DEPARTMENT OF BIOLOGYFACULTY OF SCIENCE & TECHNOLOGYUNIVERSITI PENDIDIKAN SULTAN IDRIS

TSE 2013

Environmental Science

ACTIVITY REPORT:

STUDENT’S NAME

Nur Ashikin binti Ahmad Termizi(Leader) D20061026254

Nurul Akma binti Bahari(Secretary) D20061026262

Noor Diana Salmie binti Ahmad D20061026257

Siti Rusilawati binti Tomin D20061026263

Siti Nurbalqis binti Mohd. Hanafi D20061026283

LECTURER’S NAME PROF. DR SUPLI EFFENDI RAHIM

DEMONSTRATOR’S NAME PROF. DR SUPLI EFFENDI RAHIM

EXPERIMENT NO. / TITLE

1A: Water and Wastewater Analysis (Physical and Chemical Parameters1B: Water and Wastewater Analysis (Biological Parameters)

DATE/DAY/TIME January 19, 2009 / Monday / 8.00 p.m. – 11.00 p.m

LABORATORY Laboratory 3c

SEMESTER IISESSION 2008/2009

TITLE:EXPERIMENT 1A:

Water and Wastewater Analysis (Physical and Chemical Parameters)

INTRODUCTION:Water has many properties. One of its properties is its ability to dissolve many

substances. Because of this property, water is known as the universal solvent and is

seldom found pure in nature. In fact, natural waters may contain hundreds or even

thousands of chemicals, and in some cases, an equal number of biological life forms

(such as microorganisms). All forms of life depend on water. Water helps to dissolve

chemicals in foods, and then it transports these chemicals to cells in our bodies.

However, sometimes harmful substances can dissolve in water. Substances that harm

the quality of water are known as pollutants or contaminants. Most contaminants in

water do not cause problems because they are not toxic and are at such low amounts.

However, some substances which dissolve in water, even at very low levels, can be

harmful.

There are two primary causes of water pollution: nature and people. Actually,

although pollutants and contaminants are generally used to mean the same thing,

pollutants are usually thought of as contaminants or impurities in water due to the

activities of people. Contaminants are usually thought of as impurities in water

caused by natural processes. Naturally occurring events such as volcanic eruptions,

landslides, floods and wild animal wastes, can produce polluting materials. These

pollutants can wash into lakes, rivers and other streams and damage water quality.

People contribute to water pollution in their homes. In fact, homeowners apply

more fertilizers and pesticides, per square foot, on their lawns and gardens than

farmers apply to entire crop fields. Homeowners don't always properly dispose of

poisonous wastes, either. Some wastes may be thrown into ditches or the woods, or

flushed down the drain. Even some of the wastes that end up in landfills may leach

into water supplies. Septic systems that are not functioning properly also can

contaminate groundwater. All of these things can contribute to water pollution.

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OBJECTIVES:After conducting this experiment we should be able to:

1. Compare several differences between polluted and unpolluted stream.

2. Learn the technique for evaluating water quality in term of physical and

chemical parameters.

METHODOLOGY:

I. Physical Parameters

A. Temperature

1. Thermometer is used to take a temperature reading of a stream.

2. The reading had been taken on site in a free-flowing portion of the

stream. In some situation, the thermometer needs to be attached to a

pole or wade into the stream.

3. Result is recorded.

Thermometer

B. pH

1. In this experiment, the pH of water is measured using a portable pH

meter. The measurement is taken in a free flowing portion of the

stream. pH measurement is accomplished by using pH meter.

2. The meter is on.

3. Probe is put in first calibrating buffer.

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4. CAL is pressed to calibrate for two pH solution: pH 7.00. Then, button

ENTER is pressed.

5. Probe is rinsed by using distilled water.

6. Next stored is buffered with pH 4.01 and ENTER button is pressed.

7. Probe is rinsed by using distilled water again and being place in

sample. Reading is taken.

pH meter

C. Turbidity

1. The meter is calibrated by using 4 calibration solutions as provided

with the meter.

