Minnesota Class D Water Exam | 163 Questions and Answers(A+ Solution guide)

According to the Safe Drinking Water Act the basic definition of a public water supply system is any water system that supplies water for human consumption that serves: - 15 service connection or over 25 persons for over 60 days a year What federal law regulates public water supplies? - Safe Drinking Water Act What cause water to move through pores in soil and rocks ? - Gravity What are disease producing bacteria called? - Pathogenic A presence/absence coliform test utilizes - color change What are two main causes of harness in water? - Calcium and magnesium Which source of water has the greatest natural protection from bacterial contamination? - deep well in gravel Which of the following terms refers to excessive internal pressure which may be several times the normal operating pressure and can seriously damage hydropnematic tanks, valves, and piping network. - water hammer What are the two most important safety concerns when entering a confined space? - hazardous gases and oxygen deficiency what piece of safety equipement must an operator wear when entering a confined space? - Harness Which document provides a profile of hazardous substances? - MSDSWhat safety measure must ab operator follow prior to working on electrical equipment? - Lock out Tag out all electrical switches what is the correct procedure for mixing acid an water - Acid is ADDED SLOWLY to water The major source of error when obtaining water quality information is improper - Sampling Polyphosphates should be fed at which point? - Before the addition of chlorine After a new water main is installed and pressure is tested, it should be? - Filled with a solution of 25 ppm to 50 ppm free chlorine for at least 24 hours before flushing The minimum horizontal distance allowed between waterman and sanitary sewer is - 10 feet The health department requires a minimum of how much free chlorine residual at distant points of the ditribution system? - 0.2 ppm A PH reading of 2 means the water is: - Acidic vent openings on reservoirs and clear wells should be: - Screened How many pipe diameters should a meter be located in relationship to elbows or fittings? - Three pipe diameters upstream, five pipe diameters downstream chlorine leaks can be detected around a chlorine cylinder by the use of: - Ammonia