Alabama Water Treatment Operator
questions and answers graded A+
updated
1. Two of the undesirable characteristics of a water that would cause a water to be corrosive
includes:
a. High pH and alkalinity
b. No dissolved oxygen and moderate hardness
c. Low temperature and low velocity
d. High carbon dioxide and low pH
e. No hydrogen sulfides and moderate alkalinity - correct answer ✔✔d. High carbon dioxide and
low pH
2. If a cross-connection is discovered in connection with a hazardous chemical, what is the best
protection to
install?
a. Double check valve assembly
b. Automatic switch over unit
c. Rotating coupling
d. Air gap or RP device - correct answer ✔✔d. Air gap or RP device
3. The chemical used in making a free residual test is:
a. Phenolphthalain
,b. Orthotolodine
c. Sodium arsenite
d. N, N-diethyl-phenylene-Diamine (DPD)
e. None of the above - correct answer ✔✔d. N, N-diethyl-phenylene-Diamine (DPD)
4. A 3 MGD well operating an average of 2l hours a day. The rate of flow is approximately:
a. 1,440 gpm
b. 2,400 gpm
c. 3,000 gpm
d. 2,100 gpm - correct answer ✔✔b. 2,400 gpm
5. The static pressure in a pipeline is 20 psi. How much head creates that pressure?
a. 139feet
b. 26 feet
c. 260 feet
d. 46 feet - correct answer ✔✔d. 46 feet
6. Jack lives in Wipple Will Holler and the pressure at his house is 50 psi and his friend Billy
Frank lives 3 blocks up at a 100 feet higher elevation. The tank is located at the highest point.
What is the pressure at Billy Frank's house?
a. 43 psi
b. 25 psi
c. 6.7 psi
d. 93 psi - correct answer ✔✔c. 6.7 psi
,100 ft / 2.31 = 43.3
50 psi - 43.3 = 6.7 psi
Note: Higher Elevation will have lower psi
7. The overflow elevation of the 10,000 gallon elevated tank is 173 feet from ground level. The
static pressure at ground level is psi.
a. 20 psi
b. 34 psi
c. 64 psi
d. 75 psi - correct answer ✔✔d. 75 psi
173 ft / 2.31 = 74.89 psi
8. After installing 1 mile of 24-inch PVC pipe (which contains approximately 124,344 gallons of
water) you plan to disinfect the entire line. How many pounds of HTH (70% available chlorine)
will be needed to
provide the proper concentration to disinfect this new water main?
a. 19.45 pounds
b. 36.3 pounds
c. 51.8 pounds
d. 74.0 pounds - correct answer ✔✔d. 74.0 pounds
, 124,344 gal / 1,000,000 = .124 mdg
.124 (8.34) 50mg/l (if dose is not given use 50 mg/l)
51.8 / .70 = 74.1 pounds
9. The flow in mains can be expressed in terms of:
a. Cubic feet per second
b. Million gallons per day
c. Gallons per minute
d. All of the above - correct answer ✔✔d. All of the above
10. The volume of water necessary to fill a 1,000 foot long section of 12-inch inside diameter
circular pipe is about:
a. 5,888 gallons
b. 7, 700 gallons
c. 2,000 gallons
d. 785 gallons - correct answer ✔✔a. 5,888 gallons
12 inch = 1 ft
1 x 1 x .785 x 1,000 = 785 cf x 7.48 cf /gal = 5871.8 closest to 5,888 gal
11. Staining problems from iron occur most in _____ water.
questions and answers graded A+
updated
1. Two of the undesirable characteristics of a water that would cause a water to be corrosive
includes:
a. High pH and alkalinity
b. No dissolved oxygen and moderate hardness
c. Low temperature and low velocity
d. High carbon dioxide and low pH
e. No hydrogen sulfides and moderate alkalinity - correct answer ✔✔d. High carbon dioxide and
low pH
2. If a cross-connection is discovered in connection with a hazardous chemical, what is the best
protection to
install?
a. Double check valve assembly
b. Automatic switch over unit
c. Rotating coupling
d. Air gap or RP device - correct answer ✔✔d. Air gap or RP device
3. The chemical used in making a free residual test is:
a. Phenolphthalain
,b. Orthotolodine
c. Sodium arsenite
d. N, N-diethyl-phenylene-Diamine (DPD)
e. None of the above - correct answer ✔✔d. N, N-diethyl-phenylene-Diamine (DPD)
4. A 3 MGD well operating an average of 2l hours a day. The rate of flow is approximately:
a. 1,440 gpm
b. 2,400 gpm
c. 3,000 gpm
d. 2,100 gpm - correct answer ✔✔b. 2,400 gpm
5. The static pressure in a pipeline is 20 psi. How much head creates that pressure?
a. 139feet
b. 26 feet
c. 260 feet
d. 46 feet - correct answer ✔✔d. 46 feet
6. Jack lives in Wipple Will Holler and the pressure at his house is 50 psi and his friend Billy
Frank lives 3 blocks up at a 100 feet higher elevation. The tank is located at the highest point.
What is the pressure at Billy Frank's house?
a. 43 psi
b. 25 psi
c. 6.7 psi
d. 93 psi - correct answer ✔✔c. 6.7 psi
,100 ft / 2.31 = 43.3
50 psi - 43.3 = 6.7 psi
Note: Higher Elevation will have lower psi
7. The overflow elevation of the 10,000 gallon elevated tank is 173 feet from ground level. The
static pressure at ground level is psi.
a. 20 psi
b. 34 psi
c. 64 psi
d. 75 psi - correct answer ✔✔d. 75 psi
173 ft / 2.31 = 74.89 psi
8. After installing 1 mile of 24-inch PVC pipe (which contains approximately 124,344 gallons of
water) you plan to disinfect the entire line. How many pounds of HTH (70% available chlorine)
will be needed to
provide the proper concentration to disinfect this new water main?
a. 19.45 pounds
b. 36.3 pounds
c. 51.8 pounds
d. 74.0 pounds - correct answer ✔✔d. 74.0 pounds
, 124,344 gal / 1,000,000 = .124 mdg
.124 (8.34) 50mg/l (if dose is not given use 50 mg/l)
51.8 / .70 = 74.1 pounds
9. The flow in mains can be expressed in terms of:
a. Cubic feet per second
b. Million gallons per day
c. Gallons per minute
d. All of the above - correct answer ✔✔d. All of the above
10. The volume of water necessary to fill a 1,000 foot long section of 12-inch inside diameter
circular pipe is about:
a. 5,888 gallons
b. 7, 700 gallons
c. 2,000 gallons
d. 785 gallons - correct answer ✔✔a. 5,888 gallons
12 inch = 1 ft
1 x 1 x .785 x 1,000 = 785 cf x 7.48 cf /gal = 5871.8 closest to 5,888 gal
11. Staining problems from iron occur most in _____ water.
