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CWEA COLLECTION SYSTEMS MAINTENANCE EXAM
2025 - 2026 / 150 VERIFIED Qs&As|ALREADY GRADED
A+
Why are gasoline and volatile solvents objectionable when present in a sewer? - ANS:->>>They produce an explosion hazard You should never attempt to install, maintain, repair or replace electrical equipment panels, controls, wiring or circuits unless - ANS:->>>You know what you are doing, are qualified and are authorized What are the different areas of traffic zones? - ANS:->>> Advance Warning Area, Transition Area, Activity Area (buffer space and work space), Termination Area. Could be 4 or 5, justify your answer on the test! why should hydrogen sulfide be controlled? - ANS:->>>to protect from corrosion and odors Personnel entering a Permit Required Confined Space must have the following training - ANS:->>>entry and rescue To find protective gear before application of a product, you should: - ANS:-
>>>look at the MSDS The gas most commonly associated with septic wastewater is - **ANS:-
** Hydrogen Sulfide The lack of an unpleasant odor in a manhole, lift station or other structures does not always mean that dangerous gases are not present because: - ANS:->>> some dangerous gasses are odorless (for example, carbon monoxide) What are the four conditions necessary to create an explosion? - ANS:- combustible gas, adequate oxygen, heat and proper mixing of gas and oxygen what does the "transition area" mean in traffic control? - ANS:->>>It moves traffic out of its normal path what elements should be considered to improve worker safety in High speed Temporary Traffic control Zones? - ANS:->>>Rerouting traffic around the work site, positioning of law enforcement officers in the temporary traffic control zone, and work zone training
The L.O.T.O Program What does L.O.T.O. Stand for? - ANS:->>>Lock out tag out What document would you require to be referenced when developing an S.O.p. for hazardous substace spill clean up? - ANS:->>>M.S.D.S. in developing an S.O.P. for air monitoring in a Permit Required Confined Space you would include what two factors? - ANS:->>>Placement of the blower and a entry and rescue** To find protective gear before application of a product, you should: - ANS:- >>>look at the MSDS The gas most commonly associated with septic wastewater is - ANS:- >>> Hydrogen Sulfide The lack of an unpleasant odor in a manhole, lift station or other structures does not always mean that dangerous gases are not present because: - ANS:->>> some dangerous gasses are odorless (for example, carbon monoxide) What are the four conditions necessary to create an explosion? - ANS:- >>>combustible gas, adequate oxygen, heat and proper mixing of gas and oxygen what does the "transition area" mean in traffic control? - ANS:->>>It moves traffic out of its normal path what elements should be considered to improve worker safety in High speed Temporary Traffic control Zones? - ANS:->>>Rerouting traffic around the work site, positioning of law enforcement officers in the temporary traffic control zone, and work zone training >>>The L.O.T.O Program What does L.O.T.O. Stand for? - ANS:->>>Lock out tag out What document would you require to be referenced when developing an S.O.p. for hazardous substace spill clean up? - ANS:->>>M.S.D.S. in developing an S.O.P. for air monitoring in a Permit Required Confined Space you would include what two factors? - ANS:->>>Placement of the blower and a weather forecast According to the State Water Resources Control Board Order No. 2006 - 003 - DWQ, each enrollee must develop and implement a system-specific: - ANS:- SSMP (Sewer System Management Plan) How long do you have to report a category 1 SSO? - ANS:->>> 2 hours To report in the Statewide SSO Data-base California Integrated Water Quality System (CIWQS) regarding the location of a Category 2 SSO, how must you report the location? - ANS:->>>Using the GPS coordinates
Biological activity in long, sluggish-flow, flat grade sewer lines will likely cause: - ANS:->>>odors Flatter sewer line grades may cause added sewer maintenance expense and odor nuisance. This is caused by what? - ANS:->>>A decrease in velocity which allows organic and inorganic solids to settle out. This, in turn, allows biological activity to happen which corrodes the pipe and releases hydrogen sulfide (H2S) which smells like rotten eggs Clear water in entering a collection system is called what? - ANS:->>>infiltration Infiltration can occur in a pipe when the pipe is: - ANS:->>>cracked, broken, fractures, has roots coming into it etc. The main reason we add sodium hypochlorite to sewers is to control: - ANS:-
