Wastewater Practice Exam 2025/2026(Questions with
100% Verified Correct Answers) for Guaranteed pass.
WASTE WATER TREATMENT
PRACTICE EXAM- TOUGHEST AND MOST TESTED QUESTIONS
According to FDEP chapter 62-600.440 (4) (b) FAC, basic level disinfection is described as: -
ANSWER-A chlorine residual of 0.5 mg/L for 15 minutes at peak hourly flow
FDEP chapter 62-604.550 (a) FAC, requires a wastewater spill shall be verbally reported to the state
warning point no later than: - ANSWER-24hrs from discovery
What is the 'rule of thumb' regarding pump packing? - ANSWER-Never put rings of new packing over
the old packing
According to FDEP chapter 62-60, FAC, a composite sample shall be used for which test? - ANSWER-
Effluent CBOD
Chlorine residual can be measured in several ways, including the use of DPD reagent,
spectrophotometers and iodometric titration. Which of the following is also an approved method? -
ANSWER-Amperometric Titration
Chapter 62-601, Domestic wastewater treatment plant monitoring, states that on-site tests for total
residual chlorine, pH, and _______ can be performed under the direction of a certified operator: -
ANSWER-Dissolved Oxygen(DO)
Starting this type of pump against a closed valve can cause major damage to the pump, pump piping,
the operator, or all three - ANSWER-Positive displacement pump
These types of samples may be used for CBOD5 and nutrients at flows less than 100,000 GPD,
according to chapter 62-601 - ANSWER-Grab samples
According to FDEP chapter 62-602, drinking water and wastewater treatment plant operators, duties of
operators includes reporting to the permittee and the department, as soon as possible, but within 24hrs:
- ANSWER-Any major interruption of service
What could cause a centrifugal above ground pump to be noisy while running - ANSWER-Debris
caught in the impeller housing
According to FDEP chapter 62-601 FAC, Domestic wastewater treatment plant monitoring, discharge
monitoring reports (DMRs) for the previous month must be submitted to the department by the
____________ day of the current month? - ANSWER-28th day
1
, FDEP chapter 62-600 FC, domestic wastewater facilities, states that all treatment plants shall
be____________ - ANSWER-Fenced
As the operator of a primary clarifier, you notice a black and odorous septic wastewater leaving the
clarifier. What is the probable cause? - ANSWER-Improper sludge removal
A fire has started in the maintenance shop due to an ignition of petroleum oil. Which type of fire
extinguisher should NOT be used to fight the fire? - ANSWER-Pressurized water
Chlorine gas is how many times heavier than air - ANSWER-2.5
The combination of methane and ____________ can be very combustible - ANSWER-Oxygen
Plant effluent coliform count fails to meet the required standards for disinfection. Chlorine residual is
normal. Disinfectant supplies ARE NOT a problem. What is the probable cause? - ANSWER-Contact
time too short
A fixed sample is: - ANSWER-A sample purposely spiked by the lab technician for QA/QC
According to FDEP chapter 62-602 FAC, an operator could have his license permanently revoked for: -
ANSWER-Falsified or misrepresented reports, logs, or lab sheets
What process do the bacteria perform in the stabilization(re-aeration) tank in the contact stabilization
process? - ANSWER-Absorption and digestion of the waste material they collected
A screenings dumpster at the head works of the treatment plant is full at the end of the day. The
dumpster is 6ft tall, 10ft long, and 8ft wide. How many cubic yards of screenings must be disposed of
in a 30 day month? - ANSWER-533 (6 x 10 x 8 = 480) (480 /27 = 17.7) (17.7 x 30 = 533)
When properly adjusted, the rope packing on a centrifugal pump is designed to leak how much? -
ANSWER-One drip per second
A confined space is defined as having a space large enough to bodily enter and perform work, has
limited entry and egress and is ___________? - ANSWER-Not designed for continuous occupancy
You noticed that your bearings are excessively hot on a pump, why? - ANSWER-Over lubrication
Where can you gain access for collection system maintenance? - ANSWER-Man hole
Low DO and nutrient deficiency will promote the growth of _________? - ANSWER-Filamentous
bacteria
When charging a lead-acid type battery for a composite sampler, what dangerous gas could be
produced? - ANSWER-Hydrogen
What is the best method in dealing with a chemical spill? - ANSWER-Contain and clean up
2
100% Verified Correct Answers) for Guaranteed pass.
