Water Pollution Flashcards
What is acid rain?
precipitation that contains high levels of nitric and sulfuric acids
Can acid rain be any form of precipitation or just rain?
Any
What is the usual pH of acid rain?
~4.2-4.4
What is the usual pH of normal rain?
~5.6
What are the causes of acid rain?
- rotting vegetation
- volcanoes erupting
- primarily manmade
– coal burning powerplants
– factories
– automobiles
Why is acid rain an issue?
- Nitrogen Oxides in acid rain contributes to the formation of ground-level ozone
– Major pollutant, harmful to people - Nitrogen oxides and sulphur oxides are both environmental and health concerns
– Spread easily
— Via air pollution and acid rain - makes water more acidic
– results in more aluminium absorption from soil which is carried into lakes and streams
—- the combination makes water toxic
—— carries throughout food chain out of water
-Also damages forests
— especially high elevation
—- acid rub soil of nutrients, making it harder for trees to take up water
—— makes trees and plants unhealthy and vulnerable boy
what can be done about acid rain?
Curbing release of pollutants that causes it
what is BOD?
Biological oxygen demand
The BBOT of sewage is the amount of oxygen it would use up if released directly into a river or lake
why is it important BOD is reduced before sewage is released into bodies of water?
The removal of oxygen from the water would cause problems for the organisms living there
what is effluent?
A discharge of liquid water
Stages in sewage treatment plant
1) sewage outfall
Sewer pipes bring waste water from home
2) screening tank
Large objects removed from waste using a course grid
3) first settling tank
Solid organic matter is allowed to settle to the bottom of the tank called sludge treated in sludge digester the clean water overflows sides and goes to the next stage
4) oxidation pond
Water pumped into tank where oxygen is bubbled through it. This encourages bacteria growth and other microbes. They break down dissolved organic material which causes the BOD.
5) second settling tank
Water enters here where bacteria settles to the bottom forming more sludge. clean water overflows sidesas effluent
6) effluent discharge
Affluent discharged into environment, usually a river
7) sludge digester
Oxygen Free conditions are created that encourage the growth of bacteria which breaks down the sludge releasing methane which can be burnt
8) the treated sludge can be dried in sludge lagoons and use as organic fertiliser on farmland
What does cutlass stand for? (graphing rules)
cross
unit
title
labels
axis
scale
smooth
curve
how do we treat domestic water?
It goes through a process called coagulation where it’s filtered and disinfected
explain coagulation
Makes particles and water stick together and settle at the bottom of the container
Water filtered through sand/membrane
To kill any further pathogens (like the ones that cause Cholera and typhoid), chlorine is added
What is a bore?
Full water is ground water that has been accessed by drilling into underground water stores called aquifers
A pump is typically required to bring water to the surface
How have governments across the world been tackling pollution?
Legislation
is stormwater the same as waste water?
no
where are sources of domestic water?
Toilet, showers, washing machines, etc
Is domestic waste water treated before going back into the environment?
In most countries, yes
Why is domestic waste water bad?
can cause diseases such as cholera
what is industrial waste water?
Waste water that could be contaminated from factories with detergent, Metals from manufacturing, can include gases.
Can also include waste water that is untreated being sent out into the environment
what are examples of some heavy metals industrial wastewater can carry into the environment?
Mercury, copper, lead, manganese
why is industrial waste water bad?
can cause bioaccumulation, biomagnification, dieback and acid rain
What is agricultural waste water?
waste water with an excess of nutrients such as phosphorus and nitrogen from things such as inorganic fertilisers chemical pesticides
