WSO Water Treatment Grade 2 Practice Test

These questions are part of the practice quiz. Start practicing

• Which processes are used to remove particles from surface water?
• What is pressure measured in terms of the height of water referred to as?
• Which process increases the temperature of the water when quick lime is added?
• What is the filtration rate in GPM/ft² if a filter that is 24 ft by 28 ft receives a flow of 3,250 GPM?
• What is typically assessed during a turbidity test?
• Which regulation promotes routine surveillance of water quality to detect fecal contamination?
• If the natural fluoride content of raw water is variable, how often should it be measured?
• When using four packing rings, how should they be staggered?
• What is the Maximum Contaminant Level (MCL) for haloacetic acids (HAA5)?
• How often must treatment plants conduct solids retention analysis?
• What type of control features a controller that continually adjusts output in response to deviations from the set point?
• Which type of aerator is more efficient in removing dissolved gases and oxidizing iron and manganese?
• What is the purpose of collecting distribution system samples?
• After which treatment step should the fluoride injection point be located?
• Why is it important to catalog data from customer complaints?
• What is another term for the service cycle (relating to ion-exchange softening)?
• What type of system includes both localized and uniform corrosion?
• Which system is known as the first type of underdrain system with a central manifold pipe?
• What type of sample consists of multiple grab samples combined into one sample for analysis?
• What is a key disadvantage of using a confined aquifer for water supply?
• Which type of sludge could block a sanitary sewer system if discharged?
• Which unit of measurement is typically used for flow rate in water treatment?
• What type of pump features a water inlet at one end and a discharge opening at a right angle?
• What regulation mandates online turbidimeters in surface water treatment plant filters?
• What is the simplest form of automation in a chlorinator system?
• What is the Maximum Contaminant Level Goal (MCLG) for suspected carcinogens?
• How often should chemical levels be checked in the saturator?
• Which factors can only be determined by a human operator in plant operations?
• How does chlorine gas behave in a fire situation?
• What element in source water acts as the precursor to disinfection by-product production?
• What is a major concern regarding chlorine as a disinfectant in water treatment?
• What is the major cause of short-circuiting in a sedimentation basin?
• What force is responsible for pulling particles together in the coagulation-flocculation process?
• What is the minimum disinfectant residual that must be maintained in water served to a population greater than 3,300 for no more than 4 hours?
• Which type of valve is used to prevent backflow in a pump system?
• What is the purpose of staggering the packing rings in a pump?
• What is the maximum time recommended to wait before analysis of coliform bacteria samples?
• What is a sedimentation bowl that rotates at high speeds to separate sludge from water by centrifugal force called?
• Once the ion exchange resin can no longer remove hardness, it is said to be:
• What reporting schedule do most state regulatory agencies require for water plants?
• Raw-water temperature that approaches the freezing point has what effect on coagulation and flocculation processes?
• Water is drawn into a water supply system from a surface impoundment or stream through:
• What is a common method for testing water for coliform bacteria?
• Before entering a permitted confined space, what must be tested?
• What device is typically required to hold water temporarily after aeration or addition of an oxidant?
• By how many days must compliance testing results be reported after the end of the month?
• What is the formula for calculating the area of a circle?
• What is the common construction type for filter tanks?
• If a spherical tank is 20 ft in diameter, what is its capacity?
• How often does the Partnership for Safe Water recommend turbidity performance be recorded?
• What factor is crucial in determining the effectiveness of sedimentation basins?
• How many total atoms of oxygen are present in Ca(HCO₃)₂?
• Which regulation limits human exposure to harmful organisms like Cryptosporidium?
• Why is soda ash needed in the treatment of water?
• Block salt is sometimes used for home softeners, but it is not suitable for larger installations because:
• Process recovery in membrane treatment for surface water typically ranges from what percentage?
• What is the purpose of an evaporator in chlorine treatment?
• Ferric sulfate has which advantage over aluminum sulfate (alum)?
• Which treatment method is often faster than traditional methods?
• Which gas produced by certain bacteria can accelerate the corrosion process?
• How is velocity head mathematically expressed?
• What is the most important reading usually taken in a treatment plant?
• Which metal is the most likely to corrode?
• Which condition can adversely affect the efficiency of flocculation processes?
