Welcome to your Water Treatment Practice exam! Make sure to fill in all fields before submitting. What term describes the chemical capacity of water to neutralize acids? Acidity Alkalinity Hardness pH What should be the sample volume when testing for total coliform bacteria? 100 ml 250 ml 500 ml 1,000 ml What is the major health risk of nitrates? Nervous system damage Methemoglobinemia Colon cancer Gastrointestinal effects The secondary standard for iron recommends that the concentration not exceed? 0.61 mg/L . 0.41 mg/L 0.30 mg/L 0.50 mg/L Monitoring and control equipment often communicate with the SCADA system via? 4-20 mA signal Fiber optics Internet Lan line According to the EPA, sedimentation is based on a theoretical detention time of? 30 minutes 4 hours 1 day 8 hours For public water systems using surface water and groundwater under the influence of surface water, turbidity must be monitored at least? Hourly Every 12 hours Daily Every 4 hours Four-log removal for viruses is? 99.90% 90.00% 99.99% 99.00% An increase in which of the following causes the chlorine demand to increase? Organic matter Alkalinity Phosphate concentration pH The Total Coliform Rule is based first on? Type of coliforms in a sample Density of coliforms in a sample Presence of fecal coliforms in a sample Presence or absence of coliforms in a sample Sodium thiosulfate is used to? Buffer chlorine solutions Neutralize chlorine residuals Sterilize sample bottles Disinfection What is the causative organism for cholera? Vibrio Shigella Yersinia Mycobacterium Fusible plugs on chlorine cylinders are designed to melt at approximately? 80°F 195°F 100°F 158°F Daily consumption of gaseous chlorine may be checked by____________ Chlorine residual Platform scale Chlorine demand Chlorine dose Small gaseous chlorine leaks in and around a chlorinator can be detected by the use of commercial strength? Soda ash Nitrogen Lime Amonnia The proper emergency repair kit for a ton chlorine cylinder is an__________ Emergency kit A Emergency kit B Emergency kit C Emergency kit D Water system security is whose responsibility? Management EPA Everyone at the plant Police The secondary contaminant limit for fluoride is? 1.0 mg/L 2.0 mg/L 3.0 mg/L 4.0 mg/L An operator hears a pinging sound coming from the pump. What is the probable cause? Descaling Cavitation Corrosion Hardness The component of a centrifugal pump sometimes installed on the end of the suction pipe in order to hold prime is the? Casing Impeller Lantern ring Foot valve When taking a routine Bac-T sample, the sampler should also check what? Coliforms pH Chlorine Lead Lead and Copper are both based on? Positive Standard MMCLS 90th percentile action levels Presence-absence What are the two main causes of hardness in water? Lead & Copper Sodium & Phosphate Calcium & Magnesium Phosphate & Nitrate What device measures the flow rate of gases? Parshall flume Float Rotameter Weir What is the most common method used in labs to test for Total Coliform and E coli? DMA Colilert Autoclave NTU Coagulation occurs during the first? 1 to 5 seconds 10 to 20 seconds 30 to 60 seconds 61 to 180 seconds What precipitate is formed in alum coagulation? Complex compounds Aluminum Complex sulfate-compounds Aluminum hydroxide Records for bacteriological analyses should be kept for a minimum of? 5 years 7 years 10 years Indefinitely Which of the following chemicals is not listed as a trihalomethane? Bromodichloromethane Tribromomethane Sodiumomethane Dibromochloromethane pH is a measure of? Waters ability to neutralize acid Conductivity Dissolved solids Hydrogen ion activity What effect will algae in a reservoir have on dissolved oxygen (DO)? Lower the DO during the day and increase the DO during the night Slowly increase the DO during both the day and night Increase the DO during the day and lower the DO during the night Slowly decrease the Do during the day and lower the DO at night The amount of water in a water-bearing formation depends on the? Depth of the wall Porosity of the formation Size of the pump Type of well casing A filter should be backwashed when it has? Head loss Solids loading Influent turbidity Chlorine demand One volume of liquid chlorine gas will expand at room temperature and pressure, to occupy how many volumes of gas? 16 volumes 46 volumes 460 volumes 1660 volumes Surface water systems must treat, at a minimum for? Coliform bacteria and residual chlorine Coliform bacteria and turbidity Residual chlorine, turbidity, and pH Residual chlorine and Giardia What metals are most likely to leach from household plumbing and cause a health hazard? Iron & Zinc Iron & Copper Iron & Lead Lead & Copper What laboratory device sterilizes laboratory apparatus and microbial media by using pressurized steam? Hot plate Aspirator Autoclave Membrane filter Records on turbidity analysis should be kept for a minimum of? 5 years 7 years 10 years None of the above The filter rate and backwash rate of each filter shall be determined and recorded once each__________ week. month. quarter. year. The culture media used in the presumptive test is of _____________ agar. a nutrient agar. a brilliant green lactose bile broth. a lactose or lauryl tryptose broth. Fish eyes are _____________ undissolved clumps in solution. the primary cause of floc carryover. spots of coagulant attaching to the sides of the basin. None of the above. Water may be aerated by several methods, almost all of which involve_____________ covering the storage facilities. exposing a large surface area to the atmosphere. increasing the pressure. reducing its temperature. All chlorine cylinders are required to contain at least one fusible metal safety device (plug), how many does a 1-ton cylinder have? 2 3 4 6 The detention time usually required in a conventional straight-flow sedimentation basin is _______ h. 0.5 - 1 2 - 6 10 - 12 24 Air binding is a condition that may occur as a result of _________ filter-bed compaction. gravel displacement. negative head. reaching terminal head loss. A program for the control of algae should be instituted__________ on a seasonal basis. during extended periods of warm water temperatures. . after trend information has been established and adequate monitoring is practiced. on a routine, periodic schedule, but not to exceed two applications per year. With the coming of winter, the water temperature drops. A likely operational problem at a filtration plant with coagulation is ___________ odor. high alkalinity. high chlorine residual. floc carryover from the sedimentation system. The most desirable place to feed activated carbon in a lime-soda ash softening plant is_________ after lime feed. in the clearwell. to raw water at earliest stage possible. None of the above. A fluoride saturator____________ is suitable for small water systems. eliminates the need for a metering pump. eliminates the need for chemical handling. can only be used by large treatment facilities. Activated alumina is used effectively for the removal of_____________ humic substances. oxidized precipitates. herbicides and pesticides. certain inorganic elements. What state do you live in? Have a question? Idea? Use the comment box below. Email Name Time's up