Wastewater Flashcards
The wastewater from the flushing of a water closet, latrine, or privy is referred to as
Black water
If a septic tank is pumped during a wet period, the
Tank may float out of the ground
Nutrients associated with eutrophication include all of the following except
Potassium
Which of the following is least important when reducing sewage to gases?
Earthworms
A septic tank maintenance worker has checked an empty tank for the presence of hydrogen sulfide. The test was negative, and there are no odors indicating the presence of other hazardous gases. Is the tank safe to enter without a respirator and supplied air?
No, because oxygen content and methane were not tested
All of the following are true about ozone as a disinfectant except
Long-lasting residual
Aerobic bacteria require all of the following nutrients except
Magnesium
What does a mottled brown and red soil indicate?
Inadequate aeration methods
Alternative small wastewater treatment systems are considered unless
Impervious formations are found at a depth of 10 feet
Lime coagulation, mixed media filtration, and activated carbon filtration will greatly reduce
EPA priority pollutants
It is known that some common pathogenic organisms found in wastewater will survive more than ? under harsh temperature extremes.
2 years
A storm sewer is used to
Remove rain and other standing surface water
Stream pollution is sometimes apparent by
A zone of degradation
A young lake is considered to be
Oligotrophic
Low in plant nutrients and containing abundant oxygen in the deeper parts
If the septic tank will also have a garbage disposal unit feeding into it, the
Size of the tank should be increased by 50%
Sludge accumulation in a tank serving normal home has been estimated at
18-21 gals. per person/year
How often should a septic tank for a private home be serviced?
Every 3-5 years
Human disease from aerosols of wastewater
Are related primarily to wastewater treatment by the activated sludge, trickling filter, and spray irrigation process
Plants absorb certain constituents of wastewater; using wastewater for irrigation of consumable plant products may present a health hazard to humans if the water contains
Cadmium
Found in drinking water supplies as a result of deterioration of galvanized plumbing, surface water contamination, etc.
After the servicing of a septic tank, it is essential that the tank and lid be
Replaced and secured for safety purposes
In addition to waterborne diseases, untreated wastewater discharges can also cause
Pollution from oxygen-demanding wastes, synthetic organic chemicals, inorganic chemicals, and mineral substances, pharmaceuticals, plant nutrients, sediments, and radioactive substances.
Wastewater management includes the control of
Centralized municipal and industrial sources of wastewater and decentralized subsurface wastewater treatment
What accounts for the largest volume of wastewater produced in the US?
Centralized municipal wastewater
What is a subsurface sewage treatment system commonly called?
Septic system
