Treatment Process
33%of exam
Laboratory Analysis
16%of exam
Equipment Operation
23%of exam
Source Water
15%of exam
Surface WaterGroundwaterWatershedSeasonal ChangesSource Picker
Safety + Administration
13%of exam
Quick Facts
- Exam body
- WPI / states
- Questions
- 100 scored
- Pretest
- Up to 10
- Time
- 3 hours
- Pass
- Often 70%
- Calculations
- 12%
- Cognitive
- 70% application
- Formula sheet
- Provided
Treatment Train Order
Coagulate, grow, settle, filter, disinfect.
CoagulationFlocculationSedimentationFiltrationDisinfection
Coagulation vs Flocculation
Coagulation
- Rapid mix
- Neutralizes charge
- Chemical dose
Flocculation
- Slow mix
- Builds floc
- Contact time
Dose first, grow second
Process Picker
- Fine particles→Coagulation(Neutralize charge)
- Weak floc→Flocculation(Gentle mixing)
- Heavy floc→Sedimentation(Settle solids)
- Turbid effluent→Filtration(Polish water)
- Pathogen risk→Disinfection(Meet CT)
- Low residual→Increase dose(Check demand)
Treatment Train
- Screening
- Remove large debris
- Coagulation
- Destabilize particles
- Flocculation
- Build settleable floc
- Sedimentation
- Gravity settling
- Filtration
- Polish turbidity
- Disinfection
- Inactivate pathogens
- Clearwell
- Storage plus contact
- Residual
- Distribution protection
Chlorine Balance
Dose minus demand leaves residual.
DoseDemandResidualCT
Dose vs Residual
Dose
- Chemical applied
- Before demand
- Operator controlled
Residual
- Chemical remaining
- After demand
- Compliance measured
Demand consumes dose
Coagulation Control
- Alum
- Common coagulant
- Ferric salts
- Iron coagulants
- Polymer
- Coagulant aid
- pH
- Controls charge
- Alkalinity
- Buffers pH
- Rapid mix
- Chemical dispersion
- Zeta potential
- Particle charge
- Streaming current
- Charge monitor
Free vs Combined Chlorine
Free
- Stronger disinfectant
- Shorter persistence
- Breakpoint target
Combined
- Weaker disinfectant
- Longer persistence
- Chloramine residual
Free kills faster
Filtration
- Rapid sand
- Conventional filter
- Slow sand
- Biological layer
- Anthracite
- Coarse top media
- Headloss
- Clogging indicator
- Breakthrough
- Turbidity spike
- Backwash
- Clean filter bed
- Ripening
- Postwash stabilization
- Filter aid
- Improves capture
Disinfection
- CT
- Concentration times time
- T10
- Effective contact time
- Demand
- Dose minus residual
- Free chlorine
- Strong primary
- Chloramine
- Longer residual
- Ozone
- Strong oxidant
- UV
- No residual
- DBPs
- Disinfection byproducts
Operator Math
- lbs/day
- Dose x flow x 8.34
- Dose
- lbs/day / flow / 8.34
- Demand
- Dose minus residual
- Detention
- Volume divided flow
- Pressure
- Feet divided 2.31
- Volume
- Area times depth
- Percent
- Part divided whole
- MGD
- Million gallons daily
Lab Quality Checks
Calibrate, blank, duplicate, document.
