Water Treatment ch 3 Flashcards
Local conditions have little influence on the methods of managing lakes and reservoirs used for domestic water supplies
T or F?
False
The amount and type of public use allowed on reservoirs has been standardized by law and regulations
T or F
False
Few of the conditions which adversely affect water quality in domestic water supply reservoirs result from the impacts of man’s activities upon the environment
T or F
False
Objectionable tastes and odors in domestic water supplies are often related to the occurrence of algal blooms.
T or F
True
Many conventional water treatment plats are capable of reducing tastes and odors to acceptable levels when operated properly
T or F
True
Algae can die of oxygen starvation
T or F
True
In a monomictic lake, during winter months, the lake temperature is uniform from top to bottom
T or F
True
Mixing occurs between the epilimnion and the hypolimnion zones in thermally stratified lakes
T or F
False
Fish kills can result from algae clogging the gills of
T or F
True
Once vegetation removal is accomplished at the reservoir site, regrowth should be controlled until the reservoir is filled.
T or F
True
Chlorination of a water supply may either increase or decreased tastes and odors in drinking water
T or F
True
The best tool which can be used for managing watersheds in most cases is the regulatory process
T or F
True
Phosphate-base fertilizers usually do not cause the water quality problems caused by nitrogen fertilizers because of the soil-binding characteristics of phosphate compounds
T or F
True
All algae react the same way to copper sulfate
T or F
False
Destratification always increases the number of algae blooms in reservoirs
T or F
False
With complete destratification, temperatures in a reservoir will be nearly uniform from top to bottom
T or F
True
Through proper design and operation, reservoir destratification systems can be used to manipulate temperatures and dissolve oxygen content to desired levels
T or F
True
The operator of a small water supply system must be able to manage the watershed as well as operators of large systems
T or F
True
Records are very valuable only when they are completed and filed by lab personnel
T or F
False
The inlet to a single-level intake is usually located near the water surface
T or F
False
Nutrients act as a(n) __________ in a lake.
a) Algicide
b) Chemical stabilizer
c) Destratifier
d) Fertilizer
e) Purifier
d) Fertilizer
Reservoirs which are rich in nutrients and very productive in terms of aquatic animal and plant life are commonly referred to as:
a) Dimictic
b) Eutrophic
c) Mesotrophic
d) Oligotrophic
e) Thermophylic
b) Eutrophic
What problems may be created for operators by algal blooms in domestic water supply reservoirs?
a) Dissolved oxygen depletion
b) Increased pH which reduces chlorination efficiency
c) Increased organic loadings
d) Shortened filter runs
e) Tastes and odors
a, b, c, d, e
all correct
What water quality problems are caused by iron and manganese in drinking water?
a) dirty water
b) dissolved oxygen depletion
c) high coliform counts
d) staining clothes
e) staining porcelain fixtures
a) dirty water
d) staining clothes
e) staining porcelain fixtures
Proper management practices which can increase recreational values of a reservoir include
a) Controlling man’s activities on the watershed
b) increasing the rate of oxygen depletion
c) reducing large mats of algae
d) reducing scums of algae
e) removing vegetations before flooding
a) Controlling man’s activities on the watershed
c) reducing large mats of algae
d) reducing scums of algae
e) removing vegetations before flooding
Trees and brush should be removed from areas to be flooded by reservoirs to reduce the _______ loading.
a) iron and manganese
b) nutrient
c) organic
d) silt
e) turbidity
b) nutrient
c) organic
Anaerobic conditions in the hypolimnion of a reservoir can cause
a) algal scums
b) fish kills
c) high organic loadings
d) iron and manganese problems
e) rotten egg odors
b) fish kills
d) iron and manganese problems
e) rotten egg odors
Algal blooms in lakes and reservoirs can be controlled by
a) chemical methods
b) limiting nutrient recycling
c) preventing nutrient inflow
d) removal of algae by filtration
e) removal of nutrients by filtration
ANSWER PENDING
Which of the following water quality indicators have a significant impact on the efficiency of copper sulfate as an algicide?
