TEXAS WASTEWATER CLASS C NEWEST ACTUAL EXAM COMPLETE 300 QESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED A+

1 | P a g e TEXAS WASTEWATER CLASS C NEWEST 2024-2025 ACTUAL EXAM COMPLETE 300 QESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED A+ What conditions should an operator observe in a well controlled activated sludge process? - ANSWER- surface turbulence/uniform roll pattern; foam/small amount of lightcolored, crisp foam; odors/mild, earthy; color/medium-brown What conditions should an operator observe in a well controlled clarifier? - ANSWER- 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 What type solids cannot go onto a trickling filter? - ANSWERlarge suspended solids Important factors to a well operating trickling filter... - ANSWER- continuous food supply, aerobic conditions and a moist zoogleal mass Basic elements of a trickling filter are... - ANSWER- floor and walls; distributor arms; underdrains and media 2 | P a g e What must be durable and provide enough surface for bacterial growth with a trickling filter? - ANSWER- filter media The zoogleal mass on a filter is composed mainly of what? - ANSWER- bacteria and algae The materials resulting from the stabilization of waste material as it passes through a trickling filter are... - ANSWER- water, nitrates and carbon dioxide What are zoogleal solids called that are washed off a trickling filter? - ANSWER- sloughings (which settle in the final clarifier) Units commonly used to measure the rate of hydraulic loading are... - ANSWER- lb/ft/day Units commonly used to measure the rate of organic loading include... - ANSWER- lb BOD/acre ft/day and lb BOD/1000 ft3/day 3 | P a g e Trickling filters may be classified as.... - ANSWER- high-rate; roughing; standard-rate The underdrain system of a standard rate trickling filter should be... - ANSWER- designed to flow half-full The recirculation ratio of a trickling filter has an effect on... - ANSWER- organic matter removal; odors; filter flies What test best indicates the efficiency of a trickling filter? - ANSWER- percent BOD removal Filter operational problems include... - ANSWER- ponding; filter flies (psychoda); odors Filter ponding may be caused by... - ANSWER- poor quality rock; excessive organic loading; inefficient primary clarifier Methods of controlling filter flies include... - ANSWER- flood the filter To control odors at a trickling filter plant, the operator can... - ANSWER- increase recirculation, practice good housekeeping and chlorinate the influent 4 | P a g e Clogged orifices on influent distributor arms may be corrected by... - ANSWER- cleaning and flushing Rotating biological contactors are usually covered to... - ANSWER- prevent algae growth on the media The rotating discs should be... - ANSWER- partially submerged in the wastewater Rotating biological contactors may be... - ANSWER- driven by electric motors or trapped air The biological growth on the disc of a rotating biological contactor should... - ANSWER- 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 The RBC (rotating biological contactor) unit must be preceded by a... - ANSWER- primary clarifier or fine screen A condition(s) that adversely affect(s) the operation of a rotating biological contactor is... - ANSWER- toxic materials from industrial wastes; hydrogen sulfide; high or low pH