Deepwater Horizon Oil Spill (Excursions)

Workout

A. Fill in the blanks.

1. An oil spill refers to the release of liquid petroleum into the seas and oceans.

2. An oil spill is a human-made disaster.

3. Deepwater Horizon oil spill occurred on 20 April, 2010.

4. Blowout is the uncontrolled release of crude oil or gas.

5. Rhodoliths are rich seaweed assemblages.

B. Fill in the blanks with the correct answers.

1. ............... is the largest global oil and gas company.

a. Bharat Petroleum. [ ]
b. British Petroleum. [✓]

c. American Petroleum. [ ]

d. PetroChina. [ ]

2. A ................ is a device attached to a pipe or a tube which controls the flow of a fluid.

a. valve. [✓]
b. blowout preventers. [ ]

c. tube. [ ]

d. propellers. [ ]

3. The borehole at the bottom of the rig is capped with ............. to prevent leakage.

a. marble. [ ]

b. cement. [✓]

c. concrete. [ ]

d. limestone. [ ]

C. Give reasons for the following.

1. The oil spill of April 20, 2010 is known as Deepwater Horizon Disaster.

= The oil spill of April 20, 2010 is known as Deepwater Horizon Disaster because it was an explosion on the Deepwater Horizon Macondo oil well. It killed 11 workers and started the largest marine oil spill in world history, releasing millions of barrels of oil into the Gulf of Mexico.

2. Oil spills adversely affect the ecosystem and the marine life.

= Oil spills adversely affect the ecosystem and the marine life because it pollute the water. The see animals can not breathe properly. Fish get oil in their gills sea birds get oil in their wings. Sea animals get major health issues.

3. It is difficult to clean up oil spills.

= It is difficult to clean up oil spills because oil separation is done manually and is more effective in water bodies with less undercurrent. The strong undercurrent make cleaning method difficult.

D. Answer these questions in detail.

1. What was the cause of the oil spill in the Gulf of Mexico?

= According to experts, eight disastrous failures led to the explosion that destroyed the oil rig. This incident occurred because of several technological failures rather than a single one.

❐ Construction material : The borehole at the bottom of the rig was capped with cement to prevent any leakage. The gas and oil began to leak through it into the pipe flowing to the surface.

❐ Valve : A valve is a device attached to a pipe or tube that controls the flow of air or liquid. This device stops, stars or controls the flow of fluid. The pipe that is used to extract oil contains two such mechanical valves. A fault in the valve led to the leakage of methane gas to the surface of the oil rig.

❐ Misinterpretation of pressure data : The staff on duty on the oil rig had carried out various pressure tests to find out whether the  valve was operating properly. However, they failed to detect the fault in the valve. They had incorrectly analyzed that the well was properly sealed.

❐ Delayed response : The crew at the surface failed to notice the flow of oil and gas  towards the surface. The oil leak was discovered only two days after it actually started.

❐ Gas alarm : The on-board gas detection system that was supposed to trigger warning failed to work.

❐ Battery failure of the blowout preventer : The explosion destroyed control lines, which the crew was using to close the safety valves. However, the blowout preventer did not work. The entire sequence of activity led to the explosion that destroyed the Deepwater Horizon oil rig.

2. What are blowout preventers?

= Blowout preventers are a large, specialized valves or similar mechanical devices, used to seal, control and monitor oil and gas  wells to prevent blow out.

3. What was the impact of the Deepwater Horizon oil spill on the marine life?

= The area affected by the oil spill was home to 8,332 marine species, comprising fish, birds, octopuses, sea turtles and marine mammals. This spill harmed around 39 marine species, which is a threat to the marine ecology. The impact on the corals was devastating. Scientists have found evidence of widespread damage of the corals deep in the sea. Some of these corals were more than 600 years old. They have a slow growth rate and longevity, which makes them extremely vulnerable and slow to recover form any adversity. Rhodoliths are rich seaweed assemblages. These provide habitat for deep-sea shrimps, crabs and lobsters. Many of these Rhodoliths died after the oil spill. The oil spill also affected many marine mammals. It is estimated that nearly 170 marine mammals died. The oil spill caused life threatening diseases and many deaths. The bottlenose dolphins exposed to oil were afflicted with moderate to severe lung disease. More than 1000 sea turtles were found dead in the oil spill. Marine birds including seagulls, pelicans, roseate spoonbills, egrets, terns and blue heron were affected by the spill.

4. Which methods were employed to clean the Deepwater Horizon oil spill?

= The following methods were employed to clean the Deepwater Horizon oil spill :

❐ Water-oil separation : Hundreds of workers were deployed to separate oil from water. Oil separation is done manually and is more effective in water bodies with less undercurrent. The Gulf has a strong undercurrent, which made cleaning by this method difficult.

❐ Controlled burning or in situ burning (ISB) : It is a technique of responding to an oil spill. This involves the controlled burning of oil that has spilled from a vessel, at the location of the spill. It significantly reduces the amount of oil on the water and minimizes the adverse effects of the oil on the environment.

❐ Chemical dispersants : Dispersants are chemicals that break oil slick into very small droplets. They are sprayed onto the spills by specially equipped boats or planes. Dispersants are one of the several tools available to combat oil spills.

❐ Bioremediation : The naturally occurring microbes that can be used to process crude oil are known to exist in the ocean. Bioremediation is a process that utilises bacteria, fungi and green plants to naturally remove the contaminations.