Texas Wastewater D Practice Test

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• In the SV-30 test, sludge level and condition should be assessed at least every how many minutes?
• All flow meters require ongoing preventative maintenance and periodic __.
• Circular clarifiers require a 'skirt' or ___ ___ around the influent discharge point, to minimize hydraulic short-circuiting.
• We care about wastewater composition because it relates to which of the following?
• Wastewater is about what percentage of water?
• Besides BOD, other tests that assess the organic content of wastewater are the ___ and __ tests.
• Water moves from the surface through the ground and into what by the process of percolation?
• Settleable solids removal relies on gravity during which state of the sewage?
• WAS stands for which term in the activated sludge process?
• A typical problem with fine screens is that they may accumulate __ __, causing the screen to become blocked
• What is the two-part safety procedure required when working on electrical switchgear?
• The report form for a Sanitary Sewer Overflow (SSO) is TCEQ form 0501, titled which of the following?
• Approximately what percentage of the world's total water inventory is contained in the oceans?
• Open channel flow measuring methods include velocity versus area calculations, weirs, and which type of flume?
• Physical properties are described as those that can usually be detected by
• Sedimentation is gravitational separation of settleable ___ matter from wastewater.
• Which regulatory agency sets the minimum manhole cover diameter as specified in 2008?
• Primary clarifiers remove solids from raw wastewater entering the WWTP.
• Which type of gloves should be worn when handling wastewater samples to prevent contamination?
• Which test pair are commonly used to assess organic content in wastewater besides BOD?
• The year 1906 is associated with which wastewater-related development?
• When the 'worker' microbes become sick to the extent that they are made less effective, but do not suffer a rapid die-off, this is called a(n) ___ condition.
• The USEPA maintains a list of 126 chemicals and toxic metals that may cause interferences or pass through in a POTW: this list is called the priority pollutants list (PPL). How many chemicals are on this list?
• Which best describes the recommended compaction approach for backfill material?
• What is the approximate molecular weight of water in grams per mole?
• Which condition would be required to achieve theoretical detention time in a clarifier?
• Which option best completes the phrase: a sewer use ordinance places restrictions on waste discharges to the collection system?
• Pretreatment is defined as the treatment of wastewater by a commercial or industrial user, or by the utility, ahead of the treatment plant.
• Technically Based Local Limits (TBLL) are developed by which entity?
• Water moves upward through xylem in plants by which action?
• Which parameter is used to determine how much air must be supplied in the aeration process?
• Gas formation in the sludge blanket is caused by which process?
• Which of the following is an example of a non-point source?
• Grit removal early in the process serves primarily to prevent damage to equipment and to
• The conventional activated sludge process requires an aeration tank detention time of __ to __ hours, and a F/M ratio of __ to __.
• Sludge blanket depth should not be higher than bottom ___ of the clarifier sidewall depth.
• PVC force mains shall be rated at a minimum operating pressure of how many psi?
• TCEQ may assess fines of up to how much per day per violation?
• Asphyxiation can occur at any oxygen level below what percent?
• The Imhoff tank is a(n) ___ wastewater treatment system that provides both primary sedimentation and anaerobic digestion of the accumulated raw sludge.
• when working on electrical switchgear, it must be __ __ and __ __
• Denitrifying bacteria are a class of what type of bacteria?
• For a high school diploma holder seeking Class B operator or Class III collection license, including credit for extra training, what is the minimum experience and total training hours required?
• Sand and grit contribute to sewer stoppages and cause what on pumps and other plant equipment?
• The duties of the TCEQ include which of the following?
• In differential pressure meters, what happens to pressure as velocity increases in a closed conduit?
• The phrase 'closed conduit' flow refers to flows in pipes under pressure. Which term best describes this concept?
• The amount of bacteria required depends on the amount of which entering the process?
• Can a POTW operator hold a license before accruing work experience, and if so, which license?
• Which gas produced in some wastewater environments is known for a strong odor and toxicity?
• Facultative bacteria that may proliferate in anoxic clarifier sludge conditions and may cause nitrogen bubbles are called which type of bacteria?
• In wastewater treatment, some microbes are beneficial, some make no difference, and a few may be pathogens.
• Which federal agency has authority over environmental matters, including regulation of wastewater systems?
• In the activated sludge process, which components must be maintained in optimum balance?
• Bacteria are the most ____ and the most ____ microbes in water treatment processes.
• Domestic waste is wastewater that comes from which sources?
• A good sampling point will be at the ___ side-to-side, and at the proper ___ of the flow stream.
• Minimum manhole cover diameter per TCEQ rules (September 2008) is 30 inches.
• Which term describes the authority that develops and operates the industrial waste control ordinance?
• Which term describes the system that transports wastewater from the source to the treatment plant?
