WASTEWATER COLLECTIONS III FINAL EXAM ACTUAL
QUESTIONS AND SOLUTIONS RATED A+
✔✔WHAT IS A PNEUMATIC EJECTOR?
A. A TYOR OF LIFTSTATION PUMP DEVICE - ✔✔A. A TYOE OF LIFTSTATION
PUMP DEVICE.
USED IN SMALL LIFTSTATIONS
✔✔IF A CENTRIFUGAL PUMP INCREASES ITS SPEED BY 25% THERE IS A
__________ INCREASE IN MOTOR SPEED
A. 25%
B. 56%
C. 95% - ✔✔C. 95%
A 25% OVERSPEED RESULTS IN 25% MORE CAPACITY, 56% MORE HEAD AND
REQUIRES 95% MORE MOTOR HORSEPOWER.
✔✔WHAT ARE THE CHARACTERISTICS OF FRESH SEWAGE? - ✔✔DISHWATER
GREY, SLIGHT FECAL ODOR, HAS FLOATING PARTICLES
✔✔SEPTIC SKUDGE?
A. SMELLS GOOD
B. HAS A SWEET SMELL
C. MORE DIFFICULT TO TREAT - ✔✔C. MORE DIFFICULT TO TREAT
SPETIC SLUDGE CAUSES OPERATING PROBLEMS
✔✔AS TRAFFIC SPEEDS GO UP AROUND CONSTRUCTION SITE, WHAT
HAPPENS TO THE SPACING BETWEEN THE WARNING DEVICES? - ✔✔INCREASE
THIS IS A BEST GUESS
✔✔FREQUENT STARTS AND STOPS OF A MOTOR CAUSES?
A. CAUSES EXCESSIVE WEAR ON CONTROL CIRCUIT RELAYS
B. CAUSES EXCESSIVE WEAR ON MOTORS
C. CAUSES CAVITATION
D. CONSUMES LESS ENERGY THAN A MOTOR THAT OPERATES
CONTINUOUSLY
E. KEEPS SOLIDS SUSPENDED IN A WET WELL - ✔✔
, ✔✔THE PRIMARY CAUSE OD SEWER STOPPAGE IS? - ✔✔ROOTS AND GREASE
✔✔WHEN USING A HIGH VELOCITY JET MACHINE?
A. ENTER ON THE UPSTREAM SIDE
B. ENTER ON THE DOWNSTREAM SIDE
C. ETC. - ✔✔B. ENTER FROM THE DOWNSTREAM SIDE
DIRECT HOSE AND NOZZLE UPSTREAM
✔✔HOW FAR MUST EQUIPMENT BOOMS STAY FROM POWER LINES?
A. 5ft.
B. 10ft.
C. 20ft.
D. 25ft. - ✔✔B. 10ft.
✔✔IF THE LEVEL OF THE FLOAT SWITCH THAT TURNS ON THE LEAD PUMP IS
LOCATED ABOVE THE LEVEL OF THE GRAVITY FED INFLUENT LINE WHAT
HAPPENS?
A. GREASE BUILDS UP ON THE INFLUENT LINE
B. THE INFLUENT LINE REMAINS PARTIALLY FULL ALL OF THE TIME
C. THE INFLUENT LINE REMAINS FULL ALL OF THE TIME. - ✔✔C. THE INFLUENT
LINE REMAINS FULL ALL OF THE TIME.
✔✔WHAT ARE THE CRITERIA FOR SELECTING CORRECT TYPE OF PIPE? - ✔✔1.
CHEMICAL CHARACTERISTICS OF WATER IN THE PIPE
2. CHARACTERISTICS OF INDUSTRIAL WASTE
3. POSSIBILITY OF SEPTIC CONDITIONS
4. EXCLUSION OF INFILTRATION
5. EXTERNAL FORCES
6. INTERNAL FORCES
7. ABRASION
✔✔WHAT IS THE MINIMUM VELOCITY ACCEPTABLE IN THE COLLECTION
SYSTEM? - ✔✔2FT PER SECOND
(DESIRABLE FLOW IS 3 -5FT PER SECOND)
✔✔A DROP MANHOLE IS USED WHEN?
A. ONE OF THE CHOICES HAD SOMETHING TO DO WITH A 24 INCH DROP
B. THE LINE VELOCITY IS GREATER THAN 10FT PER SEC. AND THE DROP
MANHOLE IS USED TO SLOW IT DOWN.
