In recent years the public has become more focused on what has been incorrectly perceived as the lack of preparedness for oil spills on subsea drilling platforms. This became a very important factor in the Deepwater Horizon oil spill in the Gulf of Mexico that ultimately resulted in the largest marine oil spill in history, estimated to be 4.9 million barrels.
This single spill impacted all of the Gulf States from Texas to Florida, impacting tourism, fishing and ecological reserves throughout the coastal region. One of the biggest issues with this appeared to be the lack of a plan for oil spill containment as well as managing the damaged wellhead.
However, there have been other oil spills, including the Ixtoc I oil spill in 1979 in the Bay of Campeche also in the Gulf of Mexico. Smaller spills occur on subsea drilling platforms, but most are effectively contained and the oil is then collected in skimmers and removed.
Containment Basics
The first priority with any type of marine oil spill is to protect any type of fragile or sensitive environments. This includes preventing oil from moving on the surface of the water, particularly towards wetlands and beaches or other types of protected areas.
Booms can be deployed around the area of the oil spill. The smaller the spill surface, the easier it will be to provide maximum containment of the surface oil. Some booms are very flexible and can be deployed to form a complete circle, literally enclosing the oil and allowing skimmers to be used to draw the oil off the surface and onto ships where it can be removed for further processing.
Boom Types
The most common types of booms or barriers in use today are hard booms. These are narrower at the top with a wider bottom that is heavier to keep the boom in place. The idea with this is to create a structure the oil cannot get past. These can be a good option for oil spill containment in quiet water, but they are of little value with significant waves.
Sorbent booms are designed of a material to absorb the surface oil. They are effective on small spills but ineffective with larger spills due to the amount of oil and the limited capacity for absorption.
New designs for oil spill containment include a durable boom or solid structure that is designed to stop waves but to allow surface oil to flow into the center of the boom through specially designed holes that sit at the water level. The oil in the interior can then be pumped into holding tanks on vessels and removed, while the water that may come in with the oil is simply returned to the area free of any oil.
