WATER DISTRIBUTION OPERATOR PRACTICE EXAM 3 KEN TESH

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