ADEQ Water Treatment 2 Practice Test

These questions are part of the practice quiz. Start practicing

• After a routine sample tests positive for total coliforms, which analyses are required?
• Which chemical used for oxidizing iron and manganese will react with hydrogen sulfide, cyanides, phenols, and other taste and odor compounds and will not form trihalomethanes?
• The Information Collection Rule is designed to support the development of which types of regulations?
• Which fires require a Class D fire extinguisher?
• Stage 2 Disinfectants and Disinfection Byproducts Rule uses sampling sites based on what evaluation approach?
• Although _______ can be added to lime-soda ash rapid-mix basins, better results are usually obtained if they are added _______ in a separate rapid-mix basin.
• When iron alone is treated using manganese greensand filters, the chlorine feed rate should be about ______.
• What pH level is required to precipitate magnesium hydroxide?
• The slime layer prevents deposition of calcium carbonate. When the slime sloughs away, it carries away which substance and leaves the pipe surface bare?
• Before making corrosion control changes, with which state authority should utilities coordinate first?
• The filtration ripening process is driven by which phenomenon?
• Unlike reverse osmosis and nanofiltration, the recovery of the microfiltration process is not limited by the formation of _____ or the precipitation of _____.
• Hardness has any unwanted health effects?
• Electrical conductivity meter readouts are in what units at what temperature?
• What should be used to clean an old bearing?
• Alkalinity definition and units
• Which measuring and transmitting level device works readily on a 4-20 mA system but needs a temperature correction?
• How often are the maximum daily temperatures determined to establish the optimal fluoride levels for any particular state?
• Equivalent weight is defined as the weight that will react with, displace, or is equivalent to one gram of hydrogen.
• The abbreviation LT2 stands for which designation?
• What is a potential concern when ozone is used as a primary disinfectant?
• After the Long-Term 2 Surface Water Treatment Rule testing, a system is put into a ________, which are ______ concentrations in the source water for the theoretical potential for contamination.
• In a two-stage recarbonation process, CO2 is added after lime to lower the pH to approximately which range?
• How is aluminum oxide activated?
• A specific-ion meter resembles a _______ except for the addition of a ______ and a provision for a selective-ion electrode.
• What information can particle counters provide about particles?
• Which contaminants make up the Contaminant Candidate List (CCL)?
• What piece of laboratory equipment can be made of polycarbonate and is clear, such that there is no confusion over reading the meniscus?
• What scale prevention chemical can loosen existing deposits and cause red-water complaints?
• Define divalent.
• A common problem with hyperchloronators is ________
• Gas chromatography-mass spectrometry is used to determine which category of compounds in a sample?
• If dissolved oxygen increases, the corrosion rate changes as well as the effect of increasing pH and alkalinity on corrosion rate.
• Which statement describes a common natural form of manganese (Mn) in soils and is not MnO?
• Point-of-use activated carbon filters are most effective for removing which contaminant?
• Driven wells are practical only when the water-bearing formations are relatively close to the surface and no contaminants exist in the soil. Which statement best describes this condition?
• Mineral acids are measured by titration to a pH of 4.3 using which indicator?
• What type of pretreatment settling units can use coagulants because it has been showing to be very effective?
• What is the chemical formula corresponding to caustic soda?
• What are glassy phosphates?
• Which arrangement describes lamella plate flow?
• Drinking water containing copper well above the action level will most likely cause _______.
• Chlorite is regulated under the _______ and has maximum contaminant level of ______.
• Which action is NOT recommended when working around machinery with moving parts?
• Minimum hardness achievable by lime-soda ash process
• Which unit correctly identifies the unit expressing electrical potential?
• Which regulation addresses backwash water recycling in filtration plants?
• Alternate statement about the cations usually present in water in significant concentration: Which ions are usually the primary hardness contributors in water?
• A low-cost radioactive scan is first done to determine if the level of radioactivity is high enough to progress to further analyses. The level of radioactivity that would call for further analysis is normally the ______ for ______ or _________ but can be varied by the particular state drinking water agency.
• When alum is added to water, it causes the pH to _______, and when ferric salts are added to water, it causes the pH to ________.
• What is a disadvantage of using chlorine dioxide in water treatment?
• Lamella plate or tube settlers with angles of ______ would require backflushing or manual cleaning to remove built-up sludge?
• Lime-soda ash softening can reduce water hardness to approximately which range?
• The flow through a sedimentation basin should not exceed
• An organic contaminant from coagulants would most likely include which compound?
• In the two-stage recarbonation process, the raw water pH is elevated to ____ or greater with lime; after that stage, carbon dioxide is added to lower the pH to ____
• When did the Long-Term 2 Enhanced Surface Water Treatment Rule take effect for large systems?
• If coliforms are present, the gas they produce will begin to form bubbles in each inverted vial within what period?
• Which organism obtains energy for growth from the chemical reaction that spontaneously occurs between iron and manganese and dissolved oxygen?
• Which factor is most commonly cited as the benefit of pressure filtration for small water systems?
• How can an operator accept responsibility for an active role in the safety program?
• What NSF/ANSI Standard covers coatings, construction materials, and components?
• What was the primary concern for why the Final Groundwater Rule was promulgated?
• What is the main purpose of presedimentation following screening?
• Why are cold-weather conditions an added hazard when working around water?
• The most common higher-rate filter media consists of the following (bottom to top)
• What is the purpose of turning off surface washers before the end of the backwash?
• What is the major reason that turbidity is undesirable?
• What is the Stage 1 Disinfectants and Disinfection Byproducts Rule maximum contaminant level for chlorite?
• The precipitative softening process uses which mechanism to render calcium and magnesium insoluble?
• Which source water is most likely to contain iron and manganese?
• Breathing hydrogen sulfide gas at low concentrations can be fatal. Which combination is listed as fatal?
• Which statement describes how aluminum oxide is activated?
• Ammonia is an inorganic compound occurring ______
• A gas chromatography-mass spectrometer would be used to determine ______ in a sample.
• The flow through a sedimentation basin should not exceed...
• In HPC testing, which plating incubation duration applies for plate-count agar?
• In the multiple-tube fermentation method, as presumptive positives are inoculated into BGB, 0.1 mL of presumptive broth is also transferred into which broth?
• When analyzing samples for haloacetic acids 5 (HAA5), what is added to the sample container to quench more HAA5 formation?
• A special problem with granular activated carbon filters is the rapid growth of which microorganisms?
