BP Plc’s effort to curb damage from the Gulf of Mexico oil spill is venturing into uncharted scientific territory as the company sprays more dispersant than has ever before been used in the U.S.
BP is using airplanes to spray the detergent-like chemicals on oil reaching the ocean surface from its Macondo well after the April 20 blast that destroyed the Deepwater Horizon rig and caused it to sink two days later. BP has also used dispersants almost a mile under the water close to the leak, a method not tried before.
“People are concerned about the dispersants, but it’s important to understand that what we are trying to do is deal with a pretty large situation,” Environmental Protection Agency Administrator Lisa Jackson said in an interview yesterday. The EPA is trying to assess whether applying the chemicals underwater makes “a bad situation better.”
The chemicals are an environmental tradeoff, James Jones, a deputy assistant administrator for chemical safety and pollution prevention in the EPA, told a Senate Environment and Public Works subcommittee in Washington yesterday. About 5,000 barrels of oil a day is gushing from the well, BP said May 5, threatening the coast of states from Louisiana to Florida.
The EPA and National Oceanographic and Atmospheric Administration will review results of London-based BP’s third test of sub-sea dispersant applications, completed yesterday, to determine whether the practice can continue.
Like Household Soap
The dispersant chemicals, described by their manufacturer, Nalco Holding Co., of Naperville, Illinois, as similar to household soaps and detergents, scrub the oil from the water, breaking the crude into small clumps that microbes will eventually be able to digest.
The dispersant chemical, Corexit, contains surfactants, the same type of chemicals that make soap work. The ingredients of Corexit include 2-butoxyethanol, according to a data sheet from the company. That’s a clear, colorless liquid that smells like ether, and can cause irritation of the nose and eyes, headaches, and vomiting, if inhaled in large volumes, according to the Centers for Disease Control.
The chemicals will cause environmental damage, said Senator Benjamin Cardin, a Maryland Democrat, speaking at the Senate subcommittee hearing. While using the dispersing agents may be less damaging than allowing the oil to go untreated, the public may not realize the tradeoff being made, he said.
“We have no choice,” Cardin said. “We’ve got to prevent the oil from coming to the surface and getting into the currents or getting onto the beaches and destroying wildlife.”
The Gulf of Mexico is one of the country’s largest fishing grounds. Louisiana provides almost one-third of the seafood in the lower 48 states, with values exceeding $2.85 billion a year, according to Governor Bobby Jindal.
Jindal, a Republican, said the state has told the EPA it is concerned about the impact of subsea dispersants on fisheries.
A trade organization representing shrimpers has said the agents could be harmful.
“The widespread use of dispersants on the surface of the water and deep in the Gulf of Mexico near the spill is an unprecedented and risky response that may be more damaging than the oil itself,” John Williams, executive director of the Southern Shrimp Alliance, said in a May 10 statement.
The open Gulf has fewer juvenile fish and shrimp vulnerable to oiling than do the coastal marshes, NOAA spill trajectory forecaster Charlie Henry said last week. Using dispersant in the open ocean also lowers the amount of oil that could foul whales, sea turtles, and sea birds, he said.
The EPA had previously approved dispersants for use on the surface, and the EPA and NOAA are reviewing their use underwater.
Teams responding to oil slicks have used dispersants in the past, including on Alaska’s Prince William Sound after the Exxon Valdez spill in 1989.
BP sprayed the most dispersant ever used on a single slick in the U.S. within a week of the Macondo leak beginning, Dagmar Schmidt Etkin, a Cortland, New York-based oil spill consultant who has worked for BP, said April 30. At the time, the company had applied about 98,000 gallons of the chemicals.
Since then, planes have dropped a further 274,000 gallons of dispersant, the Joint Information Center said yesterday.
“We’re basically shifting the oil when dispersants are being used to a short-term potential threat offshore, to protect against a long-term threat near shore that we think is much more important in the balance,” Henry at the NOAA said. “All we can do is minimize the impact to the environment.”