• VCT is made of clay fired to a glass-like material that is highly abrasion resistant and resistant to corrosive chemicals.
• When sewage is slowed to a velocity of __ or slower, grit will settle out and collect in the grit chamber
• Which term describes flow in pipes under pressure?
• Excavations of five feet or greater depth require trench safety systems.
• Approximately what percentage of Texas precipitation returns to the atmosphere by evapotranspiration?
• Physical properties of wastewater are those which can usually be detected by ______.
• In a 1,000 ml six-part composite sample, if a portion sample was taken when the flow was 5.3 mgd, the average daily flow was 4.8 mgd, what will be the size of this portion?
• Fresh sewage has a color and odor described as
• Which process moves infiltrated water deeper into the ground to replenish groundwater?
• In extended aeration, maintaining a very low F/M ratio keeps microbes near starvation. What term describes this metabolic state?
• What does DMR stand for in wastewater regulatory reporting?
• Which term describes rod-shaped bacteria?
• The digestion chamber volume per capita is specified as what range in cubic feet?
• What sector accounts for the majority of statewide water usage?
• The name for any matter in the water that renders it undesirable for human use is which term?
• Pure water is a poor conductor of electricity. What kind of conductor is it?
• Which unit is used to describe large volumes of water for planning in Texas?
• Excavations of ___ or greater depth shall have ladders or steps within ___ of workers in the trench.
• Nitrification is the process that converts ammonia to nitrate via a nitrite intermediate. Which option correctly describes this process?
• It is the duty of the licensed operator to keep TCEQ informed of which item?
• An operator holding a Class D license works in a POTW with 0.080 mgd capacity using an Imhoff tank and stabilization ponds. Can this operator renew the Class D license?
• Which of the following best describes the scope of TCEQ responsibilities regarding water pollution control?
• Septic sewage is typically characterized by which combination of features?
• What is the term for the delegation of regulatory authority from the EPA to state environmental agencies?
• "nitrifiers" use two steps to convert ___ to ___.
• What is the primary purpose of the SV-30 test?
• Which type of sewage tends to produce gas bubbles that cause turbulence in a clarifier?
• In the carbon cycle, animals breathe ____, and plants breathe ___.
• What is the approximate air requirement per pound of BOD removed in a conventional activated sludge aeration tank?
• One purpose of preliminary treatment is to remove materials that are not
• In 2002, the agency formerly known as TNRCC formally became what agency?
• What is the detention time range for the contact tank in the contact stabilization process?
• The complete mix version of the activated sludge process applies air and influent sewage at multiple points throughout the cross-section of the aeration tank.
• A watertight collection system prevents excessive inflow and infiltration.
• The end-product of denitrification is?
• PVC pipe is of what type?
• The periodic report that contains POTW operating parameters is called a DMR.
• CMOM was intended to help operators identify what for managing their specific collection system?
• Bulking sludge may be caused by hydraulic overload or excessive which type of bacteria?
• Which distance is the horizontally required minimum from a potable water supply line for sewer lines when possible?
• The Imhoff tank designer Dr. Karl Imhoff was from which country?
• The Cloaca Maxima is the name of the ancient sewer in which city?
• The usual detention time through the AT for the conventional activated sludge process is __ to __
• Settleable solids are removed by gravity when the sewage is brought to a ___ state.
• Odor masking does not remove odor; it instead does what?
• Nitrified activated sludge requires which type of conditions to operate effectively?
• On a Class A POTW, at least one operator on each shift must hold a minimum wastewater operator license of what class?
• Which phenomenon produces upward force as the liquid moves toward the outlet weirs?
• The F/M ratio is defined as pounds of BOD per unit of biomass, typically per pounds of MLSS. Which option correctly expresses this ratio?
• On a TPDES permit, concentrations are reported in what unit, and loadings are reported in what unit?
• The mlvss test measures the concentration of which matter in the activated sludge sample?
• Which sequence correctly completes the statement: Water is the liquid medium used to ___ wastes from their point of origin, through the ___ system and to the ___ plant?
• F.O.G. stands for what in wastewater management?
• What is the residential/commercial split of domestic sewage?
• When taking wastewater samples, wear ___ gloves, and practice good ____ by washing your hands after handling samples.
• What is the term for the mixture inside the aeration tank?
• GIS stands for
• Technically Based Local Limits (TBLL) are developed by the control authority.
• What is the purpose of making the collection system as watertight as possible?
• If preventative maintenance is effective, ___ maintenance will be greatly reduced.
• The name for any matter in the water that renders it unfit for human use is which term?
• USEPA maintains a list of 51 types of industries, and sets guidelines for their discharges. These industries are classified as ___ industrial users.
