
Presumably, you have an understanding of how the equation above has been derived, but as a brief review, recall what each of the terms signify:
| Q | The volumetric flow rate through the lake |
| V | The volume of the lake |
| k (t ) | The reaction rate coefficient of the contaminant |
| C (t ) | The concentration of the contaminant both within and exiting the lake |
| Cin(t ) | The concentration of the contaminant entering the lake |
Since we are interested in modeling inputs, we will look at Cin(t ) in more detail.