Wastewater Collection Systems Exam

Free Sample Exam

Questions: 78

Passing score: 50 / 78 (64.1%)

Answer every question, then submit the exam to see your result and any areas that may need additional study.

Question 1 of 78

Operators suspect a blockage between two manholes. The upstream wastewater level is rising quickly, atmospheric testing at the downstream manhole indicates hazardous conditions, and an overflow may occur soon. What is the BEST response?

Begin mechanical cleaning immediately from the downstream location and address the hazardous atmosphere and emergency notifications only if cleaning does not restore flow.

Address the blockage and overflow risk using the emergency procedure while preventing unprotected entry into the hazardous confined space.

Focus on containing a possible overflow and postpone all blockage-removal actions until the manhole atmosphere returns to normal without considering safe aboveground or bypass alternatives.

Have a worker enter the manhole with a portable gas detector and begin clearing the blockage before the complete confined-space entry and rescue requirements are established.

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Question 2 of 78

What is one of the most serious hazards associated with working in an unprotected excavation or trench?

The only trench hazard is exposure to sunlight.

Excavation prevents all underground utility damage.

The trench automatically increases sewer capacity.

A trench wall cave-in can bury or crush workers.

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Question 3 of 78

Before entering a permit-required confined space in a wastewater collection system, what is an essential safety action?

Assume the space is safe if another employee entered it safely last week.

Use odor alone to determine whether the space is safe.

Follow the required confined-space entry procedure and test the atmosphere before entry.

Enter first and test the atmosphere only if symptoms develop.

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Question 4 of 78

A flow meter at a lift station begins reporting values that are inconsistent with pump run times and wet-well level changes. What should the operator do?

Verify the flow measurement and inspect or calibrate the meter as appropriate.

Change the pump run-time records so they agree with the flow meter.

Assume the meter is always correct and ignore all other operating information.

Delete all flow records from the previous year.

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Question 5 of 78

Why must underground utilities be located before excavation for a sewer repair?

To determine the operator certification class.

To eliminate the need for trench protection.

To reduce the risk of striking another buried utility and creating a serious hazard or service interruption.

To calculate wastewater BOD.

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Question 6 of 78

Severe flooding is forecast to threaten access and electrical service to several critical lift stations. What is the BEST preparedness response?

Activate the emergency plan, prioritize critical facilities, verify backup resources and communications, and coordinate needed outside support before conditions deteriorate.

Wait until individual lift stations lose power before deciding which facilities and outside organizations require attention.

Focus only on normal preventive-maintenance schedules because emergency coordination should begin only after an overflow occurs.

Send personnel to every threatened station regardless of whether flooding would make access unsafe.

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Question 7 of 78

Who may make process control decisions for a regulated Pennsylvania wastewater system?

Any employee after completing one week of employment.

Only the system owner, whether certified or not.

An appropriately certified operator whose certification applies to the system.

Any contractor working near the system.

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Question 8 of 78

What are the two major functions of a typical combination sewer-cleaning truck?

High-pressure water cleaning and vacuum removal of wastewater and debris.

Wastewater disinfection and drinking water filtration.

Pipe manufacturing and asphalt paving.

Sludge digestion and laboratory analysis.

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Question 9 of 78

Maintenance records show repeated blockages in the same sewer segment even though the line is cleaned each time. What is the BEST next step?

Assume repeated blockages prove that the pipe is structurally perfect.

Investigate the recurring cause using maintenance history and appropriate inspection methods rather than relying only on repeated cleaning.

Continue the same emergency cleaning indefinitely without investigating the cause.

Delete the previous blockage records after each cleaning.

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Question 10 of 78

Why can tree roots entering a sewer through defective joints create recurring collection-system problems?

Root intrusion affects only drinking water systems.

Roots automatically seal every defective sewer joint.

Roots increase the internal pipe diameter.

Roots can restrict flow and trap additional solids and debris, causing recurring stoppages.

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Question 11 of 78

A sanitary sewer overflow occurs and is stopped after a blockage is removed. What is the BEST administrative practice after the immediate response?

Wait until the final overflow volume and exact cause are known before beginning any required notification process.

