Water Treatment Class D (practice exam
#3) Q&A’s 100% Verified Correct
What is the criteria for a community water system? - ANS ✔ - Has at least 15 service connections used
by all year residents, or regularly serves at least 25 all year residents
What is the acceptable limit of copper in drinking water? - ANS ✔ - 1.3 mg/L
Which type of reservoir is rich in nutrients? - ANS ✔ - eutrophic
What is a mechanical seal? - ANS ✔ - Metallic flat surfaces used to minimize leakage around the pump
shaft.
What is a confined aquifer? - ANS ✔ - An aquifer that is bounded above and below by confining beds
Which of the following best describes pumping water level in a well? - ANS ✔ - Upper surface of the
groundwater that is being pumped
What is the name of the deepest layer of a reservoir under thermal stratification? - ANS ✔ -
hypolimnion
What is the health effect of consuming water with high levels of copper? - ANS ✔ - Stomach and
intestinal distress such as nausea, vomiting, diarrhea and stomach cramps
Which of the following best describes a turbine pump? - ANS ✔ - A centrifugal pump that is mainly
used to pump water from wells
What is typically used to clean the sludge on the bottom of a rectangular clarifier? - ANS ✔ - Chain
and flight collectors
, Water Treatment Class D (practice exam
#3) Q&A’s 100% Verified Correct
How often should preventative maintenance be performed on equipment? - ANS ✔ - Use
manufacturer's recommendation.
What is CT? - ANS ✔ - Contact time x chlorine residual concentration
What is absorption? - ANS ✔ - Constituent is sucked in
What is the purpose of a check valve? - ANS ✔ - Allows water to flow in one direction, and prevents
reverse flow
What would happen to the pH of water if lime is added? - ANS ✔ - increases pH
What is the term used to describe groundwater that flows naturally from the ground? - ANS ✔ - spring
Once thermal stratification occurs in the middle and lower zones of a reservoir, what type of problem
occurs in these layers? - ANS ✔ - Depletion of total dissolved oxygen
What is the most critical problem that may be encountered when entering a confined space? - ANS ✔
- Oxygen deficiency and toxic gas
Which of the following is a settle able solid? - ANS ✔ - Sand
Which of the following is not a commonly used coagulant? - ANS ✔ - sodium hypochlorite
What is the purpose of a coagulant aid? - ANS ✔ - Add density to slow-settling flocs and add toughness
to the flocs.
What is the purpose of coagulant (not coagulant aid)? - ANS ✔ - Neutralize electrical charge.
#3) Q&A’s 100% Verified Correct
What is the criteria for a community water system? - ANS ✔ - Has at least 15 service connections used
by all year residents, or regularly serves at least 25 all year residents
What is the acceptable limit of copper in drinking water? - ANS ✔ - 1.3 mg/L
Which type of reservoir is rich in nutrients? - ANS ✔ - eutrophic
What is a mechanical seal? - ANS ✔ - Metallic flat surfaces used to minimize leakage around the pump
shaft.
What is a confined aquifer? - ANS ✔ - An aquifer that is bounded above and below by confining beds
Which of the following best describes pumping water level in a well? - ANS ✔ - Upper surface of the
groundwater that is being pumped
What is the name of the deepest layer of a reservoir under thermal stratification? - ANS ✔ -
hypolimnion
What is the health effect of consuming water with high levels of copper? - ANS ✔ - Stomach and
intestinal distress such as nausea, vomiting, diarrhea and stomach cramps
Which of the following best describes a turbine pump? - ANS ✔ - A centrifugal pump that is mainly
used to pump water from wells
What is typically used to clean the sludge on the bottom of a rectangular clarifier? - ANS ✔ - Chain
and flight collectors
, Water Treatment Class D (practice exam
#3) Q&A’s 100% Verified Correct
How often should preventative maintenance be performed on equipment? - ANS ✔ - Use
manufacturer's recommendation.
What is CT? - ANS ✔ - Contact time x chlorine residual concentration
What is absorption? - ANS ✔ - Constituent is sucked in
What is the purpose of a check valve? - ANS ✔ - Allows water to flow in one direction, and prevents
reverse flow
What would happen to the pH of water if lime is added? - ANS ✔ - increases pH
What is the term used to describe groundwater that flows naturally from the ground? - ANS ✔ - spring
Once thermal stratification occurs in the middle and lower zones of a reservoir, what type of problem
occurs in these layers? - ANS ✔ - Depletion of total dissolved oxygen
What is the most critical problem that may be encountered when entering a confined space? - ANS ✔
- Oxygen deficiency and toxic gas
Which of the following is a settle able solid? - ANS ✔ - Sand
Which of the following is not a commonly used coagulant? - ANS ✔ - sodium hypochlorite
What is the purpose of a coagulant aid? - ANS ✔ - Add density to slow-settling flocs and add toughness
to the flocs.
What is the purpose of coagulant (not coagulant aid)? - ANS ✔ - Neutralize electrical charge.
