Amid the massive cargo-bearing ships at one of the world’s busiest seaports, a Mitsubishi subsidiary wants to build California’s first terminal for importing liquefied natural gas from overseas.

It claims the $400 million facility could meet 10 percent of California’s natural gas needs and help avert another energy crisis.

Opponents say terrorists or earthquakes could turn the terminal’s vast stores of super-cooled gas into a mile-high fireball, destroying the port and scorching people and buildings a mile away in downtown Long Beach.

“If you are close when that happens and you are out in the open, you are doomed,” said James Fay, a Massachusetts Institute of Technology professor emeritus and liquefied natural gas specialist. “No one is going to (be able to) come in and rescue those people.”

The liquefied gas industry claims an outstanding safety record, tight security, strong structures, multiple government reviews and other safeguards.

“We don’t believe any accident will leave our property,” said Thomas Giles, chief executive officer for Sound Energy Solutions, the Mitsubishi subsidiary proposing the Long Beach terminal.

But the possibility of monumental fires and increased reliance on foreign fuels is generating growing opposition to recent proposals to put an LNG terminal at Long Beach and three more off Southern California’s coast.

Protests in Eureka and Vallejo already killed terminal proposals in those communities. Malibu’s City Council voted to oppose two proposed terminals off its shores.

The California Sierra Club is fighting all the proposals and has joined 26 other environmental groups in urging the state to pursue energy efficiency instead of new energy production.

The environmental coalition plans to voice its concerns in a meeting today with state Resources Secretary Mike Chrisman and Environmental Secretary Terry Tamminen.

Chrisman said at least one terminal should be built in the state, if it can operate safely without harming the environment.

He plans a 10-day trip to Australia and South Korea later this month to tour LNG facilities.

Gov. Arnold Schwarzenegger met with Australia’s prime minister about Australian firm BHP Billiton’s proposal to build an import terminal 14 miles from southern Ventura County’s beaches.

The governor has the power to veto offshore terminals but not the onshore one at Long Beach, a city of more than 460,000 people.

Ashley Snee, the governor’s spokeswoman, said the offshore terminal is “one of the possibilities” Schwarzenegger is examining to avoid an energy crisis.

Rep. Doug Ose, R-Sacramento, is the chairman of a House of Representatives subcommittee examining the issue, and he said LNG is the best hope for substantially increasing the natural gas supply, thereby reducing gas prices.

“We have a choice between paying $6 to $8 per cubic foot for natural gas, or we have the opportunity to drive the price down to $3,” he said. “A $2 difference in price equates to $2 billion in additional costs for our homes and factories.”

The higher gas prices have made the fuel competitive with domestic sources for the first time in 30 years, and energy firms have proposed more than 30 terminals in the United States.

Seven would be on the West Coast, where there are no facilities for receiving the fuel.

The fuel is natural gas turned into a highly concentrated liquid by cooling it to minus 260 degrees Fahrenheit.

Ships can carry vast quantities of gas in its liquid form and deliver it to the United States at one of four East Coast terminals.

There, heat restores it to its natural gaseous state, and it’s delivered via pipeline to customers.

LNG is not flammable so long as it is liquid. But it can ignite when mixed with oxygen in concentrations of 5 percent to 15 percent.

In an uncontrolled release, the Congressional Research Service said, a pool fire could erupt that would burn hotter and faster than a gasoline or oil fire. It said the fire could be extinguished only after all the fuel was consumed.

Experts say LNG fires generate so much heat that people a half-mile from the flames could suffer severe burns. As a result, some experts have urged construction of offshore facilities.

The Congressional Research Service said LNG released over water could create a “flameless explosion.” Local residents opposed to terminals off the California coast claimed clouds of flammable gas could float onshore.

Steve Meehan, project manager for the BHP Billiton terminal, said the “largest area of potential hazard is three to four miles.” The BHP terminal would be located 14 miles from shore.

Questions about the fuel’s safety date back to 1944, when a Cleveland, Ohio, tank built with inferior steel ruptured and spilled LNG into the street and storm-sewer system. The gas ignited, triggering an explosion and fire that killed 128 people.

The industry uses better steel today and has reported no further tank ruptures in the United States.

It also argues its ships have made more than 33,000 trips in the past 45 years and experienced no major fires or explosions.

In January, though, an explosion and fire at an Algerian LNG production plant killed 27 people. California and federal officials said the boiler that triggered the Algerian explosion wouldn’t be used in U.S. import terminals.

But the Sept. 11, 2001, terrorist attacks heightened fears of LNG terminals and ships being used as weapons by America’s enemies.

The federal government shut down LNG shipments through Boston’s harbor for almost a month after Sept. 11 to ensure public safety.

Opponents warn that a ship could be commandeered due to lax security. The Department of Homeland Security recently acknowledged that al-Qaida operatives linked to the failed 2000 millennium bomb plot at Los Angeles International Airport sneaked into the United States aboard Algerian LNG ships in the 1990s.

In California, LNG terminal opponents say the state could become more vulnerable to terrorists if terminals are built here.

Long Beach activist Bry Myown said the Long Beach and Los Angeles port complex is already considered a prime terrorism target. She said an LNG terminal would give America’s enemies a powerful weapon because of all the volatile products at the port.

“If anything blows up in that port … it would set off a chain-reaction fire,” she said.

Fay, the MIT professor emeritus, said a small bomb-laden boat – like the one used in the October 2000 terrorist attack on the USS Cole in Yemen – could blow a hole in the side of an LNG tanker.

He said LNG is so highly concentrated and stored and shipped in such large volumes that it holds more potential firepower than other chemicals and petroleum products.

Mark Robinson, the director of the Federal Energy Regulatory Commission’s office of energy projects, said the agency would evaluate all these concerns in deciding whether to permit the Long Beach terminal.

“Safety is the No. 1 concern of the commission,” he said.

Robinson said Coast Guard officials guard against terrorism by inspecting LNG tankers and escorting them into port. He said his agency also seeks to protect the public by limiting its exposure to accidents at onshore facilities.

In addition, he said LNG structures are “robust”: The ships are double-hulled, and the storage tanks are encased in concrete.

Opponents of the Long Beach terminal fear those structures still wouldn’t be strong enough to withstand a major earthquake.

Several earthquake faults are nearby, and the terminal would be built on landfill that a temblor can turn into liquid.

“That could cause the structures to collapse, just like they did in the 1989 earthquake in San Francisco’s Marina District,” said Harvey Y. Morris, the California Public Utilities Commission’s principal counsel.

Giles, the executive advocating the Long Beach terminal, said seismic experts would ensure the terminal is safe. He said Japan has 20 LNG terminals, and none suffered damage in the 7.2 Kobe earthquake in 1995.

Long Beach activists have reached out to environmental groups around the state to argue that all the LNG proposals could impede California’s efforts to increase energy efficiency, conservation and alternative fuel usage.

“We’re not interested in exporting fossil fuels from Third World countries,” said Bill Allayaud, California Sierra Club legislative director. “The Sierra Club stands for conservation.”

Other environmental activists also pointed out that LNG wouldn’t arrive in California for another three to four years under the various project’s timelines – and that might be too late to avoid the next energy crisis.

For Long Beach, though, the proposed terminal would bring cheaper natural gas to heat homes, increased income to the city and the port and clean-burning LNG for their public vehicles.

As a result, the port, some labor groups and some local officials have embraced it.