2. The water sample is mixed thoroughly.

3. Clean sample vial is prepared.

4. The vial is rinsed with the sample solution.

5. The rinsed vial is filled (approximately 10ml).

6. The vial is wiped with soft cloth.

7. A thin film of silicon oil is applied.

8. The vial is placed into the meter for measurement.

9. The vial’s mark is aligned with the meter’s mark.

10. The vial is covered with the light shield cap.

11. The meter is tuned on.

12. Reading is taken.

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Turbidity meter

D. Total Suspended Solid (TSS)

Preparation of filter

1. A filter disk is placed in filtration assembly with rough (wrinkled side up)

2. A vacuum is applied and filter disk is rinsed with three separate 20mL

portions of distilled water. Vacuum is discontinued when all the traces of

water have been removed.

3. Rinse filtrate is discarded from filter flask.

4. Filter is dried assembly in an oven at 103-105ºC for 1 hour.

5. Filter is cooled in desiccator to room temperature.

6. Filter and support is weighed.

7. Steps 4-6 are repeated until a constant weight is achieved.

8. Prepared filter and support is stored immediately before use and its weight

is recorded.

Sample filtration and weighing

1. Filtration apparatus is placed with weighed filter in filter flask.

2. Sample is mixed well and is poured into graduated cylinder of 100mL

volume.

3. Suction is applied to filter flask and filter is sealed with small amount of

distilled water.

4. Selected volume of sample is poured into filtration apparatus.

5. Sample is drawn through filter into filter flask.

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6. Graduated cylinder is rinsed into filtration with three successive 10mL

portion of distilled water, allowing completed drainage between each

rinsing.

7. Suction is continued for three minutes after filtration of final rinse is

completed.

8. Filter is dried in an oven at 103-105ºC for at least 1 hour.

9. Filter is cooled in desiccator to room temperature.

10. When cool, filter and support is weighed.

11. Steps 8-10 are repeated until the weight loss is less than 0.5mg or 4% of

the previous weight.

12. Total suspended solid (mg/L) =

Weight of the filter, support and dried sample – Weight of the filter and

support before sample is filtered × 1000 mg

Size of sample filtered (in mL) × 1L /1000 mL

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II. Chemical Parameters

A. Dissolved Oxygen

1. DO is calibrated using the following instructions given by the

manufacturer.

2. Water sample is collected to 500 mL.

3. Bottle is allowed to overflow at least 2 minutes. Bubbles are not

allowed.

4. DO is placed in the sample, the meter is allowed to equilibrate and DO

is read directly.

5. Last three readings are taken.

Dissolve Oxygen meter

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RESULT:

I. Physical Parameters

A. Temperatures

Solution Temperature

X (waste water) 22.3 ºC

Y (stream water) 22.9 ºC

B. pH

Solution pH value

X (waste water) 8.44

Y (stream water) 8.28

Distilled water 8.22

C. Turbidity

Sample Water Reading (NTU)

X (waste water) 8.88 NTU

Y (stream water) 8.41 NTU

D. Total Suspended Solid

Sample size: 50mL

Sample X (waste) Y (stream)

Weight of the filter and support

before sample is filtered (g)0.6410 0.6487

Weight of the filter, support and

dried sample (g)0.6571 0.6603

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II. Chemical Parameters

A. Dissolved Oxygen

X (Waste Water) Y (Stream Water)

6.46 5.84

6.55 5.89

6.53 5.98

Average = 6.51 Average = 5.90

CALCULATION:

1) Total Suspended Solid (TSS)

Sample X:

TSS = (0.6571-0.6410) × 1000 mg

50 mL × 1L /1000 mL

= 322 mg/L

Sample Y:

TSS = (0.6603-0.6487) × 1000 mg

50 mL × 1L /1000 mL

= 232 mg/L

DISCUSSION:

I. Physical Parameters

A. Temperature

Based on our observation, the temperature obtained for X solution (waste

water) is 22.3 ºC while the temperature for Y solution (stream water) is 22.9

ºC. From the result obtained, we may conclude that both of the water has

temperature above 20 ºC which can be described as warm water.

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Temperature (ºC) Examples of life

Greater than 20ºC (warm water) Much plant life, many fish diseases.

Most bass, crappie, bluegill, crap, catfish,

caddis fly.

Middle range (12-20 ºC) Some plant life, some fish diseases.

Salmon, trout, stone fly, mayfly, caddis

fly, water beetles.

Low range (cold-less than 12 ºC) Trout, caddis fly, stone fly, mayfly.

