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A comprehensive guide to the tceq wastewater license exam, covering essential topics such as the water use cycle, wastewater characteristics, treatment processes, and relevant regulations. It includes numerous questions and answers, offering valuable insights into the exam's content and helping prepare individuals for the licensing process.
Typology: Exams
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What are the steps of the Water Use Cycle? - Correct Answers ✅Environment --> Water Treatment --> Water Distribution System --> Customer Use --> Wastewater Collection System --> Wastewater Treatment --> Environment What are the benefits of the collection system? - Correct Answers ✅- Removal of health hazards
What are the four wastewater characteristics? - Correct Answers ✅Physical, Chemical, Bacteriological, and Radiological Domestic wastewater is ___% water and ___% solids - Correct Answers ✅99.9% water, 0.1% solids Settleable solids - Correct Answers ✅Suspended solids that will settle when wastewater flow is still or slow moving What is the pH scale range? - Correct Answers ✅0 (most acidic) to 14 (most basic), 7 is neutral Does septic or freshwater have a lower pH? Why? - Correct Answers ✅Septic has lower pH due to volatile acids formed from wastewater decomposition What is Hydrogen Sulfide (H2S)? When does it occur? - Correct Answers ✅A colorless, toxic, and flammable gas that resembles the smell of rotten eggs. It results from the bacterial breakdown of organic matter in the absence of oxygen. It is heavier than air.
What is Methane? (CH4) What percentage of methane is in digester gas? - Correct Answers ✅A colorless, odorless, and highly flammable gas. Methane is an asphyxiant and is lighter than air. Digester gas contains 65% methane and is used for heating fuel or operating equipment. What is carbon dioxide? (CO2) - Correct Answers ✅A colorless, odorless gas that has a suffocating effect. When inhaled at higher than normal concentrations, it can produce a sour taste in the mouth and a stinging sensation in the nose and throat. What is carbon monoxide? (CO) - Correct Answers ✅A colorless, odorless, and tasteless gas Why is oil and grease a concern if present in wastewater? - Correct Answers ✅It may cause explosions, fires, line blockages, and odor What are chlorides and why are excessive chlorides in wastewater bad? - Correct Answers ✅Excessive chlorides interfere with treatment processes, especially trickling filters. They also affect laboratory tests. What does the BOD test measure? - Correct Answers ✅It measures wastewater strength and the oxygen depleting
effect of wastewater effluent on the receiving stream. Specifically, it indicates the amount of organic matter that can be oxidized by biological and chemical action in five days at 20 degrees Celsius. What are pathogens? What are two viral diseases that could be carried in wastewater? - Correct Answers ✅Polio and infectious hepatitis What are precautions individuals can take to protect against pathogens in the collection system? How do communities overall prevent waterborne disease? - Correct Answers ✅- Wear cut-resistant gloves
When can TCEQ revoke an operator's permit? - Correct Answers ✅If the operator:
TCEQ's goals regarding water pollution control are: - Correct Answers ✅- To maintain state water quality
Any plant with a design flow above ___ MGD is required to install instrumentation for continuous flow totalizing - Correct Answers ✅0.5 MGD What does preliminary treatment do? - Correct Answers ✅It protects the treatment system from large obstructions in the raw influent, unnecessary wear on process equipment, and fluctuations of flow and pollutant strength What does primary treatment do? It should remove what percentage of settleable solids, suspended solids, BOD, and total organic matter? - Correct Answers ✅Primary treatment is the removal of settleable solids from the raw wastewater It should remove:
What is the activated sludge process? - Correct Answers ✅Uses living organisms in an oxygen-rich environment to remove organic wastes from wastewater What is the oxygen rate in an activated sludge system? - Correct Answers ✅2- What is the purpose of Return Activated Sludge (RAS)? - Correct Answers ✅Pumps continuously send RAS to the aeration tank, which reseeds the biological reaction in the aeration tank and removes accumulating sludge from the clarifier What is F/M? - Correct Answers ✅The ratio of the amount of food applied per day to the microorganisms in the aeration tanks What is Gould Sludge Age? - Correct Answers ✅How long, in days, a pound of solids stays in the aerator What is Mean Cell Residence Time? - Correct Answers ✅Estimates how long the living cells are kept in the plant What are the five important controls for activated sludge plants? - Correct Answers ✅- Dissolved Oxygen
What are the five basic parts in a trickling filter? - Correct Answers ✅- Filter floor
What can advanced treatment processes do that secondary treatment can't? - Correct Answers ✅Advanced treatment processes strive to provide a higher removal level of specific compounds, suspended solids, and oxygen-demanding materials that cannot be achieved through secondary treatment alone. In advanced treatment processes, what is the most important factor affecting filter performance? - Correct Answers ✅the quality of the secondary effluent being applied to the filter - low in solids In advanced treatment, a filtration process should remove about ____ of the TSS applied - Correct Answers ✅70%-90% What is adsorption? - Correct Answers ✅When a material clings to the surface of a second material, usually a solid What is primary sludge and its moisture content? - Correct Answers ✅Suspended solids that have been settled out in primary sedimentation tanks or primary clarifiers. The moisture content is 94-96% moisture (4-6% solids) What is the gas composition in a well-run digester? - Correct Answers ✅65-75% methane, and 25-35% carbon dioxide
What does disinfection do and what are the different types? - Correct Answers ✅Disinfection is the primary mechanism for inactivating and destroying pathogenic organisms in wastewater.
