OEI Chemistry
1.
Describe a local catchment area: include maps and a full description of
the sources of water and potential sites for pollution.
Warragamba catchment area is the main local catchment area providing
water to Sydney. It is located 65 kilometres west of Sydney and covers an
area of 9,050 square kilometres. The sources of water of the dam and
catchment include the Wollondilly, Wingecarribee and Cox River systems,
joining together to form Lake Burragorang, and the dam itself.
The Wollondilly catchment area, under the control of Wollondilly Shire,
east of Taralga, consists of smaller catchments, including the Tarlo River
and Paddys River. The care of quality is under the Sydney Catchment
Authority.
The Wingecarribee catchment area, is another sub-catchment of the
Warragamba Dam Catchment. The Wingecarribee River is a relatively
large and long water system, flowing into the Wollondilly before going
into Lake Burragorang, and the dam.
The Cox River Systems, also a sub-catchment of Warragamba, located
west of Katoomba. The area consists of many smaller rivers and creeks in
the catchment area, including the Ganbenang Creek, Little Creek and
Jenolan Rivers.
Potential Sites for Pollution:
More than half the Warragamba catchment area consists of native
vegetation. However, there is also a large amount of land used for
agriculture, infrastructure (roads) and living/urban areas - these are the
possible sites of pollution.
Agricultural Areas: Areas that are involved in intense and extensive
farming is a potential source of contamination. Pesticides and herbicides
may contain metal ions (including copper) which can be washed into the
catchment. Fertilisers used may also include phosphate ions and nitrogen.
The presence of phosphate and nitrogen can increase the chances of algal
blooms in the water system as it increases the nutrient level, lowering the
water quality (for consumers because of the micro-organisms) and
increasing the microbial presence. Copper is a water contaminant and if
consumed in excess for extended periods may cause kidney and liver
damage. Concerning the agriculture of animals, their faeces may enter the
water system, bringing with it various micro-organisms including E. coli,
which may cause gastroenteritis and urinary tract infections. Their faeces
would also contain phosphate ions which would again lead to increase
chance of algal blooms.
Industry & Land Clearing: Sites of developments, for new housings,
industry or agriculture present the risk of increasing the turbidity of water.
This area would be prone to erosion and the sediments would be easily
mobile, allowing rain to wash it down into the catchment areas to
increase the turbidity (cloudiness). Clearing land for mines would have the
same effect. With the factories within the area used in industry, the
wastewater may contain metal ions causing metal pollution. These can
range from transition metal ions to heavy metal ions, causing the
decreased water quality and pollution.
Mines:
Mine pose a threat to water catchment areas. Waste rocks, along with
sediments formed through erosion from mining can be washed into the
waterways. This would increase the turbidity of the water, decreasing the
water quality. There is also the chance that metal pollution/ion pollution
may occur for the catchment from the minerals that are being mined or
others in the site. These metals may enter the water system, thus causing
the pollution.
Storm Water and Roads:
Storm run-offs of urban areas would bring about litter and chemicals that
may be present on footpaths and roads. This would enter the water
system, decreasing the quality of the water in the catchment. It would
increase turbidity.
Urban Sewage Plants:
Sewage plants in urban areas may overspill in floods and therefore cause
contamination from faecal coliforms into the water system. There is also
the potential for the sewage to not be properly clean, thus leaving the
coliforms to be in the treated water. Once this treated water is released, it
may contaminate water ways and the catchment.
2.
Describe THE TESTS for any factors that need to be monitored in the
catchment to ensure that we have safe drinking water.
There are many things that should be monitored to ensure that the water
is safe to drink. These include the presence of ions, the total dissolved
solids present, the water's hardness, turbidity, the pH, the presence of
faecal coliforms, and the dissolved oxygen in the water.
Presence of Ions & Hardness (Various Tests Used):
The presence of some ions in water may be an indicator of unsafe quality
of drinking water. High levels of phosphate ions and nitrogen in water
make the system highly susceptible to eutrophication, or algal blooms.