• What byproduct is most associated with chlorine dioxide used for disinfection?
• A conical tank in which the softening reactions take place as the water passes upward through the unit is described as what type of reactor?
• Which genus has killed the most people because of its high mortality rate when contracted?
• Circuit breakers, compared to _______, have a much _______. This means that they are capable of interrupting the flow of considerably _____ than could be interrupted by _______.
• What loads are applied to a pump's shaft?
• What is a disadvantage of using caustic soda to soften hard water compared to other chemicals?
• Which substances serve as precursors to disinfection by-products when disinfectants are used?
• Carbonate alkalinity is caused by which ion?
• Under favorable conditions, combined chlorine, such as monochloramine and dichloramine, compared to the bactericidal action of free chlorine would require ____ times more combined chlorine residual.
• To determine a safe stopping distance behind the vehicle in front, you should consider
• What should be done to a shaft after an old sleeve is removed and before a new sleeve is installed?
• Which regulation requires performance goals for filters, data collection, and reporting exceptions for any filter not performing in accordance with the turbidity values stated in the rule?
• A special problem with granular activated carbon filters is the rapid growth of which microorganisms?
• The cleaning of microfiltration membranes helps maintain a stable ______ while keeping recovery at or above _______.
• Lamella plates work by
• After microscreening, there should be a significant reduction in _________.
• Which byproduct is formed when ozone is used for disinfection and is commonly monitored for public health protection?
• A treatment plant's effluent water quality would be best shown from a sample collected _____.
• Powdered activated carbon dosing: which feed system reduces handling problems?
• If the pH of a water sample increases, the calcium carbonate level will ________, and as the temperature increases, the solubility of the calcium carbonate ________.
• In a dual media filter, it is best to have ____ backwash rates because each type of media has a different ____.
• Which parameter is not part of the Langelier saturation index calculation?
• Which organization issued the Risk Management Rule in 1996 in an effort to protect public health and safety (nonemployees)?
• Powdered Activated Carbon (PAC) is used in water treatment to achieve removal of contaminants primarily through which mechanism?
• How often should amperage and voltage tests be performed on three-phase motors?
• The Langelier Saturation Index is used to assess the tendency of water to precipitate or dissolve calcium carbonate.
• The best way to remove H2S is by scrubbing at about _______ by bubbling CO2 through the water before aeration to reduce the pH
• What is hardness caused by?
• Dissolved air flotation has achieved a ______ removal of cryptosporidium, which compares to a removal rate of less than 0.5 log using conventional sedimentation.
• The Radionuclides Rule added for the first time an MCL, for uranium of ______
• An electric current in a wire travels from end to end at _______. However, individual electrons within the wire move ______ and over ________.
• The depth to which submerged plants will grow is primarily limited by ______
• Which of the following is not a part of a bearing?
• In the chemical precipitation process, the hardness causing ions are converted from [blank] forms. Calcium and magnesium become [blank] as the pH increases.
• What are the potential hazards when handling activated carbon?
• Bentonite clay improves coagulation by which mechanism?
• When can wearing gloves be a hazard?
• What are the three forms of carbonate hardness?
• The iodometric method is a variation of which method for dissolved oxygen determination?
• The solubility of calcium carbonate in water decreases as temperature increases.
• What does valence refer to in chemistry?
• Which alum sludge dewatering method can attain at least 20% solids by weight?
• Which source water type is commonly associated with iron and manganese presence?
• Synthetic organic compounds would more likely contain _____ than natural organic compounds
• Water becomes capable of _______ iron and manganese when the oxygen levels ________.
• What are the principal precursors that react with disinfectants to produce disinfection by products?
• In regenerating ion-exchange systems and lowering the pH of water treated by membrane processes, which chemical family is used?
• In the brine regeneration process, which cations are exchanged on the resin by sodium?
• Stage 2 DBPR compliance is evaluated at each monitoring location using which metric?
• During greensand regeneration, continuous regeneration is typically used while the filter is offline.
• Surface washers should be turned off ____ min before the end of the main backwash.
• The platinum-cobalt method measures which property in water?
• In the simplest terms, what is hardness?
• Which pairing of units correctly describes electrical energy and power?
• Which hazard pair is most associated with handling activated carbon?
• The regulatory framework that includes a limit for chlorite is part of which EPA rule?
• Which coliform test methods have three distinct steps: presumptive, confirmed, and completed?
• Which type of process control uses a mode where the output is directly proportional to the deviation from the set point?
• The process of removing organics from a water sample and concentrating them in a solvent suitable for injection into the ______ is called ______.
• Which process is currently used for softening brackish water?
• Which pair of colors is not assigned numerical color units?
• The concentration of a disinfectant multiplied by the contact time from application to first customer must be calculated ______.
• Disinfection byproducts increase as ______ increases, and low pH favors ______ and high pH favors ______.
• What information can particle counters provide?
• Compared to Stage 1 Disinfectants and Disinfection Byproducts Rule (DBPR), what major change was made when Stage 2 DBPR was promulgated?
• Which chemical is commonly added to provide alkalinity and facilitate precipitation of iron in water treatment?
• For manganese oxidation in surface water, which pH value would be sufficient to make the process effective?
• To ensure adequate contact time before chlorine addition, PAC should have at least ______ minutes.
• Which device best measures total suspended solids?
• Increasing which factors together will decrease corrosion rate?
• Which regulatory rule explicitly includes monitoring for TTHM and HAA5 by Stage 1 DBPR?
• Which instrument has a fixed light source and provides a qualitative measurement but cannot detect particles that do not scatter light?
• There are two types of acidity: phenolphthalein acidity, which is prevalent ___________, and mineral acid acidity, which tends to be in the ________.
• What are hearing protection devices given to evaluate their effectiveness?
• Which of the following defines carbonate alkalinity?
• Which type of process control can be used if accuracy is not critical?
• What is the approximate open-circuit voltage per cell in a lead-acid battery?
• Which structural feature do buttress dams rely on to transfer the water load?
• What unit is used to report arsenic concentration in drinking water standards?
• What is the one objective of a safety program?
• Electrolytic flotation uses which gas mixture as a byproduct?
• Which radon removal method is most effective considering cost and footprint?
• In variable declining-rate filtration, what is placed in the effluent line of each filter to prevent excessive flow rates?
• Which are usually the only cations present in water in significant concentration?
• What acid is more corrosive when it is diluted?
