Htaccess modify for PHP site and Wordpress work together

I need to modify .htaccess to work with custom php site and wordpress from the same root folder.
Now site works with dozen (30+) categories like:
site.com/about/
site.com/contact/
site.com/work/
and in .htaccess the record is:

RewriteRule ^([^.]*)/?$ /e/index.php?url1=$1&dom=%{HTTP_HOST} [QSA,NC,L]

It should to work with blog posts that will be in a root directory too and looks like
site.com/blog-post-1/
site.com/blog-post-2/
site.com/blog-post-3/
Wordpress files are located at site.com/blog/ directory.