SEO – Allowed or Not?

So I recently implemented WordPress into a clients site. They informed me today – after going live two weeks ago – that they apparently had two home pages – one optimized for Portland, Oregon and another optimized for Beaverton, Oregon.

Now, the secondary index page they used (Beaverton) was hidden and could only be accessed via the search engine result or a direct link to the page (which only the client could have informed me existed and provided to me). So now they no longer rank in the top five on Google (actually they’re not even on the page anymore) because this page has been deleted.

I can go ahead and recreate this page, but my question is: Isn’t it against Google’s policies to have duplicate pages with slightly modified content like this?

If so, any recommendations on the best way to go about targeting two geographic locations on Google to replace this former practice? Thank you!