I'm not 100% sure what you are trying to do with this layout, are you trying to place the vertical navigation along the left side?
if that is the case, the problem is that you are not placing the vertical navigation in the Left column div.
You are creating a new div for the vertical navigation that is not a part of the main content div, that is placing a new div just under the main navigation div that has the same width as the main navigation div.
I dont believe you need to add a new div for the vertical navigation, you just need to place it within the the left column div that is already there.