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Texas Class C Wastewater Treatment License Exam Questions and Answers, Exams of Water and Wastewater Engineering

A comprehensive set of questions and answers related to the texas class c wastewater treatment license exam. It covers a wide range of topics, including preliminary treatment, biological treatment, sludge management, disinfection, and regulatory compliance. A valuable resource for individuals preparing for the exam, offering insights into key concepts and practical applications.

Typology: Exams

2024/2025

Available from 12/08/2024

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Download Texas Class C Wastewater Treatment License Exam Questions and Answers and more Exams Water and Wastewater Engineering in PDF only on Docsity!

TEXAS CLASS C WASTEWATER

TREATMENT LICENSE EXAM

QUESTIONS WITH VERIFIED

ANSWERS.

  1. What activated sludge process parameters can an operator change directly? -- Answer โœ”โœ” aeration rates, waste rates, and return sludge rates
  2. What happens when the return sludge rate is too low? -- Answer โœ”โœ” there will be insufficient organisms to treat the waste load entering the aeration basin and the sludge blanket in the secondary clarifier could become too high
  3. Physical causes of sludge bulking are... -- Answer โœ”โœ” excessive hydraulic loading, settled sludge that is not promptly removed from the clarifier, inadequate weir lengths and improper ratio of depth to surface area of the final clarifier
  4. Preliminary Treatment -- Answer โœ”โœ” the 1st stage of sewage treatment where large debris, such as sticks, grit, and rags pas through a screen followed by a grit chamber, where the flow of water is slowed enough to allow for sedimentation.
  5. What are major surface waters classified as for the purposes of water quality management and designation of site-specific standards? -- Answer โœ”โœ” segments
  6. Inflow -- Answer โœ”โœ” direct discharges of storm water or surface water into a wastewater collection system (storm drains, roof

gutters, yard drains, basement sump pumps and broken manholes and wastewater lines).

  1. How many gallons per day will each person contribute to the wastewater treatment plant? -- Answer โœ”โœ” 100
  2. How much BOD will each person contribute to the wastewater treatment plant each day? -- Answer โœ”โœ” 0.
  3. Cause of septic wastewater -- Answer โœ”โœ” bacterial action
  4. Classifications of solids in wastewater -- Answer โœ”โœ” fixed/ash, suspended/dissolved, organic/inorganic
  5. Organic compounds in wastewater include -- Answer โœ”โœ” carbon, hydrogen and oxygen (animal and vegetable in nature)
  6. Type of organic matter present in wastewater -- Answer โœ”โœ” proteins
  7. BOD is a measure of what? -- Answer โœ”โœ” oxygen used up
  8. Ways that oxygen can be depleted in streams -- Answer โœ”โœ” untreated waste discharges, algae masses at night, and high BOD in the effluent
  9. A gas found in treatment systems that is NOT dangerous -- Answer โœ”โœ” dissolved oxygen
  10. Cycles of decay include -- Answer โœ”โœ” carbon, nitrogen and sulfur
  11. A flow totalizer is required when the plant design flow is more than -- Answer โœ”โœ” 0.5 MGD
  12. Non-hazardous wastes include -- Answer โœ”โœ” chlorides, alkalinity, color, phosphorous and iron
  1. Hazardous wastes include -- Answer โœ”โœ” cyanide, sulfides, organics and gasoline
  2. Synergistic Effect -- Answer โœ”โœ” reaction between waste streams
  3. How many cubic feet of screenings per million gallons of wastewater will coarse screens remove? -- Answer โœ”โœ” 0.5 to 6.
