Hobbies And Interests
Mechanical
Spilled oil from an oil tanker or from an ocean bed well spreads over the ocean´s surface. The first line of defense is containment to prevent this spread. Booms and barriers placed around the accident site contain the oil or direct its movement. Floating booms stop waves from splashing the oil over its sides. Some of these have an underwater "skirt" that prevents the oil spreading under the boom. A chain is attached to the skirt in rougher seas to weight it down and keep the boom upright. Booms are not very effective in high waves.
Chemical
Chemicals that disperse oil prevent it from reaching beaches. These dispersents contain surfactants that break oil down into small droplets that are then further broken down by wave action. This method is ineffective with crude oil, gasoline and diesel, so it is only used in specific circumstances, such as a petroleum oil spill. Dispersants work better in warm water than in cold and are most often used in rough sea conditions. The Environemental Protection Agency prohibits the use of dispersants in freshwater because of the potential damage to human health.
Biological
Along the shoreline and in environmentally sensitive areas adjacent to the shorline, such as marshes and wetlands, workers use biological agents to clean up the oil. These speed up the natural biodegradation process that would otherwise take years. Fertilizers add nutrients such as phosphorus and nitrogen to the contaminated area and breed microorganisms that increase the rate of biodegradation.
Physical
Once an oil spill hits the shoreline, workers use physical clean up methods. These include wiping with sorbents. These are sponges made from a diaper like material. Raking and bulldozing the beach also helps, and pressure washing it sends oil back into the sea where it is skimmed up. However, some criticize this method for causing more destruction to beaches in the long term. Keeping as much wildlife as possible away from the spill area is another part of the clean up process. Using helium-filled balloons, floating dummies and propane scare cans are all effective methods of keeping birds away.