Temperature influences the amount of dissolved oxygen in water

which in turn influences the survival of aquatic organisms. When temperature

is increased, the dissolved oxygen saturation level will be decreased thus

increasing the rate of chemical reactions that takes place in the water. The

result shown that stream water has slightly high temperature compared to

waste water thus we may predict that stream water has lower dissolved oxygen

saturation level.

B. pH

pH indicator is used to measure the acidity and alkalinity of water. Normally,

the pH of natural water is in the range of 6.5 to 8.5. The result obtained from

this experiment shown that X solution (waster water) has pH of 8.44; Y

solution has pH of 8.28 while distilled water has pH of 8.22. It could be seen

clearly that distilled water has slightly low pH compared to other solution.

Typically, natural water has pH 6.5-8.5 because most aquatic cannot

survive in pH below 4. Natural alkalinity is due to the presence of carbon

dioxide gas, CO2; HCO3¯ ions; CO32¯ ions and OH¯ ions which exist in the

limestone and dolomite. Alkalinity may also exist by caustic substances from

industry (potassium hydroxide, KOH and sodium hydroxide, NaOH), soil

additives in agriculture such as lime Ca(OH)2, superphosphate which is

mixture of Ca(H2PO4)2 and CaSO4 and soaps and detergents. The greater

natural cause for change in pH in a stream is the seasonal and daily variation

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in photosynthesis. Photosynthesis uses up hydrogen molecules which causes

the concentration of hydrogen ions to decrease and thus increase the pH value.

Due to the result obtained, we may see that both solution X and Y has

greater pH than distilled water. In this experiment we obtained that pH for

distilled water is 8.22 while in real, it should be 7.

H2O (l) ↔ H+(aq) + OH¯(aq)

[H+] = [OH¯] = 1.00 x 10-7

Kw = [H+][OH¯] = 1.00 x 10-14

pH = pOH = 7.00

From this, we may predict that there is a slight change in pH water due to the

existence of CO2 gas in the surrounding which allows the alkalinity of the

distilled water increased.

By comparing with both solution X and Y, it is obviously that solution

X and Y has been a bit polluted. The result proves that solution X is taken

from waste water while solution Y is taken from the stream. This is because,

normally waste water might have higher alkalinity due to the presence of lots

of ions inside while stream water may have either high pH or low. The sample

of water might be taken anywhere and the pH is depends on the position where

the sample is taken whether it is near to the industrial park, near to the village,

inside a jungle or else.

C. Turbidity

Turbidity is the cloudiness or haziness of a fluid caused by individual

particles (suspended solids) that are generally invisible to the naked eye,

similar to smoke in air. The measurement of turbidity is a key test of water

quality. Turbidity measured this way uses an instrument called a turbidimeter

or nephelometer with the detector setup to the side of the light beam. More

light reaches the detector if there are lots of small particles scattering the

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source beam than if there are few. The units of turbidity from a calibrated

nephelometer are called Nephelometric Turbidity Units (NTU).

Based on the result, the value of turbidity of water X is 8.88 NTU

while for the water Y is 8.41 NTU. The difference in value of turbidity will

determine the type of water. There is a correlation between turbidity and total

suspended solids (TSS) because it is due to the fact that the greater the amount

of total suspended solids (TSS) in the water, the murkier it appears and the

higher the measured turbidity. The major source of turbidity in the open water

zone of most lakes is typically phytoplankton, but closer to shore, particulates

may also be clays and silts. Thus, based on the result of the turbidity, it can

say that water X is waste water while water Y is stream water.

D. Total Suspended Solid (TSS)

Total Suspended Solid (TSS) is solid materials, including organic and

inorganic that are suspended in the water and can be entrapped by a filter. TSS

can consist of wide variety of material such as silt, plankton, decaying plant,

animal matter, industrial wastes and sewage. High concentrations of

suspended solids can cause many problems for stream health and aquatic life.

The value of TSS will affect physical parameter such as turbidity and

chemical parameter likes dissolved oxygen (DO). High concentration of

suspended solids can lower water quality by absorbing light. Water then

become warmer and lessen the ability of the water to hold oxygen necessary

for aquatic life. Besides that, high TSS can prevent light from reaching

submerged plants. As there is decreased amount of light passing through the

water, photosynthesis process also decreased (less oxygen is produced). The

combination or warmer water, less light and less oxygen makes it impossible

for some forms of aquatic life to exist.

