The Trump administration is pressing ahead with processing permits that would allow companies to search for oil and gas deposits using potentially harmful seismic blasts in the Atlantic Ocean, despite its decision to delay an unprecedented plan to sell federal leases on nearly the entire U.S. outer continental shelf.

Seven geology companies are vying for permits at the Bureau of Ocean Energy Management, a division of the Interior Department, to map the ocean floor from New Jersey to Florida using seismic sound waves that, according to some scientists, harm fish and marine mammals, including the endangered North Atlantic right whale that relies on echo location to find food and mates and to keep in touch with its rare offspring.

Bureau officials confirmed this week that permits are being considered regardless of Interior Secretary David Bernhardt’s decision to shelve its five-year leasing plan in federal waters on the outer continental shelf. The decision followed a ruling in March by U.S. District Judge Sharon Gleason that President Trump’s revocation of an Obama administration ban on oil and gas industry drilling in the Arctic and Atlantic oceans is illegal. Only Congress can undo the ban, the judge said.

Seismic mapping is also being challenged in court by conservation groups and state attorneys general along the Eastern Seaboard. A federal judge in South Carolina is considering an injunction request against any work moving forward until the case is decided. Oil and gas leases and seismic mapping are also opposed by Democratic and Republican governors along the coast, along with congressional and state lawmakers.

Five of the companies would use seismic technology that required an additional “incidental take” permit from the National Oceanic and Atmospheric Administration, allowing them to harass and possibly harm mammals in the course of their work. Those companies — Spectrum Geo, Ion Geophysical, CGG Services, WesternGeco and TGS-NOPEC Geophysical Company, all with offices in Houston — were granted NOAA permits in November.

Two additional companies, TDI Brooks International and ABI Holdings Limited, submitted applications to use seismic equipment that requires a permit from only the bureau, an official said. An eighth company, PGS, has a pending application that has not been reviewed, the official said, because it does not have the NOAA permit.

Geology companies put ships to sea trailing long rods just under the surface. The rods emit piercing underwater sounds that map the ocean floor as the sounds bounce off it. Often, oil and gas companies enter into contracts worth millions of dollars for the seismic data geology that companies collect. The companies also invest in seismic mapping to sell data showing the likely location of oil and gas deposits to energy companies.

The acrimony over NOAA’s issuance of the permits resulted in a tense hearing in the House, where a congressman blasted an agency official with an air horn.

Rep. Joe Cunningham (D-S.C.) faced off with Chris Oliver, a NOAA administrator for fisheries who defended issuing permits that would excuse companies if they happened to harass dolphins, whales and harm fish stocks that they rely on for food.

“It’s fair to say seismic air gun blasting is extremely loud and disruptive ... is that correct?” the congressman asked.

“I don’t know exactly how loud it is: I actually never experienced it myself,” Oliver replied.

Cunningham lifted a 120-decibel horn and blasted it at Oliver, filling the small committee room with an eardrum-splitting noise.

“Was that disruptive?” Cunningham asked.

“It was irritating, but I didn’t find it too disruptive,” Oliver said.

But seismic mapping does not happen with a single blast of a horn. It continues every 10 seconds for hours, days, weeks and possibly months.

“There is absolutely no rational reason for the Interior Department to continue processing seismic testing permits after they’ve announced they will not be expanding offshore oil and gas drilling,” Cunningham said in a statement Tuesday. “Needlessly inflicting damage to our marine economy and wildlife through dangerous and unwanted. … air gun blasting is unacceptable.”

Cunningham vowed to continue fighting it. But an industry representative defended the practice for the valuable data it provides.

“When you have to make an important decision, it’s critical to have important information,” said Gail Adams, vice president of communications for the International Association of Geophysical Contractors. “If the decision is going to be to delay the five-year plan, then BOEM wants to go ahead with the permits so they can be informed.”

Adams said that “there will always be value in the data our members provide” and that “it behooves us as a nation to understand our resources for future planning.”

Opponents say those resources include marine life, sport fishing and clean beaches that have drawn vacationers to Atlantic states for nearly a century. They bring millions of dollars in revenue and taxes that support hotels, shops and hundreds of thousands of workers. Officials from Massachusetts to Florida worry that seismic mapping will lead to oil and gas leasing, drilling and spills that will hurt tourism.

The gulf between Mississippi and Texas is a rich and productive oil and gas region that yielded more than 600 million barrels last year, about 20 percent of the total U.S. oil production. But 330,000 gallons of crude are spilled each year from offshore platforms and onshore oil tanks just in Louisiana, according to a state agency that monitors them.