• What will most likely exhaust GAC first?
• What is the main consideration in determining the length of the service stage of an ion exchange softener?
• What factor explains why the bulk density shipping weight differs from laboratory density?
• Under the Surface Water Treatment Rule, the turbidity entering the distribution system must not exceed _____.
• Where is nitric acid most commonly used within a water treatment facility?
• The low-cost radioactive scan threshold for further analysis is normally the ______ for ______ or ______ but can be varied by the state agency.
• In a concentration cell corrosion, what gas is produced?
• The Long Term 2 Enhanced Surface Water Treatment Rule specifies that UV disinfection must provide at least what level of log removal for Cryptosporidium?
• Which regulation includes Giardia reduction credits for conventional treatment with disinfection?
• Which agencies are recommended to set the optimum fluoride level in drinking water?
• Microfiltration is considered to be intermediate between _______ based on pore size
• What filter types would be best for direct filtration?
• Iron bacteria, such as which organism, cause red water, tastes and odors, clogged pipes, and pump failure?
• Which of the following is not a part of a bearing?
• Absolute ratings for membranes are based on which pore-size measure?
• ______ and ______ should not be stored in the same refrigerator.
• The flocculation and settling of calcium carbonate and magnesium hydroxide precipitates occur more quickly in the presence of what?
• What is skeletal fluorosis?
• An organic compound from components of pipe, coatings, and joint adhesives would most likely include...
• What is the CT value?
• Which chemical is primarily responsible for precipitating magnesium hydroxide during lime-softening?
• A water that does not form scale or corrosive is stable; this condition is called what?
• A hazardous measuring device would most likely be _______
• Threshold odor tests on the raw water and finished water while PAC is being fed should be performed at least
• When disinfecting with chloramines, when can the ammonia be added to the process?
• The current travels end-to-end at high speeds; electrons move relatively slow over short distances. Which option correctly reflects this statement?
• In the oxidation of iron and manganese, the pH must be adjusted to an optimal level. What must be determined to accomplish the optimal pH?
• Which temperature-time combination is used to heat a shaft sleeve prior to installation?
• Which parameter most strongly influences permanganate reactions in water treatment?
• In calculating the C x T value, the contact time is extended to which point in the system?
• Which option shows the correct pairing for caustic soda?
• Continuous regeneration (CR) is usually used in greensand filters when ________ is mostly being removed and intermittent regeneration (IR) when __________ is mainly being removed. The _________ regeneration is used while the filter is offline.
• The Surface Water Treatment Rule requires that the turbidity of the water entering the distribution system be equal to or less than ______ in at least ____ of measurements each month.
• What is alkalinity?
• In manganese greensand filters, the greensand is usually capped with at least _____
• A condenser will allow which type of current to flow through it, but block the other? One use is to suppress voltage surges.
• The specific ultraviolet absorbance (SUVA) is calculated using the absorbance of UV light at 254 nm ______ the concentration of _______
• Chelation is a chemical treatment process used in water treatment to control which condition?
• Which statement about carbonate hardness is correct?
• To provide adequate protection, what should the noise reduction rating (NRR) of the hearing protection device be?
• When using calcium hypochlorite, calcium carbonate scaling can occur on the suction and discharge sides of the pump. What is the best solution?
• Greensand filters are often capped to enhance filter performance and backwash efficiency. It is common to cap them with...
• The sediment from presedimentation systems can be kept if samples are collected _________.
• What is the new MCL for uranium established by the final Radionuclides Rule?
• Which unit is commonly used to express viscosity in the Saybolt Universal system?
• When natural gas and air are used to make CO2 for recarbonation, good ventilation is required because dangerous concentrations of which gas are produced?
• Which pairing of membrane processes is effective for removing hardness from water?
• In 2003, the USEPA revised the drinking water standard for arsenic from which range to which range?
• To preserve sediments from presedimentation for analysis, which sampling method is recommended?
• When using chlorine disinfectants, lower temperatures favor the formation of _______. Lower temperatures also show _______ to persist somewhat longer.
• Caustic soda is also known as
• When chlorine dioxide is generated on site, a small amount of which species can be formed?
• Why do some water treatment plants avoid addressing iron, manganese, arsenic, and disinfection byproducts in their treatment operations?
• What treatment chemical is corrosive, dense, and an oily liquid and is available in strengths of 62%, 78%, and 93%?
• What is the typical detention time for the recarbonation process?
• Airline supplied air is not commonly used for emergency response because they are limited to only _______ ft.
• Lime slakers should be equipped with a _______ that will stop the lime feed before _______.
• The oxidation of manganese in surface water is not effective until the pH goes to or surpasses which value?
• Which combination describes a low-cost PAC feed method suitable for secondary treatment?
• Which chemical is used to raise alkalinity in water treatment?
• If PAC does not remove tastes and odors, what is a likely explanation?
• What type of pretreatment must be cleaned manually when the amount of debris is relatively small?
• In a filtration system, adding an anthracite coal layer over greensand primarily improves which performance aspect?
• Groundwater systems at high risk for fecal contamination must provide a 4.0-log inactivation of viruses.
• Under the Ground Water Rule, large systems disinfecting must monitor continuously while small systems must monitor daily.
• What is the function of bases in a treatment plant?
• What is the correct order of parts that follows a pump for the listed components?
• In a buttress dam, the impounded water's weight is used to resist which forces?
• What happens when high chlorine residual levels are applied to the softening units?
• What does total hardness represent?
• Turbidity is typically measured in what units?
• What is the primary advantage of placing a properly sized anthracite coal layer over manganese greensand?
• All sedimentation basins should be equipped with which of the following safety features?
• In reporting the water quality, turbidity is expressed in which unit?
• The reason that a sample has a holding time is usually because the sample's ____ .
• What material is commonly used to cap greensand filters to improve performance?
• Chelation controls _______, and sequestration controls _______.
• Noncarbonate hardness is defined as
• How often must an ozone-using system monitor bromate at the distribution system entry point?
• What type of pump has the ability to rotate its discharge 360 degrees?
• What is under the state-level aquifer protection standard setting?
• In groundwater systems that disinfect and have deficiencies, 4-log inactivation of viruses must be demonstrated with adequate C x T.
• Driven wells are practical only when the water-bearing formations are relatively close to the surface and no contaminants exist in the soil. Which option best reflects this condition?
• Which errors often cause inaccurate iron and manganese test results?
