The BP Gulf of Mexico oil spill of April 20, 2010 at the Deepwater Horizon Rig in Mississippi Canyon 252 is a historic, economic, environmental, engineering and scientific event of major significance. The spill is already one of the greatest man-made and natural disasters in American history with hundreds of thousands gallons of Louisiana crude streaming daily into the Gulf waters from one mile below. Deepwater Horizon is an ongoing story that involves: an exploded oil rig, 11 dead workers, a damaged riser pipe, multiple attempts by robots to control and cap the damaged pipe and BOP (Blow Out Protector), oil contamination of living and non-living things, and underwater oil plumes. Scientific inquiry investigates the story and controversies of underwater oil plumes.
Oil, Water and Oil Dispersants Mix Well
Oil dispersants are useful to separate or dissociate large masses of oil into smaller patches. The EPA has approved 18 different dispersant products for oil spill situations similar to BP's Deepwater Horizon spill in the Gulf of Mexico.
BP is using Nalco's COREXIT dispersant at the damaged BOP site. Here escaping oil actively mixes with BP's pumped-down dispersant about 5000 feet below the Gulf's water surface. The oil and dispersant interact with the saltwater to form a oil-dispersant-water combination or mixture. The complex oil-dispersant-water mixture is too heavy to float completely upward, but not heavy enough to sink down to the bottom. Therefore, the oil plume remains in the water column.
Any oil that floats to the surface has not mixed with dispersant or has separated from the dispersant. Floating oil has a lower density than water. This oil remains on the surface unless a dispersant is dropped onto the oil by aircraft or from dispersant boats (see photos). When this is done the oil will sink below the surface as shown in the flask experiment photo (click on photo to enlarge and see sequences).
Oil Plumes are Oil-Dispersant-Water Mixtures
Despite protestations from some, oil plumes are very real. These oil plumes have been independently observed and proven to exist. Forensic oil and dispersant chemical analyses of different Gulf oil plume samples can reveal the true nature and source of these documented oil plumes. Jane Lubchenko, Head of NOAA, held a briefing in Washington (Npr.org) and confirmed that one oil plume, some 3000 feet deep and 40 miles northeast of the Deepwater Horizon drill site, represents oil from the BP rig accident.
Oil plumes are made even more real when there are large masses of oil mixed deep down in the water with massive amounts of dispersants as has occurred in the BPO oil spill of 2010. These oil plumes can migrate and be carried far and wide by various underwater currents.
What Happens to Oil Plumes?
As plumes travel within water columns they tend to separate or dissemble into smaller and smaller pieces or fragments. Various plumes that form are complex combinations of different amounts and types of the original crude oil, saltwater and dispersant. Some of the oil breaks free of dispersant and floats to the surface. Some of the plume mixture attaches to living seaweed, phytoplankton, zooplankton, fish, shrimp and other life forms.
Some of the plume mixture attaches to dead organic matter such as submerged wood, dead animals and plants. Some of this oil complex settles downward toward the bottom of the Gulf and other portions of oil and oil-dispersant move to beaches, marshes and waterways where they make landfall. Some of the smaller plume combinations are digested by microbes. Some of the plume complex is ingested by crabs, shrimp, and fish. Some contaminated fish may be eaten by pelicans, gulls and other Gulf birds.
Oil Plumes and Oil Disasters
There are "acts of God" such as hurricanes, tornadoes and earthquakes — events that are totally beyond human control. And there are "acts of man (or humankind, if you like)" such as this 2010 oil spill in the Gulf. All these events create multiple frightening and pitiful scenes of distress. All of these different disasters are events that humans suffer with, can recover from, and even learn from. For example, in earthquake-prone regions of the Western U.S. Coast and in Japan, engineers have learned how to construct better and safer habitations, roads and bridges.
Humans who drill deep in the oceans, seas and various Gulfs throughout the world need to assure their brethren that they have learned how to better avoid, prevent and control huge oil spills. There is much more to learn and much more to do before deep water oil well drilling resumes in the Gulf. This sad story of Deepwater Horizon makes all of this very clear — especially to those who see these ominous, dark, and oiled waters of the Gulf of Mexico on June 11, 2010.
Resources
EPA.gov. Guide to Using the NCP Product Notebook. Accessed June 11, 2010.
EPA.gov. National Contingency Plan Product Schedule Toxicity and Effectiveness Summaries. Accessed, June 11, 2010.
Donald Reinhardt - Think, read, write & live well always. DJR has a PhD in Biology/Microbiology & is a Fellow & Diplomate, ASM Amer Acad Micro.
Join the Conversation