CWEA Collection Systems Maintenance Grade 1 and 2 Test Exam with Questions and Well Verified Answers [Graded A+] 2026/2027

CWEA CWEA CWEA Collection Systems Maintenance Grade 1 and 2 Test Exam with Questions and Well Verified Answers [Graded A+] 2026/2027 Why are gasoline and volatile solvents objectionable when present in a sewer? - Correct Ans-They produce an explosion hazard You should never attempt to install, maintain, repair or replace electrical equipment panels, controls, wiring or circuits unless - Correct Ans-You know what you are doing, are qualified and are authorized What are the different areas of traffic zones? - Correct 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? - Correct Ans-to protect from corrosion and odors Personnel entering a Permit Required Confined Space must have the following training - Correct Ans-entry and rescue To find protective gear before application of a product, you should: - Correct Ans-look at the MSDS The gas most commonly associated with septic wastewater is - Correct 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: - Correct Ans-some dangerous gasses are odorless (for example, carbon monoxide) What are the four conditions necessary to create an explosion? - Correct Ans combustible gas, adequate oxygen, heat and proper mixing of gas and oxygen what does the "transition area" mean in traffic control? - Correct Ans-It moves traffic out of its normal path CWEA CWEA what elements should be considered to improve worker safety in High speed Temporary Traffic control Zones? - Correct Ans-Rerouting traffic around the work site, positioning of law enforcement officers in the temporary traffic control zone, and work zone training What key features would you need to address when developing an S.O.P. for a Lift Station failure? - Correct Ans-Traffic Control Plan, By-Pass connections, and Spill containment What tools are used with a power rodder? - Correct Ans-Spring Blades Tools used for sewer rodding include: - Correct Ans-porcupine, root saw, square bar cork screw What tool would you use to cut VCP pipe? - Correct Ans-Chain Pipe Cutter Which conditions should a gas detection device test for? - Correct Ans-Hydrogen sulfide, explosive/flammable gases, oxygen What does "LEL" mean on a gas detection meter? - Correct Ans-Lower Explosive Limit The oxygen level alarm normally goes off if oxygen levels are below: - Correct Ans-19.5 percent When developing an S.O.P. for scheduled maintenance of electrical equipment, what program should be addressed as a primary safety guideline? - Correct Ans-The L.O.T.O Program What does L.O.T.O. Stand for? - Correct 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? - Correct 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? - Correct 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: - Correct Ans-SSMP (Sewer System Management Plan) How long do you have to report a category 1 SSO? - Correct 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? - Correct Ans-Using the GPS coordinates CWEA CWEA Biological activity in long, sluggish-flow, flat grade sewer lines will likely cause: - Correct Ans-odors Flatter sewer line grades may cause added sewer maintenance expense and odor nuisance. This is caused by what? - Correct 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? - Correct Ans-infiltration Infiltration can occur in a pipe when the pipe is: - Correct Ans-cracked, broken, fractures, has roots coming into it etc. The main reason we add sodium hypochlorite to sewers is to control: - Correct Ans BOD Roots can enter collection systems through: - Correct Ans-cracked pipes, broken pipes, fractured pipes The lowest point on the inside of a pipe is called what? - Correct Ans-the invert The very top of the outside of a pipe is called what? - Correct Ans-The crown How often must an excavation site and adjacent areas be inspected for hazardous conditions? - Correct Ans-Daily protective shoring systems options include: - Correct Ans-proper shoring or benching of the sides of the excavation, supporting the sides of a tench with shoring using a shield in an excavation area. Proper operation and maintenance of wastewater collection is defined as: - Correct Ans keeping wastewater flowing through pipes What is minimum design velocity for a sewer? - Correct Ans-a minimum of two feet per second Vitrified clay pipe is what type of pipe? - Correct Ans-Rigid What is another name for a manhole? - Correct Ans-Maintenance hole What are the four parts of a manhole? - Correct Ans-lid, cone, barrel and base What are some sewer testing methods? - Correct Ans-Air, water, mandrill, smoke, dye, lamping CWEA CWEA What are some hydraulic cleaning methods? - Correct 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? - Correct Ans-Length x width The main advantage of using CCTV is what? - Correct 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: - Correct Ans-an offset joint What is the formula for the volume of a cube? - Correct Ans-Length x Width x Height What is the formula for the area of a circle? - Correct Ans-0.785 x Diameter x Diameter What is the formula for the volume of a pipe? - Correct Ans-0.785 x Diameter x Diameter x Length A flow of 650 pgm would be how many mgd? - Correct Ans-0.936 How can the members of a balling crew communicate with each other? - Correct Ans Hand Signals Why must you always know where a cleaning tool is in a sewer? - Correct Ans-so you know where obstructions or difficulties are encountered emergency stoppages in pipelines may be cleared safely by use of: - Correct Ans-high velocity