  4. Pre aeration benefits -- Answer โœ”โœ” freshen wastewater, scour gases and remove grease
  5. Main purpose of sedimentation tank -- Answer โœ”โœ” allow scum to rise and solids to settle under quiescent (low velocity) conditions
  6. What stage of treatment is grit removal usually accomplished in? -- Answer โœ”โœ” preliminary treatment
  7. Rotating Biological Contactor -- Answer โœ”โœ” a type of biological secondary treatment process
  8. Digester trouble signs include... -- Answer โœ”โœ” an increase in CO content and a decrease in volatile solids reduction
  9. Since the majority of _______ digesters are open tanks, digester liquid temperatures are dependent on weather conditions and can fluctuate extensively. -- Answer โœ”โœ” aerobic
  10. A minimum value of _________ of oxygen should be maintained in the aerobic digester at all times. -- Answer โœ”โœ” 1.0 mg/L
  11. The following processes are used to dewater sewage sludge: -- Answer โœ”โœ” vacuum filters, filter presses and centrifuges
  12. Sludge drying time is affected most by... -- Answer โœ”โœ” degree of digestion
  1. The depth of sludge drawn to a drying bed should be... -- Answer โœ”โœ” about 9 inches
  2. The moisture content of sludge transported to a municipal landfill should be less than __________. -- Answer โœ”โœ” 80%
  3. The most expensive method for the final disposal of sludge is... -- Answer โœ”โœ” incineration
  4. Disinfection may also be accomplished by... -- Answer โœ”โœ” ozone, bromine and ultraviolet radiation
  5. Forms of chlorine used in wastewater treatment include... -- Answer โœ”โœ” gas, granular and solution
  6. Chlorine is available as.... -- Answer โœ”โœ” pure chlorine in a cylinder; sodium hypochlorite solutions from 5% to 15% chlorine; calcium hypochlorite of about 65% effective chlorine
  7. When gas chlorine is added to water, the following is formed... -- Answer โœ”โœ” HOCl (hypochlorous acid) and HCl (hydrochloric acid)
  8. At 20'C the HOCl (hypochlorous acid) concentration will vary with the pH as follows: -- Answer โœ”โœ” pH 7 - 80% HOCl
  9. Chlorine combines with ammonia in wastewater to form.... -- Answer โœ”โœ” Chloramines
  10. If a chlorine dosage of 12 mg/L is added to a wastewater effluent containing ammonia and the chlorine demand is 11.5 mg/L, the residual would be ________. -- Answer โœ”โœ” a monochloramine - 0. mg/L
  11. How are protozoa (cause of amoebic dysentery) destroyed? -- Answer โœ”โœ” disinfection
  1. Other than stream discharge, what are other ways to dispose of effluent wastewater? -- Answer โœ”โœ” aquifer recharge, evaporation in a pond, and application to farm land by irrigation
  2. Clean Water Act -- Answer โœ”โœ” gives the basic structure for regulating discharges of pollutants into the waters of the United States
  3. Texas Water Code -- Answer โœ”โœ” gives the TCEQ jurisdiction over discharges of waste into or adjacent to water in the state
  4. Who reviews plans and specifications for new construction projects before construction begins? -- Answer โœ”โœ” TCEQ
  5. Water quality fees may be as high as ____________ per permit? -- Answer โœ”โœ” $115,
  6. Administrative penalties, up to __________ per day for each violation, may be assessed against any violator. -- Answer โœ”โœ” $25,
  7. Every city with more than ________ in population needs to establish a water pollution control program and hire qualified personnel to administer it. -- Answer โœ”โœ” 10,
  8. State law requires that reports are to be submitted no later than the ________th day of the following month. -- Answer โœ”โœ” 20
  9. How much settleable solids is removed in primary settling? -- Answer โœ”โœ” 90-95%
  10. How much suspended solids is removed in primary settling? -- Answer โœ”โœ” 50-70%
  11. How much BOD is removed in primary settling? -- Answer โœ”โœ” 35%
  1. How much total organic matter is removed in primary settling? -- Answer โœ”โœ” 20-30%
  2. What percentage of suspended solids will settle out within 2 hours? -- Answer โœ”โœ” 70%
  3. Required minutes of detention time for peak flow? -- Answer โœ”โœ” 54
  4. Required minutes of detention time for design flow? -- Answer โœ”โœ” 108
  5. Benefits of removing grit -- Answer โœ”โœ” wear on pump impellers, line stoppages and taking up space
  6. Too high a velocity in a grit chamber can result in what? -- Answer โœ”โœ” excess grit in primary clarifier
  7. One of the benefits of pre-aeration is -- Answer โœ”โœ” gas and grease removal