• Without pretreatment, which membrane processes must be used to remove dissolved organic matter?
• Electric energy is usually expressed in _______, and power is expressed in ______
• Reverse osmosis units also have cartridge filters installed immediately ahead of the RO unit to remove suspended matter down to _____.
• No preliminary contact or sedimentation chambers are necessary for which oxidation process?
• Hardness is generally expressed as the total concentration of which ions?
• Which compound is commonly used to prevent encrustation by sequestering metal ions?
• Before reinstalling a shaft sleeve or impeller, which cleaners should be used?
• Interferences to aerometric chlorine residual measurement come from nitrite.
• What instrument is used to measure the depth to gravel in a filter bed?
• When is the best time to start using a destratification equipment to overturn a lake?
• What membrane process will remove hardness?
• Nitrite interferes with which chlorine residual measurement method?
• What is a common disadvantage of using caustic soda to soften hard water?
• The LT2 Enhanced Surface Water Treatment Rule added tests that were not in the original rule. Which tests were added?
• Why is ozone treatment often followed by granular activated carbon, which removes assimilated organic carbon caused by the action of the ozone treatment?
• What corrosion prevention chemical may actually cause tuberculation in iron pipe in the pH range of 7.5-9.0?
• In the wellhead protection program, which technical step is essential?
• Phenolphthalein acidity is prevalent above which pH value?
• What should the operator do for best results in a plant with six flocculators?
• Chlorite monitoring is required only for systems using ______
• One key element of LT2 is to use monitoring results to classify surface water sources into USEPA-defined risk levels called bins. How many bins are defined?
• What will a coagulant aid not achieve from the following?
• Which health indicator may suggest a child has been exposed to high lead levels?
• Which option lists the correct formula for caustic soda?
• In the Ground Water Rule for systems that disinfect, large systems are required to monitor ______ and small systems are required to monitor ______.
• Color in the ______ range is determined by a visual comparison of the sample with either a known colored chemical solution or a calibrated color disk.
• While converting carbonate back to bicarbonate, how does recarbonation affect the pH?
• Which option is NOT a purpose of polyphosphate addition in softening water?
• Where is arsenic found naturally?
• Jar tests are used to determine the powdered activated carbon dose. The glassware used need to be cleaned with _____ and rinsed with _____ water.
• Which chemical is used to regenerate manganese greensand beds?
• To prevent algae growth, which action is most appropriate?
• If raw water is pre-chlorinated, what color on the inside walls of filters and the filter media indicates the presence of both iron and manganese?
• What does the optimal pH establish when applying oxidation to iron and manganese?
• What happens when the brine solution is fed into the resin?
• Before installing casing wear rings, what preparation step is recommended?
• Microfiltration sits between ultrafiltration and multimedia filtration based on pore size. Which option correctly lists those adjacent stages?
• If a water system exceeds the 90th percentile of either the lead or copper action levels, it must also assess _______.
• What is caustic alkalinity?
• If any stains or chemical residues remain after normal cleaning of labware, the glassware should be washed with a cleaning solution such as acid-dichromate.
• What genus type or organism has killed the most people because of its high mortality rate when contracted?
• In order to achieve similar disinfection, combined chlorine residual must be greater than free chlorine by how many times under favorable conditions?
• If a particular section of the distribution system suddenly has a drop in chlorine residual, what most likely has occurred?
• How are manganese greensand beds regenerated in typical treatment systems?
• What can greatly reduce fire hazards?
• What is the primary purpose of routing power through transformers at a water treatment facility?
• Ozone may convert large organic molecules into smaller ones. These BDOC compounds serve as food for which organisms?
• Where is the heater located that vaporizes any chlorine liquid that may develop downline from an online one-ton container?
• Diatomaceous earth filtration is used for raw water that has a maximum turbidity of ____.
• The DBPR focuses on which group of contaminants?
• Why is nitrate regulated?
• What is the result of overexposure to hypochlorite compounds?
• Chloramines will be used when tastes and odors are a problem, particularly when the source water contains
• In a presedimentation impoundment, which option would most directly limit algae growth by reducing light exposure?
• How can the problem of poorly formed floc be solved?
• In the presence-absence test, the presence of total coliforms is indicated by the medium turning yellow and the formation of what?
• A filter core sample is best collected for solids retention analysis when
• If there is no pretreatment, what membrane processes will remove dissolved organic matter?
• Which term refers to the EPA program that surveys unregulated contaminants in drinking water?
• Which parameter is used to quantify disinfection effectiveness as the product of concentration and time?
• The major provisions of the LT1ESWTR include the control of ____ and ______ turbidity performance standards.
• At pH levels associated with softening chemical precipitation, which component in the treated water may increase?
• As the TOC increases, the TOC percentage removal required from a source water supply _______.
• Slow sand filters are cleaned by scraping the top ____ off the top of the sand filter.
• When ozone is used as a primary disinfectant, which byproducts may form that require monitoring?
• Reverse osmosis membranes need cleaning if the pressure drop through the unit increases by what percent?
• What are the effects of high iron and or manganese in water?
• The ideal alkalinity for manganese greensand filters for the removal of iron and manganese is _______ as CaCO3.
• Soft water is defined as CaCO3 equivalents below what value?
• In groundwater, the total dissolved solids will change ______ and the dissolved oxygen will change _______, with the dissolved oxygen lowest most probably around ________.
• Actinomycetes are a group of organisms usually associated with tastes and odors. This group has the characteristics of _______.
• To address iron problems when using resin exchange, which pre-treatment step is recommended?
• The ____ process is used in the water industry primarily for the removal of ______.
• Alternate description of glassy phosphates: Glassy phosphates are best described as which of the following?
• The chlorine-measuring method that uses a chlorine gas-permeable membrane is the polarographic method.
• Under the Interim Enhanced Surface Water Treatment Rule, what Giardia log reduction credit is given for conventional treatment with disinfection credits?
• What should you base a safe stopping distance behind the vehicle in front of you on?
• Bar or wire-mesh screens typically encounter the largest amount of debris in which season?
• Which regulation protects public health by limiting levels of contamination in drinking water under the Safe Drinking Water Act?
• Destratification is most effective when the lake has a stable layer of warm surface water over cooler bottom water.
• Mass spectrometry identifies organic compounds by which characteristics?
• PDVF membranes have excellent chemical resistance to which substance, and what is their typical service life?