These ions must be monitored in order to decrease the chances of this
happening, ensuring that our water is not contaminated with the
organisms, which produce toxins. These toxins, once consumed may cause
stomach pains, diarrhoea and fevers. Some other ions must also be
monitored in water. These include the presence of heavy metal ions. Lead,
mercury and cadmium that bio-accumulate and bio-concentrate,
interfering with the biological processes of organisms and is very
dangerous in high amounts in the body. These heavy metals may cause
permanent brain damage if accumulated enough in our bodies. Water
hardness, although it does not affect us majorly concerning health, affects
the productivity of water use, preventing lather. The ions that contribute
to this are calcium ions and magnesium ions. The tests to detect these
ions include AAS (Atomic Absorption Spectroscopy), which works through
the exploitation of the characteristic that different elements absorb
different light spectrums. The sample is vaporised and passed with a
beam of light, from a light bulb containing the element to be tested. A
monochromator would then be used to diffract the light, passing it
through to a photomultiplier. The results can then be interpreted from a
display. This method is extremely accurate to pinpoint the amount of the
element present in the water sample, however, it cannot be used to
measure the amount of molecules (e.g. phosphates). Other tests include
using an Ion Selective Electrode (ISE), which are galvanic half cells that
measure the potential difference related with ion or dissolved gas
concentrations. Both AAS and ISE need to be calibrated using a known
sample of the substances being tested and put into a graph before
accurate measurements can be done. The tests of ions can also be done
using a precipitation test. Chemicals are added to the sample, testing for
the presence of a specific ion. If the ion is present a precipitation and/or
colour change will be observed. Hardness may also be measured using a
volumetric titration with EDTA (ethyenediaminetetraacetic acid), and the
water sample, and then the calcium ions can be calculated.
Total Dissolved Solids (Logger and Gravimetric Analysis Tests):
Total dissolved solids are a factor that influences safe drinking water
which overlap with the ions (mentioned above). Total dissolved solids are
a generalisation of all the ions that are present in the water. It hints to the
potential hazard that the water has. The total dissolved solids can be
determined through a gravimetric analysis. First, the water is filtered. The
filtrate's mass must then be determined and then evaporated. The residue
from evaporation is the total dissolved solids. This can also be done using
a data logger with an electricity probe attached, as total dissolved solids
are ionic substances and they conduct electricity. The logger will
automatically produce a figure/result once inserted to a sample.
Turbidity & Colliforms (Secchi Disks & Nephelometor Test) :
Turbidity and the level of dissolved oxygen in the water have a
relationship that affects one another. Turbidity is the measure of the
cloudiness of the water - how much sediments and particles are in the
water. Dissolved oxygen refers to the amount of oxygen available in the
water. Turbid water may contain toxic substances but also including
pathogens like faecal coliforms and E.col (Escherichia coli). E. coli is also
used as a measurement for the suggest how much microbial life is in the
water. The higher the turbidity, the more chances are that there are these
pathogens. Pathogens like E. coli, if consumed may cause stomach pains
and diarrhoea as examples of the symptoms. This is why turbidity must be
tested in water. Turbidity is measured through the use of secchi disks, a
tool which is lowered into the water. The turbidity is measured by the
length it takes for the disc to disappear from view. A nephelometor may
also be used. It is a machine which shines light through the turbid water to
a detector. This detector then calculates the turbidity of the water.
Turbidity is measured in nephelometric turbidity units (NTU).
pH (Indicators and Logger Tests):
pH or potential of hydrogen, measures the acidity or alkalinity of a
substance. Universal Indicator may be used to detect the pH. The
indicator is added to a sample of water, and with a colour chart (for the
indicator), the pH can be determined. A data logger with a pH probe may
be also be used to obtain an even more accurate measurement of pH.
Water should be approximately 6.5~8.5 in pH, above or lower would
interfere with our enzymes and the efficiency of our metabolism (a little
below 7 is considered relatively normal also as there should be carbon
dioxide released by aquatic organisms). As enzymes work in a narrow pH
range, otherwise they denature, we need to carefully monitor the pH to
not allow it to go too high or low for safety issues as this is consumable
water.
Ion Test (Flame Test):
Using the characteristic that different metal ions produce different colours
when their salts are volatilised in a blue flame on a Bunsen Burner, we are
able to determine what substances (metal ions) they are. This works
because when a metal salt is vaporised in a flame, the electrons on the
metal's outer shell goes into an "excited" state and jump to another shell.
As this happens, they absorb a specific wavelength of the light spectrum,
and once the electrons move back to their original place (as the excited
state is unstable), they emit light of the frequency they absorbed. Every
element has a different specific frequency that they emit allowing us to
differentiation between them. This can be used to test the ions in the
water sample, to see if there are any unwanted metal ions within the
substance.
