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Iowa Wastewater Operator Grade I Exam ACTUAL
VERIFIED EXAM COMPLETE QUESTIONS AND
CORRECT ANSWERS LATEST UPDATE THIS
YEAR.pdf||NEWEST EXAM!!!
Which agency sets standards on concentration levels of
harmful contaminants in drinking water? - Answer-USEPA
Explain the difference between the different tiers of
violations. Which one is the most serious? - Answer-Tier 1
is an acuty MCL violation requiring public notification
within 24 hrs. Tier 2 notification must occur within 30 days.
Tier 3 require notification within 1 year.
A positive E. coli test must be reported to the primacy
health agency within what period of time? - Answer-24
hours
How is the required number of monthly bacteriological
samples determined? - Answer-Population served
What is the action level for lead in first draw samples
taken from customer taps? - Answer-.015 mg/L
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A water system is designated a community public water
system if it serves how many homes? - Answer-15 or more
What authority provides specific water sampling
instructions? - Answer-the state primacy agency
According to the Lead and Copper Rule, what is the action
level for lead? - Answer-0.015 mg/L
Determine the detention time in hours for the following
water treatment system: Distribution pipe from water plant
to storage tank is 549 feet in length and 14 inches in
diameter. Storage tank averages 2,310,000 gallons of
water at any given time. Flow through system is 6.72 mgd.
- Answer-8.3 hours
divide daily flow by 24 hours in a day (280,000)
then divide 280,000 into tank capacity
If chlorine is being fed at a rate of 260lb/day for a flow rate
of 23cf/s, what should be the adjustment on the chlorinator
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when the flow rate is decreased to 16 cf/s if all other
parameters were to stay the same? - Answer-180lb/day
260/23=x/16
divide 260 by 23, then multiply that by 16
How many gallons of sodium hypochlorite solution that
contain 12.1% available chlorine are needed to disinfect a
1.5ft diameter pipeline that is 283 feet long, if the dosage
required is 50 mg/L? Assume the sodium hypochlorite is
9.92 lb/gallon. - Answer-1.3 gallons sodium hypochlorite
sodium HCl=[(mil gal)(dosage)(8.34)]/[%avail Cl2/100%]
A storage tank has a 60ft radius and averages 25.5ft in
water depth. Calculate the average detention time in hours
for this storage tank, if flow through the tank averages
2.91 mgd during the month in question. - Answer-17.8
hours
A 24in pipeline, 427ft long, was disinfected with calcium
hypochlorite tablets with 65% available chlorine.
Determine the chlorine dosage in mg/L, if 7lb of calcium
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hypochlorite was used. Assume that the hypochlorite is so
diluted that it weighs 8.34lb/gal. - Answer-54 mg/L
CaHCl(lb/day)= [(mgd)(dosage)(8.34)(100%)]/[%available
Cl2]
Head is measured in
a. absolute pressure
b. gauge pressure
c. feet
d. foot-pounds - Answer-c
A plat is
a. a map
b. a corrosion point on a pipe
c. an organelle found in some protozoans
d. a highly corrosive soil type - Answer-A
At which time of day is the age of the water stored in the
distribution system the highest?
a. Early morning
Iowa Wastewater Operator Grade I Exam ACTUAL
VERIFIED EXAM COMPLETE QUESTIONS AND
CORRECT ANSWERS LATEST UPDATE THIS
YEAR.pdf||NEWEST EXAM!!!
Which agency sets standards on concentration levels of
harmful contaminants in drinking water? - Answer-USEPA
Explain the difference between the different tiers of
violations. Which one is the most serious? - Answer-Tier 1
is an acuty MCL violation requiring public notification
within 24 hrs. Tier 2 notification must occur within 30 days.
Tier 3 require notification within 1 year.
A positive E. coli test must be reported to the primacy
health agency within what period of time? - Answer-24
hours
How is the required number of monthly bacteriological
samples determined? - Answer-Population served
What is the action level for lead in first draw samples
taken from customer taps? - Answer-.015 mg/L
,2|Page
A water system is designated a community public water
system if it serves how many homes? - Answer-15 or more
What authority provides specific water sampling
instructions? - Answer-the state primacy agency
According to the Lead and Copper Rule, what is the action
level for lead? - Answer-0.015 mg/L
Determine the detention time in hours for the following
water treatment system: Distribution pipe from water plant
to storage tank is 549 feet in length and 14 inches in
diameter. Storage tank averages 2,310,000 gallons of
water at any given time. Flow through system is 6.72 mgd.
- Answer-8.3 hours
divide daily flow by 24 hours in a day (280,000)
then divide 280,000 into tank capacity
If chlorine is being fed at a rate of 260lb/day for a flow rate
of 23cf/s, what should be the adjustment on the chlorinator
,3|Page
when the flow rate is decreased to 16 cf/s if all other
parameters were to stay the same? - Answer-180lb/day
260/23=x/16
divide 260 by 23, then multiply that by 16
How many gallons of sodium hypochlorite solution that
contain 12.1% available chlorine are needed to disinfect a
1.5ft diameter pipeline that is 283 feet long, if the dosage
required is 50 mg/L? Assume the sodium hypochlorite is
9.92 lb/gallon. - Answer-1.3 gallons sodium hypochlorite
sodium HCl=[(mil gal)(dosage)(8.34)]/[%avail Cl2/100%]
A storage tank has a 60ft radius and averages 25.5ft in
water depth. Calculate the average detention time in hours
for this storage tank, if flow through the tank averages
2.91 mgd during the month in question. - Answer-17.8
hours
A 24in pipeline, 427ft long, was disinfected with calcium
hypochlorite tablets with 65% available chlorine.
Determine the chlorine dosage in mg/L, if 7lb of calcium
, 4|Page
hypochlorite was used. Assume that the hypochlorite is so
diluted that it weighs 8.34lb/gal. - Answer-54 mg/L
CaHCl(lb/day)= [(mgd)(dosage)(8.34)(100%)]/[%available
Cl2]
Head is measured in
a. absolute pressure
b. gauge pressure
c. feet
d. foot-pounds - Answer-c
A plat is
a. a map
b. a corrosion point on a pipe
c. an organelle found in some protozoans
d. a highly corrosive soil type - Answer-A
At which time of day is the age of the water stored in the
distribution system the highest?
a. Early morning
