Oil pollution & FM&A guest lecture (Week 12)

Question 1

What is crude oil

Answer 1

A complex mixture of hydrocarbons, organic compounds and a small amount of metals

Question 2

Where does oil come from

Answer 2

Tiny flora & fauna organisms die on sea bed covered by layers of sand & silt.
Over millions of years remains buried deeper and deeper, enormous heat & pressure turn them into oil & gas.
Today drill through earth to reach rock formation that contains oil and gas deposits.

Question 3

Sources of oil pollution in tankers

Answer 3

Tanker operations: >1.8 billion tonnes of oil transported by sea annually.
Dry docking
Tanker accidents
General shipping industry

Question 4

Sources of oil pollution in the ocean

Answer 4

Offshore oil production: Oil drilling produces oil containing wastes that are dumped at sea.
Coastal oil refineries: Plants where crude oil is processed to make petrol, diesel etc. produce a waste water that is released at sea.
Licensed dumping at sea: Spoils from dredging ports & shipping channels.

Question 5

Sources of oil pollution before it gets to the sea

Answer 5

Urban runoff: Waste oil from cars, trucks, garages etc. end up in rivers & sea in runoff.
Atmospheric inputs: Engine fumes, oil platforms and evaporation from the cargoes of oil tankers.

Question 6

What was the largest accidental oil spill in history

Answer 6

The Deep Water Horizon Oil Spill that occurred on April 20th 2010 on an offshore oil drilling rig operated by BP.
Estimated 4.9 billion barrels/780 million litres released into ocean

Question 7

What is an oil slick

Answer 7

When liquid oil is spilled at sea and spreads over the surface of the water.

Question 8

How does spilled oil disperse in the ocean

Answer 8

Low molecular weight constituents evaporation
Water soluble components dissolve in water column
Wave action causes emulsion also determines oil movement

Question 9

Where can oil disperse to after a spill

Answer 9

Some components sink to seabed and incorporate into sediments
Naturally occurring microorganisms can biodegrade on some constituents of oil
Some constituents oxidise when interact with air
- higher molecular weight fractions form tar balls (1mm - 20cm)

Question 10

The rate at which oil spreads, is biologically degraded and the extent of the environmental damage that it causes depends on what factors:

Answer 10

Nature of spill: composition, duration, quantity
Environmental conditions: Air?water temp, weather, time of year.
Species composition of the area
Shoreline properties (rocky, sandy, mudflat, mangroves)
Amount of oil-degrading micro-organisms in the area
Supply of oxygen in the water

Question 11

What measures were taken to suppress the effect of the Deepwater Horizon Oil Spill

Answer 11

Some oil captured by efforts to contain the spill
Some burned or skimmed from surface
Some dissolved or evaporated
Some naturally and chemically dispersed
Some still at sea

Question 11

What measures were taken to suppress the effect of the Deepwater Horizon Oil Spill

Answer 11

Some oil captured by efforts to contain the spill
Some burned or skimmed from surface
Some dissolved or evaporated
Some naturally and chemically dispersed
Some still at sea

Question 12

What happened in May 2010 after the Deepwater Horizon Oil Spill

Answer 12

In May 2010 large plumes of oil found underwater. 10 miles ling and 3 miles wide

Question 13

What happened in June 2010 after the Deepwater Horizon Oil Spill

Answer 13

Oil hit the coast of Florida.
Slick and tar balls hit Mississippi, Louisiana, Alabama, Texas & Florida.

Question 14

What happened in August 2010 after the Deepwater Horizon Oil Spill

Answer 14

oil deposits that matched the Deepwater Horizon spill found on the seabed.

Question 15

Why mitigate oil damage at sea

Answer 15

Its easier to deal with at sea before it hits the coast
Oil skimmers collect slicked oil that an be deflected away from sensitive sites.
Contained oil is burned and residue collected and disposed of

Question 16

What can be used to break up oil slick

Answer 16

Chemical dispersants to speed up emulsification process.
Dispersants may harm naturally occurring mocrobes that help breakdown oil.

