If you want to block Google from accessing certain pages you do this in a robots.txt file. This is not news to many webmasters, but what you may not realize is you need to specifically block Google instead of relying on a global bot block.
For example, this is what many use in their robots.txt to block bots from accessing the /block subdirectory (this is a hypothetical subdirectory)
This is what need to ALSO include in your robots.txt file to make sure Google is blocked:
Blocking Google can be useful to prevent unwanted pages from appearing in Google's public search index, and to prevent Google from knowing about certain links or pages.