in December 2010, is projected to kill perhaps 28 of the extremely rare bats over its 20-year lifespan, which the plan says would not make a significant dent in the overall population.
But Exelon could reduce the number killed to 14 by "feathering" its turbine blades whenever gentle winds are blowing from July 15 until Oct. 15, the plan suggests. That's when the bats are most likely to be migrating through the area and in the air pursuing insects, according to Cherry Keller, an endangered species biologist with the wildlife service's Chesapeake Bay office in Annapolis. Slowing the turbines reduces air turbulence, which can injure or kill the animals even if they do not get hit by the blades.
Julie Slacum, a supervisor in the wildlife service's bay office, said the energy company would be required to mitigate or make up for the loss of that many bats by protecting one or more caves where they are known to hibernate, or by installing a grate over a cave or mine opening to keep people and other large animals out while letting bats fly through.
She said conditions were dictated by the relatively small scale of Criterion's project, with just 28 turbines, and the belief it is not located near any known breeding or hibernation caves for Indiana bats. None of the bats was seen during pre-construction surveys, though remote listening devices did pick up the bats' signature vocalizations. Biologists believe that some may fly through the area as they migrate, Slacum said.
Exelon spokesman Kevin Thornton would not say how much slowing the turbine blades would cost the energy company, though he noted that the change in operations has already begun. Thornton did say Exelon has pledged to spend $170,000 over the next couple years to protect bat habitat from disturbance, and would commit more if need be. The plan has identified several likely sites in neighboring states.
"We're trying to do the right thing," Thornton said, adding, "It takes time."
The $140 million wind project, while supported by mainstream environmental groups eager to promote cleaner alternatives to burning climate-altering coal, has drawn fire from some conservationists concerned about the potential harm to bats and birds. A pair of conservation groups threatened to sue Constellation Energy, which built the wind project before being acquired by Chicago-based Exelon, as it began construction two years ago. The company did not approach federal wildlife officials to discuss bat protections until the work was already under way.
Save Western Maryland, one of the groups that had threatened legal action, emailed a statement Monday objecting to the wildlife service's proposal, saying any Indiana bats harmed are too many.
Group member Eric Robison said the project's developers violated state and federal environmental laws during construction "and now want our community to look the other way as they continue to do harm." In addition to the group's contention that the project harmed endangered species, the developer was fined at one point by state officials for failing to control erosion from the building site.