• What is a common mistake that operators make in regards to flocculation units?
• Which type of algae would most likely be found in nutrient-rich waters?
• What are the three objectives when responding to customer complaints?
• Jar test results are expressed in:
• What is the best policy when communicating with the media?
• What process can be used to remove water from sludge?
• Under the Surface Water Treatment Rule, where must disinfection residuals be collected?
• Which type of continuous control maintains action when the signal is lost?
• What happens to PAC particles when they are coated with coagulants or other water treatment chemicals?
• What factor influences the classification of public water systems into categories?
• Sequestration for iron and manganese is effective in groundwater that has what characteristic?
• In the event of a substantial chlorine leak, which agency should be contacted for assistance?
• The pressure in a chlorine cylinder depends on what factor?
• _____ aerators draw water into the blade of the aerator and throw water into the air in tiny droplets.
• What device compresses tightly around a pump shaft by applying even pressure?
• Should rainwater be considered pure?
• In calcium hydroxide (Ca(OH)₂), how many atoms of hydrogen are present in one molecule?
• Which of the following is a component of a lantern ring?
• What type of hardness is treated by adding lime?
• Manganese greensand filters can be regenerated by using what solution?
• In situations where raw water constituents interfere with the preoxidation/filtration process, which type of regeneration is preferred?
• Which type of well is commonly used near the shore of a lake or near a river to obtain a large amount of relatively good-quality water from adjacent sand or gravel beds?
• What is powdered activated carbon primarily used to control?
• What are the two broad classes into which corrosion in water systems can be divided?
• What approach has the Department of Homeland Security adopted for enhancing preparedness against various threats?
• What is one disadvantage of using ozone in water treatment?
• Which type of wells are commonly used near the shore of a lake or near a river?
• When backwashing an ion exchange unit, how much should the bed expand from water introduced from the bottom of the ion exchange column?
• What is the term for a conical tank used for rapid softening reactions?
• What are cations?
• How is volume calculated in the volume formula?
• In a slate-and-coke-tray aerator, sloping sides that protect against splash losses are called what?
• What is a significant advantage of using ozone as an oxidant?
• Chlorine cylinders and ton containers are equipped with valves that must comply with standards set by which organization?
• What type of data is essential for assessing long-term system performance goals?
• An artesian aquifer could occur in a(n):
• Which compound formed from chlorine can be harmful to health?
• What is a consequence of inadequate fluoride measurement during water treatment?
• What is the maximum weir loading for light alum floc in solids-contact basins?
• What is the maximum head that a double suction pump can reach?
• What is the most cost-effective method for transporting sludge to lagoons?
• Which device(s) uniformly disperse(s) the chlorine solution into the main flow of water?
• What does the multiple-barrier approach in surface water treatment systems involve?
• C × T values are influenced by which factors?
• Zebra mussels multiply and spread so fast because:
• Diatomaceous earth is derived from which prehistoric source?
• A solution is made up of a solvent and which other component?
• When a water sample is acidified, what must be the final pH level?
• To prepare 25 gallons of a 2 percent strength solution, how many pounds of chemical are needed?
• The lower the _____, the more difficult it is to form a proper floc.
• Which of the following is a mechanical measuring device?
• What does the Partnership for Safe Water suggest be recorded periodically in each sedimentation basin?
• What is defined as the number of equivalent weights of solute per liter of solution?
• Division of water into three layers, each of a different temperature, is referred to as:
• The quantity of dissolved oxygen in water is a function of:
• Who is responsible for verifying that all conditions are in place before entry into a confined space?
• Which of the following is not a method of controlling corrosion?
• Which chemical compound primarily contributes to scale formation within pipes?
• Which filter component is critical for supporting percolation in a sand filter?
• What issue could gravel displacement in a filter bed from rapid backwash cause?
• Which element is critical to monitor for maintaining safe water conditions in a distribution system?
• What effect can pollutants in rainwater have on water quality?
• What is the best type of salt to use in the regeneration of ion exchange softener resin?
• What is the rationale behind the three categories of public water systems?
• Which type of filter is designed to remove iron and manganese through adsorption and oxidation?
• A safety data sheet is required for which type of chemicals?
• Ion exchange processes can typically be used for direct groundwater treatment as long as turbidity and _____ levels are not excessive.