cleaners rodents and insects can be controlled by - Correct Ans-spraying manholes with an approved pesticide Sources of excessive clear water in a collection system are usually caused by: - Correct Ans-infiltration from a high water table How many types of common shoring are there? - Correct Ans-6 What is the "dirt" formula? - Correct Ans-distance = rate x time What is the total volume (in gallons) of 1,000 feet of 8-inch pipeline? - Correct Ans 2,611 gallons What is the most critical task in operation and maintenance of wastewater collection? - Correct Ans-Keeping wastewater flowing through pipes CWEA CWEA Once enrolled in CIWQS, the "Collection System Questionnaire" must be updated at least every: - Correct Ans-12 Months You arrive at an SSO and relieve the stoppage 27 minutes after a call was placed to report it. You find that the spill was running at 6 gallons per minute, how much sewage went uncaptured? - Correct Ans-162 gallons What would cause a pump to deliver less than its expected rate of discharge? - Correct Ans-clogged impeller Why are wear rings installed in a pump? - Correct Ans-To concentrate wear on rings instead of volute and impeller What control devices are used to start and stop pumps? - Correct Ans-Floats What type of pump is used in lift station wet wells? - Correct 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? - Correct 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 - Correct 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? - Correct 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? - Correct 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 ______ - Correct 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 ________ - Correct Ans-28 inches CWEA CWEA After completing a Temporary Traffic Control setup for your work zone it is a good practice to: - Correct 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: - Correct Ans-Give them as much factual information as you can and offer to help them further Before starting a maintenance operation in a basement located in the backyard of a residence you should: - Correct Ans-contact the resident and politely ask permission to enter their backyard Maintenance programs are based on: - Correct Ans-Preventative and corrective maintenance principles The goal of preventative maintenance is to? - Correct Ans-Avoid breakdowns, severe damage, or harmful depreciation What is the definition of a sanitary sewer system? - Correct Ans-Any system of pipes, pump stations, sewer lines, or other conveyances, upstream of a wastewater treatment plant head work comprised of more than one mile of pipes and sewer lines, used to collect and convey wastewater to a publicly owned treatment facility What is the definition of "hydraulic capacity"? - Correct Ans-The maximum flow a pipe is expected to function at without creating a back up or discharge What is the minimum velocity in a gravity sewer pipe? - Correct 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? - Correct Ans-Manholes, Lift stations, Building connections, junction chambers, terminal cleanouts What is an Easement? - Correct Ans-The legal right that allows placement of sewer in privately owned property What is the springline? - Correct Ans-The theoretical center of the pipe What is the top of the pipe called? - Correct Ans-The crown What is the lowest point inside of a pipe called? - Correct Ans-The invert What are some examples of rigid pipe? - Correct 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 CWEA CWEA What are some examples of flexible pipe? - Correct 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? - Correct Ans-Mandrel Inspection, also know as "pigging" What is an Operating Range? - Correct 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)? - Correct Ans-Bubbler Level Gauge, Mercury/Mechanical Float Switches, Ultra Sonic Sensor What are some common types of valves? - Correct Ans-Plug, Gate, Butterfly, Ball, Check What is infiltration? - Correct Ans-water ENTERING a sewer through pipe joints, cracks or voids what is ex-filtration? - Correct Ans-leakage OUT of pipes through joints, cracks or voids What is a confined space? - Correct Ans-A space with limited or restricted meas for entry or exit that is NOT designed for continuous employee occupancy. What is the upper oxygen concentration that would indicate a hazardous atmosphere? - Correct Ans-23.5% How long do you have to report a category 2 or 3 SSO? - Correct Ans-3 days 550 gallons of sewage overflow and do not reach any surface waters. What category of overflow is this? - Correct Ans-Category 3 What does FOG stand for? - Correct Ans-Fats, oils and greases What are some examples of additives that can prevent FOG build up? - Correct Ans Chemical degreasers, emulsifying degreasers, enzymes and bacteria What are the pros and cons of balling/kites and parachutes? - Correct 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. CWEA CWEA what should you do before cleaning sewers? - Correct Ans-Notify downstream treatment plants and pump stations. What are poly pigs used for? - Correct Ans-to clean sewer force mains. They are propelled by pressurized water flow What are some cons to hydro jetting? - Correct Ans-Efficiency decreases as pipe size decreases, may require multiple passes to fully remove grease and roots What does SDS stand for? - Correct Ans-Safety Data Sheet What does GISO stand for? - Correct 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? - Correct Ans-Manual on Uniform Traffic Control Devices What does ANSI Stand for? - Correct Ans-American National Standards