• Stage 2 DBPR includes a provision to reduce or eliminate the use of chlorine disinfectants at the beginning of the treatment process if TOC exceeds 2.0 mg/L.
• Which statement about high iron and manganese in water is true?
• Point-of-use activated carbon filters are most effective for removing _________.
• Which statement correctly describes HOCl versus hypochlorite at low pH and low temperature?
• In the Long-Term 2 Rule, the bin scenario represents source water concentrations used to assess what?
• Microfiltration membranes made from PDVF have excellent chemical resistance to which substance, and what is their typical service life?
• Because bromine is not as stable as chlorine, if it were used to treat public water supplies, how much more would be needed?
• What is titration?
• Which softening process would probably not meet the Surface Water Treatment Rule requirements?
• A gravity dam resists both ______.
• Why is polyphosphate added to softening process water?
• For conductivity measurements, which sampling option is correct?
• What are the primary reasons that more small water systems are installing pressure filters?
• What should an operator do if hardness leakage is excessive immediately following a regeneration stage?
• Chlorine dioxide is how many times more powerful than chlorine?
• Iron complexes with organic matter are anionic and are not removed by which type of exchange?
• What is used to coat the walls of sedimentation basins to rid the basin of slime growth?
• Which year range best represents a long-range planning horizon for a water system's source of supply?
• Ozone is more stable in water when the water has which condition?
• Which condition indicates poor floc formation?
• What is the purpose of using granular activated carbon after ozone treatment, as described?
• Which chemical is used as a corrosion inhibitor in water treatment?
• Which statement about pH and magnesium hydroxide precipitation is true?
• What chemical is used for oxidizing iron and manganese that needs a reaction basin?
• In viscosity testing, which unit is commonly used to express viscosity?
• Emergency response at a water treatment facility generally means responding to a _______. This response is governed under the ______ and under _______.
• What compounds are formed when calcium and magnesium are precipitated out of water in the lime softening process?
• The Information Collection Rule requires large water systems to collect information to build a database to assist in the development of which regulations?
• Which combination is used to coat sedimentation basin walls to rid the basin of slime growth?
• HPC method, and how long are samples incubated?
• The C x T value is calculated using most or part of the treatment plant, some distribution piping, and to the _______.
• Among the VOCs found in groundwater, which are encountered most frequently and in the highest concentrations?
• Which chemical family is used to regenerate ion-exchange systems and lower the pH of water treated by membrane processes?
• Which action best reduces siltation in a reservoir?
• Separate refrigerators should be used for the storage of _____ and ______ because the fumes of some chemicals may be harmful to ______.
• For conductivity sampling, which statement is correct?
• Which colors are not assigned numerical color units?
• What is the minimum free chlorine residual at the customer tap that is considered acceptable for ongoing disinfection?
• Under the Emergency Response Planning Guidelines #2, what is the maximum airborne concentration of chlorine below which nearly all individuals could be exposed for up to 1 hour without experiencing or developing irreversible or other serious health effects that could impair an individual's ability to take protective action?
• When dewatering alum sludge using mechanical equipment, pretreatment is typically done with which device and feature?
• A calcium sulfate molecule would be considered a dissolved solid.
• Large bubble diffusers can be cleaned with which method?
• The chlorine-measuring method that uses a gas-permeable membrane is the polarographic method.
• In the multiple-tube fermentation method, as presumptive positives are inoculated into Brilliant Green Broth (BGB), 0.1 mL of the presumptive broth is also transferred into which medium?
• Which two test methods for coliform bacteria include a three-step process?
• According to best practices, tip speed of the last flocculator should be about ______ and operate in the range of _______.
• Which results are used to develop the Langelier saturation index?
• Which feed system reduces handling problems with powdered activated carbon?
• Under current regulations, what type of samples must be collected from the source water supply?
• What is the mechanism by which potassium permanganate works when used to control algae?
• In determining a safe following distance, you should primarily consider
• What membrane process will remove dissolved solids?
• Adjustments to the carbon dioxide dosage in recarbonation should be based on both the Langelier saturation index and results of coupon testing.
• In the lime-soda ash softening process, smaller plants find that ______ is less expensive to purchase; regardless of size, ______ needs to be mixed long enough because it dissolves slowly.
• Under USEPA radionuclide sampling frequency for entry point testing, if results are greater than or equal to one-half the MCL and less than the MCL, sampling frequency is every how many years?
• Chlorine dioxide can revert to chlorite and chlorate under which conditions?
• How do the Surface Water Treatment Rules define surface water?
• What is the best solution for iron problems when using exchange resins?
• If too much aeration occurs after clarification and filtration, which process will most probably suffer?
• Which list identifies contaminants not regulated by current standards and monitored for potential future regulation?
• Air binding can cause which of the following effects on flow?
• A calcium sulfate molecule would be considered a dissolved solid.
• Garnet sand is used at the bottom medium in multimedia filters. What characteristics does garnet sand have compared to the other sand in the filter?
• What is CaCO3 known as?
• What is the only reliable method of detecting hydrogen sulfide in the air?
• What is an ion?
• Which chemical is used to remove noncarbonate hardness in chemical precipitation softening?
• Compared to conventional sedimentation, dissolved air flotation achieves what with cryptosporidium removal?
• In the lauryl tryptose broth test, which observation corresponds to a positive result?
• If a radionuclide is above the MCL in finished water, how often must sampling be done and for how long?
• Regarding the USEPA sampling frequency for radionuclides in drinking water for individual contaminants at each entry point: If results of testing are below the detection limit of an approval method, what is the frequency of sampling?
• What membrane configurations are currently available and used in drinking water treatment plants?
• Which organism was introduced to the United States from Southeast Asia and has become a significant pest in almost every river system?
• If a water system exceeds the action level for lead and copper, which parameter must be measured in the laboratory?
• Which membrane process combination removes hardness?
• Under the Stage 1 Disinfectants and Disinfection Byproducts Rule, which compound has an MCL of 1.0 mg/L?
• In water treatment, chelation is applied primarily to prevent which condition?
• Besides using carbon dioxide, encrustation can also be prevented by adding ______
• In the presumptive test, if gas is produced after either the 24-Hour or 48-Hour incubation period, the sample must undergo the confirmed test.
• What is the most common disinfection byproduct when chlorine is added to water containing natural and inorganic matter?
• A gravity thickener would include which of the following components?
• What is the main source of chlorite in drinking water?
