Delete a site to permanently remove it from the
  repository. 
    When you delete a site you are deleting all of the site content. This includes library
      content, wiki pages, blog posts, calendar events, related links, discussion topics, and data
      lists. Only a site manager can delete a site.
    - 
        On the toolbar expand the Sites menu and
        click Search for Sites.
        
The Site Finder page displays.
 - 
        Search for a specific site or display all sites you have
        permission to access.
        
The results list appears beneath the search box. If you have permission to delete a site, the Delete action displays for that site.
 - 
        Click Delete for the site you want to
        delete.
        
A message prompts you to confirm the deletion.
 - 
        Click Delete to delete the selected
        site.
        
A message informs you that the selected action deletes all site content.
 - Click Yes.
 
The selected site is deleted in its entirety.