Dissolved Oxygen (DO, variety of tests):
Dissolved oxygen levels, although not strictly necessary for human beings
in drinking water, hints to the health of the water system. The lower the
DO level, the more unhealthy the water can be seen, and less suitable it is
as our drinking water - as if there are algal blooms and other microorganisms, they would use up most oxygen). There are a few methods to
measure the oxygen levels of a water system. One is using the
potentiometric oxygen probe. It is an instrument using thallium oxygensensitive electrode connected to a reference electrode as part of a
galvanic cell, and if there is oxygen present in the tested water sample,
electric would be conducted. This would then tell us the level of DO. This
must be calibrated with known samples first. Another is using the
Wrinkler Method. This method is based off a series of chemical reactions.
In the method, oxygen is eventually combined with iodine to form a
yellow chemical. Each molecule of dissolved oxygen is associated or
attached to one iodine, and thus we can measure the oxygen by using
sodium thiosulfate and occasionally starch as an indicator.
Biochemical Oxygen Demand:
Biochemical oxygen demand is an assessment of the capacity of organic
matter that may survive or use the oxygen in the water. Biochemical
oxygen demands suggests how much bacterial or microbial life is in the
water sample and hints to the quality of the water. It is a way of
measuring organic pollution. The biochemical oxygen demand of a sample
can be tested by the standard 5 day test, measuring the levels of dissolved
oxygen (using an oxygen probe) 5 days apart from each other. A second
sample is stored in the dark at 20oC, in a closed incubation bottle, as a
type of control, to disallow photosynthesis if there are photosynthetic
microbial life present. The difference in dissolved oxygen levels after 5
days is the biochemical oxygen demand.
Nitrate Test (Brown Ring Test)
Testing for nitrates in water catchment samples is necessary to determine
the nutrient level of the water. This is done to determine the susceptibility
of the water system to eutrophication and algal blooms, which affect the
quality of drinking water. Iron (II) sulphate is added to the water sample
and concentrated sulphuric acid is added to form a separate layer. If there
is a presence of a brown ring (Fe(NO)SO4) at the border between the two
liquids, it indicates that it is positive and that there is indeed nitrates in
the sample. Through calculations, an approximation of the levels of
nitrates present in the water can be determined.
Phosphate Test (Using Visible Spectrometry)
A reagent is added to a sample that forms a coloured complex if
phosphate ion is present within the sample. The intensity of the colour
change is then measured by a spectrophotometer and the concentration
can be determined by using a calibration curve to compare the
absorbance of light by the coloured solution to those that are known and
recorded in the curve. A phosphate test indicates the level of nutrition
available in a water sample. It hints to the susceptibility of algal blooms
and low quality water
Precipitation Tests (for Cations and Anions)
Apart from AAS and other tests mentioned above, precipitation tests may
be conducted to determine the ions (cations and anions) present in the
water sample. As some ions are toxic to humans in large quantities in
drinking water, and may cause stomach upset, this must be monitored.
Below is a table from Jacaranda Chemistry 2 by Geoffrey Thickett,
outlining the precipitation tests available.
Anions:
Cations:
3. List typical water-quality data for a healthy catchment
These are the site specific standards of Warragamba quality test results
and compared to the ADWG (Australian Drinking Water Guideline) as of
2011-2012 (2012-2013 not yet released) from their annual report.
Note: Those with asterisks are data from 2005 and present data of water
with added fluorine and treatment stated by Chemistry Context 2 by
Debbie Irwin, Ross Farrelly, Deborah Vitlin and Patrick Garnett. Those
without are raw data obtained from the Sydney Catchment Authority, and
represent the data of untreated water. Those with # are from Namoi
Catchment Authority, and their data of a healthy catchment - this is
separate from Warragamba and is a generalisation of catchment quality.