• What is the primary risk associated with chlorine gas in emergency situations?
• Conventional sedimentation has a _____ removal of Cryptosporidium oocysts.
• How would you define the water table?
• What device is used to prevent air from entering a pump due to insufficient packing tightness?
• Which variables primarily affect the operation of gravity bed thickeners?
• According to what authority should metering pumps receive routine maintenance?
• When should fluoride levels be measured to test for fluoride concentration during the addition process?
• What can excessive flocculation lead to in a treatment process?
• Which type of control system allows for adjustments based on varying water pressure?
• How many gallons are in one cubic foot?
• Corrosion can occur in water treatment systems with which of the following?
• Which type of chlorine gas feeder is most commonly used in water treatment?
• What is an injector?
• What is a key advantage of a confined aquifer?
• What should be done immediately after repairing a small chlorine gas leak?
• Under the process safety management regulations, when is a site assessment required?
• What is the standard duration for maintaining a minimum supply of water treatment chemicals?
• What is the best chemical to use for corrosion inhibition in water that is low in alkalinity and calcium concentration?
• What is an example of benchmarking in water quality monitoring?
• What type of sample is necessary to determine the presence of coliform bacteria?
• Stabilization in water treatment is primarily used to control which issue?
• Where should chlorine cylinders be stored?
• What characteristic of water is increased through successful spray aeration?
• What does the Langelier Saturation Index measure?
• What index is used to determine the calcium carbonate deposition property of water?
• If newly installed manganese greensand is not skimmed of fines after backwashing, what is the immediate consequence?
• Which chemical is an effective oxidant for controlling iron and manganese, as well as addressing taste and odor issues?
• What is the detention time in hours for a clarifier with an inner diameter of 112.2 ft and a water depth of 10.33 ft if the flow rate is 7.26 MGD?
• Which coagulation testing method is known to be the most useful tool for operators in water treatment?
• If high-quality water is applied to filters and run times are long, what problem might arise?
• What is the first step in calculating the percent by weight of an element in a compound?
• In lime softening facilities, what is the recommended minimum storage time for each chemical?
• In a slurry feed system, day tanks are typically made of what material?
• What term refers to a series of treatment steps that are redundant in their ability to remove contaminants?
• What is the minimum height of chemical that should be maintained in the saturator at all times?
• What is considered the most economical sludge disposal method for lime-soda ash softening plants?
• What is the chemical formula for calcium carbonate?
• How should burning carbon be handled?
• Where are the sampling point(s) located for required sampling of turbidity in a community water system?
• Bored wells, constructed with an auger driven into the earth, are limited in depth to approximately:
• Dissolved-air flotation is particularly good for removing:
• Many streams would dry up after a rain if it were not for:
• According to the American Water Works Association, what is the recommended minimum supply of water treatment chemicals to maintain?
• What is a disadvantage of using a confined aquifer for water supply?
• What reports are essential for determining filter performance?
• How much water must be added to 80 mL of a 2.5N H₂CO₃ solution to achieve a 1.8N solution?
• What is the optimal pH range for removing particulate matter when using alum as a coagulant?
• A circumstance in which it is more economical or practical to provide treatment at the source versus in a water treatment facility is referred to as:
• GAC contactors can be used when the formation of trihalomethanes or other disinfection by-products cannot be prevented by what?
• What fluoride concentration in drinking water is likely to cause pitting in people's teeth?
• What term refers to the level of the water surface in the well when no water is being taken from the aquifer?
• How long can samples to be tested for coliforms be refrigerated before analysis?
• What substance can cause the consumption of lime when present in high concentrations in water?
• What is one potential outcome from performing a sieve analysis on media?
• What occurs at the bottom of a sedimentation basin as solids settle?
• What is the layer of solids and biological growth on a slow sand filter called?
• What is precipitated when magnesium hardness is treated with lime?
• In a typical air-scour sequence, when is backwash water introduced?
• What term describes the level of the water surface in an aquifer?
• What type of response does the all-hazards approach prepare for?
• What primary test is used to indicate proper sedimentation?
• Which type of aerator consists of a propeller-like mixing blade mounted on the end of a vertical shaft driven by a motor?
• What is the filtration flow rate through a high-rate mixed media filter?
• What is a significant consequence of a chlorine leak incident?