• Hydraulic fracturing uses pressure to force ______ into existing fractures to open and separate different _____.
• What is the typical service life range for PDVF membranes in oxidants?
• Which statement is true about the Contaminant Candidate List (CCL)?
• The fluoride injection point should be as far away as possible from any _____.
• What is the main, easiest way to identify a confined space?
• _____ pipettes are used for performance monitoring and should be ______
• When do bar or wire-mesh screens usually encounter the largest amount of debris?
• The most used conductor metal is?
• Which regulation governs microbial monitoring in drinking water distribution systems?
• Why are primary standards or MCLs enforceable by law?
• The Long-Term 2 Enhanced Surface Water Treatment Rule also calls for continuous monitoring at the entry point to the distribution system with a minimum of ______ of chlorine residual.
• Which alum sludge dewatering method can attain at least 20% solids by weight?
• For source water at or below 10 NTU, the sedimentation effluent should meet which turbidity criterion for 95% of the time?
• Which process is used in the water industry primarily for the removal of organic substances?
• In lime-soda ash softening, which compound is formed by reaction of lime with carbonate hardness?
• What corrosion prevention chemical may be the best overall treatment approach?
• In the Stage 2 Disinfectants and Disinfection Byproducts Rule, new sampling sites are based on what evaluation?
• To demonstrate 4-log inactivation of viruses, adequate C x T must be provided.
• Which device would best measure total suspended solids?
• Scale is formed from the combination of which?
• Which statement best describes the focus of the primary drinking water regulations?
• Cartridge pre-filters installed ahead of a reverse osmosis unit serve what purpose?
• In the context of softening, floc is often composed mainly of which precipitate?
• It is recommended that the free chlorine residual at a customer's tap should be at least ________.
• Monomedium filters are best suited for which filtration approach?
• Cryptosporidium and Giardia typically range in size from which of the following?
• Which chemical looks like broken glass crystals?
• The 1996 Risk Management Rule was issued to protect public health and safety for which group?
• Backwash bed expansion to prevent media loss is designed to reach what percentage?
• Under LT2, surface water sources are classified into how many USEPA-defined risk levels called bins?
• ______ or small streams at the upper end of a reservoir can help reduce _____
• Emergency response at a water treatment facility is governed under which combination?
• What has caused a significant increase in environmental aluminum exposure?
• What is the filter bed used for in the softening process?
• Which statement about the lime-soda ash process characteristics is correct?
• Permanganate reactions are largely dependent on ________.
• Which compound looks like broken glass crystals?
• In HPC testing, where are the diluted water samples placed and how long are they incubated?
• Point-of-use activated carbon filters are most effective for removing ______.
• After water has been softened, it is close to pH 11; thus it needs to be stabilized by a process known as recarbonation. What small amount of hardness chemical is formed and what is precipitated in this process?
• Point-of-use activated carbon filters are most effective for removing which of the following?
• Air binding is caused by pressure in the filters ______ than atmospheric pressure, and it can cause ______ flow.
• Caustic hypochlorite used in disinfection ranges in available chlorine from which percentage?
• This parameter is used to determine if the Disinfectants and Disinfection Byproducts Rule is in compliance.
• Caustic soda is also known as which option?
• What indicates whether the small amount of fluid in the tip of a pipette that remains after it has drained should be blown out?
• To address algae growth in sedimentation basins, which combination is applied per liter when drains are used?
• Which type of aerators have riffle plates?
• Chlorine dioxide has gained popularity because it:
• In mass spectrometry identification, the key signature used is which?
• Which material sits on the top in the standard bottom-to-top arrangement of higher-rate filter media?
• What is an operating factor that would affect floc formations?
• What is the best-known solution for excessive algae growth in a presedimentation impoundment?
• Define cation.
• Why is electrical power entering a water treatment facility usually routed through transformers?
• Which of the following is the correct alternative name for hydrochloric acid?
• Which method is listed as another approach for the modified Winkler method?
• Which factor will cause problems for chlorination?
• What should be done to a new shaft sleeve before it is put on a shaft if it uses an o-ring?
• In SUVA calculation, which pairing is correct?
• Which protozoan parasite is a key target in modern drinking water treatment due to resistance to disinfection methods?
• Lime precipitation of noncarbonate hardness forms which noncarbonate salts?
• Which statement best describes the factors that influence cleaning protocols for microfiltration membranes?
• Methyl orange used as an indicator in titrations is ______ on the alkaline side and _______ on the acid side.
• Which pipette type is used for performance monitoring and should be Class A?
• The suction side of a pump's piping should be ______ pipe size ______ than the intake side of the pump.
• Molecular weight is expressed in which units?
• During HAA5 analysis, which chemical is used to quench further HAA5 formation?
• Before installing a new shaft sleeve, it should be heated to _______.
• The Filter Backwash Recycling Rule is intended to minimize health risks associated with recycling backwash water, particularly with respect to which pathogen?
• ________ is often added to provide _______ and facilitate iron precipitation
• Water that is highly colored with organic material requires a _______ pH for coagulation; therefore, ________ before _________ may be necessary.
• It is recommended that operators using particle counters track particles in the size range ______ because they are a possible surrogate for _______.
• Phenolphthalein is colorless at low pH and pink or red at higher pH. How does it appear at pH below 8.3 and above 8.3?
• Which factors contribute to the difficulty of inactivating all microorganisms with a single treatment method?
• Which statement best describes circuit breakers in relation to switches?
• In lime-soda ash softening, what are used to help gather the fine calcium and magnesium precipitates into particles that will readily settle?
• What best describes an operator taking an active role in safety?
• Cyanide affects which body systems?
• Lamella plates create flow by
• Lime softening effect on disinfection
• Which agency defines the risk bins used to classify surface water sources under LT2?
• Chlorine dioxide can revert to chlorite and chlorate under which conditions?
• What type of automation control would work best if the chlorine demand varies but the flow is constant?
• What is produced after colloids have just become charge neutralized?
• If a UV reactor is operating outside of the validation limits by more than _____ of the water treated, it is considered off-specification.
• A Leopold filter bottom is a patented filter underdrain system using a series of perforated _______ with channels to carry the water.
• What is the maximum contaminant level (MCL) for arsenic in drinking water?
• In open filters, which pairing of media is associated with superior organics removal?
• Which treatment chemical raises pH?
• What is the most common radionuclide anion?
• Which term describes a water's buffering capacity?
