Experts: Gas in Gulf blowout is less damagingJuly 25, 2013 by Janet Mcconnaughey in Earth / Environment
(AP)—A blown-out natural gas well blazing off Louisiana's coast poses fewer environmental dangers than past offshore accidents because it appears to primarily involve gas that disperses relatively easily, scientists said Wednesday.
"A gas well's not going to result in any kind of major pollution—perhaps not even significant pollution if it's burning," said Ted Bourgoyne, the former chair of Louisiana State University's petroleum engineering department. He now runs the consultancy Bourgoyne Enterprises Inc.
Federal inspectors saw no sheens near the well during flyovers Wednesday morning, which indicates the gas is burning off without releasing oil or other hydrocarbons—which are sometimes found in gas wells—into the water. While it's not clear if the well in Tuesday's blowout contained any crude oil, officials and scientists agree that the latest mishap shouldn't be nearly as damaging as the BP oil spill that famously sent crude oil oozing ashore in 2010.
The fire broke out late Tuesday hours after the blowout, authorities said. Forty-four workers were evacuated from a drilling rig at the site, and no injuries were reported.
University of Georgia marine scientist Samantha "Mandy" Joye also said the pollution and health dangers posed by a gas well are quite different than those posed at the well where the Deepwater Horizon rig blew up in 2010, killing 11 people and spewing millions of gallons (liters) of oil for weeks.
"The biggest danger from gas is that it is extremely flammable. At high concentration, gas exposure can cause health issues (vomiting, headaches, and worse) but such high levels are not likely to be reached in warm, shallow waters," Joye said in an email response to questions.
That's not to say there were no dangers. The Coast Guard maintained traffic restrictions within 500 meters of the site and the Federal Aviation Administration restricted aircraft up to 2,000 feet (610 meters) over the area.
Tuesday's blowout occurred at a drilling rig adjacent to a natural gas platform that wasn't producing gas at the time. The rig was completing a "sidetrack well," which drills into the same well hole under the platform. Industry experts say such wells are used to remedy an obstruction or other problem with the original bore, or to access a different part of the gas reserve.
Gas spewed throughout the day and ignited late Tuesday night. The cause of the blowout was under investigation being overseen by the federal Bureau of Safety and Environmental Enforcement.
Rig owner Hercules Offshore Inc. said the plan to stop the flow of gas may include drilling a relief well to divert the gas from the accident site, which could take weeks.
"We are singularly focused on coming up with an action plan that would regain control over the well," said James Noe, an executive with Hercules, which was operating the rig for Walters Oil & Gas, an exploration and production company.
Natural gas—mostly methane—is far more soluble than oil, meaning it more easily dissolves, dilutes and disperses than crude oil, said Donald Boesch, president of the University of Maryland's Center for Environmental Science and a member of the federal panel that investigated the BP oil spill. That means concentrations would be are far less lethal to the marine environment, he said.
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"Experts: Gas in Gulf blowout is less damaging" July 25, 2013 https://phys.org/news/2013-07-experts-gas-gulf-blowout.html