Wastewater Treatment Operator Class I case studies
Wastewater Treatment Operator Class I · Put your knowledge to work in context.
The Wastewater Treatment Operator Class I credential is the entry-level certification for people who operate and monitor municipal or industrial wastewater treatment plants. It is typically pursued by new hires, maintenance staff moving into operations, collection-system workers, and students coming out of water/wastewater technology programs who need a recognized baseline of competence before taking on shift responsibility. The Wastewater Treatment Operator Class I case studies are 5 cases and about 4,676 words.
1Turbid Effluent and a Creeping Blanket at a 0.75 MGD Extended-Aeration Plant
A 0.75 MGD extended-aeration plant (aeration basin 0.30 MG) serves a town with a poultry-processing discharger. For ten days the effluent has been turbid and gray, with TSS 38 mg/L and BOD 22 mg/L, and the clarifier blanket has crept up to 1.5 ft with a 30-minute settled sludge volume of 430 mL/L.
863 words, about 4 min2Wet Well Entry for a Rag Blockage at a 1.5 MGD Plant
At a 1.5 MGD plant the single influent wet well is 14 ft deep with no alternate diversion. A rag mat has blinded the bar screen; the pump is cavitating and flow is down 40%.
968 words, about 5 min3Secondary Bypass During a Storm: DMR Reporting and the Affirmative Defense
A 2.0 MGD activated sludge plant has NPDES limits of 30 mg/L BOD and 30 mg/L TSS with 85% removal, reported on a monthly DMR. On a Saturday at 0900, during a 3-inch rain, influent peaked at 6.5 MGD.
925 words, about 5 min4Fecal Coliform Excursion at Peak Flow in an Undersized Contact Chamber
A 0.5 MGD plant disinfects with 12.5% sodium hypochlorite (about 1.24 lb available chlorine per gallon) fed to a chlorine contact chamber with 8,500 gallons of liquid volume and a baffling factor of 0.5. The permit requires a 1.0 mg/L residual after 20 minutes of contact and a fecal coliform limit of 200/100 mL monthly geometric mean.
948 words, about 5 min5Belt Press Cake Solids Drop and Filtrate Quality Fails
The belt filter press at a 1.2 MGD plant dewaters thickened waste activated sludge at 45,000 gal/day and 1.2% feed solids. Polymer is fed at 14 lb active polymer per dry ton, made up to a 0.4% solution.
972 words, about 5 min