Why Oil Spills Occur

• Oils spills typically occur when something goes wrong during the transport of oil to and from refineries, oil tankers, pipelines, barges and distribution or storage facilities. Natural disasters, such as hurricanes, can also cause oil spills, and sometimes the spills can be the result of sunken ships, illegal dumping or even sabotage by countries at war. The oil spreads over the sea surface, causing slicks or a rainbow-colored sheen. The oil and water will sometimes emulsify and form a type of high-viscosity mousse that can in turn cause tar balls, which can travel great distances at sea or end up on the shoreline.
  
  

Effects of Oil Spills on Beaches

• Large oils spills are very harmful to wildlife. This includes birds, marine mammals, fish and shellfish. Oil spills also can affect an area's cultural, economical and natural resources. Even smaller oil spills can be very harmful if spilled in the right place in the right time. Oil can penetrate deep into the sand on beaches, making it difficult to remove and enabling the oil to continue to cause problems over time. Oil spills are easier to clean up when they are on a rocky coast as opposed to a soft and marshy shoreline or delta. Oil is more likely to stick to rocks, making it easy to see and to clean. Once the oil sinks into marshland or wet sand, there is a greater chance that it will not be completely removed from the area.
  
  

Effects of Types of Oil

• Different types of oil have different effects on beaches and oceans when spilled. Determining what type of oil was spilled is the first and most important step in deciding how to proceed with the cleanup. The persistence of an oil is important to note, since oils of different persistence are handled differently.
  
  Nonpersistent oils, such as gasoline, are light and refined, which makes them highly volatile. Their highly volatile nature means they evaporate and disperse quickly, making most cleanup efforts unnecessary. Unfortunately, in colder regions, the oil sticks around longer because it cannot evaporate as quickly as it would in a warmer region. However, these types of spills can also be dangerous due to the highly flammable nature of gasoline and the health concerns that may arise from breathing in the gas, especially if the spill occurs near a highly populated area of land.
  
  Heavy oils are more persistent when spilled because they have such a high viscosity and are not volatile. Bio-fuel oils are also very persistent and create sludge and heavy slicks that can remain in the environment for long periods of time.
  
  

Oil Spill Cleaning Techniques

• The techniques used to clean oil spills vary depending on the type of oil and where and how much was spilled. Large booms may be placed in the water to prevent spreading and keep the spillage contained. These are especially used during oil tanker spills. Skimmers remove the oil from the surface of water, while vacuum trucks vacuum the oil off the water surface and shoreline. Sorbents are used to absorb oil, while high- or low-pressure hoses are brought in to hose off sandy beaches and other parts of affected shoreline. Sometimes the oil is purposely set on fire to burn off as much of a fresh oil spill as possible. Wildlife is corralled away from the area using scare tactics or other diversions.
  
  Occasionally, the best response is no response at all. This is true in some rare situations when interfering with the spill would cause more harm than good.