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Distribution systems are usually laid out in which of the following patterns besides Tree shaped and Grid designs? a. Loops and/or circular designs b. Vertical designs without backflow prevention devices c. Horizontal lines that flow into open ponds then back into a closed pipe d. Horizontal lines that flow into underground sumps then back into a closed pipe - โโa. Loops and/or circular designs Dead ends in a system are usually located on a. Loops and/or circular designs b. Tree shaped and Grid designs c. Oval designs d. transmission mains e. Cul de Sac's with return lines - โโb. Tree shaped and Grid designs An operator may refer to Piezometric elevation, static head, or pressure head as a. horizontal water elevation b. water pressure from a pump c. maximum pressure from a fire hydrant d. vertical water column height - โโd. vertical water column height A downstream closed sectionalizing valve without pressure reducing valves in the system will have which of the following pressures placed upon it? a. the water surface elevation from the last point where the water is open to the atmosphere b. the back pressures from a downstream point c. the downstream booster pump operation
d. the operation of a fire hydrant located immediately downstream of the hydrant - โโa. the water surface elevation from the last point where the water is open to the atmosphere What is the main purpose of a water storage facility? a. to allow storage reserve during wet periods b. to help maintain adequate pressures throughout the entire system c. to meet needs for fire protection d. to provide sufficient amount of water to average or equalize the daily demands plus provide minimum pressures to fight fires - โโd. to provide sufficient amount of water to average or equalize the daily demands plus provide minimum pressures to fight fires Electrical demand in a wiring system is determined by the amount of a. Ohms in the entire system b. Voltage a system draws c. Watts consumed d. water pressure in the system - โโc. Watts consumed Baffling inside a storage facility may be needed to prevent "hot spots" and a. straight through flows b. long contact times with disinfectants c. high chlorine residuals throughout the facility d. high temperatures throughout the storage facility - โโa. straight through flows Chlorine may be added to water in a continuous, slug, and/or the _______ method to initially disinfect a pipeline? a. segmented b. tablet c. low dose d. air injection - โโb. tablet
d. surface waters are usually harder and more difficult to recover - โโa. groundwater takes longer to recover after contamination What constitutes a cross-connection? a. a connection between an approved and an unapproved water supply b. an unprotected connection between a drinking water supply and a system not approved as safe c. a connection between a contaminated supply and non-potable supplies d. all of the above - โโa. a connection between an approved and an unapproved water supply According to the Center for Disease Control (CDC), which mechanism or problem has caused more waterborne disease outbreaks (WDO) in the United States than any other reported factor? a. inadequate O&M of filtering systems b. lack of chlorination c. wellhead protection d. leaking backflow prevention equipment - โโd. leaking backflow prevention equipment What type of meter is used when the water flow widely fluctuates? a. Nutating-disc (nodding) meters b. Compound meters c. Proportional meters d. Venturi meters - โโb. Compound meters What are the basic requirements for an acceptable meter installation? a. leakage rate kept to a minimum b. always be in the public's view c. position in a horizontal plane, not tilted d. be inaccessible for service and inspection e. hid behind a fence near dog confinement areas - โโc. position in a horizontal plane, not tilted
How can mechanical damage to water meters be avoided? a. Placing the meter behind the curb and in a meter box b. Place the meter on top of a hydrant c. Grow shrubs around the meter d. Hide the meter behind an electrical utility pole - โโPlacing the meter behind the curb and in a meter box Which of the following is a displacement meter? a. Venturi b. Piston c. Compound d. Sonic meter - โโb. Piston The C-Factor relates to a. a factor used to indicate the smoothness of the interior of a pipe b. the elevation of the invert of a pipeline c. a line that represents the elevation of energy head of water d. a water service shutoff valve - โโa. a factor used to indicate the smoothness of the interior of a pipe Which of the following is an advantage in using centrifugal pumps? a. Air leaks on the suction side b. Limited suction lift c. Cannot self prime d. Easy to repair - โโd. Easy to repair When residential water meters become worn, they have the tendency to a. over-register all flows b. under-register all flows c. under-register small flows
