Seismic surveys debated at offshore energy meeting

Underwater sound waves that map oil and gas deposits, but may hurt marine mammals and fish, were debated Wednesday at a meeting on developing offshore energy.

North Carolina is reviewing two proposals for seismic surveying, as the technique is called, that would be conducted in federal waters this year. The state expects to decide by late April whether the plans are consistent with its coastal management policies.

The surveys came up during an invitation-only meeting in Raleigh hosted by the Department of Environment and Natural Resources.

Discussion of seismic surveys follows last week’s administration tentative proposal to sell leases for oil and gas drilling in federal waters off the coast of the Carolinas, Virginia and Georgia.

The Bureau of Ocean Energy Management will hold a public meeting on the proposal Feb. 17 in Wilmington. Public comment on the announcement ends March 30.

Nine companies have applied for permission to conduct seismic surveys off those states, with North Carolina a focal point for those studies.

The technique uses arrays of airguns to produce powerful sound waves that penetrate the ocean floor and pinpoint oil and gas deposits. But it’s also loud.

The blasts can cause hearing loss, disrupt feeding and mating of marine mammals such as whales and porpoises, and can make fishing catches drop by up to 70 percent, said speaker Claire Douglass of the advocacy group Oceana.

“It’s not only large and loud, it’s going to happen over and over again,” she said, referring to the number of companies interested in surveying the Atlantic.

Ken Wells of the International Association of Geophysical Contractors defended the practice. He quoted the federal Bureau of Ocean Energy Management as saying no scientific evidence of harm to ocean life has been documented.

Wells said seismic surveys have been done for 40 years in the Gulf of Mexico. “We’re a quiet industry that does no real damage to the area,” he said.

The National Marine Fisheries Service has concluded that the Atlantic surveys would temporarily disrupt marine mammals, including endangered whales, but would not jeopardize their survival. A second environmental analysis said the surveys would have “moderate” impacts on the animals.

Offshore wind energy was also on Wednesday’s agenda. The Obama administration this month released an environmental study that supports potential leases of 300,000 acres off the North Carolina coast for wind farms.

States in the Southeast have most of the Atlantic’s wind-energy potential that is in shallow water and at least 12 miles offshore, said Brian O’Hara of the Southeastern Wind Coalition, which advocates for the industry. Shallow water makes wind turbines easier to build, while a 12-mile distance would keep them mostly out of sight from shore.

Low construction costs and the presence of companies that make parts for the wind industry further position the Southeast for wind development, O’Hara said.

This story was originally published February 4, 2015 at 6:00 AM with the headline "Seismic surveys debated at offshore energy meeting."