ADWG Criteria
Warragamba
Good
Quality
Catchment
for
freshwater
#
E. Coli * (% in water)
98% of water
must contain no
E. coli
0
n/a
Total Coliforms* (% in
water)
95% must contain 0
no coliforms
n/a
Fluoride* (% complied)
95% of water
must have 0.9 to
1.5 mg/L
100
n/a
Chlorine* (% complied) 95% of water
must have less
than 5 mg/L
100
n/a
Trihalomethane* (%
complied)
95% of water
must have less
than 0.25 mg/L
100
n/a
Turbidity* (NTU)
Average < 5 NTU
0.12
n/a
True Colour* (HU)
Average < 15 HU
<2
n/a
Iron* (mg/L)
Average < 0.3
mg/L
0.012
n/a
Turbidity (NTU)
N/A as not
drinking water
40
n/a
True Colour (CU)
N/A as not
drinking water
60
n/a
Iron (mg/L)
N/A as not
drinking water
3.50
n/a
Manganese (mg/L)
N/A as not
drinking water
1.40
n/a
Aluminium (mg/L)
N/A as not
drinking water
2.60
n/a
Hardness (mg/L as
CaCO3)
N/A as not
drinking water
25.0-70.0
n/a
Alkalinity (mg/L as
CaCO3)
N/A as not
drinking water
15-60
n/a
pH
N/A as not
drinking water
6.3-7.9
n/a
Temp (In Degrees
Celcius)
N/A as not
drinking water
10.0-25.0
n/a
Algae (ASU)
N/A as not
drinking water
2000
n/a
Faecal Coliforms # (per
100 mL)
n/a
n/a
0
Total Dissolved Solids # n/a
(mg/L)
n/a
100-1000
Turbidity # (NTU)
n/a
n/a
<10
Dissolved Oxygen #
(DO % trigger value
range)
n/a
n/a
60-120
Phosphates # (mg/L)
n/a
n/a
<0.06~0.15
4. Identify the potential types of contamination that may come from EACH
area of the catchment:
Factory:
The possibility of contamination via metal ions is very possible due to the
industry processes that may be used in the industry. Calcium and/or
magnesium along with heavy metal ions may be released from the factory
as effluents which in turn can contaminate the water catchment. This
would not only lead to poor water quality but also pose major health risks
due to the heavy metals present that may bioaccumulate and
bioconcentrate. The calcium and magnesium ions would also make the
water hard, which would have the effect of negating the water's ability to
lather with soap. If this is a herbicide or pesticide factory, toxic chemicals
to aquatic life may also end in the water ways, disrupting their
biochemical functions and may lead to their death. The chimneys of
factories may also pose a risk for acid rain if oxides of sulphur and
nitrogen are released (or slightly more acidic rain if carbon dioxide is
released). This can then cause the lowering of pH in the water catchment
area, again disturbing the biochemical processes of marine life, and may
eventually kill them.
Tidal Rivers that flow into the Ocean:
There is a high possibility of contamination via salts in this area. The river
joining to the ocean may have a high salinity level, therefore the
concentration of sodium and chloride ions may be high. Although they do
not pose much of a risk normally, if there are more than 20mg/L of
sodium in drinking water, it may pose health risks to those with kidney
problems or heart problems. There also may be sulphate ions present. If
sulphate levels are too high, there is the potential for diarrhoea in
consumers (stated by the USEPA government website). There is the
potential for waste contamination in the river due to aquatic life. Their
excretion would contain faecal coliforms like E. Coli which in large
amounts if consumed, is harmful to humans. Their faeces would contain
nutrients, thus making the water system susceptible to algal blooms, and
thus decreasing the water quality also. There is also the possibility of litter
pollution from the banks of the river. This would increase the turbidity,
while also interfering with aquatic life.
In Proximity to the City:
The fact that the catchment area is in proximity to an urban setting makes
it prone to contamination with acids and alkalis or any other runoffs due
to storm water. Hydrogen or hydroxide ions can contaminate the water
supplies affecting the pH outside the healthy range of 6.5-8.5 . If the water
is too acidic, pipe corrosion in pipes may occur and if too alkaline, it would
produce scaling in pipes. Storm water may also carry sediments and litter
into the catchment, increasing the turbidity of the water as well as
washing down faecal coliforms that may be present in domestic animal
faeces. There is also the prospect of sewage contamination from the
treatment plants located in the city. There is the possibility that the
herbicides and pesticides used in urban settings, may also be washed into
the catchment via the stormwater. This would allow toxic chemicals to
reach the catchment, chemically contaminating it.
Forested Areas:
The forested area pose mostly a pathogenic pollutant to the water. As
animals in the habitat drop their faeces in the area, rain or storm water
may wash them down into the catchment area. This brings E. coli and
other pathogens into the water system, contaminating the water. Along
with these micro-organisms that enter the system, there is also the
chance of contamination via phosphorous and nitrogen from the soil. The
nutrients which run off into the water would increase the nutrition
content and make the system prone to eutrophication and algal blooms,
posing a risk to other aquatic life by using the dissolved oxygen in the
water. If these algae were to survive the screening for drinking water,
they can pose health risks to individuals as well. Sediments from the
forested area may also increase the turbidity of the water once the water
is run off by rain or storm water - sediment/turbidity contamination. As
this is a forested area, leaf litter (containing nitrates from plant life), which
should contain nutrients, may enter the water system, thus increasing the
nutrient available in the water. This would increase the susceptibility if the
catchment to algal blooms, decreasing the quality.