If light is completely blocked from bottom dwelling plants, the plants

will stop producing oxygen and will die. As the plants are decomposed,

bacteria will use up even more oxygen from the water, thus lower the

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dissolved oxygen in water. Suspended solids will absorb heat from sunlight;

this makes temperature of water surface increase. In other hand make

dissolved oxygen levels fall because warmer water can hold less DO.

In this experiment, sample X which is from waste water has high value

of TSS than sample Y (stream water). High TSS in waste water means by

higher concentration of bacteria, nutrients, pesticides and metals. These

pollutants may attach to sediment particles on the land and be carried into

water bodies with storm water. In the water, the pollutants may be released

from the sediment or travel farther downstream. Suspended solids can result

from erosion from urban runoff and agricultural land, industrial wastes, bank

erosion, bottom feeders (such as carp), algae growth or wastewater discharges.

We can prevent suspended solids from entering our surface water.

Prevention methods include protection of the land in our watershed from

erosion by use of conservation tillage measures and giving urban runoff time

to settle out before reaching our surface waters.

II. Chemical Parameters

A. Dissolved Oxygen

The amount of oxygen in water is a good indicator of water quality and of the

kinds of life it will support. Water with an oxygen content above 6 parts per

million (ppm) will support game fish and other desire\able forms of aquatic

life. Water with less than 2 ppm oxygen will support mainly worms, bacteria,

fungi and other detritus feeders and decomposers. Oxygen is added to water

by diffusion from the air, especially when turbulence and mixing rates are

high, and by photosynthesis of green plants, algae and cyanobacteria. Oxygen

is removed from water by respiration and chemical processes that consume

oxygen.

One of the methods of assaying pollution levels is to measure

dissolved oxygen (DO) content directly by using an oxygen electrode. The DO

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content of water depends on factors other than pollution (for example

temperature and aeration). The effects of oxygen-demanding wastes on rivers

depend to a great extent on the volume, flow, and temperature of the river

water. Aeration occurs readily in a turbulent, rapidly, rapidly flowing river,

which is, therefore often able to recover quickly from oxygen-depleting

processes.

From the result, the value of dissolved oxygen in Y (stream water) is

low compared to the value of dissolved oxygen in (waste water). It is because,

the sample of stream water is taken from the area of polluted area. As we all

know, ‘Sungai Samak’ is one of the best place that most people have a picnic

especially during the weekend. So, many of them thrown all the rubbish and

food waste into the stream water. The addition of certain organic materials,

such as sewage, paper pulp, or food processing wastes, to water stimulates

oxygen consumption by decomposers. Due to this factor, the value of dissolve

oxygen (DO) in sample Y (stream water) is lower than DO in X (waste water).

QUESTION:

1. List three water-quality differences you think are typical of a polluted

stream and an unpolluted stream.

Parameter Unpolluted Stream    Polluted Stream

Dissolved  Oxygen The higher the amount

of oxygen the better

the quality. Trout- 10

ppm, Bass- about 7/8

ppm 0-3 Creatures flee

4-5 Creatures can

survive Greater than 5

Creatures thrive

Less than 5 ppm is

considered unacceptable

for most aquatic

organisms

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pH

(Hydrogen   ion

present)

Water with pH range

from 6.5-8.6 will have

little effect on life

processes

Water with pH less than

5 or greater than 9 will  

support little aquatic life

Biological Oxygen

Demand  (B.O.D.)

The lower the B.O.D.

the less organic matter

in a stream Less than 2

ppm is good

In a stream Less than 2

ppm is good High

B.O.D. indicates large

amounts of organic

matter Greater than 5

ppm means poor water

quality

2. What sources do you think contribute to the high strength of pollutant for

three parameters you have mentioned in question 1?

Garbage disposals, which have become a standard appliance in many

residential kitchens, contribute excessive organic loadings to the

infiltrative field and other system components. Usually installed under the

kitchen sink, disposals are basically motorized grinders designed to shred

food scraps, vegetable peelings and cuttings, bones, and other food wastes

to allow them to flow through drain pipes and into the wastewater

treatment system. Disposing of food waste in this manner eliminates the

nuisance of an odor of food wastes decaying in a trashcan by moving this

waste to the wastewater stream. Many states accommodate these

appliances by prescribing additional septic tank volume, service

requirements, or other stipulations (e.g., septic tank effluent filter, multiple

tanks, and larger infiltration field) that address higher BOD and TSS

loadings. For any septic system, the installation of a disposal causes a

more rapid buildup of the scum and sludge layers in the septic tank and an

increased risk of clogging in the soil adsorption field due to higher

concentrations of suspended solids in the effluent. Also, it means that

septic tank volumes should be increased or tanks should be pumped more

frequently.