  8. Why does grit need to be washed? -- Answer โœ”โœ” because organic matter clings to it
  9. What is a flow equalization used for? -- Answer โœ”โœ” to reduce excessive flows or organic loads
  10. How can grease be removed before sedimentation? -- Answer โœ”โœ” by chlorination, aeration and skimming
  11. A primary clarifier should remove most of what? -- Answer โœ”โœ” settleable solids
  12. What conditions can influence settling of solids? -- Answer โœ”โœ” temperature, condition of solids and flow velocity
  1. Sludge from a primary clarifier should have a moisture content of what? -- Answer โœ”โœ” 94-96%
  2. By performing Imhoff cone tests on the clarifier inlet and outlet, the operator can determine what? -- Answer โœ”โœ” the efficiency of the clarifier and a sludge pumping schedule
  3. When temperature increases, water becomes... -- Answer โœ”โœ” less dense
  4. What problem is short-circuiting in a clarifier? -- Answer โœ”โœ” flow problem
  5. How should raw sludge be pumped to a digester? -- Answer โœ”โœ” slowly when it is adequately thickened
  6. In an Imhoff tank, the upper compartment serves as the... -- Answer โœ”โœ” clarifier
  7. In an Imhoff tank, the lower compartment serves as the... -- Answer โœ”โœ” digester
  8. Wastewater is treated by what organisms? -- Answer โœ”โœ” bacteria, fungi, algae, plants, animals and protozoa
  9. How many basic cell structures are there? -- Answer โœ”โœ” 2
  10. What factors affect biological growth? -- Answer โœ”โœ” dissolved oxygen level, temperature, pH and available food
  11. What is the most important microorganism in wastewater treatment? -- Answer โœ”โœ” bacteria
  12. In what ways are bacteria classified? -- Answer โœ”โœ” shape, oxygen needs, temperature and metabolism
  1. In the removal process, what must bacteria do? -- Answer โœ”โœ” gather food, digest food, utilize food and give off by-products
  2. What limiting factors affect bacteria growth? -- Answer โœ”โœ” pH, temperature, moisture and food
  3. What must the operator control in order for microorganisms to do their job? -- Answer โœ”โœ” the environment
  4. What by-products are excreted by microorganisms? -- Answer โœ”โœ” CO2, H2O and NH3 and polysaccharides
  5. Treatment pond classifications are... -- Answer โœ”โœ” wastewater stabilization ponds, aerated lagoons, facultative lagoons, anaerobic lagoons and hyacinth ponds
  6. What will a wastewater stabilization pond effectively reduce? -- Answer โœ”โœ” BOD and bacteria
  7. Anaerobic lagoon dissolved oxygen content... -- Answer โœ”โœ” none
  8. Facultative lagoon dissolved oxygen content... -- Answer โœ”โœ” DO on top and none at bottom
  9. Wastewater stabilization pond dissolved oxygen content... -- Answer โœ”โœ” DO throughout (top, bottom and middle)
  10. Depth of wastewater stabilization pond -- Answer โœ”โœ” 3-5 ft deep
  11. Wastewater stabilization ponds are... -- Answer โœ”โœ” aerobic, dependent upon sunlight and shallower than facultative lagoons
  12. Benefit of multiple inlets and outlets in treatment ponds are... -- Answer โœ”โœ” prevention of short-circuiting and will assure an evenly distributed flow
  1. The organic loading on wastewater stabilization ponds should not exceed -- Answer โœ”โœ” 35 lb. BOD/acre/day
  2. Depth of facultative lagoons is -- Answer โœ”โœ” 5-8 ft deep
  3. Raw wastewater anaerobic ponds are usually used by... -- Answer โœ”โœ” livestock feedlots, meat packing operations and industrial wastes generators
  4. Essential needs of an efficient wastewater stabilization pond... -- Answer โœ”โœ” DO, algae and bacteria
  5. The ideal orientation of a wastewater stabilization pond would be... -- Answer โœ”โœ” parallel with prevailing winds
  6. What does short-circuiting in a pond cause? -- Answer โœ”โœ” reduction in detention time
  7. A chemical factor influencing the efficiency of wastewater stabilization ponds is... -- Answer โœ”โœ” carbon dioxide
  8. Good housekeeping around ponds includes... -- Answer โœ”โœ” keeping dike clean
  9. Control tests on pond effluents include -- Answer โœ”โœ” BOD, TSS and pH
  10. Purpose of return activated sludge -- Answer โœ”โœ” to reseed the biological reactor with treatment microorganisms
  11. Describe activated sludge... -- Answer โœ”โœ” is fluffy and difficult to settle with approximately 99% moisture content
  12. How many times should a clarifier concentrate mixed liquor solids? -- Answer โœ”โœ” at least two times
  1. Purpose of wasting solids from an activated sludge system is... -- Answer โœ”โœ” remove excess biological solids, inert solids and old/dead microorganisms