Record the blockage and repair but omit the overflow because the collection system returned to normal operation during the same shift.

Document the event and follow the applicable notification and reporting requirements even though the overflow has stopped.

Document the overflow internally but assume regulatory notification is unnecessary if no receiving water impact is immediately visible.

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Question 12 of 78

A concrete sewer structure repeatedly shows severe corrosion near areas where hydrogen sulfide is present. What should a maintenance investigation consider?

Apply a protective coating immediately without evaluating the existing structural damage or the conditions producing hydrogen sulfide.

Replace only the visibly damaged concrete while leaving the recurring sulfide source and operating conditions uninvestigated.

The sulfide source, operating conditions, structural damage, and appropriate corrosion-control or rehabilitation measures.

Increase ventilation and assume no structural evaluation is necessary because reducing gas concentration will reverse existing corrosion.

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Question 13 of 78

Why are fats, oils, and grease a concern in sanitary sewer systems?

They always increase sewer capacity.

They convert gravity sewers into force mains.

They can accumulate in sewers and contribute to restrictions, blockages, and overflows.

They eliminate the possibility of root intrusion.

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Question 14 of 78

Atmospheric testing indicates a potentially flammable atmosphere in a collection-system work area. What is the BEST response?

Follow the hazardous-atmosphere procedure, control ignition sources, and do not proceed until safe entry or work conditions are established.

Use respiratory protection and continue the work without addressing the ignition and explosion hazard.

Ventilate the area briefly and begin work without repeating atmospheric testing if the odor appears to decrease.

Continue work if the combustible-gas reading is stable rather than increasing, even though it remains outside the permitted work condition.

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Question 15 of 78

Before performing a CCTV sewer inspection, why may cleaning the sewer first improve the inspection?

Removing deposits can improve camera travel and allow defects in the pipe to be seen more clearly.

CCTV equipment cannot operate in a clean sewer.

Cleaning guarantees that the sewer will never require repair.

Cleaning is used to increase the camera lens diameter.

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Question 16 of 78

Workers must perform maintenance beside an open wet well where a fall could result in serious injury. What is the BEST safety approach?

Use fall protection only after a worker has slipped near the opening.

Remove existing barriers if they make access to the equipment less convenient.

Establish the required fall-protection controls before beginning work near the exposed opening.

Rely on workers to remain several inches away from the edge instead of using the required protective controls.

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Question 17 of 78

CCTV inspection shows one severe localized pipe defect while the remainder of a sewer segment is in good condition. What should be considered when selecting a repair?

Use trenchless lining because avoiding excavation should take priority over determining whether the defect and pipe condition are suitable for lining.

Use the lowest-cost localized repair without considering the hydraulic condition, accessibility, or expected service life.

Replace the full sewer segment because one severe defect means the remaining pipe should be treated as structurally failed.

The defect extent, condition of the remaining pipe, location, hydraulics, access, and long-term repair needs.

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Question 18 of 78

What is the primary purpose of preventive maintenance in a wastewater collection system?

To reduce unexpected failures by inspecting and servicing assets before serious problems develop.

To eliminate the need for maintenance records.

To ensure equipment is serviced only after complete failure.

To increase the number of emergency repairs.

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Question 19 of 78

An operator must handle a chemical used for collection-system odor control. Which document should be reviewed for information about the chemical hazards, required PPE, first-aid measures, and spill response?

The Safety Data Sheet for the chemical.

The pump manufacturer performance curve.

The collection-system flow map.

The most recent sewer CCTV inspection report.

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Question 20 of 78

A section of sewer must be taken out of service for repair while wastewater continues to enter the upstream system. What equipment may be needed to maintain service?

A CCTV camera used as the only means of conveying wastewater.

A gas detector used as a wastewater pump.

A properly sized and monitored temporary bypass pumping system.

A drinking water chlorinator connected directly to the broken sewer.

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Question 21 of 78

What is an important function of manholes in a wastewater collection system?

They provide access for inspection, cleaning, and maintenance of the sewer system.

They provide potable drinking water storage.

They replace all wastewater pumping stations.

They eliminate the need for sewer pipes between customers and the treatment plant.