WASTE WATER TREATMENT
PRACTICE EXAM- TOUGHEST AND MOST TESTED QUESTIONS
According to FDEP chapter 62-600.440 (4) (b) FAC, basic level disinfection is described as: -
ANSWER-A chlorine residual of 0.5 mg/L for 15 minutes at peak hourly flow
FDEP chapter 62-604.550 (a) FAC, requires a wastewater spill shall be verbally reported to the state
warning point no later than: - ANSWER-24hrs from discovery
What is the 'rule of thumb' regarding pump packing? - ANSWER-Never put rings of new packing over
the old packing
According to FDEP chapter 62-60, FAC, a composite sample shall be used for which test? - ANSWER-
Effluent CBOD
Chlorine residual can be measured in several ways, including the use of DPD reagent,
spectrophotometers and iodometric titration. Which of the following is also an approved method? -
ANSWER-Amperometric Titration
Chapter 62-601, Domestic wastewater treatment plant monitoring, states that on-site tests for total
residual chlorine, pH, and _______ can be performed under the direction of a certified operator: -
ANSWER-Dissolved Oxygen(DO)
Starting this type of pump against a closed valve can cause major damage to the pump, pump piping,
the operator, or all three - ANSWER-Positive displacement pump
These types of samples may be used for CBOD5 and nutrients at flows less than 100,000 GPD,
according to chapter 62-601 - ANSWER-Grab samples
According to FDEP chapter 62-602, drinking water and wastewater treatment plant operators, duties of
operators includes reporting to the permittee and the department, as soon as possible, but within 24hrs:
- ANSWER-Any major interruption of service
What could cause a centrifugal above ground pump to be noisy while running - ANSWER-Debris
caught in the impeller housing
According to FDEP chapter 62-601 FAC, Domestic wastewater treatment plant monitoring, discharge
monitoring reports (DMRs) for the previous month must be submitted to the department by the
____________ day of the current month? - ANSWER-28th day
1
, FDEP chapter 62-600 FC, domestic wastewater facilities, states that all treatment plants shall
be____________ - ANSWER-Fenced
As the operator of a primary clarifier, you notice a black and odorous septic wastewater leaving the
clarifier. What is the probable cause? - ANSWER-Improper sludge removal
A fire has started in the maintenance shop due to an ignition of petroleum oil. Which type of fire
extinguisher should NOT be used to fight the fire? - ANSWER-Pressurized water
Chlorine gas is how many times heavier than air - ANSWER-2.5
The combination of methane and ____________ can be very combustible - ANSWER-Oxygen
Plant effluent coliform count fails to meet the required standards for disinfection. Chlorine residual is
normal. Disinfectant supplies ARE NOT a problem. What is the probable cause? - ANSWER-Contact
time too short
A fixed sample is: - ANSWER-A sample purposely spiked by the lab technician for QA/QC
According to FDEP chapter 62-602 FAC, an operator could have his license permanently revoked for: -
ANSWER-Falsified or misrepresented reports, logs, or lab sheets
What process do the bacteria perform in the stabilization(re-aeration) tank in the contact stabilization
process? - ANSWER-Absorption and digestion of the waste material they collected
A screenings dumpster at the head works of the treatment plant is full at the end of the day. The
dumpster is 6ft tall, 10ft long, and 8ft wide. How many cubic yards of screenings must be disposed of
in a 30 day month? - ANSWER-533 (6 x 10 x 8 = 480) (480 /27 = 17.7) (17.7 x 30 = 533)
When properly adjusted, the rope packing on a centrifugal pump is designed to leak how much? -
ANSWER-One drip per second
A confined space is defined as having a space large enough to bodily enter and perform work, has
limited entry and egress and is ___________? - ANSWER-Not designed for continuous occupancy
You noticed that your bearings are excessively hot on a pump, why? - ANSWER-Over lubrication
Where can you gain access for collection system maintenance? - ANSWER-Man hole
Low DO and nutrient deficiency will promote the growth of _________? - ANSWER-Filamentous
bacteria
When charging a lead-acid type battery for a composite sampler, what dangerous gas could be
produced? - ANSWER-Hydrogen
What is the best method in dealing with a chemical spill? - ANSWER-Contain and clean up
2