5. Explain the impact of two specific factors from each of the four area of
the catchment.
Factory:
o
Chemicals: chemicals which are used in the industrial process of the
factory may run off into the catchment. These chemicals may include
heavy metals (lead, cadmiun, arsenic and mercury) which may have
major impacts to the environment and to us who may consume the
water after filtration processes. These heavy metals bio-accumulate
and bio-concentrate, meaning that they concentrate in the organism
and is transferred into the organisms that eat them, thus moving up
the food chain. If concentrated enough in the body, it may interfere
with biochemical processes, thus killing aquatic life and those that
consume it.
o
Waste Material & Gaseous Releases: Waste Material from industrial
processes can increase the turbidity of water when they enter the
water system. The impacts of increased turbidity include negating the
photosynthetic processes of aquatic plants, resulting in their death.
This affects the aquatic food chain and kills other aquatic life, e.g.
fish. The factory may also release gases, including carbon dioxide,
oxides of sulphur and nitrogen from their industrial processes. This
gives way to acid rain in the area, thus making the catchment
susceptible to a decrease in pH. This may affect the biochemical
processes of aquatic life, including enzymes which may lead to the
death of the organisms.
Tidal River Connected to Ocean:
o
Litter on Banks of River: There is the possibility that the river banks
are polluted with litter. The litter would not only decrease water
quality and increase the turbidity of the system, but also interfere
with marine/aquatic life. They may find small litter to look like food,
thus consuming the litter. This is a choking hazard towards these
organisms, negating their ability to respire and, thus killing them. The
polluted catchment water must also undergo much filtering
processes as well as cleaning to ensure it is safe for drinking.
o
Aquatic Life Excess: The faeces excreted by aquatic life would contain
hazardous microorganisms including E. coli, which in large quantities,
and consumed, can negatively affect the consumer's health. This
decreases the quality of the water. The water from this catchment,
would therefore, need to be extensively cleaned to reduce the
numbers of pathogens in the water, allowing the water to be potable.
City:
o
Storm Water: Storm water may bring debris and other substances
into the catchment area. The substances the storm water may bring
include chemicals and faecal coliforms from domestic animal faeces.
Once washed into river systems, these chemicals may change the pH
of the water, affecting biochemical processes of aquatic life and their
metabolism, and may result in their death. Faecal coliforms, like E.
coli and cryptosporidium would decrease the water quality, and
therefore, extensive processes for the cleaning of the water must be
done before it is safe for human consumption when this catchment's
water is used to produce drinking water. The debris washed by the
storm water may also increase the turbidity of water, leading to the
negation of the photosynthetic processes of aquatic plants, killing
them and affecting the aquatic food chain.
o
Sewage Treatment Plants: Sewage treatment plants are usually
within the vicinity of urban settings. These pose threats of pathogenic
contamination to the water catchment. If there is a leak, or if the
sewage is not cleaned properly, before being released back into a
water system, then faecal coliforms may enter the system. The
impacts of these coliforms (E. coli, cryptosporidium and giardia) are
that they decrease water quality and would negate the water from
being consumable unless treated extensively.
Forested Area:
o
Animal Faeces: Animals which live in the forest habitat's faeces may
enter the water system by being washed down by rain. This would
increase the faecal coliforms present in the water system. Faecal
coliforms, such as E. coli pose health risks to humans if drunk. There
is also the possibility that other microorganisms are washed down
from the forested area, including giardia and cryptosporidium, which
are pathogens, causing illnesses in the intestines in human bodies.
The water catchment, therefore must be properly treated before
being potable - this is the impact.
o
Nutrition and Sediments: Nutrients from the soil like phosphates and
nitrates (phosphorous or nitrogen compounds) may run off into the
water system. This could increase the amount of nutrition available in
the water and cause or speed up eutrophication of the water system.
Algae growth would result, depleting the levels of dissolved oxygen in
the water, thus killing other aquatic life due to the inability to respire.
A result of this is decreased water quality, increasing the workload of
the cleaning process for the water of the catchment to be drinkable
and at a safe standard.