  2. Control parameters for activated sludge plants -- Answer โœ”โœ” oxygen levels, wasting rates, sludge quality, return rates and aerator solids levels
  3. The air requirements in an activated sludge process are governed by... -- Answer โœ”โœ” organic loading on the plant
  4. Sludge bulking is corrected by.... -- Answer โœ”โœ” restoring environmental balance to favor floc-forming bacteria over filamentous organisms
  5. Rising sludge and gas bubbles can be caused by... -- Answer โœ”โœ” denitrification in the final clarifier
  6. What test can give operators a visual check on sludge quality? -- Answer โœ”โœ” 30-minute settling test
  7. A conventional activated sludge process has primary clarifiers that remove about ________ percent of the organic load.. -- Answer โœ”โœ” 30-40%
  8. SVI Formula (Sludge Volume Index) -- Answer โœ”โœ” 30 min settle test/MLSS x 1000
  9. Normal range for SVI (sludge volume index) -- Answer โœ”โœ” 70-
  10. What DO levels (in aeration) are optimal to maintain health of aerobic microorganisms? -- Answer โœ”โœ” 2-4 mg/L
  11. How deep should the clarifier blanket be? -- Answer โœ”โœ” filling the bottom 1/
  1. Weir loadings should not exceed _________ gal/day/linear foot of weir at peak flow (1 MGD or less plant). -- Answer โœ”โœ” 20,
  2. Weir loadings should not exceed ___________ gal/day/linear foot of weir at peak flow (1 MGD or above plant). -- Answer โœ”โœ” 30,
  3. Is activated sludge aerobic or anaerobic? -- Answer โœ”โœ” aerobic
  4. Why do pumps continually send RAS to the aeration tank? -- Answer โœ”โœ” to reseed the biological reaction in the aeration tank and remove accumulating sludge from the clarifier
  5. How much raw influent should return pumps be able to provide? -- Answer โœ”โœ” 50-150%
  6. For an activated sludge process to work properly, an operator much insure that... -- Answer โœ”โœ” enough return activated sludge is sent to the aerator to maintain the process; solids do not accumulate in the clarifier; excess solids that develop in the process are removed frequently enough to avoid build-up
  7. During normal operations, the __________ will concentrate sludge, making it 2-4 times denser than that of the mixed liquor. -- Answer โœ”โœ” clarifier
  8. Define F/M ratio -- Answer โœ”โœ” food to microorganism ratio
  9. How is F/M ratio calculated? -- Answer โœ”โœ” by dividing the pounds of incoming BOD (food) by the pounds of MLVSS (microorganisms) in the aeration tank
  10. What conditions should an operator observe in a well-controlled activated sludge process? -- Answer โœ”โœ” surface turbulence/uniform roll pattern; foam/small amount of light-colored, crisp foam; odors/mild, earthy; color/medium-brown
  1. What conditions should an operator observe in a well-controlled clarifier? -- Answer โœ”โœ” very little surface scum; a sludge blanket covering 1/4 of the bottom; uniform weir flow (all the way around); almost no rising solids and overflow should be clear and free of floc
  2. What type solids cannot go onto a trickling filter? -- Answer โœ”โœ” large suspended solids
  3. Important factors to a well operating trickling filter... -- Answer โœ”โœ” continuous food supply, aerobic conditions and a moist zoogleal mass
  4. Basic elements of a trickling filter are... -- Answer โœ”โœ” floor and walls; distributor arms; underdrains and media
  5. What must be durable and provide enough surface for bacterial growth with a trickling filter? -- Answer โœ”โœ” filter media
  6. The zoogleal mass on a filter is composed mainly of what? -- Answer โœ”โœ” bacteria and algae
  7. The materials resulting from the stabilization of waste material as it passes through a trickling filter are... -- Answer โœ”โœ” water, nitrates and carbon dioxide
  8. What are zoogleal solids called that are washed off a trickling filter? -- Answer โœ”โœ” sloughings (which settle in the final clarifier)
  9. Units commonly used to measure the rate of hydraulic loading are... -- Answer โœ”โœ” lb/ft/day
  10. Units commonly used to measure the rate of organic loading include... -- Answer โœ”โœ” lb BOD/acre ft/day and lb BOD/1000 ft3/day
  1. Trickling filters may be classified as.... -- Answer โœ”โœ” high-rate; roughing; standard-rate
  2. The underdrain system of a standard rate trickling filter should be... -- Answer โœ”โœ” designed to flow half-full
  3. The recirculation ratio of a trickling filter has an effect on... -- Answer โœ”โœ” organic matter removal; odors; filter flies
