Water Distribution Questions and Answers with Certified Solutions

Water Distribution Questions and Answers with Certified Solutions Potable water may be defined as: a. Any water that occasionally may be polluted from another source b. Any water that, according to recognized standards, is safe for consumption c. Water high in organic content d. Water that has been transported from outside the service area b). Any water that according to recognized standard is safe for human consumption. To prevent the entry of surface contamination into a well is the purpose of: a. The well casing b. The louvers or slots c. Well development d. The sanitary seal d) The Sanitary Seal Pure water will exhibit a pH value of? a. 0.0 b. 7.0 c. 10.5 d. 14.0 b) 7.0 A pH reading of 6.0 units indicates that the water sample is: a. Very acidic b. Slightly alkaline c. Very alkaline d. Slightly acidic d) Slightly Acidic In drinking water quality, "TDS" is the abbreviation for? a)Total digestable substances b) Total dissolved solids c) Time-delayed sicknesses d) Terminal diseases started b) Total Dissolved Solids In drinking water regulations, the abbreviation "MCL" stands for? a) Maximum contaminant level b) Multiple constituent levels c) Most common level d) Minimum considered legal a) Maximum contaminant level The MBAS method is used to determine levels of which of the following drinking water constituents? Forming Agent In water quality, the symbol "mg/L" is equivalent to: a. Micrograms per liter b. Parts per million c. Parts per billion d. Mostly good levels b) Parts per million The term "clearwell" refers to a? Reservoir at the outlet of a water treatment plant. A mechanical device often employed to prevent the over-filling and/ on over-draining of distribution system reservoir is the? Altitude Valve The primary cause of water quality deterioration in distribution system is? Water age The term "Springline" applies to? The midline of a pipeline When possible, a water main should be tapped while still pressurized to? Minimize contamination risk A connection made into a water main that is full of under pressure is called a? a. Cross connection b. Valve box c. Wet tap d. Spinal tap c) Wet tap A special valve that is used almost exclusively to facilitate making connections to pipeline is the? a. Gate valve b. Corporation stop c. Altitude valve d. Auxiliary valve b) Corporation Stop Which of the following gases will deaden the sense of smell? a. Carbon dioxide b. Hydrogen sulfide c. Methane d. Oxygen b) Hydrogen Sulfide The most commonly used meter on small domestic services? a. Venturi meter b. Propeller meter c. Orifice plate meter d. Nutating disc meter d) Nutating Disk Meter A Nutating disk is found in certain? a. Positive displacement pumps b. Main line valves c. Chemical feeders d. Water meters d) Water meters A pump is experiencing back-spin after it is shut down. What is the most likely cause? Malfunction check valve When fully open, which of the following valve types will have the highest friction loss? a. Gate valve b. Globe valve c. Ball valve d. All will have about the same friction loss. b) Globe valve The main purpose of a butterfly valve in a water distribution system is for? Isolation The most likely means of connecting two pressure zone is throug