Grade 2 Wastewater Treatment Operator Practice Exam Q&A 2024/2025

Grade 2 Wastewater Treatment Operator Practice Exam Q&A 2024/2025 What is the methane content in a properly operating anaerobic digester? 65 to 70% by volume What will the addition of chlorine gas do to the pH of wastewater? decrease the pH What is the purpose of a Parshall Flume? Measure the flow rate What is the typical removal efficency of settleable solids in a primary clarifier? 95 to 99% Which of the follwing is true about pumoing scum from a primary clarifier? scum causes more piping problems than other substances pumped at a wastewater treatment plant What might cause thick billows of white sudsy foam in the aeration tank? MLSS is too low What does the M in F/M ratio represent? The mixed liquor volatile suspended solids in the aeration tank In general, how will warmer temp affect the settling rate of solids in a clarifer? Increase the settling rate What could happen if the digester gas is mixed with air(85 to 95% by volume)? Cause an explosion How will algae impact the chlorine demand in the pond effluent? increase the chlorine demand Which of the following is true about a positive displacement pump? it must never be started with the discharge valve closed What is true about the F/M ratio? the volume of the secondary clarifier is not needed to determine the f/m ratio Which of the following is one of the basic rules of lab work? never pipet hazardous material with your mouth, even if the pipet has been sterialized What is the recirculation ratio for a trickling filter? Qr/Q Which of the following is true about COD and BOD? they are indirect measurements of the organic content in the influent What is the purpose of the grit channel? remove heavy inorganic waste Which of the following is true about the extended aeration process? it does not produce as much waste sludge as other processes What is the correct formula for solids in raw wastewater? Non settleable solids + settleable solids = total suspended solids What is freeboard in a waste stabilization pond? the vertical distance from normal water surface to the top of the levee What is one of the requirements for a BOD test? The BOD bottle should be completely filled to the top What should be scheduled every 3 months for a flamer arrester in an anaerobic digester? maintenance What is common practice in an activated sludge process? recirculate activated sludge Prior to entering a permit-required confined space, what should you verify? a standby person should be located outside the entrance to the confined space, while another person should be within sight or call of the standby person What is a common way to determine the organic strength of wastes in the influent? test for the biochemical oxygen demand What should you do if you are mildly exposed to chlorine gas? immediately evacuate the contaminated area, remian calm, keep warm. breath lightly, avoid coughing What are the main sources of domestic sewage in the collection system? household and commercial establishments Why is it important to maintain a horizontal weir in a clarifier? to prevent short circuiting What are mostly removed in the grit channel?