Institute What does CSO stand for? - Correct Ans-Construction Safety Orders Which of the following means you HAVE to do something? you Shall, you Should, you May - Correct Ans-Shall What is the OSHA definition of a competent person? - Correct Ans-someone who is capable of identifying existing and predictable hazards in the surroundings,or working conditions which are unsanitary, hazardous, or dangerous to employees AND who has the authorization to take prompt corrective measure to eliminate them what are some characteristics of a competent person? - Correct Ans-Trained and knowledgeable, can identify soil class, understands the importance of PPE and the SDS, knows how to identify problems What is a qualified person? - Correct 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? - Correct Ans-Safe Work Procedures What does PPE stand for? - Correct Ans-Personal Protective Equipment What does PPE do? - Correct 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. CWEA CWEA What is required when there is a potential injury to the head from falling objects? - Correct Ans-Head Protection When is hearing protection required? - Correct Ans-When noise could induce hearing loss When is foot protection required? - Correct Ans-When there is potential for serious injury to the foot from daily job duties When is hand protection required? - Correct 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? - Correct Ans-Flammability, Toxicity, Corrosivity, Reactivity What is the scale for the level of hazard for chemicals - Correct Ans-0-4, 0 being minimal and 4 being extreme What precautions should be taken for a chemical with a high flammability hazard? - Correct Ans-Keep them stored in approved containers, keep emergency extinguishing agents on hand when handling and near them in storage What are some examples of toxic chemicals? - Correct Ans-disinfectants, insect repellent, antifreeze, ammonia, mothballs, motor oils, rat poison, windshield wiper fluid, weed killers What factors create a reactivity hazard? - Correct Ans-peroxide-forming chemicals, water-reactive chemicals, self-reactive chemicals, incompatibility. What is corrosivity? - Correct Ans-chemicals that can cause tissue damage (permanent bodily harm to the skin, eyes or respiratory tract) What are the routes of exposure for chemicals? - Correct Ans-Inhalation, injection, absorption, ingestion What are the characteristics of a permit required confined space? - Correct Ans-A possibly Hazardous Atmosphere, the possibility of Engulfment, Internal Configuration that could trap and asphyxiate an entrant, contains any other recognized health hazard What is the difference between 25% oxygen and 100% oxygen? - Correct Ans-Neither are suitable for work, but 25% is an increased fire risk and 100% can cause brain damage What are all 7 steps of LOTO procedure? - Correct Ans-1. Identify potential hazards 2. notify all affected employees CWEA CWEA 3. turn off/disable/isolate controls 4. Lock out all energy control switched (sign and date!) 5. Test by turning on controls and accounting for personnel before the safety test 6. turn control to OFF 7. Perform task (when complete, only the person who tagged out may remove the lock and tag) What is the difference between a trench and an excavation? - Correct Ans-A trench is an excavation! Trenches specifically are deeper than they are wide, have a bottom width of 15 feet or less and have a higher potential for wall cave in. Excavations are any man-made work-related functions affected by earth removal or disturbance (i.e. cuts, trenches or deprsions) What is the "pipe zone" in the trench? - Correct Ans-the portion of the excavation where the pipe is located. What is the "haunch zone" of an excavation? - Correct Ans-Either side of the arched section in the bottom half of the pipe What type of equipment should be used to excavate a broken sewer pipe? - Correct Ans-Backhoe Name and describe the three soil types - Correct Ans-Type A: cohesive soils like clay Type B: Cohesive soil that have been disturbed or angular gravel Type C: Granular Soils like sand. These are the least stable What three steps can prevent harm to you whole in a trench? - Correct Ans-1. Find the competent person 2. Work in protected areas 3. Check your escape What are some factors that can make soil unstable? - Correct Ans-Excessively wet, Loose, Excessive roots What are the maximum allowable slopes or all the soil types? - Correct Ans-Type A: 3/4:1 Type B: 1:1 Type C: 1.5:1 What are some advantages of hydraulic shoring systems? - Correct Ans-They are light enough to be installed by one worker: from top down They are gauge-regulated to ensure even distribution of pressure along the trench line They can have their trench faces "preloaded" to use the soils natural cohesion to prevent movement CWEA They can be adapted easily to various trench depths and widths What are the components of a temporary traffic control? - Correct Ans-Traffic space that allows traffic to pass by activity, temporary lanes with a 10' minimum width and a 5' clearance from the excavation, and tapers that are used in the transition area and moves traffic out of its normal path. What is the minimum length of a taper in a temporary traffic control setup? - Correct Ans-50' How high do your traffic cones need to be if the speed limit around your work zone is 35 MPH? - Correct Ans-18". Cone height must be 18" if speed limit is 30 MPH or less and 28" if the speed limit is 45 MPH or more how many flaggers are REQUIRED to perform a basic flagging operation? - Correct Ans-one CWEA