Menu left

Hi there,
I have got another question. When I place a menu on the left position it will appear behind the text of the article. On the right site I have got no problems.
Here is the example

I want place menu's on both sides of the text. So please advise what I'm doing wrong.

Thanks again.

add this to bottom of template_css.css:

.column_left{
min-height:500px;
}