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Eliminating the use of garbage disposals will significantly reduce the

amount of grease, suspended solids, and BOD in wastewater. Elimination

of garbage disposal use reduces the rate of sludge and scum accumulation

in the septic tank, thus reducing the frequency of required pumping. All of

these can improve wastewater system performance.

CONCLUSION:

1. The differences between polluted and unpolluted stream can be determine by

using chemical and physical parameters of water. Stream can be a river, a

junction where two rivers are combine to become one, upstream, downstream

and else. Different place that the water sample has been take present different

results. People keep doing a lot of activity related to water everyday such as

industry, camping, fishing, swimming, bathing and else. Those activities did

affect the water yet adds more content to the water. The water sample which is

taken from the place that is less of those activities will be unpolluted. Result

shown the X solution is more polluted compared to Y except for D.O. Thus,

this proof that X is waste water and Y is stream water.

2. In this experiment, we learnt on how to test the water quality by using

chemical and physical parameters of water. Water quality may be not be

determine only by using a parameter. This is not enough to ensure whether the

water is polluted or not, thus variety of instruments is used to stabilize our

result.

REFERENCES:

Anonymous (2009). Aus-e-tute. Acces from

http://www.ausetute.com.au/waterana.html on January 23, 2009.

Anonymous (2009). Bioworld products. Access from

http://www.adbio.com/science/analysis/water-temperature.htm on January 23,

2009.

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Anonymous (2009). The pH of distilled water. Access from

http://www.coolschool.ca/lor/CH12/unit4/U04L07.htm on January 24, 2009.

Anonymous (2009). Turbidity. Access from

http://waterontheweb.org/under/waterquality/turbidity.html on January 23,

2009

Anonymous (2009). Turbidity. Access from http://en.wikipedia.org/wiki/Turbidity on

January 23, 2009

Murphy, S. (2007). General Information on Solids. Access from

http://bcn.boulder.co.us/basin/data/BACT/info/TSS.html on January 24, 2009.

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TITLE:EXPERIMENT 1B: Water and Wastewater Analysis (Biological Parameters)

INTRODUCTION:

Wastewater is any water that has been adversely affected in quality by anthropogenic

influence. It comprises liquid waste discharged by domestic residences, commercial

properties, industry, and/or agriculture and can encompass a wide range of potential

contaminants and concentrations. A stream is a body of water with a current, confined

within a bed and stream banks. A stream bed is the channel bottom of a stream or

river or creek; the physical confine of the normal water flow. The lateral confines

(channel margins) during all but flood stage are known as the stream banks or river

banks.

Coliform bacteria are the commonly-used bacterial indicator of sanitary

quality of foods and water. They are defined as rod-shaped Gram-negative non-spore

forming organisms that ferment lactose with the production of acid and gas when

incubated at 35-37°C. Coliforms are abundant in the feces of warm-blooded animals,

but can also be found in the aquatic environment, in soil and on vegetation. In most

instances, coliforms themselves are not the cause of sickness, but they are easy to

culture and their presence is used to indicate that other pathogenic organisms of fecal

origin may be present. Fecal pathogens include bacteria, viruses or protozoa may of

which are parasites.

OBJECTIVES:After conducting this experiment student should be able to:

1. Learn the technique for evaluating water quality in term of biological parameters.

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METHODOLOGY:1. A sterile water is used to collect a sample of water from selected wastewater.

Sampling in stream must be away from the bank and avoid collecting sediment

from the bottom. The sample has been processed before six hours have

elapsed.

2. The lid of petri dish is lift in turn just high enough to allow you to pour about

1 ml of water sample into the eosin blue methylated agar medium. The content

is gently swirled to mix water with the agar.

3. Petri dish is turned upside down.

4. Petri dish is incubated for 24 hours at 37 ºC.

5. Number of bacterial colonies (yellow colonies) that grow on the plate is

counted after 24 hours.