  4. What test best indicates the efficiency of a trickling filter? -- Answer โœ”โœ” percent BOD removal
  5. Filter operational problems include... -- Answer โœ”โœ” ponding; filter flies (psychoda); odors
  6. Filter ponding may be caused by... -- Answer โœ”โœ” poor quality rock; excessive organic loading; inefficient primary clarifier
  7. Methods of controlling filter flies include... -- Answer โœ”โœ” flood the filter
  8. To control odors at a trickling filter plant, the operator can... -- Answer โœ”โœ” increase recirculation, practice good housekeeping and chlorinate the influent
  9. Clogged orifices on influent distributor arms may be corrected by... -- Answer โœ”โœ” cleaning and flushing
  10. Rotating biological contactors are usually covered to... -- Answer โœ”โœ” prevent algae growth on the media
  11. The rotating discs should be... -- Answer โœ”โœ” partially submerged in the wastewater
  12. Rotating biological contactors may be... -- Answer โœ”โœ” driven by electric motors or trapped air
  1. The biological growth on the disc of a rotating biological contactor should... -- Answer โœ”โœ” contain approximately 50,000 mg/L solids; be 0.05-0.1 inch thick after one or two weeks; and be gray to brown in color
  2. The RBC (rotating biological contactor) unit must be preceded by a... -- Answer โœ”โœ” primary clarifier or fine screen
  3. A condition(s) that adversely affect(s) the operation of a rotating biological contactor is... -- Answer โœ”โœ” toxic materials from industrial wastes; hydrogen sulfide; high or low pH
  4. A buildup of solids in the tank of the rotating biological contactor may be caused by... -- Answer โœ”โœ” poor primary clarification
  5. Advanced treatment processes strive to provide a ______________ removal level of specific compounds, suspended solids, and oxygen- demanding materials than cannot be achieved through secondary treatment alone. -- Answer โœ”โœ” higher
  6. Direct filtration of secondary effluent is often used to reduce _____ solids to low levels. -- Answer โœ”โœ” suspended
  7. The most important factor affecting filter performance is the _____ of the secondary effluent applied to the filter. -- Answer โœ”โœ” quality
  8. Proper __________ is essential to filter performance. -- Answer โœ”โœ” cleaning
  9. What is the absorbent most commonly used for water treatment? -- Answer โœ”โœ” Activated carbon
  10. The use of granular activated carbon (GAC) for ______________ removal is common. -- Answer โœ”โœ” organic
  11. What can cause problems in granular activated carbon (GAC) treatment? -- Answer โœ”โœ” biological growth
  1. What has been tried as oxidizing agents in wastewater treatment? -- Answer โœ”โœ” chlorine dioxide (ClO2) Ozone (O3) Chlorine (Cl2)
  2. Many overlook what kind of oxidizing agent as an oxidant because of its relative ineffectiveness in conventional waste treatment? -- Answer โœ”โœ” ozone
  3. Laboratory-scale studies have shown that the changes occurring in the settlement of the floc are greatly influenced by what? -- Answer โœ”โœ” biological activity
  4. What is a common coagulant used for chemical precipitation? -- Answer โœ”โœ” aluminum sulfate; sodium aluminate and ferric sulfate
  5. What occurs when solutions of two different concentrations are separated by a semipermeable membrane such as cellophane? -- Answer โœ”โœ” osmosis
  6. Biological denitrification is accomplished under what conditions by heterotrophic bacteria that use nitrate during the fermentation of organic carbon materials? -- Answer โœ”โœ” anaerobic
  7. Electrons pass from the ______ source (the electron donor) to nitrate and nitrite (the electron acceptor) to promote the conversions to nitrogen gas. -- Answer โœ”โœ” carbon
  8. As what materials are decomposed, their phosphorus content is converted to orthophosphate? -- Answer โœ”โœ” organic
  9. The materials found practical for phosphorus precipitation include the ionic forms of what? -- Answer โœ”โœ” aluminum, iron and calcium
  10. The purpose of sludge digestion is... -- Answer โœ”โœ” stabilize the organic matter
  1. Sludge types may include... -- Answer โœ”โœ” activated
  2. Sludge conditioning is the process of removing water by thickening or by adding polymers or _________________ materials to improve the loading rate -- Answer โœ”โœ” inorganic
  3. What is a factor that influences the operation of sludge thickeners? -- Answer โœ”โœ” solids surface loading, temperature of the sludge entering the unit and biological activity of the sludge
