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Critics Doubt Liquefied Natural Gas Safety
58 minutes ago Science - AP
By H. JOSEF HEBERT, Associated Press Writer
WASHINGTON - When an explosion flattened a liquefied natural gas plant in Algeria, killing 30 workers, one might say the heat was felt half a world away — in coastal towns in New England, Alabama and California. The Algerian inferno a year ago undermined industry arguments that the modern era of LNG transport is inherently safe. It also became rallying point for groups fighting proposed new LNG terminals in their towns.
Companies are beginning to gear up for LNG imports. As many as a dozen new terminals are expected over the next decade. To many energy experts, fear of a devastating LNG fire from an accident or terrorist attack is the toughest obstacle facing the industry.
A recent government report, the most comprehensive examination of LNG tanker risks to date, concluded that terrorists have the capability to tear a huge hole into a tanker. That would unleash a spill and intense fire that would cause major injuries and burn buildings as far as one-third of a mile away. People a mile away could suffer second degree burns, the report said.
LNG imports are widely acknowledged to be crucial in meeting future natural gas needs. Yet public concern about safety has led more than a half-dozen communities to reject an LNG import terminal or rally against a proposed facility.
Critics want double-hulled tankers carrying more than 30 million gallons of LNG barred from traversing waterways in populated areas or within a mile of homes, schools and office buildings.
Industry advocates say the safety risks are exaggerated, citing a 40-year history of more than 35,000 shipments of LNG worldwide without a significant release of the fuel or a fire.
They also argue that the Algerian accident, involving a liquid gas leak and explosion set off by a spark from a boiler, could not happen at U.S. facilities because of different equipment and design.
The recent federal study by Sandia National Laboratory found potentially harrowing consequences from spills. The report also said the chance of an intentional spill could be reduced greatly with "a halo of security" for arriving tankers.
"We can significantly reduce the likelihood of a terrorist attack occurring with security planning and mitigation," says Mark Maddox, a deputy assistant secretary for fossil fuels at the Energy Department, which commissioned the Sandia study.
Richard Sharples, executive director of the Center for Liquefied Natural Gas, an industry trade group, does not dispute the Sandia report's assessment of a "worst case" LNG accident.
But, he says, the "remarkable safety record" and close government scrutiny of LNG shipments make such an accident a "low probability."
The Sandia study, in fact, concludes the risks of an accidental release of LNG from a tanker are small. But it is post-Sept. 11 fears about terrorism that bring a new dimension to the debate over LNG transport.
For nearly half a century, the emphasis has been on preventing human error, not intentional acts.
Since the terrorist attacks, the Coast Guard has imposed tighter security on LNG tankers. Measures include four days notice of a tanker's arrival, information on its last ports of call and crew, and special sweeps and vessel boardings.
Rear Adm. Thomas Gilmour, the Coast Guard's assistant commandant for marine safety and security, said the Sandia findings will help "in further refining our risk reduction efforts." The study's classified version includes specific attack scenarios and their likely impact.
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As a frosty liquid, kept at minus-260 degrees Fahrenheit, LNG cannot explode or catch fire. Various studies agree that if a tanker is breached by a bomb or missile, the liquid flowing from its icy storage instantaneously would become a gas and ignite. The result: an extremely hot fire, as wide as three football fields.
The Sandia study concluded that a terrorist attack could blast a large enough hole — and possibly several holes — that would cause cascading damage. The cold liquid and intense heat of the fire would weaken adjacent tanks, causing them to fail and adding to the size of the spill and the blaze atop the water.
"The fire from such a spill would be very large ... perhaps up to a half-mile in diameter, or larger if more of the containment system failed," says Jerry Havens, a professor of chemical engineering at the University of Arkansas.
"We have no experience with fires this large, but we do know they could not be extinguished. They would have to burn themselves out," says Havens, who over three decades has studied the likely impact of LNG fires.
The industry's good safety record has actually made it harder to determine how much damage a large spill might cause. The only tests have been on spills of 10,000 gallons of LNG, not the 3 million gallons or more that scientists believe would be released if a tanker were breached by a bomb or missile.
Computer models about a major LNG vessel spill have produced widely different results.
One study assumed only a 3-foot hole and that waves would limit the spread of the fire. A second study assumed a breach of more than 30 feet across, resulting in a rapid spill and much bigger fire.
These models are uncertain because they rely on assumptions "about which fair-minded analysts may legitimately disagree," the Congressional Research Service said.
The Sandia study was ordered with the hope of resolving some of that disagreement.
It found "that the worst that can happen or near worst ... is really more than the industry has admitted so far," says James Fay, a semiretired professor at the Massachusetts Institute of Technology (news - web sites).
Since 1970, Fay has argued the government and industry were understating the potential dangers of a major fire.
In an interview, he said the Sandia study documented "that the worst that can happen is very bad." He scoffed at the suggestion that the impact of an LNG spill and fire could be mitigated.
"The fire is over in five minutes," he said. "You can't sound fire alarms and tell people to shuttle away from the harmful effects."
Rep. Ed Markey, D-Mass., who has pressed the Bush administration for tighter restrictions on siting LNG terminals, said the Sandia report has "destroyed any argument that LNG facilities should be based in urban areas."
A 1979 law says LNG regulators should "encourage" remote siting of import terminals.
Markey, however, says regulators have ignored Congress' intent and continued to consider sites in densely populated areas, especially in the Northeast where LNG facilities are being proposed in Providence, R.I., and in Fall River, Mass., and where tankers would travel through the heart of the community.
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Mark Robinson, a senior official at the Federal Energy Regulatory Commission (news - web sites) who is involved in LNG terminal siting, says he has no illusion about the prospects of an LNG-fed inferno spreading over water.
"It's a fire that can't happen," he said from his office near the Capitol. He meant that it cannot be allowed to happen. But he also insists that federal security requirements are sufficient to prevent terrorists from causing a spill.
"If I had to worry about my safety, or my family's safety, I'm a lot more worried working this close to the Capitol building than I would be living close to an LNG facility," he says.
Energy regulators have a dozen LNG terminal site proposals under consideration. They have approved expanding the four existing terminals and have given a green light to three new ones on the Gulf Coast.
Regulators must ensure the risk "is as close to zero as possible" while recognizing the need for reliable and affordable supplies of LNG, said the commission's chairman, Pat Wood, in an interview.
But he added that he and fellow commissioners "also recognize there is an economic need here if you want to have reliable and affordable supplies" of natural gas.
A native of Port Arthur, Texas, Wood says three LNG import sites "are going in my hometown potentially" and that has gives him a strong incentive to make sure the public is not in danger.
But in Fall River, Mass., Mayor Edward Lambert is not convinced that the government is committed to protecting the 5,000 people who live or work within a mile of a proposed LNG terminal in his town.
FERC officials acknowledged in a report that a tanker would have to maneuver up the Taunton River, which cuts through the heart of Fall River, and under four bridges, including one carrying an interstate highway. But the report also said risks from a possible terrorist attack on a tanker "can be managed." The commission has yet to rule on the project.
"It's downright foolish," Lambert said in a telephone interview. They want the town to bear "a risk no American citizen should be asked to bear when there are alternatives."
