1.1. Constant Concentration Over Time

Try these first

1. 1.

   Define the steady state assumption.

   Hint

   What does it mean to be constant?

2. 2.

   What is a Gaussian dispersion model?

   Hint

   Think about how you would visualize concentrations of pollution.

3. 3.

   What does the steady state assumption imply about pollutant concentrations?

   • It remains constant over time.
   • It increases with time.
   • It decreases with time.

   Hint

   Think about the definition of steady state.

4. 4.

   Is the following statement true or false? 'The Gaussian dispersion model describes how pollutants can only spread in one direction.'

   • True
   • False

   Hint

   Consider how pollutants behave in the environment.

5. 5.

   A factory releases pollutants at a rate of 200 mg/s. How would you calculate the concentration in a 5 m³ volume at steady state?

   Hint

   What is the concentration formula using emission rates?

6. 6.

   If wind direction changes from East to West, how would this influence a nearby pollution plume's Gaussian distribution?

   Hint

   Consider how wind direction affects the behavior of any moving substance.