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Question 22 of 78

A new commercial customer asks what local requirements apply before connecting to the wastewater collection system. What should the operator or utility representative consult?

The requirements used by a neighboring utility, because collection-system connection rules are identical everywhere.

The oldest available connection standard, because previously adopted requirements remain applicable indefinitely.

The current applicable local sewer-use ordinance, utility requirements, codes, and other applicable regulations.

Only the pipe manufacturer installation manual, regardless of local connection and discharge requirements.

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Question 23 of 78

Why is hydrogen sulfide generation a concern in wastewater collection systems?

It increases dissolved oxygen in stagnant wastewater.

It always improves concrete strength.

It can create toxic atmospheres, odors, and conditions that contribute to sewer corrosion.

It is harmless whenever an odor can be detected.

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Question 24 of 78

A long force main operates at very low flow for extended periods. At the discharge point, operators notice increasingly septic odors. What is a likely contributing factor?

Long detention time may be allowing anaerobic conditions and hydrogen sulfide formation to develop.

The force main is removing too much grit from the wastewater.

Long detention always increases dissolved oxygen and prevents odor formation.

Low flow automatically disinfects the wastewater.

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Question 25 of 78

A utility has more identified maintenance needs than can be completed immediately. What is the BEST basis for prioritizing the work?

Complete the oldest outstanding work orders first regardless of the condition or criticality of the affected assets.

Prioritize work primarily by which tasks can be completed fastest so the greatest number of work orders can be closed.

Divide maintenance resources equally among all service areas regardless of their failure history or overflow risk.

Prioritize using risk, asset condition, failure consequences, overflow potential, and system reliability.

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Question 26 of 78

A short section of damaged sewer is being replaced and the new pipe must connect to an existing pipe of a different material. What is MOST important when making the connection?

Use an approved compatible coupling or joining method that provides proper alignment, support, and a suitable seal between the pipes.

Leave a small open gap between the pipe ends so future settlement will not place stress on the connection.

Force the smaller or more flexible pipe directly into the other pipe and seal the remaining space with any available material.

Choose the connection method only by which one can be installed fastest, regardless of the pipe materials and dimensions.

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Question 27 of 78

What is a major purpose of closed-circuit television inspection of a sewer?

To eliminate all need for sewer cleaning.

To increase the diameter of the sewer.

To observe and document the internal condition of the sewer and identify defects.

To measure chlorine residual in drinking water.

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Question 28 of 78

Why are two pumps at a duplex lift station often controlled so that the lead pump alternates between pumping cycles?

To eliminate the need for pump maintenance because alternating pumps prevents mechanical wear.

To make both pumps operate simultaneously during every normal pumping cycle regardless of incoming flow.

To prevent either pump from being tested independently.

To distribute operating time and wear between the pumps while maintaining usable backup capacity.

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Question 29 of 78

Why should a positive displacement pump generally not be operated against a closed discharge without appropriate pressure relief?

A closed discharge has no effect on this type of pump.

Pressure can rise rapidly and damage equipment or piping.

A closed discharge always reduces pressure to zero.

The pump will automatically convert wastewater into drinking water.

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Question 30 of 78

Flow records show that peak wet-weather flow in one sewer basin has increased over several years while the served population has changed very little. How can this information be useful?

The entire basin should be scheduled for replacement because an increasing wet-weather trend by itself identifies every defective sewer segment.

The trend most likely reflects population growth even though the served population has changed very little.

Historical wet-weather data should be excluded from system evaluation because only current peak flow is relevant to collection-system performance.

The trend can help identify a need to investigate increasing infiltration, inflow, or other sources of excess wet-weather flow.

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Question 31 of 78

What is a potential advantage of trenchless sewer rehabilitation compared with conventional open excavation?

It may restore the sewer while reducing surface excavation and disruption.

It automatically increases wastewater treatment capacity.

It is appropriate for every defect regardless of pipe condition.

It eliminates the need to inspect the sewer before rehabilitation.

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Question 32 of 78

Which situation is an example of inflow entering a sanitary collection system?

Return activated sludge entering an aeration basin.

Groundwater slowly entering through a cracked pipe below the water table.