  4. The proper pH for anaerobically digested sludge will... -- Answer โœ”โœ” be from 6.8 to 7.
  5. Primary volatile acids are converted by methane bacteria to... -- Answer โœ”โœ” methane and carbon dioxide
  6. The digester temperature should not change more than ______ degree C per day. -- Answer โœ”โœ” 1
  7. Anaerobic digester mixing methods include -- Answer โœ”โœ” gas mixing and mechanical mixing
  8. A cause of poor quality supernatant liquor could be... -- Answer โœ”โœ” digester overload
  9. Scum in a digester is mostly... -- Answer โœ”โœ” undigested grease
  10. Digester gas may be used to ________ digesters. -- Answer โœ”โœ” heat
  11. Digester gas should contain about _____________ methane -- Answer โœ”โœ” 65-75%
  12. Chlorine may be used for... -- Answer โœ”โœ” bulking control, disinfection and odor control
  1. The TCEQ requires at least _____ mg/L residual after _____ minutes contact. -- Answer โœ”โœ” 1 20
  2. Chlorine may be used to... -- Answer โœ”โœ” increase BOD; kill psychoda bacteria and destroy grease
  3. Chlorine could be used as an aid in trickling filter operation to... -- Answer โœ”โœ” breakup a ponding problem
  4. Chlorine contact chamber shall have at least a _____ minute detention time at peak flow -- Answer โœ”โœ” 20
  5. Gas chlorination facilities should be equipped with.... -- Answer โœ”โœ” bottle of ammonium hydroxide
  6. Chlorine equipment shall be capable of... -- Answer โœ”โœ” applying chlorine continuously; adding highest expected dosage at any time; automatic control of feed
  7. Because UV light is not a chemical, it does not alter the ______________ of the water. -- Answer โœ”โœ” physical properties
  8. The TCEQ allows the reuse of treated wastewater for... -- Answer โœ”โœ” golf course irrigation; aquifer recharge; agricultural irrigation
  9. Reclaimed water piping must be color-coded __________. -- Answer โœ”โœ” purple
  10. Reclaimed water providers must report monthly to TCEQ the _____________ and __________ of reclaimed water delivered to a user. -- Answer โœ”โœ” volume/quality
  11. The purpose of laboratory tests is to... -- Answer โœ”โœ” determine the overall efficiency of the plant; determine the effect of the discharge on the receiving stream; determine the characteristics of the waste being treated
  1. Grab samples must be used to determine.... -- Answer โœ”โœ” chlorine residual
  2. A flow-weighted "composite" sample is a... -- Answer โœ”โœ” combination of portions of samples collected at regular intervals and combined according to flow
  3. A BOD test is... -- Answer โœ”โœ” a major parameter in quality control
  4. pH is important in the operation of... -- Answer โœ”โœ” anaerobic digesters; chlorination of wastewater; oxidation ponds
  5. Total suspended solids are... -- Answer โœ”โœ” determined by filtration
  6. Adequate chlorine residuals will... -- Answer โœ”โœ” destroy pathogenic organisms
  7. Dissolved oxygen is necessary in... -- Answer โœ”โœ” secondary treatment processes
  8. Laboratory tests on an anaerobic digester may be used to determine... -- Answer โœ”โœ” digester loading and quality of supernatant and digested sludge
  9. For anaerobic digesters, good sludge, supernatant and gas production is realized at a pH of about... -- Answer โœ”โœ” 7.
