4.2. Discussion of Boundary Conditions

Try these first

1. 1.

   What is a boundary condition in contaminant transport?

   Hint

   Think about the limits of a system.

2. 2.

   Define resuspension.

   Hint

   What happens to sediments in turbulent water?

3. 3.

   What is a semi-infinite system in contaminant transport?

   • A system with constant concentration far from the surface
   • A system that has infinite depth
   • A model assuming rapid fluctuation

   Hint

   Think about how far we expect constant conditions.

4. 4.

   True or False: In most contaminant transport scenarios, convection is typically slower than diffusion.

   • True
   • False

   Hint

   Consider the relative speeds of these processes.

5. 5.

   A contaminated sediment layer has an initial concentration of 150 mg/kg. If diffusion coefficient is known to diminish this by 20% over a set time, how will you expect flux to change?

   Hint

   Consider how diffusion directly corresponds to the concentration changes.

6. 6.

   In an experiment, sediment water interface measurements were taken before and after a storm, showing dramatic changes in contaminant levels. Discuss potential resuspension effects observed.

   Hint

   Think about how storm action affects sediment stability.