Practice Exam #2

Front 1

The pumping water level is best defined as the distance from the top of the well to the

Back 1

Water after the pump has been operating for a period of time

Front 2

When bringing community water service to a home with a private well, what is the most positive method of preventing a cross connection between two systems

Back 2

Complete isolation between the two systems using an air gap

Front 3

Chlorine will destroy bacteria most rapidly at which pH?

Back 3

7

Front 4

How many pounds of a chemical applied at the rate of 3mg/L are required to dose 200,000 gallons?

Back 4

5 lbs

Solution: 3mg/L x 02.MGD x 8.34lbs/gal=5 lbs

Front 5

Which document provides a profile of hazardous substances?

Back 5

MSDS

Front 6

What federal law is designed to protect the safety and health of operators?

Back 6

OSHA

Front 7

A mixture of air and gas is considered hazardous when the mixture exceeds what percentage of the lower explosive limit (LEL)?

Back 7

10%

Front 8

What safety measure must an operator follow prior to working on electrical equipment?

Back 8

Lock out and tag out all electrical switches.

Front 9

What is the correct procedure for mixing acid and water?

Back 9

Acid is added slowly to the water

Front 10

Unless the state has granted a waiver, how many coliform samples are required per month for a water system serving a population between 25 and 100?

Back 10

1

Front 11

Calculate drawdown, in feet, using the following data.
-The water level in a well is 20 feet below the ground surface when the pump is not in operation.
-The water level is 35 feet below the ground surface when the pump is in operation

Back 11

15 feet

Solution: 35 feet- 20 feet= 15 feet

Front 12

What device measures the flow rate of gases or liquids?

Back 12

Rotameter

Front 13

How often should operation data, such as flow rate, amount of water treated, dosage of chemical, and reservoir levels be recorded?

Back 13

Daily

Front 14

What safety procedure should an operator always follow when mixing a solution of sodium hypochlorite (liquid bleach) and fresh water?

Back 14

Wear goggles and gloves when handling hypochlorite

Front 15

What is the process of adding chlorine to water until the chlorine demand has been satisfied called?

Back 15

Breakpoint chlorination

Front 16

Which of the following terms refers to excessive internal pressure, which may be several times the normal operating pressure and can seriously damage hydropneumatic tanks,valves, and the piping network?

Back 16

Water Hammer

Front 17

Chlorine demand is satisfied at the point when

Back 17

The reaction of chlorine with organic and inorganic materials stops

Front 18

What type of fire extinguisher should be used for fires with live electricity present?

Back 18

Class C

Front 19

What source of water has the greatest natural protection from bacterial contamination?

Back 19

Deep well in gravel

Front 20

What causes water to move through pores in soil and rocks?

Back 20

Gravity

Front 21

According to the Safe Drinking Water Act, the basic definition of a public water supply system is any water system that supplies water for human consumption that serves at least

Back 21

15 service connections or 25 or more persons for 60 or more days a year.

Front 22

What agent is responsible for reporting laboratory results to the regulatory agency?

Back 22

Water system owner

Front 23

When should water quality samples for chlorine residual be analyzed?

Back 23

Immediately

Front 24

Which of the following should not be used to draw a sample into a pipet?
Mouth
Bulb
Pump
Straw

Back 24

Mouth

Front 25

What term is used when a water utility divides its total operating expenses into the total revenue?

Back 25

Operating ratio

Front 26

the major source of error when obtaining water quality information is improper

Back 26

Sampling

Front 27

The most important responsibility of an operator is to provide

Back 27

Safe drinking water

Front 28

Calculate the average weekly flow for a system with the following data.
Sunday - 3,000 gallons
Monday- 4,000 gallons
Tuesday- 3,500 gallons
Wednesday- 2,000 gallons
Thursday- 3,000 gallons
Friday- 3,500 gallons
Saturday- 2,000 gallons

Back 28

3,000 gpd

Front 29

a ditch that is 4.5 feet wide, 6 feet deep, and 120 feet long has to be dug for a water line. How many cubic yards of material must be removed?

Back 29

120 cubic yards

Solution: convert feet to yards, then multiply the 3 figures.

Front 30

Which of the following causes taste problems and has a rotten egg odor?

Back 30

Hydrogen sulfide

Front 31

Which of the following should an operator investigate first when well pump and control problems occur?

Back 31

Electricity

Front 32

Calculate the volume, in gallons, of a tank that is 75 feet long, 20 feet wide, and 10 feet deep.

Back 32

112,200 gallons

Solution= 75ft x 20ft x 10 ft= 15,000 cu ft

15,000 cu ft x 7.48gal/cu ft= 112,200gal.

Front 33

Dynamic head is best described as the

Back 33

Total energy that a pump must develop for pumping to take place

Front 34

How often should preventive maintenance for equipment be performed?

Back 34

According to manufacturer recommendations

Front 35

What is the most important reason for maintaining a continuous positive pressure throughout the distribution system?

Back 35

Prevent contamination from backflow

Front 36

After a new water main is installed and pressure tested it should be

Back 36

Filled with a solution of 25ppm to 50ppm free chlorine for at least 24 hours prior to flushing

Front 37

Which of the following is the most important reason to keep daily records of operational data?

Back 37

Document the safe drinking water has been delivered to customers

Front 38

What are the two main causes of hardness in water?

Back 38

Calcium and magnesium

Front 39

Most pumps must be primed before startup in order to

Back 39

Start the flow of water

Front 40

Which of the following are two types of samples?

Dessicator and gooch
Wet and dry
Buret and flask
Grab and composite

Back 40

Grab and composite

Front 41

What test method best determines chemical feed/dosage rates

Back 41

Jar

Front 42

How should samples that cannot be analyzed immediately be maintained until the analysis is conducted?

Back 42

Preserved

Front 43

What are the two most important safety concerns when entering a confined space?

Back 43

Oxygen deficiency and hazardous gases

Front 44

Two columns of water are filled completely at sea level to a height of 88 feet. Column A is 0.5 inches in diameter. Column B is 5 inches in diameter. What will two pressure gauges, one attached to the bottom of each column, read?

Back 44

Column A= 38.1 psi
Column B= 38.1psi

Solution: 88 feet x 0.433= approximately 38.1 psi

Front 45

Calculate the chlorine demand using the following data.
-Raw water flow is 0.75 MGD
-Chlorinator feed rate is 4.0 mg/L
-Chlorine residual is 1.8 mg/L

Back 45

2.2mg/L

Solution: 4.0mg/L- 1.8mg/L=2.2mg/L

Front 46

To ensure that the water supplied by a public water system meets federal and state requirements, the water system operator must regularly collect samples and

Back 46

Send all analyses results to the State periodically

Front 47

What is the purpose of a check valve?

Back 47

Act as automatic shutoff valve when the pump stops

Front 48

What federal law regulated public water supplies?

Back 48

Safe Drinking Water Act

Front 49

If a customer complains about the drinking water characteristics, the operator should record the complaint and

Back 49

Investigate immediately

Front 50

According to the USEPA drinking water regulations, failure of a public water system to comply with applicable monitoring requirements and subject to Tier 3 public notice requires notifications to all customers within

Back 50

1 year