Normal wastewater discharged from a commercial restroom.

Stormwater entering through an improperly connected roof drain.

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Question 33 of 78

What problem is more likely in a sewer where wastewater velocity remains unusually low for long periods?

Permanent elimination of hydrogen sulfide.

A guaranteed increase in pumping efficiency.

Automatic enlargement of the sewer pipe.

Solids deposition and an increased risk of blockage.

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Question 34 of 78

Why should a collection-system utility maintain an appropriate inventory of critical replacement parts?

It eliminates the need for trained maintenance personnel.

It guarantees that equipment will never fail.

It can reduce service-restoration delays when critical equipment fails.

It prevents infiltration from entering gravity sewers.

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Question 35 of 78

Why is proper traffic control important when collection-system work is performed in a roadway?

To increase wastewater velocity in the sewer.

To determine pump discharge pressure.

To eliminate the need for personal protective equipment.

To protect workers and the public and guide traffic safely around the work zone.

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Question 36 of 78

What is the purpose of having an appropriately certified available operator for a Pennsylvania wastewater system?

To eliminate the need for operating procedures.

To require the same certified operator to stand beside every sewer manhole at all times.

To allow any non-certified employee to make unrestricted process control decisions.

To ensure that an appropriately certified operator can make or direct process control decisions when needed.

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Question 37 of 78

Which situation is an example of infiltration into a sanitary sewer?

Roof drains connected directly to a sanitary sewer.

Wastewater discharged from a residential toilet.

Groundwater entering through cracked sewer pipe or leaking joints.

Wastewater pumped through a force main.

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Question 38 of 78

During a severe storm, flow to a lift station rises rapidly. One duty pump has failed, the wet-well level is approaching the high-high alarm, and an overflow could occur if the level continues to rise. What is the BEST overall response?

Reduce the high-level alarm setting and continue monitoring the station without arranging additional pumping capacity or evaluating backup options.

Concentrate on repairing the failed duty pump before activating bypass or other emergency measures, even while the wet-well level continues to rise.

Place the remaining pump in continuous operation and postpone emergency-response and overflow preparations until wastewater actually reaches the overflow point.

Implement the emergency response, maximize safe available pumping or bypass capacity, monitor the wet well, and address notification and overflow risks.

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Question 39 of 78

A non-certified employee is carrying out an action clearly defined in an approved SOP. A new condition develops that requires a process control decision not covered by the SOP. What should the employee do?

Contact the appropriately certified operator for direction before making the process control decision outside the SOP.

Ask a non-certified supervisor to authorize the process control decision when the certified operator is not immediately present.

Use the step in the approved SOP that is most similar to the new condition and notify the certified operator afterward.

Make a temporary process control decision to stabilize the system and obtain certified-operator approval after the change is made.

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Question 40 of 78

Why might an inverted siphon be used in a gravity sewer system?

To store drinking water above ground.

To prevent any wastewater from flowing through a sewer.

To remove all dissolved pollutants without treatment.

To convey wastewater beneath an obstacle where a normal gravity-sewer profile is not practical.

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Question 41 of 78

What is the purpose of a check valve on a wastewater pump discharge line?

To prevent reverse flow through the discharge line.

To provide ventilation for confined spaces.

To remove grit from the wet well.

To measure dissolved oxygen in wastewater.

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Question 42 of 78

An operator discovers wastewater overflowing from a sanitary sewer manhole. What is the BEST general response?

Contain the wastewater and document the event internally, but assume outside notification is unnecessary if the overflow is stopped quickly.

Concentrate first on restoring sewer flow and postpone public-protection and notification actions until the final overflow volume is known.

Follow the emergency procedure, protect people and the environment, address the cause, and make required notifications and records.

Enter the affected manhole immediately to remove the blockage before completing the applicable atmospheric and entry-safety procedures.

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Question 43 of 78

A lift-station pump has undergone major maintenance and is ready to be returned to service. What is the BEST approach before restoring normal automatic operation?

Return the pump directly to AUTO because successful completion of the repair makes an operational test unnecessary.

Leave guards removed during the initial operating period so the repaired components can be observed more closely.