• In dual-media filtration, if the ratio of anthracite size to sand size is close to 2, what is a likely outcome?
• The dosage of lime and soda ash at a softening plant is based on which of the following alkalinities?
• Which problem is commonly associated with hardness?
• In water treatment, which compound is described as looking like broken glass crystals?
• If a routine or repeat sample tests positive for total coliforms, it must also be analyzed for _______.
• Which statement about the lime-soda ash process is true?
• Which of the following salts is not typically a hardness-causing salt?
• The optimum fluoride level in drinking water, as recommended by the Department of Health and Human Services and the USEPA, is what?
• Which agency promulgated the Final Groundwater Rule?
• In the lauryl tryptose broth test, which combination describes the bacteria associated with a positive result?
• What indicates that water produced by a well is being drawn from more than one aquifer?
• The solubility of calcium carbonate decreases as temperature increases.
• What is the MCL for radon in drinking water?
• Chelation is a chemical treatment process used in water treatment to control what?
• Manganese is naturally found in soils primarily as _______ and in the two forms of _______.
• Which method is the least reliable for detecting hydrogen sulfide?
• Which is a limitation of softening?
• The rate of formation of _____ increases with increasing pH
• Some systems using aeration towers are required to install air scrubbers. These scrubbers use _____.
• Which type of sample is specifically excluded from mailing to a laboratory for transport?
• How many grains are in 1 pound?
• Which statement best describes the focus of the discussed rules in relation to drinking water?
• In a corroding pipe, the electrons released at the anode will combine with which species in the pipe at the cathode?
• In an electrolyte solution, an anion is attracted to which electrode?
• Why are drinking water regulations sometimes called interim regulations?
• How does cyanide affect the human body?
• Under LT2, which three parameters were added for testing?
• What pH is needed to form the magnesium hydroxide precipitate?
• What process is currently used for softening brackish water?
• Separate refrigerators should be used for the storage of which items because fumes of some chemicals may be harmful to the organisms?
• Chlorinating before a microstrainer may cause a sticky, jelly-like coating to form on the microstrainer. What is present in the water that causes this problem?
• Which oven is used to burn solids?
• Jar tests are used to determine the dose of which material in water treatment?
• The LT2 rule requires a minimum chlorine residual at the entry to the distribution system. Which value is specified?
• Which filter has an unstratified media distribution?
• Define anion.
• Excessive up-thrust on line shaft turbines is caused by
• What is the required minimum alkalinity (as CaCO3) for manganese greensand filters?
• Which statement about pumps is false?
• Ammonia is a dangerous gas and is readily detectable at concentrations of ______.
• Slow sand filtration cleaning involves removing how many inches from the top of the filter?
• Superchlorination is typically used when ______ are excessive
• Beneath the slime layer of certain iron bacteria in a pipe, what is produced that reduces pH and speeds up the corrosion rate?
• What is the most common unit of hardness?
• For nomographic determination of CO2 in water, which additional properties must be known?
• Under LT2, UV disinfection is specified to provide at least a log removal/inactivation for which organism?
• Sodium hypochlorite is usually purchased at 12% to 12.5% and is then distributed down to a more stable percentage of ______.
• Synthetic organic compounds are more likely to contain which halogen than natural organic compounds?
• Which chemical lowers pH when added to water?
• What is another name for hydrochloric acid?
• Which gas(es) does electrolytic flotation use?
• Carbonate hardness relative to total hardness
• A metal rod should be used to probe the filter on a grid system to locate and record the depth to gravel. At a minimum, how often should this be done?
• During manganese greensand bed regeneration, which chemical is used to regenerate the media?
• When iron corrodes, it converts from which form?
• Under the ______, nonuse for a long period of time may result in loss of water right by forfeiture or abandonment.
• In the completed test of the multiple-tube fermentation method, a small portion of a coliform colony from the confirmed test that is positive is transferred to a growth medium and inoculated for _______, and a second portion is transferred to _______ and incubated for _______.
• In coagulation, once zeta potential forces are reduced below the ______________, the particles in suspension will start to coalesce?
• Using dry ice or liquid CO2 as a diffuser gas results in smaller diffuser pipes.
• Hypochlorous acid is favored over hypochlorite ion when the pH is _____ and the temperature is ________.
• In open filters, which media arrangement provides superior removal of organics?
• Besides oxidizing iron and manganese, potassium permanganate has been found to be most effective in controlling...
• In microfiltration operation, stable flux is maintained while recovery is kept at or above what percentage?
• Which oxidant used for iron and manganese will react with hydrogen sulfide and will not form trihalomethanes?
• The analysis of a water sample yielded a result of 4.0 mg/L CO2. What is the most likely source of this water sample?
• Which solvent is used to clean an old bearing?
• Which skin condition has lower resistance to electrical current flow?
• In a lead-acid battery, each of the battery cells produces an open circuit voltage of approximately ______
• What is the percentage of copper in copper sulfate (CuSO4)?
• The final RCTR requires which entity to notify the public if a test exceeds the MCL for E. coli in drinking water?
• TOC removal requirements increase as alkalinity decreases. Which of the following best describes this relationship?
• Fluoride injection should be kept away from which type of chemical?
• What do the routine monitoring requirements of the Stage 1 DBPR include?
• Which two hardness-forming cations are most commonly present in significant concentrations?
• Titration is best described as a method used to determine the composition of a sample by incrementally adding a standard solution until what occurs?
• The ripening of a filter after it backwashes depends on ________.
• Which statement is true about the Saybolt Universal Seconds (SUS) unit?
• Bicarbonate alkalinity is caused by which species?
• A low-cost method of feeding PAC is to use a _____ where precise feed in ____
• Which component of the softening system is primarily responsible for removing suspended solids before the main treatment?
• Which skin condition provides more resistance to electrical current flow?
• Because the gas generated from _______ is pure CO2, the pipes from the diffusers can be _________ than those needed for CO2 generated on site by combustion.
• In lime softening, the precipitated solids are which of the following?
• Mechanical mixers should never be used in conjunction with which component?
• What type of aerators have riffle plates?
• Excessive algae growth in a presedimentation impoundment is best controlled by:
• At a softening plant, the most severe carryover of sludge in a sedimentation basin occurs when which condition?
• The optimum pH for the removal of excess fluoride by activated alumina is _____.
• What is the chemical formula for hydrated ferric sulfate?
• When ozone reacts with organic contaminants to form organic acids, what may this eventually contribute to the distribution system?