a) alkalinity
b) dissolved oxygen
c) pH
d) suspended matter
e) water temperature
a) alkalinity
c) pH
d) suspended matter
e) water temperature
Which chemical is used to make copper sulfate effective in highly alkaline waters (greater than 150 mg/L alkalinity)
a) citric acid
b) hydrochloric acid
c) nitric acid
d) phosphoric acid
e) sulfuric acid
a) citric acid
The reasons for using destratification programs in a domestic water supply reservoirs include improving
a) aesthetics
b) fisheries
c) hydroelectric power production
d) recreational power power production
e) water quality
a) aesthetics
b) fisheries
d) recreational power power production
e) water quality
Important water quality indicators that should be considered in a lake destratification program include
a) carbon dioxide
b) coliforms
c) dissolved oxygen
d) hardness
e) temperature
c) dissolved oxygen
e) temperature
Factors affecting watershed management programs include
a) intake structure
b) size of watershed
c) topography
d) vegetative conditions
e) water quality problems
b) size of watershed
c) topography
d) vegetative conditions
e) water quality problems
Which of the following watershed practices can affect water quality in a water supply reservoir?
a) control of land use
b) livestock grazing
c) oil and gas exploration and drilling
d) septic tank leaching systems
e) soil conservation programs
a) control of land use
b) livestock grazing
c) oil and gas exploration and drilling
d) septic tank leaching systems
e) soil conservation programs
Water quality laboratory analysis which may be best performed by commercial laboratories include
a) dissolved oxygen
b) pesticides
c) radioactivity
d) temperature
e) trihalomethanes
b) pesticides
c) radioactivity
d) temperature
e) trihalomethanes
Intake facilities should prevent _______ from entering a water supply system.
a) algal scums
b) fish
c) hardness
d) iron and manganese
e) tastes and odors
a) algal scums
b) fish
Water quality problems caused by anaerobic water entering the intake-inlet include high concentrations of:
a) dissolved oxygen
b) hardness
c) hydrogen sulfide
d) iron
e) manganese
c) hydrogen sulfide
d) iron
e) manganese
Types of intake screens include
a) burlap sacks
b) slotted
c) vee wire
d) window screens
e) woven wire
b) slotted
c) vee wire
e) woven wire
Methods of cleaning intake screens include
a) brushing with bristle brushes
b) drying and brushing
c) jetting with high pressure
d) reversing the slow
e) vacuuming up the debris
a) brushing with bristle brushes
c) jetting with high pressure
d) reversing the slow
Factors that can adversely affect water quality in lakes and reservoirs include
a) agriculture runoff
b) drainage from mining areas
c) grazing of livestock
d) logging operations
e) runoff from urban areas
a) agriculture runoff
b) drainage from mining areas
c) grazing of livestock
d) logging operations
e) runoff from urban areas
Objectionable tastes and odors in a domestic water supply may be caused by
a) algae
b) hardness
c) hydrogen sulfide
d) overturns
e) photosynthesis
a) algae
c) hydrogen sulfide
d) overturns
Trihalomethanes are often formed during chlorination by reactions with
a) acid rain
b) ammonia
c) iron and manganese
d) natural organic materials
e) nutrients
d) natural organic materials
Purposes of reservoir management programs include
a) improvement and maintenance of fishery values
b) improvement and maintenance of recreational values
c) improvement and maintenance of water quality
d) improvement and maintenance of watershed aesthetics
e) reduction of water treatment costs
a) improvement and maintenance of fishery values
b) improvement and maintenance of recreational values
c) improvement and maintenance of water quality
e) reduction of water treatment costs
What is the surface area of a rectangular setting basin 60ft long and 15 wide?
a) 90 sq ft
b) 360 sq ft
c) 400 sq ft
d) 500 sq ft
e) 900 sq ft
e) 900 sq ft
What is the surface area of a circular clarifier 40 feet in diameter
a) 314 sq ft
b) 1,256 sq ft
c) 1,600 sq ft
d) 2,512 sq ft
e) 5,024 sq ft
b) 1,256 sq ft
Calculate the volume cubic ft, of a rectangular setting basin 8 ft deep, 15 ft wide, and 60 ft long
a) 120 cu ft
b) 480 cu ft
c) 900 cu ft
d) 4,800 cu ft
e) 7,200 cu ft
e) 7,200 cu ft
Calculate the volume in a cubic feet of a circular clarifier 7 feet deep and 40 feet in diameter.
a) 7,200 cu ft
b) 8,800 cu ft
c) 11,200 cu ft
d) 24,800 cu ft
e) 35,200 cu ft
b) 8,800 cu ft
How many pounds of copper sulfate will be needed to dose a reservoir with 0.5 mg/L copper? The reservoir volume is 20 million gallons. The sulfate is 25 percent copper.
a) 125 lbs
b) 165 lbs
c) 335 lbs
d) 835 lbs
e) 1,335 lbs
c) 335 lbs