• An SIU can be identified by having a flow of ___ gallons or more, or a flow that equals or exceeds ___ % of the POTW average daily flow, or contributes an amount of organic loading that equals or exceeds ___% of the POTW's average daily organic load.
• The contact stabilization process has an F/M ratio in which range?
• The contact stabilization process should have a F/M ratio of __ to __ and a contact tank detention time of __ to ___ hrs.
• A large sewer serving two or more sewer mains is called a trunk main.
• Excess grease can cause sewer ___ and is not readily ___.
• Point source pollution is best defined as discharges that originate from which location?
• Sulfur ___ produce sulfates and sulfur ___ produce hydrogen sulfide.
• Which of the following is an example of a point source?
• The Return Activated Sludge (RAS) rate should be between what percent and what percent of the incoming sewage to the aeration tank?
• Which word describes a category of bacteria, based on the shape?
• The sludge wasting system is used to remove what type of solids from the process to keep a healthy population in the aeration tank?
• Depending upon the particular modification of the activated sludge process used, enough air must be supplied to produce a DO content of __ to __ mg/L
• What attribute does VCT possess that contributes to its durability in sewer environments?
• Which agency is responsible for wastewater regulation in Texas?
• Which term describes a readily available source of water that becomes more acceptable as population growth makes water scarce?
• Typical preliminary treatment processes include screening, grinding, grit removal, grease removal, pre-aeration and
• Grease, oils, and fats that enter a treatment plant will ultimately end up as part of the ___ ___ in an anaerobic digester.
• Grit is removed early in the treatment process because
• 'Prohibited waste' is a waste that will cause ___ in a POTW.
• To prevent the microbe population from becoming unhealthy, the process utilizes which component?
• One acre-foot is approximately how many gallons?
• The water or sewage flowing out of a process unit is referred to as
• F.O.G. should be removed before it enters the collection system, and this is best managed by a good _ _ program
• Wastewater from residences and institutional establishments such as schools, nursing homes, prisons, office buildings and hospitals is called?
• Which clarifier is used as the initial solids-removal unit when wastewater enters the WWTP?
• Which entity is primarily responsible for water pollution control in Texas?
• Statewide water usage is about 16 million acre-feet per year, with the majority used for which purpose?
• Which version of the activated sludge process will have a F/M ratio of 0.03 to 0.15 and a hydraulic detention time of 20 to 30 hours?
• The Imhoff tank was designed by Dr. Karl Imhoff in Germany in which year?
• Which plant tissue is responsible for transporting water from roots to leaves?
• At concentrations above 150 ppmv, hydrogen sulfide can interfere with which sense?
• The sludge blanket in a secondary clarifier should be kept at or below which fraction of the clarifier sidewall depth?
• The Imhoff tank digestion chamber should have a volume of ___ to __ cubic feet per capita.
• One purpose of preliminary treatment is to remove materials that are not readily biodegradable.
• the preferred compaction technique is ___ ___, and compaction should be done in small __
• The treatment of wastewater by a commercial or industrial user, or by the utility, ahead of the treatment plant is called?
• the standard water leak test for a new gravity sewer indicates a maximum allowable leakage of ___ gallons per inch diameter per mile
• What is the minimum distance, in inches, that the sludge level in the Imhoff digester should be below the slot opening?
• During denitrification, which gas is produced as a byproduct?
• In an Imhoff tank, the sludge level in the digester should be kept at least ___ inches below the slot opening.
• Weir loading is a measure of the "overflow rate" per ___ of weir, and is a parameter of clarifier design.
• Under the NPP, the title of the utility that develops and operates the industrial waste control ordinance is which type of authority?
• Two basic types of lift stations are: wet pit-dry pit and wet pit-submersible.
• Weir loading is evaluated per which unit length of the weir?
• Which of the following are functions of the TCEQ with respect to water pollution control?
• What PPE combination is recommended for cleaning clarifier surfaces?
• What operation concentrates aerobic bacteria by moving sludge from the bottom of the secondary clarifier to the aeration tank inlet?
• Which organism is commonly used as an indicator of healthy activated sludge when present?
• ______ bacteria can thrive in the complete absense of DO.
• In 2002, the agency formerly known as the TNRCC formally became which agency?
• Where possible, sewer lines shall be located a minimum of __ horizontally from, and ___ vertically above any potable water supply line
• The activated sludge process operates on the principle of which type of activity in what environment?
• What is the term for the mixture of influent sewage, microbes, and air contained in the aeration tank?
• What are the two basic lift station types described?
• What is the aeration tank detention time for the conventional activated sludge process?
• A(n) inverted siphon is used to get sewer lines from one side to the other of a creek, river, arroyo, etc.
• important lift station components that must be checked regularly are:
• In an activated sludge plant, the clarifier provides detention time for solids to compress into a sludge blanket that will have solids concentration approximately 3 to 10 times as much as in the aeration tank.
