What factors affect water pollution?
-The size of the emission
-The rate of the emission
-The volume of water being polluted
-The residense time of the water
-Dispersal rate by currents
Give examples of common water pollutants
-Heavy shipping (Oils, ship fuel)
-Industrial coolant water (Heated water raising the temp of the body of water)
-Leaching of agricultural nitrates and phosphates
Give examples of causes of oil pollution
-Vehicle engine lubricating oil that leaks or is deliberately discharged into the environment.
-Industrial machine oil that is washed into drains or mixed with other effluents
-Grey water from the washing of ship oil tankers' tanks
-Tanker or ship accidents at sea
-Discharging of ship bilge water
-Accidental spillages from oil refineries, storage facilities or pipelines through damage/ fractures in the pipeline
-Leaking during exploration, drilling and extraction from oil platforms.
What are some effects of oil pollution?
-Some components of oil are extremely toxic and poison organisms
-Oil asphyxiates shorelife such as molluscs and seaweeds
-Seabirds will become coated, and eventually starve or become asphyxiated, or die of hypothermia
-Oil that is swallowed by organisms will hinder digestion and cause death by starvation
-Reduce survival rate of seabird chicks (more time is spent by the adults preening, and therefore less time is spent looking after and collecting food for the chicks)
-Can prevent oxygen entering the water
-Marine organisms that communicate with scents (finding a mate, finding food etc) can have difficulties in smelling anything other than the oil
Define ''point sources''
Effluent emissions that come from a small number of sources that are usually easily identifiable.
Define ''Non-point sources''
Effluent emissions that come from a variety of sources which are usually difficult to identify.
Give an example of a point source
-Oil spills from tankers
-Major/ minor identifiable tanker/ ship accidents
-Major fractured pipeline accident
Give an example of a non-point source
-Oil leaking from cracks in the seabed
-Bilgewater discharging from a variety of different ships
-Minor leakages from pipelines
How might oil pollution/ oil spillages be controll
Recycling waste lubricating oil. (Either to make new lubricating oil or burning it as a fuel)
Equipment maintenance should reduce the probability of leakages
Bund walls, which oil storage tanks are built on. These would contain the oil if the tank were to split.
Improved ship tanker design.
Improved ship tanker operations
How might an oil spill be cleaned up?
Inflateable booms used to limit the spread of oil slicks
Skimmers. These are roating wheels which the oil sticks to.
Absorbent materials such as straw and fibrous plastic mats can be spread on the oil.
Polymerising chemicals can be spread on the oil.
Chemical dispersants such as detergents can be used to break up and disperse the oil.
Beaches can be cleaned by volunteers.
Boiremediation is the application of oil- digesting bacteria. this is usually only effective in warmer climates.
Beaches can be cleaned with hot water or steam.