6. Outline a treatment plan for the water for two areas of the catchment.
Explain the physical and/or chemical principles involved in this water
treatment.
Urban Area: Stormwater from urban areas pick up litter and other
pollutants left on the ground including grease, oil, bacteria and other
chemicals. A treatment to improve the quality of storm water and thus of
the water that enters the catchment is to install Stormwater Quality
Improvement Devices (SQIDS) in large storm water drains. These SQIDS
work like filters and trap big particles and litter to increase the quality of
the water that gets through. This works through the use of physical
properties, that is the difference in size, physical and molecular, of water
compared to the litter, thus separating the two substances. Sewage from
urban areas must also be cleaned before entering the water system and
must be treated to prevent pollution. Sewage undergoes three main
processes. The first is screening or filtering, whereby the physical property
of size and weight is used to separate the water from other matter such as
tissue, sand, oil and human waste. The nutrients that may be left in the
water are then removed by bacteria in a separate tank - exploiting the
biochemical processes of bacteria, before being disinfected by chlorine or
ultra violet light. Disinfecting reduces the chances of microbes and
pathogens being released into the water system, by using the disinfectant
chemical properties of chlorine and the harmful chemical property of UV
rays.
Factory: Factories is a considerable threat to the water system and the
catchment. Factories which use heavy metals can contaminate the water
system. As a treatment, factories may undergo a dilution process with
their wastewater in order to bring the concentration down to the level
that is recommended by the Australian government - which is less than or
equal to 0.01mg per litre of water (according to the Australian Drinking
Water Guidelines set by the Government of Australia). Dilution is a
physical change using the properties of water. Some factories may also
undergo desalination of their chemicals if the salt level is too high. This is
not common as desalination is an expensive process. Through the process
of reverse osmosis this is possible. This, again is a physical change.
Gaseous releases of the factories may be counteracted using chemical
processes including using chemical scrubs. Monoethanolamine (MEA) is
used to scrub carbon dioxide from gas streams. If the factory has a
problem with excess carbon dioxide emission, which may decrease the pH
of local rain, then this is a treatment to prevent the carbon dioxide from
escaping into the atmosphere, thus negating the increase of weak acid
rain (by carbon dioxide) to enter the water system.
7. Describe the monitoring process necessary for all sites and include
chemical equation where appropriate
Factory: Monitoring of the wastewater that comes out of the factory is
necessary for this site. The water released from the system must be tested
with ion testing and heavy metal testing to ensure that the water released
which may enter the catchment is safe and up to the Australian
Government's standards. After the dilution, if that is a treatment the
factory would use, the concentrations of the substances must then again
be checked.
Tidal Rivers: Humans would have to monitor the amount of microorganism activity as well as the concentrations of metals and other ions in
the water. These substances may polute the environment as well as
contaminate the catchment water. Monitoring of chemical substances in
the water is also necessary to ensure that the water to be used as drinking
water is of a safe standard
Urban: Wastewater plants must be monitored as they are a potential site
to contaminate the water through the faecal coliforms. The water must be
tested for these microorganisms, as well as the pH, before releasing it into
the water system. A failure to do so may result in the interference of
biological processes of aquatic life.
Forest: The site must be regularly checked to see if there are any sources
of pollution at the site, including…………?
8. Identify the organisation that monitors the waterways of NSW and
describe the types of chemistry that is used in the monitoring process.
The Sydney Catchment Authority, established in 1999 under the Sydney
Water Catchment Management Act of 1999, is the main body responsible
for the monitoring of the waterways of NSW and ensuring that the water
supplied to be used for drinking water is of appropriate standards and
quality. In this process of monitoring, different types of chemistry are
used together to test and ensure that standards are met. The process of
sampling of the waterways, testing reactions for a positive or negative for
the quantity of pollutants give way to the use of analytical chemistry,
which involves the study to identify specific chemicals and thus,
pollutants. This type of chemistry can be applied to quantitatively as well
as qualitatively analyse (using wet or instrumental methods) samples of
the waters taken - which is especially needed in times of flooding and
overflow, as the turbidity, along with other factors including the
concentration of metal ions may increase. Another type of chemistry
which is used in the field is the organic chemistry. The knowledge of the
organic chemistry field includes the ability to recognise organic substances
- molecular structure containing carbon or carbon based molecules, which
can be applied to identify these substances in the water system as
contaminants. An example is to monitor the amount of synthetic organics
in the water body - e.g. pesticides used including amitrole (an organic
herbicide) These two types of chemistry, analytical and organic, are
therefore useful for monitoring the amount of pollutant substances in the
waterways.
