BASIC WASTEWATER OPERATOR PRACTICE CLASS 3 LATEST 2026/2027 ACTUAL EXAM QUESTIONS WITH CORRECT ANSWERS 100% VERIFIED GRADED A+

BASIC WASTEWATER OPERATOR
PRACTICE CLASS 3 LATEST
2026/2027 ACTUAL EXAM QUESTIONS
WITH CORRECT ANSWERS 100%
VERIFIED GRADED A+
1. Stalkedmciliatesm-
mCORRECTmANSWERmWhatmismthempredominantmorganismminmamhealthymActivatedmSludgem


TreatmentmPlant?



2. RepresentativemandmSub-samplesmtimemspacedmoverm15mminutesmapartm-
mCORRECTmANSWERmAmcompositemsamplemmustmbe?




3. 300mlm-mCORRECTmANSWERmWhatmismthemstandardmvolumemformamBODmsamplembottle?



4. Plugmvalvem-
mCORRECTmANSWERmIfmyoumhavemamlimemslurrymfeedmline,mwhatmismthembestmvalvemtomuse?




5. OldmSludgem-
mCORRECTmANSWERmIfmyoumnoticemampredominancemofmrotifersminmyourmactivatedmsludgem


samplemwhilemlookingmatmitmundermammicroscope,mwhatmdoesmthismindicate?



6. Settlingminmthemclarifiersm-
mCORRECTmANSWERmIfmyourmactivatedmsludgemplantmbeginsmtomnitrify,mwhatmconditionsmw


ouldmyoumexpectmtomdecrease?



7. 360mg/lm-mCORRECTmANSWERmCalculatemthemBODmgivenmtheminformation:
8. InitialmDO:m8.3
9. FinalmDO:m5.9
10. Millilitersmofmsamplemused:m2

,11. Bymmeasuringmthempumpmoutputm-
mCORRECTmANSWERmHowmdomyoumcalibratemamchemicalmfeedmpump?




12. H2SO4m-mCORRECTmANSWERmWhatmismthemchemicalmformulamformsulfuricmacid?



13. extendedmaerationm-
mCORRECTmANSWERmWhatmismthemmostmcommonmtypemofmActivatedmSludgempackagemplan


ts?



14. Increasemwastingm-
mCORRECTmANSWERmWhatmismthemmostmappropriatemmethodmofmreducingmthemF:MmRatio?




15. Unequalmairmdistributionmcausedmbymamblownmdiffuserm-
mCORRECTmANSWERmAnmoperatormnoticesmamportionmofmthemaerationmtankmwithmlargembub


blesmrisingmup.mWhatmismthemmostmlikelymproblem?



16. Thempressuremonmthemsuctionmsidemofmthempumpm-
mCORRECTmANSWERmWhatmismsuctionmlift?




17. 22.5mmg/lm-
mCORRECTmANSWERmThemprimarymeffluentmtomamRBCmsystemmism350mmg/lmBOD.mThemprim


arymunitmremovesm83%,mthemsecondarymunitmremovesm50%,mandmthemfinalmunitmremovesm2
5%.mWhatmismthemBODmleavingmthemfinalmunitmofmthemRBCmtrain?



18. Decreasemthemlagmtimemformpumpmoperationmbymmovingmthemfloatsmclosermtogetherm-
mCORRECTmANSWERmTheminfluentmtomthemtreatmentmplantmismseptic.mItmismdeterminedmtha


tmitmismcomingmfrommamliftmstationmupstreammfrommthemplant.mWhatmshouldmthemoperatorm
do?

, 19. Tomprotectmchemicalsmthatmaremsensitivemtomlightm-
mCORRECTmANSWERmWhatmismthempurposemofmambermstoragembottles?




20. 24mdaysm-mCORRECTmANSWERmCalculatemSRT
21. GIVEN:mMixedmliquormsuspendedmsolidsm(MLSS)m=m2400mg/l
22. Aerationmbasinmvolumem=m35,000mgallonsm=m0.0350mmillionmgallonsm(MG)
23. Wastemactivatedmsludgem(WAS)mconcentrationm=m3500mg/l
24. Wastemactivatedmsludgem(WAS)mflowratem=m0.001MGD



25. Horizontalm&mHorizontalm-mCORRECTmANSWERmHowmshouldmam1-
tonmchlorinemcylindermbemmoved?



26. 0.68m-mCORRECTmANSWERmCalculatemF:Mmratio
27. GIVEN:mInfluentmBOD5m=m290mg/l
28. InfluentmFlowm=m5.0MGD
29. AerationmbasinmMLSSm=m2650mmg/l
30. Aerationmbasinmvolumem=m0.8MG



31. Cloggedmimpellerm-
mCORRECTmANSWERmWhatmwouldmmostmlikelymcausemamsubmersiblempumpmtomhavemanmA


MPmreadingmthatmismabovemthemoptimummlevel?



32. Statorm-mCORRECTmANSWERmWhichmofmthemfollowingmaremnon-
movingmpartsmofmamrunningmmotor?



33. 225m-mCORRECTmANSWERmCalculatemSVI
34. GIVEN:m30mminutemsettlingmtestm=m1800mlminmam2000mlmcontainer
35. MLSS:m4000mg/L