a. copper sulfate b. chlorine tablets c. sodium thiosulfate d. hydrochloric acid - โโc. sodium thiosulfate The primary purpose of disinfection of water mains is to a. kill disease causing organisms in the water, if present b. sterilize the water main c. create a chlorine taste and odor d. keep the inside of the main clean - โโa. kill disease causing organisms in the water, if present Liquified chlorine gas will expand _______ times its original volume a. 25 b. 90 c. 200 d. 460 - โโd. 460 Chlorine gas is _____ times heavier than breathing air a. 2. b. 20 c. 60 d. 460 - โโa. 2. Chlorine gas is considered to be 100% pure, bleach is approximately 5 ยผ % pure, while HTH dry powder chlorine is set at _____ % purity. a. 20% b. 45% c. 65% d. 80% - โโc. 65%
When a 150-pound chlorine cylinder fitting slightly leaks around the gasket material, a gauze like material soaked in _______ should be used below the fittings to confirm the leak at the joint. a. chlorine dioxide b. sodium thiosulfate c. ammonia water d. oil - โโc. ammonia water A commonly used method to test for chlorine residual in water is called the _____ method. a. HTH b. THM c. VOC d. DPD - โโd. DPD As the pump shaft protrudes through the pump case, a mesh ring can be placed and compressed to prevent excessive leakage. This ring is commonly called the a. mechanical ring b. packing ring c. free ring d. bearing ring - โโb. packing ring When chlorine gas is added to water the pH goes down due to a. chlorine gas producing caustic substances b. two base materials that form c. two acids that form d. caustic soda being formed in the water - โโc. two acids that form Water with a pH of 7.9 is considered to be a. acidic
Horsepower is defined as ______________ ft-lbs per minute or 746 watts a. 8. b. 0.785 D c. 33, d. 43,560 - โโc. 33, The rated flow of a water meter, as stated by the manufacturer, is based upon which type of flow? a. intermittent b. short-time peak c. continuous d. the maximum capacity at peak flow - โโc. continuous What is the minimum setback distance for fire hydrants to avoid large vehicle overhang? a. 1 ยฝ - feet b. 2-feet c. 3-feet d. 3.5-feet - โโb. 2-feet The primary reason for using dry barrel fire hydrants is to a. allow easy maintenance of the hydrant b. prevent water hammer c. keep the barrel from rusting d. keep the barrel from freezing in cold weather - โโd. keep the barrel from freezing in cold weather Wet-barrel hydrants a. have slide gate main valves b. have main toggle valves
c. have standard compression main valves d. do not have main valves, but separate nozzle valves - โโd. do not have main valves, but separate nozzle valves When taking a storage facility out-of-service you must: a. recycle all metal b. build another storage facility c. coordinate and plan the shutdown, so that the distribution system will be able to meet customer's demands d. build up the water pressure and save it - โโc. coordinate and plan the shutdown, so that the distribution system will be able to meet customer's demands The three main components of a centrifugal pump are a. propeller, motor, and wiring harness b. wear rings, lantern rings, and volute c. impeller, case, and shaft d. shaft, wear rings, and AC power connection - โโc. impeller, case, and shaft Below ground storage tanks are vulnerable in having which of the following? a. high pressures within the tank b. insects and root damage c. sunlight penetration that reduces chlorine residuals d. high total dissolved solid content - โโb. insects and root damage The pipeline flushing process tends to remove most deposits, encrustations, sediments and other debris. Customers should be notified to expect _________ after the flushing operation is completed. a. a residual amount of sediment coming into the dwelling for at least a few hours, so it would be best to flush their own lines when noticed b. hot water c. pure water d. to boil their water for at least one-week - โโa. a residual amount of sediment coming into the dwelling for at least a few hours, so it would be best to flush their own lines when noticed