QUESTIONS AND SOLUTIONS RATED A+
✔✔WHAT IS A PNEUMATIC EJECTOR?
A. A TYOR OF LIFTSTATION PUMP DEVICE - ✔✔A. A TYOE OF LIFTSTATION
PUMP DEVICE.
USED IN SMALL LIFTSTATIONS
✔✔IF A CENTRIFUGAL PUMP INCREASES ITS SPEED BY 25% THERE IS A
__________ INCREASE IN MOTOR SPEED
A. 25%
B. 56%
C. 95% - ✔✔C. 95%
A 25% OVERSPEED RESULTS IN 25% MORE CAPACITY, 56% MORE HEAD AND
REQUIRES 95% MORE MOTOR HORSEPOWER.
✔✔WHAT ARE THE CHARACTERISTICS OF FRESH SEWAGE? - ✔✔DISHWATER
GREY, SLIGHT FECAL ODOR, HAS FLOATING PARTICLES
✔✔SEPTIC SKUDGE?
A. SMELLS GOOD
B. HAS A SWEET SMELL
C. MORE DIFFICULT TO TREAT - ✔✔C. MORE DIFFICULT TO TREAT
SPETIC SLUDGE CAUSES OPERATING PROBLEMS
✔✔AS TRAFFIC SPEEDS GO UP AROUND CONSTRUCTION SITE, WHAT
HAPPENS TO THE SPACING BETWEEN THE WARNING DEVICES? - ✔✔INCREASE
THIS IS A BEST GUESS
✔✔FREQUENT STARTS AND STOPS OF A MOTOR CAUSES?
A. CAUSES EXCESSIVE WEAR ON CONTROL CIRCUIT RELAYS
B. CAUSES EXCESSIVE WEAR ON MOTORS
C. CAUSES CAVITATION
D. CONSUMES LESS ENERGY THAN A MOTOR THAT OPERATES
CONTINUOUSLY
E. KEEPS SOLIDS SUSPENDED IN A WET WELL - ✔✔
, ✔✔THE PRIMARY CAUSE OD SEWER STOPPAGE IS? - ✔✔ROOTS AND GREASE
✔✔WHEN USING A HIGH VELOCITY JET MACHINE?
A. ENTER ON THE UPSTREAM SIDE
B. ENTER ON THE DOWNSTREAM SIDE
C. ETC. - ✔✔B. ENTER FROM THE DOWNSTREAM SIDE
DIRECT HOSE AND NOZZLE UPSTREAM
✔✔HOW FAR MUST EQUIPMENT BOOMS STAY FROM POWER LINES?
A. 5ft.
B. 10ft.
C. 20ft.
D. 25ft. - ✔✔B. 10ft.
✔✔IF THE LEVEL OF THE FLOAT SWITCH THAT TURNS ON THE LEAD PUMP IS
LOCATED ABOVE THE LEVEL OF THE GRAVITY FED INFLUENT LINE WHAT
HAPPENS?
A. GREASE BUILDS UP ON THE INFLUENT LINE
B. THE INFLUENT LINE REMAINS PARTIALLY FULL ALL OF THE TIME
C. THE INFLUENT LINE REMAINS FULL ALL OF THE TIME. - ✔✔C. THE INFLUENT
LINE REMAINS FULL ALL OF THE TIME.
✔✔WHAT ARE THE CRITERIA FOR SELECTING CORRECT TYPE OF PIPE? - ✔✔1.
CHEMICAL CHARACTERISTICS OF WATER IN THE PIPE
2. CHARACTERISTICS OF INDUSTRIAL WASTE
3. POSSIBILITY OF SEPTIC CONDITIONS
4. EXCLUSION OF INFILTRATION
5. EXTERNAL FORCES
6. INTERNAL FORCES
7. ABRASION
✔✔WHAT IS THE MINIMUM VELOCITY ACCEPTABLE IN THE COLLECTION
SYSTEM? - ✔✔2FT PER SECOND
(DESIRABLE FLOW IS 3 -5FT PER SECOND)
✔✔A DROP MANHOLE IS USED WHEN?
A. ONE OF THE CHOICES HAD SOMETHING TO DO WITH A 24 INCH DROP
B. THE LINE VELOCITY IS GREATER THAN 10FT PER SEC. AND THE DROP
MANHOLE IS USED TO SLOW IT DOWN.
