Download Wastewater Treatment Practice Exam Questions and more Exams Science education in PDF only on Docsity! WASTEWATER/PRACTICE EXAM QUESTIONS When organic wastes are discharged to receiving waters, O2 is depleted by _____. - Answers -bacteria Hydrogen sulfide gives off an odor similar to____. - Answers -rotten eggs T/F: The highest concentration of algae growth in a facultative lagoon is usually observed near the top. - Answers -True Common hydraulic detention times for primary clarifiers range from ____ hours - Answers -2 - 3 hours T/F: Methane is produced in an anaeroibic digester and can be used as a fuel? - Answers -True T/F: The rock in a trickling filter is usually placed on a tile underdrain system. - Answers -True What is the purpose of heating and mixing a primary anaeroibic digester? - Answers -to increase the digestion rate T/F: Exhaust from a chlorinator room should be taken form floor level. - Answers -True T/F: Chlorine residual may be determined using the reagent _____ - Answers -diethyl-p- phenylene diamine (DPD) What test is typically never performed on wastewater influent? - Answers -fecal coliform 3 diseases potentially carried by wastewater are _____. - Answers -typhoid fever, disentery, cholera Immediate first aid for butrns is to ____. - Answers -flood with cold water What most likely causes an electic motor failure? - Answers -mopisture What mixed liquor characteristics indicate a healthy activated sludge process? - Answers -brown color, frothy appearance, and musty odor T/F: Algae is a plant life necessary for the proper functioning of a stabilization or oxidation pond. - Answers -True Chlorine gas is ? - Answers -heavier than air Considering the layout and flow diagram for the complete treament plant, oxidation ditch plants would be most similar to _____? - Answers -extended aeration The pressure against which a pump must operate is measured in terms of _____ - Answers -kPA (psi) T/F: Assuming aa constant suction head, the discharge of a centrifugal pump decreases with an increase in discharge head. - Answers -True T/F: The addition of chlorine, acid, carbon dioxide, or sulfuric acid will "lower" the pH of wastewater? - Answers -True T/F: Activated sludge generally "settle more slowly" than raw sludge. - Answers -True T/F: Controlling the sludge wasting rate by constant MLSS concentration involves maintaining a certain concentration of "volatile suspended solids in the reactor(aeration tanks) - Answers -True T/F: "Fungi" organisms should mot be present in a healthy lagoon treament system - Answers -True T/F: Under ice and snow cover, the BOD level in poinds will mormally "increase slowly". - Answers -True T/F: The rotational speed of the air-driven rotating biological contactor (RBC) is controlled by "air volume". - Answers -True T/F: chloramines are "combined chlorine." - Answers -True T/F: An "increase in organic matter" increases chlorine demand. - Answers -True When a high organic waste load reaches an activated sludge plant, the operator's first indicator is a decrease in - Answers -DO residual in the reactors (aeration tanks) Disaster planning is ____ - Answers -useful in reducing confusion in the event of a disaster. The gas most commonly associated with septic wastewater is - Answers -hydogen sulfide In electrical circuits, a ______ is used to reduce the voltage where necessary. - Answers -transformer What causes the greatest pipe friction loss? - Answers -Increasing the velocity of wastewater T/F: Denitrification is the most likely cause of rising sludge in clarifiers. - Answers -True
