REHS Exam Ch.1- Water questions well
answers graded A+ updated
Which of the following soil conditions is the most favorable for removal of viruses? - correct
answer ✔✔Fine loamy sand over course sand & gravel
Which of the following organisms are most resistant to unfavorable env. conditions & indicates
past or possibly intermittent pollution? - correct answer ✔✔Clostridium sporulates
Which of the following wells is considered the most dependable source of water & is less likely
to become contaminated? - correct answer ✔✔Drilled wells
Which of the following is NOT considered a satisfactory solution to the problem of chem.
contamination in well systems? - correct answer ✔✔Boiling the water
Which of the following chems is the most widely used to destory microorgs? - correct answer
✔✔Chlorine
Which of the following is the best of backflow control? - correct answer ✔✔Air gap
Microscopic photosyn. plants of the simplest forms, having neither roots, stems no leaves, that
are associated with taste & odor, filter clogging and other water problems are known as: -
correct answer ✔✔Algae
Control of infectious, intestinal diseases of humans requires: - correct answer ✔✔Provisions of
safe water supplies, proper waste disposal & personal hygeine
,Drinking water standards generally specify that a water is safe provided that testing in a
speicifed manner does no reveal more than an avg of: - correct answer ✔✔1 (+) sample out of
40 taken
What does it mean when a body of water has a high JTU? - correct answer ✔✔it has high
turbidity
The presence of which of the following is the most easily id by lab analysis in water
contaminated by feces? - correct answer ✔✔coliform
Nephelometric Turbidity Unit (NTU) are most commonly used to - correct answer ✔✔determine
turbidity
The safe distance between a well and waste disposal system is dependent on - correct answer
✔✔chem, phyiscal and bio processes
What is the first step in eval the safety of a potential water system? - correct answer ✔✔a
detailed sanitary survey of the water supply
What are examples of groundwater systems? - correct answer ✔✔dug, bored, driven, drill wells,
rock, sand or earth springs, infiltration galleries
What are the causes of hardness? - correct answer ✔✔dissolved calcium * mag bicarbs, sulfates
and chlorides
What is desalination? - correct answer ✔✔The conversion of seawater or brackish water to
fresh water.
The quality of surface water depends on - correct answer ✔✔the watershed area drained, land
use, location & source of pollution& the natural agencies of purification
, Which of the following is NOT commonly used for disinfection of water? - correct answer
✔✔silver nitrate
Hydro pneumatic or pressure-tank water systems are suitable for: - correct answer ✔✔small
comm., housing dev, private homes, and estates, camps, food service ops and hotels
The hydro pneumatic tank typically contains ________ of its volume as water. - correct answer
✔✔20%
Water containing nitrates generally indicates - correct answer ✔✔evidence of pollution
Diatomaceous earth filters - correct answer ✔✔should be augmented by chlorination
Hydrogen sulfide can be fatal at exposures of - correct answer ✔✔300ppm
The most practical method for removing nitrates from water is - correct answer ✔✔ion
exchange
Which of the following is NOT a practical method for removal of cadium? - correct answer
✔✔Reverse osmosis
Back-siphonage may be prevented by all of the following methods except - correct answer
✔✔barometric loop ( those used include air gaps,vac breakers, backpressure units)
Of the following, which is not a variable to be considered when deciding upon a safe distance
between a well & sewage disposal system? - correct answer ✔✔The # of indv. utilizing the well
answers graded A+ updated
Which of the following soil conditions is the most favorable for removal of viruses? - correct
answer ✔✔Fine loamy sand over course sand & gravel
Which of the following organisms are most resistant to unfavorable env. conditions & indicates
past or possibly intermittent pollution? - correct answer ✔✔Clostridium sporulates
Which of the following wells is considered the most dependable source of water & is less likely
to become contaminated? - correct answer ✔✔Drilled wells
Which of the following is NOT considered a satisfactory solution to the problem of chem.
contamination in well systems? - correct answer ✔✔Boiling the water
Which of the following chems is the most widely used to destory microorgs? - correct answer
✔✔Chlorine
Which of the following is the best of backflow control? - correct answer ✔✔Air gap
Microscopic photosyn. plants of the simplest forms, having neither roots, stems no leaves, that
are associated with taste & odor, filter clogging and other water problems are known as: -
correct answer ✔✔Algae
Control of infectious, intestinal diseases of humans requires: - correct answer ✔✔Provisions of
safe water supplies, proper waste disposal & personal hygeine
,Drinking water standards generally specify that a water is safe provided that testing in a
speicifed manner does no reveal more than an avg of: - correct answer ✔✔1 (+) sample out of
40 taken
What does it mean when a body of water has a high JTU? - correct answer ✔✔it has high
turbidity
The presence of which of the following is the most easily id by lab analysis in water
contaminated by feces? - correct answer ✔✔coliform
Nephelometric Turbidity Unit (NTU) are most commonly used to - correct answer ✔✔determine
turbidity
The safe distance between a well and waste disposal system is dependent on - correct answer
✔✔chem, phyiscal and bio processes
What is the first step in eval the safety of a potential water system? - correct answer ✔✔a
detailed sanitary survey of the water supply
What are examples of groundwater systems? - correct answer ✔✔dug, bored, driven, drill wells,
rock, sand or earth springs, infiltration galleries
What are the causes of hardness? - correct answer ✔✔dissolved calcium * mag bicarbs, sulfates
and chlorides
What is desalination? - correct answer ✔✔The conversion of seawater or brackish water to
fresh water.
The quality of surface water depends on - correct answer ✔✔the watershed area drained, land
use, location & source of pollution& the natural agencies of purification
, Which of the following is NOT commonly used for disinfection of water? - correct answer
✔✔silver nitrate
Hydro pneumatic or pressure-tank water systems are suitable for: - correct answer ✔✔small
comm., housing dev, private homes, and estates, camps, food service ops and hotels
The hydro pneumatic tank typically contains ________ of its volume as water. - correct answer
✔✔20%
Water containing nitrates generally indicates - correct answer ✔✔evidence of pollution
Diatomaceous earth filters - correct answer ✔✔should be augmented by chlorination
Hydrogen sulfide can be fatal at exposures of - correct answer ✔✔300ppm
The most practical method for removing nitrates from water is - correct answer ✔✔ion
exchange
Which of the following is NOT a practical method for removal of cadium? - correct answer
✔✔Reverse osmosis
Back-siphonage may be prevented by all of the following methods except - correct answer
✔✔barometric loop ( those used include air gaps,vac breakers, backpressure units)
Of the following, which is not a variable to be considered when deciding upon a safe distance
between a well & sewage disposal system? - correct answer ✔✔The # of indv. utilizing the well