Operate the pump at maximum output immediately so any remaining mechanical problems become obvious as quickly as possible.

Complete the required pre-start checks, safely restore the equipment, test its operation, and monitor it before returning it to normal automatic service.

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Question 44 of 78

What is the primary purpose of a sanitary wastewater collection system?

To collect only stormwater from streets and parking lots.

To provide drinking water to customers.

To convey sanitary wastewater to a location where it can be properly treated or managed.

To eliminate the need for wastewater treatment.

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Question 45 of 78

What is the purpose of a mechanical root-cutting tool used in a sewer?

To increase wastewater pH.

To remove intrusive roots that restrict wastewater flow.

To measure hydrogen sulfide concentration.

To permanently seal every defective joint while cutting roots.

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Question 46 of 78

Why can excessive infiltration and inflow create serious collection-system problems during wet weather?

It eliminates the need for pumping stations.

It permanently increases the diameter of sewer pipes.

It always reduces wastewater flow during storms.

It can consume collection-system capacity and contribute to surcharging, overflows, and excessive downstream flow.

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Question 47 of 78

A lift-station pump does not start automatically when the wet-well level passes its normal start point. In manual mode, the pump starts and produces normal flow. What should the operator investigate?

A blocked pump impeller, even though the pump produces normal flow when operated manually.

The level-sensing and automatic control system, including its setpoints, interlocks, and related control components.

A closed discharge valve, even though normal manual pumping confirms that the hydraulic path is open.

A failed motor power supply, even though the motor starts and operates normally in manual mode.

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Question 48 of 78

What can smoke testing help identify in a sanitary sewer system?

The exact BOD concentration of wastewater.

Potential inflow connections and openings connected to the sanitary sewer.

The chlorine demand of final effluent.

The dry solids concentration of sludge.

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Question 49 of 78

A sewer profile shows an upstream invert elevation of 103.0 feet and a downstream invert elevation of 101.0 feet over a horizontal distance of 400 feet. What is the approximate sewer slope?

0.05 percent

0.50 percent

2.0 percent

5.0 percent

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Question 50 of 78

Inspection finds groundwater entering continuously through several defective sewer joints during dry weather. What is the BEST interpretation?

The joints should be opened further to relieve groundwater pressure.

The water is inflow because all groundwater is classified as inflow.

The defects are a source of infiltration and should be evaluated for repair or rehabilitation.

The condition cannot affect downstream hydraulic loading.

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Question 51 of 78

Why is the sense of smell NOT a reliable method for determining whether hydrogen sulfide is at a safe concentration?

Hydrogen sulfide can impair the sense of smell, so a dangerous atmosphere may remain even when odor is no longer noticed.

If the odor disappears, the gas has always left the area.

Hydrogen sulfide has no odor at any concentration.

Hydrogen sulfide is hazardous only when it becomes visible.

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Question 52 of 78

A wastewater flow meter indicates a constant flow of 200 gallons per minute. Approximately how many gallons will pass in 24 hours?

288,000 gallons

12,000 gallons

120,000 gallons

2,880,000 gallons

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Question 53 of 78

Why are accurate collection-system maps important?

They help operators locate and understand collection-system assets during operation, maintenance, and emergencies.

They are used only for customer billing.

They eliminate the need for field inspections.

They guarantee that sewer blockages cannot occur.

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Question 54 of 78

Which factors should be considered when selecting pipe material for a wastewater collection-system installation or replacement?

Only the initial purchase price, because installation and environmental conditions do not affect pipe performance.

Site conditions, loading, corrosion potential, installation and joining requirements, and applicable specifications.

Always use the same material as the nearest existing pipe regardless of its condition or the new installation requirements.

Select material only by internal diameter because pipe material does not affect construction or long-term performance.

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Question 55 of 78

What is the primary purpose of an odor-control unit such as a biofilter or gas scrubber connected to the ventilation system of a wastewater lift station?

To measure the wastewater level used by the automatic pump controls.

To replace the lift-station wastewater pumps during high-flow conditions.

To increase wastewater flow through the force main by creating additional pipe pressure.

To remove or reduce odor-causing compounds in ventilation air before it is discharged.