9. Choose one named branch of chemistry for a more detailed study and
explain the chemical principle involved in the work as well as the role
that such a chemist would play in water quality evaluation
Analytical chemists play a role majorly, in the evaluation of water quality.
Analytical Chemists are those who have graduated from a Science or
Applied science degree majoring in chemistry. The role of the analytical
chemist is to identify unknown material while also accurately measure the
amount of a particular chemical in a sample. They have the ability to
specialise in environment and pollution control. Because of this
specialisation, they are very useful asset in the monitoring of water
quality. They are able to determine what substances are in the water,
including the ions and heavy metals - using precipitation tests and others
using wet or instrumental methods to do so - and other chemical
pollutants such as chemical compounds used in farming. The ability to
detect and test these substances, therefore allow them to be able to
evaluate the quality of the water, and thus if it is at an acceptable
standard or not.
10.Explain the need for collaboration between chemists as they collect and
analyse data for water quality
It is important as some would have particular expertise and abilities
others would not have and this can be applied in monitoring water
quality. An example is the collaboration between an analytical chemist
and an organic chemist water quality testing. The analytical chemist would
specialise with the identification of chemicals and their compounds - using
their tests, either with instruments or traditional wet methods - which can
be specifically applied on water samples. Many analytical chemists may
also work together, thus decreasing individual work load and speed the
process of identification and development of a treatment. With the help
of organic chemists, however, the knowledge on the compound/element
analysed can be expanded upon. For the organic chemist, they may
establish the use of the carbon based compounds that may have been
identified, and further build on the knowledge of the analytical chemists,
as they specialise in those areas. This may become very useful with the
knowledge they may have on organic pesticides and herbicides that may
be used in farmland which end up in the river and thus the catchment
area - which can include Amitrole, Atrazine and Chlorpyrifos (types of
organic pesticides/herbicides) - and may have knowledge of the treatment
of these organic compounds. The information from the two combined
different chemists allows the development for a treatment and/or
monitoring plan to achieve an acceptable water quality. From this
example, using it in the context of water quality, we can see that the
collaboration is a need and is important between chemists.
11.Include a Bibliography and state why the sources are reliable and valid.
1.
2.
3.
4.
5.
Sydney Catchment Authority, 2012, Penrith NSW, viewed 11/05/2013
http://www.sca.nsw.gov.au/dams-and-water/major-sca-dams/warragamba-dam
http://www.sca.nsw.gov.au/__data/assets/pdf_file/0003/4863/Warragamba-dambrochure-Nov-2010.pdf
http://www.hn.cma.nsw.gov.au/topics/2071.html
http://www.hn.cma.nsw.gov.au/topics/2048.html
http://hsc.sca.nsw.gov.au/chemistry/water_contamination/possible_sources/land_use
6.
http://npic.orst.edu/ingred/ptype/treatwood/copper.html
7.
http://npic.orst.edu/ingred/active.html
8.
http://water.epa.gov/drink/contaminants/basicinformation/copper.cfm
9.
http://www.who.int/water_sanitation_health/diseases/cyanobacteria/en/
10.
11.
http://www.fi.edu/learn/brain/metals.html
http://water.epa.gov/drink/contaminants/unregulated/sulfate.cfm
12
13.
14.
http://www.public.health.wa.gov.au/cproot/4188/2/SodiumInDrinkingWater.pdf.
http://www.sydneywater.com.au/SW/teachers-students/facts-about-water/secondarystudents/where-does-water-go-/wastewater/index.htm
http://www.sydneywater.com.au/SW/teachers-students/facts-about-water/secondarystudents/where-does-water-go-/stormwater/index.htm
15.
http://www.uwlax.edu/chemistry/html/types.htm
16.
http://www.oxfordreference.com/view/10.1093/oi/authority.20110803095531586
17.
http://serc.carleton.edu/microbelife/research_methods/environ_sampling/oxygen.html
18.
http://www.namoi.cma.nsw.gov.au/factsheet_water_quality_parameters.pdf
19.
20.
http://antoine.frostburg.edu/chem/senese/101/environmental/faq/co2-recycling.shtml
http://www.nhmrc.gov.au/guidelines/publications/eh52