ABC Class II Water Treatment case studies
ABC Class II Water Treatment · Put your knowledge to work in context.
The ABC Class II Water Treatment Operator certification is a mid-level credential for operators who treat drinking water and who are ready to take on more process responsibility than an entry-level Class I role. It is typically pursued by operators working in conventional surface water or groundwater plants who already understand basic plant flow and want to demonstrate competence in coagulation and flocculation control, filter performance, disinfection and residual maintenance, chemical feed systems, pumping and instrumentation, laboratory work and process-control math, regulatory reporting, and safety and emergency response. The ABC Class II Water Treatment case studies are 5 cases and about 3,957 words.
1Post-Storm Alum Overdose at a 4.0 MGD Conventional Plant
A 4.0 MGD conventional plant treats a reservoir that just took 2.8 in of rain in six hours. Raw turbidity climbed from 6 to 38 NTU and raw alkalinity fell from 68 to 42 mg/L as CaCO3 (pH 7.4).
768 words, about 4 min2Filter 2 Losing Media After the Water Warms Up
Filter 2 at a 2.4 MGD plant is 320 ft2, designed for 24 in of dual media and 55-hour runs at about 5 gpm/ft2. Over three weeks its runs have fallen to 21 hours, and effluent turbidity breaks through at 0.30 NTU by hour 18 while headloss is only 4.5 ft against an 8-ft terminal setpoint.
757 words, about 4 min3CT Compliance at Peak Flow - the Margin Disappears
A plant disinfects with free chlorine and must meet a state-required CT of 120 mg-min/L for 3-log Giardia inactivation at pH 8.0 and 10 C. The clearwell holds 250,000 gal with a baffling factor of 0.5.
790 words, about 4 min441 Hours Out of Turbidity Compliance, and an Overdue Calibration
During a 30-day month a Class II plant logged 720 hourly combined filter effluent (CFT) turbidity readings. Forty-one hours exceeded 0.3 NTU, clustered in two events: a 26-hour stretch after a filter was returned to service without filter-to-waste, and a 15-hour stretch during a coagulant feed upset.
779 words, about 4 min5Chlorine Leak, One Victim Down, and an Untrained Responder
On a July afternoon the chlorine room alarm sounds at a 3.5 MGD plant. A 1-ton chlorine container is leaking at the valve packing; a faint green-yellow haze hangs at floor level.
863 words, about 4 min