Good, this is easy!
So you can have a second WordPress installation in the directory blog2 (or whatever you want to call it).
Now the only problem is to figure out how users will navigate to each of the two blogs.
How do users navigate to the first blog? Do you redirect them from the home page? Do you have a link from a static home page? Or does everyone just link and bookmark www.mysite.org/blog/?
BTW, I want to mention that you have the option of creating a subdomain for your second blog. So you could have blog.mysite.org and blog2.mysite.org. Dunno if that appeals to you.
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