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The Volume of a Cylinder with a radius of 5ft and a height of 8 ft is ___ cubic FT    
  A. 157 (Your Answer)   B. 328   C. 451   D. 628 (Correct Answer)   Explanation Volume of a cylinder from radius = P(pie = 3.14) X Radius square (Radius X Radius) X height
= 3.14 X (5ft radius X 5ft radius) X 8 ft high
= 3.14 X 25 ft square X 8ft high = 628 Cubic Feet
The volume of a 100FT diameter tank that is 12ft deep is ____ Cubic FT
  A. 94,200 (Your Answer)   B. 98,600   C. 103,300   D. 285,200   Explanation Volume of a cylinder from diameter = .785 X diameter square(diameter X Diameter) X depth
= .785 X (100 ft diameter X 100ft diameter) X 12ft deep
= .785 X 10,000 square ft X 12 ft = 94,200 Cubic feet
  A chemical commonly used to raise PH is  
  A. Alum   B. Calgon   C. Chlorine   D. Lime (Correct Answer)
  The indicator organisms used to determine contamination of drinking water are
  Coliform group
The packing around the shaft of a centrifugal pump should be
  tightened just enough to allow an occasional drop of liquid to escape
  The chemical symbol for iron is
  Fe
One pound per square inch of pressure will raise water ____ Feet
  2.31
The pressure gauge reading at the base of a tank filled to a depth of 1 ft is ___ PSI
  0.433
  Explanation 1 psi = 2.31 ft dividing your pressure by footage gives you the per food pressure.
1/2.31 = 0.4329 rounded up to .433
  The multiple tube fermentation test consists of three distinct tests. These tests, in the order performed, are the
  Presumptive, confirmed and completed tests
  Polyphosphates may be used in water treatment to retard corrosion and
. calcium scale
Calcium hypochlorite is formulated as a
  powder
  Determining the pH of water is one of the important test of water quality. The results of the pH test indicate the
  hydrogen ion activity
If a fire hydrant requires a nozzle pressure of 100 PSI, what head of water must be used to supply it?
  231 ft
  Explanation 1PSI = 2.31 ft
so multiply 2.31 ft per psi by needed psi
2.31*100=231
Carbon dioxide in water will
  lower pH
Mechanical seals are being installed in pumps because
  packing requires an undesirable leakage that seals eliminate
  A water treatment plant receives an average flow of 261 gpm. What is the daily total flow at the plant?
  Explanation 261 gpm * 60 minutes in a hour = 15,660 gph * 24 hours per day = 375,840 gpd / 1 million = .37584 mgd rounded to .38 mgd .38 mgd
  The difference between the amount of chlorine added to water and the amount of residual chlorine remaining at the end of a specified contact period is
. chlorine demand
A pH reading of 6.0 in raw water indicates the sample is
acid
The flow is 35,000 gpd. this is _____MGD
  .035
  Explanation 35,000 gpd /1 million = .035
The pH value of 7.0 is considered to be
  neutral
  What is the surface area of a clarifier 40ft in diameter?    
  Explanation Area of a circle from diameter = .785 * square diameter =
.785*40*40 = 1256 sqare feet 1256 sq ft
Coagulation and sedimentation alone cannot remove all the trubidity and suspended matter in raw water. The final step in the removal of suspended matter in water is
  filtration
  The pressure gauge reading at the base of a tank filled to a depth of 1 ft is ___ PSI
  0.433
  The Volume of a Cylinder with a radius of 5ft and a height of 8 ft is ___ cubic FT    
  628
  Explanation Volume of a cylinder from radius = P(pie = 3.14) X Radius square (Radius X Radius) X height
= 3.14 X (5ft radius X 5ft radius) X 8 ft high
= 3.14 X 25 ft square X 8ft high = 628 Cubic Feet
  When Collecting a distribution system sample for bacteriological testing, the person collecting the sample should allow the water to run ____ before filling the sample bottle
  as long as necessary to permit clearing of the service line
  Which test can be performed to improve the jar test and interpretation of the results
Alkalinity (before and after)
  Best answer
What are jar tests designed to do?
To show the effectiveness of chemical treatment in a water treatment facility
What are the greatest sources of errors in laboratory tests?
  Failure to communicate testing procedures to management
  Improper sampling

Lack of enough mixing during testing
  Poor sampling preservation
  Which test can be performed to improve the jar test and interpretation of the results?
  Alkalinity (before and after)

  Filtered turbidity of the supernatant
  pH (before and after)
Turbidity of the supernatant (before and after)
  The chlorine demand of water varies with which factors?
  Amount of chlorine applied
  Length of contact time
  PH
  Temperature
When performing a coliform test using the membrane filger method, what do the letters CFU stand for?
  Colony formation unit
The Greater the intensity of scattered light, the lower the turbidity
  Best answer
How can water treatment plant operators obtain a good index of the degree of bacteriologic safety of a water supply without testing for specific pathogenic microorganisms?
  Analyzing the water for the presence of an "indicator organism," the coliform group of bacteria.
  How do operators use the results of turbidity testing?    

  To detect problems in coagulation and sedimentation
  To recognize changes in raw water quality To troubleshoot filtration problems
What is a chemical compound?
A substance composed of two or more different elements and whose composition is constant
Obtaining good results from laboratory water testing depends to a great extent upon which factors?
  Ensuring that the sample taken is truly representative of the water under consideration.

  Protecting and preserving the samples until they are analyzed
  Using proper sampling techniques
By relating laboratory results to treatment operations, the water treatment operator can perform which tasks?
  Determine the efficiency of the treatment processes
  Identify potential problems before they affect finished water quality
  Select the most effective operational procedures
Fires are classified as A, B, C, or D fires based on which item
The type of material being consumed
 How can operators obtain the necessary information to monitor the treatment processes and to ensure a safe and pleasant-tasting drinking water for all who use it?    
  By laboratory quality control tests
What is a representative sample?  
A sample portion of material or water that is as nearly identical in content and consistency as possible to that in the larger body of material or water being sampled
  pH plays an important role in which water treatment processes?    
  A. Coagulation (Your Answer)   B. Corrosion control (Your Answer)   C. Disinfection (Your Answer)   D. Filtration   E. Softening (Missed
Which precautions should be considered when measuring the chlorine residual?
For accurate results, careful pH control is essential

  If nitrogen trichloride or chlorine dioxide are present, special procedures are necessary

  If the sample contains oxidized manganese, an inhibitor must be used
  Operators using the DPD colorimetric method need to be aware of the potential error of a "false positive" chlorine residual reading
  Samples should be analyzed as soon as possible after collection
What is the use of a flask?
  To contain and mix chemicals
Which precautions should be considered when measuring the turbidity of water?



 
Discard scratched or etched sample tubes (Missed)


 
B.
Fill the tubes with samples and standards that have been agitated thoroughly, and allow sufficient time for bubbles to escape. (Missed)


 
C.
Sample tubes must be kept scrupulously clean, both inside and out (Missed)


 
D.
Turbidity of a sample an change after the sample is collected and shaking the sample will not re-create the original turbidity. (Missed)


 
E.
Turbidity should be measured in a sample as soon as possible to obtain accurate results. (Your Answer)


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