BOD analysis should begin no later than after __ hours of sampling (after being refrigerated to __C) to be assured of representative results - Correct Answers ✅6 hours, 6 degrees Celsius What is the holding time for TSS after being collected in a wastewater treatment plant? - Correct Answers ✅7 days What is the definition of a flow-weighted composite sample? - Correct Answers ✅A combination of portions of samples collected at regular intervals and combined according to flow The Sludge Volume Index (SVI) should range from ________. What does being out of this range mean? - Correct Answers ✅70 to 150. Under 70 = sludge is settling so rapidly that poor clarification will result. Over 150 = there becomes a tendency for the sludge to begin bulking and solids sent over the weir of the final clarifier What is the preferred Guild Sludge Age (GSA) for activated sludge? - Correct Answers ✅5-10 days for conventional and complete mix plants,
25 days for extended aeration plant
Operators should be concerned with what four types of microorganisms? - Correct Answers ✅Amoeboids, flagellates, ciliates, and rotifers Name the presence of the four different microorganisms in good quality sludge with good settling in order from most prominent to least prominent - Correct Answers ✅1. Free swimming ciliates
inverse relationship. As the water gets colder, it is capable of holding more dissolved oxygen. As it gets warmer, the ability to hold dissolved oxygen decreases The Clean Water Act requires WWTPs to achieve greater than or equal to __% removal of TSS and BOD - Correct Answers ✅85% What is the imhoff cone used to measure? - Correct Answers ✅Settleable solids What are different types of preliminary treatment? - Correct Answers ✅racks, screens, grinders, grit channels What is grit and why is it removed during preliminary treatment? - Correct Answers ✅Grit consists of non- biodegradable particles including sand, , rocks, coffee grounds, etc. It is removed to remove the heavy, inorganic waste that doesn't break down during treatment and to prevent equipment damage. What are coagulants? What is flocculation? - Correct Answers ✅Coagulants are chemicals that cause very fine particles to clump together into larger particles
Flocculation is the gathering together of fine particles after coagulation to form larger particles What are colloidal particles? What can be used to get rid of them? - Correct Answers ✅Very small particles that carry an electric charge which makes it very difficult for them to flocculate and settle. Coagulants can be used to neutralize the charge and enable them to flock together. What are the two main parameters an operator should use to ensure proper settling occurs in the primary clarifier? What are the definitions of each? - Correct Answers ✅1. Surface overflow rate: The representation of the flow rate as it relates to the surface area of the clarifier. It is used to determine if clarifiers are hydraulically over or under loaded
the filter is inadequate. It occurs due to excessive slime growths, trash, or media breakdown What happens if recirculation rates in a trickling filter are too low? - Correct Answers ✅it can lead to reduced BOD removal, ponding, and filter fly reproduction What factor determines chlorine dosage? - Correct Answers ✅Allowed bacteria level in the plant effluent What is chlorine demand? - Correct Answers ✅The difference between the dose and the residual concentration What is free chlorine? - Correct Answers ✅The combination of dissolved chlorine gas, hypochlorous acid, and hypochlorite ion How can a chlorine leak be located or detected? - Correct Answers ✅Using an ammonia soaked rag or spray bottle What are the names of cold, medium, and hot temperature bacteria, respectively? - Correct Answers ✅Psychrophilic, mesophilic, and thermophilic
Solids remain in an anaerobic digester for ___ days - Correct Answers ✅15-20 days. Each time sludge is pumped into a digester, an equal volume of sludge is transferred to the secondary digester What are four methods of dewatering stabilized sludge? - Correct Answers ✅belt press, centrifuge, plate and frame press, drying beds and lagoons What can an operator do to reduce the effluent BOD of a Trickling Filter? - Correct Answers ✅Raise recirculation rate. What do evaporators in the chlorine feed system do? - Correct Answers ✅Convert liquid chlorine to gaseous chlorine for use by chlorinators What is the purpose of recirculating trickling filter effluent? - Correct Answers ✅To keep a constant hydraulic load on the trickling filter The Clean Water Act (CWA) defines secondary treatment as a wastewater treatment plant that consistently produces an effluent that contains no more than _____BOD and ______ Suspended Solids based on a _____day average - Correct Answers ✅30 mg/L, 30 mg/L, and 30 day average
What is the best chemical to use for pond odor control? - Correct Answers ✅Sodium Nitrate When operating a Rotating Biological Contactor plant to nitrify incoming ammonia, the DO levels in the nitrification stage should be maintained in the range of: - Correct Answers ✅2.0 - 3.5 mg/L. Wastewater flowing through a grit channel should ideally flow at a velocity of: - Correct Answers ✅1 fps. Each stage of the RBC process should have sufficient volume to provide for a contact time of about: - Correct Answers ✅ 1 hour When might surface aerators be necessary when operating a pond? - Correct Answers ✅During night, during periods of organic overload, and during cold seasons What should an operator do if an anaerobic digester is noticing that the volatile acid/alkalinity ratio is increasing? - Correct Answers ✅To cure a souring digester, the operator should reduce the sludge feed and removal rate from the digester and ensure adequate mixing is occurring
What does the outlet baffle do on a pond? - Correct Answers ✅Prevents surface debris from leaving the pond. Floatable scum is usually removed from wastewater in the: - Correct Answers ✅Primary clarifier What must be considered when designing a No Discharge pond system? - Correct Answers ✅percolation rates and evaporation rates How can the operator control the scum blanket in an anaerobic digester? - Correct Answers ✅proper mixing and heat control What adverse condition may be created if the pressure relief or the air relief operates on an anaerobic digester? - Correct Answers ✅an explosive condition can be created by the mixture of methane and air. What problem is indicated by organic material in removed grit? - Correct Answers ✅that flow velocities are too low in the grit channel.