• What is an important characteristic of high-rate mixed media filters?
• In a slurry feed system, where should the feeder be located to avoid danger of settling?
• At the surface, all wells should have a sanitary seal, which prevents contamination from entering the:
• Compared to air, how dense is chlorine gas?
• What is often a consequence of sedimentation in water treatment?
• Weak-base anion exchange resins behave much like their weak-acid counterparts; they do not remove anions above what pH level?
• If a chemical metering pump is pumping 26.3 gal/day, how many mL/min is this?
• What is one key characteristic of a safety data sheet for chemicals?
• What is the main function of the pump shaft?
• Which regulation focuses on reducing the risk of fecal contamination in public water systems using groundwater?
• A plant operator determines the best flow by using which of the following?
• Which regulation requires surface water systems to maintain specific C x T values?
• In water treatment, what is the effect of increased water temperature on floc formation?
• Which material is manganese greensand, and which is the coating?
• What type of system is considered when assessing chlorine gas weight thresholds?
• Why is pretreatment with chlorine being eliminated in many water treatment plants?
• Which addition is needed to precipitate non-carbonate magnesium hardness out of water?
• In a precipitative softening plant, what percentage of solids is typically produced?
• What principle do particle counters operate on?
• Which type of aerator causes aeration to occur in splash areas and can help oxidize iron?
• What component most closely follows the cartridge filter in a typical reverse osmosis flow schematic?
• When evaluating treatment strategies for iron and manganese, compliance with which regulation is necessary?
• What is the effect of adding quick lime to water?
• In a drying bed, the usual depth of the sand layer is?
• What defines the ratio of produced product water to raw water treated?
• Which equipment maintenance is critical to ensure accurate chemical dosing?
• Destratification of a lake will often reduce:
• What is the term for raw water that has undergone pretreatment before entering membrane arrays?
• Which method is most effective in increasing the size of floc particles?
• What is carbon dioxide used for in the process of lime softening?
• How frequently should the fluoride concentration of treated water be measured?
• What is a requirement for chlorine gas storage rooms?
• Which of the following factors can affect chlorine residual in water systems?
• The primary function of couplings in a pump system is to transmit rotary motion from the motor to which component?
• What does molarity measure in a solution?
• What federal regulation requires that samples from customers' taps be analyzed for the presence of lead and copper?
• If enteric disease-causing protozoans have been found in the effluent of a water plant, which is the most probable solution?
• Because harmful bacteria do not penetrate very far into the soil, wells are generally free of harmful organisms if:
• Which index can indicate whether water will be corrosive or deposit-forming?
• At which temperature does the maximum density of water occur?
• Which type of continuous control requires elements like meters, transmitters, and transducers?
• Immediately below the water table is the:
• If 10 lb of H₂CO₃ is used, how many pounds of CaCO₃ will react?
• Is rainwater considered pure water?
• What is the normal air-to-water ratio at peak flow in a packed tower aerator?
• In the equation to convert milligrams-per-liter concentration to pounds per day, what does the feed rate equate to?
• What major consideration should be taken into account when starting and stopping large pumps?
• How is the water stabilized before filtration in lime softening?
• Which chemical is specifically used to remove residual chlorine from water?
• Which process is used to concentrate sludge in water treatment?
• What should be continuously monitored and recorded to control corrosion as water enters the distribution system?
• Which organization issued the Risk Management Rule to protect public health and safety?
• If fluoride is added before filtration, what is a potential consequence?
• What is the typical backwashing flow rate for a manganese greensand filter bed, depending on water temperature?
• What is the term for the maximum concentration of a contaminant that is allowed in drinking water?
• What method can effectively extend the length of filter runs for manganese greensand filters?
• What is the primary purpose of disinfection in water treatment?
• What is the main purpose of using coagulants in water treatment?
• How much time is required to develop heavy floc particles during the flocculation process?
• In what process is calcium carbonate formed?
• In a rectangular basin, which type of collector uses suction pipes or submersible pumps for sludge withdrawal?
• To reduce non-carbonate hardness in water, soda ash must be added to form:
• What is the action level for copper in drinking water?
• Which type of centrifugal pump impeller is suitable for pumping medium-sized solids?
• What conventional treatment step is bypassed in direct filtration?