Quiz: How Much Do You Know About the Gulf Oil Spill?
Photograph by James Balog, Aurora Photos
You probably know that the 2010 explosion at Deepwater Horizon caused the worst oil spill in U.S. history, but how much do you really know about the accident's magnitude and effects?
By how much did BP and the U.S. government underestimate the rate at which oil was spilling from the Macondo site in their first calculation?
- By a factor of 12
- By a factor of 25
- By a factor of 30
- By a factor of 60
In the first days after the Deepwater Horizon explosion, the joint task force estimated that oil was spilling by 1,000 barrels per day. But after the well was capped, the U.S. government used pressure readings and other data to determine that early on, 62,000 barrels per day had been leaking from the well.
How does the total amount of oil that spilled from BP’s Gulf of Mexico well in 2010 compare to the amount of oil consumed daily around the world that year?
- The spill amounted to less than 1 percent of daily global oil consumption.
- The spill amounted to about 6 percent of daily global oil consumption.
- The spill was about half of daily global oil consumption.
- The spill was 30 percent more than global daily oil consumption.
Authorities say about 5 million barrels of oil spilled from BP’s well. That is nearly 6 percent of one day’s global oil consumption of 85 million barrels.
Oil typically floats on water, a fact that scientists have long relied on in estimating the size of oil spills. But why did the plumes of oil stay underwater at the BP well site?
- Strong ocean currents kept them trapped in place.
- The type of oil leaked in the Gulf is especially dense and did not rise.
- Dispersants broke oil into droplets suspended by equally dense water.
- The density of the water was equal to the density of oil because of the depth of the wellhead.
Scientists believe the plumes were caused in part by the unprecedented amounts of chemical dispersants injected near the leaking Deepwater Horizon wellhead.
Of the following major oil spills, which one was the smallest?
- BP, Gulf of Mexico, 2010
- Exxon Valdez, Alaska,1989
- Ixtoc, Gulf of Mexico, 1979
- Persian Gulf war, Kuwait, 1991
The size of the Exxon Valdez tanker spill in Alaska’s Prince William Sound, about 259,500 barrels, pales beside the others. Ixtoc’s 3.3 million barrels was eclipsed by BP as the Gulf of Mexico’s largest ever spill. But the largest spill of all time, at least 6 million barrels, resulted from the deliberate sabotage of Kuwait’s oil fields by Iraq’s retreating troops in the first gulf war.
What was the “root technical cause” of the BP well blowout, according to the chief counsel’s report of the National Commission on the BP Deepwater Horizon Oil Spill?
- The cement pumped to the bottom of the well did not seal off the oil and natural gas.
- The blowout preventer failed to seal off the oil and natural gas.
- The heavy drilling mud failed to counterbalance the pressure of the oil and natural gas.
- The depth of the well caused the oil and natural gas pressure to be too high.
The cement job was the root technical cause, said the report. It noted that while the exact reason for the failure will never be known, there was a low overall volume of cement, and the slurry was poorly designed and unstable. The report concluded BP failed to back up the cement job, or to recognize the failure during a pressure test the day of the blowout.
One way authorities sought to control the oil was by surrounding the slick with fire booms and burning it off. What percentage of the oil was removed by these in situ burns?
- 1 percent
- 5 percent
- 10 percent
- 20 percent
Authorities estimate 265,000 barrels of oil were removed through in situ burns, or about 5 percent of the total 4.9 million barrels spilled.
Which of the following is a new offshore drilling requirement that has been put into place by the U.S. government since the BP spill?
- Blowout preventers especially designed to withstand the high pressure of deep-sea wells.
- Remote-control acoustic shut-off switches for blow-out preventers.
- Certification by a professional engineer that a well casing and cementing plan is appropriate for the expected well pressure.
- All of the above
The U.S. Department of the Interior’s drilling safety rule, put into place in October, aimed at improving well-bore integrity by requiring such steps as professional certification of well cementing plans. But the government is still investigating what modifications should be made to the design of blowout preventers so that they can better withstand high-pressure wells.
The state bird of Louisiana, the brown pelican, became the spill’s “poster child,” because it had been taken off the U.S. endangered species list just five months before the oil hit. How many brown pelicans did the U.S. Fish and Wildlife Service document were killed by the spill?
About 900 brown pelicans were confirmed to have been killed by the oil. But the National Audubon Society warns the birds are returning to nest in areas that are still contaminated with oil, and the extent of the damage to their food supply remains to be seen.
On the one-year anniversary of the Deepwater Horizon explosion, scientists still don't know the extent of the oil spill's effects on most species. But for one of the following species, the U.S. Fish and Wildlife has only documented two deaths due to the spill—which one?
- Sea cucumbers
- Bottlenose dolphins
- Wilson's plovers
- Sea turtles
Only two Wilson's plovers were among some 8,000 birds known to have been affected by the spill. But many more undoubtedly perished. As for sea cucumbers, scientists have found an “invertebrate graveyard” at the bottom of the sea due to the oil. A year after the oil spill, they are also investigating the cause of large numbers of dolphin and sea turtle deaths.
Overall, 1,053 miles (1,694 kilometers) of coastlines in Mississippi, Louisiana, Alabama, Florida, and Texas are known to have been blackened by the BP disaster. How much area remained heavily or moderately oiled at the start of this year?
- 1 mile (1.6 kilometers)
- 8 miles (13 kilometers)
- 80 miles (129 kilometers)
- 800 miles (1,287 kilometers)
The Natural Resource Damage Assessment, a government research process that's required following oil spills, reports that 83 miles (134 kilometers) remained heavily or moderately oiled as of January. Florida beaches now appear to be entirely clean, due to responsive bacteria, calm weather, and aggressive cleanup efforts, scientists say.
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