Why does my email address come up on Google?

I used to post on another website, a while ago. After no longer wanting to post there any more, I got one of the Mods to delete my posts for me. For some reason, even though a post with my email address is gone from the site, it still shows up in Google when I google for my email address.

Why does it do this and how can I get rid of it properly?

Google looked at the thread in the past, and still remembers looking at it then.

So will it disappear with time?

I can’t answer that.
You may be able to find the answer by checking google’s web site, but I suspect it MAY disappear with time… but perhaps not without a LOT of time. As in… years.

Yeah, maybe, perhaps …

If the page doesn’t exist any more and the only cache is googles then it should drop down the rankings as nothing will link to it. Of course if you google for your e-mail address and there aren’t many pages you’ll still find it. Eventually google will probably delete it’s cache of it, but I’m not sure what their policy is.

If you want it gone for good* then you can try to have google remove it. However you’ll probably have to request the webmaster of the site do that for you. This might be problematic depending if the board admin and the webmaster are the same person. The info can be found at this link.

*Of course this is the internet nothing is 100% gone forever, other people may have copied your post for whatever reason i.e. automated services like the wayback machine or a message board archiver, or real people who are keeping posts/threads/whole forums for whatever reason.