6. Environment is ensuring to be sterile during the test.

RESULT:

PETRI DISH NUMBER OF COLONIES

X (waste water) 1

Y (stream water) 0

Unknown 0

DISCUSSION:Those chemical and physical parameters are used to give a broad picture that defines

the aquatic environment compared to the biological parameter which will examine the

living components of the system. Biological parameter may determine the extent it

has been affected by human activity. Biologically, there are many ways to determine

the quality of the water such as by using Biochemical Oxygen Demands (B.O.D)

method or by using the chlorophyll a and fecal coliform. In this class, we have chose

one biological test which is by using the fecal coliform.

Fecal coliform bacteria are found in the feces of humans and other warm-

blooded animals. Fecal coliform bacteria naturally occur in the human digestive tract,

and aid in the digestion of food. These bacteria can enter rivers directly or from

agricultural and storm runoff carrying wastes from birds and mammals and from

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human sewage discharged into the water. Fecal coliform bacteria can be harmful to

humans in excessive amounts but are more frequently used as an indicator of other

microbial pathogens.

Fecal coliform by them are not dangerous at all. It is a part of the pathogenic

species if exist in a large number. Pathogenc organisms include bacteria, viruses and

parasites that cause diseases and illnesses. If the coliform is found very high, for

examples it exceed 200 colonies in 100 mL of water sample, then there is a greater

chance that the phatogenic organisms present. Thus, a person swimming inside the

water may be caused by diseases such as typhoid fever, hepatitis, gastroentitis,

dysentery and ear infection that attacked by the pathogens. Pathogens may easily

enter our body part through skin, nose, mouth or ears.

In our experiment, we cannot immediately get the result. Those samples

should be kept 24 hours in a 37 ºC temperature. This will allow those bacteria inside

the samples did the lactose fermentation. The presence of colonies after 24 hours

indicate which water has been highly contaminated. From the result obtained, it is

shown that only one colony appeared in the wastewater while there are no colonies

inside the stream water and the unknown sample. We may predict that the wastewater

has been contaminated compared to others. It is absolutely prove the definition of

wastewater which said that wastewater is taken from industrial waste, sewage or else.

Water from those places may contain a lot of dirtiness, bacteria and viruses.

Normally, wastewater will be treating. No colony appears in stream water and

unknown solution indicates that stream water is safe for us. Thus, people or animals

may swim, drink, and else using the stream water. Stream water normally refers to the

river banks. They are safe to be used in our daily life. Those indicators has proof it. It

is shown that the unknown solution also do not have the colony so we can assume that

the unknown solution might be the stream water.

CONCLUSION:Biological parameters may used to complete up the examination of water quality. It is

very expensive of using the chemical and the physical parameters because expensive

tools are needed. Therefore, biological parameter is one of the way to reduce the cost

of determining the water quality.

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REFERENCES:Anonymous (2009). Adopt-a-stream. Access from

http://www.adopt-a-stream.org/parameters.php on January 30, 2009

Anonymous (2009). Biological parameters – fecal coliform bacteria. Access from

http://www.projectsearch.org/downloads/chapter9.pdf on January 30, 2009

Anonymous (2009). Coliform bacteria. Access from

http://en.wikipedia.org/wiki/Coliform on January 30, 2009

Anonymous (2009). Fecal coliform test. Access from

http://www.indiana.edu/~bradwood/eagles/fecal.htm on January 30, 2009

Anonymous (2009). Physical, chemical and biological water parameters. Access from

http://www.uncwil.edu/cmsr/aquaticecology/lcfrp/WQ%20Reports/96-97/

parameters.htm on January 30, 2009

Anonymous (2009). Stream. Access from http://en.wikipedia.org/wiki/Stream on

January 30, 2009

Anonymous (2009). Stream banks. Access from

http://en.wikipedia.org/wiki/Stream_bank on January 30, 2009

Anonymous (2009). Waste water. Access from

http://en.wikipedia.org/wiki/Wastewater on January 30, 2009

Joe Hill (2004). Susquehanna river water quality monitoring. Access from

http://www.oneonta.edu/academics/biofld/PUBS/ANNUAL/2004/Monitoring

%20the%20fecal%20coliform%20bacteria.pdf on January 30, 2009

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