Water and wastewater treatment Flashcards
Corrective actions to be taken in response to adverse results can be found in
- Regulation 170/03 (Drinking Water Systems)
- Ontario Water Resources Act (OWRA)
- Regulation 242/05 (Compliance and Enforcement Regulation)
- None of the above
Regulation 170/03 (Drinking Water Systems)
Samples confirmed in the presence-absence test must also be tested for
- Shigella
- Salmonella
- Escherichia coli
- Giardia lamblia
Escherichia coli
How many coliform positive samples are allowed each for water systems that collect less than 40 samples per month?
- 1
- 3
- 4
- 2
1
If a water sample tests positive for coliforms, the system must collect a set of repeat samples within
- 36 hours
- 18 hours
- 48 hours
- 24 hours
24 hours
Water systems are required to achieve at least ____ removal and/or inactivation of viruses between a point where the raw water is not subject to recontamination by surface water runoff and a point downstream before or at the first customer.
- 2.5 log
- 3 log
- 4 log
- 2 log
4 log
Which Ontario Act is the main legislation governing drinking water in Ontario?
- Environmental Bill of Rights Act
- Sustainable Water and Sewage Systems Act
- Ontario Water Resources Act
- Safe Drinking Water Act
Safe Drinking Water Act
It is the hardest to kill the organism that causes which of the following illnesses?
- infection hepatitis
- cryptosporidiosis
- typhoid
- cholera
cryptosporidiosis
Giardia lamblia species are
- protozoans
- viruses
- bacteria
- metazoans
protozoans
Which is/are the ideal indicator for pathogens?
- Salmonella species
- Coliform group bacteria
- Gram-negative coccibacilli
- Gram-negative cocci
Coliform group bacteria
What is the main purpose of the Safe Drinking Water Act?
- Sample and test drinking water
- Supervise drinking water systems
- Protect human health
- Certify operators
Protect human health
Convert 4.5 ft to meters.
- 1.4 m
- 15 m
- 3.7 m
- 4.5 m
1.4 m
Convert 32 m² to square feet.
- 3785 ft²
- 345 ft²
- 32 ft²
- 3.0 ft²
345 ft²
Convert 35.1 cfs to gpm. • 18 300 gpm • 15 800 gpm • 17 600 gpm • 14 200 gpm
15 800 gpm
Flow through a channel 5.8 ft wide is 20.3 cfs. If the velocity is 1.4 ft/sec, how deep is the water in the channel? • 2.3 ft • 2.9 ft • 2.5 ft • 2.7 ft
2.5 ft
Determine the circumference of a clarifier, given that the radius is 95 ft. • 600 ft • 500 ft • 300 ft • 400 ft
600 ft
Convert 7.7 million gallons per day (mgd) into cubic feet per second (cfs). • 15 cfs • 10 cfs • 19cfs • 12 cfs
12 cfs
Determine the volume (in gallons) for a pipe completely full of water given the following data: diameter = 1.5 feet, length = 1.09 miles
- 65 000 gal
- 68 000 gal
- 74 000 gal
- 76 000 gal
76 000 gal
Calculate the area of a circular reservoir with a diameter of 411 ft in square feet (ft²). • 125 000 ft² • 133 000 ft² • 112 000 ft² • 108 000 ft²
133 000 ft²
Calculate 81.5% of 316. • 232 • 258 • 219 • 267
258
Convert 68°F to °C. • 37°C • 20°C • 65°C • 45°C
20°C
Which method can be used to control scale and corrosion? • sequestering • chelation • softening • pH and alkalinity adjustment with lime
pH and alkalinity adjustment with lime
The corrosion process can be accelerated by certain bacterial organisms because they produce which chemical?
- N2
- CO2
- CaCO3
- MgCO3
CO2
Loss of pressure due to friction in a pipeline is caused by
• roughness of the inside of the pipe
• difference in elevation from pipe inlet to outlet
• steepness of pipe slope
• diameter of the pipe
roughness of the inside of the pipe
An example of mechanical cleaning of distribution pipes includes • swabbing or pigging • increasing the flow rate • wet tapping • flushing
swabbing or pigging
What is the recommended minimum water pressure in a distribution system at any time, including fire flow conditions? • 30 psi or 207 kPa • 15 psi or 103 kPa • 40 psi or 276 kPa • 20 psi or 138 kPa
20 psi or 138 kPa
What is the pressure (in lb/ft²) 189 ft below a lake's surface is the lake is 386 ft in depth? • 11 789 lb/ft² • 11 791 lb/ft² • 11 793 lb/ft² • 11 800 lb/ft²
11 789 lb/ft²
What is the colour of oxidized iron? • red-brown • dark brown • red • yellow
red-brown
A channel (1.5 m wide) has water flowing to a depth of 0.75 m. What is the daily flow in the channel if the velocity of the water is 0.6 m/s? • 1440 L/min • 0.675 m³/s • 58 320 m³/d • 64 800 L/d
0.675 m³/s
A lake is 107 ft deep. Which is the psi on the bottom? • 45.6 psi • 46.3 psi • 45.2 psi • 44.8 psi
46.3 psi
Most of the carbon dioxide in groundwater originates from • plant respiration • biological oxidation of organic matter • animal respiration • weathering rocks
cadmium