13/05/2010 (South Sentinel) - If oil from the Gulf spill comes to South Florida, a different scene is likely to unfold from the desperate struggle taking place off the Louisiana coast.

Oil that rides the ocean currents to the waters off Fort Lauderdale and Palm Beach likely will become thick, weathered stuff that will call for defenses other than plastic booms and chemical dispersants sprayed from Air Force C-130s.

The Coast Guard, lead agency for oil spills, has hundreds of pages of contingency plans for oil spills along the southeast Florida coast, but many steps contemplated in these documents are geared more toward tanker accidents than a slow-moving slick from the Gulf of Mexico.

No specific plans have been made by the Coast Guard for the arrival of oil from the Gulf spill yet because too much remains unknown — for example, whether the oil will arrive as a sheen, a sticky mousse or tar balls, and whether there will be a lot of oil or just a few wisps pulled off the main slick.

"At this point we don't have a defined threat, so I can't talk about booming strategy or where we're going," Coast Guard Capt. Jim Fitton told a briefing of elected officials this week at the Broward County Emergency Operations Center. Fitton is commander of Coast Guard Sector Miami, whose area of responsibility includes the entire southeast Florida coast.

"It depends on whether it's an oil sheen or tar balls. Once we know that, we can come up with a response plan," Fitton said.

But Fitton and other officials were able to lay out some strategies and tactics — such as vacuuming tar balls off the ocean floor — likely to be employed if the Gulf threat materializes for South Florida.

The scenario of a threat to South Florida would involve the oil getting caught up in the Loop Current, which runs from the Gulf through the Florida Straits and up the east coast.

At a briefing for public officials Wednesday at Port Everglades, scientists from the National Oceanic and Atmospheric Administration said at least some tar balls are likely to turn up in South Florida, said Broward Mayor Ken Keechl, who attended the meeting.

"It seems to me that to the extent we're affected at all by this, it will be a less severe episode,'' Keechl said. "We won't be seeing oil slicks. It's going to be a tar ball event. I think it's fair to say that the likelihood of an event is more likely than not.''

If winds and local currents aren't driving toward shore, Fitton said, it's possible the oil simply will keep going north and not end up on South Florida's beaches.

An important factor governing the threat and how to fight it is the consistency of the oil. If oil gushing from the ocean floor arrives here quickly, it will look like the greasy sheen in the Gulf. But as oil on the ocean surface bakes in the sun, chemicals evaporate, leaving behind denser and denser material that combines with sea water, forming a mousse or tar balls.

Hard plastic booms, such as the ones laid down across coastlines in the Gulf, would be useless. Tar balls would bob right under them.

Frank Cesario, chief of the contingency planning and force readiness division for Coast Guard Sector Miami, said the Coast Guard would catch tar balls using specialized booms with oil-absorbent surfaces or tendrils that look like shredded trash bags.

Although many people's image of an oil spill comes from the Exxon Valdez disaster in Alaska, Cesario said the arrival of oil from the Gulf into South Florida would be a serious but less catastrophic event.

"That was a massive dump at the surface that came ashore," he said. "This is a different scenario. The poisonous stuff is evaporating and being burned off."

Any tar balls collected could either be disposed of as hazardous waste or — if they haven't absorbed too much seawater — used in asphalt or burned as fuel for a power plant, he said.

Unlike a sheen on the surface, tar balls can sink to the bottom. The Coast Guard is identifying depressions in the ocean floor off southeast Florida that would be likely places for tar balls to collect, Fitton said, with the aim of sucking up the tar balls with undersea vacuums.

The Coast Guard has prepared a detailed atlas of southeast Florida that ranks coastal sites in order of priority, with a triple-diamond symbol marking the sites in most urgent need of protection.

Off southern Palm Beach and northern Broward counties, for example, triple diamonds mark the location of the Gulfstream Reef, a stand of mangroves in Boca Raton and residential canals in Deerfield Beach frequented by manatees. Off southern Broward, high priority spots include reefs inhabited by threatened acropora corals, the seagrasses and manatee habitat around the Dania Cut-Off Canal and the yacht marinas around the 17th Street Causeway.

Key points for protection are the inlets, such as Hillsboro Inlet and Boca Raton Inlet, where tides could allow oil to penetrate coastal and interior wetlands. If oil arrives in South Florida in any quantity, officials said booms likely would block off the inlets.

Eric Myers, deputy director of the Broward County Department of Environmental Protection and Growth Management, said it is important to prevent oil from penetrating the inlets because it would be extremely difficult to remove from mangroves and other coastal vegetation.

Beaches — in spite of the nightmare image of oil spattered along sandy shore — would be a lower priority because they are comparatively easy to clean by removing contaminated sand.

"Beaches can be cleaned up," Myers said. "Plants, marshes, estuaries and mangroves are more difficult."

In the Gulf of Mexico, planes and boats have sprayed about 372,000 gallons of chemicals into the slick to break it up, a procedure that has drawn criticism from scientists and environmentalists concerned about the effect on fish, dolphins and other wildlife. The use of these chemicals could be out of the question in South Florida, home of the largest coral reef tracts in the United States.

Richard Dodge, director of the National Coral Reef Institute of Nova Southeastern University, has told the Coast Guard and other authorities that dispersal chemicals could cause severe harm. The chemicals may be toxic to corals, and more important, by breaking up the oil and distributing it through the water, they would make it more likely that bits of oil would be absorbed by corals.

Fitton said in an e-mail that chemical dispersants aren't particularly effective against tar balls, so they wouldn't be used under the most likely scenarios. NOAA scientists, he said, "are dead set against using dispersants in shallow water, especially over reefs."