On Aug. 18 the Bureau of Ocean Energy Management (BOEM) issued a proposed sale notice for 742,947 acres of seafloor in the Massachusetts Wind Energy Area (WEA). In combination with the adjacent 164,000-acre Rhode Island/Massachusetts WEA, nearly a million acres of seafloor is slated to be occupied by wind-turbine towers. The final sales notice is expected later this month.
The Mass. WEA offshore wind farm is expected to feature up to 2,480 wind turbines and generate 5,000 megawatts of power – enough energy to power half of the homes in Massachusetts. At current lease prices of $3 a acre, the Mass. WEA could also generate up to $2.23 million per year in federal revenues.
BOEM will auction the Mass. WEA in four leases because of its size. Successful bidders will be allowed to perform site characterizations and site assessments on the lease areas over the next five years, but not erect turbines.
These site-planning activities have raised concerns among environmental organizations that support renewable energy but not at the risk of harm to marine life. Pile driving for up to 13 377-foot-tall meteorological towers and high-resolution geophysical seafloor surveys creates noise, resulting in the harassment of endangered species, notably the critically endangered North Atlantic right whale, that can lead to behavioral changes.
When BOEM released a revised environmental assessment for the Mass. WEA in June, it rejected an alternative that would have eliminated a right whale springtime feeding ground from the lease area, opting instead for standard operating conditions (SOCs). It also closed public comment and issued a finding of no significant impact.
SOCs require a single onboard observer to spot endangered whales, sea turtles and pinnipeds and order a work shutdown if they are spotted within an exclusion area. Vessel speeds are restricted to 10 knots in the WEA for vessels greater than 65 feet in length, and work at night or in low visibility is prohibited unless a mitigation plan is submitted to BOEM.
“SOCs were developed using industry standards,” BOEM marine biologist Brian Hooker said. A 60-minute standard is used because most whales must surface after an hour underwater, according to Hooker.
“What other people have done is to use higher-frequency equipment at night above the hearing range of endangered species and lower frequency during the day,” he said. Observers are still needed to avoid vessel strikes at night.
Environmentalists have argued that BOEM should implement more restrictive mitigative measures in the leases, which wouldn’t require additional environmental review.
Right whales are few
Fewer than 500 North Atlantic right whales are left on the planet, according to scientific estimates. The calving rate is one-third what it should be and is lower than the species’ mortality rate, according to the North Atlantic Right Whale Consortium (NARWC). Major threats to right whale survival are entanglement with fishing gear and vessel strikes.
The planning stage of the Mass. WEA is expected to generate between 2,800 and 6,500 vessel trips over five years. Up to 1,200 vessel trips could have been eliminated under an alternative that removed a strip of seafloor from the lease area – a location where right whales are known to congregate during spring migration. In fact, 98 male right whales were spotted in this area in June 2013, nearly a quarter of the entire remaining North Atlantic right whale population.
Scott Kraus, head of the NARWC and vice president for research at the New England Aquarium, said increased professional observers are needed beyond the single observer required in the SOCs. Even with professional research observers, efficacy in spotting drops substantially after two hours of scanning the ocean.
“One of the frustrations is that they’re putting the cart before the horse,” Kraus said. “Aerial surveys have not been completed in either area.”
New England Aquarium performs the aerial surveys, with funding from BOEM and the Massachusetts Clean Energy Center. The Mass. WEA is in its third and final year of aerial surveys, but won’t be completed until next spring.
After the nearby R.I./Mass. WEA was leased with similar SOCs, the Conservation Law Foundation (CLF), the Natural Resources Defense Council and the National Wildlife Federation collaborated with wind developer Deepwater Wind to take extra mitigative measures through a separate agreement endorsed by Environment America, Oceana, the Sierra Club and the International Fund for Animal Welfare.
That agreement calls for seasonal restrictions based on historical migration patterns of right whales, additional passive acoustic monitoring to detect the whales presence, using twice as many professional observers and adding a second vessel at the periphery of exclusion zones to better spot approaching marine life. Extensive use of noise attenuation and source-level reduction technology during pile driving also is required under the agreement.
“We would like to see those measures as conditions of the (Mass. WEA) lease,” said Priscilla Brooks of the CLF. “Our work focused on the North Atlantic right whale, which we saw as being one of the most endangered species on the planet.”
Brooks said advancing environmentally sustainable wind energy should include addressing right whale issues and reducing any risk. “Even the loss of one right whale has population-level effects,” she said.
CLF says more rigorous mitigative measures should be included in the leases, including a 1,620-foot extension zone for all marine mammals and sea turtles, and performing passive acoustic monitoring and aerial surveys during certain seasons when right whales are known to be in the area.
Oceana’s comments went even further. Noting that there are fewer than 150 breeding-age female right whales, it recommended that all night and low-visibility activities be prohibited to avoid vessel strikes or potential injury.
“Our recommendations focused on the right whale because the Mass. WEA is close to their critical habitat,” said Andrew Menaquale, Oceana’s energy analyst.
He noted that endangered sea turtles swim 2-3 feet below the surface and are more difficult to observe when they surface, may also be at risk.
“We don’t have time-series data in that area yet. But these agreements are probably based on the best available data at the moment,” Kraus said.
Kraus consulted on the R.I./Mass. agreement and signed off on a similar agreement for the mid-Atlantic wind-energy areas. He noted that such agreements allow for modification if new information shows different whale movement and behaviors. Once the full data set is available and analyzed, he said, it can be used to inform decisions.
He cautioned against using seasonal restrictions in all areas. The problem is that the ocean is changing, and so past data isn’t always predictive of the future, Kraus said.
Plenty of marine visitors
During the two-year environmental review for the Mass. WEA, studies found that noise generated by pile driving and high-resolution geophysical seafloor surveys will reach levels that would adversely impact a host of endangered marine mammals and sea turtles, in addition to the critically endangered right whale.
Endangered fin, sei, humpback and sperm whales, and Kemp’s ridley, green, leatherback and northwest Atlantic loggerhead turtles that frequent the Mass. WEA would also be impacted.
The seafloor surveys, also called geotechnical and geophysical surveys, include the use of “boomers” and “CHIRP”equipment operated within the hearing range of these species at levels that can cause duress under the Marine Mammal Protection Act (MMPA).
Based on the use of SOCs, the National Marine Fisheries Services, which is charged with enforcing the MMPA, issued a biological opinion in April 2013 that said although injuries will be caused to individual members, “the proposed action may adversely affect but is not likely to jeopardize the continued existence” of endangered species.
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