CalibrationBlankDuplicateChain custody
Recall vs Application
Recall
- Definitions
- Recognition
- 30% exam
Application
- Calculations
- Troubleshooting
- 70% exam
Practice decisions most
Data Picker
- Coagulant dose→Jar test
- Filter health→Turbidity trend
- Disinfection proof→Residual + time
- Corrosion control→pH/alkalinity
- Instrument drift→Calibration standard
- Questionable result→Duplicate sample
Routine Tests
- Turbidity
- Particle cloudiness
- pH
- Acid/base condition
- Alkalinity
- Buffer capacity
- Hardness
- Calcium/magnesium
- Color
- Organic signal
- Temperature
- Reaction speed
- Residual
- Disinfectant remaining
- Bacteria
- Microbial indicator
Jar Testing
- Purpose
- Find best dose
- Rapid mix
- Simulate coagulation
- Slow mix
- Simulate flocculation
- Settling
- Compare clarity
- pH series
- Find optimum
- Turbidity check
- Measure performance
- Sludge volume
- Settling clue
- Plant trial
- Confirm cautiously
Sampling + QA
- Grab sample
- Instant condition
- Composite
- Time blended
- Chain custody
- Sample tracking
- Preservation
- Protect integrity
- Calibration
- Instrument accuracy
- Blank
- Contamination check
- Duplicate
- Precision check
- Standard
- Known value
Equipment Picker
- No flow→Check pump(Prime first)
- High amps→Check load(Motor stress)
- Vibration→Check bearings(Alignment clue)
- Erratic analyzer→Clean/calibrate(Verify grab)
- Remote alarm→SCADA trend(Confirm field)
- Wrong chemical feed→Stroke setting(Verify drawdown)
Pumps + Motors
- Centrifugal
- Flow by velocity
- Positive displacement
- Fixed volume
- Cavitation
- Vapor bubble damage
- Priming
- Remove air
- Seal
- Leak control
- Bearing
- Supports rotation
- Amps
- Motor load
- VFD
- Speed control
Controls + Instruments
- SCADA
- Remote monitoring
- PLC
- Local controller
- Flow meter
- Measure flow
- Analyzer
- Online chemistry
- Telemetry
- Signal transmission
- Alarm
- Abnormal condition
- Setpoint
- Control target
- Trending
- Pattern review
Surface vs Groundwater
Surface
- Turbidity swings
- Pathogen exposure
- Watershed driven
Groundwater
- Stable quality
- Minerals common
- Wellhead driven
Source controls treatment
Source Water
- Surface water
- Rapidly variable
- Groundwater
- Mineral rich
- GUI
- Surface influence
- Watershed
- Drainage area
- Algae
- Taste/odor risk
- Runoff
- Turbidity spike
- Wellhead
- Groundwater protection
- Reservoir turnover
- Seasonal mixing
Safety Order
Read SDS before handling chemicals.
SDSPPEVentilationSpill plan
MCL vs MCLG
MCL
- Enforceable standard
- Feasibility considered
- Compliance limit
MCLG
- Health goal
- Not enforceable
- Safety margin
MCL is enforceable
Safety Picker
- Chemical unloading→SDS + PPE
- Tank entry→Confined permit
- Repair energized gear→LOTO
- Water violation→Public notice
- Cyber alert→Incident plan
- Process upset→Emergency SOP
Safety + Compliance
- SDS
- Chemical hazards
- PPE
- Worker protection
- LOTO
- Energy isolation
- Confined space
- Permit entry
- SOP
- Standard procedure
- Public notice
- Violation communication
- CCR
- Annual water report
- MCL
- Enforceable limit
Common Traps
Dose Is Not Residual
Chemical added ≠ Chemical remaining
Turbidity Is Not Color
Suspended particles ≠ Dissolved appearance
Detention Is Not CT
Hydraulic time ≠ Disinfection exposure
Calibration Is Not Cleaning
Adjusts accuracy ≠ Removes fouling
MCL Is Not MCLG
Legal limit ≠ Health target
SOP Is Not SDS
Work procedure ≠ Chemical hazard
Last Minute
- 1.Treatment Process = 33%
- 2.Equipment O&M = 23%
- 3.Lab Analysis = 16%
- 4.Source Water = 15%
- 5.Safety/Admin = 13%
- 6.Dose - demand = residual
- 7.CT = concentration x time
- 8.8.34 converts mg/L-MGD
- 9.MCL enforceable; MCLG goal
- 10.Jar tests guide dosing
- 11.Surface water changes quickly
- 12.Use SDS before chemicals
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