HI Water/WW Operator case studies
HI Water/WW Operator · Put your knowledge to work in context.
The Hawaii Water Treatment Plant and Wastewater Treatment Plant Operator Certification is administered within the Hawaii State Department of Health (HDOH) framework, with drinking water operator certification handled under the Safe Drinking Water Branch and wastewater operator certification under the Wastewater Branch. This study page is for candidates preparing for either pathway - water treatment and distribution, or wastewater treatment and collection - and for operators already in the field who need a structured review. The HI Water/WW Operator case studies are 5 cases and about 3,956 words.
1Filter Run Collapse After a Storm Event
A 3.5-mgd conventional surface water plant treats a reservoir source with aluminum sulfate coagulation, flocculation, sedimentation, and four dual-media filters of 350 ft² each. Free chlorine is applied ahead of a 250,000-gallon baffled clearwell.
801 words, about 4 min2Coliform Hits at the End of a Dead-End Main
A 4,200-connection community chlorinates with free chlorine and stores water in a 300,000-gallon elevated steel tank that turns over about once every two days. A 9,500-ft length of 12-inch asbestos-cement main dead-ends after serving 40 homes and one small market.
828 words, about 4 min3Nitrification Slides After a New Industrial Discharge
A 1.8-mgd extended-aeration activated sludge plant has 1.2 MG of aeration volume, two 75-hp blowers with one on standby, and internal recycle for denitrification. Permit limits are 4.0 mg/L monthly average ammonia-N, 30 mg/L TSS and 30 mg/L BOD.
730 words, about 4 min4Duplex Lift Station Loses a Pump Ahead of a Storm
A duplex submersible lift station serves 900 homes through a 6-inch force main 2,200 ft long, with 22 ft of static lift and a normal total dynamic head of about 48 ft. Each pump is rated 300 gpm.
805 words, about 4 min5A Pressure Drop, a Plating Shop, and a Complaint About Chemical Taste
An 8-inch distribution main serves a business park that includes a metal plating shop on a 2-inch service, a car wash, and a restaurant. The plating shop has no backflow assembly; it was installed before the cross-connection ordinance and was never retrofitted.
792 words, about 4 min