• How many types of industries does USEPA list for categorizing industrial users?
• In an anaerobic digester, the scum layer forms at which part of the tank?
• The typical duration of a POTW TPDES permit is how many years?
• Open-channel flow measuring methods include velocity-area calculation, weirs, and Parshall flumes. Which device is used to measure flow by constraining water to a fixed cross-section?
• A discharge which either inhibits or disrupts the POTW, its treatment processes, use or disposal; and is a cause of a violation of the POTW's TPDES permit, or of the prevention of sewage sludge disposal, is said to be
• POTW stands for which of the following?
• What is the stated purpose for clean water in the state?
• Which state agency has authority over environmental matters, including regulation of wastewater systems?
• On average, domestic sewage is about what proportion residential and what proportion commercial and institutional?
• The minimum ditch width to install a 36 inch pipe is
• When the original sewers were built, the sewage was discharged into which of the following?
• Odor control records help evaluate collection system maintenance efforts and assess which program?
• Flow equalization in preliminary treatment is intended to do what?
• Because grit has a high __ __, it will settling more readily than organic matter in general
• Grit removal is typically included in which stage of wastewater treatment?
• When hosing down weirs or clarifier walls, suit up in __ pants and jacket, ___ boots, hat or hood, goggles and/or ___ shield and long sleeve plastic or rubber gloves.
• The large ancient Roman sewer completed around 500 BC was called which name?
• In differential pressure meters, increased velocity in a closed conduit results in which change in pressure?
• The five main components of the activated sludge process include Aeration Tank, Secondary Clarifier, WAS, and which two components?
• Keeping wastewater moving in a sewer helps prevent septic conditions and line blockages.
• Plants release water vapor through openings called what?
• Every wastewater utility should have a ___ ___ ordinance, that places restrictions on waste discharges to the collection system.
• What is the main purpose of issuing entry-level wastewater operator licenses such as Class D?
• Screening of raw sewage is required for the __ of downstream treatment units and pumping units
• When the pH of the sewage is too high, this is usually an indicator of a ___ material released into the collection system.
• The nitrified activated sludge in a clarifier can begin forming nitrogen gas bubbles if the sludge becomes which condition?
• Sewer systems should be designed for a minimum __ year life span.
• Federal and state law require any system with a daily average flow of ___ or more to have an industrial waste ordinance (IWO) in accordance with the __ __ program.
• The basic principle of the secondary clarifier is to separate what from what?
• MLVSS stands for which of the following?
• pH is a direct measure of the ____ of the ____ ion, and an indirect measure of the ___ion activity in water or sewage.
• Which two processes does an Imhoff tank combine?
• Which statement best describes a six-part composite sample?
• Excavations of ___ or greater depth shall have trench safety systems in place.
• Lift stations, manholes and vaults represent which type of hazards?
• What is the primary purpose of monitoring or enforcement by state agencies?
• A high pH in the collection system most commonly indicates the release of
• VCT final material is described as glass-like. Which statement best describes it?
• Which two aspects are cited as the primary concerns regarding gases generated from wastewater?
• What term describes the layer of settled solids that forms in the clarifier?
• What percentage of an applicant's total experience credits must be in actual day-to-day operation or maintenance work in a domestic wastewater facility?
• Which version of the activated sludge process is a recent variation that uses batch treatment?
• The air requirement for a conventional activated sludge process aeration tank will be approximately ___ to ___ cubic feet of air for each pound of bod removed
• MLSS stands for which of the following?
• Which two state agencies may have monitoring or enforcement authority besides the TCEQ?
• Which component recycles settled solids from the secondary clarifier back to the aeration tank?
• Septic sewage is an anaerobic condition because all of the dissolved oxygen has been used up by microbes. Which term best describes this condition?
• What does the standard water leak test measure in gravity sewers?
• Which configuration distributes air across the cross-section of the aeration tank?
• When raw sewage is or may become septic, which treatment step may be necessary?
• The Priority Pollutants List (PPL) refers to which of the following?
• Presence of vorticella or daphnia in activated sludge indicates what?
• Which of the following is NOT a reason to care about wastewater composition?
• POTW stands for which term?
• What maintenance activity is typically performed on flow meters to ensure accuracy?
• If the activated sludge in your plant has no vorticella or daphnia, this indicates a ____ process.
• The SVI calculation measures the compressibility of settled activated sludge as the volume (in milliliters) of mixed liquor required to contain how many grams of settled mlss?
• Which of the following is NOT a typical preliminary treatment process?
• An inverted siphon must allow for a minimum low-flow velocity of 3 ft./sec.
• Grease traps operate on the principle that grease is ___ than water.