Water Flashcards
Hydro pneumatic or pressure-tank water systems are suitable for ..
small communities, housing developments, private homes, and estates, camps, food services opertaions, and hotels
The hydro pneumatic tank typically contains ___ of its volume as water.
20 percent
Water containing nitrates generally indicates…
evidence of previous pollution
Hydrogen sulfide can be fatal at exposure of
300ppm
Back siphonage is prevented by all of the following except:
a. barometric loop
b. vacuum breaker
c. air gap separation
d. back pressure units
a. barometric loop
Of the following, which is not a variable to be considered when deciding upon a safe distance between a well and a sewage disposal system?
a. well construction
b. the number of individuals using the well
c. the volume, strenght, type and dispersion of polluted material
d. soil and texture
B. the number of individuals using the well
Microbial pollution travels only a short distance through
dried out cracked clay
Typically an abundant supply of ground water may be yielded from
sedimentary rock
Which of the following is used to properly seal a drilled well to prevent contamination of the water supply?
a. epoxy
b. bentonite clay
c. grouting
d. a runner seal
C. grouting
Which of the following compounds would not contribute to water hardness?
a. calcium sulfate
b. magnesium sulfate
c. calcium chloride
d. sodium chloride
d. sodium chloride
The quiescent settling of water such as would occur in a reservoir, lake, or basin without the aid of a chemical is known as
plain sedimentation
Which of the following is not a commonly accepted method or device to prevent back siphonage:
a.vacuum breaker
b.cross connections
c. air gap separation
d. back pressure units
B. cross-connections
Which of the following compounds can be used full strength to disinfection:
a. perchloron
b. calcium hypochlorite
c. chlorinated lime
d. sodium hypochlorite
d. sodium hypochlorite
The presence of which of the following elements in water treatment plant effluent is used as a measure of filtration efficiency?
a. copper
b. aluminum
c. zinc
d. lead
b. aluminum
Proper disinfection of water using chlorine depends on the concentration of chlorine plus which of the following?
a. temperature of the water
b. pH of the water
c. contact period time
d. all of the above
d. All of the above
Which of the following is used to control the growth of algae and protozoa?
a. copper sulfate
b. aeration
c. nitrates
d. filtration
d. filtration
Granular activated carbon (GAC) filters are used to
a. treat water for soft drinks
b. remove taste and odor
c. remove synthetic organic chemicals
d. all of the above
d. all of the above
GAC removes only taste and odors and chemicals. GAC cannot remove metals
Trihalomethanes are synthetic organic chemicals primarily created pre or post chlorination?
during the pre-chlorination process
Often over 90% of sodium arsenate can be removed by
a. filtration
b. coagulation
c. ion exchange
d. all of the above
b. coagulation
The Langelier index is used to determine the point of stability of
calcium carbonate
A well casing should be equipped with a vent and installed…
with concrete as grout
Cross connections are frequent causes of diseases resulting from
a. back siphonage of contaminated chemicals
b. back flow of biologically contaminated liquids
c. connection of the water supply to the sewer system
d. all of the above
d. all of the above
The flushometer valve is typically protected by…
a non pressure type vacuum breaker
When using pre-settling reservoirs to eliminate heavy turbidity or pollution before treatment, what is the desirable retention time?
a. 8 hours
b. 1 week
c. 2 to 3 days
d. 1 month or longer
c. 2 to 3 days
If sufficient amounts of activated carbon in the powdered form are used, practically all tastes and odors are removed from water by
a. absorbotion
b. polymerization
c. adsorbtion
d. oxidation
c. adsorbtion
activated carbon ADSORBS the tastes and odors
It has been estimated that waterborne diseases worldwide accounts for…
250 million illnesses per year
Leaching from a garbage dump has been found to pollute wells how far away
2,000 feet away
Residential cespool and septic tank soil absorbtion system discharge…
400 million gallons of sewage into the ground each year
Alkalinity of water is desirable at levels of
a. 0 to 30 mg/l
b. 0 to 500 mg/l
c. 30 to 100 mg/l
d. 0 to 5 mg/l
c. 30 to 100 mg/l
Which of the following is not included in the nine contaminate groups?
a. mircroorganisms
b. volatile organic chemicals
c. turbidity
d. lead and copper
e. nitrate and nitrite
a. microorganisms
What is the required annular seal depth for a domestic water supply well?