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Question 56 of 78

A worker collapses inside a sewer manhole and the cause is unknown. What should an unprotected coworker do?

Initiate the established rescue procedure and do not enter the space without the required protection and rescue capability.

Enter using a retrieval rope but without confirming atmospheric conditions or implementing the required confined-space rescue procedure.

Have the attendant enter wearing an ordinary cartridge respirator while another employee remains outside the manhole.

Ventilate the manhole briefly and enter immediately if the collapsed worker can be seen from the opening.

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Question 57 of 78

Why should an emergency generator serving a critical lift station be exercised and tested periodically?

To increase infiltration into the collection system.

To make the lift station use more electricity during normal operation.

To eliminate the need for wastewater pumps.

To verify that backup power will operate reliably when normal power is lost.

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Question 58 of 78

A maintenance report shows that 200 preventive-maintenance tasks were scheduled during the year and 170 were completed. What percentage of the scheduled tasks were completed?

80 percent

117.6 percent

70 percent

85 percent

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Question 59 of 78

A sewer segment repeatedly accumulates loose sediment and grease but has no known structural failure. What is an appropriate maintenance approach?

Use an appropriate sewer-cleaning method based on the type and amount of material present.

Ignore the deposits until a complete blockage occurs.

Add drinking water disinfectant and assume the deposits will disappear.

Replace the entire sewer automatically whenever loose deposits are found.

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Question 60 of 78

What does it mean when a gravity sewer is surcharged?

The sewer has been converted into a potable water main.

The pipe has automatically increased in diameter.

The wastewater level has risen enough that the sewer is operating under pressure rather than normal open-channel flow.

The sewer contains no wastewater.

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Question 61 of 78

Several residents in the same area report sewer backups within a short period. How should the reports be handled?

Assume each complaint is unrelated without checking the collection system.

Document and compare the reports with system information and investigate the affected area.

Delete the complaints after advising customers to wait.

Ignore the complaints unless every customer in the system reports a backup.

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Question 62 of 78

Water is standing on the floor near a damaged electrical control enclosure at a lift station. What is the BEST response?

Stand on a dry temporary surface and open the damaged energized enclosure to determine where the water entered.

Avoid contact, secure the hazard, and have qualified personnel address the electrical condition using appropriate safety procedures.

Turn the local selector switch to OFF and begin electrical work without completing the required energy-isolation procedure.

Wear rubber gloves and reset the affected electrical equipment while leaving the damaged enclosure energized.

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Question 63 of 78

What BEST describes a combined sewer overflow, or CSO?

Any sanitary sewer overflow from a separate sanitary sewer, regardless of whether stormwater is conveyed in the pipe.

A wet-weather discharge from a combined system that carries both sanitary wastewater and stormwater when combined flow exceeds available downstream capacity.

Normal discharge from a wastewater pump into a force main.

Groundwater entering a cracked sanitary sewer below the groundwater table.

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Question 64 of 78

Why is adequate slope important in a gravity sewer?

Slope is used only to determine manhole cover size.

Slope is needed only to increase wastewater temperature.

A gravity sewer operates independently of elevation.

Adequate slope helps produce flow velocity that transports wastewater and suspended material.

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Question 65 of 78

Maintenance must be performed on a wastewater pump that could start automatically. What should be done before work begins?

Work quickly before the pump has time to restart.

Ask another worker to watch the pump controls while maintenance is performed.

Follow the applicable lockout/tagout procedure and verify that hazardous energy has been controlled.

Place the automatic control switch in OFF and assume no further isolation is needed.

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Question 66 of 78

Wastewater levels in several upstream manholes rise substantially while a downstream manhole remains unusually low. What should the operator suspect?

The downstream pipe must be completely full because its manhole level is low.

The condition proves that infiltration cannot be present anywhere in the system.

A restriction or blockage may exist between the high upstream levels and the lower downstream location.

The upstream sewer pipes must have increased in diameter.

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Question 67 of 78

Why is proper nozzle selection important when using high-pressure water to clean a sewer?

The largest nozzle should always be used regardless of pipe size.

Different nozzles are suited to different pipe conditions and types of deposits.