BOD Roots can enter collection systems through: - ANS:->>>cracked pipes, broken pipes, fractured pipes The lowest point on the inside of a pipe is called what? - ANS:->>>the invert
What are some sewer testing methods? - ANS:->>>Air, water, mandrill, smoke, dye, lamping What are some hydraulic cleaning methods? - ANS:->>>Flushing, balling, kites, parachutes, poly pigs (pigging), high velocity cleaning, jetting, skids and tiger tails. what is the formula for the area of a square? - ANS:->>>Length x width The main advantage of using CCTV is what? - ANS:->>>You can see and record the length and severity of defective pipe A hazard that may damage a TV camera going through a sewer is: - ANS:->>>an offset joint What is the formula for the volume of a cube? - ANS:->>>Length x Width x Height What is the formula for the area of a circle? - ANS:->>>0.785 x Diameter x Diameter
What is the formula for the volume of a pipe? - ANS:->>>0.785 x Diameter x Diameter x Length A flow of 650 pgm would be how many mgd? - ANS:->>>0. How can the members of a balling crew communicate with each other? - ANS:-
Hand Signals Why must you always know where a cleaning tool is in a sewer? - ANS:->>>so
cracked, broken, fractures, has roots coming into it etc. The main reason we add sodium hypochlorite to sewers is to control: - ANS:- >>>BOD Roots can enter collection systems through: - ANS:->>>cracked pipes, broken pipes, fractured pipes The lowest point on the inside of a pipe is called what? - ANS:->>>the invert What are some sewer testing methods? - ANS:->>>Air, water, mandrill, smoke, dye, lamping What are some hydraulic cleaning methods? - ANS:->>>Flushing, balling, kites, parachutes, poly pigs (pigging), high velocity cleaning, jetting, skids and tiger tails. what is the formula for the area of a square? - ANS:->>>Length x width The main advantage of using CCTV is what? - ANS:->>>You can see and record the length and severity of defective pipe A hazard that may damage a TV camera going through a sewer is: - ANS:->>>an offset joint What is the formula for the volume of a cube? - ANS:->>>Length x Width x Height What is the formula for the area of a circle? - ANS:->>>0.785 x Diameter x Diameter What is the formula for the volume of a pipe? - ANS:->>>0.785 x Diameter x Diameter x Length A flow of 650 pgm would be how many mgd? - ANS:->>>0. How can the members of a balling crew communicate with each other? - ANS:- >>>Hand Signals Why must you always know where a cleaning tool is in a sewer? - ANS:->>>so you know where obstructions or difficulties are encountered emergency stoppages in pipelines may be cleared safely by use of: - ANS:-
high velocity cleaners rodents and insects can be controlled by - ANS:->>>spraying manholes with an approved pesticide Sources of excessive clear water in a collection system are usually caused by: - ANS:->>>infiltration from a high water table How many types of common shoring are there? - ANS:->>> 6
What control devices are used to start and stop pumps? - ANS:->>>Floats What type of pump is used in lift station wet wells? - ANS:->>>Submersible Based on new Best Practices of the Common Ground Alliance for marking underground Utilities, the Inquiry Identification Number for an Underground Service Alert (USA) is viable for how many days? - ANS:->>> 28 days A person who completes a training program in accordance with the requirements of Title 8, Calif. Code of Regulations, Minimum Guidelines of the Common Ground Alliance is considered a person - ANS:->>>Qualified Person You receive a dispatch at 4:30 pm informing you that raw sewage spewing out of a manhole onto the ground and into an adjacent small stream. The caller said the sewer has been overflowing since 2pm. You arrive at 5:15 and find that the spill is overflowing at 166 gallons per minute. You clear the problem after 22 minutes, how many reportable unrecoverable gallons of raw sewage had reached the creek? - ANS:->>>36,022 gallons (don't be intimidated by how long these word problems are! Just find the important information and take it one step at a time.) "High priority subsurface installations ae high pressure natural gas pipelines
with normal operating pressures greater than 415 kPa gauge, petroleum pipelines, conductors or cables that are potentially hazardous to employees, or the public, if damaged." This paragraph indicates that before the start date of an excavation, what should occur? - ANS:->>>An agreed upon site visit Temporary traffic control lanes created as part of a Temporary Traffic control Zone setup on a street with a 35 MPH maximum speed limit shall be a minimum width of - ANS:->>> 10 ft For a nighttime Short Term Stationary Traffic Control Zone setup on low speed/ low volume street, the minimum height of the traffic cones used shall be
