Water Operator Class D Study Guide
Comprehensive Resource To Help You Ace 2026-2027
Includes Frequently Tested Questions With ELABORATED
100% Correct COMPLETE SOLUTIONS
Guaranteed Pass First Attempt!!
Current Update!!
1. List 5 characteristics of Hydrogen Sulfide - Correct Answer: heavier than
air; colorless; flammable; toxic; has a rotten egg odor
2. Excessive nitrates in drinking water can cause - Correct Answer: blue
baby syndrome in infants
3. Excessive amounts of fluoride may cause - Correct Answer:
mottling/staining of teeth
4. byproducts of chlorination - Correct Answer: Trihalomethanes THMs;
Haloacetic Acids HAAs
5. Trihalomethanes and Haloacetic Acids may cause problems with (4 health
related items) - Correct Answer: the liver; kidneys; central nervous
systems; increase cancer risks
,6. What is the Action level for Copper? (by the Lead and Copper rule) -
Correct Answer: 1.3 mg/L
7. What is the Action level for Lead? (by the Lead and Copper rule) -
Correct Answer: .015
8. Turbidity limits - Correct Answer: less than or equal to .3 NTU
9. What is the acceptable Fluoride range in water? - Correct Answer: .7 to
1.0 mg/L
10.Nitrates Limits - Correct Answer: less than or equal to 20mg/L as
nitrogen
11.Dissolved solids limits - Correct Answer: less than or equal to 1000 mg/L
12.Taste and Color Limits - Correct Answer: less than or equal to 15 units
13.Aquifer - Correct Answer: underground water-bearing formation
yielding useful quantities of water
14.The quantity of water that a formation yields depends on - Correct
Answer: the depth, thickness, drawdown and permeability of the formation
,15.What are 2 problems caused by over-pumping include - Correct Answer:
falling water levels; subsidence
16.subsidence - Correct Answer: sinking of the land
17.the purpose of the well casing and cementing is to - Correct Answer:
protect the well from collapse and surface contamination
18.The purpose of the well screen is to - Correct Answer: reduce/keep sand
out of the well
19.the most important feature of the well screen is - Correct Answer: the
size of the openings (mesh size)
20.A screen's mesh size is determined by 3 things. What are they? - Correct
Answer: size of the aquifer material; size of the gravel in the gravel pack;
type of well development
21.Gravel pack - Correct Answer: Fine gravel placed around the well screen
22.The purpose of a well's gravel pack is to - Correct Answer: reduce
pumping sand
23.Well Vent - Correct Answer: vacuum breaker
, 24.The Purpose of a well vent - Correct Answer: to allow the casing to
breathe as water levels change when the pump cycles
25.Name 2 problems that vacuums in wells can cause - Correct Answer:
drawing of contaminants into the well; restriction of the free flow of water
to the well pump
26.Public wells must be provided with 4 things. What are they? - Correct
Answer: concrete sealing block; meter; screened vent; sampling faucet
27.Contamination types allowed INSIDE/WITHIN 50 feet of a well - Correct
Answer: None
28.Livestock must be this many feet away from a well - Correct Answer: 50
29.Storm Sewers must be this many feet away from a well - Correct
Answer: 50
30.Septic Tanks must be this many feet away from a well - Correct Answer:
50
31.Tile or Concrete Sewers must be this many feet away from a well -
Correct Answer: 50
Comprehensive Resource To Help You Ace 2026-2027
Includes Frequently Tested Questions With ELABORATED
100% Correct COMPLETE SOLUTIONS
Guaranteed Pass First Attempt!!
Current Update!!
1. List 5 characteristics of Hydrogen Sulfide - Correct Answer: heavier than
air; colorless; flammable; toxic; has a rotten egg odor
2. Excessive nitrates in drinking water can cause - Correct Answer: blue
baby syndrome in infants
3. Excessive amounts of fluoride may cause - Correct Answer:
mottling/staining of teeth
4. byproducts of chlorination - Correct Answer: Trihalomethanes THMs;
Haloacetic Acids HAAs
5. Trihalomethanes and Haloacetic Acids may cause problems with (4 health
related items) - Correct Answer: the liver; kidneys; central nervous
systems; increase cancer risks
,6. What is the Action level for Copper? (by the Lead and Copper rule) -
Correct Answer: 1.3 mg/L
7. What is the Action level for Lead? (by the Lead and Copper rule) -
Correct Answer: .015
8. Turbidity limits - Correct Answer: less than or equal to .3 NTU
9. What is the acceptable Fluoride range in water? - Correct Answer: .7 to
1.0 mg/L
10.Nitrates Limits - Correct Answer: less than or equal to 20mg/L as
nitrogen
11.Dissolved solids limits - Correct Answer: less than or equal to 1000 mg/L
12.Taste and Color Limits - Correct Answer: less than or equal to 15 units
13.Aquifer - Correct Answer: underground water-bearing formation
yielding useful quantities of water
14.The quantity of water that a formation yields depends on - Correct
Answer: the depth, thickness, drawdown and permeability of the formation
,15.What are 2 problems caused by over-pumping include - Correct Answer:
falling water levels; subsidence
16.subsidence - Correct Answer: sinking of the land
17.the purpose of the well casing and cementing is to - Correct Answer:
protect the well from collapse and surface contamination
18.The purpose of the well screen is to - Correct Answer: reduce/keep sand
out of the well
19.the most important feature of the well screen is - Correct Answer: the
size of the openings (mesh size)
20.A screen's mesh size is determined by 3 things. What are they? - Correct
Answer: size of the aquifer material; size of the gravel in the gravel pack;
type of well development
21.Gravel pack - Correct Answer: Fine gravel placed around the well screen
22.The purpose of a well's gravel pack is to - Correct Answer: reduce
pumping sand
23.Well Vent - Correct Answer: vacuum breaker
, 24.The Purpose of a well vent - Correct Answer: to allow the casing to
breathe as water levels change when the pump cycles
25.Name 2 problems that vacuums in wells can cause - Correct Answer:
drawing of contaminants into the well; restriction of the free flow of water
to the well pump
26.Public wells must be provided with 4 things. What are they? - Correct
Answer: concrete sealing block; meter; screened vent; sampling faucet
27.Contamination types allowed INSIDE/WITHIN 50 feet of a well - Correct
Answer: None
28.Livestock must be this many feet away from a well - Correct Answer: 50
29.Storm Sewers must be this many feet away from a well - Correct
Answer: 50
30.Septic Tanks must be this many feet away from a well - Correct Answer:
50
31.Tile or Concrete Sewers must be this many feet away from a well -
Correct Answer: 50