  10. The test(s) that best indicate(s) the condition of an anaerobic digester is (are)... -- Answer โœ”โœ” volatile acid concentration
  11. The following tests are important in the control of an activated sludge process... -- Answer โœ”โœ” 30 min settleability test; oxygen uptake rate; microscopic examination
  12. The SVI should range from... -- Answer โœ”โœ” 70-
  1. A low SVI may indicate... -- Answer โœ”โœ” sludge is settling too fast
  2. A low oxygen uptake rate might indicate... -- Answer โœ”โœ” toxic waters, low DO or low BOD
  3. Good activated sludge will contain... -- Answer โœ”โœ” a high percentage of stalked ciliates and large numbers of rotifers
  4. The TCEQ monthly effluent report must be submitted to the TCEQ in Austin by the ______ day of the month following the month being reported -- Answer โœ”โœ” 20th
  5. What substances should NOT be dumped into the collection system? -- Answer โœ”โœ” acids; caustics; chemical fertilizers
  6. All anaerobic digester roofs/covers should be equipped with pressure relief, vacuum relief and _________. -- Answer โœ”โœ” flame- trap valves
  7. Hazardous gases can be composed of... -- Answer โœ”โœ” combustibles and explosive gases; asphyxiation-producing gases; poisonous or toxic gases
  8. In small concentrations hydrogen sulfide has a __________ odor. -- Answer โœ”โœ” rotten-egg
  9. Methane is a ____________________ and highly flammable gas which acts to deprive body tissues of oxygen and will not support life. -- Answer โœ”โœ” colorless, odorless, tasteless
  10. Chlorine is a heavy, non-combustible, ______________ gas with a pungent, irritating odor and very low electrical conductivity. -- Answer โœ”โœ” greenish-yellow
  11. 1 Liter = -- Answer โœ”โœ” 1000 milliliters (mL)
  1. 1 mL of water weights -- Answer โœ”โœ” 1 gram (g)
  2. 1 mg/L = -- Answer โœ”โœ” 1 parts per million (ppm) in water
  3. 7.48 gal = -- Answer โœ”โœ” 1 ft cubed
  4. 27 ft cubed = -- Answer โœ”โœ” 1 yard cubed
  5. 1 acre = -- Answer โœ”โœ” 43,560 ft squared
  6. 43,560 ft cubed = -- Answer โœ”โœ” 1 acre-ft
  7. 1 acre will treat approximately __________ lb BOD -- Answer โœ”โœ” 35
  8. 1 MGAD = -- Answer โœ”โœ” 23 gpd/ft cubed
  9. 1,000,000 gallons per day = -- Answer โœ”โœ” 1 MGD
  10. 8.34 lb in 1 MG of water = -- Answer โœ”โœ” 1 ppm (8. lb/8,340,000)
  11. 1 gallon of water weighs.. -- Answer โœ”โœ” 8.34 pounds
  12. 1 day = __________ minutes -- Answer โœ”โœ” 1440
  13. pie = -- Answer โœ”โœ” 3.
  14. Percent (%) formula is -- Answer โœ”โœ” Part/Whole X 100
  15. Circumference = -- Answer โœ”โœ” pie X diameter
  16. % reduction formula -- Answer โœ”โœ” incoming - outgoing/incoming X 100
  17. Who sets standards for wastewater treatment? -- Answer โœ”โœ” national, state and local government
  1. Different treatment plants have different requirements for wastewater treatment (true or false). -- Answer โœ”โœ” True
  2. Purpose of primary treatment -- Answer โœ”โœ” removes solids that readily settle or float
  3. Purpose of secondary treatment -- Answer โœ”โœ” microscopic living creatures (microorganisms) remove additional contaminants
  4. Purpose of advanced (tertiary) treatment -- Answer โœ”โœ” reduces specific contaminants such as suspended solids, ammonia or phosphorous to very low levels to achieve struct effluent standards
  5. What was the first major law to address water pollution? -- Answer โœ”โœ” The Federal Water Pollution Control Act of 1948
  6. What chapter of the Texas Water Code gives the TCEQ jurisdiction over the discharge of waste into adjacent water in the state? -- Answer โœ”โœ” Ch 26