Nozzle selection affects only the color of the cleaning water.

Every sewer-cleaning nozzle produces exactly the same hydraulic action.

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Question 68 of 78

A pump bearing begins running hotter shortly after it is greased. What should the maintenance investigation consider?

Continue operating until the bearing temperature stabilizes without checking the recent lubrication work.

Add additional grease immediately because a hot bearing always indicates insufficient lubrication.

Replace the specified lubricant with a different product without checking equipment requirements.

Verify the lubricant type and quantity and investigate possible overgreasing, contamination, bearing condition, and related mechanical problems.

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Question 69 of 78

Why can industrial pretreatment be important to a municipal wastewater collection and treatment system?

It can control harmful industrial discharges before they damage the collection system or interfere with wastewater treatment.

It eliminates the need for a wastewater treatment plant.

It allows every industrial user to discharge any material without restriction.

Its only purpose is to increase sanitary sewer flow.

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Question 70 of 78

A lift-station level transmitter indicates 8.0 feet of wastewater while an independent physical measurement shows approximately 6.0 feet. What is the BEST maintenance response?

Accept the transmitter reading because an electronic instrument should take priority over a physical measurement.

Verify the reference measurement and inspect and calibrate the level-measurement system according to the applicable procedure.

Change the displayed level to six feet without investigating the transmitter, sensor, or scaling.

Change all pump start and stop setpoints by two feet so they match the indicated transmitter level.

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Question 71 of 78

During routine manhole inspection, which condition should receive maintenance attention?

An accurate identification number on the system map.

Cracks, corrosion, infiltration, or damaged channels and structural components.

A properly seated cover with no visible defects.

A clean access area with no evidence of damage.

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Question 72 of 78

What must a Pennsylvania certified wastewater operator do to maintain certification through the normal renewal process?

Remain employed by the same system and take no further action.

Complete the applicable continuing education requirements and submit a timely renewal application.

Wait until DEP issues a violation before renewing the certificate.

Retake every certification examination every year.

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Question 73 of 78

Why should isolation valves associated with a force main be inspected and exercised according to the system maintenance program?

To increase hydrogen sulfide production.

To improve the likelihood that the valves will operate when isolation is required.

To permanently increase the diameter of the force main.

To eliminate the need for pump maintenance.

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Question 74 of 78

What is an important advantage of using a computerized maintenance or work-order system for a wastewater collection system?

It automatically performs collection-system maintenance once a work order has been entered.

It can organize asset history, schedule and track work, and help identify recurring failures and maintenance trends.

Its primary purpose is to replace maps, operating procedures, and equipment manuals with a single work-order number.

It removes the need to verify field conditions because computer records should always be considered more accurate than observations.

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Question 75 of 78

What is a force main in a wastewater collection system?

A gravity sewer that can never contain pressure.

An open channel used only for stormwater.

A pipe used exclusively for potable water.

A pressurized pipeline used to convey wastewater discharged by a pump.

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Question 76 of 78

A centrifugal wastewater pump develops a gravel-like rattling sound, increased vibration, reduced flow, and unusually poor suction conditions. What condition should the operator consider?

A normal increase in pumping efficiency caused by lower suction pressure.

A partially restricted discharge alone, even though the strongest abnormal indications are occurring on the suction side.

An automatic level-control problem only, even if the pump continues to run and the abnormal hydraulic and mechanical symptoms remain.

Cavitation or another condition causing inadequate suction at the pump.

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Question 77 of 78

A sewer basin has unusually high flow during overnight hours when sanitary wastewater generation is normally low. The condition continues during several dry-weather days. What should the operator consider investigating?

Only stormwater inflow, because dry-weather flow can never indicate infiltration.

Possible infiltration or another abnormal continuous source of flow.

Nothing, because collection-system flow patterns provide no useful operational information.

A complete blockage, because a blocked sewer always produces higher measured downstream flow.

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Question 78 of 78

Wastewater is flowing through a channel with a cross-sectional flow area of 2 square feet at an average velocity of 3 feet per second. What is the approximate flow rate?

6 cubic feet per second

12 cubic feet per second

5 cubic feet per second

1.5 cubic feet per second

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