ABC Class II Water Treatment flashcards
ABC Class II Water Treatment · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Turbidity
- Turbidity measures light scattering by suspended particles in water; it is reported in nephelometric turbidity units and can indicate treatment performance and microbial risk.
- Total organic carbon
- TOC measures organic carbon in source water; higher TOC increases coagulant demand, disinfectant demand, and formation potential for disinfection byproducts.
- Groundwater under direct influence
- Groundwater under the direct influence of surface water is groundwater contaminated by surface water via preferential pathways; it requires surface-water-type treatment and monitoring.
- Sanitary survey
- A sanitary survey is a structured inspection of a water system's source, treatment, storage, and distribution to identify contamination risks and compliance deficiencies.
- Jar test
- A jar test simulates coagulation, flocculation, and settling at several coagulant doses and pH values to select the best treatment conditions.
- Coagulation
- Coagulation destabilizes suspended particles by neutralizing electrical charges so they can collide and form larger flocs.
- Flocculation
- Flocculation is gentle mixing that encourages destabilized particles to collide and grow into settleable flocs without breaking them apart.
- Surface overflow rate
- Surface overflow rate equals flow divided by settling basin surface area; particles with settling velocity greater than this rate are ideally removed.
- Filter ripening
- Filter ripening is the period after backwash when effluent turbidity is elevated before the media captures particles effectively again.
- Backwash
- Backwash reverses flow through a filter to expand media and flush captured solids; adequate expansion and duration restore filter capacity.
- Breakthrough
- Breakthrough is the passage of particles into filtered water before terminal headloss, indicated by rising effluent turbidity.
- Uniformity coefficient
- The uniformity coefficient is d60 divided by d10 of filter media; it describes particle-size gradation and affects filtration and backwash.
- CT
- CT is disinfectant concentration in mg/L multiplied by contact time in minutes; required CT varies with disinfectant, pH, temperature, and pathogen.
- Chlorine demand
- Chlorine demand is the amount of chlorine consumed by water constituents during contact; applied dose minus residual after contact equals demand.
- Chloramination
- Chloramination uses chlorine and ammonia to form chloramines; it provides a stable residual but is a weaker primary disinfectant than free chlorine.
- Disinfection byproducts
- Disinfection byproducts such as trihalomethanes and haloacetic acids form when disinfectants react with organic matter; their concentrations are regulated.
- Chemical feed rate formula
- Feed rate in pounds per day equals flow in million gallons per day times dose in mg/L times 8.34.
- Secondary containment
- Secondary containment surrounds chemical storage to capture leaks and spills; it should hold at least the volume of the largest container.
- Sodium hypochlorite storage
- Sodium hypochlorite loses strength with heat, light, and age; store it cool, dark, ventilated, and rotate stock to maintain dose accuracy.
- NPSH
- Net positive suction head is the absolute pressure margin at a pump suction; insufficient NPSH available causes cavitation and impeller damage.
- Affinity laws
- For a centrifugal pump at constant impeller diameter, flow varies with speed, head with speed squared, and power with speed cubed.
- Check valve
- A check valve allows flow in one direction only and closes to prevent backflow when forward flow stops.
- Chain of custody
- Chain of custody documents each sample's possession, transfer, and condition to preserve legal and regulatory defensibility of analytical results.
- DPD method
- The DPD colorimetric method measures free and total chlorine by color development; turbidity and strong oxidants can interfere with results.
- Detention time formula
- Detention time equals basin volume divided by flow rate; units must match, such as gallons divided by gallons per minute.
- Log removal
- Log removal equals log10 of influent concentration divided by effluent concentration; 2-log removal is 99 percent and 3-log is 99.9 percent.
- Maximum contaminant level
- An MCL is the highest contaminant concentration allowed in drinking water under federal regulations; it is an enforceable primary standard.
- Consumer Confidence Report
- The Consumer Confidence Report is an annual water quality report that lists detected contaminants, sources, and health information for customers.
- Public notification tiers
- Public notification Tier 1 is for acute violations and is issued within 24 hours; Tier 2 within 30 days; Tier 3 within 90 days.
- Confined space entry
- Confined space entry requires a permit, atmospheric testing for oxygen and hazardous gases, an attendant, and a rescue plan.
- Chlorine gas leak response
- For a chlorine gas leak, evacuate upwind, notify responders, and use supplied-air respiratory protection; never enter without proper protection.
- Safety data sheet
- A Safety Data Sheet provides chemical hazards, safe handling, PPE, first aid, and spill response information for a hazardous chemical.