Wastewater Class B Texas Exam 2024: 44 Questions and Answers, Exams of Water and Wastewater Engineering

Download Wastewater Class B Texas Exam 2024: 44 Questions and Answers and more Exams Water and Wastewater Engineering in PDF only on Docsity! Wastewater Class B Texas Exam 44 Questions and Answers 2024 Update. 1. In an activated sludge treatment system, primary treatment processes include the: - Correct answer Primary Clarifiers 2. In a washing grit remover, the grit is moved slowly by screw conveyors up an inclined channel in order to? - Correct answer Removal of Inorganic material from grit 3. An efficient primary clarifier is expected to remove? Of the influent settle able solids. - Correct answer 90% or above 4. Proper operation of a facultative pond system requires that: - Correct answer Adequate DO at surface at all times 5. The amount of organic matter removed by a trickling filter is mostly dependent on the recirculation ratio - Correct answer True 6. In an activated sludge treatment plant, a Sludge Volume Index (SVI) of 180 would indicate - Correct answer Bulking 7. The purpose of returning the solids from the bottom of the clarifier to the aeration tank in the activated sludge process is to - Correct answer Reseed the AB, Remove sludge from FC 8. Microscopic examination of a good-settling sludge should show a predominance of: - Correct answer Free swimmer rotifers stalked ciliates 9. When nitrification takes place in the activated sludge process, facultative bacteria use - Correct answer Dissolved oxygen (DO) or oxygen obtained from food materials such as sulfate or nitrate 10. In an activated sludge process, the results of a mixed liquor settling test indicate that the supernatant of the mixed liquor sample is clear, but the supernatant of the plant effluent sample is turbid. These test results indicate that the problem is occurring in the? - Correct answer Primary clarifiers 11. One indication that an anaerobic digestion facility is improving would be? - Correct answer Low C02 high Methane 12. The terms "low rate" and "high rate" when used in reference to the anaerobic digester refer to the rate of stabilization of the raw sludge? - Correct answer False 13. Besides disinfection, chlorination can be used in wastewater treatment processes to? - Correct answer Control odor, Reduce BOD, Control foaming, Aid in sludge 14. If released to atmospheric pressure, one part liquid chlorine will expand to about? - Correct answer 450ml 15. Anaerobically digested sludge should be applied to a drying bed to a depth of about? - Correct answer 8-12" 16. Sludge from a digester should be slowly drawn to a drying bed in order to? - Correct answer not to create a negative pressure in the anaerobic digester and to prevent coning of sludge 17. Direct aquifer recharge of treated effluent can be used to? - Correct answer Recharge Water supply, keep saline out of groundwater stop ground Substance P a g e 1 | 3 18. An exemption from filing monthly effluent reports with the TCEQ may be obtained if? - Correct answer under new construction, new plant, not running yet 19. A wastewater treatment plant would make use of? To remove small concentrations of dissolved organics from wastewater effluent - Correct answer Screens 20. The maximum design organic loading for stabilization ponds is 35 pounds of BOD per acre per day. An industry wants to construct a facility with projected flow of 50,000 god and an average BOD of 450 mg/l. A stabilization pond to serve this projected loading would need to be a minimum size of? - Correct answer 5.4 acres 21. A sewer construction project in rocky ground will require a 2 foot wide by 350 foot long trench with an average depth of 10 feet. The new pipe and select bedding material (hauled in) will occupy the bottom third of the trench. Assuming that the rest of the soil from the trench can be used for backfill, the cubic yards of spoil dirt which must be hauled away will be about? - Correct answer 86.41 22. Under average flow conditions, it takes 18 minutes for a 10-foot diameter lift station wet well to fill the 5 feet between the low water line and the level where the lead pump comes on. After the pump comes on, it runs for 11 minutes before turning off. These measurements indicate the average discharge rate of the pump is about: - Correct answer 430G 23. Samples of water are taken from both the inlet and outlet ends of a clarifier and poured into separate one-liter Inhofe cones. After settling for two hours, the sample of inlet water shows a settle able solids concentration of 10 mg/l while the sample of outlet water shows a settle able solids concentration of 2 mg/l. These measurements indicate the efficiency of the clarifier for settle able solids removal is, 80% - Correct answer 80% 24. At a flow of 1.7 MGD, a 50-foot diameter circular clarifier has an overflow rate of about? - Correct answer 866 god 25. In the F/M Ratio Formula, the "food" is represented by the - Correct answer BOD and COD 26. In the extended aeration activated sludge process, the biological mass is kept - Correct answer Mixed Liquor 27. The extended air activated sludge treatment process: - Correct answer Biological treatment for the removal of biodegradable organic wastes under aerobic conditions. 28. When a potable water supply is used to provide clean water to water seals on a wastewater pump, the installation should be made - Correct answer Next to Air Gap 29. In a wastewater collection system, manholes should be placed - Correct answer Points of change in alignment, grade, or size of sewer, at the intersection of all sewers and the end of all sewer lines 30. In the contact stabilization system of activated sludge treatment, the detention time in the contact zone is designed to? Other types of activated sludge treatment. - Correct answer to be less, or same. 31. Under the OSHA Hazard Communication Standard, an annual meeting to explain the Law and the company's written policy must be held for - Correct answer Employers that have hazardous chemicals in their workplaces are required 32. A combustible atmosphere, Methane & Hydrogen Sulfide - Correct answer Methane and hydrogen sulfide P a g e 2 | 3