20 ft
Choose which protozoa are commonly found in untreated surface water?
a. Giardia
b. Crypto
c. Legionella
d. E. Coli
e. a and b
f. c and d
e. a and b
Giardia and crypto
but also Naegleria, Entemoeba histolytica, Toxoplasma gondii
What are some waterborne bacterias?
- Psuedomonas aeruginosa
- Legionella pneumophila
- Salmonella typhi
- Salmonella paratyphi
- Campylobacter jejuni
- Shigella
- Vibrio cholera
- E. coli 0157:H7
What are some waterborne viruses?
- Enteroviruses
- Rotavirus
- Norwalk virus
- Hepatitis A
What is the MCL for Arsenic?
0.01 mg/l
What is the MCL for Copper?
1.3 mg/l
What is the MCL for Lead?
0.015 mg/l
1 mg/l = __ ppm ?
1 mg/l = 1 ppm
1 ppm = __ ppb ?
1 ppm = 1000 ppb
1 ppb = __ ppm ?
1 ppb = 0.001ppm
0.001 x 1000 = 1
What is the MCL for Gross Alpha?
15 pCi/l
A 4-Log removal system must remove
a. 90% of pathogens
b. 99% of pathogens
c. 99.9% of pathogens
d. 99.99% of pathogens
d. 99.99% of pathogens
A BAT for Uranium is
a. Ion exchange (IX)
b. Granular activated carbon (GAC)
c. Oxidation
d. The Manhattan Project
a. Ion exchange (IX)
Air stripping is a type of treatment used to remove
a. TTHMs
b. Arsenic
c. Nitrate
d. Uranium
a. TTHMs
The number of bacT samples that a CWS must collect is based upon
a. Service area in acres
b. Population
c. Amount of water produced in MGD
d. Number of service connections
e. a and c
f. b and d
f. b and d
- What is the required annular seal depth for a public water supply well?
a. 1 year
b. 55 feet
c. 20 feet
d. 50 feet
d. 50 feet
What is the minimum pressure that a PWS is required to meet?
a. 20psi
b. 15psi
c. 5psi
d. PSI Miami
a. 20psi
Which is considered a BAT for Nitrate removal?
a. Activated Alumina
b. Ketogenesis
c. Reverse Osmosis (RO)
d. Air Stripping
c. Reverse Osmosis (RO)
What are two major groups of Disinfectant Byproducts?
a. Coliforms
b. Halo Acetic Acids
c. Patrites
d. Trihalomethanes
e. a and b
f. b and d
f. b and d
What is the MCL for Arsenic?
a. 10ppm
b. 10ppb
c. 5ppm
d. 5ppb
b. 10ppb
Arsenic mcl is 0.01 ppm,
0.01 x 1000 = 10 ppb
The disinfection ability of chlorine is affected most by
a. BOD
b. temperature
c. hydrogen ion concentration
d. dissolved oxygen
c. hydrogen ion concentration
What are the three forms of Alkalinity?
bicarbonate
hydroxide
hypochlorite
The main function of a sand filter is to:
remove suspended solids
According to the SDWA, the minimum number of water samples which must be submitted for bacteriological analysis for a public water supply depends upon the:
a. daily population served
b. population served
c. areas of the raw water supply
d. amount of water treated
b. population served
If hard water is softened by the ion exchange method, which one of the following will increase?
a. dissolved oxygen
b. iron
c. p1-1
d. sodium
d. sodium
Aearation is advantageous in the treatment of water containing:
dissolved iron and maganese
The pH of a solution in which the apparent hydrogen ion concentration is equal to 10-8 moles per liter is …
8
What is used for coagulation?
aluminum sulfate