Question 17

What is bioremediation

Answer 17

The removal of pollutants by micro-organisms

Question 18

What is Biostimulation

Answer 18

Addition of nutrients to speed up the process of biodegradation on oil

Question 19

How do oil eating microbes work

Answer 19

The microbes break apart the hydrocarbons and combine them with oxygen to create water and carbon dioxide.

Question 20

What does adding fertilizers to oil eating microbes do

Answer 20

Can increase the size and number of of microbes to eat more oil. Too much can cause algae blooms which will starve the ecosystem of light and oxygen

Question 20

What does adding fertilizers to oil eating microbes do

Answer 20

Can increase the size and number of of microbes to eat more oil. Too much can cause algae blooms which will starve the ecosystem of light and oxygen

Question 21

How much toxic chemical dispersants were used in response efforts to the Deep Water Horizon spill

Answer 21

1.8 million gallons.
BP were criticized for not using the least toxic dispersant available

Question 22

What did people use in the gulf of Mexico to clean up marshland habitats from oil spill

Answer 22

Booms, Vacuums and ‘Slick lickers’

Question 23

Why did US Government call for clean up efforts in the Gulf of Mexico to be scaled back

Answer 23

Further cleanup operations may disturb sensitive wildlife posing a greater environmental risk than leaving oil residue there.

Question 24

What are PAHs

Answer 24

Polycyclic Aromatic Hydrocarbons.
They are a class of chemicals that occur naturally in crude oil

Question 25

The impact of oil pollution is two fold:

Answer 25

Kill by smothering organisms
Contains compounds toxic to marine organisms

Question 26

The impact of oil pollution is two fold:

Answer 26

Kill by smothering organisms
Contains compounds toxic to marine organisms

Question 27

What is CYP1A

Answer 27

PAH exposure ‘turns on’ CYP1A gene which triggers production of CYP1A protein. This protein breaks down PAHs

Question 28

What effect does oil pollution have on seabirds

Answer 28

Feathers soaked in oil lose water repellent properties.
Water penetrates plumage displacing layer of air between feathers and skin resulting in loss of thermal insulation
Swallowing small amounts of oil depress egg laying and hatching success.

Question 29

What effect does oil pollution have on commercial fisheries

Answer 29

Fish eggs & larvae vulnerable - leads to low recruitment of species
Fish & shellfish in aquaculture installations cannot escape contaminated waters.

Question 30

What is the estimated world input of petroleum hydrocarbons to the sea per year.

Answer 30

Atmospheric emissions most with 3.750
Tanker accident - 0.162
Non tanker accidents - 0.020
Ocean dumping least with 0.02

Question 31

How much fishing grounds in the gulf of mexico was closed

Answer 31

36%,

Question 32

What are the indirect impacts of oil pollution

Answer 32

Chemicals used to clean up can kill organisms
Oil eating microbes can consume oxygen creating dead zones
Can change community structure in phytoplankton

Question 33

What is NRDC

Answer 33

Natural Resources Defense Council

Question 34

How many birds, sea turtles an mammals were affected during the spill and cleanup phase

Answer 34

997 birds dead
>1000 sea turtles dead
51 mammals including dolphins collected in spill zone, 47 dead

Question 35

What species of sea turtles were found stranded in the north central gulf of Mexico

Answer 35

More than 2000 turtles
Kemp’s turtles
Loggerheads
Green turtles

Question 36

What is UME

Answer 36

Unusual Mortality Event

Question 37

What disease in dolphins is consistent with exposure to petroleum compounds

Answer 37

The rare, life threatening and chronic adrenal gland and lung diseases identified in UME dolphins

Question 38

What effect does dolphins diagnosed with moderate - severe lung disease have on reproduction

Answer 38

Only 20% of pregnant dolphins produced viable calves
57% of pregnant females did not successfully produce a calf

Question 39

When did the Exxon Valdez oil spill occur

Answer 39

March 24 1989
Only 14% oil spill removed of 37,000 tonnes