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The Ultimate Sewer and Septic Systems Quiz
by Staff
Most of us probably don't devote a lot of thought to what happens after we flush the toilet. However, occasionally problems do occur and understanding how the waste disposal system works can help us decide how to deal with them. Take this quiz and see what you can do to solve sewage problems.

What is wastewater?

  • water from a leaking faucet
  • sewage
  • water from the toilet cistern

Can sewage be simply dumped at sea?

  • if area is uninhabited within a 10-mile radius
  • 12 miles from the coast
  • definitely not

What effect can nitrogen and phosphates have on water in a stream?

  • cause excessively harmful growth of algae
  • renew oxygen in water
  • water dilutes and neutralizes them

What effect will increased bacteria have on stream water?

  • will supply food for the fish
  • will kill life forms
  • will help purify the water

Why would anyone want their own sewage system?

  • if it is too expensive to install a sewage system
  • to control their own waste
  • enjoy the benefits of free fertilizers

What is a septic tank?

  • a big hole in the yard
  • a plastic container placed near the drainage pipes of the home
  • large steel or concrete tank

How many layers are formed within a septic tank?

  • three layers
  • two layers
  • one layer

What causes gases to form in a septic tank?

  • nitrogen and phosphorous
  • bacteria breaking down organic matter
  • bad smell of waste in a sealed environment

If you have a P-trap, what is it?

  • something to separate liquid waste from solid
  • filter for the vent trap
  • loop of pipe preventing gasses from entering house

What is a drain field?

  • hole with perforated pipes
  • open field irrigated by filtered wastewater
  • container that catches rain

What is the typical size of a drain field?

  • 8 to 9 feet deep and 3 feet wide
  • 6 to 8 feet deep and 5 feet wide
  • 4 to 6 feet (about 1.5 m) deep and 2 feet (0.6 m) wide

How do you determine the size of a drain field?

  • budget
  • ability of ground to absorb water
  • size of backyard

Is a pump necessary for a septic system to work well?

  • of course
  • only if it is a large system
  • not if there is gravity

Is the saying "the grass is always greener over the septic tank" true?

  • not really
  • definitely
  • only when the septic tank is particularly active

How big is a sewer main?

  • at least 1 to 3 feet (0.3 to 1 m) wide
  • 3 to 5 feet (1 to 1.5 m) wide
  • 6 to 7 feet (1.8 to 2.1 m) wide

Where is a wastewater treatment plant usually located?

  • in a low area to utilize gravity
  • in any uninhabited area
  • on a hilltop to allow gasses to rise

Why are manhole covers round?

  • no particular reason
  • so the can easily be rolled away
  • so they can't fall down the hole

What usually happens when geography prevents gravity from moving wastewater?

  • A tunnel will be dug through the obstacle.
  • Wastewater will be pumped over the obstacle.
  • Wastewater is transported around obstacle in tankers.

How many stages are there in a sophisticated treatment plant?

  • one stage
  • two stages
  • three stages

Why should the effectiveness of a treatment plant be monitored?

  • because of possible environmental hazards
  • to ensure cost-effectiveness
  • to comply with local plumbing laws