WATER DISTRIBUTION OPERATOR PRACTICE EXAM 3 KEN TESH QUESTIONS & ANSWERS

Which device measures the hydrogen ion activity in a solution? - Answer PH Meter What is the purpose of a shaft sleeve in a centrifugal pump? - Answer Protects the sleeve from damage What is a nutating disc - Answer Type of water meter for small diameter domestic service what will happen to a steel pipe if the water has low PH? - Answer Corrode ___________________is a disinfection by product precursor - Answer Natural organic matter One of the requirements of the Lead and Copper Rule is for water systems to_____________if the action levels for lead or copper are exceeded (Based on 90th percentile of tap water samples) - Answer Install corrosion control If chlorine was added to water but there is no chlorine residual, which statement is true? - Answer Chlorine demand has not been met Which of the following is a parasite and microbiological contaminant? - Answer Giardia What can be used to control scaling, but can never be used to control corrosion? - Answer Sequestering Most regulated contaminants in drinking water? - Answer Only cause health effects after long term exposure What is the only MCL that varies with the temperature? - Answer Fluoride According to the Surface Water Treatment Rule, water systems serving a population of more than 500 persons must sample the filtered water for turbidity every? - Answer Every Four Hours The proper emergency kit for a TON chlorine cylinder is? - Answer Kit B The Surface Water Treatment Rule requires that disinfectant residuals be collected at the same location in the distribution system as? - Answer Samples tested for Coliforms What is the minimum separation for an Air Gap? - Answer 1" The middle layer is a reservoir is? - Answer Metalimnion. Also called the thermocline Pollutants in water? - Answer Are a low hazard and effect water aesthetics Water mains that are 12" or less in diameter should have isolation valves that are located not more than how many feet between each other? - Answer 1,000' All consumer water meters must test within what range of accuracy? - Answer Within 1.5% Over or Under Which of these is a displacement meter, which measure flow by registering the number of times that the meter chamber is filled and empty? - Answer Piston & Nutating Disc Meters If a water main can not be installed at an adequate depth to prevent freezing, Styrofoam insolation board can be used to protect the water in the pipe from freezing. How far above the pipe does the Styrofoam insulation need to be installed? - Answer 2-4" The proper emergency kit for a 150lb chlorine cylinder is? - Answer Kit A The sensors that respond to liquid pressure will perform poorly if what enters the sensor? - Answer Air The EPA recommends water systems using surface water to collect samples for hexavalent chromium (chromium-6) on what basis? - Answer Quarterly basis How much deeper below the grade line of a pipe bottom should a trench be excavated if it is being dug in a rock formation? - Answer 6-9 inches A split case pump has three impellers. What type of multi stage pump is that? - Answer Two Stage Records on bacterial analysis should be kept for a minimum of? - Answer 5 Years