- ANS:->>> 28 inches After completing a Temporary Traffic Control setup for your work zone it is a good practice to: - ANS:->>>Observe how effective your TTC setup is working to control traffic and make the necessary changes When a citizen wants information regarding a maintenance operation you should: -
What is the minimum velocity in a gravity sewer pipe? - ANS:->>> 2 ft/s. This speed prevents the settling of solids, which in turn prevents corrosion and odor build-up What are the access points of a gravity sewer system? - ANS:->>>Manholes, Lift stations, Building connections, junction chambers, terminal cleanouts What is an Easement? - ANS:->>>The legal right that allows placement of sewer in privately owned property What is the springline? - ANS:->>>The theoretical center of the pipe What is the top of the pipe called? - ANS:->>>The crown What is the lowest point inside of a pipe called? - ANS:->>>The invert
What are some examples of rigid pipe? - ANS:->>>Vitrified clay pipe (VCP), Concrete pipe, other rigid pipe, cast iron. They can support loads without as much back fill/ side support, but cannot distort without cracking or breaking What are some examples of flexible pipe? - ANS:->>>Ductile-iron pipe, steel pipe, thermoplastic pipe (PVC, HDPE, ABS), Orangeburg What is the name of the testing that confirms your pipe was not bent under pressure from being buried?
- ANS:->>>Mandrel Inspection, also know as "pigging" What is an Operating Range? - ANS:->>>It is the range in which the pump in a pump station is on What are some examples of level control devices (devices that turn a pump at a pump station on and off)? - ANS:->>>Bubbler Level Gauge, Mercury/Mechanical Float Switches, Ultra Sonic Sensor
550 gallons of sewage overflow and do not reach any surface waters. What category of overflow is this? - ANS:->>>Category 3 What does FOG stand for? - ANS:->>>Fats, oils and greases What are some examples of additives that can prevent FOG build up? - ANS:-
Chemical degreasers, emulsifying degreasers, enzymes and bacteria What are the pros and cons of balling/kites and parachutes? - ANS:- Pros:dislodges debris, settled inorganics, and small roots from the sewer line, prevents build-up of grease, mitigates H2S odor by removing slime and can be used in large diameter sewers, kites can collapse to prevent flooding Cons: risk of flooding buildings, doesn't work well on steep grades, makes stoppages worse if stoppage is below the sewer ball.
what should you do before cleaning sewers? - ANS:->>>Notify downstream treatment plants and pump stations. What are poly pigs used for? - ANS:->>>to clean sewer force mains. They are propelled by pressurized water flow What are some cons to hydro jetting? - ANS:->>>Efficiency decreases as pipe size decreases, may require multiple passes to fully remove grease and roots What does SDS stand for? - ANS:->>>Safety Data Sheet What does GISO stand for? - ANS:->>>General Industry Safety Orders. This is in the Cal/OSHA construction safety orders bookWhat does CSO stand for? and establishes minimum occupational safety and health standards What does MUTCD Stand for? - ANS:->>>Manual on Uniform Traffic Control Devices
What is a qualified person? - ANS:->>>designated by the employer by reason of training, experience, instruction, previous demonstration of the ability to safely perform all assigned duties, properly licensed with federal, state and local laws and regulations What does SWP stand for? - ANS:->>>Safe Work Procedures What does PPE stand for? - ANS:->>>Personal Protective Equipment What does PPE do? - ANS:->>>Personal Protective Equipment is used to create a protective barrier between a worker and hazards in the workplace. It is critical in everyday operation and protects from burns, chemical and biological exposure, bruises, fractures, abrasions, cuts, punctures, and amputations. What is required when there is a potential injury to the head from falling objects? - ANS:->>>Head Protection
When is hearing protection required? - ANS:->>>When noise could induce hearing loss When is foot protection required? - ANS:->>>When there is potential for serious injury to the foot from daily job duties When is hand protection required? - ANS:->>>When there is the potential for injury or exposure to skin contact from chemicals, infectious agents, heat, cold, abrasive or cutting objects What are the four classes of chemical hazards? - ANS:->>>Flammability, Toxicity, Corrosivity, Reactivity What is the scale for the level of hazard for chemicals - ANS:->>> 0 - 4, 0 being minimal and 4 being extreme What precautions should be taken for a chemical with a high flammability
