oceans and oil spills. history of the gulf oil spill explosion kills 11 men on rig on april 22, 2010...
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Oceans and Oil Spills
History of the Gulf Oil Spill• Explosion kills 11 men on rig on April 22,
2010• The Entire rig sinks on April 23, 2010• A customized containment cap was fitted to
the well in early June, – Oil was piped to the Discover Enterprise
vessel. • A second containment system was installed
in mid-June, using a manifold and hoses to carry oil and gas to the Q4000 vessel on the surface.
• On July 12, a new sealing cap was installed • On July 15, a well integrity test began in
which the cap’s three ram capping stack was closed, effectively shutting in the well and all sub-sea containment systems.
• On August 5, BP completed cementing operations at the MC252 well, as part of the static kill procedure.
• The relief well drilled by the DDIII drilling rig intercepted the annulus of the MC252 well on September 15
• Pumping of cement into the annulus on September 17, permanently sealed the well.
This Spill in Context (6 largest previous Spills)
June 3, 1979, 4.2- 12.5 million gal
November 1, 1979, ~2.6 million gal spilled, 7.8 million galburned
June 8, 1990, 5.1 million gal.
July 30, 1984, 2.7 million gal
August 10, 1993, 336,000 gal
August 8, 2005, >8 million gal in 250 reported spills
Active Oil Platforms in Gulf
Oil Pollution in our Oceans• 3.25 million metric tons of
petroleum annually• Human Sources
– Leaks at marine terminals– Disposal of drilling muds
from offshore operations– Municipal and industrial
wastes– Urban runoff into rivers– Atmospheric fallout from
the incomplete combustion of oil in motor vehicles
Exxon Valdez Oil Spill
• Exxon Valdez– 11.6 million Gal Spilled
• Horizon Spill– 210,000–4,200,000
gal/day
How Much Oil was spilled?
• Used optical plume velocimetry to estimate the velocity of fluids escaping the damaged well,
• Average flow rate from 22 April to 3 June– 5.6 x 104 ±21% barrels/day
• After the riser was removed– 6.8 x 104 ±19% barrels/day
• Taking into account the oil collected at the seafloor– 4.4 x 106 ±20% barrels of oil was
released into the ocean– ~1.8 billion gal.
• Crone, TJ & Tolstoy, M, 2010 Science
What happens in typical oil spill?
Mousse
Clean-up process
• Use Dispersants• Collect with boom and
scoop out of ocean• Burn it
Gulf Oil Spill
• Escaping oil sprayed with dispersant at well head– Produced tiny droplets
of oil in deep ocean
• Surface oil– Collected with booms– Burned
The “Loop Current”
• Initial concerns that the surface oil would enter the loop current
• Winds helped to contain the oil
Gulf Stream from Satellite
Hurricane Impacts on Oil Spill
• Hurricanes are likely to disperse remaining oil further
• Potentially oil can be driven onshore through the storm surge
• BP States that deep water oil is in ppm and should not be significant
Hurricane effects on oil spill
• Position and approach of hurricane will effect potential damage
• Right side of hurricane can bring significant oil ashore
Gulf Oil Spill Clean-up
• Escaping oil sprayed with dispersant at well head– Produced tiny droplets
of oil in deep ocean
• Surface oil– Collected with booms– Burned
Shore Clean-up Methods
• Can Spray water on shore– Drives oil into
sediment– Hot water kills micro-
organisms
Meiofauna in Beach Environments
• Microscopic invertebrates that live in beach sands
• Base of the food chain
Meiofauna
Pelagic Organisms
• Nekton may be able to avoid oily areas
• Plankton are unable to move away
– Plankton-floaters– Nekton-swimmers
Benthic Organisms
• Organisms that live on the ocean bottom
• Typically in shallow water– 2 types
• Sessile-Cannot move to avoid oil
• Vagile-may be able to crawl or swim short distances to escape oil residue
Turtle Strandings on Gulf Coast
• Green is confirmed• Red are new
strandings• Too soon to tell
how many are from oil
• Numbers may be inflated
Sea Turtles Collected since Spill
Dead (5% oiled) Live (85% oiled)
Oiled
No Oil
Oiled
No Oil
Sea Turtles Collected by State
Florida Alabama Mississippi Louisiana Texas On Water0
50
100
150
200
250
300
350
400
450
500
Live
Dead
Marine Mammal Strandings
Mammals Collected
Dead (4% Oiled) Live (22% Oiled)
Oiled
No Oil
Oiled
No Oil
Mammals Collected Since Oil Spill
Florida Alabama Mississippi Louisiana Texas On Water0
10
20
30
40
50
60
70
Live
Dead
Volunteer Groups Capture Oiled Birds
• Brown pelicans are particularly susceptible
• Dive into water • Feathers become coated
with sticky mousse• Too heavy to fly• May die of
– exposure– starvation– drowning– exhaustion Gulf Coast oiled bird
Birds Collected since Spill
Dead (37% oiled)
Oiled
No Oil
Live
Oiled
No Oil
Note: Only live birds that were in distress were collected.
Number of Birds Collected
Florida Alabama Mississippi Louisiana Texas On Water0
500
1000
1500
2000
2500
3000
3500
Live
Dead
Fishing Closures
October 5, 2010 October 22, 2010
Oil in the Water Column
• Dispersant caused oil to remain at depth
• Natural bacteria eats oil
• Oxygen is depleted at depth
Normal Oxygen Levels in the Ocean
BP’s Response• Amount Spent
– Over $8 billion spent to date– $20 billion claims escrow
fund– $100 million unemployed rig
workers' fund– $500 million establishing Gulf
Coast Research Initiative• Containment
– 827,926 barrels of oily liquid skimmed
– 265,450 barrels in controlled surface burns
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