Class "C" Water Exam Questions with Complete Solutions 2023/2024 A common chemical used in the disenfection of a small water supply is- - Correct Answer Calcium Hypochlorite A physical connection between a potable water supply and a house well would be- - Correct Answer A Cross Connection The amount of Chlorine in mg/L that is used by reacting with iron, organics, or bacteria is called? - Correct Answer Demand All of the following are Physical characteristics of Chlorine gas- - Correct Answer Greenish Yellow color Heavier than air Pungent, Penetrating odor Corrosive Which of the following would be considered a part of a hypo-chlorinator system? - Correct Answer Solution feed pump According to state requirements, all public water supply wells should be provided with a raised concrete sealing block, screened vents and- - Correct Answer Flow measuring device The drawdown of a water well is determined by- - Correct Answer The difference in static and pumping levels The pH of water indicates- - Correct Answer If it is more acidic or base The pH of water is expressed by a scale of numbers ranging from- - Correct Answer 0- 14 Water that is considered neutral is expressed on the pH scale at- - Correct Answer 7.0 Which of the following is a required step in collecting a routine distribution sample for bacteriological testing? - Correct Answer Use of an approved, sterile container Sand filtration will remove which of the following from surface water? - Correct Answer Turbidity Activated Carbon is used in a Surface Water Plant primarily for? - Correct Answer Taste and Odor control 1 / 2
Which of the following chemical(s) are commonly used as coagulants in surface water treatment? - Correct Answer Alum and Ferric Chloride Ground storage tanks are required to be provided with which of the following? - Correct Answer Screened Vents An approved locking roof hatch An overflow pipe with hinged flap device Annual inspection and maintenance as needed An elevated storage tank should be protected against corrosion by- - Correct Answer Painting Cathodic protection Water stabilization A public water supply system should maintain residual pressure of 20 psi and a minimum normal operating pressure of- - Correct Answer 35 psi Before a new or repaired water line is placed into service, it must be properly disinfected by providing a chlorine dosage of _____ and proper detention time. - Correct Answer 50 mg/L Water bearing formations beneath the earth's surface that are used as a source of water for public water supplies are- - Correct Answer Aquifers The purpose of an air line on a well is- - Correct Answer Determine water levels in the well The mesh size is an important feature of a well screen because property sized openings should- - Correct Answer Reduce the amount of sand pumped When treating surface water, the process of coagulation will be most affected by the- - Correct Answer pH, alkalinity, temperature, and chemical dosage A rapid sand filter should be backwashed when- - Correct Answer When the loss of head gauge indicated between 6 and 10 ft.Which of the following is an acceptable disinfection residual at the far reaches of the distribution system- - Correct Answer 0.2 mg/L free chlorine residual 0.5 mg/L chloramine residual for a surface water supply 0.8 mg/L chloramine residual when using chloramine treatment 0.5 mg/L free chlorine residual for a groundwater supply One gallon of water weighs- - Correct Answer 8.34 lbs One foot of water inside a storage vessel will raise a pressure gauge at the bottom of the vessel by- - Correct Answer .433 lbs
- / 2