• One benefit of softening water
• Even after equipment is locked out and tagged, why might it still be unsafe to repair?
• Which chemical is used to raise alkalinity but requires the most maintenance?
• If a water system exceeds the action level for lead and copper, it must measure other contaminants as well. What parameter must be measured in the field?
• The precipitative softening process uses _____ that render _______ calcium and magnesium ______
• Diatomaceous earth filtration maximum turbidity value?
• What is an ion?
• What is molecular weight?
• What is the primary purpose of pressure aerators in water treatment?
• Where in the treatment plant is nitric acid most commonly used?
• Under the Stage 1 Disinfectants and Disinfection Byproduct Rule, the maximum contaminant level for haloacetic acids is 60 micrograms/L.
• Long-range planning for a water system's source of supply should be approximately which range?
• After screening and presedimentation, there should be a significant reduction in which parameter?
• The best packing for medium pressures and temperatures is ______
• The excess lime-softening process is used so that which compound will precipitate out of the water?
• An advantage of using ozone treatment is....
• A coagulant aid primary benefit is to reduce the amount of coagulant used.
• Which organization established regulations for new chemical contaminant testing?
• In greensand filtration, CR is usually used when which contaminant is mostly removed?
• Garnet sand is used at the bottom medium in multimedia filters because it is finer and greater density compared to the other sand in the filter. Which option best describes this characteristic?
• If hardness leakage is excessive after regeneration, which action is most appropriate?
• The rationale for dividing public water systems into three groups is the ______ of persons using the water.
• Which phrase best describes the crystals that resemble broken glass in certain compounds?
• Which statement correctly pairs acidity types with pH ranges?
• In water chemistry, what aspect of pH is of interest to chemists?
• Which statement about pump lubrication is false?
• In the described extraction method, the analytes are concentrated for injection into which instrument?
• What is a limitation of the ion exchange softening process?
• Methyl orange used as an indicator in titrations is ______ on the alkaline side and _______ on the acid side.
• What does the Unregulated Contaminant Monitoring Regulation provide the EPA?
• Why can rapid sand filters handle higher filtration rates compared to slow sand filters?
• The best packing material for medium pressures and temperatures is which?
• Under Stage 1 disinfection byproduct rules, haloacetic acids are measured in which unit?
• The Lead and Copper Rule is different from the other rules in that it deals with ______ to determine compliance.
• What is the typical backwash rate for resin beds?
• Which two items are specifically targeted by LT1ESWTR turbidity performance standards?
• Caustic soda is commonly known as sodium hydroxide with formula NaOH. Which of the following options correctly pairs the name with its formula?
• If TOC removal percentages cannot be met, a utility can comply with the EPA rule by removing at least ______ of _______, as CaCO3, measured monthly and calculated quarterly as an annual running average.
• In an electrolyte solution, a cation is attracted to which electrode?
• In the lime-soda ash process, what will cause increased solubility of taste and odor causing compounds?
• If dissolved oxygen increases and the pH and alkalinity do not increase, the corrosion rate will generally:
• Which material would be best to use as caps on iron bolts so the caps become the sacrificial anodes and the iron bolts the protected cathodes?
• Cleaning protocols for microfiltration membranes vary according to the membrane tolerance to changes in which parameter and resistance to which chemical?
• In manganese greensand filtration, what is the typical layer above greensand?
• Actinomycetes are commonly linked to which water quality issue?
• Riparian rights are a common-law doctrine, which body of law are they part of?
• In the Long-Term 2 Rule, which pairing correctly matches 'pack' to the concentration concept?
• Alum sludge dewatered in a lagoon for a year may still contain more than ______ of the original water.
• Which color range is used for color assessment by visual comparison with a color disk?
• Which particle size range is recommended for tracking by particle counters as a surrogate for Cryptosporidium?
• In dual media filtration, if the ratio of anthracite size to sand size is close to 2, which outcomes may occur?
• In the Lead and Copper Rule, if a water system exceeds the 90th percentile for the lead action level, the system must also _______.
• In the lime-soda ash softening process, coagulants are used to gather which substances into particles that settle readily?
• Methane dissolved in water will cause which taste?
• Which of the following correctly reflects the health concern associated with turbidity as described in the material?
• What are some uses of synthetic organic chemicals (SOCs)?
• Small and medium sized utilities are deemed to have optimal corrosion control if they meet lead and copper levels for how many consecutive sampling periods?
• If THMs are still a problem after softening, and changing the disinfectant is not an option, what other treatment process can be used and what is its disadvantage?
• Waterborne disease outbreaks have historically been traced to inadequate disinfection of drinking water. Which disease among the following has been linked to this issue?
• In nanofiltration and reverse osmosis, membrane compaction rates increase when membranes are operated at which conditions?
• When temperature increases, the corrosion rate usually ________, and when the water is corrosive and the velocity increases, the corrosion rate ______?
• A bacterial slime layer prevents the deposition of ______, and when the slime occasionally gets sloughed away, the slime carries away ______ and leaves the pipe surface bare.
• Ammonia is fed at about what percent of the amount of chlorine used?
• What is the best way to deal with accidents or safety incidents?
• How is magnesium noncarbonate hardness removed?
• Rapid pressure changes in a distribution system can cause red water due to precipitation of which iron species?
• The primary purpose of covering an algae-prone impoundment is to
• To eliminate hydrogen sulfide (H2S), the pH of the water should be lowered to _______ or less before beginning aeration.
• Which statement best describes manganese dioxide (MnO2) in soils?
• Which pump configuration allows the discharge to be oriented in any direction around the axis?
• During lime softening, the hardness-causing ions are transformed into which form as pH rises?
• Which material is commonly used as a sacrificial anode to protect iron components from corrosion?
• Engineers usually design the height of a filter's backwash collection trough to allow for _____ bed expansion without loss of media into the troughs
• Which concept defines that the proportion by weight of elements in a compound is constant regardless of the method used to form the compound?
• An organic compound from components of pipe coatings and joint adhesives would most likely include which class of compounds?
• In the EC-MUG test, if the tube _______, it is positive for E. Coli.
• Greensand filters are often capped to enhance filter performance and backwash efficiency. It is common to cap them with...
• If algae or slime growth in sedimentation basins are a problem, drain the basin and apply a solution of ______ per liter of water using a brush to remove the growth.
• Which water treatment chemicals lower the pH when added to water?