WasteWater Operator class C exam practice review 2022/2023

When Chlorine is combined with water what type of pipe should be used? A. Ductile iron B. Asbestos concrete C. PVC D. Carbon Steel - ANSWER C. PVC A good settling sludge would consist of what type of protozoa? A. Rotifers and nematodes B. Amoebas and Flagellates C. Stalked ciliates and mastagoria D. Free swimmers and stalk ciliates - ANSWER D. Free swimmers and stalk ciliates What is Phenolphylein used for in titration A. Oxidizer B. Indicator C. Acid reducer to lower pH D. Applicator - ANSWER B. Indicator Your plant has an influent of 220 BOD and 163 TSS, and an effluent of 10 BOD, and 6 TSS. What is the BOD removal efficiency in your plant? A. 92% B. 94% C. 95% D. 96% - ANSWER C. 95% You suspect your anaerobic digester is going sour. What is the best way to verify its condition? A. pH B. Foam type C. VA/ALK ratio D. DO - ANSWER C. VA/ALK ratio Before operating any piece of equipment what should be done? A. Lock out Tag out (remember, safety first!) B. Read O & M manual C. Read manufacturers manual D. Notify supervisor - ANSWER C. Read manufacturers manual Detritus is noticed in your grit channel. What is the problem? A. Velocity too fast with short D/T B. Velocity too low with long D/T C. Short circuiting D. Density currents - ANSWER B. Velocity too low with long D/T What is considered normal operation of an aerobic digester? A. Fill react B. Skim off foam when needed C. Settle and Decant as needed D. Feed only during low flow or constant when the sun is out - ANSWER C. Settle and Decant as needed A plant with a flow of 1 MGD should be monitored A. Continuously B. Intermittently C. Daily D. Every four hours depending on surface load - ANSWER A. Continuously What do total solids consist of? A. Dissolved and settleable B. Floatable and settlable C. Suspended and dissolved D. Settlable and nonsettleable - ANSWER C. Suspended and dissolved What would cause excessive wear on bearing? A. Misalignment B. Reduced Oil due to low viscosity C. Blow seal D. Over tubercation - ANSWER A. Misalignment Amperometric titration is used to measure A. Dissolved solids B. Chlorine residual C. Colloids D. Emulsions - ANSWER B. Chlorine residual What growth phase is an aerobic digester operated in. A. Log B. Lag C. Endogenous respiration D. Declining phase - ANSWER C. Endogenous respiration If excessive pressure builds up in a chlorine tank due to excessive heat. What will prevent explosions? A. Valve seat adjustments B. Heat reducing valve C. Fusible plug D. Check valve - ANSWER C. Fusible plug You notice that your bearings are excessively hot on a pump, why? A. Ambient temperature too high B. Over lubrication C. Oil seal blown D. Discharge rate too low - ANSWER B. Over lubrication Where can you gain access for collection system maintenance? A. Lift station B. Force main C. Man hole D. Gravity main - ANSWER C. Man hole Low DO and nutrient deficiency will promote the growth of what? A. Rotifers B. Filamentous bacteria C. Spirillium D. Amoebas - ANSWER B. Filamentous bacteria When charging a lead-acid type battery for a composite sampler, what dangerous gas could be produced? A. Hydrogen B. Oxygen C. Hydrogen sulfide D. Cyanide - ANSWER A. Hydrogen What is the best method in dealing with a chemical spill? A. Contain and clean up B. Saw dust and kitty litter C. Foam congaing super trimethyl bromine D. Flood with water - ANSWER A. Contain and clean up There is septic wastewater entering your primary clarifier. What is the problem? A. Aerobic conditions in the collections system B. Lift station pumps operating on short cycles C. Anaerobic conditions in the collections systems D. High flows due to a low MCRT - ANSWER C. Anaerobic condition in the collections system Which of the following substances is highly viscous and very slippery? A. Calcium hypochlorite B. Calcium oxide C. Potassium permanganate D. Polymer - ANSWER D. Polymer If you pump green sludge to a drying bed what chemical should be applied? A. Polymer B. Lime C. Cl2 D. Alum - ANSWER B. Lime Chlorine leaks can be detected by? A. ISCBA B. Ammonia solution with Q-Tip C. Alcohol vapor D. Spray with mist of water - ANSWER B. Ammonia solution with Q-Tip What takes place in the stabilization tank in a contact stabilization plant? A. Adsorption B. Clarification C. BNR D. Absorption - ANSWER D. Absorption Why is an aerobic digester covered? A. Hold in gas B. Protect for contaminants C. Reduce radiation D. Protect from cold weather - ANSWER D. Protect from cold weather Which of the following would you not use a grab sample on? A. BOD B. DO C. pH D. Temp - ANSWER A. BOD Staffing is based on what? A. Budget B. Flow and type of treatment C. City Hall D. Chief operator - ANSWER B. Flow and type of treatment What condition does an operator have the least amount of control over? A. Flow B. Wasting Rate