Basic Wastewater Operator Practice Exam Questions With Correct Answers

Basic Wastewater Operator Practice
Exam Questions With Correct Answers

What |is |the |predominant |organism |in |a |healthy |activated |sludge |treatment |plant?



A. |Stalked |ciliates

B. |rotifers

C. |nematodes

D. |amoebas |- |CORRECT |ANSWER✔✔-A. |Stalked |Ciliates



A |composite |sample |must |be?



A. |sporadically |collected |in |the |treatment |plant

B. |taken |at |one |time

C. |analyzed |immediately

D. |representative |and |sub-samples |time |spaced |over |15 |minutes |apart |- |CORRECT |
ANSWER✔✔-D. |representative |and |sub-samples |time |spaced |over |15 |minutes |apart



What |is |the |standard |volume |for |a |BOD |sample |bottle?



A. |150 |mL

B. |200 |mL

C. |300 |mL

D. |500 |mL |- |CORRECT |ANSWER✔✔-c. |300 |mL

,If |you |have |a |lime |slurry |feed |line, |what |is |the |best |valve |to |use?



A. |plug |valve

B. |butterfly |valve

C. |RPZ |dual |check |valve

D. |gate |valve |- |CORRECT |ANSWER✔✔-A. |plug |valve



5. |If |you |notice |a |predominance |of |rotifers |in |your |activated |sludge |sample |while |looking |at |it |
under |a |microscope, |what |does |this |indicate?



A. |healthy |sludge

B. |young |sludge

C. |old |sludge

D. |middle |age |sludge |- |CORRECT |ANSWER✔✔-C. |old |sludge



Calculate |the |BOD |using |the |given |information:

Initial |DO: |8.3

Final |DO: |5.9

Milliliters |of |sample |used: |2



a. |360 |mg/L

b. |210 |mg/L

c. |856 |mg/L

d. |36 |mg/L |- |CORRECT |ANSWER✔✔-a. |360 |mg/L

,If |your |activated |sludge |plant |begins |to |nitrify, |what |conditions |would |you |expect |to |decrease?



A. |settling |in |clarifiers

B. |chlorine |demand

C. |BOD |effluent

D. |TSS |in |effluent |- |CORRECT |ANSWER✔✔-a. |settling |in |the |clarifiers



How |do |you |calibrate |a |chemical |feed |pump?



A. |by |measuring |the |pump |output

B. |using |the |SWAG |method

C. |jar |test

D. |with |a |microscope |- |CORRECT |ANSWER✔✔-A. |by |measuring |the |pump |output



What |is |the |chemical |formula |for |sulfuric |acid?



a. |HNO3

b. |HCl

c. |NaOH

d. |H2SO4 |- |CORRECT |ANSWER✔✔-d. |H2SO4



What |is |the |most |common |type |of |activated |sludge |package |plants?



a. |extended |aeration

b. |sequential |batch |reactor

c. |oxidation |ditch

, d. |bardenpho |- |CORRECT |ANSWER✔✔-a. |extended |aeration



What |is |the |most |appropriate |method |of |reducing |the |F:M |ratio?



A. |increase |wasting

b. |decrease |wasting

c. |reduce |BOD |from |influent |flow

D. |add |polymer |to |RAS |to |increase |settling |- |CORRECT |ANSWER✔✔-b. |decrease |wasting



An |operator |notices |a |portion |of |the |aeration |tank |with |large |bubbles |rising |up. |What |is |the |
most |likely |problem?



a. |equal |air |distribution

b. |unequal |air |distribution |caused |by |a |blown/clogged |diffuser

c. |normal |operation

d. |reason |to |believe |the |air |filter |in |the |blower |is |clogged |- |CORRECT |ANSWER✔✔-b. |unequal |
air |distribution |caused |by |a |blown |diffuser



What |is |suction |lift?



a. |a |team |approach |to |lifting |heavy |objects

b. |the |pressure |on |the |suction |side |of |the |pump

c. |the |measurement |of |liquid |pressure |at |the |pump

d. |the |measure |of |how |bad |your |workers |lift |heavy |objects |- |CORRECT |ANSWER✔✔-b. |the |
pressure |on |the |suction |side |of |the |pump